description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
|---|---|---|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to hermetic compressors, more particularly, to an apparatus for separating lubricating oil from a mixture of gaseous refrigerant and oil in hermetic compressors.
2. Description of the Related Art
In general, hermetic compressors include a hermetic body which encloses a motor unit and a compressing unit. The hermetic compressor compresses a gaseous refrigerant input from an evaporator. At this time, the gaseous refrigerant changes its state from high temperature and low pressure into high temperature and high pressure. The compressed refrigerant, i.e., the refrigerant having a high temperature and a high pressure is discharged out of the compressor.
As shown in FIGS. 1 through 3, such a hermetic compressor includes a hermetic body 100 in which a motor unit 110 and a compressing unit 120 are installed at respective upper and lower portions thereof. The motor unit 110 enables the compressing unit 120 to suck-in a refrigerant, to compress the sucked-in refrigerant, and to discharge the compressed refrigerant.
The motor unit 110 includes a stator 111 and a rotor 112 which rotates depending on an electromagnetic relation with the stator 111. A crankshaft 113 is press-fitted in a through hole of the rotor 112.
The compressing unit 120 includes a cylinder 123 that provides a chamber for compressing the refrigerant input through a suction tube 121. A piston 124 is reciprocated in the cylinder 123 by the rotation of the crankshaft 113. A cylinder head 125 closes an end of the cylinder 123. Between the cylinder 123 and the cylinder head 125, a valve unit including a suction reed valve (not shown), a valve plate 126 and a discharge reed valve 127 is inserted. The suction reed valve, the valve plate 126 and the discharge reed valve 127 are used for respectively admitting refrigerant into the cylinder 123 and discharging the refrigerant out of the cylinder 123 after the refrigerant is compressed.
When power is supplied to the motor unit 110, the crankshaft 113 is rotated thereby to reciprocate the piston 124 in the cylinder 123. As a result, steps of sucking, compressing and discharging the refrigerant are carried out.
As shown in FIGS. 1 and 3, a refrigerant travels through the suction tube 121, a suction muffler 122, a suction chamber 125a of the cylinder head 125, and a suction hole 126a of the valve plate 126, successively. The refrigerant is then compressed by the piston 124.
Thereafter, the compressed refrigerant is passed through a discharge hole 126b and pushes open the discharge reed valve 127. The refrigerant is then discharged out of the body 100 through a discharge chamber 125b of the cylinder head 125, and a discharge tube 128, successively.
Generally, in a refrigeration cycle using such a compressor, a lubrication oil is mixed with the liquid refrigerant in order to lubricate mechanically removable parts. During the cycle, the mixture is passed through the evaporator wherein the liquid refrigerant, having a low temperature and a low pressure, is changed into a gaseous refrigerant. Thereafter the gaseous refrigerant is fed into the compressor. However, the lubrication oil contained in the refrigerant is still in its liquid state and is fed into the cylinder 123 of the compressor.
In other words, as shown in FIG. 3, the lubrication oil fed through the suction tube 121 together with the refrigerant is sucked along the internal side of a connecting spring 129 into the suction muffler 122. The sucked refrigeration oil is fed into the cylinder 123 through the valve 126 and is discharged through the valve 127.
However, the oil fed into the cylinder 123 of the compressor may reduce the efficiency of suction, compression and discharge of the gaseous refrigerant. This may result in a reduced refrigeration capacity of machineries using the compressors.
In addition, oversupply of the oil through the valves 126 and 127 may cause a valve unit failure.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an apparatus for separating lubricating oil from a refrigerant when the refrigerant and the oil contained in the refrigerant are conducted toward a cylinder of a hermetic compressor.
The invention pertains to a hermetic compressor comprising a cylinder forming a compressing chamber having gas inlet and outlet openings; a piston reciprocally mounted in the cylinder for compressing gas in the chamber; a motor for reciprocating the pistons; and a conducting structure connected to the inlet opening for conducting a mixture of gaseous refrigerant and liquid oil, and for separating the oil from the refrigerant. The conducting structure includes a suction muffler having an inlet port, and a conduit arrangement connected to the inlet port. The conduit arrangement includes an outer tube for conducting the mixture with at least most of the liquid oil travelling radially outside of the gaseous refrigerant. An inner tube is disposed at an end of the outer tube and communicates with the inlet port for conducting thereto gaseous refrigerant received from the outer tube. The inner tube is spaced radially inwardly of the outer tube for forming a channel therebetween. The channel includes an open upstream end for receiving liquid oil from the outer tube, whereby the inner tube separates gaseous refrigerant from liquid oil. The channel includes an oil discharge opening disposed downstream of the upstream end of the channel for discharging liquid oil from the channel.
BRIEF DESCRIPTION OF THE DRAWINGS
The above object and other advantages of the present invention will become more apparent by describing in detail the preferred embodiment thereof with reference to the attached drawings, in which:
FIG. 1 is a cross-sectional view of a conventional hermetic compressor;
FIG. 2 is a cross-sectional view of the conventional hermetic compressor of FIG. 1 when rotated by 90°.
FIG. 3 illustrates flow of a refrigerant and oil through a suction tube and a suction muffler into a conventional hermetic compressor;
FIG. 4 illustrates flow of a refrigerant and oil through a suction tube and a suction muffler into a hermetic compressor according to a first embodiment of the present invention;
FIG. 5 is an enlarged cross-sectional view of a portion A of FIG. 4;
FIG. 6 is an exploded view of FIG. 5; and
FIG. 7 illustrates flow of a refrigerant and oil through a suction tube and a suction muffler into a hermetic compressor according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the elements are exaggerated for clarity.
As a conventional hermetic compressor described referring to FIGS. 1 and 2, the hermetic compressor according to the present invention includes a hermetic body 100 which encloses a motor unit 110 and a compressing unit 120 which are respectively arranged on an upper and a lower portion thereof. The compressor is connected within a refrigeration cycle in which there is circulated a mixture of refrigerant and lubrication oil. The motor unit 110 enables the compressing unit 120 to suck-in, compress and discharge the refrigerant. The motor unit 110 includes a stator 111 and a rotor 112. The rotor 112 rotates depending on an electric relation with the stator 111. A crankshaft 113 is press-fitted in a through hole of the rotor 112. The compressing unit 120 includes a cylinder 123 providing a compression chamber for compressing the refrigerant input through a suction tube 121 which constitutes a portion of a conduit structure conducting a refrigerant. A piston 124 is reciprocated in the cylinder 123 by the rotation of the crankshaft 113. A cylinder head 125 closes an end of the cylinder 123. Between the cylinder 123 and the cylinder head 125, a valve unit including a suction reed valve (not shown) covering an inlet opening of the compression chamber, a valve plate 126 and a discharge reed valve 127 is inserted. The valve plate 126 and the discharge reed valve 127 are respectively used for admitting refrigerant into the cylinder 123 and discharging compressed refrigerant out of the cylinder 123.
An apparatus for separating lubrication oil from the refrigerant according to the present invention includes an oil separating tube 130 disposed between the suction tube 121 and an inlet port P of the suction muffler 122. The tube 130 forms part of the conduit structure.
The separating tube 130 has a smaller diameter than the suction tube 121 such that mainly only the gaseous refrigerant 140 flows through a flow passage formed by the separating tube 130, and the lubrication oil 150 flows into an upstream end of a channel C formed between an inner surface of the tube 121 (which defines an outer channel wall) and the outer surface of the tube 130 (which defines an inner channel wall).
A rubber packing 131 is mounted on the outer circumference of the separating tube 130 and prevents the oil 150 flowing along the outer circumference of the separating tube 130 from entering the suction muffler 122.
Furthermore, oil discharge holes 121a are formed in the upper portion of the suction tube 121 downstream of the upstream end of the channel C. The oil 150 whose travel is blocked by the rubber packing 131 is discharged through the oil discharge holes 121a of the suction tube 121.
The suction muffler 122 includes an oil cut-off wall 122a (see FIG. 4) which surrounds and rises above an entrance 122b of a vertically oriented refrigerant-conducting passage 122c. That wall 122a prevents any oil 150 that may have passed through the separating tube 130, from reaching a suction hole 126a of the valve plate 126.
The operation of the apparatus for separating lubrication oil from a refrigerant of the hermetic compressor according to the first preferred embodiment of the present invention will be described hereinafter.
When the motor unit 110 is supplied with power, the crankshaft 113 is rotated. The crankshaft 113 reciprocates the piston 124 in the cylinder 123. As a result, steps of sucking, compressing and discharging of the refrigerant are carried out.
A refrigerant 140 that is heat-exchanged in an evaporator through a refrigeration cycle, is sucked through the suction tube 121 of the compressor. At this time, the refrigerant 140 is in its gaseous state having a high temperature and a low pressure.
Since lubrication oil 150 that is contained in the refrigerant 140 and sucked through the suction tube 121 together with the refrigerant 140 is in a liquid state, it flows along the inner circumference of the suction tube 121 and is discharged through the oil discharge holes 121a formed on the upper edge portion of the suction tube 121.
Refrigerant 140' from which the oil 150 has been removed in the above mentioned manner, is passed through the separating tube 130 and fed into the suction muffler 122.
Oil that travels along the outer surface of the separating tube 130 is blocked by the rubber packing 131 from entering the suction muffler 122. That oil then travels along the rubber packing 131 and is discharged through the oil discharge holes 121a.
As aforementioned, the present invention provides that mainly only the refrigerant 140' from which the oil has been separated, enters the suction muffler 122. The refrigerant 140' entering the suction muffler 122 is passed through the suction hole 126a of the valve plate 126. Any oil 150 that may have passed through the separating tube 130 is prevented from entering the cylinder 123 through the suction hole 126a of the valve plate 126 by the oil cut-off wall 122a of the suction muffler 122.
The refrigerant 140' passed through the suction hole 126a of the valve plate 126 is delivered into the cylinder 123 and compressed by the piston 124. The compressed refrigerant 140' having a high temperature and a high pressure is discharged out of the compressor past the discharge reed valve 127 and discharge tube 128. Thereafter, the refrigerant 140' is introduced into a condenser.
FIG. 7 shows an apparatus for separating from a refrigerant according to another embodiment of the present invention. As shown in FIG. 7, a refrigerant passage tube 231 having a smaller diameter than the suction tube 121 is formed integrally of one piece with the suction tube 121, so that pure refrigerant 140' can be passed through the refrigerant passage tube 231 into the suction muffler 122. The oil 150 flowing along the inner circumference of the suction tube 121 can be discharged out of the suction tube 121 through discharge holes 232 formed on the upper edge portion of the suction tube 121.
The operation of the oil separating apparatus according to the second embodiment of the present invention is as follows. First, a refrigerant/oil mixture 140 is sucked through the suction tube 121. Pure refrigerant 140' of the sucked mixture 140 is conducted into the suction muffler 122 through the refrigerant passage tube 231. The oil 150 flowing along the inner circumference of the suction tube 121 is discharged out of the suction tube 121 through the oil discharging holes 232. Thus, the oil 150 is separated from the mixture 140.
As aforementioned, the present invention is capable of separating, from the refrigerant, oil that may cause a degradation of the efficiency of the hermetic compressor.
Accordingly, the efficiency of the hermetic compressor and the evaporative latent heat of the evaporator are enhanced. This results in an improved freezing performance.
This invention has been described above with reference to the aforementioned embodiments. It is evident, however, 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 scope of the appended claims. | A hermetically sealed compressor includes a cylinder forming a compression chamber, and a piston reciprocally mounted in the cylinder for compressing gaseous refrigerant. A mixture of gaseous refrigerant and lubricating oil is conducted via a conduit arrangement to a suction muffler located upstream of the compression chamber. The conduit arrangement includes, at an inlet to the suction muffler, radially inner and outer tubes forming a channel therebetween. Gaseous refrigerant flows into the suction muffler through the inner tube. Lubricating oil traveling radially outwardly of the gaseous refrigerant enters the channel and is discharged from a downstream end of channel and thus does not enter the suction muffler. | 8 |
[0001] This application claims the benefit of Taiwan application Serial No. 103114507, filed Apr. 22, 2014, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates in general to a computing device and a method of controlling a computing device to process secure services, and more particularly, to a computing device in which a core of a processing unit is capable of processing multiple secure services based on one-time mode conversion, and a method of controlling a computing device to process secure services.
[0004] 2. Description of the Related Art
[0005] To increase the security level of systems, cores of many current processing units support operations in a trusted execution environment (TEE, to be referred to as a secure mode). An environment in contrast with the TEE is referred to as an open execution environment (also known as a rich execution environment, REE, to be referred to as a general mode). In the general mode, the core of the processing unit executes a normal operation system (normal OS) to process mostly user-related operations, e.g., Internet browsing, multimedia playing and application downloading. In the secure mode, the core of the processing unit executes a secure operation system (secure OS) to process system and data security-related operations, e.g., secure services such as digital right management (DRM) and online payments. When a secure service arises, the core of the processing unit switches from the general mode to the secure mode to process the secure service. In practice, the core enters the secure mode from the general mode according to a predetermined secure mode calling instruction. For example, the instruction may be a secure monitor call (SMC) instruction designed by ARM, or a safer mode extension (SMX) instruction designed by Intel. One secure service usually has one corresponding service identification (service ID). For example, when the SMC instruction notifies the core to process a secure service, the service ID corresponding to the secure service is also issued. The core processes the secure service according to the service ID after having entered the secure mode, and returns to the general mode after having processed the secure service.
[0006] FIG. 1 shows a schematic diagram of a core of a conventional processing unit during conversion between a general mode and a secure mode. When a core 130 , in a general mode 110 , learns that a first secure service (service ID: 001) is generated at a time point T1, the core 130 issues an SMC instruction (e.g., SMC: 001) carrying a service ID 001 to enter a secure mode 120 to process the first secure service, and returns to the general mode 110 after having processed the first secure service. At a time point T2, when the core 130 learns that a second secure service (service ID: 002) is generated, the core 130 issues an SMC instruction (e.g., SMC: 002) carrying a service ID 002 to enter the secure mode 120 to process the second secure service, and returns to the general mode 110 after having processed the second secure service. In the above design, the core 130 is limited by one restriction—the core 130 having entered the secure mode can only process one secure service. More specifically, even when the second secure service is generated while the first secure service is being processed, the core 130 needs to wait till the first secure service is completely executed, return to the general mode 110 and then issue the second SMC instruction in order to process the second secure service. The above limitation poses a great restriction on the core when the core executes the secure OS to undesirable affect the processing unit and even overall performance of a computing device using the processing unit.
SUMMARY OF THE INVENTION
[0007] In view of the drawbacks of the prior art, it is an object of the present invention to provide a computing device and a method of controlling a computing device to process secure services, so as to allow a core of the processing unit with better performance in a secure mode.
[0008] The present invention discloses a method of processing secure services applied to a processing unit of a computing device to control the processing unit to process multiple secure services. The computing device includes a storage unit. The method includes: controlling a core of the processing unit to perform following steps in a secure mode: accessing the storage unit to obtain a first command that includes first secure service information, processing a first secure service associated with the first secure service information according to the first command, and accessing the storage unit to obtain a second command that includes second secure service information. During a period from a time point that the core accesses the storage unit to obtain the first to a time point that the core accesses the storage unit to obtain the second command, the core is controlled to stay in the secure mode.
[0009] The present invention further discloses a computing device. The computing device comprises: a processing unit, comprising a core, the core in a general mode entering a secure mode according to a secure mode calling instruction; and a storage unit, coupled to the processing unit, storing a first command that includes first secure service information. In the secure mode, the core accesses the storage unit to obtain the first command, processes a first secure service associated with the first secure service information according to the first command, and accesses the storage unit to obtain a second command that includes second secure service information. During a period from a time point that the core accesses the storage unit to obtain the first to a time point that the core accesses the storage unit to obtain the second command, the core is controlled to stay in the secure mode
[0010] The computing device and the method of controlling a computing device to process secure services allow a core of a processing unit to stay in the secure mode, and to only return to the general mode after having processed multiple secure services. Compared to the prior art, instead of being restricted by a secure OS for a long period of time, the core of the present invention is capable of flexibly processing multiple secure services in the secure mode. Further, with the present invention, a time slice mechanism may be designed in a secure OS to provide the secure OS with a multi-thread function to enhance the performance of the core in the secure mode.
[0011] The above and other aspects of the invention will become better understood with regard to the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic diagram of a core of a conventional processing unit during conversion between a general mode and a secure mode in order to process a secure service;
[0013] FIG. 2 is a schematic diagram of a core of a computing device during conversion between a general mode and a secure mode in order to process secure services according to an embodiment of the present invention;
[0014] FIG. 3 is a schematic diagram of a method of controlling a computing device to process secure services according to an embodiment of the present invention;
[0015] FIG. 4 is a schematic diagram of a core of a computing device during conversion between a general mode and a secure mode in order to process secure services according to another embodiment of the present invention; and
[0016] FIG. 5 is a schematic diagram of a method of controlling a computing device to process secure services according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Technical terms of the application are based on the general definition in the technical field of the application. If the application describes or explains one or some terms, definitions of the terms are based on the description or explanation of the application.
[0018] The present invention discloses a computing device and a method of controlling a computing device to process secure services, so as to allow a core in a secure mode to process multiple secure services. The device and method are applicable to a processing unit having a secure mode and a general mode. In possible implementation, one skilled person in the art may choose equivalent devices or steps to implement the disclosure based on the disclosure of the application. That is, the implementation of the disclosure is not limited in the embodiments described in the disclosure. Further, a part of the elements included in the computing device of the disclosure may be individually known. Without affecting the full disclosure and possible implementation of the computing device, the known details are omitted. Further, the method of controlling a computing device to process secure services of the present invention may be implemented by the computing device of the disclosure or an equivalent device. Without affecting full disclosure and possible implementation of the method, details of the method focus on steps instead of hardware.
[0019] FIG. 2 shows a schematic diagram of a core of a computing device during a conversion between a general mode and a secure mode to process secure services according to an embodiment of the present invention. The computing device of the present invention may be a consumer electronic product, e.g., a computing device having data process and computation capabilities, such as a television, a cell phone or a multimedia player. These devices usually include a processing unit and a storage unit. The processing unit at least includes a core 210 . The core 210 is operable in a general mode 110 and a secure mode 120 , and is adapted to access a storage unit 220 in the general mode 110 and in the secure mode 120 . For example, the storage unit 220 may be a certain section of a system memory of the computing device, or a certain hardware register. FIG. 3 shows a schematic diagram of a method of controlling a computing device to process secure services according to an embodiment of the present invention. After the storage unit 220 is provided (step S 310 ), when a secure service is generated, the secure service triggers the core 210 capable of processing the secure service to converse the mode (step S 320 ). Before the core 210 enters the secure mode 120 (indicated by dotted lines in FIG. 2 ), a command (Cmd) associated with the secure service, e.g., a command including a service ID, is stored into the storage unit 220 (step S 330 ), and a secure mode calling instruction (e.g., an SMC instruction designed by ARM) is generated. According to the instruction, the core 210 enters the secure mode 120 (step S 340 ). It should be noted that, compared to the prior art, as the service ID is previously stored into the storage unit 220 in step S 330 , the secure mode calling function need not carry the service ID of the secure service. After having entered the secure mode, the core 210 reads the command 225 from the storage unit 220 , and processes the secure service according to the service ID included in the command 225 (step S 350 ). In general, the secure service has a priority level higher than those of other services. Thus, after the core 210 completes processing the current secure service, if the storage unit 220 further includes other command 225 , the core 210 completes processing all the secure services associated with the other commands 225 in the storage unit 220 , and then returns to the general mode 110 . That is to say, as the core 210 enters the secure mode and processes the secure service, before returning to the general mode 110 , the core 210 first checks whether there are other commands in the storage unit 220 . For example, the core 210 checks the storage unit 220 by a polling method at a predetermined interval, and only returns to the general mode 110 when it is ascertained that there are no other secure services to be processed. The other commands may be other commands associated with secure services, and may be stored into the storage unit 220 before the core 210 processes the current secure service or may be stored into the storage unit 220 as the core 210 begins processing the current secure service.
[0020] FIG. 4 shows a schematic diagram of a core of a computing device during conversion between a general mode and a secure mode in order to process a secure service according to another embodiment of the present invention. As functions of the processing unit expand, the number of cores provided also increases. When the processing unit includes two or more cores, at least one of the cores is designed as a secure core. Only the secure core is able to enter a secure mode to process secure services, whereas the remaining cores stay in a general mode to process other services. In the embodiment in FIG. 4 , the processing unit of the computing device includes two cores—a core 410 and a core 420 . The core 410 is a secure core, and is adapted to enter a secure mode when triggered by a secure mode calling instruction. The core 420 is a non-secure core, or referred to as a general core. In other embodiments, the processing unit of the computing device may include more cores, e.g., four cores, and the number of secure cores is not limited to one, e.g., two of the four cores are designed as secure cores. FIG. 5 shows a schematic diagram of a method of controlling a computing device to process secure services according to another embodiment of the present invention. Same as that in the previous embodiment, a storage unit 220 for storing a command including a secure ID is first provided (step S 510 ). When a secure service is generated, the secure service triggers the core 410 to converse the mode (step S 520 ). However, this secure service may be received by the secure core 410 or the non-secure core 420 . Whether the secure core 410 or the non-secure core 420 receives the secure service event, the command 225 associated with the secure service, e.g., the command including the service ID, is stored into the storage unit 220 (step S 530 ). It is then determined whether the core that receives the secure service event is the secure core (step S 540 ). If the core 420 receives the secure service event, as the core 420 is not the secure core, a notification (Notify) is issued to inform the core 410 to process the secure service (step S 550 ). The core 410 generates an exception process (exception) due to the notification (Notify) (step S 560 ). This exception process causes the core 410 to enter the secure mode 120 . However, if the above secure service event is received by the core 410 , a determination result of step S 540 is affirmative such that step S 570 is directly performed. In step S 570 , the core 410 determines whether it is in the secure mode 120 .
[0021] If the core 410 is not in the secure mode 120 , the core 410 generates a secure mode calling instruction (step S 580 ), according to which the core 410 enters the secure mode 120 to process the secure service (step S 590 ). That is, the core 410 reads the command 225 from the storage unit 220 , and processes the associated secure service according to the command 225 . When a determination result of step S 570 is affirmative, i.e., when the core 410 is already in the secure mode 120 while the exception process is generated (indicating that the core 410 is currently processing another secure service), without exiting the secure mode 120 and again entering the secure mode 120 , the core 410 may immediately process the secure service after having processed the current secure service (step S 590 ).
[0022] For example, the above storage unit may be a certain section of the system memory of the computing device or a certain hardware register, and the core may access either of the two in both the general mode 110 and the secure mode 120 . The notification (Notify) in step S 550 may be a software generated interrupt (SGI) or a hardware generated interrupt. For example, the hardware interrupt is a mailbox interrupt mechanism, under which the core 420 in the general mode 110 writes the command 225 to the hardware register and sends the interrupt to inform the core 410 of a new command generated in the hardware register.
[0023] It should be noted that, when the core 410 in the secure mode 120 processes the secure service, if a new secure service is generated at this point, the core 420 will receive this secure service event. Accordingly, the core 420 stores a command associated with the secure service into the storage unit 220 (step S 530 ), and issues the notification (Notify) to inform the core 410 (step S 550 and step S 560 ). According to the notification (Notify) from the core 420 , the core 410 learns that a new command 225 is generated in the storage unit 220 . Thus, rather than immediately returning to the general mode 110 after having processed the current secure service, the core 410 accesses the storage unit 220 to obtain the new command 225 according to the above notification, and processes the new secure service associated with the new command. In other words, in the architecture of the embodiment, unlike the prior art in which a next secure service cannot be issued because the secure core 410 in the secure mode 120 is currently processing a secure service, in the present invention, the core 410 is capable of processing an interrupt issued by the core 420 after the core 410 enters the secure mode. Therefore, the core 410 in the secure mode 120 is still capable of receiving notifications (Notify) corresponding to different secure services, and consecutively processing more than one secure service. For example, when core 420 continuously stores commands 225 into the storage unit 220 while the core 410 is in the secure mode 120 , the core 410 is capable of continuously processing newly happened secure services. That is, in one period during which the core 410 enters the secure mode 120 , the core 410 is capable of processing more than one secure service, so as to provide greater flexibilities when the core 410 executes a secure OS.
[0024] Further, through a time slice mechanism, the present invention allows a secure OS to support multi-thread scheduling. When the design of multi-thread scheduling is available, the core 410 may first return to the general mode 110 as the time slice ends even if the secure service is not yet completely processed. For example, when the core 410 processes a secure service, data needs to be moved through a direct memory access (DMA) unit. When the DMA unit starts operating after the command is issued, if the task of the DMA unit is not yet complete as the time slice ends and there are no other commands to be processed in the storage unit 220 , the core 410 at this point first returns to the general mode 110 to support processing other services in order to prevent wasting time in the secure mode 120 . After the DMA unit completes the task, the core (the core 410 or the core 420 ) in the general mode 110 is informed. Steps 570 to S 590 are preformed if the core 410 receives the notification, or else steps S 550 to S 590 are performed if the core 420 receives the notification. That is to say, without wasting computing resources on waiting, the core 410 may flexibly convert between the general mode 110 and the secure mode 120 during the course of processing the secure service, thereby providing operations of the entire processing unit with better efficiency. In a preferred embodiment, if the secure OS is given a time slice design, as the time slice ends, the core 410 first verifies whether a command to be processed is stored in the storage unit 220 . If so, the core 410 stays in the secure mode 120 to process the secure service; if the storage unit 220 is empty, the core 410 returns to the general mode 110 .
[0025] In another embodiment, the secure core 410 does not enter the secure mode 120 from the general mode 110 according to the notification from the core 420 . Alternatively, a predetermined period (e.g., a time slice) is set, and the core 410 initiatively issues a secure mode calling instruction when the predetermined period is reached to prompt itself to enter the secure mode 120 . Thus, the core 410 may periodically enter the secure mode 120 to check whether there is a newly generated secure service. In a preferred embodiment, the above method may be implemented in parallel with the notification. That is to say, in addition to periodically entering the secure mode 120 to check whether there is a newly generated secure service, the core 410 may also enter the secure mode 120 to check whether there is a newly generated secure service through the notification from the other core 420 .
[0026] One person skilled in the art can understand implementation details and variations of the method in FIG. 3 and FIG. 5 from the disclosure of the device in FIG. 2 and FIG. 4 . Without affecting full disclosure and implementation of the method of the present invention, repetitive details are omitted herein. It should be noted that, the shapes, sizes, ratios and sequences of the steps in the drawings are examples for explaining the present invention to one person skilled in the art, not limiting the present invention. In possible implementation, one skilled person in the art would selectively implement part or all technical features of any embodiment of the application or selectively combine part or all technical features of the embodiments of the application based on the disclosure of the present invention to enhance the implementation flexibility of the present invention.
[0027] 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 thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures. | A method of processing secure services is provided. The method is applied to a processing unit of a computing device to control the processing unit to process multiple secure services. The computing device includes a storage unit. The method includes: controlling a core of the processing unit to perform following steps in a secure mode: accessing the storage unit to obtain a first command that includes first secure service information, processing a first secure service associated with the first secure service information according to the first command, and accessing the storage unit to obtain a second command that includes second secure service information. During a period from a time point that the core accesses the storage unit to obtain the first to a time point that the core accesses the second command, the core is controlled to stay in the secure mode. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation of international application No. PCT/CA98/00714 filed Jul. 23, 1998 entitled METHOD AND APPARATUS FOR CONTROLLING A WORK IMPLEMENT which designates the United States of America and which is itself a continuation in part of and claims priority from pending U.S. application Ser. No. 08/899,468 filed on Jul. 23, 1997 and entitled METHOD AND SYSTEM FOR CONTROLLING MOVEMENT OF A DIGGING DIPPER, now U.S. Pat. No. 6,025,686.
FIELD OF THE INVENTION
This invention relates to control systems for controlling the motion of work implements, such as the booms of backhoes, feller bunchers, log loaders, excavators, and other machines having articulated arms. The invention relates specifically to methods and apparatus which allow the operator of a work implement to control the work implement by way of a user interface.
BACKGROUND
Modern work implements, such as the articulated arms of backhoes, excavators, feller bunchers, cranes, and the like can be moved with several degrees of freedom. For example, a backhoe arm may comprise a boom pivotally mounted to a vehicle at a first joint, a stick pivotally mounted to the end of the boom at a second joint and a bucket pivotally mounted at the end of the stick at a third joint. Actuators are coupled between the various members which make up the arm. The actuators may be used under the control of an operator to adjust the position of each of the pivoting joints. The operator guides the operation of the work implement by manipulating several controls. The controls may be levers, joysticks, foot pedals and the like. The operator's inputs to the controls affect the direction and speed of motion of the work implement.
The control systems for work implements are generally not completely intuitive. An operator must have much practice before he or she can reliably use the control system to control the work implement accurately. Further, even an experienced operator can readily become fatigued because current control systems require significant concentration by the operator. A fatigued operator is more likely to make mistakes than a well-rested operator. When the work implement is a large powerful machine, such as an excavator or a large backhoe, mistakes can cause great damage to the work implement itself or to surrounding machines or structures.
Various prior patents describe control methods or control systems for work implements which attempt to provide an intuitive interface to an operator. For example, Canadian patent No. 1,330,584 describes a control system which determines how to move the articulated arm of a robot so that an endpoint of the arm is moved to a target point. The method involves generating a pseudo-inverse Jacobian matrix. The method has the problem that the arm does not follow a desired trajectory as accurately as would be desired. Further, devices according to the invention tend to be very finicky to maintain.
Allen et al. U.S. Pat. No. 5,160,239 discloses another control system for a backhoe or the like.
Industrial robots are used for various tasks in industry. Such robots are programmed in advance to guide work implements along predetermined paths. Various methods have been developed to allow such robots to follow the desired predetermined paths under changing conditions accurately. These methods are not generally applicable for use in machines operated by human operators because, in general, the work implements of such machines must follow paths which are not predetermined.
There is a continuing need for a control system for work implements which provides a human operator with intuitive control over the work implement and allows the operator to accurately guide the work implement along a desired trajectory with minimum effort.
SUMMARY OF INVENTION
This invention provides a method for computing in real time a trajectory for a work implement from an operator's inputs to a control member, a method for controlling the velocity of a work implement in an intuitive way, and a method for tuning the operation of a controller for a hydraulically operated work implement. These three main aspects of the invention may be used individually or in any combination. Preferably these three aspects are provided together. The invention also provides apparatus incorporating each of these three aspects individually and in combination.
Accordingly, one aspect of the invention provides a method for controlling a work implement. The work implement typically comprises an articulated arm, as is found on a backhoe or feller buncher. The method includes receiving an input signal from a control and, in real time, computing a desired trajectory from the input signal. The method controls the work implement to move along the trajectory. The step of computing a desired trajectory comprises repeatedly: determining an actual position of the work implement; from the actual position computing a path point which is on, but not at an end of, a previously computed portion of the trajectory; and, adding a continuation of the trajectory to the path point. This method provides built-in positional feedback. Preferably the path point is a point on the previously computed trajectory nearest to the actual position.
The first aspect of the invention also provides a method for controlling a work implement. The method comprises: providing a control member accessible to an operator of the work implement, the control member controllably displaceable by an operator from a neutral position to produce control signals indicating a first direction and a first magnitude; displacing the control member from the neutral position; providing the control signals to an input of a controller, providing to the controller one or more transducer signals identifying a current configuration of the work implement; in the controller: computing a desired path for the work implement, the desired path comprising a sequence of desired positions by: A) periodically sampling the control signal and the transducer signal; B) for each sample computing a desired direction and a desired velocity of the work implement from the control signal; and, C) for each sample extending the desired path by computing a new desired position, the new desired position obtained by determining on the desired path a path point which is closest to an actual position of the work implement and adding a vector to the path point, the vector having the desired direction and a length proportional to the desired velocity; and, generating controller output signals at the processor output to operate the actuators so as to move the work implement in a direction from the actual position to the new desired position with a velocity proportional to the distance between the actual position and the new desired position; and, applying the controller output signals to actuators on the work implement to actuate the actuators to move the work implement.
A second aspect of the invention provides a method for controlling a work implement. The method comprises: providing a control member accessible to an operator of the work implement, the control member controllably displaceable by an operator from a neutral position; displacing the control member from the neutral position in a first direction relative to a reference axis through a distance equal to a first fraction of a distance between the neutral position and a maximum displacement of the control member in the first direction; providing a control signal representing the displacement of the control member at an input of a controller, the control signal identifying at least the first direction and the first fraction; providing to the controller one or more transducer output signals identifying a current configuration of the work implement; in the controller, computing a maximum velocity the work implement in a desired direction of motion corresponding to the first direction; computing a desired velocity of the work implement, the desired velocity proportional to the first fraction multiplied by the maximum velocity; and, generating controller output signals at the processor output corresponding to the desired direction and the desired velocity; and, applying the controller output signals to actuators on the work implement to cause the actuators to move the work implement in the desired direction at the desired velocity. Preferably the desired direction is generally parallel to the first direction.
A third aspect of the invention provides a method for tuning the performance of a control system for a hydraulically operated work implement. The implement comprises one or more actuators and one or more controlled valves associated with each actuator. The method comprises repeatedly in subsequent periods generating control signals to open one or more of the valves by amounts computed to achieve a desired flow rate in each valve. The method includes measuring an actual flow rate at each valve during a period; for each valve, comparing the actual flow rate to the desired flow rate for the period to yield an error value; and, using the error values to correct the calculation of control signals in subsequent periods.
Preferably measuring the actual flow rate in each valve comprises monitoring a signal from a position transducer coupled to the actuator associated with that valve and computing a flow rate at the valve from a change in the transducer signal. Most preferably generating the control signals comprises maintaining a look up table for each valve. The look up table has a plurality of data values for the valve. The data values relate a magnitude of the control signal for the valve to flow in the valve. The method uses the look up table to provide a control signal magnitude corresponding to a desired flow rate.
The invention also provides a control system for a work implement comprising an articulated arm the control system includes a control member accessible to an operator of the work implement. The control member, which is preferably a joystick movable in 3 dimensions, is controllably displaceable by an operator from a neutral position in a desired direction through a desired fraction of a maximum displacement distance. The control member produces a control signal. The control system also has two or more angular position transducers, one of the transducers coupled to each of two or more pivoting joints on the articulated arm, the transducers producing transducer signals representing a current configuration of the articulated arm. A controller is connected to receive the control signals and the transducer signals. The controller comprises: means for computing a desired velocity from the control signal; vector computation means for computing from the desired velocity a vector to be added to a previously computed trajectory; path point computation means for computing from the transducer signal a path point on the previously computed trajectory closest to an actual position of the arm; vector addition means for extending the previously computed trajectory by adding the vector to the path point; and, control means for operating actuators associated with the joints to move an endpoint of the arm along the extended trajectory.
The invention further provides a control system for a work implement comprising two or more movable coupled members and a number of actuators for moving the coupled members relative to one another. The control system comprises: one or more operator controls collectively having at least two degrees of freedom, the controls manipulable by an operator of a work implement to produce first and second output signals indicating a degree of displacement of the controls from a neutral position toward a maximum displacement; one or more transducers coupled to the work implement, the transducers producing transducer output signals representing relative positions of the coupled members; a processor connected to receive the first and second output signals and the transducer output signal. The processor has an output and is adapted to: i) compute a desired direction of motion from the first and second output signals; ii) compute a maximum velocity of the work implement in the desired direction of motion from the transducer output signals; and, iii) generate controller output signals at the processor output to actuate the actuators to move the work implement in the desired direction at a calculated velocity wherein the ratio of the calculated velocity to the maximum velocity is generally proportional to a ratio between the displacement of the controls to the maximum displacement the processor output is coupled to apply the controller output signals to the actuators. The invention may also be provided in the form of a controller for a work implement or computer software for running in the processor of a controller for a work implement.
BRIEF DESCRIPTION OF DRAWINGS
Drawings which illustrate specific embodiments of the invention, but which should not be construed as restricting the spirit or scope of the invention in any way are attached. In the drawings:
FIG. 1 is a side elevational view of a prior art backhoe to which the methods and apparatus of the invention may be applied;
FIG. 2 is a schematic view of the backhoe of FIG. 1;
FIG. 3 is a schematic view of a control joystick and a joystick frame of reference which may be used to specie a position of the joystick relative to its neutral position;
FIG. 4 is a side elevational view, partly in section, of a joystick of a type preferably for use as a control in this invention;
FIGS. 5 and 6 are respectively side elevational and top plan schematic views which illustrate the preferred relationship of the joystick of FIG. 4 to a seat to be occupied by a person operating a machine controlled by the joystick;
FIG. 7 is a block diagram illustrating the operation of a control system according to the invention;
FIG. 8 is a plot showing a desired trajectory of a work implement according to a simple embodiment of the invention;
FIG. 9A is a plot showing a desired trajectory of a work implement according to a preferred position control embodiment of the invention;
FIG. 9B is a plot showing a desired trajectory of a work implement according to a preferred velocity control embodiment of the invention;
FIG. 10 is a flow chart illustrating a method for tuning the response of the system to accommodate the valves being used;
FIG. 11 is a block diagram illustrating the relationships between modules in software for implementing a preferred embodiment of the invention;
FIG. 12 is a flow chart illustrating the overall operation of software running in a processor in a preferred embodiment of the invention;
FIG. 13A, 13B and 13C are respectively functional diagrams of control arrangements implementing position control, velocity control and combined position and velocity control according to the invention; and,
FIG. 14 is a functional diagram of a servo module for use in the invention.
DESCRIPTION
1. Hardware Environment
This invention will now be described using a typical backhoe as an example. An example of the application of some aspects of the invention to the operation of a mining shovel is described in co-pending U.S. application Ser. No. 08/899,468 filed Jul. 23, 1997, the entire text and drawings of which is incorporated herein by reference. FIG. 1 shows a typical backhoe 20. Backhoe 20 has an undercarriage 21 which comprises a pair of tracks 22 mounted on either side of a chassis 23. Tracks 22 extend parallel to the longitudinal axis 26 of chassis 23.
A superstructure 24 is rotatably mounted to chassis 23. Superstructure 24 is mounted to chassis 23 by a ring bearing 30. Ring bearing 30 allows superstructure 24 to be rotated about a superstructure axis of rotation 33 as indicated by arrow 33A by a suitable actuator 34. Actuator 34 might, for example, comprise a pinion gear driven by a hydraulic motor on superstructure 24 and engaged with a ring gear connected to chassis 23. Backhoe 20 has an arm 41 comprising a boom 40 which is pivotally attached to superstructure 24 at a joint 42.
FIG. 2 schematically illustrates the angles which define the configuration of arm 41 of backhoe 20 at any given time. The elevation of boom 40 is controlled by a hydraulic cylinder 44. The position of hydraulic cylinder 44 sets angle θ 1 (FIG. 2). A stick 48 is pivotally connected to boom 40 at a joint 52. The angle θ 2 (FIG. 2) between boom 40 and stick 48 may be adjusted by means of a second hydraulic cylinder 50. A bucket 56 is pivotally connected at the end of stick 48 at a joint 58. The angle θ 3 (FIG. 2) between stick 48 and bucket 56 may be adjusted by means of a third hydraulic cylinder 60.
Backhoe 20 may be considered to have four degrees of freedom. These are angles θ 1 and θ 2 which together adjust the position of the end of stick 48 in the vertical plane of arm 41, angle θ 3 which adjusts the orientation of bucket 56 (i.e. the angle γ of FIG. 2), and the swing angle φ, which may be measured relative to an arbitrary reference line, such as longitudinal axis 26.
Backhoe 20 includes a power source 21 (FIG. 7). Typically power source 21 comprises a diesel engine driving one or more hydraulic pumps. The hydraulic pumps produce a supply of pressurized hydraulic fluid. Valves 81 allow the supply of pressurized hydraulic fluid to be selectively connected to actuators, such as actuator 34 and hydraulic cylinders 44, 50 and 60. In some cases, power source 21 could be a source of electrical power. In such cases, actuator 34 and hydraulic cylinders 44, 50 and 60 would be replaced with electrical actuators and valves 81 would be replaced by electrical switches.
As shown in FIG. 2, The position of a point 65 at the tip of bucket 56 may be specified in a cylindrical frame of reference F arm centred on axis 33. In this frame of reference, the position vector p of point 65 may be specified in terms of the coordinates r, z and φ, as shown in FIG. 2. In the alternative, the position of point 65 relative to superstructure 24 may be specified by the coordinates x, y, and z in a Cartesian coordinate system F boom . F boom is oriented such that arm 41 lies in the x-z plane. It can be appreciated that, in either coordinate system, p is a function of the angles θ 1 , θ 2 and θ 3 and of the lengths of boom 40 stick 48 and bucket 56. By varying the angles θ 1 θ 2 and θ 3 , point 65 may be placed anywhere in a two dimensional "envelope" in a vertical plane passing through boom 40 and stick 48. Bucket 56 may be oriented at any desired orientation, γ. The outer limits of the envelope are determined by the length L 1 of boom 40, the length L 2 of stick 48, the length L 3 of bucket 56, the offset distance D between joint 42 and axis 33 and the ranges of motion of joints 42, 52 and 58.
The angle φ may be changed by rotating superstructure 24 about axis 33. By varying the angles φ, θ 1 θ 2 and θ 3 point 65 may be placed at any desired position within a three dimensional "spatial envelope" surrounding axis 33 with bucket 56 at any desired orientation.
Various types of control may be used by an operator to provide input to the control system of the invention. It is highly preferable that the controller should provide a single control member which is movable by an operator in at least two dimensions. Very preferably the control member is movable in at least three dimensions. Most preferably the control member is movable in four dimensions. Preferably the control member is movable in a plane which appears to the operator of machine 20 to be parallel to the plane of motion of arm 41.
In non preferred embodiments of the invention the control might comprise two or more control members which can be manipulated by an operator and collectively have at least two degrees of freedom. The control produces output signals representative of the position of the control member, or control members, in each of the two degrees of freedom. The output signals, which may be called "control signals", may be combined into a single control signal which represents the position of the control member or members in two or more degrees of freedom.
The operation of this invention will be described with reference to a joystick 70 as illustrated in FIG. 3. Joystick 70 is located next to a seat 69 (FIGS. 5 and 6) for an operator of machine 20 and comprises a handle 71 which is supported in a way that permits it to be moved along three independent axes relative to a neutral position shown in FIG. 3 in dotted outline. Preferably, handle 71 can also be rotated through an angle Γ about a horizontal axis 78 relative to a neutral orientation so that joystick 70 allows an operator to control arm 41 in four degrees of freedom by manipulating a single control member (handle 71).
When handle 71 is in its neutral position, a reference point on handle 71 is at a location 73. An example of a type of joystick suitable for use with this invention is the COORDINATOR™ joystick available from RSI Technologies Inc. of Victoria, British Columbia, CANADA.
The position of handle 71 may be specified in a Cartesian coordinate system F joystick which is fixed relative to superstructure 24 and has its origin at point 73. The following directions of joystick deflection may be defined: "X" direction--positive forward, negative backward; "Y" direction--positive to left, negative to right; "Z" direction--positive upward, negative downward. The rotation of handle 71 about axis 78 may also be specified by the angle Γ.
The vector j=[j x , j y , j z ] can be defined as the deflection of handle 71 relative to point 73 as measured in the frame of reference F joystick . That is, j x is the "X" component of the deflection of handle 71, j y is the "Y" component of the deflection of handle 71, and, j z is the "Z" component of the deflection of handle 71. F joystick should be oriented such that its "X" direction is parallel to the x direction of the frame of reference F boom and its "Z" direction is parallel to the z direction of F boom . Each of j x , j y , and j z has a maximum value which depends upon the construction of joystick 70.
As shown in FIG. 4 joystick 70 has a housing 74 extending along a reference axis 75. Handle 71 is mounted on a rod 76 which protrudes from housing 74. Handle 71 is capable of being moved along the "X" axis of F joystick (left/right as viewed in FIG. 4 and out/in as viewed by an occupant of seat 69). Handle 71 is also capable of being moved along the "Z" axis of F joystick (up/down as viewed in FIG. 4 or as viewed by an occupant of seat 69). Most preferably, handle 71 is also capable of being moved along the "Y" axis of F joystick . The "Y" axis extends perpendicular to the drawing page in FIG. 4 and side-to-side as viewed by an occupant of seat 69. Motion of joystick 70 on the "Y" axis may be used to control the swing of superstructure 24 about axis 33. Joystick 70 has a detent spring 77 which lightly retains handle 71 in its neutral position (i.e. in the position where the Y and Z components of vector j are 0).
One possible construction of joystick 70 is shown in FIG. 4. Joystick 70 has a carriage 110 slidably mounted to guide bars 109 by linear bearings 111. Carriage 110 may be slid in a direction parallel to reference axis 75 by moving handle 71 forward or backward in its X direction which, in FIG. 4 is coincident with reference axis 75. The displacement of carriage 110 along guide bars 109 is measured by a first position transducer 105. Transducer 105 comprises a magnetic pickup device 107 which moves between a pair of bar magnets (not shown) which are affixed to housing 74. Transducer 105 produces an output signal, for example, a first output voltage having a magnitude which varies with the displacement of handle 71 along the "X" axis.
Joystick 70 also has a second position transducer 113 comprising an induction pickup assembly 115 which moves with respect to what is referred to as a second head 117 when handle 71 is moved in the "Z" direction. Transducer 113 produces a second output signal, for example, a second voltage having a magnitude which varies as a function of the deflection of handle 71 along the "Z" axis from point 73.
Most preferably, joystick 70 comprises a third position transducer 119 which comprises an assembly that moves with respect to a third head 121 when handle 71 is displaced along the "Y" axis. Third transducer 119 produces a third output signal, for example, a third voltage having a magnitude which varies as a function of the deflection of handle 71 along the "Y" axis from point 73. The third output signal may be used to control the swing of machine 20 about axis 33.
Most preferably joystick 70 also comprises a fourth sensor which produces a fourth output signal which varies as a function of the angle Γ of handle 71. The fourth output signal may be used to control the pitch angle γ of bucket 65.
Joystick 70 is coupled to a control circuit 80. By moving joystick 70 an operator causes joystick 70 to provide a new value of the vector j to control circuit 80. Control circuit 80, in turn, operates actuators 34, 44, 50, and 60 so as to move arm 41 of backhoe 20 to a desired configuration. Where the actuators are hydraulically operated actuators, control circuit 80 operates valves 81 which regulate the supply of hydraulic fluid to the actuators.
FIG. 7 is a functional block diagram of control circuitry in machine 20. Angular position transducers 86A, 86B, 86C, and 86D (collectively 86) are respectively connected to measure the angles φ, θ 1 , θ 2 and θ 3 . Transducers 86 communicate with controller 80 through an interface 84. Transducers 86 may measure their respective angles directly or may provide controller 80 with outputs from which the angles in question may be derived. For example, angle θ 1 is uniquely related to the length of hydraulic cylinder 44. While it is not preferred, transducer 86B could measure the extension of cylinder 44 instead of directly measuring angle θ 1 . Transducers 86 provide transducer signals to controller 80. The control signals specify the configuration of arm 41.
As noted above, joystick 70 is connected to controller 80 through a suitable interface 88. An operator can move handle 71 of joystick 70 to command controller 80 to move point 65 on arm 41 in a desired direction and speed. Controller 80 processes the operator's input, as described below, and actuates valves 81A, 81B, 81C and/or 81D (collectively valves 81) through an interface 85 in order to cause arm 41 to move in the specified manner. Valves 81 are typically electrically operated valves. The rate of fluid flow through each of valves 81 being adjustable by varying the voltage used to actuate the valve. The actual flow rates through each valve 81 may be monitored by flow rate meters (not shown).
Controller 80 preferably comprises a computer processor 94 running a suitable real time operating system. Processor 94 runs computer software 95 which causes processor 94 to monitor the input from joystick 70, and the inputs from transducers 86. Processor 94 computes a path to be followed by point 65, computes the voltages necessary to be applied to valves 81 to cause point 65 to follow the desired path, applies the computed voltages to valves 81 through interface 84 and monitors the progress of point 65. The overall operation of processor 94 under the control of software 95 according to one embodiment of the invention is summarized in FIG. 12.
2. Achieving Maximum Velocity
It is desirable that the velocity of point 65 should be directly related to the deflection of handle 71. That is, the direction of motion of point 65 should be parallel to the direction of deflection of handle 71. Also, if handle 71 is deflected away from point 73 by only a small distance then point 65 should move slowly. The speed of point 65 should increase as the distance of deflection of handle 71 from point 73 is increased by an operator. This provides the operator with an intuitive way to control the operation of backhoe 20. The operator simply moves handle 71 in the same direction that he or she wishes point 65 to move. The operator can regulate the speed of point 65 by adjusting the distance of handle 71 from its neutral position 73.
Software 95 in controller 80 receives inputs from joystick 70 (step 1210). These inputs include at least the magnitudes of the first and second signals which correspond to the "X" and "Z" deflections of handle 71 from point 73. Most preferably these inputs also include signals which correspond to the "Y" and "I" deflections of handle 71. From these received signals, software 95 can calculate the desired direction of motion of point 65 on arm 41 (step 1212).
Most preferably, the motion of point 65 is governed by the following equations: ##EQU1## In these equations d/dt represents the derivative with respect to time, ν max is a variable function which provides the maximum instantaneously available velocity of point 65 in the specified direction φ max is the maximum swing speed about axis 33 and γ max is the maximum available change in the pitch angle of bucket 56 for the current configuration of arm 41. γ max is a function of the current rotational speeds of joints 42 and 52 as well as the maximum rotational speed of joint 58. In equations (1) through (4) it is assumed that j x x, j y , j z and Γ are all scaled to lie in the range of -1 to 1 so that, for example, when handle 71 is maximally deflected in the positive x direction, j=1. ν max depends, in general, upon the particular geometry of backhoe 20 as well as the current configuration of backhoe 20.
This provides significant advantages over prior art control systems in which the equations of motion are as follows: ##EQU2## where V max is a constant equal to the maximum linear velocity of point 65. Such prior art systems ignore the fact that the maximum linear velocity of point 65 will vary from time to time depending upon the configuration of arm 41, the direction of motion, and upon present conditions affecting the actuators responsible for moving the various parts of arm 41.
In such prior art systems there will be many circumstances where the maximum instantaneously available linear velocity of point 65 in the desired direction will be significantly less than V max . This makes it more difficult for an operator to control the motion of arm 41. Consider, for example, a situation where, because of the configuration of arm 41, it is only possible to move point 65 in the direction of increasing r t at a speed of 1/2V max . An operator might move handle 71 in the X direction in order to cause point 65 to move in the positive X direction with a speed determined by equation (4). The speed of point 65 will be increased as the operator pushes handle 71 farther in the positive X direction. This will continue to happen until handle 71 is moved half way toward its maximum deflection in the "X" direction. At this point, point 65 will be moving at a speed of 1/2V max according to equation (4). Further deflection of handle 71 in the positive "X" direction will have no effect on the motion of point 65 as point 65 is already moving as fast as it can move.
For any particular construction of arm 41, ν max will be a function of the lengths of the various segments of arm 41, the current configuration of arm 41 (i.e. the current values of θ 1 , θ 2 and θ 3 ), the maximum rotational speeds of the joints of arm 41 and the direction of travel. That is, in general ν max =f(L 1 , L 2 , L 3 , θ 1 , θ 2 , θ 3 , dθ 1max /dt, dθ 2max /dt, j x , j z ). The maximum rotational speeds of joints 42 and 52 may also depend upon the configuration of arm 41 and the hydraulic flow available. Processor 94 may monitor hydraulic system pressure and/or other indicators of the hydraulic flow available.
For example, when arm 41 has a geometry as shown in FIG. 2 then ν max will be limited either by the maximum rotational speed of joint 42 or by the maximum rotational speed of joint 52. It can be shown that ν max is given by the lesser of: ##EQU3## and, ν max is given by the lesser of: ##EQU4##
Software 95 measures the actual configuration of arm 41 (step 1214). The configuration of arm 41 is related to the position of point 65 by the forward kinematics for arm 41 which are one or more equations relating the angles θ 1 , θ 2 and θ 3 to the position of point 65.
Software 95 then computes ν max (step 1220). The relationship between ν max , the configuration of arm 41 and the desired direction of motion of point 65 (as specified by the position of handle 71) is programmed into software 95 so that program controller 80 can calculate ν max for the current values for the position and desired direction of motion of point 65. From ν max controller 80 can compute the desired velocity of point 65 from equations (1), (2) and (3) (step 1222).
3. Trajectory Control
As noted above, the desired direction of motion of point 65 is determined by the direction of deflection of handle 71 as indicated by the vector j according to equations (1), (2) and (3). These equations define the instantaneous desired velocity of point 65. Taken over time, these equations define a trajectory through space along which the operator of machine 20 wishes point 65 to move. This trajectory is independent of the geometry of machine 20. The trajectory is not known in advance but is determined as machine 20 is operated by the way that the operator moves handle 71 (steps 1224).
In general, point 65 will not be able to exactly follow the desired trajectory. As controller 80 operates valves 81 the resulting motions of arm 41 will not be exactly the same as the desired motions calculated by controller 80. These errors will cause point 65 to deviate from the desired path. Controller 80 should compensate for these errors.
As noted above, controller 80 typically incorporates a digital computer processor 94. Processor 94 typically runs software 95 which frequently, with a sample period Δt samples the inputs from joystick 70 and transducers 86. For each set of samples, processor 94 calculates the desired trajectory of point 65 and computes the desired positions and velocities for the actuators which move point 65. Preferably Δt is in the range of about 1 millisecond to about 100 milliseconds.
In a simple embodiment of the invention the desired trajectory of point 65 may be considered to be a series of line segments δp i in the r-z plane of arm 41 as shown in FIG. 8. In each sample period a new line segment is determined from the position of joystick 70. The position of joystick 70 specifies the desired velocity of point 65 during the next sample period. The length of the line segment is determined by both the desired velocity and the length of the interval between samples. That is,
δp.sub.i =j.sub.i ν.sub.max Δt (15)
It can be seen that the desired position of point 65 after a number of sample periods is simply the starting position of point 65 plus the vector sum of all line segments δp i for each of the intervening sample periods. In other words, the desired position at any time is the integration of the desired velocity, as specified by an operator of machine 20 up to that time.
This simple method of trajectory generation, which is used in some prior art systems, has the shortcomings that it does not provide any feedback to correct errors in position. This lack of feedback can lead to non-intuitive behaviour of arm 41. For example, a rock or a tough patch of dirt in the path of bucket 56 may stop bucket 56 from moving. However, the desired position of point 65 continues to move. The distance between the desired position of point 65 and its actual position can therefore become very large. If the rock or patch of dirt finally yields to bucket 56 then controller 80 will cause point 65 to suddenly accelerate to catch up to the desired position. This can be disconcerting for an operator of machine 20.
Better methods for generating trajectories in the apparatus and methods of this invention are shown in FIGS. 9A and 9B. FIG. 9A shows a method which may be called a "position control" method because it computes a desired position for point 65. FIG. 9B shows a method which may be called a "velocity control" method because it computes a desired velocity for point 65.
In the position control method of FIG. 9A, for each sample period, the increment δp i to the trajectory is computed from the position of joystick 70 as above. However, instead of adding each increment to the end of the previous increment, each increment is added to a point on the previously calculated portion of the trajectory which is closest to the actual position of point 65. This seemingly simple alteration provides very significant improvement to the operation of machine 20. The inventors have discovered that computing the continuation of a trajectory by adding a vector to a calculated point along a previously computed trajectory instead of simply adding a vector to the endpoint of a previously computed trajectory provides positional feedback in a control system which compensates for off-path errors as described above.
In FIG. 9A the symbol P path ,i is the point on the desired trajectory which is closest to the actual position of point 65 at the i th sample time, p dsr ,i is the desired position of point 65 at the i th sample time as calculated at the i-l th sample time and p act ,i is the actual position of point 65 at the i th sample time.
At each sample time, the p path ,i is calculated (step 1226) from the position p act ,i and the previously calculated value of p dsr ,i p act ,i can be computed from the angular positions measured by transducers 86 by means of the kinematic equations which relate the angles of joints 42, 52, and 58 to the position of point 65 in the r-z plane. p path ,i can be calculated as follows:
p.sub.path,i =P.sub.path,i-1 +sδP.sub.i-1 (16)
where ##EQU5## the desired position p dsr ,i is then calculated (step 1230) from
p.sub.dsr,i =p.sub.path,i +δp.sub.i (18)
Most preferably, instead of calculating δp i from equation (15), δp i is computed as follows:
δp.sub.i =T.sub.lead j.sub.i ν.sub.max (19)
Equation (19) is the same as equation (15) with the exception of the parameter T lead . T lead may be adjusted to match the time which machine 20 takes to respond to inputs. T lead is preferably several times larger than the sample time At. In a typical hydraulic excavator, T lead is preferably in the range of about 200 milliseconds to about 1000 milliseconds.
When the desired position P dsr ,i is known then controller 80 can calculate the voltage to apply to open each of valves 81 (step 1234) to move point 65 from its current location p act ,i to the desired position in time T lead . This is done by using inverse kinematic equations to determine how much each of joints 42, 52 and 58 must move to move point 65 to point p dsr ,i in time T lead . The inverse kinematic equations are the inverse of the equations which specify the position of point 65 as a function of the positions of joints 42, 52 and 58. As such, the inverse kinematic equations will be specific to the geometry of each work implement. The inverse kinematic equations may be solved numerically in processor 94 using standard techniques.
The velocity at which each joint must move may be readily obtained by dividing the computed amount of joint motion by T lead . The velocity of each joint depends upon the rate at which hydraulic fluid is allowed to flow into the actuator for that joint. The rate of hydraulic fluid flow is controlled by valves 81 which are, in turn, operated by controller 80. Controller 80 sets a voltage level for each valve. Interface 84 applies the computed voltage to each valve (step 1236). Preferably controller 80 has access to a function or a group of functions which, given a desired speed for a joint, returns the voltage level necessary to operate the specified joint at that speed. The function may, for example, access a lookup table 92 which specifies the necessary voltages for several speeds for each joint.
Typically each valve 81 has a separate coil which actuates the valve to allow fluid flow in each direction. Each valve may therefore behave differently for each direction of flow. Therefore, lookup table 92 preferably comprises separate sections for flow through each valve 81 in each direction.
Most preferably voltages are not set directly based upon values in table 92 because this could result in jerky behaviour. Instead, voltages are ramped toward their desired values. Controller 80 preferably allows ramping at different rates for increasing and decreasing voltages. This may be accomplished by providing stored parameters accessible to controller 80 which specify maximum amounts of voltage increase or voltage decrease for each sample period.
FIG. 13A is a functional diagram of a control system which implements position control. In FIG. 13A, a signal representing the vector j and a signal representing the current configuration of arm 41 are supplied to means for calculating ν max indicated by 1310. Means 1310 produces a signal representing a desired velocity which is provided to a vector computation means 1314. Vector computation means 1314 computes the vector δp i which will be added to the previously calculated portion of the trajectory to yield a new desired position p dsr . Vector δp i is preferably calculated by multiplying by the time constant T lead . The signal representing the current configuration of arm 41 is also processed by forward kinematic computation means 1318 to yield a signal p act representing the actual position of reference point 65 on arm 41. This signal is processed by means 1316 which computes a vector p path pointing to the point on the previously computed portion of the trajectory which is closest to the position indicated by p act . The computed vector δp i is added to p path at vector summing node 1319. To yield a signal indicating the desired position. This signal is processed by inverse kinematic computation means 1320 to yield a desired configuration for arm 41. The actual configuration is subtracted from the desired configuration at vector subtraction node 1322 to yield a result which is divided by Tl ead at divider 1324 to provide a signal representing the desired rotational speed of each joint in arm 41. A signal representing the desired angle of each joint in arm 41 may be optionally taken at the output of inverse kinematic computation means 1320 as indicated by the dashed line in FIG. 13A.
FIG. 9B illustrates an alternative "velocity control" implementation of the invention. As in the position control implementation of FIG. 9A, the desired trajectory is arrived at by adding δp i to a calculated point p path ,i on the previously calculated trajectory. p path ,i is calculated as described above.
In a velocity control implementation of the invention processor 94 calculates a desired velocity ν dsr such that:
P.sub.close =P.sub.act,i +ν.sub.dsr T.sub.close (20)
where T close is a parameter that is related to the time constant within which the actual position of point 65 should converge to the desired path. In a typical hydraulic excavator T close is typically chosen to be in the range of about 1 second to about 5 seconds. Processor 94 then computes the control signals to be applied to valves 81 to achieve the desired velocity. This is done using the inverse of the Jacobian matrix for arm 41. The Jacobian function specifies the relationship between the velocity of point 65 in F boom and the angular velocities of joints 42, 52, and 58. Methods for deriving the Jacobian for a particular configuration of arm 41 and for determining the inverse Jacobian are well known to those skilled in the art and are therefore not described herein.
FIG. 13B is a functional diagram of a control system which implements velocity control. In FIG. 13B, a signal representing the vector j and a signal representing the current configuration of arm 41 are supplied to means for calculating ν max indicated by 1310. Means 1310 produces a signal representing a desired velocity which is provided to a vector computation means 1314. Vector computation means 1314 computes a vector δp i . Vector computation means 1314 preferably multiplies its input by the parameter T lead . The signal representing the current configuration of arm 41 is also processed by forward kinematic computation means 1318 to yield a signal p act representing the actual position of reference point 65 on arm 41. This signal is processed by means 1316 which computes a vector p path pointing to the point on the previously computed portion of the trajectory which is closest to the position indicated by p act . The vector p err is computed at subtraction node 1328. This vector is then divided by T close at dividing means 1332. The resulting signal is added to the desired velocity at vector summing node 1334 to yield a signal ν dsr representing the desired velocity of reference point 65. ν dsr is processed by an inverse Jacobian computation means 1336 to yield an output signal specifying the desired velocities of each of joints 42 and 52. A signal representing the desired positions of each joint 42 and 52 may optionally be derived by multiplying the output signal by T lead at multiplier 1340 and adding the result to the actual position of point 65 at summing node 1342 as indicated by the dashed lines in FIG. 13B.
Either position control, velocity control or a combination of position control and velocity control may be used in any given situation. As shown in FIG. 13C, position control and velocity control may be combined. In general, it is preferable to use position control in situations where the inverse kinematics are easier to compute than the inverse Jacobian and it is preferable to use velocity control in cases where the inverse Jacobian is easier to compute than the inverse kinematics.
4. Speed-Precision Control
The value of ν max is not necessarily the maximum velocity of motion of point 65 in a given direction which it is physically possible to achieve in machine 20. If boom 40 and/or stick 48 were allowed to move at their maximum possible velocities then the motions of arm 41 would likely not be smooth. In an extreme case, arm 41 could be subjected to excessive wear. Preferably controller 80 contains a set of parameters 97 which place constraints on the allowed motions of arm 41. Parameters 97 may include, for example, parameters which specify: the maximum allowable velocity of boom 40 about joint 42; the maximum allowable velocity of stick 48 about point 52; the maximum allowable velocity of point 65 relative to superstructure 24; the maximum allowable acceleration of point 65; the maximum allowable deceleration of point 65; and the size of the region near the limits of travel of any joint in which motion of that joint will be decelerated as the joint moves toward its limit. This last parameter may be specified as a time interval such that deceleration will begin to occur regardless of the operators input to joystick 70, if, at the current speed the joint will reach the end of its travel during the time interval. Controller 80 will begin to slow the motion of the joint in question earlier as this last parameter is increased.
Parameters 97 may also include parameters which specify how accurately point 65 follows a desired path. These parameters include T lead and T close . It can be appreciated that the behaviour of machine 20 can be significantly altered by changing parameters 97. If the operator is less experienced then parameters 97 may be set to keep the maximum speeds of point 65 and the individual components of arm 41 relatively low. This will reduce the likelihood that the operator will inadvertently operate machine 20 in a way that might cause damage to machine 20 itself or to surrounding structures. If the operator is more experienced then a set of parameters 97 which allows greater maximum speeds may be used.
In a preferred embodiment, machine 20 includes a non-volatile memory 99 accessible to controller 80 which contains several alternative sets of parameters 97. Controller 80 includes a switching means 98, such as an electrical switch, a touch screen, a keyboard, a pointing device, or the like, which an operator of machine 20 can use to select one of the alternative sets of parameters 97. In this manner the operator may choose a trade-off between high speed and less smoothness of operation on the one hand and lower speed and smoother operation, on the other hand, which is appropriate to the operator's skill level and to the job at hand.
Instead of providing a separate set of parameters 97 for each possible position of switching means 98 it may be desirable to provide sets of parameters 97 only for a few positions of switching means 98. When switching means 98 is set to a position for which a set of parameters 97 has not already been specified then controller 80 can construct a suitable set of parameters by interpolating between the two closest sets of parameters stored in the non-volatile memory 99.
5. Valve Tuning
One disadvantage of prior controllers of the general type described herein is that they are difficult to maintain. This is partly because the relationship between the control voltage applied to each valve and the resulting fluid flow through that valve can be complicated. Two valves of the identical type from the same manufacturer can have voltage-flow characteristics which are different enough from one another that replacing one valve with another, as is periodically necessary in the maintenance of hydraulic machinery, can seriously interfere with the operation of the control system.
The inventors have discovered a method to virtually eliminate this problem. As described above, in a system according to the invention, controller 80 can automatically adjust its operation to adapt to the characteristics of valves 81 (step 1238). To do this, controller 80 receives signals from transducers 86 which indicate the current position of each joint 42, 52 and 58. As noted above, each joint is operated by an actuator. The position of each joint depends upon the amount of hydraulic fluid that has been allowed to flow into the actuator. For example, where the actuator is a hydraulic cylinder then the length of the cylinder increases linearly with the volume of fluid which flows into the cylinder. The position of a joint operated by the cylinder is a function of the length of the cylinder. The function depends upon the geometry of the joint and upon how the hydraulic cylinder is coupled to the joint. The net amount of fluid which has flowed into or out of the cylinder as the joint moves from a first position to a second position can therefore be determined from the geometry of the joint and the two positions.
FIG. 10 is a flow chart illustrating a method for tuning the response of the system to accommodate the valves being used. The method begins when controller 80 calculates a voltage to be applied to a valve 81 as described above (step 210). Controller 80 then applies the calculated voltage to the valve (step 214). The actual rate of flow through any one of valves 81 may be readily be computed in controller 80 (step 216) by calculating the difference between the current position of the joint operated by that valve and a position of the same joint at a recent previous sample time. Controller 80 includes a function which calculates the amount of fluid which would have necessarily flowed into the actuator for that joint in order to cause the observed joint motion. The rate of fluid flow can then be computed from the known time between the samples (step 222).
Controller 80 then computes from the measured flow rate the voltage which should have been required to produce the measured flow rate (step 226). This computation is preferably done using table 92 in the same way that controller 80 calculated the voltage to apply to valve 81 in step 210.
Preferably table 92 comprises a plurality of data values for each valve 81. Each data value specifies the voltage to be applied to that valve 81 to achieve a specified flow rate. The voltage to be applied to the valve 81 for any flow rate intermediate two of the specified flow rates may be obtained by interpolation. Controller 80 can compare the information from its direct computation of the flow through each valve 81 to the desired flow rates to generate a set of errors (step 230) which are used, in turn, to correct table 92.
Table 92 may be corrected by determining an average error for each data point. Controller 80 determines the average error by using table 92 to determine what voltage would have been necessary to achieve the actual measured flow rate. An error sample can then be obtained by subtracting the voltage which, according to table 92, should have been applied to the valve 81 to obtain the observed flow rate from the voltage which was actually applied to the valve 81. Controller 80 accumulates a number of error samples for a range of flows surrounding each data point (step 234). When a suitable threshold number of error samples have been obtained then each data point is updated by calculating an average error for the region surrounding that data point (step 236) and subtracting all or a fraction of the calculated average error from the value of that data point (step 238). The amount of the average error that is subtracted from each data point is preferably a parameter which can be set by a technician to tune the operation of the system. It may be necessary or desirable to reduce the fraction of the average errors which are subtracted from the data values at each update in order to avoid large fluctuations in the data values. What is desired is that the data values should approach a steady state as time passes.
Most preferably the data points in table 92 are associated into groups each containing one or more associated data points for a particular valve 81. Preferably, all data points in each group are updated at the same time after more than the threshold number of error samples have been collected for each data point in the group. For example, if table 92 comprises 7 data points for each direction of each valve 81 then the first data point (which indicates the threshold voltage at which valve 81 just opens) might be in a first group of its own, the next two data points would together comprise a second group and the next three data points would comprise a third group.
In general, it is not necessary to update the value of the final data point (corresponding to the maximum flow) because the maximum voltage that can be applied to any valve will generally be dictated by the design of the valves themselves and the controller 84 which drives them. It is usually not desirable or necessary to automatically update the value of this final data point.
Before updating each data point controller 80 should check to ensure that the value of the updated data point will not exceed the value of any data point corresponding to a higher flow rate and will not be less than the value of a data point corresponding to a lower flow rate. Controller 80 should also check when updating the data point for the lowest flow rate that the new value for the data point will not be less than zero.
Preferably controller 80 performs certain checks before collecting an error sample. An error sample will not be valid near a limit of motion of any joint because the joint cannot move past its limit. Therefore, error samples resulting from measurements at the limits of travel of a joint ought not to be included in the average error. The above noted method of measuring actual flow rates is not valid when the flow through a valve 81 is changing direction. Therefore, any error sample for which the desired flow through a valve is opposite in direction from the measured actual flow through the valve should not be included in the average error. Because there is often a time lag between the initial application of voltage to a valve and the initial motion of the joint actuated by that valve error samples taken in the first instants after a valve is opened should not be included in the average error.
Preferably, the values in table 92 can be saved to non-volatile memory. Then, whenever controller 80 is started it can load table 92 from memory. Some types of non-volatile memory are limited in the number of times that they can be updated reliably with new information. for example, electrically erasable programmable read only memory chips ("EEPROMS") of the type currently commonly available can typically be written to on the order of 100,000 writes. Where such types of non-volatile memory are used it is not desirable to update the non-volatile memory too frequently because to do so could result in premature failure of the non-volatile memory.
While the software 95 running in the processor 94 of controller 80 may take various forms it has been found to be convenient to provide software 95 in the form shown in FIG. 11. As shown in FIG. 11, software 95 comprises a number of modules. Module 302 receives sampled inputs from transducers 86 byway of interface 84. Module 302 then stores this information so that it is available to other modules of software 95. Similarly, module 306 receives sampled inputs from joystick 70 by way of interface 84 and makes those results available to coordinated motion control module 308. Module 308 computes the desired positions and velocities of the work implement, as described above, as a function of the inputs received from joystick 70 and transducers 86. Module 312 generates desired flow rates for each function and uses feedback from transducers 86 to control machine 20 to follow the path prescribed by module 308 as closely as possible.
FIG. 14 is a functional diagram of a suitable servo control 312. A separate servo control should be provided for each joint 42 and 52. Servo control module 312 produces a servo output.sup.⊖ servo by summing a number of signals at summing node 1420. A feed-forward signal is provided through block 1412. Block 1412 multiplies its input signal by a gain k F which is typically in the range of 0 to 1. Feedback signals are also derived by subtracting the actual joint rotational speed from the desired rotational speed at subtraction node 1410. One component of the feedback signal is integrated by integrator 1414 and passed through block 1416 multiplies the integrated error by gain k I and passes the result to node 1420. Another component of the feedback signal is passed directly to node 1420 through block 1418 which multiplies the velocity error by gain k D . Positional feedback may be optionally included as indicated in dotted lines in FIG. 14. A position error signal is obtained by subtracting the actual joint position from its desired position at node 1424, passing the result in block 1426 which multiplies the angular error by gain k p and adds the result to the servo signal at node 1420. Various ways to implement servo control module 312 are well known to those skilled in the art and will therefore not be described here. Module 314 calculates desired flow rates for actuators on each joint from the outputs from the servo modules for each joint.
Module 316 takes as input the desired flow for each function and computes the voltages to apply to each of valves 81 to achieve the desired flow. Module 316 preferably limits the rate of change of its output, as described above. Module 318 interfaces to valve driver 85 to apply control voltages to valves 81.
As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof For example, the foregoing description applies the methods and apparatus of the invention to the control of a backhoe. The methods and apparatus of the invention could readily be applied to machines having other types of work implements.
Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims. | A controller for a work implement, such as the arm of a backhoe, a feller buncher, an excavator or the like provides a number of advantages over previous controllers and control methods. The controller responds to an operator's inputs to a joystick control such that the work implement moves parallel to the direction in which the joystick is deflected at a speed which is proportional to the amount of deflection of the joystick. The controller used the joystick position to generate a path and attempts to cause the work implement to move along the path. The controller computes a maximum available speed in the direction of motion specified by the joystick and is self calibrated so that full deflection of the joystick selects the maximum available speed. The controller has a self calibration mode which compensates for variability in the motion produced by the various actuators in response to given control signals. In a hydraulically operated machine the self calibration feature involves measuring actual fluid flow rates by measuring changes in the position of actuators and comparing the measured and actual flow rates to yield an error sample. The controller allows the maximum speeds of various parts of a controlled machine to be limited. | 4 |
TECHNICAL FIELD
This invention relates to a professional looking storage folder for filing important legal and professional work documents, such as wills, tax returns and quarterly financial statements and reports, and in particular to a folder that can expand to accommodate multiple documents, taxpayer records, etc. of archival importance.
BACKGROUND OF THE INVENTION
Tax preparers and accountants will often produce reports for a client to advise them of their current financial condition. It is important to present these reports to clients in a professional and elegant manner to comport with the significance of the financial information. Thus, an attractive and professional appearing report folder in which to present a report is desired.
Quite often, reports will be presented on a quarterly basis, summarizing financials for a given quarter of the year. It is desirable to collect the four quarterly reports for a given year in one folder to provide a complete record for the year. It is also desirable to provide identification on the folder's front and edge to note the year, assuming that it will be placed on a shelf or in a file drawer with previous years reports, in order to distinguish one year from another.
A need exists to provide an elegant, professional looking report folder, particularly one that can hold the four quarterly reports for a given year yet provide fast, easy retrieval of folder contents in future years.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, an expandable folder is provided, comprising a single, integral sheet of material including a back having a lower edge, an upper edge, and first and second side edges, a first side connected to the first side edge of said back by a first expanding side section having first, second and third side fold lines, a second side connected to the second side edge of said back by a second expanding side section having first, second and third side fold lines, a front connected to the lower edge of said back by a expanding lower section having first, second and third lower fold lines, the front having a cover portion and a fold over portion, a flap connected to said upper edge of said back by an expanding upper section having first, second, third and fourth upper fold lines, wherein the fold over portion of said front has a first tab and a second tab, the first side has a slot to receive said first tab, the second side has a slot to receive said second tab, and the cover portion of said front has a slot for receiving said flap.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the invention and its advantages will be apparent from the following Detailed Description when taken in conjunction with the accompanying Drawings, in which:
FIG. 1 is a plan view of an expandable folder forming a first embodiment of the present invention;
FIG. 2A is a perspective view of the expandable folder partially assembled with the sides folded inward;
FIG. 2B is a perspective view of the expandable folder assembled with the flap open to receive documents;
FIG. 2C is a perspective view of the expandable folder assembled with the flap closed; and
FIG. 2D is perspective view of the expandable folder assembled showing the labeling.
DETAILED DESCRIPTION
With reference now the Figures, wherein like reference characters designate like or corresponding parts throughout the several views, an expandable folder 10 forming a first embodiment of the present invention is disclosed. The expandable folder 10 is designed to contain reports, particularly quarterly reports, and can expand to accommodate an increasing thickness of the reports, as will be described here after. Further, the expandable folder 10 can be assembled without the use of glue, or other separate fasteners, and with no special tools.
With reference now to FIG. 1 , the expandable folder 10 can be seen to be formed by a single integral sheet of material 12 . The material 12 is preferably heavy paper, such as 130 pounds stock. The material 12 is formed into a back 14 , a first side 16 , a second side 18 , a front 20 and a flap 22 . The front 20 is connected to a lower edge 24 of the back 14 by an expanding bottom section of the front 20 including three fold lines 26 , 28 and 30 . The first side is connected to a first side edge 32 of the back 14 by an expanding side section including three side fold lines 34 , 36 and 38 . The second side 18 is connected to a second side edge 40 of the back 14 by an expanding side section including three fold lines 42 , 44 and 46 . The flap 22 is connected to a top edge 48 of the back 14 by an expanding top section including four fold lines 50 , 52 , 54 and 56 .
The first side 16 has a tab slot 58 formed therein. The second side 18 has a tab slot 60 formed therein. The front 20 is formed into two sections, a cover portion 62 and a fold over portion 64 separated by a fold line 76 . The cover portion 62 has a flap receiving slot 66 therein. The fold over portion 64 is defined by having tapered tabs 68 and 70 .
With reference to the Figures, the expandable folder 10 can be assembled by folding in the first and second sides 16 and 18 , as seen in FIG. 2A , so that the surfaces 72 of the first and second sides 16 and 18 face away from the inner surface 74 of the back 14 . The front 20 is then folded about the fold lines 26 , 28 and 30 so that the fold line 76 separating the cover portion 62 and fold over portion 64 is proximate the upper edges 78 of the first and second sides 16 and 18 . The fold over portion 64 is then folded about the fold line 76 so that the tabs 68 and 70 are positioned between the first and second sides 16 and 1 and the back 14 , as seen in FIG. 2B . The tab 68 is slid into slot 58 and the tab 70 is slid into slot 60 . The tabs 68 and 70 wedge into slots 58 and 60 due to their tapered wedge shape. By using the tabs 68 and 70 and slots 58 and 60 , the first and second sides 16 and 18 are prevented from opening outward and the front 20 is held in position adjacent to the back 14 to form a pocket to receive the reports.
After the reports have been inserted within the expandable folder 10 , the flap 22 can be folded over the reports and the end 80 of the flap inserted into the flap slot 66 in the front 20 to close the folder 10 over the reports. One advantage of the design is the fact that the fold over portion 64 covers the flap slot 66 when the folder 10 is assembled such that when the end 80 of the flap is inserted into the flap slot 66 , the end 80 is sandwiched between the fold over portion 64 and cover portion 62 so that is does not catch on or interfere with the reports inside the folder 10 . The use of the fold lines 26 – 30 , 34 – 38 , 42 – 46 and 50 – 56 permits the front 20 and back 14 to be spaced apart the proper distance to hold the reports and allows the expandable folder 10 to expand to the thickness required. The use of fold lines 50 , 52 , 54 and 56 define a label section 82 between the fold lines 52 and 54 which can be marked with labels identifying the contents of the expandable folder 10 . By use of the four fold lines 50 , 52 , 54 and 56 , the label section 82 will remain generally parallel the end of the expandable folder 10 as the folder is expanded in thickness to allow the label section 82 to be viewed easily.
In one expandable folder constructed in accordance with the teachings of the present invention, the folder was designed to accommodate a total thickness of reports therein of 1¼ inches. The fold lines 26 , 28 and 30 , fold lines 34 , 36 and 38 , and fold lines 42 , 44 and 46 were each separated by ⅝ inches. The fold lines 50 and 52 and fold lines 54 and 56 were separated by 5/16 inches. The fold lines 52 and 54 were separated by ⅝ inches. The back 14 and cover portion 62 (excluding the bottom section with fold lines 26 – 30 ) were 9⅝ inches high and 11⅝ inches wide. The flap 22 was four inches high (excluding the top section with fold lines 50 – 56 ). The flap slot 66 was 4¾ inches wide. The tab slots were 1¼ inches wide and the first and second sides 16 and 18 were 2½ inches wide (excluding the side sections with fold lines 34 – 38 and 42 – 46 ). The distance from fold line 76 to flap slot 66 is 2 13/16 inches.
As can be appreciated, the expandable folder 10 can be assembled without tools or equipment. No glue or other fasteners are required to assemble the folder 10 . In spite of the lack of glue or fasteners, the expandable folder 10 securely holds the reports in an attractive and presentable manner. The expandable folder 10 will readily fit on a shelf or in a drawer, with the label section 82 readily visible to indicate to the user the contents of the folder 10 and the firm name of the preparer. The exposed surface of the back 14 can also be imprinted with the preparer's firm name and personalized with an label adhered by adhesive to show the recipient's name, contents, year, etc. Preferably, the fold lines are knife cut and not scored. Clearly, if glue or other fasteners are desired, the expandable folder 10 can incorporate them.
While a single embodiment of the present invention has been illustrated in the accompanying drawings and described in the foregoing detailed description, it will be understood that the invention is not limited to the embodiment disclosed, but is capable of numerous rearrangements, modifications and substitutions of parts and elements without departing the scope and spirit of the invention. | An expandable folder ( 10 ) is disclosed for holding reports. The folder ( 10 ) is formed of a single sheet of material ( 12 ). The folder ( 10 ) includes a back ( 14 ), a front ( 20 ), two sides ( 16, 18 ) and a flap ( 22 ). The sides ( 16, 18 ) are folded inwardly and the front ( 20 ) is folded upwardly to form a pocket. Tabs ( 68, 70 ) on the front fit into slots ( 58, 60 ) in the sides ( 16, 18 ) to hold the folder together. Two label sections (label section ( 82 ) and back ( 14 )) are provided to allow the folder to be marked with identifying information. | 8 |
TECHNICAL FIELD
[0001] The present invention relates to an airbelt configured to inflate a bag-like belt with gas from an inflator in order to restrain a vehicle occupant at the time of a vehicle collision or the like, and an airbelt apparatus employing the same. More specifically, the present invention relates to an airbelt and an airbelt apparatus in which a folded body of a bag-like belt is surrounded with a cover, and the folded body and the cover are sewn together with tear seams.
BACKGROUND ART
[0002] Examples of this type of conventional airbelt apparatuses are described in FIG. 6 of Japanese Unexamined Patent Application Publication No. 11-255057, and FIG. 8 of Japanese Unexamined Patent Application Publication No. 2000-203380.
[0003] These are airbelts including a folded body formed by folding a bag-like belt into a belt-like shape, the bag-like belt being to be inflated by introduction of gas, and a cover covering the folded body of the bag-like belt, wherein the folded body and the cover are sewn together with tear seams, and thereby the slip between the two is prevented.
[0004] In such airbelts, the folded body and the cover are sewn together, and the cover does not slip relative to the folded body. The tear seams have such a strength that they tear when the airbelts are inflated.
CITATION LIST
Patent Literature
[0000]
PTL 1: Japanese Unexamined Patent Application Publication No. 11-255057
PTL 2: Japanese Unexamined Patent Application Publication No. 2000-203380
[0007] Japanese Unexamined Patent Application Publication No. 11-255057 does not specifically describe the arrangement of the tear seams.
[0008] In Japanese Unexamined Patent Application Publication No. 2000-203380, the tear seams are provided in the longitudinal direction of the airbelt contiguously in a zigzag manner. In the case where tear seams are contiguously provided as described above, sometimes a high-power inflator (an inflator that generates high-pressure gas) is required in order to increase the pressure of gas from the inflator and to thereby tear the tear seams when the airbelt is inflated.
SUMMARY OF INVENTION
Technical Problem
[0009] An object of the present invention is to provide an airbelt wherein a folded body of a bag-like belt is covered with a cover, and the two are sewn together with tear seams, and wherein the tear seams can be torn without the need to use a high-power inflator when the airbelt is inflated, and an airbelt apparatus employing this airbelt.
Solution to Problem
[0010] An airbelt according to a first aspect includes a folded body formed by folding a bag-like belt into a belt-like shape, the bag-like belt being to be inflated by introducing gas from one end thereof in the longitudinal direction, and a cover covering the folded body of the bag-like belt, wherein the folded body and the cover are sewn together with a plurality of tear seams, and wherein the plurality of tear seams extend in the width direction of the airbelt and are spaced in the longitudinal direction of the airbelt.
[0011] An airbelt according to a second aspect is the airbelt according to the first aspect, wherein part of each tear seam extending in the width direction is located closer to the one end of the airbelt than the other parts of each tear seam.
[0012] An airbelt according to a third aspect is the airbelt according to the second aspect, wherein each tear seam extends while curving or bending such that the middle part thereof in the width direction of the airbelt is located on the side of the one end of the airbelt.
[0013] An airbelt according to a fourth aspect is the airbelt according to the third aspect, wherein the distance L between the middle part and the terminal part of each tear seam in the longitudinal direction of the airbelt is from 1 mm to 20 mm.
[0014] An airbelt according to a fifth aspect is the airbelt according to the second aspect, wherein each tear seam extends obliquely to the width direction of the airbelt.
[0015] An airbelt according to a sixth aspect is the airbelt according to the second aspect, wherein each tear seam extends in a zigzag manner such that a plurality of parts thereof in the width direction of the airbelt are located closer to the one end than the other parts.
[0016] An airbelt according to a seventh aspect is the airbelt according to any one of the first to sixth aspects, wherein the width W 1 of the tear seams is from 20% to 100% of the width W 0 of the airbelt.
[0017] An airbelt apparatus according to an eighth aspect includes an inflatable airbelt, and an inflator that supplies gas into the airbelt and thereby inflates the airbelt, wherein the airbelt is that according to any one of the first to seventh aspects.
Advantageous Effects of Invention
[0018] In the airbelt of the present invention, a folded body of a bag-like belt and a cover covering this are sewn together with tear seams, and therefore the displacement of the cover relative to the folded body of the bag-like belt is prevented. In the present invention, the tear seams are spaced in the longitudinal direction of the airbelt, and therefore the tear seams can be torn without the need to use a high-power inflator when the airbelt is inflated.
[0019] When part of each tear seam is located closer to one end of the airbelt (more upstream in the gas flow direction) than the other parts, the stress concentrates to the part of each tear seam, and the tear of each tear seam starts in this part. Once the tear starts, the tear spreads throughout each tear seam, and the whole of each tear seam tears in a short time.
[0020] When the airbelt extends so as to curve such that the middle part of each tear seam in the width direction of the airbelt is located on the side of the one end, the shear stress produced in each tear seam when the cover and the folded body of the bag-like belt try to be displaced from each other is distributed throughout each tear seam, and the concentration of shear stress in part of each tear seam is prevented.
[0021] When the distance L between the middle part and the terminal part of each tear seam is 1 mm or more, more specifically 4 mm or more, such an advantageous effect can be sufficiently obtained.
[0022] The percentage (W 1 /W 0 )×100% of the width W 1 of the tear seams to the width W 0 of the airbelt is preferably from about 20% to about 100%, more preferably from about 30% to about 50%.
BRIEF DESCRIPTION OF DRAWINGS
[0023] FIG. 1 is a perspective view of the inside of an automobile having an airbelt apparatus according to an embodiment.
[0024] FIG. 2 is a perspective view of the airbelt apparatus according to the embodiment with the airbelt inflated.
[0025] FIG. 3 is an exploded perspective view of an airbelt according to the embodiment.
[0026] FIG. 4 a is a front view of the airbelt apparatus according to the embodiment during manufacture, FIG. 4 b is a sectional view taken along line B-B of FIG. 4 a , and FIG. 4 c is a sectional view taken along line C-C of FIG. 4 b.
[0027] FIG. 5 a is a front view of the airbelt apparatus according to the embodiment during manufacture, and FIG. 5 b is a front view of the airbelt that has been manufactured.
[0028] FIG. 6 is a sectional view taken along line VI-VI of FIG. 5 b.
[0029] FIG. 7 is a front view of part of the airbelt according to the embodiment.
[0030] FIG. 8 is a perspective view of a tongue part of the airbelt.
[0031] FIG. 9 is a front view of part of an airbelt according to another embodiment.
[0032] FIG. 10 is a front view of part of an airbelt according to still another embodiment.
[0033] FIG. 11 is a front view of part of an airbelt according to a different embodiment.
DESCRIPTION OF EMBODIMENTS
[0034] A first embodiment of the present invention will now be described with reference to FIG. 1 to FIG. 8 .
[0035] First, with reference to FIG. 1 and FIG. 2 , the overall configuration of a seat having an airbelt apparatus will be described schematically. FIG. 1 is a perspective view showing the right-side seat and its vicinity of a two-seat (two-seater) automobile equipped with an airbelt apparatus, FIG. 2 is a perspective view of the airbelt apparatus with the airbelt inflated, and FIG. 8 is a perspective view of a tongue of this airbelt.
[0036] This seat 1 has a seat cushion 2 , a seat back 3 , and a headrest 4 . This headrest 4 is provided with a slit 5 for passing an airbelt 10 . The slit 5 has such a shape that it extends downward from the upper end of the right side of the seat back 3 . When an occupant is not sitting in the seat 1 , the airbelt 10 hangs from this slit 5 along the right side of the front of the seat back 3 .
[0037] In this embodiment, a retractor 15 for retracting a webbing 14 connected to the airbelt 10 is disposed behind the seat 1 . The webbing 14 reaches the retractor 15 through an opening 7 provided in the vehicle body interior panel 6 . The retractor 15 is fixed to the vehicle body member.
[0038] In this embodiment, a retractor 16 for retracting a lap belt 11 is disposed under the seat cushion 2 , and is fixed to the seat frame. The lap belt 11 is passed through an opening (not shown) provided in the seat cushion 2 .
[0039] The retractors 15 and 16 are both emergency lock retractors (ELRs).
[0040] Since the airbelt 10 hangs along the front of the seat back 3 , when the occupant opens the door and sits in the seat 1 or leaves the seat 1 , the back of the occupant slides on the airbelt 10 , and a folded body of a bag-like belt and a cover in the airbelt 10 try to be displaced from each other. In this embodiment, the folded body of the bag-like belt and the cover 2 of the airbelt 10 are sewn together with tear seams, and thereby this displacement is prevented.
[0041] As shown in FIG. 2 , the airbelt apparatus has an airbelt 10 forming a shoulder belt portion that goes over one of the shoulders (the right shoulder in this case) of an occupant sitting in the seat 1 and goes over the front of the upper half of the body of the occupant diagonally (from top right to bottom left in this embodiment), a webbing 14 connected to the upper end of the airbelt 10 , a lap belt portion 11 that goes over the waist of the occupant in the horizontal direction, a buckle device 12 installed adjacent to one side (the left side in this embodiment) of the seat, a tongue 13 that is inserted into and engaged with the buckle device 12 when the belt is used, a retractor 15 that retracts the webbing 14 , and a retractor 16 that retracts the lap belt portion 11 .
[0042] The buckle device 12 is provided with an inflator 17 , and gas jetted from the inflator 17 is introduced into the airbelt 10 .
[0043] As shown in FIG. 8 , the tongue 13 is provided with a tongue plate 13 a that is inserted into the buckle device 12 , and a nozzle 13 b for receiving gas from the inflator 17 and guiding the gas into the airbelt 10 .
[0044] To the distal end of the lap belt portion 11 , an anchor plate 11 a is attached. The anchor plate 11 a is fixed to the tongue 13 with a bolt. Reference sign 11 b denotes a decorative cap for concealing the head of this bolt.
[0045] With reference to FIG. 3 to FIG. 7 , the configuration of the airbelt 10 will be described in detail.
[0046] As shown in FIG. 3 , the airbelt 10 includes a bag-like belt 21 , a strap 22 extending from the rear end of the bag-like belt 21 , a mesh webbing 23 covering the bag-like belt 21 , a mesh cover 25 covering the mesh webbing 23 , and a heat-resistant cloth 26 disposed in the bag-like belt 21 .
[0047] The bag-like belt 21 is inflated by gas from the inflator 17 , and is folded into an elongate rectangular belt-like shape as shown in FIG. 3 . In this embodiment, as shown in FIG. 2 , the rear end of the bag-like belt 21 is significantly inflated on the right side of the occupant's head and restrains the head from the right.
[0048] The strap 22 is made of a belt-like cloth and is sewn to the rear end of the bag-like belt 21 . The strap 22 may be formed integrally with the base cloth of the bag-like belt 21 .
[0049] The mesh webbing 23 is an elongate tubular envelope-shaped member that opens at both ends. As shown in FIG. 4 a and FIG. 4 b , the strap 22 , the distal end of the webbing 14 , and the rear end of the mesh webbing 23 are stacked and sewn together using a sewing machine. Reference sign 30 denotes these seams. When the webbing 14 is sewn to the strap 22 , the webbing 14 is not connected to the retractor 15 .
[0050] In this embodiment, as shown in FIG. 4 c , the strap 22 is folded in two along its longitudinal fold line, and the webbing 14 is sandwiched between the two halves of the strap 22 . However, the strap 22 may be a flat sheet that is not folded in two. The rear end of the mesh webbing 23 is almost coincident with the rear end of the bag-like belt 22 .
[0051] The full length of the mesh webbing 23 is slightly longer than the folded bag-like belt 21 , and the distal end of the mesh webbing 23 extends from the distal end of the bag-like belt 21 . As shown in FIG. 3 , a narrow neck portion 23 a is provided near the distal end of the mesh webbing 23 , and the part 23 b on the distal end side of the neck portion 23 a is slightly narrower than the main body part of the mesh webbing 23 . In the vicinity of the neck portion 23 , an oblique side 23 c intersecting obliquely with the longitudinal side of the mesh webbing 23 is formed. The mesh webbing 23 opens at the oblique side 23 c and thereby an opening is formed. As shown in FIG. 4 a , the distal end 21 a of the bag-like belt 21 extends through the opening at the oblique side 23 c toward the outside of the mesh webbing 23 and is connected to the nozzle 13 b of the tongue 13 .
[0052] Into the distal end of the bag-like belt 21 , the heat-resistant cloth 26 is inserted. The distal end 26 a of the heat-resistant cloth 26 and the distal end 21 a of the bag-like belt 21 are fitted onto the rear end of the nozzle 13 b and are fixed to the nozzle 13 b with a securing ring 13 d . The nozzle 13 b is fixed to a holder portion 13 c integral with the tongue plate 13 a by bolting or the like.
[0053] At the rear end of the tongue plate 13 a , an elongate rectangular opening 13 e is provided. As shown in FIG. 4 a , the distal end portion 23 b of the mesh webbing 23 is inserted into the opening 13 e and is folded back in the neck portion 23 a , and the distal end portion 23 b is placed on the main body of the mesh webbing 23 . Then, the protruding portion 21 b of the bag-like belt 21 ( FIG. 3 ), the main body portion of the mesh webbing 23 , and the distal end portion 23 b of the mesh webbing 23 are sewn together using a sewing machine. Reference sign 27 in FIG. 4 a denotes this seam.
[0054] In this manner, the distal end of the mesh webbing 23 is connected to the tongue plate 13 a . As described above, the rear end of the mesh webbing 23 is sewn to the webbing 14 with seams 30 . The mesh webbing 23 is heat-stretched so as not to stretch in the longitudinal direction. For this reason, when a tensile force is applied to the airbelt 10 , the tensile load between the webbing 14 and the tongue plate 13 a is borne by the mesh webbing 23 .
[0055] The mesh webbing 23 is made of woven fabric, and stretches flexibly in the diameter increasing direction when the bag-like belt 21 is inflated. However, as described above, the mesh webbing 23 is heat-stretched so as not to stretch in the longitudinal direction. For this reason, when the airbelt 10 is inflated, the increase in diameter of the mesh webbing 23 decreases the length of the mesh webbing 23 . Thereby, pre-tension is applied to the airbelt 10 and the webbing 14 .
[0056] As shown in FIGS. 5 and 6 , the mesh cover 25 is attached so as to cover the mesh webbing 23 . The mesh cover 25 is a flat tubular envelope-shaped member that opens at both ends. The mesh cover 25 is sewn into a tubular shape, and the sewn portion of the mesh cover 25 in the longitudinal direction corresponding to the occupant side is a tear seam 25 t ( FIG. 1 ) that tears when the bag 10 is inflated.
[0057] The rear end of the mesh cover 25 is caused to protrude slightly from the rear ends of the mesh webbing 23 and the strap 22 , and this protruding portion is sewn to the webbing 14 with a seam 32 .
[0058] The thread forming the seams 30 and 32 is sufficiently strong, and does not break when the bag-like belt 21 is inflated.
[0059] A plurality of parts, in the longitudinal direction, of the integral belt-like airbelt 10 configured as above and including the bag-like belt 21 , the mesh webbing 23 , and the mesh cover 25 are sewn with tear seam 33 . The tear seams 33 , penetrating the airbelt 10 from one surface to the other surface, sew the bag-like belt 21 , the mesh webbing 23 , and the mesh cover 25 together.
[0060] As shown in FIG. 7 , in this embodiment, each tear seam 33 extends in the width direction of the airbelt 10 . Each tear seam 33 curves such that the middle thereof in the width direction of the airbelt 10 is convex toward the upstream side in the gas flow direction, that is to say, toward the tongue 13 . Although both ends of each tear seam 33 are away from the side edges of the airbelt 10 , they may reach the side edges. As shown in the figure, each tear seam 33 has backstitch portions for preventing raveling.
[0061] The distance L in the longitudinal direction of the airbelt between the middle part of each tear seam 33 and the terminal part of each tear seam 33 is preferably from about 1 mm to about 20 mm, more preferably from about 4 mm to about 20 mm. The length W 1 of each tear seam 33 in the width direction of the airbelt is preferably from about 20% to about 100%, more preferably from about 30% to about 50% of the width W 0 of the airbelt 10 .
[0062] Within this range, the slip between the bag-like belt 21 , the mesh webbing 23 , and the mesh cover 25 can be sufficiently prevented.
[0063] The distance L in the longitudinal direction of the airbelt between the middle part and both ends of each tear seam 33 is preferably from about 2% to about 60%, more preferably from about 8% to about 60% of the width W 1 of each tear seam 33 . Since each tear seam 33 is curved such that the middle part of each tear seam 33 is located on the tongue 13 side, the stress concentrates to the middle part of each tear seam 33 when the airbelt 10 is inflated, and the middle part of each tear seam 33 tears first. That is to say, since gas flows in from the tongue 13 side, the stress concentrates to the middle part of each tear seam 33 closest to the tongue 13 . The middle part of the airbelt 10 in the width direction inflates most easily. Also because of this, the stress concentrates to the middle part of each tear seam 33 . Once the middle part of each tear seam 33 tears, the tear of each tear seam 33 propagates rapidly to both sides, the whole of each tear seam 33 tears rapidly, and the airbelt 10 is inflated.
[0064] The distance between the tear seams 33 is preferably from about 50 mm to about 200 mm, more preferably from about 80 mm to about 120 mm. The number of the tear seams 33 is preferably from about 1 to about 18, more preferably from about 3 to about 10. The intervals between the tear seams 33 may be equal or unequal.
[0065] The above-described mesh cover 25 has such a length that the distal end thereof covers the rear end of the tongue plate 13 a.
[0066] Case halves 13 A and 13 B for the tongue are attached so as to cover the rear part of the tongue plate 13 a and the distal end of the mesh cover 25 . The case halves 13 A and 13 B are made of synthetic resin. By positioning the case halves 13 A and 13 B face to face and one on top of the other, the rear part of the tongue plate 13 a and the distal end of the mesh cover 25 are encapsulated. After that, the rear end of the webbing 14 is connected to the retracting shaft of the retractor 15 .
[0067] In the airbelt and airbelt apparatus configured as above, the airbelt 10 is provided with tear seams 33 , and the displacement of the bag-like belt 21 , the mesh webbing 23 , and the mesh cover 25 on the superimposed surfaces is prevented. When the airbelt 10 is inflated, each tear seam 33 tears rapidly. In this embodiment, each tear seam 33 curves gently, and there is no angular part. Therefore, when the superimposed surfaces try to be displaced, the stress applied to each tear seam 33 is distributed throughout each tear seam 33 .
[0068] In the above-described embodiment, each tear seam 33 curves gently. Alternatively, tear seams 34 bent in a dogleg-shape as shown in FIG. 9 may be provided. Like the W-shaped tear seam 35 shown in FIG. 10 , a plurality of parts of each tear seam may be located on the tongue side. As shown in FIG. 11 , linear tear seams 36 intersecting obliquely with the width direction of the airbelt 10 may be provided.
[0069] Although a particular aspect of the present invention has been described in detail, it will be obvious to those skilled in the art that various changes may be made without departing from the intent and scope of the present invention.
[0070] This application is based on Japanese Patent Application No. 2009-217282 filed Sep. 18, 2009, which is incorporated by reference in its entirety. | An airbelt wherein a folded body of a bag-like belt is covered with a cover, and the two are sewn together with tear seams, and wherein the tear seams can be torn without the need to use a high-power inflator when the airbelt is inflated, and an airbelt apparatus employing this airbelt are provided. In one form, a mesh webbing and a mesh cover cover the bag-like belt. A plurality of parts of the airbelt in the longitudinal direction are sewn with the tear seams. The tear seams extend in the width direction of the airbelt and curve so as to be convex toward a tongue. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
A current manufacturing process for decorating wallboard panels such as hardboard or particle board applies conventional printing methods, e.g. gravure or silk screen, to decorate a panel substrate with the selected design, and thereafter, a water-resistant, polymeric coating is applied over the decorated substrate. Generally, there are a limited number of colored substrates to which a large variety of designs or decorations are applied. A massive inventory of colored panel substrates, fully decorated panels and decorating inks or dyes are required at each manufacturing and/or warehousing facility.
For example, if a small amount of product having a particular design is ordered, a minimum economic production run may require that 1000 panels be produced to justify the set up costs. The panels produced in excess of the amount required to fill the order must be inventoried, and in some cases it takes many months to sell the "excess" production. In addition, the introduction of a new line of decorated panels requires substantial inventories. Slow moving products often back-up, and panel designs which are being phased out are often difficult to move. The wallboard panel industry needs a low cost manufacturing process which will eliminate product ovrruns and substantially reduce the inventory levels. 2. Description of the Prior Art
The decoration of textile fabrics with sublimable inks or dyes has undergone rapid development during the past ten years. The process is commonly referred to as heat transfer printing wherein a decoration or design is printed on a paper transfer sheet with a subliming dye or ink, and thereafter, the paper is pressed against the textile fabric and heated for a brief period of time whereby the ink is vaporized and transferred to the textile fabric. The dye penetrates into the fabric, forming the design or decoration which was printed on the transfer sheet. This process of heat transfer printing is particularly applicable to knitted polyester fabrics which are very receptive to many subliming dyes. U.S. Pat. No. 3,363,557 illustrates a process for the heat transfer of coloring agents from a transfer sheet to a fabric or other material such as wood, paper, other cellulosic materials, plastic surfaces and even metallic surfaces. This patent does not disclose using the heat transfer printing process to decorate a water-resistant, rigid panel having a clear polymeric coating on one surface.
More recently, U.S. Pat. No. 3,860,388 discloses a method for heat transfer printing with a sublimable dye through a polyolefin release layer to decorate a non-porous thermoplastic sheet or material coated with or bonded to a thermoplastic dye receptor. The method of this patent employs a polyolefin sheet between the dye transfer sheet containing dispersed dyes and the dye receptor thermoplastic material to prevent the printed transfer sheet (paper) from sticking to the thermoplastic dye receptor material. The temperatures employed to sublime or heat transfer the dye are generally sufficient to soften the polyolefin sheet, but it does not stick to the thermoplastic dye receptor material. The method can be used to obtain either high clarity dye transfer, or dye transfer and concurrently lamination of the thermoplastic dye receptor material to a substrate such as hardboard or fiberboard. It appears that in all cases employing a hardboard or fiberboard laminate base material, the dye receptor surface was laminated to the hardboard concurrently with the dye transfer process, and a cured, pre-coated rigid panel was not decorated.
U.S. Pat. No. 3,922,445 discloses a heat transfer printing sheet which can be used to transfer print a variety of base materials. Included in the listed base materials are films and sheets or various synthetic resins, hardboard and gypsum board. There is no disclosure in this patent that a cured, pre-coated rigid panel having a clear, water-resistant polymeric coating can be heat transfer printed.
U.S. Pat. No. 3,952,131, issued on Apr. 20, 1976, discloses a heat transfer print sheet having a polyolefin coating overlying the printed surface to prevent the heat transfer print sheet from adhering to a substrate to which the printing is transferred. The method includes consolidating a plurality of layers of material with heat and pressure, and concurrently therewith, a sublimable dye is transferred from the print sheet to a substrate material. FIG. 3 discloses a finished laminate comprising a polyester film printed with a sublimable dye and laminated to a metalized layer, phenolic impregnated kraft paper and hardboard. There is no disclosure that a cured, precoated rigid panel can be heat transfer printed without requiring a polyolefin layer adjacent to the heat transfer print sheet to prevent adherence to the printed substrate.
There was a series of articles in the American Dyestuff Reporter, February 1975, pp. 23-35, 41, 43-50 and 52-56 disclosing the development of heat transfer printing in the textile fabric industry. Many sublimable dyes are disclosed in these articles and their effectiveness in printing various types of fabric. There is no disclosure that heat transfer printing can be used to decorate a cured, pre-coated rigid panel having a clear, water-resistant polymeric coating on one surface.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a method for making a decorated, water-resistant, rigid panel which solves the problem of maintaining large inventories of decorated panels. Another object is to provide a method for decorating a cured, precoated hardboard panel by heat transferring a sublimable ink decoration from a print sheet to the pre-coated hardboard panel. A further object of the invention is to provide a decorated, water-resistant, rigid panel having a clear polymeric coating on one surface which is impregnated by a sublimable coloring agent, and the decorated surface has a light stability of at least about 40 hours as measured by the Standard Carbon-Arc Fadometer test (ASTM G25-70), Continous Exposure to Light, Method A. A still further object is to provide a decorated, water-resistant wallboard panel for use in shower stalls, kitchens and similar applications in which water-resistance and the decorative surface are important factors in customer acceptance.
It has been discovered that a decorated, water-resistant, rigid panel can be manufactured by bringing a cured, pre-coated rigid panel into contact with a printed sheet having a decoration formed by a sublimable coloring agent and transferring the coloring agent into the coating on the rigid panel by means of heat and pressure. In this manner, the decorated, water-resistant panel is made from a cured, pre-coated rigid panel at the time and in the quantities required by the purchaser or user. The rigid panel forming the substrate base may be a cellulosic formed board such as hardboard, particle board, softboard, insulation board, or it may be a coated gypsum panel or a coated plywood panel.
One of the important factors in practicing the method of this invention is the polymeric coating applied to the surface of the rigid panel and cured by heat, ultra-violet radiation or other curing means, prior to contacting the panel surface with the printed transfer sheet containing the sublimable coloring agent. The polymeric coating provides both water-resistance and a receptor surface for retaining the coloring agent. It is preferred that the surface coating be a clear, polymeric coating selected from alkyd-melamine resins, polyester resins, alkyd resins and acrylic polymers. Any water-resistant, clear polymeric coating material generally used to render hard cellulosic panels water-resistant can be used in this invention, provided that the cured polymer is permeable to the subliming coloring agent and will function as a receptor surface for said coloring agent. It is preferred that the clear polymeric coating comprise a layer having a thickness of at least about 1 mil.
In addition to the water resistant, clear polymeric top coating, the rigid panel may also have one or more substrate coatings. These substrate coatings may also comprise polymeric coatings, however, they may contain pigments, coloring agents or other fillers, whereas it is essential that the top coat be clear so as not to interfere with the permeability and deposition of the sublimable coloring agent.
The sublimable coloring agents (ink or dye) used in this invention are well known in the textile decorating art and do not constitute a critical feature. The coloring agents may comprise a resin binder and a dyestuff which is generally referred to as a disperse dye. It is generally preferred that the disperse dye be an organic dyestuff such as disazo dyes, anthraquinone dyes and methine dyestuffs. The sublimable coloring agent is printed on a transfer sheet of paper or other material, which may contain a special release coating, and it must be capable of being heat transferred into the clear polymeric coating at the sublimation temperature of the dye. Generally, the sublimable coloring agent should be capable of being heat transferred or sublimed at temperatures ranging from about 150° C. to about 220° C.
In general, the method of this invention comprises supplying a cured, pre-coated rigid panel having a clear, water-resistant polymeric coating on one surface of the panel and a printed sheet having a design, picture or other form of decoration on one surface, said decoration being formed by a sublimable coloring agent. The rigid panel and the printed sheet are originally maintained at room or ambient temperature. The coated surface of the rigid panel and the decorated surface of the printed sheet are brought into physical contact, and their surfaces are maintained in contact for a brief period of time by applying light pressure to the surfaces. In general, pressures ranging from about 1 to about 10 psi are sufficient to maintain intimate contact between the surfaces, however, greater pressures up to 50 psi may be used. The sublimable coloring agent is rapidly transferred from the printed sheet into the clear polymeric coating on the rigid panel, and the heat and pressure are applied to the surfaces for only a short period of time, ranging from about 10 seconds to about 3 minutes. In most cases, the heat transfer process can be completed in less than one minute.
One of the features of this invention is the use of a rigid panel having a cured, clear polymeric coating which functions as the receptor surface for the sublimable coloring agent. Since the coating is cured to a hard, thermoset polymeric material, the problem of the printed sheet sticking to the rigid panel is obviated, particularly when the method is carried out using low pressure and a rapid (30 seconds or less) heat transfer. It is preferred that the pre-coated rigid panel have at least one substrate coating under the cured, clear polymeric top (surface) coat. The substrate coating may comprise a resin binder and a pigment or other coloring agent to provide a uniform background color for the sublimable coloring agent decoration. Additional substrate coatings may be used to improve the adhesion of the background color coat or the clear polymeric top coat to the rigid panel material.
The decorated, water-resistant, rigid panels made in accordance with this invention have many uses. The panels may be used as walls for decorated bathtub or shower enclosures wherein wall panels comprise three sides of the enclosure and must be water resistant. These panels also provide a highly decorative surface which enhances the beauty and appearance of the facility. The panels may be used as a splashboard in and around kitchen sinks and counters which require a water-resistant material to prevent stains caused by splashed water and other liquids. Other potential applications for the decorated, water-resistant panels are in places which must have resistance to water or other liquid soilants and those places in which a washable or readily cleaned surface is desired. In addition, the decorative feature of the panels may be emphasized such as a material to be used in making furniture, particularly children's furniture, wall decoration and graphic displays. The reduced costs in manufacturing decorated, water-resistant panels provided by this invention extends the commercial availability of such panels to applications not generally considered to be markets for such materials.
The above and other objects and advantages of this invention will be more fully described in the description of the preferred embodiment, particularly when read in conjunction with the accompanying drawings which form a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing of a heat transfer press for making individual decorated, water-resistant, rigid panels in accordance with this invention.
FIG. 2 is a schematic drawing of a heat transfer printing press for continuously making decorated, water-resistant, rigid panels in accordance with this invention.
FIG. 3 is a schematic drawing of an alternative heat transfer printing press for continuously making decorated, water-resistant, rigid panels in accordance with this invention.
DESCRIPTION OF PREFERRED EMBODIMENT
The method of this invention comprises making a decorated, water-resistant, rigid panel by employing a heat transfer process and a sublimable coloring agent to decorate a cured, pre-coated rigid panel having a clear, water-resistant polymeric coating on one surface of the panel. It is essential that the panel coating be completely cured to a hard, thermoset-like material prior to decorating it by the heat transfer process in order to prevent the sheet printed with the sublimable coloring agent from sticking to the rigid panel after contact therewith under heat and pressure. Another important factor is that the top (surface) coating on the rigid panel must be clear and a good receptor for the sublimable ink, for it has been found that the use of pigments or coloring matter in the top coating interferes with the receptivity of the coating for the sublimable coloring agent.
The heat transfer process can be carried out quickly, efficiently and cleanly. Light pressure ranging from about 1 to 50 psi is used to maintain physical contact between the pre-coated rigid panel and the printed sheet carrying the decoration or print. The heat transfer process is generally carried out at temperatures ranging from about 150° C. to about 220° C. and the heat and pressure are applied to the panel and printed sheet surfaces for a very short period of time, ranging from about 10 seconds to about 3 minutes. After removing the pressure and the heat source, the printed sheet is readily removed from the panel surface, and the printed sheet may be reused if it retains sufficient sublimable coloring agent for decorating additional panels.
Referring now to the drawings, FIG. 1 illustrates a heat transfer press (10) for making individual decorated, water-resistant, rigid panels in accordance with this invention. The heat transfer press (10) comprises a base member (11) covered with a resilient silicone rubber plate (12) which serves as a support member for the rigid panel which is to be decorated. Located above the base member (11) and silicone plate (12), there is a moveable member (13) comprising an adjustable hot platten (14) attached to a fiberglass insulated heat shield (15) to which there is attached an activator handle (16). There is an attachment means (17) which connects the member (13) to a control panel (18) portion of the heat transfer press (10) in such a manner that the moveable member (13) can be brought into contact with the silicone plate (12). The attachment means (17) also functions as a duct for the electrical resistance element used to heat the hot platten (14) and also for an air pressure line used to provide the pressure exerted by the moveable member (13) in compressing the printed sheet (19) against the rigid panel (20). The air is supplied to the heat transfer press through the air receptacle (21). The control panel (18) contains the instruments for controlling the pressure and the duration of the process including an ON/OFF indicator lamp (22), an air pressure control knob (23), an air pressure gauge (24), a heat element ON/OFF indicator lamp (25) and an automatic reset timer (26). A heat control knob and a thermometer showing the temperature of the hot platten (14) are not illustrated, but they are located on the top surface of the heat shield (15).
The heat transfer press illustrated in FIG. 1 is limited to decorating one rigid panel in each batch, which may be feasible for producing small quantities of decorated panels. However, for the mass production of large quantities of decorated panels, a continuous process is required. Apparatus for practicing the method of this invention in a continuous process is illustrated in FIG. 2.
A heat transfer printing press (30) for carrying out a continuous process comprises a rubber conveyor belt (31) which may be coated with polytetrafluorethylene to enable the belt to withstand the elevated temperatures used in the heat transfer process. The belt (31) may have a variable width and length, depending upon the size of the rigid panel to be decorated. The conveyor belt (31) is driven at adjustable speeds by two motor driven, hard rubber rollers (32) and (33) which may be placed about 4 feet apart, with two intermediate, non-driven, hard rubber rollers (34) and (35) placed opposite rollers (36) and (37) to compress the rigid panel (40) and printing paper (41). Each of these rollers may be about 8 inches in diameter. The two pneumatically operated rollers (36) and (37), each having a silicone rubber coating (38) and (39) respectively, are placed about 2.5 feet apart and are located directly above rollers (34) and (35). The rigid panel (40) is fed to the belt (31) with the transfer printing paper (41) containing the sublimable coloring agent fed from a roller to the surface of the rigid panel (40). The rollers (36) and (37) are capable of being lowered into contact with the conveyor belt (31) whereby the rigid panel (40) and printing paper (41) are compressed as they pass between the rollers (34) and (36) and rollers (35) and (37) by a pressure up to about 50 psi. Radiant heaters (42) and (43) are adjacent to the silicone rubber coated rollers (36) and (37) and are used to heat these rollers to temperatures ranging from about 150° C. to about 220° C. Hot roller (36) is lowered pnuematically to apply heat and pressure to the printing paper (41) and the rigid panel (40). As the paper and panel pass through the first set of rollers, another radiant heater (44) provides heat to the paper and panel whereby the sublimation of the coloring agent continues as the paper and panel advance to the second set of rollers. The heat and pressure applied by hot roller (36) causes the transfer paper (41) to adhere to the rigid panel (40) as it comes out of the first set of rollers (34) and (36), whereby the panel (40) and the paper (41) remain in physical contact until the sublimation and printing process is completed. The duration of the heat transfer process is controlled by the speed of the conveyor belt (31). Of course the length of the conveyor belt (31) and the number of sets of rollers are matters of operator's choice and depend upon the size of the rigid panels.
Referring now to FIG. 3, alternative apparatus for practicing the method of this invention in a continuous process is illustrated. The apparatus (50) generally comprises a conveyor system wherein a series of plattens are arranged to provide for the application of heat and pressure to transfer printing paper in physical contact with a rigid panel which is to be decorated. The panel may be 4 feet by 8 feet in size, and therefore, the apparatus is quite large.
One conveyor velt (51) carries several hot plattens (52) which are sectionalized to permit them to travel readily around the motor driven support rollers (53) and (54). The hot plattens (52) function as a heat sink and must have sufficient mass to carry heat from one end of the conveyor to the other. It is preferred that the plattens (52) be made of aluminum, but the load carried by the conveyor belt (51) is still very heavy, and an additional non-driven roller (55) may be required to support the load carried by the belt (51). A radiant heat source (56), such as infra-red lamps, may be used to heat the plattens (52).
Another conveyor belt (57) is supported by motor driven support rollers (58) and (59) which are synchronized with rollers (53) and (54). Trays (60), which are also sectionalized to permit them to travel around the rollers (58) and (59), are adapted to receive and support the rigid panel (61) which is to be decorated. The trays (60) may be made from a plastic material or a light metal such as aluminum. It may also be necessary to have one or more additional support rollers for the conveyor belt (57) and also the conveyor belt (51). Either the plattens (52) or the trays (60), or both, should have a resilient coating, e.g. silicone rubber, to accomodate surface irregularities in the rigid panel and to permit compression of the panel and the transfer printing paper (62) without tearing or otherwise damaging the paper.
A roll (63) of the transfer printing paper is supplied, and the paper (62) passes around the roller (64) and into contact with the panel (61) as it is placed on a tray (60). A conveyor belt (65) and roller (66) system may be used to support the rigid panel before it is placed on the tray (60). The transfer printing paper (62) passes between the hot plattens (52) and the panels supported on the trays (60) and is compressed against the panel while the heat transer process is being carried out. The plattens (52) are aligned with the trays (60) and both are firmly fastened to the conveyor belts (51) and (57) respectively. After the heat transfer printing process is completed, the decorated panel (67) is discharged from the tray (60), and the transfer printing paper (62) passes over roller (68) and onto a take-up roll (69).
One of the objects of this invention is to provide a decorated, waer-resistant, rigid panel having a clear polymeric coating on one surface which has a light stability of at least about 40 hours as measured by the Standard Carbon-Arc Fadometer test (ASTM G25-70), Continuous Exposure to Light, Method A. This test procedure is fully described in the Annual Book of ASTM Standards, Part 41, pages 789-793. It has been found that the method of this invention does consistently provide a decorated, water-resistant, rigid panel having a light fastness rating of at least 40 hours, and in many cases, the panels have a light fastness rating of more than 100 hours.
The following working examples illustrate the method for making a decorated, water-resistant, rigid panel in accordance with this invention:
EXAMPLE 1
In carrying out this example, a heat transfer press (Hix N-600 commercially available from Hix Automation, Inc.) similar to the press illustrated in FIG. 1 was used to decorate a cured, pre-coated hardboard panel. The hardboard panel had a solid white ground coat containing an alkyd resin binder, and it had a clear top coat consisting of an alkyd-melamine resin. The top coat had a thickness of about 1.5 mils. A printed transfer paper containing a sublimable blue dye (Celliton BLue G - Colour Index 64500) in a decorative design was used to supply the sublimable coloring agent.
The pre-coated hardboard panel was placed in the heat transfer press and the printed side of the transfer paper was placed against the alkyd-melamine resin coated surface of the panel. The press was closed and a polytetrafluoroethylene coated hot platten, heated to a temperature of about 160° C., was brought into contact with the printed transfer paper and pressed it against the hardboard panel. A pressure of about 40 psi was used to compress the paper and the panel. The heat and pressure were applied for about 60 seconds during which time the blue dye was sublimed, transferred from the printing paper and penetrated the clear top coat on the hardboard panel. The transfer paper was stripped from the panel, and the blue dye decoration in the clear top coat provided a decorated, water-resistant, hardboard panel.
EXAMPLE 2
Several sublimable coloring agents were evaluated for their ability to decorate hardboard panels. Coloring agents from different suppliers were tested in carrying out the method of this invention. In some cases, the sublimable coloring agents were supplied as prints on heat transfer paper, and in others, the ink or dye was supplied and it was printed on paper by either silk screening or a gravure method. All of the hardboard panels were cured and pre-coated with a solid white ground coat containing an alkyd resin binder and a clear top coat consisting of an alkyd-melamine resin. The top coat had a thickness of about 1 mil.
As in Example 1, all of the hardboard panels were decorated using a heat transfer press similar to the press illustrated in FIG. 1 to apply heat and pressure to the transfer paper and hardboard panel. The hot platten was heated to a temperature of about 205° c. A transfer pressure of 40 psi was used to compress the transfer paper against the hardboard panel.
Following the manufacture of the decorated, water-resistant, hardboard panels using a variety of subliming inks, each decorated hardboard panel was tested for its light stability in accordance with the Standard Carbon-Arc Fadometer test (ASTM G-25-70) using Method A-Continuous Exposure to Light. The following results were recorded:
______________________________________ Ink Color/ Light Stability DecorationSource Identification Rating Quality______________________________________No. 1 Red 22 hrs. Fair" Black " "" Blue " "" Green " "" Yellow-I 66 hrs. "" Yellow-II 100 hrs. "______________________________________
For Source No. 1, the inks which were supplied were thick and had to be diluted by conventional ink extenders prior to being gravure printed on the transfer paper. The hardboard decoration was not sharp in appearance.
______________________________________ Ink Color/ Light Stability DecorationSource Identification Rating Quality______________________________________No. 2 Red 75 E 2071 60 hrs. Good" Yellow 75 E 2070 60 hrs. "" Red 75 E 2119 40 hrs. "" Blue 75 E 2072 60 hrs. "" Black 75 E 2546 40 hrs. "______________________________________
For Source No. 2, the heat transfer paper was supplied already printed with the sublimable ink. It was determined that the paper did not stick to the hardboard panel after the heat transfer was completed. The decorated hardboard had a good appearance.
______________________________________ Ink Color/ Light Stability DecorationSource Identification Rating Quality______________________________________No. 3 Yellow 6100-32 150 hrs. Good" Red 6100-34 " "" Blue 6100-36 " "" Black 6100-70 " "______________________________________
Source No. 3 supplied disperse dyes which were silk screened onto the heat transfer paper. A very sharp print and high dye strength were achieved with the silk screen method. The decorated hardboard had a good appearance and outstanding light stability.
______________________________________ Ink Color/ Light Stability DecorationSource Identification Rating Quality______________________________________No. 4 Orange 60 hrs. GoodNo. 4 Green 40 hrs. "" Blue 40 hrs. "______________________________________
Source No. 4 supplied a printed heat transfer paper. The decorated hardboard had a sharp image, and the heat transfer peper did not stick to the coated hardboard.
______________________________________ Ink Color/ Light Stability DecorationSource Identification Rating Quality______________________________________No. 5 Kanoe (Maroon 13683) 40 hrs. Good" Dizzy Daisy (Blue, White, 40 hrs. " Red, Green 13753)" Roman Check (Blue 40 hrs. " 13726)" Five Stripe (Blue, Black, 100 hrs. " Yellow 13686)" David's Chevron (Blue, 130 hrs. " Black, Red 13601)______________________________________
Source No. 5 supplied a printed heat transfer paper, each with a fanciful decoration. The paper with David's Chevron print got stuck to the hardboard panel. The panels decorated with Five Stripe and David's Chevron had outstanding light stability. The decorated panels had a good appearance.
______________________________________ Ink Color/ Light Stability DecorationSource Identification Rating Quality______________________________________No. 6 142-1 -- Poor" 142-2 -- "" 142-3 20 hrs. "" 142-4 40 hrs. "" 142-5 20 hrs. "" 142-6 100 hrs. "" 142-7 44 hrs. "" 142-8 60 hrs. "" 142-9 -- "______________________________________
Source No. 6 supplied a printed heat transfer paper. Almost all of the inks stayed on the surface of the panel top coat. It was determined that these printed heat transfer sheets could not be used in practicing the method of this invention.
______________________________________ Ink Color/ Light Stability DecorationSource Identification Rating Quality______________________________________No. 7 Yellow P-343 NT 100 Good" Yellow P-345 NT 100 "" Orange P-368 22 "" Brilliant Red P-314 NT 22 "" Scarlet P-355 22 "" Violet P-344 NT 22 "" Blue P-304 NT 22 "" Blue P-305 NT 22 "" Black XB-6 100 "" Black XB-8 100 "______________________________________
Source No. 7 supplied a printed heat transfer paper. Most of the decorated hardboard panels had a good appearance, and those decorated with the yellow and black inks had outstanding light stability. | A method for making a decorated, water-resistant, rigid panel comprising supplying a cured, pre-coated rigid panel having a clear, water-resistant polymeric coating on one surface of the panel and a printed sheet having a design, picture or other form of decoration on one surface thereof, said decoration being formed by a sublimable coloring agent. The rigid panel and the printed sheet are originally maintained at room or ambient temperature. The coated surface of the rigid panel and the decorated surface of the printed sheet are brought into physical contact, and their surfaces are maintained in contact for a brief period of time by applying light pressure thereto. While the surfaces are maintained in contact, heat is applied thereto for a short period of time to sublime the coloring agent and cause it to be transferred to and penetrate into the polymeric coating on the surface of the rigid panel. The heat is removed from the surfaces, and the printed sheet is separated from the rigid panel whose polymeric coated surface contains the same decoration as appeared on the printed sheet.
The product of this invention comprises a decorated, water-resistant, rigid panel having a clear polymeric coating on one surface, which coating is impregnated by a sublimable coloring agent. The coated surface of the panel comprises at least one clear polymeric top coat and may have additional substrate coatings or layers of polymeric or other materials. It is preferred that the coated surface of the decorated panel have a light stability of at least about 40 hours as measured by the Standard Carbon-Arc Fadometer test (ASTM G25-70), Continuous Exposure to Light, Test Method A. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is continuation of U.S. patent application Ser. No. 13/879,689 filed on Apr. 16, 2013, which is a National Stage entry of and claiming priority to International Application No. PCT/US2012/035754 filed on Apr. 30, 2012.
BACKGROUND
[0002] The present invention relates generally to providing a casing exit for a lateral borehole, and more particularly to systems and methods for providing a casing exit with little or no milling of the casing.
[0003] Hydrocarbons can be produced through relatively complex wellbores traversing a subterranean formation. Some wellbores can include multilateral wellbores and/or sidetrack wellbores. Multilateral wellbores include one or more lateral wellbores extending from a parent (or main) wellbore. A sidetrack wellbore is a wellbore that is diverted from a first general direction to a second general direction. A sidetrack wellbore can include a main wellbore in a first general direction and a secondary wellbore diverted from the main wellbore in a second general direction. A multilateral wellbore can include one or more windows or casing exits to allow corresponding lateral wellbores to be formed. A sidetrack wellbore can also include a window or casing exit to allow the wellbore to be diverted to the second general direction.
[0004] The casing exit for either multilateral or sidetrack wellbores can be formed by positioning a casing joint and a whipstock in a casing string at a desired location in the main wellbore. The whipstock is used to deflect one or more mills laterally (or in an alternative orientation) relative to the casing string. The deflected mill(s) machines away and eventually penetrates part of the casing joint to form the casing exit in the casing string. Drill bits can be subsequently inserted through the casing exit in order to cut the lateral or secondary wellbore.
[0005] Milling the casing exit is a time consuming and potentially harmful process. Milling away the material of the casing creates highly abrasive metallic chips that can cause significant wear on equipment located in the wellbore during the milling process and on equipment that subsequently passes through the area in which the milling takes place. Furthermore, because the mill is only used for milling the casing exit, several trips down the wellbore are required before commencing actual drilling of the associated lateral wellbore.
SUMMARY OF THE INVENTION
[0006] The present invention relates generally to providing a casing exit for a lateral borehole, and more particularly to systems and methods for providing a casing exit with little or no milling of the casing.
[0007] In some embodiments, a method is disclosed. The method may include introducing into a wellbore a casing section having an outer sleeve and an inner sleeve rotatably received within the outer sleeve, the outer sleeve defining an outer window that opens into the wellbore and the inner sleeve defining an inner window rotationally alignable with the outer window, wherein the inner sleeve defines a first alignment portion engageable to rotate the inner sleeve with respect to the outer sleeve, advancing the casing section to a wellbore location with the casing section in a closed configuration where the inner window is rotationally misaligned with the outer window such that the inner sleeve occludes the outer window, securing the casing section at the wellbore location, extending a deflector tool within the casing section such that a second alignment portion provided on the deflector tool engages the first alignment portion, and rotating the deflector tool such that the inner sleeve rotates with respect to the outer sleeve and moves the casing section into an open configuration where the inner window is rotationally aligned with the outer window.
[0008] In other embodiments, a system may be disclosed and may include a cylindrical outer sleeve having a proximal end and a distal end and defining an outer window extending between the proximal and distal ends, a cylindrical inner sleeve rotatably received within the outer sleeve and defining an inner window rotationally alignable with the outer window, the inner sleeve defining a slot engageable to rotate the inner sleeve with respect to the outer sleeve between a first position, where the inner window is rotationally misaligned with the outer window, and a second position, where the inner window is rotationally aligned with the outer window, one or more bearing assemblies configured to prevent axial displacement between the inner and outer sleeves, and a deflector tool extendable at least partially within the inner sleeve and defining a radially protruding lug configured to engage the slot such that the deflector tool is able to rotate the inner sleeve from the first position to the second position.
[0009] The features and advantages of the present invention will be readily apparent to those skilled in the art upon a reading of the description of the preferred embodiments that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The following figures are included to illustrate certain aspects of the present invention, and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art and having the benefit of this disclosure.
[0011] FIG. 1 is a schematic illustration of an offshore oil and gas platform using an exemplary rotatable window casing, according to one or more embodiments disclosed.
[0012] FIG. 2 is a perspective view of the rotatable window casing of FIG. 1 in a closed configuration.
[0013] FIG. 3 is a section view taken along line 3 - 3 of FIG. 2 .
[0014] FIG. 4 is a section view taken along line 4 - 4 of FIG. 2 .
[0015] FIG. 5 is an enlarged perspective view showing an alignment portion of an inner sleeve of the rotatable window casing of FIG. 2 .
[0016] FIG. 6 is a perspective view of the rotatable window casing of FIG. 2 in an open configuration.
[0017] FIG. 7 is a section view taken along line 7 - 7 of FIG. 6 .
[0018] FIG. 8 is an enlarged section view similar to FIG. 3 with the rotatable window casing in the open configuration and showing the alignment portion of FIG. 4 .
[0019] FIG. 9 is a perspective view of a deflector tool configured for use with the offshore oil and gas platform of FIG. 1 and the rotatable window casing of FIG. 2 .
[0020] FIG. 10 is an enlarged perspective view of a portion of the deflector tool of FIG. 9 .
[0021] FIG. 11 is a perspective view showing the rotatable window casing of FIG. 2 in partial section, in the closed configuration, and with the deflector tool of FIG. 5 inserted therein.
[0022] FIG. 12 is a perspective view similar to FIG. 11 where the deflector tool has been rotated and latched into position and the rotatable window casing has been moved from the closed configuration to the open configuration.
[0023] FIG. 13 is a perspective view showing the rotatable window casing of FIG. 2 in the open configuration with the deflector tool of FIG. 9 latched into position.
DETAILED DESCRIPTION
[0024] The present invention relates generally to providing a casing exit for a lateral borehole, and more particularly to systems and methods for providing a casing exit with little or no milling of the casing.
[0025] Referring to FIG. 1 , illustrated is an offshore oil and gas platform 10 that uses an exemplary rotatable window casing section 14 , according to one or more embodiments of the disclosure. Even though FIG. 1 depicts an offshore oil and gas platform 10 , it will be appreciated by those skilled in the art that the exemplary rotatable window casing section 14 , and its alternative embodiments disclosed herein, are equally well suited for use in or on other types of oil and gas rigs, such as land-based oil and gas rigs or any other location. The platform 10 may be a semi-submersible platform 18 centered over a submerged oil and gas formation 22 located below the sea floor 26 . A subsea conduit 30 extends from the deck 34 of the platform 18 to a wellhead installation 38 including one or more blowout preventers 42 . The platform 18 has a hoisting apparatus 46 and a derrick 50 for raising and lowering pipe strings, such as a drill string 54 .
[0026] As depicted, a main wellbore 58 has been drilled through the various earth strata, including the formation 22 . The terms “parent” and “main” wellbore are used herein to designate a wellbore from which another wellbore is drilled. It is to be noted, however, that a parent or main wellbore does not necessarily extend directly to the earth's surface, but could instead be a branch of yet another wellbore. A casing string 52 , including the rotatable window casing section 14 , is at least partially cemented within the main wellbore 58 . The term “casing” is used herein to designate a tubular string used to line a wellbore. Casing may actually be of the type known to those skilled in the art as “liner” and may be made of any material, such as steel or composite material and may be segmented or continuous, such as coiled tubing. The rotatable window casing section 14 forms part of the casing string 52 and is positioned along the casing string 52 at a location where it is desired to create a lateral borehole or wellbore 64 (shown in phantom) that intersects the parent or main wellbore 58 .
[0027] Referring also to FIG. 2 , the casing section 14 includes a generally cylindrical outer sleeve 66 including a proximal end 70 that, in the illustrated embodiment, is configured for coupling to uphole portions of the casing string 52 , and a distal end 74 . The distal end 74 may be coupled to additional downhole portions of the casing string 52 or may include a plug or other wellbore termination depending upon whether the main wellbore 58 continues beyond the casing section 14 or terminates substantially at the casing section 14 . The outer sleeve 66 may be formed by a generally cylindrical outer sleeve wall 78 . The outer sleeve wall 78 may be formed of steel, aluminum, composites, combinations thereof, or substantially any other suitable material or combination of materials. Once the casing section 14 is properly located within the main wellbore 58 , the outer sleeve wall 78 remains substantially fixed with respect to the main wellbore 58 . The outer sleeve wall 78 includes a pre-formed opening that defines an outer window 82 . By “pre-formed” it is meant that the opening that defines the outer window 82 is formed in the outer sleeve wall 78 before the casing section 14 is introduced into the wellbore. In the illustrated embodiment, the outer window 82 is substantially rectangular and arcuate and extends generally from the proximal end 70 to the distal end 74 of the casing section 14 .
[0028] Referring also to FIG. 3 , the casing section 14 also includes a generally cylindrical inner sleeve 86 that is moveably received within the outer sleeve 66 . In the exemplary embodiment of the drawings, the inner sleeve 86 is rotatable with respect to the outer sleeve 66 . The inner sleeve 86 of the exemplary embodiment is closely received by and is in substantial mating engagement with an inner surface 90 of the outer sleeve wall 78 . The inner sleeve 86 includes a proximal end 94 and a distal end 98 that are each rotatably coupled to the outer sleeve 66 by suitable seal and bearing assemblies 102 . In the illustrated embodiment the bearing assemblies 102 permit rotational movement of the inner sleeve 86 with respect to the outer sleeve 66 while substantially preventing or limiting axial movement of the inner sleeve 86 with respect to the outer sleeve 66 . In other embodiments, the inner sleeve 86 may also or alternatively be axially moveable with respect to the outer sleeve 66 .
[0029] The inner sleeve 86 includes an inner sleeve wall 106 . The inner sleeve wall 106 includes a pre-formed opening that defines an inner window 110 . In the illustrated embodiment the inner window 110 includes a proximal portion 114 that is substantially rectangular and arcuate, and a tapered distal portion 118 having a substantially triangular or truncated triangular profile. It should be understood that the section view of FIG. 3 only shows substantially one-half of the inner window 110 . FIG. 3 illustrates the casing section 14 in a first or closed configuration, where the inner window 110 does not communicate with or is otherwise not exposed to the outer window 82 ( FIG. 2 ).
[0030] For instance, as further shown in FIG. 4 , when the casing section 14 is in the closed configuration, the inner sleeve 86 is in a first position in which the inner window 110 is misaligned with the outer window 82 of the outer sleeve 66 . In the illustrated embodiment, when the inner sleeve 86 is in the first position the inner window 110 is substantially diametrically opposed to the outer window 82 . With the casing section 14 in the closed configuration, the inner sleeve 86 , and more specifically the inner sleeve wall 106 , underlies and substantially closes the outer window 82 . Because the outer window 82 is closed by the inner sleeve wall 106 , material and debris located outside of the casing section 14 is generally unable to pass into the interior of the casing section 14 , and vice-versa.
[0031] During formation of the main wellbore 58 and assembly of the casing string 52 , the casing section 14 may be inserted into the casing string 52 at a desired location and advanced into the wellbore while in the closed configuration. When the casing section 14 is in the closed configuration, it can function in substantially the same manner as an otherwise standard section of casing or tubing within the casing string 52 , thereby allowing the drill string and other equipment to be moved along and through the length of the casing section 14 in a substantially unrestricted manner until such time as it is desired to form the lateral borehole or wellbore 64 ( FIG. 1 ). The casing section 14 is inserted into the casing string 52 and advanced along the wellbore 58 until it is located at a desired intersection of the lateral borehole 64 and the main wellbore 58 , at which point the casing section 14 is cemented or otherwise secured within the wellbore 58 .
[0032] Referring also to FIG. 5 , the distal end 98 of the inner sleeve 86 includes an alignment portion 122 formed on an inner surface 126 of the inner sleeve wall 106 . The illustrated alignment portion 122 may include an axially-extending slot 130 formed within a reduced-diameter portion 134 of the inner sleeve wall 106 . Angled cam surfaces 138 may be positioned at a proximal end of the slot 130 and extend in a proximal and radial direction to function as alignment aids, as discussed further below. In other embodiments, the alignment portion 122 may be or include an aperture in the inner sleeve wall 106 , a projection extending inwardly from the inner sleeve wall 106 , a curved slot or curved projection that defines a more elongated cam surface 138 , combinations thereof, and the like. Moreover, in still other embodiments the alignment portion 122 may be located at the proximal end 94 of the inner sleeve 86 , or at substantially any location along the length of the inner sleeve 86 .
[0033] Referring now to FIGS. 6 through 8 , the inner sleeve 86 is moveable, for example rotatable, with respect to the outer sleeve 66 from the first position of FIGS. 2 through 4 in which the inner window 110 is misaligned with the outer window 82 to a second position shown in FIGS. 5 through 7 in which the inner window 110 is substantially aligned with the outer window 82 . When the inner sleeve 86 is in the second position, the casing section 14 is in a second, open configuration whereby the interior of the casing section 14 is exposed or opened to the exterior of the casing section 14 . In this way, tools and other equipment can be guided or diverted out of the main wellbore and against the now exposed inner surface of the main wellbore 58 (see FIG. 1 ), for example to cut or otherwise form a lateral or secondary borehole or wellbore 64 that diverges away from the main wellbore 58 . As shown, the size and shape of the inner window 110 is substantially similar to and generally compliments the size and shape of the outer window 82 to provide an elongated window or casing exit that extends along a substantial majority of the casing section 14 .
[0034] Generally speaking, the sizes of the inner window and the outer window 82 will be determined by the size of the system and the outer diameters of the mills and/or drill bits used to form the lateral wellbore 64 . For example, a chord length Li ( FIGS. 4 and 7 ) of the inner opening should be larger than the outer diameter of the largest mill or drill bit that will be used to form the lateral wellbore, and a chord length Lo ( FIGS. 4 and 7 ) of the outer opening should be slightly larger than the chord length Li.
[0035] To move the inner sleeve 86 from the first position in which the casing section 14 is in the closed configuration to the second position in which the casing section 14 is in the open configuration, suitably configured equipment may be run down the casing string 52 to the casing section 14 . Such equipment is provided with an alignment feature configured to engage with the alignment portion 122 provided on the inner sleeve 86 . The equipment is then operated to apply a force to the alignment portion 122 that in turn causes movement, for example rotation, of the inner sleeve 86 with respect to the outer sleeve 66 until the inner sleeve 86 has been moved to the second position and the inner window 110 is brought into substantial alignment with the outer window 82 .
[0036] Referring also to FIG. 9 , although substantially any type of down hole equipment can be used to adjust the casing section 14 from the closed configuration to the open configuration, in the illustrated embodiment, a deflector tool 142 in the form of a whipstock assembly may be configured to engage the alignment portion 122 of the inner sleeve 86 and thereby move the inner sleeve 86 from the first position to the second position. It should be appreciated that deflector tools 142 other than the illustrated whipstock assembly, such as a completion deflector, or a combination deflector that incorporates both a whipstock face and a completion deflector into one deflector face can also be utilized in combination with the casing section 14 and the general teachings and concepts discussed herein. At least one advantage of using the deflector tool 142 to move the inner sleeve 86 is that once the inner sleeve 86 has been moved and the casing section 14 is in the open configuration, the deflector tool 142 is already in position to deflect additional drilling equipment through the opened outer window 82 to begin drilling the lateral borehole 64 .
[0037] The deflector tool 142 includes a proximal portion 146 that includes an angled deflector surface 150 , an intermediate portion including a second alignment portion or alignment section 154 configured to engage the alignment portion 122 , and distal latching portion 158 for fixedly engaging the distal end 74 of the outer sleeve 66 . As can be appreciated, the deflector tool 142 is sized and configured to fit within the casing section 14 .
[0038] Referring also to FIG. 10 , one exemplary embodiment of the alignment section 154 includes an elongated and radially outwardly extending projection or lug 162 sized and configured to fit within the slot 130 of the alignment portion 122 of the inner sleeve 86 (see FIG. 5 ). The lug 162 may include angled lead-in surfaces 166 at each end that cooperate with the cam surfaces 138 ( FIG. 5 ) of the alignment portion 122 to aid in rotational alignment of the inner sleeve 86 with the deflector tool 142 as the deflector tool 142 is advanced into the casing section 14 . As best shown in FIG. 9 , the lug 162 extends radially in a direction that is substantially diametrically opposed to the direction in which the deflector surface 150 faces. In other embodiments, the configuration of components may be reversed such that the alignment portion 122 of the inner sleeve 86 includes the lug 162 and the alignment section 154 of the deflector tool 142 defines the slot 130 . Still other embodiments may include a more extensive arrangement of cam surfaces on one or both of the alignment portion 122 and the alignment section 154 such that axial movement of the deflector tool 142 into the casing section 14 engages the cam surfaces and causes the inner sleeve 86 to rotate from the first position to the second position. In still other embodiments, the lug 162 may be moveable between an extended position similar to the position illustrated in FIG. 10 , and a retracted position whereby the lug 162 is substantially flush with the surrounding surfaces of the deflector tool 142 . In such embodiments, once the deflector tool 142 is advanced to an appropriate location in the casing section 14 , the lug 162 could be extended for engagement with or fitment within a suitably configured alignment portion 122 provided on the inner sleeve 86 .
[0039] FIG. 11 shows the deflector tool 142 axially advancing into the casing section 14 with the casing section 14 in the closed configuration. In the position shown, the lug 162 is still slightly uphole of the alignment portion 122 and the slot 130 . The lug 162 is also substantially radially aligned with the location of the outer window 82 and substantially diametrically opposed with respect to the inner window 110 . Although not shown, the deflector surface 150 is facing toward the inner window 110 .
[0040] Referring now to FIG. 12 , the deflector tool 142 has been axially advanced to insert the lug 162 into the slot 130 of the alignment portion 122 . The deflector tool 142 has also been rotated about 180 degrees to move the inner sleeve 86 from the first position to the second position, thereby changing the casing section 14 from the closed configuration to the open configuration. As shown, the inner window 110 has been brought into substantial alignment with the outer window 82 , and the deflector surface 150 is facing through the now opened inner and outer windows 110 , 82 . In alternative embodiments, one or both of the deflector tool 142 and the alignment portion 122 may be configured with an appropriate arrangement of cam surfaces such that as the deflector tool 142 is axially advanced into the alignment portion 122 , the cam surfaces cause the inner sleeve 86 to rotate from the first position to the second position. In such alternative embodiments, the deflector tool 142 can be advanced into the casing section 14 with the deflector surface 150 facing toward the outer window 82 . Still other embodiments may rely on a combination of cam surfaces and rotation of the deflector tool 142 to fully rotate the inner sleeve 86 from the first position to the second position.
[0041] In addition, latching cleats 170 on the latching portion 158 have been extended radially outwardly for engagement with the distal end 74 of the outer sleeve 66 . In the illustrated embodiments, the latching cleats 170 may be extended after the deflector tool 142 has been rotated to move the inner sleeve 86 from the first position to the second position. In other embodiments the latching portion 158 may be rotatable with respect to the remainder of the deflector tool 142 , in which case the latching cleats 170 may optionally be extended after the deflector tool 142 has been advanced axially into the casing section, but before the deflector tool 142 is rotated to move the inner sleeve 110 to the second position.
[0042] Referring to FIG. 13 , when the casing section 14 is in the open configuration, the entire deflector surface 150 is substantially exposed to the exterior of the casing section 14 . More specifically, the axial length of the inner and outer windows 110 , 82 are greater than the axial length of the deflector surface 150 . In this way, tools guided through the casing section 14 and into engagement with the deflector surface 150 may be diverted through the casing exit defined by the inner and outer windows 110 , 82 and against the interior surface of the main wellbore to form or enter into an already formed lateral wellbore.
[0043] Therefore, the present invention is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered, combined, or modified and all such variations are considered within the scope and spirit of the present invention. The invention illustratively disclosed herein suitably may be practiced in the absence of any element that is not specifically disclosed herein and/or any optional element disclosed herein. While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components and steps. All numbers and ranges disclosed above may vary by some amount. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces. If there is any conflict in the usages of a word or term in this specification and one or more patent or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted. | Disclosed are systems and methods for providing a casing exit. One method includes introducing into a wellbore a casing section having an outer sleeve and an inner sleeve rotatably received within the outer sleeve, the outer sleeve defining an outer window and the inner sleeve defining an inner window rotationally alignable with the outer window, wherein the inner sleeve defines a first alignment portion engageable to rotate the inner sleeve, advancing the casing section to a wellbore location with the inner window rotationally misaligned with the outer window, extending a deflector tool within the casing section such that a second alignment portion provided on the deflector tool engages the first alignment portion, and rotating the deflector tool such that the inner sleeve rotates with respect to the outer sleeve and moves the casing section into an open configuration where the inner window is rotationally aligned with the outer window. | 4 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present patent application claims the benefit of U.S. Provisional Patent Application 60/729,111, filed Oct. 20, 2006, which is assigned to the assignee of the present application and is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to online search engines, and specifically to techniques for rules-based online content presentation.
BACKGROUND OF THE INVENTION
[0003] Many search engines provide content manipulation tools that modify a result set in order to merchandise particular items. Most basically, search engines present results ranked by their relevance to the user's query, determined by information-retrieval considerations and search algorithms. In addition, some search engines modify the ranking of the results based on additional considerations, such as business considerations. For example, in response to the query “bicycle,” a search engine may choose to promote a certain brand within the search results, and display some of the models of this brand among the top ten results.
SUMMARY OF THE INVENTION
[0004] Embodiments of the present invention enable rules for manipulating content to be triggered by search results that are returned in response to a query posed by a user. In some of these embodiments, a search and navigation system permits a manager of the content to identify characteristics that may occur in the query results, and to specify rules to be applied by the system when the characteristics appear in the results. Typically, the rules define actions to be taken by the system, such as modifying the order of the result set, adding items to the set that do not necessarily satisfy the query, or presenting content to the user that is outside the scope of the query. This approach expands the range of tools available to the manager for inferring types of content that could be of interest to the user and thus bringing the content to the user's attention.
[0005] There is therefore provided, in accordance with an embodiment of the present invention, a computer-implemented method for delivering content, including:
[0006] specifying a rule having a trigger and defining a content presentation action;
[0007] receiving a search query from a user;
[0008] generating a result set in response to the search query;
[0009] identifying at least one characteristic of the result set;
[0010] comparing the at least one characteristic to the trigger; and
[0011] if the at least one characteristic satisfies the trigger, presenting the content as specified by the content presentation action that is defined by the rule.
[0012] For some queries, the at least one characteristic is not included in the search query. For some applications, the search query, the at least one characteristic, and the trigger include respective attribute-value pairs. For some applications, the at least one characteristic includes at least one ordered characteristic.
[0013] In an embodiment of the present invention, identifying the at least one characteristic includes determining that the at least one characteristic dominates the result set. For example, determining that the at least one characteristic dominates the result set may include determining that the at least one characteristic characterizes at least a threshold percentage of items in the result set. Alternatively, determining that the at least one characteristic dominates the result set may include determining that the at least one characteristic characterizes at least a threshold number of items in the result set.
[0014] In an embodiment of the present invention, identifying includes assessing, for each of a plurality of characteristics that include the at least one characteristic, a number of items in the result set that are characterized by the characteristic. For some applications, the plurality of characteristics includes only characteristics included in the trigger.
[0015] In an embodiment of the present invention, the trigger specifies a threshold number of items, the at least one characteristic of the result set specifies a number of items in the result set, and presenting the content includes presenting the content as specified by the content presentation action that is defined by the rule responsively to a comparison between the number of items and the threshold number of items. Furthermore, presenting the content may include presenting the content as specified by the content presentation action that is defined by the rule both (a) responsively to the comparison, and (b) upon finding that the query contains a set of one or more characteristics.
[0016] For some applications, the trigger specifies a set of one or more items, and comparing the at least one characteristic to the trigger includes determining whether or not the result set contains the items in the specified set.
[0017] For some applications, identifying the at least one characteristic of the result set includes identifying a first characteristic of the result set, and a second characteristic of the result set that refines the first characteristic, and identifying the second characteristic, but not the first characteristic, as the at least one characteristic of the result set.
[0018] There is further provided, in accordance with an embodiment of the present invention, a computer-implemented method for delivering content, including:
[0019] specifying a rule, which has a trigger and a threshold and defines a content presentation action;
[0020] receiving a search query from a user;
[0021] generating a query result set by searching a corpus of data for items that satisfy the search query;
[0022] generating a trigger result set by searching the corpus of data for items that satisfy the trigger;
[0023] determining a level of intersection between the query result set and the trigger result set; and
[0024] if the level of intersection is greater than the threshold, presenting the content as specified by the content presentation action defined by the rule.
[0025] For some applications, the search query and the trigger each include at least one attribute-value pair.
[0026] In an embodiment of the present invention, determining the level of intersection includes setting the level of intersection equal to a quotient of (i) an assessment of a number of items in a set formed by an intersection of the query and trigger result sets divided by (ii) a divisor, and the divisor is selected from the group consisting of: an assessment of a number of items in the query result set, an assessment of a number of items in the trigger result set, and a sum of the assessment of the number of items in the query result set and the assessment of the number of items in the trigger result set.
[0027] Alternatively, determining the level of intersection includes setting the level of intersection equal to an assessment of a number of items in a set formed by the intersection of the query and trigger result sets.
[0028] For some applications, generating the trigger result set includes making a record of the trigger result set, and determining the level of intersection includes determining the level of intersection between the query result set and the record of the trigger result set.
[0029] There is still further provided, in accordance with an embodiment of the present invention, apparatus for delivering content, including:
[0030] a search engine, which is configured to receive a search query from a user, and to generate a result set in response to the search query; and
[0031] a result processor, which is configured to receive a specification of a rule having a trigger and defining a content presentation action, to identify at least one characteristic of the result set, to compare the at least one characteristic to the trigger, and, if the at least one characteristic satisfies the trigger, to present the content as specified by the content presentation action that is defined by the rule.
[0032] There is additionally provided, in accordance with an embodiment of the present invention, apparatus for delivering content, including:
[0033] a result processor, which is configured to receive a specification of a rule, which has a trigger and a threshold and defines a content presentation action; and
[0034] a search engine, which is configured to receive a search query from a user, to generate a query result set by searching a corpus of data for the items that satisfy the search query, and to generate a trigger result set by searching the corpus of data for the items that satisfy the trigger,
[0035] wherein the result processor is configured to determine a level of intersection between the query result set and the trigger result set, and, if the level of intersection is greater than the threshold, to present the content as specified by the content presentation action defined by the rule.
[0036] There is yet additionally provided, in accordance with an embodiment of the present invention, a computer software product for delivering content, the product including a computer-readable medium in which program instructions are stored, which instructions, when read by a computer, cause the computer to receive a specification of a rule having a trigger and defining a content presentation action, to receive a search query from a user, to generate a result set in response to the search query, to identify at least one characteristic of the result set, to compare the at least one characteristic to the trigger, and, if the at least one characteristic satisfies the trigger, to present the content as specified by the content presentation action that is defined by the rule.
[0037] There is also provided, in accordance with an embodiment of the present invention, a computer software product for delivering content, the product including a computer-readable medium in which program instructions are stored, which instructions, when read by a computer, cause the computer to receive a specification of a rule, which has a trigger and a threshold and defines a content presentation action, to receive a search query from a user, to generate a query result set by searching a corpus of data for items that satisfy the search query, to generate a trigger result set by searching the corpus of data for items that satisfy the trigger, to determine a level of intersection between the query result set and the trigger result set, and, if the level of intersection is greater than the threshold, to present the content as specified by the content presentation action defined by the rule.
[0038] The present invention will be more fully understood from the following detailed description of embodiments thereof, taken together with the drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] FIG. 1 is a schematic illustration of a search and navigation system 10 , in accordance with an embodiment of the present invention;
[0040] FIG. 2 is a flow chart that schematically illustrates a method for performing result-characteristics-based triggering, in accordance with an embodiment of the present invention; and
[0041] FIG. 3 is a flow chart that schematically illustrates a method for performing result-set-based triggering, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
Overview
[0042] Embodiments of the present invention enable rules for manipulating content to be triggered by search results that are returned in response to a query posed by a user. In some of these embodiments, a search and navigation system permits a manager of the content to identify characteristics that may occur in the query results, and to specify rules to be applied by the system when the characteristics appear in the results. Typically, the rules define actions to be taken by the system, such as modifying the order of the result set, adding items to the set that do not necessarily satisfy the query, or presenting content to the user that is outside the scope of the query. This approach expands the range of tools available to the manager for inferring types of content that could be of interest to the user and thus bringing the content to the user's attention. For some applications, such content manipulation is performed in order to merchandise items in the result set, or other items not found in the result set.
[0043] In some embodiments of the present invention, the system identifies characteristics of the result set that dominate the result set. Characteristics are considered dominant if they characterize at least a threshold percentage of the items in the result set, or at least a threshold number of the items in the result set.
[0044] These results-based content manipulation techniques enable a manager of the content to perform desired content manipulation actions based on characteristics of items for which a user is searching, even if these characteristics do not appear in the user's query. The manager does not need to define specific triggers for every possible query characteristic that may be associated with a desired content manipulation action.
[0045] The following example illustrates some of the differences between these techniques of the present invention and conventional query-based content presentation techniques. Assume a trigger of a content presentation rule is defined as the attribute-value pair brand:Sony®. Using conventional query-based techniques, at least the following attribute-value-based queries would produce a match with the trigger: (a) brand:Sony, and (b) product:stereo AND brand:Sony, and the following queries would fail to produce a match: (c) brand:Toshiba®, and (d) product:stereo.
[0046] Using these techniques of the present invention, the above-mentioned queries (a) and (b) would also produce a match, because all of the items in the result set are characterized by brand:Sony, and query (c) would still fail to produce a match, because none of the results for brand:Toshiba are characterized by brand:Sony. However, in contrast to conventional query-based content presentation techniques, query (d) (product:stereo) would also produce a match if the items in the result set are dominated by Sony, e.g., if at least 40% of the items in the result set are characterized by brand:Sony, assuming a threshold setting of 40%. These techniques thus enable the manager to determine that the user has a potential interest in Sony, which interest was not detectable in the information provided by the query alone. The hypothetical connection in this example between stereo products and the particular brand is entirely data-driven.
[0047] In some embodiments of the present invention, the system generates (a) a query result set in response to a user query provided as input to the search engine, and (b) a trigger result set in response to a trigger provided as a query input to the search engine. The system performs a content manipulation action upon finding a threshold level of intersection between the query result set and the trigger result set.
System Description
[0048] FIG. 1 is a schematic illustration of a search and navigation system 10 , in accordance with an embodiment of the present invention. System 10 comprises a search engine 20 , a result processor 22 , an interface, such as a web server 24 , and a memory 26 . System 10 provides searching and navigation of items stored in memory 26 . Typically, system 10 comprises one or more standard computer servers with appropriate memory, communication interfaces and software for carrying out the functions prescribed by the present invention. This software may be downloaded to the system in electronic form over a network, for example, or it may alternatively be supplied on tangible media, such as CD-ROM.
[0049] A user, such as a customer, uses a workstation 30 , such as a personal computer, to remotely access system 10 via a wide-area network (WAN) 32 , such as the Internet. Typically, a web browser 34 of workstation 30 communicates with web server 24 . The web browser facilitates entry of search queries, and displays search results.
[0050] Result processor 22 implements one or more content presentation rules, which include respective triggers and content presentation actions to be performed upon satisfaction of the triggers. Such content presentation actions may include, for example, modifying the order of the result set, adding items to the set that do not necessarily satisfy the query, or presenting content to the user that is outside the scope of the query. System 10 presents content associated with the result set, as specified by the content presentation actions corresponding to the satisfied triggers of the rules.
[0051] Each of the triggers comprises a set of one or more characteristics that characterize items in memory 26 . The characteristics are typically expressed as one or more attribute-value pairs (notated herein as a:v), one or more free text searches, or a combination of attribute-value pairs and free text searches. Memory 26 , or another element of system 10 , contains at least one index that associates characteristics with items in the memory. Memory 26 may be part of system 10 (such as part of one or more of search engine 20 and/or result processor 22 ), or may be distributed in other physical locations.
[0052] For applications in which the characteristics are expressed as attribute-value pairs, each trigger can be expressed as follows:
t=a 1 :v 1 operator a 2 :v 2 , . . . , operator a n :v n (Equation 1)
wherein a i is an attribute and v 1 is a value of a i , and the operators are typically Boolean operators, such as AND, OR, NOT, and parentheses. The same attribute may appear more than once in a given trigger, with each occurrence having a different value. For some applications, additional attribute-value pairs are provided to control the results of a query, which pairs are not directly related to attributes of items in memory 26 . For example, such attribute-value pairs may indicate a desired sort order, a desired page number, or a desired currency for displaying prices. Furthermore, attribute-value pairs may include additional information, such as display information. For example, the attribute-value pair brand:14:‘Sony’may indicate a that the attribute “brand” has as its value a brand code of 14, which is to be displayed as “Sony.”
[0053] For some applications, free text searches are expressed as attribute-value pairs, in which the attribute is a generic indicator of a free text search, and the value is the free text. Alternatively, the attribute name is not an actual specific attribute, but instead indicates the kind of free search to be carried out, e.g., a search by author, or a search by title. For example, the author search may actually refer to author first name and author last name fields.
[0054] Content presentation rules are expressed most simply as (trigger, action). (For some applications, such rules have more complex structures, such as the specification of a plurality of actions, or the use of a Boolean expression including a plurality of triggers.) Result processor 22 evaluates the trigger by determining whether appropriate attribute-value pairs of the trigger, as specified by the trigger's Boolean operators, match at least one attribute-value pair of an input, such as a query, or a characterization of a result set, as described hereinbelow. If so, the trigger is true, the rule is said to fire, and the action is performed; if not, the trigger is false, the rule does not fire, and the action is not performed. (For triggers that simply include a list of one more attribute-value pairs related to one another by an implied AND, the result processor evaluates the trigger by determining whether each attribute-value pair of the trigger matches at least one attribute-value pair of the input.)
[0055] For hierarchical attributes, a trigger characteristic a:v is considered to match an input characteristic a:v′ if V′ refines v, i.e., the set of items characterized by a:v′ is a subset of the set of items characterized by a:v. For some applications, a rule is triggered if the value v′ of an input characteristic a:v′ refines a value v of a trigger characteristic a:v.
[0056] For ordered attributes, which have a fully ordered domain of values, such as price or date, a trigger characteristic a:[n 1 ,n 2 ] is considered to match an input characteristic a:[n 1 ′,n 2 ′] if [n 1 ′,n 2 ′] is a sub-range of [n 1 ,n 2 ], i.e., n 1 <=n 1 ′ and n 2 ′<=n 2 . For some applications, for free text attributes, a trigger characteristic a:v is considered to match an input characteristic a:v′ if v is identical to v′, or if there is a linguistic association between v and v′, as is known in the search engine art. Alternatively, result-set-based triggering can be used for a similar purpose, without resorting to defining satisfaction for individual trigger components.
[0057] Memory 26 contains one or more data structures including items and information describing the items, such as attributes of the items. For example, the data structures may include one or more indices or tables having entries, each of which includes an attribute-value pair and an associated item. The tables may be stored in an multi-dimensional array, a linked list, a link list of arrays, or another appropriate data structure known in the art. Alternatively or additionally, memory 26 may comprise one or more databases, such as relational databases. Memory 26 generally further includes data structures that define relationships among at least some of the attribute-value pairs, such as hierarchical relationships.
[0058] Reference is made to FIG. 2 , which is a flow chart that schematically illustrates a method for performing result-characteristics-based triggering, in accordance with an embodiment of the present invention. Result processor 22 uses this method to evaluate triggers 48 against input characteristics that include (a) a query 50 , and (b) inferred characteristics of the result set for the query. Alternatively, the input characteristics include only the inferred characteristics of the result set, and not query 50 .
[0059] The method receives as input query 50 , which, as described hereinabove, is typically expressed as attribute-value pairs, attribute-range-value pairs, and/or attribute-free text pairs. At a search step 52 , search engine 20 ( FIG. 1 ) searches query 50 against memory 26 , and outputs a result set 54 containing zero or more items from memory 26 .
[0060] Result processor 22 begins the characterization of the result set by assessing, for each attribute-value pair, the number of items in result set 54 that are characterized by the attribute-value pair, at a result set characterization step 56 . Such assessing typically comprises counting, either exactly or approximately, the number of items. For some applications, the result processor performs such assessing for all attribute-value pairs that have been indexed in memory 26 , while for other applications, the result processor performs such assessing only for attribute-pairs that are included in at least one of triggers 48 . In order to facilitate such assessing, memory 26 typically includes an index, such as of (items, attribute names) mapped to attribute values. It is noted that often more than one attribute-value pair per attribute is assessed. The result of the characterization is a set 58 of characteristics (e.g., attribute-value pairs) and corresponding assessments of items from result set 54 that map to the characteristics.
[0061] For hierarchical attributes, such as those that define categories, result processor 22 optionally characterizes each item by the most specific attribute value that is applicable to the item. In other words, if an item is characterized by both attribute-value pair a:v and a:v′, wherein v′ refines v, result processor 22 characterizes the item by a:v′ rather than a:v, assuming that v′ is above the applicable threshold.
[0062] At a threshold comparison step 60 , result processor 22 compares the assessments of each attribute of set 58 to one or more thresholds 62 . Thresholds 62 are specified globally, per attribute, per trigger 48 , or per each attribute of each trigger 48 . For some applications, the thresholds are expressed as item assessments, such as exact or approximate counts. For some applications, the thresholds are expressed as a percentage of the total number of items in result set 54 (or, equivalently, a range from 0 to 1, or another ratio). For example, the percentage may be at least 40%, such as at least 50%, 60%, 70%, or 80%. Alternatively or additionally, all or a portion of the thresholds are expressed as absolute numbers. Result processor 22 outputs a set 64 of those characteristics of set 58 that exceed the threshold(s) (as mentioned above, when trigger-specific thresholds are provided, this comparison is performed using the trigger-specific thresholds). The result processor thus identifies one or more characteristics that dominate result set 54 . For some applications, the result processor is configured to identify only a subset of the characteristics found, such as a single dominant characteristic (such as the most dominant characteristic), even in result set characterizations in which multiple characteristics are found. Alternatively, for some applications, the result processor is configured to identify only a single dominant characteristic per attribute.
[0063] At a trigger evaluation step 66 , result processor 22 evaluates each of triggers 48 against (a) set 64 of the characteristics that exceed the threshold(s), and (b) query 50 . Alternatively, the result processor evaluates trigger 48 only against set 64 . Such evaluation is performed as described hereinabove with reference to FIG. 1 . Based on this evaluation, the result processor outputs a set 70 of satisfied triggers. At a rule application step 72 , the system performs appropriate content presentation actions for the satisfied triggers, based on the content presentation rules, as described hereinabove, and presents content to the user as specified by the rules, at a content presentation step 74 . Typically, such content relates to at least a portion of result set 54 , and includes additional content as specified by the rules.
[0064] For some applications, a trigger is satisfied upon finding that result set 54 is not dominated by the one or more characteristics of the trigger. For some applications, a trigger is satisfied upon finding that result set 54 contains exactly a certain number of items characterized by the one or more characteristics of the trigger, or less than a threshold number of items characterized by the one or more characteristics of the trigger.
[0065] In an embodiment of the present invention, the result-characteristics-based triggering described hereinabove with reference to FIG. 2 supports ordered attributes. As mentioned above with reference to FIG. 1 , an ordered-attribute trigger takes the form of a:[n 1 ,n 2 ], wherein n 1 and n 2 are the lower and upper bounds, respectively, of the range of values of the attribute. Ordered attributes commonly include price and date. The attribute-value pair for any single given item in memory 26 is expressed as a:n, i.e., the item typically has only a single value n for the attribute a, e.g., a price of $10.
[0066] For supporting ordered attributes, the method of FIG. 2 includes, at an ordered attribute characterization step 80 , further characterizing those characteristics of set 58 which are ordered (as mentioned above, set 58 is produced at result set characterization step 56 ). Such further characterization results in a set 82 of range characteristics and corresponding counts of items from result set 54 that map to the range. In other words, set 82 includes one or more attribute-value ranges a:[n 1 ,n 2 ] and corresponding counts. At threshold comparison step 60 , result processor 22 compares the counts of each attribute-value range of set 82 to thresholds 62 . Attribute-value ranges having a count that exceeds an appropriate threshold (either in absolute terms, or as a percentage, as described hereinabove with reference to step 60 ) are included in output set 64 .
[0067] In accordance with a first technique for characterizing ordered attributes at step 80 , result processor 22 receives as input a set of desired ordering thresholds 84 . Each of ordering thresholds 84 are typically expressed as a percentage of the total items in result set 54 . Optionally, one or more of thresholds 62 serve as one or more of ordering thresholds 84 . For each ordered attribute a:n in set 58 and each ordering threshold 84 , result processor 22 produces one or more attribute-value ranges a: [n 1 ,n 2 ] by (a) setting n 1 equal to n, and (b) setting n 2 equal to the lowest possible value of attribute a greater than n 1 such that the quotient of (i) the sum of counts for a:n in set 58 over all n in [n 1 ,n 2 ] divided by (ii) the total number of items in result set 54 , is greater than the ordering threshold. Alternatively n 2 is set to n, or n 1 and n 2 are set such that n falls between n 1 and n 2 , such as at the midpoint of n 1 and n 2 . Result processor 22 outputs as set 82 each of the thus determined attribute-value ranges a: [n 1 ,n 2 ] and its corresponding count of items in result set 54 . It is noted that this technique for characterizing ordered attributes does not require knowledge of triggers 48 , and thus may be used for purposes other than triggering.
[0068] In accordance with a second technique for characterizing ordered attributes at step 80 , for each attribute-value range a: [n 1 ,n 2 ] included in at least one trigger 48 , result processor 22 sums the counts for a:n in set 58 over all n in [n 1 ,n 2 ], and outputs as set 82 each of the attribute value ranges and its corresponding summed count of items in result set 54 .
[0069] In accordance with a third technique for characterizing ordered attributes at step 80 , result processor 22 receives as input a set of desired ordering thresholds 84 , which are expressed as a set of ranges, or parameters for deriving a set of ranges from the ranges provided by triggers 48 . For example, the endpoints of the ranges may be multiples of $10, such that the ranges are [$0,$10], [$10,$20], [$20,$30], . . . Result processor 22 sums the counts for a:n in set 58 over all n in each of the ranges, and outputs as set 82 each of the attribute value ranges and its corresponding summed count of items in result set 54 .
[0070] In accordance with an alternative method for supporting ordered attributes, the method of FIG. 2 does not include step 80 . Instead, ordered attributes-value pairs included in set 58 are retained as single-value attribute-value pairs. At a combined threshold comparison step 60 and trigger evaluation step 66 , an attribute-range trigger is satisfied if the sum of the item counts falling within the range defined by the trigger exceeds a threshold value.
[0071] (It is noted that these attribute-range techniques produce precise results only if none of the unique items in result set 54 includes more than one value for a given attribute. Unique items could include more than value, for example, if a given item has two different SKUs with different respective prices. If any items include more than one value, summing the counts for such items may count a given unique item more than once. For some applications, result processor 22 is configured to ignore such overlaps, in which case the results of the method of FIG. 2 are approximate. Additional methods for counting can also provide approximate counts utilizing less processing power, such as random sampling. Alternatively, to arrive at precise results, the result processor determines unions of sets of items mapping to each characteristic, such that overlapping items are not counted more than once.)
[0072] In the embodiments described hereinabove, result processor 22 generally uses triggers that have the same structure as queries and inferred characteristics of the result set, such as attribute-value pairs. In an embodiment of the present invention, result processor 22 uses triggers of different types, which are particularly appropriate for evaluating result set characteristics, either alone or in combination with query characteristics. Such triggers typically do not include attribute-value pairs, and thus are evaluated independently of the characterization method described hereinabove with reference to FIG. 2 . For some applications, the implementation of the content presentation rules is modified to accommodate such triggers.
[0073] Such triggers may include, for example:
the result set contains more than, less than, or equal to a threshold number of items; the result set contains more than, less than, or equal to a threshold number of items, and the query contains one or more characteristics. For example, the trigger may be that the result set contains less than 10 items, and the query includes the attribute-value pair brand:Sony; and the result set contains or does not contain one or more particular items.
[0077] In an embodiment of the present invention, system 22 uses the characterization of a plurality of result sets to alert a manager of the content to potentially interesting patterns in the result sets and/or the search queries. Such alerts may include suggestions to the manager of new rules and/or new triggers. For example, the system may keep track of queries that produce result sets having fewer than a threshold number of items, such as empty result sets, and may notify the manager of frequent queries that are producing such result sets. The system may also notify the manager upon finding that the result sets of certain queries are dominated by certain characteristics that have not yet been included in any rules. Alternatively or additionally, the system creates reports and statistics that are enhanced with inferred characteristics.
[0078] Reference is now made to FIG. 3 , which is a flow chart that schematically illustrates a method for performing result-set-based triggering, in accordance with an embodiment of the present invention. This embodiment provides an alternative technique for satisfying triggers, and may be used separately or in combination with the triggering techniques described hereinabove.
[0079] The method receives as input query 100 , which, as described hereinabove, is typically expressed as attribute-value pairs, attribute-range-value pairs, and/or free text searches. At a search step 102 , search engine 20 applies a search algorithm to search memory 26 for items that satisfy the query, and outputs a query result set 104 for the query, which set contains zero or more items from memory 26 .
[0080] The method also receives as input a set of at least one trigger 106 , which, as described hereinabove, includes one or more characteristics, which are typically expressed as attribute-value pairs, attribute-range-value pairs, and/or free text searches. At a search step 108 , search engine 20 applies the search algorithm to search memory 26 for items that satisfy trigger 106 when the trigger is regarded as a query, and outputs a trigger result set 110 for the trigger. In other words, search engine 20 interprets trigger 106 as a query. For applications in which trigger 106 comprises a Boolean expression, as described hereinabove with reference to Equation 1, searching memory 26 includes evaluating the Boolean expression, as is known in the search engine art.
[0081] At an intersection evaluation step 112 , result processor 22 determines an intersection set 114 that includes all items that are found in both query result set 104 and trigger result set 110 . The content manager compares (a) the quotient of an assessment of the number of items in intersection set 114 divided by the number of items in query result set 104 with (b) a threshold 116 . For example threshold 116 may be at least 50%, such as at least 60% or 75%. (Alternatively, the divisor is an assessment of the number of items in trigger result set 110 , or the sum of the assessments of the number of items in the query and trigger result sets 104 and 110 .) The assessment of the number of items is typically performed by counting the number of items, either exactly or approximately. If the quotient is greater than threshold 116 , the result processor determines that trigger 106 is a satisfied trigger 118 . At a rule application step 120 , the system performs the appropriate content presentation action for satisfied trigger 118 , based on the content presentation rules, as described hereinabove, and presents content to the user as specified by the rules, at a content presentation step 122 .
[0082] Alternatively, at intersection evaluation step 112 , result processor 22 compares (a) an assessment of the number of items in intersection set 114 with (b) threshold 116 . The assessment of the number of items is typically performed by counting the number of items, either exactly or approximately. If the number of items is greater than threshold 116 , the result processor determines that trigger 106 has been satisfied.
[0083] Result processor 22 repeats steps 108 through 112 to evaluate each of a plurality of triggers 106 . A global threshold 116 may be used for evaluating the plurality of triggers 106 , or a separate trigger may be provided for each of the triggers.
[0084] For some applications, rather than determine trigger result set 110 separately for each received query 100 , system 22 makes a record of trigger result set 110 and uses the record for evaluating a plurality of queries 100 . For example, system 22 may cache trigger result set 110 for each trigger 106 , and reuse the cached result sets for evaluating a plurality of queries 100 . The cached result sets are recomputed or flushed from the cache upon changes to memory 26 or to trigger 106 . Alternatively, the system makes such a record using an index, a mapping, or a data structure, which provides, for each item in memory 26 , the triggers in whose trigger results the item appears.
[0085] In some embodiments of the present invention, one or more of the functions described herein as being performed by result processor 22 are instead performed by a module of search engine 20 .
[0086] It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof that are not in the prior art, which would occur to persons skilled in the art upon reading the foregoing description. | A computer-implemented method for delivering content is provided, including specifying a rule having a trigger and defining a content presentation action, and receiving a search query from a user. The method further includes generating a result set in response to the search query, identifying at least one characteristic of the result set, and comparing the at least one characteristic to the trigger. If the at least one characteristic satisfies the trigger, the content is presented as specified by the content presentation action that is defined by the rule. Other embodiments are also described. | 6 |
The invention relates to siloxane copolymers and more particularly to siloxane copolymers containing alkenyl groups and to a process for preparing the same The invention also relates to compositions which contain a siloxane copolymer containing alkenyl groups, an organopolysiloxane containing Si-bonded hydrogen atoms and a catalyst, and to the use of the compositions in preparing coatings which repel tacky subtances.
BACKGROUND OF THE INVENTION
It is known that organopolysiloxanes containing Si-bonded vinyl groups can be reacted with organopolysiloxanes containing Si-bonded hydrogen atoms in the presence of catalysts. However, such organopolysiloxanes containing Si-bonded vinyl groups are not readily available since they have to be prepared by hydrolysis from halovinylsilanes, and they can only be prepared with difficulty.
Organopolysiloxanes containing trimethylolethanediallyl ether, trimethylolpropane-diallyl ether or pentaerythritol-triallyl ether groups, which are described in U.S. Pat. No. 4,311,821 (published Jan. 19, 1982, C. Weitemeyer et al, Th. Goldschmidt AG), are more readily available. The linking of the trimethylolethane diallyl ether, trimethylolpropane-diallyl ether or the pentaery-thritol-triallyl ether is achieved by reaction of the hydroxyl group with an Si-bonded halogen or Si-bonded alkoxy group of an organopolysiloxane. The disadvantage is that the SiOC linkage thus obtained is relatively unstable to hydrolysis in comparison with an SiC linkage.
The reaction of an organic compound containing four aliphatic double bonds, such as, for example, tetraallyloxyethane, with a silane containing Si-bonded hydrogen in the presence of a catalyst which promotes the addition of an Si-bonded hydrogen atom to an aliphatic double bond is described in U.S. Pat. No. 4,208,319 (published Jun. 18, 1980, P. August et al, Wacker-Chemie GmbH). In this reaction, yields of organosilane containing 3 aliphatic double bonds of practically 100 percent of theory are obtained. The organosilanes thus obtained are used as reinforcing additives in compositions which are based on organic polymers and fillers and can be crosslinked by sulfur or free radicals.
An object of the present invention is to provide siloxane copolymers which contain alkenyl groups Another object of the present invention is to provide a simple process for preparing siloxane copolymers containing more than one alkenyl group on a silicon atom. A further object of the present invention is to provide siloxane copolymers containing more than one alkenyl group on a silicon atom which are stable to hydrolysis. A still further object of the present invention is to provide siloxane copolymers having more than one alkenyl group which rapidly crosslink with organopolysiloxanes containing Si-bonded hydrogen atoms in the presence of a catalyst which promotes the addition of Si-bonded hydrogen to an aliphatic double bond.
SUMMARY OF THE INVENTION
The foregoing objects and others which will become apparent from the following description are accomplished in accordance with this invention, generally speaking, by providing siloxane copolymers having alkenyl groups and contain (a) siloxane units of the formula ##STR1## in which R represents the same or different hydrocarbon radicals having from 1 to 18 carbon atom(s) per radical or halogenated hydrocarbon radicals having from 1 to 18 carbon atom(s) per radical R 1 is an alkyl radical having from 1 to 4 carbon atom(s) per radical which can be substituted by an ether oxygen atom, a is 0, 1, 2 or 3; b is 0, 1, 2 or 3; and the sum of a+b is not greater than 3;
(b) at least one siloxane unit, per molecule, of the formula ##STR2## in which R is the same as above; c is 0, 1 or 2; G represents a radical of the formula
--CH.sub.2 CHR.sup.2 CHR.sup.2 OY(OCHR.sup.2 CR.sup.2 ═CH.sub.2).sub.x-1
in which R 2 represents a hydrogen atom or a methyl radical; Y represents a trivalent, tetravalent, pentavalent or hexavalent hydrocarbon radical which has from 2 to 20 carbon atoms per radical and can be substituted by groups of the formula --OH; --OR 3 ; --OSiR 4 3 ; ##STR3## or --X; or can be interrupted by at least one oxygen atom or sulfur atom or one carbonyl group, or Y represents a trivalent radical of the formula
.tbd.P, .tbd.P═O or .tbd.SiR.sup.5,
in which R 3 represents an alkyl radical having from 1 to 6 carbon atom(s) per radical, R 4 represents a methyl, ethyl, isopropyl, tert-butyl or phenyl radical, X is a halogen atom and R 5 represents a monovalent hydrocarbon radical having from 1 to 8 carbon atoms(s) per radical, or Y represents a tetravalent element, such as ##STR4## and x is 3, 4, 5 or 6, and optionally (c) at least one unit, per molecule, selected from the group consisting of units of the formula ##STR5## in which R and c are the same as above, G 1 represents a radical of the formula ##STR6## in which R 2 , Y and x are the same as above.
DESCRIPTION OF THE INVENTION
The siloxane copolymers containing alkenyl groups preferably contain siloxane units of formula (I), at least one siloxane unit of formula (II) per molecule and at least one unit selected from the group consisting of units of the formulas (III), (IV) and (V) per molecule
The invention also relates to a process for preparing siloxane copolymers containing alkenyl groups, which comprises reacting an organic compound (1) containing more than two aliphatic double bonds of the general formula
Y(OCHR.sup.2 CR.sup.2 ═CH.sub.2).sub.x
in which R 2 , Y and x are the same as above, with an organopolysiloxane (2) containing at least one Si-bonded hydrogen atom per molecule in the presence of a catalyst (3) which promotes the addition of Si-bonded hydrogen to an aliphatic double bond, in which the ratio employed of the aliphatic double bond in the organic compound (1) to the Si-bonded hydrogen in the organopolysiloxane (2) is such that siloxane copolymers are obtained which contain alkenyl groups and have an average of more than two alkenyl groups of the formula
--OCHR.sup.2 CR.sup.2 ═CH.sub.2 ,
in which R 2 is the same as above.
Preferably, x is 3 or 4 and Y is a trivalent or tetravalent radical.
The organopolysiloxanes of this invention containing alkenyl groups preferably have a viscosity of from 5 to 5×10 5 mPa.s at 25° C., and more preferably from 50 to 50,000 mPa.s at 25° C.
Examples of radicals represented by R are alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, 1-n-butyl, 2-n-butyl, iso-butyl, tert-butyl, n-pentyl, isopentyl, neo-pentyl and tert-pentyl radical, hexyl radicals, such as the n-hexyl radical, heptyl radicals, such as the n-heptyl radical, octyl radicals, such as the n-octyl radical and iso-octyl radicals, such as the 2,2,4-trimethylpentyl radical, nonyl radicals, such as the n-nonyl radical, decyl radicals, such as the n-decyl radical, dodecyl radicals, such as the n-dodecyl radical, and octadecyl radicals, such as the n-octadecyl radical; cycloalkyl radicals, such as cyclopentyl, cyclohexyl and cycloheptyl radicals and methylcyclohexyl radicals; aryl radicals, such as the phenyl, naphthyl, anthryl and phenanthryl radical; alkaryl radicals, such as o-, m- and p-tolyl radicals, xylyl radicals and ethylphenyl radicals; and aralkyl radicals, such as the benzyl radical and the - and the -phenylethyl radicals The methyl radical is the preferred radical represented by R.
Examples of halogenated radicals represented by R are haloalkyl radicals, such as the 3,3,3-trifluoro-n propyl radical, the 2,2,2,2', 2',2'-hexafluoroisopropyl radical and the heptafluoroisopropyl radical, and haloaryl radicals, such as the o-, m- and p-chlorophenyl radicals.
Examples of alkyl radicals represented by R 1 are the methyl, ethyl, n-propyl, isopropyl, 1-n-butyl, 2-n-butyl, iso-butyl and tert-butyl radical. The methyl and ethyl radicals are the preferred radicals. Examples of alkyl radicals represented by R 1 which are substituted by an ether oxygen atom are the methoxyethyl and ethoxyethyl radical.
The R 2 radical is preferably a hydrogen atom.
Examples of alkyl radicals represented by R 3 are the methyl, ethyl, n-propyl, iso-propyl, 1-n-butyl, 2-n-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl and tert-pentyl radical and hexyl radicals, such as the n-hexyl radical.
Examples of radicals represented by R 5 are alkyl radicals such as the methyl, ethyl, n-propyl, iso-propyl, 1-n-butyl, 2-n-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl and tert-pentyl radical, hexyl radicals, such as the n-hexyl radical, heptyl radicals, such as the n-heptyl radical, octyl radicals, such as the n-octyl radical, and iso-octyl radicals, such as the 2,2,4-trimethylpentyl radical, alkenyl radicals, such as the vinyl and the allyl radical; cycloalkyl radicals, such as cyclopentyl, cyclohexyl and cycloheptyl radicals and methylcyclohexyl radicals; aryl radicals, such as the phenyl radical; alkaryl radicals, such as o-, m- and p-tolyl radicals, xylyl radicals and ethylphenyl radicals; and aralkyl radicals, such as the benzyl radical and the α- and β -phenethyl radicals.
Preferred siloxane copolymers containing alkenyl groups are those which contain
(a) siloxane units of the formula
R.sub.2 SiO (I')
(b) at least two siloxane units of the formula
GR.sub.2 SiO.sub.1/2 (II')
per molecule, and
(c) at least one unit of the formula
O.sub.1/2 R.sub.2 SiG.sup.1 SiR.sub.2 O.sub.1/2 (III')
in which R, G and G 1 are the same as above.
Examples of the organic compound (1) which contains more than two aliphatic double bonds and is employed in the process of this invention are those of the formula ##STR7## in which R 6 represents hydrogen or a radical of the formula ##STR8## and k is an average of from 2.5 to 3.5, and more prefereably about 2.9. The last mentioned compound and tetraallyloxyethane are the preferred examples.
Examples of the radical represented by Y are those of the formula ##STR9##
Processes for the preparation of the organic compound (1) are described in EP-B 46,731 (published 3 October 1984, F. Lohse et al, Ciba-Geigy AG).
The compound of the formula
(HOCH.sub.2).sub.4-k C(CH.sub.2 OCH.sub.2 CH═CH.sub.2).sub.k
in which k is 2.9, is commercially available, for example, from Shell AG, and is marketed as pentaerythritol-triallyl ether. The compound of the formula ##STR10## in which k is an average of from 2.5 to 3.5, and more preferably about 2.9, is obtained by reacting the above compound with acetic anhydride or isopropenyl acetate
The organopolysiloxanes (2) having at least one Si-bonded hydrogen atom which are preferably employed in the process of this invention are those of the general formula ##STR11## in which R is the same as above, e is 0 or 1, with an average of from 0.005 to 1.0; f is 0, 1, 2 or 3; with an average of from 1.0 to 2.0; and the sum of e+f is not greater than 3.
Organopolysiloxanes (2) having at least one Si-bonded hydrogen atom which are preferably employed in the process of this invention are those of the general formula
H.sub.d R.sub.3-d SiO(SiR.sub.2 O).sub.o (SiRHO).sub.p SiR.sub.3-d H.sub.d(VII)
in which R is the same as above, d is 0 or 1, o is 0 or an integer from 1 to 1000, and p is 0 or an integer of from 1 to 6.
The organopolysiloxanes (2) employed in the process of this invention preferably contain from 2 to 6 Si-bonded hydrogen atoms per molecule.
The organopolysiloxanes (2) having at least one Si-bonded hydrogen atom per molecule, preferably have a viscosity of from 0.5 to 20,000 mPa.s at 25° C., and more preferably from 5 to 1000 mPa.s at 25° C.
Preferred examples of organopolysiloxanes of formula (VII) are copolymers of dimethylhydrogensiloxane and dimethylsiloxane units, copolymers of dimethylhydrogensiloxane, dimethylsiloxane and methylhydrogensiloxane units, copolymers of trimethylsiloxane and methylhydrogensiloxane units and copolymers of trimethylsiloxane, dimethylsiloxane and methylhydrogensiloxane units.
Processes for preparing organopolysiloxanes having at least one Si-bonded hydrogen atom per molecule, including those of the preferred type, are generally known.
The organic compound (1) is employed in the process of this invention in amounts such that the aliphatic double bond in the organic compound (1) and the Si-bonded hydrogen in the organopolysiloxane (2) are present in a ratio of preferably from 1.5:1 to 20:1, and more preferably from 2:1 to 10:1. The organic compound (1) can be combined with the organopolysiloxane (2) almost as desired within very wide limits, depending on their functionality and their molecular weight. However, a ratio of C═C:SiH of greater than 20:1 leads exclusively to monohydrosilylation of the organic compound (1), which is not preferred.
The reaction of the organic compound (1), such as tetraallyloxyethane, with the organopolysiloxane (2), such as α,w-dihydrogendimethylpolysiloxane, in the presence of catalyst (3) proceeds in accordance with the following equation: ##STR12##
The course of the reaction and therefore the resulting end product depends on the ratio employed of the C═C double bond in the organic compound (1) to the Si-bonded hydrogen in the organopolysiloxane (2). Depending on the ratio of C═C:SiH employed, in which the ratio of C═C:SiH is always greater than 1, siloxane copolymers are obtained which contain, at the chain end and along the chain, free alkenyl groups of the formula
--OCHR.sup.2 CR.sup.2 ═CH.sub.2, such as --OCH.sub.2 CH═CH.sub.2 .
It is possible for branching to occur along the chain by further reaction of the free alkenyl groups along the chain with the Si-bonded hydrogen atoms of the organopolysiloxane (2).
The same catalysts which have been or could have been used heretofore for promoting the addition of Si-bonded hydrogen to an aliphatic double bond can also be employed as catalysts (3) which promote the addition of Si-bonded hydrogen to an aliphatic multiple bond in the process of this invention. Catalysts (3) are preferably a metal from the group of platinum metals, or a compound or a complex from the group of platinum metals Examples of such catalysts are metallic and finely divided platinum, which can be supported on carriers, such as silicon dioxide, aluminum oxide or active charcoal, compounds or complexes of platinum, such as platinum halides, for example PtCl 4 , H 2 PtCl 6 .6H 2 O, Na 2 PtCl 4 .4H 2 O, platinum-olefin complexes, platinum-alcohol complexes, platinum-alcoholate complexes, platinum-ether complexes, platinum-aldehyde complexes, platinum-ketone complexes, including reaction products of H 2 PtCl 6 .6H 2 O and cyclohexanone, platinum-vinylsiloxane complexes, such as platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complexes which contain or are free of detectable inorganically bonded halogen, bis-(gamma-picoline)-platinum dichloride, trimethylenedipyridineplatinum dichloride, dicyclopentadieneplatinum dichloride, dimethyl sulfoxide-ethylene-platinum(II) dichloride and reaction products of platinum tetrachloride with an olefin and primary amine or secondary amine or a primary and secondary amine in accordance with U.S. Pat. No. 4,292,434, such as the reaction product of platinum tetrachloride dissolved in 1-octene with sec-butylamine, or ammonium-platinum complexes according to EP-B 110,370.
Catalyst (3) is preferably employed in amounts of from 0.5 to 1000 ppm by weight (parts by weight per million parts by weight), and more preferably in amounts of from 2 to 50 ppm by weight, calculated as elemental platinum and based on the total weight of the organic compound (1) and organopolysiloxane (2).
The process of this invention is preferably carried out at the pressure of the surrounding atmosphere, that is, for example, under 1020 hPa (absolute), but it can also be carried out under higher or lower pressures. The process of this invention is also preferably carried out at a temperature of from 50° C. to 150° C., and more preferably from 80° C. to 130° C.
Inert organic solvents can be used in the process of this invention, although the additional use of inert organic solvents is not preferred. Examples of inert organic solvents are toluene, xylene, octane isomers, butyl acetate, 1,2-dimethoxyethane, tetrahydrofuran and cyclohexane.
Excess organic compound (1) and inert organic solvent, if used, are preferably removed by distillation from the siloxane copolymers which contain alkenyl groups that have been prepared by the process of this invention.
If appropriate, the siloxane copolymers which contain alkenyl groups and have been prepared by the process of this invention are equilibrated with an organopolysiloxane (4).
The organopolysiloxanes (4) employed are preferably those selected from the group consisting of linear organopolysiloxanes containing terminal triorganosiloxy groups, of the formula
R.sub.3 SiO(SiR.sub.2 O).sub.r SiR.sub.3
in which R is the same as above and r is 0 or an integer having a value of from 1 to 1500, linear organopolysiloxanes containing terminal hydroxyl groups, of the formula
HO(SiR.sub.2 O).sub.s H
in which R is the same as above and s is an integer having a value of from 1 to 1500, cyclic organopolysiloxanes of the formula
(R.sub.2 SiO).sub.t
in which R is the same as above and t is an integer of from 3 to 12, and copolymers having units of the formula
R.sub.2 SiO and RSiO.sub.3/2
in which R is the same as above.
The ratio of the amount of organopolysiloxane (4) employed in the equilibration carried out, if appropriate, to siloxane copolymers containing alkenyl groups is determined merely by the desired content of alkenyl groups in the siloxane copolymers produced by the equilibration and by the mean chain length desired.
Basic catalysts which promote equilibration are preferably employed in the equilibration which is carried out, if appropriate. Examples of such catalysts are alkali metal hydroxides, such as sodium hydroxide and potassium hydroxide, trimethylbenzylammonium hydroxide and tetramethylammonium hydroxide. Alkali metal hydroxides are preferred. The alkali metal hydroxides are preferably used in amounts of from 50 to 10,000 ppm (parts per million) by weight, and more preferably from 500 to 2000 ppm by weight, based on the total weight of siloxane copolymer containing alkenyl groups and organopolysiloxane (4) employed. Although the use of acidic equilibration catalysts is possible, it is not preferred.
The equilibration which is carried out, if appropriate, is preferably carried out at 100° C. to 150° C. under the pressure of the surrounding atmosphere, that is at about 1020 hPa (absolute). However, higher or lower pressures can also be used if desired The equilibration is preferably carried out in from 5 to 20 percent by weight, of a water-immiscible solvent, such as toluene, based on the total weight of the particular siloxane copolymer containing alkenyl groups and the organopolysiloxane (4) employed. The catalyst can be rendered inactive before working up of the mixture obtained during equilibration.
The process of this invention can be carried out batchwise, semi-continuously or continuously.
Like the organopolysiloxanes containing Si-bonded vinyl groups, the siloxane copolymers of this invention containing alkenyl groups can be crosslinked with organopolysiloxanes containing Si-bonded hydrogen in the presence of hydrosilylation catalysts. The siloxane copolymers of this invention containing alkenyl groups can also be crosslinked with organic polymers containing mercapto groups.
The siloxane copolymers of this invention containing alkenyl groups are used in compositions which contain
(A) a siloxane copolymer which contains alkenyl groups and preferably contains units of formula (I), (II) and, optionally, at least one of the units of the formulas (III), (IV) or (V), preferably units of the formula (I'), (II') and (III'),
(B) an organopolysiloxane containing Si-bonded hydrogen atoms; and
(C) a catalyst which promotes the addition of Si-bonded hydrogen to an aliphatic double bond.
Organopolysiloxanes of formula (VI), preferably those of the formula
H.sub.d R.sub.3-d SiO(SiR.sub.2 O).sub.o (SiRHO).sub.qSiR.sub.3-d H.sub.d(VIII)
in which R is the same as above; d is 0 or 1; o is 0 or an integer of from 1 to 1000; and q is 0 or an integer from 1 to 50, preferably from 5 to 50, are preferably used as component (B).
The catalysts (3) mentioned above are preferably used as component (C).
The compositions can also contain other additives, such as (D) agents which delay the addition of Si-bonded hydrogen to an aliphatic double bond at room temperature. Such inhibitors are described, for example, in U.S. Pat. No. 3,933,880. Examples of these are acetylenically unsaturated alcohols, such as 3-methyl-1-butyn-3 ol, 1-ethynylcyclohexan -1-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-pentyn-3-ol and other similar compounds.
The compositions containing the siloxane copolymers of this invention are used in the preparation of coatings which repel tacky substances.
The compositions containing the siloxane copolymers of this invention are preferably crosslinked by ultraviolet light, ultraviolet light having wavelengths in the range of from 200 to 400 nm being preferred, and/or by heat, in which temperatures of from 20° C. to 100° C. are preferred. The ultraviolet light can be generated, for example, in xenon lamps or low pressure mercury, medium pressure mercury or high pressure mercury lamps. Light with a wavelength of from 400 to 600 nm, that is to say so-called "halogen light", is also suitable for crosslinking by means of light. The compositions containing the siloxane copolymers of this invention can be crosslinked by light in the visible range if commercially available photosensitizers are also used. Energy sources for crosslinking the compositions containing the siloxane copolymers of this invention by means of heat are furnaces, heating channels, heated rollers, heated plates or heat rays of the infrared range.
Examples of substrates onto which the coatings of this invention can be applied are those of paper, wood, cork, plastic films, such as, polyethylene films or polypropylene films, ceramic objects, glass, including glass fibers, metals, paperboard, including that made of asbestos, and woven and nonwoven cloth of natural or synthetic organic fibers.
The compositions containing the siloxane copolymers of this invention can be applied to the surfaces to be coated in any desired manner which is suitable and known in many instances for the production of coatings from liquid substances, for example by dipping, brushing, pouring, spraying, rolling on, printing, for example by means of an offset gravure covering device, or knife or doctor blade coating.
EXAMPLE 1
About 2.7 mg of platinum in a solution of platinum tetrachloride in 1-octene are added to 127 g of 1,1,2,2-tetraallyloxyethane. The mixture is heated to 110° C. and 78 g of an α,w-dihydrogendimethylpolysiloxane having a viscosity of 3.7 mm 2 ×s -1 at 25° C. and containing 0.32 percent by weight of Si-bonded hydrogen are added dropwise to this mixture at 110° C. under a nitrogen atmosphere, with stirring After the mixture has been stirred at 110° C. for about 3 hours, 98 percent of the Si-bonded hydrogen atoms of the α,ω-dihydrogendimethylpolysiloxane have reacted. All the volatile constituents are then removed by distillation at 120° C. under 10 -3 hPa (absolute). A clear yellowish oil having a viscosity of 61 mm 2 ×s -1 at 25° C. and an iodine number (number which specifies how many g of iodine are bonded by 100 g of substance) of 111 is obtained A ratio of dimethylsiloxane unit to allyloxy group of 1.75 can be seen for the dimethylpolysiloxane copolymer containing allyloxy groups from the 1 H-NMR spectrum.
EXAMPLE 2
About 89 g of 1,1,2,2-tetraallyloxyethane are mixed with 5.4 mg of platinum in a solution of platinum tetrachloride in 1-octene and the mixture is heated to 110° C. About 581 g of an α,w-dihydrogendimethylpolysiloxane having a chain length of 63 are added dropwise to this mixture at 110° C. over a period of 30 minutes under a nitrogen atmosphere, with stirring After the mixture has been stirred at 110° C. for about 3 hours, 98 percent of the Sio bonded hydrogen atoms of the α,w-dihydrogendimethylpolysiloxane have reacted All the volatile constituents are then removed by distillation at 120° C. under 10 -3 hPa. A dimethylpolysiloxane copolymer which contains allyloxy groups and has a viscosity of 380 mm 2 ×s -1 at 25° C. and iodine number of 19.6 is obtained A ratio of dimethylsiloxane unit to allyloxy group of 17 for the siloxane copolymer can be seen from the 1 H-NMR spectrum.
EXAMPLE 3
About 127 g of 1,1,2,2-tetraallyloxyethane are mixed with 10.8 mg of platinum in a solution of platinum tetrachloride in 1-octene and the mixture is heated to 110° C.. About 345 g of a copolymer containing methylhydrogensiloxane, dimethylsiloxane and trimethylsiloxane units which has a viscosity of 85 mm 2 ×s -1 at 25° C. and contains 0.058 percent by weight of Si-bonded hydrogen and an average of 3.2 Si-bonded hydrogen atoms per molecule are added dropwise to this mixture at 110° C. under a nitrogen atmosphere, with stirring. After the mixture has been stirred at 110° C. for about 22 hours, 96 percent of the Si-bonded hydrogen atoms of the copolymer have reacted All the volatile constituents are then removed by distillation at 120° C. under 10 -3 hPa (absolute). After filtration, 320 g of a clear yellow oil having a viscosity of 387 mm 2 ×s -1 at 25° C. and an iodine number of 24 are obtained. The siloxane copolymer thus obtained is non-crosslinked and is soluble in toluene to give a clear solution.
EXAMPLE 4
About 48 g of pentaerythritol-triallyl ether (obtainable from Shell; with an iodine number of 281) are mixed with 2.2 mg of platinum in a solution of platinum tetrachloride in 1-octene and the mixture is heated to 105° C. About 435 g of an α,w-dihydrogendimethylpolysiloxane which has a viscosity of 56 mm 2 ×s -1 at 25° C. and contains 0.046 percent by weight of Si-bonded hydrogen are added dropwise to this mixture. After the mixture has been stirred for about 7 hours, 98 percent of the Si-bonded hydrogen atoms of the α,w-dihydrogendimethylpolysiloxane have reacted. The volatile constituents are then removed by distillation at 120° C. under 10 -3 hPa (absolute). After filtration, 380 g of a clear liquid having a viscosity of 810 mm 2 ×s -1 at 25° C. and an iodine number of 11.0 are obtained. A ratio of dimethylsiloxane unit to allyloxy group of 28.2 for the siloxane copolymer containing allyloxy groups can be seen from the 1 H-NMR spectrum.
EXAMPLE 5
About 40.5 g of tetrakis(1-methyl-2-propenyloxy)silane, prepared by transesterification of tetramethoxysilane with sec-butanol, are mixed with 27 mg of platinum in a solution of platinum tetrachloride in 1-octene and the mixture is heated to 105° C. About 291 g of an α,w-dihydrogendimethylpolysiloxane having a chain length of 63 are added dropwise to this mixture at 105° C., while stirring. After the mixture has been stirred at 105° C. for about 5 hours, 95.5 percent of the Si-bonded hydrogen atoms of the α,w-dihydrogendimethylpolysiloxane have reacted. The volatile constituents are then removed by distillation at 120° C. under 10 -3 hPa (absolute). About 254 g of a clear product having a viscosity of 3860 mm 2 ×s -1 at 25° C. and an iodine number of 15 are obtained. A ratio of dimethylsiloxane unit to 1-methyl-2-propenyloxy group of 55 for the dimethylpolysiloxane copolymer containing 1-methyl-2-propenyloxy groups can be seen from the -1 H-NMR spectrum.
EXAMPLE 6
About 25.9 g of the product from Example 2 (20 mmol of allyloxy groups) are mixed with 34 mg of a 7 percent solution of platinum tetrachloride in 1-octene. About 1.2 g of a copolymer containing methylhydrogensiloxane and trimethylsiloxane units having a viscosity of 20 mm 2 ×s -1 (20 mmol of Si-bonded hydrogen) are added to the mixture. The mixture is then brushed onto paper at a thickness of about 2 μm. It hardens at 25° C. in less than 1 minute to give a non-tacky coating.
EXAMPLE 7
(a) About 395 g of an industrial mixture of pentaerythritol-di-, pentaerythritol-tri- and pentaerythritol-tetraallyl ether (corresponding to 2.0 mol of OH groups) are acylated with 250 g of isopropenyl acetate and 20 drops of concentrated H 2 SO 4 under reflux for 4 hours. Acetone is continuously distilled off over the top and the residue is subjected to fractional distillation in vacuo. About 412 g of a clear product which has an iodine number of 250 and, according to the -1 H-NMR spectrum, is free from methylol groups are obtained. (b) About 67.1 g (corresponding to 0.66 mol of C═C) of the acylated allyl ether mixture, the preparation of which is described in (a) above, are mixed with 2 mg of platinum in a solution of platinum tetrachloride in 1-octene and the mixture is heated to 110° C. About 384.6 g of an α,w-dihydrogendimethylpolysiloxane having a chain length of 52 are added dropwise to this mixture at 110° C. under a nitrogen atmosphere, with stirring After the mixture has been stirred at 110° C. for 5 hours, 98 percent of the Si-bonded hydrogen atoms of the α,w-dihydrogendimethylpolysiloxane have reacted. All the volatile constituents are then removed by distillation at 140° C. under 10 -3 hPa (absolute). About 380 g of a clear yellow siloxane copolymer which has a viscosity of 330 mm 2 ×s -1 and contains allyloxy groups both on the chain end and along the chain (about 2120 g of the siloxane copolymer contain 1 mol of allyloxy groups) are obtained.
EXAMPLE 8
About 21.2 g of the product from Example 7 (10 mmol of allyloxy groups) are mixed with 75 mg of 3-methyl-1-butyn-3-ol, 1.2 g of a copolymer containing methylhydrogensiloxane and trimethylsiloxane units having a viscosity of 20 mm 2 ×s -1 at 25° C. (20 mmol of Si-bonded hydrogen) and 240 mg of a solution of platinum tetrachloride in isopropanol which contains 1 percent of platinum, calculated as the element. The ready-to-use mixture containing inhibitor contains 100 ppm by weight of platinum, calculated as the element, and is processible at 25° C. in a closed vessel over 8 hours. The mixture is applied by means of a glass rod to coated kraft paper in a thickness of about 2 μm. During a residence time of 5 seconds in a circulating air oven at 80° C., the coating hardens to a non-tacky, rubbery covering which exhibits no "rub-off" and repels adhesive labels coated with acrylate adhesive. | Novel siloxane copolymers are described having an average of at least two alkenyloxy groups of the formula
--OCHR.sup.2 CR.sup.2 ═CH.sub.2,
in which R 2 represents hydrogen or a methyl radical.
These siloxane copolymers are prepared by reacting an organic compound (1) containing more than two aliphatic double bonds of the formula OCHR 2 CR 2 ═CH 2 where R 2 is the same as above, with an organopolysiloxane (2) having at least one Si-bonded hydrogen atom per molecule in the presence of a catalyst (3) which promotes addition of the Si-bonded hydrogen to an aliphatic double bond. The resultant siloxane copolymers may be crosslinked with organopolysiloxane containing Si-bonded hydrogen in the presence of hydrosilylation catalysts. | 8 |
SUMMARY OF THE INVENTION
The present invention relates to a clip which can be used for fastening a ring-like member to a sheet of flexible material such as fabric. The clip was developed primarily for fastening loops, poles and stakes onto a flexible web to provide a connector suitable for use in a tent made in accordance with my U.S. Pat. No. 3,986,519. However, as will become later apparent, the invention is one of broad applicability and has many other uses.
Heretofore, it was ordinarily necessary in fastening a member on the fabric to penetrate the material in some way such as by sewing a loop onto the canvas or by piercing the canvas and placing washer-like members on each side of the canvas on a support member. Fasteners which do not penetrate the fabric ordinarily provide a weak connection which is easy to pull apart.
In accordance with the present invention, an improved fastener is provided which does not require penetration of the fabric in any manner so that the canvas is not weakened. Strain on either the fabric or the fastener actually increases the gripping power.
An object of the present invention is to provide a fastener for canvas or the like wherein the strain is distributed over a large area of the canvas so that maximum strength is attained.
Another object of the present invention is to provide a clip which is easily inserted or removed without marring the fabric so that it may be moved from one location to another without leaving any evidence of its use behind.
Another object of the present invention is to provide a clip which can be applied to fabric without the use of tools and with only simple hand pressure.
Still a further object of the invention is to provide a clip which is adapted to carry a multiplicity of attachments.
Another object is to provide a fastener which is reuseable.
A still further object of the invention is to provide a clip which is simple to attach so that it can be put on by the user rather than the tent manufacturer, thus lowering production cost.
Still another object of the invention is to provide a clip which is adapted for securing two or more sheets of a flexible material together in a positive manner.
The clip of the present invention engages the fabric or other web between (a) mating flat surfaces on the two parts of the clip which are parallel to the surface of the web and (b) between mating collar surfaces at right angles thereto so that pulling on the female element will not cause the parts to become separated.
Other objects and features of the invention will be brought out in the balance of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a clip embodying the present invention.
FIG. 2 is a section on the line 2--2 of FIG. 1.
FIG. 3 is a perspective view, similar to FIG. 2, showing the motion of the parts during a first stage of assembling the clip to a piece of canvas.
FIG. 4 is a view similar to FIG. 3 showing the position of the parts just prior to final assembly.
FIG. 5 is a perspective view showing how the female element may be modified to hold a loop.
FIG. 6 is another embodiment of the female element showing an arch element having a pole holder and hold-down loop formed integrally therewith.
FIG. 7 is a perspective view of another embodiment of the female element showing a pole holder and loop formed on the element proper.
FIG. 8 is a sectional view showing how the clip of the present invention can be employed to lock a plurality of sheets together.
FIG. 9 is a perspective view showing a loop formed on the male element.
FIG. 10 is a perspective view showing a modified female element wherein it is not necessary to flex the female element in order to assemble the parts.
FIG. 11 is a perspective view of another embodiment of the invention.
FIG. 12 is an enlarged perspective view, partly in section, of the embodiment of FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to the drawings by reference characters, there is shown in FIGS. 1-4 a preferred embodiment of the invention which is provided with a loop element and is particularly adapted for use as a tent fastener in a tent constructed in accordance with my previously identified patent. In accordance with this embodiment of the invention, the male element generally designated 14 mates with a female element generally designated 16. In this embodiment of the invention, the female element must be somewhat flexible as is later explained in detail. The male element 14 has a flat plug portion 18 which terminates in cylindrical surface 20. A lip or rim 22 is formed at the outer edge of the cylindrical portion 20 and which has a flat surface 23. The female element 16 includes a collar 24 of a soft, flexible plastic and has a flat surface 25 which mates with flat surface 23 and its inner surface 27 mates with surface 20. In this embodiment of the invention, a loop 26 is formed integrally with the collar 24. The male element can also have a hook 28 formed thereon which is useful inside a tent for hanging articles or for fastening to another layer of fabric.
The method of assembly of the clip of the present invention is best seen with reference to FIGS. 3 and 4. The female element 16 is placed adjacent to a sheet, such as tent fabric 30. The ring element 24 is then compressed by finger pressure in the direction shown by arrows so that the round element 24 is distorted to an oval shape. The male element 14 is now passed through the oval shaped opening in the manner shown in FIG. 3, i.e. from the position shown in solid lines to the position shown in dot-dash lines. Now the element 14 is rotated one-quarter turn and pressure on the ring 24 released so that the parts are now in a position shown in FIG. 4. Now the male element 14 is pushed against the collar 24 so that the parts now assume the position shown in FIG. 2. The fabric 30 is engaged between the flat surfaces 23 and 25 and these surfaces are parallel to the plane of the main body of canvas 30 as well as between the surfaces 20 and 27 which are at right angles thereto, so either the female or male elements or the fabric can be pulled or twisted without disengaging the elements. It is thus apparent that the element has been snapped on to the fabric without puncturing the fabric in any manner and without seriously distorting it. Also since the gripping area is in the form of a large circle, the maximum strength of the fabric is utilized.
In FIG. 5 another embodiment of the female element is shown wherein the female element consists of a ring-like member 32 which is enlarged at one edge as at 34 with a hole 36 in the enlarged portion. This is useful as a tent hold-down since a rope 38 can be passed through the hole 36. The hole 36 could be made larger and elongated to provide a hand grip.
In FIG. 6 still another embodiment of the female element is shown wherein a ring 40 has an arch-shape loop 42 formed integrally therewith and wherein the element 42 has a hollow cylinder 44 and a loop 46 molded near the center. In assembling the element, the loop 42 has sufficient flexibility so that the parts 44 and 46 can be temporarily bent to one side for the insertion of the male element as is shown in phantom. The relationship of the parts is such that the entire female element, including the members 42, 44 and 46, can be easily molded from a single piece of plastic in a simple two piece mold. This is possible since 44 is parallel to the inside walls of 40 and the outer extremity of 46 lies within an imaginary extension of the inside walls of 40. This emnodiment serves both as a pole holder and a tie down at the edge of a tent and the pole holder can be bent to a desired angle.
In FIG. 7 still another embodiment of the female element is shown wherein a ring 48 has an extension 50 molded on one side thereof which has a hole 52 at the terminal end and a hollow cylinder 54 between the ring and the hole. Extension 50 preferably has a thin cross section at 51 so the pole holding the cylinder can be bent to a desired angle. This female element is particularly advantageous for use around the edges of a tent having arch-shaped poles since the terminal ends of the poles can be placed in the cylinder 54 and the hole 52 used for a tie-down rope. More than one cylinder can be formed on the extension 50, or more than one extension can be formed on the ring 48, so that two or more poles can be fastened. Slot 66 permits the element to be molded in a simple mold. The loop 68 has sufficient flexibility so that the parts can be assembled in the same manner as in FIGS. 3 and 4.
In some instances, one merely wishes to fasten two or more sheets together, in which case it is not necessary to provide either the male or female elements with loops or similar attachments. This utilization of the invention is shown in FIG. 8 wherein a first sheet of fabric 56 is fastened to a second sheet 58. The female element 60 and the male element 62 are merely used to hold the two sheets together. The two sheets are firmly attached yet can be detached at any time.
In some instances, it is desired to provide the male element with a large loop in which case the structure shown in FIG. 9 can be employed. Here the male element 64 is provided with a U-shaped member generally designated 68 which has straight side members 70 and 72 connected by the central arch 74.
In the embodiments of the invention heretofore described, at least the female element must be molded of a relatively soft, yieldable plastic such as polypropylene. Since the male element is not subjected to any distortion, it can be made of a hard plastic or even metal but preferably both parts of the fastener are molded from a yieldable plastic.
In FIGS. 10, 11 and 12 other embodiments of the invention is shown where neither element is subjected to any distortion so that both parts of the fastener can be made of a hard plastic or even metal.
In accordance with the embodiment of FIG. 10 the female element 76 is formed with two slots 78 which are directly opposed to each other. The male element 14 is as previously described and as can be seen in the drawings the rim 22 can be passed through slots 78 to assemble the fastener.
In accordance with the embodiment shown in FIGS. 11 and 12, the male element, generally designated 72, has a plug or cylinder portion 74 of generally rectangular configuration, and preferably has rounded ends 76. A rim 78 is provided which may have the same rectangular configuration. The female element, generally designated 80, has a slot 82 which is complementary to the plug 74. The member 80 may be provided with one or more holes 84 or other fastening means as heretofore described. In this embodiment of the invention, the female element is not distorted in any manner but the element 72 is merely turned sideways as is shown in phantom in FIG. 11 for insertion through the female element. After insertion, it is turned back so that the plug 74 lies in the slot 82 with one or more sheets of canvas 86 gripped between the male element 72 and the female element 80, holding a sheet of canvas 86 therebetween as is shown in FIG. 12.
Although certain specific embodiments of the invention have been shown, it is obvious that the invention is one of broad applicability and that the male and female elements may take different forms. Further, the elements have been described primarily for use as tent fasteners but it is obvious that they may be used as fasteners for any flexible sheet such as fabric, plastic, or even tough paper such as parchment paper. | A clip is provided which is adapted for fastening onto a flexible web such as a sheet of fabric. The clip is particularly adapted for fastening the fabric of a tent to supporting poles or stakes or for fastening webs together. | 8 |
This application is a divisional of co-pending application Ser. No. 494,589, filed Mar. 16, 1990 now U.S. Pat. No. 4,987,881 which is itself a divisional of application Ser. No. 366,262, filed June 12, 1989 (now U.S. Pat. No. 4,922,890) which is a continuation of application Ser. No. 06/428,542, filed Sept. 30, 1982, now abandoned. The benefit of the earlier filing dates of the foregoing applications under the provisions of 35 U.S.C. 120 is claimed.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to fuel burning furnaces and, more particularly, to a fuel burning furnace having improved characteristics of heat circulation, heat transfer, and, in general, energy efficiency.
2. Description of the Prior Art
Rising fuel costs and depleted fuel supplies have been a serious problem of recent times. These problems have initiated a nationwide concern for the energy efficiency of our fuel burning products. Among the products which use considerable amounts of fuel to operate are the furnaces which heat our homes and offices. While prior art furnaces do serve to provide heat to our living quarters they have done so in a relatively inefficient and wasteful manner.
Most prior fuel burning furnaces constitute box-type structures with several major openings including an inlet for air to be heated, an outlet for heated air, and an outlet for combustion gases. The furnaces additionally contain a heat exchanger for extracting heat from hot combustion gases and for containing spent fuel fumes, burners and a pilot to ignite and convert the fuel to energy, and a blower to force air to be heated through the heat exchanger and outwardly to areas to be heated.
Prior gas furnaces, although effective to produce heat, are not entirely satisfactory from an energy efficiency viewpoint. Much of the inefficiency inherent in furnaces of present design stems from the poor heat transfer characteristics of the heat exchangers. These heat exchangers generally provide a series of heat exchange enclosures, each one housing a burner, arranged in side-by-side relation. The burners are located near the bottom of the heat exchange enclosure and hot combustion gases are allowed to rise through the enclosure, thus heating the interior walls so that heat may be transferred to the exterior surfaces over which air to be heated is passed. A problem with these heat exchangers is that hot combustion gases pass essentially unrestricted up through the enclosure and out the flue vent, thus wasting large quantities of heat which could otherwise be extracted from the flue gases. Since much of the heat which could be utilized is lost through the flue vent and chimney, more fuel must be burned to provide the requisite heating air.
Another problem not adequately addressed by prior furnaces relates to providing the burners with sufficient fresh air to complete combustion of the fuel being burnt. During the winter months, when the furnaces are used the most, it is a standard practice to keep the house as air-tight as possible to prevent warm air from escaping and to provide a good insulating effect. This creates a problem, however, in that an adequate supply of fresh air is not allowed to enter the house. Fresh air is necessary to complete the combustion process and to extract all the potential energy provided by the combustible fuel. If complete combustion does not occur, a significant amount of the combustion fuel will be vented along with the hot combustion gases. As a result of this incomplete burning of fuel, additional fuel must be burned to compensate for the inefficiency of the furnace and provide the requisite heat necessary to maintain proper temperature levels.
Recent proposals have provided electric ignition systems to ignite the fuel at the burners when the temperature drops below a predetermined level. It has been suggested that electric ignition systems are more energy efficient than the gas pilot systems presently utilized, as they are not continually burning and are only activated on command from a remote temperature sensor. These electrical ignition systems have suffered from several drawbacks. In spite of the fact that they are not continually operating, as is the case with the standard gas pilots, their overall efficiency is very poor, on the order of about 30%. Another problem which occurs from the use of electric ignition is that each time at the beginning of combustion cycle when the furnace burners have come on, water vapor is permitted to condense on surfaces of the heat exchanger because the electric ignition does not dry it off. This water tends to corrode the heat exchangers and shorten their life. Even more importantly, corrosion reduces the heat transfer characteristics of the heat exchanger, since a layer of rust develops on the outer surfaces on the heat exchange enclosures.
Yet another problem which has not been adequately addressed relates to the detection of problems of heat flow and air circulation in the furnace. Prior furnaces provide no means of checking the efficiency or operation of the furnace, thus making it very difficult to detect and correct problems at an early stage. As problems with air circulation and heat transfer develop, the furnace must burn more fuel in order to maintain adequate room temperatures. For instance, if the heat transfer characteristics of the heat exchanger were to fall to 50% of their normal operating values, the furnace would burn twice as much fuel to compensate for this problem with no indication that a problem even existed, and what is worse, no way to even check. Thus, problems may go undetected for long periods of time with nothing being done to correct them.
SUMMARY OF THE INVENTION
In accordance with the foregoing considerations, the present invention provides a new and improved fuel burning furnace having a number of energy efficient features. A significant feature of the invention relates to the heat exchanger and how heat is transferred, circulated and discharged. In order to improve the heat transfer characteristics of the heat exchanger various provisions are made for urging the hot combustion gases toward the interior surfaces of the heat exchanger. Other provisions are made to contain the hot combustion gases for longer periods of time in order to extract as much of the available heat as possible. In one embodiment, a longitudinally-extending baffle plate extends through the center of the heat exchanger at a location above the burner. Where this feature is utilized, hot combustion gases are diverted to either side of the baffle plate and toward the interior surfaces of the heat exchanger, thus bringing the hot combustion gases in closer contact with the interior surfaces and improving the heat transfer characteristics of the heat exchanger. Additionally, a V-shaped baffle is provided near the top of the enclosure substantially parallel to the burners so that as the hot combustion gases rise toward the flue vent port, the hot combustion gases again are diverted toward the interior portions of the enclosure before exiting the heat exchanger. The baffles also extract heat from the hot combustion gases, thus improving the heat transfer characteristics of the furnace.
In order to more effectively utilize the combustion gases at their hottest temperature, diverters are provided directly above the burners to direct the hot combustion gases toward the interior surfaces of the enclosure shortly after ignition. Each diverter is generally A-shaped, as viewed from the end, and is located directly above one of the burners and extends along its length. The sloping sides of the baffle have a plurality of apertures of various sizes and shapes through which the hot combustion gases are forced, thus directing the hot combustion gases toward nearly the entire interior surfaces of the heat exchange enclosure. This is a significant improvement over prior heat exchangers which allow the hot combustion gases to pass from the burners to the flue vent essentially unrestricted. By utilizing the just-ignited gases more effectively, the heat transfer characteristics of the heat exchanger can be greatly improved.
In another embodiment of the present invention, the heat transfer characteristics of the heat exchanger are improved by providing adjacent sidewalls of the enclosure with inwardly extending notches which form restrictions in the passageway of the hot combustion gases. In preferred practice, the inwardly extending notches are alternated with outwardly extending portions of the side walls, thus providing a heat exchanger with very irregular surfaces. By providing restrictions to the passage of the hot combustion gases, the hot combustion gases are forced into direct contact with the side walls at the points of restriction, thus improving the heat transfer characteristics of the enclosure. In addition, the outwardly-extending irregular surfaces of the heat exchange enclosure create a turbulent action of the hot combustion gases as they pass from the burners toward the flue vent port. The turbulent action of the hot combustion gases as they pass through the heat exchanger is important as it increases the circulating effect of the hot combustion gases which, in turn, increases convective heat transfer.
In still another embodiment of the present invention, the heat exchangers are provided with interior baffle plates which form weaving passageways from the burner toward the flue vent. Where this embodiment is utilized, the hot combustion gases are forced to remain in the heat exchanger for longer periods of time, thus allowing them to dissipate their heat to the interior surfaces of the heat exchange enclosure.
In another embodiment of the heat exchanger pairs of heat exchange enclosures are provided and are joined at their centers so that hot combustion gases may pass between them. Each of the enclosures houses a separate burner. When it is necessary for the furnace to produce heat, one of the burners initially is ignited and the hot combustion gases from this burner are shared between both enclosures with the second burner remaining unignited. This feature enables much more heat to be extracted from the hot combustion gases from the fuel burner than otherwise would be possible. A time delay is provided for the second burner such that it will be ignited a fixed time after the first burner is ignited. If adequate heating is not performed during the time delay, the second burner will be ignited. In preferred practice, a plurality of heat exchanger pairs are provided, with one burner being ignited directly on command and the second burner being delayed for a fixed period of time.
Another alternative embodiment of a heat exchanger includes a plurality of heat exchange enclosures contained in an external housing. Hot flue gases, are circulated over the outer surfaces of the sidewalls of the enclosures and are confined by the housing. Air to be warmed is circulated within the enclosures and is confined by the sidewalls. An advantage of this embodiment is that the number of heat exchange enclosures can be greater than the number of burners, therefore, the effective surface area which is in heat exchange relation with the hot flue gases is increased without increasing the number of burners necessary to operate the system.
Another feature of the present invention lies in the provision of a heat exchanger which is provided with a return air diverter positioned between adjacent heat exchange enclosures. This feature allows the air to be heated to be urged toward the exterior surfaces of the adjacent heat exchange enclosures, thereby placing the air to be warmed in closer heat exchange relation with the exterior surfaces of the enclosures. The diverter is made of steel, the same as that of the heat exchangers, and is mounted on the same fabricated weldment structure. The diverter also serves as an extrusion of the heat exchangers and helps to extract more heat from the hot combustion gases.
In another embodiment of the heat exchanger, heat exchange enclosures are joined near their lower sections so that the burners may be inserted transversely. Accordingly, a single burner may pass through several heat exchange enclosures. In this embodiment, the number of heat exchange enclosures may be greater than the number of burners, thus effectively enlarging the surface area in which heat transfer may be carried out. For instance, four burners may be placed in heat exchange relation with six different heat exchange enclosures, each burner serving to introduce heat to different portions of each enclosure.
In order to minimize heat loss through the flue vent and improve combustion efficiency of the burners, a combustion air preheating system is provided. The air preheating system includes a passageway which extends through the interior of the heat exchange enclosure, the passageway being in heat exchange relation with the hot discharged combustion gases. The passageway is communicated with a source of fresh air, preferably from the exterior of the house. The fresh air is brought in through the flue vent into the heat exchange enclosure, thereby preheating the air. The preheated air then is introduced near the burner to assist in the combustion process. This is an important feature in that it provides sufficient fresh air to complete the combustion process so that unnecessary fuel is not burned, and further reduces the burden of heating the air by taking advantage of the hot flue gases as they are vented.
Still another feature of the present invention lies in the provision of a fuel burning furnace which indicates decreasing efficiency at an early stage. A temperature sensor is provided within the heat exchanger assembly to measure temperature of the circulating air before it exits the heat exchanger assembly. Problems in heat transfer can be determined by periodically noting the temperature of the circulating air. Additionally, a manometer is provided which extends into the furnace enclosure to indicate differential pressure between the inside and outside furnace enclosure thereby indicating problems in circulation. A by-pass line is additionally provided on the fuel line so that in case of power failure, fuel still may be provided to the burners.
To compensate for loss of tension in the drive belt of a blower motor, a spring-loaded idler pulley is provided. The pulley is continually urged against the belt to keep tension on it. As the belt wears, and normally would begin to slip, the spring-loaded idler pulley keeps tension on the belt and prevents slippage.
In addition, the drive pulley includes two halves which are connected by biasing springs. The halves form a V-shaped groove in which the drive belt rides. As the ambient temperature increases the springs expand and urge the pulley halves closer together. This causes the drive belt to ride higher in the groove, thus effectively increasing the diameter of the pulley and causing the fan to turn faster. Thus, blower motor speed is controlled in response to temperature.
Another significant feature of the invention is the addition of a humidity control device which works to keep a proper amount of moisture in the air at all times. In winter when the air is very dry, the system works to add water vapors to the air as it is passed through the furnace. This is accomplished by installing an evaporated in the furnace plenum to which water is supplied. Porous, mineral wool plates are installed on the sides of the evaporator, both of these plates resting in a trough which is filled with the water at a certain height. The plates will absorb water by wick action and increase the relative humidity of the circulating air and at the same time, heat will be extracted from the flue gases as they are passing out of the furnace.
In summertime when the air is very moist, the system removes water vapors from the air. This is done by passing city water supply or well or river water through coils over which warm water-laden air is passed, causing condensation on the coils and thus extracting unwanted water from the atmosphere. These and other features and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic, perspective view of a fuel burning furnace embodying a preferred practice of the present invention;
FIGS. 1B, 1C, 1D, and 1E are schematic, cross-sectional views of air preheating systems included as part of the invention;
FIG. 2 is a cross-sectional view of two of the enclosures of a heat exchanger, and inside and outside diverting baffles;
FIG. 3 is a perspective view of the heat exchanger showing a preheating system;
FIG. 4 is a sectional view of one embodiment of a heat exchange enclosure;
FIG. 5 is a perspective view of another embodiment of a heat exchanger showing burners extending transversely through each heat exchange enclosure;
FIG. 6 is a sectional view of a portion of FIG. 5 as seen from a plane indicated by line 6--6;
FIGS. 7 and 8 are cross-sectional views of other embodiments of a heat exchanger;
FIG. 7A is a perspective view of a portion of a gas diverter usable with a heat exchanger according to the invention;
FIG. 9 is a perspective view of a clip attached to adjacent sides of a heat exchange enclosure;
FIG. 10 is a side elevational view of one embodiment of a heat exchanger according to the invention;
FIG. 11 is a cross-sectional view as seen along a plane indicated by line 11--11 in FIG. 10 of another embodiment of the heat exchanger;
FIGS. 12, 13 and 14 are cross-sectional views of interior baffle plates for containing hot flue gases in a heat exchange enclosure prior to venting;
FIG. 15 is a side elevational view of a blower motor system showing a V-belt tensioner; and,
FIG. 16 is a cross-sectional view of a spring-biased pulley for adjusting motor speed in response to temperature.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a fuel burning furnace embodying the preferred practice of the present invention is indicated generally by the numeral 10. The fuel burning furnace 10 is shown as having burners 12 and a heat exchanger indicated generally by the numeral 14. The burners 12 are substantially enclosed by the heat exchanger 14 and serve to produce hot combustion gases. In preferred practice the burners are ignited by a standby continuous pilot light (not shown) as is well known.
In normal operation, the hot combustion gases are contained by an interior portion of the heat exchanger 14, as will be described. Other exterior portions of the heat exchanger 14 are located in heat exchange relationship with return air to be heated and communicated to the areas to be heated. The furnace 10 is enclosed by a metal housing indicated generally by the numeral 16. In preferred operation, return air is drawn through a filter compartment 18 of the housing 16 and circulated past the outer portions of the heat exchanger 14.
Hot flue gases produced by the burners 12 are vented through exhaust ducts 20 formed in upper portions of the heat exchanger 14. The ducts 20 discharge into a manifold (not shown). The manifold is connected to a flue vent pipe 24 which directs the flow of flue gas to the outside atmosphere.
Referring to FIG. 3, the heat exchanger 14 includes a plurality of heat exchange enclosures 40. The heat exchange enclosures 40 are of generally rectangular shape, as viewed from the side, and have a substantially elliptical cross section, as viewed from the front, with the major axis of the ellipse oriented vertically. The front surfaces of the enclosures 40 are formed by a common face plate 42. A lower portion of the face plate 42 is provided with openings 94 for accommodating the burners 12 which extend therethrough into the enclosures 40. Upper portions of the face plate 42 additionally include the exhaust ducts 20 for venting combustion gases from the enclosures 40. A temperature gauge 46 is provided to sense the temperature of the air being heated within the heat exchanger 14. The temperature gauge 46 enables decreases in the temperature of the air being passed through the exchanger 14 to be noted. Temperature decreases will indicate heat transfer problems occurring within the heat exchanger 14.
Referring to FIG. 4, each heat exchange enclosure 40 includes a pair of adjacent sidewalls indicated generally by the numerals 48. Interior portions of the walls 48 are in heat exchange relation with the hot flue gases as the gases rise from the burner 12. Exterior portions of the walls 48 are in heat exchange relation with air to be heated. The sidewalls 48 include inwardly extending notches 50. The inwardly extending notches 50 on adjacent sidewalls 48 form restrictions at selective locations along the length of the heat exchange enclosure 40 in order to restrict the flow of hot flue gases and bring them into close contact with the inner portions of the walls 48, thus effecting improved heat transfer. The walls 48 additionally are provided with outwardly extending notches 52 which alternate with the inwardly extending notches 50. The inwardly and outwardly extending notches 50, 52 cause the rising hot flue gases to pass through the heat exchange enclosure 40 in a turbulent manner, thereby increasing conductive and convective heat transfer. The height of the heat exchange enclosure 40 is nearly the same as the height of a conventional heat exchanger, but the heat exchange enclosure 40 has more surface area. Thus having a large surface area, the heat exchange enclosure 40 will extract much more heat from the hot combustion gases. Also, because there is no straight path for combustion gases to vent from the system, it will take much longer for exhaust gases to be exhausted, which also is an advantage.
Although the sidewalls 48 are shown in FIG. 4 as being irregular, this is not absolutely necessary. Referring to FIG. 2, heat exchange enclosures 54 are shown as having a single inwardly extending portion 56 intermediate the top and the bottom portion of each sidewall 58. Where this configuration is utilized, a baffle plate 60 extends longitudinally through the center of the enclosure 54. The baffle 60 is located intermediate the sidewalls 58 and serves to divert hot flue gases from the burners 12 toward the inner portions of the sidewalls 56 to improve the heat transfer characteristics of the heat exchange enclosure 54. Near the top of the baffle 60, a V-shaped baffle 62 is provided to urge hot combustion gases toward outwardly extending portions 64 near the top of the sidewalls 58. The baffle 62 restricts the free flow of hot flue gases due to reduction of the cross-sectional opening.
A generally elliptical baffle 66 (in cross-section) additionally is provided between adjacent heat exchange enclosures 54 as shown in FIG. 2. As return air to be warmed circulates through the heat exchange enclosures 54, it is urged toward the outer surfaces of adjacent sidewalls 58. The use of baffles 60, 62, and 66 serves to keep the hot flue gases and return air to be heated in closer heat exchange relation and thus more effectively heat the surrounding air.
Referring to FIG. 9, a resilient clip 70 is provided to engage adjacent sidewalls 48 of the heat exchange enclosures 40. The clip 70 serves to keep the sidewalls 48 from expanding and contracting relative to a fixed support structure and thereby creating a popping sound. By reducing the movement of the sidewalls 48 caused by the expansion and contraction under heated and subsequent cooling conditions, the life of the heat exchange enclosures 40 can be significantly prolonged. In addition, the clip 70 gives more mass to the heat exchanger 14, thus enabling it to extract more heat from the hot combustion gases and at the same time enabling it to stay hot for a longer period of time.
Referring to FIG. 12, a method for retaining hot flue gases in the enclosure 40 and extracting more heat is illustrated. In this embodiment of the heat exchange enclosure 40, a plurality of vertically oriented interior walls 84 are provided to form various passageways 86 through the heat exchange enclosure 40. The walls 84 serve to retain the hot flue gases for an extended period of time and allow more of the useful heat to be transferred to the interior surfaces of the sidewalls 48. The interior walls 84 can be arranged to define a variety of passageways 86. Interior walls 84A and 84B define alternate passageways 86A and 86B as illustrated in FIGS. 13 and 14, respectively.
Referring to FIG. 5, another embodiment of the heat exchanger is shown and is indicated generally by the numeral 120. In this embodiment, a plurality of heat exchange enclosures 130 are provided with openings 127 in their lower side portions for accomodating the burners 12 which are placed therethrough. In this embodiment, lower portions of the heat exchange enclosures 130 are connected at the openings 127 so as to enclose substantially all of the burners 12. Each burner 12 extends through each of the heat exchange enclosures 130 so that each heat exchange enclosure 130 contains a portion of the burner 12. In this embodiment, the burners 12 extend through the sides of each of the heat exchange enclosures 130, rather than through the front as previously described for the heat exchanger 14. By arranging the burners 12 as described above, the number of heat exchange enclosures 130 can be greater than the number of burners 12, thus increasing the heat exchange surface without increasing the number of burners 12.
Referring to FIGS. 5 and 6, each heat exchange enclosure 130 is connected by a common face plate 122. The face plate 122 is shown as having an upper section 121 and a lower section 123. The upper section 121 has a reversely bent portion 124 near its lower edge. The lower section 123 has a reversely bent portion 125 near its upper edge. The portions 124, 125 are placed together with an intermediate seal 126 of silicone rubber or like material to form the face plate 122. The portions 124, 125 are relatively movable so as to prevent premature heat exchanger failure due to repeated expansion and contraction, but they nevertheless provide a good thermal seal.
Where the heat exchanger 120 is used, each heat exchange enclosure 130 is provided near its upper end with V-shaped baffles 142 extending from front to back. A plurality of V-shaped baffles 145 are oriented parallel with the burners 12 at the upper end of the heat exchange enclosures 130. Each burner 12 is provided with a diverter 147 which extends parallel to the burner through the heat exchange enclosures 130. Details of the diverter 147 are described subsequently with respect to another heat exchanger embodiment.
Referring to FIG. 7, another embodiment of the heat exchanger 14 is indicated generally by the numeral 220. In this embodiment, heat exchange enclosures 230 include walls 234 which curve outwardly and upwardly in order to increase the surface area of the heat exchange enclosures 230 without increasing the overall height of the heat exchanger 220. This arrangement also provides a restriction to the path of the hot combustion gases which are ready to be vented. By increasing the length of the path which the hot combustion gases will take, the hot combustion gases tend to sweep along the inside walls of the heat exchanger 220 and thereby increase the heat transfer.
A gas diverter 147 in the form of an inverted V is provided and extends through the heat exchange enclosure 230 above the burner 12. Referring to FIG. 7A, the diverter 147 is shown as having a solid top portion 148 and sidewalls 150 with a plurality variety of apertures 152. The apertures 152 are arranged so as to direct the flow of the hot flue gases toward the inner surfaces of the walls 234 of the heat exchange enclosure 230. By directing the hot flue gases toward a location near the walls 234, the hot combustion gases are brought into heat exchange relation with the interior portion of the walls 234 intermediately after combustion. Although the diverter 147 is shown as being used with the heat exchange enclosure 230, it will be appreciated that the diverter 147 also can be used with any of the embodiments of the heat exchange enclosure.
Referring to FIG. 8, an alternative embodiment of a heat exchanger is indicated generally by the numeral 320. In this embodiment, heat exchange enclosures 330 are contained in an external housing 339. Hot flue gases, indicated by the arrows 338, are circulated over the outer surfaces of the sidewalls 334 of the enclosures 330 and are confined by the housing 339. Air to be warmed is circulated within the enclosures 330 and is confined by the sidewalls 334. Where this embodiment is utilized, the housing 339 contains the hot flue gases released by the burners 12 and allows them to be vented. A significant advantage of the heat exchanger 320 is that the number of heat exchange enclosures 330 is greater than the number of burners 12, therefore, the effective surface area which is in heat exchange relation with the hot flue gases is increased without increasing the number of burners necessary to operate the system.
Referring to FIGS. 10 and 11, another embodiment of the heat exchanger is indicated by the numeral 420. In this embodiment, a pair of heat exchange enclosures 430, 432 are placed in side-by-side relation. Adjacent sides of the enclosure pairs 430, 432 are joined by laterally extending portions 434 such that a passageway 436 is formed between the enclosures 430 and 432. Each of the enclosures 430, 432 houses a burner 12. The burners 12 extend through the lower portions of the enclosures 430, 432. Where this configuration is utilized, hot flue gases are free to pass between the enclosures 430, 432 through the passageway 436. In preferred operation of this embodiment of the present invention, the burners 12 in the enclosures 430 are ignited when the temperature of the air to be warmed falls below a preset level. The burners 12 in the enclosures 432, however, is not ignited until after a fixed period of time has elapsed after the burners 12 in the enclosures 430 has been ignited. After the first-ignited burners 12 are initially ignited, the hot flue gases produced therefrom are shared by the enclosures 430, 432, thus increasing the surface area available to the air to be warmed as it passes over the exterior portions of the heat exchange enclosures 430, 432. If the heat produced by the first-ignited burners 12 is not sufficient to bring the areas to be heated up to the preset temperature, the second-ignited burners 12 are ignited to provide additional heat. This delayed heating is a significant advantage over presently existing heat exchange units since all burners do not have to be ignited to make small corrections in room temperature fluctuations. In addition, prior to the time the second-ignited burners 12 are ignited, the hot combustion gases produced by first-ignited burners 12 have more surface area available in which to dissipate their heat.
Referring to FIG. 1, the burners 12 are supplied with combustible fuel by a supply line 160. The supply line 160 is provided with a motorized valve 161 which regulates the flow of fuel through the burners 12 in response to temperature changes. The valve 161 is energized by a pair of lead lines L1, L2 which are connected to a 110 volt source of electricity. A thermocouple 162 is disposed within the vent pipe 24 and is connected to the valve 161 by a lead line 163. Although the thermocouple 162 can be located in a number of different positions, it is expected that the thermocouple 162 will be placed at the location where flue gases are vented out into the chimney. The thermocouple 162 provides a control signal to the valve 161 so as to control the flow of gas to the burners 12 in a manner directly proportional to the temperature of the flue gases. A temperature indicator 164 is disposed in the line 163 so as to provide a visual indication of the temperature of the flue gases being discharged from the furnace 10.
The fuel line 160 is also provided with a manually operated valve 165 and a bypass line 166. The bypass line 166 permits the passage of fuel through the burners 12 in the event that a power failure occurs, in which case the flow of fuel normally is shut off. A normally closed solonoid-operated valve 167 is provided for the bypass line 166. In case of a power failure, the valve 167 is opened and fuel will be permitted to flow through the bypass line 166, if desired. A hand-operated valve 168 is provided in the bypass line 166 so that fuel will flow through the bypass line 166 only when desired. In preferred operation, the valve 165 in the main supply line 160 is closed at the same time that the valve 168 is opened.
The furnace 10 is provided with a number of features for monotoring its performance and thus detecting problems at an early stage. To keep track of the amount of fuel being used, a flow meter 169 is provided in the line 160. If desired, the thermometer 46 or the thermometer 164, or both, can be connected to an alarm bell (not shown) so as to provide an aural indication if the temperatures within the furnace 10 exceed predetermined limits. The furnace 10 additionally is provided with a clear glass or plastic manometer 170 for detecting pressure differentials between the exterior and the interior of the filter compartment 18. The manometer 170 essentially is U-shaped and is filled with a heavy fluid 172, such as red draft gauge oil. Under normal operating conditions, the level of the fluid 172 on the atmosphere side of the U-shaped fixture would be higher than on the other side because the filter compartment 18 is under pressure. As pressure inside the filter compartment 18 decreases due to insufficient airflow, the fluid level on either side of the U-shaped manometer 170 would tend to be the same, thus indicating insufficient airflow.
Air is drawn into the compartment 18 and is forced through the heat exchanger 14 by means of a belt-driven, squirrel-cage type fan 180 as shown in FIG. 1. The squirrel-cage fan 180 is connected to a pulley 181 shown in FIG. 15. The pulley 181 is rotated by a V-shaped drive belt 182 connected to a motor-operated pulley 183. Referring to FIG. 16, the pulley 183 is mounted to an axle 188 extending outwardly of a motor 192. The pulley 183 includes two identical halves 184 which fit together on the axle 188 and form a grove into which the V-belt 182 rides. Springs 185 are provided between the pulley halves 184 and collars 186. Another spring 187 is located between the two halves 184 encircling the axle 188. The spring 187 has a lower coefficient of expansion than each of the springs 185 so that, as the temperature inside the housing 16 increases, the springs 185 expand and urge the pulley halves 184 closer together. In turn, the V-belt 182 is caused to ride up higher on the pulley 183 and effectively increase the diameter of the pulley 183. By increasing the diameter of the pulley 183, the V-belt 182 rotates faster and increases the speed of the squirrel-cage fan 180. Thus, the speed of the fan 180 increases at a rate directly proportional to the temperature inside the housing 16.
The motor 192 is mounted on spring-loaded brackets 193 and mounts 194, and can be adjusted to compensate for any misalignment of the pulleys 181, 183. As the V-belt 182 becomes less tense due to stretching it will begin to slip on the pulleys 181, 183. To compensate for this lack of tension and possible slippage of the belt 182, an idler pulley 190 continually is urged against the belt 182 by a spring 191. As the belt 182 begins to lose tension, the spring 191 continually urges the idler pulley 190 against the belt, thus keeping the belt 182 under proper tension.
Referring to FIG. 1, the furnace 10 is provided with a humidity control device indicated generally by the numeral 200. The humidity control device 200 serves to increase the water vapor content of ambient air when the air is dry, and serves to decrease the water vapor content of the air when the air is moist. The humidity control device 200 includes a generally A-shaped frame 201, a trough 202, removable side panels 204, a water inlet 205 and a float valve 207. The device 200 also includes a drain pipe 208 for conveying water from the trough 202 to the floor or other suitable location. A small detachable extension pipe 210 is provided for the pipe 208 where it opens into the trough 202. The extension pipe 210 enables water to be maintained in the trough 202 at a predetermined level. When it is desired to prevent a build up of water in the trough 202, the extension pipe 210 can be removed.
The humidity control device 200 sits atop the furnace 10 on an L-shaped channel 203 located above the furnace plenum. The A-shaped frame 201 is located above the trough 202 and supports the removable side panels 204. When it is desired to humidify the air (as in the wintertime), water is supplied to the trough 202 via the inlet 205. Water is permitted to flow upon operation of a shutoff valve 206 in the inlet line 205. The water is kept at a predetermined level by the float valve 207 and the pipe 210. The side panels 204 generally are of a water-absorbing, porous material and are placed in contact with the water in the trough 202 so that the side panels 204 remain saturated. As air passes through the side panels 204, the water contained therein will evaporate, thus causing an increase in the water vapor content of the ambient air.
The humidity control device 200 also can be used as a dehumidifier when the side panels 204 are removed and condensing coils 214 are exposed. When used as a dehumidifier, the device 200 should be used with the extension pipe 210 removed. The condensing coils 214 are placed in series with the household plumbing 218 (connections not shown), and supplied with bypass valves 216 so that when the humidity control device 200 is used as a humidifier, the condensing coils 214 can be bypassed. If desired, a flow switch (not shown) can be installed in the pipes 205, 218. The flow switch can be connected to the blower motor 192 such that the blower motor 192 automatically will be activated whenever the humidity control device 200 is being used either for humidification or dehumidification. As water-laden air passes over the condensing coils 214 (which are maintained at a lower temperature than the surrounding air due to cool water being passed through them via the household plumbing), water vapor will begin to condense on the coils 214 and will be deposited in the trough 202. The humidity control device 200 can be used in conjunction with the furnace 10 or it can be used independently to humidify and dehumidify circulated air.
Referring once again to FIG. 1, a lightweight blower fan 240 is illustrated schematically. The fan 240 is intended for use in case an electrical power failure occurs or in case the main power motor 180 experiences an unexpected failure. In these circumstances, the fan 180 can be removed from the furnace 10, and the alternate fan 240 installed in its place. The fan 240 is provided with a rechargable battery 242 of either 6 or 12 volts.
The invention also provides a system for preheating combustion air for the burners 12. Referring generally to FIGS. 1B, 1C, 1D, and 1E, the air preheating system provides that preheated air will be drawn into the furnace 10 only when burners 12 are in operation and calling for air in order to complete combustion. Preheated air for combustion can provide many beneficial effects which are missing from unpreheated combustion air. More specifically, preheated air can increase the flame intensity, improve thermal and combustion efficiency, decrease the consumption of fuel, require less time to obtain desired furnace temperature, cool the flue gas temperature, and minimize the possibility of combustion product leakage. At the same time, preheating the combustion air can give more surface are to the heat exchangers so as to provide more heat transfer to circulating heated air.
Referring particularly to FIG. 1B, a preheating/gasdischarge system 500 is included as part of the furnace 10. The system 500 includes a jacket 502 disposed about the vent pipe 24. The vent pipe 24 includes a so-called barometric damper 504. The barometric damper 504 applies atmospheric pressure to the flue gas vent system 500. The damper 504 automatically will control air pressure within the furnace 10 so as to prevent unnecessary pressure being applied to the gas burners 12 downwardly through the vent pipe 24. The jacket 502 is in communication with a manifold 506 which, in turn, is in communication with the burners 12. As will be apparent from an examination of FIG. 1B, combustion air for the furnace 10 will be directed downwardly intermediate the vent pipe 24 and the jacket 502. As a consequence, combustion air will be heated from flue gases passing outwardly through the pipe 24. Thereafter, the preheated combustion air can be directed through the manifold 506 to the burners 12.
An alternative embodiment of the air preheating/gas discharge system 500 is illustrated in FIG. 1C. A jacket 512 is disposed about the vent pipe 24. A barometric damper 514 is included as part of the vent pipe 24. A manifold 516 directs preheated combustion air from the jacket 512 to the burners 12. In this embodiment of the invention, a compressor 518 is provided to establish a source of compressed air. A pipe 520 extending outwardly of the compressor 518 is in communication with the vent pipe 24. A drain pipe 522 having a trap 524 is provided in a lower portion of the pipe 24 so that, as water vapor contained in the heated flue gases condenses and the pipe 24, either is allowed to drain to the floor or other appropriate location. The trap 524 is provided in order to prevent flue gases to be vented through the pipe 522.
In operation, the embodiment of FIG. 1C provides preheated combustion air for the burners 12 much as was done with the embodiment of FIG. 1B. In addition, use of the compressor 518 will assure that flue gases will be vented outwardly of the pipe 24. The compressor 518 will be used only when there is "negative pressure" tending to cause a flow of air backwardly through the vent pipe 24 into the furnace 10.
Yet another alternative embodiment of the invention is shown in FIG. 1D. In this embodiment of the invention, a somewhat more effective air preheating system is provided. The vent pipe 24 is relatively large. At a location outside the structure in which the furnace 10 is located, an air intake pipe 532 extends through an opening in the pipe 24. The intake pipe 532 is concentrically disposed within the vent pipe 24. A barometric damper 534 is included as part of the vent pipe 24. The intake pipe 532 is in communication with a jacket 536 which surrounds a major portion of the heat exchange enclosures 40. The heat exchange enclosures 40 are provided with a plurality of openings 538 in their bottom surfaces. By this construction, intake air is preheated very effectively not only during its passage through the intake pipe 532, but also during its passage around the heat exchange enclosures 40. The openings 538 enable preheated combustion air to be discharged uniformly at a location immediately adjacent to the burners 12.
The embodiment illustrated in FIG. 1E is a variation of the invention illustrated in FIG. 1D. In this embodiment of the invention, an air intake pipe 542 is disposed concentrically within the vent pipe 24. No barometric damper is provided in this embodiment of the invention. The intake pipe 542 is in communication with a jacket 544 which substantially surrounds the heat exchangers enclosures 40. A plurality of openings 546 in the lower surface of the heat exchange enclosures 40 permits combustion air to be directed into the heat exchange enclosures 40 at a location adjacent the burners 12.
In order to control the flow of air through the furnace 10, the compressor 548 is provided. A first line 550 is in communication with the intake pipe 542. The upper end of the intake pipe 542 is closed by a cover 552 through which the line 550 extends. This construction enables air under pressure to be forced into the intake pipe 542. A second line 554 extends outwardly of the compressor 548. The second line 554 is in communication with the vent pipe 24. The foregoing construction enables compressed, preheated combustion air to be supplied to the burners 12 while, at the same time, enabling heated combustion gases to be forced outwardly through the flue vent 24.
It will be appreciated from the foregoing description that the efficiency of the furnace 10 should be sufficiently great that the need for draft hoods and automatic flue dampers should be eliminated. Draft hoods, as are commonly in use with conventional furnaces, prevent a large quantity of room air to be mixed with hot combustion gases prior to discharge of the gases from the furnace. Although a draft hood is very inefficient for reducing the temperature of combustion gases, it is necessary with the design of conventional furnaces.
Automatic flue dampers, as is well-known, consist of a movable valve of some type placed in the flue vent of a conventional furnace. When combustion is occurring, the damper is moved to a position that will permit flue gases to be vented to the atmosphere. When combustion is not occurring, the damper will be closed in order to retain heated air within the structure. Unfortunately, not only are automatic dampers an additional expense item, they also have the inherent problem of potential failure. Obviously, if the damper fails to operate, either heated air will be permitted to escape from the structure, or combustion will occur with the flue vent blocked.
Because the furnace 10 according to the invention, in its preferred embodiment, draws combustion air entirely from outside the structure, there is no need for an automatic flue damper. That is, heated air within the structure cannot escape through the flue vent simply because there is no access to the flue vent other than through the furnace and, in turn, this air must come entirely from outside the structure. The need for a draft hood also is eliminated because the heat exchange enclosures are very efficient and because the intake air for combustion is preheated. Because the intake air is preheated by being in indirect contact with the flue gases, the temperature of flue gases is reduced to the point where it is not necessary to dilute the flue gases prior to their discharge. Accordingly, the need for a draft hood is totally eliminated.
Although the invention has been described in its preferred form with a certain degree of particularity, it will be understood that the present disclosure of the preferred form has been made only by way of example and numerous changes in the details of construction and combination and arrangement of parts may be resorted to without departing from the true spirit and scope of the invention as hereinafter claimed. It is intended that the patent shall cover, by suitable expression in the appended claims, whatever features of patentable novelty exist in the invention disclosed. | A fuel burning furnace includes a number of energy efficient features. The furnace includes a heat exchanger in which combustion air is preheated by hot discharge gases. Diverters are provided in the heat exchanger to continually urge hot combustion gases toward the interior portions of the heat exchanger to improve its heat transfer characteristics. The furnace incorporates a number of features to determine malfunction and indicate inefficient operation. A humidification control system for the humidification or dehumidification of circulated air also is provided. The furnace also includes a blower motor system which compensates for loss of tension in driving belts and makes correction for blower speed in response to temperature variations. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to the field of re-liquefaction of boil-off gases from liquid natural gas (LNG). More specifically, the invention relates to a method and an apparatus for pre-heating LNG boil-off gas (BOG) stream flowing from a reservoir in a reliquefaction system, prior to compression, and a method and an apparatus for cooling an LNG boil-off gas (BOG) stream in a reliquefaction plant.
Background
[0002] A new generation of LNG vessels was established in association with the introduction of LNG reliquefaction systems (LNG RS). Prior to this, basically all LNG vessels were driven by steam turbines fuelled by boil off gases (BOG) evaporating from the cargo during transportation. In periods when the total amount of BOG was insufficient to cover the entire power demand, additional LNG had to be fed to the boilers through forced vaporizers.
Brief Description of the Prior Art
[0003] The new LNG RS opened the possibility to collect, cool down and reliquefy all BOG and hence preserve the total cargo volume throughout the laden and ballast voyages. Conventional slow speed diesel engines, with high efficiencies compared to the steam turbines, could then be used for propulsion.
[0004] Several patents have described various aspects with such reliquefaction plants, and accordingly improvements to these. The prior art (e.g. Norwegian Patent Application No. 20051315 basically focuses on improvements of the nitrogen Brayton cycle and the utilization of cold nitrogen for pre-cooling. There is, however, a further need to improve the system in order to reduce the power demands.
[0005] Most of today's LNG vessels utilize low-temperature centrifugal BOG compressors to feed their boilers. Much of the reason for choosing low-temperature compression is that this will reduce the compressor size significantly compared to compression at ambient temperatures. The fan laws are applicable for centrifugal compressors, and show that a low suction temperature will ensure a higher pressure ratio per stage. The density of the gas will accordingly increase, the volume flow is reduced to a minimum, and the size and efficiency of the BOG compressors become more favourable.
[0006] Since there is no need to preserve the low temperature duty in the BOG stream—in fact the BOG is normally additionally heated before introduction to the boilers—the heat of compression is deliberately absorbed by the compressed gas without any means of heat rejection downstream the BOG compression.
[0007] The common practice of low.temperature BOG compression has been further applied to new BOG compressor designs, dedicated for operation towards LNG reliquefaction systems. From an energy point-of-view this results in inefficient operation, since the cooling cycle must be sized to remove the heat of compression from BOG compressors, in addition to the heat of evaporation and the superheating adsorbed in the cargo containment system.
[0008] Also, other problems arise when low-temperature BOG compression is applied. Since no aftercoolers (intercoolers) are employed, recycling at low capacities depend on temperature control upstream the BOG compressor. The cooling duty necessary for this purpose can be difficult to predict since it will depend much on the BOG compressor efficiency, which in turn depends on several properties of the processed stream. Using recondensed BOG to provide this cooling, also reduces the performance of the plant, measured in terms of power per unit reliquefied BOG returned to the tanks.
SUMMARY OF THE INVENTION
[0009] It is thus provided a method of A method of pre-heating LNG boil-off gas (BOG) stream flowing from a reservoir in a reliquefaction system, prior to compression, the method comprising heat exchanging the BOG stream in a first heat exchanger, against a second coolant stream having a higher temperature than the BOG stream, the method being characterized in that the second coolant stream is obtained by selectively splitting a first coolant stream into said second coolant stream and a third coolant stream, said third coolant stream being flowed into a first coolant passage in a reliquefaction system cold box, whereby the BOG has reached near-ambient temperatures prior to compression and heat exchange with low temperature BOG is done by optimising the split of the coolant in the first heat exchanger in order to minimize exergy losses, and thermal stresses in the cold box are reduced.
[0010] It is also provided a method for cooling an LNG boil-off gas (BOG) stream in a reliquefaction plant, the BOG flowing from a reservoir, the method comprising compressing the BOG; heat exchanging the compressed BOG against a coolant in a cold box; flowing substantially re-liquefied BOG from the cold box to the reservoir, characterized by prior to the compression step, pre-heating the BOG to substantially ambient temperatures, by heat exchanging the BOG with said coolant, said coolant prior to the heat exchange having a higher temperature than the BOG.
[0011] In one embodiment, the pressure of the reliquefied BOG between the cold box and the reservoir is controlled independently of the BOG compressor discharge pressure and the reservoir pressure, and the amount of vent gas generated and the vent gas composition thus may be controlled.
[0012] It is also provided an apparatus for cooling an LNG boil-off gas (BOG) in a reliquefaction system, comprising a closed-loop coolant circuit for heat exchange between a coolant and the BOG; a BOG compressor having an inlet side fluidly connected to an LNG reservoir; a cold box having a BOG flowpath with a BOG inlet fluidly connected to the BOG compressor outlet side; said BOG flowpath having outlet for substantially re-liquefied BOG, fluidly connected to the reservoir; said cold box further comprising coolant flowpaths for heat exchange between the BOG and the coolant; characterized by a first heat exchanger in the fluid connection between the reservoir and the BOG compressor inlet side, said first heat exchanger having a coolant path fluidly connected to the closed-loop coolant circuit, at a point downstream of the coolant circuit's compander aftercooler but upstream of the coolant flow paths in the cold box, whereby the BOG compressor receives BOG with temperatures near or at the system ambient temperatures.
[0013] In one embodiment, the invention provides a separator in fluid connection with the cold box outlet and with the reservoir, a first valve in the cold box outlet line and a second valve in a line connected to the reservoir, said separator also comprising a vent line ( 11 ), whereby the pressure in the separator may be controlled, and the amount of vent gas and the vent gas composition thus may be adjusted.
BRIEF DESCRIPTION OF THE DRAWING
[0014] FIG. 1 is a simplified process flow diagram, illustrating the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0015] The invention will now be described with reference to FIG. 1 , illustrating the novel features of the LNG RS with ambient temperature BOG compression. The figure shows schematic a cargo tank 74 , holding a volume of LNG 72 . BOG, evaporating from the LNG, enters a line 1 which is connected to a first heat exchanger H 10 . In this heat exchanger, the BOG is heated up to near-ambient temperatures, as will be described later. Following this pre-heating, the BOG enters the first stage BOG compressor C 11 via line 2 . The BOG compressor is shown as a three-stage centrifugal compressor C 11 , C 12 , C 13 , interconnected via lines 3 - 7 via intercoolers H 11 , H 12 and aftercooler H 13 as shown in the figure, but other compressor types may be equally applicable. The pre-heating ensures that the heat generated by the compression may be rejected through cooling water in the intercoolers H 11 , H 12 and the aftercooler H 13 .
[0016] Pressurized BOG is then, via a line 8 , fed into a second heat exchanger (or “cold box”) H 20 where it is heat exchanged against a coolant, as will be described later. The coolant is preferably nitrogen (N 2 ). Following heat exchange, substantially reliquefied BOG exits the cold box H 20 via a lines 9 , 10 connected to a separator F 10 . The separator is provided with a vent line 11 . A throttling valve V 10 is arranged in the lines 9 , 10 between the cold box and the separator, for expanding the reliquefied BOG. Following separation, reliquefied BOG is fed into the LNG 72 in the cargo tank 74 via lines 12 , 13 , as shown in FIG. 1 . A valve V 11 is arranged in the lines between the separator F 10 and the tank 74 , the purpose of which will be described later.
[0017] The closed N 2 -Brayton cooling cycle is here represented by a 3-stage compressor C 21 , C 22 , C 23 with intercoolers H 21 , H 22 , aftercooler H 23 , interconnected via lines 51 - 55 as shown in the figure, and a single expander stage E 20 . (Other cooling cycle constellations, for instance as discussed in Norwegian Patent Application No. 20051315 can also be utilized in this context.) Pressurized coolant (N 2 ) exits the compressor and the aftercooler H 23 via a line 56 connected to a three-way valve V 12 . The three-way valve V 12 is controllable to selectively split the high-pressure N 2 stream flowing in the line 56 into two different streams in respective lines 57 , 59 , as further detailed below. A first outlet of the three-way valve V 12 is connected to a coolant inlet in the first heat exchanger H 10 via a line 59 . A line 60 connects the coolant outlet of the first heat exchanger H 10 with the second heat exchanger's H 20 middle section, via line 61 , as shown in FIG. 1 . A line 57 connects a second outlet of the three-way valve V 12 to the inlet of a first coolant passage 82 in the second heat exchanger H 20 upper section. The first coolant passage 82 outlet is connected via a line 58 to an entry point on the line 60 described above. A line 61 connects this entry point to a the inlet of a second coolant passage 84 in the cold box, in the vicinity of the cold box' middle section, as illustrated by FIG. 1 . Coolant flows through the second coolant passage 84 and into an expander E 20 via a line 62 . The expanded coolant enters the second heat exchanger (cold box) H 20 lower section via a line 63 connected to the inlet of a third coolant passage 86 before it exits the heat exchanger and flows back to the compressor C 21 , C 22 , C 23 via the line 50 . The flow split here described as a three-way valve V 12 can equally be performed by other flow control configurations, such as normal single line control valves, orifices, etc. The important aspect is that the flow split can be controlled in order to cope with varying BOG flow conditions.
[0018] Generally, the process involves three new features which differ from previously suggested reliquefaction designs:
1. A heat exchanger H 10 , to ensure that most of the low-temperature duty which can be extracted from the BOG in the ship's vapor header line 1 , remains preserved within the reliquefaction system, 2. A BOG compressor C 11 , C 12 , C 13 working under ambient, or near-ambient conditions, with rejection of its heat of compression H 11 , H 12 , H 13 to the ambience; 3. A generally higher pressure for the BOG stream 8 entering the main heat exchanger (cold box) H 20 , compared to the discharge pressure of common BOG compressors, allowing the condensation to take place at a higher temperature level, and at the same time opens the possibilities for controlling the separation pressure in the separator F 10 at a level between the cold box outlet pressure in the line 9 and the storage pressure in the cargo tanks 74 . This pressure control must be seen in association with flow control through the separator vent line 11 (flow control valve not shown in FIG. 1 ). By adjusting the separation pressure, the vent flow, as well as the composition of the condensate which is returned to tanks 74 , can be controlled according to the operator preferences. Minimizing the vent gas flow results in higher required reliquefaction power input and vice versa. Adjustments of the separator pressure will therefore allow the operator to select the most favourable conditions for economic optimization of the LNG RS operation.
1. Heat Exchanger Upstream BOG Compressor
[0022] The heat exchanger H 10 upstream the BOG compressor C 11 , C 12 , C 13 is installed to preserve the low-temperature duty in the BOG coming from the tanks 74 , within the system. To extract as much low temperature duty as possible from this BOG stream, the BOG temperature should be allowed to increase up to near-ambient temperatures. To preserve the low temperature duty within the system, the duty must be absorbed by another stream in the reliquefaction system, originating at a higher temperature than the BOG stream.
[0023] This other stream will typically be a fraction of the warm high-pressure N 2 -stream 59 as shown in FIG. 1 . Other alternatives, such as using the entire N 2 -stream (not only a part of it), or the BOG-stream from downstream the BOG compressor's aftercooler are also possible. However, the process of FIG. 1 will probably be the most beneficial, given the limitations and characteristics of commonly employed equipment for such processes. Consequently, only the process of FIG. 1 , involving a split of the high-pressure N 2 -stream 56 downstream the N 2 -compander's aftercooler H 23 into two different streams 57 , 59 , will be discussed next.
[0024] The BOG pre-heater control is based on controlling the coolant flow (N 2 ) on the secondary side. The energy which is transferred between the compressed N 2 and the BOG in the first heat exchanger H 10 (pre-heater) will depend on the BOG flow and temperature, and consequently be a more or less fixed value [kW] as long as the BOG flow is constant. This means that the temperature of the N 2 flow exiting the pre-heater H 10 will vary with the N 2 flow rate. As long as the heat transfer area of the pre-heater is large enough, the three-way valve V 12 (or equivalent flow split constellations) in the N 2 stream upstream the pre-heater H 10 can be used for two different purposes:
A: For Thermodynamic Optimization of the Overall Process:
[0025] The freedom represented by the flow split (three-way valve V 12 ) can be used to ensure a very efficient heat exchange (low LMTD [log mean temp difference], and consequently low exergy losses) in the upper parts of the cold box H 20 . The heating and cooling curves can in theory be designed to be parallel with a constant temperature difference between streams at any temperature in the upper (warm) parts of the cold box.
[0026] Since the Brayton cycle is based on the concept that pressurized N 2 has a higher heat capacity than low pressure N 2 , the heating curves can only be made parallel if the high pressure mass flow is smaller than the cold, low pressure flow. The split of the high pressure stream will consequently cause a very efficient heat exchange in the upper parts of the cold box, and since the branch flow also is cooled independently in the BOG pre-heater, the energy penalty which otherwise would have been associated with the mixing of the two high pressure N 2 streams at a lower temperature is reduced to a minimum.
[0027] The flow split will typically be controlled based on the BOG compressor suction temperature.
B: For Reducing Thermal Stress in the Cold Box to a Minimum
[0028] Another benefit of the flow split control made possible by the three-way valve V 12 (or alternative flow split constellations), is that the temperature of the high pressure N 2 stream exiting the pre-heater H 10 and flowing in the line 60 , can be monitored and, if necessary, controlled in order to avoid rapid temperature fluctuations in the flow which is reintroduced to the cold box via the line 61 .
[0029] The cold box is normally made in aluminium and is sensitive to thermal stress. By applying a safety control function which changes the flow through the pre-heater based on undesirable conditions, the temperature of all streams entering the cold box can be carefully controlled. This would not have been possible if the pre-heater was a low pressure BOG vs. high pressure BOG heat exchanger, as the high temperature BOG outlet temperature would change synchronously with the fluctuation in the low pressure incoming BOG.
[0030] Normally, the split ratio defining the flows of streams 57 and 59 , will be adjusted in order to extract as much low temperature duty as possible from the low temperature BOG. However, this configuration also opens for controlling the split ratio with respect to the temperature of the nitrogen stream 61 entering the cold box' middle section. Doing so, conditions which may expose the main heat exchanger H 20 to damaging thermal stresses can easily be eliminated.
[0031] To achieve the optimal heat integration from a thermodynamic point-of-view, the heat exchangers H 10 and H 20 can be combined in one single multi-pass heat exchanger. However, since the main heat exchanger (cold box) H 20 typically will be a plate-fin heat exchanger, which to some extent is sensitive to both rapid temperature fluctuations and large local temperature approaches, it can be feasible to extract some of the heat transfer to an external heat exchanger of a more robust type, as shown at the pre-heater H 10 in FIG. 1 .
[0032] The heat exchanger configuration shown in FIG. 1 will also dampen the temperature fluctuations of the flow 61 entering the main heat exchanger's H 20 middle section, since the N 2 -coolant stream will be very large compared to the BOG flow. This will ensure a much safer operation with respect to thermal stresses in the cold box.
2. Ambient Temperature BOG Compressor
[0033] The main incentive for employing ambient temperature BOG compression is the possibility this offers for rejecting heat to the ambience. While today's commonly used BOG compressors preserves the compression heat within the BOG stream, the compression heat can now be delivered to an external source operating at ambient or near ambient temperatures (e.g. cooling water).
[0034] Ambient temperature compression also offers other benefits. Since an aftercooler H 13 as shown in FIG. 1 typically will be associated with this system, the temperature of the compressed stream 8 entering the cold box is stabilized relative to the heat rejection source's temperature. After- and intercooling also represent major advantages with respect to operation in recycle and/or anti surge modes, where the external cooling media ensures stable operation, normally without any additional temperature control.
[0035] Ambient temperature BOG compression is especially favourable for LNG vessels where boil-off rates, compositions, temperatures and pressures may vary considerably with the type of voyage (ballast or laden voyages) and cargo. Inter- and aftercooling towards ambient conditions will stabilize the compression conditions and ease capacity control (recycling, etc.)
3 . Benefits of Selecting a Higher Pressure Ratio
[0036] A “higher” pressure ratio over the BOG compressors C 11 ,C 12 ,C 13 will in this context relate to a higher cold box inlet pressure in the line 8 than what is strictly necessary to provide a sufficient differential pressure for forcing the LNG back to the cargo tanks.
[0037] This allows the cryogenic separator F 10 to be placed at an intermediate pressure level, typically limited to a zone between two valves V 10 , V 11 as shown in FIG. 1 . The pressure in this zone can then be controlled independently of the BOG compressor discharge pressure and the cargo tank pressure. Accordingly, some of the overall system's capacity control can be performed by pressure adjustments in this region. It will consequently enable the operator or the automated control system to adjust both the amount of vent gas generated as well as the vent gas composition in order to operate under the most economically favourable conditions during all LNG price fluctuations.
[0038] A dedicated line can also be placed in order to bypass the separator under conditions where reliquefied BOG is so much subcooled that the separation pressure otherwise will drop below a defined minimum value.
[0039] The pressure differential between the main heat exchanger H 20 and the separator F 10 ensures that the separator can be placed more independent of the main heat exchanger.
[0040] A higher BOG compressor discharge pressure will increase the gain (either in form of a higher adiabatic temperature change or reduced flash gas generation) during the throttling processes down to tank pressure.
[0041] Last, a higher process pressure will increase the heat transfer coefficient in heat the main heat exchanger H 20 and ensure that the condensation here will be performed at higher temperatures in order to reduce exergy losses.
[0042] The person skilled in the art will appreciate that the purpose of the three-way valve V 12 is to selectively control the flow split between (i) the line 59 connected to the first heat exchanger H 10 and (ii) the line 57 connected to the cold box H 20 . To this end, the three-way valve V 12 described above may be replaced by e.g. a controllable choke valve in the line 60 , downstream of the first heat exchanger H 10 , and a fixed-dimension restriction in the line 57 . | A method and apparatus of pre-heating LNG boil-off gas stream flowing from a reservoir in a reliquefaction system, before compression. The method comprises heat exchanging the BOG stream in a first heat exchanger, against a second coolant stream having a higher temperature than the BOG stream, where the second coolant stream is obtained by selectively splitting a first coolant stream into second and third coolant streams, third coolant stream being flowed into a first coolant passage in a reliquefaction system cold box, whereby the BOG has reached near-ambient temperatures prior to compression and the low temperature duty from the BOG is substantially preserved within the reliquefaction system, and thermal stresses in the cold box are reduced. Before the compression step, the BOG is pre-heated to substantially ambient temperatures, by heat exchanging the BOG with said coolant, said coolant prior to the heat exchange having a higher temperature than the BOG. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a building structure which is portable and collapsible. The building structure is lightweight and collapsible to a compact shipping and transporting position. This is accomplished by a plurality of hinge assemblies that permit the side and end walls, roof and floor to lie flat upon one another to minimize the size of the building structure in its collapsed position.
2. Description of the Prior Art:
In manufacturing facilities, it is commonplace to protect parts and assemblies during manufacturing from airborne contaminants, such as dust, particles, water, etc., so as to prevent such contaminants from contacting the parts during assembly or during idle downtime. This is particularly important in painting, spraying and coating operations which require extreme cleanliness of the prepared surface before painting, etc., and protection of the painted surface until the paint has completely dried.
To accomplish this, it is common to surround painting and spraying areas in a manufacturing facility with an enclosure to retain airborne paint particles within the enclosure and to prevent other contaminants from contacting the part surfaces. Such enclosures typically incorporate a skeletal framework of spaced, interconnected members to which a number of frame panels, typically rigid members made of steel or other material, are mounted.
While the use of such a building structure is effective at containing the airborne particles within a given area or protecting parts from airborne contaminants, the cost of such a rigid panel enclosure is high especially since long distances must be covered and considerable installation time is required to install the framework in the manufacturing facility and to attach the rigid panels thereto. The high cost of previously devised enclosures has prevented their use over large portions of conveyor lines in manufacturing plants and, thus, the parts are left unprotected after painting, spraying, coating, etc., and between initial surface preparation and painting etc., and are vulnerable to dust, water and other airborne contaminants.
Building structures have also been designed for other applications, such as greenhouses, tents, etc., which use a single, flexible sheet or cover which is placed over and attached to a skeletal framework. This building structure also forms an effective containment shield or barrier surrounding a given area. However, it has been found that it is difficult and time consuming to install a large, single piece cover to a large skeletal framework. This increases installation time and adds to overall manufacturing costs.
Thus, it would be desirable to provide a containment shield which can be installed at the use site in a minimum amount of time. It would also be desirable to provide a contaminant shield which has reduced manufacturing costs. It would also be desirable to provide a contaminant shield which does not require a skeletal framework to be installed at the use site for attachment of rigid frame panels thereto. Finally, it would be desirable to provide a contaminant shield which can be constructed in any configuration for widespread use in many different applications.
The increasing world population (now five billion) has led to housing shortages worldwide. These shortages are also increasing due to the number of people left homeless from natural disasters. Accordingly, there is a need for low cost housing that may be easily transported and assembled where needed, and later disassembled and moved.
While many attempts have been made to provide portable building structures, these structures suffer from numerous disadvantages. Many of these structures are heavy, complex and costly to make, and difficult to assemble and disassemble. In addition, many of these building structures require constant maintenance; for example, wooden structures tend to splinter and constantly need to be waterproofed. Moreover, these building structures tend to corrode due to air pollutants and rust, rot or mildew due to adverse weather conditions. Also, many of the prior art devices require special tools for assembly and disassembly.
Examples of these prior building structures are disclosed in the following U.S. Pat. Nos.: U.S. Pat. No. 617,043 to Phifer; U.S. Pat. No. 1,062,976 to Jackson; U.S. Pat. No. 1,149,213 to Neuberth; U.S. Pat. No. 1,469,525 to Nadolney; U.S. Pat. No. 1,481,142 to Minton et al; U.S. Pat. No. 2,207,836 to Sundell; U.S. Pat. No. 2,591,984 to Walsh; U.S. Pat. No. 3,189,949 to Hurkamp; U.S. Pat. No. 3,341,987 to Johansson; U.S. Pat. No. 3,434,253 to Hatcher; U.S. Pat. No. 3,452,501 to Zimmer et al; U.S. Pat. No. 3,562,973 to Gangemi; U.S. Pat. No. 3,566,554 to Schaffer et al; U.S. Pat. No. 3,781,944 to Gianardi; U.S. Pat. No. 3,984,949 to Wahlquist; U.S. Pat. No. 3,886,676 to Alfonso; U.S. Pat. No. 4,035,964 to Robinson; U.S. Pat. No. 4,166,343 to O'Brian et al; U.S. Pat. No. 4,439,969 to Bartlett; U.S. Pat. No. 4,544,300 to Lew et al; U.S. Pat. No. 4,641,475 to Berridge; U.S. Pat. No. 4,641,985 to Bard et al; U.S. Pat. No. 4,649,684 to Petree et al; U.S. Pat. No. 4,652,170 to Lew; U.S. Pat. No. 4,696,132 to LeBlanc; U.S. Pat. No. 4,726,155 to Nahmias; and U.S. Pat. No. 4,742,653 to Napier et al.
This invention addresses these needs discussed above in the art, along with other needs which will become apparent to those skilled in the art once given this disclosure.
Numerous innovations for a collapsible structure having shipping properties have been provided in the prior art that are described as follows. Even though these innovations may be suitable for the specific individual purposes to which they address, they differ from the present invention as hereinafter contrasted.
U.S. Pat. No. 5,183,427
Collapsible toy building
A. Allen Draper
A toy collapsible house. A column of stacked segments supports the house, held together by a spring tensioned cord, impact triggered release of which slides stiff cord portions away from segment junctions, allowing column and house collapse. The column cord is lifted from above the roof to reassemble the house.
U.S. Pat. No. 4,732,285
Collapsible structure
Heinrich Wuster
A collapsible structure consisting of an umbrella-like clothes drier or of a garden umbrella comprises a central tube and a folding frame, which carries a clothesline or a covering. A flexible sheath is provided, which is adapted to be slipped over the folding frame when it is collapsed. The flexible sheath may be sack-like (closed at one end and open at the other) and in that case may be accommodated in the central tube when the same is open-topped, or in a storage container, which is open-topped and is parallel to and extends beside the central tube. Alternatively the sheath may be tubular (open at both ends) and accommodated in a storage container which concentrically surrounds the lower portion of the central tube. The sack-like sheath can be pulled out of the central tube or the juxtaposed storage container at its top end and over an upwardly convex, annular guiding hood and can then be slipped from above over the collapsed folding frame. The tubular sheath can be pulled out of the open top of the concentric storage container and can be slipped from below over the collapsed folding frame. A rope or a spring, which is secured in the juxtaposed storage container or to the central tube on the inside thereof, is secured to the sack-like sheath and can be used to retract the sheath into the central tube of the juxtaposed storage container.
U.S. Pat. No. 4,754,774
Collapsible shelter
Ashley Leader
A collapsible structure adapted to be mounted on a supporting base such as a motor vehicle. The collapsible structure includes a roller journalled on a supporting structure and to which one end of a flexible roof panel is secured for rolling and unrolling. A supporting structure including a frame comprising a pair of transversely spaced tracks provide a guide for supporting guide members carried at the ends of the roof panel for assisting in its rolling and unrolling operation.
U.S. Pat. No. 4,696,132
Foldable shelter system and method of construction
J. T. LeBlanc
A habitable shelter and method of construction having a continuous floor portion with a plurality of four exterior walls attached to the floor portion via a hinge means along contiguous sides, the walls movable between horizontal positions along the floor to vertical upright wall positions. There is further provided means for allowing the walls to lay parallel to the floor, with the end walls foldable atop the side walls, and a plurality of exterior walls stacked between the folded end walls for compact storage for shipment. There is further provided a plurality of corner beam members for stabilizing the walls in their upright position in interlocking fashion, and a roof member positioned atop the vertical walls for defining an angulated roof on the structure. There is further provided a plurality of interior walls which in their upright position are doweled into the floor portion and interlocked into the side walls for further support.
5,107,639
Portable and collapsible building structure
J. Cecil Morin, and James A. Loggie
A portable and collapsible building structure including a floor, a pair of side walls, a roof and a pair of end walls. The side walls each include a lower and upper panel pivotally coupled at their inner edges by a first hinge assembly. The outer edges of the side walls are pivotally coupled to the floor and roof by a second hinge assembly. The end walls are pivotally coupled to the roof by a third hinge assembly and releasably coupled to the floor and side walls by a C-shaped coupling chip. The first, second and third hinge assemblies permit the building structure to collapse so that the upper and lower panels of each side wall lie substantially flat between the floor and the roof, while the end walls pivot 270 degree. So as to lie substantially flat upon the roof. The first, second and third hinge assemblies include a plurality of one-piece, extruded, coupling channels, a plurality of hinge inserts, at least one hinge pin, and a C-shaped coupling clip.
U.S. Pat. No. 4,860,778
Contaminant shield and method of constructing same
Ronald R. Pohl
A contaminant shield prevents airborne contaminants from contacting manufactured parts in a work area in a manufacturing facility. The contaminant shield is formed of a plurality of like frames, each formed of a plurality of interconnected side frame members covered by a flexible sheet attached at its outer edges to the side frame members. The frames are interconnected at adjacent edges to form the complete contaminant shield. A sealing strip is applied to the joints between adjacent frames to form a continuous contaminant barrier in conjunction with the flexible sheet attached to each frame. The contaminant shield is constructed by first constructing a plurality of frames by interconnecting side frame members into a rigid, planar frame and attaching the edges of a flexible sheet to each side frame member of the frame. Each of the side frame members includes an aperture which receives a complimentrally shaped cap which traps the edges of the flexible sheet between itself and the aperture in the side frame for securely attaching the flexible sheet to the side frame.
Numerous innovations for a collapsible structure having shipping properties have been provided in the prior art that are adapted to be used. Even though these innovations may be suitable for the specific individual purposes to which they address, they would not be suitable for the purposes of the present invention as heretofore described.
SUMMARY OF THE INVENTION
The collapsible structure having shipping properties of the present invention is formed of a plurality of frames of a configuration which are interconnected in a predetermined configuration to surround or cover an area. The frames are formed of a plurality of hinged end, side and roof frame members which are joined together into an integal, planar assembly having a predetermined shape. The side frame members surround an interior opening.
A plurality of such frames, having the same or different configuration are interconnected together to form a collapsible structure having shipping properties having any desired shape. For example, a plurality of frame members may be interconnected to form a three-sided floor-mounted enclosure having opposed side walls joined together by a top. Similarly, the frame members may be joined together to form an elongated planar cover having depending side walls which covers a work area in a manufacturing facility.
In one embodiment, means for attaching the edges of a flexible sheet to the side frame members of a frame are provided. Preferably, the attaching means comprises each side frame member having opposed side walls joined together at one end by an integral, central portion. The opposite ends of the side walls are each formed with an inwardly and downwardly hinge, with the inner faces of the hinge being spaced apart to define an aperture opening into the hollow interior of each side frame member. A member has first and second end portions, with the first end portion being complimentary shaped to the configuration of the aperture in the side frame members. The second end portion of the member has an enlarged cross section with hinge extending outward from the first end portion. The first end portion of a member is inserted into the aperture in a side frame member to trap an edge of the sheet between first end portion and the side frame member to securely attach the sheet to the side frame member. Members are inserted into the remaining side frame members of a frame to securely attach the sheet to the frame.
After the collapsible structure having shipping properties are constructed at the manufacturing facility, they are shipped to the use site and arranged to be formed having a predetermined configuration. After the frames are joined together as described above to form an enclosure, shield, cover, etc., the joints between adjacent side frame members of adjacent frames are sealed by a hinge, for example, to provide a continuous, protrusion free surface in conjunction with the sheet which provides no dust collection surfaces within or under the contaminant shield and effectively blocks the interior space enclosed or covered by the contaminant shield from airborne contaminants, such as particles, dust, water, etc.
In a preferred embodiment, each of the side frame members has opposed side walls interconnected by a central portion. In attaching the sheet to the frame according to the method of the present invention, the sheet is first loosely placed over one entire side of the frame covering all of the side frame members. Tension is applied to one edge of the sheet while the cap member is slidably inserted into one of the side frame members trapping the edge of the sheet between itself and the side frame member.
The collapsible structure having shipping properties of the present invention provides many unique advantages in constructing collapsible structure having shipping properties or barriers for manufacturing facilities since it minimizes installation time and has a reduced manufacturing cost. By constructing the individual frames at the frame manufacturing site, the need for constructing and installing a skeletal frame at the use site is eliminated. This reduces installation time. Also, the advantages of mass production of identical or nearly identical frames is attained thereby reducing the overall manufacturing cost of the collapsible structure having shipping properties. Since the collapsible structure having shipping properties of the present invention finds advantageous use with conveyor lines or other elongated work areas, the collapsible structure having shipping properties will contain a large number of identical frames thereby enabling the economies of mass production of the identical modular frames at the frame manufacturing site to be realized.
The collapsible structure having shipping properties of the present invention, once installed at the use site, provides an effective barrier which prevents airborne contaminants, such as dust, particles, water etc., from contacting work parts or assemblies in a given area within a manufacturing facility.
Accordingly, a primary object of the present invention is to provide a building structure which is readily and easily assembled and disassembled without the need of any tools.
Another object of the present invention is to provide a collapsible structure having shipping properties that is portable.
Still another object of the present invention is to provide a collapsible structure having shipping properties that is lightweight and very strong.
Yet another object of the present invention is to provide a collapsible structure having shipping properties that is very compact so that it can be easily transported.
Yet another object of the present invention is to provide a collapsible structure having shipping properties that has very low maintenance.
Yet another object of the present invention is to provide a collapsible structure having shipping properties that will not rust, rot or mildew and is highly resistant to most weather conditions.
Yet another object of the present invention is to provide a collapsible structure having shipping properties that is relatively inexpensive to manufacture and uses a series of extruded channels to form the required hinges.
Yet another object of the present invention is to provide hinge assemblies that require relatively no assembly.
Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention.
The novel features which are considered characteristic for the invention are set forth in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of the specific embodiments when read and understood in connection with the accompanying drawing.
LIST OF REFERENCE NUMERALS UTILIZED IN THE DRAWING
10--collapsible structure having improved shipping and storing properties
12--hinge
14--front end
16--door
18--front end edge
20--piano hinge
22--downward direction
24--right roof
26--right upper side
28--right lower side
30--rear end
32--floor
34--left roof
36--left upper side
38--left lower side
40--left inward direction
42--right inward direction
44--inward collapsible direction
46--front door
48--downward collapsible direction
BRIEF DESCRIPTION OF THE DRAWING
FIG.1 is a perspective view of the collapsible structure having improved shipping and storing properties fully erected exhibiting the following features; hinge, front end, door, front end edge, piano hinge, right roof, right upper side, right lower side, floor, and left roof.
FIG. 2 is a perspective view of the collapsible structure in the initiation collapsing stage having improved shipping and storing properties exhibiting the following features; hinge, front end, door, front end edge, piano hinge, downward direction, right roof, right upper side, right lower side, rear end, floor, left roof, left upper side, left lower side, and front door.
FIG. 3 is a perspective view of a collapsible structure in the collapsing stage having improved shipping and storing properties exhibiting features such as a hinge, front end, piano hinge, downward direction, right roof, right upper side, right lower side, left roof, left upper side, left lower side, left inward direction, right inward direction, inward collapsible direction, and front door.
FIG. 4 is a perspective view of a collapsible structure in the fully collapsed configuration for storing and shipping exhibiting the following features; hinge, piano hinge, right roof, right upper side, right lower side, floor, left roof, left upper side, left lower side, and downward collapsible direction.
FIG. 5 is a diagrammatic representation of the method by which the structure is erected and collapsed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Firstly, referring to FIG. 1 which is a perspective view of the collapsible structure having improved shipping and storing properties 10 fully erected exhibiting the following features; hinge 12, front end 14, door 16, front end edge 18, piano hinge 20, right roof 24, right upper side 26, right lower side 28, floor 32, and left roof 34. The collapsible structure 10 is easily assembled and disassembled in minutes by the method as exhibited in FIGS. 2,3 and 4.
Referring now to FIG. 2 which is a perspective view of the collapsible structure 10 in the initiation collapsing stage having improved shipping and storing properties exhibiting the following features; hinge 12, front end 14, door 16, front end edge 18, piano hinge 20, downward direction 22, right roof 24, right upper side 26, right lower side 28, rear end 30, floor 32, left roof 34, left lapper side 36, left lower side 38, and door opening 46. To commence the collapsing of the structure 10, first push the front end 14 in a downward direction 22 followed by pushing secondly the rear end 30 in a similar downward direction 22, thus collapsing the front end 16 and/or rear end 30 on top of one another.
Referring now to FIG. 3 and FIG. 5 which are a perspective view of a collapsible structure 10 and a method of collapsing, respectively, in the collapsing stage having improved shipping and storing properties exhibiting features such as a hinge 12, front end 14, piano hinge 20, downward direction 22, right roof 24, right upper side 26, right lower side 28, left roof 30, left upper side 36, left lower side 38, left inward direction 40, right inward direction 42, inward collapsible direction 44, and door opening 46. After the front end 16 and rear end 30 have been fully collapsed, the third step is simultaneously collapsing the left side and right side in a left inward direction 40 and right inward direction 42 respectively, hence, lowering the left roof 34 and right roof 24.
Lastly, referring to FIG. 4 and which is a perspective view of a collapsible structure 10 in the fully collapsed configuration for storing and shipping exhibiting the following features; hinge 12, piano hinge 20, right roof 24, right upper side 26, right lower side 28, floor 32, left roof 34, left upper side 36, left lower side 38, and downward collapsible direction 48. When the collapsible structure 10 is fully collapsed, it is in a compact configuration having the right roof 24 directly on top of the right upper side 26 which is directly on top of the right lower side 28 which is directly on top of one half of the front end 14 and rear end 30 which are directly on top of one half of the floor 32. Similarly, when the collapsible structure 10 is fully collapsed, it is in a compact configuration having the left roof 34 directly on top of the left upper side 36 which is directly on top of the left lower side 38 which is directly on top of one half of the front end 14 and rear end 30 which are directly on top of one half of the floor 32. All parts of the collapsible structure are collapsible by virtue of hinges 12 and 20 which may be of varying configurations and types depending upon varying preferred embodiments of the present invention.
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 constructions differing from the type described above.
While the invention has been illustrated and described as embodied in a collapsible structure having improved shipping and storage properties, it is not intended to be limited to the details shown, 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.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims. | The present invention relates to a collapsible structure having improved storage and shipping properties which are achieved by specific designing of the size, shape and hingeable connection positions whereas said structure is erectable and collapsible within minutes utilizing a minimal amount of tools and effort. | 4 |
DESCRIPTION
This invention relates to an improved disc separator, and has for an object thereof the provision of a new and improved disc separator.
Another object of the invention is to provide a disc separator in which discs are mounted on retainers to form multiple disc units which are mounted end-to-end on shafts.
A further object of the invention is to provide a multiple disc unit in which longitudinal retainer segments have slots receiving internal teeth of annular discs to hold the discs in parallel, axially aligned positions.
Another object of the invention is to provide a multiple disc separator unit in which internal splines of annular discs project through slots in three or more arcuate retainer segments and are held by the retainers.
In the drawings:
FIG. 1 is a fragmentary, exploded view of an improved disc separator forming one embodiment of the invention;
FIG. 2 is an enlarged, vertical, sectional view of the separator of FIG. 1;
FIG. 3 is a fragmentary, enlarged view taken along line 3--3 of FIG. 2; and,
FIG. 4 is an enlarged, fragmentary top plan view of the separator of FIG. 1.
Referring now in detail to the drawings, an improved disc separator shown therein and forming a specific embodiment of the invention includes a frame 10 having sides 12 and a plurality of rotatable disc assemblies 14 and 16 mounted rotatably on the frame in parallel positions. The disc assemblies have interleaving separator discs 18 and 20 and are identical except for the staggered positions of the discs, and, hence, only the assembly 14 will be described in detail.
The disc assembly 14 comprises multiple disc units 30 mounted end-to-end on a shaft assembly 32 and clamped between abutments 34 on the ends of the shaft to lock the units on the shaft against longitudinal movement relative to the shaft and to key the units to the shaft. Each unit 30 includes a retainer 40 including three arcuate retainer segments 41, 42 and 43 having notch-like, half width end slots 46, inner slots 48 and side edge slots 50. The discs are annular and have equiangularly spaced inner teeth or splines 52 and 54, the splines 54 being somewhat arcuately longer than the splines 52. The arcuate length of each spline 54 is equal to the arcuate length of each inner slot 48 and those of the end slots 46 aligned longitudinally with the inner slots so that the splines 54 which are positioned in the inner slots 48 and those of the end slots aligned with the slots 48, key the discs to the retainer segment through which the splines 54 extend. This precisely locates the discs circumferentially relative to the retainer. The splines 52 are somewhat less wide (less in arcuate length) than the slots 48 to provide clearance for assembling the retainer segments in the discs.
The length or radial height of the splines 52 and 54 of each disc 18 is somewhat greater than the thickness of the retainer segments 41, 42 and 43, and the segments are held in positions fully expanded radially by swaged portions 60 of at least one of the splines 52 and 54 projecting through each segment. The splines have inner arcuate edges 62 lying in a cylinder and fitting closely on a cylindrical tube 64 of the shaft assembly 32. The splines 52 and 54 of each disc 18 are separated by arcuate lands 66 lying in a cylinder and the retainer segments are pressed against the lands 66 by the swaged portion 60.
The splines 52 and 54 all have the same thickness, which is just slightly less than the width of each of the slots 48 and 50. The width of each end slot 46 is no greater than one-half the thickness of the splines so that the splines of the end discs are firmly held between the two adjacent retainers. The retainer 40 is cylindrical, and each of the segments 41, 42 and 43 subtends an angle of slightly less than 120° so that the segments can be radially expanded easily onto the splines during the assembly of the unit. Thus, edge slots 50 are not quite half as long as the inner slots 48. The slots for each disc are staggered relative to the slots for the discs immediately adjacent to that disc.
In a preferred embodiment of the invention, the diameter of the tube 64 is six and one-half inches, the thickness of the retainer segments 41, 42 and 43 is three-sixteenth of an inch and the height of the splines is one-quarter of an inch. The retainer segments may be of steel and may be formed by punching the slots through a flat sheet of steel with a numerically controlled punching machine, cutting the segments and forming the segments to their arcuate shape. The tolerances of the width of the slots is thus held to plus or minus one thousandth of an inch, non-accumulative. The discs 18 and 20 may be punched from stainless steel sheet material.
In operation, the disc assemblies 14 and 16 are connected to a suitable drive mechanism (not shown) so that each is driven in the same direction. Material to be separated or graded is then fed on to the top of the table of discs at the feed end. The motion of the discs will cause the material supported on the discs to be propelled toward the opposite end of the table. Material having a dimension less than the spacing between the interleaved discs will fall through between the discs, the larger material being carried on the top eventually to be discharged off the end opposite the feed end. Many types of materials can be processed. For example, pulp chips can be separated from knots, wood chunks, frozen lumps or the like. Disintegrated materials, such as, ground up domestic waste can be screened to separate the finer particles for combustion processes from the larger particles for other types of processing.
While the retainer 40 is shown as made up of three segments 41, 42 and 43, for larger diameter shafts, it may be desirable to use more than three segments, each such segment being less than 120°, of course. | An improved disc separator in which discs are mounted on retainers to form multiple disc units and the units are mounted end-to-end on a shaft and are clamped in place thereon. The discs have internal splines that project through and beyond splining slots in segments of the retainer, one spline only on each disc being wider than the others and adapted to fit closely in any of the slots in the retainer. The splines project slightly beyond the inner surface of the retainer and are swaged to hold the retainer segments rigidly in fully expanded positions. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates generally to motorcycle maintenance, and more specifically, to a method and gauge for alignment of a motorcycle rear axle.
[0003] 2. Description of Related Art
[0004] In any wheeled vehicle it is important that the proper alignment of the wheels be maintained for safe and efficient operation of the vehicle. This is especially true for two wheeled vehicles, such as motorcycles, due to the danger of harm to the operator in the event of an accident. For many motorcycles, including most chain and belt driven models, the axle of the rear wheel is adjustable in order to allow adjustment of the tension on the chain or belt to a specified parameter. The rear axle may be prone, however, to misalignment due to the adjustability of the axle. When the rear axle is misaligned, excessive wear may be caused to drive-train components and the tires, and the handling characteristics of the motorcycle may be impaired, potentially increasing the likelihood of an accident.
[0005] One method of aligning the rear axle involves counting the number of threads visible on the exposed shaft of one or more of the rear axle adjustment screws or bolts. This method is problematic because it is inaccurate, tedious, and time-consuming.
[0006] These problems are exacerbated by the frequency with which the rear axle may need to be adjusted or removed for repairs or proper maintenance of the motorcycle's components. Each time the rear axle is adjusted or removed, large amounts of time may be required to adjust the position of the rear axle to ensure that there is a proper amount of tension on the chain or belt, and that the rear axle is properly aligned.
[0007] It is desirable, therefore, to provide a method of aligning the rear axle of a motorcycle that is more accurate and that can be accomplished in less time, thereby reducing or eliminating the disadvantages of known methods of aligning the rear axle during routine safety checks or after maintenance and/or repairs.
BRIEF SUMMARY OF THE INVENTION
[0008] Briefly described, in a preferred embodiment, the present invention overcomes the above-mentioned disadvantages and meets the recognized need for such a method and device by providing a motorcycle rear axle alignment gauge comprising a housing, a probe movably engaged with the housing, and an indicator operably engaged with the probe.
[0009] According to one aspect of the preferred embodiment, the housing includes at least one portion adapted to abut a reference portion of the motorcycle.
[0010] According to another aspect of the preferred embodiment, the indicator comprises a rotating needle.
[0011] According to another aspect of the preferred embodiment, a scale is arranged around a peripheral portion of a face of the housing.
[0012] According to another aspect of the preferred embodiment, the indicator comprises an electronic display.
[0013] According to another aspect of the preferred embodiment, the gauge may be calibrated.
[0014] Accordingly, a feature and advantage of the present invention is its ability to quickly and accurately ascertain a distance between an end of a rear axle adjustment screw and a portion of a motorcycle frame.
[0015] Another feature and advantage of the present invention is its ability to quickly and accurately compare the position of a first side of an axle with a position of the second side of the axle.
[0016] Another feature and advantage of the present invention is its ability to quickly and accurately align an axle of a motorcycle.
[0017] According to another aspect, the present invention comprises a method of aligning a rear axle of a motorcycle comprising the steps of measuring a first position of a first rear axle adjustment device relative to a first portion of an axle-mounting structure of a motorcycle, and adjusting the first rear axle adjustment device to align the rear axle of the motorcycle.
[0018] These and other objects, features, and advantages of the invention will become more apparent to those ordinarily skilled in the art after reading the following Detailed Description and Claims in light of the accompanying drawing Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Accordingly, the present invention will be understood best through consideration of, and reference to, FIGS. 1-6 , viewed in conjunction with the Detailed Description of the Preferred Embodiment referring thereto, in which like reference numbers throughout the various Figures designate like structure and in which:
[0020] FIG. 1 is a front view of a preferred embodiment of the present invention;
[0021] FIG. 2 is a front partial cutaway view of the preferred embodiment of the present invention;
[0022] FIG. 3 is a side view of a rear axle of a motorcycle;
[0023] FIG. 4 is a partial cutaway view of the preferred embodiment of the present invention shown in use;
[0024] FIG. 5 is a side view of a rear axle of a motorcycle according to an alternative design; and
[0025] FIG. 6 is a front view of the preferred embodiment shown in use with the motorcycle of FIG. 5 .
[0026] It is to be noted that the drawings presented are intended solely for the purpose of illustration and that they are, therefore, neither desired nor intended to limit the invention to any or all of the exact details of construction shown, except insofar as they may be deemed essential to the claimed invention.
DETAILED DESCRIPTION OF THE INVENTION
[0027] In describing preferred embodiments of the present invention illustrated in FIGS. 1-6 , specific terminology is employed for the sake of clarity. The invention, however, is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.
[0028] In that form of the preferred embodiment of the present invention chosen for purposes of illustration, FIG. 1 shows gauge 100 . Gauge 100 preferably comprises indicator 110 which is preferably operably connected to probe 120 , and further comprises housing 130 . More specifically, probe 120 is preferably slidably engaged with sleeve 121 such that probe 120 is free to travel, at least within a range, in a direction of the longitudinal axis of probe 120 and sleeve 121 , as indicated by arrow 140 . Probe 120 preferably comprises first end 120 a , adapted to contact a first reference surface, and a second end, not shown, disposed within casing 111 . Casing 111 may further optionally be rotatable with respect to sleeve 121 . Sleeve 121 is preferably attached to casing 111 such that sleeve 121 is, at least selectively, not separable from casing 111 . As such, when sleeve 121 is not separable from casing 111 , the second end of probe 120 is preferably in operable engagement with indicator 110 such that movement of probe 120 in the direction of arrow 140 relative to sleeve 121 (and thus casing 111 ), indicator 110 moves in the direction of arrow 150 to indicate a value proportional to such movement of probe 120 . The form of the operable engagement may take any of a variety of forms, such as geared, pivotal, levered, direct, rotational, or other mechanical form of engagement as will be understood by one skilled in the art. Alternatively, the engagement can be inductive, magnetic, resistive, optical, or other electronic or non-contact engagement configured and arranged to convert movement of probe 120 to a change in a value indicated by indicator 110 .
[0029] A preferred one of such engagement forms includes teeth disposed along a length of the second end of probe 120 in engagement with a rotatable gear, wherein movement along the longitudinal axis of probe 120 in the direction of arrow 140 translates to rotation of the gear, and needle 113 in fixed connection with the gear, such that rotation of the gear in response to motion of probe 120 causes rotation of needle 113 in the direction of arrow 150 . In such an embodiment, indicator 110 preferably includes scale 117 disposed on face 115 retained in casing 111 . It should be understood, however, that indicator 110 may alternatively comprise a digital or analog electronic display, such as an LCD.
[0030] Regardless of the specific structure utilized to translate movement of probe 120 to an indication, indicator 110 preferably includes a calibration feature. In the preferred embodiment, indicator 110 preferably includes calibration portion 119 in the form of a button. Operation of calibration portion 119 , such as by pushing the button, preferably disengages probe 120 from needle 113 such that a position of needle 113 relative to scale 117 may be adjusted independent of the movement of probe 120 . Preferably, operation of calibration portion 119 takes the teeth of probe 120 out of engagement with the rotatable gear. Thus, for a given position of probe 120 , the position of needle 113 relative to scale 117 may be adjusted to a predetermined position, such as a position associated with a zero mark of scale 117 . Alternatively, however, other calibration portions may be implemented. One such alternative calibration portion comprises a rotatable face 115 , whereby rotation of face 115 adjusts a position of needle 113 relative to scale 117 . Another alternative calibration portion comprises threaded fastener 139 in threaded engagement with housing 130 such that loosening threaded fastener 139 allows adjustment of a position of sleeve 121 , and, thus first end 120 a of probe 120 for a give position relative to sleeve 120 , relative to housing 130 . Subsequent tightening of threaded fastener 139 preferably retains sleeve 121 in fixed engagement with housing 130 .
[0031] Now referring to FIG. 2 , gauge 100 is shown with sleeve 121 in fixed engagement with housing 130 due to threaded fastener 139 being in a tightened position, thereby retaining sleeve 121 in friction force fixed engagement with a sidewall of bore 231 . When sleeve 120 is in such fixed engagement with housing 130 , a position of needle 113 relative to scale 117 due to a position of first end 120 a of probe 120 within bore 230 indicates a distance D between first end 120 a of probe 120 relative to forward surface 233 of housing 130 .
[0032] Now referring to FIG. 3 , motorcycle 300 includes rear tire 320 and rear wheel 321 , rotatably connected thereto by rear axle 301 . For proper operation, rear axle 301 must be maintained in a proper alignment relative to rear axle mounting structure 303 , in which rear axle 301 is carried. Furthermore, rear axle 301 must be maintained in a proper position within an adjustment portion, such as slot 307 , of rear axle mounting structure 303 in order to maintain a proper tension of belt (or chain) 310 .
[0033] In use, gauge 100 may preferably be used to determine whether rear axle 301 is in proper alignment by comparing measurements of a position of each side of a rear axle 301 within respective slots, such as slot 307 . In order to make such a determination, a user may first adjust a drive-train side of axle 301 within a drive-train side adjustment slot using a drive-train side rear axle adjustment device so as to provide a proper or desired tension on a belt or chain of the drive-train. The user may then preferably measure a position of a first side of an axle within a slot by contacting forward surface 233 with a reference surface of a drive-train side rear axle mounting structure in which the drive-train side adjustment slot is disposed, thereby contacting first end 120 a with a reference surface of the drive-train side rear axle adjustment device. The user may then read a first value indicated on indicator 110 representing a distance between the reference surface of the drive-train side rear axle adjustment device and the reference surface of the drive-train side rear axle mounting structure. The user may then measure a position of a second side of the axle by contacting forward surface 233 with reference surface 403 of the other rear axle mounting structure 303 , thereby contacting first end 120 a with reference surface 405 of the other rear axle adjustment device 305 . The user may then read a second value indicated on indicator 110 representing a distance between reference surface 405 and reference surface 403 (equal to distance D of FIG. 2 ). If the first value and the second value are equal, then the user may determine that rear axle 301 is in proper alignment due to the respective lengths of the drive-train side rear axle adjustment device and rear axle adjustment device 305 being equal. If the first value and the second value are different, however, the user may adjust rear axle adjustment device 305 , for example by tightening or loosing, in order to align rear axle 301 until a value of a measurement of the position of rear axle 301 in slot 307 is equal to the first value.
[0034] Alternatively, the user may determine whether rear axle 301 is in proper alignment by measuring a position of a first side of rear axle within a first slot by contacting forward surface 233 with a reference surface of a drive-train side rear axle mounting structure in which the drive-train side adjustment slot is disposed, thereby contacting first end 120 a with a reference surface of the drive-train side rear axle adjustment device. The user may then optionally calibrate gauge 100 such that the value indicated is a predetermined value, such as zero. Such calibration may be accomplished by rotating face 115 such that needle 113 points to, or otherwise indicates, a zero value of scale 117 . Alternatively, an electronic zeroing may be performed by activating a calibration portion of an electronic circuit comprising indicator 110 . Once gauge 100 has been calibrated, the user may then measure a position of a second side of rear axle 301 by contacting forward surface 233 with reference surface 403 of the other rear axle mounting structure 303 , thereby contacting first end 120 a with reference surface 405 of the other rear axle adjustment device 305 . The user may then read a second value indicated on indicator 110 representing a distance between reference surface 405 and reference surface 403 . If the second value is equal to zero, then the user may determine that the axle is properly aligned, and if the second value is not zero, the user may adjust rear axle adjustment device 305 until a value of zero is indicated when forward surface 233 is contacted with reference surface 403 and when first end 120 a is contacted with reference surface 405 .
[0035] Now referring to FIGS. 5 and 6 , motorcycle 500 according to an alternative design is shown. Motorcycle 500 preferably includes rear axle 501 , rear axle mounting structure 503 , rear axle adjustment device 505 , slot 507 , tire 520 , wheel 521 , and chain 510 . According to the alternative design, rear axle adjustment device 505 is arranged on a forward side of rear axle 501 , thus, reference surface 603 of rear axle mounting structure 503 is likewise disposed on a forward side of rear axle 501 . As will be understood by one skilled in the art, numerous similar alternative designs are possible, and use of gauge 100 according to the method described hereinabove is contemplated with motorcycles according to such similar alternative designs.
[0036] According to an alternative embodiment of the present invention, the housing of the gauge may include a bend, a flexible portion, or other modification which allows the probe to be contacted with the reference surface of the rear axle adjustment device and the forward surface of the housing to be contacted with the reference surface of the rear axle mounting structure more easily, and preferably without interference between other parts of the gauge, such as the indicator or casing, and other parts of the motorcycle. Such a modification may also preferably allow the user to more easily read the value indicated, or handle and maneuver the gauge.
[0037] Having, thus, described exemplary embodiments of the present invention, it should be noted by those skilled in the art that the within disclosures are exemplary only and that various other alternatives, adaptations, and modifications may be made within the scope and spirit of the present invention. Accordingly, the present invention is not limited to the specific embodiments as illustrated herein, but is only limited by the following claims. | A method and apparatus for alignment of a rear axle of a motorcycle, whereby measurement is made of the relative positions of each end of the axle with respect to the axle mounting structure, thereby reducing the time necessary for aligning the axle, and increasing the accuracy of the alignment. | 6 |
This application contains subject matter protected by copyright. All rights reserved.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates generally to network connection management and, in particular, to a flexible procedure for creating and managing persistent, secure connections to network directories and devices from a personal computer.
2. Description of the Related Art
It is known in the prior art to extend a network file system using a redirector. A known software redirector is the Server Message Block (“SMB”) (a/k/a the Common Internet File System or (“CIFS”)) redirector, which allows a user at a client machine to access various network devices located on servers in the network. Typically, such devices are of four (4) distinct types: file directories or drives, printers, modem/serial ports, and interprocess communication mechanisms (e.g., a named pipe). A user normally attaches to a given network network device after he or she logons to the network; conversely, the user normally detaches from a connected network device upon logoff, or upon logon as a different user.
In this conventional client-server network environment, certain key programs, such as persistent “services” and programmatic logon routines, typically cannot be located on network-attached drives. This is because logoff (as well as logon) on most or all network operating systems destroys all existing network connections (namely, the connections to network-attached drives, printers, named pipes and modems). In particular, logoff causes these programs to trap or fail, as the dynamic load libraries (dlls) and executable (.exe) files that are needed disappear with the lost network connection.
It is known in the art to provide so-called “persistent” connections in a network environment. Thus, for example, a remotely-booted computer (which may be diskless) often sets up a boot drive (e.g., via the IBM RIPL facility) as a persistent connection. This facility maintains a simple a security context (e.g., typically, the machine name) but does not “remember” the user's logon data. Likewise, known network operating systems (e.g., Novell Netware) provide an anonymous persistent connection for accessing a logon program. Like the previous example, however, this technique does not provide a flexible security context. A “security context” generally refers to that information which is necessary to authenticate a user to a server. In a simple case, it may include a userid and password. In more complex schemes, a security context may include or be defined by certificates (obtained through public key security techniques), tickets, information provided through a key exchange, or the like.
Moreover, such known approaches do not address persistent connections in the context of intermittent, transient network problems, i.e. problems that do not necessarily sever the network connection but that might otherwise interfere with it at some lower level signaling. Further, the existing state-of-the-art does not address persistent connection management in a simple and flexible manner, nor does it provide support for all four (4) types of network attached devices, namely, drives, printers, modems and named pipes.
The present invention addresses these needs.
BRIEF SUMMARY OF THE INVENTION
A network redirector is enhanced according to the present invention to provide a persistent connection management scheme exhibiting flexible security contexts, transparent reconnection upon transient network interruptions, simple setup and connection management, and support for all common network device types.
Persistent network connections created by the inventive mechanism survive logoff and persist across logon. A persistent connection is created when a network connection is established (or when an existing connection is modified) using a simple command line or GUI interface. Information supplied via the interface enables the mechanism to establish, dynamically, a different security context for each given persistent connection, and this security context is “flexible” in that it may differ from the user's logon id and password.
According to the invention, when a given connection to a network device is identified in a given manner as being persistent (e.g., by the setting of a “permanent” flag), several advantageous connectivity functions are provided. First, if the connection to the attached network device is severed, the invention reconnects that connection automatically with the appropriate security context. When the device becomes available, the user is not required to re-enter his or her userid and password, or to logon again. Second, if the connection to the attached device is interrupted transiently (but not severed), user is reconnected to the network device transparently (i.e. without requiring the user to take any action). Finally, where the user initiates standard logoff processing (that would otherwise unmount the device), the network connection is intentionally bypassed to prevent disconnection.
Preferably, the inventive mechanism is implemented within or as an adjunct to a network redirector supported on a client machine in a network. The client machine has a processor for executing an operating system having a network redirector or support for a redirection mechanism.
The foregoing has outlined some of the more pertinent objects and features of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention as will be described. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the following Detailed Description of the Preferred Embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and the advantages thereof, reference should be made to the following Detailed Description taken in connection with the accompanying drawings in which:
FIG. 1 is a simplified block diagram of a client-server network in which the present invention is implemented;
FIG. 2 is a block diagram of an SMB (CIFS) client structure that supports the network redirector and the persistent connections mechanism of the present invention;
FIG. 3 is a block diagram of the internal data structures used in the redirector mechanism of the present invention;
FIG. 4 is a simplified flowchart of a routine for setting up a persistent connection according to the present invention;
FIG. 5 is a simplified flowchart explaining how a user is transparently reconnected to a network device following an interruption on the connection; and
FIG. 6 is a flowchart illustrating how the present invention maintains persistent connection upon user logoff.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is implemented in a computer network 10 such as illustrated in FIG. 1 . In this network, a plurality of clients 12 are connected to one or more servers 14 . Each client is a personal computer or a diskless network computer. A given server preferably supports an operating system, such as IBM® OS/2® Warp™ Server Version 4.0. As is well-known, OS/2 Warp Server provides an application server foundation with integrated file and print sharing, backup and recovery services, remote business connections systems management, advanced printing, and Internet access. A given client machine has a processor that executes an operating system and various application programs. A representative client machine is a personal computer that is x86-, PowerPC®-, 68000- or RISC-based, that includes an operating system such as IBM® OS/2® Warp Client Version 4.0. Although the above operating systems are preferred, the present invention may be implemented on any network clients, including DOS, Windows 3.x, Windows NT Workstation, Windows for Workgroups and Windows '95.
As illustrated in FIG. 1, the client-server network includes a network file system 16 , e.g., an SMB (CIFS) file system. Other network file system types include NFS (for UNIX) and the like. As is well-known, a network client typically has support for a redirector 18 , which is software that allows a user at the client to access various network devices located on servers in the network. Typically, such devices are of four (4) distinct types: file directories or drives 20 , printers 22 , modem/serial ports 24 , and interprocess communication (“IPC”) mechanisms such as named pipes 26 . A user normally attaches to or mounts a given network network device after he or she logons to the network through the logon process 28 . Although the technique by which a network device is mounted is implementation-specific, typically this function is accomplished using a network device attachment/mount process 30 . The attachment process, among other things, attaches the user to the network device by issuing to the server certain connection requests. Conversely, the user normally detaches from a connected network device upon logoff, or upon logon as a different user. A logoff process 32 is used to demount network devices, typically by issuing to the redirector 18 certain disconnection requests.
FIG. 2 illustrates a known SMB (CIFS) client structure that is enhanced according to the present invention. This structure conforms to a conventional seven (7) layer network operating system architecture. The bottom layer of the stack is the physical layer 34 , comprising network adapters and MAC drivers. Moving upwards, the next layer 36 provides network transport services 38 (e.g., NETBEUI, TCP/IP, IPX, and the like). The next layer 40 includes the operating system kernel 42 together with the network redirector 44 (in this case, SMB/CIFS File System redirector (NETWKSTA.200)). The next layer 46 supports the network application programming interface (API) 48 (in this case, NETAPI.DLL) and the system API library 50 (in this case, DOSCALL1.DLL). The highest layer 52 is the network command line interface 54 (in this case, NET.EXE or some other graphical user interface).
According to the invention, the network API and command line utility are enhanced to add support for a “persistent connection” as a new device type modifier for network devices, namely, drives, printers, modems and named pipes. Moreover, a set of preferably standalone utilities is provided to manage the new connection type. The present invention also adds the ability to pass in a security context (userid/password to be used for the specific connection) to the API (or command line utility). Moreover, the invention enhances an exiting network drive reconnection logic to handle multiple security contexts. This allows transparent reconnection of network files and directories without loss of data in the event of temporary network failure of a transient, intermittent nature. Further, the invention enhances the network client file system (i.e. the redirector) to handle the new device type, multiple security contexts, and an internal interface to manage these constructs.
NET USE is an existing command that is used to attach a user to a network device. It is also supported in Windows '95, Windows '98 and Windows NT clients. According to the present invention, the new “persistent connection” device type modifier is specified via the NET USE command line interface (“CLI”), although one of ordinary skill will appreciate that this specification may be effected using a GUI or any other command interface.
The syntax of this command (as modified according to the present invention) is as follows:
NET USE [device|\\machineID\netname][/PERM [SERVER]]
NET USE device\\machineID/netname[password][/COMM][/PERM]
NET USE device alias [password][/COMM][/DOMAIN:name]
NET USE {device|\\machineID\netname}/DELETE
NET USE connects a requester to shared resources,
disconnects a requester from shared resources, or
displays information about network connections.
Typing NET USE without options lists the requester's
connections. The options of this command are:
NET USE
alias
A name that has been assigned to a shared
resource.
device
Assigns a name to connect to the resource.
There are three kinds of devices: disk
drives (A: through Z:), printer ports
(LPT1: through LPT9:), and serial device
ports (COM1: through COM9:).
\\machineID
Is the machine ID of the server
controlling the shares resource.
\netname
Is the name of the shared resources, or
netname.
password
Is the password for connecting to
resources on a server running share-level
security or on another domain where your
user ID is defined with a different
password. You can type an asterisk (*)
instead of the password to be prompted for
the password. The password will not be
displayed when you type it.
/COMM
Specifies that an LPT device is to be
connected to a serial device (non-spooled)
queue.
/DOMAIN:name
Allows connection to an alias on a domain
other than the logon domain.
/DELETE
Removes a network connection.
/PERM
Makes the connection permanent. The
connection is not deleted by LOGOFF, but
is deleted upon reboot.
/USER
Is the userid for connecting to resources
on a server on another domain where you
are defined with a different userid. This
is only valid when used with the /PERM
switch.
Referring now to FIG. 3, a block diagram is illustrated of the structures that are preferably created by the present invention to manage the persistent connections. According to the invention, whenever a user mounts a network device using the NET USE CLI described above, a per remote resource connection structure 56 (called con_list) is created. In addition, a per server session structure 58 (called srv_list) is created for each server to which the user is connected. There is one resource connection structure 56 for each network device connection, but only one server session structure 58 per server, irrespective of the number of client resource connection structures. Thus, as illustrated in FIG. 3, connection structures con_list1 and con_list2 are associated with session structure srv_list1, while connection structure con_list3 is associated with session structure srv_list2. This example, of course, is merely exemplary. These structures are mirrored on various servers in the network. As also seen in FIG. 3, the internal redirector structures include a global data structure 60 including the userid and password as well as alternative security information. According to the present invention, if the user enters an alternative security context in the “password” field of the NET USE CLI interface, such information may be used in lieu of the logon userid and password when a persistent connection is otherwise processed according to the present invention. Such alternative security context information is stored in the per server session strucure 58 and facilitates the provision of persistent connections with a “flexible” security context.
FIG. 4 is a flowchart of a routine for setting up and establishing a persistent connection according to the invention. The routine begins at step 62 with the user interactively entering the required information in the NET USE CLI. At step 64 , a test is performed to determine whether the /PERM modifier was selected. If not, the routine branches to step 66 and establishes a connection to the network device without reference to the present invention. If the outcome of the test at step 64 is positive, the routine continues at step 68 by making a call from the network CLI to the network API. This call validates the syntax of the flags passed in from the NET USE CLI. At step 70 , the network API invokes the network redirector. The routines then continues at step 72 to allocate the structures previously illustrated in FIG. 3 . The connection structure (con_list) maintains state information about the network device, and the session structure maintains state information with respect to the server to which the user is connecting.
The routine then continues to begin the process of mounting the user to the network device. The following steps are typically implementation-specific. At step 74 , the client's network transport services layer negotiates a protocol with the server. At step 76 , the client stack issues a session establishment request. This request includes a security context (e.g., the logon userid and password, or some other security context entered via the NET USE CLI). Thereafter, at step 78 , the client issues a tree connection request to the server to mount the network device. The server then validates the new network connection at step 80 .
Validation typically involves having the server verify that it has a device corresponding to the selected name, that the device is valid and, optionally, that the user has permission to attach to the device. At step 81 , the security context identified in the server's response (to the session establishment request) is stored in the session structure 58 , and the connection is flagged as “permanent” in the resource connection structure 56 . This completes the process.
FIG. 5 is a flowchart explaining how a user is transparently reconnected to a network device following an interruption of the network connection. The routine begins at step 90 with the user connected to the network device. At step 92 , the routine tests to determine whether the network connection has been interrupted. For example, such an interruption may occur at just a lower level of the network connection protocol (as a result of a transient, intermittent condition). An interruption may occur across the entire connection, due to a power failure, server failure, or the like. If the outcome of the test at step 92 is negative, the routine cycles. If, however, the outcome of the test at step 92 is positive, the routine continues at step 94 to reconnect the client to the server at the required protocol level. At step 96 , the routine passes to the redirector a security context that has been previously saved via the srv_list data structure. This enables the routine to reconnect without requiring the user to re-enter information defining that security context. Indeed, such reconnection is said to be “transparent” because it is effected without the user's awareness.
FIG. 6 is a flowchart illustrating how the present invention maintains persistent connection upon user logoff. The routine begins at step 98 with the user connected to the network device. At step 100 , the routine tests to determine whether the user has initiated a logoff. If the outcome of the test at step 100 is negative, the routine cycles. If, however, the outcome of the test at step 100 is positive, the routine continues at step 102 to issue tree disconnection requests for demounting the network devices. Step 102 , however, is not applied to the network connection that includes the /PERM flag setting. This, the connection is maintained.
Several extensions to the present invention are now described. Generally, the data structures identifying the persistent connections are stored in RAM in the client machine. One of ordinary skill will appreciate that these structures may be saved to disk such that when the machine is rebooted, the mechanism can reestablish the connections automatically prior to logon. In particular, the redirector reads the file and replays the connections with their appropriate security contexts.
Moreover, if desired, the CLI interface may require that the person seeking to add, delete or change a persistent connection evidence some local administrative authority prior to such operation.
The following is a representative data structure for the con_list data structure. The new /PERM flag is included:
/****CONNECT LIST
*
*
For each outstanding “use” or connection, one of
*
these structures is allocated
*
*/
struct
con_list {
struct con_list
*con_next;
/* ptr to next connection */
struct srv_list far
*con_pSrvLst;
/* ptr to srv_list for */
/* this connection */
unsigned short
con_SerialNum;
/* con list Serial Number */
unsigned short
con_ActiveCnt;
/* Num active references */
/* to this connection. */
unsigned short
con_DevUseCnt;
/* num explicit outstanding */
/* Device uses. */
unsigned short
con_UseCnt;
/* Total implicit and */
/* explicit Uses */
unsigned short
con_flags;
/* Status/Control flags */
unsigned short
con_DevType;
/* Device type (summary.api) */
/* used by Toon Protocol */
unsigned short
con_TreeId;
/* (SMB.Treeid) */
struct SrchBuf far
*con 1' pSrchBuf;
/* chain of search buffer(s) */
unsigned long
con_DormTime;
/* time con_list went dormant */
char
con_Text[CONTXTLEN];
/* remote name */
char
con_PassWd[PWLEN+1];
/* User Password */
short
con_PassWdLen;
/* User Password Length */
unsigned short
con_uid;
/* Validated uid ret by server */
unsigned short
con_ThrdId;
/* Thread ID of CON_INIT */
unsigned short
con_optsupp;
/* support optional search bit */
char
con_fs_type[FSLEN+1];
/* native fs of server share */
unsigned short
con_flags2;
/* @d02a More Status/Control
flags */
};
/* con_list */
/* connect_flags bits */
#define CON_INVALID
0x0001
/* connection is invalid */
#define CON_WAITING
0x0002
/* proc(s) waiting on con_list */
#define CON_DISCONNECTED
0x0004
/* con_list disconnected */
#define CON_BADPW
0x0008
/* Once good password is now bad
*/
#define CON_ZOMBIE
0x0010
/* con list being blasted away */
#define CON_NEEDTDIS
0x0040
/* Dormant connection - needs
discon*/
#define CON_RIPL
0x0080
/* It is a RIPL Connection */
#define CON_PERM
0x0100
/* User-defined “permanent” */
/* Connection */
#define CON-DFS
0x0200
/* “DFS” connection (reserved) */
#define CON_NEED_NULLOGOFF
0x1000
/* need null user log off */
#define CON_NULLUSR
0x4000
/* Null User Connection */
/****
WARNING:
Numerical value of CON_NULLUSR *MUST* equal that of RTCB_NULLUSR
*
and SRV_NULLUSR
*/
#define CON_INIT
0x8000
/* currently being initiated */
The following is a representative data structure for the srv_list data structure.
//****SRV_LIST
*
* Each session in the multiplexer has a srv_list
* entry. This structure is used to track the status
* of the session, the number of VCs in use, receives
* and receive requests on the session. Also
* maintained are the “NEGOTIATED” buffer limits on the
* given session, and the protocol being used.
*
*/
//****SRV_LIST
*
* Each session in the multiplexer has a srv_list
* entry. This structure is used to track the status
* of the session, the number of VCs in use, receives
* and receive requests on the session. Also
* maintained are the “NEGOTIATED” buffer limits on the
* given session, and the protocol being used.
*
*/
The present invention provides numerous advantages over the prior art. As has been described, the invention allows for the creation of persistent network connections that survive logoff and that, therefore, persist across logon. It allows a service daemon (e.g., NET.EXE) to modify an existing connection to a network device to make the connection “permanent”, thus preventing the connection's imminent destruction. Of course, if desired, the connection can be deleted explicitly.
The mechanism also enables the establishment of a security context for each particular persistent network connection that differs from the user's logged on user id and password. Further, the mechanism automatically reconnects these network connections (in the presence of network failure) with the correct security context. Moreover, the mechanism enables applications (such as service daemons) to have application specific security contexts (userid/password) that can be used to connect to their devices.
Another advantage of the present invention is that the network connections may be hidden from the standard NET USE service daemon list. If desired, the mechanism may limit the ability of a user to enumerate, add, delete or modify a persistent connection unless the user exhibits some local administrator authority. One of ordinary skill in the art also will appreciate that the invention may be extended to limit the ability of others (i.e. excepting the local administrator) from opening files or viewing data on a persistently-connected network drive.
As previously mentioned, the inventive persistent connections mechanism is implemented in software residing on the client machine. The inventive functionality is preferably implemented within or as an adjunct to a network redirector module of a network operating system. The given functions described above thus may be implemented as a set of instructions (program code) in a code module resident in the random access memory of the computer. Until executed by the computer's processor, the set of instructions may be stored in another computer memory, for example, in a hard disk drive, or in a removable memory such as an optical disk (for eventual use in a CD ROM) or floppy disk (for eventual use in a floppy disk drive), or downloaded via the Internet or other computer network.
In addition, although the various methods described are conveniently implemented in a general purpose computer selectively activated or reconfigured by software, one of ordinary skill in the art would also recognize that such methods may be carried out in hardware, in firmware, or in more specialized apparatus constructed to perform the required method steps.
As used herein, the term “server” should also be broadly construed to mean a computer, computer platform, an adjunct to a computer or platform, or any component thereof. Of course, a “client” should be broadly construed to mean one who requests or gets the file, and “server” is the entity which downloads the file.
Having thus described our invention, what we claim as new and desire to secure by letters patent is set forth in the following claims. | Persistent network connections created by the inventive mechanism survive logoff and persist across logon. A persistent connection is created when a network connection is established (or when an existing connection is modified) using a simple command line or GUI interface. Information supplied via the interface enables the mechanism to establish, dynamically, a different security context for each given persistent connection, and this security context is “flexible” in that it may differ from the user's logon id and password. If a user were currently authenticated for a given persistent network connection before a network failure, the user, upon connect, is allowed access to the network connection without requiring further authentication. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a novel amino group-containing diene copolymer. More particularly, it relates to an improvement in the resistance to growth of crack by solvent of an oil-resistant rubber typified by acrylonitrile-butadiene rubber (NBR).
2. Description of the Prior Art
In recent years, lead-free gasoline has been practically used as a countermeasure of the public pollution caused by lead in gas exhausted from cars. As a result, the amount of the aromatic component added to gasoline has been increased in order to improve the octane value. With an increase of the aromatic component content in gasoline, even concerning the oil-resistant performance of the rubber parts in a fuel system, the resistance to growth of crack by solvent has come to be required as a property important in practical use, in addition to performances such as low volume change, low decrease of strength, low decrease of elongation and the like after immersion, which have hitherto been required.
Hitherto, from the results of research on the effects of crosslinked structure of the vulcanized NBR, kinds and amounts of fillers and the like on the resistance to growth of crack by solvent of the vulcanized NBR in various kinds of solvents, it has been found that the resistance to growth of crack by solvent is not sufficiently imparted for practical use by only modifying the combination of ingredients and it has been considered that the improvement of the polymer itself is necessary. For this purpose, it has already been found that an effect is obtained by allowing the molecular weight distribution to have a peak on its low molecular weight side too, namely, have a double-peak-distribution, and by forming a blend of NBR with PVC.
SUMMARY OF THE INVENTION
As a result of extensive research on improvement of the resistance to growth of crack by solvent from the aspect of polymer structure, the present inventors have found that a multi-component copolymer formed by introducing into a conjugated diene-acrylonitrile copolymer a specific tertiary amino group-containing acrylate as the third monomer of the copolymer has improved resistance to oil and fuel oil particularly improved resistance to growth of crack by solvent and to swelling in a high aromatic solvent which maintaining the tensile strength, elongation, cold-resistance and other physical properties of the conjugated diene-acrylonitrile copolymer.
According to this invention, there is provided a novel amino group-containing diene copolymer comprising as the monomer units constituting the copolymer (A) 30 to 89.9 weight percent of butadiene, isoprene or both of them, (B) 10 to 50 weight percent of acrylonitrile and (C) 3.7 to 20 weight percent of a (meth)acrylate represented by the general formula (I): ##STR2## wherein R is H or CH 3 , R 1 and R 2 are independently alkyl groups having 2 to 8 carbon atoms, and X is an alkylene group having 2 to 4 carbon atoms.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows an infrared absorption spectrum of polymer A obtained in Examples 1 to 4.
DETAILED DESCRIPTION OF THE INVENTION
The amount of the bound butadiene and/or isoprene in the copolymer of this invention is 30 to 89.9 weight %, preferably 50 to 80 weight %. When it is less than 30 weight %, the cold resistance deteriorates greatly, while when it exceeds 89.9 weight %, sufficient oil-resistance cannot be obtained. The content of the bound acrylonitrile is 10 to 50 weight %, preferably 20 to 45 weight %. When it is less than 10 weight %, sufficient oil-resistance cannot be obtained, while when it exceeds 50 weight %, the cold resistance deteriorates greatly and the properties as an elastomer are imparied.
The (meth)acrylate of the constituent (C) of this invention is represented by the general formula (I): ##STR3## wherein R, R 1 , R 2 and X have the same meanings as defined above, and R is preferably CH 3 , and R 1 and R 2 are preferably alkyl groups having 2 to 4 carbon atoms.
When R 1 and R 2 in the (meth)acrylate of the general formula (I) are methyl groups, the resistance to growth of crack by solvent is improved but the other physical properties are not satisfactory, and particularly, the permanent compression set becomes great, so that it is undesirable from the viewpoint of physical properties of rubber. When hydrocarbon groups having 9 or more carbon atoms are used as the R 1 and R 2 , the improvement effect on the resistance to growth of crack by solvent is small, though no serious problems occur concerning physical properties of rubber.
The content of the bound (meth)acrylate (C) is 3.7 to 20 weight %, preferably 3.7 to 15 weight %. If the contnet is too small, the improvement effect on the resistance to growth of crack by solvent is small, while if the content exceeds 20 weight %, inconveniences appear in physical properties of rubber.
As the (meth)acrylate of the general formula (I), there may be used specifically diethylaminoethyl acrylate, diethylaminoethyl methacrylate, dibutylaminoethyl methacrylate, dibutylaminopropyl methacrylate, diethylaminobutyl methacrylate, dihexylaminoethyl methacrylate, dioctylaminoethyl methacrylate or the like.
The copolymer of this invention can easily be obtained by a usual emulsion polymerization process. As a polymerization initiator, there may be used a usual radical initiator such as a peroxide, a redox system catalyst, a persulfate or an azo compound. As an emulsifier, there may be used any of anionic, cationic, nonionic and amphoteric surfactants, or mixtures thereof. As a molecular weight modifier, there may be used mercaptans such as tertiary dodecyl mercaptan, normal dodecyl mercaptan and the like. The polymerization is conducted at a temperature of 0° to 50° C. in a reactor from which oxygen has been removed. The monomers, emulsifier, molecular weight modifier, initiator and other additives for polymerization may be added either in their whole amounts to the reaction system before the initiation of the reaction, or in portions after initiation of the reaction. Operation conditions such as temperature, stirring conditions and the like may be properly changed in the course of the reaction. The polymerization may be conducted either continuously or batchwise.
Although the molecular weight of the copolymer of this invention can be varied in a wide range, the Mooney viscosity ML 1+4 (100° C.) is usually in a range of 20 to 120, preferably in a range of 30 to 80. The copolymer of this invention is provided for practial use after compounded with usually used compounding agents such as fillers, anti-aging agents, plasticizers, stabilizers and the like. As the method of kneading with these compounding agents, there may be used various methods such as a usual roll kneading method, a kneading method by means of a closed type Banbury mixer, and the like. The compound may be molded and vulcanized in a usual way. That is to say, the compound may be either subjected to usual press-vulcanization or molded by means of an extruder and then vulcanized. The thus obtained vulcanizate is very excellent in resistance to growth of crack by solvent and resistance to swelling as compared with a conventional NBR or the like.
DESCRIPTION OF PREFERRED EMBODIMENTS
This invention is explained in more detail below referring to Examples. In Examples and Comparative Examples, parts and % are by weight unless otherwise specified.
EXAMPLES 1 TO 4 AND COMPARATIVE EXAMPLE 1
(Production of Copolymer)
Polymerization was conducted in an autoclave having a capacity of 20 liters by using the monomers and additives for polymerization mentioned below.
______________________________________Butadiene 43 partsAcrylonitrile 47 partsDiethylaminoethyl methacrylate 10 partsWater 220 partsSodium dodecylbenzenesulfonate 4 partst-Dodecyl mercaptan 0.55 partPotassium persulfate 0.27 partCyanoethylated diethanolamine 0.15 partPotassium hydroxide 0.10 part______________________________________
The polymerization reaction was stopped by adding hydroxylamine in a proportion of 0.2 part per 100 parts of the monomers to the reaction system when the polymerization conversion reached 70%. Subsequenlty, the resulting latex was subjected to steam distillation with heating to remove unreacted monomers. Thereafter, an anti-aging agent (an alkylated phenol (hindered phenol)) was added thereto in a proportion of 1 part per 100 parts of the produced polymer. The latex was coagulated with an aqueous calcium chloride solution to form a cram. The resulting cram was washed with water and dried in a vacuum at 60° C. to obtain a sample. As a result of nitrogen analysis and analysis by infrared absorption spectrum, the composition of the produced polymer was butadiene/acrylonitrile/diethylaminoethyl methacrylate=53/40/7, and the Mooney viscosity ML 1+4 (100° C.) was 52.0. The infrared absorption spectrum of this polymer (polymer A) is shown in FIG. 1.
Polymerization was carried out by use of the same recipe as in the production of polymer A, except that the monomer composition was varied as shown in Table 1. The compositions and Mooney viscosities of the various polymers produced are summarized in Table 2. The infrared absorption spectra of polymers B to D were the same as that in FIG. 1.
TABLE 1______________________________________ BD*.sup.1 AN*.sup.2 DEMA*.sup.3Kind of polymer (parts) (parts) (parts)______________________________________B 38 47 15C 48 47 5D 52 47 1E 53 47 0______________________________________ Note: *.sup.1 Butadiene *.sup.2 Acrylonitrile *.sup.3 Diethylaminoethyl methacrylate
TABLE 2______________________________________ CompositionKind of (BD/AN/DEMA) Mooney viscositypolymer (weight ratio) ML.sub.1+4 (100° C.)______________________________________B 49/40/11 61.0C 57.3/39/3.7 57.5D 59.4/40/0.6 49.5E 59/41/0 55.0______________________________________
(Evaluation of Valcanizate)
The polymer obtained as mentioned above was kneaded with the compounding recipe mentioned below by means of a roll to form a sheet, which was then press-valcanized at 150° C. for 30 minutes to obtain a sheet having a thickness of 2 mm, which was provided for measurement of physical properties. The measurement of the physical properties was conducted according to the following methods:
______________________________________Compounding Recipe______________________________________Polymer 100FEF (fast extrusion furnace, a kind of 40carbon black)ZnO 5Stearic acid 1DOP 5S 1.2TS (tetramethylthiuram monosulfide) 0.4DM (dibenzothiazyl disulfide) 1.0______________________________________ Methods for measuring physical properties:
(I) Tensile test: JIS K 6301
(II) Hardness test: JIS K 6301 (JIS A-type)
(III) Gasoline resistance: JIS K 6301
A sample is immersed in a fuel oil (Fuel D) at 40° C. for 48 hours.
(IV) Parmanent compression set: JIS K 6301, 100° C.×22 hours
(V) Low temperature test: JIS K 6301, Gehman torsional test
(VI) Resistance to growth of crack by solvent: On a No. 1 dubbell specimen, index lines are drawn at intervals of 10 mm, and at the center of space between the index lines a crack of 2 mm is provided parallel to the index lines to thrust through the specimen to the back side. The specimen is then stretched so that the stretching ratio becomes 100%. The specimen in the stretched state is immersed in Fuel D at 40° C. and the time required till breaking is measured.
The results of the tests are summarized in Table 3. It is seen that when the DEMA content is increased, the resistance to growth of crack by solvent and resistance to swelling are greatly improved, and other physical properties of rubber are hardly affected. From these results, it is obvious that the copolymer of this invention is greatly effective for improving the resistance to growth of crack by solvent.
TABLE 3__________________________________________________________________________ Comparative Example Example Example Example Example 1 1 2 3 4Kind of polymer E D C A B__________________________________________________________________________Bound DEMA content (%) 0 0.6 3.7 7.0 11.0Physical properties in normal stateT.sub.B (kgf/cm.sup.2) 236 230 220 215 205E.sub.B (%) 560 560 580 600 610Hs (JIS-A) 69 70 69 68 68Permanent compression set (%) 22.0 22.0 23.0 24.0 25.0(100° C. × 22 hrs)Immersion test (Fuel D,40° C. × 48 hrs)Sc (T.sub.B) (%) -58 -54 -42 -38 -36Sc (E.sub.B) (%) -51 -48 -39 -36 -33CH (Point) -24 -22 -22 -22 -22ΔV (%) +46 +40 +35 +31 +30Resistance to growth of crack by 65 102 150 210 230solvent (Fuel D, 40° C., 100%stretching)Gehman torsional testT.sub.10 (°C.) -14.5 -14.0 -13.5 -13.0 -12.0T.sub.100 (°C.) -19.0 -19.0 -18.5 -18.0 -17.0__________________________________________________________________________ Note: Sc (T.sub.B) refers to percentage of change in tensile strength at break after immersion. Sc (E.sub.B) refers to percentage of change in elongation at break after immersion. CH refers to change of hardness after immersion. ΔV refers to percentage of change of volume.
COMPARATIVE EXAMPLES 3 AND 3
Polymerization was conducted in the same manner as in the case of polymer A, except that dimethylaminoethyl methacrylate and dodecylaminoethyl methacrylate were substituted for the acrylate of this invention to produce polymers F and G, respectively. Each polymer was kneaded and vulcanized with the same recipe under the same conditions as in Example 3. Physical properties of the resulting vulcanizates were then evaluated in the same manner as in Example 1. The results are summarized in Table 4.
TABLE 4__________________________________________________________________________ Comparative Comparative Example 3 Example 2 Example 3Kind of polymer A F G__________________________________________________________________________Bound AN content (%) 40 41 41Bound methacrylate content (%) 7 7 7ML.sub.1+4 (100° C.) 52.0 50.0 57.0Physical properties in normal stateT.sub.B (kgf/cm.sup.2) 215 223 214E.sub.B (%) 600 620 580Hs (JIS-A) 68 67 70Permanent compression set (%) 24.0 31.0 25.0100° C. × 22 hrsImmersion test (Fuel D, 40° C. × 48 hr)Sc (T.sub.B) (%) -38 -35 -39Sc (E.sub.B) (%) -36 -34 -40CH (Point) -22 -22 -24ΔV (%) +31 +32 +43Resistance to growth of crack by solvent 210 206 71(Fuel D 40° C., 100% stretching)Gehman torsional testT.sub.10 (°C.) -13.0 -13.0 -13.5T.sub.100 (°C.) -18.0 -17.5 -19.0__________________________________________________________________________ Note: Sc (T.sub.B), Sc (E.sub.B), CH and ΔV have the same meanings as in Table 3.
From the results shown in Table 4, it is understood that when R 1 and R 2 of the (meth)acrylate represented by the general formula (I) are methyl groups, the permanent compression set is increased as shown in Comparative Example 2, and when the R 1 and R 2 are dodecyl groups, the resistance to growth of crack by solvent is not improved as shown in Comparative Example 3.
EXAMPLES 5 TO 10 AND COMPARATIVE EXAMPLES 4 AND 5
Various polymers having the compositions shown in Table 5 were produced by using diethylaminoethyl acrylate (Example 5), dibutylaminoethyl methacrylate (Example 6), dihexylaminoethyl methacrylate (Example 9) or dioctylaminoethyl methacrylate (Example 10) instead of the diethylaminoethyl methacrylate in Examples 1 to 4 and Comparative Example 1, or by using isoprene (Examples 7 and 8, Comparative Examples 4 and 5) instead of the butadiene in Examples 1 to 4 and Comparative Example 1, and subjected to the same procedure as in the cases of polymers A to E. Each polymer was kneaded and vulcanized with the same recipe under the same conditions as in Example 1. Physical properties of the resulting vulcanizates were then evaluated in the same manner as in Example 1. The results obtained are summarized in Table 5. The infrared absorption spectra of polymers H, I, J, K, N and O were substantially the same as that in FIG. 1.
TABLE 5__________________________________________________________________________ Example Example Example Example Comparative Comparative Example Example 5 6 7 8 Example 4 Example 5 9 10Kind of polymer H I J K L M N O__________________________________________________________________________Polymer compositionBD 53 55 -- -- -- -- 53 53AN 40 39 31 25 32 25 40 41IP -- -- 62 69 68 75 -- --DEMA -- -- 7 6 -- -- -- --DEAA 7 -- -- -- -- -- -- --DBMA -- 6 -- -- -- -- -- --DHMA -- -- -- -- -- -- 7 --DOMA -- -- -- -- -- -- -- 6ML.sub.1+4 (100° C.) 58.5 62.0 70.0 98.0 76.0 110 53.5 48.0Physical properties in normal stateT.sub. B (kgf/cm.sup.2) 205 203 146 168 152 176 198 196E.sub.B (%) 630 640 790 780 780 740 650 660Hs (JIS-A) 66 68 60 67 61 66 21 20Permanent compression set 26 22 35 30 36 31 23 22(100° C. × 22 hrs)Immersion test (Fuel D, 40° C. ×48 hrs)Sc (T.sub.B) (%) -35 -37 -70 -76 -83 -90 -36 -37Sc (E.sub.B) (%) -30 -39 -53 -63 -68 -76 -40 -38CH (Point) -21 -24 -29 -31 -32 -34 -25 -27ΔV (%) +30 +35 +45 +52 +57 +68 +37 +38Resistance to growth of crack by 218 178 53 24 10 2 172 163solvent (sec)(Fuel D, 40° C., 100% stretching)Gehman torsional testT.sub.10 (°C.) -14.0 -12.5 -8.0 -21.0 -7.5 -20.0 -14 -15T.sub.100 (°C.) -19.0 - 17.0 -13.0 -28.0 -14.0 -29.0 -18 -19.5__________________________________________________________________________ NOTE: IP: Isoprene DEMA: Diethylaminoethyl methacrylate DEAA: Diethylaminoethyl acrylate DBMA: Dibutylaminoethyl methacrylate DHMA: Dihexylaminoethyl methacrylate DOMA: Dioctylaminoethyl methacrylate Sc (T.sub.B), Sc (E.sub.B), CH and ΔV have the same meanings as in Table 3. | zs An amino group-containing copolymer which is composed of (A) butadiene, isoprene or both of them, (B) acrylonitrile and (C) a (meth)acrylate represented by the general formula (I): ##STR1## wherein R is H or CH 3 , R 1 and R 2 are independently alkyl groups having 2 to 8 carbon atoms, and X is an alkylene group having 2 to 4 carbon atoms, and has a polymer composition (weight %) of (A):(B):(C) of 30 to 89.9:10 to 50:0.1 to 20. Said multi-component copolymer is used as oil-resistant rubber, and is particularly excellent in resistance to growth of crack by solvent. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a silicone bag assembly for use in pharmaceutical manufacturing and for holding health care related solutions and, more particularly, to apparatus for manufacturing such a bag assembly.
At the present time, virtually all bags used by the pharmaceutical industry and for holding health care related solutions (such as intravenous bags) are manufactured of polyvinyl chloride (PVC). PVC is a commonly used inexpensive plastic material which is naturally hard. To soften such material so that it can be used as a flexible bag and as flexible tubing, plasticizers such as phthalate esters are added to the PVC to soften it. Recently there has been concern that phthalates may leach from the PVC to which they have been added, thereby contaminating aqueous fluids held in PVC bags and traveling through PVC tubing. Since PVC bags are used to store intravenous solutions and blood for transfusions, phthalates which leach from the PVC are infused directly into a patient's bloodstream. It has therefore been proposed to form the bag and tubing from silicone, which does not react with contacting liquids or leach chemicals into contacting liquids. Accordingly, a need exists for apparatus capable of manufacturing such a bag assembly, particularly in a continuous production process.
SUMMARY OF THE INVENTION
According to the present invention, the bag assembly is formed from a tube and a tubular flexible membrane with opposed open ends. The basic inventive apparatus includes a base for supporting the membrane and the tube with the tube extending into one of the membrane open ends, a first clamp adapted to flatten and clamp the membrane to itself and to the tube along a line spaced from and substantially parallel to the open end, an injector adapted to inject liquid adhesive into the open end and around the tube between the open end and the line, and a second clamp adapted to flatten and clamp the membrane to itself and to the tube between the line and the open end. Accordingly, the first clamp is operative to prevent injected adhesive from getting into the interior of the tubular membrane.
Using the aforedescribed basic apparatus, a continuous production manufacturing apparatus is provided including a pair of endless belt systems arranged for movement in opposite angular directions. The first belt system includes a plurality of bases mounted thereon at a plurality of equally spaced locations. The second belt system has mounted thereon a plurality of the first and second clamps and is dimensioned to expose a leading portion of the first endless belt system. The clamps are arranged so that each first clamp is spring coupled to the second endless belt system so as to be yieldably biased away from the second endless belt system. The clamps are arranged so that the first clamp contacts a respective base before the second clamp contacts that base. A membrane placement station is arranged to place a respective flexible membrane on each base while that base is exposed, and a tube insertion station is arranged to insert a tube into such a placed membrane. An adhesive injection station is arranged to inject liquid adhesive into the open end of each membrane while on its respective base with a respective tube inserted therein while a first clamp contacts the membrane but before a second clamp contacts the membrane. After the second clamp contacts the membrane, the clamped assembly cures while travelling along the belt systems. The clamps later separate from the bag assembly, which falls off the trailing end of the first endless belt system.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing will be more readily apparent upon reading the following description in conjunction with the drawings in which like elements in different figures thereof are identified by the same reference numeral and wherein:
FIG. 1 is a perspective view of a bag assembly which may be produced by apparatus constructed according to the present invention;
FIG. 2 is a perspective view of a manually operated apparatus according to the present invention;
FIGS. 3-5 schematically depict steps in the formation of a bag assembly using the apparatus shown in FIG. 2 according to this invention;
FIG. 6 is a schematic perspective view showing continuous production manufacturing apparatus according to the present invention;
FIG. 7 is a perspective view showing a clamp assembly for use in the apparatus shown in FIG. 6 according to the present invention;
FIG. 8 is an end view of the clamp assembly shown in FIG. 7 with the first clamp member contacting the base;
FIG. 9 is an end view of the clamp assembly shown in FIG. 7 with both clamp members contacting the base;
FIG. 10 is a perspective view of an illustrative adhesive injection head; and
FIG. 11 illustrates the path taken by the adhesive injection head shown in FIG. 10 .
DETAILED DESCRIPTION
Referring now to the drawings, FIG. 1 shows an illustrative bag assembly, designated generally by the reference numeral 20 , which includes a flexible silicone membrane 22 which is formed as a seamless thin-walled tube having opposed ends 24 , 26 . The bag assembly 20 further includes a pair of silicone tubes 28 , 30 inserted into the ends 24 , 26 , respectively. Each of the tubes 28 , 30 is terminated by a flange and has a stainless steel backup cup slidably mounted thereon, which do not form a part of the present invention. In any event, each of the ends 24 , 26 is flattened and sealed to itself and to a respective one of the tubes 28 , 30 , as by adhesive or the like.
Apparatus for manually forming a bag assembly 20 is shown in FIG. 2 . As shown, the apparatus includes a base 32 adapted to support the membrane 22 and the tubes 28 , 30 . Accordingly, the base 32 is formed with a groove 34 sized to accommodate the tubes 28 , 30 therein. Mounted to the base 32 are a pair of first clamps 36 which are pivotally mounted at one end and are held down by holders 38 . Each first clamp 36 has a groove 40 which is aligned with the groove 34 when the first clamp 36 is in contact with the base 32 . A pair of second clamps 42 are also provided. The second clamps 42 are provided with bores (not shown) into which the posts 44 are inserted to provide an appropriate alignment for the clamps 42 . The clamps 42 are each formed with a groove 46 which is aligned with the groove 34 when the clamps 42 are lowered on the posts 44 .
FIGS. 3-5 schematically depict the steps for forming a bag assembly using the apparatus shown in FIG. 2 . Thus, as shown in FIG. 3, initially a tubular membrane 22 is placed on the base 32 and the tubes 28 , 30 are inserted into the open ends 24 , 26 , respectively, of the membrane 22 . Next, the clamps 36 are pressed down over the membrane 22 and the tubes 28 , 30 so as to flatten and clamp the membrane 22 to itself and to the tubes 28 , 30 along lines spaced from and substantially parallel to the open ends 24 , 26 . Adhesive injectors 48 have their heads inserted into the open ends 24 , 26 to inject liquid adhesive, preferably liquid silicone when the membrane 22 and the tubes 28 , 30 are formed of silicone, into the open ends 24 , 26 and around the tubes 28 , 30 between the open ends and the aforedescribed clamp lines. Thus, the clamps 36 prevent adhesive from entering the interior of the tubular membrane 22 . Next, as shown in FIG. 5, the clamps 42 are put in place and the entire assembly is heated to cure the adhesive. When the clamps 36 , 42 are removed, the bag assembly including the membrane 22 and the tubes 28 , 30 may be removed from the base 32 .
FIGS. 6-11 illustrate different aspects of a continuous production manufacturing apparatus, designated generally by the reference numeral 50 , for manufacturing the bag assembly shown in FIG. 1 . The apparatus 50 includes a first endless belt system 52 and a second endless belt system 54 . As shown, the first endless belt system 52 is longer than the second endless belt system 54 so as to leave exposed a leading portion of the first endless belt system 52 which immediately precedes that portion of the first endless belt system 52 which is overlain by the second endless belt system 54 . Thus, the first endless belt system 52 includes a belt 56 formed into a continuous loop around drive rollers 58 . It is understood that there are other support rollers intermediate the drive rollers 58 , but for purposes of clarity the intermediate support rollers are not shown. Secured to the belt 56 , at a plurality of equally spaced locations, are a plurality of base members 60 . Each of the base members 60 is substantially the same as the base 32 (FIG. 2 ), but without the clamps 36 , the holders 38 and the posts 44 . In addition, each of the base members is provided with one or more heater cartridges 62 . The base members 60 are formed of a heat conducting material so that the heater cartridges 62 maintain the surface temperature of the base members 60 at a temperature in the range from about 150° F. to about 400° F., preferably about 300° F.
The second endless belt system 54 includes a belt 64 formed into an endless loop around drive rollers 66 . Again, for purposes of clarity, intermediate support rollers have not been shown. The drive rollers 66 are arranged to rotate oppositely to the drive rollers 58 so that the belts 56 , 64 move in opposite angular directions, as shown by the directional arrows. Mounted to the belt 64 at a plurality of equally spaced locations, with the same spacing as the base members 60 , are a plurality of clamp fixtures 68 . Preferably, there is a plurality of clamp fixtures 68 along each longitudinal edge of the belt 64 , so that bag assemblies with tubes at opposite ends can be fabricated. As best shown in FIG. 7, each clamp fixture 68 includes a first clamp block 70 and a second clamp block 72 . The second clamp block 72 is secured to the belt 64 and is generally rectilinear with an L-shaped cross section when viewed orthogonally to its direction of travel along the second endless belt system 54 , as best seen in FIGS. 8 and 9. The first clamp block 70 is generally rectilinear and is sized to fit within the opening of the L-shape of the second clamp block 72 . The first clamp block 70 is spring coupled to the second clamp block 72 , as by posts 74 within the interior of compression springs 76 . Thus, the first clamp blocks 70 are yieldably biased out of the L-shape openings of the second clamp blocks 72 in a direction away from the belt 64 . Further, the clamp blocks 70 , 72 are formed of a heat conducting material and have heater cartridges 78 , 80 , respectively, which maintain the surface temperature of the blocks 70 , 72 the same as that of the base members 60 .
As shown in FIG. 6, as a clamp fixture 68 comes down around the right side of the second endless belt system 54 , the first clamp block 70 initially contacts a respective base member 60 , also shown in FIG. 8 . As the clamp fixture 68 moves to the left, the second clamp block 70 approaches the base member 60 and the first clamp block 70 is moved into the L-shape opening of the second clamp block 72 against the force of the spring 76 . When the second clamp block 72 contacts the base 60 , as shown in FIG. 9, both the first and second clamp blocks 70 , 72 are in contact with the base member 60 .
The apparatus 50 also includes a membrane placement station 78 adjacent the exposed portion of the first endless belt system 52 . The membrane placement station 78 is arranged to take a length of tubular flexible membrane 80 , illustratively cut from a supply 82 of tubular flexible silicone membrane, and place that length 80 on an adjacent base member 60 . At a downstream location along the first endless belt system 52 is a tube insertion station 84 arranged to insert a length of tube 86 into an open end of a membrane 80 on a base member 60 while that base member 60 is still within the exposed portion of the first endless belt system 52 . Illustratively, there is a tube insertion station 84 on each side of the belt system 52 and the tube 86 is illustratively Sani-Tech® 45 or Tygon® tubing manufactured by Norton Performance Plastics Corporation of Sparta, N.J.
Downstream from the tube insertion station is an adhesive injection station 88 . The adhesive injection station 88 is arranged to inject liquid adhesive into the open end of the membrane 80 after a first clamp block 70 engages the membrane 80 but before the second clamp block 72 engages the membrane 80 . Exemplary adhesive is Sani-Tech® 45 or 70 LIM silicone adhesive, manufactured by Norton Performance Plastics Corporation of Sparta, N.J. Illustratively, there is an adhesive injection station 88 on each side of the belt system 52 . The adhesive injection station 88 includes an injection head which illustratively is of the form shown in FIG. 10 and designated generally by the reference numeral 92 . The head 92 is bifurcated with a gap 94 for receiving a tube 86 . Illustratively, the injection station 88 is arranged to cause the head 92 to move along the closed path shown in FIG. 11 . Thus, from the initial location 96 , the head 92 is caused to move downwardly as shown by the arrow 98 and then inwardly to extend into an open end of a membrane 80 , as shown by the arrow 100 , with the tube 86 being received within the gap 94 . Next, the head 92 moves laterally as indicated by the arrow 102 , following the movement of the membrane 80 . During this travel, liquid adhesive is injected into the open end of the membrane 80 through the slots 104 of the head 92 . The clamp block 70 prevents the adhesive from reaching the interior of the tubular membrane 80 . Next, the head 92 is moved outwardly from the open end of the membrane 80 , as indicated by the arrow 106 , then upwardly, as indicated by the arrow 108 , and finally laterally in the direction opposite to the direction of travel of the membrane 80 , as indicated by the arrow 110 , back to the initial location 96 .
After liquid adhesive is injected into the open end of the membrane 80 , the second clamp block 72 contacts the membrane 80 . It will be recalled that the base members 60 and the clamp blocks 70 , 72 are all heated. Thus, as the membrane 80 with the tube 86 and the liquid adhesive travels along the apparatus 50 , the heat applied by the base member 60 and the clamp blocks 70 , 72 cures the adhesive. When the membrane and tube assembly reaches the leftmost end of the belt system 52 , the clamp blocks 70 , 72 disengage therefrom and the membrane and tube assembly falls off the end of the belt system 52 into a receptacle (not shown) provided therefor.
The assembly 20 can be constructed to have any desired capacity. As presently contemplated, the capacity will probably be in the range from about 750 ml up to about 5 liters, but larger capacity assemblies, even up to one thousand liters, are within the scope of this invention. Further, the assembly 20 is not limited to any specific use, although it is presently contemplated that it will be used for storage (and cryogenic shipment) of intermediate or concentrated drug products during manufacture in an industrial setting.
The aforedescribed inventive apparatus results in a number of manufacturing advantages. Thus, stock items of tubing and tubular membranes can be utilized. Also, it is economically advantageous to only adhesive weld the two ends of the bag, instead of having to perform a full perimeter adhesive weld. Further, the clamp design leaves the diameter of the tubing intact while insuring a good seal between the tubing and the membrane. Additionally, an all silicone (including adhesive) product is produced.
Accordingly, there has been disclosed improved apparatus for forming a bag assembly. While illustrative embodiments of the present invention have been disclosed herein, it will be understood that various adaptations and modifications to the disclosed embodiments are possible, and it is intended that this invention be limited only by the scope of the appended claims. | Apparatus for forming a bag assembly from a tube and a tubular flexible membrane operates in accordance with a four step process. This process includes the steps of clamping the tube within an open end of the membrane, injecting liquid adhesive into the open end of the membrane, clamping the membrane and tube where the adhesive was injected, and heating and curing the assembly. | 1 |
[0001] This invention claims the benefit of priority based on the U.S. Provisional Application Ser. No. 60/547,991 filed Feb. 26, 2004.
FIELD OF THE INVENTION
[0002] This invention relates to an antimicrobial agent and in particular to a composition of matter, a method of making and using the composition of matter for antimicrobial, anti-bacterial, pre-harvest and post harvest treatment of foodstuffs to inhibit cellular growth of known pathogenic, indicator and spoilage organisms that contaminate the human food chain.
BACKGROUND AND PRIOR ART
[0003] Protein sources in the human food chain, such as, eggs, raw meats, poultry, game birds, milk and dairy products, fish, shrimp, frog legs, and the like, carry the potential for nourishment and the potential for illness and death. Edible vegetation in the human diet, such as fruit, vegetables, and crops harvested and handled in contaminated environments can also carry the potential for illness and death. Well-known pathogens such as salmonella, listeria and e - coli , as well as indicator and spoilage organisms, including staph bacteria can be found prior and during the processing or harvesting of raw meats, fruit, vegetables or in partially cooked foodstuffs and animal products consumed by humans.
[0004] The globalization of business, travel and communication brings increased attention to worldwide exchanges between communities and countries, including the potential globalization of the bacterial ecosystem. Harmful bacteria were once controlled with antibiotics, such as penicillin, in the mid-1940s; but the control no longer exists as more and more antibiotic resistant bacteria appear around the globe. For example, before 1946 about 90 percent of Staphylococcus aureus isolates in hospitals were susceptible to penicillin, by 1952, 75 percent of isolates were penicillin-resistant. Bacterial resistance to antimicrobial agents has emerged, throughout the world, as one of the major threats both in human and veterinary medicine. Resistance to antibiotics and antimicrobial agents has emerged at an alarming rate because of a variety of factors, such as clustering and overcrowding, the use of antibiotics in animal culture and aquaculture, an increase in the number of elderly people, increased traveling, the sale of antibiotics over the counter, self-treatment with antibiotics, a lack of resources for infection control, and the inappropriate use of antibiotics.
[0005] Thus, the world population is at increased risk for acquiring antimicrobial-resistant foodborne infections. Even a small increase in the prevalence of resistance in the most significant pathogenic bacteria may lead to large increases in the potential for treatment failures and other adverse outcomes, including death.
[0006] Appropriate use of antimicrobial agents in humans and food animals is necessary to maintain the antimicrobial effectiveness and reduce the potential for the spread of resistant organisms. While therapeutic usage of antimicrobial agents in food animals is important to promote animal health and provide an affordable supply of meat, milk, and eggs, it is vital that the long-term effectiveness of antimicrobial agents used in human medicine be preserved. The present invention provides an antimicrobial processing aid and food additive for which there is no known resistance and can be used to protect public health.
[0007] In U.S. Pat. Nos. 5,989,595 and 6,242,011 B1 to Cummins, an acidic composition of matter is disclosed that is useful for destroying microorganisms that spoil food, such as fish. The composition of matter, patented by Cummins, is also useful for skin treatment of melanoma and the treatment of other bacteria, and serves as the precursor for the novel antimicrobial agent of the present invention.
[0008] U.S. Pat. No. 5,997,911 to Brinton et al. describe that a simple copper salt, hydroxycarboxylic acid and a buffering agent such as ammonium salts can be solubilized in drinking water for turkeys and swine in an antidiarrheal effective dosage.
[0009] U.S. Pat. No. 6,506,737 B1 to Hei et al. describe an antimicrobial composition for the food industry that may include sulfuric acid, sulfates and an ammonium halide salt to provide a gel-thickened compound for cleaning and sanitizing surfaces among other uses. The use of a halide ingredient limits usage for ingestion by man or animals and would be deleterious to machinery, plants and other vegetation.
[0010] U.S. Pat. No. 6,565,893 B1 to Jones et al. describe an aqueous disinfectant for swimming pools and the like, wherein copper sulfate pentahydrate, water, sulfuric acid and ammonium sulfate are combined in a “cold process” requiring that the formulation be maintained at a temperature above 40° F. to keep metallic ions in suspension.
[0011] U.S. Patent Pub. No. 2003/0118705 A1 to Cook et al. describe an ingestible disinfectant to eradicate and control pathogens on plants, animals, humans, byproducts of plants and animals and articles infected with pathogens; the disinfectant includes sulfuric acid, water and metallic ions, particularly copper, silver and gold.
[0012] Collectively, the above documents do not provide a halogen-free composition of matter that is stable under a wide range of temperatures and pH ranges, ingestible, and effective in both pre-harvest and post-harvest treatment of foodstuffs consumed by man and other animals. The composition of the present invention is safe and effective in an unlimited number of pre-harvest and post-harvest applications and is also safe for the environment.
SUMMARY OF THE INVENTION
[0013] The first objective of the present invention is to provide a composition of matter and method for its production that inhibits cellular growth of pathogenic organisms.
[0014] The second objective of the present invention is to provide a composition of matter and method for its production that inhibits cellular growth of indicator and spoilage organisms.
[0015] The third objective of the present invention is to provide a compositon of matter and method for its production, for use in scalding tank waters for dipping poultry and other animal carcasses.
[0016] The fourth objective of the present invention is to provide a composition of matter and method for its production, for use in water treatment processes in a meat production line, including, but not limited to, the spray bath, final rinse and chill water tank.
[0017] The fifth objective of the present invention is to provide a composition of matter and method for its production, for the treatment of wastewater.
[0018] The sixth objective of the present invention is to provide a compositon of matter and method for its production, for the treatment of animal feed and water.
[0019] The seventh objective of the present invention is to provide a composition of matter and method for its production, that can be used against a wide range of human, plant and animal diseases as well as minimize the growth and spread of diseases in plants and plant surfaces, either pre-harvest or post harvest.
[0020] The eighth objective of the present invention is to provide a composition of matter that is used as a surface disinfectant for hospitals, homes and other areas that require hard surface disinfectants.
[0021] The ninth objective of the present invention is to provide a composition of matter that inhibits the growth of pathogenic, indicator and spoilage bacteria that have become antibiotic resistant.
[0022] The tenth objective of the present invention is to provide a composition of matter for use in icemakers, so that ice used in post-harvest processing of foodstuff can perform an additional antimicrobial function.
[0023] Another objective of the present invention is to provide an antimicrobial aid to reduce microbial contamination in food items such as milk, poultry, eggs, red meat, meat from pigs, and seafood either pre-harvest, post-harvest, during and after processing.
[0024] Further objects and advantages of this invention will be apparent from the following detailed description of a presently preferred embodiment, which is illustrated in the accompanying tables and graphs.
BRIEF DESCRIPTION OF THE FIGURES
[0025] FIG. 1 is a graph showing the effect of PHB0020 on pathogenic and spoilage bacterial isolates exposed for 2 minutes.
[0026] FIG. 2 is a graph showing the logarithm of reductions in bacterial colony levels.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] Before explaining the disclosed embodiment 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.
[0028] It would be useful to discuss the meanings of some words used herein and their applications before discussing the composition of matter and method of using and making the same:
Pre-harvest—is used herein to mean any time after birth or seed germination and before the cessation of growth and life of a plant or animal. Post-harvest—refers to any time after the cessation of growth and life of a plant or animal and includes non-food hard surfaces involved in processing and preparing foodstuffs. PHB0020—Copper sulfate pentahydrate and/or other forms of copper ions, and silver sulfate and/or other forms of silver ions added to pHarlo for the antimicrobial, anti-bacterial additive of the present invention. PHB0028—the formulation to be used as an additive in animal feed. PHBO128—the formulation for use as an additive to treat wastewater. pHarlo—composition of matter claimed in U.S. Pat. Nos. 5,989,595 and 6,242,001 B1 to Cummins and incorporated herein by reference and more completely described below. E - coli—Escherichia coli , indicator bacteria Listeria—Listeria monocytogenes , a pathogen Pseudomonas—Pseudomonas fluorescens , spoilage bacteria Salmonella—Salmonella typhimurium , a pathogen Shewanella—Shewanella putrefaciens , spoilage bacteria Staph—Staphylococcus aureus , a pathogen
[0041] The acidic composition of matter and method of making are similar to that described in U.S. Pat. Nos. 5,989,595 and 6,242,011 B1 to Cummins and are incorporated herein by reference.
[0042] First, a pressurized vessel is selected that includes a cooling jacket and no electrode attachments; however, the preferred pressurized vessel is fitted with two electrodes, a cathode and anode, to provide a direct current (DC) voltage 1 ft. above the bottom of the container. The electrodes are spaced approximately three (3) feet apart.
[0043] The processing steps of the present invention comprise combining sulfuric acid with purity in a range from approximately 94% to approximately 99.9%, in a 1 to 2 volume ratio with distilled water and ammonium sulfate in a ratio of 2.77 pounds of ammonium sulfate per gallon of distilled water to provide mixture (I). The mixture (I) is combined in the pressurized vessel having preferably two strategically placed electrodes, a cathode and anode. During the addition of ammonium sulfate, a direct current (DC) voltage is applied to the mixture. The voltage is applied in a range from approximately one (1) amp to approximately 100 amps, preferably between approximately 1 amp and approximately 5 amps. The mixture is then heated under pressure in a range of from approximately 1 pound per square inch (psi) to approximately 15 psi above atmospheric pressure. Heating of the mixture is in a range of from approximately 200° Fahrenheit (F.) to approximately 1200° F., preferably from approximately 800° F. to approximately 900° F. for approximately 30 minutes. With the application of heat and pressure as specified above, it is understood by persons skilled in the art, that a judicious selection of temperature, time and pressure is required and should be adjusted to maintain a safe chemical reaction.
[0044] After cooling the mixture, a stabilizer is added. The stabilizer is a portion of mixture (I) prior to heating in the pressure vessel. The quantity of stabilizer used is approximately 10 weight percent of the total weight of mixture (I). The resulting acidic composition is useful for destroying microorganisms, having a pH of negative 3 (−3). The inventive step of the present invention requires the addition of compounds containing metallic ions for the extensive antimicrobial properties discussed herein. The following physical and chemical properties are observed when undiluted.
pH=−3 which was determined by a non acidified hydrogen proton count with the data corrected for any electrode type errors, and was performed by EFE&H analytical services, an EPA (Environmental Protection Agency) approved laboratory stability of metallic ions in solution: from approximately 0 pH up to approximately 9 pH stability of metallic ions with temperature: from approximately 32° F. to the point of vaporization or approximately 212° F.
[0048] Various other compounds with metallic ions may be substituted for copper sulfate pentahydrate. The following metal salts are suitable substitutes:
[0049] Copper sulfate, copper glutamate, zinc oxide, zinc glutamate, magnesium glutamate, magnesium sulfate, silver sulfate, silver oxide, and combinations thereof.
[0050] Referring now to the composition of pHarlo Blue 0020, hereinafter referred to as PHB0020, it is an antimicrobial, anti-bacterial agent, which has a formulation that is generally recognized as safe (GRAS) by the US Food and Drug Administration. PHB0020 is useful in the pre-harvest and post-harvest treatment of food sources and foods, including, but not limited to, plants, fruit, vegetables, eggs, poultry, seafood, meats, and animal and pork products. The ratio of ingredients combined for processing is listed below in Table A:
TABLE A Ingredient Percentage Copper Sulfate Pentahydrate 16.4 Sulfuric Acid (processing 9.9 aid) Ammonium sulfate 2.2 Distilled water 71.5
The ingredients form a concentrate, which is combined in small amounts of less than 0.10 milliliters (ml) with 1 gallon of water to make PHB0020.
[0051] The examples, graphs and charts below provide greater detail on the use and effectiveness of PHB0020 as an antimicrobial agent and food additive.
EXAMPLE 1
[0052] In processing plants for poultry and animal products, it is customary to use various water treatment processes, such as a scalding tank, spray bath, final rinse and chill water tank. The scalding tank is used to dip poultry prior to the removal of feathers; other animals are dipped to remove the outer coating of fur or hair. The scalding process permits cross contamination and spread of pathogens. It is important for the safety of the human food supply to provide an additive that can be used in water treatments to inhibit the growth and spread of pathogens and deleterious bacteria. The ideal additive would not evaporate at boiling point temperatures, would not be destroyed by high temperatures and would not be bound by organic material, such as blood and feces and rendered useless.
[0053] The effect of PHB0020 on pathogenic, indicator, and spoilage populations of bacteria associated with broiler chicken carcasses in a poultry scald water application is determined in one embodiment of the present invention.
[0054] First, scalder water was collected from the overflow or entrance end of a commercial poultry scalder. The water is sterilized or autoclaved to eliminate all populations of bacteria and bacterial spores to avoid interference during the study. The autoclaved scalder water is evaluated chemically and compared to raw scalder water to ensure that the organic material demand in raw and autoclaved scalder water is similar.
[0055] Next, sets of test tubes are prepared by adding 9 milliliters (ml) of sterilized scalder water to sterile polystyrene test tubes. One set is prepared as controls by adding 9 ml of sterilized scalder water to tubes. One set is prepared by adding 9 ml of sterilized scalder water and PHB0020 (the disinfectant) until the pH of 2.2 is achieved.
[0056] Each bacterium is exposed, one at a time, to the sterilized scalder water with PHB0020 sanitizer for approximately 2 minutes at approximately 130° F. (55° C.) to mimic scalding.
[0057] After the exposure period, one ml of the suspension was enumerated using the aerobic plate count method by pour plating and incubating at approximately 95° F. (35° C.) for 48 hours.
[0058] Table I below records microbial growth results in a scalder water project wherein sterilized water was heated to scalding temperatures of in a range of from approximately 120° F. (49° C.) to approximately 140° F. (60° C.), preferably to a temperature of approximately 130° F. (55° C.). Various concentrations of PHB0020 are added in a range between approximately 0.4 parts per million (ppm) to approximately 0.8 ppm, preferably at approximately 0.6 ppm and colonies of pathogens, indicator bacteria and spoilage bacteria are exposed to the treated scalder water.
TABLE I Scalder Water Project Control Colonies forming Log Growth after Exposure Sample No.: Bacteria Units of Reduction to Treated Scalder Water Bacteria: Salmonella typhimurium 1 430 2.633468 negative (no growth) 2 880 2.944483 negative 3 970 2.986772 negative 4 450 2.653213 negative 5 620 2.792392 negative 6 700 2.845098 negative 7 1140 3.056905 negative 8 620 2.792392 negative 9 580 2.763428 negative Bacteria: Staphylococcus aureus 1 530 2.724276 negative (no growth) 2 550 2.740363 one (1) colony growing 3 580 2.763428 negative 4 500 2.698970 negative 5 540 2.732394 negative 6 420 2.623249 negative 7 530 2.724276 negative 8 480 2.681241 one (1) colony growing 9 470 2.672098 negative Bacteria: Pseudomonas fluorescens 1 540 2.73234 negative 2 880 2.944483 negative 3 790 2.897627 negative 4 620 2.792392 negative 5 1120 3.049218 negative 6 790 2.897627 one (1) colony growing 7 5200 3.716003 negative 8 1360 3.133539 negative 9 1040 3.017033 negative Bacteria: Listeria monocytogenes 1 1720 3.235528 five (5) colonies growing 2 1840 3.264818 six (6) colonies growing 3 1440 3.158362 negative (no growth) 4 1820 3.260071 five (5) colonies growing 5 1440 3.158362 one (1) colony growing 6 1880 3.274158 negative 7 1720 3.235528 negative 8 1720 3.235528 negative 9 1740 3.240549 negative Bacteria: Shewanella putrefaciens 1 50 1.698970 negative (no growth) 2 50 1.698970 negative 3 60 1.778151 negative 4 20 1.301030 negative 5 50 1.698970 negative 6 70 1.845098 negative 7 80 1.903090 negative 8 20 1.301030 negative 9 30 1.477121 negative Bacteria: Escherichia coli 1 15100000 7.178977 460 colonies growing 2 12900000 7.110590 negative (no growth) 3 13300000 7.123852 32 colonies growing 4 12200000 7.086360 1170 colonies growing 5 13400000 7.127105 4700 colonies growing 6 12200000 7.086360 57 colonies growing 7 14200000 7.152288 900 colonies growing 8 13600000 7.133539 410 colonies growing 9 7600000 6.880814 37 colonies growing
[0059] Referring now to FIG. 1 , the graph shows the effect of PHB0020 on pathogenic and spoilage bacteria identified in the table above. The graph is divided in two sections, on the left is the control showing the logarithm of colony forming units for each bacterium and on the right is the graph of colony forming units after each bacterium is exposed for 2 minutes to scalder water treated with PHB0020. The graph shows that Listeria , a gram-positive bacterium, is hard to kill and E coli , a very prolific bacterium, has the highest reduction after a 2 minute exposure.
[0060] In FIG. 2 , the graph shows the logarithm of the reduction of bacterial levels for each bacterium. In most cases the log of colony forming units is less than three, with the most prolific bacterium, E coli having a log of less than five.
[0061] Thus, PHB0020 functions as an antimicrobial agent, disinfectant, or sanitizer and is extremely effective for eliminating populations of pathogenic, indicator and spoilage bacteria in commercial scalder water under industrial scalding conditions. PHB0020 is an effective means for controlling bacteria in scalder water and may be used for controlling cross-contamination during scalding. Disinfection of poultry scalder water is crucial because it is the first area within the plant in which birds are immersed in a common bath and bacteria may be transferred from bird to bird.
[0062] The efficacy of PHB0020 as an antimicrobial agent is suitable for many other uses and in the quantitative ranges identified below in Table J:
TABLE J Use Levels in Milligrams per Liter (mg/l): Range Target Application for PHB0020: PRE-HARVEST Hatcheries 1.0 to 2.0 mg/l 1.3 mg/l Egg- wash 0.8 to 1.5 mg/l 1.0 mg/l Drinking water for livestock 0.8 to 2.0 mg/l 1.2 mg/l Animal feed 0.6 to 2.0 mg/l 1.0 mg/l Seafood water supply 0.4 to 1.5 mg/l 0.8 mg/l (species dependent) Animal foot disinfectant Approximately 1 mg/l Approximately to 20 mg/l approximately 50 mg/l POST-HARVEST Poultry: (chicken, turkey, game birds, ostrich, duck, geese, pheasants) 1. Scalder 0.4-0.8 to 3 mg/l Water chemistry dependent 2. Chill Tank 0.6-1.0 mg/l 0.8 mg/l 3. Final Rinse 0.4-0.8 mg/l 0.6 mg/l Red Meat 0.8-1.2 mg/l 1.0 mg/l Seafood (fish, shell fish, 0.4-1.0 mg/l 0.8 mg/l frogs, octopus, squid) Wastewater 0.6 to 1.0 mg/l 0.8 mg/l Airborne contaminants on 0.4 to 1.0 mg/l 0.8 mg/l cooked food Preservative coating 0.4 to 0.8 mg/l 0.6 mg/l Ingredient in Ice Products 0.6 to 1.0 mg/l 0.8 mg/l
The table above identifies some of the applications for the present invention; it is an indication of the enormous commercial potential for the novel antimicrobial composition that can be used to protect public health.
[0063] Pre-harvest and non-food uses for the composition of the present invention are discussed in further detail. The composition can be produced in several forms when diluted with distilled water, such as, an aerosol, mist, vapor or fog to produce micron sized particles that remain in suspension in the air for a period of time and act on airborne pathogens that come in contact with the composition. The composition of the present invention can remove ammonia odors from hatcheries, improve the quality of animal water supply and it can be used in solutions for washing, coating and otherwise disinfecting food products prior to harvesting, such as in hatcheries, dairies and in egg washes. Another use can be for the oral care and as a foot wash or disinfectant for dairy cattle. As would be expected, many non-food uses of the composition of the present invention can include, effective control of microbial or pathogenic populations, as found on food preparation equipment, utensils, counter tops, transport belts, boot and hand-wash-dip pans, storage facilities, air circulation systems, coolers, blanchers, walls, floors and the like.
[0064] Specific post-harvest treatment of plants and animals include, but are not limited to, aqueous treatment of plants, fruits, vegetables, animal by-products, fish and shellfish. The treatment includes washing, soaking and cleaning the food product and the composition of the present invention is effective in the scalder tank, rinse and spray streams and chiller. The end result is a safer, healthier food supply for man and other animals.
[0065] 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. | An antimicrobial, anti-bacterial processing aid, food additive and food ingredient is provided to inhibit cellular growth of known pathogenic, indicator and spoilage organisms, such as salmonella, stahphylococcus, listeria, e coli , and the like. The antimicrobial agent of the present invention is useful as a treatment for animal feed, a treatment for pre-harvest and post-harvest processing of foodstuffs, a treatment for cooked food subject to airborne contaminants and many other conditions in need of disinfectants and sanitizers. One of the primary benefits of the antimicrobial agent is that it inhibits the growth of bacteria that have become antibiotic resistant. | 2 |
BACKGROUND OF THE INVENTION
[0001] Model-driven architecture (MDA) is an approach to software development advocated by the Object Management Group (OMG). See A. Kleppe, J. Warmer and W. Bast, “MDA Explained: The Model Driven Architecture: Practice and Promise”, Addison-Wesley, Boston, Mass., 2003. It provides a set of guidelines for structuring software specifications in the form of models. The approach suggests describing a software system's specifications using a platform independent model (PIM). A PIM is usually specified in a language defined using the Meta Object Facility (MOF), a standard by the OMG for describing modeling languages. A prominent example of such a language is the Unified Modeling Language (UML), a general purpose modeling language that is well adopted by the software engineering community. Alternatives to UML also exist and are collectively referred to as Domain Specific Languages (DSL), as they are more specialized and target certain domains. See M. Mernik, J. Heering, and A. M. Sloane, “When and How to Develop Domain-Specific Languages.” ACM Computing Surveys, 37(4):316-344, 2005.
[0002] Once a software system has been specified using a PIM, a platform is then chosen to realize it using specific implementation technologies, producing what is referred to as a platform specific model (PSM). A PSM can be specified using several domain specific languages. The process of going from (translating) a PIM to a PSM is called model-to-model transformation and can usually be automated.
[0003] An alternative way to defining DSLs is through UML profiles. A UML Profile is a light-weight extensibility mechanism for UML. It contains a collection of stereotypes extending certain types from UML and adding properties to them. Unlike a heavy weight extension, which is done by extending the meta-model (an M2 level model), a profile is an M1-level extension. In this regard, extending M2 using M1 constructs, a profile is unique and presents interesting challenges to tool developers and users.
[0004] The challenge for modeling tool is to allow users to work seamlessly with profiles and MOF-based DSLs. One kind of tool where this challenge presents itself is model to model transformation tools. A typical requirement here is to develop transformations from UML models with certain applied profiles to UML models with different applied profiles. Alternatively, the transformations could be from UML models with applied profiles to other MOF-based DSLs, or vice versa. For example transformations see: OMG, MOF QVT Final Adopted Specification, OMG Documentptc/ 05-11-0; P. Swithinbank, M. Chessell, T. Gardner, C. Griffin, J. Man, H. Wylie and L. Yusuf, “Patterns: Model-Driven Development Using IBM Rational Software Architect (Section 9.5.2),” IBM Redbooks at www.redbooks.ibm.com/redbooks/pdfs/sg247105.pdf; R. Popma “JET Tutorial,” at www.eclipse.org/articles/Article-JET/jet_tutoriall.html; C. Griffin “IBM Model Transformation Framework 1.0.0: Programmer's Guide. 2004,” at www.alphaworks.ibm.com/tech/mtf, Fujaba Tool Suite 4, University of Paderborn Software Engineering, www.fujaba.de; G. Taentzer “AGG: A Graph Transformation Environment for Modeling and Validation of Software.” Application of Graph Transformations with Industrial Relevance ( AGTIVE' 03) 3062 , pp. 446-453 (2003). These and most transformation approaches today, either do not attempt to solve this problem or leave it to the user to deal with it. However, given the fact that profile implementations are almost always different from those of DSLs, users are faced with steep learning curves and a lot of complexities coming from dealing with two different meta-level constructs.
SUMMARY OF THE INVENTION
[0005] The present invention addresses the short comings and foregoing problems of the prior art. The main idea of the invention is to specify transformations involving UML profiles declaratively using meta-model mapping, in a consistent way to regular DSL mapping, then use a transformation from that specification to generate an imperative transformation implementation that hides the complexity of dealing with profiles at runtime. The approach is implemented as an extension to the Model Transformation Authoring Framework (MTAF) by allowing profiles to be specified as an input and/or output domain along with the UML2 meta-model. Further details on MTAF are described in U.S. patent application Ser. No. ______ (Attorneys Docket number CAM9-2007-0204) for “Computer Method and Apparatus for Providing Model to Model Transformation Using an MDA Approach” by assignee, as well as in IMB Rational Software Architect Version 7.0, both herein incorporated by reference.
[0006] Once a profile is specified as a domain, mappings can be created between hybrid types consisting of UML types stereotyped with one or more stereotypes from those profiles. The properties of those stereotypes, along with properties from the UML type, then become available for mapping in a similar way. Profiles can also contain types in addition to stereotypes. Those types can also be mapped in a similar way to DSL types.
[0007] All the basic mapping rules, provided by MTAF, are used without change in the declarative specification. However, the imperative implementations of those rules are extended to become aware of UML profiles. Since MTAF provides a transformation between the declarative specification and its implementation, the details can be hidden from the user satisfying the requirement described in the problem statement.
[0008] In one embodiment, a system and method for providing and/or authoring model-to-model transformation of programming models involving profiles, comprises the steps of:
[0009] using a declarative mapping between domains that can have one or more profiles applied on a source side and/or a target side, specifying transformation of profiles and resulting in a declarative specification; and
[0010] generating a transformation code implementation based on the declarative specification including allowing a given profile to be specified as an input domain or as an output domain along with a meta model of a subject programming model. The generated transformation code implementation effectively handles complexities of dealing with the given profile at run time. The generated transformation code implementation is provided as a MTAF API.
[0011] In some embodiments, the declarative specification further forms hybrid types from types in the target side and stereotypes from one or more profiles; and the declarative specification creates mappings from/to those hybrid types on the fly including the properties of both the mapped type and the stereotypes.
[0012] With the present invention, a profile can be on the source side or target side of a transformation mapping process. It is not a requirement to have profiles on both sides (i.e., the invention is not limited to profile-to-profile mapping) but is flexible enough that a profile can be specified along with the UML metamodel if the profile is specified as source and/or target of a mapping.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention.
[0014] FIG. 1 is a schematic illustration of a declarative mapping from a domain specific language model (input domain meta model) to a transformation API (output domain meta model) in accordance with the present invention.
[0015] FIG. 2 is a block diagram of the UML2 profile semantics.
[0016] FIG. 3 is a block diagram of a new domain type extending the UML type and stereotypes according to principles of the present invention.
[0017] FIG. 4 is a schematic view of an input domain meta model and output domain meta model in an example of the present invention.
[0018] FIG. 5 is a block diagram of a ModelToRoot mapping declaration in an embodiment of the present invention.
[0019] FIG. 6 is a block diagram of a PackageToProject mapping declaration in an embodiment of the present invention.
[0020] FIG. 7 is a block diagram of a PackageToPackage mapping declaration in an embodiment of the present invention.
[0021] FIG. 8 is a block diagram of the ClassToBean mapping declaration in an embodiment of the present invention.
[0022] FIG. 9 is a block diagram of a PropertyToAttribute mapping declaration in an embodiment of the present invention.
[0023] FIG. 10 is a schematic view of a computer network environment in which embodiments of the present invention are implemented.
[0024] FIG. 11 is a block diagram of a computer node in the computer network of FIG. 10 .
DETAILED DESCRIPTION OF THE INVENTION
[0025] A description of example embodiments of the invention follows.
[0026] In a preferred embodiment, applicants use the MTAF framework to provide the ability to author transformations between input and output Ecore-based DSLs. Ecore-based DLSs are further detailed in F. Budinsky, D. Steinberg, T. Grose, S. Brodsky and E. Merks, “Eclipse Modeling Framework”, Pearson Education, August 2003, herein incorporated by reference. More generally, the first step in the invention authoring process is to map the input domain meta-model and the output domain meta-model DSLs using a declarative mapping DSL 27 . One such declarative mapping DSL 27 is provided by MTAF as illustrated in FIG. 1 . The result of the first step is a mapping model (transformation specification) 25 that specifies how the input domain DSLs relate to the output domain DSLs.
[0027] The second step in the invention authoring process is to generate an imperative transformation implementation using a framework API provided by MTAF. The mapping between the formed transformation specification 25 and the corresponding code implementation (transformation API 29 ), shown in FIG. 1 , is implemented as a JET (JAVA Emitter Template) model-to-text transform in one embodiment.
[0028] In particular the mapping root 24 translates and corresponds to a RootTransformation 30 . The mapping declaration 27 translates to a MapTransform 28 construct in the transformation API 29 . That is, move mapping 10 , CustomMapping 12 and SubmapMapping 14 elements of the MappingDeclaration 27 correspond to a MoveRule 20 , CustomRule 16 and SubmapExtractor 18 respectively of the transformation API 29 . Similar correspondence of Subelements of these elements and other correspondences are further discussed below.
[0029] The present invention extends the MTAF to support the transformation to/from UML profiles whose semantics are shown in FIG. 2 . By way of background the modeling architecture for UML2 can be viewed using a four layer metamodel hierarchy. These layers provide for the meta-metamodel (e.g. infrastructure library), the metamodel (UML2), the user model (the model defined in the user's problem domain), and the application layer (the layer of user code that exploits the model they have defined). For reference, the following Table 1 outlines the four level meta-model hierarchy, including a description of each level and an example of the information found at each level:
[0000]
TABLE 1
Four-Level Metamodel Hierarchy
Level
Description
Examples
M3
Meta-metamodel
Instances of ECore
Applicants solution uses ECore but there are other frameworks
EPackage, EClass,
as well.
EAttribute, EReference
The model used to define meta-models
Forms the foundation of the metamodeling hierarchy providing
the basic work units for the meta model.
M2
UML 2 meta-model
Instances of ECore
Every element in the meta-model is an instance of an element in
Package, Class, Property,
the meta-metamodel.
Association
Defines a language for specifying models
M1
User model
Instances of UML2 elements
An instance of the metamodel.
MyClass, Date, etc.
allows users to define their problem domain
M0
Run-time instances
Instances of User model
contains run-time instances of model elements
myClass, date, etc.
[0030] In general, a UML “profile” is a type of package 19 and is formed of (or has) a collection of stereotypes 13 . A stereotype 13 is a type of class 15 (in the object oriented programming sense) and has zero or more properties 17 . A typical example UML2 profile contains a stereotype that extends a metaclass. Illustrated in FIG. 2 is an example Profile 11 consisting of a stereotype extension 13 to the UML2 metaclass “Class” 15 . The illustrated stereotype “Stereotype” 13 adds new properties (generally 17 ) to the metaclass “Class” 15 .
[0031] In terms of how the UML2 models this example, the diagram shown in FIG. 2 details the semantic structure of the stereotype definition. Stereotype 13 is diagrammed as an extension 21 and as having “owned” attributes 23 . Although the stereotype 13 is at the M1 level (see Table 1), it is diagrammed as extending M2 classes.
[0032] Returning to the present invention, first, the extensions related to the declarative mapping DSL 25 are discussed. Basically, one or more UML Profiles 11 are allowed to be input domains or output domains to a MappingRoot 24 ( FIG. 1 ). However, since a profile 11 is an extension to the UML meta-model, that meta-model has to also be specified as a domain in the same side as the Profile 11 .
[0033] Once a profile 11 is specified as a domain, the profile is converted on-the-fly from an M1 instance to an M2 instance using a UML->Ecore transformation provided in UML2: EMF-based UML 2.0 Metamodel Implementaion at www.eclipse.org/uml2. The resulting Ecore model 29 representing the profile 11 is used instead by the mapping editor in the declarative specification 25 . The details are discussed next.
[0034] Profiles 11 have a collection of Classes 15 and Stereotypes 13 , which are allowed to be input domains and output domains of MappingDeclarations 27 . While a profile Class 15 can directly be an input domain or an output domain of a MappingDeclaration 27 , a profile Stereotype 13 can be specified as a domain only if a type (from UML) that is extended by this Stereotype 13 is also specified as a domain in the same side. One or more applicable stereotypes 13 (from the same or different profiles 11 ) can be specified at the same time for the same type as a domain. In this case, a new M2 type is created on the fly to represent this domain. The new type multi-inherits both the UML type 31 and all the stereotypes 13 a, . . . n (in their M2 representation). FIG. 3 shows the new resulting domain type 35 .
[0035] The subject Profile Classes 15 and Stereotypes 13 have attributes of type Property 17 , which get converted to EStructuralFeatures. These features are allowed to be input domains and output domains for the various kinds of mappings that can be nested in a MappingDeclaration 27 in a similar way to regular EStructuralFeatures coming from a type in a DSL. In case of a domain with stereotypes 13 , the newly created domain type 35 multi-inherits all the features coming from the base UML type 31 and all the stereotypes 13 , exposing the stereotype's properties 17 for mapping.
[0036] The present invention second extension to MTAF, related to UML profiles 11 , include specific extensions to the provided imperative transformation API 29 . For example, a special subtype of the ‘accept’ Condition 22 for MapTransform 28 rules 16 , 18 , 20 , 26 is provided to additionally check for applied stereotypes on UML elements if the input domains of the transform include stereotypes 13 . An input mapping element 10 , 12 , 14 passes the condition 32 only if all the input domain stereotypes 13 are applied to it. Also, a special subtype of CreateRule 26 is provided to apply stereotypes 13 to the created UML elements if the output domains include those stereotypes. If the output domain contains instead a profile-defined type, the rule also knows how to create instances of that type. Finally, special subtypes of MoveRule 20 and SubmapExtractor 18 are provided to provide access to corresponding/respective profile-defined input and output domain properties (mapped from condition refinements 34 a, b, c to conditions 36 a, b, c ) namely a stereotype's properties and a profile type's properties.
[0037] Exemplification
[0038] The example of FIG. 4 demonstrates a typical transformation mapping between a high level DSL (UML2+Bean Profile), used to capture a design, and a low level DSL (BeanCodeGenerator) used for java beans code generation. This example illustrates the present invention 100 features using the tooling provided by MTAF to specify a model to model transformation involving profiles.
[0039] MTAF provides an Eclipse-based mapping editor that allows for choosing the input and output DSLs as domains of a MappingRoot 24 . In the example, the input DSLs (input domain meta models) 41 are UML2+Bean Profile, generally at 42 , 13 a , 15 , 17 while the output DSL (output domain meta model) 43 is BeanCodeGenerator. Five declarations are then identified:
[0040] ModelToRoot. This mapping, shown in FIG. 5 , is from Model EClass 42 of UML2 to Root EClass 44 of BeanCodeGenerator. The input domain meta model name is mapped to the output domain meta model name using a CustomMapping 12 with the custom Java code: ‘Root_tgt.setName(“Beans “+Model_src.getName( ));’. Also, the input's packagedElement 40 is mapped to the output's project 360 using a SubmapMapping 14 with reference to the ‘PackageToProject’ declaration of FIG. 6 .
[0041] PackageToProject. This mapping, shown in FIG. 6 , is from Package EClass 46 of UML2, with the beanproject Stereotype 48 , to Project EClass 45 of BeanCodeGenerator. The input's name is mapped to the output's name using a MoveMapping 10 . The input's basepackage 17 a (a stereotype property) is mapped to the output's basepackage 17 b using a MoveMapping 10 . Finally, the input's packagedElement 40 is mapped to the output's package 402 using a SubmapMapping 14 with reference to the ‘PackageToPackage’ declaration of FIG. 7 .
[0042] PackageToPackage. This mapping, shown in FIG. 7 , is from Package EClass 46 of UML2 to Package EClass 47 of BeanCodeGenerator. The input's name is mapped to the output's name using a MoveMapping 10 . The input's packagedElement 40 is mapped to the output's bean 49 using a SubmapMapping 14 with reference to the ‘ClassToBean’ declaration ( FIG. 8 ). Also, the input's packagedElement 40 is mapped to the output's export 37 using a SubmapMapping 14 with reference to the ‘ClassToBean’ declaration. However, this last mapping has the following refinements 34 : an ‘accept’ Condition 22 with the OCL expression ‘Package_src.visibility=Visibility.Public’, an ‘inputFilter’ 36 a with the OCL expression ‘packagedElement_src.visibility=Visibility. Public’, and an ‘outputFilter’ 36 b with the Java code ‘return !export_tgt.get Attribue( ).isEmpty( );’.
[0043] ClassToBean. This mapping, shown in FIG. 8 , is from Class EClass 15 of UML2, with the bean Stereotype 13 a , to Bean EClass 38 of BeanCodeGenerator. The input's name is mapped to the output's name using a MoveMapping 10 . The input's ownedAttribute 23 is mapped to the output's attribute 39 using a SubmapMapping 14 with reference to the ‘PropertyToAttribute’ declaration of FIG. 9 . The last mapping has a custom ‘extractor’ 36 c with Java code ‘return Utils.getAllAttributes(Class_src);’.
[0044] PropertyToAttribute. This mapping, shown in FIG. 9 , is from Property EClass 17 of UML2 to Attribute EClass 401 of BeanCodeGenerator. The input's name is mapped to the output's name using a MoveMapping 10 . The input EClass is mapped to the output's kind using a CustomMapping 12 with the custom Java code: ‘Attribute_tgt.setKind (Property_src.getUpper( )>1||Property_src.getUpp er( )==−1)?“LIST”:“FIELD”);’. The input type is mapped to the output's type using a CustomMapping 12 with the custom Java code: ‘Attribute_tgt.setType (Property_src. getType( ).getName( ));’.
[0045] FIG. 10 illustrates a computer network or similar digital processing environment in which the present invention may be implemented.
[0046] Client computer(s) 50 and server computer(s) 60 provide processing, storage, and input/output devices executing application programs and the like. Client computer(s) 50 can also be linked through communications network 70 to other computing devices, including other client devices/processes 50 and server computer(s) 60 . Communications network 70 can be part of a remote access network, a global network (e.g., the Internet), a worldwide collection of computers, Local area or Wide area networks, and gateways that currently use respective protocols (TCP/IP, Bluetooth, etc.) to communicate with one another. Other electronic device/computer network architectures are suitable.
[0047] FIG. 11 is a diagram of the internal structure of a computer (e.g., client processor 50 or server computers 60 ) in the computer system of FIG. 10 . Each computer 50 , 60 contains system bus 79 , where a bus is a set of hardware lines used for data transfer among the components of a computer or processing system. Bus 79 is essentially a shared conduit that connects different elements of a computer system (e.g., processor, disk storage, memory, input/output ports, network ports, etc.) that enables the transfer of information between the elements. Attached to system bus 79 is I/O device interface 82 for connecting various input and output devices (e.g., keyboard, mouse, displays, printers, speakers, etc.) to the computer 50 , 60 . Network interface 86 allows the computer to connect to various other devices attached to a network (e.g., network 70 of FIG. 10 ). Memory 90 provides volatile storage for computer software instructions 92 and data 94 used to implement an embodiment of the present invention (e.g., transformation authoring system and tool 100 , declarative mapping 27 , mapping model/specification 25 , transformation API 29 and supporting method/ process detailed above in FIGS. 1-9 ). Disk storage 95 provides non-volatile storage for computer software instructions 92 and data 94 used to implement an embodiment of the present invention. Central processor unit 84 is also attached to system bus 79 and provides for the execution of computer instructions.
[0048] In one embodiment, the processor routines 92 and data 94 are a computer program product (generally referenced 92 ), including a computer readable medium (e.g., a removable storage medium such as one or more DVD-ROM's, CD-ROM's, diskettes, tapes, etc.) that provides at least a portion of the software instructions for the invention system. Computer program product 92 can be installed by any suitable software installation procedure, as is well known in the art. In another embodiment, at least a portion of the software instructions may also be downloaded over a cable, communication and/or wireless connection. In other embodiments, the invention programs are a computer program propagated signal product 107 embodied on a propagated signal on a propagation medium (e.g., a radio wave, an infrared wave, a laser wave, a sound wave, or an electrical wave propagated over a global network such as the Internet, or other network(s)). Such carrier medium or signals provide at least a portion of the software instructions for the present invention routines/program 92 .
[0049] In alternate embodiments, the propagated signal is an analog carrier wave or digital signal carried on the propagated medium. For example, the propagated signal may be a digitized signal propagated over a global network (e.g., the Internet), a telecommunications network, or other network. In one embodiment, the propagated signal is a signal that is transmitted over the propagation medium over a period of time, such as the instructions for a software application sent in packets over a network over a period of milliseconds, seconds, minutes, or longer. In another embodiment, the computer readable medium of computer program product 92 is a propagation medium that the computer system 50 may receive and read, such as by receiving the propagation medium and identifying a propagated signal embodied in the propagation medium, as described above for computer program propagated signal product.
[0050] Generally speaking, the term “carrier medium” or transient carrier encompasses the foregoing transient signals, propagated signals, propagated medium, storage medium and the like.
[0051] While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
[0052] For example, the present invention may be implemented in a variety of computer architectures. The computer network of FIGS. 10 and 11 are for purposes of illustration and not limitation of the present invention.
[0053] The invention can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, etc.
[0054] Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer readable medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.
[0055] The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read/write (CD-R/W) and DVD. | A method and apparatus for authoring model-to-model transformations of programming models involving profiles is disclosed. Using a declarative mapping between a given profile of a subject programming model and a target profile of a target programming model, transformation of the given profile is specified and results in a declarative specification. Similarly the declarative mapping may be to a profile of a target programming model (without a corresponding source side profile) or from a profile of a source programming model (without a corresponding target side profile). Based on the declarative specification, a transformation code implementation (e.g. a transformation API) is generated. The given profile is specified as an input domain or as an output domain along with a meta model of the subject programming model. The generated transformation code implementation effectively handles complexities of dealing with the given profile at run time. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing potassium titanate fibers which are used as a composite filler material for plastics and metals, a filter material, as a membrane or in electronic appliances. More particularly, it relates to a method for manufacturing longer fibers of potassium titanate or derivatives of potassium titanate.
PRIOR DEVELOPMENT
Various methods for manufacturing potassium titanate fibers have been developed including the fusion process of reacting a mixture of raw materials by heating and fusing; the flux process of adding a flux to the mixture during heating and fusing; the calcination process of reacting the raw material at a temperature lower than the fusing point; and the method of calcination in which the temperature is controlled. These processes, however, are all defective in the fibers having only a short length of 100 μm or less result.
Because of the short length, potassium titanate fibers do not fully display their excellent features and the fiber length and this has limited their application.
Indeed longer lengths are advantageous, for example, when potassium titanate fibers are added as reinforcing materials to composite plastics since interlocking of these longer fibers is accelerated to achieve a higher reinforcing effect with a smaller amount of fiber addition.
In the conventional calcination method of manufacturing potassium titanate fibers, the mixing ratio of the raw material titanium-containing compound and the potassium-containing compound is set such that the potassium-containing compound is slightly in excess than in the titanium and potassium ratio in the resultant product. In such a condition, a portion of K 2 O evaporates the reaction of the above process and accelerates the fiber growth. The evaporation speed of K 2 O should not be too fast or too slow in order to obtain the longer fibers.
Since open state calcination for manufacturing potassium titanate fibers may cause excessive evaporation of K 2 O, there is a process using a vessel with a comparatively small opening. A sintering vessel of this type made of a porous material with adequate permeation to promote adequate evaporation and diffusion of K 2 O, thereby producing a comparatively longer fiber length product.
Conventional vessels are made primarily of alumina-silica materials. However, such calcination vessels react with its component, K 2 O, at about 700° C. and forms K 2 O. 4SiO (potassium tetrasilicate) or K 2 O. Al 2 O 3 . 6SiO (potash feldspar) to coat the inside surface of the alumina-silica vessel to thereby prevent gas permeation. This increases the K 2 O vapor pressure inside the container also serves to restrain fiber growth.
DETAILED DESCRIPTION OF THE INVENTION
The inventors of the present invention have found that potassium titanate fiber length can be extended using a calcination vessel such as a saggar or crucible in the calcination method, the vessel made of a material containing 25 wt % or more MgO. The calcination method is for industrial production among those described above, and completed the present invention.
Since the MgO component in the material forming the vessel is not only non-reactant to K 2 O but also reduces or eliminates any reaction of the material with K 2 O, plugging of the micro pores is prevented. During the generation of potassium titanate, K 2 O is diffused and discharged outside the container through open pores. As a result, the K 2 O vapor pressure inside the vessel does not increase, nor is K 2 O evaporation restrained and as a result fiber growth is promoted to produce longer fibers.
As described in the above, the present invention is characterized in that the calcination vessel material contains 25 wt % or more of MgO present, for example, as magnesia dolomite or chrome-magnesite added at the time of the vessel is made. With less than 25 wt % of MgO, the reaction with other compounds, particularly of SiO 2 and K 2 O, cannot be restrained and plugging of the micro pores occurs, so that the desired effect to the MgO addition is not demonstrable.
If a basic material such as magnesia, dolomite or chrome-magnesite is used mainly for manufacturing the calcination vessel, a particularly preferable result is achieved since the MgO content will exceed 50 wt % and SiO 2 content, which is an impurity, will be reduced. If the MgO content is at least 25 wt %, if not as much as 50 wt %, MgO will react with SiO 2 to form compounds such as 2 MgO SiO 2 (Forsterite) and decrease any possible reaction with K 2 O. Thus, the present inventors confirmed that K 2 O diffusion through micro pores of the container is not particularly hampered. Although there is no particular restriction on the composition of the calcination vessel other than the MgO component, several experiments indicate that the SiO 2 content should preferably be at most 25 wt %.
The method of manufacturing potassium titanate fibers according to the calcination method using the basic calcination vessel of the present invention is now explained.
One or more materials selected from the group consisting of potassium carbonate, potassium hydrogen carbonate, potassium hydroxide, potassium sulfate, potassium nitrate, potassium chloride, potassium bromide, potassium and of fluoride, titanium dioxide and titanium hydroxide are weighed and mixed together to achieve the molecular ratio of 1 : 1 to 8, preferably 1 : 1 to 5, for K 2 O and TiO 2 , to the resultant mixture water is added and is kneaded to prepare a paste or is compression molded, and then heated at 900° C.-1250° C. for 30 minutes to 1000 hours, preferably for 20 hours to 50 hours.
Fibers of potassium titanate thus prepared are dipped into water, disentangled and then removed.
By further treating these fibers with an acid solution, potassium titanate or oxide fibers with a different K 2 O/TiO 2 ratio may be obtained, or by treating them in an alkaline aqueous solution with an alkaline earth metal compound, fibers of various titanium compounds, such as titanate alkaline earth metals, may be obtained.
The present invention enables the industrial scale manufacture of potassium titanate fibers with a length of 0.1-5 mm.
EXAMPLE
Table 1 shows the chemical composition and physical properties of the calcination vessel of the present invention.
To potassium carbonate and titanium dioxide in the amounts as shown in Table 2 were added 13 wt. parts water to 100 parts dry mixture and the resultant mixture was compression molded into a shape of 230×115×65 mm, which was placed in a calcination vessel and then heated for 50 hours at the temperatures shown in Table 2. After cooling, the product was dipped into water. The size of fibers taken out are reported in Table 2.
As is apparent from the results in Table 2, potassium titanate fibers of the Examples which were heated in the calcination vessel containing 25 wt % or more of MgO had much a longer fiber length compared to those obtained in Comparative Examples, thereby proving the superiority of the present invention method.
TABLE 1__________________________________________________________________________ Apparent CompressionSaggar Chemical composition (wt %) porosity Apparent Bulk strengthNo. Material SiO.sub.2 Al.sub.2 O.sub.3 Fe.sub.2 O.sub.3 CaO MgO Cr.sub.2 O.sub.3 TiO.sub.2 (%) density density (kg/cm.sup.2)__________________________________________________________________________1 Magnesia 0.3 0.2 0.1 0.8 98.6 -- -- 17.3 3.51 2.90 5002 Dolomite 1.5 0.4 0.8 20.0 77.3 -- -- 16.8 3.50 2.91 5503 Chrome-magnesite 0.8 12.9 3.9 0.7 71.1 10.6 -- 16.3 3.67 3.07 6004 Spinel 0.2 71.0 0.2 0.4 28.0 -- -- 17.5 3.48 2.87 5005 Magnesia- 24.8 34.5 1.6 0.7 37.2 -- 0.6 18.5 3.01 2.45 400 alumina-silica6 Alumina-silica 31.2 64.7 1.6 0.2 0.3 -- 1.3 18.0 3.05 2.50 500__________________________________________________________________________
TABLE 2__________________________________________________________________________ Examples Comparative Examples 1 2 3 4 5 6 7 8 1 2 3 4__________________________________________________________________________Potassium carbonate (kg) 253 146 146 146 146 146 146 102 253 146 102 146Titanium dioxide (kg) 147 254 254 254 254 254 254 298 147 254 298 254K.sub.2 O/TiO.sub.2 (mol ratio) 1/1 1/3 1/3 1/3 1/3 1/3 1/3 1/5 1/1 1/3 1/5 1/3Annealing temperature (°C.) 1000 1000 1100 1100 1100 1100 1100 1100 1000 1000 1000 1100Saggar material No (Table 1) 1 1 1 2 3 4 5 1 6 6 6 6Fiber length (μm) 100- 100- 300- 300- 300- 100- 100- 100- 20- 20- 20- 20- 300 500 3000 2500 2000 500 300 300 30 50 25 80Fiber diameter (μm) 3-10 3-20 10-40 10-40 10-35 3-20 3-15 4-10 0.8-1 0.8-1.5 0.8-1 1-2Fiber/length diameter 30-33 25-33 30-75 30-62 30-57 25-33 15-33 25-30 25-30 25-33 25-28 25-33Reaction product K4T K4T K4T K4T K4T K4T K4T K6T K4T K4T K6T K4T K6T K6T K6T K6T K6T K6T__________________________________________________________________________ Note: K4T: K.sub.2 O.4TiO.sub.2 K6T: K.sub.2 O.6TiO.sub.2 | Long potassium titanate fibers (100-3000 μm) made by heat reaction in gas permeable calcination vessel, made of material containing at least 25 wt %, preferably at least 50 wt %, MgO to prevent plugging of the vessel during the reaction and maintain gas permeation. | 2 |
This is a continuation of application Ser. No. 07/670,778, filed Mar. 19, 1991, now abandoned.
FIELD OF THE INVENTION
This invention relates to a process for preparing a titanyl phthalocyanine crystal useful as a photoconductive material.
BACKGROUND OF THE INVENTION
Phthalocyanine compounds are useful as coatings, printing inks, catalysts or electronic materials. In recent years, they have been extensively studied particularly for their use as electrophotographic photoreceptor materials, optical recording materials and photoelectric conversion materials.
In general, phthalocyanine compounds are known to exhibit several different crystal forms depending on the process of production or the process of treatment. The difference in crystal form is known to have a great influence on their photoelectric conversion characteristics. For example, known crystal forms of copper phthalocyanine compounds include α-, ε-, π-, χ-, ρ-, and δ-forms in addition to a stable β-form. It is known that these crystal forms are capable of interconversion by a mechanical strain, a sulfuric acid treatment, an organic solvent treatment, a heat treatment, and the like as described, e.g., in U.S. Pat. Nos. 2,770,629, 3,160,635, 3,708,292, and 3,357,989. Further, a relationship between the crystal form of copper phthalocyanine and electrophotographic sensitivity is described in JP-A-50-38543 (the term "JP-A" as used herein means an "unexamined published Japanese patent application").
With respect to titanyl phthalocyanine, too, various crystal forms have been proposed, including a stable β-form as disclosed in JP-A-62-67094, an β-form as disclosed in JP-A-61-217050, and other crystal forms as disclosed in JP-A-63-366, JP-A-63-20365, JP-A-64-17066, and JP-A1-153757.
However, any of the above-described phthalocyanine compounds proposed to date is still unsatisfactory in photosensitivity and durability when used as a photosensitive material. It has thus been demanded to develop a phthalocyanine compound of new crystal form or a process for easily preparing a phthalocyanine compound of stable crystal form.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a process for easily preparing a stable titanyl phthalocyanine crystal having high photosensitivity.
As a result of extensive investigations, the inventors have found that a titanyl phthalocyanine crystal having a stable crystal form which exhibits high sensitivity and durability as a photoconductive material can be obtained by subjecting titanyl phthalocyanine to a simple treatment, and thus reach the present invention.
The present invention relates to a process for preparing a titanium phthalocyanine crystal showing at least one diffraction peak at a Bragg angle (2θ±0.2) of 27.3°, which comprises dissolving or suspending titanyl phthalocyanine in concentrated sulfuric acid to form a solution or a slurry and diluting the solution or slurry with an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and water, a mixed solvent of an aromatic solvent and water, or a mixed solvent of an alcohol solvent and an aromatic solvent with or without water, thereby to precipitate a crystal. If desired, the precipitated crystal is isolated and further treated with an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and an aromatic solvent: or a mixed solvent of an alcohol solvent and/or an aromatic solvent and water.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 through 6 each show the X-ray diffraction pattern (abscissa: Bragg angle (28); ordinate: intensity (CPS)) of the titanyl phthalocyanine crystal obtained in Examples 1 through 6, respectively.
FIG. 7 is an X-ray diffraction pattern of the titanyl phthalocyanine crystal obtained in the Synthesis Example.
DETAILED DESCRIPTION OF THE INVENTION
Titanyl phthalocyanine which can be used in the process of the present invention is synthesized by a known method as described in U.S. Pat. Nos. 4,664,997 and 4,898,799. For example, it is synthesized by reacting 1,3-diiminoisoindoline with titanium tetrabutoxide, or by reacting 1,2-dicyanobenzene (o-diphthalonitrile) with a titanium compound as shown in the following scheme (1) or (2). ##STR1##
In the scheme, Pc represents a phthalocyanine residue. Namely, 1,2-dicyanobenzene and a titaniumhalide are heated in an inert solvent to react. Examples of the titanium halide include titanium tetrachloride, titanium trichloride, titanium tetrabromide and the like, and titanium tetrachloride is preferably used in view of production costs. As an inert solvent, organic solvents having a high boiling point are preferably used, such as trichlorobenzene, α-chloronapthalene, β-chloronapthalene, α-methylnaphthalene, methoxynaphthalene, diphenyl ether, diphenylmethane, diphenylethane, ethylene glycol dialkyl ethers, diethylene glycol dialkyl ethers, triethylene glycol dialkyl ethers and the like. The reaction is generally performed at 150° to 300° C. and preferably at 180° to 250° C. After the reaction, the produced dichlorotitanium phthalocyanine is separated by filtration and washed with a solvent as used in the reaction to remove by-products and unreacted starting materials. Then, the resulting product is washed with an inert solvent such as alcohols (e.g., methanol, ethanol, and isopropyl alcohol) and ethers (e.g., tetrahydrofuran and 1,4-dioxane) to remove the solvent which has been used in the reaction and in the subsequent washing step. The resultant product is then subjected to hydrolysis with hot water to obtain titanyl phthalocyanine.
Titanyl phthalocyanine as synthetically prepared above is poured into 1 to 100 times (preferably from 3 to 60 times) of its weight of concentrated sulfuric acid having a concentration of from 70 to 100% (preferably from 90 to 97%) at a temperature of from -20° C. to 100° C. (preferably from 0° to 60° C.) to form a solution or a slurry. The resulting solution or slurry is then poured into a solvent to precipitate titanyl phthalocyanine crystals which are isolated by filtration.
The solvent which can be used for precipitation according to the present invention is selected from an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and water, a mixed solvent of an aromatic solvent and water, and a mixed solvent Of an alcohol solvent and an aromatic solvent with or without water. Examples of suitable alcohol solvents are those having-up to 5 carbon atoms such as methanol and ethanol. Examples of suitable aromatic solvents are aromatic hydrocarbons such as benzene, toluene, and xylene; aromatic nitro compounds such as nitrobenzene; aromatic halogen compounds such as monochlorobenzene, dichlorobenzene, trichlorobenzene, and chloronaphthalene; and phenol. In using the mixed solvent, the alcohol solvent/water volume ratio is less than 100/0 to 10/90, and preferably from 80/20 to 40/60; the aromatic solvent/water volume ratio is less than 100/0 to 1/99, and preferably from 60/40 to 5/95; and the alcohol solvent/aromatic solvent volume ratio is less than 100/0 to more than 0/100, preferably from 90/10 to 50/50 when water is absent, and the alcohol solvent/aromatic solvent volume ratio is from 1/99 to 99/1 when Water is present and the volume ratio of the total of the alcohol solvent and the aromatic solvent to water is from 90/10 to 10/90, preferably from 80/20 to 40/60.
The amount of the above-described solvent to be used ranges from 2 to 50 times, preferably from 5 to 20 times, the weight of the concentrated sulfuric acid solution or slurry.
The isolated crystal may further be subjected to a solvent treatment to allow the crystal to grow to a desired size (e.g., 0.05 to 0.1 μm) and also to eliminate impurities from the crystal.
The solvent treatment can be carried out by adding the isolated titanyl phthalocyanine crystal to an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and an aromatic solvent, or a mixed solvent of an alcohol solvent and/or an aromatic solvent and water, followed by stirring or milling at a temperature of from room temperature to 100° C., preferably from 30° to 80° C., for a period of from 10 minutes to 5 hours, preferably from 10 minutes to 4 hours.
Examples of alcohol solvents and aromatic solvents used for the purpose are the same as those described above, and methanol, ethanol, benzene, toluene, monochlorobenzene, dichlorobenzene, trichlorobenzene, phenol or the like is generally used. In using the mixed solvent wherein the alcohol solvent and the aromatic solvent do not co-exist, the alcohol/water volume ratio is less than 100/0 to 10/90, and preferably less than 100/0 to 50/50; and the aromatic solvent/water volume ratio is less than 100/0 to 1/99, and preferably from 60/40 to 3/97. In the case of using the mixed solvent of an alcohol solvent, an aromatic solvent and water, the alcohol solvent/aromatic solvent volume ratio is from 1/99 to 99/1 and the volume ratio of the total of the alcohol solvent and the aromatic solvent to water is from 100/0 to 1/99 and preferably from 60/40 to 3/97.
The titanyl phthalocyanine crystal obtained by the process of the present invention is a novel crystal showing at least one diffraction peak at a Bragg angle (2θ±0.2) of 27.3°, and the crystal has other diffraction peaks at 24.0°, 18.0°, and 14.3°. Since it has photosensitivity in a wavelength region extending to the longer side, it is very useful as a photoconductive material of an electrophotographic photoreceptor of, for example, a printer utilizing a semi-conductor laser as a light source.
The present invention is now illustrated in greater detail with reference to Examples, but it should be understood that the present invention is not deemed to be limited thereto. All the parts, percents and ratios are by weight unless otherwise indicated. Examples, X-ray diffraction was measured with an X-ray diffractometer RAD-RC manufactured by Kabushiki Kaisha Rigaku, under the conditions given below:
Power of X-ray generator: 18 KW
Target: Cu
Wavelength of characteristic X-rays (CuK): 1/54050 angstrom
Voltage: 40.0 KV
Current: 300.0 mA
Initiation angle: 5.00 degrees
Termination angle: 40.00 degrees
Step angle: 0.020 degrees
SYNTHESIS EXAMPLE
Synthesis of Titanyl Phthalocyanine
To 20 parts of 1-chloronaphthalene were added 3 parts of 1,3-diiminoisoindoline and 1.7 parts of titanium tetrabutoxide, and the mixture was allowed to react at 190° C. for 5 hours. The reaction product was collected by filtration and washed successively with aqueous ammonia, water, and acetone to obtain 4.0 parts of titanyl phthalocyanine.
A powder X-ray diffraction pattern of the resulting titanyl phthalocyanine crystal is shown in FIG. 7.
EXAMPLE 1
Two parts of the titanyl phthalocyanine obtained in the Synthesis Example were dissolved in 100 parts of 97% sulfuric acid at 5° C., and the solution was poured into an ice-cooled mixed solvent consisting of 400 parts of methanol and 400 parts of water. The precipitated crystal was collected by filtration, washed successively with methanol, dilute aqueous ammonia and water, and dried to obtain 1.6 parts of a titanyl phthalocyanine crystal.
A powder X-ray diffraction pattern of the resulting titanyl phthalocyanine crystal is shown in FIG. 1.
EXAMPLE 2
Two parts of the titanyl phthalocyanine crystal obtained in the Synthesis Example were dissolved in 60 parts of 97% sulfuric acid at 5° C., and the solution was poured into an ice-cooled mixed solvent consisting of 400 parts of methanol and 400 parts of water. The precipitated crystal was filtered, washed successively with methanol, dilute aqueous ammonia, and water, and dried to obtain 1.5 parts of a titanyl phthalocyanine crystal. A powder X-ray diffraction pattern of the resulting titanyl phthalocyanine crystal is shown in FIG. 2.
EXAMPLE 3
Two parts of the titanyl phthalocyanine crystal obtained in the Synthesis Example were dissolved in 100 parts of 97% sulfuric acid at 5° C., and the solution was poured into an ice-cooled mixed solvent consisting of 400 parts of toluene and 400 parts of methanol. The precipitated crystal was filtered, washed successively with methanol, dilute aqueous ammonia, and water, and dried to obtain 1.6 parts of a titanyl phthalocyanine crystal. A powder X-ray diffraction pattern of the resulting titanyl phthalocyanine crystal is shown in FIG. 3.
EXAMPLE 4
Two parts of the titanyl phthalocyanine crystal obtained in the Synthesis Example were dissolved in 100 parts of 97% sulfuric acid at 5° C., and the solution was poured into an ice-cooled mixed solvent consisting of 720 parts of water and 80 parts of monochlorobenzene. The mixture was stirred in an oil bath at 50° C. for 1 hour, followed by filtration. The collected crystal was washed successively with methanol, dilute aqueous ammonia, and water to obtain 0.8 part of a titanyl phthalocyanine crystal. A powder X-ray diffraction pattern of the resulting titanyl phthalocyanine crystal is shown in FIG. 4.
EXAMPLE 5
One part of the titanyl phthalocyanine crystal obtained in Example 1 was stirred in a mixed solvent consisting of 10 parts of water and 1 part of monochlorobenzene at 50° C. for 1 hour, followed by filtration. The solid was washed successively with methanol and water to obtain 0.9 part of a titanyl phthalocyanine crystal. An X-ray diffraction pattern of the resulting crystal is shown in FIG. 5.
EXAMPLE 6
One part of the titanyl phthalocyanine crystal obtained in Example 1 was stirred in 10 parts of methanol at 50° C. for 1 hour, followed by filtration. The solid was washed successively with methanol and water to obtain 0.9 part of a titanyl phthalocyanine crystal. An X-ray diffraction pattern of the resulting crystal is shown in FIG. 6.
APPLICATION EXAMPLE
One part of the titanyl phthalocyanine crystal obtained in Example 1 was mixed with 1 part of polyvinyl butyral ("ESLEC BM-1", produced by Sekisui Chemical Co., Ltd.) and 100 parts of cyclohexanone, and the mixture was dispersed in a paint shaker together with glass beads for 1 hour. The resulting coating composition was coated on an aluminum support by dip coating and dried by heating at 100° C. for 5 minutes to form a 0.2 μm-thick charge generating layer.
In 20 parts of monochlorobenzene were dissolved 2 parts of a compound of formula: ##STR2## and 3 parts of poly(4,4-cyclohexylidenediphenylenecarbonate) of formula: ##STR3## and the resulting coating composition was coated on the charge generating layer by dip coating and dried by heating at 120° C. for 1 hour to form a 20 μm-thick charge transporting layer.
The resulting electrophotographic photoreceptor was charged to -6 kV with a corona discharge in an ambient-temperature and ambient-humidity condition (20° C., 50% RH) by means of an electrostatic copying paper analyzer ("EPA-8100" manufactured by Kawaguchi Denki K.K.) and then exposed to monochromatic light (800 nm) isolated from light emitted from a tungsten lamp by a monochromator at an irradiance of 1 μW/cm 2 . The exposure amount E 1/2 (erg/cm 2 ) necessary for the surface potential to be reduced to 1/2 the initial surface potential V 0 (V) was measured. Then, the photoreceptor was irradiated with tungsten light of 10 lux for 1 second, and a residual potential V R was measured. Further, the above-described charging and exposure were repeated 1000 times, and the same measurements of V 0 , E 1/2 , and V R were made. As a result, V 0 =-840 V; E 1/2 =1.3 erg/cm 2 ; and V R =0 V. After the 1,000-time repetition of charging and exposure, V 0 =-830 V; E 1/2 =1.3 erg/cm 2 ; and V R =0 V.
REFERENCE EXAMPLE
For comparison, an electrophotographic photoreceptor was prepared in the same manner as in the Application Example, except for using the titanyl phthalocyanine crystal having a powder X-ray diffraction pattern of FIG. 7 as obtained in the Synthesis Example as a charge generating material. The comparative photoreceptor was evaluated in the same manner as in Application Example. As a result, V 0 =-780 V; E1/2=4.1 erg/cm 2 ; and V R =10 V. After the 1,000-time repetition of charging and exposure, V 0 -750 V; E 1/2 =3.8 erg/cm 2 ; and V R =15 V. The comparative photoreceptor thus proved inferior to that prepared in the Application Example.
As described above, according to the present invention, a stable crystal of titanyl phthalocyanine showing at least one diffraction pattern at a Bragg angle (2θ±0.2) of 27.3° can be obtained with ease through a very simple operation. The titanyl phthalocyanine crystal obtained by the present invention is very useful as a photoconductive material of electrophotographic photoreceptors used in printers utilizing a semiconductor laser as a light source. The electrophotographic photoreceptors using the titanyl phthalocyanine crystal of the present invention exhibit high sensitivity and excellent durability on repeated use.
While the invention has been described in detail and with reference to specific examples thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | A process for preparing a titanyl phthalocyanine crystal showing at least one diffraction peak at a Bragg angle (2θ±0.2) of 27.3° is disclosed, which comprises dissolving or suspending titanyl phthalocyanine in concentrated sulfuric acid to form a solution or a slurry and diluting the solution or slurry with an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and water, a mixed solvent of an aromatic solvent and water, or a mixed solvent of an alcohol solvent and an aromatic solvent with or without water thereby to precipitate a crystal, and, if desired, treating the precipitated crystal with an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and an aromatic solvent or a mixed solvent of an alcohol solvent and/or an aromatic solvent and water. The resulting titanyl phthalocyanine crystal exhibits high photosensitivity and excellent durability as a photoconductive material of an electrophotographic photoreceptor. | 2 |
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
The present invention relates generally to a regenerative heat exchange system for transferring heat from one fluid to another and pertains more particularly to a shell and tube system which is capable of transferring heat between electrolytic or corrosive fluids. The present invention is particularly suited for marine use such as in coastal installations, on drilling platforms, or aboard marine vessels where sea water is used as the cooling fluid.
In conventional marine duty heat exchangers, where sea water is used as the cooling fluid, the tube bundles are constructed of copper-alloy tubes and are mounted within a tubular steel shell. Steel inlet and outlet tube sheets are coupled to the inlet and outlet ends, respectively, of the shell by appropriate flanges and are correspondingly apertured to receive and support the ends of the tubes. Cooling seawater passes through the inlet tube sheet and into the tubes, whereupon heat is transferred thereto by recirculating a heated fluid through the shell.
The steel, copper alloy and other materials presently used in the construction of marine duty heat exchangers are heavy and subject to both corrosion and erosion. Copper alloy tubes are particularly subject to erosion at high fluid velocities. Prior art heat exchangers rely on the maintenance of non-turbulent flow conditions to prevent erosion of the tubes and other wetted components. For example, if sea water is pumped through a 3/4" diameter tube at a flow velocity through the center of the tube of approximately 8 ft/sec, laminar flow conditions can be established. Under laminar flow conditions, a thin layer of fluid at the tube walls is maintained at zero velocity, thereby eliminating the problem of erosion.
Unfortunately, however, the same thin layer of fluid at the tube walls which prevents erosion also results in a higher convective resistance and thus impedes heat transfer between the fluids. Since the turbulent flow regimes obtained at fluid velocities of 25 ft/sec or more are required for optimum heat transfer between the fluids, the reduction in erosion achieved by reducing fluid velocity to maintain laminar flow in the tubes comes at the direct expense of heat transfer efficiency.
Another disadvantage of reducing the flow rate of fluid within the pipes is a heightened risk of fouling the sea water side of the inlet tube sheet with biological material. Formations of scale deposits on the inlet side of the heat exchanger are also a problem associated with low flow rates.
It is therefore an object of the present invention to provide an erosion and corrosion resistant heat exchanger apparatus which also provides high transfer efficiency.
It is another object of the present invention to provide a heat exchanger apparatus which can be readily retrofitted into existing installations.
It is yet another object of the present invention to provide a heat exchanger which is resistant to fouling and the formation of scale deposits.
It is still another object of the present invention to provide a method of repairing the tubes within a heat exchanger constructed in accordance with the present invention.
It is also an object of the present invention to eliminate problems caused by tube vibrations at the tube sheets and by temperature gradients within the shell.
SUMMARY OF THE INVENTION
The apparatus for exchanging heat between two fluids comprises a plurality of elongated tubes for carrying a first fluid. Each tube has a first end and a second end and is formed of a first corrosion resistant and erosion resistant material. A first transverse member supports the first end of each tube by defining a plurality of apertures for receiving ends of the tubes and is formed of a corrosion and erosion resistant material. A second transverse member supports the second end of each tube by defining a plurality of apertures for receiving ends of the tubes and is formed of a corrosion and erosion resistant material.
The corrosion and erosion resistant material of the tubes may comprises titanium, carbon fibers in an epoxy resin matrix, or a sintered-alpha silicon carbide ceramic. The corrosion resistant material of the transverse members comprises a cotton reinforced phenolic resin.
The first end of each tube is secured within a respective aperture of the first transverse member by an epoxy adhesive. A plurality of adaptors receive ends of the tubes at one end and engages an aperture of the second transverse member at the other. Each adaptor is formed of a thermally insulating, erosion and corrosion resistant material and comprises a tubular member having an outer surface and means for creating a seal between the outer surface and the second transverse member. The outer surface of the adaptor defines an annular groove for receiving a seal creating means such as an O-ring. The outer surface of each adaptor is adhesively bonded to an interior surface of a tube.
Intermediate support means disposed between adjacent tubes are formed of a material having corrosion and erosion resistance properties and define a serpentine flow path for the fluid flowing between the tubes.
The heat exchanger apparatus further comprises a shell means for housing the tubes for establishing a flow path for a second fluid. The shell means comprising a first tubular member concentrically disposed within a second tubular member. Each of the tubular members has an inlet end region, an outlet end region and an intermediate region therebetween. Each of the tubular members is formed of a thermally insulating, erosion and corrosion resistant material such as a silica reinforced phenolic resin material. The first and second tubular members each have walls defining interior and exterior surfaces. The second tubular member has a uniform inner diameter. The first tubular member has an outer diameter at its intermediate region equal to the inner diameter of the second tubular member but has reduced outer diameters at its inlet and outlet end regions such that the interior surface of said second tubular member and the exterior surface of said first tubular member define annular inlet and outlet chambers therebetween. The annular inlet and outlet chambers substantially surrounds a portion of the exterior surface of the inner tubular member. The shell means also defines an inlet opening through the tubular members for receiving a second fluid therethrough, the annular inlet chamber being in fluid communication with the inlet opening at a position located adjacent the first transverse member, and an outlet opening through the tubular members, for discharging the second fluid therethrough, the annular outlet chamber being in fluid communication with the outlet opening. The periphery of the first tubular member defines a plurality of apertures within the annular inlet chamber for admitting the second fluid therethrough and a plurality of apertures within the annular outer chamber for discharging the second fluid therethrough.
Another embodiment of the heat exchanger apparatus utilizes an alternate means of supporting the ends of the tubes and comprises a plurality of elongated tubes for carrying a first fluid, each tube having a first end and second end and being formed of a thermally conductive, corrosion resistant and erosion resistant material and a shell for housing the elongated tubes and establishing a flow path for a second fluid. The shell is formed of a thermally insulating, corrosion and erosion resistant material.
First support means are coupled to the inlet end of the shell for supporting the first end of each tube and define a barrier between the first fluid and the second fluid. Second support means are coupled to the outlet end of the shell for supporting the second end of each tube and for defining a barrier between said the first fluid and said second fluid. The first and second support means are formed of a thermally insulating, corrosion and erosion resistant material, and each support means comprises first and second plate members and means for sealing between the first and second fluids. The first plate members define a first group of apertures for receiving ends of the tubes and the sealing means, and the second plate members define a second group of apertures for alignment with said first group.
The sealing means of the first plate member comprises a plurality of tubular members having an inner diameter corresponding to the outer diameter of the tubes and a plurality of ring members, wherein each tubular member is disposed between a ring member and one of said second plate members. The apertures of the second group have a smaller diameter than the apertures of the first group, such that an edge surface of each tubular member engages a surface of said second plate member in abutting relation.
First and second tubular head members are coupled at one end to the first and second support means, respectively and are covered at the other end by a cover plate. The head members and covers are formed from a thermally insulating, corrosion resistant and erosion resistant material and define respective inlet and outlet chambers for the first fluid.
A method of repairing a leaking heat exchanger tube formed of carbon fibers in an epoxy resin matrix comprises the steps of removing a tube section having a leak therein from said heat exchanger, cutting the tube into first and second sections at the site of said leak, providing a first tubular segment having similar internal and external diameters to the tube, removing a longitudinal section of the first tubular segment and applying a bonding agent to an outer surface of said first segment, inserting a portion of the first tubular segment into one of the first or second tube sections, inserting the remaining portion of the first tubular segment into the other of the tube sections until the first and second sections are in abutting contact to form a tight joint, providing a second tubular segment having similar internal and external diameters to the first tubular segment, longitudinally cutting the second tubular segment along its entire length, expanding the second tubular segment to achieve an inner diameter slightly greater than the external diameter of the leaking tube, sliding the second tubular segment into a position overlying the tight joint and bonding the second tubular segment thereto.
Where the leak is not severe, an alternate method of repair comprises the steps of removing a leaking tube having a leak therein from said heat exchanger, providing a first tubular segment having the same internal and external diameters as the leaking tube, longitudinally cutting the first tubular segment along its entire length, expanding the first tubular segment to achieve an inner diameter slightly greater than the external diameter of the leaking tube, and sliding the first tubular segment into a position overlying the leak and bonding the first tubular segment thereto.
Although the apparatus has been described in connection with use of sea water as the cooling fluid, it is contemplated that the exchanger of the present invention would also be adapted for use in chemical processes such as for transferring heat to or from corrosive chemicals.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a heat exchanger apparatus constructed in accordance with the present invention;
FIG. 2 is a partial elevation view of an inlet tube sheet constructed in accordance with the present invention;
FIG. 3 is a cross sectional view, taken across line III--III of FIG. 2, of the inlet tube sheet shown in FIG. 2;
FIG. 4 is a partial elevation view of an outlet tube sheet constructed in accordance with the present invention;
FIG. 5 is a cross sectional view, taken across line V--V in FIG. 4, of the outlet tube sheet;
FIG. 6 is a cross sectional view, showing the interconnection of a tube to the inlet and outlet tube sheets in accordance with the present invention;
FIG. 7 is a partial cross sectional view showing a modified construction of the inlet tube sheet and an adapter for connecting the tube thereto;
FIG. 8 is a cross sectional view of the tube bundle and shell showing an arrangement of tube supports between the tubes;
FIG. 9 is a plan view of the inner shell constructed in accordance with the present invention;
FIG. 10 is a plan view of the outer shell constructed in accordance with the present invention;
FIG. 11 is a plan view of a first baffled tube support plate for use in the heat exchanger of the present invention;
FIG. 12 is a plan view of a second baffled tube support plate for use in the heat exchanger of the present invention;
FIG. 13 is a partial cross sectional view of a modified tube sheet design for use in the heat exchanger of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the invention embodied therein comprises an apparatus for exchanging heat between a first fluid and a second fluid, and in particular for transferring heat from a recirculated fluid to a corrosive or electrolytic fluid such as sea water, salt water, or brackish water.
Heat exchanger 10 includes a tubular shell 12 comprising an inner tubular member 14 and an outer tubular member 16 and having an inlet end 18 and an outlet end 20. Shell 12 houses a tube bundle 22 which comprises a plurality of parallel, spaced tubes 24 and a plurality of tube supporting members 26 for maintaining the tubes in spaced longitudinal relationship. Inlet and outlet tube sheets, 28 and 30, respectively, receive and support opposite ends of the tubes 24. A tubular head 32 is coupled by tie rods 34 to each tube sheet by a centrally apertured cover plate 36 to form inlet and outlet chambers 38 and 40.
In order to permit utilization of a corrosive or electrolytic cooling fluid, the tubes 24 are constructed of a corrosive resistant metal, metal alloy, fiber reinforced polymer matrix, or ceramic material having appropriate thermal conductivity characteristics. Examples of acceptable materials include titanium, sintered-alpha silicon carbide ceramics, and carbon fiber polymer resin matrix materials. Preferably, the tubes are made from a material comprising filament-wound carbon fibers in an epoxy resin matrix. Tubes constructed of such material provide superior erosion resistance, outstanding corrosion resistance and low weight, yet also demonstrate adequate thermal conductivity and burst/collapse pressure strength.
The embodiment of the inlet tube sheet 28 shown in FIG. 2 is constructed for supporting the tubes at the inlet end of the shell. Sheet 28 comprises a plate 42 having an outer face 43 which faces the incoming fluid and which preferably has an annular recess 44 formed therein. Within the area circumscribed by the annular recess 44 are a plurality of apertures 46 through plate 42 for receiving respective inlet ends of the tubes 24. As best shown in FIG. 3, each aperture is divided into two sections, 46a and 46b. Section 46b is of a diameter corresponding to the external diameter of tubes 24 and is adapted to receive and support the same. Section 46a opens to outer face 43 and is of a reduced diameter, thereby defining a step or abutment 48 against which the end of a tube 24 is seated.
With reference now to FIG. 4, the outlet tube sheet 30 will now be described. Tube sheet 30 is constructed for supporting the tubes at the outlet end of the shell and comprises a plate 50 having an outer face 51 with an annular recess 52 formed thereon. Within the area circumscribed by the annular recess 52 are a plurality of apertures 54. As shown in FIG. 5, the apertures 54 in sheet 30 are preferably of a constant diameter.
With reference now to FIG. 6, the connection of the tube ends to the respective tube sheets will now be described. The inlet tube sheet 28 defines a fixed end of the tube bundle, and the inlet ends of tubes 24 are sealingly maintained within the apertures 46 therein by any conventional manner. Preferably, the tube ends are adhesively bonded within aperture sections 46b by an epoxy adhesive 56 to form a fixed joint therewith.
The second or outlet tube sheet 30 defines a free end of the tube bundle. Each aperture 54 is dimensioned to receive a respective tube mounting adapter 57. Each tube mounting adapter 57 is substantially cylindrical and comprises an axial bore 58 and two annular recesses 59a, 59b on its exterior surface. At one end of the tube mounting adapter 57, the axial bore 58 includes an entry portion 60 which is received in the outlet end of a tube 24. In use, the end of the adaptor defining the entry portion 60 is adhesively bonded within the outlet end of a tube 24 and the other end of the adapter is positioned within an aperture 54 of the outlet tube sheet. To provide a fail safe sealing between the two fluids, O-rings 62 are inserted into annular recesses 59a and 59b for engagement with the interior wall of an aperture 54. Retaining rings 63 may be inserted on opposite sides of each O-ring.
The shell, tube sheets, and tube adaptors may be fabricated from any materials having sufficient thermal insulating, erosion and corrosion resisting and good machinability properties. The tube adapter material must also allow thermal expansion and contraction of the tubes through the tube sheets. Although the preferred material for the shell, tube sheets, and adaptors is a glass or cotton fiber reinforced phenolic resin, other glass or carbon-fiber reinforced polymers, such as epoxy, polyamide, or polyimide resins are also suitable. These materials can permit much higher seawater velocities than conventional copper-nickel alloys, can provide pressure ratings of at least 150 psi at 200° F., dampen vibration and flow generated noise, help to reduce magnetic signatures, and reduce overall assembly weight by over 50 percent.
With reference to FIG. 1, the heads 32 and covers 36 will now be described. Each cover 36 is essentially a circular plate having a central aperture 65 and a plurality of bores for receiving tie rods 34. Each cover 36 also include an annular recess which is dimensioned to receive one end of a tubular head 32. A nitrile rubber gasket 64 is seated within the recess to provide a tight, leakage resistant seal between a first end of the head and the cover. When completely assembled in the manner shown in FIG. 1, the second end of the tubular head 32 is received in a gasketed annular recess 44 or 52 of the tube sheets and the components are held together by stainless steel tie rods to form the inlet and outlet chambers, 38 and 40, respectively.
Although the present invention decreases fouling by permitting high fluid flow rates through the inlet chamber, it is possible to further reduce fouling within the inlet chamber by coating the outer face of the inlet tube sheet and the interior of the head with a copper or organometallic antifoulant coating. Preferably, a copper alloy coating 66 is flame sprayed onto all surfaces within the inlet chamber.
With reference now to FIG. 7, an alternate inlet tube sheet and a means for securing the inlet tube end thereto will now be described. Modified inlet tube sheet 28' is constructed in a similar manner to and using the same materials as the embodiment shown in FIG. 2. However, in lieu of having a reduced diameter section for seating the inlet end of a tube, each aperture 46' is threaded and receives an externally threaded inlet adapter 68. Each inlet adapter acts as a funnel for the incoming fluid and includes an axial bore 70 having a fluted inlet section 70a into which the incoming fluid is directed. An outlet section 72 of the axial bore receives the end of the tube. Any conventional means of joining the tube end to the inlet tube sheet may be used to prevent leakage between the fluids. For example, a suitable adhesive may be used at the joint between the tube wall and the interior of the inlet adapter. If desired, the interior of the adapter may have a stepped diameter and a nitrile rubber gasket may be used at the interface between the end of the tube and the abutment formed by the decreased diameter section of the bore.
With reference now to FIG. the tubes 24 are preferably spaced from one another along their lengths by a plurality of tube support members 26. Each tube support member 26 preferably comprises an elongated rod 26a having a plurality of projecting supports 26b disposed at spaced intervals therealong. Spacing of the supports permits serpentine flow of fluid around the tubes to enhance thermal conductivity.
The projecting supports 26b may be integrally formed during manufacture of the rod 26a or may be provided with a central bore and adhesively bonded to the rod in a separate operation. The tube support members 26 may be manufactured from any material having suitable corrosion resistance and heat strength. Preferably, however, they are formed from a thermoplastic material such as glass reinforced polyamide-imide resin.
Since the purpose of the tube support members 26 is to engage and support the surfaces of the tubes 24, it should be understood that the projecting supports 26b may be of any geometrical configuration. For example, they may have a circular cross section, such as a cylinder or sphere, or they may have a polygonal cross section. The surface of supports 26b may also be provided with recesses corresponding to the external contour of the tubes to provide support over a larger area and thereby minimize radial stresses in the tube. In the preferred embodiment, however, spherical supports are used. A cross section of the tube bundle showing a possible arrangement of tubes and rod support members is shown in FIG. 8.
With reference to FIGS. 9, and 10, shell 12 comprises an inner tubular member 14 and an outer tubular member 16. As shown in FIG. 9, tubular member 14 comprises an intermediate region 14b having an outer diameter corresponding to the inner diameter of tubular member 16. At both the inlet and outlet ends, however, the tubular member 14 has a reduced outer diameter region 14a. A plurality of apertures 15 are formed at each end of tubular member 14 in the reduced diameter regions.
Preferably, the apertures 15 are provided as arcuate recesses along the edges of the inner tubular member. However, they may be provided in any geometric shape and at any location within the region 14a.
As shown in FIG. 10, the outer tubular member has a uniform diameter and inlet and outlet openings, 19a and 19b respectively, for admitting and discharging the recirculated fluid into the shell. When inner tubular member 14 is concentrically mounted within the outer tubular member 16 as shown in FIG. 1, the area between regions 14a and the outer tubular member 16 define respective annular flow diverting chambers 17a and 17b. Fluid entering through the inlet 19a is directed first into the annular chamber 17a and then through the apertures 15, thereby eliminating any vibrations of the tubes which would otherwise be caused by direct impingement on the tubes by the incoming fluid. Temperatures of the fluid within the shell are also made more uniform by diffusing the flow over the entire circumference of the shell. After circulating through shell 12, fluid discharges from apertures 15 into annular chamber 17b and then from outlet opening 19b.
A spaced arrangement of aligned baffle plates positioned within the shell might also be used instead of the support member arrangement shown in FIG. 1. FIG. 11 shows a disk shaped baffle plate 70 having apertures 72 for receiving and supporting sections of tube 24. Circumferential recesses 74 along the periphery of the baffle plate 70 permit fluid to pass through the shell without excessive reduction in the flow rate.
FIG. 12 shows an annular baffle plate 80 having a plurality of receiving apertures 82 and a large central opening 84. By alternating between disk shaped and toroidally shaped baffles within the shell, adequate support of the tubes 24 can be achieved while maintaining high velocity, serpentine flow through the shell. The baffle plates may be manufactured from any corrosion and erosion resistant material. Preferably, the baffle plates are constructed from a cotton reinforced phenolic material.
With reference now to FIG. 13, a modified tube sheet construction which can be used at both the inlet and outlet ends of the tube bundle will now be described. The modified tube sheet 90 is comprised of two laminar sections, 91 and 92. Inner section 91 defines a first group of apertures such that each aperture has a diameter slightly greater than the outer diameter of the tubes and receives and supports the ends of the tubes 24 therein. A tubular segment 93 is positioned on the end of each tube to maintain the tubes centrally within the apertures of inner section 91. A plurality of sealing means such as an alternating arrangement of O-rings 94 and retaining rings 95 are also positioned on the tubes and these are seated within the first group of apertures adjacent tubular segment 93 and abutment 96 to prevent leakage between the respective fluids.
Outer section 92 defines a second group of apertures which are in alignment with the first group. The edges of tubes 24 and segments 93 surrounding them abut against the surface of outer section 92 which faces the shell.
When the tubes 24 are constructed of slightly flexible materials such as those comprising carbon filaments in an epoxy resin matrix, they may be easily repaired in the field without completely removing them from the heat exchanger. To do so, the tube affected is positioned to expose the damaged or leaking section. Where only minor damage exists, a single tubular segment of the same cross sectional dimensions as and formed of the same material as the tube can be used to repair it. A longitudinal cut is made in the segment, a suitable adhesive is applied to the surface of the damaged tube or to the interior of the segment itself and the segment is slid into position over the damaged area. Where more extensive damage exists two segments can be used for repair of the tube. This type of repair requires a transverse cutting of the tube at a site adjacent the damaged area. An exterior tube repair segment is prepared in a manner identical as that explained above. An interior tube repair segment is prepared by removing a narrow, longitudinal section of material therefrom. This is done by making two closely spaced longitudinal cuts along the entire length of a tubular segment. Once the interior repair segment is prepared, it is compressed by external pressure and a portion of it is inserted into one of the tube sections at the site of the cut. An adhesive bonding agent should be applied to the interior of the tube and the exterior of the interior repair segment. The other end of the interior repair segment is compressed, treated with adhesive, and then inserted into the other tube. Thereafter, the two tube sections can be pushed together to create a close fitting joint and the first segment can be slid into position over the joint. Preferably, the location of the slits in the interior repair section is oriented 180 degrees from the slit in the exterior repair section. Once the adhesive has dried, the repaired tube can be slid back into position within the tube bundle.
As will be apparent to those of ordinary skill in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims. | A heat exchanger for use in exchanging heat between corrosive or electrolc fluids has wetted components which are comprised of corrosion and erosion resistant materials. The use of corrosion and erosion resistant tube sheets, shell, and tubes permits the heat exchanger to operate at high flow rates to produce turbulent flow through the inlet tube sheet and tubes, thereby optimizing transfer efficiency between a corrosive fluid in the tubes and the regenerated fluid pumped through the shell.
In order to eliminate problems of temperature gradient and vibrations at the area where the tubes are joined to the inlet tube sheet, the shell is comprised of an inner and outer shell section to form annular flow diverting chambers therebetween. The inner shell section of each chamber is apertured so that flow is diffused over the entire surface, thereby avoiding direct impingement of fluid over the tubes. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority from provisional application Ser. No. 60/652,375, filed Feb. 11, 2005.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the field of offshore subsea oil and gas drilling and production operations. Specifically the invention relates to a hydraulically and/or mechanically driven junction plate actuator suitable for use in connecting and/or disconnecting a dynamic junction box half to a fixed junction box assembly.
2. Description of the Prior Art
Disconnectable hydraulic and electrical junction boxes are utilized in many subsea control and intervention applications. These applications include subsea blowout preventer (B.O.P.) stacks, production trees, production tree installation and workover systems, manifold systems, and interface systems. The applications may include direct control interfaces where remote installation is necessary and back up (intervention) to a main control module in the event of system failure.
Current disconnectable junction box assemblies consist of a fixed plate containing both checked and balanced hydraulic couplers and in some cases wet make/break electrical couplers. The fixed plate is mounted to the junction box assembly. A particular coupler can interface to the function to be controlled via hard pipe, hydraulic hose, or electrical pigtails.
The matching or dynamic plate containing the male or female coupler half interfaces to the fixed plate and is locked in place providing communication from the dynamic plate umbilical or cable through the couplers or electrical connector. In some cases, this mating interface is accomplished by utilizing a remote operated vehicle (R.O.V.) to manipulate the dynamic junction half to the assembly receiver interface via a flying-lead assembly.
Prior art systems employed for installation and makeup of a junction plate assemblies have consisted of a keyed female receiver funnel and matching male plug assembly, which is keyed and locked into the female receiver via the R.O.V. tooling end effector or coupling which rotates the locking dogs or similar detent mechanism in place. In turn, a mechanical screw, also driven by the R.O.V. tooling end effector, provides the makeup and breakout of the dynamic junction plate half to the fixed junction plate half.
The functionality of the prior art system described above is limited. For example, there are cases where hydraulic extend/retract functionality is desired. In such cases, hydraulic actuation to make and break the junction box halves provides the means to disconnect and retract the dynamic junction box half from the fixed assembly without intervention from the remote operated vehicle (R.O.V.). This may be advantageous in operations where the R.O.V. is being used for alternate tasks or is on surface for servicing or repair.
Additionally, there are distinct advantages in some applications in having a manual mechanical override function in the case of hydraulic system failure. This provides a redundancy provision in the method of operation providing the means for both hydraulic and mechanical actuation. Prior art systems do not provide a combined hydraulic and manual mechanical override capability, and are thus limited in functionality.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side cross sectional view of a preferred embodiment of the invention.
FIG. 2 a is a side cross sectional view of the preferred embodiment of FIG. 1 with the piston full stroked in the direction of the junction plate or extended position.
FIG. 2 b is a side cross sectional view of the preferred embodiment of FIG. 1 with the piston full stroked in the direction of the proximal section of the drive spline or retracted position.
FIG. 3 a is an isometric view of a preferred embodiment of the present invention.
FIG. 3 b is an exploded isometric view of a preferred embodiment of the present invention.
FIG. 4 is a side view of an embodiment of the invention where an R.O.V. equipped with a bucket is coupled to the coupling member of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the invention is directed to a hydraulically actuated junction plate with integral mechanical override. In a preferred embodiment, the assembly comprises of a hydraulic actuating cylinder, which is designed with a hollow piston rod equipped with a machined screw profile in one (1) end. The rod bore contains a mechanical screw with an acme thread profile upset allowing for the screw to rotate through the piston bore. In turn, the mechanical screw is machined with a broached spline profile (female) in one end to accept a male spline which is allowed to slip-in and out-of the screw spline bore creating a slip-joint action between the screw and the male spline.
In a preferred embodiment, the mechanical screw is arranged with a flange end for attachment to the junction plate half containing the hydraulic and electrical couplers and the female spline end for interface to the male drive spline In a preferred embodiment, the male drive spline 62 is machined with an R.O.V. drive profile nut and is captured in the R.O.V. intervention female receptacle (bucket) 61 designed to accommodate the R.O.V. end effector tooling unit, as shown in FIGS. 3 a , 3 b , and 4 . By rotating the drive spline, the mechanical screw drives both the hydraulic cylinder piston which when bottoms out in the cylinder bore, overrides the hydraulics and drives the junction plate in forward (in) or reverse (out).
In a preferred embodiment, the cylinder piston rod is also equipped with a flange boss containing and anti-rotation rod, which slides in a bushing contained in a flange, which is integral to the cylinder. This alleviates the potential for the piston rod and piston to rotate in the cylinder due to the torque transferred from the screw during rotation.
In a preferred embodiment, the initial application for the junction box assembly relates to a subsea blow out preventer stack discrete hydraulic control pod. The control pod interfaces to the surface control manifold via hydraulic hose bundles containing separate pilot lines. The hose bundle terminates at a fixed junction box at the top of each control pod and is supported by individual hose-to-wireline clamps attached to a wireline. The wireline also attaches to the pod top and is used for running and retrieving each individual pod for repair. During running and retrieving operations, the hose bundle is pulled and spooled on to its storage reel along with the wireline subjecting the hose bundle to damage and in turn rig downtime and in many cases hose bundle replacement cost.
In a preferred embodiment, application of the disconnectable junction box assemblies allows for the existing hose bundle to remain static by clamping it to the marine riser and retrieving the pod independently of the hose bundle.
In a preferred embodiment directed to a B.O.P. stack application, the existing hose bundle terminates at a fixed junction box assembly mounted to the lower marine riser package (L.M.R.P.). In turn, a flexible hose bundle length is run to the disconnectable junction box assembly dynamic (or movable) half.
The flexible hose bundle individual pilot or supply hoses interface with balanced couplings located on the junction plate face. Individual assigned pilot hoses are connected to the hydraulic cylinder ports for operation of the extend/retract functions from the surface unit. The assemblies are adaptable to all existing subsea control pods and systems using discrete hydraulic hose bundle assemblies.
The preferred embodiments described below are depicted in FIGS. 1 , 2 a , 2 b , 3 a , and/or 3 b . In another preferred embodiment, the invention comprises a cylinder 10 having an outer wall 12 having an inner surface 14 and an outer surface 16 , a first fluid region 18 , a first fluid port 20 in the wall at the location of the first fluid region, a second fluid region 22 adjacent to the first fluid region, a second fluid port 24 in the wall at the location of the second fluid region, a longitudinal channel 26 extending through a central radial region the first and second fluid regions, first face 19 at the end of the first fluid region, and a second face 21 at the end of the second fluid region
This embodiment further comprises a first fluid line 30 coupled to the first fluid port, and a second fluid 32 line coupled to the second fluid port. In a preferred embodiment, the first and second faces comprised one or more elastemeric sealing members 31 to provide a fluid seal with a member, such as a piston, which may travel through the longitudinal channel. In a preferred embodiment the elastomeric sealing members are o-rings.
Hydraulic fluid can be injected into either the first or second fluid region through the first or second fluid port and ejected from the other of the first or second fluid region through the respective fluid port. This embodiment of the invention further comprises a piston 34 extending through the central channel of the cylinder and having a distal end 36 protruding beyond either first or second fluid region, a proximal end 38 protruding beyond the fluid region of the cylinder opposite the region beyond which the distal end protrudes, and a threaded central longitudinal channel 40 .
This embodiment of the invention further comprises a diaphragm 42 mounted on the piston and sized such that it extends radially outward from the outer surface of the piston to the inner surface of the cylinder outer wall. The diaphragm comprises a first face 44 defining a boundary of the first fluid region, and a second face 46 defining a boundary of the second fluid region.
In the preferred embodiment shown in FIG. 1 , hydraulic fluid entering the first fluid region through the first fluid port causes the diaphragm and piston to move longitudinally toward the second fluid region. The movement of the diaphragm and piston toward the second fluid region causes hydraulic fluid to exit through the second fluid port and through the second fluid line. In FIG. 2 a , the piston is shown fully extended in the direction of the second fluid region. Conversely, hydraulic fluid entering the second fluid region through the second fluid port causes the diaphragm and piston to move longitudinally toward the first fluid region, thereby causing fluid to exit through the first fluid port and the first fluid line. In FIG. 2 b , the piston is shown fully retracted in the direction of the first fluid region.
The first and second fluid lines can be connected to a source of hydraulic fluid and a valve system of the type known to those skilled in the art such that the injection of hydraulic fluid can be alternated, as a user desires, through either the first fluid line or the second fluid line. Longitudinal movement of the piston and the diaphragm can be reciprocated by alternating which of the first or second fluid line is the hydraulic fluid injection or inlet line, and which of the first or second fluid line is the hydraulic fluid ejection or outlet line. As the diaphragm reciprocates longitudinally, the volume of the first fluid region and the volume of the second fluid region change. The total volume of the first and second fluid region will remains constant. The use of hydraulic fluid injected into either the first fluid region or the second fluid region, as described above, is an embodiment of hydraulic actuation of the present invention.
In a preferred embodiment, the threaded central longitudinal channel of the piston comprises the female threads. This embodiment of the invention further comprises a screw member 50 comprising a threaded region 52 rotatably mounted in the central longitudinal channel of the piston, a distal region 54 extending beyond the distal end of the piston, and a proximal region 56 extending beyond the proximal end of the piston.
In a preferred embodiment, the central longitudinal channel of the piston comprises female threads and the threaded region of the screw member comprises matable male threads. Rotation of the screw member with respect to the piston results in longitudinal movement of the screw member relative to the piston. In such relative motion, the screw member may move longitudinally while the piston remains in a fixed longitudinal position. Alternatively, in such relative motion, the piston may move longitudinally while the screw member remains in a fixed longitudinal position.
The screw member further comprises at least one internally positioned longitudinal spline receptacle 58 , such as a keyway. Such a spline receptacle is shown in FIGS. 3 a and 3 b . In other preferred embodiments, the screw member may contain several longitudinal spline receptacles. In a preferred embodiment, the screw member contains at least two spline receptacles positioned on radially opposite sides of the screw member. In general, increasing the number of spline receptacles makes it easier to align a splined member with the screw member.
The distal region of the screw member is adapted to be connectable to a junction plate half 59 which may contains hydraulic and/or electrical couplers. Such adaptation may be accomplished, in a preferred embodiment, by having a flange member 60 attached to the distal end region of the screw member. In another preferred embodiment, as shown in FIG. 1 , the junction plate half 59 is attached to the flange member 60 .
In a preferred embodiment, the invention further comprises a drive spline 62 having, a distal section 64 inserted in the spline receptacle of the screw member such that rotation of the spline member causes rotation of the screw member, and a proximal section 66 opposite the distal section, comprising a coupling member 68 attached to the end of the proximal section. In a preferred embodiment, the distal section of the drive spline comprises a conical end region.
In a preferred embodiment, the coupling member 68 is a hexagonal head adapted to be received within a hexagonal socket, as shown in FIGS. 3 a and 3 b . Those skilled in the art will be familiar with hexagonal sockets or buckets 61 commonly used on R.O.V.'s 63 that are suitable to be coupled to the coupling member such that the rotation of the socket causes rotation of the coupling member. In FIG. 4 , the coupling member 68 is contained within female receptacle 61 that is attached to the R.O.V. 63 .
In a preferred embodiment, rotation of the coupling member causes rotation of the drive spline, which in turn causes rotation of the screw member, resulting in longitudinal movement of the screw member relative to the piston, as described above. Such longitudinal movement of the screw member results in longitudinal movement of a junction plate attached to the distal region of the screw member. The use of mechanical torque to rotate the coupling member, resulting in the combined rotational and longitudinal movement described above, provides a means for mechanical override and/or operation of the present invention. This mechanical override mode can be used to operate the present invention in the absence of hydraulic fluid pressure. Thus, as explained above, longitudinal movement of the screw member can be achieved by hydraulic actuation, or by rotational movement of the coupling member.
In a preferred embodiment, the invention further comprises a flexible bellows 70 extending between the coupling member and the proximal end of the piston.
The foregoing disclosure and description of the inventions are illustrative and explanatory. Various changes in the size, shape, and materials, as well as in the details of the illustrative construction and/or a illustrative method may be made without departing from the spirit of the invention. | The invention relates to the field of offshore subsea oil and gas drilling and production operations. Specifically the invention relates to a hydraulically and/or mechanically driven junction plate actuator suitable for use in connecting and/or disconnecting a dynamic junction box half to a fixed junction box assembly. | 4 |
FIELD OF INVENTION
This invention relates to plumbing devices and is particularly directed to improved means for blocking floor sink drain openings to prevent passage of large objects, while allowing free flow of fluid therethrough.
As is well known, food preparation kitchens are usually provided with a floor sink having a drain opening which connects to a grease trap or sewer to allow disposal of indirect waste water and the like. Unfortunately, rags, napkins, silverware and other large objects are often washed into the floor sink along with the floor washing water and these objects often get carried into the drain and cause blockage, flooding and other problems. Moreover, the loss of napkins, silverware and the like add significant expense to the operation of the restaurant. Unfortunately, most floor sinks have open drains which are subject to the problems noted above. Some prior art drain grates or screens have been provided which are permanently installed in the drain opening. However, these often become clogged and simply add to the flooding problem. Thus, none of the prior art sink drain screens have been entirely satisfactory.
SUMMARY OF THE INVENTION
These disadvantages of the prior art are overcome with the present invention and an improved floor sink drain screen is provided which positively precludes passage of large objects, while permitting free passage of fluid and which can quickly and easily be removed for cleaning, when desired. In some embodiments, a special, tamperproof locking key may be used to prevent unauthorized disassembly of the installed floor drain screen.
These advantages of the present invention are preferably attained by providing an improved floor sink drain screen lock having expandable means for engaging the walls of a floor sink drain, yet being readily collapsible for quick and easy removal when desired.
Accordingly, it is an object of the present invention to provide an improved floor sink drain screen locking apparatus.
Another object of the present invention is to provide an improved floor sink drain screen lock which positively precludes passage of large objects.
A further object of the present invention is to provide an improved floor sink drain screen lock which positively precludes passage of large objects while permitting free passage of liquids.
An additional object of the present invention is to provide an improved floor sink drain screen lock which positively precludes passage of large objects while permitting free passage of liquids and which can quickly and easily be removed for cleaning, when desired.
Yet another object of the present invention is to provide improved floor sink drain screen locks having expandable means for sealingly engaging the walls of a floor sink drain, yet being readily collapsible for quick and easy removal when desired.
These and other objects and features of the present invention will be apparent from the following detailed description, taken with reference to the figures of the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an upper isometric view of a removable locking floor sink drain screen for enlarged opening embodying the invention.
FIG. 2 is a lower isometric view of an embodiment of the invention.
FIG. 3 is an exploded front view of an embodiment of the invention.
FIG. 4 a is a plan view of an embodiment of the center section of the locking floor sink drain screen.
FIG. 4 b is a plan view of another embodiment of the center section of the locking floor sink drain screen.
FIG. 5 is a plan view of the lower section of the locking floor sink drain screen.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 depicts a locking floor sink drain for an enlarged opening, indicated generally at 10 . An upper grate 12 formed with a central opening 14 is surrounded by a plurality of additional openings 16 through which water or any other liquid can be drained. A middle section 18 has a non-expandable section 19 with an internal flange 32 that supports a plurality of vertical separators 22 . An expandable ring section consists of a number of panels 20 separated by a plurality of slits 21 that permit the panels 20 to be forcefully expanded against the inner surface of a drain pipe (not shown). The vertical separators 22 space the grate 12 from the flange 32 and are themselves spaced apart to permit draining liquid to flow into and through the center cavity of the device and down the drain pipe. Positioners 30 attached to the vertical separators 22 interface with the grate 12 to prevent substantial rotational or sliding movement between the grate 12 and the separators 22 . The separators 22 also position and secure the grate 12 above the middle section 18 .
A hollow tapered section 24 has an outer diameter 36 that is larger than the inner diameter of middle section 18 and incorporates internal structure to form a threaded hole 28 . Threaded hole 28 receives a threaded bolt 26 that extends through the central opening 14 of the grate 12 , through the middle section 18 , and secures the grate 12 to tapered section 24 . When tightened, the threaded bolt 26 pulls the tapered section 24 upward and into the middle section 18 , causing the panels 20 of the middle section to expand against the inner diameter of the drain pipe.
Although depicted as a square plate, the metal grate can be circular, rectangular, or of an irregular shape, depending upon the configuration of the installation environment.
FIG. 2 is a lower isometric view of the drain locking device for an enlarged drain. This view provides some detail of the tapered section 24 , and shows exemplary structure through which threaded hole 28 is formed.
FIG. 3 shows an exploded front view of the locking device of this invention. Threaded bolt 26 may have a head 40 which may be a slotted screw, a hexagonal head, a tamperproof head, or any other suitable means know in the art for tightening or loosening bolt 26 . In a preferred embodiment, grate 23 may be metallic, such as brass or stainless steel, although any suitable corrosion-resistant material of sufficient strength and flexibility will suffice, and will have an indented portion 38 to receive the head 40 of bolt 26 and position it flush with the upper grate surface. The grate 23 is supported by vertical separators 22 , and optionally may be secured by positioners 30 or, in some embodiments, suitable fastening means to hold middle section 18 in a fixed relationship with respect to grate 23 . Vertical separators 22 are supported by an internal flange 32 located within upper non-expandable portion 19 of middle section 18 . The lower portion of middle section 18 is a plurality of panels 20 being separated by slits 21 whereby the panels 20 may be forced apart and outwardly against the interior surface of a drain pipe (not shown).
A frusto-conical tapered section 24 of the device has a threaded through hole 28 that receives threaded bolt 26 . The upper diameter 34 of the tapered section 24 is smaller than the inner diameter of middle section 18 , while the lower diameter 36 of the tapered section is larger than the inner diameter of middle section 18 . As threaded bolt 26 is tightened, tapered section 24 is drawn up against the expandable section 20 of middle section 18 , causing the panels 20 to expand and press against the inner surface of a drain pipe and lock the device into the drain.
FIG. 4 a is a plan view of the middle section 18 of the device of this invention. As viewed from above in FIG. 4 a , vertical separators 22 may have a rectangular cross-section and a positioning knob or fastening means 30 to interface with the grate 12 . Fastening means 30 may assist in maintaining the physical relationship between grate 12 and middle section 18 , and may be positioning knobs, threaded screws, or any other suitable fastening means known in the art. An internal flange 32 supports vertical separators 22 within non-expandable portion 19 of middle section 18 . FIG. 4 b depicts the separators 22 as being curved, and permits flange 32 to have a smaller lip, thus increasing the size of the cavity through which liquid may flow. Although the embodiment depicted in FIGS. 4 a and 4 b shows four separators, the choice of configuration of separators 22 as rectangular or of some other shape, and of the number of separators, is not critical to the function of the invention and may be a matter of design choice.
FIG. 5 is a plan view of the tapered section 24 . Threaded through hole 28 receives the threaded bolt 26 , while the smaller upper diameter 34 and larger lower diameter 36 form a frusto-conical surface that will cause expandable panels 20 to be forced outwardly when the tapered section 24 is drawn upward as bolt 26 is tightened.
In use, the locking floor sink drain screen 10 is inserted into the mouth of a floor sink drain so that the grate 12 rests on the surface of the area being drained and, preferably, within an indented cavity that will support the grate flush with the surface to be drained. The middle portion 18 and tapered portion 24 of the device are attached to the grate with threaded bolt 26 , and extend downwardly to fit within the upper end of a drain pipe. The bolt 26 is then tightened which serves to draw the tapered section 24 toward the middle section 18 , which causes the expandable panels 20 to expand laterally to wedge against and frictionally engage the drain pipe opening. This ensures that the device 10 will not be displaced during use. Because the device of this invention is intended for use in drains where the drain pipe is smaller than the mouth of the floor sink drain, liquid can flow through openings 16 in the grate 12 and through spaces between vertical separators 22 , and further through the large opening in tapered section 24 , where it will be channeled into the drain pipe. However, any large objects will be blocked by the mesh-like structure of the grate 12 . If the openings 16 become clogged over time, bolt 26 can be loosened, allowing tapered section 24 to be forced downward, releasing friction on expandable panels 20 and allowing the floor sink drain 10 to be removed for cleaning. Subsequently, the drain screen lock 10 can be reinserted in the floor sink drain opening in the manner described above for further use.
Bolt 26 may be tamperproof such that special tools are required for installation or removal of the device from a drain. Because the drain pipe will be some distance below the grate and floor openings, the middle section 18 and tapered section 24 may be of any length, and will be sized to fit within a drain of corresponding size. Vertical separators may be of any height but, preferably, will be no longer than about one inch (2.54 cm).
Numerous variations and modifications can be made without departing from the spirit of the present invention. Therefore, it should be clearly understood that the forms of the present invention described above and shown in the accompanying drawing are illustrative only and are not intended to limit the scope of the present invention. | An improved locking floor sink drain screen for an enlarged drain is provided. The locking floor sink drain positively precludes passage of large objects, while permitting free passage of fluid and which can quickly and easily be removed for cleaning. Vertical separators provide spaces through which water can flow from the enlarged drain opening into a standard drain pipe. In some embodiments, a special, tamperproof locking key may be used to prevent unauthorized disassembly of the installed floor drain screen. | 4 |
BRIEF DESCRIPTION OF THE INVENTION
Field of the Invention
This invention relates to the measuring of muscle strength.
BACKGROUND OF THE INVENTION
There has long been a need for devices to accurately measure muscle strength and to provide data regarding changes in muscle strength of subjects on which such apparatus is used. Physical therapists, athletic trainers and orthopedic surgeons, for example, need such apparatus to accurately moniter a patient's history and to systematically test for muscle improvements.
Muscle testing is an integral and important part of a complete physical exam since it provides information not otherwise obtained that is useful in differential diagnosis, prognosis and treatment of neuromuscular and musculoskeletal disorders. A knowledge of the relative strengths of the various muscles of the body provides a foundation for rehabilitation and strengthening of the muscles in a programmed manner that will give maximum overall fitness. Knowledge of the strengths of muscles before and after administration of certain drugs such as cholinergic drugs may also assist in determining the type and nature of medications and other treatments subsequently used to treat progressive muscular weaknesses such as myasthenia gravis.
PRIOR ART
A number of devices have been proposed in the past to provide for muscle testing and for measuring various characteristics of muscles. Some of these known devices are shown, for example, in U.S. Pat. Nos. 3,482,564, issued to Robinson; 3,680,386, issued to Cannon; 3,690,208, issued to Daniels; 3,752,144, issued to Weigle, Jr.; 3,916,876, issued to Freeman; and 4,337,780, issued to Metrick. The aforesaid devices utilize a variety of transducers to transmit muscular pressure application to different kinds of readout and recording devices. These devices, in general, strive to obtain accurate input, accurate repeat readings during subsequent test periods, and a temporary or permanent record display indicative of the results obtained. Several of the devices use transducers incorporating fluid filled bags or cylinders and others use spring-loaded pressure sensors.
Several of the patents identified above disclose the use of frameworks for positioning a test subject such that exact duplication of test conditions will be obtained during subsequent tests. The apparatus of others of the patents use harnesses or other structures in an attempt to position the apparatus on a test subject so that identical test conditions are established for a plurality of tests.
A muscle testing system incorporating a manually held pressure input transducer connected by a cable and a microprocessor to a digital readout display has been advertised under the trademark "MYO-METRIC II" by Mycron Medical, Inc., Fayettville, Ark. The MYO-METRIC II unit uses a twin element bridge type of pressure transducer, with an air bag configuration, and requires consistent placement against a subject user's body if the muscles of the body are to be monitered on a continuing basis.
To the best of my knowledge there has not heretofore been available a testing system having a force sensor or transducer that will accurately measure minute pressure changes; that will perform accurately even if force application inputs are applied at different angles, to thereby give accurate repeat measurements during subsequent test periods, even if certain exact test conditions are not duplicated; and to provide both an immediately observable readout showing test results, comparison of present with past test results, and permanent copies of such readout for use by the subject being tested, the persons conducting the tests, and others.
Principal objects of the present invention are to provide a muscle strength measuring device having a force input transducer that will provide accurate measurements of muscle strength, even when used for repeat tests, without the necessity for accurate positioning of the transducer on a point relative to a body part containing a muscle being tested.
Other objects are to provide a force input transducer that is coupled to a computer programmed to provide both immediate screen display and permanent display of the muscle strength detected by the transducer; display of comparative test results from a plurality of tests; display of test results as compared with desired conditions; and other date useful to the subject being tested and to others.
FEATURES OF THE INVENTION
Principal features of the present invention include a force input transducer having a hand-held transducer housing with a support shaft rigidly attached to and projecting from a cantilevered support arm located within the transducer housing. A cushion is provided on one face of the transducer housing as a support surface for a tester and a strap at the opposite face for securing the housing to the hand of a tester.
The support shaft is threaded to receive correspondingly interiorly threaded pressure plates shaped to conform to selected body portions of the subject being tested.
A plurality of strain gauges are mounted to the support shaft and the cantilevered support arm in a pattern such that force application to an attached pressure plate, regardless of the direction of such force application, will be accurately measured as indicative of muscle strength.
The strain gauges are connected through a digital information processor circuit to a computer programmed to display readings obtained, a comparison of current and past readings, and a comparison of past and current readings against desired results and to provide hard copy history and text results for use by subjects being tested, therapists, doctors or others having an interest in such test results.
Other objects and features of the invention will become apparent from the following detailed description and drawings disclosing what is presently contemplated as being the best mode of the invention.
THE DRAWINGS
In the drawings:
FIG. 1 is a somewhat schematic elevation view of the transducer apparatus of the invention;
FIG. 2, an axial vertical section through the pressure input transducer device of the invention;
FIG. 3, a perspective view of an alternate pressure plate of the invention;
FIG. 4, a view like that of FIG. 3, but showing another embodiment of pressure plate;
FIG. 5, a view like that of FIG. 3, but showing still another embodiment of pressure plate;
FIG. 6, a schematic diagram of a typical circuit used with the device of the invention;
FIG. 7, a schematic front elevational view of an isolated transducer arrangement of the invention;
FIG. 8, a side elevational view of the transducer arrangement of FIG. 7;
FIG. 9, a top plan view of the transducer arrangement of FIG. 7 showing placement of the strain gauges;
FIG. 10, a representation of an isolated post to which a pressure plate is attached and the x-y designations for stress, strain, and moment measurements;
FIG. 11, a representation of an isolated cantilever bar to which a post is attached and the x-y designation for stress, strain, and moment measurements;
FIG. 12, the isolated cantilever bar of FIG. 11 showing preferred dimensions;
FIG. 13, the isolated post of FIG. 10 indicating a preferred diametrical dimension; and
FIG. 14, a top plan view of the transducer arrangement of FIG. 7 showing examples of various possible moment lever arms for calculation purposes.
DETAILED DESCRIPTION
Referring now to the drawings:
In the illustrated preferred embodiment, the apparatus of the invention, shown generally at 10, includes a pressure input transducer device 11, a computer 12 having a display screen 13, and a printer 14.
The input transducer device 11 includes a transducer housing 15 having a rigid plate forming a base 16 therefor. A cap 17 having a cushioned pad 18 thereon is fixed to the exterior face of the base 16 and a resilient strap 20 extends over the cushioned pad 18.
A substantially rigid support arm assembly 21 has an integral leg 22 affixed to the base 16 and a support arm cantilevered from the leg 22, above the base 16.
A substantially rigid support post 23 is affixed to and extends exteriorly of housing 15, and from the arm 21 and is threaded at 24 on its free, exterior end to receive a pressure plate 25.
A strain gauge 26 is bonded to one side of the support post 23 and a second strain gauge 27 is bonded to the support post ninety degrees (90°) turned from the first strain gauge 26. A third strain gauge 28 is bonded on the centerline of the support arm 21 and in the central plane of gauge 27. The usual electrical lead wires 29 and 30 are respectively attached to opposite ends of each of the strain gauges and then extend out of housing 15 at 31 to be connected to the computer 12, through digital information processor circuit 12a.
The pressure plate 25 comprises a rigid disk 32 from which a centrally positioned, interiorly threaded boss 33 extends. A contact layer 34 of plastic or other suitably textured and easily cleaned material covers the face of plate 25 opposite boss 33 to serve as a contact surface against the skin of a subject user of the device.
The disk-shaped pressure plate 25 is suitable for application to many body parts for muscle testing, but pressure plates having other shaped surfaces for even better application to some body parts may be used in place of the pressure plate 25. The pressure plates 35, 36 and 37, shown respectively in FIGS. 3, 4 and 5, each include an elongate, curved, substantially rigid disk 38 and a contact layer 39 on the inner curve thereof. An interiorly threaded boss 40 extends from the outer curve side of the disk 38 to allow the pressure plates to be attached to post 23 in place of plate 25. Each of the plates 35, 36 and 37 has a different degree of curvature than does the other plates so that each plate is better adapted to contact with various body portions.
The resilient strap 20 has its ends inserted through slots 39 in the base plate and folded back and sewn to prevent pullout of the strap from the housing.
The strain gauges 26, 27 and 28 are preferably monolithic silicon gauges each having a longitudinal axis. The longitudinal axes of gauges 26 and 27 are aligned with the central longitudinal axis through the support post 23 and the longitudinal axis of support arm 21. The strain gauges 26, 27 and 28 are connected by pairs of lead wires 29 and 30 and a separate electric circuit to signal condition circuits 40, 41 and 42, respectively FIG. 6 and, to a multiplexer and counter circuit 45 of the digital information processor circuit 12a.
The multiplexer and counter circuit 45 is connected through an A to D convertor 46 to a processor 47, and the processor is coupled by an interface driver 48 to a computer.
With the axes of the strain gauges arranged in the manner described above, any force application to the pressure plate being used will provide a correct load reading regardless of the location or angle of force applied to the pressure plate.
Mathematical verification of the accuracy of the readout of the testing device of the invention is shown below, with reference to FIGS. 7-14.
FIGS. 7-9 indicate positioning of the strain gauges used.
Analysis of Random Leadin of Pressure Plate vs. Force Application Readout, See FIGS. 7-9 ##EQU1##
AT SECTION 1-1, See FIGS. 7 and 10
STRESS xx=Stress on the post due to a vertical load causing rotation about the X axis
STRESS yy=Stress on the post due to a vertical load causing rotation about the Y axis.
Mxx=Moment about the X axis.
Myy=Moment about the Y axis.
P=Vertical force applied to the pressure plate
STRAINxx=Strain on the post due to a vertical load causing rotation about the X axis. Measured by gage 28.
STRAINyy=Strain on the post due to a vertical load causing rotation about the Y axis. Measured by gage 27. ##EQU2##
E=Modulus of elasticity=30,000,000 psi
A 1-1 =Area of post
AT SECTION 2-2, See FIG. 11
STRESS 2-2 =Stress on cantilever bar due to a vertical load causing rotation about the X axis.
STRAIN 2-2 =Strain on cantilever arm due to a vertical load causing rotation about the X axis. ##EQU3##
l 2 =Distance between the center of the post and where the cantilever arm hooks onto its support.
Mxx=Myy at section 1-1, Myy at section 1-1 is applied to the end of the cantilever arm.
Using stress and strain equations, a relationship between the three strain gages can be set up to calculate the force P applied to the pressure plate.
AT SECTION 1-1 ##EQU4##
AT SECTION 2-2 ##EQU5##
STRAINyy, STRAINxx and STRAIN 2-2 are known from the strain gages S 2-2 , A 1-1 and S 1-1 are constants that can be calculated. This leaves P, Mxx and Myy as unknowns. E is a constant that is looked up in a table. Using matrix algebra, the three unknowns can be solved for with the three equations above. ##EQU6##
EQUATIONS OF FET SYSTEM
Properties ##EQU7##
EQUATIONS
16.125 (P)+0+459.137(Myy)=30(10).sup.6 (STRAINyy)
16.125 (P)+459.137(Mxx)+0=30(10).sup.6 (STRAINxx)
400 (P)+0+400.0(Mxx)=30(10).sup.6 (STRAIN.sub.2-2)
EXAMPLE OF CALCULATIONS, SEE FIG. 14
Directions
Moment lever arms are measured on an XY coordinate system. An example is point B. Its lever arm is -1" in the X direction and +1" in the Y direction.
EXAMPLE
Put A0.5# load at point A
Myy=0.5# (-1")=-0.5#-IN
Mxx=0 At Section 1-1 ##EQU8##
__________________________________________________________________________PositionCalculated EquationsSee Pg 5Load Myy Mxx STRESS yy STRESS xx STRESS.sub.2-2 Load Myy Mxx__________________________________________________________________________A .5 -.5 0 -221.506 8.062 -400 .5 -.5 0B .5 -.5 .5 -221.506 237.630 -400 .5 -.5 .5C .5 0 .5 +8.062 237.630 -200 .5 0 .5D .5 .5 .5 +237.630 237.630 0 .5 .5 .5E .5 .5 0 +237.630 +8.062 0 .5 .5 0F .5 .5 -.5 +237.630 -221.506 0 .5 .5 -.5G .5 0 -.5 +8.062 -221.506 -200 .5 0 -.5H .5 -.5 -.5 -221.506 -221.506 -400 .5 -.5 -.5__________________________________________________________________________
Using the calculated stresses in three simultaneous equations gives the same load used to calculate the stresses. Therefore the equations are correct.
Although a preferred form of my invention has been herein disclosed, it is to be understood that the present disclosure is by way of example and that variations are possible without departing from the subject matter coming within the scope of the following claims, which subject matter I regard as my invention. | Apparatus for use in testing muscle strength comprising a transducer including strain gauges mounted to provide deflection readings that will be accurate for even different directions of force application and read out apparatus receiving strain gauge data and for displaying output data indicative of muscle strength. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a new method of producing 1-(4'-isobutylphenyl)ethanol (IBPE).
2. Background Information
The compound 2-(4'-isobutylphenyl)propionic acid, more commonly known as ibuprofen, is a well-known nonsteroidal anti-inflammatory drug which has been converted from ethical, i.e., prescription, to over-the-counter status.
A recently proposed method of producing ibuprofen is disclosed in pending U.S. patent application Ser. No. 028,514, filed Mar. 20, 1988, by Elango et al, involves the carbonylation of IBPE under prescribed conditions using any of certain palladium-containing catalysts. Also disclosed in this application is the preparation of IBPE by the hydrogenation of 4-isobutylacetophenone (IBAP) using any of various hydrogenation catalysts, including Raney nickel.
Activated sponge nickel, e.g., Raney nickel, which is a widely used type of hydrogenation catalyst, is pyrophoric, i.e., it tends to ignite spontaneously in the presence of air. Because of this, it is stored and shipped submerged in a liquid which effectively protects it from contact with air. The most common type of protective liquid used for this purpose is composed preponderantly of water, e.g., water containing a small amount of dissolved alkaline material, e.g., sodium hydroxide.
3. Description of Related Art
The following information is disclosed in accordance with the terms of 37 CFR 1.56, 1.97 and 1.98.
Japanese Kokai Patent No. SHO 55 [1980]-27147, published Feb. 27, 1980, and assigned to Mitsubishi Petrochemical Co., discloses the formation of aryl-substituted carboxylic acids, e.g., ibuprofen, by reacting an aryl-substituted alcohol, e.g., IBPE, with carbon monoxide and water in the presence of a hydrogen fluoride catalyst. Also disclosed generally is the synthesis of the aryl-substituted alcohol by reducing the corresponding ketone.
Czech Patent No. CS 219,752 of Sept. 15, 1985, discloses a process of making ibuprofen from isobutylbenzene including the step of reducing IBAP to IBPE using lithium aluminum hydride as reductant.
D. P. Curran, J. Am. Chem. Soc. 1983, 105, 5826-5833, discloses the reduction of isoxazolines to beta-hydroxy ketones using Raney nickel as catalyst and aqueous methanol as solvent. The washing of Raney nickel free of hydroxide with 20-30 water washes prior to use is shown on page 5830.
M. Delepine et al, Bull. Soc. Chim. France, 1937, 31-49, teach the preparation of aromatic carbinols such as methylphenylcarbinol and ethylphenylcarbinol by hydrogenation of the corresponding ketone using Raney nickel promoted with alkali as catalyst, and ethyl alcohol as solvent.
M. Freifelder et al, J. Pharm. Sci. 53, 967 (1964), teach the preparation of 1-phenylethanol by hydrogenation of acetophenone using Raney nickel promoted with alkali as catalyst and ethyl alcohol as solvent.
M. Freifelder, Catalytic Hydrogenation in Organic Synthesis--Procedures and Commentary, John Wiley, New York (1978), pages 81-89, discloses the use of Raney nickel as catalyst for the hydrogenation of various aromatic aldehydes and ketones to the corresponding alcohols, e.g., acetophenone to 1-phenyl-1-ethanol in ethyl alcohol as solvent. On page 83, the reference states that Raney nickel "may well be the one of choice for the reduction of aromatic aldehydes and ketones . . . "
L. Kotlyarevskii et al, Khim. prom., 1981 (7), 391-393, translated in Soviet Chemical Industry, 13:7, 813-819 (1981), disclose a process of synthesizing p-divinylbenzene, including the step of reducing p-diacetylbenzene (p-DAB) using Raney nickel as catalyst, to produce "1-4-bis(α-oxyethyl)benzene."
D. Nightingale et al, J. Org. Chem. 14, 1089-1093 (1949), teach at page 1090 the hydrogenation of various aromatic ketones using Raney nickel as catalyst to produce the corresponding carbinol and aromatic hydrocarbon.
G. G. Hawley, Condensed Chemical Dictionary, 10th Ed., Van Nostrand Reinhold, New York (1959), page 883, and M. Windholz, Ed., The Merck Index, 10th Ed., Merck & Co., Rahway, NJ (1983), p. 8019, show that Raney nickel is pyrophoric and is generally stored under a protective liquid such as water.
SUMMARY OF THE INVENTION
In accordance with this invention, 1-(4,'-isobutylphenyl)ethanol (IBPE) is produced by hydrogenating 4-isobutylacetophenone (IBAP) with hydrogen in the absence of a solvent using as a catalyst a treated activated sponge nickel catalyst, e.g., Raney nickel, obtained by subjecting such a catalyst wetted with a protective liquid composed preponderantly of water to a washing treatment with an organic washing liquid in which the aqueous protective liquid is substantially soluble, such washing liquid being substantially soluble in IBAP or IBPE. Such a washing treatment has the effect of substantially increasing the conversion of IBAP and yield of IBPE within a practical reaction time. After the treatment of the catalyst with organic washing liquid, it may be optionally washed with IBAP or IBPE which, in most cases, has the effect of reducing the contamination of the IBPE product with organic washing liquid. Note that, in accordance with any of the foregoing treatments, the catalyst is not permitted to become exposed to the air in the absence of any protective liquid at all. Thus, while the catalyst is initially wetted with a protective liquid composed preponderantly of water, it is finally utilized in the process wetted with organic washing liquid, IBAP or IBPE, each of which is effective in preventing the catalyst from igniting on contact with air.
DESCRIPTION OF PREFERRED EMBODIMENTS
Activated sponge nickel catalysts, e.g., Raney nickel, are a well-known class of materials effective for various hydrogenation reactions. They are prepared by treating an alloy of approximately equal amounts by weight of nickel and aluminum with an aqueous alkali solution, e.g., containing about 25 wt. % of sodium hydroxide. The aluminum is selectively dissolved by the aqueous alkali solution leaving particles having a sponge construction and composed predominantly of nickel with a minor amount of aluminum. Promotor metals such as molybdenum or chromium may be also included in the initial alloy in an amount such that about 1-2 wt. % remains in the sponge nickel catalyst. These catalysts also contain surface hydrogen which causes them to ignite if exposed to air without being coated with a protective liquid, e.g., composed preponderantly of water, as contemplated for treatment under this invention. Protective liquids of the latter type most commonly used are aqueous alkaline solutions, e.g., of sodium hydroxide, having a pH of about 9.5-10.5, in view of its relative cheapness and safety.
Organic washing liquids useful in the method of this invention in which the protective liquid on the catalyst is substantially soluble, and which are substantially soluble in IBAP or IBPE, are, for example, lower alkanols containing one to three carbon atoms, e.g., methanol, ethanol, or isopropanol, cyclic ethers such as tetrahydrofuran, dioxane-1,4, dioxane-1,3, and diethers and monoethers of ethylene glycol and diethylene glycol such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, ethylene glycol monomethyl ether and ethylene glycol monoethyl ether.
The term "substantially soluble" in the foregoing discussion means, for example, capable of dissolving in the stated solvent in an amount of at least about 50 wt. % based on the weight of the solution in the stated solvent. Preferably, the washing liquid is completely miscible with the protective liquid and IBAP or IBPE.
The washes with the organic washing agent and, if utilized, IBAP or IBPE, are accomplished, for example, by stirring or agitating the nickel catalyst with an amount of the washing liquid sufficient to wet all of the nickel particles, e.g., for a period of about 1 to 5 minutes in the case of 500 g of catalyst, and decanting the excess washing liquid. While this may be done once for each washing liquid, it is preferably done at least 2 or 3 times. In most cases, the washes may be carried out at room temperature, although elevated temperatures may be utilized to obtain the desired solubilities.
The hydrogenation of IBAP to form IBPE is accomplished by contacting IBAP and hydrogen in the absence of a solvent with an activated sponge nickel catalyst treated as described previously. The catalyst may be used in an amount, for example, of about 1% to 30 wt. %, preferably about 3 to 20 wt. %, based on the weight of the total reaction mass. In carrying out the reaction, the hydrogen pressure may be in the range, for example, of about 10 to 1200 psig, preferably about 200 to 1000 psig; the reaction temperature may be in the range, for example, of about 10° to 150° C., preferably about 40° to 80° C.; and the reaction time may be in the range, for example, of about 0.25 to 10.0 hours, preferably about 1.0 to 4.0 hours.
The following examples further illustrate the invention.
EXAMPLES 1 to 13
In these examples, a weighed amount of an activated sponge nickel catalyst composed of particles having an average dimension of about 25 to 45 microns and slurried in alkaline water having a pH of about 9.5-10.5 in which it was stored, was transferred to a mixing vessel, using a small amount of deionized water to aid in the transfer. An approximately equal volume of isopropanol or ethanol was added to the vessel and the contents were mixed using an overhead mixer. The catalyst was allowed to settle and the alcohol/water layer decanted using a magnet to aid in the decanting. The alcohol wash was repeated in a similar fashion two more times. In some examples, the catalyst was then similarly washed three times in either the reactant IBAP or the product IBPE.
The catalyst slurried in the last batch of wash liquid was then charged to a stirred autoclave and a weighed amount of IBAP was also charged. The autoclave was sealed, purged of air with nitrogen, and pressure checked, and hydrogen was introduced. Stirring was begun, the autoclave was heated to maintain a desired reaction temperature, and hydrogen was fed on demand to maintain a desired reaction pressure. When hydrogen uptake had ceased marking the end of the reaction, the autoclave was cooled 10°-15° C., the hydrogen vented, and the autoclave purged with nitrogen. The IBPE product was filtered from the catalyst and analyzed by gas chromatography.
The catalyst used in the examples were all activated sponge nickel catalysts as described previously and were considered equivalent for the purpose of carrying out the method of this invention, although obtained from different sources as follows: Raney Active Metal Catalysts R3100 (Examples 1 to 7), R3200 (Example 12) and R2400 (Example 13), all obtained from Davison Chemical Division of W. R. Grace & Co., Activated Nickel Catalyst BK111W (Example 8) and BK113W (Examples 9 and 10) obtained from Degussa Corp., and Sponge Metal Catalyst A7l00 (Example 11) obtained from Activated Metals & Chemicals, Inc. All the catalysts contained about 1% of molybdenum as a promotor except R2400 (Example 13) which contained 1-2% chromium.
The conditions and results are shown in the table which indicates the mode of washing of the catalyst (Cat. Wash.), i.e., isopropanol only (IPA), ethanol only (EtOH), isopropanol and IBAP (IPA/IBAP) or isopropanol and IBPE (IPA/IBPE), the amount of catalyst utilized as a percent of the total dry weight of the reaction mass, i.e., calculated on a dry basis (Cat. Amt.), the reaction pressure (Press.), the reaction temperature (T), the reaction time (t), the percent conversion of IBAP (conv.) and analyses of the product in terms of weight percents of IBAP, IBPE, isopropanol (IPA) and water (H 2 O). The catalyst of Example 1 was used in Example 2 without any further washing, and the weight percent of IBPE in all products includes both 1-(4'-isobutylphenyl)ethanol and 1-(3'-isobutylphenyl)ethanol, although the latter isomer was never more than about 3% of the total of the two isomers.
TABLE__________________________________________________________________________ Cat. Amt. Press. T t Conv. Product Analysis, wt %Ex. Cat. Wash wt % psig °C. min. % IBAP IBPE IPA H.sub.2 O__________________________________________________________________________1 IPA/IBAP 10.2 250 60 97 99.9 0.14 96.9 0.11 0.342 IPA/IBAP 10.2 250 60 103 99.7 0.03 96.1 0.00 0.173 IPA 10.0 250 60 77 99.7 0.26 95.8 2.66 0.524 IPA/IBPE 7.5 250 60 90 99.8 0.22 97.6 1.30 0.595 IPA 10.1 500 75 75 99.4 0.56 91.8 2.70 0.396 IPA 5.8 500 75 170 99.5 0.45 94.2 1.58 0.447 IPA 10.5 1000 55 95 99.5 0.52 90.9 2.80 0.698 IPA 10.4 250 60 222 99.8 0.16 82.9 5.56 0.989 IPA/IBAP 10.4 250 60 203 99.7 0.28 88.7 0.11 0.7310 IPA/IBPE 7.5 250 60 145 99.4 0.55 86.5 1.90 1.3011 IPA/IBPE 7.6 250 60 148 98.7 1.26 80.8 0.92 1.6412 IPA 10.5 250 60 198 99.7 0.29 90.0 5.44 0.7813 EtOH 10.0 350 65 145 91.5 8.40 85.7 -- --__________________________________________________________________________
COMPARATIVE EXAMPLE
The conditions of Example 1 were followed except that the catalyst wet with alkaline water as a protective liquid was not washed with isopropanol or IBAP and the amount of catalyst in the reaction mass was 10.1 rather than 10.2 wt. %. Moreover, in attempting to increase the conversion of IBAP, a reaction temperature of 75°-85° C. was utilized and the reaction was continued for 240 min, longer than in any of Examples 1 to 13. Nevertheless, the IBAP conversion was only 13.7% and the product contained 84.1 wt. % of IBAP, 9.1 wt. % of IBPE and 0.73 wt. % of H 2 O.
The results of Examples 1 to 13 as shown in the Table and of the comparative example indicate that high conversions of IBAP and products containing high percentages of desired IBPE are obtained utilizing the washing procedure of this invention. Moreover, when an IBAP or IBPE wash is carried out after the wash with organic washing liquid, e.g., isopropanol, the product in most cases is less contaminated with organic washing liquid than when no IBAP or IBPE wash is included.
When an activated sponge nickel catalyst stored in alkaline water was used for the hydrogenation of IBAP to IBPE without the washing treatment of this inventory, the conversion of IBAP and yield of IBPE fell drastically, as shown by the results of the foregoing Comparative Example. | A method is provided for the production of 1-(4'-isobutylphenyl)ethanol (IBPE) comprising hydrogenating 4-isobutylacetophenone (IBAP) in the absence of a solvent using as a catalyst a treated activated sponge nickel catalyst, e.g., Raney nickel, obtained by subjecting such a catalyst wetted with a protective liquid composed preponderantly of water to a washing treatment with an organic washing liquid in which the aqueous protective liquid is substantially soluble and which is substantially soluble in IBAP or IBPE, e.g., a lower alkanol such as methanol, ethanol or isopropanol. The catalyst optionally may also be washed with IBAP or IBPE after the wash with the organic washing liquid and before being used in the hydrogenation reaction. The washing treatment results in substantially higher conversions IBAP and increased yields of IBPE with a practical reaction time. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to gasoline fuels. In particular, the present invention concerns gasoline fuels free from or having only a low content of water-soluble ethers. The present invention also relates to a method of reducing the emissions of one or more pollutants, selected from the group consisting of CO, NO x , particulates and hydrocarbons, from an automotive engine.
[0003] 2. Description of Related Art
[0004] Currently large amounts of water-soluble ethers (e.g. MTBE, methyl tert-butyl ether) are used by petroleum refiners as gasoline components for formulating gasoline products, which, upon combustion in automotive engines, will give rise to low exhaust emissions of harmful pollutants, such as carbon monoxide and nitrogen oxides. To mention an example, present-day Californian grade gasoline, abbreviated CARB II (California Phase II gasoline), contains about 12 vol.-% MTBE and it essentially meets the specifications set by the California Air Resources Board. It has an oxygen content of about 2%. However, MTBE is water-soluble and biologically very stable, and it may have a tendency to accumulate in groundwater. Thus, the use of water-soluble ethers, such as MTBE, as a component of gasoline fuels will have to be avoided in the future in California and alternative solutions should be found to provide clean-burning high-performance fuels for automotive engines.
SUMMARY OF THE INVENTION
[0005] It is an aim of the present invention to eliminate the disadvantages of the prior art and to provide a novel gasoline fuel, which is essentially free from water-soluble ethers while still meeting stringent exhaust emission limits.
[0006] It is another object of the invention to provide a method of reducing the emissions of an automotive engine of one or more pollutants selected from the group consisting of CO, NOx, particulates and hydrocarbons compared to combusting a CARB II fuel.
[0007] These and other objects of the invention and benefits associated therewith will become evident from the following detailed description of the invention.
[0008] The present invention is based on the finding that when gasoline fuels without a significant amount of water soluble ethers are produced by blending several hydrocarbon-containing streams together so as to formulate a gasoline product suitable for combustion in a gasoline spark-ignition internal combustion engine, reductions in the emissions of one or more pollutants selected from the group consisting of CO, NOx, particulates and hydrocarbons upon combustion of the gasoline product in such an engine system can be attained by controlling certain chemical and/or physical properties of said gasoline product.
[0009] It is well known that olefins, primarily light olefins and in particular tertiary olefins, contribute to the formation of ozone in the atmosphere. However, the relative ozone formation potential of heavy olefins, with a boiling point greater than about 90° C. (194° F.), is very low.
[0010] We have found that heavier olefins have a positive effect on the tail pipe emissions and, therefore, it is advantageous to control and minimize the amount of light olefins only in automotive gasoline.
[0011] According to the present invention, the content of light olefins, having a boiling point below +90° C. (194° F.), in particular below 85° C. (185° F.), should be less than about 10 vol.-%, preferably less than 6 vol.-% of the gasoline composition. These olefins are made up by C 2 -C 6 hydrocarbons. By contrast, the content of heavy olefins having a boiling point above +90° C., preferably above +95° C. (203° F.), can be more than 1 vol.-%, preferably 2 vol.-% or more, up to about 30 vol.-%. Suitable heavy olefins contain 8 carbon atoms or more and they are preferably branched. Particularly preferred examples include branched isoolefins containing 8 to 12 carbon atoms, such as trimethylpentenes (isooctenes), trimethylhexenes and trimethylheptenes.
[0012] In the fuel, the heavy olefins can used together with paraffines, in particular isoparaffines, such as isooctane, and with alcohols, such as ethanol or methanol.
[0013] Thus generally, the invention provides a gasoline fuel composition, having in combination
[0014] an octane value (R+M)/2 of at least 85;
[0015] an aromatics content less than 25 vol. %; and
[0016] a water-soluble ethers content of less than 1 vol. %.
[0017] The composition has a content of olefins, at least 10% of which is formed by heavy olefins having a boiling point above +90° C. In particular, the composition contains up to 40% olefins, and it contains less than 6 vol.-% of light olefins having a boiling point below +90° C., and at least 1 vol.-% heavy branched olefins having a boiling point above +90° C.”
[0018] According to an exemplifying embodiment, the present invention concerns an unleaded, clean-burning gasoline fuel with a low content of water-soluble ethers, suitable for combustion in a spark-ignition internal combustion engine and especially in a gasoline direct injection, lean-burning automotive engine having the following properties:
[0019] an octane value (R+M)/2 of at least 85;
[0020] an aromatics content less than 25 vol-%;
[0021] a water-soluble ethers content less than 1 vol-%;
[0022] a 10% D-86 distillation point no greater than +150° F. (65.6° C.);
[0023] a 50% D-86 distillation point no greater than +230° F. (110° C.);
[0024] a 90% D-86 distillation point no greater than +375° F. (190.6° C.);
[0025] Reid Vapor Pressure of less than 9.0 psi (62 kPa);
[0026] a light olefins content, with boiling point below +90° C., less than 6 vol-%; and
[0027] a combined content of trimethylpentenes, trimethylhexenes and trimethylheptenes greater than 1 vol. %.
[0028] Reductions in emissions of one or more pollutants selected from the group consisting of CO, NO x , particulates and hydrocarbons compared to combusting a CARB II fuel can be obtained by
[0029] a) introducing into said automotive engine an unleaded gasoline having a composition according to any of the above defined gasolines:
[0030] b) combusting the unleaded gasoline in said engine;
[0031] c) introducing at least some of the resultant engine exhaust emissions into the catalytic converter; and
[0032] d) discharging emissions from the catalytic converter to the atmosphere.
[0033] Considerable advantages are obtained by the present invention. As will appear from the results presented below, MTBE and similar water-soluble alkyl ethers can be replaced by an increased content of heavier olefins, in particular isoolefins, such as isooctene, in CARB gasoline, without any backsliding of exhaust gas quality. On the contrary, compared to an MTBE-containing fuel, when combusted in a spark ignition internal combustion engine, and particularly in a gasoline direct-injection, lean-burning automotive engine, the present fuels will produce a relatively low amount of gaseous pollutants, in particular one or more of NO x CO, particulates and unburned or incompletely burned hydrocarbons. Further, there would appear to be a reduction of fuel consumption.
[0034] Based on a study commissioned by the EU, there will be no ban on water-soluble alkyl ethers in gasoline in Europe in the foreseeable future, at least within the next 10 or 20 years. It should be pointed out that the present gasoline composition can also be easily converted for use with alkyl ethers by including a desired amount of an alkyl ether as an oxygenate component instead of an alcohol or in addition to that alcohol. In such gasolines, the total concentration of ether+alcohol can be up to 8 vol. % giving rise to an oxygen concentration of 1 to 3 vol. % Next, the invention will be examined more closely with the aid of the following detailed description with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] [0035]FIG. 1 shows in the form of a bar chart the total hydrocarbon emissions of six different test cars for six different gasoline compositions;
[0036] [0036]FIG. 2 shows the corresponding bar chart of carbon monoxide emissions;
[0037] [0037]FIG. 3 shows the corresponding bar chart of nitrogen oxide (NOx) emissions;
[0038] [0038]FIG. 4 shows the corresponding bar chart of carbon dioxide emissions;
[0039] [0039]FIG. 5 shows the corresponding bar chart of combined HC and NOx emissions;
[0040] [0040]FIG. 6 shows the corresponding bar chart of particulate matter emissions; and
[0041] [0041]FIG. 7 shows the corresponding bar chart of gasoline consumption.
[0042] [0042]FIG. 8 shows in the form of bar chart the change (%) of the content of methane in exhaust gases compared to fuel RFG for two (E and F) cars of the set of test cars.
[0043] [0043]FIG. 9 shows the corresponding bar chart of 1,3-butadiene content of exhaust gases.
[0044] [0044]FIG. 10 shows the corresponding bar chart of benzene content of exhaust gases.
[0045] [0045]FIG. 11 shows the corresponding bar chart of BTEX compaunds content of exhaust gases.
[0046] [0046]FIG. 12 shows the corresponding bar chart of formaldehyde content of exhaust gases.
[0047] [0047]FIG. 13 shows the corresponding bar chart of acetaldehyde content of exhaust gases.
[0048] [0048]FIG. 14 shows content of polyaromatichydrocarbons (PAH14; EPA PAH) of the particulate matter of the exhaust gases from the two test cars (E and F).
[0049] [0049]FIG. 15 shows the amount of the semivolatile part of particulate matter above.
[0050] [0050]FIG. 16 shows the effect of particulate matter above on the AMES-mutagenicity (rev/mg).
[0051] [0051]FIG. 17 shows the effect of particulate matter above on the AMES-mutagenicity (krev/km).
DETAILED DESCRIPTION OF THE INVENTION
[0052] The present invention relates to a low-emission, gasoline fuel composition, which is essentially free from water-soluble ethers typically used for increasing the octane number of the fuel and for improving the combustion properties thereof. The properties referred to above and in the following are determined by standard test methods outlined in Table 3. Thus, for example, distillation cuts are determined by ISO 3405 (corresponds to ASTM D86), and vapour pressure by EN 13016
[0053] The ether content of the present fuel compositions is 1 vol.-% or less, preferably less than 0.6 vol.-%, in particular less than about 0.4 vol.-%. Thus, the gasoline composition is “essentially free from water-soluble ethers”.
[0054] Typically, the fuel has an octane value (R+M)/2 of at least 85, preferably at least 92, in particular at least 95.
[0055] The aromatics content is less than 25 vol. %. It has a total olefins content of more than about 7 vol.-%, typically less than about 40 vol.-%. A considerable part of the olefins are heavy olefins, such as C 7 +olefins. When the total amount is about 7 vol. %, at least about 15% of the olefins are heavy, and when the total content is 20 to 30 vol.-%, the heavy olefins make up about 70 vol.-% or more.
[0056] It is preferred to limit the total concentration of olefins to about 20 vol.-%.
[0057] The preferred heavy olefins are isoolefins comprising 8 to 14 carbon atoms. In particular, the heavy olefins are selected from the group of branched octenes, nonenes and decenes. The following examples can be mentioned: trimethylpentenes, trimethylhexenes and trimethylheptenes. The combined content these compounds is 2 to 30 vol. %, and the isooctane, which represents a particularly preferred embodiment, typically stands for a content of 5 to 20 vol. %.
[0058] In addition to isoolefins, the present gasoline fuel composition can contain various amounts of paraffines, in particular isoparaffines. The latter are incorporated in amounts of 0.1 to 20 vol.-% preferably about 1 to 15 vol.-%. According to a preferred embodiment, the total content of isoolefins and isoparaffins is about 2 to 40 vol.-%. Isooctane is a typical isoparaffine, which can be used in up to 20 vol.-%.
[0059] The present fuel can also contain various oxygenates, such as alkanols (alcohols). As specific examples, ethanol and methanol can be mentioned. Ethanol-containing compositions contain ethanol in an amount of 0.01 to less than 6 vol.-%. The same concentration range is applicable to methanol. The alkanols can be derived from renewable sources.
[0060] By limiting the total concentration of olefins and the maximum concentration of light olefins, and further by using oxygenates it is possible to maintain good combustion properties of the gasoline while reducing emissions.
[0061] The concentration of oxygen in the fuel is generally about 0.1 to 5 mass %. Typically, the amount of alkanols is sufficient to provide the gasoline composition with an oxygen content of about 1 to 4 mass-%.
[0062] A fuel according to the present invention exhibits the following characteristics:
[0063] a 10% D-86 distillation point no greater than +150° F. (65.6° C.), in particular less than 140° F. (60° C.);
[0064] a 50% D-86 distillation point no greater than +230° F. (110° C. ), in particular less than 220° F. (104.4° C.);
[0065] a 90% D-86 distillation point no greater than +375° F. (190.6° C.), in particular less than 370° F. (187.8° C.); and
[0066] a Reid Vapor Pressure less than 9.0 psi (62 kPa), in particular less than 8.5 psi (58.6 kPa).
[0067] Based on experimental data, the particulate matter emissions were 50% lower than those of a conventional CARB II fuel, and the emissions of THC, NOx, CO and CO 2 were on the same level or lower as for CARB II fuels.
[0068] The experimental results shown below indicate that it is fully possible to provide gasoline compositions which are free from water-soluble and which, nevertheless, meet even stringent requirements for low emissions, by increasing the concentration of heavy olefins and by simultaneously reducing the concentration of light olefins.
[0069] The following, non-limiting example will elucidate the invention:
EXAMPLE
[0070] The composition of the gasoline is basically determined by the CARB specification. The present invention provides for a modification of that specification by the combined use of heavy olefins and isoparaffines, in particular isooctene and isooctane, optionally with oxygenates, in particular ethanol.
[0071] The exhaust emission tests were carried out with six different fuels. The fuels and their compositions are shown in Table 1 below:
TABLE 1 Compositions of Test Fuels TEST Aromatics FUELS Isooctane Isooctene NExTAME Ethanol MTBE Oxygen w-% Olefins vol-% vol-% RFG X X 2 15 35 ref CARB II X 2 5 25 ref CARB III IO X X 2 5 25 CARB III IOE X X X 2 15 25 IsoOkt X 5 25 IsoOkte X X 15 25
[0072] In RFG, the concentration of TAME was 18 vol.-% and of MTBE 5 vol.-%. In CARB II, the concentration of MTBE was 12 vol.-%.
[0073] In the rest of the fuel compositions, the concentration of isooctane was 11 vol.-% and in CARB III IO and IsoOkte, the concentration of isooctane was 10 vol. %.
[0074] The properties of the isooctane and isooctene components, obtained from the Fortum NExOCTANE pilot plant in Porvoo, Finland, are given in Table 2.
TABLE 2 Properties of isooctane and isooctane components. Property Method Isooctane Isooctane RON ISO 5164 100.5 101.6 MON ISO 5163 98.3 84.6 Vapor pressure [kPa] 15.9 14 Density [kg/m3] 701 729 T10 distillation point [° C.] ASTM D86 98 102 T50 distillation point [° C.] ASTM D86 100 105 T90 distillation point [° C.] ASTM D86 119 117 Olefin content, GC [% by volume] 0.5 97 Aromatics content, GC [% by 0 0 volume] Saturates, GC [% by volume] 99.5 0
[0075] [0075] TABLE 3 Properties of test fuels CARB CARB CARB Code RFG II III IO III IOE IsoOkt IsoOkte Density ISO 12185 kg/m 3 766 742 745 745 736 737 at +15° C. Sulphur ASTM ppm 25 10 11 12 10 9 D 3120 Vapour EN 13016 kPa 62 59 61 63 60 61 Pressure FIA-O ISO 3837 Arom Vol-% 37 27 25 25 25 26 Olef Vol-% 13 5 4 14 3 14 Paraf + Naph Vol-% 38 58 65 55 72 60 Oxygenates Vol-% 12 11 5 6 0 0 Total 100 100 100 100 100 100 C/H-ratio 6.93 6.49 6.45 6.56 6.50 6.59 Content of NMR mass-% 12.70 13.50 13.60 13.50 14.00 13.70 Hydrogen Benzene GC mass-% 0.70 0.37 0.35 0.39 0.34 0.37 EtOH AED Vol-% 5.46 5.36 0.00 0.00 TAME AED Vol-% 5.55 0.02 0.02 0.00 0.00 0.00 MTBE AED Vol-% 4.48 11.09 0.02 0.03 0.03 0.04 Other Vol-% 0.04 0.00 0.00 0.00 Oxygenates Distillation ISO 3405 IBP ° C. 33.4 29.3 35.4 32.9 28.5 33.0 05 til-% ° C. 45.0 42.4 45.0 47.4 43.4 45.6 10 til-% ° C. 54.0 50.5 51.8 52.4 53.6 54.2 20 til-% ° C. 69.3 59.5 59.1 59.3 68.5 67.7 30 til-% ° C. 81.6 68.0 66.6 67.2 81.6 79.8 40 til-% ° C. 92.7 77.5 87.4 85.7 92.7 91.4 50 til-% ° C. 103.0 88.7 101.0 98.9 101.3 100.4 60 til-% ° C. 114.5 101.8 108.3 106.6 108.1 107.3 70 til-% ° C. 126.7 114.8 116.4 114.4 115.2 114.5 80 til-% ° C. 140.4 127.8 127.7 125.2 126.3 125.5 90 til-% ° C. 155.3 147.5 148.5 146.3 147.7 146.8 95 til-% ° C. 165.3 159.6 159.9 158.3 160.5 161.0 FBP ° C. 196.6 189.7 190.1 187.6 189.6 190.7
[0076] Emissions were measured at 22° C. temperature for 6 vehicles using the European cycle for year 2000 (ECE+EUDC). Five of the vehicles have 4-cylinder, 16-valve engines equipped with multi point fuel injection (MPI) and a three-way catalytic converter (TWC). The swept volume of these vehicles A, B, C, D and F was form 1.3 liter to 2.0 liter. One vehicle (E) has the engine with six cylinder and the swept volume of 3.3 liters. Also this vehicle was equipped with multi point fuel injection (MPI) and a three-way catalytic converter (TWC
[0077] EMISSION TESTING—Exhaust emissions and fuel consumption of the vehicles were measured on a chassis dynamometer using the current European test cycle according to 70/220/EEC and its amendments. The test equipment used for exhaust dilution, collection of samples and analysis of samples are in compliance with the specifications of US EPA and directive 70/220/EEC and its amendments.
[0078] SAMPLING AND ANALYSES OF PARTICULATE AND SEMIVOLATILE MATTER—Particulates were collected at Fortum using a high capacity system and at the Technical Research Centre of Finland (VTT) using a similar system. The test procedure, sampling and analyses of particulate and semi-volatile matter was performed in a similar way as described by Kokko et al. [Kokko, J., Rantanen, L., Pentikäinen, J., Honkanen, T., Aakko, P., and Lappi, M., Reduced Particulate Emissions with Reformulated Gasoline, SAE Technical Paper 2000-01-2017, 2000]. Sampling and analytical procedures for the particulate and semi-volatile phases at both Fortum and VTT laboratories are briefly described in Lappi, M., Harmonisation of measuring methods of unregulated exhausts from passenger cars. Results of the Round-robin tests. Final report. VTT Energy Engine Technology. Mobile Research Program. Project 232T. March 1999. 50 p.+App. 119 p.
[0079] THC Emissions—The total hydrocarbon emissions are presented in FIG. 1. The THC emissions from the vehicles using a catalytic converter are with near all of the vehicles tested lower with the gasolines according to the present invention than with the other gasolines.
[0080] CO Emissions—Values presented in FIG. 2 show that, compared to CARB II, the carbon monoxide emissions are lower for five vehicles for CARB III IOE, whereas they are somewhat higher for ISO-OKTE. This confirms that the effect of oxygen in gasoline can be significant when reducing CO emissions especially in vehicles without closed loop fuel control systems.
[0081] NO x Emissions—Generally, gasoline with oxygenates slightly increases NO x emissions, and this was also found to be the case in this study, but lower for the gasolines according to the present invention compared to CARB II with all cars tested.
[0082] CO 2 Emissions and fuel consumption—The carbon dioxide emissions and gasoline consumption of the test vehicles are presented in FIGS. 4 and 7. CO 2 emissions from all the gasolines are almost equal and the possible differences are within the confidence interval. All the differences fall within the confidence interval. Fuel consumption for the fuels with no oxygenates were lower than with oxygenates as expected.
[0083] Non-controlled emissions—With the two test cars (E and F) also the amount of so called non-controlled exhaust emissions were measured (FIGS. 8 to 13). From the figures can be seen that the results are more depending on the car measured than on the fuel tested. And no big differences cannot be seen.
[0084] PARTICULATE MASS EMISSIONS—The average particulate mass emissions at 22° C. with the two fuels and all vehicles are given in FIG. 6. Results are presented as average values derived from three or four tests on each fuel. Confidence intervals for these mean values are shown at the 95% level. With catalyst equipped vehicles the amount of particulate mass collected on the filters is very small compared to the weight of blank filters and thus the standard deviation of the results is rather high. Therefore the confidence intervals are quite large. Nevertheless, the gasolines according to the present invention have extremely low particulate mass emissions compared to all other gasolines, including CARB II. The toxic and mutagenic promerties of the particulate matter of the exhaust gases from the two test cars are represented in FIGS. 14 to 17 . It can be seen that toxicity and the mutagenicity of the particulates with the fuel of the present invention were lower when compared to CARB II with all cars tested.
[0085] As the above test results, it is fully possible to replace MTBE in gasoline with heavy olefins without impairing the air quality of exhause gases. | The present invention provides a new gasoline fuel composition, having in combination an octane value (R+M)/2 of at least 85; an aromatics content less than 25 vol. %; and a water-soluble ethers content of less than 1 vol. %. The composition has a content of olefins, at least 10 % of which is formed by heavy olefins having a boiling point above +90 “C. In particular, the composition contains up to 40 % olefins, and it contains less than 6 vol.-% of light olefins having a boiling point below +90° C., and at least 1 vol.-% heavy branched olefins having a boiling point above +90° C. Reductions in emissions of pollutants can be obtained by introducing into an automotive engine an unleaded gasoline having a composition according to invention, combusting the unleaded gasoline in said engine; introducing at least some of the resultant engine exhaust emissions into the catalytic converter; and discharging emissions from the catalytic converter to the atmosphere. | 2 |
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The invention relates in general to an apparatus for monitoring data from a subterranen well to provide current production information.
2. DESCRIPTION OF THE PRIOR ART
In order to determine production characteristics from a subterranean well, it is necessary to know the values of various temperature and pressure parameters. These parameters have been monitored by positioning transducers at selected points downhole, at the wellhead, at the fluid separator, and the like. Previously, the values of these characteristics were recorded by hand at the well site and utilized, along with hand calculations of additional characteristics, to determine the condition and production capability of the well. Such a method is subject to human error and delay and decreased reliability of the information. Some improvement in the quality of the information has been achieved by recording the characteristics values on strip chart recorders.
SUMMARY OF THE INVENTION
The present invention relates to an automatic test monitoring system for a subterranean well. Pressure and temperature transducers are positioned at selected locations and are connected to filter circuits for generating signals respresenting the values of the well operating characteristics. The filter circuits supply the characteristic signals to a data acquisition system which includes a microcomputer control, keyboard and display.
The keyboard is utilized to manually enter characteristic values for start-up and test purposes, in the desired format for reporting characteristic values. The microcomputer directs the monitoring of the characteristics, performs selected calculations to generate additional characteristic values, and controls the output of the monitored and calculated characteristic values to a record/print system. The microcomputer memory is protected against power failure by an input voltage monitoring circuit which automatically switches to battery power when the primary power source is interrupted. Although no new data is acquired, the stored data is saved.
The output signals from the data acquisition system are inputs to a record/print system. This system includes a tape recorder for recording all of the received characteristic values and a printer for recording operator selected ones of the characteristic values. The printer format and print intervals are selected through the keyboard in the data acquisition system. The record/print system includes a microcomputer which receives the instructions from the data acquistion system and controls the tape recorder and printer. This microcomputer is also responsive to a power failure for saving stored data.
An edit system reads the tapes produced by the record/print system and permits an operator to edit the data, re-record the data and print selected reports. Operator commands are entered through a keyboard into a microcomputer. The microcomputer reads the original tape and produces a print-out on a printer. The operator reviews the print-out and enters revisions through the keyboard. The microcomputer responds by recording the revised and unchanged original data on a new tape. The data on the new tape can also be printed and or sent to a remote computer over a telephone line.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an automatic test data system according to the present invention for monitoring both a separator system and bottom hole operating characteristics for a subterranean well.
FIG. 2a is a block diagram of the data acquisition system of FIG. 1.
FIG. 2b is a partial block diagram, partial schematic of the power supply monitor, the clock circuit, and the filter circuits of FIG. 1.
FIG. 3 is a block diagram of the record/print system of FIG. 1.
FIG. 4 is a block diagram of the edit system of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
There is shown in FIG. 1 an automatic test system 10 for monitoring a predetermined set of operating characteristics associated with subterranean wells. The system automatically monitors and compiles data and performs calculations which enable an operator to evaluate the performance of the well.
Typically, the majority of the characteristics sensed by the system are associated with the separator system of the well. The system includes a plurality of separator system transducers 12 which generate signals on lines 14, each signal representing one of the characteristics to be monitored. The following table (Table 1) is an example of several separation system characteristics which can be monitored, along with the model number and manufacturer of a suitable transducer which can be used for monitoring the particular characteristic.
TABLE 1______________________________________LIST OF MEASUREDCHARACTERISTICS AND TRANSDUCERS Characteristic Transducer (Manufacturer)______________________________________(1) Wellhead pressure Model 753-1 Gage Pressure Electronic Transmitter (ITT Barton, 900 S. Turnbull, Canyon Rd., City of Industry, California 91749)(2) Wellhead temperature Model 393 Electronic Temperature Transmitter (ITT Barton)(3) Gas temperature Model 393 Electronic Temperature Transmitter (ITT Barton)(4) Oil temperature Model 393 Electronic Temperature Transmitter (ITT Barton)(5) Gas differential pressure Model 752-1 Differential Electronic Pressure Transmitter (ITT Barton)(6) Static separator pressure Model 753-1 Gage Pressure Electronic Transmitter (ITT Barton)(7) Oil flow Model PLZC-2A1S-2E6C 2" ANSI 600 Ball Vortex Flowmeter (Ball Manufacturing, 903 W. Center, North Salt Lake, Utah 84054)(8) Water flow Model PLZC-2A1S-2E6C 2" ANSI 600 Ball Vortex Flowmeter (Ball Manufacturing)______________________________________
The signals on the lines 14 are supplied to a plurality of filter circuits 16. The circuits 16 filter the transducer signals and generate output signals to a data acquisition system (DAS) 20 on lines 18. The DAS 20 transmits the data on lines 22 to a record/print system 24 where the data is recorded on a suitable storage device such as a magnetic tape. The DAS 20 also performs calculations on the incoming data to generate the values of addtional operating characteristics which assist the operator in evaluating the performance of the well. Examples of calculations which can be performed by the DAS 20 include the gas flow rate, total gas produced, total oil produced, total water produced, and the gas/oil ratio.
An AC power supply monitor 26 senses the AC power to the system 10 and generates power failure warning signals on lines 28 to the DAS 20 when the AC power falls below a suitable operating voltage. As will be discussed, the warning signals alert the DAS 20 to store all the pertinent data in a memory circuit having its own backup battery.
A clock circuit 30 generates a real time signal on lines 32 to the DAS 20 which utilizes the signal to perform such calculations as flow rate and per day outputs. As will be discussed, the circuit 30 includes backup battery for maintaining the realtime signal in the event of a system power failure.
After the data and calculations have been recorded on a storage device, the storage device can be manually transferred to an edit system 34 where an operator can examine the data, revise the data, and add comments. This manual transfer of the storage device is represented by a dashed line 36.
In addition to monitoring a plurality of separation system characteristics, the automatic test system 10 can also monitor bottom hole characteristics, such as bottom hole temperature and bottom hole pressure. A plurality of downhole or bottom hole transducers 38 generate signals on lines 40, each representing one of the bottom hole parameters being measured. The filter circuits 16 then condition the signals before transmitting them to the DAS 20. Monitoring both wellhead and bottom hole parameters permit the DAS 20 to perform a reservoir evaluation on the well by determining the pressure and temperature gradients of the well. Also, the bottom hole transducers can further signal the condition of the well by shutting off the well and measuring the length of time necessary for the well to build up to a maximum static pressure.
There is shown in FIG. 2a a simplified block diagram of the data acquisition system 20. The data acquisition system 20 includes a microprocessors unit (MPU) 50 for controlling the communication of the DAS 20 with the other components of the system 10. The MPU 50 communicates with the other DAS 20 components by means of a backplane 52. The backplane 52 provides connections between the various components of the DAS 20 with lines carrying control signals, address and data busses, and the required power and ground lines. The instructions for controlling the operations of the MPU 50 are stored in a pair of eraseable programmable read-only memories (EPROM) 54 and 56 connected to the backplane 52.
An arithmetic processing unit (APU) 58 is connected to the backplane 52 and is utilized by the MPU 50 to perform arithmetic calculations. The APU 58 receives instructions and data from the MPU 50 via the backplane 52. When the calculations are completed, the MPU 50 will take the results from the APU 58 and transfer them to another location.
A CMOS random access memory (RAM) 60 is connected to the backplane 52 and is utilized to provided backup memory for the system in the event of a power failure. The CMOS RAM 60 is backed up by a rechargable battery (not shown) which has the capacity to hold data in the memory for several weeks after the main power has failed. The RAM 60 includes a trickle charge circuit (not shown) for maintaining the battery in a fully charged state when the main power supply is operating.
An operator can communicate with the DAS 20 by means of a keyboard 62. The keyboard 62 is connected to a parallel input/output (I/O) circuit 64 which supplies inputs to the MPU 50 through the backplane 52. The keyboard is also connected directly to the MPU 50 to signal the MPU when the keyboard is in operation. The operator uses the keyboard to supply specific instructions to the MPU 50, as well as for entering constants of the system to be used in the calculations.
The data and the calculations compiled by the MPU 50 can be transmitted to a video monitor driver 66 and a video memory 68. Since very high speed is required in the communications between the driver 66 and the memory 68, the two units are connected directly together so that they can communicate without using the backplane 52. The driver 66 is also connected for direct communication with the parallel I/O circuit 64. The driver 66 produces a composite video signal which is supplied to a cathode ray tube (CRT) monitor 70. The monitor 70 then displays the information for visual inspection by the operator. The keyboard 62 enables the operator to select the specific data which is to be displayed.
In addition to visually displaying the data and the calculations, the DAS 20 transmits this information to the record/print system 24 where the information can be stored on a magnetic tape and a print-out is produced for the operator. The information is supplied to the record/print system 24 through a serial/parallel I/O circuit 72 and a fiber-optic modem 74. The I/O circuit 72 transmists data received from the MPU 50 on the backplane 52 to the modem 74 on lines 76. The modem 74 converts the electrical data on the lines 76 into optical data and then sends the transformed data to the record/print system 24 on the fiber-optic lines 22. As will be discussed, the record/print system includes a modem for converting the optical data back to electrical data for the recorder and printer.
The main reason for transmitting data in optical form between the DAS 20 and the record/print system 24 is the safety aspects of the system which must be considered when operating electronic equipment in the vicinity of flammable materials. Typically, the DAS 20 and the record/print system 24 will be housed in separate cabinets, and thus the lines 22 will be exposed. Transmitting the data on the lines 22 in optical form increases the safety of the system. If the DAS 20 and the record/print system 24 were housed in a single cabinet, or the system 10 was sufficiently isolated from the flammable materials, the fiber-optic modems could be eliminated and the information could be transmitted between the DAS 20 and the system 24 in electrical form.
In addition to outputting data to the record/print system 24, the I/O circuit 72 is also utilized to receive incomming data. The circuit 72 is connected to receive the real time signal on the lines 32 from the clock circuit 30. The I/O circuit 72 also includes individual counters which are utilized to count a pulsed transducer output signal on a line 18b (one of the lines 18). Several of the transducers generate a pulse train as an output signal, while other transducers generate an analog output signal.
The DAS 20 includes an A/D converter 77 connected to a line 18a (one of the lines 18) to receive data from a transducer having an analog output signal. The A/D converter also receives a signal on a line 28a (one of the lines 28) representing the system AC voltage level, and another signal on a line 78 representing the transducer DC voltage level.
All of the components of the data acquisition system 20 shown in block diagram form in FIG. 2a can be commerically available components. The following table (Table 2) is a list of the DAS 20 components, along with the model number and manufacturer of each component, which may be utilized.
TABLE 2______________________________________COMPONENTS OF DATA ACQUISITION SYSTEMComponent Model Number (Manufacturer)______________________________________(1) MPU 50 Module 1015 (Adaptive Science Corporation, 4700 San Pablo Avenue, Emeryville, California 94608)(2) Backplane 52 Module 1912 (Adaptive Science Corp.)(3) EPROMs 54 and 58 Module 1400 (Adaptive Science Corp.)(4) APU 58 Module 1200 (Adaptive Science Corp.)(5) CMOS RAM 60 Module 1520 (Adaptive Science Corp.)(6) Keyboard 62 IEE thinswitch No. 2500-02(7) Parallel input/output 64 Module 1300 (Adaptive Science Corp.)(8) Video monitor driver 66 Module 1700 (Adaptive Science Corp.)(9) Video memory 68 Module 1701 (Adaptive Science Corp.)(10) CRT Monitor 70(11) Serial/parallel I/O Module 1140 (Adaptivewith counters 72 Science Corp.)(12) Fiber-optic modem 74 Canoga Data Systems Model CRS-100-S(13) A/D converter 77 Module 1642 (Adaptive Science Corp.)______________________________________
There is shown in FIG. 2b a circuit schematic of the AC power supply monitor 26, the filter circuits 16, and the clock circuit 30. The AC power supply monitor 26 includes a full wave bridge rectifier 79 constructed of four diodes connected to receive a VAC alternating voltage signal generated across lines 80 and 82. The VAC voltage signal is typically a lower tap output of the main power transformer having a voltage level directly proportional to the voltage level of the main power signal. The rectifier 79 converts the AC signal across the lines 80 and 82 into a DC signal on a line 84 having a voltage level directly proportional to the AC signal level.
The line 84 is connected to the anode of a diode 86 having a cathode connected to the ground potential through a capacitor 88. A pair of resistors 90 and 92 are connected between the cathode of the diode 86 and the ground potential. The junction between the resistors 90 and 92 is connected to the line 28a which is connected to the A/D converter 77.
A capacitor 94 is connected between the line 84 and the ground potential. A resistor 96 and a potentiometer 98 are connected in series between the line 84 and the ground potential The potentiometer 98 has a variable terminal connected to the ground potential.
The signal on the line 84 is supplied through a resistor 100 as an input to a Schmitt trigger 102 having an output connected to a line 28b (one of the lines 28 of FIG. 1). The output of the trigger 102 is also supplied through a resistor 104 as an input to a Schmitt trigger 106. A diode 108 has an anode connected to the input of the trigger 106 and a cathode connected to the line 28b. A capacitor 110 is connected between the input of the trigger 106 and the ground potential.
The Schmitt trigger 106 generates an output signal which is supplied to the gate of a MOSFET transistor 112 through another Schmitt trigger 114. The transistor 112 has a drain connected to a line 28c (one of the lines 28 of FIG. 1), and a source connected to the ground potential.
The monitor 26 generates three separate signals to the data acquisition system 20, a MPU power failure warning signal on the line 28b, a memory shut off signal on the line 28c, and an AC level signal on the line 28a.
When the power is present on the lines 80 and 82, the AC signal on the lines 84 is supplied through the diode 86 to charge the capacitor 80 to a DC level directly proportional to the level of the monitored AC signal. This DC signal is supplied through the resistor 90 to the A/D converter 77 on the line 28a. The MPU 50 can then monitor the VAC signal level to check whether the signal level is within predetermined acceptable limits. If the VAC signal should fall outside the accepted range, the MPU 50 can signal the operator that certain data was obtained when the VAC signal level was outside the limits and therefore, this data may not be valid.
The DC signal on the line 84 is also used to charge the capacitor 94, which is typically of a lower value than the capacitor 88. As long as the level of the signal on the line 84 remains above the lower trigger level of the Schmitt trigger 102, the trigger will generate a logic "0" near ground potential on the line 28b to signal the MPU 50 that the power supply is operating. The logic "0" signal on the line 28b is also supplied through the resistor 104 to the Schmitt trigger 106. The trigger 106 generates a logic "1" signal which causes the Schmitt trigger 114 to generate a logic "0". The logic "0" signal at the gate of the transistor 112 maintains the transistor 112 in an off condition such that the signal on the line 28c remains at the high logic level. When the signal on the line 28c is at the high level, the CMOS RAM 60 can be accessed by the MPU 50.
When the VAC signal fails, the capacitor 94 will discharge through the resistor 96 and the potentiometer 98. The discharge rate of the capacitor is determined by the component values of the capacitor 94 and the resistor 96, and the effective resistance of the potentiometer 98. When the signal on the line 84 falls below the lower trigger level, the output of the trigger 102 changes from logic "0" to logic "1" to signal the MPU 50 of the power failure. The MPU 50 will then take all the outstanding pertinent data and store that data in the CMOS RAM 60.
The logic "1" signal on the line 28b is also supplied through the resistor 104 to charge the capacitor 110. When the capacitor 110 has charged to a higher trigger level of the trigger 106, the trigger will generate a logic "0" signal which causes the trigger 114 to generate a logic "1" signal to turn on the transistor 112. This pulls the line 28c to near ground potential, which is logic "0". A logic "0" on the line 28c prevents access to the RAM 60 by the MPU 50, and thus projects the memory until the power is restored.
When the AC power is restored, the capacitor 94 is recharged to trigger the output of the trigger 102 to a logic "0". This causes the capacitor 110 to discharge through the diode 108 and the Schmitt triggers 106 and 114 turn off the transistor 112. Thus, the lines 28b and 28c will return to logic "0" and "1" respectively, indicating that the power supply is operating.
As previously mentioned, the transducer output signals are supplied to filter circuits before they are sent to the data acquisition system 20. It should be noted that the transducers can generate different types of output signals representing the measured parameter. For example, the pressure and temperature transducers listed in TABLE 1 each generate an output signal having a DC current level directly porportional to the measured parameter. On the other hand, the flow meter transducers of TABLE 1 generate a pulsed output signal, with each pulse representing a predetermined amount of fluid flow. FIG. 2b shows two different filter circuits, a filter circuit 16a which receives a direct current signal on a line 14a (one of the lines 14) from either a pressure or temperature transducer, and a filter circuit 16b which receives a pulsed signal on a line 14b (one of the lines 14) from a flow meter transducer. It should be noted that, although only two filter circuits shown in FIG. 2b, the system 10 typically includes a separate filter circuit for each transducer. The particular type of filter circuit used is dependent on the type of output signal generated by the associated transducer.
The filter circuit 16a includes a safety barrier 116 which is connected to receive a transducer output signal on the line 14a. The safety barrier 116 permits passage of a desired signal or current, but restricts current flow under fault conditions to a safe level. This prevents sparking in the potentially dangerous area.
A resistor 118 and a capacitor 120 are connected in parallel between the output of the barrier 116 and the ground potential. An inductor 122 and a resistor 124 are connected in series between the output of the safety barrier 116 and the line 18a (one of the lines 18). A capacitor 126 is connected between the junction of the inductor 122 and the resistor 124 and the ground potential. Another capacitor 128 is connected between the line 18a and the ground potential.
The resistor 118 is typically a precision resistor such that the voltage level at the output of the barrier 116 is a DC level directly proportional to the value of the measured characteristic. The inductor 122, the resistor 124, and the capacitors 120, 126, and 128 constitute a low pass filter which eliminates noise on the line 14a before generating the filtered output signal on the line 18a. The MPU 50 will then periodically read each transducer signal supplied to the A/D converter 77.
The filter circuit 16b receives a pulsed transducer output signal on the line 14b (one of the lines 14) which is connected to the input of the barrier 130. The output of the barrier 130 is connected to the cathode of a zener diode 132 having an anode connected to the ground potential. A capacitor 134 is connected between the output of the barrier 130 and the ground potential. An inductor 136 and a resistor 138 are connected in series between the barrier output and the input of a Schmitt trigger 140. A capacitor 142 is connected between the junction of the inductor 136 and the resistor 138 and the ground potential. Another capacitor 144 is connected between the input of the trigger 140 and the ground potential. The output of the trigger 140 is connected to line 18b, which is one of the lines 18 of FIG. 1. The line 18b is connected to the I/O circuit 72.
The zener diode 132 functions to clamp the amplitude of the output of the barrier 130 in the event the input signal exceeds the normal input voltage allowed by the Schmitt trigger 140. The inductor 136, the resistor 138, and the capacitors 134, 142, and 144 constitute a low pass filter to reduce noise in the signal before it is supplied as an input to the Schmitt trigger 140. Each time a pulse is received by the filter circuit 16b, the trigger 140 will generate an output pulse on the line 18b to increment one of the counters in the circuit 72. The MPU 50 will then read the counter periodically to determine the total volume of flow. Since the MPU also receives a real time signal from the clock circuit 30, the MPU can also calculate the flow rate of the fluid sensed by the respective transducers.
Typically, the transducers are connected to receive a power supply signal. In FIG. 2b, a VDC power supply (not shown) generates a +VDC signal through safety barriers 146 on a line 148 to the transducers. A voltage divider consisting of serially connected resistors 150 and 152 is connected between the VDC power supply and the ground potential. The line 78 is connected between the resistors 150 and 152 to generate a reduced voltage level signal to the A/D converter 77. The MPU 50 can then monitor the performance of the VDC power supply to ensure that the voltage does not exceed the voltage limits of the safety barriers 146 and that adequate voltage is supplied to the transducers. If excessive power source fluctuation occurs, the MPU 50 generates a power fluctuation signal to the video monitor driver 66 for display on the CRT monitor 70 and to the record/print system 24 for recording on a tape with the other data.
As previously mentioned, the clock circuit 30 generates a real time signal on the line 32 to the MPU 50 through the I/O circuit 72. The clock circuit 30 includes a voltage regulator 156 having an input connected to the VDC power supply. A filter capacitor 158 is connected between the regulator input and the ground potential. A resistor 160 is connected between the regulator input and a ground input of the regulator. A diode 162 has an anode connected to the ground input of the regulator and a cathode connected to the ground potential.
The output of the voltage regulator 156 is supplied through a pair of diodes 164 and 166 to provide power to a one Hz oscillator 168 and a sixteen bit binary counter 170 on a line 171. The oscillator increments the counter 170 once each second to produce a count representing the real time. A filter capacitor 172 is connected between the output of the regulator 156 and the ground potential.
The output of the regulator 156 is also connected to the anode of a light emitting diode (LED) 174 having a cathode connected to the ground potential through a resistor 176. A resistor 178 is connected between the cathode of the LED 174 and a line 180 which is connected to an input 182-2 of an AND gate 182. The AND gate 182 has a second input 182-1 connected to one of the sixteen output lines of the counter 170. The AND gate 182 is representative of sixteen such AND gates each having one input connected to receive a separate one of the counter output signals, and a second input connected to receive the signal on the line 180. The AND gate 182 has an output 182-3 connected to one of the lines 32 to supply the counter output to the I/O circuit 72.
A resistor 184 is connected between the output of the regulator 156 and the anode of a diode 186 having a cathode connected to the positive terminal of a DC backup battery 188. The negative terminal of the battery 188 is connected to the ground potential. A diode 190 has an anode connected to the positive terminal of the battery 188 and a cathode connected to the line 171.
When the voltage regulator 156 is operating properly, a positive DC voltage signal is generated at its output to forward bias the diodes 164 and 166 and apply a DC signal on the line 171 to the oscillator 168 and the counter 170. The oscillator 168 generates an output pulse each second to increment the counter 170. The DC voltage signal generated by the regulator 156 is supplied to light the LED 174 to indicate that the regulator is operating properly. When the LED 174 is on, the cathode of the LED 174 will be near the DC voltage signal level. This high level signal is supplied through the resistor 178 as a logic "1" signal to the input 182-2 of the AND gate 182. This enables the AND gate 182 to supply the counter output of the I/O circuit 72. The regulator 156 maintains the battery 188 in a fully charged state by supplying a charge current through the resistor 184 and the diode 186.
In the event the VDC power supply is interrupted, the DC voltage signal at the output of the regulator 156 will drop and the diodes 164 and 166 will become reverse biased. The diode 190 is then forward biased such that the backup battery 188 supplies a DC voltage signal on the line 171 to power the oscillator 168 and the counter 170. Also, when the regulator voltage drops, the LED 174 will turn off such that its cathode will be at ground potential. This ground signal is supplied through the resistor 178 as a logic "0" to the AND gate input 182-2. This disables the AND gate and prevents the counter output signal from being supplied to the I/O circuit 72 when the VDC power supply is down. Thus, in the event of a power failure, the counter 170 will maintain a real-time count such that when power is restored, the system will recognize that a power interrupt has occured. The operator can then input data to the system so that a maximum of continuity can be realized in operating the system.
There is shown in FIG. 3, a simplified block diagram of the record/print system 24. The controller of the system 24 is an MPU 200 connected to receive operating instructions from a PROM 202 through a backplane 204. The MPU 200 transmits and receives data from the other components of the system 24 through a serial input/output circuit 206. The backplane provides the connections between the MPU 200, the I/O circuit 206, and the PROM 202 required to carry the control signals, the address and data busses, and the power and ground lines.
The system 24 also includes a fiber-optic modem 208 for receiving data in optical form from the DAS 20 on the fiber-optic lines 22. The modem 208 converts the optical data on the lines 22 into an electrical form and then sends the transformed data to the I/O circuit 206 on lines 210. The MPU 200 receives this data via the backplane 204.
The MPU 200 outputs data received from the DAS 20 through the I/O circuit 206 to a tape controller 212. The controller 212 then records the data on a magnetic tape #1 214. After the tape #1 becomes full, the system will automatically switch to recording the data on a tape #2 216. The tapes 214 and 216 can be changed periodically to provide additional storage. The MPU 200 also includes RAM temporary storage for data.
The MPU 200 also transmits data received from the DAS 20 through the I/O circuit 206 to a printer 218. The printer 218 provides a printout which then can be examined by the operator. Typically, the operator will not want all the data received from the DAS 20 to be printed by the printer. The keyboard 62 of the DAS 20 (FIG. 2a) allows the operator to select the specific data and time intervals for printing. These instructions can then be supplied to the MPU 200 via the lines 22.
All of the components of the record/print system 24 shown in block diagram form in FIG. 3 can be commercially available components.
The following table (Table 3) is a list of the record/print system 24 components, along with the model number and manufacturer of each component, which can be utilized.
TABLE 3______________________________________COMPONENTS OF THE RECORD/PRINT SYSTEMComponent Model Number (Manufacturer)______________________________________(1) MPU 200 Module 1015 (Adaptive Science Corporation)(2) PROM 202 Module 1416 (Adaptive Science Corp.)(3) Backplane 204 Module 1904 (Adaptive Science Corp.)(4) Serial input/ Module 1180 (Adaptive output circuit 206 Science Corp.)(5) Fiber-optic modem 208(6) Tape controller 212 TU-58 Recorder (Digital Equipment Corporation)(7) Printer 218 Model 743 Electronic Data Terminal (Texas Instruments Incorporated, P.O. Box 1444, Houston, Texas 77001)______________________________________
There is shown in FIG. 4 a simplified block diagram of the edit system 34. After a tape has been recorded with data in the record/print system, the record tape is transferred to the edit system where the recorded data can be examined by the operator. The operator can then delete any unnecessary data and add data and comments. A new tape with the revised data can then be produced.
The controller of the edit system 34 is an MPU 220 connected to receive operating instructions from a PROM 222 through a backplane 224. The MPU 220 transmits and receives data from the other components of the system 34 through a serial input/output circuit 226. The backplane 224 provides the connections between the MPU 220, the I/O circuit 226, and the PROM 222 required to carry the control signals, the address and data busses, and the power and ground lines.
The MPU 220 will read a source tape 228 through the I/O circuit by means of a tape controller 230. The source tape 228 is one of the magnetic tapes 214 or 216 (FIG. 3) which has been recorded with data by the record/print system. The data read from the source tape 228 by the MPU 220 is then transmitted to a keyboard/printer unit 232 where the data is printed for examination by the operator. The operator can then use the keyboard of the unit 232 to instruct the MPU 220 to delete unnecessary data and/or add data. The operator can also add comments to the remaining data. The MPU 220 will then transmit the revised data to the tape controller 230. The controller 230 then records the revised data on a final tape 234 and the original or source tape is left intact.
All of the components of the edit system 34 shown in block diagram form in FIG. 4 can be commercially available components. The following table (Table 4) is a list of the edit system 34 components, along with the model number and manufacturer of each component, which can be utilized.
TABLE 4______________________________________COMPONENTS OF THE EDIT SYSTEMComponent Model Number (Manufacturer)______________________________________(1) MPU 220 Module 1015 (Adaptive Science Corporation)(2) PROM 222 Module 1416 (Adaptive Science Corp.)(3) Backplane 224 Module 1904 (Adaptive Science Corp.)(4) Serial input/ Module 1120 (Adaptiveoutput circuit 226 Science Corp.)(5) Tape controller 230 TU-58 Recorder (Digital Equipment Corporation)(6) Keyboard/printer Model 745 Electronicunit 232 Data Terminal (Texas Instruments Incorporated)______________________________________
In summary, the present invention concerns an apparatus in the testing of a subterranean well. A plurality of surface and downhole transducers are utilized to generate signals representing operating characteristics of the well. The apparatus includes means connected to the transducers for periodically storing values of the transducer signals, means for reading at least one of the stored values to generate a value for an additional operating characteristic of the well, and means for generating a plurality of output signals representing the stored values and the additional operating characteristic value. The means for storing can include a random access memory, the means for reading can include a microprocessor unit and an arithmetic processing unit, and the means for generating can include the microprocessor unit and an output circuit. The microprocessor unit, the random access memory, the arithmetic processing unit, and the output circuit can all be connected to a backplane for intercommunication.
Although the invention has been described in terms of specified embodiments which are set forth in detail, it should be understood that this is by illustration only and that the invention is not necessarily limited thereto, since alternative embodiments and operating techniques will become apparent to those skilled in the art in view of the disclosure. Accordingly, modifications are contemplated which can be made without departing from the spirit of the described invention. | An apparatus for monitoring the testing of a subterranean well by acquiring data from the well includes means for monitoring transducers positioned downhole, at the wellhead, at a separator or at other locations to obtain the values for a predetermined set of operating characteristics. The apparatus includes a microcomputer for calculating additional characteristics utilizing one or more of the transducer values and a visual display for onsite viewing of the values for the monitored and calculated characteristics. The apparatus further includes a printer and a tape recorder. The microcomputer controls the recording intervals of the printer and the tape recorder for recording the monitored and calculated values of the characteristics on a continuous basis. The values of the characteristics represent current production information for the well. The apparatus also includes means for monitoring the transducer power supply voltage and the microcomputer power supply voltage. If the microcomputer power supply fails, a backup battery is automatically connected to power a storage means for preserving the values of the operating characteristics for a predetermined time. | 4 |
RELATED APPLICATION
[0001] The present application is a continuation-in-part of the Applicant's U.S. patent application Ser. No. 08/612,093, entitled “Device For Collecting A Blood Sample From A Plastic Segment Tube”, filed on Ma. 2, 1996.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention.
[0003] The present invention relates generally to the field of devices for collecting blood samples. More specifically, the present invention discloses a device for safely piercing a plastic segment tube to release a blood sample into a receptacle for subsequent testing.
[0004] 2. Statement of the Problem
[0005] Donated blood is widely used for transfusions to assist patients suffering trauma and during surgery. A soft plastic bag called a blood collection bag is used for gathering blood from the donor. The blood collection bag is connected to a flexible plastic tube and a needle at the distal end of the plastic tube is penetrated into the donor's vein. Blood flows through the needle and tube into the blood collection bag. After the desired quantity of blood has been collected in the blood collection bag, the needle is withdrawn and the tube is heat sealed into a series of segments containing the donor's blood.
[0006] Prior to transfusion, each unit of blood must be tested to ensure that it is compatible with the patient's blood type. This is commonly referred to as a “type and cross-match” procedure. In addition, donated blood is often tested for the presence of infectious agents, such as hepatitis viruses and HIV. However, blood samples cannot be obtained directly from the blood collection bag, because of potential contamination of the blood that may occur from contact with a syringe or pipette used to withdraw a sample.
[0007] As a result of this problem, the conventional approach has been to heat seal a number of short segments of the plastic tube leading from the donor's arm to the blood collection bag. These sealed tube segments are commonly referred to as segment tubes, pigtails, or segments. The segment tubes are made of soft plastic that can easily bend or buckle. The segment tubes remain attached to the blood collection bag, and are often folded into a group held together with a rubber band. Blood is typically tested shortly after it has been donated, and again immediately before transfusion. In both cases the laboratory technician simply removes one of the segment tubes attached to the blood collection bag for testing. The customary technique is to use a pair of surgical scissors to cut the segment tube in half at the junction between the sedimented red blood cells and plasma in the blood sample within the segment tube. The section of the segment tube containing the red blood cells is then squeezed to force cells into a test tube for subsequent testing.
[0008] This current technique has a number of shortcomings and potential hazards. The segment tube may be under internal pressure, which can cause blood to spray outward when the segment tube is cut. This can expose the technician and work surfaces in the laboratory to potential blood contamination. The scissors also become contaminated with blood, and could cause transmission of blood-borne infectious disease to health care workers, particularly if the technician experiences an injury from sharp edges associated with the scissors. The scissors are often reused without cleaning or sterilization after cutting through a segment tube. This further increases the dissemination of blood-borne microorganisms to work surfaces and drawers where scissors are stored after use. The surface of the donor blood bag can also become contaminated with blood by laying the bag on contaminated work surfaces, or by technicians touching the bag with blood-contaminated gloves or hands. The blood-contaminated blood bag might then contaminate other hospital environments, such as operating rooms and patient areas. Again, this could potentially increase nosocomial and health care worker infection rates from blood contamination (e.g., staphylococcal, streptococcal, hepatitis B and C infections). Finally, failure to clean the scissors between samples could cause subsequent blood samples to be contaminated with trace amounts of blood from preceding samples. This can lead to inaccurate cross-matching, with subsequent safety concerns for patients requiring transfusions. Furthermore, this problem could unnecessarily increase the time and cost for cross-matching and delay transfusion of blood to patients in life-threatening emergencies.
[0009] A number of devices have been invented in the past for piercing segment tubes, including the following:
Inventor Patent No. Issue Date Staebler et al 5,254,312 Oct. 19, 1993 McMorrow 4,176,451 Dec. 4, 1979 Minase et al. EPO Publ. 0350792 Jan. 17, 1990
[0010] “Introducing the SEG-SAFE™ Segment Processor”, Alpha Scientific Corp., Southeastern, Pa. (1995)
[0011] “Directions for Using SegmentSampler™,” Gamma Biologicals, Inc., Houston, Tex. (November 1994).
[0012] Staebler et al. disclose a device for collecting a blood sample from a segment tube. The main body of the device has a cup like portion that is inserted into a test tube. The user then inserts a segment tube into the cup like portion of the device and exerts a downward force to enable a piercing element (i.e., a blade or lance) to puncture the segment tube, thereby allowing blood to flow from the segment tube into the test tube. This device is marketed by Innovative Laboratory Acrylics, Inc., of Brighton, Mich., under the name “I.L.A. Safety Segment Slitter.”
[0013] McMorrow discloses a segment tube cutter with a tapered lower end 8 that is inserted into the test tube 6 . A sharp spur 10 cuts the segment tube 11 as it is inserted into the device.
[0014] Minase et al. disclose another example of a device for piercing segment tubes. The tubular portion 2 of the device is inserted into a test tube. A cutting edge or needle at the bottom of the tubular portion pierces the segment tube as it is inserted. A hole 7 allows blood to drain from the segment tube into the test tube.
[0015] The literature distributed by Alpha Scientific Corp. shows a temporary receptacle for processing segment tubes that includes a needle to puncture the segment tube.
[0016] The “SegmentSampler” device marketed by Gamma Biologicals, Inc., is generally similar to that disclosed by Minase et al. However, the lower tubular portion of the device is tapered to accommodate a range of test tube diameters.
[0017] The prior art devices fail to address many of the technical and safety issues associated with obtaining a blood sample from a segment tube. An ideal blood sampling device should address the following concerns:
[0018] (a) The type and cross-match procedure is commonly performed using any of several different test tubes diameters. It is important that the device be able to accommodate different test tube diameters. In particular, the device should not exert forces on the neck of the test tube as the segment tube is punctured that might cause the test tube to break.
[0019] (b) There are no accepted industry standards for the diameter and thickness of the plastic tubing leading to the blood collection bag. Therefore, the device should be able to accommodate different segment tube diameters.
[0020] (c) Segment tubes are heat-sealed using at least three different heat-sealing devices that result in different shapes and thicknesses of the heat-sealed ends of segment tubes. In addition, each segment tube has two distinct diameters. The sealed ends have a major dimension larger than the diameter of the body of the segment tube. This further complicates the dimensional variations among the various types of segment tubes. A device with a cylindrical opening to receive the segment tube will tend not to provide a particularly good fit, and may not adequately guide and support the segment tube. The device should be able to accommodate sealed ends having a wide range of dimensions without exerting radial forces on the test tube.
[0021] (d) The segment tube should not be allowed to fold or buckle as it is inserted into the device.
[0022] (e) The device should not have an opening that restricts insertion of the segment tube to a particular orientation to accommodate the flat sealed end of the segment tube.
[0023] (f) The device should minimize contact between the users fingers and the glass test tube.
[0024] (g) The device should prevent contact between the user's fingers and the puncturing element within the device.
[0025] (h) After the segment tube has been punctured, the user should not have direct contact with the punctured end of the segment tube to minimize blood splatter and contamination. The device should retain the punctured segment tube so that both can be discarded together.
[0026] (i) Considerable downward force may be necessary to puncture the segment tube. The device should provide sufficient structural support to maintain proper orientation for the puncturing element, and to prevent the puncturing element from bending or being dislodged.
[0027] (j) If adhesive is used to bond the needle to the device, the adhesive should not be permitted to plug the needle and thereby interfere with drainage of blood from the segment tube through the needle into the test tube.
[0028] (k) It is also important to minimize the dispersal of any blood remaining in the device after the segment tube and device have been discarded. Blood tends to remain within the needle and droplets of blood accumulate at the bottom of the device. These droplets of blood can easily become dislodged when the device is discarded and contaminate the surrounding environment.
[0029] Thus, the “egmentSamplee” device marketed by Gamma Biologicals, Inc., has a number of shortcomings when compared against the above list of desired features. In particular, the tapered side walls of the SegmentSampler device create radial pressure if used with smaller test tubes (e.g., 10 mm and 12 mm) that can cause the test tube to break when a relatively small downward force is exerted on the device. Also, the SegmentSampler device is not well suited to receive segment tubes having a wide range of diameters and shapes. Wider segment tubes and those with larger sealed ends create an interference fit that can exert radial pressure on the wall of the test tube and break the test tube when the user pushes downward on the segment tube. This device also provides little structural support for the needle. Hence, the segment tube can bend the needle sideways, preventing puncture of the segment tube. The segment tube could also buckle or fold upon itself without being punctured.
[0030] The device disclosed by Staebler et al. has many of the same shortcomings. In addition, this device uses a solid lancet to puncture the segment tube that also plugs the opening in the segment tube, and thus interferes with the flow of blood into the test tube. Also, the device requires that the flat end of the segment tube be inserted at a predetermined orientation to allow the lancet to pierce the wall of the segment tube.
[0031] 3. Solution to the Problem
[0032] None of the prior art references uncovered in the search show a device having the structure of the present invention. In particular, the present device has a port for receiving the end of the segment tube that includes a plurality of tapered ribs arranged in a radial pattern with slots interspersed between each adjacent pair of ribs. This configuration allows the device to handle a wide range of segment tube diameters and a wide variance in the dimensions of sealed ends. The medial edges of the ribs create a passageway with a smaller diameter for guiding and supporting the tubular portion of the segment tube so that it does not fold or buckle, thereby enabling the segment tube to present onto the puncturing element. Multiple slots allow the sealed end of the segment tube to be inserted in any orientation. The larger dimensions of the slots allow the larger, sealed end of the segment tube to be inserted without causing folding or bending of the segment tube. The ribs also help to retain the segment tube after it has been punctured so that the device and segment tube can be discarded together.
[0033] The segment tube is punctured by the needle above the level of the test tube, and therefore never enters the test tube. As a result, no outward radial forces are exerted on the test tube as the segment tube is inserted into the device.
[0034] An annular recess in the bottom of the device accommodates a wide range of test tube diameters without creating radial stresses that might break the test tube. The annular recess contacts only the top rim of the test tube and only a downward force is exerted on the rim of the test tube when a segment tube is inserted into the device. The lower portion of the device housing serves as a protective skirt covering the rim and upper portion of the test tube to protect the user's fingers if the test tube breaks.
[0035] In addition, the needle is held firmly in place by a horizontal divider 12 , sleeve 18 , and a series of lower radial ribs 21 (see FIG. 11). This additional structural support minimizes deflection of the needle when the segment tube is inserted. The lower ribs 17 below the divider 12 increase capillary attraction of blood that may remain at the bottom of the device after the segment tube has been punctured, so that blood droplets are less likely to contaminate the surrounding environment after the test tube is removed and the device is discarded.
SUMMARY OF THE INVENTION
[0036] This invention provides a device for collecting a blood sample into a receptacle from a plastic segment tube. A cylindrical housing contains a hollow needle that punctures the segment tube as it is inserted into the upper port of the device. A series of ribs with medial edges are arranged in a radial pattern around the needle within the upper port to guide and support the segment tube as it is inserted. The ribs are separated by slots that also guide the sealed end of the segment tube. An annular recess around the lower port of the device holds the rim of the receptacle and allows blood released by the punctured segment tube to drain into the receptacle. The annular recess accommodates a wide range of test tube diameters, and exerts only a downward force on the rim of the receptacle when a segment tube is inserted into the upper port of the device.
[0037] A primary object of the present invention is to provide a device for collecting a blood sample from a segment tube that can accommodate a wide range of segment tube sizes, segment tube end shapes, and test tube diameters.
[0038] Another object of the present invention is to provide a device for collecting a blood sample from a segment tube that does not exert radial forces on the test tube that might cause the test tube to break.
[0039] Another object of the present invention is to provide a device for collecting a blood sample from a segment tube that guides and supports both the tubular portion and sealed end of the segment tube as they are inserted to prevent the segment tube from folding or buckling.
[0040] Another object of the present invention is to provide a device for collecting a blood sample from a segment tube that includes a protective skirt covering the rim and upper portion of the test tube to protect the users fingers in case the test tube breaks.
[0041] Yet another object of the present invention is to provide a device for collecting a blood sample from a segment tube that includes sufficient structural support to prevent the needle from being deflected by the segment tube.
[0042] These and other advantages, features, and objects of the present invention will be more readily understood in view of the following detailed description and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] The present invention can be more readily understood in conjunction with the accompanying drawings, in which:
[0044] [0044]FIG. 1 is a top perspective view of the present device 10 .
[0045] [0045]FIG. 2 is a top view of the device 10 .
[0046] [0046]FIG. 3 is a bottom perspective view of the device 10 .
[0047] [0047]FIG. 4 is a bottom view of the device 10 .
[0048] [0048]FIG. 5 is a side cross-sectional view of the device 10 .
[0049] [0049]FIG. 6 is an exploded side elevational view of a segment tube 50 , the device 10 , and a test tube 60 .
[0050] [0050]FIG. 7 is a side cross-sectional view of the device 10 on a test tube 60 after a segment tube 50 has been inserted into the device 10 .
[0051] [0051]FIG. 8 is a cross-sectional view of the device 10 and segment tube 50 corresponding to FIG. 7 taken through a horizontal plane extending through the needle 15 of the device 10 and the lower end of the segment tube 50 .
[0052] [0052]FIG. 9 is a top perspective view of an alternative embodiment of the present device 10 .
[0053] [0053]FIG. 10 is a side cross-sectional view of the alternative embodiment of the device 10 corresponding to FIG. 9.
[0054] [0054]FIG. 11 is a cross-sectional view of another alternative embodiment of the device 10 .
[0055] [0055]FIG. 12 is a top view of the alternative embodiment of the device 10 corresponding to FIG. 11.
[0056] [0056]FIG. 13 is a bottom view of the alternative embodiment of the device 10 corresponding to FIG. 11.
[0057] [0057]FIG. 14 is another cross-sectional view of the alternative embodiment of the device 10 corresponding to FIG. 11.
DETAILED DESCRIPTION OF THE INVENTION
[0058] Turning to FIG. 1, a top perspective view is shown of the entire device 10 . A corresponding top view is illustrated in FIG. 2. The device 10 has a generally cylindrical housing 11 having an upper port and a lower port. A bottom perspective view is provided in FIG. 3 and a corresponding bottom view is provided in FIG. 4 showing the lower port of the device 10 . FIG. 5 is a side cross-sectional view of the entire device 10 . The housing 11 includes a series of vertical grooves 19 to provide a better grip for the user's fingers.
[0059] As illustrated in FIG. 6, the lower port of the device 10 is first placed over a test tube 60 (or other receptacle) intended to receive the blood sample. A segment tube 50 is then inserted into the upper port of the device. The tubular portion of the segment tube 50 is typically made of flexible plastic that is relatively easy to bend or buckle, as illustrated in FIG. 7. The ends of the segment tube 50 are heat sealed, which results in a crimped or flattened end 51 having dimensions that are larger than the smaller diameter of the tubular portion of the segment tube 50 .
[0060] A series of ribs 14 are arranged in a radial pattern about a hollow needle 15 within the upper portion of the housing 11 . The ribs 14 have tapered medial edges surrounding the needle 15 that define an unobstructed passageway leading downward from the upper port to the needle 15 . This vertical passageway has relatively large cross-sectional dimensions at the upper port that progressively reduce to smaller cross-sectional dimensions adjacent to the needle 15 . In the preferred embodiment, the passageway is a tapered vertical column having a generally circular cross-section with an effective diameter adjacent to the needle 15 that results in a friction fit with the smaller diameter of the tubular portion of the segment tube 50 . Thus, the medial edges of the ribs 14 serve to guide and support the tubular portion of the segment tube 50 as it is inserted into the upper port of the device 10 and punctured by the needle 15 . The ribs 14 also help to prevent the tubular portion of the segment tube 50 from folding or buckling, and help to prevent accidental contact by the user with the sharp point of the needle 15 .
[0061] Slots or spaces 13 between each pair of adjacent ribs 14 catch, align, guide, and support the sealed end 51 of the segment tube 50 as it is inserted so that the segment tube 50 is punctured by the needle 15 . In particular, the slots 13 guide and support the larger dimensions of the sealed end 51 of the segment tube, while the medial edges of the ribs 14 guide and support the smaller diameter of the tubular portion of the segment tube 50 .
[0062] In the preferred embodiment, the slots 13 are radially arranged in diametrically opposed pairs, so that the sealed end 51 of the segment tube 50 can be inserted in any orientation about the vertical axis and yet engage one of the pairs of slots 13 , as shown in FIG. 8. In addition, the ribs 14 and slots 13 guide the segment tube 50 into a vertical position if it is initially inserted at a tilt.
[0063] A floor or divider 12 separates the upper port of the device 10 from the lower port. The base of the hollow needle 15 is held by and extends upward through the divider 12 , thereby providing a passageway to allow blood to drain from the punctured segment tube 50 through the lower port of the device and into the receptacle 60 . The sharp upper point of the needle 15 remains shielded within the housing 11 to prevent accidental contact by the user with the point of the needle 15 . A sleeve 18 supports the lower portion of the needle 15 to prevent bending or buckling. It should also be expressly understood that other means could be substituted for puncturing the segment tube 50 . For example, a solid needle, sharp spur, or blade could be used with a separate conduit through the divider 12 to allow blood to drain into the receptacle 60 .
[0064] The lower port includes an annular recess 16 that receives the rim 61 of the test tube 60 . The width of this annular recess 16 can be made quite substantial to accommodate a wide range of test tube diameters. The lower portion of the cylindrical housing 11 serves as a skirt covering the upper portion of the test tube. This provides support to prevent the device 10 from accidentally flipping or sliding off the test tube 60 . The lower portion of the housing 11 also helps to protect the user's fingers and hand from sharp edges in the event the test tube 60 breaks. It should be expressly understood that other means could be used to temporarily mount the device 10 on the test tube rim 61 . For example, a circular recess or mechanical fasteners could be employed to attach the device 10 to a test tube 60 .
[0065] The present device 10 could also be used without a test tube 60 or other receptacle. For example, the device could be used to obtain a blood specimen directly onto a slide for a blood smear. Optionally, the annual recess 16 could be completely eliminated.
[0066] The base of the needle 15 is surrounded by a series of lower ribs 17 arranged in a radial pattern on the underside of the divider 12 . The exposed surface area of the lower ribs 17 adjacent to the base of the needle 15 provides capillary attraction for any remaining droplets of blood after the test tube 60 is removed, and thereby reduces the risk of contamination to the surrounding area. Furthermore, the lower ribs 17 protrude below the base of the needle 15 , as shown in FIG. 3, and prevent the user's hand or fingers from accidentally coming into contact with the base of the needle 15 .
[0067] In the preferred embodiment, the needle 15 extends upward from the center of the divider 12 along the vertical axis of the housing 11 . The annular recess 16 is also centered about this common vertical axis. As the segment tube 50 is inserted into the upper port of the device 10 , the slots 13 guide and support the sealed end 51 of the segment tube 50 so that it is punctured by the needle 15 . The ribs 14 guide and support the smaller diameter of the tubular portion of the segment tube 50 . Axial alignment of the upper port, needle 15 , and annular recess 16 ensures that only downward forces of any significant magnitude are exerted on the rim 61 of the test tube 60 . It should also be noted that the segment tube 50 is punctured by the needle 15 above the level of the rim of the test tube 60 , as shown in FIG. 7. The segment tube 50 never enters the test tube 60 . As a result, no radial forces are exerted on the test tube 60 as the segment tube 50 is inserted into the device 10 . This feature allows a wide range of test tube diameters to be used without concern of whether the segment tube 50 (or its sealed end 51 ) will fit into the test tube 60 .
[0068] After the segment tube 50 has been punctured, blood drains from the segment tube 50 through the hollow needle 15 into the receptacle 60 , as shown in FIG. 7. The device 10 is then removed from the receptacle 60 , and the device 10 and segment tube 50 are discarded together. As previously mentioned, the medial edges of the ribs 14 create a friction fit with the tubular portion of the segment tube 50 . The needle 15 also tends to retain the punctured segment tube 50 . These frictional forces help to keep the device 10 and segment tube 50 together when they are discarded, and thereby minimize contamination of the surrounding area.
[0069] [0069]FIGS. 9 and 10 are top perspective and cross-sectional views, respectively, depicting an alternative embodiment of the present invention in which the medial edges of the ribs 14 are straight and vertical, unlike the tapered medial edge shown in FIGS. 1 and 5. This would not necessarily be the preferred embodiment because it could be more difficult to insert the segment tube 50 into the device 50 due to the lack of tapering.
[0070] [0070]FIGS. 11 through 14 illustrate another alternative embodiment in which the divider 12 has a different configuration. In this embodiment, the sleeve 18 surrounding the base of the needle 15 is further reinforced by a second set of upper ribs 21 extending from the divider 12 to the sleeve 18 .
[0071] As before, a series of lower ribs 17 surround, but do not touch the base of needle 15 below the divider 12 . The exposed surface area of the lower ribs 17 adjacent to the base of the needle 15 provides capillary attraction for any remaining droplets of blood after the test tube 60 is removed, and thereby reduces the risk of contamination to the surrounding area. The lower ribs 17 extend downward below the base of the needle 15 , as shown in FIG. 11, to prevent the user from accidentally coming into contact with the base of the needle 15 .
[0072] The base of the needle 15 is secured to the sleeve 18 and the remainder of the device by adhesive during the manufacturing process. The lower ribs 17 tend to trap any excess adhesive on the base of the needle during manufacturing to help prevent the base of the needle from becoming obstructed.
[0073] The above disclosure sets forth a number of embodiments of the present invention. Other arrangements or embodiments, not precisely set forth, could be practiced under the teachings of the present invention and as set forth in the following claims. | A device for collecting a blood sample from a plastic segment tube into a receptacle uses a cylindrical housing containing a hollow needle to puncture the segment tube as it is inserted into the upper port of the device. A series of ribs with medial edges are arranged in a radial pattern around the needle within the upper port to guide and support the segment tube as it is inserted. The ribs are separated by slots that also guide the sealed end of the segment tube. An annular recess around the lower port of the device holds the rim of the receptacle and allows blood released by the punctured segment tube to drain into the receptacle. The annular recess accommodates a wide range of test tube diameters, and exerts only a downward force on the rim of the receptacle when a segment tube is inserted into the upper port of the device. | 8 |
FIELD OF THE INVENTION
[0001] The invention relates to a tube to be used in a device for heating of a gas or liquid medium that is transmitted from one end of said tube to the other end thereof while simultaneously being heated such that a chemical reaction occurs. The heating can occur for instance by heating the exterior tube wall or by providing heating directly through the walls.
BACKGROUND OF THE INVENTION
[0002] In the description of the background of the present invention that follows reference is made to certain structures and methods, however, such references should not necessarily be construed as an admission that these structures and methods qualify as prior art under the applicable statutory provisions. Applicants reserve the right to demonstrate that any of the referenced subject matter does not constitute prior art with regard to the present invention.
[0003] In order to obtain an acceptable yield of a product, such as ethylene in an ethylene cracker, it is necessary to use a tube that is free from cracks on its inner side. The tube must also be resistant towards exposure of those products that are formed inside such tube. When using materials currently for such tube applications it frequently occurs that oxides are being formed on the inside of such tubes and that easily come apart therefrom, which reduces the lifetime of such tubes. At the same time there is a problem with carbonizing since a deposit of a carbon compound is formed on the inside of such tube. The larger deposit that is formed, the smaller is the amount of gas that can be passed through such tube. At the same time the heat transformation will decrease which results in an impaired economy.
[0004] Known furnaces for the cracking of hydrocarbon are usually provided with cast tubing of nickel-based alloys with high amounts of chromium. This leads to some disadvantages because such tube materials are more expensive and further, high nickel content can be a catalyst for undesirable coking.
[0005] Also, the ability of tubes made from such materials to maintain their original shape, which normally are characterized as high temperature materials, is not satisfactory in certain applications.
[0006] In a cracker, a decomposition of a hydrocarbon occurs. The starting materials could be for instance naphta or propane mixed with water vapor. When the material passes through the tubes in the cracking furnace the temperature is increased to above 800° C. Important products that are being obtained are for instance ethylene and propylene. Also hydrogen gas, methane, butane and other hydrocarbons are being formed. In order to avoid undesired reactions it is essential that such heating occurs very rapidly and that the obtained products are subjected to quenching—the residence time in the furnace only amounts to some tenths of seconds. The temperature in the furnace can reach 1100-1200° C.—and the tube material temperature in the furnace could be above 1100° C. The heating of the furnace room could be obtained by combustion of gases from the cracking process such as hydrogen and methane, and a furnace can be equipped with a large number of gas burners that can be arranged in the floor or in the walls such furnace.
[0007] The tubes that are used in the furnace shall have good shape permanence to heat and shall be able to withstand high temperatures. They must also be resistant towards oxidation and corrosion so as to withstand the atmosphere in the furnace room. The carbon potential inside the tubes in the furnace is very high and the tube material should therefor be able to withstand carburization and carbide formation. Minor amounts of sulphur are often being added to the starting material and therefor the tubes must also have good resistance towards sulphur and sulphur compounds.
SUMMARY OF THE INVENTION
[0008] The present invention relates to a new type of finned tube to be made of a material that improves resistance towards the environment in furnaces for the cracking of hydrocarbon external to the tube, as well as the particular environmental conditions occurring inside the tube.
[0009] According to one aspect, the present invention provides a metal tube for use in furnaces where gas and liquid formed media is being pressed through such tube from its inlet end to its opposite end while being subjected to substantial heating and decomposition therefrom, the metal tube comprising: a body; a smooth outer surface; and an inner surface with a profile; wherein the body is made of a stainless iron-nickel-chromium base alloy comprising, in weight-%: -max 0.08% C, 23-27% Cr, 33-37% Ni, 1.3-1.8% Mn, 1.2-2% Si, 0.08-0.25% N, 0.01-0.15% rare earth metals, and normal impurities; and the profile comprises a plurality of valleys or recesses, said valleys or recesses extending longitudinally along the tube, and having a smoothly curved bottom.
[0010] By forming a tube with a high strength stainless steel with good resistance towards oxide flaking and carbonizing, the chemical resistance, and the economy of such tubing and furnaces have been improved in a special way. This has brought about a tube having very good heat transfer properties combined with substantially improved resistance toward too quickly appearing carbonizing, carburization and oxide flaking due to the products produced during such transfer of materials within the tube.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0011] The objects and advantages of the invention will become apparent from the following detailed description of preferred embodiments thereof in connection with the accompanying drawings in which like numerals designate like elements and in which:
[0012] [0012]FIG. 1 shows a tube with a formation in accordance with the invention.
[0013] [0013]FIG. 2 shows a cross section of the tube of FIG. 1.
[0014] [0014]FIG. 3 shows the weight change during oxidation in air and 1000° C. as a function of the exposure time of said tubes.
[0015] [0015]FIG. 4 shows schematically how the carburizing profile was measured on rod shaped specimen for analyzing the carbide content.
[0016] [0016]FIG. 5 shows the measurement results for carburizing in terms of area function of carbides.
DETAILED DESCRIPTION OF THE INVENTION
[0017] In FIG. 1, a tube 10 is designated having an entry end portion through which a gas formed medium such as hydrocarbon and steam shall be urged towards the exit end portion while undergoing a chemical reaction.
[0018] In the embodiment as shown, the inner surface 11 of the tube 10 is provided with re-cesses 13 and ridges 14 of a sinusoidal shaped contour, while the outer surface 16 is substantially smooth or arcuate, see FIG. 2. The ridges 14 and the recesses 13 are provided with a rounded profile to avoid fatigue cracks.
[0019] In accordance with an alternative embodiment, the interiorly provided recesses 13 of the cylinder 10 can be helically provided in the longitudinal direction of said tube.
[0020] Alternatively, instead of being cylindrical in its entire length, said tube can be conically shaped from its inlet end to its outlet end.
[0021] It has been found that the shape permanence during heating of tubes according to the present invention can be improved if the tubes are made by pilger rolling over a mandrel in principle in the manner as shown and described in U.S. Pat. No. 4,095,447. Alternatively, however, such tubes could be made in the manner described in U.S. Pat. No. 5,016,460. Instead of pilger rolling over a mandrel drawing over a mandrel can be applicable.
[0022] The steel material to be selected for such cylinder 10 is a stainless iron-nickel-chromium base alloy with an austenitic structure and otherwise strictly controlled and optimized amounts of alloy constituents. The alloy contains, in weight-%, max 0.08% C, 23-27% Cr, 33-37% Ni, 1.3-1.8% Mn, 1.2-2% Si, 0.08-0.25% N, 0.01-0.15% rare earth metals and Fe and normal impurities. The amount of rare earth metals are preferably 0.03-0.10% which promotes the formation of a thin elastic adherent oxide film when the material is exposed to oxidizing environment at high temperatures. The amount of nitrogen should preferably be 0.13-0.18%, and the amount of silicon should preferably be 1.3-1.8%.
[0023] By the above given choice of material, it is possible to achieve unexpectedly superior, substantially longer, usage time periods without interruption for exchanging tubes while simultaneously also achieving a substantially smaller amount of deposits of carbon compounds on the inner tube side, which furthermore improves the usage economy since smaller amounts of deposits on the tubes enables larger amount of hydrocarbon and steam to be transported through the tubes, for instance in connection with the manu-facture of ethylene.
[0024] A further improvement can be achieved by providing a chromium oxide layer on the inner tube surfaces which will prevent the diffusion of carbon into the material by oxidation of said tubes before they are put into usage.
[0025] [0025]FIG. 3 illustrates the results of a study of the tendency toward oxide flaking in tubes made of Sanicro 39 type material according to the invention put in relation to some conventional materials that are being used in corresponding applications. For reference purposes this study included both forged and cast alloys which are well established materials for cracker tubes in ethylene furnaces, for instance a material marketed by International Nickel Inc. under the designation INCO 803, one material marketed by Sumitomo Metals Ltd under designation HK4M and a cast alloy with designation HP45-Nb. The analysis of the various reference materials is given in the table below.
Alloy Cr Ni Si Mn C N Nb Ti Al HP45-Nb 23.6 36.9 1.4 1.22 0.17 0.046 1.2 — — Inco 803 25.8 35.3 0.65 0.90 0.075 0.013 — 0.55 0.52 HK4M 25.3 24.5 0.41 1.12 0.21 0.017 — 0.46 0.33 Sanicro39 24.9 34.8 1.5 1.4 0.048 0.166 — — — REM = 0.05
[0026] The diagram in FIG. 3 shows the weight change during oxidation in air at 1000° C. as a function of the exposure time for the tubes.
[0027] As appears from the diagram in FIG. 3 the obtained result shows that the oxides being formed more easily come apart from these reference materials when compared with the material Sanicro 39 selected according to the invention.
[0028] The carburizing tests were carried out so as to be similar to the ethylene environment present in the aforementioned cracker applications by providing shifting carburizing and oxidizing environments. The carburizing occurred in a gas mixture comprising carbon monoxide, hydrogen gas and methane in a mixture which was at a temperature of 1050° C. and gave an oxygen potential corresponding to 10-15 atm and a carbon activity >1. After being exposed for 120 hours to this carbonizing environment the coke that had been formed was taken out by introducing air to combust the coke. The time period for the carburizing/oxidizing cycle varied between 135-140 hours. The total testing time was 1104 hours corresponding with 8 cycles as set forth above. The temperature was kept constant at 1050° C. during the entire first test. The geometry of the test rods was 8 mm×8 mm×20 mm.
[0029] After the test was completed the test rods were taken out and a cross section thereof was studied by looking upon how the area fraction of carbides varied along a selected line. The cross section of said test rods had a square shaped outer surface and with this test rod design it was found that the carbonizing was much depending on where on this outer surface the measurement was made. Areas close to corners and edges appeared to be more sensitive to carbonizing than those surfaces that were planar. In FIG. 4, it is shown the position of the lines that are analyzed in the cross section of the test rod. The first line (Prof 10) was located 0.8 mm (10% of the edge length) into the material along the outer surface. The second line (Prof 50) was located 4 mm from a corner whilst being extended through the center of the test rod. In FIG. 4 it is schematically shown how carburizing varies depending on whether the location is close to an edge or extending far into a planar surface.
[0030] This figure also schematically shows how the carburizing depth varies depending on the distance from a corner. The grey marked area represents the carburized area and the white field represents the noncarburized area. It should be noted that the carbonizing depth is larger in the corners of the test rod.
[0031] In FIG. 5 the results from the area fraction analysis of carbides are presented. The x-axis represents the distance from the start point at one outer surface (0-8 mm) and the y-axis shows the measured area fraction of carbides (%) The diagram shows that Sanicro 39 and HP45-Nb are not affected by carburizing from planar surfaces (Prof 50) and out of these two Sanicro 39 appeared with the best resistance towards carburizing in the area close to the corners or the edges (prof 10). The alloy 803 was affected by massive carburizing in the corner areas and also appeared with strong carburizing on the planar surfaces. The alloy HK4M was subjected to carburizing to its maximum through the entire material.
[0032] While the present invention has been described by reference to the above-mentioned embodiments, certain modifications and variations will be evident to those of ordinary skill in the art. Therefore, the present invention is limited only by the scope and spirit of the appended claims. | The invention provides a tube for use in furnaces where gas and liquid media are being passed through the tube from one end to the other while being subjected to substantial heating and decomposition resulting therefrom. The tube is made of a stainless iron-nickel-chromium-base alloy comprising in weight-% max 0.08% C, 23-27% Cr, 33-37% Ni, 1.3-1.8% Mn, 1.2-2% Si, 0.08-0.25% N, 0.01-0.15% rare earth metals, and Fe and usual impurities. The cylindrical tube has a smooth outer surface and an inner surface provided with valleys or recesses extending longitudinally with a smoothly curved bottom profile. | 2 |
RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application No. 61/737,947 filed Dec. 17, 2012.
FIELD OF THE INVENTION
This invention generally relates to a gas piston unitary upper receiver system for an automatic or semiautomatic firearm, particularly for use with a standard AR15/M16 lower receiver.
BACKGROUND OF THE INVENTION
Issues with the direct impingement operation system of the AR15/M16 rifle (and variants thereof) are well known. Many attempts have been made to replace the original direct impingement operation system with a gas piston system. Some proposals are retrofit systems, in which the original gas tube is replaced with a piston and cylinder for short stroke operation of the bolt. These systems typically use the existing buffer spring that extends into the butt stock. Other solutions have been proposed in which an entirely new rifle is designed to include operator controls similar to those familiar in the AR15/M16 platform. For example, Remington Arms has produced its Adaptive Combat Rifle (ACR) and FN Herstal (FNH USA) has proposed its MK16 and MK17 rifles, the latter of which was adopted by the United States Special Operations Command (SOCOM) as a result of the Special Operations Forces Combat Assault Rifle (SCAR) competition. Each of these examples includes a recoil spring within the upper receiver, allowing the butt stock to be folded, if desired. These designs, however, utilize a unique (nonstandard) lower receiver and require complete replacement of existing rifle systems, rather than allowing modification of existing weapons currently in inventory.
SUMMARY OF THE INVENTION
The present invention provides a number of features. It has a unitary upper receiver that mounts to any standard AR15/M16 lower receiver. The upper receiver, which houses a reciprocating bolt carrier assembly is unitary with a forearm portion which supports a barrel assembly, gas piston operation system, and charging handle. The gas operation system includes a long-stroke piston for positive operation of the bolt carrier assembly without introduction of dirty gases into the upper receiver and bolt carrier area. This allows the use of a non-reciprocating charging handle, which is fully ambidextrous and reduces the mass of reciprocating parts.
Unique geometry of the bolt carrier allows it to reciprocate on replaceable rails, which reduces the frictional contact area, can be provided with self-lubricating coatings, and allows axial alignment between the operation rod and recoil spring. According to one embodiment, a novel bolt is provided which allows it to be repositioned by the user for left- or right-handed (fully ambidextrous) operation. The unique geometry of the recoil spring and operation rod allows recoil forces of the reciprocating bolt carrier and piston rod assembly to be transferred to a robust portion of the upper receiver, rather than through a recoil spring and buffer housed in the butt stock of a typical AR15/M16 rifle platform, without tipping the bolt carrier.
The invention also provides a quick-change barrel assembly, held in place by a lower forearm cover, with a barrel trunnion that connects directly to the pivot pin of the lower receiver. The barrel assembly, comprising a barrel, barrel trunnion, gas block, gas regulator valve, and gas cylinder, can be easily removed and replaced as a unit. This allows quick change in barrel length, caliber, and twist rate, as desired by the user. Because the gas regulator valve and gas cylinder are part of the interchangeable barrel assembly, the gas control system may be matched to the characteristics of the barrel (caliber, and length, and twist rate) without any change to the gas piston, which remains connected to the bolt carrier assembly.
Because the recoil spring and buffer system is housed within the upper, it may be used with a folding stock in a rifle system or without any rearward protrusion in a pistol platform.
According to another feature of the invention, a clean-out port is provided in the gas block in axial alignment with the gas port and gas passageway in the barrel and gas block. When the gas regulator valve is removed, this allows direct access for cleaning these passageways without any other disassembly of the unit.
According to another feature of the invention, a two-stage recoil spring and buffer system may be used. This system provides rapid deceleration of the bolt carrier assembly during the final portion of rearward cycle.
According to another feature of the invention, a bolt having improved curvilinear lug geometry provides increased strength and resistance to cracking by minimizing or eliminating sharp edge cuts in the bolt face profile.
Other features, benefits, and combinations will be apparent from the various figures of the drawing and detailed description of preferred embodiments herein.
BRIEF DESCRIPTION OF THE DRAWINGS
Like reference numerals are used to indicate like parts throughout the various figures of the drawings, wherein:
FIG. 1 is a right side plan view of an upper assembly according to an embodiment of the invention shown mounted on a stripped lower receiver;
FIG. 2 is a view similar to FIG. 1 , showing the upper receiver body, lower receiver, and lower forearm cover cut-away in longitudinal cross-section;
FIG. 3 is an isometric rear-side view of the upper receiver assembly shown in FIG. 1 ;
FIG. 4 is a pictorial view similar to FIG. 3 in which the upper receiver body has been removed to expose the inner working parts of the device;
FIG. 5 is a fragmentary longitudinal sectional view of the gas block and gas regulator valve;
FIG. 6 is a cross-sectional view taken substantially along line 6 - 6 of FIG. 5 ;
FIG. 7 is a fragmentary pictorial view of the bolt carrier assembly;
FIG. 8 is a longitudinal sectional view taken substantially along line 8 - 8 of FIG. 7 ;
FIG. 9 is a view similar to FIG. 8 showing the firing pin retention gate lifted and the firing pin partially removed;
FIG. 10 is an exploded pictorial view of the bolt carrier assembly showing how the bolt is repositioned to change between left-handed and right-handed operation;
FIG. 11 is a plan view of the face of a prior art bolt;
FIG. 12 is an end plan view of a bolt face according to one embodiment of the present invention;
FIG. 13 is a cross-sectional view taken substantially along line 13 - 13 of FIG. 14 , but with the bolt carrier assembly shown in a retracted position;
FIG. 14 is a fragmentary pictorial view of a rear portion of the upper receiver assembly;
FIG. 15 is a fragmentary pictorial view of the other side thereof;
FIG. 16 is a partially exploded view similar to FIG. 14 ;
FIG. 17 is a partially exploded view similar to FIG. 15 , but with the interchangeable parts reversed for left-handed operation;
FIG. 18 is a fragmentary, partially cut-away top plan view of a forward portion of the charging handle body showing positions of the charging handle lever;
FIGS. 19-22 are a series of fragmentary partially cut-away views of a rear portion of the upper receiver assembly illustrating the steps involved in field stripping disassembly;
FIG. 23 is a fragmentary partially cut-away view of a forward portion of the receiver body and barrel assembly;
FIG. 24 is a disassembled view thereof;
FIG. 25 is a pictorial exploded view of the upper receiver body, barrel assembly, and lower forearm cover;
FIG. 26 is a view of the upper assembly showing a two-stage recoil spring system in a first, in battery position;
FIG. 27 is a view Like FIG. 26 showing the two-stage recoil spring system in a second, less-than-fully-retracted position;
FIG. 28 is a view Like FIGS. 26 and 27 showing the two-stage recoil spring system in a third, fully retracted position;
FIG. 29 is a graph illustrating the force curve of the two-stage recoil spring;
FIGS. 30 and 31 are isometric views of a bolt having a novel lug profile;
FIG. 32 is a longitudinal sectional view taken substantially along line 32 - 32 of FIG. 33 ; and
FIG. 33 is an enlarged end plan view of the bolt face profile.
DETAILED DESCRIPTION
Referring to the various figures of the drawing, and first to FIG. 1 , therein is shown a firearm having a gas piston operated unitary upper receiver assembly 12 mounted on a standard AR15/M16 lower receiver assembly. The lower receiver 14 may be that of a standard AR15/M16 rifle (or pistol). As used herein, the terms AR15, M16, M4, and other variants of these firearm platforms are used interchangeably. The present invention is operable in semiautomatic mode or may be operable in full automatic mode with appropriate modification. FIGS. 1-4 illustrate a lower receiver 14 without a fire control group (lower parts kit), butt stock, hand grip or magazine. A butt stock mountable to any standard AR platform variant can be attached at 16 , a hand grip at 18 , and a removable magazine inserted into a magazine well 20 . A wide variety of stocks, grips, and accessories are available to interface with the standard AR15 lower receiver 14 . Specifics of these parts are not important to the present invention, and for sake of simplicity, are not shown in the other figures. The upper receiver assembly 12 of the present invention is fully usable with a lower receiver 14 in a pistol configuration (not shown). The present invention also allows use of a folding stock (not shown), if desired, or continued operation after the butt stock has been bent or broken.
The upper receiver assembly 12 attaches to the lower receiver 14 using the standard takedown pin 22 and pivot pin 24 . By utilizing a standard AR15/M16 platform lower receiver 14 , existing weapons systems may be upgraded without replacement, particularly of the serialized lower receiver 14 , legally considered to be the “firearm.”
The upper receiver assembly 12 includes a unitary upper receiver body 26 which may be billet milled or otherwise formed of a suitable material, such as an aluminum alloy. Alternatively, an extrusion of a suitable profile may also be formed and milled to final specifications or could be molded from a suitable polymer material.
As shown in FIGS. 1 and 3 , an ejection port 28 is provided on one side, in this example, the right-hand side. An elongated charging handle opening 30 is provided on each side of the receiver body 26 to allow longitudinal movement of a laterally extending charging handle lever 32 . The charging handle lever 32 may be switchable without tools from either side to the other at the operator's discretion. The upper receiver body 26 includes a unitary fore end (forearm) and may include an integral top Picatinny (MIL-STD 1913) accessory mounting rail 34 . Additional accessory rails 36 , 38 may be provided at the 9 o'clock and 3 o'clock positions. A separate lower forearm cover 40 may also include a bottom accessory rail 42 . FIGS. 3 and 4 show the upper assembly 12 separate from the lower receiver assembly. Unlike a typical AR15 variant receiver having a rear charging handle, the upper receiver assembly 12 of the present invention is completely closed at its rear end, which is adjacent the operator's face when shooting, precluding any undesired escape of gases or combustion particles and providing enhanced strength.
Referring now to FIGS. 2 , 3 and 4 , therein can be seen a gas piston operating system according to the present invention. FIG. 2 is a side plan view showing the upper receiver assembly 12 and a stripped lower receiver 14 in longitudinal section. FIG. 4 shows an isometric view of the entire internal system, but with the upper receiver body 26 being shown cut away in cross-section. The trigger and hammer mechanism parts of the lower receiver 14 are not shown for sake of clarity and because they do not form any part of the present invention. The trigger assembly and selector switch for any standard semiautomatic or fully automatic AR variant will function with the present invention.
Referring now in particular to FIGS. 2 , 4 , 7 , 19 and 20 , the present invention provides a novel bolt carrier assembly 48 . The bolt carrier assembly 48 has a body 144 that is relatively square in cross-section rather than the typical round shape used in a direct impingement or gas piston conversion AR15/M16 variants. Also, rather than having a relatively large surface area of the bolt carrier in sliding contact within a generally tubular upper receiver, the present bolt carrier body 49 has lateral guide channels 54 , 56 which engage and slide along left and right guide rails 58 , 60 . In preferred form, the guide rails 58 , 60 are made of a hardened and wear-resistant material, such as steel, and may include a lubricious coating. These guide rails 58 , 60 are fixed into channels formed longitudinally inside the upper receiver body 26 and may be secured by a series of threaded fasteners 62 . The reciprocation track provided by these guide rails 58 , 60 is closely adjacent to and parallel with the axis of the gas piston system (to be described below) and is vertically situated between the gas-piston/recoil-spring axis and the bore axis of the barrel. This orientation produces less angular loading on the bolt carrier body 49 and other parts that reciprocate when the action is cycled.
Operation of the gas piston system can be seen by reference to FIGS. 2 , and 4 - 6 . The barrel 70 includes a gas port 72 . A gas block 74 is positioned on the barrel 70 and fastened such as by pinning. The gas block 74 includes a gas passageway 76 and houses an adjustable gas valve 78 . Referring now particularly to FIG. 6 , the gas valve 78 may be rotatably adjusted to provide a larger or smaller orifice, or may be positioned to completely close the gas passageway 76 for operation in a single shot mode. Accordingly, adjustment of the gas valve 78 allows the gas system to be “tuned” as required by variations in ammunition or use of a noise suppressor.
In autoloading mode, the gas valve 78 directs gas pressure from the bore of the barrel 70 into a gas tube or cylinder 80 , which is affixed to and extends rearwardly from the gas block 74 . A piston rod 82 , having a piston head 84 , is positioned within the cylinder 80 and is acted upon by gases ported from the barrel 70 through the gas block 74 and valve 78 . The piston rod 82 extends rearwardly to an integral operation rod (op rod) 86 , which is attached by threaded engagement to the forward bolt carrier lug 50 of the bolt carrier body 49 .
Referring now also generally to FIGS. 26-28 , when gas pressure bears upon the piston head 84 , the piston rod 82 and op rod 86 are shifted rearwardly in a long-stroke operation to cycle the bolt carrier assembly 48 against the force of the recoil spring 66 . The op rod 86 may be tubular, as shown, in order to reciprocate over the guide rod 68 and spring 66 . This tubular portion of the op rod 86 may also be skeletalized with holes in order to reduce weight. Unless the bolt carrier 49 is locked back in an open position, the recoil spring will return these parts to their forward, in-battery position ( FIGS. 2 , 4 and 26 ). As is apparent from the figures, the gas piston 82 , op rod 86 , recoil spring 66 , and its guide rod 68 are all axially aligned. The bolt carrier assembly 48 reciprocates along a parallel track on closely adjacent guide rails 58 , 60 which are situated between the bore axis of the barrel 70 (and bolt 44 ) and the axis of the piston 82 , op rod 86 , and recoil spring 66 . Thus, angular forces and any tendency for tipping of the bolt carrier assembly 48 are minimized.
Referring to FIGS. 5 and 6 , according to another feature of the invention, a cleaning port 96 may be provided in the gas block 74 in axial alignment with the gas passageway 76 and gas port 72 . When the adjustable gas valve 78 is removed, this allows cleaning access to the gas passageway 76 and gas port 72 without any other disassembly being required.
The barrel assembly 110 includes the barrel 70 , barrel trunnion 98 , gas block 74 , gas pressure control valve 78 , and gas cylinder 80 . The bolt carrier assembly 48 includes a bolt carrier body 49 , a forwardly-extending tubular op rod 86 , gas piston 82 , bolt 44 , and firing pin 46 . The recoil buffer assembly 112 includes a removable buffer block 114 , a rear closure plate 116 , a guide rod 154 , and recoil spring 156 .
The action may be manually cycled by pulling the charging handle lever 32 (shown in a forwardly folded position in FIGS. 3 , 4 , and 6 ) rearwardly to slide the charging handle body 88 . The charging handle body 88 includes forward and rearward laterally-extending guide ribs 92 which travel in longitudinal guide grooves 94 formed in the upper interior portion of the receiver body 26 . The charging handle body 80 also includes a downwardly-extending lug 90 which provides a one-way engagement with the forward end of the op rod 86 . In preferred form, the charging handle body 88 and charging handle lever 32 do not reciprocate as the gas piston system cycles, but may be used to manually cycle the action against the recoil spring 66 . As shown in FIGS. 1 , and 3 , the charging handle body 88 includes a pair of laterally extending guide ribs 92 which slide along guide grooves 94 formed longitudinally on the inside of the upper receiver body 26 . The charging handle body 88 is elongated in order to completely close the charging handle openings 30 when in its forwardmost position. According to another feature of the invention, explained in further detail below, the charging handle lever 32 may be easily switched by the user from the left side to the right side through either charging handle opening 30 . The charging handle body 88 may be disassembled from the upper receiver body 26 by removing the charging handle lever 32 and aligning the ribs 92 with downward openings (not shown) in the guide grooves 94 at a rearward position beyond that normally encountered by manually cycling the action.
Manual rearward cycling of the charging handle body 88 displaces the bolt carrier assembly 48 (via op rod 86 ) rearwardly, compressing the recoil spring 66 . As shown in this embodiment, a charging handle return spring 118 , carried by a guide rod 120 , may be included to bias the charging handle body 88 back toward a forward position, even when the bolt carrier assembly 48 is locked in an open, rearward position ( FIG. 28 ). As in the previously-described embodiment, the receiver body 26 may include both left and right charging handle openings 30 in order to allow the charging handle lever 32 to be switched between left-handed and right-handed operation orientation. The charging handle body 88 completely covers and closes both charging handle openings 30 when it is in its normal forward position. In this embodiment, the charging handle body 88 includes a central opening or bore 122 which receives the guide rod 120 when the charging handle body 160 is manually reciprocated rearwardly.
Referring now to FIGS. 1 , 3 , and 6 , according to another feature of this embodiment, the receiver body 26 may include removable left and right accessory mounting rails 36 , 38 corresponding to the three o'clock and nine o'clock positions. The rails 36 , 38 may be attached with threaded fasteners 124 and may include a heat shield or insulating shim 126 (shown in FIG. 6 ) to reduce heat transfer between the receiver body 26 and accessory mounting rails 36 , 38 . If desired, the bottom rail 42 on the lower forearm cover 40 may be made as a separate piece and attached in a similar manner. Alternatively, the accessory rails 36 , 38 , 42 , may be made of a non-metallic, polymer material that is a poor thermal conductor to reduce heat transfer.
Referring now to FIGS. 5 and 6 , therein is shown longitudinal- and cross-sectional detail views of the gas block 74 and gas valve 78 . The gas block 74 includes a multi-position gas valve 78 which is rotationally adjustable and removable. The gas valve body 78 may be retained in any of the selected positions by an internal spring detent (not shown). When the gas adjustment control valve body 78 is removed, there is direct and axially-aligned access to the gas cylinder 80 for cleaning and maintenance. Also as described with respect to the previous embodiment, the gas block 74 may include a cleaning port 96 which is axially aligned with the gas port 72 of the barrel 70 and gas passageway 76 . This feature allows direct access to these passageways which may become fouled and are otherwise difficult to physically clean.
As shown in FIG. 7 , the bolt carrier assembly 48 includes a bolt carrier body 49 with an upwardly-extending forward bolt carrier lug 50 to which the tubular op rod 86 is attached. The bolt carrier body 49 includes upper left and right guide channels 54 , 56 which slidingly engage longitudinal guide rails 58 , 60 along the interior of the receiver body 26 (see FIGS. 13 , 21 and 22 ). The guide rails 58 , 60 may be made of a hardened and wear-resistant material, such as steel, and may include a lubricious coating. If desired, exterior portions of the bolt carrier body 49 , particularly the guide channels 54 , 56 , may also be provided with a lubricious coating.
In the illustrated embodiment, the right guide channel 56 extends along a substantial portion of the overall length of the bolt carrier body 49 . The left guide channel 54 is interrupted between forward and rearward sections to allow for other mechanical structure and operations of the bolt carrier assembly 48 . These bolt carrier guide channels 54 , 56 are positioned vertically between a longitudinal axis of the gas piston 82 , op rod 86 , forward bolt carrier lug 50 , and recoil spring 66 and the vertical axis of the barrel 70 and bolt 44 . Accordingly, recoil forces acting on the bolt carrier assembly 48 as it cycles resist tipping, which could cause uneven and undesirable wear and friction.
Referring now also to FIGS. 8 and 9 , therein is shown another feature of the present invention. Removal of the firing pin 46 is made easy by a vertically displaceable firing pin retention gate 128 that is retained by and slides in opposite vertical channels 130 provided in the bolt carrier body 144 . The retention gate 128 is actuated by a lift lever 132 which is mounted on a pivot pin 134 extending between the left and right guide channels 54 , 56 . The lift lever 132 includes a tooth 136 that pivotally engages a window or socket 138 in the firing pin retention gate 128 . The lift lever 132 may be biased by a spring 140 into a closed position, as shown in FIG. 8 . As shown in FIG. 9 , when the lift lever 132 is pivoted (arrow 142 ), the tooth 136 is moved to lift (arrow 144 ) the firing pin retention gate 128 to a position allowing the firing pin 46 to be slid rearwardly out of the bolt 44 . This feature of the invention allows field removal of the firing pin 46 for disassembly of the bolt carrier 48 without risk of losing a small retainer pin, as used in the prior art.
According to another aspect of the invention, the upper receiver assembly 12 can easily be manufactured and set up to eject spent casings to either the right or left side. Moreover, it can be made to be easily convertible by the user to operate in either a left-hand or right-hand mode. As previously described, the charging handle lever 32 is easily switchable from side to side. Additionally, a novel bolt design allows the user to selectively choose whether it is configured to eject spent casings toward the left or toward the right.
Referring first to FIG. 10 , therein is illustrated how the bolt 44 is easily removed in a forward direction from the bolt carrier body 49 . The firing pin 46 (not shown in FIG. 10 ) is removed longitudinally, followed by removal of the bolt cam pin 146 , which allows the bolt 44 to be slid forwardly out of the bolt carrier body 49 . The bolt 44 can then simply be axially rotated 180° and reassembled into the bolt carrier body 49 with the bolt cam pin 146 and firing pin 46 .
As shown in FIGS. 11 and 12 , the geometry of the bolt head and face may differ significantly from the standard prior art bolt used in an AR15/M16 platform firearm. In the prior art bolt head 148 , the extractor 150 and ejector 152 are positioned to eject a spent casing at approximately a 2 o'clock position (as viewed from the rear). The prior art bolt head 148 includes 8 radially-extending lugs, including one 154 carried by the extractor 150 . The bolt head 156 of the present invention also includes eight lugs 158 in a geometric orientation similar to that of the prior art bolt head 148 . However, the extractor 160 is positioned between lugs 158 . Thus, the extractor 160 and ejector 162 may be positioned at substantially horizontally opposed locations. Referring now again to FIG. 10 , when the bolt is oriented as shown at 44 a , the extractor 160 and ejector 162 are oriented to eject toward the right (or three o'clock position). When the bolt is rotated to the orientation shown at 44 b , the extractor 160 and ejector 162 are reversed and it is oriented to eject a casing toward the left (or nine o'clock position). In either orientation, the bolt cam opening 164 is properly oriented to receive the bolt cam pin 146 . This is in contrast with the geometry of a prior art bolt head 148 ( FIG. 11 ) which, if reversed, would eject a casing toward an eight o'clock position (as viewed from the rear). Thus, an ejection port is provided in the receiver body 128 at either the right 28 a or left 28 b , or both (see FIGS. 13 , 16 and 17 ). Either or both ejection ports 28 a , 28 b are closed and covered by the lateral wall portions of the bolt carrier body 49 when in a closed, fully in-battery position. Accordingly, the same bolt 44 of the present invention can be repositioned, including by the user with simple field disassembly, to operate in either a left-handed or right-handed configuration.
According to another aspect of the present invention, the upper receiver body 26 can be provided with both right and left ejector ports 28 a , 28 b that are reconfigurable, along with the bolt 44 , to select between right-handed or left-handed ejection. Referring now to FIG. 13 , therein is shown is a rearwardly looking cross-sectional view through the upper receiver assembly 12 with the bolt carrier assembly 48 in an open or retracted position. This view illustrates the manner in which the upper receiver body 26 may be provided with both right and left ejector ports 28 a , 28 b , making the upper receiver assembly 12 fully ambidextrous and easily converted in the field from right-to left-handed operation. As shown in FIG. 13 , the bolt 44 is positioned such that the extractor 160 is positioned toward the right to provide ejection of spent casings through the right ejection port 28 a . If desired, the left ejector port 28 b may be closed with an ejection port cover 166 .
Referring now also to FIGS. 14-17 , it can be seen that a shell deflector 168 may be provided rearwardly adjacent the open ejection port 226 to prevent ejected casings from exiting the port 28 a at an angle more rearwardly than desired. Both the ejection port cover 166 and shell deflector 168 are secured to the upper receiver body 26 by a pair of interchangeable threaded fasteners 170 . In this manner, after the bolt 44 has been positioned, as described above, for left- or right-handed ejection, the ejector port cover 166 and shell deflector 168 are accordingly positioned on the receiver body 26 adjacent the respective ejector ports 28 a , 28 b.
Referring now to FIG. 18 , therein is shown a partially cut-away detail top plan view of the engagement between the charging handle lever 32 and charging handle body 88 . A transverse window 172 is provided through a forward portion of the charging handle body 88 . A retainer pin 174 extends vertically through the transverse window 172 , secured to upper and lower portions of the charging handle body 88 . Axially rearward of the retainer pin 174 is a forwardly-directed spring-biased detent pin 176 . At the attachment end of the charging handle lever 32 , there is a partially open engagement bight 178 which is positioned to engage the retainer pin 174 . Against the spring bias of the detent pin 176 , the charging handle lever 32 can be pivotally positioned to a forward, folded position or a rearward, use position. When in the in-use position, an abutment surface 178 of the lever 32 bears against the charging handle body 88 and provides a fulcrum against which force can be applied to rearwardly cycle the charging handle body 88 . When the charging handle lever 32 is pivoted to the forward, folded position, it remains retained against the retainer pin 174 by the spring-biased detent pin 176 . To remove the charging handle lever, it can be manipulated rearwardly against the detent pin 176 without pivoting about the retainer pin 174 . In this manner, the bight 178 is disengaged from the retainer pin 174 and may be laterally removed from the transverse window 172 . The charging handle lever 32 may then be inverted and inserted from the opposite side of the transverse window 172 for pivotal engagement with the retainer pin 174 on the opposite side.
As described above with reference to FIGS. 10-18 , it can be seen that the upper receiver assembly 12 of the present invention can be fully ambidextrous and easily switched with few or no tools from right-handed to left-handed operation. The left or right position of the charging handle lever 32 can be chosen independently of the ejection direction of the bolt 44 .
Referring now FIGS. 19-22 , therein is shown a series of views illustrating the process of field disassembly or field stripping of the upper receiver assembly of this embodiment of the present invention. These figures show a side plan view of a rear portion of the upper receiver assembly 12 with the upper receiver body 26 and lower forearm cover 40 cut away in longitudinal section. For clarity of illustration, the recoil spring 66 and charging handle return spring 118 are not shown in their full length in these figures. In the case of the recoil spring 66 , it should be understood that the spring extends into the hollow op rod 86 . It is also to be understood that field stripping can be accomplished while the upper receiver assembly 12 is attached to a lower receiver 14 and tipped open on the forward pivot pin 24 or while the upper assembly 12 is completely separated from the lower receiver 14 .
Referring first to FIG. 19 , therein is shown at 180 a fixed portion of the recoil buffer. While the receiver body 26 is preferably milled from a lightweight aluminum alloy, the buffer fixed portion 180 is preferably made of a harder material, such as steel. The fixed portion 180 may be configured to fit in engagement slot (not shown) formed within the receiver body 26 and either permanently fixed or rigidly fixed, such as by a set screw 182 . The buffer fixed portion 180 includes a downwardly and forwardly directed tooth 186 configured to engage in a mating tooth 188 of a removable portion 184 of the recoil buffer system. The buffer removable portion 184 is secured to the rear closure plate 116 and recoil spring guide rod 68 . When the upper receiver assembly 12 has been either tilted open on pivot pin 24 or separated from the lower receiver 14 (as shown in FIGS. 19-22 ), the recoil spring and buffer system may be removed from the receiver body 26 by applying forward force (arrow 194 ) against the rear cover plate 116 and against the force of the recoil spring 66 , which otherwise retains the removable portion 184 of the buffer engaged against the fixed portion 180 . If desired, the buffer system may be further secured against inadvertent displacement by use of a small but strong magnet 190 (such as a 0.25 inch diameter×0.10 inch thick rare earth magnet) set into a recess 192 in the buffer fixed portion 180 . Optionally, a locking mechanism in the form of a captured cross pin 200 , similar in design to a take-down pin 22 or pivot pin 24 may be provided on the upper receiver body 26 and extend through a transverse opening 202 in the rear closure plate 116 to prevent inadvertent dislodgement of the removable buffer block 184 .
As shown in FIG. 20 , once the respective teeth 186 , 188 of the fixed and removable portions 180 , 184 of the buffer have been disengaged from each other by the forward movement (arrow 194 ) and a slight downward movement (arrow 196 ), the entire recoil buffer assembly, including removable buffer portion 184 , rear cover plate 116 , guide rod 68 , and recoil spring 66 may be rearwardly pulled (arrow 198 ) from the receiver body 26 .
As shown in FIG. 21 , the bolt carrier assembly is now free to slide rearwardly along guide rails 58 , 60 . In this manner, the entire bolt carrier assembly, including the bolt carrier body 49 , bolt 44 , firing pin 46 , op rod 86 , and piston 82 , easily slides rearwardly out the back of the receiver body 26 .
Referring now to FIGS. 23-25 , therein is shown the manner in which the barrel assembly 110 may be securely attached to the upper receiver body 26 and quickly detachable therefrom for exchange. The barrel assembly 110 includes a barrel trunnion 98 with a downwardly-extending lug 100 by which the trunnion 98 is directly secured to the forward pivot pin 24 of a standard lower receiver 14 . The barrel trunnion 98 includes a pair of laterally opposed, longitudinally extending engagement rails (or keys) 102 , 104 which are configured to slidingly engage a rear pair of engagement grooves (or keyways) 106 , 108 formed inside the receiver body 26 .
The gas block 74 also includes a pair of laterally opposed, longitudinally extending engagement rails 204 which are configured to slidingly engage a pair of forward engagement grooves 206 formed on the interior of the upper receiver body 26 .
Referring also again to FIG. 6 , therein it can be seen that the relative exterior dimensions of the gas block 74 and interior dimensions of the upper receiver body 26 may be configured such that there is a minute gap between these members around most of the periphery of the gas block 74 , with engagement being predominantly or exclusively between the engagement rails 204 and engagement grooves 206 . In this manner, heat transfer between the gas block 74 and receiver body 26 (and lower forearm cover 40 ) is minimized. If desired, an upper engagement key or rail 208 may be provided on the gas block 74 and an upper engagement groove or keyway 210 provided at the forward end of the upper receiver body 128 to provide additional engagement stability.
Referring particularly now FIG. 25 , the lower forearm cover 40 may be secured to the upper receiver body 26 with captive threaded fasteners 112 . When the forearm cover 40 is secured in place, the barrel trunnion 98 is held in place by longitudinal engagement of the trunnion rails 102 , 104 and rear engagement grooves 106 , 108 and against longitudinal displacement by the lower forearm cover 40 . As in the previously-described embodiment, the barrel assembly 110 is firmly secured against lateral or vertical movement within the unitary upper receiver body 26 . If desired, the dimensions of a lower portion of the gas block 74 may be machined oversized (i.e., “proud”) in the range of 0.004 inches to 0.007 inches in order to assure that the lower forearm cover 40 holds it tightly in place. Although the barrel trunnion 98 is firmly secured against longitudinal displacement, the remainder of the barrel assembly 110 may freely expand and contract in the longitudinal direction as a result of thermal changes independent of the upper receiver body 26 .
Referring now to FIG. 26 , therein is shown a two-stage recoil spring and buffer system. A first, main recoil spring 212 is positioned on the guide rod 154 and extends into the hollow op rod 86 , much like that previously described with respect to other embodiments herein. A secondary buffer spring 214 , which is relatively significantly shorter and heavier, is situated forward of and axially aligned with the main recoil spring 212 . Between the springs 212 , 214 is a block 216 which may act as a connector.
Referring now also to FIGS. 27 and 28 , it can be seen that, as the bolt carrier assembly 48 is driven rearwardly, either by force of gas pressure acting on the piston 82 (as shown) or manually retracted with the charging handle, the block 216 comes into contact with the end of the guide rod 68 . This limits and prevents further compression of the main recoil spring 212 , forcing further movement to compress the secondary recoil spring 214 . This final travel is limited to the very last portion of the recoil stroke, which may be no more than about 0.25 inches. Because the secondary recoil spring 214 is significantly stiffer than the main recoil spring 212 , a significant amount of recoil force is adsorbed in the final portion of travel and the velocity of the recoiling bolt carrier assembly 48 is quickly and significantly decelerated prior to impact contact between the forward lug 50 and the removable buffer block 184 . The heavier secondary spring 214 acts as a buffer, minimizing the impact of the bolt carrier assembly 48 against the lower buffer block 184 .
This rapid adsorption of force is illustrated graphically in FIG. 29 . At 0 (zero) position of the stroke, the bolt carrier assembly 48 is in battery, where the main recoil spring 212 is exerting about 4 pounds of force. As the action cycles rearwardly along the stroke curve, the force of the primary recoil spring 212 climbs until the block 216 contacts the end of the guide rod 68 and prevents any further compression of the primary spring 212 . The stroke curve (spring resistance force) climbs steeply in the final portion of the stroke. The deceleration (negative acceleration) of the bolt carrier assembly would be represented by a curve (not shown) substantially inverse of the force curve illustrated, with a significant portion of the deceleration occurring in a relatively small and final portion of the stroke cycle.
Referring now to FIGS. 30-33 , therein is shown at 218 a bolt according to another aspect of the invention in which the profile of the bolt lugs has an improved geometry. In most respects, the bolt 218 is the same in function and operation as that described above (at 44 ). It includes a bolt body 220 having a central longitudinal bore 222 for receiving the firing pin (not shown), a transverse bolt cam opening 224 , a spring-biased pivoting extractor 226 , and spring-biased ejector 228 . As described above with respect to the second embodiment, the illustrated bolt 218 has an extractor/ejector orientation that allows it to be reversed for left- or right-handed ejection of spent cartridge casings. This includes that the extractor 226 is oriented circumferentially between bolt lugs 230 , rather than carrying a lug as is the case in a prior art AR15/M16 bolt (see FIG. 11 ). The improved bolt lug geometry described herein may be incorporated successfully into either style of bolt.
Referring now in particular to FIG. 33 , it can be seen that the peripheral profile of the bolt face formed by the lugs 230 is a generally continuous curvilinear shape, rather than the angular, generally radial and circumferential shape of the prior art bolt 148 (see FIG. 11 ) or reversible bolt 146 ( FIG. 12 ) described above. The outer ends of each lug are rounded to eliminate a sharp longitudinal edge. The spaces between lugs are likewise rounded as troughs at the base of each adjacent lug, eliminating a sharp cut at the base of each lug. Although this profile narrows the width of each lug at the outer end 232 , the amount of material at the base 234 where the lug joins the body of the bolt face is increased by 20-30%. Moreover, the elimination of sharp cuts at these locations greatly enhances the structural integrity of the bolt face and lugs 230 to resist shear forces and reduces stress points where cracking in hardened materials is most likely to originate and occur. An outline of one prior art lug profile is shown for comparison in phantom line at 236 in FIG. 33 . The overall width (shown at 238 ) of the lug 230 is maintained to be substantially that of the prior art lug 236 . The curvature of the outer end 232 may have a radius (shown at 240 ) substantially half the width (shown at 238 ) of the lug 230 . Likewise, the overall depth (shown at 242 ) of each lug 230 is maintained to be substantially that of the prior art lug 236 . The curved profile of the space between adjacent lugs 230 may have a radius (shown at 244 ) that is substantially half the circumferential distance between the lugs 230 such that the smoothest possible curvilinear transition is provided to the profile.
Many features have been listed with particular configurations, options, and embodiments. Any one or more of the features described may be added to or combined with any of the other embodiments or other standard devices to create alternate combinations and embodiments. Although the examples given include many specificities, they are intended as illustrative of only one possible embodiment of the invention. Other embodiments and modifications will, undoubtedly, occur to those skilled in the art. Thus, the examples given should only be interpreted as illustrations of some of the preferred embodiments of the invention, and the full scope of the invention should be determined by the appended claims and their legal equivalents. | Disclosed is an upper receiver assembly for use with an AR15-type lower receiver. The upper receiver assembly includes a monolithic upper receiver and forearm housing. A barrel has a breech end, a muzzle end, a bore axis, and a barrel trunnion at the breech end having a lug for direct connection to the lower receiver using the pivot pin. It includes a bolt carrier assembly, having a longitudinal slot and rail engagement with the upper receiver housing on which the bolt carrier assembly slidably reciprocates, and a long-stroke gas-piston actuation system. A recoil spring assembly is housed within the monolithic upper receiver and forearm housing and extends coaxially with the longitudinal axis of the gas-piston actuation assembly. The barrel trunnion and gas block are configured for engagement with the upper receiver and forearm housing with longitudinal keyway features. | 5 |
This invention was made with Government support under Contract No. DAAH01-86-C-1131 awarded by the Department of the Army. The Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to missiles, and more specifically to programmable microcontrollers within missiles for controlling missile flight.
2. Discussion
The preferred embodiment of the present invention relates to the Tube-launched Optically tracked, Wire command link guided missile, more frequently referred to by the acronym TOW. The TOW missile is primarily an anti-tank weapon, having a maximum range of approximately 3,750 meters. This missile is capable of employment from a ground tripod, a military ground vehicle, or a military helicopter.
Operation of the TOW weapon system normally requires a two-man crew. After positioning the launcher, the operator looks through a combination day or night optical site to align the launcher with the path to the target. The operator then engages the firing mechanism.
During the flight phase, the missile emits two infrared signals which are received by two separate sensors on the launcher site. A missile guidance unit electronically coupled to the site and the launcher calculates missile position information and sends frequency modulated steering corrective signals to the missile through a wire link. The missile electronics unit receives the pitch and yaw correction signals and combines them with roll and yaw error signals from gyros within the missile to generate commands for positioning the missile control surfaces which, in turn, control the direction of the missile. The guidance process above repeats itself until the missile engages with the target.
The prior TOW missile electronics unit utilized hardware components to accomplish discrimination of frequency modulated pitch and yaw steering correction signals from the guidance unit, noise filtering of discriminated correction signals, system loop filter stability compensation, gyro loop compensation and self-balance loop stability. These hardware components added weight, size, and cost to the missile.
SUMMARY OF THE INVENTION
In accordance with the teachings of the present invention, an apparatus for controlling an airborne vehicle, such as a missile, is provided. The apparatus includes a guidance unit, remotely located from the airborne vehicle, which generates frequency modulated steering and control signals. A signal conditioning circuit, within the vehicle, conditions the steering and control signals. An attitude position sensing circuit, within the vehicle, senses and generates attitude position information. A programmable microcontroller, within the vehicle, receives the steering and control signals from the signal conditioning circuit and vehicle attitude position information from the attitude position sensing circuit, and generates flight commands for generating flight commands for controlling the flight of the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings, in which:
FIG. 1 is a perspective view showing the basic components of the TOW missile system;
FIG. 2 is a block diagram of the missile electronics unit, including the microcontroller; and
FIG. 3 is a flowchart of the basic functions of the microcontroller.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The basic operation of the TOW weapon system 10 is illustrated in FIG. 1. The launcher 12 is aligned with the target 16 using optical site 14. The site 14 has a day setting and a night setting. With site 14 maintained on the target 16, the firing mechanism is engaged thereby launching the missile 18. During its flight, the missile 18 sends back two modulated infrared signals 24 and 25 having different frequencies from infrared beacons 22 and 23 which are received by two separate infrared sensors 26 and 27 on the launcher site 14. Infrared beacon 22 emits signal 24, which is suitable for daytime and clear weather conditions. Infrared beacon 23 is suitable for night and cloudy, hazy or smoky conditions. Together, beacons 22 and 23 ensure that the missile guidance unit 28 receives a constant stream of information from the missile 18. The missile guidance unit 28 calculates missile position information from the modulated infrared beam 24 or 25 and generates corrective steering signals to put the missile 18 back on a path to the target 16.
An additional feature of the missile 18 is the shutter 96 on the beacon 23. The missile guidance unit 28 generates control signals for opening and closing the shutter 96, which are transmitted over the wires 30 to the missile 18. The opening and closing of the shutter 96 differentiates the beacon 23 from other emitting or "hot" sources along the missile's path.
The corrective steering signals sent from the missile guidance unit 28 are transmitted over the two wires 30 to an electronics unit 36 at the rear of the missile 18. The missile electronics unit 36 couples internally generated attitude position information from its gyros with the corrective steering signals from the guidance unit 28 and generates command signals for actuating the missile flight control surfaces 34.
The steering signals generated by the guidance unit 28 contain pitch and yaw information. Pitch angles are generally measured relative to a horizontal axis through the missile 18 and yaw angles are measured relative to a vertical axis through the missile 18. The control surfaces 34 increase and decrease the pitch and yaw angles in cyclic fashion. The time spent increasing pitch and yaw angles relative to the time spent decreasing pitch and yaw angles determines whether the missile goes up or down, turns left or right.
The guidance unit 28 generates a continuously variable amplitude carrier (CVAC) signal for the pitch and yaw control surfaces 34, which determines the time spent increasing pitch and yaw angles relative to the time spent decreasing pitch and yaw angles. The CVAC signal is a sinewave in which the positive amplitude portion represents an increase in the angle of the control surfaces 34, and the negative portion represents a decrease in the angle of the control surfaces. Moving the sinewave axis up or down determines the ratio of time spent increasing control surface angles to decreasing control surface angles. The point on the sinewave through which the axis cuts is the "zero-crossing" point. The pitch and yaw CVAC signals are frequency modulated by the guidance unit 28 and discriminated (reconstructed) by the electronics unit 36.
In FIG. 2 a block diagram of the electronics unit 36 is shown. On the lower left side of the diagram is the attitude position sensing circuit 56. Within the missile 18, the yaw gyro 58 and a roll gyro 60 generate attitude position information to be used by the microcontroller 70. The signals from the gyros are smoothed and amplified by the buffer circuits 62 and 64.
Frequency modulated signals from the guidance unit 28 enter the electronics unit 36 on the left side of the diagram at the input 40 of conditioning circuit 38. The primary purpose of the conditioning circuit 38 is to divide the transmitted signal into four different intelligence signals. Higher frequency pitch and yaw steering signals are separated from lower frequency control signals by capacitor 42 and low pass filter 44. Steering signals are separated into frequency modulated pitch and yaw signals by the steering separation filter 46. The pitch and yaw steering signals are then amplitude limited by the pitch squaring circuit 48 and the yaw squaring circuit 50, respectively. After passing through the low pass filter 44, the control signals are separated into a shutter open or close signal, for opening or closing the shutter 96 of beacon 23, and a yaw disable signal. The latter is sent by the guidance unit 28 to disconnect yaw gyro position information from the microcontroller 70 as soon as the missile 18 has stabilized after launch, the yaw gyro position information being no longer required to steer the missile 18. Positive threshold detector circuit 52 is used to sense a shutter open or close signal and negative threshold voltage detector circuit 54 is used to detect a yaw disable signal.
The microcontroller 70 operates in two stages, before (pre-fire) and after (fire) first motion of the missile 18. During an approximate 1.5 second period (pre-fire) after the firing mechanism is triggered, but prior to first motion, the missile 18 goes through a self-balancing routine. During this time, the pitch and yaw steering filters 72 and 74 are decoupled from the discriminators 66 and 68. Pitch and yaw self-balance filters 86 and 88 are coupled to the discriminators 66 and 68 by a software coupling means which is controlled by a wire 31 between the missile 18 and the launcher 12, the wire 31 being part of a circuit that is grounded at the launcher 12 before launch. The self-balance filters 86 and 88 are much like the steering filters 72 and 74 except the self-balance filters 86 and 88 are optimized for precise calibration of the launcher oscillators to the missile oscillator.
The launcher timing sequence causes the guidance unit 28 to transmit an unmodulated, constant frequency signal through the wires 30 and into the missile electronics unit 36. Since the signal is unmodulated, the output of the pitch and yaw discriminators 66 and 68 are converted to digital code representing constant voltages, ideally zero volts. The self-balance filters 86 and 88 filter the digital code using bilinear transform techniques, and then send the filtered codes on to the digital-to-analog converters 90 and 92 where they are converted back into analog voltages and sent to a voltage comparison circuit within the guidance unit 28. This feedback process repeats itself until the voltage received by the guidance unit 28 corresponds to the voltage transmitted.
After first motion and throughout flight, frequency modulated pitch and yaw signals from the guidance unit 28 are discriminated by discriminators 66 and 68. In more detail, during flight, the discriminators 66 and 68 reconstruct the CVAC signal from the steering signals generated by the guidance unit 28. Specifically, the guidance unit 28 frequency modulates the CVAC signal and the missile discriminators 66 and 68 demodulate the steering signals back into the CVAC signal. It is the microcontroller software that actually performs the demodulation process. The software program calculates the precise period of the carrier frequency and converts each period to a specific digital number. Each number represents a specific point on the CVAC sinusoidal function. The output signal of the discriminators 66 and 68 is a sinusoidal function of frequency, the positive amplitude side of the discriminated pitch signal representing a higher frequency or pitch angle increase signal and the negative amplitude side representing a lower frequency or pitch angle decrease signal. The operation of the yaw discriminator 68 is similar. Unlike the prior electronics unit, the present invention uses microcontroller software for the discriminators 66 and 68. The microcontroller uses a crystal oscillator thereby virtually eliminating missile drift error due to reference frequency shift during flight.
The digitally discriminated pitch and yaw signals are smoothed by the pitch and yaw steering filters 72 and 74. These filters use software employing bilinear transform techniques to filter the noise caused by discrimination digitizing of these signals. The pitch steering filter 72 and the yaw steering filter 74 complete the reconstruction of the CVAC signal in digital form.
The yaw and roll error signals from the attitude position sensing circuit 56 enter the microcontroller 70 and are converted to digital signals by analog-to-digital converters 80 and 82. Unlike the prior electronics unit, the present invention uses microcontroller software rather than "selected" hardware components to calibrate the yaw/roll error signals. The digital roll signal enters the logic unit 76 for processing by the software. As mentioned previously, the yaw error signal is normally inhibited during flight by the yaw decoupler 84 since yaw error signals from the yaw gyro 58 are only needed during early launch when the flight of the missile is most unstable. Shortly after launch, the missile guidance unit 28 sends a yaw disable signal, having a direct voltage level, into the microcontroller 70 where it sets a yaw disable flag.
After the yaw disable voltage level is set, the guidance unit 28 sends a shutter open or close signal, having a direct voltage level, which enters the microcontroller 70 and is processed by the logic unit 76. The software determines whether or not the shutter 96 of the infrared beacon 23 is open or closed. It also generates a pulse used by the driver 97 to open or close the shutter 96.
The microcontroller 70 uses software to generate the missile control actuator commands used by the drivers 94 to position the control surfaces 34. The advantages of this approach are that it results in a significant reduction in size and cost. There is no need to "select" hardware components to achieve the required system accuracy because the software contains built-in self-calibration routines. The microcontroller 70 executes several software routines in response to transitory signals called interrupts. The software is stored in the memory 78 and is advantageously capable of being changed independently of the launcher 12.
The method for controlling the missile 18 is illustrated by the software flow diagram in FIG. 3. The first step is to execute the initialization routine. The initialization routine is executed by the software when the microcontroller 70 receives a reset interrupt. The reset interrupt is generated by applying power to the missile 18. The initialization routine disables all other interrupts, initializes input and output hardware, and initializes software. After these jobs are complete, the initialization routine re-enables all interrupts, calibrates the outputs from the gyros, and enters a main idle loop to await the next interrupt.
The second step is balancing or calibrating the modulation frequencies of the launcher 12 to that of the missile 18. The high-speed input data available interrupt (HSI-D-A) routine is used in the balance process when the microcontroller receives HSI-D-A interrupts. The HSI-D-A interrupts are generated from an unmodulated (no CVAC signal present) constant frequency pitch and yaw calibration signal sent from the guidance unit 28 to the missile 18 prior to first motion of the missile 18. The calibration signal passes through the squaring circuits 48 and 50. The HSI-D-A interrupt is keyed by periodic zero-crossing transitions of the calibration signal. It is the time segment between each interrupt that determines the digital output value of the discriminators 66 and 68. When the discriminated output values from the pitch and yaw balance filters 86 and 88 equal zero, the guidance unit 28 is calibrated to the missile electronics unit 36.
The third step is to detect first motion of the missile 18. Motion of the missile 18 is determined when wire 31 between the missile 18 and the launcher 12 breaks, thereby breaking a ground connection to an input port of the microcontroller 70. The breaking of the wire is sensed by the microcontroller 70 as an external interrupt. An external interrupt invokes the external interrupt service routine, which sets a flag to indicate that first motion has occurred. After first motion, the pitch and yaw balance filters 86 and 88 are decoupled from the discriminators 66 and 68 and the pitch and yaw steering filters 72 and 74 are coupled to the discriminators 66 and 68.
The fourth step is to receive steering signals from the guidance unit 28. Receipt of steering signals generates HSI-D-A interrupts within microcontroller 70. The HSI-D-A routine determines whether the interrupt was generated by a pitch or a yaw signal transition. Subsequent to first motion, the routine performs pitch or yaw steering command discriminator processing. It filters the pitch or yaw steering signals using bilinear transform techniques as they pass through the pitch and yaw steering filters 72 and 74 and then stores them in memory 78 to await further processing.
The fifth step is to receive roll and yaw error signals from the attitude position sensing circuit 56. Receipt of roll and yaw error signals generates an analog-to-digital conversion complete interrupt (AD-CONVR). Prior to launch, the gyro outputs are calibrated by the software. In flight, the AD-CONVR routine filters the appropriate gyro data using bilinear transform techniques and scales the result for use in generating control actuator commands. The gyro data is stored in memory 78 to await further processing. The yaw gyro data is discarded if the yaw disable flag has been set.
The sixth step is to combine the pitch and yaw steering signals with the roll and yaw error signals and generate control actuator commands. The HSI-D-A routine executes a function for generating the commands. Provision is also made within the HSI-D-A routine for the additional steps of receiving a shutter control signal from the guidance unit 28, determining the status of the shutter 96, and generating a pulse for opening or closing the shutter 96.
Although the invention has been described with particular reference to certain preferred embodiments thereof, variations and modifications can be effected within the spirit and scope of the following claims. For example, while the microcontroller 70 of the preferred embodiment is commercially available from Intel Corporation as model number 8397, other suitable programmable machines can be employed. | An apparatus for controlling an airborne vehicle (18) includes a guidance unit (28), remotely located from the vehicle (18), for generating frequency modulated steering and control signals. A signal conditioning circuit (38) within the vehicle (18) conditions steering and control signals from the guidance unit (28). An attitude position sensing circuit (56) within the vehicle (18) senses and generates vehicle attitude position information. A programmable microcontroller (70) within the vehicle (18) receives the steering and control signals from the signal conditioning circuit (38) and vehicle attitude position information from the attitude position sensing circuit (56), and generates flight commands for controlling the flight of the vehicle (18). | 5 |
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to fluid ejection systems having fluid ejection heads and replaceable fluid supply cartridges.
2. Description of Related Art
Fluid ejection systems, such as, for example, ink jet fluid printers and plotters, have a fluid ejection head with a fluid supply, either integral with the fluid ejection head, or connected to the fluid ejection head. A fluid ejection head contains a plurality of fluid channels that carry fluid from the fluid supply, such as, for example, a fluid supply cartridge, to respective fluid ejecting nozzles. A maintenance/capping station is often provided in such fluid ejection systems. At the end of an ejection operation, the fluid supply cartridge and fluid ejection head face are placed opposite the maintenance/capping station. The maintenance/capping station includes a capping chamber and an associated suction pump communicating through a waste tank and conduit lines. The capping chamber is movable into and away from the fluid ejection head. The capping chamber is used to prime the fluid ejection head with fluid when connected to the fluid ejection head and suction is applied to draw fluid through the fluid ejection head openings, as well as to remove dried fluid, contaminants and gas bubbles from the fluid ejection head.
Fluid ejection systems, such as ink jet printers and plotters, typically use four different color fluids, such as, for example, the three subtractive primary colors of cyan, yellow and magenta, and the achromatic color black. Ink jet printers and plotters may use different numbers of ink supply cartridges, such as, for example, four separate ink supply cartridges or two ink fluid supply cartridges, one having three compartments for the primary color inks, and the other ink tank having black ink. Alternatively, one tank with four compartments may be provided for the four different color inks.
If the user of a fluid ejection system, such as an ink jet printer or plotter, changes an ink color or type of ink being used in the fluid ejection system, such as, for example, a change from certain subtractive primary inks to pantone color or photographic color inks, if the new ink is incompatible with the old ink, the quality of the printed product or printed image will be decreased, often to the point of being unfit for its intended use. One way to avoid ink incompatibility problems is to insure that new inks are backward compatible with older inks or different types of ink. Unfortunately, this is not always possible.
U.S. Pat. No. 5,634,170 to Knapp et al. discloses a method and apparatus for filtering and sensing a developer fluid in a printing or copying machine to ensure that developer fluid reclaimed from a developing process is free from contamination. In col. 7, lines 34-45, Knapp et al. teaches an advantage of having a filtering station when the color of toner at a developing station is changed to another color of toner, for example, when a specialty of custom color toner has been used in a developer housing and is replaced with another color toner. Knapp et al. points out that it is very important that the reclaimed fluid be free of the first color of toner so that the second color of toner is not contaminated with the first color of toner, especially when a dark colored toner is replaced with a light color toner. Knapp et. al also teaches a toner sump cleaning mode in col. 12, lines 5-17, where cleaned reclaimed fluid is circulated through the filtering/sensing process until the fluid in the toner sump is free from toner. Then another color toner can be added to the toner concentration holding station. Knapp et al. also teaches having cleaned fluid travel to the diluent holding station rather than to the toner sump when desired.
SUMMARY OF THE INVENTION
This invention provides systems and methods that allow incompatible fluids to be used in a fluid ejection system.
This invention separately provides systems and methods for flushing a fluid ejection head connected to a removable fluid supply tank.
This invention further provides systems and methods that flush a fluid ejection head using a fluid supply tank containing a flushing fluid.
This invention also provides systems and methods that flush a fluid ejector head using at least two distinct fluids contained in at least two fluid supply tanks that are separately used to flush the fluid ejector head.
This invention also conditions the fluid injector head and a maintenance/capping station of a fluid ejection system to fluids distinct from existing and/or previously used fluids.
The systems and methods according to this invention provide a simple, easy-to-use cleaning technique for fluid ejection systems, including ink jet printers, which does not involve a separate toner concentration holding station, a diluent holding station with separate diluent supply lines, a toner sump, or elaborate sensing equipment.
The systems and methods according to this invention modify known fluid supply cartridges by filling one or more of such fluid supply tanks with one or more of a flushing fluid an ejection-fluid ink miscible fluid, such that the fluid supply tanks become flush tanks. Depending on the composition of the original ejection fluid relative to the composition of the new or replacement ejection fluid, more than one flush fluid may be required to achieve an effective flushing of the old fluid from the fluid ejection system. In various exemplary embodiments, in situations where more than one flush fluid is required, one flush fluid may be used to flush the original ejection fluid from the fluid ejection head and/or the maintenance/cap mechanism of the fluid ejection system. The second flush fluid is then used to condition the fluid ejection head and/or the maintenance/capping station for the new ejection fluid.
In various exemplary embodiments, the fluid ejection systems and methods according to this invention employ a fluid ejection head that accommodates different ejection fluid supply tanks. In this case, a flush tank is loaded into the fluid ejection head in the same manner as the standard ejection fluid supply tanks. When the fluid ejection system is an ink jet printer, for example, the flush tank contains a colorless, or slightly tinted, fluid so that the flush tank can be distinguished from an ink supply tank. The flush tank cleaning and conditioning fluids are used to clean the fluid ejection head and/or the capping/maintenance station components. The waste tank portion of the capping/maintenance station is used to collect all fluids ejected into the maintenance/capping station, whether one or more fluid ejection heads are used. The fluid receiving caps and the fluid lines to the waste tank portion of the capping/maintenance station can also be cleaned using the flush fluids
These and other features of the invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of the systems and methods according to this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Various exemplary embodiments of this invention will be described in detail, with reference to the following figures, wherein:
FIG. 1 is a perspective view of a conventional ink jet fluid printer having a printhead and a capping/maintenance station; and
FIG. 2 is flowchart outlining one exemplary embodiment of a method for flushing a fluid ejector according to this invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
The following detailed description of various exemplary embodiments of the fluid ejection systems according to this invention are in part directed to one specific type of fluid ejection system, an ink jet fluid printer, for sake of clarity and familiarity. However, it should be appreciated that the principles of this invention, as outlined and/or discussed below, can be equally applied to any known or later-developed fluid ejection systems, beyond the ink jet fluid printer specifically discussed herein.
FIG. 1 shows one exemplary embodiment of an ink jet printer 10 that uses one or more ink supply containers 18 connected to the fluid ejector 20 . The ink jet printer 10 also includes a capping/maintenance station 30 that includes a cap chamber 33 usable to cap fluid ejector 20 . At the end of a fluid ejection operation, the scanning carriage (not shown) is parked in a maintenance position confronting the maintenance station 30 . The maintenance station includes a chamber 33 and an associated suction pump 32 in communication with each other through a waste tank 31 . The fluid lines 35 and 36 interconnect the interior of the chamber 33 with the waste ink tank 31 and the waste ink tank 31 with the suction pump 32 , respectively. The chamber 33 is movable toward and away from the fluid ejection head 20 .
Routine maintenance performed to clean debris, including dried ink and other materials, from each fluid ejector 20 is performed by covering each fluid ejector 20 with the corresponding cap of the capping/maintenance unit 30 . Ink flows through the fluid ejector 20 . Contaminants, including contaminated ink, are collected in the capping maintenance unit 30 and are drained by suction from the suction pump 32 into the waste ink tank 31 . The capping/maintenance station unit 30 may be used to cap the fluid ejector 20 when the ink jet printer 10 is idle, to reduce evaporation from, and drying of, ink in the fluid ejector 20 .
As an ink cleaning liquid, the flush fluid may be made up of one or more ink solvents without ink dye or pigment particles, or contain such low amounts of ink so as to constitute an indicator of the type ink with which the cleaning liquid is to be used, but not enough ink to materially contaminate other inks to be used later in the printer 10 . The ink cleaning liquid may contain surfactants and/or chelating agents that allow adsorbed contaminants and deposits to be relatively easily removed from the fluid ejector 20 and from other fluid passageways in the ink jet printer 10 . When used by a customer, the flush fluid supply cartridges are installed in the fluid ejector 20 in place of the original ink tanks 18 .
The user then operates the ink jet printer 10 to clean the fluid circuit of the ink jet printer 10 . A fluid circuit “clean” function may be performed directly with a user interface of the ink jet printer 10 such as, for example a touch screen, indirectly via a self-contained separate controller, or via a separate computer such as, for example, a personal computer. The “clean” function flushes old, incompatible ink from the fluid ejector 20 and the maintenance/cap station 30 so that, ideally, all vestiges of “old” incompatible ink are removed. For example, when a user wants to install ink fluid supply cartridges which contain ink which is not fully compatible with the previously or currently installed ink supply tanks, the “clean” function may be performed through a user interface to clean the fluid ejector 20 and the cap/maintenance station 30 and the associated fluid conduits.
FIG. 2 shows a flowchart outlining one exemplary embodiment of a method for flushing a fluid ejector head according to this invention. A user starts the flush operation. A flush operation can be started by, for example, selecting a start operation activator, such as, for example, a push button or touch screen portion located on the printer. Alternatively such a selection may be made by way of a display on a personal computer device, or by any other suitable interface with a printer controller.
The flush operation begins in step S 100 and continues to step S 110 , where the fluid ejector 20 moves to a cartridge change position. Once the fluid ejector 20 is located at the position where the cartridge or ink tank 18 can be changed, that fact may be displayed on the printer or on an associated display, such, as for example, on a personal computer. Next, in step S 120 , the user then replaces one or more ink tanks 18 with one or more flush tanks. Once this is done, suitable sensing elements can signal that the flush tank(s) 18 have been inserted, and this information can also be displayed to a user. Then, in step S 130 , the user inputs a clean command to the printer directly or through a device, such as a computer, which is interfaced with the printer. Control then continues to step S 140 .
In step S 140 , the printer moves the fluid ejector 20 to the maintenance/capping station 30 . Then in step S 150 , the maintenance/capping station 30 pump is turned on. This can be done manually by the user via a button or other input device on the printer or via an interfaced computer, or it can be done automatically by the printer as part of a sequence of system flush commands. Next in step S 160 , the suction pump 32 flushes the fluid ejector 20 and/or the maintenance station 30 , including any fluid lines connecting the fluid ejector 20 and the maintenance station 30 , the waste ink tank 31 and the fluid lines 35 and 36 in the ink jet printer. Control then continues to step S 170 .
Flushing the fluid ejector 20 and/or these other elements can be accomplished by operating the flush pump for a predetermined amount of time, by flushing with a predetermined volume of cleaning fluid, and/or by real-time sensing a suitable parameter of the fluid, such as, for example, the optical density or electrical capacitance of the flushing fluid. In the last case, sensors (not shown) would be provided to detect a suitable parameter, such as, for example, the optical density or the electrical impedance or conductivity, of the ink flushed from the capping/maintenance station 30 and/or fluid ejection head 20 . These sensors would provide one or more signals to the printer to shut off the suction pump 32 to terminate the flush operation when a desired flush fluid characteristic is achieved. When the flush operation has been performed, the printer may indicate that the flush operation is completed by displaying, for example, a “flush complete” message or other suitable message.
In step S 170 , the fluid ejector 20 is moved to the cartridge change position. This can be done automatically or manually. Next, in step S 180 , a determination is made whether a second or subsequent flush cartridge 18 needs to be used. This determination can be made automatically, based on the user identifying the name or identifier of the new ejection fluid composition to be used, or in any other known or later-developed manner. Alternatively, this determination can be made manually, by prompting the user with a query regarding whether there is another flush cartridge 18 to be installed.
If another flush fluid supply cartridge 18 is to be installed, control continues to step S 190 , where the next flush cartridge is installed in place of the previous flush cartridge. Control then jumps back to step S 140 . In contrast, if not, control jumps to step S 200 , where the user replaces the current flush ink fluid supply cartridges 18 with new or upgrade ink fluid supply cartridges 18 . The printer may indicate that the flush fluid supply cartridges 18 have been replaced by ink fluid supply cartridges, i.e., by sensing a characteristic of the ink tank(s), such as, for example, a bar code label or any other known or later-developed method for encoding information into or onto the ink fluid supply cartridges 18 . Then, in step S 210 , once the replacement ink cartridge(s) have been inserted in place of the flush cartridges, the clean/flush operation is terminated. This may be accomplished automatically or manually. This operation results in an upgraded image transfer engine ready to use the new or upgraded ink without fear of contamination by the previously-used ink.
It should also be appreciated that the systems and methods of this invention can also be used with fluid ejection systems that do not have maintenance stations. In such fluid ejection systems, the fluid ejection heads are cleaned by firing fluid drops onto a receiving medium. This receiving medium is used in place of the waste fluid tank to receive and/or absorb the waste drops created during the cleaning process. This receiving medium is then discarded.
Likewise, in the systems and methods according to this invention, the flush fluid drops can be ejected onto a waste receiving medium in place of ejecting the flush fluid drops into the maintenance cap outlined above. In this case, only the fluid ejection head will need to be cleaned, and the maintenance station 30 and its various subsystems will be omitted. Likewise, steps S 140 and S 150 would be omitted, and step S 160 would be modified to merely flush the fluid ejector head 20 .
While this invention has been described in conjunction with the exemplary embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the exemplary embodiments of the invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention. | An improved method of upgrading an image transfer engine such as, for example, an ink jet fluid printer or plotter using liquid ink, or a xerographic device using a liquid toner is disclosed. A removable ink flush tank/cartridge containing an ink cleaner is substituted for a removable ink tank, permitting complete cleaning of ink from the ink fluid flow paths in the engine. This results in less contamination of new inks with previously used inks in the engine. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a sorter which is provided to an image forming apparatus such as a copier and printer to sort sheets discharged from the apparatus, and more particularly relates to a sorter having a plurality of bins, and the sorter is provided with a stapling device to arrange and staple the sheets in the bin.
For a sheet processing device provided with a stapling device to staple sheets discharged from a copier, printer and the like, a sheet finisher has been utilized which is installed together with an automatic recirculating document handler in order to staple the sheets. However, the aforementioned sheet finisher is disadvantageous because the structure is so complicated and expensive.
(1) In Japanese Patent Publication Open to Public Inspection no. 43457/1989, has been disclosed an apparatus in which a stapling device is provided to a relatively simple bin-moving type of sorter. In the aforementioned apparatus, a stapling device to staple sheets sorted into a bin can be freely moved with regard to the bin.
(2) Another sorter is composed in such a manner that: a fixed type of stapling device is provided to each bin; and the bin is moved to the stapling position so that a bundle of sheets can be stapled.
(3) A sorter disclosed in the official gazette of Japanese Patent Publication Open to Public Inspection No. 244869/1987, is composed in such a manner that: a bin having sheets is moved to a position where a stapling operation can be conducted; the sheets are stapled by a stapling device; and when the sheets in other bins are stapled, the stapling device is moved in a vertical direction.
In the aforementioned sorter of case (1) having a stapling device which can be moved freely, the moving stroke of the stapling device is different according to sheet size. Accordingly, when the vertical spacing of each bin is set large, the sorter size becomes large as a whole, and when the vertical spacing of a bin into which the stapling device is inserted, is extended, the mechanism becomes complicated.
In the aforementioned sorter of case (2), the structure of the sorter is complicated as a whole, and in the case where the vertical spacing of the bin is small, a special stapling device is required.
In the aforementioned sorter of case (3), each bin in which sheets are put, is moved straight along a bin guide at an appropriate time. Accordingly, it is disadvantageous in that the structure becomes complicated.
In any sorters, when the sheets aligned on a bin are moved to a stapling position, or when the stapler is inserted between bins, the bundle of sheets are not fixed at all, so that the sheets are stapled without being aligned before the stapling operation. Accordingly, the bundle of sheets becomes irregular.
The first object of the present invention is to provide a composition by which sheets can be stapled at a constant position even in the case of a relatively simple sorter when the sheets are fixed being aligned just before the bin is moved.
As sorter systems which automatically sort a plurality of sheets (copy sheets) discharged from an image forming apparatus such as a copier, there are a fixed bin system, an all bin shifting system, and a bin opening movement system.
In the case of the fixed bin system, a plurality of copies are made from a plurality of documents by an image forming apparatus in such a manner that: the sheets conveyed from the image forming apparatus are successively received by a receiving section of a sorter; then the sheets are moved to a conveyance section; as shown in FIG. 1, while the sheets are being conveyed, they are successively taken into bins 41 by a sorting guide 36 and a delivery roller 35 which are installed in the receiving portion of the bin 41.
The aforementioned bin fixed system is advantageous in that: a relatively large number of sheets can be put into the bin: the sorter can respond at a high speed; and a plurality of sorters can be connected. Therefore, this type of sorter is frequently applied to a console type of high speed copier. For example, 50 sheets can be stacked in each of the bins for sorting use, and 250 sheets can be stacked on a tray for non-sorting use.
The sheets discharged from the aforementioned image forming apparatus are received by the sorter of the aforementioned bin fixed system, and then conveyed at a high speed in a conveyance passage formed in the sorter into the aforementioned bins through the aforementioned branch means.
When a sheet SA2 of a small size conveyed to the bin at a high speed is discharged, sheet SA2 is branched by the branch means 36, pinched by the paper discharging roller 35 and the conveyance belt 31, and discharged at a high speed as shown in FIG. 25(A). Since the weight of small-sized sheet SA2 (for example, a sheet of B4-size or A4-size) is light, an area of the frictional surface of the sheet is small, so that sheet S2A is carried too far jumping over the uppermost portion of the stacked sheets and does not slip down to a predetermined position. Accordingly, sheet S2A is not contacted with stopper wall 41S of the bin 41, so that the bundle of sheets become irregular. When the following sheets are discharged into the bin 41 under the aforementioned condition, the sheets are bumped with each other and a failure in conveyance such as a jam occurs. The conveyance failure tends to occur when a large number of sheets are stacked in the bin 41. In the case of a sorter provided with a stapler, the irregular bundle of sheets are stapled.
When a large-sized sheet S2B (for example, A3-size or B4-size) is discharged onto the bin 41, sheet S2B comes into contact with the uppermost sheet as shown in FIG. 25(B) since the weight of sheet S2B is heavy and the frictional surface is large, so that the movement of sheet S2B is interrupted. Therefore, the trailing edge of the sheet remains on the upper edge of the stopper wall of the bin 41, so that a jam is caused.
The second object of the present invention is to solve the aforementioned problems, and more particularly to provide a sorter characterized in that: a jam caused by a failure in sheet conveyance can be prevented when sheets are conveyed at a high speed; and the sheets can be positively aligned in the bin.
SUMMARY OF THE INVENTION
The present invention has been achieved under the circumstances described above. A sorter with a stapler according to the present invention by which the aforementioned first object can be accomplished, having a plurality of bins to sort and hold discharged sheets, and a stapling device to staple the sheets held in the aforementioned bins, comprises: a bin oscillating means which oscillates the sheets stacked in the aforementioned bins to set the sheets in a position where a stapling operation can be conducted; and a sheet holding means which presses the upper surface of the sheets immediately before the oscillation of the bins to fix the sheets to the bins so that the sheets can be maintained to a stapling position.
The sorter to accomplish the aforementioned second object of the present invention which conveys sheets discharged from an image forming apparatus and sorts the sheets into a plurality of bins, comprises: a sheet conveyance drive means to variably change the linear velocity of sheets discharged into the aforementioned bins; and a control means to variably control the linear velocity of the sheets discharged by the aforementioned sheet conveyance drive means, wherein the linear velocity of small-sized discharged sheets is set lower than that of large-sized discharged sheets.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view showing the structure of a sorter connected with an image forming apparatus body;
FIGS. 2A and 2B are partial sectional views of the members of the branched conveyance passage for papers, and the bins of the sorter;
FIG. 3 is a plan view of a bin;
FIG. 4 is a sectional front view of the alignment device;
FIG. 5 is a plan view of the alignment device;
FIG. 6 is a perspective view of a bin to which the paper holding device is provided;
FIG. 7 is a plan view of a bin oscillating device;
FIG. 8 is a plan view showing the progress of oscillation of various sizes of papers which are set in such a manner that the sides of the papers coincide with a reference line.
FIG. 9 is a plan view showing the straight motion of a bin;
FIG. 10 is a plan view showing the progress of oscillation of a bin;
FIG. 11 is a timing chart of essential composing members of a sorter;
FIG. 12 is a perspective view of a bin provided with a paper pressing device;
FIG. 13 is another perspective view of the aforementioned bin;
FIG. 14 is a plan view showing straight movement of the aforementioned bin;
FIG. 15 is a plan view showing the progress of oscillation of the aforementioned bin;
FIG. 16 is a sectional view of an upper portion of the alignment device of the third embodiment;
FIG. 17 is a front sectional view showing the progress of oscillation of an arm and alignment rod of the bin alignment device of the third embodiment;
FIG. 18 is a plan view showing the straight movement of the aforementioned bin;
FIG. 19 is a plan view showing the progress of oscillation of the aforementioned bin;
FIG. 20 is a view showing the structure of a sorter connected with the image forming apparatus of the fourth embodiment to achieve the second object of the present invention;
FIG. 21 is a sectional view showing an essential portion of the sheet conveyance system of the aforementioned sorter;
FIG. 22 is a sectional front view of the drive means of the sheet conveyance system of the aforementioned sorter;
FIG. 23 is a plan view of the aforementioned drive means;
FIG. 24 is a block diagram of the sheet conveyance control means of the aforementioned sorter;
FIGS. 25A and 25B are schematic illustrations of a conventional example of a sorter by which different sizes of papers are discharged into a bin;
FIG. 26 is a perspective view taken from the bottom side of a bin; and
FIG. 27 is a plan view of a bin and guide plate showing another embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the drawings, the first embodiment of the present invention will be explained as follows.
FIG. 1 is a view showing the structure of a sorter which is connected with a main body 1 of an image forming apparatus (for example, a copier). The sorter of the present invention comprises a base frame 10, downward conveyance section 20, upward conveyance section 30, and bin shift section 40.
The base frame 10 includes a caster 11, connecting means 12 to connect the base frame 10 with a recording unit, conveyance belt 13, idle roller 14, guide plates 15A, 15B, and drive means (not shown in the drawing), and the base frame 10 is fixed to the floor.
The downward conveyance section 20 is connected with paper discharging rollers 2 and a discharging port 3 of the image forming apparatus 1. The downward conveyance section 20 is composed of a guide plate 21 to receive a discharged sheet P so that it can be conveyed downward, a conveyance belt 22 and idle rollers 23 to convey sheet P to the conveyance belt 13 in the aforementioned base frame 10, and the like. A conveyance means 24 and tray 25 are branched from the conveyance passage, which are utilized for discharging a preceding sheet in the image forming apparatus 1 when a jam has occurred in the image forming apparatus 1. The upper portion of the frame corresponding to the aforementioned downward conveyance section 20 is freely opened and closed so that a jammed paper in the downward conveyance section 20 can be removed.
In the upper conveyance section 30, several endless conveyance belts 31 are provided between pulleys 32 and 33 which are rotatably mounted on the upper and lower portion of the support frame. A plurality of rollers 34 corresponding to the insert ports of the bins are provided inside the conveyance belt 31 in such a manner that the rollers 34 are rotatably contacted with the conveyance belt 31. A plurality of conveyance rollers 35 are provided outside the conveyance belt 31 correspondingly to the rollers 34 in such a manner that the conveyance rollers 35 are rotatably contacted with the conveyance belt 31.
Branch guides 36 are disposed between the conveyance rollers 35 at the entrances of the bins, and oscillated to guide the papers. These branch guides 36 are rotatably supported by shafts 37 which are provided to the aforementioned support frame, and oscillated by levers provided at the ends of shafts 37 and solenoids, wherein the levers and solenoids are not illustrated in the drawing. Accordingly, when a branch guide 36 is rotated clockwise, the lower edge claw portion of the branch guide 36 is crossed with a paper conveyance passage composed of the conveyance belt 31 and the conveyance roller 35 so that the paper can not be conveyed upward. In this way, the branch guide 36 is prepared for receiving papers. When a paper P is conveyed under the aforementioned condition, paper P is curved along the inner curved surface of the branch guide 36 in the direction of a right angle, and paper P is received by bin 41.
FIG. 2 is a partial sectional view of the composing members of the aforementioned branch conveyance passage and the bin.
FIG. 3 is a plan view of the bin 41.
In the bin shift section 40, a plurality of bins (for example, 20 bins) 41 which are disposed at regular intervals, are supported in such a manner that the bins can be freely oscillated. That is, the bottom portion (the left portion shown in FIG. 2) of the bin 41 is slidably supported on a guide plate 48 which is fixed to the bin shift section 30.
A vertical fixed shaft 43 which is supported by supporting members 42 mounted on the upper and lower portions of the frame of the bin shift section, is engaged with a slide member 44 which is positioned by a pin 45. The slide member 44 is inserted into a hole formed at one end (the right upper portion shown in FIGS. 2 and 3) of the aforementioned bin 41, so that the bin 41 can be freely rotated. The pins 45 mounted on the fixed shaft 43 at regular intervals, are engaged with the cut-out portions of the slide members 44, so that the edge portions of the bins 41 are held in parallel at regular intervals.
The other end portion of the bin 41 is supported by a rotatable roller 39 which is mounted on a portion of the frame of the bin shift section 40. In the manner described above, the bin 41 is supported by the guide plate 48, slide member 44 and roller 39, and freely rotated around the fixed shaft 43. Numeral 41A in the drawing represents 3 claws which engage with cut-out portions of the guide plate 48. Numeral 41B represents 5 front stoppers provided on the paper guide side of the upper surface of the bin 41. The upper edge of the vertical surface of the stopper is curved so that it can be formed claw-shaped in order to prevent a paper from getting out of the bin in the case where the trailing edge of the paper is raised.
On the other hand, an alignment member 50 which aligns the side of paper P discharged from the copier 1 onto the bin 41, is provided in one portion of the fixed frame of the upward conveyance section 30. FIG. 4 is a sectional front view of the alignment device 50, and FIG. 5 is a plan view of the alignment device 50.
In the alignment device 50, a lower arm 52 is engaged with a lower shaft 51 mounted on the lower portion of the aforementioned frame so that it can be freely oscillated by a pulse motor (not illustrated in the drawing). A lower shaft end of a core bar 54A of an alignment rod 54 is supported by an aligning bearing 53A at the tip of the lower arm 52. The circumference of the core bar 54A of the alignment rod 54 is covered with a resilient member 54B made of a foam material such as sponge, and the resilient member 54B is contacted with the side of paper P so that the side of paper P can be aligned.
An upper shaft end of the core bar 54A of the aforementioned alignment rod 54 is supported by an aligning bearing 53B mounted on the shaft end of an upper arm 55. The upper arm 55 is engaged with an upper shaft 56 mounted on the upper portion of the aforementioned frame so that the upper arm 55 can be rotated.
An arc-shaped curved portion 52A is protruded from a portion of the aforementioned lower arm 52, and when an optical path of a photo-interrupter 57 is interrupted, the home position of the lower arm is detected.
The oscillating angle of the aforementioned lower arm 52 can be changed when the setting pulse number of the aforementioned pulse motor is changed so that paper P can be aligned in accordance with the size of paper P.
A roller 58 is rotatably engaged with a protruded shaft portion 52B which is protruded from a portion of the aforementioned lower arm 52. The roller 58 is slidably contacted with a groove cam portion 59A of a cam member 59 which is fixed to the aforementioned frame. Accordingly, when the lower arm 52 is oscillated around the lower shaft 51, the lower arm 52 is also oscillated in the direction of the shaft. When the aforementioned oscillation is conducted, papers P put on the bin 41 are aligned by the oscillation of the alignment rod 54, and the side of the paper can be pressed downward so that the paper can be aligned.
The aforementioned alignment rod 54 moves along a locus which is shown by a one-dotted chain line in FIG. 3. On the other hand, in order to insert papers on the bin 41 into a stapling member, the bin 41 is oscillated as shown by a one-dotted chain line in FIG. 5. Since the bin 41 is moved forward and backward, a large curved opening portion 41C is formed in the bin 41 as shown in the drawing so that the alignment rod 54 can not interfere with the bin 41. Numeral 46 is a reinforcing member to reinforce the opening portion 41C of the bin 41 in order to prevent deformation of the bin 41 caused by the opening portion 41C. This reinforcing member is fixed to the side of the bin 41 by screws, and at the same time engaged with a groove of the bin 41 into which the aforementioned slide member 44 is inserted, in order to prevent the slide member 44 from getting out.
A stopper wall 41D is provided vertically on one side of the aforementioned bin 41. The inner side of the aforementioned stopper wall 41D is formed wave-shaped so that air can pass through a gap formed by the bundle stacked on the bin 41.
A vertical stopper wall 41D is integrally provided on the side of the aforementioned bin 41. A paper holding device 60 is mounted on the outer side of the aforementioned stopper wall 41D. FIG. 6 is a perspective view of the bin 41 to which the paper holding device 60 is provided. A lever 61 is supported by a shaft 62 mounted on the outer side surface of the stopper wall 41D in such a manner that the lever 61 can be freely oscillated. Numeral 41E is a guide portion to slidably guide the lever 61. A long and slender shaft 63A is mounted on the tip of the lever 61, and a pipe-shaped member 63B is provided around the shaft 63A with play. The other end of the aforementioned lever 61 is resiliently pressed by a leaf spring 65. A leaf spring 66 is supported and fixed in the manner of a cantilever at a bending portion located under a position where the lever 61 is pushed by the spring. The leaf spring 66 is pushed by a roller 72 mounted on the tip of the second arm 71B of a bin oscillating device 70.
FIG. 7 is a plan view of the bin oscillating device 70 which oscillates the aforementioned bin 41 and at the same time activates the aforementioned paper holding device 60.
The bin oscillating device 70 is mounted on a base plate 73. The first arm 71A is coaxially provided to a rotating shaft 74 which is driven by a motor and reduction gear train not illustrated in the drawing. The second arm 71B having long holes is provided to the first arm 71A in such a manner that it can be slid in the radial direction being pushed by a spring. A rubber coated roller 72 is mounted on the tip of the second arm 71B.
A cam plate 75 is provided to the aforementioned rotating shaft 74, and the cam plate 75 is composed of a U-shaped groove and an arc portion having the same radius.
On the other hand, a follower shaft 78 is supported being pushed by a spring, wherein the follower shaft 78 penetrates through a long groove portion of a moving member 77 which slides straight on a guide member 76 mounted on a portion of the base plate 73, the aforementioned first arm 71A, and the second arm 71B.
A semicircular shut-off plate 75A is integrally provided at the other end of the aforementioned cam plate 75, so that a photo-interrupter 79 is turned on and off.
When the aforementioned first arm 71A is rotated clockwise as shown by a broken line in FIG. 7, the follower shaft 78 moves the groove portion of the moving member 77 and at the same time moves the groove of the cam plate 75 to the outside. After the follower shaft 78 leaves the grooves, it slides on the curved surface of the arc portion having an equal radius. Before the aforementioned operation, the shielding plate 75A of the tail portion of the cam plate 75 interrupts the optical path of the photo-interrupter 79 so that the power source is turned off and the rotation of the motor is stopped. Consequently, even when there is an overrun after the motor has been stopped, the follower shaft 78 moves and stops on the arc portion having the equal radius of the cam plate 75, so that the first arm 71A maintains its stop position at a predetermined angle. Accordingly, the bin 41 stops at a predetermined position.
The base plate 73 of the aforementioned bin oscillating device 70 is mounted on the common frame 82 together with the base plate 81 of the stapling device. The base plate 73 moves vertically on the frame of the aforementioned bin shift section 40, and stops at each bin 41. Then, a bundle of papers stacked on the aforementioned oscillated bin 41 being held by the aforementioned paper holding device 63B, enter into a stapling gap of the stapling device to be stapled.
After the bundle of papers have been stapled, the second arm 71B is oscillated back so that the bin 41 is returned to the original paper discharging position being pushed by a spring.
Next, the stapling operation conducted on the bundle of papers discharged in the bin 41, will be explained as follows.
When the position of a document is determined on the platen glass of the copier 1, there are two manners, one is a manner in which the document is set so that the center of the document can coincide with the center line of the copier, and the other is a manner in which the document is set so that one side of the document can coincide with a reference line. The stapling operation conducted in the latter case will be explained here.
FIG. 8 is a plan view showing the progress of movement of paper P when the aforementioned bin 41 is oscillated.
(1) Papers P discharged from the copier 1 are pressed against the stopper wall 41D by an oscillating alignment rod 54 one by one so that the sides of papers P can be aligned along base line BL.
(2) When it is detected that a predetermined number of papers have been held in the bin 41, the second arm 71B of the aforementioned bin oscillating device 70 starts oscillation. The roller 72 mounted on the tip of the second arm 71B pushes the stopper wall 41F protruded to the lower side portion of the bin 41, through the spring 66 used for a buffer. Then, the lever 61 is oscillated against the force of the leaf spring 65, and the paper holding member 63B presses the bundle of papers from the upper side so that the slippage of papers can be prevented.
(3) When the aforementioned second arm is further oscillated, the bin 41 is oscillated around the slide member 44 while the papers are pressed in a manner described above, and the bin 41 reaches a position shown by a one-dotted chain line in FIG. 3. Then, the papers stacked on the bin 41 are oscillated to a position shown by a one-dotted chain line in FIG. 8 and stopped (a staple line SL).
(4) In this position, the leading edge portion of the papers is inserted into a gap formed in the stapling device 80, and a staple is hit into the papers to be stapled.
(5) After the stapling operation has been completed, the arm 71B is driven back to its initial position, and the bin 41 is returned to the original position by the force of a spring, and at the same time the paper holding member 62B is separated from the surface of the bundle of papers so that the bundle of papers can be taken out from the bin 41.
(6) After a stapling operation of the uppermost bin 41 has been completed, a common frame 82 in which the stapling device 80 and the bin oscillating device 70 are integrally formed, is lowered by a drive source, and then a bin 41 located below the uppermost bin is oscillated and a stapling operation is conducted in the same manner. While the aforementioned stapling operation is being conducted, papers stacked on a bin located below the aforementioned bin are discharged.
The stapling operation conducted in such a manner that the sides of papers are aligned along the stopper wall 41D (base line BL), is described above. Next, the stapling operation conducted in such a manner that the center of papers coincide with center line CL, will be explained as follows.
The first method is as follows:
Each of the papers discharged from the copier 1 is pushed by the aforementioned alignment rod 54 so that the paper can be bumped against the stopper wall 41D so as to be aligned in a position shown in FIG. 8. After that, the bin 41 is oscillated and stapled in the same manner as described before.
Although the drive structure of this method is simple, the displacement amount of a paper on the bin differs according to the paper size. Especially, in the case of a small-sized paper (for example, B5 size paper), the displacement amount on the bin 41 is large (which is W shown in the drawing), so that alignment can not be conducted positively.
The second method is as follows:
The entire bin movement section 40 including the bin 41 is moved forward in a direction perpendicular to the paper discharging direction in which the papers on the bin are trued corresponding to the paper size so that the papers are located at the same location as the one-sided.
A stapling operation conducted according to this method is shown in the time charts of FIGS. 9, 10 and 11. This stapling operation will be explained as follows.
(1) After the size of paper (copy paper) discharged from the copier 1 is manually set or automatically judged, the bin moving section 40 of the sorter is electrically driven. When the sorter has come to a predetermined position corresponding to the aforementioned paper size, the movement of the sorter is stopped and the sorter is placed in a waiting condition. When the sorter is located in this waiting position, the stopper wall 41D of the bin 41 is located in a position separated from the side of paper P by 1 (for example, about 10 mm).
(2) Under the aforementioned condition, paper P advances from the left in the drawing, and rises along the inclined surface of the bin 41. After that, paper P slips down by its own weight and stops coming into contact with the front stopper 41B of the bin 41.
(3) After the movement of paper P has stopped, the alignment rod 54 is oscillated, and one side of paper P is pushed so that paper P is moved by the displacement amount 1 to this side, and the other side of paper P is contacted with the stopper wall D. This displacement amount 1 is set to almost the same value even in the case in which paper sizes are different (for example, A4 size, B4 size and A3 size).
(4) FIG. 10 is a plan view showing the progress of oscillation of a bin while a stapling operation is being conducted. When a stapling signal is inputted into the bin movement section 40 which is in a stopped condition, first the aforementioned bin oscillating device 70 is driven, and then the arm 71B is oscillated so that the roller 72 mounted on the tip of the arm 71B pushes the leaf spring 66 provided in the lower end of the aforementioned paper holding device 60. Further, the lever 61 is oscillated counterclockwise around the shaft 62 against the force of the upper leaf spring 65. Accordingly, the paper holding member 63B presses the upper surface of the sheets stacked on the bin 41.
(5) Successively, the roller 72 mounted on the tip of the arm 71B is oscillated around the slide member 44 (by the angle of about 12°), and oscillates the bin 41 while the sheets on the bin 41 is being pressed.
(6) When the follower shaft 78 of the bin oscillating device 70 has risen to a circular arc curved surface formed by the outer diameter of the cam plate 75, the driving of the bin 41 is stopped by a signal sent from the photo-sensor 79 which detects the position, or even when the rotation is continued by an inertia effect, the position of the roller 72 is not changed and the oscillation of the bin is stopped.
(7) Then, a staple 83 is hit in the same manner as described before.
(8) Next, the returning operation of the bin oscillating device 70 starts, and the bin 41 and the paper holding member 63B are returned to the initial positions.
(9) Successively, the second and third bin are oscillated in the same manner and a stapling operation is conducted.
As explained above, according to the first example of the present invention, the bins in which sheets are stacked, are oscillated for a stapling operation, and immediately before the oscillation of the bins, the bundles of sheets are pressed on the bins by the sheet pressing device which presses the sheets against the bin surface, so that slippage of sheets can be prevented. Consequently, the stapling positions can be easily stabilized in all the bins, so that the sheets can be positioned to a predetermined stapling position by a simple device, and a bundle of sheets can be positively stapled.
Especially when the aforementioned sheet holding device is provided on a sheet bumping surface (a stopper wall), the sheet alignment and stapling operation can be conducted in a constant position irrespective of the sheet size, and the stapling viscosity can be increased.
FIG. 12 and FIG. 13 are perspective views of the bin 41 provided with the paper holding device 60 according to the second example.
The vertical stopper wall 41D is integrally provided on one side of the aforementioned bin 41. The inner side wall 41DA of the stopper wall 41D is a bumping surface against which the side edge of paper P is bumped so that the paper can be aligned. The aforementioned bumping surface is formed into a step-like shape having a plurality of protrusions and cut-out portions. The aforementioned protrusions are contacted with one side edge of paper P, and the cut-out portions are separated from the aforementioned side edge so as to form a gap. The air of an air layer formed between the papers stacked by the oscillation of the aforementioned alignment rod 54, is released to the outside through the aforementioned gap, so that the following problem can be eliminated: the stack thickness of papers P is increased, so that the successive paper P runs over the bumping surface to the outside of the bin; and papers can not be aligned.
The paper holding device 60 is provided on an outer side surface 41DB of the aforementioned stopper wall 41D. A lever 61 is rotatably provided to a shaft 62 which is fixed on to the outside surface 41DB of the stopper wall 41D. Numeral 41E is a guide which slidably guides the lever 61. A pipe-shaped paper holding member 63 is provided on one end of the lever 61. The other end of the lever 61 is resiliently pressed by a leaf spring 65. A leaf spring 66 is supported and fixed by a bent portion below the pressed portion of the leaf spring 66 in a manner of a cantilever. The leaf spring 66 is pushed by a roller 72 mounted on a tip of an arm 70 of a bin oscillating device 70 as shown in FIG. 15. The arm 71 is oscillated by a rotating shaft 74 which is driven by a motor not shown through a reduction gear train, and pushed by a spring so that it can be slid in a longitudinal direction of the arm.
A base plate 73 of the aforementioned bin oscillating device 70 is mounted on a common frame together with a base plate 81 of the stapler 80. The base plate 73 of the bin oscillating device is moved and stopped at each bin 41 by a lift not shown which is driven on the frame of the aforementioned bin moving section 40 in the up and down direction. Due to the foregoing, a bundle of papers which are stacked on the oscillated bin 41 being pressed by the aforementioned paper holding member 63, enter into a stapling gap of the stapler 80 so that a staple can be hit into the bundle of papers.
After the staple has been hit, the arm 71 is returned and oscillated, and the bin 41 is pushed by the spring, oscillated, and returned to the initial paper discharging position.
Next, a stapling operation of a bundle of papers discharged onto the bin 41 will be explained as follows.
When the position of a document is determined on the platen glass of the image forming apparatus 1, there are two manners, one is a manner in which the document is set so that the center of the document can coincide with the center line of the image forming apparatus, and the other is a manner in which the document is set so that one side of the document can coincide with a reference line.
Referring now to FIG. 14 and FIG. 15, a stapling operation conducted in the former manner will be explained here. FIG. 14 is a plan view showing a state of accommodation and alignment of papers on the bin 41, and FIG. 15 is a plan view showing a state in which the bin 41 is oscillated and stapled.
(1) When the size of a paper P (a copy paper) discharged from the image forming apparatus 1 is set manually or automatically, the bin shift section 40 of the sorter is driven electrically, and when the bin has reached a predetermined position corresponding to the size of the aforementioned paper, the bin stops according to a signal sent from a position detecting sensor. Therefore, the bin is set in a waiting condition. The maximum movement amount of the bin movement section 40 is determined in such a manner that: the minimum width of paper (for example, B5 size, 257 mm) is subtracted from the maximum width of paper (for example, 17 inches); and the obtained value is divided by 2 (for example, 87.4 mm can be obtained). In this waiting position, the stopper wall 41D of the bin 41 is located in a position which is separated from a side edge of the width direction of paper P by distance δ (for example 10 mm).
(2) In the aforementioned condition paper P enters from the left in the drawing, and moves upward along the inclined surface of the uppermost bin 41. After that, paper P slides down by its dead weight and bumps against a front stopper 41S to be stopped.
(3) After paper P has been stopped, the alignment rod 54 is oscillated and pushes one side edge of paper P to move it toward the viewer's side by the distance of δ, so that the other side edge of paper P can be contacted with the stopper wall 41D. This distance δ is set to almost the same in the case of other sizes (for example, A4 size, B4 size and A3 size).
(4) Successively, the following paper P is discharged into the second bin 41 by the branch guide 36, and the aforementioned alignment rod 54 is oscillated and pushes the side edge of paper P in the same manner as described above, so that paper P is contacted with the stopper wall 41D to be aligned.
(5) In the same manner as described above, papers are successively stacked in the bins, the number of which corresponds to that of document sheets.
(6) When a counter of CPU control detects that a predetermined number of papers P have been accommodated in the uppermost 41, and when it is detected that an optical path has been opened which is formed between a light emitting element LED provided to the upper portion of the bin movement section 40 and a light receiving element PT r provided to the lower portion so as to detect the passing of the trailing end of a final paper P, the discharging operation to the first bin 41 is completed. (Refer to FIG. 1.)
(7) Immediately after it is detected that a paper discharging operation to the second bin 41 has been completed, or after a predetermined period of time has passed after the detection, the aforementioned uppermost bin 41 is oscillated by the aforementioned bin oscillating device 70. When a stapling signal is inputted into the stopped bin movement section 40, the paper holding member 63 presses the upper surface of the sheets stacked on the bin 41 in such a manner that: first, the aforementioned bin oscillating device 70 is driven and the arm 71 is oscillated; the roller 72 mounted on the tip pushes the leaf spring 66 provided to the lower end of the aforementioned paper holding device 60; and further the roller 72 oscillates the lever 61 counterclockwise around the shaft 62, resisting the force of the leaf spring 65.
(8) Successively, the roller 72 mounted on the tip of the arm 71, is oscillated around the slide member 44 (for example, θ=12°) so that the bin 41 is oscillated while the sheets in the bin 41 are being pressed.
(9) A sensor of the bin oscillating device 70 detects the oscillating position and the oscillation of the bin 41 is stopped.
(10) In this stop position, a rear corner portion of the bundle of papers is inserted into a stapling gap of the stapler 80, and then the stapler 80 is driven and a staple 83 is hit.
(11) After the stapling operation has been completed, the arm 71 is driven to be returned, so that the bin 41 is pushed by a spring force and returned to the initial position, and at the same time the paper holding member 63 is separated upward from the surface of the bundle of papers. In this manner, the bundle of papers 41 can be taken out from the bin 41.
(12) After the bundle of papers accommodated in the uppermost bin 41 have been stapled, a unit in which the stapler 80 and oscillating device 70 are integrally provided, is lowered by a lift, and almost simultaneously the bin 41 positioned below the uppermost bin is oscillated and a stapling operation is conducted in the same manner. In the mean time, a paper discharging operation is conducted in a bin 41 located further below.
(13) When all the bundles of paper have been stapled, the unit in which the bin oscillating device and stapler have been integrated, is returned to the uppermost bin position.
The aforementioned stapling operation has been conducted on a sorter in which papers are aligned under the condition that a center of the paper discharged from the image forming apparatus 1 coincides with the center line of the apparatus 1. However, it should be understood that the present invention is not limited to the specific embodiment. The present invention can be applied to a sorter in which paper alignment is conducted so that one side of a paper can coincide with a reference line.
As explained above, the second embodiment of the present invention is characterized in that: a notch portion is provided to each bin; the shape of the notch is formed in such a manner that the aforementioned alignment member can be inserted into the notch from the outside when the bin is moved and the alignment operation is conducted; a portion close to the opening of the notch is fixed by a reinforcement member; and a bearing member which rotatably holds the bin, is positioned and fixed by the arm of the aforementioned reinforcement member. Therefore, assembly of the bin and alignment device and maintenance such as replacement of parts can be easily performed, and the size and weight of the bin can be reduced.
Next, the third embodiment of the present invention will be explained as follows.
The alignment device 50 is vertically supported by the upper and lower portion of the aforementioned frame. The alignment rod 54 is supported and oscillated by the upper arm 52B and the lower arm 52A which can be oscillated engaging with the rotating shaft 51, wherein the rotating shaft 51 is rotated by pulse motor M2 through a transmission system including gears G3, G4, G5 as shown in FIG. 16. Numeral 55 is a return spring which pushes the upper arm 52B wound around the rotating shaft 51. The tip portion of the upper arm 52B holds an upper end of the core bar 54A of the alignment rod 54 through the aligning bearing 53B. A lower end of the core bar 54A of the aforementioned alignment rod 54 is engaged with the aligning bearing 53A provided at the end of the lower arm 52A.
The core bar 54A of the alignment rod 54 is made of a light hollow cylindrical core bar, the outside diameter of which is about 8 mm. For example, a pipe made of a light metal such as aluminum, or a pipe made of a light fiber reinforced plastic is utilized for the core bar 54A. The outer circumference of the core bar 54A is coated with a resilient member 54B made of a foam resin such as sponge, the thickness of which is about 5 mm. The alignment rod 54 composed of the core bar 52A and the resilient member 54B, is light, so that the inertia of the aforementioned arms 52A, 52B can be reduced when they are oscillated.
Leaf springs 56 are respectively provided to the tip portions of the aforementioned upper arm 52b and lower arm 52A. The tip portions of the leaf springs 56 push the ends of the core bars 54B, 54A of the alignment rod 54. When sheets are aligned, the alignment rod 54 is oscillated by the arms 52B, 52A. When the alignment rod 54 reaches the side edge of sheets, it pushes the sheet edge by the force of the leaf spring 56 and the resilience of the resilient members 54B, 54A.
The aforementioned resilient member 54B comes into contact with the side of paper P discharged onto the bin with light pressure so that paper P can be pushed against the stopper wall 42D provided on the side of the bin 41 in order to align paper P. In the aforementioned aligning operation, the arms 52A, 52b slightly overrun the paper width, for example, it overruns by 2 -3 mm so that alignment of paper P can be positively performed. In this case, one side edge of paper P is contacted with the stopper wall 41D, and the other side edge is lightly contacted with the aforementioned soft resilient member 54B. Therefore, the side edge of paper P is not damaged.
When a paper is accommodated into the bin 41 in such a manner that it is conveyed onto a paper previously accommodated in the bin 41, and aligned by the aforementioned alignment rod 54, the alignment rod 54 hits the side edge of the bundle of papers in order to align them. In this time, the impact given by the alignment rod 54 can be absorbed and reduced since the aforementioned leaf spring 56 and resilient member 54B function as a buffer. Therefore, pulse motor M2 is not given an over load, and it never steps out.
An arc-shaped curved surface 520 protrudes from the aforementioned upper arm 52B, and intercepts an optical path of a photo-interrupter (a transmission type of photo-sensor), so that the home position of the upper arm 52B can be detected.
The oscillating angle of the aforementioned upper arm 52B is changed according the number of setting pulses of the aforementioned pulse motor M2 so that paper alignment can be conducted correspondingly to the size of discharged paper P.
A protruded shaft 521B is fixed to an oscillating base portion of the aforementioned upper arm 52B, and the upper arm 52B can be vertically oscillated around a pin 510 mounted on the rotating shaft 51. A roller 58 is rotatably engaged with the tip portion of the aforementioned protruded shaft 521B. The roller 58 slidably comes into contact with a groove cam 590 of a cam member 59B which is fixed to the aforementioned frame. Accordingly, when the upper arm 52B is oscillated around the rotating shaft 51, the roller 58 is also oscillated in the axial direction, slidably coming into contact with the aforementioned groove cam 590. In the same manner, the roller 58 is rotatably engaged with a protruded shaft 521A which is protruded into the oscillating base portion of the lower arm 52A, and the roller 58 is slidably contacted with the groove cam 590 of the cam member 59A and oscillated in the axial direction. When sheets P tacked on the bin 42 are aligned by the aforementioned oscillating motion, the side edges of the papers are pressed downward to be aligned.
FIG. 17 is a sectional view showing an oscillating state of the alignment rod 54.
In FIG. 17, the shape illustrated by a broken line shows a progress in which initial position A of the alignment rod 54 moves to final position F through intermediate positions B-E.
The aforementioned alignment rod 54 moves along an oscillating locus (illustrated by a one-dotted chain line) show in the plan view of FIG. 15, and at the same time moves along a three-dimensional locus composed of a horizontal and vertical locus, so that sheets P on the bin 41 are pressed downward to be aligned.
On the other hand, the bin 41 is oscillated as shown by a one-dotted chain line in FIG. 5 in order to insert papers P stacked on the bin 41 into the stapler. At the same time, all the bins 41 are moved forward and backward together with the bin moving section 40 by motor M1 correspondingly to the paper size. Accordingly, a large opening portion 41C is formed in the bin 41 as shown in FIG. 5 so that the alignment rod 54 can not interfere with the bin 41. Numeral 46 is a reinforcement member which closes the opening 41C of the bin 41 in order to prevent deformation of the bin 41 caused by the large opening 41C. This reinforcement member 46 is screwed to a side of the bin 41. At the same time, an arm 46A of the reinforcement member 46 closes a cut-out portion (a U-shaped groove) 41G through which the aforementioned slide member 44 is inserted, in order to prevent disconnection of the slide member 44 so that the slide member 44 can be positioned and fixed.
The vertical stopper wall 41D is integrally provided on one side of the aforementioned bin 41. An inner side surface of the stopper wall 41 is a bumping surface against which a side edge of paper P is bumped in order to align the paper. The bumping surface is formed into a step-shape having a plurality of protruded and cut-out portions. The protruded portions are contacted with one of the side edges of paper P, and the cut-out portions are separated from the aforementioned side edge of paper P so as to form gaps. Air in an air layer formed between papers in a bundle of papers stacked on the bin 41 by the oscillation of the aforementioned alignment rod 54, leaks to the outside through the aforementioned gaps formed by the cut-out portions. Accordingly, the following problem can be solved: the height of the stack of papers P on the bin 41 is increased, and successive paper P runs over the bumping surface and jumps out of the bin to cause a failure in paper alignment.
A paper holding device 60 is provided on an outer side of the aforementioned stopper wall 41D. A lever 61 is rotatably supported by a shaft 62 provided on the outer surface of the stopper wall 41D. A paper holding member 63 is provided at one of the ends of the lever 61. The other end of the lever 61 is pressed by a roller 72 which is pushed by a leaf spring and mounted on the tip of an arm 71 of a bin oscillating device 70. Since the lever 61 is pushed in the manner mentioned above, it is oscillated so as to press the upper surface of papers P stacked on the bin 41.
A base plate of the aforementioned bin oscillating device 70 is mounted on a common frame together with a base plate of a stapler 80. The base plate is moved and stopped at each bin by a lift not shown which is driven in the up and down direction on the aforementioned bin moving device 40, and the bundle of papers stacked on the bin 41, being pressed by the aforementioned paper holding member 63, are inserted into a stapling gap of the stapler 80 so that a staple 83 can be hit.
After the staple has been hit, the arm 71 is returned and the bin 41 is oscillated by a spring force and returned to the initial paper discharging position.
Next, a stapling operation conducted on a bundle of papers discharged onto the bin 41 will be explained as follows.
When the position of a document is determined on the platen glass of the image forming apparatus 1, there are two manners, one is a manner in which the document is set so that the center of the document can coincide with the center line of the image forming apparatus, and the other is a manner in which the document is set so that one side of the document can coincide with a reference line.
A stapling operation of a bundle of papers P which are discharged on the center line, will be explained referring to FIG. 18 and FIG. 19. FIG. 18 is a plan view showing a state of accommodation and alignment of papers performed on the bin 41. FIG. 19 is a plan view showing a state of a stapling operation performed while the bin 41 is oscillated.
(1) When the size of a paper P (a copy paper) discharged from the image forming apparatus 1 is set manually or automatically, the bin shift section 40 of the sorter is driven electrically, and when the bin has reached a predetermined position corresponding to the size of the aforementioned paper, the bin stops according to a signal sent from a position detecting sensor. Therefore, the bin is set in a waiting condition. The maximum movement amount of the bin movement section 40 is determined in such a manner that: the minimum width of paper (for example, B5 size, 257 mm) is subtracted from the maximum width of paper (for example, 17 inches); and the obtained value is divided by 2 (for example, 87.4 mm can be obtained). In this waiting position, the stopper wall 41D of the bin 41 is located in a position which is separated from a side edge of the width direction of paper P by distance δ (for example 10 mm).
(2) In the aforementioned condition paper P enters from the left in the drawing, and moves upward along the inclined surface of the uppermost bin 41. After that, paper P slides down by its dead weight and bumps against a front stopper 41S to be stopped.
(3) After paper P has been stopped, the alignment rod 54 is oscillated and pushes one side edge of paper P to move it toward the viewer's side by the distance of δ, so that the other side edge of paper P can be contacted with the stopper wall 41D. This distance δ is set to almost the same in the case of other sizes (for example, A4 size, B4 size and A3 size).
(4) Successively, the following paper P is discharged into the second bin 41 by the branch guide 36, and the aforementioned alignment rod 54 is oscillated and pushes the side edge of paper P in the same manner as described above, so that paper P is contacted with the stopper wall 41D to be aligned.
(5) In the same manner as described above, papers are successively stacked in the bins, the number of which corresponds to that of document sheets.
(6) When a counter of CPU control detects that a predetermined number of papers P have been accommodated in the uppermost 41, and when it is detected that an optical path has been opened which is formed between a light emitting element LED provided to the upper portion of the bin movement section 40 and a light receiving element PT r provided to the lower portion so as to detect the passing of the trailing end of a final paper P, the discharging operation to the first bin 41 is completed. (Refer to FIG. 1.)
(7) Immediately after it is detected that a paper discharging operation of the second bin 41 has been completed, or after a predetermined period of time has passed after the detection, the aforementioned uppermost bin 41 is oscillated by the aforementioned bin oscillating device 70, resisting a force of the spring 59. When a stapling signal is inputted into the stopped bin moving section 40, the paper holding member 63 presses the upper surface of the sheets stacked on the bin 41 in such a manner that: first, the aforementioned bin oscillating device 70 is driven and the arm 71 is oscillated; the roller 72 mounted on the tip pushes the aforementioned paper holding device 60; and further the roller 72 oscillates the lever 61 counterclockwise around the shaft 62.
(8) Successively, the roller 72 mounted on the tip of the arm 71, is oscillated around the slide member 44 (for example, θ=12°) so that the bin 41 is oscillated while the sheets in the bin 41 are being pressed.
(9) A sensor of the bin oscillating device 70 detects the oscillating position and the oscillation of the bin 41 is stopped.
(10) In this stop position, a rear corner portion of the bundle of papers is inserted into a stapling gap of the stapler 80, and then the stapler 80 is driven and a staple 83 is hit.
(11) After the stapling operation has been completed, the arm 71 is driven to be returned, so that the bin 41 is pushed by a spring force and returned to the initial position, and at the same time the paper holding member 63 is separated upward from the surface of the bundle of papers. In this manner, the bundle of papers 41 can be taken out from the bin 41.
(12) After the bundle of papers accommodated in the uppermost bin 41 have been stapled, a unit in which the stapler 80 and oscillating device 70 are integrally provided, is lowered by a lift, and almost simultaneously the bin 41 positioned below the uppermost bin is oscillated and a stapling operation is conducted in the same manner. In the mean time, a paper discharging operation is conducted in a bin 41 located further below, and the alignment rod is oscillated to align the sides of papers P.
(13) When all the bundles of papers have been stapled, the unit in which the bin oscillating device and stapler have been integrated, is returned to the uppermost bin position.
The aforementioned stapling operation has been conducted on a sorter in which papers are aligned under the condition that a center of the paper discharged from the image forming apparatus 1 coincides with the center line of the apparatus 1. However, it should be understood that the present invention is not limited to the specific embodiment. The present invention can be applied to a sorted in which paper alignment is conducted so that one side of a paper can coincide with a reference line.
As explained above, according to third embodiment of the present invention, the sheets accommodated on the bin are aligned in such a manner that the side edges of the sheets are pressed downward by the alignment rod which is oscillated in a manner of three dimensions. Therefore, even when curled papers can be positively pressed onto the reference wall surface, so that the sides of sheets can be orderly aligned, and the following stapling operations can be positively conducted. When sheets are aligned, the aforementioned alignment rod being pushed by the spring, presses the side edges of the bundle of papers, so that an impact load is not given to the pulse motor and the stepping out of the pulse motor can be avoided. Consequently, oscillation can be performed smoothly, and driving force can be effectively reduced.
In the case of a sorter in which a non-sort bin, which is also used for a paper discharging tray, is mounted on the uppermost portion of a plurality of bins, the sides of papers are aligned while the aforementioned alignment rod and supporting arm are being lowered. Accordingly, the alignment rod and supporting arm do not interfere and contact with the non-sort bin which are disposed in a small space, so that the total height of the sorter can be reduced and the apparatus can be made compact.
Referring to the drawings, the fourth embodiment to accomplish the second object of the present invention will be explained as follows.
FIG. 20 is a view showing the structure of a sorter connected with the image forming apparatus (for example, a copier) 1. FIG. 21 is a sectional view showing an essential portion of a sheet conveyance system. A sorter of the present invention is composed of a base 10, downward conveyance section 20, upward conveyance section 30, and bin moving section 40.
The base 10 comprises a caster 11, a connecting means 12 to connect with the image forming apparatus 1, a conveyance belt 13, conveyance rollers 14 composed of a drive roller 141, an idle roller 142 and a tension roller 143, pushing rollers 15A, 15B, 15C, 15D, a guide plate 19, and a drive means which will be described later, and the like. The base 10 is fixed on the floor.
A stay member 16 is fixed to the base (the intermediate conveyance section) 10 in a direction perpendicular to the surface of FIG. 20. Rack gear RG is fixed on the upper surface side of the stay member 16.
A stay member 16 is provided to the base frame (the horizontal conveyance section) 10 in the direction perpendicular to the surface of FIG. 1. A rack gear RG is fixed on the upper surface of the stay member 16.
On the other hand, rollers 17A, 17B used to move the frame are rotatably provided in the frame of the bin shift section 40. The aforementioned rollers 17A, 17B move on rails of the aforementioned base frame 10, wherein the rails are not illustrated in the drawing. Therefore, the frame of the bin shift section 10 can be moved in the direction perpendicular to the surface of the drawing. Motor M1 is provided inside the frame of the bin shift section 40. Motor M1 drives pinion gear PG through gears G1, G2. Since pinion gear PG meshes with rack gear RG fixed to the aforementioned stay 16, the frame of the bin shift section 40 is moved in the direction perpendicular to the surface of the drawing when motor M1 is rotated.
Numeral 18 is a roller which is provided on the shaft of the aforementioned pinion gear PG, and the roller 18 is slidably contacted with the aforementioned stay 16 to guide it.
FIG. 21 is a sectional view showing an essential portion of the sheet conveyance device.
A downward conveyance section 20 is connected with a paper discharge roller 2 and a paper discharge port 3 of the image forming apparatus 1, and discharged paper P is received by a guide plate 21 so that paper P can be conveyed downward. The downward conveyance section 20 includes a conveyance belt 22, rollers 233, 234 and press rollers 28A, 28B, 28C, 28D by which paper P is conveyed to a conveyance belt 13 provided in the aforementioned base 10. The aforementioned conveyance belt 22 is provided between a lower drive roller 231 and an upper idle roller 232, and intermediate rollers 233, 234 are provided inside the conveyance belt 22, and further a tension roller 225 is provided outside to give a tension to the conveyance belt 22. The aforementioned press rollers are mounted on a door 201 which can be freely opened and closed. The press rollers 28A, 28B, 28C which can be contacted with and separated from the aforementioned conveyance belt 22 are provided, and further the roller 28D is provided which presses the outer circumference of the aforementioned drive roller 231 through the conveyance belt 22 so that the conveyance belt 22 can be rotated to convey paper S.
The aforementioned door 201 is hinged to the lower portion of the case of the downward conveyance section 20 so that a jammed paper in the downward conveyance section 20 can be removed.
A paper discharge roller 24 and an intermediate tray 25 are provided which are used to discharge a previous paper in the image forming apparatus 1 when a jam is caused in an ADF and sorter branched from the aforementioned conveyance passage.
In the aforementioned intermediate tray 25, not only the aforementioned jammed paper but also special papers S1 are accommodated. Special paper P is defined as a paper, the size of which is smaller than the ordinary one (for example, B6 size, post card size, size of 5.5×8.5 inches, and the like), and further defined as a paper which is not suitable for conveyance in the sorter (for example, an OHP film, label paper, thin paper, and the like). The aforementioned special paper S1 is conveyed in the apparatus in such a manner that: according to a command sent from the image forming apparatus (for example, loading of a special cassette), special paper S1 is separated from the conveyance belt 22 by a branch means at the press roller 28C; and special paper S1 is conveyed by a paper discharge roller 24 composed of a drive roller 241 and an idle roller 242 along a guide plate 29, and discharged onto the intermediate tray 25.
Paper S2 which is required to be sorted, grouped and stapled, is advanced straight at the aforementioned branch point, conveyed being pinched by the conveyance belt 22 and the press roller 28D, conveyed to the base portion (the intermediate conveyance section) 10, and conveyed onto the conveyance belt 13 along the guide plate 19.
The aforementioned conveyance belt 13 is wrapped around the drive roller 141, idle roller 142, and tension roller 143, and slid on the support plate 144. The press rollers 13A, 13B, 13C, 13D are contacted with the upper surface of the conveyance belt 13 with pressure so that they can be rotated idly, and paper S2 is pinched by the conveyance belt 13 and press rollers and conveyed to the upward conveyance section 30.
In the upward conveyance section 30, rollers 33 and 32 are rotatably provided to the upper and lower portion the support frame, and a plurality of endless conveyance belts 31 are provided between the two rollers. A plurality of rollers 31 corresponding to the entrance of the bin are provided inside the conveyance belt 31. A plurality of conveyance rollers 35 are provided outside the conveyance belt 31 in such a manner that they are opposed to the rollers 34, so that the conveyance rollers 35 can be rotated idly by the conveyance belt 31.
A branch guide 36 is provided and oscillated between the conveyance rollers 35 at the entrance of each bin. This branch guide 36 is rotatably supported by a shaft 37 mounted on the aforementioned support frame, and oscillated by a lever and solenoid (not shown) installed at the end of the shaft 37. Accordingly, when the branch guide 36 is rotated clockwise, a lower claw portion of the branch guide 36 is crossed with the paper conveyance passage composed of the conveyance belt 31 and the conveyance roller 35 so that the upward advance of a paper is interrupted by the claw to receive the paper. When paper S2 is conveyed under the condition described above, paper S2 is curved along the inner curved surface of the branch guide 36 and received by the bin 41.
That is paper S2 is conveyed as follows:
Paper S2 (illustrated by a one-dotted chain line in the drawing) is conveyed into the upward conveyance section 30 at a high speed, conveyed upward being pinched by the conveyance belt 31 and the conveyance roller 35, curved to the right by the claw 36 (the second one from the bottom) which is oscillated clockwise by a solenoid not shown, and conveyed above a vertical stopper wall 41S of the bin 41. After that, paper S2 ascends along the inclined surface of the bin 41. After the trailing end of paper S2 has passed through the upper position of the aforementioned stopper 41S, paper S2 begins to descend, and slides down on the surface of the bin 41 by the action of gravity. Finally, the trailing end of paper S2 collides against the stopper wall 41S, and paper S2 is stopped.
Even when the trailing end of paper S2 is curled up, the curling can be prevented by the claw 41B provided on the top of the bin 41. Accordingly, paper S2 comes into contact with the stopper wall 41S by the action of gravity to be aligned.
A deep bottom type of non-sort tray 49 is provided above the uppermost bin 41 in a plurality of bins (20 steps of sort bins shown in FIG. 1). The non-sort tray 49 is a tray to accommodate non-sorted papers S3 on which images have been formed. On the non-sort tray, 200-300 sheets of papers can be stacked. Command and release of sorting and grouping can be selected through an operation panel provided on the image forming apparatus side.
On the other hand, in the case of a sorter provided with a stapler, in order to insert papers S2 into the stapler, all the bins 41 are advanced and withdrawn by motor M1 together with the bin moving section 40 correspondingly to the paper size, and further oscillated around a fixed shaft 43.
On the other hand, on a portion of the upward conveyance section 30, is mounted an alignment device 50 which aligns the side edge of paper S2 discharged onto the bin 41 from the image forming apparatus 1.
FIG. 22 is a sectional front view showing a drive means of the aforementioned paper conveyance system, and FIG. 23 is a plan view of the drive system.
A mechanism of the driving system is installed on the fur side of the aforementioned base 10 of the sorter. A rotary encoder is provided inside main motor (for example, a DC motor) M01 which is fixed to the base 10, and the rotating speed of this motor is adjustable. A reduction gear box is integrally connected with the aforementioned motor M01, and gear G01 is integrally mounted on the drive shaft 101. Gear G01 is engaged with spur gear G02 which is rotatably supported by an intermediate shaft 102. A bevel gear portion of the aforementioned gear G02 is engaged with bevel gear G04 which is rotatably supported by the second intermediate shaft making a right angle with the first intermediate shaft 102. Accordingly, the direction of power transmission can be deflected by a right angle.
Bevel gear G04 is integrally connected with 3 pulleys P1, P2, P3. Pulley P1 rotates pulley P4 through belt B1. A drive roller 231 is coaxially provided to pulley P4 to be rotated integrally. When the drive roller 231 is rotated, the conveyance belt 22 is driven. Linear velocity V2 (for example, 640 mm/sec) of the conveyance belt 22 is set to be higher than fixed paper discharging speed V1 (for example, 300 mm/sec) in the fixing unit 4 of the image forming apparatus 1 (V2>V1).
The leading edge of paper S discharged from the fixing unit 4 and paper discharging roller 2 at linear speed V1, is pinched by the conveyance belt 22 and press rollers 28A-28D and conveyed at linear speed V2. While the trailing edge of paper S is being strongly pinched by the aforementioned fixing unit 4, the leading edge of paper S slips and paper S is conveyed at linear speed V1. After the trailing edge of paper S has passed through the fixing unit 4, paper S is conveyed to the intermediate conveyance section 10 at linear speed V2 which is the same as that of the conveyance belt 22.
On the other hand, the aforementioned pulley P4 rotates pulley P5 through belt B2 so that a drive roller 241 of a paper discharging roller 24 is rotated since pulley P5 is integrated with the drive roller 241. Circumferential speed V4 of the aforementioned paper discharging roller 241 is set to be a little higher than linear conveyance speed V2 of the aforementioned conveyance belt 22 (for example, it is set to 650 mm/sec), or to be the same as linear conveyance speed V2. Paper S1 which is branched from the conveyance belt 22 and press roller 28C at linear speed V4, is discharged onto the intermediate tray 25.
The aforementioned pulley P2 rotates pulley P6 through belt B3.
A drive roller 141 is integrally provided to a rotating shaft 104 on which pulley P6 is mounted. The aforementioned conveyance belt 13 by which the drive roller 141 is wrapped, is rotated at linear speed V3 (for example, 740 mm/sec). Linear speed V3 of the conveyance belt 13 in the intermediate conveyance section 10, is set higher than linear speed V2 of the conveyance belt 22 in the aforementioned introducing section 20 (V3>V2).
On the other hand, the aforementioned pulley P3 rotates pulley P7 through belt B4. Pulley P7 and pulley P8 provided on the same shaft, rotate pulley P9 through belt B5. Pulley P9 and bevel gear G05 provided on the same shaft, rotate bevel gear G07 mounted on the shaft of the drive roller 32, through a bevel gear and spur gear portion of gear G05 provided on the intermediate shaft and through a spur gear and bevel gear portion of gear G06 provided on another intermediate shaft. When the drive roller 32 is rotated, the conveyance belt 31 is rotated at the same speed as linear speed V3 of the conveyance belt 13 in the intermediate conveyance section, or at a speed a little higher than that. Paper S2 is ascended and deflected to be accommodated in a predetermined bin 41 at the aforementioned linear speed of the conveyance belt 31.
A discharging speed of a sheet which is accommodated in the bin 41, can be adjusted stepwise. FIG. 24 is a block diagram of the sheet conveyance control means.
When a size of recording paper S is set manually or automatically by an automatic paper feeding mechanism in accordance with the document size, the rotating speed of DC motor M01 is automatically selected according to a signal of the paper size. For example, a large-sized paper S2B is selected for A3 size and B4 size, paper S2b is discharged onto the bin 41 through the downward conveyance section (the introducing section) 20, the intermediate conveyance section 10, and the upward conveyance section 30 at a high speed of linear speed V3 (for example 740 mm/sec) of the aforementioned conveyance means. In this case, paper S2B is discharged at a high speed by a nip conveyance force between the conveyance belt 31 and the conveyance roller 35, and slid and ascended upward resisting a frictional force caused by the upper surface of a stacked paper. After the trailing end of paper S2B has passed through the upper position of the stopper wall 41S of the bin 41, paper S2B is descended, and slid on the surface of the stacked paper on the bin by the action of gravity. Finally, the trailing end of paper S2B collides with the stopper wall 41S, and paper S2B is stopped.
When it has been judged that paper S2 is of a small size (for example, B5 size or A4 size), the rotating speed of the aforementioned DC motor M01 is controlled by a control section and a rotary encoder provided inside motor M01, and the rotating speed is reduced. Due to the foregoing, linear speed V2 of the aforementioned conveyance means is lowered to 600-700 mm/sec. At the same time, linear speed V2 of the conveyance belt 22 and linear speed V4 of the paper discharge roller 24 are also lowered proportionally to the rotating speed of motor M01 at the same lowering rate as that of the aforementioned linear speed V3.
In the aforementioned embodiment, sheet sizes are classified into two so as to be judged, one is a large size and the other is a small size, and the sheet conveyance speed is varied into two steps. However, it is possible to classify the sheet sizes into not less than 3 sizes and to change over the sheet conveyance speed into not less than 3 steps.
As explained above, according to the fourth embodiment to accomplish the second object of the present invention, various sizes of sheets discharged from the image forming apparatus are discharged onto the bins of the sorter an an optimum discharging speed, so that problems such as misalignment and jam can be solved. Especially in the sorter in which a stapling and punching operation are conducted after a sorting process, paper alignment is important. Therefore, sheets stacked in the bins are orderly accommodated by the sheet conveyance speed control of the present invention so as to be processed later.
In the aforementioned first to fourth embodiment, the rib and stopper wall can be formed into the following shapes. FIG. 26 is a perspective view of the bin 41 taken from the bottom side. A plurality of ribs 41E (inverse-triangle-shaped plates shown in the drawing) are integrally formed on the bottom side of each bin. The aforementioned ribs 41E are formed on the bottom side of a gently curved surface which connects a lower stack surface 411 having a gentle inclination angle with an intermediate stack surface 412 having a sharp inclination angle.
On the other hand, a space formed between an upper portion of the stopper wall 41S and claw 41B, and the guide plate 48 supporting the upper bin 41, is used for an opening through which sheets are conveyed. Therefore, the distance between the upper and lower bin close to the sheet conveyance section is sufficiently longer than the maximum stack height of the sheets. On the other hand, the distance between the immediate portion stack surfaces 412 of each bin 41 is set to be slightly longer than the maximum stack height of the sheets in order to make the sorter compact.
The aforementioned ribs 41E are disposed between a position close to the aforementioned sheet conveyance opening and the intermediate portion stack surface 412 in such a manner that: a distance between the protruded portion of the rib 41E provided on the bottom surface of the upper bin 41 and the curved surface 414 of the upper surface of the lower bin 41 can be approximately the same as the distance between the aforementioned intermediate stack surfaces 412.
A lower surface 41EA on which the aforementioned ribs 41E are formed, serves as a guide surface used when paper P is conveyed, and a right inclined surface 41EB serves as a guide surface used when paper P is reversed in the process of alignment.
Since the ribs are formed in the manner mentioned above, papers P which are introduced through the sheet conveyance opening, are regulated by the aforementioned ribs 41E so that the conveyance direction can be stabilized and a predetermined number of papers can be stably ensured in the stack.
The aforementioned plurality of stopper walls 41S are utilized for aligning the trailing ends of papers P, and it is preferable that papers of all sizes are contacted with a left end portion of the bin 41 shown in the drawing. However, in the case of a sorter in which the distances between the bins 41 are maintained minimum and the bins 41 are oscillated for stapling, an upper end portion of the stopper wall 41S sometimes contacts with collides against a bottom portion of the upper bin 41.
In order to avoid the interference and collision between the upper and lower bin, a portion on the vertical wall having the stopper wall 41S is cut out correspondingly to a portion in which the vertical wall surface interferes with the lower bin 41 (portion A in FIG. 26).
An auxiliary reference plate 47 is integrally fixed on the vertical surface of the guide plate 48 on which the rear end bottom surface the the bin 41 is provided, correspondingly to a position in which the aforementioned cut-out portion A of the bin 41 is formed. In order to make up for the stopper wall 41S which has been cut out, the auxiliary reference plate 47 is provided with three stopper walls 47S of the same shape. A curved claw 47B is protruded from the upper end on the vertical wall of the stopper wall 47S, and the shape of the claw 47B is the same as that of the aforementioned claw 41B. Under the condition that the bin 41 is closely contacted with the vertical surface 48A of the guide plate 48 being pushed by the spring 59, the aforementioned stopper wall 41S and 47S are disposed on the same surface to form a reference surface against which a trailing end of paper P collides.
Further, the shapes and heights of the claw portions 41B and 47B become the same. When the bin 41 is oscillated by a bin oscillating means 70 which will be described later, a bundle of papers are oscillated to a stapling position while the trailing ends of papers stacked on the bin 41 is being contacted with the stopper wall 41S on the bin. However, the stopper wall 47S provided on the auxiliary reference plate 47 fixed on the guide plate 48, is left in a fixed position. Consequently, when the upper bin 41 is oscillated, the stopper wall 47S of the lower bin never interferes with the bottom portion of the upper bin 41.
FIG. 27 is a plan view showing another embodiment of the sorter according to the present invention. On a vertical wall of the bin 41, three stopper walls 41S are provided, two of them are located close to the center and one of them is located on this side in the drawing, and positioning is performed in such a manner that the trailing end of paper P is bumped against the stopper walls. On a portion of the vertical stopper wall except for the portion in which the stopper walls 41S are formed, two cut-out portions A are formed. On a vertical surface of the guide plate 48, are fixed two auxiliary reference plates 47 having the stopper wall 47S. As described above, when cut-out portion A is provided, it is effective for reducing the distance between the bins, and at the same time weight of the bin can be reduced.
According to the shape of the stopper wall explained above, when a large number of sheets are conveyed into a bin of a sorter, a bundle of sheets can be positively aligned, and further the distance between the bins can be minimized so that the number of sheets to be accommodated can be increased. When the distance between the bins is minimized, the total height of the sorter can be reduced, so that it is possible to make the apparatus compact. Especially in the case of a sorter provided with a stapler, when the bins are oscillated to the stapling position, the upper and lower bin do not interfere with each other, so that bin oscillation can be smoothly performed. When a portion of the stopper wall, vertical wall and paper stack surface of the bin are removed, weight of the bin can be reduced and inertia of the bin can be reduced in the bin oscillation process. Consequently, the bin stop position can be stabilized, and drive force can be reduced. Further, the drive force transmitting means can be effectively simplified.
Further, In the aforementioned first to fourth embodiment, the core bar 54A of the aforementioned alignment rod 54 is made of a light cylindrical hollow member such as a light alloy pipe (for example, an aluminum alloy pipe) and a light fiber reinforced plastic pipe. The outer circumferential surface (the diameter of which is about 8 mm) of the core bar 54A is coated with a resilient member 54B composed of a foaming resin member such as sponge. The alignment rod 54 composed of the aforementioned core bar 54A and the resilient member 54B, is light, so that inertia can be reduced when the aforementioned arms 52A, 52B are oscillated. | A sheet sorting machine for sorting plural sheets to plural groups and stapling the sheets by the group. The sheet sorting machine has a sorting assembly to convey the sheets to the plural bins by the group; a positioning member to true up the sheets to a setting position in each of the bins; a member to fix the sheets in the bins; oscillator to move the bins, holding the sheets at the setting position in the bins, to a stapling position; and stapler to staple the sheets at the stapling position; in which the fixing member fixes the sheets before the oscillator sets the sheets to the stapling position. | 1 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 14/718,422, filed on May 21, 2015, which is a continuation of U.S. application Ser. No. 13/778,426, filed on Feb. 27, 2013, now issued as U.S. Pat. No. 9,061,109, which is a continuation of U.S. application Ser. No. 12/804,506, filed on Jul. 22, 2010, now issued as U.S. Pat. No. 8,463,364, which claims priority on U.S. Provisional Application Ser. No. 61/271,587, filed on Jul. 22, 2009, the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] Drawing blood and administering intravenous medication using medical devices including but not limited to catheters are common medical procedures, but conventional methods to perform these procedures have several limitations. First a vein must be found. Conventional methods of locating an appropriate vein or artery include restricting the blood supply to the location of the body so that the blood pressure in that area is greater, which results in the patient's veins becoming more visible. This is often accomplished by the use of a temporary tourniquet, which can result in extreme discomfort to the patient. Even after the temporary tourniquet is applied and certain veins are exposed, a medical professional may still not be able to find an appropriate vein. This problem can occur more readily in elderly patients and patients with low blood pressure. Thus, there is a need for a non-invasive method for locating veins.
SUMMARY OF THE INVENTION
[0003] The present invention is directed towards a portable hand-held medical apparatus that uses infrared light to detect veins beneath the skin, then illuminating the position of the veins on the skin surface directly above the veins using visible light. When the apparatus is held a distance above the outer surface of the skin, veins appear vastly different than the surrounding tissue, and veins that are otherwise undetectable because of their depth in the tissue are safely located and mapped on the patient's skin. Vein's will be accessed more readily and with greater confidence and as such, venipuctures will go more smoothly while vasculature shows up clearly on the skin's surface, making it easy to select the best vein to collect a blood sample from or administer medications to. Qualified medical personnel can observe the displayed vasculature to assist them in finding a vein of the right size and position for venipuncture.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a perspective view of the apparatus of the present invention.
[0005] FIG. 2 is a perspective view of a charging cradle for the apparatus of FIG. 1 .
[0006] FIG. 3 is a front view of the apparatus of FIG. 1 , while being charged in the cradle of FIG. 2 .
[0007] FIG. 4 is a perspective view of the apparatus of FIG. 1 being charged in the cradle of FIG. 2 .
[0008] FIG. 5 is a side perspective view of the apparatus of FIG. 1 , highlighting the buttons and LCD screen of the device of FIG. 1 .
[0009] FIG. 6 is a bottom view of the apparatus of FIG. 1 .
[0010] FIG. 7 is an image of a health care professional utilizing the apparatus of FIG. 1 to enhance the vein image of veins in a patient's arm.
[0011] FIG. 8 is a Figure illustrating proper angling of the apparatus when being used to enhance the vein image of veins in a patient's arm.
[0012] FIG. 9 is a Figure illustrating proper centering of the apparatus when being used to enhance the vein image of veins in a patient's arm.
[0013] FIG. 10 is a perspective view of the apparatus of FIG. 1 , with the battery cover removed to show the battery compartment.
[0014] FIG. 11 is a perspective view of the apparatus showing removal of the battery cover.
[0015] FIG. 12 is a perspective view of the apparatus with the battery cover removed, exposing the battery when properly installed in the battery compartment.
[0016] FIG. 13 is a perspective view of battery of the apparatus.
[0017] FIG. 14 is a series of images identifying different indications the LCD display will provide for different battery power levels.
[0018] FIG. 14A illustrates a Low Battery message displayed on the LCD of the device.
[0019] FIG. 15 is a screen shot of the LCD start screen.
[0020] FIG. 15A is a screen shot of the LCD when utilized for making configuration setting changes.
[0021] FIG. 15B shows all of the LCD button icons and their functionality.
[0022] FIG. 16 is a series of screen shots of the LCD display used for modifying the default Vein Display Setting.
[0023] FIG. 17 is a series of screen shots of the LCD display illustrating changing of the Display Time-out interval.
[0024] FIG. 18 is a screen shot illustrating how to change the Backlight Intensity of the apparatus.
[0025] FIG. 19 is a screen shot of the LCD screen used for changing the speaker volume of the apparatus.
[0026] FIG. 20 is a series of screen shots showing the steps for labeling of the apparatus according to a user's preference.
[0027] FIG. 20A is a series of screen shots showing use of up/down arrows for character selection.
[0028] FIG. 21 is a screen shot illustrating how to change or review the language utilized on the apparatus.
[0029] FIG. 22 is a screen shot illustrating how to reset all of the settings for the apparatus back to the factory default settings.
[0030] FIG. 23 is a perspective view illustrating plugging a USB cable into the back of the apparatus to communicate with a PC, and a screen shot illustrating the LCD screen of the device schematically illustrating the connection.
[0031] FIG. 24 is a screen shot as it would appear on the PC of FIG. 23 when looking for the apparatus.
[0032] FIG. 25 is a screen shot as it would appear on the PC after the apparatus was detected, and the software running on the PC was checking to see if the apparatus software was current or needed to be updated.
[0033] FIG. 26 is a screen shot as it would appear on the PC, when an apparatus is not detected by the PC.
[0034] FIG. 27 is a screen shot illustrating the capability of naming the apparatus or changing the language, and doing so from the PC.
[0035] FIG. 28 is a series of screen shots of the PC illustrating the steps in which the software of an apparatus is updated.
[0036] FIG. 29 illustrates a cradle pack and mounting hardware for use in a medical environment utilizing a series of vein enhancing apparatuses.
[0037] FIG. 30 is an exploded view of the apparatus of the present invention.
[0038] FIG. 31 shows a bottom perspective view of the bottom section of the housing.
[0039] FIG. 32 shows a top perspective view of the bottom section of the housing.
[0040] FIG. 33 is a top view of the bottom section of the housing.
[0041] FIG. 34 is a cross-sectional view of the bottom section of the housing.
[0042] FIG. 35 is a bottom view of the bottom section of the housing.
[0043] FIG. 36 is an end view of the bottom section of the housing.
[0044] FIG. 37 is a top view of the top section of the housing.
[0045] FIG. 38 is a side view of the top section of the housing.
[0046] FIG. 39 is a bottom view of the top section of the housing.
[0047] FIG. 39A is a cross sectional view through the apparatus of FIG. 39 .
[0048] FIG. 40 is a first section cut through the top section of the housing.
[0049] FIG. 41 is a second cross-section through the bottom section of the housing.
[0050] FIG. 42 is an exploded view of the photodiode assembly.
[0051] FIG. 42A is a reverse perspective view of the photodiode board in the exploded view of FIG. 42 .
[0052] FIG. 43 is a top view of the photodiode assembly.
[0053] FIG. 44 is an bottom view of the photodiode engine.
[0054] FIG. 45 shows a perspective view of the bottom section of the housing with a portion of the photodiode assembly mounted inside the cavity of the bottom section of the housing.
[0055] FIG. 46 is a bottom view of the portable apparatus of the present invention.
[0056] FIG. 47 is a view of the inside of the battery cover.
[0057] FIG. 47A is a view of the outside of the battery cover.
[0058] FIGS. 48A-D is a assembly level block/schematic diagram of the present invention
[0059] FIGS. 49A-C is an additional assembly level block diagram of the present invention.
[0060] FIGS. 50A-D is a schematic of a circuit diagram of the user interface board.
[0061] FIGS. 51A-B is a schematic of a circuit diagram of the photodiode board connection.
[0062] FIG. 52 is a schematic of a circuit diagram of the USB chip.
[0063] FIGS. 53A-E is a schematic of a circuit diagram of the photodiode board.
[0064] FIG. 54 is a schematic of a circuit diagram of the battery connector board.
[0065] FIGS. 55A-E is a schematic of a circuit diagram of the visible laser drive.
[0066] FIGS. 56A-D is a schematic of a circuit diagram of the laser safety feature of the present invention
[0067] FIGS. 57A-D is an additional schematic of a circuit diagram of the photodiode engine.
[0068] FIGS. 58A-E is a schematic of a circuit diagram of the speaker of the present invention.
[0069] FIGS. 59A-G is an additional schematic of a circuit diagram of the photodiode engine.
[0070] FIGS. 60A-F is an additional schematic of a circuit diagram of the photodiode assembly.
[0071] FIGS. 61A-E is a schematic of a circuit diagram of a microcontroller of the present invention.
[0072] FIGS. 62A-D is a schematic of a circuit diagram of the power supply of the present invention.
[0073] FIGS. 63A-B is an additional schematic of a circuit diagram of the power supply and its peripheral connections.
[0074] FIGS. 64A-E is a schematic of a circuit diagram of the battery management system.
[0075] FIGS. 65A-D a schematic of a circuit diagram of the photodiode engine.
[0076] FIGS. 66A-E illustrates the graphical or symbolic information that may be projected onto a patient other than just vein imaging.
[0077] FIG. 67A illustrates a first arrangement of optical detectors that may be used for the apparatus.
[0078] FIG. 67B schematically illustrates an alternative arrangement of optical detectors.
[0079] FIG. 67C illustrates a second alternative arrangement for the optical detectors.
[0080] FIG. 68 illustrates one mechanical arrangement for the scanning mirrors.
[0081] FIG. 69 illustrates smoothing of the edges of the scanning mirrors to improve the high resolution images at smooth video rates.
[0082] FIG. 70 illustrates the apparatus illuminating on the skin of a patient, a coated needle that has been inserted beneath the patient's skin.
[0083] FIG. 71A illustrates a typical return signal collected from photodiodes of the current invention, with local peaks corresponding to vein locations.
[0084] FIG. 71B represents the same signal of FIG. 71A after differentiation.
[0085] FIG. 72 illustrates a few consecutive scan lines crossing a single vein.
[0086] FIG. 73 is a graph showing the output power versus the forward current for a laser, to illustrate an inflection point.
DETAILED DESCRIPTION OF THE INVENTION
[0087] The present invention is directed to an apparatus 10 ( FIG. 1 ) that is an opto-electronic device that assists medical practitioners by locating veins and then projecting an image of those veins directly on a patient's skin. The apparatus may be portable, hand held, and battery powered. However in an alternative embodiment an external power supply may be used to power the apparatus. The apparatus operates by using infrared light to detect veins beneath the skin, and then illuminates the position of the veins on the skin surface directly above the veins using visible light. The apparatus 10 may be battery powered, and rechargeable using a cradle 5 ( FIG. 2 ), and may generally be stored therein ( FIGS. 3-4 ).
[0088] The apparatus 10 generally comprises a housing 11 , internal circuitry 12 , keypad 13 , display 14 , scanner assembly 15 , and battery pack 16 . The housing 11 may generally comprise a top section 17 and bottom section 18 as shown in FIG. 30 . Although a specific shape for the housing and the top and bottom sections are shown it will be appreciated that this is merely a representative example and other configurations are intended to be included in the invention. The function of the housing 11 is to for example provide a location to mount the internal circuitry 12 , keypad 13 , display 14 , scanner assembly 15 , and battery 16 . A general embodiment of the housing will be disclosed, but it will be generally understood that modifications to the housing to accommodate different internal circuitry, keypad, display, laser assembly, and battery are within the scope of this invention. In addition, if other features are desired the housing may be modified to include those features.
[0089] The housing 11 may be comprised generally of a top section 17 and a bottom section 18 . FIGS. 31 and 32 show a representation of one embodiment of the bottom housing section 18 of the housing 11 , in perspective views, and which are detailed in FIGS. 33-36 . As seen in FIGS. 31 and 32 , the bottom housing section 18 generally comprises a left sidewall 19 and a right those walls 20 , which are connected by a front wall 22 and rear wall 23 . The exterior surfaces of those walls, which may be handled by the user, are seen in FIG. 35 , while the interior surfaces of those walls, which may receive the electronic circuitry and other components, are visible in FIG. 33 .
[0090] The walls 19 - 22 may each be angled, and may be so angled simply for aesthetic reasons, or for better handling by a user, or the angling (draft) may be the result of the manufacturing process used to create the housing bottom section 18 , possibly being a casting process, a forging process, or a plastic injection molding process. However, the walls 19 - 22 need not be so angled, and the housing bottom section 18 may also be manufactured using any other suitable manufacturing process or processes, including, but not limited to, machining of the part. One end of the angled walls 19 - 22 may terminate in a generally flat bottom wall 23 , to create an internal cavity 24 . The generally flat bottom wall 23 may transition, using transition wall 25 , into another generally flat wall 23 A. Wall 23 A may be interrupted by a series of internal walls ( 26 A, 26 B, 26 C, and 26 D) extending therefrom and an internal top wall 26 E connecting those internal side walls, to form a compartment that may house the battery 16 . The other end of the angled walls 19 - 22 may terminate in an edge 27 . Edge 27 , at front wall 21 and in the nearby regions of sidewalls 19 and 20 , may be generally planar, but may transition into edge 27 A, which serves as a transition to generally planar edge 27 B that begins at rear wall 22 . Each of the edges 27 , 27 A, and 27 B of the housing bottom section 18 may have a step for receiving a corresponding protruding flange of the housing top section 17 , when they are joined during assembly of the apparatus 10 .
[0091] In one embodiment, the front wall 21 and sidewalls 19 and 20 of the housing bottom section 18 may have extending up towards the plane of the edge 27 , one or more cylindrical members—a boss 107 , which is adapted to receive mounting screws 106 , and may include the use of threaded inserts for mounting of the housing top section 17 to the housing bottom section 18 . It will be appreciated that other mounting means may be used, including, but not limited to, the use of a snap closure, or a post and recess combination with a friction fit therebetween.
[0092] The bottom wall 23 of housing bottom section 18 may be provided with two orifices 28 , and 29 . On the outside surface of bottom wall 23 there may be one or more annular recesses 28 A and 29 A, being concentric to orifices 28 and 29 , respectfully, each of which may be used to receive a lens 90 ( FIGS. 6 and 10 ).
[0093] Protruding inward from the inside of bottom wall 23 may be cylindrical protrusions 31 , and 32 . Protrusions 31 and 32 may be concentric with orifices 28 and 29 , respectfully, and may be adapted to receive a portion of the photodiode masks 66 and 67 of the scanner assembly 15 , which are discussed later.
[0094] Mounted inside the battery compartment formed by walls 26 A- 26 E may be the battery pack 16 . The battery pack 16 ( FIG. 13 ) can be any of a variety of models known in the art, but in a preferred embodiment, it may be rectangular to fit inside the compartment formed by walls 26 A- 26 E. One end 16 A of the battery pack 16 may be adapted to be received by the power connection 95 on the main circuit board ( FIG. 30 ). The battery pack 16 may be secured in the battery compartment by a battery cover 96 which attaches to the bottom section 18 of housing 11 . The battery cover 96 may attach to the bottom section of the housing 18 in a variety of ways, such as by clips or screws. As seen in FIG. 47 , the battery cover 96 may be secured by having a pair of flanges 96 A extending therefrom be received in a pair of slots 34 in the bottom section 18 of housing 11 . FIGS. 62-64 are schematics of circuit diagrams which demonstrate how the battery pack is connected to the internal circuitry 12 , the scanner assembly 15 , and remaining electrical components of the invention.
[0095] FIGS. 37-41 show a representation of one embodiment of the top section 17 of the housing 11 . The housing top section 17 may be formed similar to the housing bottom section 18 , and thus may have a top wall 81 from which extends, generally at an angle, a left sidewall 83 and right sidewall 84 , and a front wall 85 and rear wall 86 . The front wall 85 and rear wall 86 may extend from the left sidewall 83 and right sidewall 84 , respectively, creating an internal cavity 87 . FIG. 37 shows the outer surfaces of those walls, while FIG. 39 shows the inner surfaces of those walls. The walls 83 - 86 extend out to a generally planar edge 82 , which may have a peripheral flange protruding therefrom to mate with the recess of the housing bottom section 18 . In one embodiment, housing top section 17 may have extending down from top wall 81 and walls 83 - 86 , towards the plane of the edge 82 , one or more cylindrical members 108 , which are adapted to receive mounting screws 106 , and may include use of threaded inserts. The cylindrical members 108 of the housing top section 17 may be positioned to be in line with the corresponding members 107 of the housing bottom section 18 to be secured thereto during assembly of the scanner 10 .
[0096] The outer surface of the top wall 81 of the housing top section 17 may have a step down into a flat recessed region 81 A having an edge periphery 81 P. That flat recessed region 81 A may comprise of an opening 91 through to the inside surface, which may be a rectangular opening, and a plurality of shaped orifices 93 A, 93 B, and 93 C. The rectangular-shaped opening 91 may be sized and otherwise adapted to receive the display 14 , which is discussed in more detail hereinafter. The flat recessed region 81 A of top wall 81 may receive a display guard 92 ( FIG. 30 ), to provide a barrier between the display 14 and the outside environment. The plurality of shaped orifices 93 , which may also be correspondingly found in the display guard 92 , are adapted to receive a plurality of buttons 77 or other activating means which may be mounted directly under the top plate 81 of the housing top section 17 . In a preferred embodiment, there are three buttons—a first display button 110 , a second display button 111 , and a power button 112 . Buttons 110 - 112 may be any shape practicable, but in a preferred embodiment, display buttons 110 and 111 are elliptical, and button 112 is circular. (Note that a fourth button 113 protruding from the side of the housing, as seen in FIGS. 5 and 30 , may also be used to power the apparatus up or down, as well as accomplish other functions as well).
[0097] Alternatively, other means of user input, such as touch screen, touch pad, track ball, joystick or voice commands may replace or augment the buttons.
[0098] The internal circuitry 12 is illustrated in FIGS. 48-65 , and can include a main circuit board 43 , a user interface board 44 , USB chip 46 , and speaker 47 . In one embodiment, the main circuit board 43 contains at least two orifices 48 and 49 which are adapted to receive mounting member 50 and mounting member 51 . Mounting members 50 and 51 may be used to secure the main circuit board 43 to the heat sink 52 . Mounting members 50 and 51 may be screws, or pins or any similar type of member used to secure internal circuitry known in the art. FIG. 48 is a schematic of a circuit diagram of the main circuit board 43 and how it connects to the remaining components of the present invention.
[0099] As seen in FIG. 30 , heat sink 52 generally comprises a left sidewall 99 , and right sidewall 100 , and a front sidewall 104 extending between the left and right sidewall. In a preferred embodiment heat sink 52 may also contain a middle bridge 101 which connects the left sidewall 99 with the right sidewall 100 . Extending from the middle bridge and curving downwards is a hook member 102 . The hook member has an internal cavity 103 , which is adapted to receive the USB chip 46 . On the front sidewall 104 , and left and right sidewalls 99 and 100 , there may be cylindrical members 105 that are adapted to receive mounting screws 106 , and may include the use of threaded inserts. Mounting members 40 may be used to mount the scanner assembly 15 . In one embodiment, mounting members 40 may be screws. It will be appreciated that the photodiode assembly may be mounted by other means.
[0100] The heat sink capabilities might be enhanced by a fan or blower arranged in a way that would direct the air flow onto the heat sink and out of the housing. Additionally, a thermodynamic or thermoelectric heat pump may be employed between the heat-dissipating portions of the heat sink, to facilitate heat exchange. In a preferred embodiment, a heat shield 80 is mounted onto the top surface of the user interface board 44 .
[0101] Preferably being directly connected the main circuit board 43 , is the user interface board 44 . FIG. 50 is a schematic of a circuit diagram of the user interface board. The user interface board 44 contains the firmware which sends a graphic user interface to the display 14 , and stores the user's preferences. In one embodiment the interface board 44 is directly mounted to the top surface of the main circuit board. In one embodiment, the display 14 is directly mounted to the user interface board 44 , and may be a Liquid Crystal Display (LCD). It will be appreciated to those skilled in the an that an Organic Light Emitting Diode display (OLED) could work equally well. Alternatively, other means of information delivery may be used, such as lamp or LED indicators and audible cues. Some of the information that may be delivered to the user, other than the projection of vein images onto a patient's arm, may be visual cues also being projected on the patient's arm alongside the vein images, visual cues regarding additional information concerning the veins.
[0102] Mounted to the user interface board may be a keypad 13 . Keypad 13 , as noted previously, may be comprised of a plurality of control means which may include, but is not limited to, a plurality of buttons 77 . In a preferred embodiment, there may be three buttons used for controlling the apparatus—buttons 110 - 112 . Each of these buttons may have a first end 78 and a second end 79 . The first ends 78 of the plurality of buttons is adapted to be exposed through corresponding openings in the housing top section 17 , where they may be toggled by the user. The second end 79 of the buttons is adapted to be received by the user interface board 44 .
[0103] Also attached to the main circuit board is the USB chip 46 . USB chip mounts to the main circuit board 43 at a pin connection, and provides a pin connection for speaker 65 . The USB chip 46 is preferably mounted to the bottom surface of the main circuit board.
[0104] Also connected to the main circuit board is the scanner assembly 15 ( FIG. 42 ). The scanner assembly 15 generally includes a photodiode engine 53 , a photodiode board 54 , and a heat pipe 55 . In one embodiment, the photodiode engine 53 is directly mounted to the top surface of the photodiode board 54 , by one or more screws 56 , 57 , and 58 . In another embodiment, the bottom surface of the photodiode board is mounted to a foam fresen 59 . In the same embodiment, the foam fresen 59 is mounted to the bottom plate of the bottom section. In a preferred embodiment the foam fresen 59 has an orifice 69 which is adapted to receive the portion of the photodiode engine which houses the display light 62 . In a preferred embodiment the foam fresen 59 has a first arcuate cutout 75 at its front end and a second arcuate cutout 76 at its rear end. Arcuate cutouts 75 and 76 provide an arcuate surface for grommets 73 and 74 to be received.
[0105] The photodiode engine comprises a display light 62 ( FIG. 44 ). FIGS. 53, 61, and 65 are schematics of circuit diagrams relating to the photodiode engine and its peripheral connections. The display light 62 may be comprised of at least a red laser 63 and an infrared (IR) laser 64 . In a preferred embodiment red laser 63 may be a laser diode emitting light at a wavelength of 642 nm, and an infrared (IR) laser 64 that may emit light at a wavelength in the near infrared to be at 785 nm. Other combinations of wavelengths of more than two lasers may be used to enhance both the collection of the vein pattern and the display of the collected information. Red laser 63 projects an image of the vein pattern on the patient's skin. The laser diode has a wavelength of 642 nm, which is in the visible red region, but falls outside the spectral response range of photodiodes 60 and 61 . Red laser 63 illuminates areas with no veins, and does not illuminates areas with veins. This results in a negative image that shows the physical vein locations. Alternatively, the positive image may be used, where the red laser illuminates the vein locations and does not illuminate spaces between veins.
[0106] The red laser may be employed to project information other then vein locations, by means of turning on the laser or increasing its brightness when the laser beam is passing over the brighter parts of graphical or symbolic information to be projected, and turning off the laser or increasing its brightness when the laser beam is passing over the darker parts of graphical or symbolic information to be projected. Such information may include the vein depth, vein diameter, or the degree of certainty with which the device is able to identify the vein location, expressed, for example, through the projected line width 501 ( FIG. 66( a ) ), the length of the strokes in a dotted line 502 ( FIG. 66( b ) ), as a bar graph 503 ( FIG. 66( c ) ) or a numeric indication 504 ( FIG. 66( d ) ). It may also include user's cues 505 and 506 , respectively for optimizing the position of the device, such as choosing the correct tilt and distance to the target ( FIG. 66( e ) ).
[0107] Vein location and other information may also be displayed by projection means other than scanning laser, through the use of, for example, a DLP (Digital Light Processing) projector, a LCoS (Liquid Crystal on Silicon) micro-projector, or a holographic projector.
[0108] Additionally, the firmware of the photodiode board 54 may be programmed to recognize and modify display 14 , and projection by the display light 62 to represent a needle, catheter, or similar medical device 573 which has been inserted beneath a patient's skin and a part of it 573 a is no longer visible to the naked eye ( FIG. 70 ). The needle or medical apparatus may be made with, or coated with a material that absorbs or reflects a specified amount of the light from the IR laser 64 . Glucose is one example of a biomedical material which could be used as a coating to absorb or reflects a specified amount of an IR laser. Photodiodes 60 and 61 will detect the difference in reflection and absorption, and the photodiode board 54 may modify display 14 to show the needle or medical device. The photodiode board 54 may also be programmed to modify projection by the display light 64 so that the needle or medical device which has been inserted into the patient's skin is displayed.
[0109] More detailed information on the use of the laser light to view the veins can be found in U.S. patent application Ser. No. 11/478,322 filed Jun. 29, 2006 entitled MicroVein Enhancer, and U.S. application Ser. No. 11/823,862 filed Jun. 28, 2007 entitled Three Dimensional Imagining of Veins, and U.S. application Ser. No. 11/807,359 filed May 25, 2007 entitled Laser Vein Contrast Enhancer, and U.S. application Ser. No. 12/215,713 filed Jun. 27, 2003 entitled Automatic Alignment of a Contrast Enhancement System the disclosures of which are incorporated herein by reference.
[0110] The photodiode board 54 comprises one or more silicon PIN photodiodes, which are used as optical detectors in a preferred embodiment, photodiode board 54 comprises at least two silicon PIN photodiodes 60 and 61 ( FIG. 42A ). The field of view (FOV) of the optical detectors is preferably arranged to cover the entire area reachable by light from IR laser 64 . FIGS. 8 and 10 are schematics of circuit diagrams which represent the photodiode board and its peripheral connections. In front of these photodiodes 60 and 61 are filters 120 and 121 ( FIG. 42A ) to serve as an optical filters that transmit infrared light, but absorb or reflect light in the visible spectrum. Mounted to photodiode 60 and 61 may be photodiode masks 66 and 67 . Photodiode masks 66 and 67 comprise a shaped orifice 68 which is adapted to be received by photodiode 60 and 61 respectively. In a preferred embodiment photodiode masks 66 and 67 are circular and are adapted to be received by the cylindrical protrusions 31 and 32 of the housing bottom section 18 . The photodiode board 54 is further comprised of an orifice 70 . The opening 70 may be rectangular and adapted to receive the portion of the photodiode engine which houses display light 62 . In a preferred embodiment the photodiode board 54 has a first arcuate cutout 71 at its front end, and a second arcuate cutout 72 at its rear end. Arcuate cutouts 71 and 72 provide an arcuate surface for grommets 73 to be received.
[0111] Other arrangements of optical detectors may be used too. In one possible arrangement, depicted on FIG. 67( a ) , the photodiode's field of view (FOV) 510 may be shaped by lenses-Fresnel lenses, curved mirrors or other optical elements 511 —in such way that the FOV extent on the patient's arm becomes small and generally comparable with the size of the IR laser spot 512 . This reduced FOV is forced to move synchronously with the laser spot by virtue of directing the optical path from the patient's arm to the photodiodes through the same scanning system 513 employed for the scanning of the laser beam, or through another scanning system, synchronous with the one employed for the scanning of the laser beam, so the FOV continuously overlaps the laser beam and follows its motion. Additional optical elements, such as a bounce mirror 514 , might be used to align the laser bean with FOV. Such an arrangement is advantageous in that it enables the photodiodes to continuously collect the reflected light from the IR laser spot while the ambient light reflected from the rest of the target generally does not reach the photodiodes.
[0112] Alternatively, the FOV of the photodiodes may be reduced in only one direction, and routed through the scanning system in such way that it follows the laser beam only in the direction where the FOV has been reduced, while in the other direction the FOV covers the entire extent of the laser scan ( FIG. 67( b ) ). Such FOV may be shaped, for example, by a cylindrical lens in front of a photodiode. As the laser spot 512 is moving along a wavy path defined by superposition of the fast horizontal scan and slow vertical scan, the FOV moves only vertically, which the same speed as the slow vertical scan, thus covering the scan line the laser spot is currently on. Such arrangement may be implemented, for example, by routing the FOV of the photodiode only through the slow stage of the scanning system 513 , but not its fast stage. Yet alternatively, the FOV may be shaped to follow the laser beam in close proximity without overlapping it ( FIG. 67( c ) ). In this case, the FOV still moves in sync with the laser spot 512 , but since it does not include the laser spot itself, the light reflected from the surface of the skin does not reach the photodiode. Instead, some portion of the light which penetrates the body, and, after scattering inside tissues, re-emerges from the skin surface some distance away from the laser spot, forming an afterglow area 515 , which is partly overlapped with FOV. Collecting only the scattered light while reducing overall signal strength, has the advantage of avoiding variations caused by non-uniform reflections from random skin features and may be helpful in discerning deep veins.
[0113] Multiple photodiodes may also be arranged in an array in such way that their individual FOVs cover the entire area illuminated by the IR laser. At any given moment, only the signals from one or more photodiodes whose FOV overlap the laser beam or fall in proximity to it may be taken into the account.
[0114] The photodiodes convert the contrasted infrared image returning from the patient into an electrical signal. The photodiode board 54 amplifies, sums, and filters the current it receives to minimize noise. The return signal of the photodiode engine 53 is differentiated to better facilitate discrimination of the contrast edges in the received signal received by photodiodes 60 and 61 . FIG. 71 ( a ) represents a typical signal collected from photodiodes 60 and 61 and digitized. Local peaks 580 correspond to the locations of veins in the patient body. FIG. 71 ( b ) represents the same signal after the differentiation. Since differentiation is known to remove the constant parts of the sip al and amplify its changing parts, peaks 580 a can be easily found by comparison to ground reference (zero signal level of FIG. 71( b ) ). The photodiode board 54 also determines the locations where the infrared light has the lowest signal reflectivity using a scan system. These lower reflectivity locations indicate the vein locations.
[0115] Signal processing methods other than differentiation, including Digital Signal Processing (DSP) may be employed as well, such as Fast Fourier Transform (FFT), Finite Impulse Response (FIR) and Infinite Impulse Response (IIR) filtration. Additionally, more complex image processing algorithms might be used, for example based on continuity analysis, as the veins generally form continuous patterns. For example, FIG. 72 shows a few consecutive scan lines crossing a single vein 592 . While most lines produce distinctive signal peaks 590 , indicating the vein location, in some lines those picks might by masked by noise 591 . Still, connecting the vein location points derived from distinctive picks allows the algorithm to establish and display the true location of the vein.
[0116] To facilitate the use of DSP algorithms, the electronic circuitry to digitize the signal from the photodiodes and store it subsequently in some form of digital memory might be provided. Consequently, the display of the vein pattern by the red laser might be delayed with respect to the acquisition of said pattern with the IR laser. Such delay may vary from a small fraction of the time interval needed to scan the entire display area to several such intervals. If necessary, an intentional misalignment between the red and IR laser might be introduced, so the red laser can light up or leave dark the areas where the IR laser detected the lower or higher reflectivity, although the red laser beam would travel through those areas at different times than the IR laser.
[0117] The scan system employed by the apparatus 10 of the present invention uses a two dimensional optical scanning system to scan both the infrared and visible laser diodes. A dichroic optical filter element 125 in FIG. 44 allows laser diodes 63 and 64 to be aligned on the same optical axis and be scanned simultaneously. This allows for a minimal time delay in detecting the infrared reflected signal, and then re-projecting the visible signal.
[0118] The scan system employed by the apparatus 10 of the present invention has a horizontal and vertical cycle. Vertical scanning is driven in a sinusoidal fashion, and in one embodiment it occurs at 56.6 Hz, which is derived from 29 KHz sinusoidal horizontal scan. The Scan system is also interlaced. During a horizontal cycle the projection system is active only one half the horizontal scan system and blanked during the alternate half of the scan cycle. On the alternate vertical cycle the blanked and active portion of the horizontal scan is reversed. The top and bottom areas of the scan are blanked as well with a small area at the top of scan, located behind a mechanical shield for safety, reserved for execution of a laser calibration activity.
[0119] Alternative scan system might be used as well, such as those using a single scanning mirror deflectable in two orthogonal directions, or two uni-directional mirrors with smaller ratios of horizontal and vertical frequencies, such that the scan pattern forms a Lissajou figure (See http://www.diracdelta.co.uk.science/source/l/i/lissajous%20figures/source.html, and for animated figures, http://ibiblio.org/e-notes/Lis/Lissa.htm, which are incorporated herein by reference).
[0120] Various mechanical arrangements for scanning mirrors may be used. In one embodiment ( FIG. 63 ) the mirror 550 , made of glass, plastic or silicon, is attached to a free end of a cantilevered torsion fiber 551 , made of glass or other linearly-deformable material, the other end of which is fixed to a base plate 552 . A magnet 553 , polarized in a direction perpendicular to the fiber, is attached to the fiber between the base plate and the mirror. A coil 554 may be positioned in close proximity to the magnet. The coil 554 may be used both for driving the mirror by virtue of energizing it with AC current, as well as for collecting the positional feedback by virtue of amplifying the voltage induced in the coil by magnet's oscillations. Both functions may be accomplished simultaneously, for example, by using one half of the mirror's oscillatory cycle for driving and the other half for collecting feedback. Alternatively, other means of driving the mirror, such as inducing torsional oscillation on the entire base plate by means of a piezo-electric element 555 , might be used. The magnet 553 and the coil 554 are used exclusively for feedback in this case.
[0121] The torsion mode of the fiber 551 may be higher than fundamental, meaning that at least one torsional node, i.e. a cross-section of the fiber which remains still during oscillations, is formed. Such nodes allows for generally higher oscillation frequency at the expense of generally lower oscillation amplitude.
[0122] Since high oscillation frequency is desirable to obtain high-resolution images at smooth video rates, the linear speed of the mirror's outer edges becomes quite high as well, leading to excessive dust buildup along those edges. To alleviate this problem, the edges of the mirror may be smoothed by either removing some mirror material 560 ( FIG. 69 ), or adding a layer of bevel-shaped coating 561 around the edges of the mirror.
[0123] Non-mechanical scanning systems, such as acousto-optic, electro-optic or holographic might be employed as well.
[0124] In a preferred embodiment, each scan line is divided into 1024 pixels numbered 0 - 1023 . In pixel range 0 - 106 , red laser 63 is at its threshold, and IR laser 64 is off. The term “threshold”, as applicable to lasers, means an inflection point on the laser Power-Current (P-I) curve, where the current becomes high enough for the stimulated emission (aka “lasing”) to begin. This point is marked Ith of FIG. 73 , which, while taken from the documentation of Sanyo Corp., is representative of the vast majority of laser diodes. In pixel range 107 - 146 , red laser 63 is active, and IR laser 64 is at its threshold. In pixel range 182 - 335 , red laser 63 is active, and IR laser 64 is on. In pixel range 886 - 915 , red laser 63 is active, and IR laser 64 is off. In pixel range 916 - 1022 , red laser 63 is at its threshold, and IR laser 64 is off. In pixel range 0 - 106 , red laser 63 is at its threshold, and IR laser 64 is off.
[0125] Projection is accomplished by loading the appropriate compare registers in the complex programmable logic device, or CPLD. The content of the registers is then compared to the running pixel counter, generating a trigger signal when the content of a register matches the pixel count. The “left” register is loaded with the pixel count of when the laser should be turned off and the “right” register loaded with the pixel count of when the laser should be turned back on. The registers should be loaded on the scan line prior to the line when the projection is to occur. Projection is only allowed during the “Active” part of the red laser scan, i.e. between pixels 107 and 916 , as explained above.
[0126] To improve vein visibility it is important to maintain the laser spot of a proper size on the surface of the patient's skin. This may be accomplished by fixed laser-focusing optics, or by an auto-focusing system which adjusts the beam focusing in response to changes in the distance to the target.
[0127] Certain patient's veins or a portion of their veins might not be displayed well or at all. Causes for veins not be displayed include vein depth skin conditions (e.g. eczema, tattoos), hair, highly contoured skin surface, and adipose (i.e. fatty) tissue. The apparatus is not intended to be used as the sole method for locating veins, but should be used either prior to palpation to help identify the location of a vein, or afterwards to confirm or refute the perceived location of a vein. When using the apparatus qualified medical personnel should always follow the appropriate protocols and practices.
[0128] In one embodiment, when the user wishes to operate the apparatus, the user may apply a perpendicular force to the top surface of the side button 113 , or depress power button 112 to power the device. Once the device has been powered, the user can turn on the display light 62 by pressing and holding the top surface of the side button 113 for a set amount of time. In a preferred embodiment the photodiode board 54 has been programmed to activate the display light 62 after the user has held side button 113 for a half second.
[0129] Embedded in the user interface board 44 may be firmware, which supports the displaying, upon LCD 14 , of a menu system (see FIGS. 15-22 ). The menu system permits a user to access a plurality of features that the apparatus of the present invention can perform. The user can cycle through different display modes that the firmware has been programmed to transmit to the display by tapping the top surface of the side button 98 . The features embedded in the firmware can include a menu system, menu settings, display status. In one embodiment, the first LCD button 110 is programmed to access the menu mode ( FIG. 15 ). One of those features of the firmware permits labeling or naming of a particular apparatus, as seen in FIG. 20 . Such labeling may become advantageous in an environment where a medical service provider utilizes a plurality of the apparatus 10 , such as in an emergency room. The plurality of apparatus 10 may be maintained in a corresponding plurality of rechargeable cradles 5 , which may be mounted to a bracket 200 , and secured thereto using fastening means 201 , as seen in FIG. 29 . Power to the cradles 5 may be supplied from an adapter 202 plugged into a wall outlet, with a power splitter 203 supplying power to each cradle 5 . Each of the plurality of apparatus 10 in this example may be appropriately labeled, “ER1,” “ER2,” . . .
[0130] When the apparatus's 10 display light 62 is activated, the apparatus 10 can be used to locate veins. The user can access the scan function by navigating to it using the keypad 13 . The firmware will contain a feature which will allow the user to cycle through display settings using a menu system to optimize vein display for the current subject. When the display light 62 is deactivated, the display 14 remains available for viewing status and making configuration settings using the menu system. | A portable vein viewer apparatus may be battery powered and hand-held to reveal patient vasculature information to aid in venipuncture processes. The apparatus comprises a first laser diode emitting infrared light, and a second laser diode emitting only visible wavelengths, wherein vasculature absorbs a portion of the infrared light causing reflection of a contrasted infrared image. A pair of silicon PIN photodiodes, responsive to the contrasted infrared image, causes transmission of a corresponding signal. The signal is processed through circuitry to amplify, sum, and filter the outputted signals, and with the use of an image processing algorithm, the contrasted image is projected onto the patient's skin surface using the second laser diode. Revealed information may comprise vein location, depth, diameter, and degree of certainty of vein locations. Projection of vein images may be a positive or a negative image. Venipuncture needles may be coated to provide visibility in projected images. | 0 |
This application is a continuation-in-part of application Ser. No. 703,268 filed Feb. 20, 1985 now abd.
BACKGROUND OF THE INVENTION
This invention relates to a double ranging drum cutter having a load controller, in which the height and running speed of a cutter drums in a double ranging drum cutter used for long wall type coal extraction are automatically controlled such as to prevent overload on the cutter drums.
Description of the Prior Art
In the long wall type coal extraction arrangement of the prior art with a double ranging drum cutter, the operator judges the state of the load on the cutter drum from the vibrations and noise of the drum cutter body and sparks of contact of the drum cutter body with bedrock produced when the cutter drum is cutting the bedrock in contact therewith, and controls the height of the cutter drum and running speed of the double ranging drum cutter in an atmosphere containing floating mine dust with the operator's five senses so that no excessive load is applied to the cutter drum. Therefore, the operation of the drum cutter requires considerable skill. Also, it is difficult to completely prevent the application of overload to the cutter drum.
OBJECTS OF THE INVENTION
A first object of the present invention is to provide a double ranging drum cutter, which comprises a drum cutter body, cutter drums provided on the opposite ends of the drum cutter body in the running direction thereof for controlling the height by drum height controllers, cutter head vibration measuring units mounted on the drum cutter body, a cutter motor load measuring unit mounted on the drum cutter body, and a controller mounted on the drum cutter body and with a control data setter connected to the controller, the cutter head vibration measuring units and cutter motor load measuring unit being connected to an input section of the controller, a running speed controller provided on the drum cutter body and drum height controllers being connected to an output section of the controller, and in which the load applied to the cutter drums is judged indirectly from the vibrations of the cutter head and motor load current during the cutting, and the height of the cutter drums and the running speed of the double ranging drum cutter are automatically controlled through feedback control, thus permitting ready operation of the double ranging drum cutter even by a person who is not skilled while reliably preventing overload applied to the cutter drums.
A second object of the present invention is to permit automatic operation of the double ranging drum cutter by the remote control while reliably preventing the application of overload to the cutter drums.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view showing an embodiment of the double ranging drum cutter having a load controller according to the inventive concept;
FIG. 2 is a simplified block diagram showing a control circuit;
FIG. 3 is a circuit diagram showing a controller gating circuit;
FIG. 4A and Fib. 4B are a block diagram load control flow chart, FIG. 4A being the top of the flow chart and FIG. 4B being the bottom of the load control flow chart;
FIG. 5 is an enlarged view of FIG. 2;
FIG. 6 is a plan view of FIG. 1; and,
FIG. 7 shows a fragmentary left side view of FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a double ranging drum cutter having a load controller according to the present invention. A face conveyor 7 is provided on a lower bedrock 18 such that it extends in the longitudinal direction toward the front of a coal layer 6. A drum cutter body 1, which comprises a cutter motor section 8, a running speed controller 5, a haulage 9, a rear or left cutter assembly head 11 having a left drum height controller 10 and a front or right cutter assembly 13 having a right drum height controller 12, is mounted on the face conveyor 7 such that it is movable in the longitudinal direction of the conveyor. A left cutter drum 14 is supported for vertical movement by the left drum height controller 10, and a right cutter drum 15 is supported for vertical movement by the right drum heighth controller 12.
A controller 4 with a control data setter 3 connected thereto and a motor load measuring unit 2 are provided on the cutter motor section 8. A left cutter assembly vibration measuring unit 16 is provided on the left cutter assembly 11. A right cutter assembly vibration measuring unit 17 is provided on the right cutter assembly 13. The cutter motor load measuring unit 2 may be one, which senses the current in the cutter motor through a current transformer. Strain gauge type acceleration converters which can detect the acceleration in three directions, e.g. X, Y and Z, are used as the cutter head vibration measuring units 16 and 17. The vibration is measured from the detection signals for the three directions X, Y and Z in combination. The drum height controllers 10 and 12 are provided with motor-driven lifters.
Referring to FIG. 1, the double ranging drum cutter runs in the direction of arrow under the guide of the face conveyor. The left cutter drum 14 cuts in the coal layer 6 in the lower bedrock 18, and the right cutter drum 15 cuts in the coal layer 6 in an upper bedrock 19.
FIG. 2 shows a load control circuit. The circuit includes the controller 4 with the control data setter 3 connected thereto. The left cutter assembly vibration measuring unit 16, right cutter assembly vibration measuring unit 17 and cutter motor load measuring unit 2 are connected to an input section of the controller 4. An output section of the controller 4 is connected to the running speed controller 5, left drum height controller 10 and right drum height controller 12. The controller circuit is formed by comparators 20 and 21, an AND gate 22, and the controller 4. A cutter motor load is supplied from a power source for a cutter motor 32 through a cutter motor load measuring unit 2 to a controller 4. Also vibration information is supplied from left and right cutter head vibration measuring units 16 and 17. The controller 4 compares these input values to data set by a control data setter 3. When the controller 4 determines that there is an overload, it provides a speed control signal for a running speed controller 5.
The controller 4 controls the running speed while supervising data from a running speed sensor 30.
The running speed controller 5, which receives the speed control signal from the controller 4, operates a solenoid valve 27 for controlling the oil hydraulic circuit. The oil hydraulic circuit thus operates a cylinder 24, so that the cutter speed is controlled by the cylinder 24.
Further, left and right drum height controllers 10 and 12 for controlling the drum height are connected to the controller 4. These controllers 10 and 12 are each provided with solenoid valve 26, 28 and cylinder 23, 25 for controlling the oil hydraulic circuit. Further, an arm angle sensor 29, 31 for detecting the drum height is connected to the controller 4, so that the drum height is controlled in the same manner as in the control of the running speed.
With the system shown it is possible to freely select one of three system i.e., (a) one for controlling the running speed, (b) one for controlling the drum height and (c) one for controlling both of the running speed and drum height.
FIGS. 4A and 4B show an example of load control flow chart of the system shown in FIG. 3. In FIGS. 4A and 4B, control data input may be set as follows.
Cutter motor load: 110% & 5 sec. (indicating that the load is 110% or above continuously for 5 seconds).
Vibration: 150% & 3 sec. (indicating that the vibration is 150% or above continuously for 3 seconds).
Running speed down 2 m/min. (indicating that the speed is reduced stepwise at an interval of 2 m/min. in the control).
Return back load: 90% (indicating that speed up is adjusted if the load lever is reduced to be lower than 90% as a result of the control, while ending the control if the lever is above 90%).
The unit shown as controller 4 in FIG. 3 is made from commercially available components and has the following components:
a start switch 4a
control data input 33
running speed input 34
cutter motor load input 35
control memory ON 36
load continued input timer 37
load over memory ON 38
vibration continued timer 39
vibration memory 40
load over memory 41
return back memory ON 42
load over memory OFF 43
vibration memory OFF 44
vibration memory ON 45
control memory ON 46
running speed memorized 47
running speed down 48
speed down signal OFF 49
control timer counted 50
control timer count up 51
speed down signal ON 52
control memory OFF 53
control timer 54
load 55
return back memory OFF 56
return back memory ON 57
speed up signal ON 58
memorized running speed 59
speed up signal OFF 60
return back memory OFF 61
The following signal flow controls take place according to the magnitudes of the load current and vibrations:
I. Load current Preset value, Vibration Preset value START →33 →34 →35 →36 →37 →43 →39 →44 →41 →42 →END
II. Load current Preset Value, Vibration Preset value START →33 →34 →35 →36 →37 →38 →39 →44 →41 →45 →END
III. Load current Preset value, Vibration Preset value START →33 →34 →35 →36 →37 →43 →39 →40 →41 →42 →END
IV. Load current Preset value, Vibration Preset value START →33 →34 →35 →36 →37 →38 →39 →40 →41 →45 →46 →47 →48 →52 →END
V. The other functions items 53 through 61 are similar to the foregoing.
Thus, as shown in FIGS. 4A and 4B, the load that is applied to the cutter drums 14 and 15 when the coal layer 6 is being cut by the double ranging drum cutter of this embodiment, is detected by the vibration measuring units 16 and 17 mounted on the cutter assemblies 11 and 13 and motor load measuring unit 2. The controller 4 compares the detected load value and data that is set in the control data setter 3 according to the mechanical elements of the drum cutter and status of coal and bedrock and feedback controls the left drum height controller 10, right drum height controller 12 and running speed controller 5, whereby the load on the cutter drums is automatically controlled such as to prevent overload.
With reference to FIG. 3, the controller 4 also includes comparators 20 and 21. The comparator 20 compares the detection signals 16A and 17A from the cutter head vibration measuring units 16 and 17 and data signal 3A from the control data setter 3. The comparator 21 compares the detection signal 2A from the cutter motor load measuring unit 2 and data signal 3B from the control data setter 3. When an overload is detected, a load control command is fed through an AND gate 22 or OR gate to the left drum height controller 10, right drum height controller 12 and running speed controller 5, whereby the load is automatically controlled to prevent overload.
As herein before described, control data setter 3 includes a signal level setting function and a time setting function. When the time which exceeds the signal level setting value of the control data setter 3 has passed the setting time, the detection signals 2A, 16A and 17A are judged to be the state of overload, so that the load may be automatically controlled.
When it is believed that an overload is being applied to the lower cutter drum 14, more specifically, when the cutter drum 14 is cutting a relatively great amount of bedrock 18 having a large cutting resistance, the cutter arm 62 is rotated upwards to reduce the cutting ratio of the bedrock, so that the cutting resistance may be alleviated.
Further, if it is believed that the overload is applied to the upper cutter drum 15, more specifically, when the cutter drum 15 is cutting a relatively great amount of bedrock 19 having large cutting resistance, the cutter arm 63 is rotated downwards to reduce the cutting ratio of the bedrock so that the cutting ratio may be alleviated.
The controller 4 controls the running speed and the drum height by the load control command from the AND gate 22 as shown in FIG. 2.
More specifically, the overload state is judged by two functions, i.e., signal level setting function and time setting function. In this case, data signals 3A and 3B from the control data setter 3 include two signals respectively. One set of them are data signals 3A-a and 3B-a for level setting; and, the other set are data signals, 3A-b and 3B-b are for time setting. The comparator 20 in the controller 4 includes a signal level comparator 20-a and a time comparator 20-b. The comparator 21 in the controller 4 includes a signal level comparator 21-a and a time level comparator 21-b. These components are shown in FIG. 5. Output signals 64 and 65 detected by the signal level comparators 20-a and 21-a are compared with data signals 3A-b and 3B-b by means of the next stage time comparators 20-b and 21-b. When the signals exceed the setting of the data signals 3A-b and 3B-b, the judgement or conclusion is that the system is in a state of overload, so that the load may be controlled automatically.
It is to be observed therefore that the present invention provides an improvement in a double ranging drum cutter for moving along a face conveyor towards a coal layer and contemplates an elongated body 1 for moving along the face conveyor. This elongates body has a front and rear and a motor section 8. Front and rear cutter drums 14, 15 with adjustable cutter assemblies 11, 13 are at the front and rear. Also, front and rear drum height controllers 10, 12 are provided as well as front and rear cutter assembly vibration measuring means 16, 17 mounted on the body and coupled to the cutter assemblies. A motor load measuring unit 2 is mounted on the body and coupled to the motor section 8, also a running speed controller means 5. Also mounted on the body is a load controller 4 including a data setter 3. The running speed controller means 5, the drum height controllers 10, 11 are all connected to the load controller 4. Further, said load controller 4 has input and output sides, the vibration measuring units 16, 17 as well as the motor load measuring unit 2 being connected to the input side. Thus, the load controller 4 including first and second comparators 20, 21 receiving said inputs, the first comparator 20 receiving the input from the vibration measuring units 16, 17, a data signal 3A from the control data setter 3, the second comparator 21 receiving a signal from the motor load measuring unit 2 and a data signal 3B from the control data setter 3. A gate 22 is also connected to the first and second comparators 20, 21. This gate provides a command output to the front and rear height controllers 10, 11 and the running speed controller means 5 when an overload is detected. | According to the applicant's invention a load detector is used, in which a load sensor and a vibration sensor are combined using an AND gate. A load signal from the load detector is used for the feedback control of the cutter drum height and double ranging drum cutter running speed, so that a person who is not skilled can operate the double ranging drum cutter while preventing overload acting on the cutter drum. | 4 |
BACKGROUND OF THE INVENTION
This invention is an improved paint tray support device that allows attachment of a tray to a ladder. The tray support device has improved features enhancing both operational characteristics including ease of ladder attachment, paint tray stability and further having geometry enabling the paint tray support device to be attached to a variety of different trays, of different manufacturers.
DESCRIPTION OF RELATED ART
A common problem encountered when painting on a ladder is the absence of a convenient support at the higher ladder elevations for paint, trays, rollers, brushes and the like within convenient reach of the workers. A number of prior art devices have addressed this problem by providing detachable trays for ladders.
In order to provide maximum utility and versatility the supporting structure for a ladder tray should be easily demountable, equally suited for mounting on the left or right hand side of a ladder, and possess means for adjusting the angle of the attached tray to compensate for changes in ladder angle. Further economic and utilitarian advantages are realized by providing a detachable tray supporting structure having simply constructed mounting and adjusting means capable of inexpensive fabrication and easy operation. The means by which a tray support structure is attached to a ladder should be adaptable to fit all types and sizes of ladders commonly in use, such as wood, aluminum or fiberglass, by means of simple adjustment.
Although numerous prior art ladder trays and ladder tray supporting structures have been developed to solve certain of the aforementioned problems, none have adequately resolved all of the problems. As will become apparent from the discussion which follows, however the present invention solves each of the previously mentioned problems in a simple, inexpensive and expedient manner.
SUMMARY OF THE INVENTION
In a preferred embodiment, the invention may be described as a tray support device adapted to be adjustably attached to a ladder for supporting a tray containing paint or other liquid. The device includes a clamping assembly for attachment to a ladder and a tray, and an L-shaped support having a support leg and a mounting leg perpendicular to the support leg, thereby forming the L-shape. The support leg provides support to the bottom of the paint container when the device is mounted to the ladder. The mounting leg is attached to the clamping assembly. This mounting arrangement of the invention can be readily adjusted by the user to ensure that an attached tray can be maintained in a position level with the ground regardless of changes in ladder angle.
The clamping assembly includes a first clamping member positioned adjacent to an outside surface of the mounting leg and two tray clamp members positioned adjacent to an inside surface of the mounting leg. The first clamping member cooperates with the outside surface of the mounting leg of the L-shaped support to capture the side rail of the ladder therebetween. The first clamping member has the ability to be clamped to the side rails of aluminum, wood, fiberglass, and other types of ladders without undue stress on or deformation of the rails. The two tray clamp members are positioned adjacent to an inside surface of the mounting leg of the L-shaped support and cooperate to capture the lip and a portion of the sidewall of the paint tray therebetween. This assembly allows the paint container to be adjustably positioned at any vertical location of the ladder and is adaptable to various types of trays. It also allows for positioning of the container on either side of the ladder to accommodate both right and left-handed painters. Additionally, the assembly provides a universal mounting arrangement to accommodate most common types of ladders.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the paint tray support device showing the attachment of the device to a tray and a ladder
FIG. 2 is a front view of the paint tray support device illustrated in FIG. 1 not connected to the tray.
FIG. 3 is a side view of the paint tray support device illustrated in FIG. 1 .
FIG. 4 is an exploded view of the paint tray support device illustrated in FIG. 1
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
While the present invention will be described fully hereinafter with reference to the accompanying drawings, in which a particular embodiment is shown, it is to be understood at the outset that persons skilled in the art may modify the invention herein described while still achieving the desired result of this invention. Accordingly, the description which follows is to be understood as abroad informative disclosure directed to persons skilled in the appropriate arts and not as limitations of the present invention.
A preferred embodiment of the tray support device 10 of the present invention is shown in FIG. 1 attached to a ladder 12 and a tray 14 . The tray support device 10 is adapted to removably mount the tray 14 to the ladder 12 . The tray support device 10 is also adapted to releasably attach to a variety of ladders including free standing, extension and the like constructed out of materials such as metal, wood and fiberglass, having either a solid or channel configuration.
The tray support device 10 releasably attaches to a side rail 16 of the ladder 12 . The tray 14 , which may contain paint or other liquid, releasably attaches to the tray support device 10 and is positioned so the tray 14 is parallel to the ground to prevent the contents from spilling.
The tray support 10 includes a first clamping member 18 , a L-shaped support 50 , a first tray clamp member 60 , a second tray clamp member 80 and a pair of fasteners 38 and 39 with adjustment knobs 41 and 43 . The first clamping member 18 , as best shown in FIG. 4, includes a front surface 20 , a rear surface 22 and a pair of apertures 24 and 26 . The front surface 20 opposes the rear surface 22 and is spaced apart from the rear surface 22 by a gap 28 . The front surface 20 has a smooth finish but may incorporate a textured finish to provide additional friction when attached to the side rail 16 of the ladder 12 . The front surface 20 further includes a flange, not shown, that extends perpendicularly and outwardly along one edge of the front surface 20 . The front surface 20 further includes a groove, not shown, that extends along the length of the face adjacent to the flange. The front surface 20 further includes an adjustable bolt 34 extending vertically from the front surface 20 centrally located on the edge opposite flange. The rear surface 22 includes a pair of ribs 36 and 37 to strengthen the first clamping member 18 . Apertures 24 and 26 are positioned at opposite ends of the edge containing flange. Apertures 24 and 26 allow for a pair of fasteners 38 and 39 to pass through in a position that is perpendicular to both the front surface 20 and the rear surface 22 . When the tray support device 10 is attached to the ladder 12 , the front surface 20 comes into contact with an inside surface 17 of the side rail 16 , shown in FIG. 1, to prevent the tray support device 10 from moving when the tray 14 is attached to the ladder 12 for use. Unlike a wooden ladder, an aluminum or fiberglass ladder side rail is a hollow, 3-sided channeled member with the channel facing the center of the ladder. When the first clamping member 18 is engaged to the ladder side rail 16 the groove, not shown, comes in contact with the edge of the side rail 16 channel and the adjustable bolt 34 comes in contact with the bottom of the side rail 16 channel. When properly attached, the first clamping member 18 , with the aid of the adjustable bolt 34 if necessary, prevents the tray support device 10 from moving when the tray 14 is attached and in use. When the tray support device 10 is attached to a solid ladder, such as one constructed out of wood which does not have a channel configuration, the adjustable bolt 34 can be removed from the front surface 20 of the first clamping member 18 thereby allowing the front surface 20 to come into direct contact with the inside surface 17 of the ladder side rail 16 .
The L-shaped support 50 , as shown in FIG. 3, includes a support leg 52 and a mounting leg 40 perpendicularly connected to the support leg 52 thereby forming an L-shape. The support leg 52 includes a top surface 55 and a bottom surface 56 . The support leg 52 has an attached end 51 and a free end 53 wherein the attached end is connected to the mounting leg 40 and extends outwardly. As the support leg 52 extends outwardly, the width gradually tappers so the free end 53 is narrower than the attached end 51 . A recess 57 is defined between the inner surface 42 of the mounting leg 40 and the support leg 52 . A support leg rib 59 is attached to the bottom surface 56 of ate support leg 52 and is connected to the inner surface 42 of the mounting leg 52 and passes perpendicularly through the center of the recess 57 . The recess 57 is to extend the range of travel of the first tray clamp member 60 so a tray 14 with a shorter sidewall can be attached properly to the tray support device 10 . The mounting leg 40 , as shown in FIG. 4, includes an inner surface 42 and an outer surface 44 . The inner surface 42 is adapted to allow the first surface 62 of the first tray clamp member 60 to slide vertically along the inner surface 42 so the first tray clamp member 60 can be positioned to accept the lip 15 of the tray 14 . The mounting leg 40 , as shown in FIG. 2, includes three elongated slots 46 , 47 and 48 that allow fasteners 38 and 39 to pass therethrough, The elongated slots 46 - 48 allow adjustment of the tray support device 10 so the tray 14 can be properly fitted to the device 10 and leveled with the ground. The outer surface 44 , as shown in FIG. 4, includes a plurality of vertical ribs 49 which add strength to the mounting leg 40 . The outer surface 44 comes in contact with an outside surface 19 of the side rail 16 when the tray support device 10 is clamped to the ladder 12 , as shown in FIG. 1 .
Also forming part of the tray support device is a z-shaped bracket 60 designated as a first tray clamp member. The tray clamp member 60 defines a pair of apertures 63 and 64 through which fasteners 38 and 39 may extend. As best shown in FIG. 4 . Another aperture 65 is provided in an upwardly extending flange 66 also adapted to receive fasteners 38 or 39 therethrough. The first tray clamp member 60 defines a first surface 62 adapted to slide vertically along the inner surface 42 of the mounting leg 40 . The first tray clamp member 60 further includes a vertically extending notch 67 , best shown in FIG. 2, or groove in the lower end of the first tray clamp member 60 adapted to fit over the support leg rib 59 that passes through the recess 57 of the support leg 52 so as to prevent relative rotation between the first tray clamp member 60 and the support leg 52 .
The first tray clamp member 60 also includes an L-shaped shelf 68 , as shown if FIG. 4 defined by an outwardly extending leg 69 and an upwardly extending leg 70 . The upwardly extending leg 70 , the outwardly extending leg 69 and the flange 66 together form a channel 7 l, shown in FIG. 3, that accepts the paint tray lip 15 to allow attachment of the tray support device 10 to the tray 14 .
Also forming part of the tray support device 10 is a L-shaped bracket 80 designated as a second tray clamping member, as shown in FIG. 4 . The second tray clamping member 80 defines an aperture 82 through which either fastener 38 or 39 extends therethrough. The second tray clamping member 80 further includes an outer surface 84 and an inner surface 86 wherein the inner surface contains a flange 88 that contacts the inside surface of the edge of the tray 14 at the same position on the tray 14 as the first tray clamp member 60 , as shown in FIG. 3 . The outwardly extending flange 88 extends downwardly from the body of the second tray clamping member 80 and creates an L-shape. When fasteners 38 and 39 are tightened, the first tray clamping member 60 and the second tray clamping member 80 clasp the edge of the tray 14 to prevent movement.
When the fasteners 38 and 39 are tightened, the first clamping member 18 , the mounting leg 40 , the first tray clamp member 60 and the second tray clamp member 80 are drawn together to solidify the tray support device 10 to prevent movement when mounted to the ladder 12 and the tray 14 . To mount the tray 14 to the tray support device 10 , fasteners 38 and 39 are loosened so the second tray clamp member 80 can be separated from the first tray clamp member 60 , as best displayed in the exploded view in FIG. 4, and the first tray clamp member 60 can be vertically slid along the inner surface 42 of the mounting leg 40 . The lip 15 of the paint tray 14 is positioned between the first tray clamp member 60 and the second tray clamp member 80 where the lip rests in the channel 71 of the first tray clamp member 60 and the second tray clamp member 80 inner surface 86 comes in contact with the inner portion of the edge of the tray 14 . The tray 14 , first tray clamp member 60 and second tray clamp member 80 are advanced downward until the bottom of the tray comes in contact with the top surface 55 of the support leg 52 . When the bottom of the tray 14 reaches this position, the fasteners 38 and 39 are tightened so the first tray clamp member 60 and the second tray clamp member 80 clench the lip and inner surface of the paint tray 14 .
To attach the tray support device 10 to the side rail 17 of the ladder 12 , fasteners 38 and 39 are loosened so that the first tray clamping member 18 can be separated from the outer surface 44 of the mounting leg 40 . Since the apertures 24 and 26 have a diameter larger than fasteners 38 and 39 , an operator can easily separate the first champing member 18 by simply grabbing and sliding the member 18 in the direction away from the mounting leg 40 . The tray support device 10 is then positioned so the front surface 20 of the first clamping member 18 and the outer surface 44 of the mounting leg 40 are in contact with the inside surface 17 and the outside surface 19 of the ladder side rail 16 . The tray support device 10 is pivoted slightly until the tray 14 is parallel to the ground. When the tray 14 is in the proper position, fasteners 38 and 39 are tightened to compress the inside surface 17 and outside surface 19 of the ladder side rail 16 .
In certain situations, it may be desirable to position the tray holding device 10 on either the right or left hand side of the ladder depending on the amount of space available where the ladder 12 is placed or whether the operator is right or left handed.
Various features of the invention have been particularly shown and described in connection with the illustrated embodiment of the invention, however, it must be understood that these particular arrangements merely illustrate, and that the invention is to be given its fullest interpretation within the terms of the appended claims. | An improved apparatus for adjustably attaching a tray to a ladder side member. The apparatus includes a first clamping member for attachment to a ladder, an L-shaped support having a support leg and a mounting leg perpendicular to the support leg, thereby forming the L-shape and first and second tray clamping members, which allow a tray to be securely fastened to a ladder The support leg provides support to the bottom of the paint container when the device is mounted to the ladder. The mounting leg is attached to the clamping assembly and is provided with elongated slots therein for bolts to pass therethrough. The bolts also pass through the clamping assembly. The bolts are provided with threaded knobs and are used to draw the first clamp, the first and second tray clamp members and the mounting leg of the L-shaped support together when tightened. An additional slot is provided so that the position of the clamping assembly can be adjusted with respect to the mounting leg to accommodate attachment to a front or back side support of the ladder. | 4 |
BACKGROUND OF THE INVENTION
This invention pertains to instruments in the mechanical and technical drafting field used for drawing straight lines and specifically to an electronic drafting instrument which measures and displays its own linear displacement.
Despite the sophistication of modern engineering graphics, the measuring tools and techniques used by most draftsmen are essentially the same today as they were a century ago.
Most drafting measurements are made with scales, and dividers. When a scale is used to layout a measurement, an index mark on the scale is placed opposite a reference mark on the drawing another mark is placed opposite the desired measurement on the scale. An assortment of scales is usually required to accommodate different measuring units and scale factors.
When greater accuracy is required, measurements are usually taken between the open points of a pair of dividers and transferred to the drawing media by lightly pinpricking their location.
Using scales for layout measurements on complex drawings is time consuming, tedious and often eyestraining even for those with special skills.
It is, therefore, an object of this invention to provide a drafting instrument that will increase drawing efficiency, and reduce tedium and eyestrain.
The concept used to achieve that objective is embodied in an integral straightedged electronic drafting instrument which measures its own displacement and digitally displays the numbers in a large fixed size which is easy to read without eyestrain or the need for optical magnifiers.
The concept of a straightedge with some form of direct readout is old, but the physical embodiment of that concept taught in prior art such as U.S. Pat. Nos. 287,200 of Wach; 1,051,712 of Eager; 2,064,142 of Barany and 3,726,017 of DeMathe all have limitations for the professional draftsman.
Two of these limitations are: 1. lack of convenient easily read mean for displaying the total displacement beyond one revolution of a mechanical dial, 2. lack of convenient efficient means for automatically resetting the readout to zero.
In contrast to mechanical prior art self-measuring drafting instruments, this invention utilizes an electronic displacement sensor, an electronic up-down counter combined with a calculator type circuit, and an electronic digital display to overcome all of the above deficienceis.
The electronic principles involved are well known and are used, for example, in digital readout systems for lathes and milling machines, electronic digital planimeters, and electronic linear measuring probes.
Electronic linear measuring probes, which are electronic versions of mechanical cartometers, are of special interest because they could indeed by used to measure distances on drawings, as well as on maps. However, these probes are too cumbersome for creating original drawings because the readout, connected via a cable to the pen-like probe, is remote from the measuring probe. This is a serious limitation because the user is required to look away from the drawing surface to read the measurement corresponding to each probe position. Still another limitation is that such probes must be used in conjunction with a separate straightedge, and to draw a line the full length of the straightedge, the probe must be removed to make way for a pen or pencil.
It is, therefore, another object of this invention to provide an integral straightedged electronic drafting instrument which electronically measures its own displacement and gives a continuous readout of the linear displacement directly on the straightedge so the user does not have to look away from the drawing surface to read the digital display.
Yet another object of this invention is to provide an integral straightedged electronic drafting instrument which measures and displays its own displacement and can be used as a direct replacement for conventional scales and straightedges used on state-of-the-art drafting machines.
Another limitation of the prior art is that no means is provided to warn the user if the instrument is unknowingly lifted from the drawing surface during a measurement. This is important because the displayed results would be less than the true displacement. It is, therefore, another object of this invention to provide an integral straightedged drafting instrument which measures and displays its own displacement and has a contact sensor and annunciator to warn the user whenever the instrument is lifted such that the measurement may be in error.
SUMMARY OF THE INVENTION
This invention is a straightedged drafting instrument which measures its own displacement as it is moved over a drawing media and reads out the results on a large easy-to-read digital display. The display is mounted directly to the instrument near its leading straightedge so the user does not have to look away from the drawing to read the display.
The body of the instrument is a flat plate-like chassis or compartment which houses one or more drive wheels, a direction sensing displacement sensor such as an optical or electromagnetic direction sensing rotary incremental encoder, a pulse processing circuit comprised of an up-down counter and a calculator type circuit, a scale factor keyboard, a digital display such as the liquid crystal, light emitting diode, or electrofluorescent type, and a contact sensor and annunciator.
The direction sensing displacement sensor is driven by one or more wheels or rollers which are mounted to the plate and which turn when the plate is moved over the drawing media. The wheels are mounted to the plate such that the plate is lifted slightly above the drawing surface and may be moved about without smearing the drawing. The direction sensing displacement sensor produces electronic pulses as the plate is moved and the number of pulses is proportional to the displacement of the plate. The number of pulses from the sensor is processed by the combination up-down counter and calculator-type circuit, and readout on the digital display.
The display may be reset to zero at any time via the keyboard. The keyboard also allows the user to select any scale factor or length unit desired. The total length which can be measured is limited only by the number of digits which can be readout on the selected display. The smallest distance which can be measured is determined by the resolution of the rotary incremental encoder and 0.010 to 0.005 inch would be typical.
The calculator part of the pulse processing circuit may be used independent of its pulse processing function. The user could, for example, add or subtract any number to a displayed measurement, take the square root of a displayed measurement, or use the calculator for a computation unrelated to any measurement.
The contact sensor and annunciator are provided to warn the user that the drive wheel was lifted from the drawing surface and the displayed measurement may be in error and should be repeated. The annunciator is a sounder and/or blinking digital display.
The user of this invention is not required to learn complex new skills because it is used in the same manner as any straightedge.
In a typical use, for example, the leading straightedge is used to draw a straight line or it is aligned with an existing line or point on a drawing. When the instrument is moved to another position on the drawing, the displacement is continuously read out on the digital display. The instrument might be moved until some desired number is displayed, or used to measure the displacement between existing lines or points on a drawing. The leading straightedge of the instrument is always at the end point of any measurement.
In one preferred embodiment of this invention, the plate or chassis is sectioned into two parts or compartments and hinged together end-to-end such that one part may be attached to a commercial drafting machine while the other part remains free so its leading edge can be pressed into contact with a drawing surface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the drafting instrument showning a compartment with attached extension straightedge tilted downward.
FIG. 2 is a perspective view of the drafting instrument attached to a commercial drafting machine.
FIG. 3 is a perspective view of two instruments combined at right angles to each other and attached to a commercial drafting machine.
FIG. 4 shows an underside perspective view of the instrument attached to one tang of the protractor plate on a commercial drafting machine. A conventional scale is shown attached to the other protractor plate tang.
FIG. 5 is a partially exploded top perspective view of the instrument.
FIG. 5A is a back elevation view of the instrument partly sectioned along lines 5A--5A of FIG. 5 showing drive wheel, hinge pin, and contact sensor. The two compartments are shown unattached.
FIG. 5B is a cross-sectional view of the instrument taken on the line 5B--5B of FIG. 5 showing cone head bolt, plunger, etc.
FIG. 5C is a cross-sectional view of the instrument taken on the line 5C--5C of FIG. 5 showing fixed compartment attached to one tang of protractor plate of a commercial drafting machine.
FIG. 6 is a perspective view of an alternative embodiment of the instrument.
FIG. 7 is a top plan view of the instrument shown in FIG. 6 with cover removed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is illustrated a self-measuring electronic drafting instrument with a flat main chassis 10 having a straightedge portion 42 and a similar companion chassis or compartment 11 which are pivotally connected together end-to-end with hinge bolt 14 (shown in FIGS. 5 and 5A). The pivotal connection allows the plane of the main chassis to be changed while keeping that of the companion chassis fixed. The object of this feature in a preferred embodiment will be explained as this description proceeds. A rotatable drive wheel 12 is fixed to shaft 35 which rotates in bearings 21 and 22 (FIGS. 5 and 5A), that are attached to the main chassis. Drive wheel 12 protrudes below the underside of the main chassis 10 through opening 44. Shaft 35 need not show outside chassis 10, but is so drawn for clarity.
FIG. 2 shows the instrument attached to one tang 41 (see FIG. 4) of a standard protractor plate 39 on a commercial drafting machine 38 in replacement of a conventional straightedge scale such as 46.
The drive wheel 12 rotates when a force in the plane of the drawing media or similar surface is applied to the drafting machine or directly to the instrument. The drive wheel 12 is splined parallel to the shaft to provide positive rolling traction. If the direction of motion is parallel to the drive wheel shaft 35, such as indicated by arrow B, the wheel will not rotate, but will slide over the surface. If the direction of motion is diagonal, the instrument measures the component of displacement perpendicular to the shaft. Both ends of the drive wheel are rounded to prevent snagging the drawing media when the wheel must slide.
Rotation of the drive wheel 12 is transmitted by a pulley 34 (see FIG. 5) and belt 36, or other rotation transmission means such as a gear train, to an electronic direction sensing (clockwise or counterclockwise) rotary incremental encoder 13 such as U.S. Pat. No. 3,912,926 of Coulbourn which is fixed to chassis 10, and which produces pulses whose number are proportional to the rotational displacement of the drive wheel. The rotary encoder has a shaft (not shown) to which a pulley similar to 34 is fixed for accepting belt 36. The number of revolutions of the drive wheel, from some reference point, is directly proportional to the verticle component of the instrument displacement so the number of pulses produced by the incremental encoder is proportional to the vertical displacement. The encoder simultaneously produces two train of pulses which are 90° out of phase to each other so clockwise and counterclockwise rotation may be distinguished.
Pulses from the encoder are fed to an LSI semiconductor chip in package 19 which includes an up-down counter and calculator circuit, such as described in U.S. Pat. No. 3,924,110 by Cochran and Grant, and the number of processed pulses are read out on an electronic digital display with large easily read characters. The digital display is mounted in chassis 10 near the leading edge of the chassis so the user does not have to look away from his drawing to read the display. The display is electronically reset to zero by pressing a key on recessed scale factor keyboard 15 so the user may begin a new measurement at any reference point on the drawing. The up-down counter portion of the circuit in 19 adds to the displayed number when the instrument is moved upward (direction of arrow A) from some reference point and subtracts from the displayed number when the instrument is moved downward (opposite direction of arrow A). All displacements above a zero reference point are displayed with a positive sign prefix while displacements below the reference point are displayed with a negative sign prefix. The display always shows the displacement from some point at which the display was reset to zero.
The calculator part of the circuit is used to automatically multiply or divide the number of pulses produced by any number chosen via the scale factor keyboard. That is, the calculator circuit allows the user to use any scale factor and any measuring system desired.
The true displacement may be displayed in centimeters, meters, inches, feet, etc. by recalling the appropriate calibration factor from the calculator's permanent memory. The calibration factor will depend on the drive wheel diameter, ratio of the pully diameter of the drive wheel shaft to that of the encoder shaft, and the number of encoder pulses produced per encoder revolution. The calculator's non-permanent memory is used to store measurements for later use. The display 16, LSI circuit package 19, and scale factor keyboard 15 are mounted on a common circuit board which is attached to the main chassis 10.
The scale factor keyboard 15 is operated by inserting a slender object such as the end of a pen or pencil through holes such as 31 in chassis cover 20. The recessed keyboard makes it less likely to unintentionally change a scale factor.
The combination of a driven encoder with an electronic digital display as described in this embodiment is capable of very high precision, but the user may unfortunately obtain erroneous measurements if he unknowingly temporarily lifts the instrument during a measurement and the drive wheel temporarily stops rotating. The displayed measurement would be less than the true displacement. To avoid this potential source of error, the instrument is provided with a contact sensor or switch 17 (see FIGS. 5 and 5A) which is attached to chassis 10 and which activates sounder 18 whenever the instrument is lifted enough that the drive wheel might slip. The spring loaded actuating pin 47 of switch 17 has a rounded end 48 (FIG. 5A) which slides over the drawing media. The sounder 18 is silenced by temporarily depressing button 37 mounted on the side of chassis 10.
A power source such as rechargeable batteries 29, a voltage regulator 28, main power switch 23, and an AC adaptor-recharger jack 25 for plug 24 are housed in companion chassis 11 and its cover plate 26. The main chassis 10 and companion chassis 11 have through openings 49 and 50 (see FIGS. 5B and 5C) to pass internal power cable 51 from chassis 10 to chassis 11.
It was mentioned in the beginning of this description that chassis 10 and chassis 11 are pivotally connected together with hinge bolt 14 (see FIGS. 5 and 5A) so that the plane of main chassis 10 could be changed while keeping that of companion chassis 11 fixed. We are now in a better position to explain the purpose of that feature.
Drive wheel 12 holds chassis 10 and 11 slightly above drawing media to prevent unnecessary resistance to motion, prevent smearing finished drawings, and also to prevent the extension straightedge 27 from snagging edges of the drawing media. However, the straightedge should be in direct contact with the drawing media whenever it is alligned opposite a reference point or it is used to guide a pen or pencil for drawing a line. The pivotal connection between chassis 10 and 11 achieves that objective. The companion chassis 11 is rigidly attached to a part of the drafting machine protractor plate tang 41 (see FIG. 4) with bolt 53 and nut 54 (see FIG. 5C) but the leading edge of main chassis 10 may be tilted downward in direction indicated by arrow C in FIGS. 1 and 5B so extension straightedge 27 touches the drawing media. FIG. 5A shows that hinge bolt 14 screws into chassis 10 and rotates in bearings 56 and 57. The spring 59 keeps chassis 10 and 11 close together against thin thrust washer 60, but still allows free pivotal movement without requiring critical adjustment of hinge bolt 14. The leading edge of chassis 10 is prevented from dragging and is kept in essentially the same plane as chassis 11 by a restoring means consisting of cone head bolt 62 (see FIG. 5B) plunger 63, restoring spring 64, and adjusting screw 65. The chassis 10 has a cavity 66 for the plunger, restoring spring, and adjusting screw. The cavity is large enough for the plunger 63 to slide freely. When a force perpendicular to the plane of the drawing media (direction indicated by arrow C in FIGS. 1 and 5B) is applied near the leading edge of chassis 10, chassis 10 pivots about hinge bolt 14, and plunger 63 slides down the tapered side of cone head bolt 62 compressing restoring spring 64. When the applied force is removed, the compressed spring 64 forces the plunger 63 to slide back up the cone head bolt 62 and restores the chassis to its original plane. Note that the cone bolt 62 is rigidly attached to tang 41 by nut 68 and that hole 33 in chassis 10 is sufficiently large so the chassis does not touch the cone bolt 62. If it did, it would interfere with its free pivotal motion. Note also that there is sufficient clearance between the top surface of tang 41 and chassis 10 to allow the chassis to pivot enough for the straightedge to touch the drawing media.
The adjusting screw 65 is used to increase or decrease the compression of spring 64 and, thereby, vary the force required to press the extension straightedge into contact with the drawing media.
The opening 30 in cover 20 (see FIGS. 1 and 5) allows the user to place a finger on the drive wheel to control small movement of the instrument. The opening 30 also allows the wheel to be cleaned without turning the instrument over. The opening 32 in cover 20 is for display 16.
The invention is not limited to the particular details of construction of the embodiment depicted, and it is expected that modifications and applications will occur to those skilled in the art.
For example, it is clear that two independent instruments could be used on a commercial drafting machine to replace both conventional scales, or that an alternative embodiment could combine two instruments at right angles to each other as in FIG. 3. Rotation of wheel 12 is proportional to the vertical component of displacement and is read out on display 16. The rotation of wheel 120 (in FIG. 3) is proportional to the horizontal component of displacement and read out on display 160.
It should also be clear to those skilled in the art that the instrument may be used on drafting machines other than the depicted elbow type.
FIG. 6 shows still another embodiment for use without a drafting machine. It uses two displaced drive wheels, 12 and 72, on a common axis. Only one wheel, 12, drives the encoder. In this embodiment the pivotal connection between chassis 10 and 11 is unnecessary because the entire instrument can be pivoted about shaft 35 and 55 shown in FIG. 7. The leading edge is lifted above the drawing media by applying a downward force along the rear edge of the instrument, behind the axial line of the drive wheels, as indicated by arrow D in FIG. 6.
The leading edge is normally touching the drawing media and is lifted as described whenever the instrument is moved over a drawing. Note that this is opposite from the embodiment, used with drafting machines, where the leading edge of the instrument is normally held above the drawing media and a force must be applied, such as indicated by arrow C in FIG. 1, to make it touch the media.
The embodiment with two independent drive wheels (FIG. 7) would be used to follow an external straightedge. It is well known that if both wheels are fixed to a common shaft, the instrument will track in a straight line without external guidance.
An application which will be evident to those skilled in the art is that the instrument may also be used to measure angular displacement by using the equation A=D/R where A is the angular displacement in radians, D is the linear displacement along the arc, and R is the distance from the pivot point to the drive wheel. Commercial drafting machines have a built-in protractor which pivots about a point such as 40 shown in FIG. 4 so the distance R could be stored in the calculator memory such that angular displacements could be read directly. Similarly, the alternative embodiment shown in FIGS. 6 and 7 could be pivoted through an aperture 67 in the chassis. The aperture could be accurately positioned over the desired pivot point on a drawing by looking through the aperture.
Therefore, because certain changes may be made in the above described instrument without departing from the true spirit and scope of the invention, it is intended that the subject matter of the above depiction shall be interpreted as illustrative and not in a limiting sense. | Disclosed is an electronic integral drafting instrument which measures its own linear displacement and displays any desired multiple or submultiple of the actual displacement. The instrument includes a straightedged plate which houses: a displacement sensor with a driving wheel which projects beneath the plate, an electronic up-down counter and calculator type circuit, a scale factor keyboard, an electronic digital display, and a sensor which detects and annunciates if the displacement sensor driving wheel does not make proper contact with the drawing media. One embodiment of the invention is easily attached to conventional drafting machines as a replacement for regular straightedges and scales. A second embodiment of the invention may be used without a drafting machine. The leading straightedge of the instrument can be lifted or lowered into contact with the drawing media. An extension straightedge may be attached to the leading edge of the instrument. The instrument provides readout and storage of linear displacement in any unit system and any scale factor. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation application based on application Ser. No. 11/790,014, filed Apr. 23, 2007 now U.S. Pat. No. 7,403,040, the entire contents of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to reference voltage generators and methods for generating reference voltages. More particularly, one or more aspects of the invention relate to reference voltage generators, semiconductor systems employing such reference voltage generators and method for generating reference voltages that are configured to reduce and/or eliminate for termination mismatches.
2. Description of the Related Art
When transmitting signals between semiconductor devices, impedance matching may be performed to reduce signal reflection. Signal reflection, i.e., signal degradation, may occur if the impedance of a transmission line does not match that of a load being driven.
Signal reflections may cause distortion in the form of, e.g., ringing and/or stair-stepping, which may, in turn, lead to, e.g., false triggering in clock lines, erroneous bits in data, address and control lines, increased clock and signal jitter, etc.
Termination circuits such as termination resistors may be used to improve signal integrity, e.g., reduce signal reflection. Termination resistors may be provided internally and/or externally to a semiconductor device. Internally provided termination resistors may be referred to as on-chip termination resistors or on-die termination resistors.
Conventional termination circuits may include a receiver including a conventional reference voltage generator that provides a reference voltage based on a ground voltage and a power supply voltage of the receiver. In such devices, any variation in a ground voltage and/or a power supply voltage of a transmitter is not factored into the determination of the reference voltage. Thus, a data error rate of a logic level determination of data input signal may increase, and performance of the transmitter and receiver interface may be degraded. Termination circuits employing and/or generating more accurate reference voltage values are desired.
SUMMARY OF THE INVENTION
One or more aspects of the invention is therefore directed to reference voltage generators and methods for generating reference voltages, which may be employable by semiconductor systems and which substantially overcome one or more of the problems due to the limitations and disadvantages of the related art.
It is therefore a feature of an embodiment of the present invention to provide reference voltage generators capable of generating more accurate reference voltages based on at least one voltage signal from each of a transmitter unit and a receiver unit.
It is therefore a separate feature of embodiments of the present invention to provide a semiconductor device system employing a reference voltage generator capable of reducing and/or eliminating signal mismatch by providing more accurate reference voltages relative to conventional systems.
At least one of the above and other features and advantages of the present invention may be realized by providing a system including a plurality of transmission lines, a transmitter outputting respective signals to each of the plurality of transmission lines, a receiver receiving each of the plurality of signals via respective transmission lines, the receiver including a connection path connected to a termination voltage, a plurality of termination circuits distributed along the connection path, each termination circuit receiving a unique termination voltage from the connection path, receiving a respective signal and outputting a terminated input signal, a reference voltage generator including multiple reference voltage generator units connected to a common voltage, each reference voltage generator unit uniquely receiving at least one unique termination voltage and outputting a reference voltage, and a plurality of data input buffers receiving respective signals and an appropriate reference voltage of the multiple reference voltages output from the reference voltage generator.
The common voltage may be a first voltage signal based on a transmitter voltage. The system may include a first voltage transmission line, and the transmitter may include a first voltage driver outputting the first voltage signal to the first voltage transmission line. The first voltage signal may be supplied to each reference voltage generator through a common resistor. The multiple reference voltage generator units may be a plurality of reference voltage generator units and each reference voltage generator unit may receive a corresponding unique termination voltage.
Each reference voltage generator unit may include a first resistor between a reference node and the unique termination voltage, and a second resistor between the common voltage and the reference node. The second resistor may be common to all reference voltage generator units. The second resistor may be separate for each reference voltage generator unit. The common voltage may be a first voltage signal based on a transmitter voltage. The common voltage may include a first voltage signal and a second voltage signal. The first voltage signal may be based on a driver ground voltage of the transmitter and the second voltage signal is based on a driver power supply voltage of the transmitter.
The system may include a first voltage transmission line and a second voltage transmission line, and wherein the transmitter may include a first voltage driver outputting the first voltage signal to the first voltage transmission line and a second voltage driver outputting the second voltage signal to the second voltage transmission line. Each reference voltage generator unit may generate a reference voltage based on an average of a low signal and a high signal.
The low signal may be an average of the first voltage signal and a first termination voltage and the high signal is an average of the second voltage signal and a second termination voltage. The first and second termination voltages may be equal. The first and second termination voltages may be from adjacent termination circuits.
At least one of the above and other features and advantages of the present invention may be separately realized by providing a method of generating multiple reference voltages in a system having a plurality of transmission lines, a transmitter outputting respective signals to each of the plurality of transmission lines, and a receiver receiving each of the plurality of signals via respective transmission lines, the method including distributing a termination voltage along a connection path, generating a plurality of terminated input signals based on each of the plurality of signals and a corresponding unique termination voltage received from the connection path, and generating multiple reference voltages from unique termination voltages and a common voltage, and outputting a reference voltage for each of the plurality of terminated input signals.
Generating multiple reference voltages from the unique termination voltages and the common voltage may include using a plurality of resistors arranged between the each of the termination voltages received from the connection path and the common voltage. The method may include receiving the common voltage from the transmitter, wherein the common voltage may correspond to a voltage of the transmitter.
At least one of the above and other features and advantages of the present invention may be separately realized by providing a machine-readable medium that provides executable instructions, which, when executed by a processor, cause the processor to perform a method of generating multiple reference voltages in a system having a plurality of transmission lines, a transmitter outputting respective signals to each of the plurality of transmission lines, and a receiver receiving each of the plurality of signals via respective transmission lines, the method including distributing a termination voltage along a connection path, generating a plurality of terminated input signals based on each of the plurality of signals and a corresponding termination voltage received from the connection path, and generating multiple reference voltages from unique termination voltages and a common voltage, and outputting a reference voltage for each of the plurality of terminated input signals.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the attached drawings, in which:
FIG. 1 illustrates a first exemplary embodiment of a semiconductor device system employing one or more aspects of the invention;
FIG. 2 illustrates an exemplary data signal transmission path employable by the semiconductor device system shown in FIG. 1 ;
FIG. 3 illustrates an exemplary embodiment of a reference voltage transmission path employable by the semiconductor device system shown in FIG. 1 ;
FIG. 4 illustrates an exemplary embodiment of a receiver employing one or more aspects of the invention;
FIG. 5 illustrates a first exemplary embodiment of a reference voltage generator employable by the receiver shown in FIG. 4 ;
FIG. 6 illustrates a second exemplary embodiment of a reference voltage generator employable by the receiver shown in FIG. 4 ;
FIG. 7 illustrates a second exemplary embodiment of a semiconductor device system employing one or more aspects of the invention;
FIG. 8 illustrates a first exemplary embodiment of a receiver employable by the semiconductor device system shown in FIG. 7 ;
FIG. 9 illustrates an exemplary embodiment of a reference voltage generator employable by the receiver shown in FIG. 8 ;
FIG. 10 illustrates a second exemplary embodiment of a receiver employable by the semiconductor device system shown in FIG. 7 ; and
FIG. 11 illustrates an exemplary embodiment of a reference voltage generator employable by the receiver shown in FIG. 10 .
DETAILED DESCRIPTION OF THE INVENTION
Korean Patent Application No. 2006-0041798, filed on May 10, 2006, in the Korean Intellectual Property Office, is incorporated by reference herein in its entirety.
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. The invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout the specification.
In the following description, it will be understood that when elements are described as being connected to each other, they may be directly connected or one or they may be connected via one or more intervening elements. If elements are described as being directly connected, then the elements are directly connected to each other and there are no intervening elements therebetween.
FIG. 1 illustrates a first exemplary embodiment of a semiconductor device system 500 employing one or more aspects of the invention. The semiconductor device 500 may include a receiver 220 , a transmitter 320 , a first voltage signal generator 130 , and a plurality of transmission lines 30 a to 30 n connected between the transmitter 320 and the receiver 220 .
The first voltage signal generator 130 may include a first voltage transmission line 35 connected between the transmitter 320 and the receiver 220 . The first voltage transmission line 35 may be connected to a first voltage driver pin 75 of the transmitter 320 and a first voltage input pin 70 of the receiver 220 .
The transmitter 320 may include a plurality of data output drivers 50 a to 50 n , a plurality of data output pins 40 a to 40 n , and a first voltage driver 60 . The first voltage driver 60 may include a n-type transistor NT, e.g., an NMOS transistor, having a first terminal connected to the first voltage driver pin 75 and a second terminal connected to a driver ground voltage VSSQ. Each of the data output pins 40 a to 40 n of the transmitter 320 may be connected to a respective one of the data output drivers 50 a to 50 n . Each of the data output drivers 50 a to 50 n may be connected to a driver power supply voltage VDDQ and the driver ground voltage VSSQ. Each of the data output drivers 50 a to 50 n may supply a terminated data input signal IS 1 to ISn to a respective one of the data input pins 10 a to 10 n of the receiver 220 .
The receiver 220 may be supplied with a receiver power supply voltage VDD and may include a plurality of data input pins 10 a to 10 n . The receiver 220 may include a reference voltage generator 120 . The reference voltage generator 120 may include a plurality of input terminals connected to the receiver power supply voltage VDD via the power supply line 90 for receiving the termination voltage VDD. As a result of characteristics, e.g., resistance, of, e.g., the power supply line 90 , each of the input terminals may receive a respective termination voltage VDD 1 to VDDn based on the receiver power supply voltage VDD. That is, in embodiments of the invention, each of the termination voltages VDD 1 to VDDn may be different from one another.
Each of the data input pins 10 a to 10 n of the receiver 220 may be connected to the power supply line 90 via a respective one of a plurality of termination resistors RT. That is, e.g., each input terminal of the reference voltage generator 120 may be connected to the respective one of the data input pins 10 a to 10 n via the respective one of the plurality of the termination resistors RT connected therebetween. The reference voltage generator 120 may include a plurality of output terminals for outputting a respective one of the reference voltages VREF 1 to VREFn.
Referring to FIG. 1 , the reference voltage generator 120 may also be connected to the first voltage input pin 70 , and more particularly, to the first voltage signal generator 130 . Thus, in embodiments of the invention, the reference voltage generator 120 may receive a voltage signal corresponding to, e.g., the ground supply voltage VSSQ of the transmitter 320 , via the first voltage signal generator 130 . Accordingly, the voltage signal from the transmitter 320 may be employed by the reference voltage generator 120 to generate the respective reference voltages VREF 1 to VREFn. Thus, in embodiments of the invention, more accurate reference voltages may be generated.
The receiver 220 may include a plurality of data input buffers 20 a to 20 n . Each of the data input buffers 20 a to 20 n may receive the respective one of the reference voltages VREF 1 to VREFn from the reference voltage generator 120 . The data input buffers 20 a to 20 n may also receive the respective one of the terminated data input signals IS 1 to ISn, and may compare the respective one of the terminated data input signals IS 1 to ISn to the received respective one of the reference voltages VREF 1 to VREFn. Based on the comparison of the respective one of the terminated data input signals IS 1 to ISn to the respective one of the reference voltages VREF 1 to VREFn, the respective one of the data input buffers 20 a to 20 n may output a respective input signal CS 1 to CSn.
FIG. 2 illustrates an exemplary data signal transmission path of an open-drain type data driver employable by the semiconductor device system 500 shown in FIG. 1 . Referring to FIGS. 1 and 2 , each of the transmission lines 30 a to 30 n may have one end connected to a respective one of the data output pins 40 a to 40 n of the transmitter 320 and another end connected to a respective one of the data input pins 10 a to 10 n of the receiver 220 . The end of the respective transmission line 30 a to 30 n connected to the respective data input pin 10 a to 10 n may be connected to a first terminal of a respective termination resistor RT. Another terminal of the respective termination resistor may be connected to a termination voltage VTT, e.g., VDD 1 . In some embodiments of the invention, a low voltage VOL, a high voltage VOH and a corresponding reference voltage VREF of each of the terminated data input signals IS may be defined by the following three equations, respectively.
VOL=VTT×RON /( RON+RT ) (1) VOH=VTT (2) VREF =( VOL+VOH )/2 =VTT ×( RON+RT/ 2))/( RON+RT ) (3)
In Equation (1), VOL corresponds to a low voltage of the respective terminated data input signal IS, VTT corresponds to a termination voltage, RON corresponds to a resistance from the driver ground voltage VSSQ to the respective data input pin 10 a to 10 n of the receiver 220 , and RT corresponds to a resistance of the respective termination resistor. In Equation (2), VOH corresponds to a high voltage of the respective terminated data input signal IS.
FIG. 3 illustrates an exemplary embodiment of a reference voltage transmission path of an open-drain type voltage driver employable by the semiconductor device system 500 shown in FIG. 1 . Referring to FIGS. 1 and 3 , the first voltage transmission line 35 may have one end connected to the first voltage input pin 70 of the receiver 220 and another end connected to the first voltage driver pin 75 of the transmitter 320 , i.e., the first voltage driver 60 of the transmitter 320 . As shown in FIG. 3 , the reference voltage transmission path may include a pull-up resistor RU and a pull down resistor RD. The pull-up resistor RU may be connected between the respective termination voltage VTT and a reference node NR. The pull-down resistor RD may be connected between the reference node NR and a voltage node NL connected to the first voltage input pin 70 for receiving a respective voltage signal VL. In some embodiments of the invention, a reference voltage of the reference voltage transmission path may be defined by Equation (4).
VREF =( VOL+VOH )/ 2 =VTT ×( RON+RU )/( RON+RD+RU ) (4)
In equation (4), VOL and VOH respectively correspond to low voltage and a high voltage of the voltage signal VL, RON corresponds to a resistance from the driver ground voltage VSSQ to the voltage node NL, RU corresponds to a resistance of the pull-up resistor, RD corresponds to a resistance of the pull-down resistor, and VTT corresponds to a termination voltage supplied to a respective terminal of the pull-up resistor RU.
FIG. 4 illustrates additional features of the exemplary embodiment of the receiver 220 shown in FIG. 1 . As discussed above, the receiver 220 may include the reference voltage generator 120 . In some embodiments of the invention, the reference voltage generator 120 may include a plurality of reference voltage generating units 120 a to 120 n.
FIG. 5 illustrates a first exemplary embodiment of a reference voltage generator 121 employable as the reference voltage generator 120 of the receiver 220 shown in FIG. 4 . Referring to FIG. 5 , the reference voltage generator 121 may include a plurality of reference voltage generating units 121 a to 121 n . As shown in FIG. 5 , each of the reference voltage generating units 121 a to 121 n may include a pull-up resistor RU and a pull-down resistor RD. For each reference voltage generating unit 121 a to 121 n , the pull-up resistor RU may be connected to the pull-down resistor RD at a respective reference node NR 1 to NRn. As shown in FIG. 5 , the respective reference voltage VREF 1 to VREFn may correspond to a voltage at the respective reference node NR 1 to NRn.
More particularly, e.g., each pull-up resistor RU may be connected between the respective termination voltage VDD 1 to VDDn and the respective reference node NR 1 to NR 2 , and each pull-down resistor RD may be connected between the respective reference node NR 1 to NR 2 and the voltage node NL. As discussed above, a voltage of the voltage node NL may correspond to the voltage signal VL from the first voltage signal generator 130 . In embodiments of the invention, the pull-up resistors RU and/or the pull down resistors RD may be variable resistors having a resistance in accordance with a resistance control circuit (not shown).
More particularly, in the following description, resistors may be identified as variable and/or may be simply referred to as a resistor, however, any of the resistors may be a resistor having a predetermined value and/or a variable resistor. That is, embodiments of the invention, are not limited by the exemplary embodiments shown in the accompanying drawing figures.
As shown in FIG. 5 , the reference voltage generator 120 may receive the voltage signal, e.g., VL. Therefore, the reference voltage generator 120 may generate respective reference voltages VREF 1 to VREFn based on the voltage signal, e.g., VL, of the transmitter 320 as well as respective termination voltages VDD 1 to VDDn of the receiver 220 . Thus, embodiments of the invention may enable more accurate reference voltage(s) to be generated by the reference voltage generator 120 . Therefore, embodiments of the invention may also enable a data error rate of logic level determination of input data signals to be reduced and performance of the semiconductor device system 500 to be maintained and/or improved.
FIG. 6 illustrates a second exemplary embodiment of a reference voltage generator 122 employable as the reference voltage generator 120 of the receiver shown in FIG. 4 . In general, only differences between the first exemplary reference voltage generator 121 shown in FIG. 5 and the second exemplary reference voltage generator 122 shown in FIG. 6 will be described below.
As shown in FIG. 6 , in some embodiments of the invention, the reference voltage generator 122 may include a plurality of reference voltage generating units 122 a to 122 n . Each of the reference voltage generating units 122 a may include a pull-up resistor RU connected between a respective one of the termination voltages VDD 1 to VDDn and a respective one of the reference nodes NR 1 to NRn. In some embodiments of the invention, as shown in FIG. 6 , a common pull-down resistor RDC may be connected between all of the reference nodes NR 1 and the voltage node NL.
FIG. 7 illustrates a second exemplary embodiment of a semiconductor device system 600 employing one or more aspects of the invention. In general, only differences between the first exemplary semiconductor device system 500 shown in FIG. 1 and the second exemplary semiconductor device system 600 shown in FIG. 7 will be described below. In some embodiments of the invention, the semiconductor device system 600 may include a transmitter 340 , a receiver 240 , the plurality of transmission lines 30 a to 30 n , and a first and second voltage generator 150 .
Similar to the transmitter 320 of the first exemplary semiconductor device system 500 , the transmitter 340 of the second exemplary semiconductor device system 600 may include the plurality of data output drivers 50 a to 50 n and the plurality of data out put pins 40 a to 40 n . The transmitter 340 may also include a plurality of voltage driver pins 75 a , 75 b instead of the voltage driver pin 75 of the transmitter 320 . Each of the data output drivers 50 a to 50 n may be connected to the driver power supply voltage VDDQ and the driver ground voltage VSSQ.
Similar to the receiver 220 of the first exemplary semiconductor device system 500 , the receiver 240 of the second exemplary semiconductor device system 600 may include the plurality of data input pins 10 a to 10 n and a plurality of data input buffers 20 a to 20 n . The receiver 240 may also include a reference voltage generator 140 and a plurality of voltage input pins 70 a , 70 b , instead of the voltage generator 120 and the voltage input pin 70 , respectively, of the transmitter 220 .
The first and second voltage signal generator 150 may include a plurality of voltage transmission lines 35 a , 35 b . Each of the transmission lines 35 a , 35 b of the first and second voltage generator 150 may be connected between a respective one of the voltage driver pins 75 a , 75 b and a respective one of the voltage input pins 70 a , 70 b . More particularly, each voltage driver 60 a , 60 b of the transmitter 340 may be connected between a driver supply voltage, e.g., VDDQ, VSSQ, of the transmitter 340 and a respective one of the voltage driver pins 75 a , 75 b.
For example, in some embodiments of the invention, as shown in FIG. 7 , one of the voltage drivers, e.g., 60 b , may be connected between the driver power supply voltage VDDQ and the respective voltage driver pin 75 b , and another of the voltage drivers, e.g., 60 a , may be connected between the driver ground voltage VSSQ and the respective voltage driver pin 75 a . The voltage transmission line 35 a connected to the voltage driver 60 a , which may be connected to the driver ground voltage VSSQ, may provide a first voltage signal VL to the receiver 240 . The voltage transmission line 35 b connected to the voltage driver 60 b , which may be connected to the driver power supply voltage VDDQ, may provide a second voltage signal VH to the receiver 240 . The first voltage signal VL may correspond to a low voltage signal and the second voltage signal VH may correspond to a high voltage signal of the transmitter 340 .
Accordingly, as shown in FIG. 7 , the second exemplary reference voltage generator 140 may receive a plurality of voltage signals, e.g., VH and VL. Therefore, the reference voltage generator 140 may generate respective reference voltages VREF 1 to VREFn based on a plurality of voltage signals, e.g., VH and VL, of the transmitter 340 as well as respective termination voltages VDD 1 to VDDn of the receiver 240 . Thus, embodiments of the invention may enable more accurate reference voltage(s) to be generated by the reference voltage generator 240 . Therefore, embodiments of the invention may also enable a data error rate of logic level determination of input data signals to be reduced and performance of the semiconductor device system 600 to be maintained and/or improved.
FIG. 8 illustrates additional features of the exemplary receiver 240 employable by the semiconductor device system shown in FIG. 7 . More particularly, FIG. 8 illustrates additional features of the voltage generator 140 of the receiver 240 . As shown in FIG. 8 , the voltage generator 140 may include a plurality of reference voltage generating units 140 a to 140 n . Each of the reference voltage generating units 140 a to 140 n may receive each of the plurality of voltage signals, e.g., VH and VL, as well as the respective one of the termination voltages VDD 1 to VDDn. Thus, as discussed above, in some embodiments of the invention, the reference voltage generator 140 may generate respective reference voltages VREF 1 to VREFn using one or more of the voltage signals VH and VL corresponding to, e.g., drive supply and ground voltages VDDQ and VSSQ of the transmitter 340 .
FIG. 9 illustrates an exemplary embodiment of the reference voltage generator 140 employable by the receiver 240 shown in FIG. 8 . As shown in FIG. 9 , the reference voltage generator 140 may include n reference voltage generating units 140 a to 140 n . Each of the reference voltage generating units 140 a to 140 n may include a plurality of resistors, and more particularly, e.g., a pull-up variable resistor RU, a pull-down variable resistor RD, a first resistor R 1 and a second resistor R 2 . Resistances of the pull-up variable resistor RU and the pull-down variable resistor RD may be set by a resistance control circuit (not shown), which may be included in the receiver 240 . As discussed above, embodiments of the invention are not limited to the types of resistors, e.g., variable resistor or resistor having a predetermined resistance, shown in the accompanying Figures.
More particularly, as shown, e.g., in FIG. 9 , for each voltage generating unit 140 a to 140 n , the pull-down resistor RD may be connected between the respective termination voltage VDD 1 to VDDn and the first voltage signal VL, which may be supplied via a first voltage node NL of the reference voltage generator 140 , and the pull-up resistor RU may be connected between the respective termination voltage VDD 1 to VDDn and the second voltage signal VH, which may be supplied via a second voltage node NH of the reference voltage generator 140 . The first voltage node NL of the reference voltage generator 140 may be connected to a respective pull-down node ND of the voltage generating unit 140 a to 140 n , and the second voltage node NH of the voltage generator 140 may be connected to a respective pull-up node NU of the voltage generating unit 140 a to 140 n . The first resistor R 1 may be connected between the respective pull-up node NU and a respective reference node NR 1 to NRn of the voltage generating unit 140 a to 140 n , and the second resistor R 2 may be connected between the respective pull-down node ND and the respective reference node NR 1 to NRn of the respective voltage generating unit 140 a to 140 n . The respective reference node NR 1 to NRn may have a voltage corresponding to the respective reference voltage VREF 1 to VREFn generated by the reference voltage generator 150 .
FIG. 10 illustrates a second exemplary embodiment of a receiver 240 ′ employable by the semiconductor device system shown in FIG. 7 . In general, only differences between the first exemplary receiver 240 shown in FIG. 8 and the second exemplary receiver 240 ′ shown in FIG. 10 will be described below. As shown in FIG. 10 , the second exemplary receiver 240 ′ may include a reference voltage generator 160 instead of the reference voltage generator 140 . As shown in FIG. 10 , the reference voltage generator 160 may include a fewer number of reference voltage generating units 160 a to 160 c than a number of terminated data input signals IS 1 to ISn. That is, e.g., the reference voltage generator 160 , for receiving four terminated data input signals IS 1 to IS 4 , may include two, i.e., less than four, voltage generating units 160 a and 160 c . More particularly, in some embodiments of the invention, each voltage generating unit 160 a , 160 c may be shared by a plurality, e.g., two, of the terminated data input signals IS 1 to ISn.
Accordingly, as shown in FIG. 10 , each generated reference voltage, e.g., VREF 1 , VREF 3 , may be supplied to a plurality of the data input buffers, e.g., 20 a , 20 b , 20 c , 20 d.
FIG. 11 illustrates an exemplary embodiment of the reference voltage generator 160 employable by the receiver 240 ′ shown in FIG. 10 . In general, only differences between the exemplary reference voltage generator 160 shown in FIG. 11 and the exemplary reference voltage generator 140 shown in FIG. 9 will be described below. Each of the reference voltage generating units 160 a , 160 b may include a plurality of resistors, and more particularly, e.g., a pull-up variable resistor RU, a pull-down variable resistor RD, a first resistor R 1 and a second resistor R 2 . Resistances of the pull-up variable resistor RU and the pull-down variable resistor RD may be set by a resistance control circuit (not shown), which may be included in the receiver 240 ′.
More particularly, as shown, e.g., in FIG. 11 , one of the voltage generating units 160 a , 160 c may be associated with two of the termination voltages, e.g., VDD 1 , VDD 2 , VDD 3 , VDD 4 , and thus, in some embodiments of the invention, there may be half as many reference voltage generating units, e.g., 160 a , 160 c , as termination voltages, e.g., VDD 1 to VDD 4 and/or terminated data input signals, e.g., IS 1 to IS 4 . For each voltage generating unit 160 a , 160 c , the pull-up resistor RU, the first resistor R 1 , the second resistor R 2 and the pull-down resistor RD may be connected between one of the respective termination voltages, e.g., VDD 1 , and another of the respective termination voltages, e.g., VDD 2 . That is, e.g., the pull-up resistor RU, the first resistor R 1 , the second resistor R 2 and the pull-down resistor RD of the first reference voltage generating unit 160 a may be connected in series between the first termination voltage VDD 1 and the second termination voltage VDD 2 , and the pull-up resistor RU, the first resistor R 1 , the second resistor R 2 and the pull-down resistor Rd of the second reference voltage generating unit 160 c may be connected in series between the third termination voltage VDD 3 and the fourth termination voltage VDD 3 . For each of the voltage generating units 160 a , 160 c , e.g., a respective pull-up node NU may correspond to a node between the pull-up resistor RU and the first resistor R 1 , and the pull-up node NU may be connected to the second voltage node NH, and a respective pull-down node ND may correspond to a node between pull-down resistor RD and the second resistor R 2 , and the pull-down node ND may be connected to the first voltage node NL. A respective reference node NR 1 , NR 3 may correspond to a node between the respective first and second resistors R 1 , R 2 .
Exemplary embodiments of the present invention have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. While embodiments of the present invention have been described relative to a hardware implementation, the processing of present invention may be implemented in software, e.g., by an article of manufacture having a machine-accessible or readable medium including data that, when accessed by a machine, e.g., a processor, cause the machine to perform a method, according to one or more aspects of the invention, for generating a plurality of reference voltages. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims. | A system including a plurality of transmission lines, a transmitter outputting respective signals to each of the plurality of transmission lines, a receiver receiving each of the plurality of signals via respective transmission lines, the receiver including a connection path connected to a termination voltage, a plurality of termination circuits distributed along the connection path, each termination circuit receiving a unique termination voltage from the connection path, receiving a respective signal and outputting a terminated input signal, a reference voltage generator including multiple reference voltage generator units connected to a common voltage, each reference voltage generator unit uniquely receiving at least one unique termination voltage and outputting a reference voltage, and a plurality of data input buffers receiving respective signals and an appropriate reference voltage of the multiple reference voltages output from the reference voltage generator. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a steering arrangement, a restoring part and a steering system, particularly for commercial vehicles or utility vehicles.
[0002] Steering arrangements, particularly for use in commercial vehicles and trailers thereof, are well known in the prior art. Here, for example, an arrangement, on which the wheel of the commercial vehicle can be mounted and which is pivotable relative to the vehicle frame, is displaced by a tie rod transverse to the longitudinal axis of the vehicle such that the attached wheel carries out a pivoting movement. Furthermore, it is known in the prior art to provide a stabilizing unit, which damps vibrations of the steering arrangement and restores the steering arrangement to a neutral position, in which the commercial vehicle moves straightforward or in which the wheels rotate about an axis running perpendicular to the longitudinal axis of the vehicle. It is further known to supplement the force applied by the tie rod by an additionally arranged hydraulic or pneumatic actuating unit, wherein the actuating unit also ensures a so-called reverse lock or steering lock, i.e. the steering arrangement of the commercial vehicle is fixed in a certain pivot position. A disadvantage of the solutions known from the prior art is that a plurality of units have to be provided on the vehicle axle suspension system in order to ensure the plurality of functions. Negative consequences are a high weight, great space requirements and, due to the large overall contact surface for foreign matter swirled up in the chassis area, a high probability of damage and a reduced service life.
[0003] The object underlying the present invention is to provide a steering arrangement and a restoring part, which are as compact and light-weight as is possible and which at the same time fulfill the requirements on steering arrangements known from the prior art.
SUMMARY OF THE INVENTION
[0004] According to the invention, the steering arrangement, particularly for use in commercial vehicles and trailers thereof, comprises a tie rod unit or a tie bar unit, an actuating unit or a force unit and a lever element, the lever element being fixed in a pivotable or swivelable manner at a first turning point immovably disposed or arranged in a reference system, wherein the actuating unit has a restoring part, an active part and a damping part and is secured against displacement along a transverse axis relative to the reference system, at least one of the parts exerting a force on the tie rod unit to displace the tie rod unit along the transverse axis or to secure it against displacement along the transverse axis, wherein the tie rod unit is pivotably fixed at a second turning point on the lever element and therefore displacement of the tie rod unit along the transverse axis leads to a pivoting movement of the lever element about the first turning point. Preferably, the reference system, in relation to the vehicle, i.e. a motor vehicle or a commercial vehicle, is a fixed coordinate system with a transverse axis and a longitudinal axis running perpendicular thereto. The transverse axis runs particularly preferably perpendicular to the straightforward driving direction of the vehicle. Preferably, on the chassis of the vehicle a lever element is pivotably arranged, which preferably is the steering lever of a kingpin steering, which is known as such. Advantageously, the first turning point is located in a journal or bearing, which fixes the lever element on the vehicle frame pivotably and immovably or secured against translation, wherein the pivoting movement of the lever element particularly preferably takes place about a vertical direction essentially perpendicular to the plane spanned by the longitudinal direction of the transverse direction of the reference system. Preferably, the actuating unit is an assembly designed in the shape of a hollow cylinder, which is fixed at least against displacement along the transverse direction relative to the vehicle frame or relative to the reference system. According to the invention, the actuating unit comprises a restoring part, an active part and a damping part, wherein said three parts are in particular characterized by the function realized by them, and each comprise engagement means preferably engaging on the tie rod unit. The restoring part preferably has at least one restoring element, which preferably indirectly or directly transmits a force to the tie rod unit, in order to guide the latter into a position relative to the actuating unit or relative to the reference system, in which the lever element is arranged in a so-called neutral position or straightforward driving position. The straightforward driving position is in particular characterized in that bearing areas preferably provided on the lever element are positioned for rotatably mounting wheels on the lever element essentially along or parallel to the transverse axis. To put it differently, in the neutral position of the lever element, the steering deflection is zero. The restoring element arranged in the restoring part is preferably a spiral spring, which preferably may be subjected to pressure and which, when there is a steering deflection or a movement of the tie rod unit along the transverse axis to the left or to the right in relation to the commercial vehicle, exerts a force on the tie rod unit, which seeks to reset the latter to the neutral position. The active part of the actuating unit preferably serves for controlling the displacement of the tie rod unit relative to the actuating unit. Preferably, in the active part, there is a hydraulic or pneumatic coupling between the actuating unit and a piston provided preferably on the tie rod unit, wherein the actuating unit preferably in front of and behind the piston has supply and discharge channels for supplying and discharging a working fluid. By supplying or discharging a working fluid in the chambers of the actuating unit, which chambers are separated from each other by the piston, the piston is pushed to the left or to the right, in relation to the straightforward driving direction of the commercial vehicle. The functional principle of the active part preferably corresponds to a hydraulic or pneumatic piston system known from the prior art, in which a piston element is arranged in a hollow cylinder shaped component and separates the latter into two fluid sections, wherein by supplying or discharging the fluid in one of the two sections the piston element is displaced within the hollow cylinder shaped component. Alternatively to the hydraulic or pneumatic design of the active part, also a mechanical coupling by means of a tooth element, for example, which is in form-fit or positive engagement with a corresponding gear wheel or worm gear, may be ensured. The damping part of the actuating unit is adapted to cushion vibrations and shocks acting on the steering arrangement and/or the lever element by transmitting a damping force to the tie rod unit. Here, it is preferred that vibrations with a certain frequency, such as those caused by imbalances on the wheels, which cause periodic vibrations and in the case of a resonance may cause a self-oscillation of the entire steering system of the commercial vehicle, are limited to a safety-uncritical maximum. Preferably, the damping part is based on the principle known from the prior art of a hydraulic vibration damper, in which a fluid displaced by a piston element flows through valves or apertures or bores, whereby causing a flow resistance, which converts kinetic energy into thermal energy, and thus delays or damps a displacement of the components, which are movable relative to each other. Preferably, the actuating unit has an inner area and an outer, hollow body shaped area surrounding the inner area, wherein the active part and the damping part preferably are arranged in the inner area and the restoring part is preferably is arranged in the surrounding outer area. An advantage of integrating the active part, the damping part and the restoring part into the actuating unit is the particularly compact design as well as a reduction in weight, since preferably only one housing is required for the individual parts. Further preferably, the area provided on the lever element for mounting a wheel in the straightforward driving direction of the vehicle is arranged behind the first turning point. As is known, this arrangement is also referred to as trailing axle and in particular serves to achieve that the steering arrangement of the commercial vehicle by itself pivots back into the neutral position when the hydraulic system fails or when no controlling force acts on the steering system during the straightforward travel. The cause for this is the rolling resistance of the wheels of the vehicle acting behind the first turning point in relation to the straightforward driving direction, which resistance pivots the steering arrangement back into the neutral position. When the commercial vehicle travels backwards, it is in most cases necessary for the steering arrangement to be provided with a fixing or reverse lock function, which particularly preferably is realized by the active part of the actuating unit. To this end, if the active part is designed as a hydraulic or pneumatic component, the valves used for supplying and discharging the working fluid are closed, wherein the working fluid contained in the active part secures the tie rod unit against displacement along the transverse direction. Particularly preferably, the actuating unit is fixed on a rigid axle or on the rigid part of the steering axle of the vehicle, wherein the reference system in this case is disposed immovably to the rigid axle. Further preferably, at the distal ends of the rigid axle, preferably a respective first turning point is provided, on which a lever element is pivotably fixed.
[0005] Preferably, the tie rod unit passes through the actuating unit and is fixed at the respective distal ends thereof in a second turning point at respective lever element. Particularly preferably, the tie rod unit is guided in the actuating unit such that it may be displaced only along its main extension direction relative to the actuating unit. Furthermore, the tie rod unit preferably has various engagement sections, which engage the restoring part and/or the active part and/or the damping part and which transmit forces from each of said parts to the tie rod unit. Since the various functions of the steering unit are combined in the tie rod unit, it is possible to design the steering arrangement as compact as is possible and to save additional weight on the tie rod unit. Here, the tie rod unit carries out both the active steering, i.e. controlling the steering position of the steering arrangement, and the stabilization, i.e. preferably restoring the steering arrangement to the neutral position, and preferably the damping of vibrations occurring on the steering arrangement.
[0006] Preferably, the actuating unit is mounted pivotably relative to the reference system, so that displacement components of the second turning point perpendicular to the transverse direction are compensated by pivoting the actuating unit. The displacement components of the second turning point perpendicular to the transverse direction are transmitted via the tie rod unit to the actuating unit. Said displacement components of the second turning point perpendicular to the transverse direction are generated in particular in that the second turning point moves along a circular path. In order to prevent that the suspension of the actuating unit or of the tie rod unit bends or is damaged, it is preferred that the actuating unit is mounted pivotably relative to the reference system. The actuating unit can be mounted pivotably particularly preferably by a ball-and-socket joint or by an arrangement consisting of a bore and an engaging journal, fixed preferably on the chassis or the rigid axle.
[0007] It is further preferred that the actuating unit has a fixing element, which fixes the actuating unit perpendicular to the transverse direction movably relative to the reference system. To put it differently, the fixing element, insofar as this is possible ensures that the actuating unit is secured against displacement along the transverse direction. At the same time, however, it allows for a displacement of the actuating unit relative to the reference system perpendicular to the transverse direction. A preferred arrangement of the actuating unit, pivotable and displaceable perpendicular to the transverse direction, makes it possible that in the case of a steering deflection of two lever elements fixed to the tie rod unit, the respective second turning points may be displaced in different directions perpendicular to the transverse direction, wherein the actuating unit guiding the tie rod unit is pivoted in relation to the reference system and displaced relative to the reference system perpendicular to the transverse direction. It has proven to be expedient to secure the actuating unit by means of the fixing region only against displacement along the transverse direction, wherein a pivoting movement and a displacement perpendicular to the transverse direction remain possible. The pivoting movement of the fixing element, and the fixing point moving hence on a circular path between the fixing element and the actuating unit indeed leads to a slight, essentially negligible movement of the actuating unit along the transverse direction, which is taken into account in the layout of the steering arrangement. The definition of the immovability of the actuating unit along the transverse direction therefore neglects merely this point.
[0008] In an alternatively preferred embodiment, the tie rod unit has a joint or hinge, which pivotably fixes a first tie rod section and a second tie rod section to each other, wherein the first tie rod section is preferably guided in the actuating unit and secured against displacement transverse or perpendicular to the transverse direction, and wherein the actuating unit is fixed immovably and secured against pivoting relative to the reference system. Alternatively to the arrangement of the actuating unit, which is pivotable or displaceable perpendicular to the transverse direction, it may also be preferred to provide at least one, particularly preferably two joints on the tie rod unit, which pivotably fix one respective second tie rod section to the first tie rod section. Here, the path components, which are caused by a pivoting movement of the lever element perpendicular to the transverse direction, are compensated by pivoting movements of the second tie rod sections relative to the first tie rod section, and the first tie rod section displaces exclusively along the transverse direction, and no pivoting arrangement of the actuating unit is necessary. Particularly preferably, the joint is designed as a ball-and-socket joint, where a ball socket or joint socket preferably provided on the first tie rod section accommodates a joint head or ball section preferably provided on the second tie rod unit and mounts it pivotably. Particularly preferably, in this embodiment, the actuating unit may be fixed immovably on the vehicle axle or the vehicle frame, wherein advantageously further complicated arrangements and components are thus avoided and a high service life and reliability or stability of the steering arrangement are ensured.
[0009] Further preferably, the second tie rod section has an extension, which is in a relationship of 0.3-1.5, preferably 0.5-1, and particularly preferably 0.7-0.8 to the maximum displacement path of the tie rod unit along the transverse axis. The larger said relationship, the larger the second tie rod section relative to the maximum displacement path of the tie rod unit along the transverse axis, wherein it is in particular preferred that there is a smaller deflection or a smaller change of angle in the pivoting movement of the second tie rod section to the first tie rod section, and respective force components, which act perpendicular to the transverse axis on the first tie rod section and, thus, on the actuating unit, are reduced. When the extension of the second tie rod section is too large, however, an increased building space requirement or an insufficiently compact design of the steering arrangement may be disadvantageous. It has been shown that steering arrangements having a preferred relationship of 0.3-1.5 of the length of the second tie rod section relative to the maximum displacement of the tie rod unit along the transverse axis reliably fulfill the compactness requirements while at the same time the transverse forces on the tie rod unit or on the first tie rod section are minimized.
[0010] Further preferably, the lever element has a lever arm extending between the first and the second turning points, wherein in the neutral position of the lever arm, the straight line running along the lever arm is directed or aligned pivoted at an angle to the transverse direction of the reference system, and wherein the angle is preferably larger than 90°. The non-perpendicular alignment of the lever arm of the lever element in the neutral position preferably serves to create the so-called steering trapezoid. To this end, the straight line running along the lever arm is preferably arranged pivoted at an angle of more than 90° from the transverse axis, opposite the straightforward driving direction of the commercial vehicle, wherein, as a consequence, the respective steering element lying outside in the traveled curve is deflected less from the neutral position than the respective steering element lying inside. To put it differently, the angle has to be spanned from the transverse axis or a parallel to the transverse axis in an arc running opposite the straightforward driving direction up to the straight line, intersecting between the first and the second turning point. For example, in the case of a trailing axle, depending on whether the second turning point is arranged in the straightforward driving direction behind or, in relation to the arrangement in the commercial vehicle, behind the first turning point or vice versa, the angle is in each case defined. In case the second turning point is arranged behind the first turning point in the straightforward driving direction, the angle is measured from the transverse axis or the end opposite the straightforward driving direction of the transverse axis facing outwards in the direction of the preferably provided wheels of the commercial vehicle up to the straight line running along the lever arm. In this case, the shorter one of the two parallels of the steering trapezoid is limited by the first turning points, and the longer one is limited by the second turning points. Preferably, the angle of pivoting of the lever arm relative to the transverse axis is in a range of 91°-160°, particularly preferably 95°-420°, and most preferably it is about 100°-115°. It has been shown that said angle ranges particularly preferably allow for an optimum driving comfort, an optimum driving safety and a reduced wear on the tires for various vehicle lengths or for various distances of the wheel suspension systems provided with a steering arrangement from the wheel suspension systems disposed therebehind or in front thereof.
[0011] Preferably, the first turning point is spaced apart from the second turning point by a lever length, wherein the tie rod unit is displaceable within a maximum displacement path along the transverse axis, and wherein the relationship of the lever length to the maximum displacement path is in a range of 0.7-1.3, preferably 0.85 to 1.1, and particularly preferably it is about 0.9-1. The relationship of the lever length to the maximum displacement path of the tie rod unit makes it particularly preferably possible to adjust the possible pivoting range of the lever element. In the case of a small relationship of the lever length to the maximum displacement path, a small pivoting range of the lever element for a given displacement path of the tie rod unit has to be expected. To put it differently, this means that the steering angle of the vehicle is smaller and that the turning radius or turning circle for a given displacement path of the tie rod unit increases. By contrast, when choosing a large relationship of the lever arm to the displacement path of the tie rod unit, it is advantageous that a relatively small force on the actuating unit reliably pivots the wheel of the commercial vehicle by means of the large lever length. If, however, the relationship is kept small, this tends to require larger adjusting forces on the actuating unit. Advantageously, corresponding to the requirement on the turning circle of the vehicle and the forces on the actuating unit required by the weight of and the load on the steering arrangement, an optimum relationship of the lever length to the maximum displacement path of the tie rod unit may be chosen.
[0012] Further preferably, the active part of the actuating unit has a valve arrangement, by means of which a working fluid can be supplied and discharged, in order to transmit a steering force to the tie rod unit via a piston element, wherein, when the valve arrangement is closed, the tie rod unit is secured against displacement along the transverse axis. Preferably, the valve arrangement comprises bores on the actuating unit, on which preferably tubes or hoses may be attached, which in turn lead to a pump or control unit with respective valves. The most important function of the valve arrangement is the supply and the discharge of working fluid in the cylindrical region of the actuating unit, in which a piston element fixed to the tie rod unit is displaced since different pressures are generated in the working fluid in front of and behind the piston element within the actuating unit. By preventing or blocking the supply or discharge of the working fluid into the actuating unit, it is simultaneously blocked or prevented that the piston element moves within the cylindrical region of the actuating unit and, thus, that the tie rod unit displaces relative to the actuating unit. Advantageously, the active part of the actuating unit thus ensures a reverse lock of the steering arrangement.
[0013] Particularly preferably, the damping part of the actuating unit is integrated into the active part and preferably comprises a damping valve arrangement, wherein the damping valve arrangement and/or the valve arrangement of the active part contribute to damping the displacement of the tie rod unit. In order to realize a particularly compact design of the steering arrangement, it may be preferred to integrate the damping part of the actuating unit into the active part and to use the valve arrangement provided already for the active part also for damping vibrations or oscillations occurring on the steering arrangement. In addition to said valve arrangement, it may be further preferred to provide on the actuating unit damping valves connected in parallel, which irrespective of the function of the active part, such as a possible blocking of the working fluid flow when the reverse lock is set, allow for a damping of vibrations or shocks on the steering arrangement. Alternatively preferably, the damping part may also be provided fluid-mechanically separate from the active part, wherein advantageously also various working fluids, such as air or similar compressible media, may be used in order to damp vibrations or shocks.
[0014] Preferably, the restoring part of the actuating unit is spatially and functionally separated from the active part and/or the damping part of the actuating unit. The restoring part is spatially separated from the active part or from the damping part of the actuating unit in particular when the restoring part is arranged in a separate section of the actuating unit adjacent to the active part and/or to the damping part, wherein the restoring element preferably provided in the restoring part engages a specifically provided engagement section on the tie rod unit. An advantage of this embodiment is that the restoring part may be maintained and mounted or dismounted without opening or disrupting working fluid circuits possibly provided in the active part and/or the damping part.
[0015] Alternatively, in order to achieve a compact design, the restoring part may be integrated into the active part and/or into the damping part.
[0016] Further according to the invention is a restoring part, comprising a first cylinder section, a second cylinder section, a third cylinder section, a fourth cylinder section and a restoring element, wherein at least the first three cylinder sections are designed in the shape of hollow cylinders, wherein the third and the fourth cylinder sections and the restoring element are arranged essentially within the first and the second cylinder sections and displaceable along a restoring axis relative to the first and second cylinder sections, wherein the second cylinder section is displaceable along the restoring axis into the first cylinder section, and the fourth cylinder section, is displaceable along the restoring axis into the third cylinder section, wherein the restoring element with a first end thereof rests against a first limit stop of the third cylinder element, and with its opposing second end rests against a second limit stop of the second cylinder element, wherein while or when or after the fourth cylinder element is/has been displaced along the restoring axis in the direction of the first cylinder element, a second limit stop of the fourth cylinder element supports the second limit stop of the second cylinder element against the restoring element, and the third cylinder element rests against a first limit stop of the first cylinder element, wherein while or when or after the fourth cylinder element is/has been displaced along the restoring axis away from the first cylinder element, a first limit stop of the fourth cylinder element displaces the third cylinder element via a first limit stop in the direction of the fourth limit stop, while a second limit stop of the first cylinder element supports the second cylinder element via the first limit stop thereof against the restoring element, wherein the restoring element while or when or after the first cylinder element is/has been displaced relative to the fourth cylinder element along the restoring axis a restoring force is established between the second and the third cylinder elements. Following the common inventive idea of a compact design, it is particularly preferred that the restoring part comprises interleaved cylinder elements, which may be telescoped into each other in a particularly space-saving manner when the spring ranges are sufficiently large. Thus, the restoring part, apart from the preferred integration of the damping part and of the active part into the actuating unit, for example, makes an essential contribution to the compact design of the steering arrangement on the whole. According to the invention, the restoring part takes over to restore the steering arrangement in the straightforward driving direction or neutral position. To this end, there is provided a restoring element, which in the case of a deflection of the steering arrangement from this neutral position is subjected to pressure in the restoring part, wherein a restoring force acts, which seeks to displace the steering arrangement back in the neutral position. Preferably, the first cylinder element is arranged immovably, indirectly or directly relative to the chassis of the commercial vehicle or to the rigid part of a steering axle, while the fourth cylinder element is arranged indisplaceably or immovably relative to the moving parts of the steering arrangement. According to the invention, a steering deflection of the steering arrangement causes the restoring part to be compressed or extended, wherein the first and the fourth cylinder elements carry out a relative movement with respect to each other. Characteristic of the restoring part according to the invention are the compact design and the ability of the restoring element to be subjected only to pressure, both when the restoring part is compressed and when it is extended. Thus, the service life or the number of possible load cycles of the restoring element, such as a spiral spring, can be significantly increased. The compact design results from the arrangement according to the invention of the four cylinder elements and the limit stops provided on the respective cylinder elements. The limit stops are preferably formed as collars protruding inwards or outwards and serve either for supporting the restoring element or for supporting or carrying a corresponding limit stop of a cylinder element, which is to be supported or entrained in one direction. Preferably, the restoring element is pretensioned between the second and the third cylinder elements, also while the steering arrangement is in the neutral position.
[0017] Advantageously, the restoring element essentially completely fills the extension or building length along or parallel to the restoring axis occupied by the second cylinder element and the third cylinder element. The building length defined by the second and the third cylinder elements preferably corresponds to the sum of the overall extension of both cylinder elements less the length, along which the second and the third cylinder elements overlap, and less the extension of the second limit stop of the second cylinder element and the extension of the first limit stop of the third cylinder element along the restoring axis. Thus, “essentially” means in this context that from the overall extension of building length occupied by the second and third cylinder elements together, merely the extension of the two outer limit stops is deducted in order to come to the preferred extension of the restoring element. This preferred design of the restoring part may lead to a particularly good space utilization by the restoring element, and in the case of a compact design of the restoring element and, thus, of the steering arrangement, particularly large spring ranges are available.
[0018] Preferably, the first collar of the third cylinder comes to rest against the first limit stop of the first cylinder element, while the restoring part is compressed. In order to achieve a compact and, thus, weight-saving design of the restoring part, it is preferred to arrange the first limit stop of the third cylinder element as far away as is possible from the second limit stop of the fourth cylinder element and, thus, to utilize the extension or the available length of the restoring part along the restoring axis essentially completely with the restoring element. Thus, in the case of a comparatively short overall length of the restoring part, a rather large, maximum possible spring range of the restoring element results. Here, the relationship of the maximum possible spring range, i.e. the amount or travel, by which the spring element may be compressed at most, to the overall length of the restoring part in the neutral position is preferably 0.3 to 0.8, particularly preferably 0.4 to 0.7, and most preferably it is about 0.5 to 0.6. The overall length of the restoring part is preferably the distance of the first limit stop of the first cylinder element from the second limit stop of the fourth cylinder element in the neutral position. As a matter of course, the described relationship depends on the geometry of the restoring element, in particular the relationship of the wire thickness of a preferably used spiral spring to the distance of the coils from each other along the restoring axis.
[0019] Preferably, the restoring part has a support unit, comprising a first support element and a second support element, wherein the first support element is fixed to the first cylinder element, and the second support element is fixed to the fourth cylinder element, wherein one of the support elements has a recess, into which the respective other support element may be inserted along the restoring axis at least in sections, so that it is prevented that the first cylinder element pivots relative to the fourth cylinder element along the restoring axis. The support unit protects the restoring part preferably against buckling when subjected to pressure along the restoring axis. Preferably, the first support element telescopically engages the second support element, so that transverse to the restoring axis there is a form-fit between the two support elements, which essentially prevents a displacement of the first support element relative to the second support element transverse to the restoring axis. “Essentially” in this context means that within the framework of the clearance due to production there may be smaller displacements also transverse to the restoring axis.
[0020] According to the invention, there is provided a steering system combining the features of the above-described steering arrangement and the restoring part, which is also according to the invention. Said steering system has a preferred, compact design, since the compact arrangement of the components of the actuating unit may be combined with a compact restoring part.
[0021] Further advantages and features of the present invention become apparent from the following description with reference to the appended Figures. Individual features of the preferred embodiments shown may be combined within the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The Figures show:
[0023] FIG. 1 shows a view of a preferred embodiment of the steering arrangement according to the invention in the neutral position,
[0024] FIG. 2 shows a preferred embodiment of the steering arrangement according to the invention with joints,
[0025] FIG. 3 shows a preferred embodiment of the actuating unit with inserted tie rod unit,
[0026] FIG. 4 shows a view of a preferred embodiment of the steering arrangement according to the invention in the neutral position, and
[0027] FIG. 5 shows a sectional view of a preferred embodiment of the restoring part according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] FIG. 1 shows a preferred embodiment of the steering arrangement according to the invention, wherein an actuating unit 4 is indirectly fixed to the rigid axle 10 of a commercial vehicle by means of a fixing element 45 . The fixing element 45 secures the actuating unit 4 in particular against displacement relative to a reference system 1 along a transverse axis Q. The actuating unit 4 has a restoring part 41 , an active part 42 and a damping part 43 , wherein in the preferred embodiment shown the active part 42 and the damping part 43 are designed integrally. Alternatively preferably, the damping part 43 may be designed spatially and functionally separate from the active part 42 . Preferably, a tie rod unit 2 passes through the actuating unit 4 , wherein the tie rod unit 2 is preferably guided through the actuating unit 4 . Preferably, the tie rod unit 2 , at the distal ends thereof, directly or indirectly engages a second turning point 82 and is pivotably fixed in said respective point to a respective lever element 6 . In the second turning points 82 , there are particularly preferably provided ball bearings or bushings, which allow for a slight rotating movement of the tie rod unit 2 relative to the lever element 6 . The lever element 6 in turn is fixed to the rigid axle 10 rotatably or pivotably in a first turning point 81 immovable to the reference system 1 . Preferably, the lever element 6 has a lever arm 62 and further devices, preferably for rotatably mounting a wheel or a wheel suspension of a commercial vehicle. The steering arrangement shown in the Figure, and in particular the lever element, is designed like a pusher axle known from prior art, wherein the axis of rotation of the wheel to be attached to the lever element 6 is arranged behind the first turning point 81 . Furthermore, the embodiment of the steering arrangement according to the invention shown in the Figure is in the neutral position, which particularly preferably is characterized in that the axes of rotation of the wheel suspension preferably attached to the lever element 6 are aligned parallel or collinear to the transverse direction Q of the reference system 1 . To put it differently, the steering deflection of the steering arrangement in the neutral position is zero. Particularly preferably, in order to adjust a certain relative steering angle, the straight line running along the lever arm 62 of the lever element 6 is pivoted by an angle α with reference to the transverse direction Q. Relative steering angle in this context means a larger steering angle of the lever element 6 lying inside during cornering, with reference to the curve traveled, in comparison to the lever element 6 lying outside. In the embodiment shown in the Figure, when a left curve is traveled, the wheel suspension shown on the right in the Figure accordingly has a larger steering angle than the left one. The two first turning points 81 and the two second turning points 82 preferably span not a rectangle but a trapezoid, usually also referred to as steering trapezoid. The larger the angle α, the larger the relative steering angle may preferably be set. The lever arm 62 of the lever element 6 preferably has a length L, which is in a preferred relationship to the maximum possible path of displacement s max of the tie rod unit 2 of 0.7-1.3, preferably of 0.85-1.1, and particularly preferably of 0.9-1. Furthermore, the steering arrangement according to the invention, depending on the available building space on the commercial vehicle, seen in the straightforward driving direction F, may be arranged behind the rigid axle 10 .
[0029] FIG. 2 shows a preferred embodiment of the steering arrangement according to the invention, wherein the tie rod unit 2 particularly preferably has two joints 24 , which pivotably connect a first tie rod section 21 to a respective second tie rod section 22 , wherein a displacement of the tie rod unit 2 along the transverse direction Q is possible without pivoting or displacing the first tie rod section 21 perpendicular or transverse to the transverse direction Q. Preferably, the actuating unit 4 , which guides the first tie rod section 21 , can be arranged fixedly and immovably on the rigid axle 10 . Preferably, it is possible to avoid fixing the actuating unit 4 in an expensive and time-consuming manner by means of a fixing element 45 , as is shown in FIG. 1 , and it is possible to choose a more robust design of the steering arrangement. The second tie rod sections 22 have a preferred extension s 22 , which is in a relationship to the maximum displacement path s max of the tie rod unit 2 or of the first tie rod section 21 of preferably 0.3-1.5, particularly preferably of 0.5-1, and most preferably of 0.7-0.8. The extension s 22 of the second tie rod sections 22 is measured in particular from the turning point of the joint 24 up to the second turning point 82 . Since the steering arrangement is not in the neutral position, the angle α is measured not from a parallel of the transverse axis Q, but from the axis of rotation of wheels (not shown) preferably mounted on the steering arrangement to the straight line running along the lever arm 6 . In the embodiment shown in FIG. 2 , the angle α is preferably only slightly larger than 90°.
[0030] FIG. 3 shows a detailed view of the tie rod unit 2 already shown in FIG. 2 with a first tie rod section 21 , two joints 24 and two second tie rod sections 22 . In this embodiment, the actuating unit 4 can be fixed immovably on a rigid axle 10 , which is not shown, wherein the two fixing sections 46 may simultaneously contain the supply and discharge channels for the working fluid in of the active part 42 or the damping part 43 of the actuating unit 4 . As is shown in the Figure, in the restoring part 41 , there is provided a restoring element, wherein the latter is maximally compressed in the shown position of the tie rod unit. In the Figure, the restoring unit 2 is thus maximally deflected to the left relative to the actuating unit 4 or relative to the reference system 1 along the transverse axis Q.
[0031] FIG. 4 shows a preferred embodiment of the steering arrangement according to the invention, which is designed as a trailing axle, in the neutral position. The first turning points 81 of the steering arrangement, in the straightforward driving direction F of the commercial vehicle, are preferably arranged in front of the wheel bearings of the wheels, which are not shown, i.e. above said wheel bearings in the Figure, through which bearings the transverse axis Q runs in the shown position. Furthermore, the second turning points 82 in the straightforward driving direction F of the commercial vehicle are arranged in front of the first turning points 81 , in the Figure accordingly above the first turning points 81 . The above-described definition of the angle α, in the neutral position facing from a parallel to the transverse axis Q outwards in the direction of the wheels (not shown) of the commercial vehicle, opposite the straightforward driving direction F up to the straight line running along the lever arm 6 , results for the present embodiment in that the lever arms 6 describe an open V. The longer one of the parallels of the steering trapezoid is accordingly limited by the second turning points 82 .
[0032] As a matter of course, the measured angles are defined between the projections of the spatially arranged straight line and points on the viewer plane of the respective Figure. FIG. 5 shows a sectional view of a preferred embodiment of the restoring part 41 according to the invention. The restoring part comprises four cylinder elements 411 , 412 , 413 and 414 , which preferably are designed in the shape of hollow cylinders or bushes and which preferably have inner and outer diameters differing from those of the respective other cylinder elements. Preferably, the second cylinder element 412 may be inserted or moved at least in sections into the first cylinder element 411 , and the fourth cylinder element 414 may be inserted or moved at least in sections into the third cylinder element 413 . Further preferably, the third and the fourth cylinder elements 413 , 414 are at least in certain sections arranged in the hollow space spanned by the first and the second cylinder elements 411 , 412 . The first cylinder element 411 has a first limit stop 411 a , which preferably is designed as a bottom or end plate. The first limit stop 411 a of the first cylinder element 411 with its outwards facing surface is connected to further parts of the actuating unit 4 (not shown) or to rigid sections of the commercial vehicle. Furthermore, on the first limit stop 411 a of the first cylinder element 411 there is preferably fixed the first support element 417 of the support unit 419 , by a screwed joint (shown) or by a welded joint, for example. The second cylinder element 412 has a second limit stop 412 b , which preferably is designed as a cap with a recess, wherein through the recess the fourth cylinder element 414 passes and may slide relative to the second cylinder element 412 . When the restoring part 41 is compressed, the second limit stop 412 b of the second cylinder element 412 rests against a second limit stop 414 b of the fourth cylinder element 414 , so that the end of the restoring element 416 shown at the right-hand side of the Figure is displaced towards the left. The left end of the restoring element 416 rests against the first limit stop 413 a of the third cylinder element 413 , which preferably rests against the first limit stop 411 a of the first cylinder element 411 . By compressing the restoring element 416 a restoring force is established by the restoring element between the second limit stop 412 b of the second cylinder element 412 and the first limit stop 413 a of the third cylinder element 413 , and thus indirectly between the fourth and the first cylinder elements 414 , 411 . When the restoring element 41 is extended or when the distance between the fourth cylinder element 414 and the first cylinder element 411 is enlarged, the fourth cylinder element 414 slides towards the right in the recess in the second limit stop 412 b of the second cylinder element 412 . While the first limit stop 414 a of the fourth cylinder element 414 supports the second limit stop 413 b of the third cylinder element 413 and, thus, pulls the third cylinder element 413 towards the right, the second cylinder element 412 via the first limit stop 412 a thereof, which engages the second limit stop 411 b of the first cylinder element 411 , is secured against displacement to the right in the Figure, relative to the first cylinder element 411 . By displacing the third cylinder element 413 along the restoring axis A relative to the second cylinder element 412 , the restoring element 416 is compressed between the first limit stop 413 a of the third cylinder element 413 and the second limit stop 412 b of the second cylinder element 412 and exerts a restoring force on both limit stops 413 a and 412 b , which causes the restoring part 41 to seek its neutral position, in which the restoring element 416 has its largest extension along the restoring axis A. As a matter of course, the restoring part 41 shown in FIG. 5 may be used in the embodiment of the actuating unit 4 shown in FIG. 3 , for example, wherein either the first limit stop 411 a of the first cylinder element 411 or the second limit stop 414 b of the fourth cylinder element 414 is fixed to the tie rod unit, and the respective other limit stop is connected to the housing of the actuating unit 4 . Also the embodiments of the steering arrangement according to the invention shown in FIGS. 1 and 2 , may be enriched by a compact design by installing the restoring part 41 shown in FIG. 5 .
[0000]
List of reference signs
1
reference system
2
tie rod unit
4
actuating unit
6
lever element
10
rigid axle
21
first tie rod unit
22
second tie rod unit
24
joint
41
restoring part
42
active part
43
damping part
45
fixing element
46
fixing section
62
lever arm
81
first turning point
82
second turning point
411
first cylinder element
411a
first limit stop
411b
second limit stop
412
second cylinder element
412a
first limit stop
412b
second limit stop
413
third cylinder element
413a
first limit stop
413b
second limit stop
414
fourth cylinder element
414a
first limit stop
414b
second limit stop
416
restoring element
417
first support element
418
second support element
419
support unit
A
restoring axis
α
angle
F
straightforward driving direction
L
length
Q
transverse axis
s max
maximum displacement path
s 22
extension of the second tie rod sections | The present invention relates to a steering arrangement, a restoring part and a steering system, that includes a tie bar unit, an actuating unit and a lever element, the lever element being fixed in a pivotable manner at a first turning point immovably disposed in a reference system, wherein the actuating unit has a restoring part, an active part and a damping part and is secured against displacement along a transverse axis relative to the reference system, at least one of the parts exerting a force on the tie rod unit to displace the tie rod unit along the transverse axis or to secure it against displacement, wherein the tie rod unit is pivotably fixed at a second turning point on the lever element and therefore displacement of the tie rod unit along the transverse axis leads to a pivoting movement of the lever element about the first turning point. | 1 |
The invention relates to a method of manufacturing a fluorine-doped silica powder, the doped silica being for making optical fiber preforms.
BACKGROUND OF THE INVENTION
Doping is an operation which consists in incorporating atoms or molecules in a material in order to modify the properties of the material. For example, in the field of optical fibers, dopants are incorporated in silica in order to modify its refractive index. The dopant can then be germanium if it is desired to increase the refractive index of the silica, or fluorine if it is desired on the contrary to lower the index.
The silica used can be natural silica or synthetic silica. Nevertheless, in the field of optical fibers, it is synthetic silica that is used most often. Synthetic silica is silica that is obtained by chemical synthesis, e.g. by oxidation of a silica-precursor gas in the presence of heat, for example silicon tetrachloride SiCl 4 . That reaction leads to a powder that is very pure with a grain size that is very fine, i.e. a grain size lying in the range 0.1 nanometers (nm) to 100 nm, and as a result the powder has a high specific surface area. Such a silica powder is known as “soot”.
Silica soot can be used, for example, to fabricate a preform by the method of vapor axial deposition (VAD) or outside vapor deposition (OVD).
Document JP 62252335 describes a method of fabricating a preform in which the silicon compound is hydrolyzed in the presence of silicon oxifluoride, thus leading to a deposit of fluorine-containing silica soot which is subsequently vitrified.
Those methods are well known to the person skilled in the art of optical fibers, and they are not described in greater detail below.
Silica soot can also be transformed using the method described in document EP 0 578 553. The resulting silica grains can then be deposited and vitrified in order to increase the diameter of primary preforms manufactured by the modified chemical vapor deposition (MCVD) method.
In order to manufacture those silica grains, the particles of soot are agglomerated by a sol-gel method so as to form granules, and the granules are then densified by heating, which enables the pores that exist between the various particles making them up to be eliminated so that the resulting grains are dense. In general, such grains are of a size that is greater than 1 micron (μm). The term “silica granule” is used to designate a porous particle of silica at an intermediate stage in the fabrication of densified silica grains.
It is possible to perform the operation of densifying granules under an atmosphere containing a gas that is a precursor of the desired dopant. Thus, in order to fluorinate silica granules, densification is performed under an atmosphere containing a fluorine-containing gas such as sulfur hexafluoride SF 6 or silicon tetrafluoride SiF 4 . The granules of silica are placed in a crucible which is in turn placed in an oven so as to raise it to the temperature that enables densification to take place, the oven being fed with a gas that is a precursor of the desired dopant. Doping takes place by diffusion and reaction of the dopant molecules in the silica granules, thereby leading to the formation of complex molecules of the SiO 2−x F 2x type. The method is performed at high temperature, i.e. around 1400° C.
An alternative device enabling moving granules to be densified in the presence of a fluorine-containing gas is described in FR 2 749 005.
Those methods give rise to a certain number of problems.
The first drawback lies in the aggressivity of fluorine-containing gases. The high corrosivity of the fluorine-containing gases that are used at high temperature gives rise to massive corrosion of the ovens, thereby leading to high maintenance costs. Another problem is the handling of such gases and their treatment or recovery that is required because of their toxicity. Finally, these gases, and in particular SiF 4 , are of non-negligible costs.
Their second drawback lies in the lack of uniformity of the doping that is achieved in this way, which lack of uniformity is associated with the way the fluorine-containing reagent diffuses within the powder being treated, particularly when the powder is deposited in a crucible.
OBJECT AND SUMMARY OF THE INVENTION
The object of the present invention thus consists in providing a method of fabricating a powder of dense fluorine-doped silica grains that enables the corrosion of equipment to be reduced considerably and that does not present the above-mentioned drawbacks.
The present invention thus provides a method of fabricating a fluorine-doped silica powder for making optical fiber preforms, the method comprising the steps of:
mixing a solid fluorine compound with silica granules having a specific surface area greater than 30 square meters per gram (m 2 /g) thermally decomposing said solid fluorine compound; and densifying the resulting doped silica granules to obtain doped silica grains.
The silica granules are mixed with the desired quantity of the solid fluorine compound and they are introduced into a suitable receptacle. In one implementation, the mixture of silica granules and of solid fluorine compound contains 1% to 30% and in particular 2% to 12% of solid fluorine compound.
It is preferable to use a crucible made of a material such as quartz that withstands fluorine at the treatment temperature.
The oven used for the method can be a horizontal rotary oven made of quartz, which presents the additional advantage of being capable of operating continuously. A static oven with a quartz reactor could also be used. It can be placed horizontally or vertically, but it is preferable for it to be placed vertically. This presents the advantage of minimizing the exchange area between the powder and the atmosphere, and thus of minimizing evaporation of SiF 4 . In any event, the oven is continuously swept with an inert gas such as helium.
It is preferable to use granules of synthetic silica presenting a specific surface area lying in the range 30 m 2 /g to 200 m 2 /g. It is assumed that the released fluorinating agent preferentially attacks the OH sites of the silica. The number of these sites depends on the specific surface area of the silica. Thus, it can be expected that a very finely divided silica enables a higher degree of fluorine doping to be achieved. Thus, when it is desired to obtain fluorine-doped silica, it is preferable to use silica granules having a high specific surface area. A specific surface area greater than 30 m 2 /g is therefore advantageous.
In an implementation, the solid fluorine compound is ammonium bifluoride. Nevertheless, it is also possible to envisage using other solid fluorine compounds that are thermally unstable.
Furthermore, the method is preferably carried out at moderate temperature, i.e. lower than 1450° C., and preferably in the range 250° C. to 600° C. The decomposition temperature is preferably less than or equal to 600° C., in particular it is less than or equal to 425° C. The fluorine compound used decomposes at moderate temperature, i.e. at lower than 1450° C., preferably lower than 600° C. It is found that even at 250° C., the fluorine-containing reagent diffuses quickly through the granules. The length of time the decomposition temperature is maintained may be less than 1 hour (h), and it preferably lies in the range 15 minutes (min) to 60 min.
In an implementation, the mixture is maintained at the decomposition temperature for a duration of 15 min to 60 min.
The densification step itself is known. A conventional oven, e.g. made of graphite, can be used, thereby constituting an additional advantage of the method of the invention. The densification treatment is preferably also performed under an inert atmosphere.
In an implementation, the method is performed continuously.
The first advantage of the method of the invention is that potentially corrosive compounds are given off at moderate temperature, thereby considerably reducing equipment wear.
The second advantage of the method of the invention is that by causing the fluorinating agent to be given off in situ, it is possible to ensure that fluorine is incorporated uniformly in the silica granules.
DETAILED DESCRIPTION OF THE INVENTION
The invention is illustrated in greater detail by the following examples.
Flourination
EXAMPLE 1
94 grams (g) of synthetic silica granules having a specific surface area of 50 m 2 /g and 6 g of ammonium bifluoride (6%) were introduced into a quartz crucible having a diameter of 50 millimeters (mm) and a height of 144.5 mm. The crucible was introduced into a quartz reactor placed in a vertical oven. The mixture was then raised over 20 min to 250° C. while being swept with helium, and its temperature was then maintained for 15 min. Thereafter, it was allowed to cool to ambient temperature (duration 150 min).
A sample was subsequently put into solution by alkaline sintering and its fluorine content was assayed by ionometry. The results obtained are given in Table 1.
EXAMPLE 2
91 g of synthetic silica granules identical to those of Example 1 and 9 g of ammonium bifluoride (9%) were introduced into a crucible identical to that of Example 1. The crucible was introduced into a quartz reactor placed in a vertical furnace. The mixture was then heated over 30 min to 425° C. while being swept with helium, and thereafter the temperature was maintained for 15 min. The temperature was then allowed to cool down to ambient (duration 150 min).
The sample was assayed as in Example 1. There results obtained are given in Table 1.
EXAMPLE 3
92 g of synthetic silica granules identical to those of Example 1 and 9 g of ammonium bifluoride (9%) were introduced into a crucible identical to that of Example 1. The crucible was introduced into a quartz reactor placed in a vertical furnace. The mixture was then heated over 75 min to 600° C. while being swept with helium, and thereafter the temperature was maintained for 60 min. The temperature was then allowed to cool down to ambient (duration 150 min).
The sample was assayed as in Example 1. There results obtained are given in Table 1.
EXAMPLE 4
88 g of synthetic silica granules identical to those of Example 1 and 12 g of ammonium bifluoride (12%) were introduced into a crucible identical to that of Example 1. The crucible was introduced into a quartz reactor placed in a vertical furnace. The mixture was then heated over 75 min to 600° C. while being swept with helium, and thereafter the temperature was maintained for 15 min. The temperature was then allowed to cool down to ambient (duration 150 min).
The sample was assayed as in Example 1. There results obtained are given in Table 1.
EXAMPLE 5
94 g of synthetic silica granules identical to those of Example 1 and 6 g of ammonium bifluoride (6%) were introduced into a crucible identical to that of Example 1. The crucible was introduced into a quartz reactor placed in a vertical furnace. The mixture was then heated over 75 min to 600° C. while being swept with helium, and thereafter the temperature was maintained for 15 min. The temperature was then allowed to cool down to ambient (duration 150 min).
The sample was assayed as in Example 1. There results obtained are given in Table 1.
EXAMPLE 6
56.40 g of synthetic silica granules identical to those of Example 1 and 3.60 g of ammonium bifluoride (6%) were weighed out into a crucible made from a quartz tube having a diameter of 46 mm that was truncated and closed flat at each end. The mixture was introduced into a quartz reactor placed in a horizontal oven. The mixture was then heated over 75 min to 600° C. while being swept with helium, and the temperature was then maintained for 15 min. Thereafter it was allowed to cool to ambient temperature.
The sample was assayed as mentioned in Example 1. The results are given in Table 1.
EXAMPLE 7
58.56 g of synthetic silica granules identical to those of Example 1 and 1.44 g of ammonium bifluoride (2.4%) were weighed out into a crucible identical to that of Example 6. The mixture was introduced into a quartz reactor placed in a vertical oven. The mixture was then heated over 75 min to 600° C. while being swept with helium, and the temperature was maintained for 60 min. Thereafter it was allowed to cool to ambient temperature.
A sample was assayed as mentioned in Example 1. The results are given in Table 1.
EXAMPLE 8
57.48 g of synthetic silica granules identical to those of Example 1 and 2.52 g of ammonium bifluoride (4.2%) were weighed out into a crucible identical to that of Example 6. The mixture was introduced into a quartz reactor placed in a vertical oven. The mixture was then heated over 30 min to 425° C. while being swept with helium, and the temperature was maintained for 37.5 min. Thereafter it was allowed to cool to ambient temperature.
A sample was assayed as mentioned in Example 1. The results are given in Table 1.
EXAMPLE 9
56.40 g of synthetic silica granules identical to those of Example 1 and 3.60 g of ammonium bifluoride (6%) were weighed out into a crucible identical to that of Example 6. The mixture was introduced into a quartz reactor placed in a vertical oven. The mixture was then heated over 20 min to 250° C. while being swept with helium, and the temperature was maintained for 60 min. Thereafter it was allowed to cool to ambient temperature.
A sample was assayed as mentioned in Example 1. The results are given in Table 1.
EXAMPLE 10
58.56 g of synthetic silica granules identical to those of Example 1 and 1.44 g of ammonium bifluoride (2.4%) were weighed out into a crucible identical to that of Example 6. The mixture was introduced into a quartz reactor placed in a vertical oven. The mixture was then heated over 20 min to 250° C. while being swept with helium, and the temperature was maintained for 15 min. Thereafter it was allowed to cool to ambient temperature.
A sample was assayed as mentioned in Example 1. The results are given in Table 1.
TABLE 1 fluorination NH 4 F, HF Fluorine Temperature Duration introduced incorporated Example [° C.] [min] [%] [ppm] 1 250 15 6 19500 2 425 15 9 11000 3 600 60 9 9800 4 600 15 12 13500 5 600 15 6 11400 6 600 15 6 8100 7 600 60 2.4 5500 8 425 37.5 4.2 7390 9 250 60 6 8900 10 250 15 2.4 7600
DENSIFICATION
EXAMPLE 11-15
The fluorine-doped silica granules obtained in Examples 1 to 5 were densified at 1450° C. in an alumina tube oven while being swept with helium in a crucible identical to that used during fluorination. The heating program was as follows:
free heating up to 1100° C.; 140° C./h from 1100° C. to 1300° C.; 85° C./h from 1300° C. to 1400° C.; 50° C./h from 1400° C. to 1450° C.; 1450° C. for 15 min; and cooling down to a temperature of 200° C. at the outlet from the oven for cooling down to ambient temperature.
After the operation, a powder comprising dense grains of fluorine-doped silica was obtained suitable for use in fabricating optical fiber preforms. Fluorine content was determined by ionometric assay after being put into solution by alkaline sintering. The results are given in Table 2.
TABLE 2
densification
F content in the
F content in the
Example
granules [ppm]
grams [ppm]
11
19500
3980
12
11000
5240
13
9800
3800
14
13500
3730
15
11400
4400
The results show clearly that the method of the invention enables synthetic silica to be doped with fluorine at low temperature. The resulting powder of dense silica grains presents a fluorine content that can be as high as 5000 parts per million (ppm) of fluorine after densification.
This method reduces the corrosion observed while doping silica with fluorine using gaseous compounds, and it provides for uniform distribution of fluorine within the dense grains of silica. Thus, the method makes it possible to obtain smaller variation in index within an optical fiber preform than is the case when using the prior art method of fluorination in a crucible. | The invention relates to a method of doping silica with fluorine. The method described comprises mixing a powder of silica granules with a solid fluorine compound, thermally decomposing the solid fluorine compound under an inert atmosphere, and densifying the granules to obtain dense grains of doped silica. It is preferable to use ammonium bifluoride. The invention is applicable to preparing high index silica glass, in particular for fabricating optical fiber preforms. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a safety needle with a telescoping shield that is triggered during a standard sequence of operation of a medical procedure and, more particularly, relates to a needle and hub assembly having a telescoping shield that is triggered when an evacuated tube is mounted in the evacuated tube needle holder.
2. Background Description
An evacuated collection tube, needle and needle holder are commonly used by a doctor, phlebotomist or nurse to draw a sample of body fluid from a patient in a hospital or doctor's office for diagnostic testing. During the use of such a needle holder, the distal end of the needle in the needle holder is inserted in a vein of the patient. The evacuated collection tube is then inserted into the proximal end of the needle holder until a needle within the holder pierces a closure on the end of the tube. The vacuum in the tube then draws a body fluid sample from the patient through the needle and into the tube. After the collection process is complete the needle is removed from the vein and disposed of.
Because of the great concern that users of such needles may be contaminated with the blood of a patient by accidental sticks from the contaminated needle, it is preferable to cover the contaminated needle as soon as it is removed from the vein. For this reason, many developments have been made to provide means for covering the contaminated needle, once it is removed from the patient. These devices usually involve some sort of shield arrangement that moves in place over the contaminated needle once it has been removed from the patient. However, these shield arrangements have required the use of one or two hands to perform the operation of moving the shield over the contaminated needle, which is a hindrance to the user.
Alternatively, needles with internal or external blunting cannulas have been used that extend from the needle to blunt the distal end. However, these devices require an additional manual operation to drive the blunting cannula over or out of the needle upon completion of blood drawing to protect the user from the sharp end of the needle and also allow the user to draw blood without triggering the safety device. Such devices also require the internal diameter of the needle to be decreased which may affect blood flow or require the external diameter of the needle to be enlarged which may cause unnecessary discomfort to the patient.
Other needles have shields that are activated during the venipuncture operation when the shield comes in contact with the skin. Using the skin to activate the device is not desirable since the device may not activate if the needle does not penetrate sufficiently or may cause the shield to inadvertently lock when probing for the vein. Such devices may also require excessive penetration into some patients to cause the triggering means to activate the device which will cause a phlebotomist to unnecessarily have to change their standard method or procedure.
SUMMARY OF THE INVENTION
The present invention overcomes the problems identified in the background material by providing a safety needle incorporating a shield that extends over the distal end of the needle when released by an actuator that is triggered during a standard sequence of operation of a medical procedure.
For example, the safety needle incorporates a telescoping shield that extends by means of a compression spring from a starting retracted position to a venipuncture partially extended position during the standard sequence of operation of drawing a blood sample with an evacuated blood collection tube and needle holder. In particular, when the closure or stopper on the collection tube compresses a rubber multiple sample sleeve on the proximal end of the needle, an actuator is triggered by the closure and/or sleeve to cause the telescoping shield to extend. Then, when the needle is removed from the patient the shield continues to extend to a fully extended and locked position over the distal end of the needle rendering the needle safe and preventing needle stick injuries.
The needle assembly of the present invention consists of a double ended needle cannula having a distal end for venipuncture and a proximal end for puncture of the closure on the evacuated blood collection tube. The needle is retained within a needle hub that attaches to the needle holder and includes the compression spring, an actuator and a telescoping shield. The elastomeric or rubber multiple sample sleeve encompasses the proximal end of the needle cannula. Upon insertion of the evacuated blood collection tube into the needle holder the closure and/or sleeve drives the actuator linearly in the distal direction through a slot in the needle hub. An arm on the distal end of the actuator includes a cam face that engages with a mating surface on a lug at the proximal end of the telescoping shield. The surfaces interact to rotate the shield out of the starting retracted position into a channel whereby the shield is pushed by the compression spring down the length of the cannula to a venipuncture partially extended position. The rotation also loads a torsion spring on the shield to maintain the shield in a loaded/torqued position when at the venipuncture partially extended position. When venipuncture is complete and the needle is withdrawn from the patient, the shield is further extended by the compression spring to the fully extended position. In that position the shield rotates due to the torsion spring to move the lug on the shield from the channel over a ramp and into a distal locking pocket on the needle hub. When the lug is in the locking pocket the shield sufficiently covers the distal end of the needle cannula and renders the needle assembly safe.
An object of the present invention is to provide a needle shield that is automatically activated without having to use one or two hands to perform the shielding operation or an additional action not associated with the normal procedure used during blood collection.
Of course, the present invention is not limited to activation by a blood collection tube since it would be equally functional on a syringe with activation by syringe plunger or on a catheter with activation when the introducer needle is retracted and removed from the catheter device.
These and other aspects, features and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a needle assembly according to the present invention in a starting retracted position;
FIG. 2 is a perspective view of the needle assembly shown in FIG. 1 mounted on a needle holder;
FIG. 3 is a partial cross-sectional view of the needle and holder assembly shown in FIG. 2 in the starting retracted position;
FIG. 4 is a partial cross-sectional view of the needle and holder assembly shown in FIG. 2 in a venipuncture partially extended position;
FIG. 5 is a partial cross-sectional view of the needle and holder assembly shown in FIG. 2 in a fully extended and locked position;
FIG. 6 is a partial perspective view of the needle hub;
FIG. 7 is a cross-sectional view of the needle assembly shown in FIG. 3 along lines 7--7;
FIG. 8 is a cross-sectional view of the needle assembly shown in FIG. 4 along lines 8--8; and
FIG. 9 is a cross-sectional view of the needle assembly shown in FIG. 5 along lines 9--9.
DETAILED DESCRIPTION
FIG. 1 is a perspective view of a needle assembly 1 according to the present invention in a starting retracted position. Assembly 1 includes a needle cannula 2 mounted in a needle hub 5 having a telescoping shield 3 mounted thereon for movement from a starting retracted position (FIGS. 3 and 7) through a venipuncture partially extended position (FIGS. 4 and 8) to a fully extended and locked position (FIGS. 5 and 9) covering a distal end 6 of needle cannula 2. A proximal end 7 of needle cannula 2 is encompassed by an elastomeric or rubber multiple sample sleeve 8 that is attached to a distal end of needle hub 5 to seal proximal end 7 and prevent fluid from flowing through cannula 2.
Assembly 1 also includes an actuator 4 having a sleeve 14 and a pair of arms 15 that are used to trigger telescoping shield 3 for transport from its starting retracted position to its final fully extended and locked position. As shown in FIG. 1 and described further below, telescoping shield 3 includes a torsion spring 13 having a tab 12 that travels in a longitudinal track 53 on needle hub 5. Shield 3 also includes a pair of lugs 11 that travel in longitudinal channels 54 on needle hub 5 and interact with arms 15 on actuator 4 to trigger movement of telescoping shield 3, when actuator 4 is pushed in the distal direction.
FIG. 2 is a perspective view of needle assembly 1 mounted in needle holder 20. Needle holder 20 includes a proximal end 21 and a distal end 23 wherein proximal end 21 includes an opening 22 for receiving an evacuated blood collection tube 50 (FIG. 4) having a closure 51. As more clearly shown in FIG. 3, needle hub 5 on needle assembly 1 includes a flange 9 and a plurality of threads 17 that mate with a plurality of threads 18 in distal end 23 of needle holder 20 to fasten or otherwise attach needle assembly 1 to needle holder 20.
FIG. 3 is a partial cross-sectional view of needle assembly 1 and needle holder 20 with needle assembly 1 in the starting retracted position. In the starting retracted position, cannula 2 extends from a distal end 35 of needle shield 3 so that distal end 6 of cannula 2 is ready for insertion through a patient's skin and into a vein. In the starting retracted position, since no blood collection tube 50 and closure 51 have been inserted into needle holder 20, actuator 4 has not been pushed or moved in the distal direction and shield 3 has not been triggered or activated.
As more clearly shown in FIG. 3, each of arms 15 extending in the distal direction from sleeve 14 on actuator 4 include cam faces 10 that are aligned with and/or adjacent to corresponding mating surfaces 16 are the proximal ends of lugs 11 on shield 3. Cam face 10 and mating surface 16 are arranged to interact with each other to trigger movement of telescoping shield 3 out of the starting retracted position when actuator 4 is pushed in the distal direction. In particular, as actuator 4 is pushed in the distal direction, cam face 10 mates with mating surface 16 to cause lug 11 and shield 3 to rotate in the direction of arrow A in FIG. 7, which allows shield 3 to begin movement down needle hub 5 in the distal direction. The force needed to move or transport shield 3 down needle hub 5 in the distal direction to the venipuncture partially extended position shown in FIG. 4, described below, is provided by a compression spring 19 mounted within needle hub 5.
FIG. 4 shows needle assembly 1 in the venipuncture partially extended position where distal end 6 of needle cannula 2 has punctured a patient's skin 30 and needle assembly 1 has been triggered by movement of actuator 4 in the distal direction. Needle assembly 1 is triggered by the insertion of an evacuated blood collection tube 50 having a closure 51 into needle holder 20, when a top surface 52 of closure 51 compresses multiple sample sleeve 8 after it has been penetrated by proximal end 7 of needle cannula 2. When multiple sample sleeve 8 is compressed by closure 51, sleeve 8 and/or closure 51 interact with and push sleeve 14 of actuator 4 in the distal direction to cause cam surface 10 on arm 15 to mate with mating surface 16 on lug 11 of shield 3. When these surfaces interact, shield 3 is rotated in the direction of arrow A (FIG. 7) and lug 11 is pushed out of a proximal pocket 56 (FIG. 6) in needle hub 5 and into a channel 54 (FIG. 6) in needle hub 5.
After lug 11 has moved into channel 54 compression spring 19 (FIG. 5) transports shield 3 in the distal direction until distal end 35 of shield 3 makes contact with the patient's skin surface 30, as shown in FIG. 4. The phlebotomist can then continue to draw body fluid samples into one or more evacuated collection tubes 50 by easily removing and replacing evacuated tubes 50 until sufficient body fluid has been drawn. The present invention, therefore, permits the user to perform the medical procedure without changing their normal sequence of operation, since no conscious action is needed to activate or otherwise control telescoping shield 3. It should be understood that telescoping shield 3 is triggered and transported to the partially extended position merely by pushing closure 51 onto proximal end 7 of cannula 2 and/or compressing multiple needle sleeve 8. After actuator 4, has triggered and transported telescoping shield 3 from the retracted position shown in FIG. 3 to the partially extended position shown in FIG. 4, needle assembly 1 is ready to transport telescoping shield to the fully extended position shown in FIG. 5 when cannula 2 is removed from the patient's skin 30.
FIG. 5 is a partial cross-sectional view of needle assembly 1 and needle holder 20 showing needle assembly 1 in the fully extended and locked position. In this position shield 3 is fully extended such that distal end 35 of shield 3 extends beyond distal tip 6 of cannula 2. FIG. 5 also shows a proximal seat 33 in needle hub 5 and a distal seat 34 in shield 3 for each respective end of compression spring 19 and shows compression spring 19 in its fully extended state where it has fully transported shield 3 from the starting retracted position (FIG. 3) through the venipuncture partially extended position (FIG. 4) and finally to the fully extended and locked position (FIG. 5). FIG. 5 also shows lug 11 located in distal pocket 55 (FIGS. 6 and 9) which together provide means for locking shield 3 in the fully extended position.
FIG. 6 is a partial perspective view of needle hub 5 having a distal end 61 and a proximal end 62. FIG. 6 provides a better view of longitudinal channel 54 and proximal pocket 56 at proximal end 62 and distal pocket 55 at distal end 61. In addition, FIG. 6 shows longitudinal track 53 which is arranged to receive and guide tab 12 on torsion spring 13 as shield 3 moves from the starling retracted position (FIG. 3) through the venipuncture partially extended position (FIG. 4) and finally to the fully extended and locked position (FIG. 5), where torsion spring 13 causes shield 3 to rotate in the direction of arrow B (FIG. 9) and move lugs 11 into their respective distal pockets 55 on needle hub 5.
FIG. 7 is a cross-sectional view of needle assembly 1 shown in FIG. 3 at its starting retracted position along lines 7--7. As shown in FIG. 7, tab 12 of torsion spring 13 is located in torsion spring track 53 in needle hub 5 and each shield lug 11 is located in a respective proximal pocket 56. Each of these lugs 11 are held in each pocket 56 by a respective retention rib 57. When closure 51 is penetrated by proximal end 7 of cannula 2 and sleeve 14 on actuator 4 causes distal lateral movement of actuator 4 and mating of surfaces 10 and 16, shield 3 is rotated in the direction of arrow A and lugs 11 move over retention ribs 57 into their respective channels 54. Once lugs 11 are in their respective channel 54, compression spring 19 causes distal movement of shield 3 until it reaches the partially extended position shown in FIG. 4. FIG. 8 is a cross-sectional view of needle assembly 1 shown in FIG. 4 along lines 8--8, that more clearly shows lugs 11 in channels 54 and tab 12 of torsion spring 13 in track 53. FIG. 8 also more clearly shows torsion spring 13 under torque due to the rotation of shield 3 in the direction of arrow A.
After venipuncture and withdrawal of cannula 2 from the patient's skin 30, shield 3 moves to its fully extended and locked position shown in FIG. 5. As more clearly shown in FIG. 9, a cross-sectional view of needle assembly 1 shown in FIG. 5 along lines 9--9, each lug 11 is located and locked in a respective distal pocket 55 by a locking ramp 58. In particular, lugs 11 have moved from channels 54 over locking ramps 58 and into distal pockets 55 by rotation of shield 3 in the direction of Arrow B because of the torque on torsion spring 13. FIG. 9 also shows tab 12 on torsion spring 13 located in track 53, but no longer under torque.
Alternatively, rotation of shield 3 would not be needed when distal pocket 55 and proximal pocket 56 are axial with longitudinal channels 54. In such a structure arm 15 on actuator 4 would lift lug 11 out of proximal pocket 56 to trigger movement of shield 3 out of the retracted position. After venipuncture lug 11 would move axially down channel 54 and into distal locking pocket 55 to lock shield 3 in the fully extended position. Torsion spring 13 would not be needed since no rotation is necessary. Of course, other variations could be used and still fall within the scope of the present invention, such as, combining an axial pocket with a pocket requiring rotation.
The above described needle assembly 1 with its telescoping shield 3 is used by a phlebotomist in the following manner and method. After a user has removed needle assembly 1 from its sterile package, it is snap mounted or screw mounted onto distal end 23 of needle holder 20 using threads 17 and 18 until flange 9 comes into contact with distal end 23 of needle holder 20. The user then prepares a venipuncture site on the patient's skin 30 and applies a tourniquet prior to venipuncture.
Venipuncture is then performed by inserting distal end 6 of needle cannula 2 into patient's skin 30 and into a vein. When distal end 6 has been properly inserted and evacuated blood collection tube 50 with its closure 51 is inserted into open end 22 of needle holder 20, closure 51 is then punctured by proximal end 7 of needle cannula 2. When puncture of closure 51 has occurred sufficiently to contact and move actuator 4 in a distal direction, cam face 10 on arm 15 of actuator 4 meets with mating surface 16 on lug 11 of shield 3 to cause shield 3 to rotate in direction A and activate transportation of shield 3 in the distal direction toward the venipuncture site and into the partially extended position.
In addition to activating telescoping shield 3, when proximal end 7 enters into evacuated tube 50 body fluid flows through cannula 2 into evacuated tube 50 and when sufficient body fluid has been received the user can remove evacuated tube 50 from tube holder 20 and continue drawing body fluid with additional evacuated blood collection tubes 50. When evacuated blood collection tube 50 is removed from needle holder 20 multiple sample sleeve 8 returns to its original position to close and seal distal end 7 of cannula 2 and stop the flow of body fluid through cannula 2. When no more body fluid is desired to be collected, needle cannula 2 is withdrawn from the patient's vein and skin 30 permitting shield 3 to further extend to the fully extended and locked position shown in FIG. 5, where distal end 35 of shield 3 extends beyond and sufficiently shields distal end 6 of needle cannula 2.
In the foregoing discussion, it is to be understood that the above-described embodiments of the present invention are merely exemplary. For example, the distal locking pocket can alternatively be located linearly in the channel at the distal end of the needle hub to alleviate the need for rotation by the torsion spring. In addition, of course, the present invention is not limited to activation by a blood collection tube since it would be equally functional on a syringe with activation by syringe plunger rod or on a catheter with activation when the introducer needle is retracted and removed from the catheter device. Other suitable variations, modifications and combinations of the above described features could be made to or used in these embodiments and still remain within the scope of the present invention. | A needle assembly having a telescoping shield that extends over the distal end of the needle when released by an actuator that is triggered during a standard sequence of operation of a medical procedure. For example, the telescoping shield extends by a compression spring from a starting retracted position to a venipuncture partially extended position during the standard sequence of operation of drawing a blood sample with an evacuated blood collection tube and needle holder. After the procedure is complete and the needle is removed from the patient the shield continues to extend to a fully extended and locked position over the distal end of the needle rendering the needle safe and preventing needle stick injuries. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
Not applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
BACKGROUND OF THE INVENTION
Embodiments of the invention relate to riserless mud return systems used in the oil production industry. More particularly, embodiments of the invention relate to a novel system and method for riserless mud return using a subsea pump suspended along a rigid mud return line.
Top hole drilling is generally the initial phase of the construction of a subsea well and involves drilling in shallow formations prior to the installation of a subsea blowout preventer. During conventional top hole drilling, a drilling fluid, such as drilling mud or seawater, is pumped from a drilling rig down the borehole to lubricate and cool the drill bit as well as to provide a vehicle for removal of drill cuttings from the borehole. After emerging from the drill bit, the drilling fluid flows up the borehole through the annulus formed by the drill string and the borehole. Because, conventional top hole drilling is normally performed without a subsea riser, the drilling fluid is ejected from the borehole onto the sea floor.
When drilling mud, or some other commercial fluid, is used for top hole drilling, the release of drilling mud in this manner is undesirable for a number of reasons, namely cost and environmental impact. Depending on the size of the project and the depth of the top hole, drilling mud losses during the top hole phase of drilling can be significant. In many regions of the world, there are strict rules governing, even prohibiting, discharges of certain types of drilling fluid. Moreover, even where permitted, such discharges can be harmful to the maritime environment and create considerable visibility problems for remote operated vehicles (ROVs) used to monitor and perform various underwater operations at the well sites.
For these reasons, systems for recycling drilling fluid have been developed. Typical examples of these systems are found in U.S. Pat. No. 6,745,851 and W.O. Patent Application No. 2005/049958, both of which are incorporated herein by reference in their entireties for all purposes. Both disclose systems for recycling drilling fluid, wherein a suction module, or equivalent device, is positioned above the wellhead to convey drilling fluid from the borehole through a pipeline to a pump positioned on the sea floor. The pump, in turn, conveys the drilling fluid through a flexible return line to the drilling rig above for recycling and reuse. The return line is anchored at one end by the pump, while the other end of the return line is connected to equipment located on the drilling rig.
Positioning the pump on the sea floor requires that the pump be designed and manufactured to withstand hydrostatic forces commensurate with the depth of the sea floor. Also, positioning the pump on the sea floor may be undesirable in certain conditions due to the time needed to retrieve the pump in the event that the pump needs maintenance or bad weather occurs
Thus, embodiments of the invention are directed to riserless mud return systems that seek to overcome these and other limitations of the prior art.
SUMMARY OF THE PREFERRED EMBODIMENTS
Systems and methods for drilling a well bore in a subsea formation from an offshore structure positioned at a water surface and having a drill string that is suspended from the structure and including a bottom hole assembly adapted to form a top hole portion of the well bore. A drilling fluid source on the offshore structure supplies fluid through the drill string to the bottom hole assembly where the fluid exits from the bottom hole assembly during drilling and returns up the well bore. A suction module is disposed at the sea floor and collects the fluid emerging from the well bore. A pump module is disposed on a return line, which is in fluid communication with the suction module, at a position below the water surface and above the sea floor. The pump module is operable to receive fluid from the suction module and pump the fluid through the return pipe to the same or a different offshore structure,
Thus, embodiments of the invention comprise a combination of features and advantages that enable substantial enhancement of riserless mud return systems. These and various other characteristics and advantages of the invention will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which:
FIG. 1 is a schematic representation of a drilling rig with a riserless mud return system comprising a subsea pump suspended along a rigid mud return line in accordance with embodiments of the invention;
FIGS. 2A and 2B are schematic representations of the docking joint depicted in FIG. 1 ; and
FIG. 3 is a schematic representation of the subsea pump module depicted in FIG. 1 ,
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Various embodiments of the invention will now be described with reference to the accompanying drawings, wherein like reference numerals are used for like parts throughout the several views. The drawing figures are not necessarily to scale. Certain features of the invention may be shown exaggerated in scale or in somewhat schematic form, and some details of conventional elements may not be shown in the interest of clarity and conciseness.
Preferred embodiments of the invention relate to riserless mud return systems used in the recycling of drilling fluid. The invention is susceptible to embodiments of different forms. There are shown in the drawings, and herein will be described in detail, specific embodiments of the invention with the understanding that the disclosure is to be considered an exemplification of the principles of the invention and is not intended to limit the invention to that illustrated and described herein. It is to be fully recognized that the different teachings of the embodiments discussed below may be employed separately or in any suitable combination to produce desired results.
Referring now to FIG. 1 , drilling rig, 5 includes drill floor 10 and moonpool 15 . An example of an offshore structure, drilling rig 5 is illustrated as a semi-submersible floating platform, but it is understood that other platforms or structures may also be used. For example, offshore structures include, but are not limited to, all types of rigs, barges, ships, spars, semi-submersibles, towers, and/or any fixed or floating platforms, structures, vessels, or the like,
Suction module 20 is positioned on the sea floor 25 above borehole 30 . Drill string 35 is suspended from drill floor 10 through suction module 20 into borehole 30 . Deployment and hang-off system 40 is disposed adjacent to moonpool 15 and supports the return string 45 , which is secured to the sea floor 25 by anchor 50 . Although this exemplary embodiment depicts return string 45 coupled to drilling rig 5 , it is understood that, in other embodiments, return string 45 may be coupled to and supported by the same or another offshore structure and can return fluid to the same offshore structure as coupled to the drill string 35 or to a second offshore structure. Return string 45 further includes upper mud return line 55 , pump module 60 , docking joint 65 , lower mud return line 70 , and emergency disconnect 75 .
Upper and lower mud return lines 55 , 70 are both formed from pipe, such as drill pipe or other suitable tubulars known in the industry. Mud return lines 55 , 70 are preferably formed from a series of individual lengths of pipe connected in series to form the continuous line. In preferred embodiments, mud return lines 55 , 70 are rigid, having only inherent flexibility due to their long, slender shapes. As it is used herein, the term “rigid” is used to describe the mud return lines as being constructed from a material having significantly greater rigidity than the coiled tubing or flexible hose conventionally used in mud return lines. In other embodiments, mud return lines 55 , 70 may be non-rigid or flexible, for example coiled tubing, flexible hose, or other similar structures.
Upper mud return line 55 is connected at its upper end to deployment and hang-off system 40 and at its lower end to docking joint 65 , which is located below sea level 80 . Pump module 60 is releasably connected to docking joint 65 . Lower mud return line 70 runs from docking joint 65 and is secured to the sea floor by anchor 50 . In certain embodiments, emergency disconnect 75 may releasably couple lower mud return line 70 to anchor 50 . Suction hose assembly 85 extends from suction module 20 to lower mud return line 70 so as to provide fluid communication from the suction module to the mud return line.
Prior to initiating drilling operations, return string 45 is installed through moonpool 15 . Installation of return string 45 includes coupling anchor 50 and emergency disconnect 75 (if desired) to lower mud return line 70 . Anchor 50 is lowered to sea floor 25 by adding individual joints of pipe that extend the length of lower mud return line 70 . As return string 45 is installed, docking joint 65 and upper mud return line 55 are added. Pump module 60 may be run with return string 45 or after the string has been completely installed. Upon reaching the sea floor 25 , anchor 50 is installed to secure return string 45 to the sea floor 25 . Return string 45 is then suspended from deployment and hang-off system 40 and drilling operations may commence.
During drilling operations, drilling fluid is delivered down drill string 35 to a drill bit positioned at the end of drill string 35 . After emerging from the drill bit, the drilling fluid flows up borehole 30 through the annulus formed by drill string 35 and borehole 30 . At the top of borehole 30 , suction module 20 collects the drilling fluid. Pump module 60 draws the mud through suction hose assembly 85 , lower mud return line 70 , and docking joint 65 and then pushes the mud upward through upper mud return line 55 to drilling rig 5 for recycling and reuse. During operation, anchor 50 limits movement of return string 45 in order to prevent the return string from impacting other submerged equipment.
FIGS. 2A and 2B are schematic representations of one embodiment of a docking joint 65 as depicted in FIG. 1 . As shown in FIG. 2A , docking joint 65 includes housing 100 , inlet line 105 , outlet line 110 , isolation valves 115 , 120 , and upper connecting pipe 122 . Housing 100 includes fluid outlet port 125 at its upper end 128 and a fluid inlet port 130 at its lower end 132 . Housing 100 includes a first internal passage that provides fluid communication between fluid inlet port 130 and inlet line 105 and a second internal passage that provides fluid communication between outlet line 110 and fluid outlet port 125 . Housing 100 may be formed from a single block of material or may be constructed from separate pieces as a fabricated assembly.
Inlet line 105 further includes inlet 140 that is coupled to housing 100 , outlet 145 that connects to pump module 60 , and flowbore 150 providing fluid communication therebetween. Similarly, outlet line 110 further includes inlet 155 that connects to pump module 60 , outlet 160 coupled to housing 100 , and a flowbore 165 providing fluid communication therebetween. Isolation valves 115 , 120 are positioned along flowbore 150 , 165 , respectively, in order to selectively allow fluid communication along inlet line 105 and outlet line 110 .
Mud return line 70 is coupled to housing 100 at lower end 132 via a threaded connection or other suitable type of connection. Upper connecting pipe 122 couples mud return line 55 to housing 100 at upper end 128 via threaded connections or other suitable type of connections known in the industry. Referring now to FIG. 2B , connecting pipe 122 further includes helix 138 , which is configured to align pump module 60 with docking joint 65 . Cover 170 provides a surface 180 on which pump module 60 is seated when pump module 60 is installed. Cover 170 further includes cut-outs 175 , which permit pump module 60 , when installed, access to isolation valves 115 , 120 , inlet line 105 and outlet line 110 .
FIG. 3 illustrates one embodiment of a subsea pump module 60 that is operable to interface with docking joint 65 , as shown in FIGS. 2A and 2B . Pump module 60 includes pump assemblies 200 , flowlines 205 , and isolation valves 210 , all assembled and contained within frame 215 . Pump assemblies 200 are arranged in series so that flowlines 205 provide fluid communication through pump module 60 that allows fluid from return line 70 to be successively pressurized by each pump assembly 200 . Valves 210 allow for the flow to be directed to the pump assemblies 200 as desired for a particular application. Pump assemblies 200 are illustrated as disc or, alternatively, centrifugal pump units but it is understood that any type of pump can be used in pump module 60 . Power for pump-motor assemblies 200 may be provided by electrical wiring from drilling rig 5 . In some embodiments, isolation valves 210 may be electrically actuated also via electrical wiring from drilling rig 5 . Additionally, isolation valves 210 may be manually actuated during operations involving ROVs.
Frame 215 protects pump assemblies 200 and their piping components and provides attachment points for lifting pump module 60 and facilitating the installation and retrieval of the module. Frame 215 includes an opening 220 , which permits pump module 60 to be inserted over mud return line 55 (see FIGS. 1 and 2A ) and lowered along mud return line 55 to docking joint 65 during installation. Frame 215 is also configured to interface with helix 138 so as to align pump module 60 with docking joint 65 during installation of the pump module.
As described above in reference to FIG. 1 , docking joint 65 is installed with mud return lines 70 , 55 to form return string 45 . Prior to the installation of pump module 60 , isolation valves 115 , 120 on lines 105 , 110 of docking joint 65 may be closed to prevent circulation of seawater into return string 45 . Pump module 60 may then be installed along return string 45 with docking joint 65 or independently of docking joint 65 .
During normal deployment procedures, pump module 60 may be installed with docking joint 65 . In this scenario, pump module 60 is coupled to docking joint 65 and the two components are then lowered to the desired depth. To enable these procedures, docking joint 65 is designed to allow pick-up of pump module 60 without breaking return string 45 . Installation of pump module 60 with docking joint 65 in this manner is less time consuming than conventional methods because it is not necessary to break return string 45 . Retrieval of pump module 60 using docking joint 65 is also more efficient for this same reason.
Alternatively, during maintenance and/or emergency procedures, pump module 60 may be installed independently of docking joint 65 . For example, when pump module 60 requires maintenance and/or bad weather approaches, it may be necessary to retrieve pump module 60 while return string 45 , including docking joint 65 , remains in place. After maintenance of pump module 60 is completed or the bad weather has passed, pump module 60 may be lowered along return line 55 to engage docking joint 65 .
In either scenario, installation of pump module 60 preferably includes inserting mud return line 55 into opening 220 and lowering pump module 60 over the mud return line 55 to docking joint 65 . As pump module 60 is lowered over connecting line 122 of docking joint 65 , pump module 60 engages helix 138 , causing pump module 60 to rotate as pump module 60 descends toward docking joint 65 such that when pump module is seated on docking joint 65 , pump module 60 is aligned with cover 170 and engaged with inlet line 105 and outlet line 110 . Aligning pump module 60 with cover 170 allows pump module 60 access, via cut-outs 175 , to isolation valves 115 , 120 .
In some embodiments, seating pump module 60 on docking joint 65 automatically actuates isolation valves 115 , 120 from closed positions to open positions. Conversely, unseating pump module 60 from cover 170 of docking joint 65 actuates isolation valves 115 , 120 to closed positions. In other embodiments, seating and unseating of pump module 60 in this manner may not actuate isolation valves 115 , 120 . Rather, a signal transmitted to the isolation valves 115 , 120 from a remote location, erg drilling rig 5 , actuates isolation valves 115 , 120 . Additionally, isolation valves 115 , 120 may be manually actuated during operations involving ROVS.
After pump module 60 is installed and isolation valves 115 , 120 are opened, a fluid flowpath is established through pump module 60 . Once pump module 60 is operational and top hole drilling operations begin, drilling fluid is permitted to flow from mud return line 70 into docking joint 65 through fluid inlet port 130 . The drilling fluid then passes through inlet line 105 , entering at inlet 140 and exiting at outlet 145 . Upon exiting inlet line 105 , the drilling fluid flows through pump module 60 to outlet line 110 at inlet 155 . After exiting bypass line 110 through outlet 160 , the drilling fluid then flows from docking joint 65 through fluid exit port 125 , upward through connecting line 122 , and into mud return line 55 .
As described above, top hole drilling operations may commence after pump module 60 is installed. While operational, pump assemblies 200 of pump module 60 draw drilling fluid from the suction module 20 through suction hose assembly 85 , mud return line 70 , and bypass line 110 of docking joint 65 . Pump-motor assemblies 200 preferably then push the mud through flowlines 205 , through bypass line 110 of docking joint 65 , and upward through return line 55 to drilling rig 5 for recycling and reuse. Isolation valves 210 are actuated, as needed, to direct the flow of the drilling fluid through flowlines 205 and back into docking joint 65 .
In the event that pump module 60 requires maintenance and/or bad weather occurs necessitating the retrieval of pump module 60 , drilling operations cease. The flow of drilling fluid through pump module 60 is discontinued, and isolation valves 115 , 120 are actuated to closed positions. Pump module 60 is then disengaged from docking joint 65 and returned to drill floor 10 of drilling rig 5 , either for maintenance or safe stowage. Closure of isolation valves 115 , 120 prevents drilling fluid from dispersing into the surrounding water after pump module 60 is disengaged from docking joint 65 .
Retrieval of pump module 60 in this manner is expedited for at least two reasons. First, pump module 60 may be disengaged from docking joint 65 without the need to break the return string 45 . Second, pump module 60 is suspended above the sea floor 25 , rather than seated on it. Once maintenance has been performed on pump module 60 and/or bad weather has passed, pump module 60 may be redeployed by lowering pump module 60 along return string 45 to docking joint 65 where, again, pump module 60 engages docking joint 65 , as described above. Subsequent redeployment of pump module 60 is also expedited for these same reasons.
The terms “couple,” “couples,” and “coupled” and the like include direct connection between two items and indirect connections between items.
While preferred embodiments have been shown and described, modifications thereof can be made by one skilled in the art without departing from the scope or teachings herein. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the systems are possible and are within the scope of the invention. For example, the relative dimensions of various parts, the materials from which the various parts are made, and other parameters can be varied. In particular, the subsea pump module may comprise fewer or more pump-motor assemblies as needed to convey drilling fluid from the suction module through the return string to the drilling rig. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. | Systems and methods for drilling a well bore in a subsea formation from an offshore structure positioned on a water surface with a drill string that is suspended from the structure and includes a bottom hole assembly adapted to form a top hole portion of the well bore. A drilling fluid source on the offshore structure supplies drilling fluid through the drill string to the bottom hole assembly where the drilling fluid exits from the bottom hole assembly during drilling and returns up the well bore. A suction module is disposed at the sea floor and collects the drilling fluid emerging from the well bore. A pump module is disposed on a return line, which is in fluid communication with the suction module, at a position below the water surface and above the sea floor. The pump module is operable to receive drilling fluid from the suction module and pump the drilling fluid through the return pipe to the same offshore structure or a different offshore structure. | 4 |
FIELD OF THE INVENTION
This invention relates to methods and apparatus used in the manufacturure of semiconductor wafers and, more particularly, to methods and apparatus for measuring the registration between overlying layers of a semiconductor wafer.
BACKGROUND OF THE INVENTION
The fabrication of complex semiconductor devices involves multiple processing steps which result in multiple patterned layers of different materials being applied to a substrate. The different layers overlie each other and must be accurately registered, or matched in position, to insure proper operation of the device. Displacement between corresponding features on different layers can degrade device performance or can cause the device to be totally inoperative. As used herein, "displacement" between layers of a semiconductor wafer refers to a displacement in the plane of the wafer. As semiconductor devices have become increasingly complex, the dimensions of the features have been correspondingly reduced. This reduction in feature dimensions has reduced acceptable tolerances on displacement between layers. When, for example, the minimum feature size is 2 micrometers, the registration error cannot exceed about 0.1 micrometer.
To assist in registration of overlying layers in semiconductor wafers, it has been common practice to include reqistration patterns or marks in each layer of the wafer. The patterns overlie each other and have a predetermined relationship when the layers are correctly registered. One commonly used registration pattern includes squares of different sizes on the layers to be registered. When the two layers are exactly registered, the squares are concentric. Any registration error produces a displacement of the squares relative to each other.
Since semiconductor wafers including multiple complex integrated circuits are expensive to fabricate, it is usually desirable to verify registration after the application of each layer to the wafer. If the displacement of the layers is outside tolerable limits, the defective layer can, in some cases, be removed and replaced with an accurately reqistered layer. In other cases, the wafer is scrapped, thereby saving the expense of further processing steps on defective wafers.
In the past, it has been common practice to verify registration manually. Experienced operators examine the regqistration of overlying patterns on each wafer. Such techniques are relatively slow and are subject to human error and contamination of the semiconductor wafers.
More recently, automated systems for measuring registration have been developed. In one highly successful registration measurement system, registration errors are measured optically. A video camera records an image of a set of registration patterns through a microscope. The image is processed to obtain a measurement of the registration error.
A measurement system unavoidably introduces certain errors into the measured values. The errors arise both in the optical and the electronic portions of the system and cannot be eliminated entirely. Typically, such errors are systematic, that is, the errors have the same magnitude and direction from measurement to measurement. In the past, it has been customary to calibrate such registration systems by comparing measurements with those obtained from another system, such as a scanning electron microscope, that is known to be accurate. Such calibration techniques are relatively complex and require additional expensive equipment.
It is a general object of the present invention to provide improved methods and apparatus for registration measurement.
It is another object of the present invention to provide methods and apparatus for measuring registration of patterns wherein the effect of systematic errors is eliminated.
It is a further object of the present invention to provide methods and apparatus for determining the systematic errors in a registration measurement system without requiring additional calibration equipment.
It is yet another object of the present invention to provide methods and apparatus for registration measurement which are easy to use.
It is still another object of the present invention to provide methods and apparatus for measuring registration between overlying layers of a semiconductor wafer with high accuracy.
SUMMARY OF THE INVENTION
According to the present invention, these and other objects and advantages are achieved in a method for measuring displacement between a first pattern and a second pattern on a workpiece. The method comprises the steps of positioning the workpiece relative to a measurement apparatus for measurement of the displacement alonq a prescribed measurement direction, making a first measurement of displacement between the first pattern and the second pattern, causing rotation of the workpiece and the measurement apparatus relative to each other by substantially 180° about an axis that is substantially parallel to the measurement direction, making a second measurement of displacement between the first pattern and the second pattern, and determining an actual displacement between the first pattern and the second pattern from the first measurement and the second measurement.
By determining actual displacement from two measurements with the workpiece rotated by 180° between measurements, systematic errors are completely eliminated from the measured values. The step of determining an actual displacement includes the steps of determining an x-axis component, X, of actual displacement according to the equation X=(X1-X2)/2where X1is the x-axis component of the first measurement and X2is the x-axis component of the second measurement, and determining a y-axis component, Y, of actual displacement according to the equation Y=(Y1-Y2)/2where Y1is the y-axis component of the first measurement and Y2is the y-axis component of the second measurement.
The method of the invention can further include the step of determining the systematic errors in the measurement apparatus from the first and second measurements. An x-axis component, A, of error is determined according to the equation A=(X1+X2)/2. A y-axis component, B, of error is determined according to the equation B=(Y1+Y2)/2. The measured error values can be used to correct subsequent measurements.
In a preferred embodiment, the method of the present invention is used for measuring displacement between layers of a semiconductor wafer. Each layer of the semiconductor wafer is provided with registration patterns. An optical system, including a microscope and a camera, records an image of the patterns. The image is analyzed to measure displacement between the registration patterns. A first measurement is taken, the semiconductor wafer is rotated by 180° and a second measurement is taken. The actual displacement between the layers and systematic errors are determined as described above.
According to another aspect of the invention, there is provided apparatus for measuring displacement between a first pattern and a second pattern on a workpiece. The apparatus comprises measurement means for making first and second measurements of displacement between the first pattern and the second pattern. The first and second measurements are each taken along a prescribed measurement direction. The apparatus further includes means for causing rotation of the workpiece and the measurement means relative to each other after the first measurement and before the second measurement, by substantially 180° about an axis that is substantially parallel to the measurement direction, and means responsive to the first measurement and the second measurement for calculating an actual displacement between the first pattern and the second pattern.
BRIEF DESCRIPTION OF DRAWINGS
For a better understanding of the present invention together with other and further objects, advantages and capabilities thereof, reference is made to the accompanying drawings which are incorporated herein by reference and in which:
FIG. 1 is an illustration of a registration measurement system suitable for incorporation of the present invention;
FIG. 2 is a simplified block diagram of the registration measurement system;
FIGS. 3A and 3B are top and cross-sectional views, respectively, of a typical set of registration patterns;
FIG. 3C illustrates an alternative set of registration patterns;
FIGS. 4A and 4B illustrate the measurement technique of the present invention; and
FIG. 5 is a flow diagram illustrating the measurement technique of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
An automated system for measuring registration between layers of a semiconductor wafer is illustrated in FIGS. 1 and 2. The major elements of the system, including a wafer handler, an optical system and a computer system, are mounted in a cabinet 10. A cassette wafer holder 12 containing wafers to be measured is mounted on the system. A wafer transport pick (not shown) removes a wafer 16 from the cassette 12 and places it on a prealigner 14. The prealigner 14 rotates the wafer to a predetermined orientation by sensing the wafer flat. The wafer transport pick then transfers the wafer 16 from the prealigner 14 to a measurement stage 18. A suitable wafer handler is a Model CKG1 or CKG3 available from FSI. The stage 18 is movable in three dimensions for positioning selected registration patterns relative to the optical system as described hereinafter.
The optical system includes a microscope 20 and a video camera 22 positioned above the wafer 16. The microscope 20 typically carries several objectives ranging in power from 2.5X to 200X magnification. The wafer 16 is positioned on the stage 18 in a horizontal orientation. The microscope 20 and the camera 22 have a vertical optical axis. The stage 18 is moved until the registration patterns to be measured are located directly under the microscope 20. The microscope turret rotates to the desired objective, and a focused image of the registration patterns is recorded by the camera 22. In an example of the optical system, the microscope 20 is a type Zeiss Axiotron, and the camera 22 is a Dage MT168series camera.
Electrical signals representative of the image are supplied to an image processor 28 and a computer 30. Coupled to the computer 30 are an image monitor 32 for display of the image recorded by the camera 22, a text screen 34 and a keyboard 36 which constitute an input terminal for entering operator commands and a disk drive 38 for storing system software and data. A suitable image processor 28 is available from Recognition Technology, Inc. A suitable computer 30 is a Wyse 386.
The computer 30 processes the siqnals from the camera 22 that represent the image of the registration patterns in order to measure displacement between layers of the semiconductor wafer 16. The wafer 16 includes registration patterns or marks specifically intended to assist in registration. The registration patterns are typically located at multiple sites on the wafer 16.
A commonly-used box-in-box registration pattern set is illustrated in FIGS. 3A and 3B. A top view is shown in FIG. 3A, and an enlarged, partial, cross-sectional view of wafer 16 is shown in FIG. 3B. The pattern set includes a square pattern 50 on a first layer 52 of wafer 16 and a square pattern 54 on a second layer 56. The square patterns 50 and 54 have different dimensions. Typically, the patterns 50 and 54 have dimensions on the order of 10-20 micrometers. When layers 52 and 56 are perfectly registered, square patterns 50 and 54 are concentric. When the layers 52 and 56 are not perfectly registered, the patterns 50 and 54 are displaced relative to each other in the plane of the wafer. By measuring the displacement of patterns 50 and 54, the registration between layers 52 and 56 can be quantified.
An alternative registration pattern is illustrated in FIG. 3C. Anqled lines 60 are located on a first layer of the semiconductor wafer, and angled lines 62 are located on a second layer. It will be understood that a variety of different registration patterns can be utilized to measure registration.
The measurement of displacement between patterns utilizes known signal processing techniques. The distance between patterns 50 and 54 in FIG. 3A is determined by an analysis of signals from camera 22. The lines of patterns 50 and 54 each produce a transition in a scan line signal from camera 22. The time interval between a transition corresponding to pattern 54 and a transition corresponding to pattern 50 is representative of the distance between the patterns. Signal processing techniques for analyzing the camera image to determine displacement between patterns are well known to those skilled in the art.
In performing registration measurements with a system of the type shown in FIGS. 1 and 2, certain unavoidable errors are introduced by the measuring system. Most of the errors are systematic errors which have the same maqnitude and direction from measurement to measurement. Such errors include, for example, errors due to camera response and image processor response, mechanical errors, optical errors and illumination errors.
In accordance with the present invention, systematic errors are completely eliminated from the measurements without utilizing a known accurate system for calibration or comparison. A first set of displacement measurements is obtained as described above. The displacement between patterns on different layers of the semiconductor device 16 is expressed as an x-axis component and a y-axis component in the plane of wafer 16. The first set of measurements yields measurement values X1, Y1.
After the first measurement, the wafer 16 is rotated by 180° relative to the measurement direction, or axis, which is perpendicular to the plane of measurement. Assuming that the wafer 16 is positioned on stage 18 in a horizontal orientation and that the camera 22 and microscope 20 have a vertical optical axis, the wafer 16 is rotated about a vertical axis parallel to or coincident with the optical axis. However, regardless of the configuration of the system, the wafer is rotated about an axis parallel to or coincident with the measurement axis (an axis perpendicular to the plane of measurement). Rotation of the wafer 16 can be accomplished by rotation of the stage 18. Also, the wafer 16 can be transferred to the prealigner 14, rotated by 180°, and returned to the stage 18. Manual rotation of the wafer 16 is also possible. While rotation of the wafer 16 is usually most practical, the relative rotation can be effected by the optical system so that the image seen by the camera 22 is effectively rotated by 180°.
After rotation of the wafer 16 by 180°, a second set of displacement measurements is obtained. The second set of measurements is made on the same patterns as the first set of measurements. Since the wafer has been reversed, the direction of the displacement between patterns is reversed. If no errors were involved in the measurement, the magnitude of the displacement between patterns would be the same for both measurements. However, since systematic errors in the measurement system do not change direction when the wafer is rotated, the first and second sets of measurements yield different magnitudes.
As demonstrated below, the two sets of measurements can be combined to yield the actual displacement between patterns and values of the systematic errors in the measurement system. Based upon the above discussion, it can be seen that:
X1=+X+A (1)
X2=-X+A (2)
where
X1=x-axis component of the first measurement
X2=x-axis component of the second measurement
X=x-axis component of the actual displacement between patterns
A=total systematic error in X measurement.
Solving equations (1) and (2) for X and A yields:
X=(X1-X2)/2 (3)
A=(X1+X2)/2 (4)
Similarly, for y-axis measurements:
Y1=+Y+B (5)
Y2=-Y+B (6)
where
Y1=y-axis component of first measurement,
Y2=y-axis component of second measurement,
Y=y-axis component of actual displacement between patterns,
B=systematic error in Y measurement.
Solving equations (5) and (6) for Y and B yields:
Y=(Y1-Y2)/2 (7)
B=(Y1+Y2)/2 (8)
The measurement technique of the present invention is illustrated with reference to FIGS. 4A and 4B. In FIG. 4A, a box-in-box registration pattern set includes a pattern 70 on one level of a semiconductor wafer and a pattern 72 on a second level of the semiconductor wafer. The patterns 70 and 72 are displaced to illustrate the present invention. The center of pattern 70 is shown at 70a, and the center of pattern 72 is shown at 72a. In a first measurement, an x-axis displacement, X1, and a y-axis displacement, Y1, are measured. Patterns 70 and 72 are shown in FIG. 4B after rotation of the wafer by 180°. It can be seen that the direction of displacement between patterns 70 and 72 is reversed. In a second measurement, an x-axis displacement, X2, and a y-axis displacement, Y2, are measured. Because of the rotation of the wafer, X1 and X2 have opposite polarities, and Y1 and Y2 have opposite polarities. By utilizing equations (3), (4), (7) and (8), the actual displacement values X, Y and the total systematic errors A, B are calculated.
The measurement technique of the present invention can be utilized in two principal ways. In one approach, two measurements are taken at each selected pattern site in order to produce actual displacement values at each site. When this approach is used, the first measurements are taken at each selected site on the wafer, the wafer is rotated by 180° and second measurements are then taken at each selected site. The two sets of measurements are used to calculate the actual values of displacement between patterns at each site.
In an alternative approach, the systematic errors are determined initially or periodically. The systematic error values are used to calibrate the system. The measured error values are used to offset, or correct, subsequent displacement measurements.
The measurement technique of the present invention is summarized in a flow diagram in FIG. 5. Initially, a wafer is positioned on stage 16, and the optical system is focused on a selected set of registration patterns in step 80. The displacement X1, Y1 between the selected set of registration patterns is measured in a first measurement step 82. Next, the wafer is rotated about a vertical axis by 180° in step 84. The displacement X2, Y2 between the selected set of patterns is measured in a second measurement step 86. The measured values of displacement are used to calculate actual displacements, X, Y in accordance with equations (3) and (7) in step 88. The systematic errors A, B are calculated in accordance with equations (4) and (8) in step 90.
Table 1 shows sample data taken at five sites on a sample semiconductor wafer with the wafer oriented at 0° and at 180°. Table 1 also shows the measurement errors and the actual displacements derived from the measurement data.
TABLE 1______________________________________Site 180 Measurement ActualNumber 0 Degree Degree Error Displacement______________________________________X 1 -0.71 1.37 0.33 -1.042 -0.52 1.18 0.33 -0.853 0.01 0.65 0.33 -0.324 0.23 0.43 0.33 -0.105 -0.15 0.81 0.33 -0.48 0.33 average errorY 1 0.63 -1.57 -0.47 1.102 -0.46 -0.48 -0.47 0.013 -0.13 -0.81 -0.47 0.344 0.45 -1.39 -0.47 0.925 0.22 -1.16 -0.47 0.69 0.47 average error______________________________________
The measurement technique of the present invention has been described in connection with measuring reqistration of overlying layers in semiconductor wafers. It will be understood that the technique of the present invention can be used to remove systematic errors in any measurement system where symmetry can be exploited by rotating the workpiece being measured through 180°. The measurement technique of the present invention is applicable to measurement systems other than optical systems including, for example, particle beam systems, scanning laser systems, x-ray systems and backscattering systems.
While there has been shown and described what is at present considered the referred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims. | Method and apparatus for measuring displacement between layers of a semiconductor wafer wherein systematic errors associated with the measurement system are eliminated. An optical system, including a microscope and a camera, records an image of registration patterns on different layers of the wafer. The image is analyzed to measure displacement between the registration patterns. A first measurement is taken, the wafer is rotated by 180° about the measurement axis, and a second measurement is taken. The actual displacement between layers of the semiconductor wafer is calculated from the first and second measurements. Since the measured displacements change sign when the wafer is rotated and the systematic errors remain constant, systematic errors drop out of the calculated values of actual displacement. System errors can also be calculated for subsequent correction of measured values. | 6 |
FIELD OF THE INVENTION
This invention relates to a system for controlling heating and air conditioning within a building.
BACKGROUND OF THE INVENTION
It is known to supply and control heating and ventilation from a centralized source. Buildings are often built with dampers and temperature sensors within air ducts. These dampers can be controlled from a centralized location. Examples of this technology may be found in U.S Pat. No. 4,585,163 (the '163 patent), U.S. Pat. No. 4,732,318 (the '318 patent), U.S. Pat No. 4,406,397 (the '397 patent), and U.S. Pat. No. 4,646,964 (the '964 patent). A common problem of the devices cited in these patents is the difficulty and expense involved in fitting an already constructed building with a heating and air conditioning system. This problem of retrofittability is solved with the present invention.
One of the reasons the devices cited in prior art are difficult to fit into existing buildings is that their dampers are located within the air ducts. Most of the these dampers are single blade devices. Single blade dampers need significant amounts of space (about equal to the width or height of a damper, depending on the pivot direction) to reach a fully opened state. The space requirement, therefore, dictates that these single blade dampers be positioned within the actual duct, rather than at the duct outlet or opening. This single blade design can be seen in the '318 patent, the '964 patent, the '397 patent, and the '163 patent.
U.S. Pat. No. 4,258,877 (the '877 patent), issued Mar. 31, 1981, to White, discloses an electric, motor driven damper, with thermostatic switch control, for opening and closing air ducts. The actuator also shows the damper position from outside the duct, by the use of an indicator arm on the damper pivot. Like those devices mentioned above, the White damper blade must be located within the actual air conditioning duct. This is because the damper blade is comprised of an L-shaped member having a relatively long leg and a relatively short, slightly curved leg. The relatively long leg is rotatably mounted to a shaft which is mounted perpendicular to the flow of air. Therefore, the relatively long leg of the damper blade would be parallel or at an angle to the sides of the air conditioning duct. This would prevent this damper blade from being used directly behind the duct opening. Since the damper must be located within the air conditioning duct, retrofitting is impractical.
U.S. Pat. No. 2,790,372, issued Mar. 30, 1963, to Cooper, discloses an electric, motor driven damper, controlled by a thermostat, to increase the flow of cool/heated air into the individual rooms. There is no provision for controlling the temperature of the incoming air or for controlling the overall system temperature. The damper in this patent only functions in conjunction with an air supply duct which extends horizontally above the ceiling of a room and has a duct opening on its lower side. This single blade damper requires significant amounts of room to swing open. Therefore, like those dampers discussed above, this damper would not be easily retrofittable and, additionally, would be limited to a specific type of duct.
There are many methods of regulating individual room air temperature. The invention disclosed in the '318 patent issued Mar. 22, 1988, to Osheroff, regulates individual room air temperature by increasing the velocity of the heated or cold air through the ducts. The invention disclosed in the '397 patent, issued Sep. 27, 1983, to Kamata, regulates air temperature in an individual room by using an air quantity control device in each branched duct of a central heating and air conditioning system. The air quantity delivered to each room is monitored by velocity sensors in each branch duct, and the command sent to the central blower unit for either increased or decreased air volume. The invention disclosed in the '163 patent, issued Apr. 29, 1986, to Cooley, regulates air temperature by monitoring air volume.
It also should be noted that most of the prior art systems have sensing devices which are located within the air ducts. This is true in the '318 patent, the '397 patent, the '163 patent, and the '964 patent. This requirement makes retrofitting difficult.
The '964 patent, issued Mar. 3, 1987, to Parker, addresses the opening and closing of a duct, and the air temperature in the duct. The room temperature is set by a thermostat in the individual room, and commands the duct to open and close, based on the difference between room temperature and air duct temperature, measured by a sensor in the duct. This system cannot control individual room temperature by commanding the heater/air conditioner to add cooler air or heat, and relies on the main thermostat, for the overall temperature condition.
Accordingly, a principal object of the present invention is to provide an improved heating and air conditioning system which is easily retrofittable to a single family dwelling with a single duct system.
BRIEF SUMMARY OF THE INVENTION
In accordance with the present invention, a heating and air conditioning system for a single family dwelling, preferably includes a heater and air conditioning furnace system, a series of output ducts extending from the furnace system to individual rooms or zones of the dwelling, controllable output register units (often called vent units) at each duct opening into a zone, thermostats for each individual zone, and a central controller for controlling the furnace system and the individual zone registers. The system preferably also includes a master controller for selecting temperature conditions for each zone and for sending signals to a central controller.
This heating and air conditioning system is designed to be easily retrofitted into existing homes. One reason for the ease of retrofitting the present invention is its unique register assemblies. Preferably, these register assemblies have specially designed exterior flames made of side and corner units which allow the register to fit almost any duct opening, and an inner register unit. The exterior frame compensates for uneven walls such that the inner register unit remains undistorted. These register assemblies replace existing system dampers which require installation within existing air ducts.
The inner register unit of the invention has fully sealing, interlocking inner vanes or blades which are attached to a blade bar that may be electronically controlled by a central controller. Each register unit may be provided with a small motor (or servo) which controls its open/close state. The servo unit may be hardwired to or controlled via radio signals by the central controller. A second set of snap-in, adjustable blades may be provided at the front of the inner unit for directing air as desired within the local room or zone.
Thermostat units, preferably in each room, would monitor the room temperature. They would preferably be able to communicate with the central controller over house AC wiring or via a radio type transmitter and receiver. They would also provide the user with a source for controlling for the individual room temperature.
Additionally, the system would preferably include a master controller which could include an alternate source of control for the individual zones, a centralized source of control for the zones combined, and a timing means of control. The master controller would preferably communicate with the central controller over existing house AC wiring or via radio signals.
In addition to controlling and communicating with the room thermostats, the master controller and the register assemblies, the central controller may control the actual heating and air conditioning furnace.
The preferred embodiments of the invention may also include the following additional features:
1. The register assemblies may be either manually controlled or servo controlled.
2. The servo controlled register assemblies may be hardwired to the central controller or controlled via a radio-type receiver.
3. The individual zone thermostat may be mounted in a standard electrical outlet, mounted in a specially designed junction box in the wall, or connected to a table stand.
4. The frame of the inner register unit (interior frame) may be mounted to the exterior frame of the register unit by way of a molded serrated pull tap or a steel spring clip.
A major advantage of the present invention is that this system is easily retrofitted into a currently existing building. This is due, in part, to its unique register units or vent covers which can be placed at the opening of the air duct rather than a damper which is fitted within the actual duct. The retrofitability is also due to the ability of the system to communicate over standard building AC wiring or via radio signals.
Another major advantage of the present invention is having the temperature of an individual zone measured within the actual zone. The present invention measures the temperature at the individual zone thermostat. This feature provides more accurate temperature control within the zone than those systems which measure the temperature from within the air duct.
Other objects, features and advantages of the present invention will become apparent from a consideration of the following detailed description, and from the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a building having individual control zones connected by air ducts, each zone having its own thermostat and register assembly, the building also having a master controller and a central controller;
FIG. 2 is a perspective partially exploded view of a servo controlled register assembly incorporating certain features of the present invention;
FIG. 3 is a front view of the register assembly;
FIG. 4 is a top view of a servo controlled register assembly;
FIG. 5 is a cross-sectional top view of the side of the register assembly taken along line 5--5 of FIG. 3;
FIG. 6 is a cross-sectional side view of the top of the register assembly taken along line 6--6 of FIG. 3;
FIG. 7 is an enlarged perspective view of the corner coupling unit of the exterior register frame taken along line 7--7 of FIG. 3;
FIG. 8 is a cross-sectional view taken along lines 8--8 if FIG. 7 including an extruded side unit;
FIG. 9 is a perspective partially cutaway view of a manually controlled register assembly;
FIG. 10 is perspective view of a self powered, radio frequency controlled unit for the register;
FIG. 11a is a front view of an individual zone thermostat;
FIG. 11b is a side view of an individual zone thermostat;
FIG. 11c is a side view of an individual zone thermostat with a table stand;
FIG. 11d is a view of an individual zone thermostat mounted in a junction box;
FIG. 12a is a master controller including details of the display screen and the control pad;
FIG. 12b is a front view of the master controller with a pivoted panel or door covering the control pad switches;
FIG. 12c is a side view of the master controller with the door shut;
FIG. 13a is a block circuit diagram of the room thermostat circuit;
FIG. 13b is a block circuit diagram of the power/communication circuit of a hardwired room thermostat circuit;
FIG. 13c is a block circuit diagram of a radio controlled room thermostat circuit;
FIG. 14 is a block circuit diagram of the servo unit at each self powered, radio frequency controlled register;
FIG. 15a is a block circuit diagram of a hardwired central controller;
FIG. 15b is a block circuit diagram for a radio controlled central controller;
FIG. 16 is a block diagram of the program implemented by the Read Only Memory (ROM) of the central controller;
FIG. 17a is a diagram of converted digital signals;
FIG. 17b represents high frequency signals to be transmitted over AC 120 volt house wiring;
FIG. 18 is a depiction of the sequences of control signals transmitted by the central controller, the master controller, and the thermostat units;
FIG. 19a is a block circuit diagram of the master controller circuit;
FIG. 19b is a block circuit diagram of the power/communication circuit of a hardwired master controller;
FIG. 19c is a block circuit diagram of a power/communication circuit of a radio controlled master controller;
FIG. 20a is a block diagram of the connection between each of the servo-registers and the central controller; and
FIG. 20b is a variable pulse width signal for servo motor control.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
I. General
Referring more particularly to the drawings, FIG. 1 is a depiction of a dwelling heating and air conditioning system 26 installed in a building 28. The building 28 in accordance with a preferred embodiment of the invention may be a dwelling 28; however, other types of buildings such as businesses or recreational facilities could employ the same system. The dwelling 28 may contain multiple individual rooms or zones 42. The zones 42 are preferably connected by a series of ducts 40 for supplying heating and air conditioning to the zones 42. In each zone 42 there may be one or more openings of the duct 40. During installation of the system 26, each opening is preferably covered by a register assembly (or vent assembly) 30. Additionally, each zone 42 preferably contains a thermostat 50 which may be connected to a central controller 60. The building 28 may also be equipped with a master controller 70 which may communicate with the central controller 60. The central controller 60 preferably controls the actual heating, air conditioning, and fan unit 44 of the dwelling heating and air conditioning system 26.
II. Register Assembly
A. Exterior Frame
Each zone 42 of a building 28 may contain a register assembly 30 which includes an exterior frame 32. FIG. 2 is a perspective view of a register assembly 30 controlled by a servo motor 80, and detailing the exterior, duct adapting, register frame (exterior frame) 32, and an inner register unit 33. The exterior register frame 32 (also shown in FIG. 3) serves to accommodate uneven wall openings; and it is preferably composed of corner members 36 and side members 38. The corner member 36 (as shown FIG. 7) may have a square central portion 46 with two legs 48 extending from the central unit 46 and at right angles to each other. The legs 48 are thinner than the central portion 46, of the corner members 36 and extend outwardly from it. The legs 48 may then be inserted into the L-shaped extruded side members 38 (as shown in both FIG. 7 and FIG. 8).
The exterior, duct-adapting, register frame 32 is uniquely suited to the retrofitting feature of the present invention. The corner members 36 may be made of a standard size. The side members 38 are preferably made by an extrusion process involving forcing heated plastic through a die. The extruded side unit 38 can be made in a continuous process, and then cut to fit any size duct opening. An alternative embodiment of the exterior frame 32, albeit less economical, would be to use a molded frame or molded side units. Extruding, however, is more economical than the expensive process of molding an entire frame or four side units. Additionally, if a molded frame or side unit was used, many sizes would be needed to fit the various sized duct openings used in residential and commercial buildings. The side members 38 may be cemented or otherwise bonded to the corner units 36 to form complete exterior frames 32.
Finally, as shown in FIG. 2, one or more fastening holes 35 can be included on the exterior register frame 32. These holes 35 can be used to secure the register assembly 30 to the wall or surface surrounding the duct opening, or to the outwardly flanged ends of the duct.
B. Inner Register Unit
The inner register unit 33 (as shown in FIG. 2) is preferably comprised in part of a frame (interior frame) 34, outer directional vanes or blades 180, and inner sealing vanes or blades 182. The outer blades 180 have been removed at the left in FIG. 2 to show the inner vanes 182. FIG. 2 shows one embodiment of the present invention including air directional blades (air deflectors) 180 in the foreground and the surface-engaging, interlocking, sealing blades 182 in the background (discussed below in connection with FIG. 5). FIG. 3 is a front view of the register unit 30. In this view the frame of the inner register unit (interior frame) 34 is positioned within the exterior, wall compensating and duct-adapting, register frame 32.
FIG. 5 and FIG. 6 further detail the interface between the exterior frame 32 and the interior frame 34. These frames are preferably sealed together by way of interior/exterior rubber compliant sealing strips 37 which may be bonded to the outer wall of the interior frame 34. The exterior frame 32 is sealed to a wall or other surface by way of a compliant rubber strip 39 which is bonded within a recess of the extruded side units 38 exterior frame 32 (as seen in FIG. 5 and 6). These seals are necessary to prevent passage of air through gaps between the register unit frames (34 and 32) and the exterior frame 32 and the surface to which the register unit is mounted.
As shown in FIG. 2, the interior frame 34 may be held securely within the exterior frame 32 by a molded serrated pull tab 31. An alternative embodiment could include a spring steel clip to position the interior frame 34 within the exterior frame 32. Other fastening devices and seals known in the art would allow the interior frame 34 to be secured and sealed within the exterior frame 32 and the register to control air flow even if the wall or structure that the exterior frame 32 rests against is not flat.
FIG. 4 shows a top view of a servo controlled register assembly 30. (The actual mechanics of the servo unit 80 will be discussed in more detail in connection with FIG. 10 and FIG. 14.) The servo unit 80 may be used to control the position of the servo lever 189. In the preferred embodiment of the invention the lever 189 has only two positions, open and closed, corresponding to the signals represented in FIG. 20b; however, other embodiments could include three or more positions or a continuous spectrum of positions.
The servo lever 189 is preferably pivotally attached to each end of a stiff wire or thin connecting rod 192. The other end of the stiff wire 192 may be pivotally attached to the blade bar extension 194 which preferably extends perpendicularly from the blade bar 190. An alternative embodiment of the invention could have the wire 192 attached directly to the blade bar 190. Another alternative embodiment of the invention could use a manual lever 188 (as detailed in FIG. 9). The manual lever 188 would preferably include a handle or knob 187 extending into the room. Further, the manual lever 188 would preferably be pivotally connected to the blade bar extension 194.
1. Inner Interlocking Vanes
The blade bar 190 preferably has pivotally attached to it an array of inner, interlocking vanes or blades 182 for selectively shutting off the air flow through the register assembly 30. The inner vanes 182 are preferably attached to the blade bar 190 on the outer edge by way of blade pivot extensions 185 (as shown in FIG. 4 and FIG. 6) which may extend perpendicularly from the upper edges of the blades 182. The blade pivot extensions 185 are pivotally attached to the blade bar 190 by the pivot screw 196.
FIG. 5 details a horizontal cross section of the frame of the inner register unit (interior frame)34 including the inner, interlocking vanes 182. These vanes 182 are preferably pivotally attached to the interior frame 34 by pivot means 183. In one embodiment of the invention the pivot means includes a small cylindrical pivot disk 183 which is attached to one end of an interlocking inner vane 182. The cylindrical pivot disk 183 would then fit into a receiving notch 205 of a receiver bar 204. A receiver bar cover strip 206 may be used to cover the receiving notches 205 with the cylindrical pivot disks 183 "snapped in" so that the disks 183 are held in place. Alternatively, the notches may be configured so that the pivot disks snap into the notches so that the receiver bar cover strip is not needed. Other pivot means 183 such as pivot screws and other known pivot arrangements may be employed.
The interlocking vanes 182 are preferably rectangular-shaped and may have dimensions, for example, of 41/2" high and 11/4" wide. The dimensions are preferably such that the blades extend past the opening 200 defined by the interior frame blade ridge 198. The interior frame blade ridge 198 preferably has affixed to it a rubber or foam blade compliant seal. 199. When the blades 182 are in the closed position, they rest against the blade complaint seal 199 so that no air can pass.
The horizontal cross sections of the interlocking vanes 182 preferably have an essentially rectangular with cut-out rectangular portions at opposite diagonal corners (184 and 186). This cross section may be achieved by specifically extruding or molding the individual inner vanes 182, by molding a rectangular unit and "cutting out" the corner sections, or by combining two flat sections. If two flat sections were combined, each section, for example, be 41/2" long, 7/8" wide, and approximately 1/16" thick. The flat sections would then be coupled in a offset fashion so that about 1/4" of the width of each section overlaps the other flat section.
At the edge of the inner vane 182 by the cylindrical pivot disk 183, the cut-out portion forms an "under-engaging" surface 186. At the other end of the vane 182, the cut-out portion forms an "over-engaging" surface 184. When the vanes 182 are in the closed position, the over-engaging surface 184 rests on the nearest under-engaging vane surface 186. In combination with the vanes `overextension` of the perimeter onto the compliant seal, this produces a fully sealing engagement which effectively shuts off the flow of air through the register assembly 30.
2. Outer Air-deflecting Blades
Also shown in FIG. 5 and FIG. 6 is an array of air-deflecting, outer vanes or blades 180 which may be pivotally attached to the interior frame 34. These blades 180 may be manually set to direct the flow of air to the desired location within the room 42 in which the register assembly 30 is located. The air-deflecting outer blades 180 may be molded or extruded in either a bent or a straight configuration. These blades 180 should to fit in the interior frame 34 of the inner register unit 33, for example, 5" in length At both ends of each blade 180, the blades are pivotally mounted to the frame 30 by pivot pins 181 mounted either on the blades 180 or the frame 30, which snap into mating C-shaped "snap in" receiver 179 mounted on the frame 30 or the blade 180, respectively. This allows for easy assembly and replacement of broken vanes 180. Further, it allows the vanes 180 to be positioned so that the air deflects left or right.
C. Control of the Register Unit
As discussed in connection with FIG. 4, the interlocking vanes 182 are pivotally connected to a blade bar 190. The blade bar 190 may be controlled by a manual lever 188 (as detailed in FIG. 9), or it may be controlled electronically by a servo unit 80. If the blade bar 190 is controlled by a servo unit 80, the servo unit may be connected directly or indirectly via a power assembly 81 and receiving circuit 86, see FIG. 10, to the central controller 60.
1. Hardwired
As shown in FIG. 10, the servo unit 80 has three input wires: a ground wire 95, a power wire 96, and a pulse width wire 97 for receiving a variable signal. In the directly connected electronic embodiment, these wires may be directly "hardwired" to the central controller 60 (at 413, 414, and 415 in FIG. 15a). The wires may run through or alongside the ducts 40.
2. Radio Controlled
Alternatively, the indirect or radio controlled electronic embodiment would include a self-contained power source 81 and a receiving circuit 86 to the servo 80. The receiving circuit 86 preferably receives signals emitted from a radio-type transmitter located in the central controller 60, as discussed below in connection with FIG. 15b. This embodiment would not require "hardwiring" and therefore would add to the ease of retrofitability.
The servo unit 80, as shown in FIG. 10 is preferably fixed to a motor bracket 82. Under or behind the bracket 82, and electronically connected to the servo 80, is the power source 81 which would be used in the self-contained power embodiment. The power source includes batteries 88, the charge of which is maintained by an impeller 94 which is connected to a motor generator 92. The impeller 94 rotates as air passes which causes the generator 92 to charge the rechargeable lithium cells or other batteries such as sealed lead acid cells 88. The lithium cells 88 need to be trickle-charged. However, they are preferable to nicad batteries which have shorter shelf lives than the lithium batteries. The lithium cells 88 are connected to circuit 84 which selectively supplies power to the servo 80 and includes a battery sensor 362 of FIG. 14.
FIG. 14 is a block diagram of the control circuit for a servo equipped register 30. When the battery sensor 362 senses that the batteries 88 need to be charged, a signal is sent to the servo logic 356. The servo 80 then opens the register assembly 30. As air passes through the assembly 30, the impeller 94 turns. This causes the generator 92 to charge the batteries 88.
FIG. 14 further shows the communication means between the register assembly 30 and the central controller 60 in the wireless embodiment. Each servo unit 80 may be equipped with a modular "phone-type" pigtail (approximately one foot long) connected to a female jack. This pigtail may be hardwired directly to the central controller 60 (wires 413, 414 and 415 of FIG. 15a). Alternatively, the pigtail wires (95, 96 and 97) of the servo unit 80 may be connected to the power assembly wires (93, 98 and 94). These wires are preferably connected to a receiving circuit 86 (as seen in FIG. 10), which includes an antenna 366 and a 900 Mhz receiver 350 (as seen in FIG. 14). The receiving circuit 86 picks up signals emitted by the receiver/transmitter 424 of the central controller of FIG. 15b. When the central controller 60 transmits signals to the servo equipped register 30, the signal may then be sent to a wake up unit 358 within the processor 360 and to a spread spectrum logic device 352. The wake up unit 358 signals the spread spectrum logic unit 352, a decoder 354, and a servo logic unit 356. This spread spectrum logic 352 passes the signal to the decoder 354 within the processor 360 which in turn extracts or decodes the original information from the transmitted signal. The signal is sent to the servo logic unit 356 which in turn signals the servo unit 80 to either open or close the appropriate register unit 30.
FIG. 20a shows the hardwire connection (or implied radio signal connection) between the servo 80 which controls the register unit 30 (as shown in FIG. 2) and the central controller 60. The register servo signal from the central controller 60 sends a variable pulse signal 204 (as detailed in FIG. 20b). For example, if the pulse width is approximately 1 millisecond (Ms), the servo is closed. When the signal from the central controller to the servo 80 is 2 Ms, the register unit 30 is opened. Alternate embodiments could include additional, intermediate settings of the servo in which the register unit 30 is partially opened.
III. Individual Zone Thermostat
Each zone 42 which contains a register unit 30 preferably includes an individual zone thermostat 50. Each individual zone thermostat 50 has preferred physical embodiments which are discussed below in connection with FIGS. 11a through 11d. The preferred control scheme of the individual zone thermostat circuit 301 is discussed below in connection with FIG. 13a. If the system 26 is hardwired, the power/communication circuit 348 of FIG. 13a is depicted as 348' of FIG. 13b. If the system is radio controlled, the power/communication circuit 348 of FIG. 13a is depicted as 348" of FIG. 13c. FIGS. 13a, 13b, and 13c will be discussed below.
A. Physical Characteristics
FIG. 11a details a preferred embodiment of the individual zone thermostat 50. The thermostat unit, as shown, may have a digital display screen 100 which could be, for example, approximately 1 inch by 2 inches. The display screen would preferably display information about the current status of the dwelling heating and air conditioning system 26 and the local zone 42. More specifically the display screen 100 of the thermostat unit 50 would highlight information pertinent to the individual room or zone 42. By way of example, information which could be displayed includes: the mode of operation of the system (heat, A/C, "auto" or fan) 102; the status of the system (on or off) 104; the temperature to which the room is set 106; whether the switch actuation is locked 107; the status of the room (on or off) 108; and the actual temperature of the room 109. Also included in the thermostat unit 50 are switch controls for setting the individual zone thermostat 50. By way of example, a mode button 56, an up button 58, and a down button 59 are included in the preferred embodiment of the invention. There is also a hole 57 to provide access to an inner switch for locking the switch actuation. This locking feature is advantageous for use in zones or rooms 42 which small children frequent.
As best shown in FIG. 11b, the individual zone thermostat 50 is equipped with a 110 volt blades or plug prongs 52 for coupling with the standard house receptacle. An alternative means of connecting the thermostat unit 100 to the main system would be the use of a table stand 54 (as best shown in FIG. 11c) into which the plug prongs 52 could be coupled. FIG. 11d depicts another embodiment of the present invention in which the thermostat 50' may be mounted in a junction box 51 and covered with a faceplate 53.
B. Control Circuit
FIG. 13a is a block diagram of the preferred embodiment of the room thermostat circuit 301. The room thermostat 50 is preferably controlled by a microprocessor 300 which may include 4K ROM (four thousand bytes of Read Only Memory). This microprocessor 300 receives information about the zone 42 in which the thermostat 50 is located including the temperature of the room as indicated by a circuit 328, the temperature at which the zone 42 is set, and information on the house and unit (or zone) codes supplied by circuits 322 and 304. The user uses buttons (56, 58, 59 of FIG. 11a), controlled by the switches 320, to set temperature and otherwise communicate with the room thermostat circuit 50. The buzzer 306 provides an audible "beep" to indicate when a button has been depressed. The microprocessor 300 is connected to a display driver 316 which controls the LCD display 318 of the thermostat 50 (as best shown in FIG. 11a). Finally, the room thermostat 50 has a circuit 348 for power and communication.
Information regarding the temperature of the zone 42 is supplied by a thermistor 328. The thermistor 328 changes resistance according to the temperature of the zone 42. A constant current 330 is supplied to the thermistor, and the varying output voltage is then converted from analog to digital form by a serial A/D converter 324. The reference circuit 326 emits a constant 2.5 V as a frame of reference for the system to calibrate the circuit and reliably determine the temperature of a zone 42.
Other information relevant to the microprocessor 300 is obtained from the house code switch 322, the unit or room code switch 304, and the push button switches 320. There is also a power up reset 334 for resetting the thermostat 50, an EEPROM 332, and a LCD display 318 and driver 316 to communicate information to the user. Any time there is a change, i.e. in set temperature or a mode change, this information is stored in the non-volatile EEPROM. If there is a power outage causing the power-up reset to "reset", the EEPROM stored information is utilized when power is restored to place the unit in the last commanded state.
The power communication circuit 348 of the room thermostat circuit 301 is depicted in its hardwired embodiment as 348' of FIG. 13b. In this embodiment, the room thermostat circuit 301 uses the standard house AC wiring 314 for power and for communicating with the central controller 60. Power from the house AC wiring 314 enters the power supply 310. The power supply 310 supplies 5 volts to the room thermostat circuit 301 through a regulator 312. The power supply 310 also supplies 12 volts to the modem 308. The 12 volts are regulated by a zener diode 340. Communication signals may also be sent through the house wiring 314 to and from the modem 308. The modem is controlled by a timing crystal 338 to send and receive messages at 120 KHz. The modem 308 then transfers the message to the room thermostat circuit 301.
In a radio controlled system 26 the power communication circuit 348 of FIG. 13a is depicted as 348" of FIG. 13c. Like the hardwired system 26, the radio controlled system 26 is plugged into standard AC house wiring 314 for power. This power is fed into a power supply 310 which sends a regulated 5 volts to the room thermostat circuit 301. The power supply 310 also supplies 12 volts to a receiver/transmitter 344. The 12 volts are regulated by a zener diode 340. Communication is accomplished via an antenna 342 and a 900 MHz receiver/transmitter 344. The receiver 344 using spread spectrum logic, communicates the information to the room thermostat circuit 301. Information may also be sent from the room thermostat circuit 301 to the central controller 60 via the receiver/transmitter 344 and the antenna 342.
IV. Master Controller
FIG. 12a shows the master controller 70 of the system 26. The primary functions of the master controller 70 is to assist in the programmability of system operation and to change a zone's parameters remotely. Like the room thermostats 50, the master controller 70 may control the temperature of each individual room. The master controller 70, in its preferred embodiment, controls the set temperature of all the rooms to provide separate temperature environments, if desired. The master controller 70 may also control the set temperature in one or all of the zones 42 according to date and time.
A. Physical Characteristics
In the preferred embodiment, the master controller 70 has a display screen 72 and a control pad 74. As seen in FIG. 12b the control pad 74, when not in use, would be covered by door 76. As seen in FIG. 12c the door 76 will be connected by hinging means 79 at the bottom of the master controller 70. The door 76 would be held closed by pull tabs 78 which secure the door to the control pad 74.
The display screen 72 of the master controller 70 (as best seen in FIG. 12a) would include information regarding the status of the dwelling heating and air conditioning system. In FIG. 12a the door 76 is deleted for clarity. Such status information might include various zones 120, current temperatures 122, set temperatures 124, the register status 126, the time at which the system is set to turn on in a particular room 128, the time at which the system is set to turn off in a particular room 130, the days on which the timer is set to turn on 132, and the temperature to which the timer is set to adjust the system 134.
The master control switch pad 74 (as best seen in FIG. 12a) provides various controls for setting and adjusting the dwelling heating and air conditioning system. By way of example, the control pad 74 would include controls for the zone 140, the timer 142, and the clock 144. Other controls could be provided for turning the system on or off 150, for displaying various groups of zones 148, and for labeling the zones 146. The zone controls 140 would include up and down buttons (151 and 152) for the zone under consideration, up and down buttons (153 and 154) for setting the system temperature, and a mode button (155). The timer controls 142 would include up and down buttons (156 and 157) for the "turn on" time, up and down buttons (158 and 159) for the "turn off" time, and up and down buttons (160 and 161) for the timer temperature. Also preferably included in the timer controls 142 would be a button (162) for setting the day, a button (163) to enter the day, a button (164) to clear the timer, and a button (165) to copy the timer information to all zones. The clock set controls 144 would include up and down buttons (166 and 167) for the hour, up and down buttons (168 and 169) for the minute, and a button (170) to set the day. The zone label controls 146 would include left and right buttons (171 and 172) for the cursor, left and right buttons (173 and 174) for the character, a button (175) to restore, and a button (176) to set the memory. The controls for the zone display 148 might include a button (137) for displaying zones 1 through 8 and a button (138) for displaying zones 9 through 15. There would also be a button (150) for turning the system off.
B. Control Circuit
FIG. 19a shows a block circuit diagram of the master controller 70. The master controller circuit 530 is controlled by a microcontroller 534 with timing set by a quartz timing crystal 536. The microcontroller sends out and receives local information over the data bus 552 and address bus 554. The microcontroller circuit may also include 8K RAM 540 which the microcontroller 534 may access. Preferably there is also a PAL switch interface 542 which connects to the buttons on the master controller key pad 74 via switches 550. A timer clock 544 may be included to allow the user to control temperature at specific times of the day. A PAL LCD driver 546 and an LCD 548 make up the components for driving the display screen 72. Finally, a power communication circuit 532 is included to communicate with the central controller 60. The power communications circuit 532 of FIG. 19a is detailed in its hardwired embodiment as 532' of FIG. 19b. The power communication circuit 532 is detailed in its radio controlled embodiment as 532" of FIG. 19c.
The hardwired embodiment of the power communication circuit 532 of the master controller circuit 530 is shown as 532' of FIG. 19b. In this embodiment, the master controller 70 communicates with the central controller 60 via standard house AC wiring 564. Power, also is supplied by the house wiring 564, enters the power supply 560 which sends a regulated 562 5 volts to the master controller circuit 530 and 12 volts to the power line modem 556. The 12 volts are regulated by a zener diode 566. Communication is achieved as signals are sent through the house wiring 564 to and from the modem 556. The modem 556 is controlled by a timing crystal 558 to send and receive messages at 120 KHz. The modem 556 then transfers the signal to the master controller circuit 530.
In a system 26, operated by radio control, the power communication circuit 532 of FIG. 19a is represented as 532" of FIG. 19c. Like the hardwired system 26, the radio controlled system 26 is plugged into standard AC house wiring 564. The AC wiring 564 feeds power into a power supply 560. The power supply 560 provides 5 volts to the master controller circuit 530 and 12 volts to a receiver/transmitter 570. The 5 volts are regulated by the regulating circuit 562 and the 12 volts are regulated by a zener diode 566. Communication is achieved as an antenna 568 picks up signals which are received by a 900 MHz receiver/transmitter 570. The receiver 570 using spread spectrum logic, communicates the information to the master controller circuit 530. Information is also sent from the master controller circuit 530 to the central controller 60 via the receiver transmitter 570 and the antenna 568.
V. Central Controller
The central controller 60 preferably provides the central point of communication and control for the heating and air conditioning system 26. The central controller 60 may communicate with the individual zones 42 by sending out "instructions" to each thermostat 50. It may also receive "responses" as to the "temperature state" of each thermostat 50. The central controller 60 communicates with the master controller 70 by sending out "instructions" and receiving "responses." Another important function of the central controller 60 is to control the servo controlled room registers 30. Finally, the central controller 60 turns on and off the heater, air conditioning system, and fan 44 as needed, based on the "in condition" of the individual thermostats 50.
FIG. 15a shows the preferred embodiment of the central controller 60 in a hardwired system 26. FIG. 15b details the preferred embodiment of the central controller 60 in a radio controlled system 26. FIG. 16 shows the preferred embodiment of a sequence of steps that the central controller 60 takes to accomplish its functions. The steps may be dictated by a program in the memory (390 and 400) of the central controller 60. FIG. 18 details the communication "instructions" and "responses" used by the central controller 60.
A. Control Circuit
As shown in FIG. 15a and 15b, the central controller 60 is equipped with a microprocessor 400 which has its timing controlled by a quartz timing crystal 416. Extra non-volatile memory is provided by an EEPROM 390, for back-up purposes as disclosed hereinabove. The preferred program stored in ROM is discussed below in connection with FIG. 16.
Information regarding the temperature is supplied by a thermistor 394. The thermistor 394 changes resistance according to temperature. A constant current 392 is supplied to the thermistor, and the varying output voltage is then converted from analog to digital form by a serial A/D convertor 398. The reference circuit 396 emits a constant 2.5 volts as a frame of reference for the system to calibrate the circuit and reliably determine the proper temperature. Other information relevant to the microprocessor includes a power up reset 386, and a house code switch 388.
The microprocessor 400, based on information it receives from the room thermostats 50 and the master controller 70, controls the furnace and air conditioner 44. This is done by three triac units 404 which control the heat, air, and fan (406, 408, and 410). The microprocessor 400 can also control the speed of the fan by using a motor speed control unit 402 to control the HVAC 426.
FIG. 15a specifically embodies the configuration of a central controller 60 which is hardwired to the system 26. The register servos 80 are hardwired (414 to 96, 415 to 97, and 413 to 95 as shown in FIG. 15a and FIG. 10) in queue fashion 412 to the microprocessor 400. This enables the central controller 60 to poll the register servos one at a time. The microprocessor 400 communicates to the room thermostats 50 via a quartz crystal 418 controlled modem 384 which sends out signals via standard AC wiring 420. The AC wiring 420 is also connected to a transformer 382 which in turn is connected to a power supply 380 which supplies power to the central controller 60.
FIG. 15b shows the radio controlled embodiment of the central controller 60. Communication to the master controller 70, the room thermostats 50, and the servo controlled registers 30 is done using radio signals. The microprocessor 400 sends and receives signals to and from a 900 MHz receiver/transmitter 424 which uses spread spectrum logic and over an antenna 422 to an appropriate device. Signals from these devices are received through the antenna 422 and the 900 MHz receiver/transmitter 424 and return to the microprocessor 400 for processing. This radio controlled central controller 60 is powered by standard house AC wiring 420. The power goes through a transformer 382 to a power supply 380 which supplies power to the central controller 60.
B. Control Steps
FIG. 16 is a block diagram of a preferred embodiment of the program contained in the ROM of the central controller 60. Once the power has been turned on 430 the compressor timer is preferably set to five minutes 432. This five minute period allows the pressure in the compressor to equalize and thereby prevents damage to the compressor. A check may then be done on the data integrity and the backup EEPROM 434. If the check comes out "bad," the HVAC is turned off 450. If, however, the check comes out "good," then the temperature setting and status is sent to all the remote register units 436. A signal is then sent out to the servo controlled registers 30 so that all the vents are closed 438. The timer is then set for a 3.5 minute countdown 440.
After the countdown, a loop is preferably begun which requests the status, the temperature setting, and the current temperature from the zone (1-16) at which the loop is working 442. If there is no reply from the current zone, the program looks at the integrator of the current zone 444. Each of the 16 zones has an integrator which resets to 5 after each reply on the zone. If, however, there is no reply, the integrator is decremented by 1. Each time there is no reply from the current zone remote thermostat, and the integrator is greater than zero, the program may assume the status quo. If, however, the integrator is zero, the program may assume the room is off status.
The program may then check to see if the current status of the system equals the remote status 446. If the current status does not equal the remote status, then the system status may be changed to the remote status 448, the change may be broadcasted to all of the remotes 456, and the next zone (1-16) may receive a request for status, setting, and current temperature 442 from the system. If, however, the current status equals the remote status 446 then the program reacts based on that status (458, 460, 462, 464, and 466).
If the status of the system is the heating mode 458 then the program preferably looks to see if the temperature is less than or equal to the set temperature by 2° or more 468. If it is less than the set temperature by 2° or more and the heat is on, then the system may open the vent 478. If it is not less than the set temperature by 2°, the vent may be closed 476. However, if this is the last active heat zone, the heat may be turned off 476.
If the status of the system is the air conditioning mode 460, then the program may compare to see if the temperature is greater than or equal to the set temperature by more than 2° 470. If the temperature is greater than the set temperature by more than 2°, the vent may be opened and the air conditioning may be turned on if the compressor timer is equal to zero 482. If the temperature is not greater than or equal to the temperature by 2° or more, then the vent may be closed. If this is the last active air conditioning zone, the air conditioning may be turned off and the compression timer is preferably started at five minutes 480.
If the status is set to the fan mode 462, then the fan may be turned on and the vent may be opened 472. If the status is set so that the room is turned off 464, then the vent may be closed, unless it is the last vent polled 474. If the status of the system is that the system is turned off 466, then the entire heating, ventilation, and air conditioning (HVAC) may be turned off 450.
If this is not the last zone to be polled 484, then the next zone may be looked at 442. However, if this is the last zone to be polled 484 and the number of active vents is less than 50% of the total vents, then the slow blower motor may be turned on if the system is in the air conditioning mode 486. The system may then look to see if there is a master controller 488 included in the system. If there is a master controller, the program may look to see if the data in the master controller matches the data in the central controller 490. If it does not match, then the remotes that differ are updated 492 and the next (first) zone is examined 442. If the data in the master controller matches the data in the central controller 490, the program may then look to see that the plenum temperature is below 34° 452. If there is no master controller 488, the system immediately checks the plenum temperature 452.
If the plenum temperature is not below 34°, then the timer countdown may be started at 3.5 minutes 440. If the plenum temperature is below 34° 452, if the air conditioning is on, then it is turned off and the compressor timer may be set 454. If, however, the air conditioner is not on, then this step may be ignored. Either way, the timer countdown is preferably set to 3.5 minutes.
C. Control Communications
As mentioned above, the central controller 60 may communicate with the thermostats 50, the master controller 70 and the register units 30 via radio signals or through house AC wiring and hardwiring run through the air ducts.
The actual signals would preferably be analog signals. For example, FIG. 17b represents an analog high frequency signals transmitted over AC 120 volts house wiring. The figure shows a signal which represents a one 508 and a signal which represents zero 510. FIG. 17a represents the analog signals converted to digital one 504 and digital zero 506 which corresponding to the analog signals. Digital ones 504 and zeros 506 are strung together to form 8 bit hex words which, in turn, are strung together to form instructions and responses. The instructions are detailed in FIG. 18.
The central controller 60 sends out various instructions. Each instruction preferably has a standard 8 bit starting word, for example, AA. Each instruction transmission preferably has a standard 8 bit ending word, for example, BB. The instruction preferably includes an 8 bit word indicating the instruction type. Other 8 bit words which may be included in an instruction are the house code, a vent or register code, a status code, an offset code, a parity or check sum (cksum) code, a new temperature setting code, and a master controller code. Instruction types may include a request status, an update status, a broadcast command (to all thermostats), a temperature set offset (which would be done at the factory to calibrate the variation found in silicon chips), a query for the master controller, and instructions to the master controller. This list is meant to be exemplary, and is not meant to be limiting.
The thermostat 50 may send responses to the central controller 60 by a similar string of 8 bit hex words. The response may begin with a standard 8 bit hex word different from the starting word of the central controller instruction, for example, 55. The transmission may end with a standard 8 bit word, for example, BB. Other 8 bit words in a thermostat response may include a house code, a thermostat code, a status code, a temperature set code, a current temperature code, and a parity or check sum code. If there was more than one type of thermostat response, a response "type code" may also be included.
The master controller 50 may send responses to the central controller 60 by a similar string of 8 bit hex words. The response may begin with a standard 8 bit hex word different from the starting words of the central controller instruction or the thermostat response, for example, CC. The transmission may end with a standard 8 bit word, for example, BB. Other 8 bit words in a master controller response may include a house code, a thermostat count code, a status code, a temperature set code, and a parity or check sum code. If there was more than one type of master controller response, a response "type code" may also be included.
VI. Conclusion
In conclusion, it is to be understood that the present invention is not to be limited to that precisely as described hereinabove and as shown in the accompanying drawings. More specifically, the exterior frame 32 may be a molded unit, the side units 38 of the exterior frame 32 may be made of extruded metal, the power assembly 81 may be replaced by alkaline or nicad batteries, the thermostat units 50 may be hardwired to the central controller 60, the central controller 60 may have a programmable key pad, or the buttons in the thermostat 50 and master controller 70 could be replaced by other known forms of display and control. A simplified system could combine the master 70 and central 60 controllers. Further, the electrical circuits show preferred implementations, but the described functions may be accomplished by other equivalent circuity. The system may also be operated in an "AUTO" mode in which the system recognizes needs for heating and cooling and automatically may switch between heating and cooling modes of operation. Also a master controller may be combined with a zone thermostat. Accordingly, the present invention is not limited to the arrangements precisely as shown and described hereinabove. | A retrofittable heating and air conditioning system for a single family dwelling including a heater and air conditioning furnace system connected to individual zones of a building by a series of output ducts. Each opening of a duct to an individual zone may have a unique, fully sealing, controllable output register assembly. Also, in each zone is a thermostat for sensing the zone temperature and for providing a means for the user to control the temperature of that zone. The system further includes a master controller with such temperature controlling features as a universal zone controller, individual zone controllers, and a timer. Finally, the system includes a central controller for controlling the register assemblies and the air conditioning, heating, and fan with respect to instructions set by the individual zone registers and the master controller. | 4 |
BACKGROUND OF THE INVENTION
The packaging of goods has developed to a point where certain goods are no longer packaged in symmetrical containers, rather some goods are packaged in containers wherein a filling and discharge aperture or spout is offset from the center of the container. These containers often are made of a lightweight plastic material to reduce the handling costs and to provide an inexpensive container. In the manufacture of containers of this general type, the containers are randomly discharged into a large holding container. In order to utilize modern packaging and labeling equipment, it is necessary to arrange the containers so that the containers are not only aligned in the same direction, but also that each container has the same relative position as each other container, that is, if a spout is offset, all of the spouts are arranged in the same direction. An apparatus for aligning containers vertically is taught in U.S. Pat. No. 3,650,368, issued Mar. 21, 1972, entitled, "Article-Orienting Apparatus", to John C. Nalbach. The mentioned patented article orienting apparatus does not position the containers so that each container is aligned with each asymmetrical portion in the same relative position. It is therefore necessary to position selectively the containers. The heretofore known apparatus rotates selected containers 180° in one movement to align all of the containers. Inasmuch as the containers are lightweight, and the containers are rotated 180° in a single movement, there is a tendency for the containers to tip and fall. When containers fall, the container may knock over a number of other containers through a domino effect and thereby disrupt the smooth operation of a packaging facility.
SUMMARY OF THE PRESENT INVENTION
The present invention relates to an apparatus for orienting substantially identical containers. Each of the containers has a base for holding the container upright. Each container is asymmetrical in a plane substantially perpendicular to the base. The containers are delivered to the apparatus in a single line, but the position of the asymmetrical plane is random. The containers are carried by a longitudinal conveyor to a first turning assembly. The first turning assembly aligns all of the containers so that the asymmetrical plane of each container is parallel to the direction of movement of the longitudinal conveyor. When the containers are discharged from the first turning assembly, a detector senses the position of the asymmetrical plane of each of the containers. A second turning assembly which is in part controlled by the detector, rotates each container approximately 90° either in a clockwise or counterclockwise direction to align all of the containers leaving the second turning assembly in a line with the asymmetrical planes being in the same relative position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a container orienting apparatus embodying the herein disclosed invention;
FIG. 2 is a plan view of an upper portion of the apparatus of FIG. 1 showing the interrelationship of the various drive portions;
FIG. 3 is a cross-sectional view taken on Line 3--3 showing a portion of the drive shown in FIG. 2 and showing a fragmentary portion of a screw conveyor of the present apparatus;
FIG. 4 is a partial cross-sectional view taken on Line 4--4 of FIG. 3 showing containers moving between a pair of screw conveyors;
FIG. 5 is a fragmentary portion of FIG. 4 showing a second turning assembly in operation to rotate a container in a clockwise direction;
FIG. 6 is an end elevational view of an entry portion to a pair of screw conveyors and showing a portion of a drive;
FIG. 7 is a fragmentary perspective view showing a portion of an exhaust assembly to create a negative pressure over a portion of a longitudinal conveyor; and
FIG. 8 is a fragmentary perspective view showing platens which make up a portion of a longitudinal conveyor showing the apertures in the platens.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and especially to FIG. 1, a container orienting apparatus embodying the herein disclosed invention is shown therein and is generally indicated by numeral 10. Apparatus 10 generally includes; a frame 12, a longitudinal conveyor 14 mounted on the frame, a drive 16 mounted on the frame and connected to the longitudinal conveyor, a first turning assembly 18 mounted on the frame and connected to drive 16, a detector assembly 20 mounted on the frame above a portion of the longitudinal conveyor, a second turning assembly 22 positioned adjacent to the first turning assembly and having a portion controlled by the detector assembly, and an exhaust assembly 24 having a portion cooperative with the longitudinal conveyor to create a negative pressure over a selected portion of the conveyor.
Frame 12 is conventional in its construction in that it includes four uprights 26, 28, 30 and 32, and an upper portion 34 supported by the uprights. The upper portion supports drive 16. Four brackets 36, 38, 40 and 42 interconnect the uprights between the upper portion 34 and the bottom of the uprights. The frame includes a conveyor box 44 which is fixed to uprights 26 and 32, and is supported by leg 45.
Looking now to FIGS. 1 and 2, a portion of drive 16 is shown therein. Drive 16 includes a pair of drive supports 46 and 48 mounted on the frame. Drive support 46 includes a table 50 which has a discharge end 52 fixed thereon. Discharge end 52 extends downwardly to approximately the level of the longitudinal conveyor. Table 50 has an entry support 54 at the other end thereof. The entry support is positioned on the same level as the longitudinal conveyor, as may be best seen in FIG. 6. Table 50 includes a pair of slots 56 and 58 adjacent to the discharge end. Table 50 also includes a pair of slots 60 and 62 adjacent to the inlet end. A nut 64 is fixed to the lower surface of table 50 between slots 56 and 54. A like nut 66 is fixed to the bottom of table 50 between slots 60 and 62. Bolts 68 and 70 are threadedly mounted in the upper portion 34 and are slideably positioned in slots 56 and 58, respectively. Bolts 72 and 74 are threadedly mounted in upper portion 34 and are slideably mounted in slots 60 and 62. The bolts 68, 70, 72 and 74 are used to lock the table to the upper portion.
Drive support 48 includes a table 76 which has a discharge end support 78 fixed to one end of table 76. An entry end support 80 is fixed to the other end of table 76. Table 76 includes a pair of slots 82 and 84 which are substantially identical to slots 56 and 58. Bolts 83 and 85 are threadedly mounted in the upper portion and are slideably mounted in slots 82 and 84, respectively. Table 76 includes a pair of slots 86 and 88 adjacent to the entry end of table 76 and those slots are substantially identical to slots 60 and 62. Bolts 87 and 89 are threadedly mounted in the upper portion and are slideably mounted in slots 86 and 88, respectively. Tightening of bolts 83, 85, 87, and 89 locks table 76 to the upper portion. A nut 90 is fixed to the bottom of table 72 between slots 82 and 84. A like nut 91 is fixed to the bottom of table 76 between slots 86 and 88. A shaft 92 is rotatably mounted in a bearing 93 which is supported on the upper portion. Shaft 92 is connected to a threaded portion 94 having right-hand and left-hand threads and is threadedly mounted in nuts 64 and 90. A sprocket 96 is fixed to one end of shaft 92. A like shaft 98 is mounted in a bearing 100. Shaft 98 has a threaded portion 102. Threaded portion 102 has right-hand and left-hand threads which are connected to nuts 66 and 91. Shaft 98 has a sprocket 104 fixed to one end thereof. Sprocket 104 is connected to sprocket 96 by a conventional chain 106. Sprocket 104 includes a crank 107 to crank the sprocket. As sprocket 104 is turned, it drives sprocket 96 for selectively moving tables closer together or further apart as may be desired through the interaction of the threaded platens of shafts 92 and 98 with the nuts fixed to the bottom of tables 50 and 76.
An electrical motor 108 is mounted on the upper portion. Motor 108 has a sheave 110 mounted on its output shaft. The motor is mounted on upper portion 34 so as not to interfere with movement of tables 50 and 76. A drive shaft 112 has a portion mounted in a bearing 114. The drive shaft has a splined portion 116. A pulley 118 is secured to drive shaft 112. A belt 120 drivingly connects sheave 110 with pulley 118. A drive sheave 122 is fixed to the end of drive shaft 116. A belt 124 is connected to sheave 122. The belt engages an idler pulley 126 mounted on the frame and a conveyor drive pulley 128. The conveyor drive pulley is connected to a gear box 130 which has a conveyor drive shaft 132 connected thereto. The conveyor drive shaft 132 is connected to a conveyor gear box 134 which is connected to a conveyor sprocket 136 to drive longitudinal conveyor 14.
Drive shaft 116 is connected to a pair of vertical gear boxes 138 and 140. Gear box 138 is connected to a vertical drive shaft 142, which in turn is drivingly connected to a screw drive 144. Gear box 140 is connected to a vertical drive shaft 146 which is connected to screw drive 148. Screw drives 144 and 148 are mounted on end supports 80 and 54, respectively, as may be best seen in FIG. 6.
Conveyor 14, as may be best seen in FIGS. 1 and 8, is made up of a plurality of identical individual platens 150. Each of the platens contains four apertures 152 which allow air to pass through each of the platens. Each platen is connected to adjacent platens by hinges 154. The platens are driven by sprocket 136 to move the conveyor longitudinally over conveyor box 44. Conveyor box 44 has a closed bottom 156 and a pair of sides 158 and 160. The box has a top 162 with an opening 164 formed in the top.
Exhaust assembly 24 is connected to the conveyor box. The exhaust assembly includes a pair of conduits 166 which open into wall 160. The conduits 166 are interconnected by tube 168 to a connector 170 which is in turn connected to a flue 172. The flue 172 is connected to a conventional centrifugal exhaust fan 174. Thus, air is pulled through the apertures 152 into conveyor box 44 and to the exhaust fan creating a negative pressure over the outside upper surface of the longitudinal conveyor.
First turning assembly 18 is shown in FIG. 4. The first turning assembly includes a pair of screw conveyors 176 and 178. Screw conveyor 176 has a tapered screw surface 180 mounted on a screw shaft 182 which screw shaft is drivingly connected to screw drive 144. As may be seen in FIG. 4, outer screw surface 180 has a tapered right-hand screw thread 184 formed thereon. The screw thread has a decreasing lead from the entry end to the discharge end; however, the depth of the thread increases from the entry end to the discharge end.
Screw conveyor 178 is mounted on a screw shaft 188 which screw shaft is drivingly connected to screw drive 148. Screw conveyor 178 includes an outer surface 190 which has a tapered left-hand thread 192 formed thereon. Surface 190 with thread 192 is a mirror-image of surface 180 and screw thread 184. The screw conveyors are rotated in opposite directions toward each other at the same rate of rotation.
Screw conveyors 176 and 178 are positioned adjacent to each other as shown in FIG. 4, and define an entry 194 to allow containers to enter between the screw threads and to rotate containers between the threads so that the containers are rotated approximately 90° when the containers reach a discharge 196 at the other end of the screw conveyors.
Detector assembly 20 includes a conventional electric eye 198 mounted on discharge end 52 adjacent to the discharge of the screw conveyors. A second conventional electric eye 200 is mounted on discharge end 78 opposite the first mentioned electric eye 198. The electric eye 198 and 200 are focused to detect the presence of a portion of a container at a given distance. Thus, if a portion of an asymmetrical container is positioned closer to electric eye 200, the electric eye 200 will detect the presence of the portion of the container, whereas electric eye 198 will not detect the presence of a portion of a container.
The second turning assembly 22 includes a helical turning blade 202 which is mounted on a hub 204 connected to screw conveyor 178 for rotation with the screw conveyor. The turning blade extends above a portion of the longitudinal conveyor to engage each container discharged by the screw conveyors through discharge 196. The second turning assembly also includes stop fingers 206 which are connected to a conventional solenoid 208. Stop fingers 206, in its retracted mode, are positioned away from the longitudinal conveyor, as may be seen in FIG. 4. When solenoid 208 is activated, stop fingers 206 are extended over a portion of the longitudinal conveyor to engage a container carried on the longitudinal conveyor, as may be best seen in FIG. 5.
The instant apparatus includes conventional entry guide rails 210 positioned adjacent to the entry end of the screw conveyors to aid the containers to remain upright. Exit guide rails 212 extend from the discharge end of the screw conveyors to the end of the longitudinal conveyor.
The instant apparatus is adapted to handle containers of various sizes. The spacing between the screw conveyors may be adjusted by loosening the bolts holding tables 50 and 76. Sprocket 104 is cranked in a selected direction to move the tables 50 and 76 and thereby position the screw conveyors apart or closer together as is required. The drives for the screw conveyors are connected through spline 116 on drive shaft 112, so that the tables may be moved relative to each other moving not only the screw conveyors, but the entire drive mechanism from the drive shaft 112 onward.
The rate of movement of the longitudinal conveyor from one end of the frame to the other and the rate of movement of a container through the screw conveyors can be selectively adjusted by adjusting the gear boxes 138 and 140. In this instance, the rate of movement of the longitudinal conveyor is greater than the rate at which containers are carried through the screw conveyors so that the containers are continually pressed into engagement with the threaded portion of the screw conveyors. The rotation of the screw conveyors toward each other applies a downward force to the containers in engagement with the screw conveyors. In view of the fact that the screw conveyors and the longitudinal conveyors are driven from the same source, namely, electrical motor 108, it is evident that the relative rate of movement between the longitudinal conveyor and the screw conveyors is maintained at a constant selected ratio.
For purposes of illustration, containers 214 are shown and described in connection with the operation of the present invention. It is to be understood that any of a variety of containers may be utilized with the present apparatus. Each of the containers 214 is, in this instance, a blow molded plastic container having a base 216 which supports the container. The base has an outer wall 218 formed integral therewith. The outer wall has a mouth 220 formed in the upper portion thereof. Mouth 220 is offset from the center, as may be best seen in FIGS. 1 and 4. Containers 214 are asymmetrical in a plane which is substantially perpendicular to base 216. The subject apparatus aligns all of the containers 214 so that the relative position of the mouth 220 of each container is in the same relative position of each other container after leaving the second turning assembly.
Containers 214 are loaded onto longitudinal conveyor 14 between entry guides 210. The containers are all aligned when entering the longitudinal conveyor so that the plane of asymmetry of each container is parallel to the direction of movement of the longitudinal conveyor. The position of the mouth of each container is random in that the mouth may be either adjacent to the leading edge or the trailing edge of the plane of asymmetry of each container as generally indicated in FIG. 4.
The base of each of the conveyors rests on one or more platens 150 and air being drawn through apertures 152 causes the base to be held securely onto the platens so that the containers are not likely to tip and fall. The containers are carried by the longitudinal conveyor to entry 194 of the screw conveyors. The longitudinal conveyor moves the containers toward the screw conveyors faster than the screw conveyors allow the containers to move between the screw conveyors so that the containers are constantly urged into engagement with screws 184 and 192. As the containers are pushed into the screws, they are turned by the screws so that the containers are rotated 90° between the screw conveyors. The containers approach discharge 196 traveling on the longitudinal conveyor with the plane of asymmetry substantially perpendicular to the direction of movement of the longitudinal conveyor. Throughout the rotation of the containers between the screw conveyors, the containers are supported by both screw conveyors to stabilize the containers and minimize the likelihood of tipping.
As the containers are carried to discharge 196, the containers pass by detector assembly 20. In the event that a container such as specific container 222, is positioned between the electric eyes 198 and 200, electric eye 200 strikes the mouth of container 220. The container is discharged, and the container then engages helical turning blade 202. The longitudinal conveyor moves the container forward while the edge of the container adjacent to electric eye 198 is retained by the helical turning blade which engages the containers adjacent to the center of gravity of the containers to reduce the likelihood of tipping of the containers. The rate of rotation of the helical turning blade is such that the container is allowed to move forward, but the edge which engages the turning blade does not move as fast as the longitudinal conveyor is moving the container. Thus, the container is rotated in a counterclockwise direction, as shown in FIG. 4 with the containers shown in dotted form in stages of rotation.
In the event that a container, such as container 224, is positioned between the electric eyes 198 and 200, the electric eye 198 then detects that the mouth is closer to electric eye 198. Solenoid 208 is energized to extend fingers 206 to the position shown in FIG. 5. The longitudinal conveyor still tends to move the container at the rate of the longitudinal conveyor; however, fingers 206 are stationary, and the fingers engage one edge of container 224 adjacent to the center of gravity of the conveyor to reduce the likelihood of tipping of the containers. The opposite edge of the container engages helical turning blade 202, which allows that edge to move but at a slower rate than does the longitudinal conveyor. This arrangement results in the container having one edge held stationary by fingers 206 while the opposite edge is allowed to move, but at a slower rate than the rate at which the longitudinal conveyor moves. Thus, the container is rotated in a clockwise direction, as shown in dotted form in FIG. 5.
It is readily apparent that irrespective of whether the container is rotated in a clockwise direction or a counterclockwise direction in the second turning assembly, it is turned at a slow rate until the asymmetrical plane of the container is parallel to the direction of movement of the longitudinal conveyor. The rate of turning it is the difference between the rate of movement of one edge of the containers and the other edge of the same containers. In the case of counterclockwise rotation, the rate of turning is determined by the lead and rate of rotation of the turning blade relative to the rate of longitudinal movement of the longitudinal conveyor. In the case of rotation in a clockwise direction, the rate is determined by the lead of the helical turning blade and the rate of rotation of the helical blade. In either case, once the turning is completed at a slow rate and the containers are aligned with their asymmetrical planes in line with the mouths all in the same relative position, the containers are then carried away at the rate of the longitudinal conveyor. The containers are supported by discharge guides 212. At all times in the critical movements, the containers are rotated at a slow rate and as the containers are rotated, the rate of rotation is controlled by the rate of turning of the helical turning blade. Thus, the likelihood of tipping or other disorientation of the containers is substantially decreased.
Although a specific embodiment of the herein disclosed invention has been shown and described in detail above, it is readily apparent that those skilled in the art may make various modifications and changes in the instant invention without departing from the spirit and scope of this invention. It is to be expressly understood that this invention is limited only by the appended claims. | The present invention relates to an improved apparatus for orienting substantially identical containers. Each container has a base for supporting the container. Each container is asymmetrical in a plane substantially perpendicular to the respective base. The apparatus includes a longitudinal conveyor for moving the containers from one end of a frame to the other. A first turning assembly is mounted on the frame to turn the containers relative to the longitudinal conveyor to arrange the containers in an attitude wherein the asymmetrical plane of each container is parallel to the direction of movement. An attitude detector apparatus is positioned adjacent to the discharge end of the first turning assembly and detects the attitude of containers discharged. A second turning assembly rotates the containers discharged from the first turning assembly 90° either clockwise or counterclockwise in response to a signal from the attitude detector to align all of the containers in the same attitude. | 1 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
The United States Government has certain rights in this invention pursuant to Department of Energy Contract No. DE-AC04-94AL85000 with Sandia Corporation.
FIELD OF THE INVENTION
The invention generally relates to the patterning of aerogels that are very porous materials, with low refractive index, and are produced by sol-gel processing. The invention further relates to methods for etching sharply defined patterns in porous aerogel films disposed on a substrate. The methods overcome the limitations of irregularly edged features typically produced when traditional photolithographic methods are applied to porous materials.
BACKGROUND OF THE INVENTION
Aerogels are very porous nanostructured materials typically prepared by sol-gel processing. Typical aerogels can exhibit up to 99% porosity, low refractive index (η<1.1) high surface area (>1000 m 2 /g), and small pores (<10 nm). Aerogels generally comprise dielectric materials such as the oxides of silicon, aluminum and titanium, and can also include organic polymers. Aerogels have many applications including catalyst supports, electrical insulators, thermal insulators, and acoustic insulators. It is desired in many applications to employ an aerogel material as a film (e.g. a layer on the order of 1 um thick) on a substrate (e.g. glass, silicon, metal, ceramic, etc.) in applications ranging from the fabrication of micro-electromechanical (MEM) devices to optical display and solar energy conversion devices. In many of these applications it is required that the aerogel film be patterned on the surface of the substrate, creating sharply defined, exposed areas (e.g. aerogel removed) on the substrate and adjacent unexposed areas (e.g. areas remaining covered by the aerogel layer) on the substrate. Due to the porous nature of the aerogel layer, traditional photolithographic techniques typically produce poorly defined pattern edges between the exposed and unexposed areas of the substrate. What are needed are methods that overcome this limitation and allow the creation of sharply defined patterned features of aerogel layers on the surface of the substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the invention.
FIG. 1 is a schematic flow chart of an embodiment of a method according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Bulk aerogels are typically made by the super critical solvent extraction of a fluid containing gel (e.g. precursor sol, or simply sol) in a high pressure autoclave in excess of 1100 psi. Processing gels under supercritical conditions avoids the collapse of the porous gel structure due to drying shrinkage, driven by the forces of capillarity that occur in ambient pressure solvent evaporation. Commonly owned U.S. Pat. No. 5,565,142 herein incorporated by reference in its entirety, discloses methods for making bulk aerogels at ambient temperature and pressure that avoid super critical processing and allow drying at ambient pressures and temperatures. These methods produce an organic modification of the gel pore surfaces that enhance hydrophobicity, greatly reducing the forces of capillarity and thereby preventing gel collapse during drying.
An extension of this work is described in commonly owned U.S. Pat. No. 5,948,482 herein incorporated by reference in its entirety, which describes methods to deposit aerogel thin films by either spin, dip or spray coating onto the surface of a substrate, again avoiding the need for super critical drying. These aerogel thin films are also highly porous and have applications in chromatography, fluidics, sensors, optics, electronics, and additionally as selective absorbents, inorganic hosts for bioactive species, catalysts, and membranes. The films produced by the methods disclosed are of uniform thickness and can be on the order of one micron (1 um) thick per coating operation.
Commonly owned U.S. Pat. No. 7,485,343 herein incorporated by reference in its entirety, discloses methods for preparing hydrophobic coatings on the surface of a substrate by exposing an aerogel film deposited on the substrate to vapors of hydrophobic silane compounds, such as hexamethyl disilazane (HMDS). Exposure of an aerogel to HMDS vapor results in a further organic modification of the pore surfaces of the aerogel, forming what have come to be called “super hydrophobic” coatings which can exhibit water contact angles of greater than 150°. Further described are methods for creating patterns of hydrophilic areas on the coated surface of the substrate by exposing the hydrophobic coating to ultraviolet (UV) irradiation. Exposure to UV radiation generates ozone in the pores of the hydrophobic aerogel which oxidizes the organic modification of the pore surfaces, returning the aerogel surface to a more hydrophilic state (i.e. having a reduced water contact angle).
The methods according to the present invention take advantage of the ability to create hydrophobic and hydrophilic areas on the surface of an aerogel coated substrate to provide for patterning the aerogel film by use of aqueous reagents. Wherein desired areas of the aerogel film are removed by etching (e.g. subtractive processing) exposing the underlying substrate and leaving behind a patterned aerogel film disposed on the surface of the substrate. The methods according to the present invention have been found to produce features (e.g. lines) with sharper edges than can be realized using traditional photolithographic methods.
Aerogel films as-deposited onto a substrate are somewhat hydrophobic. This hydrophobicity can be eliminated by exposing the as-deposited aerogel film to an ultraviolet (UV) light source (e.g. λ˜185 nm). The UV light reacts with the ambient atmosphere to generate ozone in the pores of the aerogel which oxidizes the organic modification on the internal pore surfaces. The resulting hydrophilic aerogel film pores (i.e. those exposed to UV/ozone treatment) can now be wetted by water and/or aqueous etchants while the hydrophobic aerogel pores (i.e. those not exposed to UV/ozone) are not wetted.
To pattern the as-deposited aerogel into hydrophobic and hydrophilic regions a patterned metal mask on silica (e.g. an etched chrome photomask) as typically used in microelectronic manufacturing, can be placed proximal to (e.g. near or in direct contact with) the aerogel film, preferably with the metal side of the mask in contact with the aerogel film. The “masked” aerogel film can then be exposed to UV illumination. The metal areas of the mask prevent UV light from impinging on the aerogel film and no ozone is created in the pores, while the clear areas of the mask allow UV light to impinge on the film and create ozone in the illuminated pores. The illuminated areas of the aerogel film therefore form a pattern of hydrophilic material (i.e. aerogel) that can be etched by aqueous reagents. If the UV exposure through the clear areas of the mask is not long enough the organic modification remains on the surface of the aerogel and the aerogel remains hydrophobic. If the exposure through the mask is too long ozone can diffuse laterally into the masked regions of the aerogel film enlarging the hydrophilic aerogel region causing the etched aerogel areas to be too large.
Water can cause the collapse of the hydrophilic aerogel when it is dried leaving a silica residue on the surface of the substrate (e.g. in the case for a silica based aerogel). Various concentrations of hydrofluoric acid etchants were tried unsuccessfully to fill the pores and etch the silica. It was found however that a glass etchant of 1 molar sodium hydroxide was able to remove the hydrophilic regions of the aerogel film and not leave a silica residue, however this etchant also slightly etched the hydrophobic aerogel regions. This can reduce the sharpness of the aerogel pattern, a condition referred to as over etching.
The etching of the as-deposited hydrophobic aerogel by 1 molar sodium hydroxide etchants and resultant over etching can be eliminated by enhancing the hydrophobicity of the as-deposited aerogel film. After aerogel film coating of the substrate and before exposure to UV the coated substrate is placed in hexamethyl disilazane (HMDS) vapors (i.e. an organofunctional silane). This insures a more complete organic modification of the aerogel surface. This was found to greatly reduce the over etching problem.
FIG. 1 is a schematic flow chart of an embodiment of a method according to the present invention. Method 100 begins at step 102 where a substrate, such as a glass blank or silicon wafer is cleaned and dried. A typical cleaning process for a glass substrate can include, scrubbing the substrate using a solution of water and an alkaline cleaning agent, rinsing the substrate with tap water then thoroughly rinsing the substrate with deionized (DI) water, followed by blowing the substrate dry with filtered nitrogen. A plasma cleaning operation (e.g. 20 minutes in oxygen plasma) can be employed to further remove trace organic contaminants from the surface of the substrate.
At step 104 the substrate is coated with an aerogel sol by spin, dip or spray coating the aerogel sol onto the substrate. In an exemplary embodiment, silicate sols were prepared by the methods described in the '482 patent (incorporated above). Silicate sols were produced from tetraethoxysilane (TEOS) dissolved in ethanol using a two step acid/base catalyzed procedure. Sols comprising aluminum or titanium oxides could be used as well. The prepared sols were aged at 50° C. in an oven having an ambient atmosphere to form the gel structure. The aged gels were then subjected to a pore fluid washing procedure, wherein the original pore fluid (water and ethanol) was ultimately replaced with hexane and a silylating reagent, in this exemplary embodiment hexamethyl disilazane (HMDS). This procedure results in surface derivatization of the pores in the gel by reaction of reactive terminal sites with HMDS (i.e. organic modification of the pore surfaces). The surface-derivatization was followed by reliquification of the gel using ultrasound (e.g. sonification). Glass and silicon wafer substrates were then dip coated into the reliquified gel.
At step 106 the coated substrate is heated to drive off the solvents. Heating can be accomplished on a hot plate and typically takes less than one minute. In this example, the hot plate was heated to 180° C.
At step 108 the coated substrate is exposed to hexamethyl disilazane (HMDS) vapors for approximately ten minutes. HMDS vapors were generated by flowing nitrogen gas through a bubbler thereby saturating the gas with HMDS which is directed to flow over the surface of the substrate while on a hot plate. In this example, the hot plate was heated to 180° C. This step insures the surface of the aerogel coated substrate is hydrophobic, which enhances the sharpness of the eventual patterns formed. This step can be considered as a second derivatization process to attach silane groups to reactive sites on the pore surfaces that may have been generated during sonification.
At step 110 a photomask having the eventual desired aerogel pattern is placed in contact with the coated substrate. A patterned metal mask on silica (e.g. etched chrome photomask) as typically used in microelectronic manufacturing can be placed on top of the aerogel film, preferably with the metal side of the mask in contact with the aerogel film.
At step 112 the masked substrate is exposed to UV irradiation. The “masked” aerogel film is exposed to UV illumination of approximately 185 nm wavelength. The metal areas of the mask prevent UV light from impinging on the aerogel film and no ozone is created in the pores, while the clear areas of the mask allow UV light to impinge on the film and create ozone in the illuminated pores. The illuminated areas of the aerogel film form a pattern of hydrophilic material by removal of the organic modification on the internal pore surfaces which can be subsequently etched by aqueous reagents. If the UV exposure through the clear areas of the mask is not long enough the organic modification remains on the surface of the aerogel and the aerogel remains hydrophobic. The time of exposure can be adjusted to accommodate a film thickness and line width of interest, which in the present example was found to be approximately 5 minutes for a 1 um thick film having a line width of 0.25 mm and edge to edge spacing of 0.75 mm.
At step 114 the mask is removed from the substrate and the hydrophilic regions of the aerogel film are etched using a 1 molar sodium hydroxide (NaOH) solution. It was found that a glass etchant of 1 molar NaOH was able to remove the hydrophilic regions of the aerogel film and not leave a silica residue. Etching was performed at room temperature and in the present example, could be accomplished by dipping the coated substrate in the 1 molar NaOH solution, allowing the excess etchant to drain off, and etching for approximately a minute and a half.
At step 116 the substrate now having an etched and patterned aerogel film layer is rinsed and dried. In the exemplary embodiment, the patterned films were rinsed in de-ionized water and let to dry. It should be noted that the patterned hydrophobic areas remaining on the surface of the substrate are not prone to wetting by the de-ionized water and therefore will not collapse upon drying.
Optional step 118 can be employed in applications where it is desired to have a pattern of hydrophilic aerogel remaining on the surface of the substrate. As noted above, at step 116 a hydrophobic aerogel pattern is produced. Irradiating the hydrophobic aerogel pattern with UV will create ozone to remove the organic modification within the pore surfaces of the patterned aerogel. Step 118 can be performed with or without the use of a mask, as an application warrants.
The above described exemplary embodiments present several variants of the invention but do not limit the scope of the invention. Those skilled in the art will appreciate that the present invention can be implemented in other equivalent ways. The actual scope of the invention is intended to be defined in the following claims. | A method for producing a pattern in an aerogel disposed as a coating on a substrate comprises exposing the aerogel coating to the vapors of a hydrophobic silane compound, masking the aerogel coating with a shadow photomask and irradiating the aerogel coating with ultraviolet (UV) irradiation. The exposure to UV through the shadow mask creates a pattern of hydrophobic and hydrophilic regions in the aerogel coating. Etching away the hydrophilic regions of the aerogel coating, preferably with a 1 molar solution of sodium hydroxide, leaves the unwetted and unetched hydrophobic regions of the aerogel layer on the substrate, replicating the pattern of the photomask. The hydrophobic aerogel pattern can be further exposed to UV irradiation if desired, to create a hydrophilic aerogel pattern. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a new non-woven fabric material comprising hyaluronic acid derivatives, methods of production thereof, and methods of using said material in medical and pharmaceutical applications.
2. Description of Related Art
Hyaluronic acid is a natural heteropolysaccharide composed of alternating residues of D-glucuronic acid and N-acetyl-D-glucosamine. It is a linear polymer with a molecular weight of between 50,000 and 13,000,000 depending upon the source from which it is obtained, and the preparation and determination methods employed. It is present in nature in pericellular gels, in the fundamental substance of connective tissues of vertebrate organisms of which it is one of the main components, in the synovial fluid of joints, in the vitreous humor, in human umbilical cord tissues, and in cocks' combs.
There are known, specific fractions of hyaluronic acid with definite molecular weights that do not present inflammatory activity, and which can therefore be used to facilitate wound healing, to substitute for the endobulbar fluids, or which can be employed in therapy for joint pathologies by intra-articular injections, as described in European Patent No. 0 138 572 granted to Applicants on Jul. 25, 1990.
Also known are hyaluronic acid esters, wherein all or some of the carboxy groups of the acid are esterified, and their use in the pharmaceutical and cosmetic fields and in the area of biodegradable plastic materials, as described in U.S. Pat. Nos. 4,851,521 and 4,965,353 granted to Applicants.
Hyaluronic acid is known to play a fundamental role in tissue repair processes, especially in the first stages of granulation, by stabilizing the coagulation matrix and controlling its degradation, favoring the recruitment of inflammatory cells such as polymorphonuclear leukocytes and monocytes, of mesenchymal cells such as fibroblasts and endothelial cells, and in orienting the subsequent migration of epithelial cells.
It is known that the application of solutions of hyaluronic acid can accelerate healing in patients affected by bedsores, wounds and burns. The role of hyaluronic acid in the various phases that constitute tissue repair processes has been described, by the construction of a theoretical model, by Weigel P. H. et al.: "A model for the role of hyaluronic acid and fibrin in the early events during the inflammatory response and wound healing," J. Theor. Biol., 119: 219, 1986.
Studies aimed at obtaining manufactured products to apply to the skin, composed of hyaluronic acid esters as such or in mixtures with other polymers have led to the creation of various types of products. Among these are fabrics, such as gauzes of varying thickness (number of threads per centimeter), with varying dimensions, and with threads of varying denier (weight per 9000 meters of thread). Films of widely varying thickness have been proposed, as described in U.S. Pat. Nos. 4,851,521 and 4,965,353.
The use of such materials as skin coverings is limited by their stiffness, which is more or less determined according to how they were made. It is always a problem, however, when the material has to mould itself to the surface to be covered. Another drawback to the use of such materials is their poor absorbability, if any, of liquids such as solutions of disinfectants, antibiotics, antiseptics, antimicotics, proteins or wound healing substances in general, even when these are neither thick nor viscous.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide pliable non-woven fabric materials.
It is also an object of the present invention to provide a method for the preparation of such non-woven fabric materials.
The non-woven fabric materials of the present invention are composed of hyaluronic acid esters, used singly or in combination with one another, or with other types of polymers. Such materials are particularly soft, and can be easily impregnated with various kinds of liquids.
Further scope of the applicability of the present invention will become apparent from the detailed description and drawings provided below. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features, and advantages of the present invention will be better understood from the following detailed descriptions taken in conjunction with the accompanying drawings, all of which are given by way of illustration only, and are not limitative of the present invention, in which:
FIG. 1 is a schematic diagram illustrating the steps involved in the production of the non-woven fabric material of the present invention.
FIG. 2 shows the appearance of the non-woven fabric material comprising the benzyl ester of hyaluronic acid, HYAFF 11, produced in Example 27.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description of the invention is provided to aid those skilled in the art in practicing the present invention. Even so, the following detailed description should not be construed to unduly limit the present invention, as modifications and variations in the embodiments herein discussed may be made by those of ordinary skill in the art without departing from the spirit or scope of the present inventive discovery.
The contents of each of the references cited in the present application are herein incorporated by reference in their entirety.
The objects of the present invention are achieved by non-woven fabrics according to the present invention weighing between about 20 gr/mq and about 500 gr/mq, and between about 0.2 mm and about 5 mm in thickness. The non-woven fabric can be described as a web composed of a large quantity of fibers varying in diameter between about 12 and about 60 micrometers and in length between about 5 mm and about 100 mm, joined together by chemical coagulation or mechanical means, or with the aid of cohesive material.
The non-woven fabric comprises hyaluronic acid esters used singly or in mixtures with each other in varying ratios. Moreover, the present non-woven fabrics can comprise mixtures of fibers of hyaluronic acid esters with fibers of natural polymers, varying in ratio from 1 to 100% of the total, such as collagen, or coprecipitates of collagen and glycosaminoglycans, cellulose, polysaccharides in gel form such as chitin, chitosan, pectin or pectic acid, agar, agarose, xanthan gum, gellan, alginic acid or alginates, polymannan or polyglycans, starches, natural gums, or fibers obtained from semisynthetic derivatives of natural polymers such as collagen cross-linked with agents such as aldehydes or precursors of the same, dicarboxylic acids or halides of the same, diamines, derivatives of cellulose, alginic acid, starch, hyaluronic acid, chitin or chitosan, gellan, xanthan, pectin, or pectic acid, polyglycans, polymannan, agar, agarose, natural gums, glycosaminoglycans, or fibers obtained from synthetic polymers, such as polylactic acid, polyglycolic acid or copolymers of the same or their derivatives, polydioxanes, polyphosphazenes, polysulfone resins, and polyurethane resins.
The non-woven fabrics of the present invention possessing the above-mentioned characteristics can be produced from multifilaments produced by the usual wet and dry spinning methods and then cut into the desired lengths. The mass of fibers is fed into a carding machine which makes it into staples. The staples are then fed into a cross lapper, from which they emerge as webs of a specific weight.
The web can undergo chemical or mechanical cohesive treatment such as soaking in solvents and subsequent coagulation, needle punching treatment, treatment with bonding agents of the same material as constitutes the non-woven fabric, or of a different material, etc.
With respect to mechanical cohesive treatment, the principal of reinforcement of the fibrous web is based on the entangling of the fibers and the increased fiber friction obtained by the consolidation of the fibrous web. The fibers are entangled by piercing the web vertically with felting needles. These needles are mounted in machines, and the fibrous web is fed to the needling machine for needling, and finally to a structuring machine, which carries out the surface structuring.
With respect to treatments with bonding agents, chemical cohesive treatment with bonding agents is performed on the fibrous web when it emerges from the carding machine (FIG. 1, detail 9). The purpose of this treatment is to fix the fibers at their contact points. In the case of non-woven fabrics composed essentially of hyaluronic acid esters, this is achieved by spraying (11) the fibrous web emerging from the carding machine with a solution of hyaluronic acid esters in, for example, dimethylsulfoxide. The dimethylsulfoxide, being a solvent for the fibers comprising the web, dissolves them, and "fuses" them in the subsequent coagulation bath (12). The web thus fixed is then washed (13) and dried (14).
The coagulation baths 3 and 15 are stainless steel, and are in the form of an upturned triangle so that the extracted solubilization material being formed can be kept in contact with fresh coagulation solvent.
The coagulation process is essentially an extraction process by which, from a solution of polymer and solvent, the extraction of the solubilization solvent and the solidification of the polymer can be effected by the addition of a second solvent, for example ethanol, in which the solubilization solvent, for example dimethylsulfoxide, is soluble, and the polymer is insoluble.
The above-described treatments have the effect of fixing the fibers one to the other so as to produce a structure composed of haphazardly placed, matted fibers, constituting a soft, resistant material.
The present invention therefore relates to a new class of products, non-woven fabrics, to be used in the medical/pharmaceutical field as skin coverings. These fabric materials are totally or partially biocompatible and bioabsorbable, and are composed of hyaluronic acid esters used singly or in mixtures with each other, or with other natural or synthetic polymers. Such materials are characterized by their softness, and by their ability to absorb liquids.
Such non-woven fabrics can be impregnated with, among other things, solutions of antibiotics, antiseptics, antimicotics or proteins. The term "non-woven fabric" covers in practice materials such as webs and felts, etc., composed of a large quantity of fibers, chemically or mechanically stuck together. The material has the appearance of a fabric, even though it is not woven in the strict sense of the word.
For purely illustrative purposes, described hereafter are some examples of how the non-woven fabric material of the present invention can be produced.
THE ESTERS OF HYALURONIC ACID
Esters of hyaluronic acid useful in the present invention are esters of hyaluronic acid with aliphatic, araliphatic, cycloaliphatic or heterocyclic alcohols, in which are esterified all (so-called "total esters") or only a part (so-called "partial esters") of the carboxylic groups of the hyaluronic acid, and salts of the partial esters with metals or with organic bases, biocompatible or acceptable from a pharmacological point of view.
The useful esters include esters which derive from alcohols which themselves possess a notable pharmacological action. The saturated alcohols of the aliphatic series or simple alcohols of the cycloaliphatic series are useful in the present invention.
In the above mentioned esters in which some of the carboxylic acid groups remain free (i.e., partial esters), these may be salified with metals or organic bass, such as with alkaline or alkaline earth metals or with ammonia or nitrogenous organic bases.
Most of the esters of hyaluronic acid ("HY"), unlike HY itself, present a certain degree of solubility in organic solvents. This solubility depends on the percentage of esterified carboxylic groups and on the type of alkyl group linked with the carboxyl. Therefore, an HY compound with all its carboxylic groups esterified presents, at room temperature, good solubility for example in dimethylsulfoxide (the benzyl ester of HY dissolves in DMSO in a measure of 200 mg/ml). Most of the total esters of HY present also, unlike HY and especially its salts, poor solubility in water and are essentially insoluble in water. The solubility characteristics, together with particular and notable viscoelastic properties, make the HY esters particularly preferred for use in composite membranes.
Alcohols of the aliphatic series to be used as esterifying components of the carboxylic groups of hyaluronic acid for use in composite membranes according to the present invention are for example those with a maximum of 34 carbon atoms, which may be saturated or unsaturated and which may possibly also be substituted by other free functional or functionally modified groups, such as amine, hydroxyl, aldehyde, ketone, mercaptan, or carboxyl groups or by groups derived from these, such as hydrocarbyl or di-hydrocarbylamine groups (from now on the term "hydrocarbyl" will be used to refer not only to monovalent radicals of hydrocarbons such as the C n H 2n+1 type, but also bivalent or trivalent radicals, such as "alkylenes" C n H 2n-1 or "alkylidenes" C n H 2n ), ether or ester groups, acetal or ketal groups, thioether or thioester groups, and esterified carboxyl or carbamide groups and carbamide substituted by one or more hydrocarbyl groups, by nitrile groups or by halogens.
Of the above mentioned groups containing hydrocarbyl radicals, these are preferably lower aliphatic radicals, such as alkyls, with a maximum of 6 carbon atoms. Such alcohols may also be interrupted in the carbon atom chain by heteroatoms, such as oxygen, nitrogen and sulfur atoms. Preferred are alcohols substituted with one or two of the said functional groups.
Alcohols of the above mentioned group which are preferably used are those with a maximum of 12, and especially 6 carbon atoms, and in which the hydrocarbyl atoms in the above mentioned amine, ether, ester, thioether, thioester, acetal, ketal groups represent alkyl groups with a maximum of 4 carbon atoms, and also in the esterified carboxyl or substituted carbamide groups the hydrocarbyl groups are alkyls with the same number of carbon atoms, and in which in the amine or carbamide groups may be alkylenamine or alkylenecarbamide groups with a maximum of 8 carbon atoms. Of these alcohols, specifically preferred are saturated and nonsubstituted alcohols, such as the methyl, ethyl, propyl, and isopropyl alcohols, normal butyl alcohol, isobutyl alcohol, tertiary butyl alcohol, the amyl, pentyl, hexyl, octyl, nonyl and dodecyl alcohols and, above all, those with a linear chain, such as normal octyl and dodecyl alcohols. Of the substituted alcohols of this group, the bivalent alcohols are useful, such as ethyleneglycol, propyleneglycol and butyleneglycol, the trivalent alcohols such as glycerine, the aldehyde alcohols such as tartronic alcohol, the carboxylic alcohols such as lactic acids, for example glycolic acid, malic acid, the tartaric acids, citric acid, the aminoalcohols, such as normal aminoethanol, aminopropanol, normal aminobutanol and their dimethylated and diethylated derivatives in the amine function, choline, pyrrolidinylethanol, piperidinylethanol, piperazinylethanol and the corresponding derivatives of normal propyl or normal butyl alcohol, monothioethyleneglycol or its alkyl derivatives, such as the ethyl derivative in the mercaptan function.
Of the higher saturated aliphatic alcohols, preferred are cetyl alcohol and myricyl alcohol, but for the aim of the present invention the higher unsaturated alcohols with one or two double bonds, are especially important, such as especially those contained in many essential oils and related to terpenes, such as citronellol, geraniol, nerol, nerolidol, linalool, farnesol, and phytol. Of the unsaturated lower alcohols it is necessary to consider allyl alcohol and propargyl alcohol. Of the araliphatic alcohols, preferred are those with only one benzene residue and in which the aliphatic chain has a maximum of 4 carbon atoms, which the benzene residue can be substituted by between 1 and 3 methyl or hydroxyl groups or by halogen atoms, especially by chlorine, bromine and iodine, and in which the aliphatic chain may be substituted by one or more functions chosen from the group containing fee amine groups or mono- or dimethylated or by pyrrolidine or piperidine groups. Of these alcohols, most preferred are benzyl alcohol and phenetyl alcohol.
The alcohols of the cycloaliphatic or aliphatic-cycloaliphatic series may derive from mono- or polycyclic hydrocarbons, may preferably have a maximum of 34 carbon atoms, may be unsubstituted and may contain one or more substituents, such as those mentioned above for the aliphatic alcohols. Of the alcohols derived from cyclic monoannular hydrocarbons, preferred are those with a maximum of 12 carbon atoms, the rings with preferably between 5 and 7 carbon atoms, which may be substituted for example by between one and three lower alkyl groups, such as methyl, ethyl, propyl or isopropyl groups. As specific alcohols of this group the following are most preferred: cyclohexanol, cyclohexanediol, 1,2,3-cyclohexanetriol and 1,3,5-cyclohexanetriol (phloroglucitol), inositol, and the alcohols which derive from p-methane such as carvomenthol, menthol, and α-γterpineol, 1-terpineol, 4-terpineol and piperitol, or the mixture of these alcohols known as "terpineol", 1,4- and 1,8 terpin. Of alcohols which derive from hydrocarbons with condensed rings, such as those of the thujane, pinane or comphane, the following are preferred: thujanol, sabinol, pinol hydrate, D and L-borneol and D and L-isoborneol.
Aliphatic-cycloaliphatic polycyclic alcohols to be used for the esters of the present invention are sterols, cholic acids and steroids, such as sexual hormones and their synthetic analogues, especially corticosteroids and their derivatives. It is therefore possible to use: cholesterol, dihydrocholesterol, epidihydrocholesterol, coprostanol, epicoprostanol, sitosterol, stigmasterol, ergosterol, cholic acid, deoxycholic acid, lithocholic acid, estriol, estradiol, equilenin, equilin and their alkylate derivatives, as well as their ethynyl or propynyl derivatives in position 17, such as 17α-ethynl-estradiol or 7α-methyl-17α-ethynyl-estradiol, pregnenolone, pregnanediol, testosterone and its derivatives, such as 17α-methyltestosterone, 1,2-dehydrotestosterone and 17α-methyl-1,2-dehydrotesterone, the alkynylate derivatives in position 17 of testosterone and 1,2-dehydrotestosterone, such as 17α-ethynyltestosterone, 17α-propynyltestosterone, norgestrel, hydroxyprogesterone, corticosterone, deoxycorticosterone, 19-nortestosterone, 19-nor-17α-methyltestosterone and 19-nor-17α-ethynyltestosterone, antihormones such as cyproterone, cortisone, hydrocortisone, prednisone, prednisolone, fluorocortisone, dexamethasone, betamethasone, paramethasone, flumethasone, fluocinolone, fluprednylidene, clobetasol, beclomethasone, aldosterone, deoxycorticosterone, alfaxolone, alfadolone, and bolasterone. As esterifying components for the esters of the present invention the following are useful: genins (aglycones) of the cardioactive glucosides, such as digitoxigenin, gitoxigenin, digoxigenin, strophanthidin, tigogenin and saponins.
Other alcohols to be used according to the invention are vitamins, such as axerophthol, vitamins D 2 and D 3 , aneurine, lactoflavine, ascorbic acid, riboflavine, thiamine, and pantothenic acid.
Of the heterocyclic acids, the following can be considered as derivatives of the above mentioned cycloaliphatic or aliphatic-cycloaliphatic alcohols if their linear or cyclic chains are interrupted by one or more, for example by between one and three heteroatoms, for instance chosen from the group formed by --O--, --S--, --N, and --NH--, and in these, there may be one or more unsaturated bonds, for example double bonds, in particular between one and three, thus including also heterocyclic compounds with aromatic structures. For example the following should be mentioned: furfuryl alcohol, alkaloids and derivatives such as atropine, scopolamine, cinchonine, la cinchonidine, quinine, morphine, codeine, nalorphine, N-butylscopolammonium bromide, ajmaline; phenylethylamines such as ephedrine, isoproterenol, epinephrine; phenothiazine drugs such as perphenazine, pipothiazine, carphenazine, homofenazine, a cetophenazine, fluophenazine, and N-hydroxyethylpromethazine chloride; thioxanthene drugs such as flupenthixol and clopenthixol; anticonvulsants such as meprophendiol; antipsychotics such as opipramol; antiemetics such as oxypendyl; analgesics such as carbetidine and phenoperidine and methadol; hypnotics such as etodroxizine; anorexics such as benzidrol and diphemethoxidine; minor tranquilizers such as hydroxyzine; muscle relaxants such as cinnamedrine, diphylline, mephenesin, methocarbamol, chlorphenesin, 2,2-diethyl-1,3-propanediol, guaifenesin, hydrocilamide; coronary vasodilators such as dipyridamole and oxyfedrine; adrenergic blockers such as propanolol, timolol, pindolol, bupranolol, atenolol, metroprolol, practolol; antineoplastics such as 6-azauridine, cytarabine, floxuridine; antibiotics such as chloramphenicol, thiamphenicol, erythromycin, oleandomycin, lincomycin; antivirals such as idoxuridine; peripheral vasodilators such as isonicotinyl alcohol; carbonic anhydrase inhibitors such as sulocarbilate; antiasthmatics and antiinflammatories such as tiaramide; sulfamidics such as 2-p-sulfanilonoethanol.
In some cases hyaluronic acid esters may be of interest where the ester groups derive from two or more therapeutically active hydroxylic substances, and naturally all possible variants may be obtained. Especially interesting are the substances in which two types of different ester groups deriving from drugs of a hydroxylic character are present and in which the remaining carboxyl groups are free, salified with metals or with a base, possibly also the bases being themselves therapeutically active, for example with the same or similar activity as that of the esterifying component. In particular, it is possible to have hyaluronic esters deriving on the one hand from an antiinflammatory steroid, such as one of those mentioned previously, and on the other hand from a vitamin, from an alkaloid or from an antibiotic, such as one of those listed.
METHOD OF PREPARING HY ESTERS OF THE INVENTION
Method A
The esters of hyaluronic acid may be prepared by methods known per se for the esterification of carboxylic acids, for example by treatment of free hyaluronic acid with the desired alcohols in the presence of catalyzing substances, such as strong inorganic acids or ionic exchangers of the acid type, or with an etherifying agent capable of introducing the desired alcoholic residue in the presence of inorganic or organic bases. As esterifying agents it is possible to use those known in literature, such as especially the esters of various inorganic acids or of organic sulphonic acids, such as hydracids, that is hydrocarbyl halogenides, such as methyl or ethyl iodide, or neutral sulphates or hydrocarbyl acids, alfites, carbonates, silicates, phosphites or hydrocarbyl sulfonates, such as methyl benzene or p-toluene-sulfonate or methyl or ethyl chlorosulfonate. The reaction may take place in a suitable solvent, for example an alcohol, preferably that corresponding to the alkyl group to be introduced in the carboxyl group. But the reaction may also take place in non-polar solvents, such as ketones, ethers, such as dioxane or aprotic solvents, such as dimethylsulphoxide. As a base it is possible to use for example a hydrate of an alkaline or alkaline earth metal or magnesium or silver oxide or a basic salt or one of these metals, such as a carbonate, and, of the organic bases, a tertiary azotized base, such as pyridine or collidine. In the place of the base it is also possible to use an ionic exchanger of the basic type.
Another esterification method employs the metal salts or salts with organic azotized bases, for example ammonium or ammonium substitute salts. Preferably, the salts of the alkaline or alkaline earth metals are used, but also any other metallic salt may be used. The esterifying agents are also in this case those mentioned above and the same applies to the solvents. It is preferable to use aprotic solvents, for example dimethylsulphoxide and dimethylformamide.
In the esters obtained according to this procedure or according to the other procedure described hereafter, free carboxylic groups of the partial esters may be salified, if desired, in a per se known manner.
Method B
The hyaluronic esters may also be prepared by a method which consists of treating a quaternary ammonium salt of hyaluronic acid with an etherifying agent, preferably in an aprotic organic solvent.
As organic solvents it is preferable to use aprotic solvents, such as dialkylsulphoxides, dialkylcarboxamides, such as in particular lower alkyl dialkylsulphoxides, especially dimethyl-sulphoxide, and lower alkyl dialkylamides of lower aliphatic acids, such as dimethyl or diethyl-formamide or dimethyl or diethylacetamide.
Other solvents however are to be considered which are not always aprotic, such as alcohols, ethers, ketones, esters, especially aliphatic or heterocyclic alcohols and ketones with a lower boiling point, such as hexafluoroisopropanol, trifluoroethanol, and N-methylpyrrolidone.
The reaction is effected preferably at a temperature range of between about 0° C. and 100° C., especially between about 25° C. and 75° C., for example at about 30° C.
The esterification is carried out preferably by adding by degrees the esterifying agent to the above mentioned ammonium salt to one of the above mentioned solvents, for example to dimethyl-sulphoxide.
As an alkylating agent it is possible to use those mentioned above, especially the hydrocarbyl halogens, for example alkyl halogens. As starting quaternary ammonium salts it is preferable to use the lower ammonium tetraalkylates, with alkyl groups preferably between 1 and 6 carbon atoms. Mostly, hyaluronate of tetrabutylammonium is used. It is possible to prepare these quaternary ammonium salts by reacting a metallic salt of hyaluronic acid, preferably one of those mentioned above, especially sodium or potassium salt, in aqueous solution with a salified sulphonic resin with a quaternary ammonium base.
One variation of the previously described procedure consists in reacting a potassium or sodium salt of hyaluronic acid, suspended in a suitable solution such as dimethylsulphoxide, with a suitable alkylating agent in the presence of catalytic quantities of a quaternary ammonium salt, such as iodide of tetrabutylammonium.
For the preparation of the hyaluronic acid esters, it is possible to use hyaluronic acids of any origin, such as for example the acids; extracted from the above mentioned natural starting materials, for example from cocks' combs. The preparation of such acids is described in literature: preferably, purified hyaluronic acids are used. Especially used are hyaluronic acids comprising molecular fractions of the integral acids obtained directly by extraction of the organic materials with molecular weights varying within a wide range, for example from about 90%-80% (MW=11.7-10.4 million) to 0.2% (MW=30,000) of the molecular weight of the integral acid having a molecular weight of 13 million, preferably between 5% and 0.2%. Such fractions may be obtained with various procedures described in literature, such as by hydrolyzing, oxydizing, enzymatic or physical procedures, such as mechanical or radiational procedures. Primordial extracts are therefore often formed during these same by publication procedures (for example see the article by Balazs et al. quoted above in "Cosmetics & Toiletries"). The separation and purification of the molecular fractions obtained are brought about by known techniques, for example by molecular filtration.
Additionally useful are purified fractions obtainable from hyaluronic acid, such as for example the ones described in European Patent Publn. No. 0138572.
The salification of HY with the above metals, for the preparation of starting salts for the particular esterification procedure described above, is performed in a per se known manner, for example by reacting HY with the calculated base quantity, for example with alkaline hydrates or with basic salts of such metals, such as carbonates or bicarbonates.
In the partial esters it is possible to salify all the remaining carboxylic groups or only part of them, dosing the base quantities so as to obtain the desired stoichiometric degree of salification. With the correct degree of salification it is possible to obtain esters with a wide range of different dissociation constants and which therefore give the desired pH, in solution or "in situ" at the time of therapeutic application.
PREPARATION EXAMPLES
The following exemplify the preparation of hyaluronic acid esters useful in the composite membranes of the present invention.
EXAMPLE 1
Preparation of the (Partial) Propyl Ester of Hyaluronic Acid (HY)--50% of the Esterified Carboxylic Groups--50% of the Salified Carboxylic Groups (Na)
12.4 g of HY tetrabutylammonium salt with a molecular weight 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 1.8 g (10.6 m.Eq.) of propyl iodide are added and the resulting solution is kept at a temperature of 30° for 12 hours.
A solution containing 62 ml of water and 9 g of sodium chloride is added and the resulting mixture is slowly poured into 3,500 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed three times with 500 ml of acetone/water 5:1 and three times with acetone and finally vacuum dried for eight hours at 30° C.
The product is then dissolved in 550 ml of water containing 1% of sodium chloride and the solution is slowly poured into 3,000 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed twice with 500 ml of acetone/water (5:1) and three times with 500 ml of acetone and finally vacuum dried for 24 hours at 30° C. 7.9 g of the partial propyl ester compound in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030, (1961)].
EXAMPLE 2
Preparation of the (Partial) Isopropyl Ester of Hyaluronic Acid (HY)--50% of Esterified Carboxylic Groups--50% of Salified Carboxylic Groups (Na)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 160,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 1.8 g (10.6 m.Eq.) of isopropyl iodide are added and the resulting solution is kept for 12 hours at 30° C.
A solution containing 62 ml of water and 9 g of sodium chloride is added and the resulting mixture is slowly poured into 3,500 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed three times with 500 ml of acetone/water 5:1 and three times with acetone and finally vacuum dried for eight hours at 30° C.
The product is then dissolved in 550 ml of water containing 1% of sodium chloride and the solution is slowly poured into 3,000 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed twice with 500 ml of acetone/water 5:1 and three times with 500 ml of acetone and finally vacuum dried for 24 hours at 30° C. 7.8 g of the partial isopropyl ester compound in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 3
Preparation of the (Partial) Ethyl Ester of Hyaluronic Acid (HY)--75% of Esterified Carboxylic Groups--25% of Salified Carboxylic Groups (Na)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 250,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 2.5 g (15.9 m.Eq.) of ethyl iodide are added and the resulting solution is kept for 12 hours at 30° C.
A solution containing 62 ml of water and 9 g of sodium chloride is added and the resulting mixture is slowly poured into 3,500 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed three times with 500 ml of acetone/water 5:1 and three times with acetone and finally vacuum dried for eight hours at 30° C.
The product is then dissolved in 550 ml of water containing 1% of sodium chloride and the solution is slowly poured into 3,000 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed twice with 500 ml of acetone/water 5:1 and three times with 500 ml of acetone and finally vacuum dried for 24 hours at 30° C. 7.9 g of the partial ethyl ester compound in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030, (1961)].
EXAMPLE 4
Preparation of the (Partial) Methyl Ester of Hyaluronic Acid (HY)--75% of Esterified Carboxylic Groups--25% of Salified Carboxylic Groups (Na)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 80,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 2.26 g (15.9 m.Eq.) of methyl iodide are added and the resulting solution is kept for 12 hours at 30° C.
A solution containing 62 ml of water and 9 g of sodium chloride is added and the resulting mixture is slowly poured into 3,500 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed three times with 500 ml of acetone/water 5:1 and three times with acetone and finally vacuum dried for eight hours at 30° C.
The product is then dissolved in 550 ml of water containing 1% of sodium chloride and the solution is slowly poured into 3,000 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed twice with 500 ml of acetone/water 5:1 and three times with 500 ml of acetone and finally vacuum dried for 24 hours at 30° C. 7.8 g of the partial methyl ester compound in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 5
Preparation of the Methyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 120,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 3 g (21.2 m.Eq.) of methyl iodide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for twenty four hours at 30° C.
8 g of the ethyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 6
Preparation of the Ethyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 85,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 3.3 g (21.2 m.Eq.) of ethyl iodide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for twenty-four hours at 30° C.
8 g of the ethyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 7
Preparation of the Propyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 3.6 g (21.2 m.Eq.) of propyl iodide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for twenty-four hours at 30° C.
8.3 g of the propyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 8
Preparation of the (Partial) Butyl Ester of Hyaluronic Acid (HY)--50% of Esterified Carboxylic Groups--50% of Salified Carboxylic Groups (Na)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 620,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 1.95 g (10.6 m.Eq.) of n-butyl iodide are added and the resulting solution is kept for 12 hours at 30° C.
A solution containing 62 ml of water and 9 g of sodium chloride is added and the resulting mixture is slowly poured into 3,500 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed three times with 500 ml of acetone/water 5:1 and three times with acetone and finally vacuum dried for eight hours at 30° C.
The product is then dissolved in 550 ml of water containing 1% of sodium chloride and the solution is slowly poured into 3,000 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed twice with 500 ml of acetone/water 5:1 and three times with 500 ml of acetone and finally vacuum dried for 24 hours at 30° C. 8 g of the partial butyl ester compound in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 9
Preparation of the (Partial) Ethoxycarbonylmethyl Ester of Hyaluronic Acid (HY)--75% of Esterified Carboxylic Groups--25% of Salified Carboxylic Groups (Na)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 180,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 2 g of tetrabutylammonium iodide and 1.84 g (15 m.Eq.) of ethyl chloroacetate are added and the resulting solution of kept for 24 hours at 30° C.
A solution containing 62 ml of water and 9 g of sodium chloride is added and the resulting mixture is slowly poured into 3,500 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed three times with 500 ml of acetone/water 5:1 and three times with acetone and finally vacuum dried for eight hours at 30° C.
The product is then dissolved in 550 ml of water containing 1% of sodium chloride and the solution is slowly poured into 3,000 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed twice with 500 ml of acetone/water 5:1 and three times with 500 ml of acetone and finally vacuum dried for 24 hours at 30° C. 10 g of the partial ethoxycarbonyl methyl ester compound in the title are obtained.
Quantitative determination of the ethoxylic ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 10
Preparation of the N-Pentyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 620,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 3.8 g (25 m.Eq.) of n-pentyl bromide and 0.2 g of iodide tetrabutyl-ammonium are added, the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for twenty four hours at 30° C.
8.7 g of the n-pentyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described on pages 169-172 of Siggia S. and Hann J. G. "Quantitative organic analysis via functional groups" 4th Edition, John Wiley and Sons.
EXAMPLE 11
Preparation of the Isopentyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethysulfoxide at 25° C., 3.8 g (25 m.Eq.) of isopentyl bromide and 0.2 g of tetrabutylammonium iodide are added, the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for twenty four hours at 30° C.
8.6 g of the isopentyl ester product featured in the title are obtained. Quantitative determination of the ester groups is carried out according to the method described on pages 169-172 of Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups" 4th Edition, John Wiley and Sons.
EXAMPLE 12
Preparation of the Benzylester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.5 g (25 m.Eq.) of benzyl bromide and 0.2 g of tetrabutylammonium iodide are added, the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for twenty four hours at 30° C.
9 g of the benzyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out according to the method described on pages 169-172 of Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups" 4th Edition, John Wiley and Sons.
EXAMPLE 13
Preparation of the β-Phenylethyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 125,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.6 g (25 m.Eq.) of 2-bromoethylbenzene and 185 mg of tetrabutylammonium iodide are added, and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is thus formed which is then filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for twenty four hours at 30° C.
9.1 g of the β-phenylethyl ester in the title are obtained. Quantitative determination of the ester groups is carried out according to the method described on page 168-172 of Siggia S., and hanna J. G. "Quantitative organic analysis via functional groups" 4th Edition, John Wiley and Sons.
EXAMPLE 14
Preparation of the Benzyl Ester of Hyaluronic Acid (HY)
3 g of the potassium salt of HY with a molecular weight of 162,000 are suspended in 200 ml of dimethylsulfoxide; 120 mg of tetrabutylammonium iodide and 2.4 g of benzyl bromide are added.
The suspension is kept in agitation for 48 hours at 30° C. The resulting mixture is slowly poured into 1,000 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 150 ml of ethyl acetate and finally vacuum dried for twenty four hours at 30° C.
3.1 g of the benzyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out according to the method described on pages 169-172 of Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups" 4th Edition, John Wiley and Sons.
EXAMPLE 15
Preparation of the (Partial Propyl) Ester of Hyaluronic Acid (HY)--85% of Esterified Carboxylic Groups--15% of Salified Carboxylic Groups (Na)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 165,1000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethysulfoxide at 25° C., 2.9 g (17 m.Eq.) of propyl iodide are added and the resulting solution is kept for 12 hours at 30° C.
A solution is then added containing 62 ml of water and 9 g of sodium chloride and the resulting mixture is slowly poured into 3,500 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed three times with 500 ml of acetone/water 5:1 and three times with acetone and finally vacuum dried for eight hours at 30° C.
The product is then dissolved in 550 ml of water containing 1.% of sodium chloride and the solution is slowly poured into 3,000 ml of acetone under constant agitation. A precipitate is formed which is filtered and washed twice with 500 ml of acetone/water 5:1 and three times with 500 ml of acetone and finally vacuum dried for 24 hours at 30° C. 8 g of the partial propyl ester compound in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas [Anal. Chem. 33, 1028-1030 (1961)].
EXAMPLE 16
Preparation of the N-Octyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.1 g (21.2 m.Eq.) of 1-bromooctane are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 9.3 g of the octyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 17
Preparation of the Isopropyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170.000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 2.6 g (21.2 m.Eq.) of isopropyl bromide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 8.3 g of the isopropyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method of R. H. Cundiff and P. C. Markunas (Anal. Chem. 33, 1028-1030, 1961).
EXAMPLE 18
Preparation of the 2,6-Dichlorobenzyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170.000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 5.08 g (21.2 m.Eq.) of 2,6-dichlorobenzyl bromide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 9.7 g of the 2,6-dichlorobenzyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 19
Preparation of the 4-Terbutylbenzyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.81 g (21.2 m.Eq.) of 4-terbutylbenzyl bromide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 9.8 g of the 4-terbutylbenzyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups" 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 20
Preparation of the Heptadecyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 6.8 g (21.2 M.Eq.) of Heptadecyl bromide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 11 g of the Heptadecyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 21
Preparation of the Octadecyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 7.1 g (21.2 m.Eq.) of octadecyl bromide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 11 g of the octadecyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 22
Preparation of the 3-Phenylpropyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.22 g (21.2 m.Eq.) of 3-phenylpropyl bromide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 9 g of the 3-phenylpropyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 23
Preparation of the 3,4,5-Trimethoxy-Benzyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 M.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.6 g (21.2 m.Eq.) of 3,4,5-trimethoxybenzyl chloride are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 10 g of the 3,4,5-trimethoxybenzyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 24
Preparation of the Cinnamyl Ester of Hyaluronic Acid (HY)
12.4 g of Hy tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.2 9 (21.2 m.Eq.) of Cinnamyl bromide are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 9.3 g of the Cinnamyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 25
Preparation of the Decyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.7 g (21.2 m.Eq.) of 1-bromo decane are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 9.5 g of the Decyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
EXAMPLE 26
Preparation of the Nonyl Ester of Hyaluronic Acid (HY)
12.4 g of HY tetrabutylammonium salt with a molecular weight of 170,000 corresponding to 20 m.Eq. of a monomeric unit are solubilized in 620 ml of dimethylsulfoxide at 25° C., 4.4 g (21.2 m.Eq.) of 1-bromo nonane are added and the solution is kept for 12 hours at 30° C.
The resulting mixture is slowly poured into 3,500 ml of ethyl acetate under constant agitation. A precipitate is formed which is filtered and washed four times with 500 ml of ethyl acetate and finally vacuum dried for 24 hours at 30° C. 9 g of the Nonyl ester product in the title are obtained. Quantitative determination of the ester groups is carried out using the method described in Siggia S. and Hanna J. G. "Quantitative organic analysis via functional groups", 4th Edition, John Wiley and Sons, pages 169-172.
THE ESTERS OF ALGINIC ACID
The alginic acid esters which can be employed in the present invention can be prepared as described in EPA 0 251 905 A2 by starting with quaternary ammonium salts of alginic acid with an etherifying agent in a preferably aprotic organic solvent, such as dialkylsulfoxides, dialkylcarboxamides, such as in particular lower alkyl dialkylsulfoxides, above all dimethylsulfoxide, and lower alkyl dialkylamides of lower aliphatic acids, such as dimethyl or diethyl formamide or dimethyl or diethyl acetamide. It is possible, however, to use other solvents which are not always aprotic, such as alcohols, ethers, detones, esters, especially aliphatic or heterocyclic alcohols and ketones with a low boiling point, such as hexafluoroisopropanol and trifluoroethanol. The reaction is brought about preferably at a temperature of between about 0° and 100° C., and especially between about 25° and 75° C., for example at about 30° C.
Esterification is carried out preferably by gradually adding the esterifying agent to the above-mentioned ammonium salt dissolved in one of the solvents mentioned, for example in dimethylsulfoxide. As alkylating agents, those mentioned above can be used, especially hydrocarbyl halides, for example alkyl halides.
The preferred esterification process, therefore, comprises reacting, in an organic solvent, a quaternary ammonium salt of alginic acid with a stoichiometric quantity of a compound of the formula
A--X
wherein A is selected from the group consisting of an aliphatic, araliphatic, cycloaliphatic, aliphatic-cycloaliphatic and heterocyclic radicals, and X is a halogen atom, and wherein said stoichiometric quantity of A--X is determined by the degree of esterification desired.
As starting quaternary ammonium salts, it is preferable to use lower ammonium tetraalkylates, the alkyl groups having preferably between 1 and 6 carbon atoms. Mostly, the alginate of tetrabutylammonium is used. These quaternary ammonium salts can be prepared by reacting a metal salt of alginic acid, preferably one of those mentioned above, especially the sodium or potassium salt, in aqueous solution with a sulfonic resin salified with the quaternary ammonium base.
One variation of the previously specified procedure consists of reacting a potassium or sodium salt of alginic acid, suspended in a suitable solution such as dimethylsulfoxide, with a suitable alkylating agent in the presence of a catalyzing quantity of a quaternary ammonium salt, such as tetrabutylammonium iodide. This procedure makes it possible to obtain the total esters of alginic acid.
To prepare new esters it is possible to use alginic acids of any origin. The preparation of these acids is described in literature. It is preferable to use purified alginic acids.
In the partial esters, it is possible to salify all the remaining carboxy groups or only part of these, dosing the base quantity so as to obtain the desired stoichiometric degree of salification. By correctly gauging the degree of salification, it is possible to obtain esters with a wide range of different dissociation constants, thereby giving the desired pH in solutions or "in situ" at the time of therapeutic application.
ALAFF 11, the benzyl ester of alginic acid, and ALAFF 7, the ethyl ester of alginic acid, are particularly useful in the present composite membranes.
EXAMPLE 27
A non-woven fabric comprising hyaluronic acid benzyl ester HYAFF 11, weighing 40 gr/mq, 0.5 mm thick, was produced by the following procedure (see FIG. 1).
A solution of HYAFF 11 in dimethylsulfoxide at a concentration of 135 mg/ml is prepared in a tank (1) and fed by a gear metering pump (2) into a spinneret for wet extrusion composed of 3000 holes each measuring 65 microns.
The extruded mass of threads passes into a coagulation bath (3) containing absolute ethanol. It is then moved over transporting rollers into two successive rinsing baths (4 and 5) containing absolute ethanol. The drafting ratio of the first roller is set at zero while the drafting ratio between the other rollers is set at 1.05. Once it has been passed through the rinsing baths, the hank of threads is blown dry with hot air at 45°-50° C. (6) and cut with a roller cutter (7) into 40 mm fibers.
The mass of fibers thus obtained is tipped into a chute leading to a carding/cross lapping machine (9) from which it emerges as a web, 1 mm thick and weighing 40 mg/mq. The web is then sprayed with a solution of HYAFF 11 in dimethylsulfoxide at 80 mg/ml (11), placed in an ethanol coagulation bath (12), in a rinsing chamber (13), and lastly in a drying chamber (14).
The final thickness of the material is 0.5 mm. Its appearance can be seen in FIG. 2.
EXAMPLE 28
A non-woven fabric comprising the ethyl ester of hyaluronic acid, HYAFF 7, weighing 200 gr/mq and 1.5 mm thick, was produced by the following procedure.
Fibers of HYAFF 7, 3 mm long, obtained by the spinning process described in Example 27, were fed through a chute into a carding machine, from which they emerged as a 1.8 mm thick web weighing 200 gr/mq. The web is passed through a needle punching machine (FIG. 1, details 16, 17, and 18), which transforms it into a non-woven fabric weighing 200 gr/mq, and 1.5 mm thick.
EXAMPLE 29
A non-woven fabric weighing 200 gr/mq and 1.5 mm thick comprising a mixture of the ethyl ester of hyaluronic acid, HYAFF 7, and of hyaluronic acid benzyl ester, HYAFF 11, in equal quantities, was obtained by the following procedure.
Fibers of HYAFF 7 and HYAFF 11, measuring 3 mm in length, obtained by the spinning process described in Example 27 were thoroughly mixed in a spiral mixer. The mixture of fibers was fed into a carding machine from which it emerged as a 1.8 mm thick web weighing 200 gr/mq.
The web was put through a needle punching machine (FIG. 1, details 16, 17, and 18), which transformed it into a 1.5 mm thick unwoven fabric weighing 200 gr/mq, with the two materials perfectly mixed together.
EXAMPLE 30
A non-woven fabric weighing 40 gr/mq and 0.5 mm thick comprising a mixture of hyaluronic acid benzyl ester, HYAFF 11, and a partial (75%) benzyl ester of hyaluronic acid, HYAFF 11p75, in equal percentages, was produced by the following procedure.
HYAFF 11p75 is prepared as follows. 10 g of hyaluronic acid tetrabutylammonium salt, mw=620.76, equal to 16.1 nmole, are solubilized in a mixture of N-methyl pyrrolidone/H 2 O, 90/10, 2.5% in weight, to obtain 400 mls of solution. The solution is cooled to 10° C., then purified N 2 is bubbled through it for 30 minutes. This is then esterified with 1.49 ml (equal to 12.54 mmole) of benzyl bromide. The solution is gently shaken for 60 hours at 15°-20° C.
Subsequent purification is achieved by precipitation in ethyl acetate following the addition of a saturated solution of sodium chloride, and subsequent washings with a mixture of ethyl acetate/absolute ethanol, 80/20. The solid phase is separated by filtration, and treated with anhydrous acetone. 6.8 g of product are thus obtained, equal to a yield of about 95%.
Fibers of HYAFF 11 and HYAFF 11p75, 40 mm long, obtained by the process described in Example 1, were thoroughly mixed in a spiral mixer.
The mixed fibers were fed into a carding machine from which they emerged as a 1 mm thick web weighing 40 mg/mq. The web was then sprayed with a solution of HYAFF 11 in dimethylsulfoxide at 80 mg/ml (FIG. 1, detail 11), placed in an ethanol coagulation bath (12), then in a rinsing chamber (13) containing water or a mixture of water and ethanol in a ratio of from 10 to 95% ethanol, and finally in a drying chamber (14).
The material has a final thickness of 0.5 mm, and the fibers of HYAFF 11 and HYAFF 11p75 are perfectly mixed and adhered together.
EXAMPLE 31
A non-woven fabric comprising the benzyl ester of hyaluronic acid, HYAFF 11, weighing 200 gr/mq and 1.5 mm thick, impregnated with vancomycin, was produced by the following procedure.
The non-woven fabric obtained as described in Example 28 was immersed for 4 hrs in an aqueous solution of vancomycin at a concentration of 0.1 mg/ml. Subsequently, after treatment in a heated colander, the non-woven fabric is dried for 2 hrs in an oven. In vitro release tests showed that the vancomycin is contained in the material in pharmacologically active quantities.
The non-woven fabrics of the present invention can be advantageously utilized in various types of microsurgical procedures, such as in odontology, stomatology, otorhinolaryngology, orthopedics, neurosurgery, etc., in which it is necessary to employ a substance that can be metabolized by the organism and which is capable of facilitating flap take, reepithelialization of mucous membranes, stabilization of grafts, and the filling of cavities. The new nonwoven fabrics can also be employed as buffer media in surgery to the nose and inner ear.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | Biomaterials are disclosed comprised of biodegradable, biocompatible, and bioabsorbable nonwoven fabric materials for use in surgery for the guided regeneration of tissues. The non-woven fabric materials are comprised of threads embedded in a matrix, wherein both the matrix and the threads can be comprised of esters of hyaluronic acid, used singly or in combination, or esters of hyaluronic acid in combination with esters of alginic acid or other polymers. | 3 |
FIELD
[0001] The present application relates to lost circulation materials and, more particularly, to methods and systems for delivering a quantity of lost circulation materials.
BACKGROUND
[0002] Drilling wells to recover oil and gas typically requires introducing a drilling fluid into the well bore and recirculating the drilling fluid up and out of the well bore to lubricate the drilling components, such as the drill string and drill bit, and to maintain the integrity of the well bore during operation of the drill. As the drilling fluid is recirculated up the well bore, the fluid acts as a sealant to keep the walls of the well bore in place, which, among other things, allows the drill pipe to be raised or lowered without obstruction and facilitates removal of drilled material from the well bore.
[0003] Lost circulation materials, such as cottonseed hulls, cedar fiber, paper, cottonseed burrs, sawdust, cellophane, calcium carbonate and phenolic plastic, are used as additives in the drilling fluid to fill fissures, porous or fractured formations, or other undesirable subterranean characteristics existing or formed in the side walls of the well bore. Filling the voids in the well bore wall with lost circulation material helps to prevent the recirculating drilling fluid from filling the voids, losing drilling fluid, and ultimately preventing efficient circulation of the fluid and removal of debris from the well, or even complete cessation of the drilling process.
[0004] Transporting or delivering lost circulation materials in bulk from a source to the drilling fluid for mixing with the fluid prior to pumping the fluid into the well can be difficult. A known method includes manually unloading large sacks of hulls, e.g., 100-pound sacks, from a transportation vehicle and manually pouring the contents of the sacks into a hopper on top of a mud pit or drilling well for mixing with the drilling fluid. This method, however, can be undesirably inefficient and labor intensive.
[0005] In another known method, the lost circulation materials are drawn from a source by a pump, pumped through the pump, discharged out of the pump and through an exhaust, and introduced into the drilling fluid. One known drawback with this method is that the lost circulation materials being pumped through the pump can damage, or otherwise disrupt the performance of, the pump by contacting the pump's moving parts or lodging in portions of the pump resulting in congestion and backup of lost circulation material flow.
[0006] Therefore, it would be advantageous to develop methods and systems for delivering lost circulation material, including cottonseed hulls that overcome the drawbacks of known systems.
SUMMARY
[0007] Described herein are embodiments directed to a lost circulation material delivery systems and methods capable of moving cottonseed hulls or similar particulate material from a storage source, such as a storage bin or a bulk bag, into a mud pit of an oil or gas drilling well without having to convey the material through a driving device, such as a fan, blower or pump. In some embodiments, the lost circulation material is conveyed into the mud pit through a delivery conduit, such as by air or by an auger-type conveyer.
[0008] According to one exemplary embodiment, a method of delivering lost circulation material from a bulk source to a drilling well mud system for controlling lost circulation within the bore includes positioning a bulk container of lost circulation material at a location in the vicinity of but removed from drilling well bore. Lost circulation material is introduced from the bulk container into a sorting mechanism. The method further includes conveying the lost circulation material with a moving device from the sorting mechanism to the drilling well mud system along a path separated from the moving device.
[0009] In some implementations the path can include a conduit. In specific implementations, the method can further include creating pneumatic pressure within the conduit to create a stream of pressurized air directed toward the drilling well mud system and feeding the lost circulation material from the sorting mechanism into the stream of pressurized air.
[0010] In some implementations, the path is free of mechanical obstructions.
[0011] In certain implementations, the bulk container can include a bulk bag and introducing lost circulation material can include gravitationally feeding the material from the bag into the sorting mechanism.
[0012] In other implementations, a conduit can be in receiving communication with the bulk container of lost circulation material and expelling communication with the sorting mechanism. Further, in some implementations, introducing lost circulation material from the bulk container into the sorting mechanism can include creating a negative air pressure within the conduit to draw lost circulation material through the conduit.
[0013] According to another exemplary embodiment, a method of delivering cottonseed hulls from a bulk source to a drilling well mud system a for controlling lost circulation within the bore can include positioning a bulk container of cottonseed hulls at a location in the vicinity of but removed from the drilling well mud system. The method can further include providing a passageway extending from a source of pneumatic pressure to the drilling well bore and creating pneumatic pressure within the passageway to create a stream of pressurized air from the source of pneumatic pressure to the drilling well bore. The cottonseed hulls can be fed into the stream of pressurized air within the conduit downstream of the source of pressurized air to intermix the hulls with the air. The method can also include conveying the hulls through the passageway to the drilling well mud system.
[0014] In some implementations, the cottonseed hulls can be fed into the air stream at a substantially constant rate of delivery. In other implementations, the cottonseed hulls may be fed into the stream by gravity. In yet other implementations, conveying the hulls comprises subjecting the hulls to negative air pressure from the source into the stream. In some implementations, the stream can be free of mechanical obstructions where the cottonseed hulls enter the conduit and downstream therefrom.
[0015] According to another embodiment, a lost circulation material delivery apparatus for delivering lost circulation material from a bulk source of the material into a drilling well mud pit for controlling lost circulation within an oil or gas drilling well bore can include a bulk container of lost circulation material positioned in the vicinity of but removed from the drilling well mud pit. The apparatus can also include a sorting mechanism in receiving communication with the bulk container where the sorting mechanism includes a lost circulation material metering portion. A lost circulation material conveying portion can be in material receiving communication with the material metering portion at a first end portion and in material expelling communication with the drilling well mud pit at a second end portion. The apparatus can also include a lost circulation material driving source spaced apart from the sorting mechanism and coupled to the conveying portion. In operation, the lost circulation material driving source feeds lost circulation material from the material metering portion, through the conveying portion and into the drilling well mud pit.
[0016] In some implementations, the lost circulation material driving source of the apparatus includes at least one electrically powered blower. In certain implementations, the at least one blower generates an air flow within the conveyor to carry the lost circulation material from the sorting mechanism, through the conveying portion and into the drilling well mud pit. In other implementations, the apparatus includes a conduit in receiving communication with the bulk container of lost circulation material at a first end and coupled to a cylindrical housing mounted to the sorting mechanism at a second end opposite the first end. The apparatus can include a conduit coupled to an input of the blower at a first end and the cylindrical housing at a second end opposite the first end. Activation of the blower creates a negative air pressure to draw in lost circulation material from the bulk container.
[0017] In specific implementations, the bulk container can include a bag suspendable above the sorting mechanism and have an opening. Gravity can be used to cause lost circulation material in the bag to pass through the opening and into the sorting mechanism.
[0018] In some implementations, the lost circulation material driving source can be a hydraulically or an electrically powered auger-type mechanism.
[0019] In some implementations, the sorting mechanism can further comprise a separator portion having multiple projecting fin-like elements and positioned above the lost circulation material metering portion.
[0020] In other implementations, the apparatus can include an air moving path and a material moving path and wherein the material moving path does not include the driving source.
[0021] In yet other implementations, the lost circulation material driving source can operate at a substantially constant rate, and wherein the material metering portion is selectively controllable to operate at variable rates.
[0022] The foregoing and other features and advantages of the application will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a perspective front view of an exemplary embodiment of a lost circulation material delivery system.
[0024] FIG. 2 is an elevational left side view of the delivery system of FIG. 1 .
[0025] FIG. 3 is a top plan view of the delivery system of FIG. 2 .
[0026] FIG. 4 is a perspective view of another embodiment of a lost circulation material delivery system using circulation material containing bulk bags.
[0027] FIG. 5 is an elevational side view of the delivery system of FIG. 4 .
[0028] FIG. 6 is an elevational side view of another embodiment of a lost circulation material delivery system using an auger mechanism.
DETAILED DESCRIPTION
[0029] Embodiments of a lost circulation material delivery system for delivering lost circulation material, preferably cottonseed hulls, from a source to a drilling well site are described herein. The drilling well site can include an oil or gas drilling well bore in communication with a mud system, such as a mud pit, configured to prepare and convey drilling fluid or drilling mud into the drilling well bore. The lost circulation material delivery system delivers lost circulation material and introduces it to the mud system to be mixed with the drilling fluid prior to the fluid entering the pit. The various embodiments of the delivery system are configured such that the lost circulation material need not be drawn into and passed through a pump, fan or other material moving device with moving parts along its path to be delivered to the mud system.
[0030] According to one exemplary embodiment, a lost circulation material delivery system is indicated generally at 10 in FIGS. 1-3 .
[0031] Referring to FIG. 1 , the delivery system 10 includes a lost circulation material retrieval passageway, such as hose or pipe 12 , with an inlet end positioned in contact with or near a source, such as, e.g., a van trailer (not shown) with a supply of lost circulation material, and an opposite outlet end coupled generally tangential to an upper portion of a cylindrical hollow cyclone housing 14 . The housing 14 can be mounted to and at least partially supported by a box frame 38 made of multiple reinforcing tubular members. In some implementations, the hose 12 can include a rigid fixed pipe section and a flexible tube section coupled to the pipe section. An air drawing hose or pipe 16 is coupled to an uppermost portion of the cyclone housing 14 , such that it is in air receiving communication with the central channel 31 at one end, and a material moving device, e.g., a fan portion 20 of a pump mechanism 18 , at an opposite end.
[0032] The fan can be driven by a driving device, such as a 20 -horsepower electrical motor 22 , that is coupled to the fan via a belt housed in belt cover 19 and engaged with a shaft of the driving device and the fan. Although a 20 -horsepower electrical motor is shown, it is recognized that other motors having varying power outputs can be used.
[0033] As shown in FIGS. 2 and 3 , the system 10 also includes a sorting portion 26 coupled to a bottom end of the cyclone housing 14 and in hull receiving communication with the housing. The sorting portion 26 includes a funnel, or hopper, portion 27 attached to the cyclone housing 14 at an upper end and a vacuum dropper 30 at a lower end. The funnel portion 27 can have a frustoconical shape or any shape where the upper end of the funnel portion has a larger cross-section than the lower end of the funnel portion.
[0034] A separator 28 is positioned within the funnel portion 27 intermediate the upper and lower ends. In some implementations, the separator 28 includes a stationary horizontally oriented grate-like plate having multiple openings with projecting spaced-apart partitions or fins positioned adjacent the openings. In other implementations, the separator 28 can be movable.
[0035] The vacuum dropper 30 is coupled to a generally elongate rectangular blow box 34 at a lower end and has an opening at its lower end that opens into a material receiving opening in the blow box. The vacuum dropper 30 includes a horizontal rotatable shaft within a housing that is selectively rotated by an electric motor mechanism 41 , such as a motor and gear assembly, coupled to the shaft. The shaft has a series of paddles or fins extending the length of the shaft. The fins can be spaced apart at approximately equal distances from each other.
[0036] The blow box 34 is positioned downstream of the pump mechanism 18 and is separated from the pump mechanism by an enclosed passageway or conduit 32 . The blow box 34 has an inlet end coupled to the enclosed passageway or conduit 32 and an outlet end coupled to a lost circulation material delivery passageway, such as hose or pipe 24 . The hose 24 extends from the blow box 34 to a drilling well mud system, or mud pit, (not shown) that can be located proximate the drilling well. In some implementations, the hose 24 can include a rigid pipe section coupled to a flexible tube section.
[0037] In some implementations, the system 10 can be removably mounted to a transportation vehicle, such as trailer 36 to be transported to an oil or gas drilling well site. In some exemplary implementations, the system can be between approximately 8 and 12 feet high and the pipes or hoses 12 , 16 , 24 can have an approximate internal diameter between about 8 and 14 inches. In a specific implementation, the system 10 is approximately ten feet high and the pipes or hoses 12 , 16 , 24 have an approximate internal diameter of about 10 inches.
[0038] In operation, the electrical motor 22 is selectively operated to drive, or rotate, a fan housed within the fan portion 20 . When rotated, the blades of the fan are oriented to remove air located approximately within the generally cylindrical volume with a cross-section indicated by dashed-line 31 in FIG. 2 from the cyclone housing 14 through pipe 16 to create a vacuum, i.e., negative pressure, which acts to draw in air from the lost circulation material source via hose 12 . The air drawn through the hose 12 urges lost circulation material, such as cottonseed hulls, to be drawn through the hose 12 with the air. The cottonseed hull and air mixture flows through the hose as indicated in FIGS. 2 and 3 until it enters the cyclone housing where the cottonseed hulls are separated from the air as they flow cyclically and downwardly as indicated into the funnel portion 27 until they contact the separator 28 .
[0039] Because of the cyclonic effect of the lost circulation material upon entering the housing 14 , the air within the volume 31 , which is approximately coaxial with the housing, is substantially void of lost circulation material. Accordingly, the pump mechanism 18 , receives the air from the housing 14 via pipe 16 does not receive or interact with lost circulation materials.
[0040] The separator 28 receives the cottonseed hulls, the separator fins separate, or break up, hulls that may be clumped together in masses, and the hulls fall through the multiple openings into the vacuum dropper 30 . Hulls falling through the separator 28 collect in the spaces defined between adjacent fins as the vacuum dropper shaft rotates. Additional rotation causes the hulls collected in each space to fall into the blow box 34 as the shaft rotates to expose the respective spaces to the material receiving opening in the blow box. The rate of rotation of the shaft can be selectively and variably controlled by operation of the motor mechanism 41 to meter the flow or amount of cottonseed hulls allowed to pass into the blow box 34 . In some implementations, the dropper 30 has between 6 and 8 fins and the shaft can be controlled to rotate between about 5 and 60 rpm. In certain implementations, the fins are made of a resilient rubber or elastomeric material.
[0041] Air drawn from the cyclone housing 14 passes through the pump 18 and is expelled or blown into the blow box 34 via hose 32 . The air flowing through the blow box 34 carries the hulls entering the blow box from the dropper 30 into the hose 24 at a relatively constant rate. The hulls are then transported through the hose 24 to the drilling well mud system to be introduced into the drilling fluid.
[0042] Referring now to FIGS. 4 and 5 , another embodiment of a lost circulation material delivery system is indicated generally at 50 and includes a pump 52 with a fan that is selectively driven by a driving device, such as a 10-horsepower electrical motor 53 , to deliver lost circulation material, such as cottonseed hulls, from a source other than a van trailer or truck, such as bulk bag 58 , to a drilling well mud system or mud pit (not shown). Although a 10-horsepower electrical motor is shown, it is recognized that other motors having varying power outputs can be used.
[0043] The bulk bag 58 contains cotton seed hulls and can be suspended from a rigid box frame 56 directly over a sorting portion 62 by a suspension element, such as suspension straps 60 , which can be made from an interwoven fabric mesh, a chain, a spring, or other suitable coupling element or elements. In some implementations, the bulk bag 58 can contain between approximately 1,500 and 2,000 or more pounds of lost circulation material with multiple bulk bags being transportable to and storable at the drilling site.
[0044] The sorting portion 62 can include a surge hopper 64 at an upper first end and a blow box 70 at a lower end. A vacuum dropper 68 , with features similar to vacuum dropper 30 of FIGS. 2-3 , is positioned intermediate the surge hopper 64 and the blow box 70 and a separator 66 , similar to separator 28 of FIGS. 2-3 , can be positioned within the hopper.
[0045] The pump 52 includes an inlet coupled to an air intake passageway 54 and an outlet coupled to a connecting passageway 72 , which couples the pump outlet with an inlet end of the blow box 70 . A lost circulation material delivery passageway, such as hose 74 , can be connected to an outlet end of the blow box 70 at a first end with a second end opposite the first end positioned in ejecting communication with a drilling well mud pit.
[0046] The system 50 can be mounted to a transportable platform 76 , which can be easily transported by a trailer or truck to the drilling well site. In specific implementations, the system 50 can be between approximately 10 and 13 feet high, the frame 56 can be between approximately 4 and 6 feet wide and the pipe 74 can have between an 8- and 10-inch internal diameter. Also, a distance between the horizontal shafts of the separator 66 and the vacuum dropper 68 can be between approximately 1 and 3 feet.
[0047] In operation, a forklift, or other lifting device, lifts a bulk bag 58 containing cottonseed hulls and the suspension elements, each with one end initially secured to either the frame 56 or an upper portion of the bag 58 and the other end coupled to the bag or frame, respectively, suspend the bag from the frame. A sealed pre-formed opening in a lower portion of the bulk bag 58 is unsealed, for example, by untying a knotted rope, and gravity urges the cottonseed hulls to fall into the surge hopper 64 . The separator breaks up hull masses that may have formed and the flow of hulls into the blow box are metered by the vacuum dropper 68 .
[0048] The electric motor is activated to drive the fan, which draws in ambient air via the air intake tube 54 . The air is then expelled or blown out of the pump 52 and into the hose 72 before passing into and through the blow box 70 . The air flowing through the blow box 70 carries the hulls entering the blow box from the dropper 68 into the hose 74 . The hulls are then transported through the hose 64 to the drilling well site at a relatively constant rate to be introduced into the mud pit.
[0049] Referring now to FIG. 6 , another embodiment of a lost circulation material delivery system is indicated generally at 100 and includes an auger-type conveyor portion 102 . Similar to the delivery system 50 of FIGS. 4 and 5 , the delivery system 100 includes a bulk bag 104 containing cottonseed hulls attached to a rigid box frame 106 and suspended over a sorting portion 108 . The sorting portion 108 includes a surge hopper 110 , separator 112 and a vacuum dropper 68 configured to receive hulls from the bulk bag 104 and introduce them into the auger-type conveyor portion 102 in a manner similar to that described above for introducing hulls into the blow boxes 34 , 70 of FIGS. 1-5 .
[0050] The conveyor portion 102 includes a channel, such as pipe 122 , housing a rotating auger 124 and being pivotable about an inlet end 130 . A drive motor 126 is coupled to the auger 124 proximate the inlet end 130 of the pipe 122 to rotatably drive the auger. The pipe 122 is attached to an actuator, such as hydraulic actuator 166 , which is selectively driven by a hydraulic power unit 118 to raise or lower an outlet end 132 of pipe 122 opposite the inlet end 130 .
[0051] In a specific implementation, the pipe 122 can have an approximate internal diameter of approximately 10 inches and the frame 106 can be approximately 12 feet high and 5 . 5 feet wide. The position of the actuator 116 and the length of the pipe 122 can be predetermined to produce a desired vertical and horizontal position of the conveyor portion pipe outlet end 132 . For example, the outlet end 132 can be positioned at approximately 14 feet above the ground.
[0052] In operation, the cottonseed hulls from the bulk bag 104 pass through the sorting portion 108 in a manner similar to that described above as relating to the sorting portion 62 shown FIGS. 4-5 , except that instead of being introduced into a blow box, the hulls are introduced into the conveyor portion 102 . The drive motor 126 rotates the auger 124 such that the auger blades continually shift or convey the hulls upward along the pipe 122 at a relatively constant rate until the hulls are expunged through an opening 134 in the pipe proximate its outlet end 132 and fall, or are otherwise introduced, into a drilling well mud system or pit (not shown).
[0053] The system 100 can be mounted to a transportable platform 120 that can be moved to a location proximate the drilling well or mud pit. The actuator 116 can be selectively extended and retracted to raise and lower, respectively, and move rearwardly and forwardly, respectively, the outlet end of the pipe 122 such that the hulls exiting the opening in the outlet end fall into the drilling well mud system.
[0054] In several implementations, many of the rigid components of the illustrated embodiments, such as the cyclone housing, frames, rigid sections of the pipes and sorting portion components, can be made from steel, while the flexible components, such as the flexible sections of the pipes, can be made from an elastomeric or plastic material.
[0055] Although one preferred lost circulation material is cottonseed hulls, other lost circulation materials, such as cedar fiber, paper, cottonseed burrs, sawdust, cellophane, calcium carbonate, phenolic plastic or other material that can be used as an additive in the drilling fluid to fill fissures, porous or fractured formations, or other undesirable subterranean characteristics existing or formed in the side walls of the well bore, can also be used in the described systems and methods.
[0056] In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims. We therefore claim as our invention all that comes within the scope and spirit of these claims. | Disclosed herein are embodiments of a method and system for delivering lost circulation material, particularly cottonseed hulls, into oil and gas drilling pits. According to one exemplary embodiment, a method of delivering lost circulation material from a bulk source to a drilling well mud system for controlling lost circulation within a drilling well bore includes positioning a bulk container of lost circulation material at a location in the vicinity of but removed from drilling well mud system. Lost circulation material is introduced from the bulk container into a sorting mechanism. The method further includes conveying the lost circulation material with a moving device from the sorting mechanism to the drilling well mud system along a path separated from the moving device. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application No. 60/474,670, filed May 30, 2003, the subject matter of which is fully incorporated herein by reference.
FIELD OF INVENTION
This invention relates to antiviral molecular biology. More particularly, it relates to the isolation and identification of an active truncated form of the RNA polymerase of flavivirus, capable of being easily reproduced, and serving as a target for high-throughput screening of antiviral drugs.
BACKGROUND
The genus flavivirus contains approximately 70 positive single-stranded RNA viruses, among which many major human pathogens are found, including Dengue virus (“DV”), West Nile (“WNV”), Yellow Fever virus (“YFV”), Japanese and tick-borne encephalitis viruses. YFV was the first flavivirus to be isolated in 1927, but historically, flavivirus-like diseases have been reported in the medical literature since at least 1780.
On of the most common and virulent flaviviruses is DV. DV threatens up to 2.5 billion people in 100 endemic countries. Up to 50 million infections occur annually with 500 000 cases of dengue haemorrhagic fever and 22,000 deaths mainly among children. Dengue has been classified by the World Health Organization (“WHO”) as a priority as it ranks as the most important mosquito-borne viral disease in the world. In the last 50 years, its incidence has increased 30-fold. Prior to 1970, only 9 countries had experienced cases of dengue haemorrhagic fever (“DHF”); since then the number has increased more than 4-fold and continues to rise.
WNV also has become much more wide-spread. In 1999, WNV was isolated for the first time in the Americas during an outbreak in New York City. By the end of 2002, WNV activity had been identified in 44 states of the United States and the District of Columbia. The 2002 WNV epidemic resulted in 4,156 reported human cases of WN disease including 2,942 meningoencephalitis cases and 284 deaths.
There have been previous attempts to generate a vaccine. For example, a live, attenuated virus of YFV (strain 17D) was developed in 1936 and has been used as a vaccine for over 400 million people. Unfortunately, the vaccine has not proved 100% successful since there are 200,000 estimated cases of yellow fever (with 30,000 deaths) per year worldwide, 90% of which in Africa. Chimeric live vaccines incorporating genes of either Japanese encephalitis, WNV, or Dengue in a YFV 17D vector are currently in development. However, a number of difficulties are associated with the conception of safe and efficient vaccines, such as vaccine purity, and immunogenic cross responses. That is why antiviral chemotherapy has a major role to play in the control of such diseases.
Since viral RNA polymerase is critical for replication of the virus and cannot be substituted by any other cellular polymerase, it is an excellent antiviral target. As a result, most of the more than 30 new antiviral agents, which have been developed and approved during the last 5 years, are directed against viral polymerases. They are mainly targeted against human immuno-deficiency virus, but drugs against hepatitis B and C, herpes simplex, varicella-zoster and influenza virus infections have also been made commercially available.
More than 50% of these antiviral agents are nucleoside analogues, in which the base, the ribose moiety or both have been modified. Nucleoside analogues can act as inhibitory ligands by binding to the template binding site within the polymerase active site and preventing the access of the viral RNA, or by binding to the nucleotide binding site, thus limiting the availability of the natural substrate for complementary strand synthesis. It is generally understood in the art that a nucleoside analogue may be a synthetic molecule that resembles a naturally occurring nucleoside, but lacks a bond site needed to link it to an adjacent nucleotide. Additionally, nucleoside analogues can also act as chain-terminators during DNA or RNA synthesis, by binding themselves as a substrate for the target polymerase, but preventing further chain elongation. Non-nucleoside analogues may bind to allosteric sites thus influencing the local conformation of the active site via long-range conformational changes of the polymerase's structure.
Another approach whereby many antiviral compounds have been discovered is by using cell cultures infected with the virus of interest. In such cases, addition of an antiviral compound protects the cells from infection, or inhibits virus growth. For this type of experiment, it is useful to identify a large number of antiviral compounds in an efficient manner. As such, another evolving mechanism to identify new antiviral agents through the high-throughput screening (“HTS”) of a large number of synthetic or natural compounds. This requires the development of an in vitro assay, which in turn requires large amounts of soluble and active protein.
When a high number of potentially antiviral compounds are tested by HTS, it is possible to identify antiviral compounds in an efficient manner. This approach has been used successfully for HIV and other viruses. However, in some cases, this approach is difficult due to the absence of a suitable system allowing infection of a cell in vitro.
In other cases, even if a suitable cell-based assay is available, this procedure may be too cumbersome or expensive. This is the case for certain dangerous viruses—such as those that require BSL-3 and/or BSL-4 facilities. Establishing a screening process for over a large amount of compounds in a BSL-3 or BSL-4 containment facility has not been achieved yet because of this heavy expense and burden. For example, flaviviruses belong to this class of viruses. These viruses require from BSL-2 to BSL-4 facilities (e.g., Dengue, WNV and/or Kyasanur Forest viruses). Thus, in such cases, it is preferable to screen potentially antiviral compounds directly on viral target proteins.
For efficiency, especially considering the difficulty with certain, more dangerous viruses, the characterization in molecular terms of the target, the viral polymerase, is of prime importance in the screening and selection of antiviral compounds. In the case of the flavivirus RNA polymerase (“NS5” or sometimes referred to herein as “NS5Pol”), this task has proven to be difficult for several reasons. First, polymerase genes have been notoriously difficult to clone in their entirety. When available, recombinant NS5 has been reported to be unstable in bacterial hosts. In addition, the notoriously low yield of soluble purified NS5 is a limiting factor to set up polymerase-activity assays. Another possible reason for the described difficulties is the fact that NS5 does not carry a single enzymatic activity.
Very recently, we described an N-terminal domain of NS5 (sometimes referred to herein as “NS5 methyltransferase domain”) which acts as an S-adenosyl-L-methionine (AdoMet)-utilizing RNA-cap 2′Omethyltransferase, thus participating in mRNA capping, which is generally understood as the process of adding a guanosine nucleotide to the 5′ end of mRNA (the methelyated end of guanosine) (Egloff & Benarroch, 2002). Additionally, we showed that the NS5 methyltransferase domain binds GTP analogues.
Due to the nature and proximity of the NS5 methyltransferase domain to the polymerase domain of the flavivirus, the description and characterization of the NS5 methyltransferase domain clearly shows that some nucleoside analogues and inhibitors of flavivirus replication could potentially be, in fact, mRNA-capping inhibitors without any effect on the polymerase activity. Likewise, it is very possible to mistakenly identify a compound as binding to NS5 and characterizing the binding data as potentially interesting for inhibition of the polymerase, but, in reality, only the RNA-capping has been affected. Therefore, it would be useful to identify and define the “junction” or sequence between the NS5 methyltransferase domain and the polymerase domain.
SUMMARY OF THE INVENTION
This invention relates to the isolation and purification of a polypeptide from a flavivirus.
In another aspect of the invention, the polypeptide can be separated into two domains, the N-terminal domain and the C-terminal domain, both of which are separately active.
In another aspect of the invention, the junction between the N-terminal and C-terminal domains has been identified.
In yet another aspect of the invention, the results indicated that independent expression of each of the separated domains provided greater expression than the full, unseparated polypeptide.
In still another aspect of the invention, the C-terminal of the domains in particular is purified and acts as active RNA polymerase.
In yet another aspect of the invention, the C-terminal domain demonstrates substantial homology with other RNA polymerases of clinical interest.
In still another aspect of this invention, the polymerase provides a surrogate model and system to screen synthetic and natural compounds against the polymerases of related viruses.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows the sequence alignment of NS5 of flaviviruses: Dengue2 (SEQ ID NO. 1); Dengue3 (SEQ ID NO. 2); Dengue1 (SEQ ID NO. 3); Dengue4 (SEQ ID NO. 4); WestNile (SEQ ID NO. 5); Kunjin (SEQ ID NO. 6); JapaneseEncephalitis (SEQ ID NO. 7); YellowFever (SEQ ID NO. 8); Banzi (SEQ ID NO. 9); Langat (SEQ ID NO. 10); Powassan (SEQ ID NO. 11); Tick-borneEncephalitis (SEQ ID NO. 12); LoupingIll (SEQ ID NO. 13); Modoc (SEQ ID NO. 14); RioBravo (SEQ ID NO. 15).
FIG. 2 shows two Western blots illustrating the expression and purification of NS5DV and NS5Pol DV .
FIG. 3 shows a Western blot ( FIG. 3A ) and a graph ( FIG. 3B ) of the purified NS5Pol DV .
FIG. 4 shows two graphs ( FIG. 4A and FIG. 4B ) demonstrating the activity level of NS5Pol DV on poly(rC).
FIG. 5 shows a steady-state Km determination of GTP with and poly(rC) (in FIG. 5A ) and for monomeric NS5PolDV using poly(rC) without primer (de novo initiation) (in FIG. 5B ).
FIG. 6 shows divalent cation optimum curves for NS5PolDV and NS5PolWNV (in FIG. 6A ) on poly(rC) without primer (de novo initiation) (in FIG. 6B ).
FIG. 7 shows two graphs demonstrating the activity level of of NS5PolDV on specific heteropolymeric RNA templates.
DETAILED DESCRIPTION
Definitions
“Structural equivalents” should be understood to mean a protein maintaining its conformational structure as if the protein were the native protein expressed in its natural cell.
“Substantial homology” or “substantially homologous” means a degree of homology between the isolated and described NS5Pol (as defined herein) and the RNA polymerases of other positive-single-stranded RNA viruses of clinical interest when there is homology at least about 65%, preferably at least about 70%, most preferably in excess of 80%, and even more preferably in excess of 90%, 95% or 99%.
Results and Findings
In one aspect of this invention, we discovered a way to circumvent the above-described problems associated with viral polymerase. We performed a structural analysis of flaviviruses NS5 genes using biocomputing methods, and isolated and defined two unique domains of NS5. As described in the literature, two distinct domains are generally defined for the large family of flavivirus NS5 genes, and related structural equivalents.
Specifically, as shown in the experiments, NS5 was separated into the two domains using genetic engineering techniques. We have established the independent folding of these two putative domains using various methods. Moreover, demonstrated in our experiments as set forth below, each domain is separately active, and an appropriate ligand may be mapped to either the N-terminal (capping) domain or the C-terminal (polymerase) domain of NS5. These genetic constructs allow the production of higher quantities of either domain compared to the full-length protein. Thus, simply put, the C-terminal polymerase domain of NS5 (NS5Pol) of DV (subtype 2, Strain New Guinea C), WNV (strain New York 99) and the Kunjin variant of WVN (KV) are easy to purify in large quantities, they are active as a polymerase, and constitute one aspect of our invention.
As noted, the availability of large quantities of NS5Pol allows its use as a target in HTS. One of the advantages of the isolation of the polymerase domain is that the antiviral compound, which demonstrates the modulating activity of the polymerase domain, is specific to the polymerase activity of the viral protein, without any interference of the other parts of the protein. Indeed, it is possible to detect RNA polymerase activity in a single tube using standard radioactive or nonradioactive methods.
As described herein, modulation of the polymerase activity of the protein is important in creating antiviral agents for the treatment of the enumerated viral diseases. Since DV, WNV and KV NS5Pol domains are significantly homologous to and demonstrate substantial homology with NS5Pol domains of other flaviviruses, and since DV, WNV and KV NS5Pol are functionally homologous to the RNA polymerases of other positive-single-stranded RNA viruses of clinical interest (such as the related NS5B polymerase of HCV), NS5Pol provides also a surrogate model and system to screen synthetic and natural compounds against such related viruses. Simply put, the invention includes a method of screening antiviral compounds able to modulate the polymerase activity of significantly and functionally homologus NS5 gene encoding viruses (i.e. flaviviruses).
Expression and Purification
Based on preceding structural and functional studies on a N-terminal methyltransferase or capping domain of protein NS5 of flavivirus (Egloff and Benarroch, 2002) we predicted the limit of a functional and soluble C-terminal polymerase domain of NS5. In particular, FIG. 1 identifies the sequence alignment of various flaviviruses as follows: Dengue 2 (P14340) (SEQ ID NO. 1), Dengue 3 (Q99D35) (SEQ ID NO. 2), Dengue 1 (Q8VBS3) (SEQ ID NO. 3), Dengue 4 (AAA42964) (SEQ ID NO. 4), West Nile virus (AAL87234) (SEQ ID NO. 5), Japanese encephalitis virus (Q82872) (SEQ ID NO. 7), Yellow fever virus (Q89277) (SEQ ID NO. 8), Banzi virus (Q67483) (SEQ ID NO. 9), Langat virus (Q9IG40) (SEQ ID NO.10), Tick-borne encephalitis virus (Q8VBS4) (SEQ ID NO. 12), Louping ill virus (O10383) (SEQ ID NO. 13), Modoc virus (CAC82912) (SEQ ID NO. 14) and Rio Bravo virus (Q9JAD5) (SEQ ID NO. 15) were aligned by ClustalW. The secondary-structure elements of the NS5MTaseDV structure as determined by X-ray crystallography and of NS5PolDV as predicted by PredictProtein are displayed in black and red, respectively, above the sequence of NS5 Dengue. NS5Pol starts after the vertical bar just before a predicted alpha-helix. The remaining ca. 550 residues of NS5 are not shown.
As set forth above, FIG. 1 shows the sequence alignment of the N-terminal part of NS5 of several flaviviruses with the secondary structure elements of the capping domain of Dengue NS5 given above. Essentially, as discussed, the junction between the methyltransferase and polymerase portion of the flaviviruses was isolated, which allows the precise and efficient separation of the domains. The junction (or where the Pol domain starts) is located at amino acid 272.
Proteins NS5 and their corresponding Pol domains of DV, KV and WNV were expressed as recombinant proteins bearing a His-tag which facilitates subsequent purification. Accordingly, they were purified with immobilized metal-affinity chromatography (IMAC) in a first purification step. As noted above, FIG. 2 illustrates the superiority of NS5PolDV over NS5DV in terms of purification yield after IMAC following the same protocol. The results shown in FIG. 2 , the expression and purification of NS5DV and NS5PolDV, were obtained as follows: NS5DV and NS5PolDV were cloned in expression plasmid pQE30, expressed in BL21[pDNAy] overnight at 17° C. after induction with 50 mM IPTG, addition of 2% EtOH and a cold shock (30 min at 4° C.). Sonication was done in 50 mM sodium phosphate lysis buffer, pH 7.5, 300 mM NaCl, 10% glycerol (10 ml of this lysis buffer for 3.6 g cell pellet) in the presence of DNAse, PMSF, protease inhibitors and lysozyme. Recombinant proteins were bound to metal-affinity-chromatography resin talon (Clontech) and eluted with 500 mM imidazole. SDS-PAGE of protein samples from expression and purification: upper panel: NS5DV, lower panel: NS5PolDV, lane 1: total fraction after lysis, lane 2: soluble fraction after lysis and centrifugation, lane 3: flowthrough of metal-affinity column, lane M: molecular mass markers, lanes 4 to 8: eluted fractions from metal-affinity column, F1 to F5, lane 9: metalaffinity resin. The corresponding molecular masses in kD of the markers are given on the left. NS5DV results in low purification yields due to instability resulting in the presence of a protein band the size of which corresponds to the polymerase domain (see arrow in the upper panel).
The low yield of NS5 is attributed to lower solubility of the recombinant protein and an elevated sensitivity to proteolytic cleavage during purification. This is illustrated in FIG. 2 by the presence of a cleavage product of around 73 kD which could represent the Pol domain. Yields for both proteins are compared in Table 1.
TABLE 1
Yield after expression and purification
Yield (mg per liter expression culture)
protein
after IMAC
after heparin
NS5Pol DV
2
1.2
NS5 DV
0.2
n.d.
NS5Pol KV
10
7
NS5 KV
7
0.6
NS5Pol WNV
12
8
NS5 WNV
n.d.
n.d.
A second purification step consists of heparin affinity chromatography. The results of this purification were illustrated in FIG. 3 and obtained pursuant to the following procedure: NS5PolDV eluates from metal-affinity chromatography were dialyzed against 50 mM sodium phosphate buffer, pH 7.5, 150 mM NaCl, 10% glycerol and submitted to heparin-affinity chromatography applying a salt gradient of 150 mM to 1M NaCl. Pure protein was eluted in two peaks, at 390 mM and 460 mM NaCl.
A: SDS-PAGE of protein samples from purification steps, lane 1: pooled protein fractions from metal-affinity chromatography after dialysis, lane M: molecular mass markers, lane 2: peak 1 from heparin-affinity chromatography, lane 3: peak 2 from heparin-affinity chromatography, lane 4: flowthrough from heparin-column. The corresponding molecular masses in kD of the markers are given on the left.
B: Analytical gel filtration (Superdex 200, Pharmacia) of peak 1 and 2 of NS5PolDV from heparin affinity chromatography. The elution volume of peak 1 corresponds to the monomeric form of NS5PolDV whereas peak 2 elutes earlier corresponding to oligomeric NS5PolDV (trimer or tetramer).
For NS5PolDV it results in two fractions eluting at different salt concentrations both representing NS5PolDV, as shown in FIG. 3A . Analytical gel filtration showed that peak 1 from heparin affinity chromatography represents the monomeric form of NS5PolDV whereas peak 2 represents an oligomeric form as shown in FIG. 3B . Both forms are purified to 98% after heparin purification step, the combined yield of NS5PolDV is 1.2 mg starting from one liter expression culture (Table 1).
Expression and purification of NS5 KV and NS5PoIKV follow a similar tendency compared to Dengue NS5 (sequence identity of NS5 66.4%). Although full-length NS5 KV and NS5PolKV render considerably higher yields compared to the corresponding Dengue proteins, still, full-length NS5 KV shows lower yields after one purification step (Table 1) and, due its instability, dramatically lower yields after a second purification step. In difference to NS5PolDV, NS5PolKV elutes as a single peak after heparin affinity chromatography (data not shown). The same applies to NS5PolWNV (sequence identity to NS5PolKV 94.6%).
In all cases, the final purification product, for which the purity is adequate for HTS assays, is purified with a >10-fold increase in yield compared to the unengineered polymerase.
Activity Data
Polymerase activity on NS5Pol was measured on homo- and heteropolymeric templates.
Homopolymeric Template
Activity was tested on three homopolymeric templates: poly(rC), poly(rU) and poly(rA). Only poly(rC) resulted to be a productive template for NS5PolDV. This was illustrated in FIG. 4 based on the following protocol: RNA polymerase activity was tested on a homopolymeric RNA template (polycytidylic acid, Amersham Biosciences) of an average length of 360 nt. A standard assay was carried out in 50 mM HEPES buffer, pH 8.0, 10 mM KCl, 5 mM MgCl2, 5 mM MnCl2, 10 mM DTT containing 1 μM template, 4 mM primer GG, 10 μM GTP, 0.01 mCi [3H]-GTP per μl reaction mixture and the concentration of enzyme given below. Reactions were carried out at 30° C. for given time periods and stopped by spotting a sample on DEAE filter discs (Whatman) presoaked with 50 mM EDTA. Filters were washed 3×10 min with 300 mM (NH4)2SO4 buffer, pH 8.0 and 2×5 min with EtOH and air-dried. Liquid scintillation fluid was added and incorporation in counts per minute (cpm) determined by using a Wallac MicroBeta TriLux Liquid Scintillation Counter.
A: Influence of specific E. coli RNA polymerase inhibitor rifampicin on NS5PolDV and E. coli polymerase (control). NS5PolDV was tested using the conditions given above at 64-nM enzyme concentration. E. coli RNA polymerase was obtained from USBiochemicals and used in NS5PolDV standard rection buffer at 37 nM.
B: Time course of [3H]-GTP incorporation by NS5PolDV peak 1 (monomeric preparation) and peak 2 (oligomeric preparation) from heparin 11 affinity chromatography (see FIG. 3A ) tested at 80 nM enzyme concentration using poly(rC) without primer.
FIG. 4A shows incorporation of radioactively labeled GTP into a nascent poly(rG) polymerization product by NS5PolDV (oligomeric preparation) using primer rGG. In a control reaction E. coli RNA polymerase-inhibitor rifampicin was added and did not show any inhibitory effect. Thus, the observed incorporation of radioactive GTP in a polymerization product is not due to a contamination with E. coli RNA polymerase activity. FIG. 4B shows a parallel test of the oligomeric and monomeric preparation of NS5PolDV. In this experiment no primer was used, thus, polymerization is initiated de novo. Both preparations show identical catalytic efficiency. There are two possible explanations, either the state of oligomerization does not influence polymerase activity or under the conditions of the activity test (80 nM enzyme 6 concentration) both preparations adopt the same oligomerization state. In either way, both preparations can likewise be used for inhibitor screening studies.
In FIG. 5 , the steady-state Km determination of GTP with various ligands was performed as follows: RNA polymerase activity was tested under conditions given in the description set forth above in the experiments related to FIG. 4 without the use of a primer. Initial velocities were determined over a time period of 5 min. GTP concentrations in the range of 2 to 500 μM were tested using poly(rC) at 1 μM. Template poly(rC) was tested in the range of 2 to 1000 nM with GTP fixed at 200 μM.
A: Plot of apparent intitial velocity (viapp in cpm per min) against GTP concentration. Data were fitted to a Michaelis-Menten hyperbola (viapp=Vmax[S]/(Km+[S]) using Kaleidagraph.
B: Plot of apparent initial velocity against poly(rC) concentration. Data were fitted as in A.
The Km of GTP was determined for NS5PolDV (monomeric preparation) as being 27.3±5.1 mM ( FIG. 5A ). Km values are in a similar range for the oligomeric preparation of NS5PolDV (66.2±6.6 mM) and for full-length NS5DV (13.0±2.9 mM). Thus, the affinity of NS5PolDV from both preparations versus the substrate GTP that binds to a nucleotide-binding site within the active site of the enzyme are close. This again confirms that both preparations can be used likewise. Additionally, the fact that NS5PolDV shows similar substrate affinity as NS5 indicates that the polymerase domain of flavivirus NS5 is a valid model system for the identification of inhibitors of the full-length protein. The Km values of polyC were determined for the monomeric preparation of NS5PolDV as 17.3±2.4 mM, the oligomeric preparation as 14.8±3.8 mM and for NS5DV as 18.0±7.3 mM. As seen above, the corresponding plot for the monomeric preparation of NS5PolDV is shown in FIG. 5B . First, this allows the conclusion that a putatively different oligomerization status of NS5PolDV does not seem to influence the affinity to a long template which could be expected to maintain cooperative interactions with two enzyme molecules at the same time. Secondly, template poly(rC) (around 360 nt long) shows identical affinity to NS5DV and NS5PolDV within the context of its use as a polymerization template. Thus, the capping domain does not seem to be involved in template binding indicating again that the isolated polymerase domain can be used for inhibitor screening experiments of the polymerase activity of full-length NS5.
FIG. 6A shows the optimum curve for divalent manganese (Mn) and magnesium (Mg) ions of NS5PolDV on poly(rC). Polymerization on poly(rC) works exclusively in the presence of Mn ions. This is also the case for NS5PolWNV as shown in FIG. 6B . The results set forth in FIG. 6 were obtained pursuant to the following protocol:
A: Tests of NS5PolDV were carried out under standard conditions given in the description set forth above in the experiments related to FIG. 4 at 60 nM enzyme concentration. Influence of Mn2+ was tested either in absence of Mg2+ (Mn) or in presence of 5 mM Mg2+ (Mn (5 mM Mg)). Mg2+ was tested in the absence of Mn2+ (Mg).
B: Test of NS5PolWNV were carried out under the same reaction conditions as for NS5PolDV with the exception of GTP which was used at 100 μM. NS5PolWNV concentration was 400 nM.
Clearly, as seen from FIGS. 6A and 6B , the optimum curves for Mn2+ show that NS5PolWNV tolerates higher Mn2+ concentrations for the polymerization on polyC than NS5PolDV. The apparent Km value for substrate GTP is around 2 to 4-fold higher (130 mM) for NS5PolWNV and NS5PolKV in comparison to NS5PolDV (data not shown). These mechanistic differences between flavivirus polymerases can be studied in detail using well expressed and stable independent NS5Pol domains.
Heteropolymeric Template
NS5PolDV activity was tested on heteropolymeric specific templates comprising 717 nucleotides (225 nt of the 5′ and 492 nt of the 3′ of the Dengue genome). Specifically, the results are demonstrated in FIG. 7 and were obtained pursuant to the following protocol: Heteropolymeric RNA templates of 717 nt were generated by in vitro transcription using T7 RNA polymerase. The DNA template containing 225 nt of the 5′ and 492 nt of the 3′ of Dengue genomic RNA was constructed into plasmid pUC18. PCR products with the T7 promoter on the 5′ of the positive-sense strand or the 5′ of negative-sense strand were generated and used as substrates for in vitro transcription. RNA templates were replicated by NS5PolDV in 50 mM HEPES buffer, pH 8.0 containing 10 mM KCl, 10 mM DTT, 100 nM RNA template, 200 nM NS5PolDV, 500 mM ATP, UTP, GTP, 10 mM CTP and [a-32P]-CTP at 0.1 mCi/ml. Reactions were carried out at 30° C. and stopped by spotting a sample on DEAE 12 filter discs (Whatman) pre-soaked with 50 mM EDTA. Filters were treated as explained above in the experiments related to FIG. 4 .
A: Comparison of incorporation on positive-sense and complementary negative-sense minigenome RNA templates. Reactions were carried out as given above except for the use of 500 mM CTP, 50 mM GTP, 0.1 mCi/ml [a-32P]-GTP and 5 mM Mn2+.
B: Divalent-cation optimum curves on positive-sense specific RNA template. Mn2+ was used in the absence of Mg2+ and, likewise, Mg2+ in the absence of Mn2+. Reaction were stopped after 60 min. Incorporation of CMP is given in cpm. The axis on the left corresponds to values obtained in presence of Mn2+ and the axis on the right to values obtained in presence of Mg2+.
This “minigenome” template illustrated in FIG. 7 contains secondary-structure and sequence elements necessary for efficient 7 de novo initiation and replication. Positive-sense and negative-sense RNA was generated by in vitro transcription from PCR products containing the promoter for T7 RNA polymerase in either sense. Specifically, FIG. 7A illustrates that NS5PolDV replicates negative-sense mini-genome RNA with higher efficiency compared to positive-sense RNA. This observation is in accordance with the observation that 10-times more positive-sense genomic RNA is produced in Dengueinfected cells in comparison to negative-sense RNA. Optimum divalent cation concentration (Mn2+ and Mg2+) was determined for replication of the positive-sense template ( FIG. 7A ). NS5PolDV replicates the template with 20-fold higher efficiency at optimal Mn2+ concentration compared to optimal concentration of Mg2+. The affinity of Mn2+ to active site residues seems to be higher compared to Mg2+ as the optimum concentration is lower.
Selective Inhibition of Dengue Virus Polymerase Activity Using Nucleotide Inhibitors
GTP analogs were used on NS5PolDV and NS5PolWNV to demonstrate their capacity to inhibit the NS5 polymerase domain using the homopolymeric template poly(rC). IC50 values were determined using GTP concentrations close to the determinded Km values (10 mM for NS5PolDV and 100 mM for NS5PolWNV). Table 2 shows the determined values of three putative chain terminators (3′-deoxy GTP, 3′-dioxolane 3′-deoxy GTP and 2′,3′-dideoxy GTP) and 2′-O-methyl-GTP which is expected to be incorporated into the growing RNA chain, thus acting as a competitive inhibitor.
TABLE 2
IC50 values for selected GTP analogs
Reactions on poly(rC) were done under conditions given in FIG. 4
without a primer. NS5PolDV was used at 60 nM. Incorporation of
[3H]-GTP was measured after 15 min. Inhibitors (TriLink Corp.)
were tested in the concentration range of 1 nM to 100 mM.
IC50 (μM)
inhibitor
NS5Pol DV
NS5Pol WNV
3′-deoxy GTP
0.02
0.18
3′-dioxolane 3′-deoxy GTP
1.2
58
2′,3′-dideoxy GTP
0.8
30
2′-O-methyl-GTP
5.6
105
The capacity of 2′-O-methyl-GTP (10 mM) was compared to inhibit NS5PolDV (dimeric preparation) and full-length NS5DV. Initial velocities were determined on poly(rC) at 10 mM GTP and compared to corresponding values without inhibitor. Initial velocities were determined to be 29.3% for NS5PolDV (dimeric preparation) and 19.3% for NS5DV compared to the proteins without inhibitor. This indicates that the NS5PolDV preparation is less inhibited than the full-length polymerase. Since these inhibition results are not identical, questions related to the putative interference of the capping domain remain when using the full-length polymerase.
It is clear that the removal of the capping domain (methyltransferase domain) which is able to bind GTP and GTP analogs, at the N-terminus of NS5 provides the opportunity to obtain unambiguous data which will show that the present truncated polymerase is the target of these inhibitors. The same applies to non-nucleoside inhibitors.
CONCLUSION
To summarize our results: the polymerase domain of flavivirus NS5
1. is purified with higher yields than full-length NS5. The overall increase in yield of the purified product suitable for HTS assays is >10-fold, facilitating mass production for HTS assays.
2. is much more stable than full-length NS5, as less protein is lost or degraded during the course of purification, giving a cleaner and more homogeneous reagent.
3. is active on homopolymeric and heteropolymeric specific templates. Thus, the capping domain is not necessary for the polymerase activity defined as the capacity to initiate and incorporate nucleotides into RNA. The polymerase domain defined here is a bonafide polymerase useful to conduct drug-screening assays.
4. shows similar affinities for template and substrates as the full-length NS5, and is identical in all points tested in terms of polymerase activity.
5. is unambiguous about being the target of a potential inhibitor. As the capping domain is not present, inhibition of NS5 function by GTP analogues and other molecules cannot be accounted for by inhibition of the capping domain or indirect inhibition of the NS5 polymerase activity by interference of the inhibitor with the capping domain.
6. is a valid polymerase model to conduct inhibitor screening studies with the aim to identify putative inhibitors of flavivirus RNA polymerases.
Baginski S G, Pevear D C, Seipel M, Sun S C, Benetatos C A, Chunduru S K, Rice C M, Collett M S. “Mechanism of action of a pestivirus antiviral compound.” Proc Natl Acad Sci USA 2000, 97:7981-6. Campiani G, Fabbrini M, Morelli E, Nacci V, Greco G, Novellino E, Maga G, Spadari S, Bergamini A, Faggioli E, Uccella I, Bolacchi F, Marini S, Coletta M, Fracasso C, Caccia S. “Non-nucleoside HIV-1 reverse transcriptase inhibitors: synthesis and biological evaluation of novel quinoxalinylethylpyridylthioureas as potent antiviral agents.” Antivir Chem Chemother 2000, 11:141-55. Carroll S S, Tomassini J E, Bosserman M, Getty K, Stahlhut M W, Eldrup A B, Bhat B, Hall D, Simcoe A L, LaFemina R, Rutkowski C A, Wolanski B, Yang Z, Migliaccio G, De Francesco R, Kuo L C, MacCoss M, Olsen D B. “Inhibition of hepatitis C virus RNA replication by 2′-modified nucleoside analogs.” J Biol Chem 2003 278:11979-84. De Clercq E. “Antiviral drugs: current state of the art.” J. Clin. Virol. 2001:73-89. Egloff M P, Benarroch D, Selisko B, Romette J L, Canard B. “An RNA cap (nucleoside-2′-O—)-methyltransferase in the flavivirus RNA polymerase NS5: crystal structure and functional characterization.” EMBO J. 2002 21:2757-68. Khandazhinskaya A L, Shirokova E A, Skoblov Y S, Victorova L S, Goryunova L Y, Beabealashvilli R S, Pronyaeva T R, Fedyuk N V, Zolin V V, Pokrovsky A G, Kukhanova M K. “Carbocyclic dinucleoside polyphosphonates: interaction with HIV reverse transcriptase and antiviral activity.” J Med Chem 2002, 45:1284-91. Lai M M. “RNA polymerase as an antiviral target of hepatitis C virus.” Antivir Chem Chemother 2001, 12 Suppl 1:143-7. Mentel R, Kurek S, Wegner U, Janta-Lipinski M, Gurtler L, Matthes E. “Inhibition of adenovirus DNA polymerase by modified nucleoside triphosphate analogs correlate with their antiviral effects on cellular level.” Med Microbiol Immunol (Berl) 2000, 189:91-5. Mlinaric A, Kreft S, Umek A, Strukelj B. “Screening of selected plant extracts for in vitro inhibitory activity on HIV-1 reverse transcriptase (HIV-1 RT).” Pharmazie 2000, 55:75-7. Walker M P, Hong Z. “HCV RNA-dependent RNA polymerase as a target for antiviral development.” Curr. Opinion Pharmacol. 2002, 2!:1-7. Wang M, Ng K K, Cherney M M, Chan L, Yannopoulos C G, Bedard J, Morin N, Nguyen-Ba N, Alaoui-Ismaili M H, Bethell R C, James M N. “Non-nucleoside Analogue Inhibitors Bind to an Allosteric Site on HCV NS5B Polymerase.” CRYSTAL STRUCTURES AND MECHANISM OF INHIBITION. J Biol Chem 2003 278:9489-95. Zoulim F. “Therapy of chronic hepatitis B virus infection: inhibition of the viral polymerase and other antiviral strategies.” Antiviral Res 1999, 44:1-30. | The isolation and purification of two domains from a from a flavivirus is provided. Each domain can function independently. Moreover, one domain codes for a sequence that provide polymerase activity. A process for screening possible modulators of the polymerase activity of an isolated and purified polypeptide from flavivirus is also disclosed. | 2 |
This is a division of application Ser. No. 230,617, filed Feb. 2, 1981. Now U.S. Pat. No. 4,374,000.
BACKGROUND OF THE INVENTION
This invention relates to a process and apparatus for producing readily polymerizable vinylaromatic compounds. More particularly, this invention relates to a process and apparatus for inhibiting the accumulation of undesired polymeric material on the undersides of the seal pans of a distillation column during distillative purification of vinylaromatic monomers.
Vinylaromatic monomers, such as styrene, alpha-alkylstyrene, vinyltoluene, divinylbenzene and the like, are important for their ability to form useful polymer materials. These compounds are typically prepared by catalytic dehydrogenation of alkylaromatic compounds having corresponding carbon chains. The crude product of the dehydrogenation reaction, however, is a mixture of materials comprising in addition to the desired vinylaromatic monomer, various alkylaromatic compounds as well as oligomers of the desired monomer. These other substances must be separated from the vinylaromatic monomer to obtain a commercially acceptable product.
The usual method for separating a desired vinylaromatic monomer from the dehydrogenation product mixture is to pass the mixture through a distillation train in which lower boiling materials are first separated and then the desired monomer is distilled from the higher boiling materials. Such distillative separations are complicated by the fact that the tendency of the monomer to polymerize increases with increasing temperature. Thus, as the mixture is heated to distill it, the formation of undesired polymer increases and the yield of desired monomer decreases.
Various measures have been utilized to minimize the undesired polymer formation. Vacuum distillation, i.e. distillation at subatomspheric pressures, has been resorted to to reduce the temperature to which the feed mixture must be heated. While this is helpful in reducing the formation of undesired polymeric material, substantial amounts of polymer still are formed.
Polymerization inhibitors have also been added to the feed mixture. Known inhibitors further reduce the formation of undesired polymer, but still are not totally effective. Moreover, such inhibitors may be expensive and contribute substantially to the production costs of the vinylaromatic monomer.
A particular problem arises in areas in the distillation apparatus where there is little vapor motion, such as adjacent the undersides of the seal pans. Monomer vapors condense against the cool undersides of the pans and form droplets of liquid monomer which may polymerize and solidify before they grow large enough to drop down into the underlying tray. Masses of unwanted polymeric material thus build up in the distillation apparatus. Liquid phase active inhibitors do not prevent such deposits because the condensing vapors do not carry these inhibitors with them. Even the use of vapor phase active inhibitors is not totally effective in supressing the formation of such deposits because the lack of vapor motion under the seal pans restricts the mixing of the inhibitor with the condensing vapors.
The continuing accumulation of undesired polymeric material thus requires that the distillation apparatus used to purify vinylaromatic monomers be periodically shut down and cleaned of the fouling polymer. As the polymer is typically a dense hard material, considerable difficulty may be encountered in cleaning the distillation apparatus. The need for periodic cleaning increases operating costs, and capital costs are also increased because additional distillation capacity must be constructed in order to compensate for the down time of the distillation apparatus.
Despite the efforts of the prior art, there remains a substantial need for improved methods and apparatus for inhibiting the formation of undesired polymeric residues in distillation apparatus used to purify vinylaromatic monomers.
OBJECTS OF THE INVENTION
Accordingly, it is an object of the present invention to provide an improved method and apparatus for inhibiting the formation of polymerized vinylaromatic compounds during distillative purification of a crude vinylaromatic monomer feed.
Another object of the present invention is to provide a method and apparatus for inhibiting the formation of polymerized vinylaromatic compounds which will not increase the need for expensive chemical inhibitors.
A further object of the present invention is to provide a method and apparatus for inhibiting the formation of polymerized vinylaromatic compounds which will permit distillation systems used to purify vinylaromatic monomers to be run for longer periods before shut-down for cleaning becomes necessary.
It is also an object of the present invention to provide method and apparatus for inhibiting the formation of polymerized vinylaromatic compounds in the areas under the seal pans of the distillation apparatus where there is little vapor motion.
Yet another object of the present invention is to provide a method and apparatus for inhibiting the formation of polymerized vinylaromatic compounds during distillative purification of a vinylaromatic monomer which will increase the yield of monomer.
An additional object of the present invention is to provide a method and apparatus for purifying a vinylaromatic monomer which will decrease the formation of undesired soluble and insoluble polymer byproducts.
A still further object of the present invention is to provide a method for distilling a vinylaromatic monomer which inhibits fouling of the distillation column and an apparatus for distilling a vinylaromatic monomer which is less prone to fouling.
It is also an object of the present invention to provide a method and apparatus for producing substantially pure vinylaromatic monomer which is more economical than prior art methods.
SUMMARY OF THE INVENTION
These and other objects of the invention are achieved by providing a method for controlling the formation of polymer accumulations on the undersides of the seal pans in a distillation column used for distillative purification of a vinylaromatic monomer comprising accumulating liquid phase material containing an effective polymerization inhibiting concentration of polymerization inhibitor in the seal pans, providing liquid pervious weep hole means through the seal pans, and allowing a controlled quantity of polymerization inhibitor-containing liquid phase material from the seal pans to seep through the weep hole means to the undersides of the seal pans.
The objects of the invention are further achieved by providing apparatus for controlling the formation of polymer accumulations on the undersides of the seal pans in a distillation column used for distillative purification of a vinylaromatic monomer comprising at least one distillation column containing a series of gas/liquid contact trays having seal pans associated therewith for providing a liquid seal between successive trays in the series; said seal pans being provided with liquid pervious weep hole means through the bottoms thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further explained with reference to the accompanying drawings wherein:
FIG. 1 is a schematic representation of a distillation system for purifying a crude vinylaromatic monomer;
FIG. 2 is a schematic sectional representation of a portion of a distillation column for purifying vinylaromatic monomer;
FIG. 3 is a photograph of the underside of a recycle distillation column seal pan provided with weep hole means according to the invention at the end of a vinyltoluene production run; and
FIG. 4 is a similar photograph of the underside of an adjacent seal pan not provided with weep hole means according to the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings, FIG. 1 shows schematically a distillation system for purifying crude vinylaromatic monomer. The illustrated system will be described in conjunction with the distillation of vinyltoluene, but it is understood that the distillation system and the invention are useful for purifying other vinylaromatic monomers such as styrene, alpha-methylstyrene, divinylbenzene and the like. It is considered within the skill of the art to adjust the operating parameters as necessary to adapt the system to other vinylaromatic monomers.
A crude vinyltoluene feed recovered from the dehydrogenation of ethyltoluene is condensed and introduced through line 2 into the intermediate portion of a recycle distillation column 4. Recycle column 4 is a conventional multi-tray distillation column containing a series of suitable vapor/liquid contact devices such as bubble cap trays, perforated trays, valve trays, etc. Either single path or parallel path columns may be utilized although the parallel distillation path design is preferred. Typically, the number of trays in recycle column 4 will range between 40 and 100. Preferably, at least about 72 trays are provided in the recycle column in order to facilitate proper separation of the constituents of the crude vinyltoluene feed mixture.
The recycle column is typically operated at temperatures ranging between about 65 and about 138 degrees C. and at absolute pressures ranging from about 0.013 to about 0.26 atmospheres (10 to 200 mm Hg). Preferably distillation temperatures in the recycle column lie between about 90 and about 115 degrees C. and the pressure is maintained between about 0.04 and about 0.15 atmospheres. A reboiler 6 is associated with distillation column 4 to provide the heat necessary to maintain distillation conditions in the column. Reboiler temperatures are maintained between about 90 and about 120 degrees C. by controlling the reboiler pressure between about 0.04 and about 0.50 atmospheres (30 to 400 mm Hg). A recycle overhead fraction comprising principally a mixture of lower boiling alkylaromatic compounds such as ethyltoluene, xylene and toluene, is withdrawn from the top of recycle column 4 through line 8.
The recycle bottoms fraction, comprising principally vinyltoluene admixed with higher boiling materials such as vinyltoluene oligomers, is withdrawn from the bottom of recycle column 4 through line 10 and introduced into the intermediate portion of finish distillation column 12. Finish column 12 is a multitray distillation column similar in design to recycle column 4. Finish column 12 typically contains between about 15 and about 30 trays. The finish column is operated at a temperature lying in the range from about 70 to about 100 degrees C. and at an absolute pressure lying in the range from about 0.01 to about 0.06 atmospheres. A reboiler 14 is associated with finish column 12 to provide the heat necessary to maintain appropriate distillation conditions in the finish column.
The finish column bottoms fraction, comprising principally tarry residues admixed with some residual vinyltoluene monomer, is withdrawn from the bottom of finish column 12 through line 16. The finish column overhead fraction withdrawn from column 12 through line 24 comprises substantially pure vinyltoluene.
In the illustrated distillation scheme, the recycle overhead fraction withdrawn from recycle column 4 through line 8 is introduced into an alkylbenzene distillation column 26. Alkylbenzene column 26 is also a conventional distillation column similar in design to recycle column 4, except that the alkylbenzene column typically contains 40 or fewer trays. The alkylbenzene column is operated at a temperature from about 125 to about 190 degrees C. and at an absolute pressure from about 0.9 to about 1.7 atmospheres. A reboiler 28 is associated with alkylbenzene column 26 to provide the heat necessary to maintain appropriate distillation conditions in the distillation column. An overhead fraction comprising low boiling aromatics such as xylene, toluene and/or benzene is withdrawn from the top of alkylbenzene column 26 through line 30. This fraction may be used as a solvent, or it may be conveyed to further reaction steps such as isomerization or alkylation. The alkylbenzene column bottoms fraction comprising principally the vinyltoluene precursor, ethyltoluene, is withdrawn from the bottom of alkylbenzene column 26 through line 32 and returned to the dehydrogenation reactor to produce additional vinyltoluene.
Generally, polymerization inhibitors are introduced into the vinyl aromatic monomer during the distillation. Preferred inhibitors include nitrated phenolic compounds such as dinitro-o-cresol, dinitro-p-cresol, m-nitro-p-cresol, dinitrophenol, N-nitroso-diphenylamine, 4-halo-3,5-dinitrotoluene, 3-nitro-2,5-cresotic acid and the like. Sulfur may also be used as an inhibitor, but its use is not preferred because the resulting sulfur-containing tarry residues have little economic value and are very difficult to dispose of. Mixtures of inhibitors may be used. A particularly preferred inhibitor comprises a mixture of N-nitroso-diphenylamine (NDPA) which is active primarily in the vapor phase and dinitro-p-cresol (DNPC) which is active primarily in the liquid phase.
The inhibitors may be introduced in any desired manner. Inhibitor from a source of inhibitor 34 may be introduced through line 36 into the crude vinyltoluene feed in line 2 prior to introduction of the feed into recycle column 4. Inhibitor from a source 38 may be introduced directly into recycle column 4 and/or finish column 12 through lines 40 and 42, respectively. It is also possible to add inhibitor to the reboilers.
The amount of inhibitor required depends upon the specific inhibitor used, but generally lies between about 50 and about 3000 ppm with respect to the vinyltoluene. Higher amounts may be utilized, but ordinarily little benefit is gained from the additional expenditure. In most cases, the inhibitor concentration will lie between about 200 and about 1000 ppm with respect to the vinyltoluene. Since the inhibitors are generally stable, the tarry residues recovered from the finish column usually contain appreciable amounts of inhibitor. The amount of fresh inhibitor required to be introduced into the distillation system may optionally be reduced by recycling a portion of the inhibitor-containing tarry residues back to recycle column 4 either by mixing the residue with the crude feed entering through line 2 or by introducing the residue directly into the recycle column.
FIG. 2 is a schematic partial sectional view of recycle distillation column 4 showing a portion of the distillation column wall 44 and three of the internal gas/liquid contact trays 46, 48 and 50, respectively. A seal pan 52 is shown under the downcomer area 54 of each tray. Supports underlying the seal pans are designated by reference numeral 56. Liquid phase material collects at the bottom of downcomer 54 in each downcomer seal pan 52. A series of weep holes 58 are provided through the bottoms of downcomer seal pans 52. Typically the weep hole means take the form of a series of small circular apertures, but it is understood that it is not essential that the weep holes be round. The size of the weep holes is critical. If the holes are too small, liquid phase material will not flow down through the holes. The holes will merely fill with liquid which will remain in the holes until it polymerizes and plugs the holes. If the holes are too large, then liquid will flow too rapidly through the holes and too much liquid will bypass the active area of the tray, thereby adversely affecting the distillation efficiency of the column. Similar disadvantages accrue if there are too many weep holes through the bottom of the tray. If the weep holes are too large or if there are too many weep holes, it is even possible that the liquid seal on the tray may be lost. Another disadvantage of holes which are too large is the fact that vapor from the underlying tray will pass through the holes and cause foaming in the downcomer above the seal pan. This can result in liquid flooding of the column and reduced column capacity.
The weep holes should be sufficiently large that liquid phase material will seep steadily through the holes to the underside of the seal pan, but they should not be so large that the liquid can run through in a steady stream. It has been found that the weep holes should be not less that about 2 mm in diameter nor more than about 10 mm in diameter. Preferably the weep holes will be between about 4 mm and about 8 mm in diameter. The spacing between adjacent weep holes should be not less than about 50 mm nor more than about 150 mm. Desirably the distance between adjacent weep holes will be from about 4 to about 25 times the diameter of the holes. It is particularly desirable that weep holes be positioned adjacent the column wall and next to the supports underlying the seal pans as these are areas where polymer accumulations are especially likely to form.
In the operation of the distillation column, vinyltoluene vapors designated by arrows 60 rise from each tray through the column toward the tray above. Some of the vapors contact the cool bottoms of seal pans 52 where they condense. Eventually, the droplets of condensed vapor will become large enough to fall back onto the underlying trays. However, problems occur if the condensed vinyltoluene polymerizes before the droplets become large enough to fall back to the underlying tray. The polymerized vinyltoluene will gradually build up on the undersides of the seal pans until it is necessary to take the distillation column out of service for cleaning.
During normal operation of the distillation column, liquid phase material accumulates in the seal pans at the bottoms of the downcomers. This liquid phase material will contain some of the polymerization inhibitor introduced into the distillation column which prevents the liquid phase material in the seal pans from polymerizing.
In the invention, a controlled amount of the liquid phase material from the seal pans is allowed to seep through weep holes 58 to the undersides of the seal pans. The amount of liquid which seeps through the weep holes is controlled by the number and size of the holes. Some polymerization inhibitor passes through the weep holes with the seeping liquid phase material. This inhibitor material mixes with the condensing vinyltoluene on the underside of the seal pan and serves to inhibit polymerization of the condensing vinyltoluene. Moreover, the seeping liquid phase material assists in washing the condensed vinyltoluene from the bottom of the seal pan back down to the underlying tray. Accumulation of a mass of polymerized vinyltoluene on the undersides of the seal pans is thus prevented.
It is not necessary that every seal pan in the distillation column be provided with weep hole means. If desired, only selected trays under which polymer accumulations are most likely to form may be provided with weep hole means.
Further details of the invention will be apparent from a consideration of the following examples.
EXAMPLE 1
A series of approximately 1.5 mm (1/16th inch) diameter weep holes was provided through the bottom of the seal pan associated with tray 29 of a 72 tray recycle distillation column used for distillative purification of vinyltoluene. The column was then placed in service in the distillation of vinytoluene. Dinitro-o-cresol at a concentration of 500 ppm with respect to the vinyltoluene was used as a polymerization inhibitor. Column temperatures were maintained at 105±7 degrees C. After 6 weeks, the column was taken out of service. The seal pan provided with weep holes and the seal pan of the next higher tray were examined for polymer accumulations. It was found that the weep holes were plugged with polymeric material and that the polymer accumulation under the seal pan of tray 29 was only slightly less than that under the seal pan of tray 30. This test shows that the weep holes must be greater in size than 1.5 mm.
EXAMPLE 2
The distillation column of Example 1 was cleaned, and the weep holes in tray 29 were enlarged to a diameter of 6.3 mm (1/4th inch). The distillation column was then placed back in service. After 60 days operation, the column was again taken out of service and the undersides of the trays were inspected. As can be from FIG. 3, only a very slight polymer accumulation was found under the seal pan of tray 29 which had been provided with the weep holes of the invention. In contrast thereto, a substantial polymer accumulation was again found under the seal pan of tray 30 as can be seen from FIG. 4. This example shows that the weep holes of the invention, when properly sized, are effective in preventing the formation of undesired polymer accumulations on the undersides of the seal pans.
The foregoing description and examples have been set forth merely for purposes of exemplification and are not intended as limiting. Since modifications of the disclosed embodiments within the scope and spirit of the invention may occur to persons skilled in the art, the scope of the invention is to be limited solely by the scope of the appended claims: | A method for controlling the formation of polymer accumulations in a distillation column comprising accumulating liquid phase material containing a polymerization inhibitor in a seal pan; providing the seal pan with liquid-pervious weep hole means through the bottom of the pan and allowing a controlled quantity of polymerization inhibitor-containing liquid phase material to seep through the weep hole means to the underside of the seal pan; and apparatus useful for practicing the disclosed method. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 09/967,893 filed, Sep. 27, 2001, the disclosure of which is incorporated herein by reference, which claims the benefit of prior U.S. provisional application 60/280,684, filed Mar. 30, 2001.
BACKGROUND
The invention relates to an Internet security system. The growth of the Internet and high-traffic web sites that require high performance and high bandwidth networks have resulted in an increased number of so-called service providers, including Internet data centers, application service and security service providers. A service provider, including an Internet data center, provides network resources, one or more dedicated servers and, in some cases, physical space, to host services for a number of customers, usually for a fee. Conventionally, service providers must install and configure one or more dedicated servers to support each customer and will likely require complex networks to manage separate services for the service provider's customer base. In this environment, the customer typically has some administrative control of the servers and control of the content residing on the servers. An Internet data center typically provides the network, network access, hardware, software and infrastructure needed to power the service, including web site, managed security, and so on.
An exemplary view of the organization of a conventional Internet data center is shown in FIG. 1 . In the present example, the Internet data center ( 100 ) has a number of customers A, B, C, D. The Internet data center ( 100 ) shown in FIG. 1 is set up for four customers only, while in reality a data center may host hundreds or potentially thousands of users. Each customer has one or more dedicated servers ( 105 ), a dedicated firewall ( 110 ) and one or more switches ( 115 ) that are all connected and form a subnet ( 120 ) for that particular customer. The subnets ( 120 ) are coupled together in the core switch fabric ( 125 ), which in turn forms an interface to the Internet.
The conventional model for organizing an Internet data center requires that a separate firewall device be deployed every time a new customer joins the Internet data center, which may require network re-configuration, and be a labor intensive and costly task. In this environment, the staff at the Internet data center must separately configure, upgrade, manage and support each firewall device separately. The conventional way for organizing Internet data centers also requires a heavy need for physical rack space to accommodate the physical installation of separate firewall and other networking devices upon which the provider's services are hosted. As a result of the large amount of separate equipment, the wiring and related switching and routing infrastructure becomes complex. If a firewall fails, it will be costly to repair or replace and the down time the client experiences before his or her firewall has been repaired or replaced may be considerable. The down time can be reduced if redundant boxes are provided, but this solution leads in turn to increased cost, space, maintenance and wiring problems, and is therefore not a desirable solution
SUMMARY
In general, in one aspect, this invention provides methods and apparatus, including computer program products, implementing and using techniques for processing data packets transferred over a network. The data processing system includes a firewall engine that can receive a set of firewall policies and apply the firewall policies to a data packet, an authentication engine that can receive a set of authentication policies and authenticate a data packet in accordance with the authentication policies, one or more virtual private networks that each have an associated destination address and policies and a controller that can detect an incoming data packet, examine the incoming data packet for a virtual private network destination address and identify the policies associated with the virtual private network destination. If the policies include firewall policies, then the controller can call the firewall engine and apply the set of firewall policies corresponding to the virtual private network destination to the data packet. If the policies include authentication policies, then the controller can call the authentication engine and apply the set of authentication policies corresponding to the virtual private network destination to the data packet. The controller can also route the data packet to the virtual private network containing the data packet's destination address.
Advantageous implementations can include one or more of the following features. The controller can route the data packet by reading a set of entries in a private routing table and outputting the data packet to its virtual private network destination address using a routing protocol associated with the packet's virtual private network destination address.
In general, in one aspect, this invention provides methods and apparatus, including computer program products, implementing and using techniques for processing a data packet in a packet forwarding device. A data packet is received and a virtual local area network destination is determined for the received data packet, including identifying a set of rules that are associated s with the virtual local area network destination. The set of rules is applied to the data packet and if a virtual local area network destination has been determined for the received data packet, the data packet is output to its virtual local area network destination, using the result from the application of the rules. If a virtual local area network destination has not been determined for the received data packet, the data packet is dropped.
Advantageous implementations can include one or more of the following features. A traffic policy can be applied to the received data packet, the traffic policy being associated with the packet forwarding device and applied to all data packets processed by the packet forwarding device. Determining a virtual local area network destination can include extracting layer information from the data packet and using the extracted layer information to determine a virtual local area network destination for the data packet. The layer information can include layer 2 information, layer 3 information, layer 4 information and layer 7 information. Applying the rules to the data packet can include shaping the data packet based on the virtual local area network destination and discarding the data packet if no virtual local area network destination is determined. Shaping the data packet can include attaching a digital address tag to the data packet, the digital address tag identifying a virtual local area network destination. The digital address tag can be read and the data packet can be output using the digital address tag content.
Applying the rules to the data packet can include applying a set of rules selected from network address translation, mobile internet protocol, virtual internet protocol, user authentication and URL blocking. Applying the rules to the data packet can include applying a set of policies selected from incoming policies and outgoing policies for a virtual local area network destination. Entries from one or more of a global address book, a private address book, and a global service book can be received and applying the rules to the data packet can include using the retrieved entries.
Available resources for outputting the data packet to the virtual private network destination can be determined, wherein the resources are definable by a user. Outputting the data packet can include outputting the data packet to a determined virtual private network destination in accordance with the determined available resources. Applying the rules to the data packet can include applying a set of virtual tunneling rules for a virtual local area network destination, whre the tunneling rules are selected from PPTP, L2TP and IPSec tunneling protocols. Outputting the data packet can include reading a set of entries in a private routing table and if a virtual local area network destination has been determined for the received data packet, outputting the data packet to its virtual local area network destination using a routing protocol for the packet's virtual local area network destination. A set of rules configured by a user can be received.
In general, in one aspect, this invention provides methods and apparatus, including computer program products, implementing and using techniques for screening data packets transferred over a network. A connection to one or more virtual local area networks is established. A set of firewall configuration settings are associated with each of the one or more virtual local area networks. An incoming data packet is received. The incoming data packet is screened in accordance with a set of firewall configuration settings and the screened data packet is output to a particular virtual local area network among the one or more virtual local area networks, based on the result of the screening.
In general, in one aspect, this invention provides methods and apparatus, including computer program products, implementing and using techniques for transferring packets of data. One or more packet processing engines can receive an incoming packet of data, apply a global traffic policy to the incoming packet, classify the incoming packet including determining a virtual local area network destination, shape the incoming packet based on the virtual local area network destination and output the shaped packet.
Advantageous implementations can include one or more of the following features. One or more switches can be connected to the packet processing engine by a trunk cable to receive the shaped packet from the packet processing engine through the trunk cable, determine a destination device to which the shaped packet is to be routed and switch the shaped packet to a communication link that is connected to the destination device. The trunk cable can be a VLAN cable. A first packet processing engine of the one or more packet processing engines can be connected to a first switch of the one or more switches, and cross connected to at least a second switch of the one or more switches and a second packet processing engine of the one or more packet processing engines can be connected to the second switch of the one or more switches and cross connected to at least the first switch of the one or more switches.
Each of the first and second switches can connect to one or more communication links, each communication link representing a virtual local area network destination. A trunk cable can connect a switch and a packet processing engine. One or more virtual local area networks (VLANs) can be connected to the one or more switches via a communication link dedicated for the virtual local area network. Outputting the packet can include outputting the shaped packet to its virtual local area network destination through a destination port on the packet processing engine, the destination port connecting the packet processing engine via a communication link to a destination device.
One or more virtual local area networks (VLANs) can be connected to a destination port on the packet processing engine via a communication link dedicated for the virtual local area network. Each packet processing engine can perform one or more functions that are configurable for each virtual local area network.
In general, in one aspect, this invention provides methods and apparatus, including computer program products, implementing and using techniques for providing a security system including security system resources including firewall services and a controller that can partition the security system resources into a plurality of separate security domains. Each security domain can be configurable to enforce one or more policies relating to a specific subsystem, and to allocate security system resources to the one or more security domains.
Advantageous implementations can include one or more of the following features. The security system can allocate security system resources to a specific subsystem. The specific subsystem can be a computer network. The specific subsystem can be a device connected to a computer network. Each security domain can include a user interface for viewing and modifying a set of policies relating to a specific subsystem. The security system resources can include authentication services. The security system resources can include virtual private network (VPN) services. The security system resources can include traffic management services. The security system resources can include encryption services. The security system resources can include one or more of administrative tools, logging, counting, alarming and notification facilities, and resources for setting up additional subsystems.
A management device can provide a service domain, the service domain being configurable to enforce one or more policies for all security domains. The management device can include a user interface for viewing, adding and modifying any set of policies associated with any specific subsystem and the set of policies associated with the service domain. The service domain can include a global address book. Each set of security domain policies can include one or more policies for incoming data packets, policies for outgoing packets, policies for virtual tunneling, authentication policies, traffic regulating policies and firewall policies. The policies for virtual tunneling can be selected from the group consisting of PPTP, L2TP and IPSec tunneling protocols. One or more of the security domains can include a unique address book.
The invention can be implemented to realize one or more of the following advantages. A single security device can be used to manage security for multiple customers, Each customer has their own unique security domain with an address book and policies for management of content. Each domain is separately administrated. One customer's policies do not interfere with the other customers' policies. Additionally, attacks on one customer's domain will not have any influence on the functionality of other domains. To each customer, the firewall and any virtual private networks (VPNs) appear to be hosted on a discrete device, just like the conventional systems. For an Internet data center that employs the Internet security system in accordance with the invention, a number of benefits may result. Instead of upgrading and managing one device for each customer, a single device can be upgraded and managed for several customers. Less rack space will be required, since fewer devices are necessary, and as a consequence, the wiring scheme will be less complicated. The cost of deployment will be lower, the network complexity and requirements will be reduced, and higher performance throughput will be possible,
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features and advantages of the invention will become apparent from the description, the drawings, and the claims.
DESCRIPTION OF DRAWINGS
FIG. 1 is a schematic view of a prior art security system configuration for an Internet data center.
FIG. 2 is a schematic view of an Internet security system in accordance with the invention.
FIG. 3 is a schematic view of an Internet security system in accordance with an alternative implementation of the invention.
FIG. 4 is a schematic view of an Internet security system in accordance with another alternative implementation of the invention.
FIG. 5 is a flowchart showing a data packet processing method in accordance with the invention.
FIG. 6 is a flowchart detailing one implementation of the packet classification step in FIG. 5 .
FIG. 7 is a flowchart detailing one implementation of the packet classification step in FIG. 5 .
FIG. 8 is a flowchart detailing a alternative implementation of the packet classification step in FIG. 5 .
FIG. 9 is a schematic block diagram showing a more detailed view of the security device in FIG. 3 .
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
An Internet security system in accordance with the invention provides a multi-customer, multi-domain architecture that allows service providers, such as Internet data centers, application infrastructure providers and metropolitan area network providers to manage the security needs of multiple customers through one centralized system. The inventive Internet security system also allows service provider and end user customers to create and manage separate security domains, each domain acting as a stand alone system and having its own set of policies. The inventive Internet security system accomplishes this through unique architecture and software features that can be referred to as Virtual Systems. The Internet security system will be described by way of example. Three different exemplary architectures will be described with reference to FIGS. 2-4 . After the architectural system description of each implementation, the data flow through the system will be described. Finally, the user interface and a number of customizable functions of the Internet security system will be presented.
Internet Security System Using Virtual Local Area Networks
As shown in FIG. 2 , the Internet security system ( 200 ) in accordance with one implementation of the invention includes a first 100/1000 router switch ( 205 ) that connects a firewall device ( 210 ) to the Internet ( 215 ). The firewall device ( 210 ) acts as a common firewall for all the customers, and can be separately configured to fit each customer's policies and security needs. How the separate configurations are done will be explained in further detail below. On the secure side of the firewall device ( 210 ) is a Virtual Local Area Network (VLAN) trunk ( 220 ) that carries all packets to a second 100/1000 switch ( 225 ). A VLAN is a Layer 2 multiplexing technique that allows several streams of data to share the same physical medium, such as a trunk cable, while enjoying total segregation. The second switch ( 225 ) directs the packets on private links to the different customers' servers ( 230 ) through a 10/100 switch ( 235 ) for each customer.
An incoming data packet from the Internet ( 215 ) first passes the router switch ( 205 ) and enters the firewall device ( 210 ). The firewall device ( 210 ) determines what VLAN the packet is intended for and attaches a VLAN tag to the packet. In one implementation, the tag that is used is a 802.1Q tag. The 802.1Q VLAN tag requires 12 bits in the Ethernet packet header to hold the tag, and is defined in the 802.3ac Ethernet frame format standard ratified in 1998. The 802.3ac Ethernet frame format standard is supported by most backbone switches fabricated since the ratification of the standard. There are two ways to attach a tag to a data packet; implicit tagging and explicit tagging. The implicit tagging method assigns a tag to untagged data packets, typically based on which port the data packet came from. The implicit tagging method allows traffic coming from devices not supporting VLAN tagging to be implicitly mapped into different VLANs. The explicit tagging method requires that each data packet be tagged with the VLAN to which the data packet belongs. The explicit tagging method allows traffic coming from VLAN-aware devices to explicitly signal VLAN membership.
The packet then continues on VLAN trunk ( 220 ) to the VLAN switch ( 225 ), where the tag attached to the packet by the firewall device ( 210 ) is read. Based on the VLAN tag, the packet is routed by the VLAN switch ( 225 ) to the appropriate switch ( 235 ) and server ( 230 ). The operation of the firewall device ( 210 ) will be described in more detail below.
Internet Security System Using Port-Based Virtual Local Area Networks
Another implementation of the invention is shown in FIG. 3 , which shows essentially the same architecture as shown for the Internet security system in FIG. 2 . The difference is that the firewall device ( 210 ) has been replaced with a firewall device ( 305 ) with port-based VLAN. From each port in the firewall with the port based VLAN, there is a private link ( 310 ) to each customer, switch ( 315 ) and server ( 320 ). The system ( 300 ) does not include the VLAN trunk or the second 100/1000 switch of the Internet security system implementation shown in FIG. 2 .
An incoming data packet from the Internet ( 325 ) first passes the router switch ( 330 ) and enters the firewall device ( 305 ). The firewall device ( 305 ) determines what system the packet is intended for. Instead of attaching a VLAN tag to the packet, the firewall device directs the packet to the proper dedicated port for the VLAN. The packet then continues on the selected private link ( 310 ) to the switch ( 315 ) and server ( 320 ) for the selected VLAN.
FIG. 9 shows a more detailed view of the Internet security system of FIG. 3 , and in particular of the firewall device ( 305 ). The firewall device ( 305 ) includes functionality not conventionally included in a firewall and can therefore be referred to more generally as a security system or a data processing system. The security system has a number of engines, such as a firewall engine ( 905 ), an authentication engine ( 910 ), and optionally other engines. A user interface ( 985 ) is also provided in the security system, which allows a user to set different policies for the different engines. The different engines communicate with each other through a bus ( 920 ). A user can set firewall policies for the firewall, such as incoming policies and outgoing policies for a virtual local area network destination, and authentication policies for the authentication engine, such as network address translation, mobile Internet protocol, virtual Internet protocol, user authentication and URL blocking.
When a packet comes in, a controller ( 915 ) detects the packet. The controller is connected to the bus ( 920 ) and can communicate with the engines. Also connected to the bus ( 920 ) is a set of virtual private networks ( 925 - 940 ), that each are connected to a network, optionally through one or more switches ( 315 ). The exemplary networks shown in FIG. 9 include two DMZs (Demilitarized Zones) ( 965 , 970 ), an extranet ( 975 ) and a general population net ( 980 ). Each of the virtual private networks (VPNs), has an associated destination address and policies. After the packet has been detected by the controller ( 915 ), the controller ( 915 ) examines the data packet for a virtual private network destination address and identifies the policies that are associated with the virtual private network destination. If the policies include firewall policies, the controller ( 915 ) calls the firewall engine ( 905 ), which applies the set of firewall policies corresponding to the virtual private network destination to the data packet. If the policies include authentication policies, the controller ( 915 ) calls the authentication engine ( 910 ), which applies the set of authentication policies corresponding to the virtual private network destination to the data packet. After the respective engine has applied the policies, the data packet is routed to the virtual private network corresponding to the data packet's destination address. How the incoming data packet is examined will be described in greater detail below.
The security system as a whole thus has a finite amount of security system resources, including firewall and authentication services. The controller partitions the security system resources into a number of separate security domains, each security domain being related to a private or public network. Each security domain is configurable to enforce one or more policies relating to a specific subsystem or network. The controller allocates security system resources to the one or more security domains based on the needs of the respective security domain, by calling the different engines, as described above. Instead of the static resource allocation in conventional Internet security systems with one security device or firewall per client, as was described in the background section above, the inventive Internet security system provides dynamic resource allocation on a as needed basis for the different virtual private networks and associated systems.
The security system resources can include a wide range of resources, such as authentication services, virtual private network (VPN) services, include traffic management services, encryption services, administrative tools, logging, counting, alarming and notification facilities, and resources for setting up additional subsystems.
Internet Security System Using Virtual Local Area Networks with High Availability
Yet another implementation of the invention is shown in FIG. 4 , which shows an Internet security system architecture ( 400 ) similar to that shown in FIG. 2 . However, in order to provide the ability to accommodate more traffic and to provide higher availability in the event of equipment failure, the system provides dual firewalls ( 405 , 410 ) and dual second switches ( 415 , 420 ). The first switches have been replaced with switch/routers ( 425 , 430 ) that can direct incoming traffic to either firewall ( 405 , 410 ). Each firewall is connected to both second switches ( 415 , 420 ) through VLAN trunks ( 435 ), and each of the second switches is connected to all the customer switches ( 440 ) by private links ( 445 ). The cross connection scheme ensures that an alternate route for data packages will be available, even in the event of component failure, and a high availability is thereby ensured.
An incoming data packet from the Internet arrives at one of the router switches ( 425 , 430 ). The router switch decides what firewall device ( 405 , 410 ) to send the packet to, based on which firewall device currently has most available capacity and sends the packet to that firewall device. Just like the above-described implementation shown in FIG. 2 , the firewall device ( 405 , 410 ) determines what VLAN the packet is intended for, and attaches a VLAN tag to the packet. The packet then continues on VLAN trunk ( 435 ) to the VLAN switch ( 415 , 420 ) with the most available capacity, where the tag attached to the packet by the firewall device ( 405 , 410 ) is read. Based on the VLAN tag, the packet is routed by the VLAN switch ( 415 , 420 ) through a private link ( 445 ) to the appropriate switch ( 440 ) and server ( 450 ).
Packet Classification and Context Partition
The following example describes a process for classifying and sending out an incoming packet to the appropriate virtual system using the firewall device in the Internet security system in accordance with the invention. As shown in FIG. 5 , a process ( 500 ) for classifying and sending out an incoming data packet begins with receiving a data packet ( 505 ). In the present example, the data packet is assumed to come from a trusted host. Data packets that are received from an untrusted host will be treated somewhat differently, which will be described below.
Once the data packet has been received, the layer 2 (L2) information and the layer 3 (L3) information is extracted from the packet ( 510 ). The L2 information includes: Interface Number and VLAN ID. The L3 information includes IP head or information.
After the L2 and L3 information has been extracted, one or more global traffic policies are applied to the packet ( 515 ). The global traffic policies apply to all virtual system domains in the Internet security system.
When the global traffic policies have been applied, the packet goes through a classification ( 520 ) to find a Virtual System Context. The virtual system context is an object containing all the configuration parameters for the virtual system to which the packet is destined. The packet classification is based a combination of the interface, VLAN ID and/or L3/L4 (that is, TCP/UDP port) information. In a simple configuration, Interface and VLAN ID will be sufficient, while in a more complicated configuration, all the information listed above is necessary to locate the right context. The packet classification step is essential for the method and will be described in further detail below after the overall data packet processing procedure has been described.
The procedure then checks if a virtual system context has been found ( 525 ). If no virtual system context can be found, the packet is dropped and the event is logged ( 530 ). If a virtual system context has been found, the packet will be subjected to firewall/VPN/traffic shaping processing ( 535 ), in the same way as the packet would be processed on a stand-alone device. After the firewall/VPN/traffic shaping processing the procedure transforms the packet into an egress packet, and the L2 information is encapsulated ( 540 ) before the packet is transmitted out through a designated interface port to the proper Virtual private network, which completes the procedure.
If the incoming packet comes from an untrusted interface, the processing is somewhat different than when the packet originates at a trusted interface. The different processing is necessary because an untrusted interface may be shared among several virtual systems. Therefore, the packet classification step ( 520 ) will, optionally, use more information, such as tunnel identifications for protocols such as IPSEC, L2TP. When a tunnel has been identified, the virtual system context can be identified, and the packet can pass to the Firewall/VPN/Traffic shaping step ( 535 ).
For non-tunnel traffic, a policy-based and session-based look-up table may be used to identify a virtual system context for the traffic from an untrusted interface. In the packet classification step ( 520 ), the packet will be subject to a global policy in order to identify if there is a session anywhere in the whole security system that matches with the packet. If such a session exists, the context point in the session record informs the security system about which virtual system context is the correct one. If there is no session match, but there is a policy that matches the packet, then that policy will point to the proper virtual system context for continued processing.
The classification step ( 520 ) described above determines to which virtual system the incoming data packet is destined. The classification step ( 520 ) will now be described in more detail with reference to FIGS. 6-8 that show in greater what happens to the data packet during the classification. Conceptually, the Internet security system in accordance with the invention can be viewed as processes in an operating system, the primary difference being that processes in an operating system are event driven, while the Internet security system is packet driven. When the Internet security system receives an incoming data packet, the system needs to classify the packet based on information contained in the packet and on the policies that have been configured for the system. When the packet has been classified, the virtual system context to which the packet belongs is found, and the packet is passed to the associated virtual system context for further processing. From the point of view of the virtual system, the packet appears to have originated in one of the virtual interfaces configured for the virtual system.
The classification of the incoming packet is made based on information from layer 2 (L2), layer 3 (L3), layer 4 (L4) and layer 7 (L7) information. The classification may be made based on one or more layers. For example, in a simple configuration, a virtual system using VLAN to separate different secure domains, the VLAN ID in the VLAN Ethernet packet is sufficient to classify the packet and identify the destination virtual system context. This is referred to as simple classification. An exemplary process for simple classification is shown in FIG. 6 , where the L2 information is extracted ( 605 ), the virtual interface table is searched with the VLAN ID and the interface number ( 610 ). Based on the VLAN ID and the interface number, the process can determine whether a virtual system context has been found ( 615 ). If no virtual system context can be found, then the simple classification is not sufficient ( 620 ), and if a virtual system context can be found, then the simple classification is sufficient ( 625 ).
In an Internet security system with shared outside identity, a session database is used along with L2, L3 and L4 information to identify the correct virtual system. This is referred to as multi-layer classification. A process for multi-layer classification is shown in FIG. 7 , where the L2 information ( 705 ), the L3 information ( 710 ) and the L4 information is extracted ( 715 ), before the session database is searched ( 720 ). Based on the L2, L3 and L4 information and the information in the session database, the process can determine whether a virtual system context has been found ( 725 ). If no virtual system context can be found, then the multi-layer classification is not sufficient ( 730 ), and if a virtual system context can be found, then the multi-layer classification is sufficient ( 735 ).
When complicated applications with dynamic port session (such as, FTP, RPC, H.323, and so on) are involved, a dynamic session database, along with L2, L3, L4, and L7 (application layer) information are used to identify the virtual system context. This is referred to as L7 classification. A process for L7 classification is shown in FIG. 8 , where the L2 ( 805 ), the L3 ( 810 ), the L4 ( 815 ) and the L7 information is extracted ( 820 ) before the dynamic session database is searched ( 825 ). Based on the L2, L3, L4, and L7 information and the dynamic session database, the process can determine whether a virtual system context has been found ( 830 ). If no virtual system context can be found, then the simple classification is not sufficient ( 835 ), and if a virtual system context can be found, then the simple classification is sufficient ( 840 ). Each of the simple, multi-layer or L7 classification can be performed by itself, or the processes can be performed in series, going from the simple classification, through the multi-layer classification to the L7 classification until the packet has been classified and a virtual system context has been identified.
The virtual systems are created through configuration of the Internet security system in real time or at start up with a saved configuration script. A system administrator creates virtual system context under a root privilege, and assigns certain attributes to the context. The system resources are now partitioned to support the new virtual system. A virtual system user can then log in to the system and will only see his or her virtual system, as if the user owned the whole system. A virtual system owner then can add, change and remove different attributes on the context. Once submitted, all attributes will be saved as configuration data for the Internet security system and be used to partition resources, change the global classification policy, and so on. How the Internet security system and individual virtual systems can be configured will be discussed in further detail below.
Configuring an Internet Security System
The description will now continue with an example showing how to configure an Internet security system in accordance with the invention, and showing three different examples of the user interfaces: one for a root level configuration, one where a root user creates a virtual system and adds configuration data, and one where a virtual system user logs in to a virtual system and changes configuration data.
First, a root user (that is, a system administrator for the whole Internet security system) with the user name “Netscreen” logs in to the system by entering the username and a password:
login: Netscreen
password:
ns1000->
The root user is now logged on and can access the root level interface configuration to view the different user interfaces that are present on the system. The command ‘get interface,’ for example, yields the following five interfaces, shown in Table 1 below.
TABLE 1
User interfaces present on the Internet Security System
Name
Stat
IP Address
Subnet Mask
MAC/VLAN/VSYS
Manage IP
Trust
Down
10.1.1.250
255.255.255.0
0010.dbf.1000
0.0.0.0
Trust/1
Down
11.1.1.250
255.255.255.0
Nat/trust.100(100)/NULL
0.0.0.0
Untrust
Down
192.1.1.250
255.255.255.0
0010.dbf0.1001
Mgt
Up
0.0.0.0
0.0.0.0
0010.dbf0.1002
192.168.1.1
Ha
Down
0.0.0.0
0.0.0.0
0010.dbf0.1004
192.168.1.1
The root user can view the root level address entry configuration with the command ‘get address’ which yields the trusted, untrusted, and virtual addresses shown in Table 2 below:
TABLE 2
Trusted, Untrusted, and Virtual Addresses
Name
Address
Netmask
Flag
Comments
Trusted Individual Addresses:
Inside
0.0.0.0
0.0.0.0
02
All trusted
Any
addr.
T11net
11.1.1.0
255.255.255.0
00
Untrusted Individual addresses:
Outside
0.0.0.0
0.0.0.0
03
All
Any
Untrusted
Addr
Dial-Up
255.255.255.255
255.255.255.255
03
Dial-Up
VPN
VPN Addr
u-199net
199.1.1.0
255.255.255.0
01
Virtual Individual Addresses:
All
0.0.0.0
0.0.0.0
12
All Virtual
Virtual
Addr
Ips
The root user can view the Virtual Private Network configuration by typing the command ‘get vpn’ which yields the virtual private network configuration in Table 3 below. Here, there is only one VPN setting for the system.
TABLE 3
VPN systems for the Internet Security System
Local
Remote
Name
Gateway
SPI
SPI
Algorithm
Monitor
m-t11-
192.2.1.250
00001234
00004321
Esp:3des/null
Off
u199
Total manual VPN: 1
To view the access policy configuration, the root user types the command ‘get policy’ which yields the three policies shown in Table 4 below for the root system.
TABLE 4
Policies for the root system in the Internet Security System
PID
Direction
Source
Destination
Service
Action
STLC
0
Outgoing
T-11net
u-199net
Any
Tunnel
—
1
Incoming
U-199net
t-11net
Any
Tunnel
—
2
Inside
Any
Outside
Any
Permit
—
The description will now continue with explaining how the root user can create a new virtual system named “marketing” and configure that system. The root user first adds the virtual system “marketing” to the Internet security system.
ns1000-> set vsys marketing
The root user then adds configuration data to the newly created system “marketing” by first adding two virtual interfaces for the “marketing” system. Note how the prompt has changed to indicate that the root user is working in the “marketing ” system.
ns1000(marketing)-> set interface trust/200 ip 20.1.1.250 255.255.255.0 tag 200
ns1000(marketing)-> set interface untrust/200 ip 193.1.1.250 255.255.255.0 tag 200
The next configuration to update is to add a virtual system private address entry to the “marketing” system.
ns1000(marketing)-> set address trust t-20net 20.1.1.64 255.255.255.128
The root user then adds a MIP attribute to the private virtual interface, as well as two incoming/outgoing policies.
ns1000(marketing)-> set interface untrust/200 mip 193.1.1.241 host 20.1.1.40
ns1000(marketing)-> set policy incoming out-any mip(193.1.1.241) http permit
ns1000(marketing)-> set policy outgoing t-20net out-any any permit auth
Next, the root user can verify the interface configuration settings by typing the command ‘get interface’. As shown above, the ‘get interface’ command yields the virtual interfaces for the current system. Since the current system is the “marketing” system, the root user will only see two virtual interfaces crated above, as shown in Table 5 below.
TABLE 5
Virtual interfaces for the “marketing” virtual system
Manage
Name
Stat
IP Address
Subnet Mask
MAC/VLAN/VSYS
IP
Trust/200
Down
20.1.1.250
255.255.255.0
Nat/trust.200(200)/marketing
Trust/200
Down
193.1.1.250
255.255.255.0
Route/untrust.200(200)/
marketing
As described above, the root user can see the virtual system address configuration for the “marketing” system by typing the command ‘get address,’ which yields the address entries shown in Table 6 below.
TABLE 6
Address entries for the “marketing” system
Name
Address
Netmask
Flag
Comments
Trusted Individual Addresses:
Inside
0.0.0.0
0.0.0.0
02
All trusted
Any
addresses
T-20net
20.1.1.64
255.255.255.128
00
Untrusted Individual addresses:
Outside
0.0.0.0
0.0.0.0
03
All Untrusted
Any
Addresses
Dial-Up
255.255.255.255
255.255.255.255
03
Dial-Up VPN
VPN
Addresses
Virtual Individual Addresses:
All
0.0.0.0
0.0.0.0
12
All Virtual
Virtual
Addresses
Ips
MIP
193.1.1.241
255.255.255.255
10
Untrust/200
The user can now retrieve the policies for the “marketing” system by typing the command ‘get policy’ at the prompt. The get policy command yields the following two policies for the “marketing” system, shown in Table 7 below.
TABLE 7
Policies for the “marketing” system
PID
Direction
Source
Destination
Service
Action
STLC
0
Incoming
Outside
MIP
HTTP
Permit
—
Any
(193.1.1.124)
1
Outgoing
t-20net
Outside Any
Any
Permit-
—
Auth
The configuration file for the “marketing” system virtual system can be obtained by typing ‘get config’ which yields:
Total Config size 1503:
set vsys “marketing”
set vsys-id 1
set auth type 0
set auth timeout 10
set admin name “vsys_marketing”
set admin password nIxrDlr7BzZBcq/LyshENtLt9sLGFn
set interface trust/200 ip 20.1.1.250 255.255.255.0 tag 200
set interface untrust/200 ip 193.1.1.250 255.255.255.0 tag 200
set interface untrust/200 mip 193.1.1.241 host 20.1.1.40 netmask 255.255.255.255
set address trust “t-20net” 20.1.1.64 255.255.255.128
set policy id 0 incoming “Outside Any” “MIP(193.1.1.241)” “HTTP” Permit
set policy id 1 outgoing “t-20net” “Outside Any” “ANY” Permit Auth
exit
The root user has now created a virtual system, configured the system, and verified that all the settings are correct. He or she then exits the marketing system, saves the new configuration and the prompt returns to the root level.
ns1000(marketing)-> exit
Configuration modified, save? [y]/n y
Save System Configuration . . . Done
ns1000>
The current Internet security system settings can now be viewed by the root user by typing ‘get vsys’, which yields the settings shown in Table 8 below. As can be seen the Internet security system now has a marketing system and a sales system. The marketing system has one sub-interface, while the sales system has a trusted and an untrusted interface.
TABLE 8
Internet security system settings
Sub-
Name
ID
interface
VLAN
IP/Netmask
Marketing
1
Trust/200
Trust.200
20.1.1.250/
255.255.255.0
Sales
2
Trust/300
Trust.300
30.1.1.250/
255.255.255.0
Untrust/200
Untrust.200
193.1.1.250/
255.255.255.0
The description will now continue with showing what a user of a virtual system, a “marketing” system, sees and the operations he or she can perform when he logs in to the system. The user logs in with his username and password:
login: vsys_marketing
password:
ns1000(marketing)->
To change the policy configuration, the user types ‘get policy’ which yields the two policies shown in Table 7 above. Now, the user can remove the first policy with the command ‘unset policy 1’ and add a new policy to the “marketing” system by typing
ns1000(marketing)-> set policy outgoing in-any out-any any permit auth
The new policy configuration can be shown by retyping the ‘get policy’ command, which yields the policies shown in Table 9 below.
TABLE 9
Modified policies for the “marketing” system
PID
Direction
Source
Destination
Service
Action
STLC
0
Incoming
Outside
MIP
HTTP
Permit
—
Any
(193.1.1.124)
2
Outgoing
Inside
Outside Any
Any
Permit-
—
Any
Auth
The user can then exit the “marketing” system and save the modified policies in the same way as the root user exited:
ns1000(marketing)-> exit
Configuration modified, save? [y]/n y
Save System Configuration . . . Done
The above examples only showed how to change a few policies and components. In the Internet security system in accordance with the invention, the following components can be independently configured in a similar way to the above example:
Firewall—The firewall device can be configured for each user to include one or more of the following mechanisms: NAT (Network Address Translation), MIP/VIP (Mapped IP, Virtual IP), User authentication, URL Blocking.
Policy—A private policy set can be configured that is applied to traffic for a particular customer. The private policy can include both incoming and outgoing policies. The policies can use entries from a global address book, a defined private address book, and a global service book.
Traffic management—Each virtual interface can be given a specific bandwidth.
Administration and management—Various functions can be configured for administration purposes, such as administrator login, mail alert, syslog, counters, logs and alarms.
Virtual LAN—The Virtual LAN can be defined on virtual interfaces within the Internet security system. Once the virtual LAN has been defined, the received VLAN traffic will be directed to the indicated virtual interface and traffic destined to the indicated virtual interface will be properly tagged with a VLAN ID.
VPN—Combined with private policies, the VPN provides secure tunneling for selected traffic going through the Internet security system. The tunneling can be PPTP, L2TP and IPSec.
Routing—Each system may define a private routing table and routing protocol.
A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims. | Methods and apparatus, including computer program products, implementing and using techniques for processing a data packet in a packet forwarding device. A data packet is received. A virtual local area network destination is determined for the received data packet, and a set of rules associated with the virtual local area network destination is identified. The rules are applied to the data packet. If a virtual local area network destination has been determined for the received data packet, the data packet is output to the destination, using the result from the application of the rules. If no destination has been determined, the data packet is dropped. A security system for partitioning security system resources into a plurality of separate security domains that are configurable to enforce one or more policies and to allocate security system resources to the one or more security domains, is also described. | 7 |
This is a Provisional of application Ser. No. 09/688,612, filed Oct. 15, 2000, now U.S. Pat. No. 6,673,242.
TECHNICAL FIELD OF THE INVENTION
The present invention provides a spiral-wound membrane module design for various membrane filtration techniques having significantly reduced fluid flow resistance in the feed stream path. Specifically, the inventive spiral-wound membrane module is designed having a corrugated entrance and exit spacers together over less than 10% of the length of the spiral wound module and a stiffener sheet wound to provide for uniform feed channel gap width.
BACKGROUND OF THE INVENTION
In the field of pressure-driven membrane separations (e.g., ultrafiltration, reverse osmosis, nanofiltration) there is frequently a problem of membrane fouling from contamination of other dissolved and suspended solids in feed streams. This kind of membrane separation has been used, for example, in apple juice clarification, waste water treatment, cheese whey desalting, potable water production, oil-water emulsion separation, etc.). This problem has been addressed in a variety of ways. For feed streams that are not fouling, hollow fiber membrane module are most efficient and cost effective means of separation. However, hollow fiber membrane designs will foul most easily and cannot be used for the majority of feed streams in industrial processing or waste treatment due to fouling problems.
The next most expensive membrane design in terms of providing the greatest membrane surface area in a vessel per cost is a spiral wound configuration. In a spiral wound configuration, a permeate spacer, a feed spacer and two membranes are wrapped around a perforated tube and glued in place. The membranes are wound between the feed spacer and the permeate spacer. Feed fluid is forced to flow longitudinally through the module through the feed spacer, and fluid passing through the membranes flows inward in a spiral through the permeate spacer to the center tube. To prevent feed fluid from entering the permeate spacer, the two membranes are glued to each other along their edges with the permeate spacer captured between them. The feed spacer remains unglued. A diagram of a cross-section of three wraps of a standard module is shown in FIG. 1 . Module assemblies are wound up to a desired diameter and the outsides are sealed. In operation, multiple modules are placed in a tubular housing and fluid is pumped through them in series. The center tubes are plumbed together to allow removal of generated permeate.
Spiral wound membrane designs have been used successfully but can also foul with higher fouling feed streams. The fouling problem in standard spiral wound membranes is often due to the nature of the feed spacer that is required to be located through each of the feed channels. In addition, the presence of the feed spacer creates significant resistance to fluid flow. A typical feed spacer is a polymeric porous net-like material that the feed must be forced through in the longitudinal direction (i.e., the length) of the spiral wound membrane. Therefore, spiral wound membrane designs can also have fouling problems in the feed spacer and membrane and incur significant fluid dynamic problems due to resistance of the feed spacer. However, spiral wound designs are less expensive than alternatives for only less-fouling feed streams.
For the most fouling feed streams (for examples, solutions containing high levels of suspended solids or tend to form gels upon concentration) a tubular design membrane module has been designed. A tubular design provides the least amount of membrane surface area per module length, and is most expensive to manufacture due to labor intensive procedures for “potting” the tubular membranes within a module. Moreover, the inlet and outlet chambers associated with tubular designs are also most expensive. Therefore, there is a need in the art to replace the tubular design with a less expensive design and still be able to process highly fouling feed streams. The present invention was made to replace the tubular design with a spiral wound design for those feed streams that could not otherwise be processed (economically) in standard membrane modules having feed spacer designs.
SUMMARY OF THE INVENTION
The present invention provides a spiral wound membrane module having a length and a radius and a circular cross section, having reduced fluid flow resistance, comprising:
(a) an envelope sandwich having a width equal to the length of the membrane module and comprising a layer of membrane next to a layer of permeate spacer material next to a stiffener means, next to a layer of permeate spacer material next to a layer of membrane, and wherein the envelope sandwich is wrapped increasing the radius of the membrane module; and
(b) a structural assembly located between each wrap of the envelope sandwich to provide an open path for each feed chamber throughout the length of the membrane module.
Preferably, the stiffener means is composed of a hard shell sheet or an extruded or calendered rib. Most preferably, a rib stiffener means run in the same direction as permeate flow and provide permeate channels. Preferably, the structural assembly extends no more than 10% of the length of the membrane module. Preferably, the structural assembly is located at both ends of the membrane module. Preferably, the membrane module further comprises a perforated or porous tube extended throughout the length of the membrane module and located axially around a cylinder axis of the membrane module. Most preferably, the perforated or porous tube is used to collect permeate.
Preferably, the stiffener in the form of a sheet is made from a rigid sheet having a thickness of from about 0.1 mm to about 3 mm, most preferably from about 0.5 mm to about 1 mm. Preferably, the stiffener in the form of a sheet is made from a rigid material selected from the group consisting of PVC (polyvinyl chloride), C-PVC (chlorinated polyvinyl chloride) polypropylene, polyethylene, acrylic, stainless steel, copper, tin, and aluminum. Most preferably, the stiffener sheet is polyethylene for food uses or PVC for non-food uses, or C-PVC for high temperature uses. Preferably, the structural assembly is a corrugated pattern ribbon. Preferably, the structural assembly is a rigid material, wherein the rigid material is selected from the group consisting of polyethylene, stainless steel, aluminum, acrylic, and polycarbonate.
The present invention further provides a process for making a spiral wound membrane module having a length and a radius and a circular cross section, having reduced fluid flow resistance, comprising
(a) assembling an envelope sandwich having a width equal to the length of the membrane module and comprising a layer of membrane next to a layer of permeate spacer material next to a layer of stiffener means next to a layer of permeate spacer material next to a layer of membrane, and wherein the envelope sandwich is wrapped increasing the radius of the membrane module;
(b) assembling a structural assembly on either end of the envelope sandwich; and
(c) wrapping the envelope sandwich having the structural assembly and glue to form the spiral wound membrane module.
Preferably, the stiffener means is composed of a hard shell sheet or an extruded or calendered rib. Most preferably, a rib stiffener means run in the same direction as permeate flow and provide permeate channels. Preferably, the process further comprises before step (c) adding glue to either end of the envelope sandwich. Preferably, the structural assembly extends no more than 10% of the length of the membrane module. Preferably, the membrane module further comprises a perforated or porous tube extending throughout the length of the membrane module and located axially around a cylinder axis of the membrane module and upon which the sandwich assembly is wrapped.
Preferably, the stiffener in the form of a sheet is made from a rigid sheet having a thickness of from about 0.1 mm to about 3 mm, most preferably from about 0.5 mm to about 1 mm. Preferably, the stiffener in the form of a sheet is made from a rigid material selected from the group consisting of PVC (polyvinyl chloride), C-PVC (chlorinated polyvinyl chloride) polypropylene, polyethylene, acrylic, stainless steel, copper, tin, and aluminum. Most preferably, the stiffener sheet is polyethylene for food uses or PVC for non-food uses, or C-PVC for high temperature uses. Preferably, the structural assembly is a corrugated pattern ribbon. Preferably, the structural assembly is a rigid material, wherein the rigid material is selected from the group consisting of polyethylene, stainless steel, aluminum, acrylic, and polycarbonate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a prior art cut away in an axial direction showing product flow direction (through the length of a module) through a feed chamber having feed spacer (cross hatched) material contained within the entire area of the feed chamber. In addition, there is permeate spacer located throughout the permeate chamber. In addition, the membrane is shown along with glue on the outer edges to maintain the integrity of the permeate chamber.
FIG. 2 shows a cut away in the axial direction of the inventive spiral-wound membrane module design showing the novel open feed channels having a stiffener sheet between membrane layers. There is also a glued plug at either end, similar to the prior art design to form the permeate chamber. In addition there is a corrugated feed chamber spreader at either end to provide for a uniform feed chamber gap maintainer.
FIG. 3 shows an outside view of the inventive spiral wound membrane module showing standard flow characteristics of feed and permeate. The end view shows the corrugated feed chamber spreader at the end.
FIG. 4 shows an end view close up again illustrating the corrugated feed chamber spreader and each layer having a membrane, permeate spacer, glue, permeate spacer and membrane.
FIG. 5 shows an embodiment of the inventive spiral wound membrane module having ribs as the stiffener means.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides an improved membrane design for spiral wound membranes that provide the cost advantages and space savings of spiral wound with superior flux and fouling characteristics. The advantage of a spiral wound membrane design prior to the present invention is that it is inexpensive and has high membrane density (˜30 m 2 per 20 cm diameter by 100 cm long element). Its drawback is that it is highly susceptible to fouling since the feed must flow longitudinally through a net-like feed spacer. The fibers of the feed spacer allow suspended solids to become lodged and blind the membrane, degrading performance and inhibiting cleaning. Pressure drops are also high in the flow through the feed spacer, which makes it impossible to achieve the fluid velocities that have been shown to provide the best performance of membranes.
Another membrane module design in common usage is the “tubular” design. In this design, the fluid is pumped at high velocity down the center of a tubular membrane (5 mm to 30 mm in diameter), and the fluid permeating the membrane is contained by an exterior housing. Often multiple tubes are bundled in a single housing. This design has the advantage that the flow path is unobstructed, allowing very high-solids fluids to be filtered. The disadvantage of this design is its high cost and low membrane density. Thus, there is a need to combine the expense and density advantages of spiral wound with flow path advantages of tubular. The present invention has achieved this.
Module Design
The invention is a spiral module design that does not require a feed spacer, thus providing the advantages of unobstructed feed channels, at far lower cost than tubular modules. Instead, the inventive membrane is a spiral wound design but without traditional spacer materials. Specifically, the present invention provides a spiral wound membrane module having a length and a radius and a circular cross section, having reduced fluid flow resistance, comprising
(a) an envelope sandwich having a width equal to the length of the membrane module and comprising a layer of membrane next to a layer of permeate spacer material next to a layer of stiffener sheet next to a layer of permeate spacer material next to a layer of membrane, and wherein the envelope sandwich is wrapped increasing the radius of the membrane module; and
(b) a structural assembly located between each wrap of the envelope sandwich to provide an open path for each feed chamber throughout the length of the membrane module.
Essentially, the inventive membrane provides a “layered” approach to a spiral wound design with a stiff backing material and no spacer material through most of the flow path. The layered membrane sandwich is shown in a cut-away view of three channels in FIG. 2 wherein the sandwich layer for the middle section of the spiral wound module forms a membrane (green) on a permeate spacer material (red), on a polymeric stiffener material (dark blue), permeate spacer material (red), and another membrane (green). Thus, the membrane is always between the permeate channel kept open by conventional spacer technology and a larger feed channel kept open by the polymeric stiffener (though the larger middle section of the module) and without conventional spacer technology. Thus, the vast majority of the feed channel is open to significantly improve the flow rates and pressure drips, especially for high suspended solids feed streams (e.g., landfill leachate).
Further with reference to FIG. 2 , either end of the module has a feed channel spacer to align the polymeric stiffener sandwich to have open feed channels, preferably a corrugated plastic material as shown in FIG. 2 and as a “corrugated spacer” in FIG. 4 , and glue ( FIG. 2 , light blue) to anchor the polymeric stiffener sandwich component and provide for permeate to be channeled to the center of the spiral wound module.
Therefore, the inventive spiral wound module is designed in a similar fashion to a typical spiral wound membrane module except that there is no feed chamber spacer at all through most of the middle segment of the module (i.e., 90%+ of the length) and the feed chamber remains patent with superior flow characteristics and pressure drops. This inventive design is illustrated in FIGS. 2-5 . The design is similar to a standard spiral wound design, except it requires no feed spacer. In a standard spiral wound module the feed spacer material fills the entire feed channel. In the inventive design, by contrast, a thick, corrugated spacer is used only at the front and back edge of the feed channel. Fluid pressure then keeps the membranes in contact with the permeate spacer and keeps the feed channels unobstructed. A uniform feed channel width is ensured by employing a plastic stiffener in the permeate channel. The stiffener is typically 0.5 mm to 1 mm thick and made from PVC, polypropylene, or polyethylene. To provide for permeate flow on both sides of the stiffener, two permeate spacers are used with the stiffener between them. As in the standard spiral wound design, the membranes are glued along the edges, capturing the permeate spacers and stiffener.
Ultrafiltration modules with the inventive design have been made and tested for performance criteria. Specifically, 24 cm diameter by 60 cm long element with a feed channel gap width of 3 mm had a pressure drop of 1 kPa when feed fluid velocities inside the module were 0.5 m/sec. The module contained an effective membrane area of 10 m 2 . To put these data into perspective, the pressure drop experienced is about ten-fold lower than a conventional spiral wound device of about the same area and size having a conventional feed chamber spacer.
The inventive membrane module design can be applied to a variety of applications ranging from microfiltration through ultrafiltration to reverse osmosis. Initial tests of the fouling resistance of the membrane have been conducted by ultrafiltration of a heavily soiled, machine shop cutting fluid containing emulsified oil. At 75% water removal, 0.5 m/sec cross-flow velocity, and 300 kpa pressure, the membrane flux declined less than 20% in 100 hours of operation without any cleanings. A similar membrane in a traditional spiral wound membrane module would foul and a much higher rate. | There is disclosed a spiral-wound membrane module design for various membrane filtration techniques having significantly reduced fluid flow resistance in the feed stream path. Specifically, the inventive spiral-wound membrane module is designed having a corrugated entrance and exit spacers together over less than 10% of the length of the spiral wound module and a stiffener sheet wound to provide for uniform feed channel gap width. | 8 |
TECHNICAL FIELD
[0001] The technical field which deals with the present invention is about prefabricated buildings, specifically the ones referred to modular type constructions.
STATE OF THE ART
[0002] The following techniques described in this document differ from the conventional prefabricated construction techniques, where the conventional prefabricated constructions do not manufacture walls, instead, they are manufactured (in situ) from (prefabricated) simple panels, which require first completing the exterior structure, then the power current installation and the placement of doors and windows, resulting into additional operations and costs, considering that these constructions also are subject to individual client's designs, translating into individual initiation and operation costs, while this alternative system, is based on predetermined modular house, which represents the core invention, since these models are created on the basis of three (3) related inventions, which results in simplifying dozens of processes or maybe more, of a typical construction. In the manufacture of these three (3) interrelated basic inventions with which, the predetermined models hereunder presented, were finally developed. These three (3) basic inventions possess unique claim characteristics, which achieve an unequaled simplicity in the construction of prefabricated houses, result in savings in operation costs resulting in a very low cost and price. This document describes a “UNIT OF INVENTION”.
“UNIT OF INVENTION” DESCRIPTION
[0003] The following invention consists in the integral manufacture of various predetermined house models in bases of WALLS, CONNECTORS and ROOF COMPONENTS completely equal one to the other, in order to optimize the process.
[0004] This means, that with three (3) types of sub-products, we can build a house. This does not imply that in some punctual cases, some unnecessary details may be omitted, which simplify even more the manufacturing process of these three (3) basic elements; inventions in their own right.
[0005] This system achieves two important things: First the setup of a very simple factory, since only three (3) elements need to be manufactured, making the initial capital investment much smaller than what it would normally be, and second optimizing a house construction process and cost operation into a house manufacturing process and cost operation. (very important), meaning that with this integral system, the construction processes are replaced with manufacturing processes, optimizing in this way the production capacity, as well as optimizing the production system, and optimizing the products due to the possibility of specialization in the production process. It's worth mentioning that if on one side we have the benefits of serial production just described, on the other we are limited to our plans and to the predetermined requirements of our system of production and manufacture. We want to emphasize that this system finally results in making houses, but for this end, we need to do three (3) semi-products with specific details which are explained hereunder, which are universal and unique in a construction, and each one does not function without the other components, reason why it is called an integral system. It is very important to highlight in our application that our system is a group of inventions related to each other, denominated “UNIT OF INVENTION”.
[0006] *Adding another virtue to the invention, we are achieving a new standard of quality of life for the low income families thanks to the reduction in operating costs achieved with the Units of Invention.
[0007] The three System Elements are three related inventions which are components that make up a principal invention, which are the models shown hereunder.
a) The Universal Wall:
[0009] The walls have the distinction to possess all exterior and interior finishing detail, as well as door, window, drain and water circuits, outlet and inlet switches. These walls contain a unique power current circuit in the interior which allows a coincidence with the other walls, as well as when referred to the plumbing circuit.
[0010] This wall is a standard piece, which is made so that this same unit can be used for the assembly of various models of modular homes, that is universal standard walls, which can be connected wall with wall, through a universal connector, and always after connecting, it permits the correct functioning of the services (electrical and plumbing) once the installation of the houses is complete. With respect to this last point, this standard universal prefabricated wall contains in a fixed and predetermined position, spaces, openings, electrical and plumbing circuit, as well as switches, sockets, amongst other electrical devices, as well as predetermined positions for doors and windows.
[0011] The wall may function with various construction materials, such as the concrete, wood, melamine, plastic, metal amongst others. The universal walls rest in channels placed in the floor which seal and waterproof all of the house perimeter and interior areas, so that once connected these walls form the desired modules according to the predetermined model plans.
[0012] All universal walls have in common that the exhibit a 2.40 m high, 3 meters high and 10 cm thickness; and all exhibit the same power, water and drain circuit, ready to be used, or simply circumvent it if not required. The simplification of the dimension and circuits positions is a factor for the lowering the manufacturing operations, for being only one the wall to manufacture and in this way optimize the production speed to the maximum, since it is a universal wall which will be manufactured in series.
b) Universal Wall Connector:
[0014] It is constituted by a square tube where each one of the sides have two guides which serve to fasten the “C” channel which finally will hold the wall, and a cover which covers the unused sides. In the top inner part of the connector, are the power current connector “female-ended” which split on all sides and will plug in with the wall connectors “male-ended”.
[0015] In the inferior part of the Universal Connector, is a free pass which gives play to the flexible tubes (not rigid) that come out of the wall, for the water connection which is always straight in our designs.
[0016] The inner part of the Universal Connector is filled with thermal acoustic material, to insulate the cold/water pass and sound through them.
[0017] Finally the cover guides for the sides in disuse, which also function as decorative pieces.
[0018] This Universal Connector was created to standardized spaces composed by the Universal Walls by a facilitating their homogeneous placement, and the pass of power, water and other services through them.
[0019] In the sides of the Universal Walls are the Universal Connectors, which, as their name indicates serve to connect one Universal Wall with another, at the same time serve to connect the circuits (cables and ducts), in such a way that, when the placement is finished, all circuits of water and drain and light and power switch will be ready to use.
[0020] Within our Universal Connector, we have an electric power pass, permitting the necessary current flow to each wall at the moment of installation.
[0021] We also have, covers for the sides of the Universal Connector that are not in use, or which are not necessary for the moment until the next house remodeling.
[0022] Once connected the light and water and their respective plugs and jacks, we use bolts to bolt in the “C” channel of the Universal Connector with the Universal Wall, in order to secure it in this way.
c) Universal Roof Piece
[0024] The roof is a piece with strategic electric current connection points, which coincide symmetrically one with the other with the wall outlet point, which is special for its position and coincidence in all our house models constructed with this system, and which are numbered and shown in our claims and figures. This roof piece, once installed, will have the lights placed and correctly functioning in all of the house, by being in coordination with the spatial distribution of the light switches in all of the Universal Walls, resulting in the correct “off and on” switching of roof lights.
[0025] These roof pieces are fastened one to the other with metal plates which serve as leveling pins, to obtain an even and leveled roof , a flat ceiling is seen from the inside of the house, and the view from the outside shows a gable roof, or flat roof without changing the system, it being an obvious detail. In the graphics we appreciate a roof piece where in each extreme, it has a square shape, one smaller than the other, which permits mounting these two extremes, while joining roof blocks from right to left, instead than from bottom end to upper end, in order to achieve a waterproof effect between blocks or roof pieces. Our roof piece is also symmetrical and universal, as the Universal Wall.
[0026] This Universal Roof pieces has a hollow interior where the light system of cold light has already been installed, chosen not only for energy savings but also because it offers higher security than conventional systems of light. Each Universal Roof piece has a current inlet and an outlet always in the same site, it has Universal Roof piece to Universal Roof piece auto connectors, as well as Universal Roof piece to Universal Wall direct connections, plugable to one another, always in the same site and position, making thus our roof pieces a Universal Roof pieces, characteristic which is crucial in our system, due to its simplicity and operation savings.
BRIEF FIGURE DESCRIPTION
[0027] We want to make clear that in order to capture explanatory figures in this document, circumscribe the system hereto described, to the materials exposed in certain figures. In this system or unit of invention, no matter what materials are used, what matters is the correct functioning of the system.
[0028] FIG. 1 : This figures shows the basic wall, without details, of 2.40 mts high and 3.00 mts wide and 10 cm thick.
[0029] FIG. 2 : This figures shows the position of the door, window, power switch, power outlet in each wall, the door and window can be bypassed in case of not being needed, creating savings in specific cases.
[0030] FIG. 3 : Power current position links are shown in green ( 3 . 1 ) and water and sewer connection link in blue ( 3 . 2 ).
[0031] FIG. 4 : Another view of the power current and water and sewer links ( 3 . 1 , 3 . 2 ).
[0032] FIG. 5 : Lateral view of the wall with water and current links.
[0033] FIG. 6 : View in perspective of wall/roof power current links ( 6 . 1 ) and electrical outlet and switch ( 2 . 2 ).
[0034] FIG. 7 : Possible internal structure of universal wall, not necessarily the only one.
[0035] FIG. 8 : Shows wall fastening channels.
[0036] FIG. 9 : A possible inner structural distribution of the universal wall, frontal view.
[0037] FIG. 10 : Electrical distribution of the universal wall.
[0038] FIG. 11 : Wall with water outlets and plumbing network links.
[0039] FIG. 12 : View in perspective of wall connector with interconnecting channels.
[0040] FIG. 13 : 3-D view of the “C” channel showing “T” rails, which fit the square tube guides (connector), shown hereunder.
[0041] FIG. 14 : Plant view with the rails placed and in placement as well.
[0042] FIG. 15 : Perspective view of the decorative cover of the connector.
[0043] FIG. 16 : Explains the positions of the placement of channels, which can be of 2 to 4 used sides.
[0044] FIG. 17 : Sample of a current network distribution for it to be universal.
[0045] FIG. 18 : Plant view of a sample of electric distribution.
[0046] FIG. 19 : Sample of connections of wall and floor.
[0047] FIG. 20 : Sample of roof piece and its structural parts, such as special top structures for right to left coupling, flat support, and a top linking structure.
[0048] FIG. 21 : Sample of electrical current inlet position in the roof piece , unique light position in all pieces and current network.
[0049] FIG. 22 : Another lateral view of the roof piece.
[0050] FIG. 23 : Depicts special form of coverage, where the left side wraps around the rights side, in such a way as to prevent water leaking; view of three separate roof pieces, ready for right to left coupling.
[0051] FIG. 24 : Top Plant view of the distribution of all the pieces that make up the roof and the fit of the wall and roof connectors.
DETAILED DESCRIPTION OF THE INVENTION
[0052] An integral system of assembly and fabrication of architectural modular houses, which simplifies all building construction processes to three basic elements, meaning simplifying the construction of building to a process of building installation, with intelligent and interchangeable walls, which include a) wall with a network for an electrical circuit, plumbing circuit; b) wall to wall connectors which give symmetry and homogeneity to the distributions, a requisite which became indispensable in order to achieve the universality and homogeneity of the basic elements; c) universal roof which make the installation simple and quick.
a) The Universal Wall
[0053] The walls have the distinction to possess all exterior and interior finishing detail, as well as door, window, drain and water circuits, outlet and inlet switches. These walls contain a unique power current circuit in the interior which allows an coincidence with the other walls, as well as when referred to the plumbing circuit.
[0054] This wall is a standard piece, which is made so that this same unit can be used for the assembly of various models of modular homes, that is universal standard walls, which can be connected wall with wall, through a universal connector, and always after connecting, it permits the correct functioning of the services (electrical and plumbing) once the installation of the houses is complete. With respect to this last point, this standard universal prefabricated wall contains in a fixed and predetermined position, spaces, openings, electrical and plumbing circuit, as well as switches, sockets, amongst other electrical devices, as well as predetermined positions for doors and windows.
[0055] The wall may function with various construction materials, such as the concrete, wood, melamine, plastic, metal amongst others. The universal walls rest in channels placed in the floor which seal and waterproof all of the house perimeter and interior areas, so that once connected these walls form the desired modules according to the predetermined model plans.
[0056] All universal walls have in common that the exhibit a 2.40 m high, 3 meters high and 10 cm thickness; and all exhibit the same power, water and drain circuit, ready to be used, or simply circumvent it if not required. The simplification of the dimension and circuits positions is a factor for the lowering the manufacturing operations, for being only one the wall to manufacture and in this way optimize the production speed to the maximum, since it is a universal wall which will be manufactured in series.
b) The Universal Connector
[0057] Conformed by a universal connector ( 12 ) which is a structural quadrilateral tube, characterized because in the interior it contains a network of electrical wiring in the top part, and a free bass for plumbing piping in the inferior part, where the connection points in the wall ( 1 ) and of coupling and fastening structure of the “C” channel, which holds the wall ( 1 ).
[0058] Additionally, the connector ( 12 ) may rest on channels which are found in the perimeter of the house and interiors for a better alignment, disposition and built of living spaces.
[0059] The connector's empty spaces ( 13 ) may be filled with thermo-acoustic material, to minimize sound and temperature fluctuations.
[0060] The “C” channel ( 13 ), is characterized because it supports a wall ( 1 ) and facilitates its connection with the connector ( 12 ), that is with another wall ( 1 ), it has 2 spaces, where the space is found in the top part and permits the pass of the electrical wiring, and the bottom spacing permits the pass of the plumbing circuit; it is characterized as well because it has the channels which are coupled to the guides.
[0061] The top cover ( 15 ) has an exterior and interior part, where the exterior part is flat and the interior part has channels which couple to the guides.
c) The Roof Piece
[0062] The roof ( 20 ) is composed, by pieces which are characterized because they have a universal interior structure which contains the electrical wiring network, and has a linear form, also the top plate of the roof piece has a water fall aligned to the house roof, the structure, is covered by the top and bottom part respectively, for a better finishing and to cover more effectively the structure. The structure of the bottom plate has two holes for the placing of lightning fixtures, while the structure of the top plate does not have holes. Each piece also possesses a top structure in its superior part, which serves as a hook to other roof pieces ( 20 ), like mouth-and-tongue, and is characterized because its possesses a similar dimension to the plate underneath, with an transversal area which includes a central trough and elevated unequal quadrangular borders, one lesser than the other, which serves for the hitching of one top structure from another roof piece ( 20 ).
Prototype
[0063] In order to realize the actual invention, a prototype was constructed that served to define the function details which brought conclusions which led to this invention unit. | This system has achieved in making unique pieces in order to generalize the construction of buildings by simplifying the construction process to the manufacture of three (3) products, to achieve our modular house models.
This simplification in the manufacture process results in the simplification of the infrastructure of the installed plant capacity. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent Application Ser. No. 60/334,502, filed Nov. 30, 2001.
BACKGROUND OF THE INVENTION
This invention relates to aryl fused azapolycyclic compounds, as defined more specifically by formula I below. Compounds of formula I bind to neuronal nicotinic acetylcholine specific receptor sites and are useful in modulating cholinergic function. Such compounds are useful in the treatment of inflammatory bowel disease (including but not limited to ulcerative colitis, pyoderma gangrenosum and Crohn's disease), irritable bowel syndrome, spastic dystonia, chronic pain, acute pain, celiac sprue, pouchitis, vasoconstriction, anxiety, panic disorder, depression, bipolar disorder, autism, sleep disorders, jet lag, amyotrophic lateral sclerosis (ALS), cognitive dysfunction, hypertension, bulimia, anorexia, obesity, cardiac arrythmias, gastric acid hypersecretion, ulcers, pheochromocytoma, progressive supranuclear palsy, chemical dependencies and addictions (eq., dependencies on, or addictions to nicotine (and/or tobacco products), alcohol, benzodiazepines, barbiturates, opioids or cocaine), headache, migraine, stroke, traumatic brain injury (TBI), obsessive-compulsive disorder (OCD), psychosis, Huntington's chorea, tardive dyskinesia, hyperkinesia, dyslexia, schizophrenia, multi-infarct dementia, age-related cognitive decline, epilepsy, including petit mal absence epilepsy, senile dementia of the Alzheimer's type (AD), Parkinson's disease (PD), attention deficit hyperactivity disorder (ADHD) and Tourette's Syndrome.
The compounds of this invention may also be used in combination with an antidepressant such as, for example, a tricyclic antidepressant or a serotonin reuptake inhibiting antidepressant (SRI), in order to treat both the cognitive decline and depression associated with AD, PD, stroke, Huntington's chorea or traumatic brain injury (TBI); in combination with muscarinic agonists in order to stimulate both central muscarinic and nicotinic receptors for the treatment, for example, of ALS, cognitive dysfunction, age-related cognitive decline, AD, PD, stroke, Huntington's chorea and TBI; in combination with neurotrophic factors such as NGF in order to maximize cholinergic enhancement for the treatment, for example, of ALS, cognitive dysfunction, age-related cognitive decline, AD, PD stroke, Huntington's chorea and TBI; or in combination with agents that slow or arrest AD such as cognition enhancers, amyloid aggregation inhibitors, secretase inhibitors, tau kinase inhibitors, neuronal anti-inflammatory agents and estrogen-like therapy.
Other compounds that bind to neuronal nicotinic receptor sites are referred to in U.S. patent application Ser. No. 08/963,852, which was filed on Nov. 4, 1997. The foregoing application is owned in common with the present application, and is incorporated herein by reference in its entirety. In particular, a number of compounds which bind to neuronal nicotinic receptor sites and are useful in modulating cholinergic function are referred to in International Patent Publication No. WO 01/62736, filed Feb. 8, 2001; International Patent Publication No. WO 99/35131, filed Nov. 13, 1998; International Patent Publication No. WO 99/55680, filed Apr. 8, 1999; International Patent Publication No. WO 98/18798, filed Oct. 15, 1997; U.S. Pat. No. 5,977,131, filed Mar. 31, 1998; U.S. Pat. No. 6,020,335, filed Nov. 4, 1997; and European Patent Publication No. EP 0 955 301 A2, filed Mar. 25, 1999. The foregoing applications, owned in common with the present application and incorporated herein by reference in their entirety.
SUMMARY OF THE INVENTION
This invention relates to aryl fused azapolycyclic compounds of the formula (I)
R 1 is independently hydrogen or —COOR 4 , wherein R 4 is a group of formula
R 2 and R 3 , together with the benzo ring to which they are attached, form a bicyclic ring system selected from the following:
wherein one of the carbon atoms of ring A can optionally be replaced with oxygen or N(C 1 -C 6 )alkyl; wherein R 11 and R 12 are selected, independently, from hydrogen, (C 1 -C 6 )alkyl; and (C 1 -C 6 )alkoxy-(C 0 -C 6 )alkyl- wherein the total number of carbon atoms does not exceed six and wherein any of the alkyl moieties may optionally be substituted with from one to seven fluorine atoms; nitro, cyano, halo, amino, (C 1 -C 6 )alkylamino-, ((C 1 -C 6 )alkyl) 2 amino-, —CO 2 R 5 , —CONR 6 R 7 , —SO 2 NR 8 R 9 , —C(═O)R 10 , —XC(═O)R 10 , phenyl, monocyclic heteroaryl, or when attached to a nitrogen atom, a group of formula:
each R 5 , R 6 , R 7 , R 8 , R 9 and R 10 is selected, independently, from hydrogen and (C 1 -C 6 )alkyl, or R 6 and R 7 , or R 8 and R 9 together with the nitrogen to which they are attached, form a pyrrolidine, piperidine, morpholine, azetidine, piperazine, —N—(C 1 -C 6 )alkylpiperazine or thiomorpholine ring, or a thiomorpholine ring wherein the ring sulfur is replaced with a sulfoxide or sulfone; and each X is, independently, (C 1 -C 6 )alkylene; with the proviso that when R 1 is H, then at least one of R 11 or R 12 must be a group of formula:
attached to a nitrogen atom in the ring formed by groups R 2 and R 3 , and forming an ammonium ion center on that nitrogen atom if necessary to accommodate the existing bonding relationships; and pharmaceutically acceptable salts of such compounds.
Examples of possible heteroaryl groups within the definition of R 2 and R 3 are the following: thienyl, oxazoyl, isoxazolyl, pyridyl, pyrimidyl, thiazolyl, tetrazolyl, isothiazolyl, triazolyl, imidazolyl, tetrazolyl, pyrrolyl and the following groups:
wherein one of R 13 and R 14 is hydrogen or (C 1 -C 6 )alkyl, and the other is a bond to the benzo ring of formula I.
Preferred embodiments of formula I are wherein R 2 and R 3 , together with the benzo ring to which they are attached, form a bicyclic ring system selected from the following:
wherein R 11 and R 12 are as defined above.
More preferred embodiments of formula I are wherein R 2 and R 3 , together with the benzo ring to which they are attached, form a group:
wherein R 11 and R 12 are as defined above.
The most preferred embodiments of formula I of the invention are selected from the group consisting of:
Other preferred compounds of the invention comprise:
wherein R 15 is an oxo group, which forms a carbonyl functional with any of the available carbon atoms on the unsaturated portion of the molecule.
Unless otherwise indicated, the term “halo”, as used herein, includes fluoro, chloro, bromo and iodo.
Unless otherwise indicated, the term “alkyl”, as used herein, includes straight chain moieties, and where the number of carbon atoms suffices, branched and cyclic moieties.
The term “alkoxy”, as used herein, means “—O-alkyl” or “alkyl-O—”, wherein “alkyl” is defined as above.
The term “alkylene, as used herein, means an alkyl radical having two available bonding sites (i.e., -alkyl-), wherein “alkyl” is defined as above.
Unless otherwise indicated, the term “one or more substituents”, as used herein, refers to from one to the maximum number of substituents possible based on the number of available bonding sites.
The term “treatment”, as used herein, refers to reversing, alleviating, inhibiting the progress of, or preventing the disorder or condition to which such term applies, or one or more symptoms of such condition or disorder. The term “treatment”, as used herein, refers to the act of treating, as “treating” is defined immediately above.
The compounds of formula I may have optical centers and therefore may occur in different enantiomeric configurations. The invention includes all enantiomers, diastereomers, and other stereoisomers of such compounds of formula I, as well as racemic and other mixtures thereof.
The present invention also relates to all radiolabeled forms of the compounds of the formula I. Preferred radiolabeled compounds of formula I are those wherein the radiolabels are selected from as 3 H, 11 C, 14 C, 18 F, 123 I and 125 I. Such radiolabeled compounds are useful as research and diagnostic tools in metabolism studies, such as pharmacokinetics studies, etc., and in binding assays in both animals and man.
The present invention also relates to a pharmaceutical composition for use in reducing nicotine addiction or aiding in the cessation or lessening of tobacco use in a mammal, including a human, comprising an amount of a compound of the formula I, or a pharmaceutically acceptable salt thereof, that is effective in reducing nicotine addiction or aiding in the cessation or lessening of tobacco use and a pharmaceutically acceptable carrier.
The present invention also relates to a method for reducing nicotine addiction or aiding in the cessation or lessening of tobacco use in a mammal, including a human, comprising administering to said mammal an amount of a compound of the formula I, or a pharmaceutically acceptable salt thereof, that is effective in reducing nicotine addiction or aiding in the cessation or lessening of tobacco use.
The present invention also relates to a method of treating a disorder or condition selected from inflammatory bowel disease (including but not limited to ulcerative colitis, pyoderma gangrenosum and Crohn's disease), irritable bowel syndrome, spastic dystonia, chronic pain, acute pain, celiac sprue, pouchitis, vasoconstriction, anxiety, panic disorder, depression, bipolar disorder, autism, sleep disorders, jet lag, amyotrophic lateral sclerosis (ALS), cognitive dysfunction, hypertension, bulimia, anorexia, obesity, cardiac arrythmias, gastric acid hypersecretion, ulcers, pheochromocytoma, progressive supranuclear palsy, chemical dependencies and addictions (e.q., dependencies on, or addictions to nicotine (and/or tobacco products), alcohol, benzodiazepines, barbiturates, opioids or cocaine), headache, migraine, stroke, traumatic brain injury (TBI), obsessive-compulsive disorder (OCD), psychosis, Huntington's chorea, tardive dyskinesia, hyperkinesia, dyslexia, schizophrenia, multi-infarct dementia, age-related cognitive decline, epilepsy, including petit mal absence epilepsy, senile dementia of the Alzheimer's type (AD), Parkinson's disease (PD), attention deficit hyperactivity disorder (ADHD) and Tourette's Syndrome in a mammal, comprising administering to a mammal in need of such treatment an amount of a compound of the formula I, or a pharmaceutically acceptable salt thereof, that is effective in treating such disorder or condition.
The present invention also relates to a pharmaceutical composition for treating a disorder or condition selected from inflammatory bowel disease (including but not limited to ulcerative colitis, pyoderma gangrenosum and Crohn's disease), irritable bowel syndrome, spastic dystonia, chronic pain, acute pain, celiac sprue, pouchitis, vasoconstriction, anxiety, panic disorder, depression, bipolar disorder, autism, sleep disorders, jet lag, amyotrophic lateral sclerosis (ALS), cognitive dysfunction, hypertension, bulimia, anorexia, obesity, cardiac arrythmias, gastric acid hypersecretion, ulcers, pheochromocytoma, progressive supranuclear palsy, chemical dependencies and addictions (e.q., dependencies on, or addictions to nicotine (and/or tobacco products), alcohol, benzodiazepines, barbiturates, opioids or cocaine), headache, migraine, stroke, traumatic brain injury (TBI), obsessive-compulsive disorder (OCD), psychosis, Huntington's chorea, tardive dyskinesia, hyperkinesia, dyslexia, schizophrenia, multi-infarct dementia, age-related cognitive decline, epilepsy, including petit mal absence epilepsy, senile dementia of the Alzheimer's type (AD), Parkinson's disease (PD), attention deficit hyperactivity disorder (ADHD) and Tourette's Syndrome in a mammal, comprising an amount of a compound of the formula I, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.
This invention also relates to the pharmaceutically acceptable acid addition salts of the compounds of formula I. Examples of pharmaceutically acceptable acid addition salts of the compounds of formula I are the salts of hydrochloric acid, p-toluenesulfonic acid, fumaric acid, citric acid, succinic acid, salicylic acid, oxalic acid, hydrobromic acid, phosphoric acid, methanesulfonic acid, tartaric acid, malic acid, di-p-toluoyl tartaric acid, and mandelic acid, as well salts formed from other acids known to those of skill in the art to form pharmaceutically acceptable acid addition salts to basic compounds. Other possible acid addition salts are, e.g., salts containing pharmaceutically acceptable anions, such as the hydroiodide, nitrate, sulfate or bisulfate, phosphate or acid phosphate, acetate, lactate, gluconate, saccharate, benzoate, methanesulfonate, ethanesulfonate, benzenesulfonate, and pamoate (i.e., 1.1′-methylene-bis-(2-hydroxy-3-naphthoate)salts).
DETAILED DESCRIPTION OF THE INVENTION
Except where otherwise stated, R 1 through R 15 and structural formula I in the reaction schemes and discussion that follow are defined as above. Methods of synthesizing aryl-fused azapolycyclic compound precursors are set forth in International Patent Publication No. WO 01/62736, filed Feb. 8, 2001; and International Patent Publication No. WO 99/35131, filed Nov. 13, 1998; incorporated herein by reference in their entirety.
A number of studies have been conducted on precursor compounds to those of formula I of the present invention. In particular, studies have been carried out on 5,8,14-triazatetracyclo[10.3.1.0 2,11 0.0 4,9 ]-hexadeca-2(11),3,5,7,9-pentaene:
Means of the synthesis of this compound may be found International Patent Publication No. WO 99/35131 and WO 01/62736. In analyses of this particular precursor compound in liver microsomes, it was demonstrated that 5,8,14-triazatetracyclo[10.3.1.0 2,11 0.0 4,9 ]-hexadeca-2(11),3,5,7,9-pentaene underwent N-carbamoyl glucuronidation to form an active compound of formula:
when specific conditions and cofactors were used to support this type of biotransformation reaction (bicarbonate buffer, CO 2 atmosphere, UDPGA).
The compound 5,8,14-triazatetracyclo[10.3.1.0 2,11 0.0 4,9 ]-hexadeca-2(11),3,5,7,9-pentaene has also been studied in vivo (rat, monkey, mouse, and human). Metabolite structures are described in Scheme I below. Metabolites in human circulation included the N-carbamoyl glucuronide, N-formyl:
and N-hexose conjugates (at either or both the quinoxaline nitrogen position and the azabicyclic nitrogen position)
as well as a minor metabolite (assigned as a carbonyl metabolite as the molecular weight was 14 mass units greater than 5,8,14-triazatetracyclo[10.3.1.0 2,11 0.0 4,9 ]-hexadeca-2(11),3,5,7,9-pentaene):
wherein R 15 is an oxo group, which forms a carbonyl functional with any of the available carbon atoms on the unsaturated portion of the molecule.
The N-carbamoyl glucuronide represents an unusual, albeit not unprecedented metabolite that arises via association of carbon dioxide with the secondary amine followed by glucuronidation. Preclinical species possessed these metabolites in addition to some minor putative oxidative metabolites. The only excreted metabolites in human were the hydroxyquinoxaline metabolite (2.9% of dose):
and N-carbamoyl glucuronide (3.6% of dose). The N-carbamoyl glucuronide was present in rat and monkey. The hydroxyquinoxaline metabolite was also shown to be present in rat urine.
The compounds of the formula I and their pharmaceutically acceptable salts (hereafter “the active compounds”) can be administered via either the oral, transdermal (e.g., through the use of a patch), intranasal, sublingual, rectal, parenteral or topical routes. Transdermal and oral administration are preferred. These compounds are, most desirably, administered in dosages ranging from about 0.01 mg up to about 1500 mg per day, preferably from about 0.1 to about 300 mg per day in single or divided doses, although variations will necessarily occur depending upon the weight and condition of the subject being treated and the particular route of administration chosen. However, a dosage level that is in the range of about 0.001 mg to about 10 mg per kg of body weight per day is most desirably employed. Variations may nevertheless occur depending upon the weight and condition of the persons being treated and their individual responses to said medicament, as well as on the type of pharmaceutical formulation chosen and the time period and interval during which such administration is carried out. In some instances, dosage levels below the lower limit of the aforesaid range may be more than adequate, while in other cases still larger doses may be employed without causing any harmful side effects, provided that such larger doses are first divided into several small doses for administration throughout the day.
The active compounds can be administered alone or in combination with pharmaceutically acceptable carriers or diluents by any of the several routes previously indicated. More particularly, the active compounds can be administered in a wide variety of different dosage forms, e.g., they may be combined with various pharmaceutically acceptable inert carriers in the form of tablets, capsules, transdermal patches, lozenges, troches, hard candies, powders, sprays, creams, salves, suppositories, jellies, gels, pastes, lotions, ointments, aqueous suspensions, injectable solutions, elixirs, syrups, and the like. Such carriers include solid diluents or fillers, sterile aqueous media and various non-toxic organic solvents. In addition, oral pharmaceutical compositions can be suitably sweetened and/or flavored. In general, the active compounds are present in such dosage forms at concentration levels ranging from about 5.0% to about 70% by weight.
For oral administration, tablets containing various excipients such as microcrystalline cellulose, sodium citrate, calcium carbonate, dicalcium phosphate and glycine may be employed along with various disintegrants such as starch (preferably corn, potato or tapioca starch), alginic acid and certain complex silicates, together with granulation binders like polyvinylpyrrolidone, sucrose, gelatin and acacia. Additionally, lubricating agents such as magnesium stearate, sodium lauryl sulfate and talc can be used for tabletting purposes. Solid compositions of a similar type may also be employed as fillers in gelatin capsules; preferred materials in this connection also include lactose or milk sugar, as well as high molecular weight polyethylene glycols. When aqueous suspensions and/or elixirs are desired for oral administration the active ingredient may be combined with various sweetening or flavoring agents, coloring matter and, if so desired, emulsifying and/or suspending agents, together with such diluents as water, ethanol, propylene glycol, glycerin and various combinations thereof.
For parenteral administration, a solution of an active compound in either sesame or peanut oil or in aqueous propylene glycol can be employed. The aqueous solutions should be suitably buffered (preferably pH greater than 8), if necessary, and the liquid diluent first rendered isotonic. These aqueous solutions are suitable for intravenous injection purposes. The oily solutions are suitable for intraarticular, intramuscular and subcutaneous injection purposes. The preparation of all these solutions under sterile conditions is readily accomplished by standard pharmaceutical techniques well known to those skilled in the art.
It is also possible to administer the active compounds topically and this can be done by way of creams, a patch, jellies, gels, pastes, ointments and the like, in accordance with standard pharmaceutical practice.
Biological Assay
The effectiveness of the active compounds in suppressing nicotine binding to specific receptor sites is determined by the following procedure which is a modification of the methods of Lippiello, P. M. and Fernandes, K. G. (in The Binding of L -[ 3 H]Nicotine To A Single Class of High - Affinity Sites in Rat Brain Membranes, Molecular Pharm ., 29, 448-54, (1986)) and Anderson, D. J. and Arneric, S. P. (in Nicotinic Receptor Binding of 3 H - Cytisine, 3 H - Nicotine and 3 H - Methylcarmbamylcholine In Rat Brain, European J. Pharm ., 253, 261-67 (1994)).
Procedure
Male Sprague-Dawley rats (200-300 g) from Charles River were housed in groups in hanging stainless steel wire cages and were maintained on a 12 hour light/dark cycle (7 a.m.-7 p.m. light period). They received standard Purina Rat Chow and water ad libitum.
The rats were killed by decapitation. Brains were removed immediately following decapitation. Membranes were prepared from brain tissue according to the methods of Lippiello and Fernandez ( Molec Pharmacol , 29, 448-454, (1986) with some modifications. Whole brains were removed, rinsed with ice-cold buffer, and homogenized at 0° in 10 volumes of buffer (w/v) using a Brinkmann Polytron™, setting 6, for 30 seconds. The buffer consisted of 50 mM Tris HCl at a pH of 7.5 at room temperature. The homogenate was sedimented by centrifugation (10 minutes; 50,000×g; 0 to 4° C. The supernatant was poured off and the membranes were gently resuspended with the Polytron and centrifuged again (10 minutes; 50,000×g; 0 to 4° C. After the second centrifugation, the membranes were resuspended in assay buffer at a concentration of 1.0 g/100 mL. The composition of the standard assay buffer was 50 mM Tris HCl, 120 mM NaCl, 5 mM KCl, 2 mM MgCl 2 , 2 mM CaCl 2 and has a pH of 7.4 at room temperature.
Routine assays were performed in borosilicate glass test tubes. The assay mixture typically consisted of 0.9 mg of membrane protein in a final incubation volume of 1.0 mL. Three sets of tubes were prepared wherein the tubes in each set contained 50 μL of vehicle, blank, or test compound solution, respectively. To each tube was added 200 μL of [ 3 H]-nicotine in assay buffer followed by 750 μL of the membrane suspension. The final concentration of nicotine in each tube was 0.9 nM. The final concentration of cytisine in the blank was 1 μM. The vehicle consisted of deionized water containing 30 μL of 1 N acetic acid per 50 mL of water. The test compounds and cytisine were dissolved in vehicle. Assays were initiated by vortexing after addition of the membrane suspension to the tube. The samples were incubated at 0 to 4° C. in an iced shaking water bath. Incubations were terminated by rapid filtration under vacuum through Whatman GF/B™ glass fiber filters using a Brandel™ multi-manifold tissue harvester. Following the initial filtration of the assay mixture, filters were washed two times with ice-cold assay buffer (5 m each). The filters were then placed in counting vials and mixed vigorously with 20 ml of Ready Safe™ (Beckman) before quantification of radioactivity. Samples were counted in a LKB Wallach Rackbeta™ liquid scintillation counter at 40-50% efficiency. All determinations were in triplicate.
Calculations
Specific binding (C) to the membrane is the difference between total binding in the samples containing vehicle only and membrane (A) and non-specific binding in the samples containing the membrane and cytisine (B), i.e.,
Specific binding=( C )=( A )−( B ).
Specific binding in the presence of the test compound (E) is the difference between the total binding in the presence of the test compound (D) and non-specific binding (B), i.e., (E)=(D)−(B).
% Inhibition=(1−(( E )/( C ))times 100.
The compounds of the invention that were tested in the above assay exhibited IC 50 values of less than 10 μM. | This invention is directed to compounds of the formula (I):
and their pharmaceutically acceptable salts, wherein R 1 , R 2 , and R 3 are as defined herein; intermediates for the synthesis of such compounds, pharmaceutical compositions containing such compounds; and methods of using such compounds in the treatment of nicotine addiction/withdrawal and CNS disorders. | 2 |
This is a continuation of application Ser. No. 394,692, filed Sept. 6, 1973.
BACKGROUND OF THE INVENTION
This invention generally pertains to bearing members adapted to support beams or decks upon piers, foundations, sills, etc., and more particularly pertains to an improved elastomeric bearing structure which, solely through compressive and shear strain or deformation, will accommodate imposed static and dynamic loading, thermal movement, non-parallel loading and the like.
In the construction of large structures, such as a bridge or a building, an important factor which must be taken into consideration is the movement of the individual structural members relative to one another. Such movement can be due to a number of factors, such as the thermal expansion and contraction of the materials being used and also external forces, such as wind, earth movement and the like on the structure along with the static and dynamic loads applied to the members themselves. In a bridge structure, horizontal beams are suspended between spaced vertical supports with the ends of the beams terminating at the supports. In such an application, it is necessary that provision be made for the thermal expansion and contraction of each beam as well as the angular or rotational movement caused by beam deflection from traffic loads on the bridge. The present invention, as herein disclosed, comprises an improved elastomeric bearing for such applications.
The basic concept of supporting bridge beams or the like by means of load bearing elastomeric material is a pertinent application of elastomers as a structural material. The applied unit loads and various movements are compatible with the load bearing and elastic characteristics of the material, while design and fabrication requirements fall readily into accepted practices in the rubber industry. Beam movements are accommodated by rubber deformation, not relative motion. It has been proven that elastomeric bearings may effectively support the various reactions and accommodate the required movements of structures within the load bearing and elastic properties of the material. Considerable cost advantages are obtained and the necessity is eliminated for design of expensive moving parts and their subsequent maintenance.
The design of an elastomeric bearing begins with the understanding that a rubber compression spring is a device by which the gravity forces of a structure are to be balanced by the "memory" of a specific elastomeric compound or its capability to regain its original form. Rubber has this ability to deform and comply to extreme load conditions, and will predictably resist the resulting stress and return to normal upon release of the load.
Toward this end, extensive research has been devoted to study the load deformation characteristics of load bearing rubber. Because it is a complex material, designing to ultimate limits is also somewhat complex. Keeping the spring concept in mind, bearing design is begun on the simple premise that the less the compound has to deform or remember, the better and longer it can function properly. Keeping initial compression deflection and deformation within limits which are low enough to insure against further deformation, or settling, during the life of the structure, becomes the principle ruling criteria.
Probably the most important characteristic of rubber that makes it suitable for use in bridge bearings is the relative ease with which its compression modulus can be altered to meet the designer's needs. The compressive modulus is highly dependent upon the geometrical confinement of the rubber, which has been characterized by the term "Shape Factor" and is defined as the ratio of the effective bearing area under load to the exposed area free to bulge as a result of rubber displacement.
For example, if a bearing receives 500 p.s.i. dead load, and the rubber thickness is such that the perimeter surface area free to bulge is equal to the load area (shape factor of 1), the bearing will compress about 30% of its thickness immediately upon placement of the beam, and with time, will continue to creep or bulge out the sides. However, if the rubber thickness is reduced until this bulge area is only one-sixth the load area (shape factor of 6), deformation will then be less than 5% of thickness and subsequent creep or progressive deformation well be inconsequential or non-existent.
It should be noted, that in shape factors above 6, durometer change has no significant effect upon compressive deflection; a valid indication that a degree of rubber confinement has been reached where compression stability is permanent. This shape factor versus compression strain relationship, therefore, is simply a precise statement of the correct degree of rubber confinement required for the load ranges involved.
To summarize these load bearing design procedures, two principal controls are used: (1) a correct number of square inches in the plan area to support a given load, and (2) an effective thickness allowed for bulge which is correctly proportioned to the plan area in order to eliminate failure from settling or permanent deformation.
It should be noted that the shape factor effect assumes that bearings are restricted from any lateral movement between load surfaces by way of chemically bonding the elastomer to sole plates or having the elastomer in contact with a rough surface exhibiting a high frictional coefficient, such as concrete and the like. A simple unbonded bearing will function satisfactorily only if the load surfaces are permanently clean and dry and no outward surface creep between the load surfaces and the surfaces of the bearing is possible. In terms of functional longevity, the compression or settling life of an unbonded bearing depends substantially on the ability of the coefficient of friction between the bearing and the beam to be sufficiently high to prevent spreading. In applications of the present invention, there is intended to be substantially no slippage or creep between surfaces of the elastomeric body surfaces and the loading surfaces when reliance is placed on frictional engagement.
Designing the bearing to accommodate the various movements of the beam is a matter of selecting the thickness as a function of the amount of lateral movement anticipated. This comparison is necessary to determine. the shear strain in the rubber. In order to minimize high shear loads being transmitted to the pier or foundation, the elastomeric mass should not be extended laterally more than 25% of its thickness each way while under load, for example, as an empirically sound design rule.
As known, the rubber mass moves equally well in any direction. Since allowable shear travel will be 0-25%, for example, total allowable movement is half the thickness of the bearing. Conversely, the bearing thickness must be twice the expected total movement. Although it is unlikely that beams will be installed at temperatures representing the exact midpoint of their expansion, any additional strain or deformation should fall well below the ultimate permissable shear strain.
Assume that a beam or deck proves to have a potential horizontal movement equal to the thickness of the rubber. The basic bearing of a selected shape factor then provides only half the required travel capacity because of its thickness. In the prior art, another identical bearing has been positioned on top to gain the required thickness and both are bonded to a common steel plate at their common load surfaces. This double bearing still has the same load carrying capacity as the single basic bearing, but the accumulated lateral travel capacity of the two bearings now equals the expected beam movement. However, the common steel plate adds thickness to the composite bearing which does not contribute to such lateral travel capacity as permitted by the present invention.
The flexural or bending of beams under load causes a rotating movement of the upper surface of the bearing. The rotating load effect on the rubber is different from the effect of vertical dead beam load for several reasons. Dead load compression, evenly applied, causes transfer of rubber mass into the side bulge volume. The live rotating load causes an increase in bulge on that side of the bearing facing the beam length with a corresponding reduction on the opposite face. The actual difference in effect on the rubber is a uniform outward mass movement in the case of dead load and a non uniform mass transfer during bearing rotation.
Still another load effect is due to permanent non-parallelism of load surfaces. In this instance, side transfer is permanent and, over a fairly wide latitude, does not materially reduce the load carrying capacity of the bearing. While rubber has the ability to conform to a new permanent working position, care must be used not to exceed the "memory" of the compound.
DESCRIPTION OF THE PRIOR ART
The present invention is an improvement to structures such as disclosed in German Pat. No. 1,179,978, published Oct. 22, 1964. Related U.S. Pat. Nos. 3,504,905, 3,514,165 and 3,544,415 disclose laminated structures of elastomer and metal bonded together which serves to give a high shape factor for loads in compression and to utilize the accumulative lateral or shear deformation of successive layers of rubber.
Information concerning application of elastomers is found in publications respectively entitled NATURAL RUBBER IN BRIDGE BEARINGS (Bulletin No. 7) and ENGINEERING DESIGN WITH NATURAL RUBBER (Third Edition 1970) both published by the Natural Rubber Producers Research Association, 19 Buckingham Street, London W.C. 2., England. The foregoing publications including the patents will serve as references to provide additional information concerning the following detailed description.
SUMMARY OF THE INVENTION
The present invention provides an improved elastomeric bearing structure having a high shape factor, yet with a high shear displacement relative to the thickness of the structure.
The present invention also provides an improved elastomeric bearing structure wherein essentially the entire effective height, and substantially the entire volume of the bearing, is rubber which is adapted for maximum lateral deformation with optimum pressure distribution of vertical and horizontal loading.
The present invention further provides an improved elastomeric bearing structure which may be fabricated more simply and at less expense than prior art structures.
The present invention further provides an improved elastomeric bearing structure of simple design and of less weight for a given load application and installation space requirement.
The foregoing and other provisions and advantages are accomplished with an elastomeric bearing structure including a monolithic elastomeric support body defining a lower surface and an upper surface adapted to support a load in a structure and defining a peripheral edge about the perimeters of the lower and upper surfaces. A plurality of tension support members such as rods or rings are disposed in continuous confining relation about the peripheral surface and embedded in the peripheral edge. Adjacent tension support members are provided or different peripheral lengths or diameters and accordingly are disposed in both offset or staggered relationship and in vertically spaced apart relationship above one another within the support body. An elastomeric sheath may be disposed in bonded weather protective relation over the peripheral edge surface and tension support members. The tension support members are adapted to divide the peripheral surface into selected smaller areas subject to bulging when a compressive load is exerted on the lower and upper surfaces of the support body. The accumulative vertical dimensions of the tension support members should be in the order of not less than about 40% of the total thickness of the support body. The support body may include a central body bounded by an elastomeric retaining body disposed in bonded relationship about the periphery of said central body and between the central body and the tension support members. In such case the tension support members are embedded in the outer edge of the retaining body. The retaining body confines the support body to transmit forces from a compressive load on the central body through the central body to the retaining body. The retaining body is confined in turn by the tension support members. The bearing structure may comprise a plurality of the support bodies as described which are joined in cooperative disposition through connection with a spanning member. Sole plates may be provided in bonded relation to the upper and/or lower surfaces of the bearing structure as appropriate.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings,
FIG. 1 is a partly cut-away plan view of the elastomeric bearing of the present invention as viewed along the line 1--1 of FIG. 2;
FIG. 2 is a sectional and elevational view of an installation of the elastomeric bearing of the present invention, including a sectional view of the bearing taken at line 2--2 of FIG. 1;
FIG. 3 is a partially cut-away plan view of an alternate embodiment of elastomeric bearing of the present invention;
FIG. 4 is a sectional view taken at line 4--4 of FIG. 3;
FIG. 5 is a detailed sectional view of one embodiment of the invention taken at line 5--5 of FIGS. 1 and 3;
FIG. 6 is an alternate embodiment of the structure shown in FIG. 5;
FIG. 7 is another embodiment of the structure shown in FIG. 6; and
FIG. 8 is a further modification of the embodiment shown in FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As a brief definition of terms used herein, the inextensible tension support members may also be termed rings, rods, or the like. Elastomer and rubber as used herein are used interchangeably to denote appropriate synthetic or natural rubbers. Like elements in the different embodiments disclosed are identified with the same numbers.
Referring to FIGS. 1 and 2, there is shown an elastomeric bearing structure 10 incorporated in load bearing relation and supporting a beam or deck 12 from a pier or foundation 14. Bearing structure 10 essentially comprises an elastomeric support body 16 retained or confined as shown by a plurality of tension support members 18. As understood and clearly shown in FIGS. 2 and 4-8, the tension support rings are embodied of metal in order to be substantially inextensible or unstretchable.
Bearing structure 10 is shown as being generally of inverted frusto-conical shape. Body 16 defines a lower surface or face 20 and an upper surface or face 22 bounded at their edges by a peripheral edge or surface 24. The rings 18 are shown as being completely embedded in the rubber body 16 about its peripheral edge 24. The rings or hoops 18 are disposed within the body as shown not only to create a more monolithic structure, but also to dispose the rings in vertically offset or staggered relationship as will become evident.
FIG. 5 depicts a cross section of the bearing structure 10 taken at 5--5 of FIG. 1 and FIG. 3. As shown, the support rings 18 are disposed in the peripheral face 24 so as to leave selected areas for the rubber to bulge between adjacent rings 18 and a smaller selected distance between a designated ring and the upper or lower face of body 16. FIGS. 5--8 all illustrate exemplary vertical spacing for rings 18.
A basic concept herein is to substantially restrict the radial displacement over a large percentage of the rubber thickness (40% or more) when it is subjected to a compression load without appreciably affecting the shear strain characteristics. For example, FIGS. 1, 2 and 5-8 show the basic construction, which consists of a plurality of stress rings 18 which essentially encircle an elastomeric body. The summation of the cross sectional diameters of rings 18 should equal or exceed 0.4 of the thickness of support body 16.
When a compression load is applied to the bearing 10, the elastomer will tend to act as an incompressible fluid and exert forces in all directions. As a compression load is applied, a reduction in bearing height will result. Since elastomers are essentially incompressible, the reduction in bearing height forces the rubber body to extend radially. The elastomer located in the areas confined by the rings cannot displace radially since the rings 18 inhibit movement in that direction and is thus forced to displace into the nonrestricted areas between the rings.
However, the change in shape is also exerting forces which are trying to radially displace the elastomer but which inteferes with the tendency of the elastomer to freely enter the nonrestricted zones. The result of this configuration substantially reduces the amount of height reduction of body 16 under a given compression load. Whereas the shortest fiber length will be equal to the bearing thickness which is the longest possible for a given size bearing it is known that the fiber length is indirectly proportional to the shear load required to effect a shear strain rated as a percentage of such thickness i.e. the longer the fiber, the less shear load required for a given shear strain.
Other features are:
The body of the bearing is to be molded from a monolithic elastomer having good low temperature shear characteristics such as natural rubber, for example.
The exposed surface of the bearing is to be molded from an elastomer having good weathering, ozone and oil resistance characteristics such as neoprene.
The unrestricted rubber layer between faces 20 and 22 and the nearest respective ring 18 will be substantiallly less in thickness than the internal unrestricted layers between adjacent rings 18 to prevent "scrubbing" due to radial displacement.
A bearing may be molded as a short cylindrical column (FIGS. 6-8) in lieu of a frustum of a right circular cone (FIGS. 2 and 5). This would involve the use of stress rings of unequal outside diameters.
A bearing may be molded incorporating multiples of the basic bearing in combination, (for example as shown in FIG. 3) which would allow the bearing to be placed on a rectangular bearing seat which are most commonly used and reduce the magnitude of the hoop tension of the respective rings of the multiple combination for a given compressive load as compared to one of the larger rings of a larger basic bearing as described.
A bearing would be molded having some of the rings 18 unequal in outside diameter which would give a staggered or offset ring configuration (FIGS. 5-8) which would allow additional bearing rotation without excessive localized compression stress between the rings. Also, the offset or staggered configuration of rings 18 would permit the rings to be of selected larger cross-sectional diameter, giving a larger total accumulative ring height relative to total thickness of body 16 to provide substantially greater confinement and corresponding unit loading with substantially undiminished capability for movement in lateral shear.
The different embodiments disclosed and their variations may be molded with either or both of faces 20 or 22 bounded to a sole plate and the number and diameter of rings 18 provided may vary to fulfill shear movement requirement, unit loading, rotational requirement and shape factor.
The function of the rings 18 is to effectively increase the shape factor S of bearing structure 10 by dividing the peripheral area of edge 24 into smaller discrete areas subject to bulge while the area of surface 22, subject to vertical loading, remains constant. Concurrently, the total thickness of support body 16 effectively remains available for deflection in lateral shear. If prior art type laminations of plates of the same thickness as the diameter or accumulative height of rings 18 were substituted in lieu of rings 18, then the increase in shape factor would be substantially the same but the thickness and volume of rubber available for lateral shear equivalent to plate thickness would be lost.
As shown in FIGS. 1, 2 and 5 and previously mentioned, bearing 10 is formed in the shape of a truncated cone with parallel faces 20 and 22 and by the tapered edge or surface 24. As later discribed with reference to FIGS. 6-8, bearing 10 may also be provided in the shape of a short cylinder with the edge 24 being disposed perpendicular to the faces 20 and 22. The embodiment of FIGS. 1, 2 and 5 illustrates a structure which provides a constant load carrying area of elastomer equivalent to the area of surface 20 throughout the permissable lateral shear deflection of bearing 10 as caused by lateral movement of the beam 12. FIGS. 1 and 5 show dashed lines indicative of the position and shape attained by bearing 10 through a shear displacement distance S s . The distance S s indicates the designated movement in shear provided by the angle of taper of edge 24 to bring a portion of edge 24 to a posture which is perpendicular to faces 20 and 22 when the maximum permitted lateral movement is attained.
Each ring 18 is shown in FIGS. 2 and 5 to be embedded in the face 24 in vertically displaced apart and laterally offset relation with respect with each adjacent ring. In this embodiment the offset relation of the rings conveniently conform to the profile of the tapered surface of edge 24. More significantly, the effective lateral unconfined bulge area between adjacent rings may be reduced while the effective distance between the rings remain at an optimum to permit maximum rotational deflection within the bearing as caused by deflection of a supported beam 12, for example, and also to permit substantially uninhibited lateral movement in shear or body 16 commensurate with the full thickness of the rubber mass.
Though several kinds of natural and synthetic rubber may be provided for support body 16, a natural rubber of 40-50 durometer hardness is recommended, for example. The reason that natural rubber is preferred is that natural rubber has the most consistent shear modulus with various changes of temperature, as compared with some of the synthetic rubbers which exhibit a marked increase in shear modulus with comparable decreases in temperature.
Since natural rubber is less ozone resistant and more prone to deterioration from weathering, a protective sheath 28 (FIGS. 1-8) may be provided which is bonded to surface 24. The preferred material for sheath 20 is neoprene, selected for its superior ozone and weathering resistance. Other protective materials may be provided, however, such as certain grades of butyl rubbers, ehtylene polypropylene rubbers, polysulfide rubbers, silicone rubber and the like as dictated by effectiveness vs. price.
The embodiment of FIG. 5 is illustrated as being provided with three rings 18 disposed in both vertically spaced apart and laterally offset relation as shown. However, it is evident that the benefits of this invention may be attained by providing two or more of such rings disposed in vertically spaced apart and laterally offset or staggered relation, the number provided being dependent upon the cross-sectional diameters of each ring, the expected rotational and lateral movement to be imposed on body 16, the shape factor desired and related loading conditions.
FIG. 6 illustrates an alternate embodiment of the structure shown in FIGS. 2 and 5. In this embodiment the peripheral edge 24 is provided perpendicular to the surfaces 20 and 22. Three rings 18 are disposed in embedded relation about the edge 24 with each ring 18 being disposed both in vertically spaced apart and laterally staggered relationship relative to an adjacent ring or rings 18 as shown. The upper and lower rings 18 are of greater diameter or peripheral length than the center ring and consequently are disposed closer to edge 24 than the center ring. The upper and lower rings 18 are also disposed close to surfaces 20 and 22 respectively to prevent "scrubbing", as previously mentioned, when no sole plates are provided. The accumulative cross-sectional height of the rings 18 is shown as being not less than about 40% of the total thickness of body 16. Routine tests conducted with a selected elastomer for body 16 and with the support rings 18 being selected cross-sectional height and being disposed in selected vertical and lateral spaced apart relationship can result in an accumulative height of the rings 18 being somewhat greater or less than 40%, depending on a desired rating of structure 10 for vertical loading, lateral displacement, rotational requirement and/or shape factor. It is to be seen that the lateral distance between adjacent rings will permit vertical compression strain of body 16 without direct decrease in the effective distance between adjacent rings through the vertical decrease in distance between adjacent rings will be linear with such compressive strain.
As with the embodiment of FIG. 5, the body 16 of FIG. 6 may be provided with a protective sheath 28 bonded about the surface of edge 24 as shown.
FIG. 7 depicts an embodiment similar to that of FIG. 6 with the difference being that the center ring 18 is provided of greater peripheral diameter than the adjacent rings and accordingly is closer to edge 24. This embodiment will function substantially the same as the embodiments of FIGS. 5 and 6 when supporting the beam 12 through vertical loading, horizontal or lateral deflection and/or deflectional rotation of the beam as previously mentioned. When a beam 12 is supported from a pier 14 by any of the embodiments of bearing 10 as shown in FIGS. 5-7, the bearing 10 is considered to provide a "floating" type of support for a beam 12 which will support the vertical loading from the beam 12 and also accommodate the various horizontal and rotational movements of the beam.
FIG. 8 differs from the embodiments of FIG. 6 by the provision of support body 16 including a central body surrounded by a peripheral elastomeric retaining body 26. When provided as shown, the bulging action of retaining body 26 replaces the bulging action of the rubber central body of support body 16. Retaining body 26, as preferably provided, will be in the range of 50-60 durometer or a suitable range of greater hardness which is more resistant to deformation than the central body of support body 16. When the retaining body 26 is provided as shown, the bearing structure 10 is capable of handling greater loads since the harder rubber requires more applied force to bulge out between the rings 18.
When the bearing structure 10 is under a loaded condition such as depicted in FIG. 2, the elastomeric body 16, particularly near the center, behaves as a semiperfect liquid transferring vertical loading stresses to lateral stresses tending to cause the periphery of the member to bulge, as previously described. As shown in FIG. 8, the peripheral retaining body 26 acts as a "dam", confining the elastomeric body 16 and transmitting its force into bulges of the harder material between the rings 18. This arrangement provides increased vertical loading capacity. However, the resistance of the element 26 to lateral forces creating stresses in shear of the bearing structure 10 as a whole is not sufficient to be appreicable or undesirable.
The ghost lines in FIGS. 3, 4, 5 and 8 are to illustrate the optional upper sole plate 32 and/or an optional lower sole plate 30. When such sole plates are provided, they are firmly bonded to the rubber and fillet (not shown) is provided at the outer intersection of the rubber to the plate to minimize stress risers when the plates place the rubber in shear, compression or rotation. The purpose of the plates is for welding, bolting, or otherwise attaching the upper plate 30 to beam 12 when beam 12 is provided of metal rather than concrete as shown. Lower plate 30 is likewise provided for immovable attachment to pier 14 if the pier provided of steel or otherwise presenting a low friction coefficient to bearing structure 10.
It is pointed out that variations of the elements shown in FIGS. 4-8, such as sole plates 30 and 32, protective sheath 28, retaining body 26, and the number of rings 18 may be varied and combined as desired for a particular design and environmental condition, all within the purview of the present invention. It is also to be noted that retaining body 26 and sheath 28 may be combined as a common body formed of neoprene or the like as desired.
FIGS. 3 and 4 depict another embodiment of the invention wherein two of the bearing structures 10 are combined with a connecting elastomeric spanning member 34. The structure of FIG. 3 behaves substantially as described for the structure of FIGS. 1 and 2, but is shown to illustrate that more than one of the bearing structures 10 may be utilized in combination. Additional bearing structures 10 may be arranged in desired goemetric relation depending on the size and shape of beams such as 12 to be supported and available support area on piers or foundations 14. For example, three of the bodies 16 may be combined to provide a bearing 10 of generally triangular configuration. Four bodies 10 may be combined for a bearing 10 of square configuration. Six bodies 10 may be combined for a larger triangular or rectangular configuration and so on.
Bearing 10 has been described as frusto-conical or disc shaped with tension support members or rings 18 being circular in configuration. It is apparent that rings 18 would be urged to become circular upon application of loading force to bearing 10 which would place rings 18 under hoop stress as the elastomer body 16 seeks to deform under compression. However, rings 18 may have initial configurations other than exactly circular. For example, rings 18 may be provided of elliptical shape (not shown). When so provided, the minor diameter of the ellipse so formed may be restrained in shape by means of a tie rod or bar (not shown) connected to each ring 18 across the minor diameter.
It is also noted that corresponding rings 18 of adjacent bodies 16, such as shown in FIG. 3, might be a single ring or hoop formed in the shape of a figure "8" approximately as shown and joined at its waist with a tie rod or other appropriate connection.
The foregoing description and drawing will suggest other embodiments and variations to those skilled in the art, all of which are intended to be included in the spirit of the invention as set forth herein. | An improved elastomeric bearing structure adapted for use to support members such as beams or decks upon piers, foundations, sills, etc., to accommodate static and dynamic loading, thermal movement, non-parallel surfaces or rotation caused by beam deflection and the like. Bearing structure includes a monolithic elastomeric member which defines two substantially parallel side surfaces bounded at their peripheries by a curvilinear edge surface; the elastomeric member is confined at its edge surface by a plurality of elongated inextensible tension members disposed in both vertically spaced apart relation and horizontally offset or staggered relation and of selected accumulative height to allow selected adjacent areas of the edge surface to remain unconfined. Such structure permits a substantial increase in horizontal shear deflection for a bearing of specified thickness while also permitting superior accommodation to rotation caused by beam deflection and limiting deflection caused by vertical loading. | 4 |
FIELD OF THE INVENTION
The field of the invention relates generally to powered lift devices, particularly to powered hunting tree stands, and more particularly to portable hunting tree stands.
BACKGROUND OF THE INVENTION
Tree stands are well known hunting devices used to elevate one or more hunters to allow them a wider range of vision over the area in which they are hunting. One problem associated with tree stands in general is that they require the user, typically a hunter with a weapon, to physically climb up from the ground onto the tree stand platform. This can be an awkward task as the hunter is most likely carrying a weapon such as a rifle, shotgun, or bow and arrow as well as one or more food and drink containers. More importantly, hunters who are disabled to the point where physically climbing up into or down from a tree stand is either extremely difficult or impossible, are deprived of an important and enjoyable part of the hunting experience.
One other important problem of tree stands in the prior art is that they are often permanent structures. Because elevated tree stands are typically placed in trees or permanent structures, they are difficult to easily move from one location to another. Consequently, they are often left in place and exposed to weathering and other destructive effects that eventually lead to the deterioration of the tree stand.
The prior art contains examples of mechanized tree stands and powered lifts. U.S. patent application Nos. 2004/0083660 to Atkins, 2003/0000769 to Pyle, 2002/0139613 to Hardy are examples of recent publications disclosing portable and elevating hunting stands. Also included in this group is U.S. Pat. No. 5,862,827 to Howze. While the devices disclosed in these publications are all portable and capable of mechanized elevation, in each case the user must climb a ladder to reach the elevated platform. Thus, even though the platforms disclosed can be elevated, they provide no benefit to either a disabled hunter or one overly burdened with equipment who is attempting to climb into the platform.
U.S. patent application No. 2003/0178251 to Hewitt and U.S. Pat. No. 6,471,269 to Payne, U.S. Pat. No. 5,803,694 to Steele, U.S. Pat. No. 4,602,698 to Grant disclose tree stands which provide mechanized elevation for the user. In addition, U.S. Pat. No. 3,681,565 to Fisher discloses a suspended welding booth which mechanically raises the welder to a suspended position against a wall or other vertical structure. However, a review of these publications reveals an additional problem, namely the stability of the suspended platform. In each publication, the suspended platform, chair or booth is lifted off the ground and depends solely on the structural stability of a suspension system for safe support rather than using the actual ground as a foundation to support the elevated user.
U.S. Pat. Nos. 2,943,708 to Sasgen and U.S. Pat. No. 4,183,423 to Lewis both disclose mechanized hoists that remain placed on the ground or floor. However, both have the lift mechanism positioned off the elevating platform requiring someone other than the rider to raise and lower the platform. U.S. Pat. No. 5,595,265 to Lebroquy discloses a powered vertical lift but its configuration severely limits the height to which the lift may ascend. In addition, it fails to provide lateral stability to the suspended lift.
Therefore, there is a need in the field for a portable powered tree stand that is easily maneuverable, provides mechanized elevation to the user, and provides stability to a platform when it is the raised position.
SUMMARY OF THE INVENTION
The present invention comprises a powered lift platform that includes a platform, at least one guide rail section in operative contact with the platform, each of the at least one guide rail sections comprising at least one guide rail and in which a first end of each of the guide rail sections is configured to removably attach to a second end of a second guide rail section, a lift mechanism supported by the platform, a lift guide in operative contact with the lift mechanism and attached to the upper portion of the upper guide rail, a power supply to operate the lift mechanism. In a preferred embodiment, at least one wheel is operatively attached to the powered lift platform. The present invention further comprises a method of securing the powered lift platform to a vertical or sloping support. The present invention also includes an extendable standoff to adjustably support a device against a vertical or sloping support.
An object of the invention is to provide a powered or mechanized lift operated by a user positioned on the platform.
A second object of the invention is to provide a powered lift platform that is positioned on the ground or floor.
A third object of the invention is to provide a powered lift platform with lateral stability when elevated off the ground.
An additional object of the invention is to provide a powered lift platform in which the user may remain on the platform to secure the device to a vertical structure such as a tree or column.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The nature and mode of the operation of the present invention will now be more fully described in the following detailed description of the invention taken with the accompanying drawing Figures, in which:
FIG. 1 depicts a perspective view of the powered lift platform of the present invention;
FIG. 2 is a magnified perspective view of the lower slider adjustment of the present invention;
FIG. 2 a is a top view taken along line 2 A- 2 A of FIG. 2 showing the lower slider adjustment;
FIG. 3 is a magnified perspective view of the upper slider adjustment and cable break stop of the present invention;
FIG. 3 a is a top view of the upper slider adjustment and cable break stop of the present invention;
FIG. 3 b is a magnified perspective view of an alternate embodiment of the upper slide adjustment;
FIG. 3 c is a top view of the alternate embodiment of the upper slide adjustment;
FIG. 4 is a rear view of the powered lift platform of the present invention;
FIG. 4 a is a rear view of the powered lift platform depicting the activation of the cable break stop by the broken cable;
FIG. 4 b is a magnified side view of the adjustment assembly for the base plate of the present invention;
FIG. 5 is a side view of the powered lift platform of the present invention;
FIG. 5 a is a side view of the present invention in which the safety lock is activated;
FIG. 6 depicts an alternate embodiment of the lift guide used to lift the platform in the present invention;
FIG. 6 a is a magnified perspective view of the alternate lift guide seen in FIG. 6 ;
FIG. 7 demonstrates a second alternate embodiment of the lift guide for the powered lift platform of the present invention;
FIG. 7 a is a magnified perspective view of the second alternate lift guide for the powered lift platform of the present invention;
FIG. 8 is a top perspective view of the grippers of the present invention;
FIG. 8 a is an exploded top perspective view of the grippers of the present invention;
FIG. 9 is a side perspective view of the present invention attached to an upright support;
FIG. 10 is a side view of the present invention in a disassembled mode for towing;
FIG. 11 is a side perspective view of an alternate embodiment of the disassembled mode;
FIG. 12 is an exploded view of the assembly arrangement of the alternate disassembled mode; and,
FIG. 12 a is a side perspective view of the constructed assembly arrangement seen in FIG. 12 .
DETAILED DESCRIPTION OF THE INVENTION
At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical structural elements of the invention. While the present invention is described with respect to what is presently considered to be the preferred embodiments, it is understood that the invention is not limited to the disclosed embodiments. The present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Adverting to the drawings, FIG. 1 depicts a perspective view of powered lift platform 10 . Carriage 80 comprises the movable component of powered lift platform 10 and includes at a minimum platform 11 . Carriage 80 also includes other components found in various embodiments described and shown as attached directly or indirectly to platform 11 . Platform 11 is shown supporting power box 12 which houses a battery (not shown) and holds a battery switch 35 that is used as a power control. In a preferred embodiment, switch 35 is rotated in one direction to power platform 11 upward and rotated in the opposite direction to move platform 11 down. A suitable battery is a 12 volt all glass mat battery made by Universal Power Group. In addition, an AC inverter may be used. Preferably, a solar trickle charge device may be attached to the battery to constantly maintain battery charge when power lift platform 10 remains outdoors. In the preferred embodiment shown, seat 43 is supported by power box 12 . Also not shown in FIG. 1 is the housing for winch 32 which is secured to platform 11 and used to raise and lower platform 11 . Stop lever 28 includes safety stop blade 28 a and is also attached to a second safety stop blade 28 a (not shown in FIG. 1 ) by means of safety axle 30 . Stop lever 28 and safety stop blades 28 a are welded or otherwise securely attached to axle 30 as shown in FIGS. 3 and 3 a . Guide rails 13 are shown in operative attachment with platform 11 which is described in detail below and seen in FIGS. 2-3 c . By operative attachment or operative contact is meant the contacting of carriage 80 , platform 11 or a part of or a component of power lift platform 10 with guide rails 13 during at least a portion of the movement of platform 11 along guide rails 13 . Although a guide rail section having one guide rail 13 may be used to raise and lower platform 11 or carriage 80 , in the preferred mode shown in FIG. 1 , pairs of guide rails 13 comprise a guide rail section.
In a preferred embodiment, guide rails 13 are approximately 6 feet in length. In a more preferred embodiment, more than one set of guide rails is used to allow platform 11 to be pulled to a greater heights if desired. In the more preferred embodiment shown in FIG. 1 , guide rail inserts 14 can be inserted into guide rail sockets 15 to enable platform 11 to be moved efficiently up and down more than one section or set of attached guide rails 13 . Alternatively, sets of guide rails 13 can be bolted together or attached by alternate means well known in the art to enable them to be placed into an upright position.
In a preferred embodiment, guide rails 13 include attached standoffs or grippers 16 that rest against a vertical support such as a tree, lamp post, pole or other vertical support (not shown in FIG. 1 ). In a preferred embodiment, grippers 16 include teeth 17 to allow a more secure hold against vertical supports such as tree trunks. In a more preferred embodiment, gripper adjustments 18 are provided to extend or retract grippers 16 from or toward guide rails 13 . Use of gripper adjustment 18 allows guide rails 13 to be positioned in a more upright (nearly vertical) orientation even if the vertical support is itself in a comparatively more sloping (non-vertical) position.
Powered lift platform 10 is operated by a lift mechanism attached to platform 11 and placed in operative contact with a lift guide that provides lift support for the lift mechanism and/or lift guide for the lift mechanism. FIGS. 1 , 2 , 2 a , 4 , 4 a , 5 , and 5 a show one type of lift mechanism, namely winch 32 attached to platform 11 through winch frame 32 a . Cable 33 is attached to winch 32 and to cable anchor 21 at an anchor point preferably located at the top of the highest guide rail 13 and acts as the lift guide for winch 32 . The anchor point is defined as the location where the lift guide (cable 33 in the embodiment shown in FIG. 1 ) is secured to guide rail section 13 . In a preferred embodiment, a second cable anchor 21 a is placed on a lower guide rail 13 section to enable platform 11 to be raised sufficiently on lower guide rails 13 to allow the operator to more easily attach an additional guide rail section 13 to the lower guide rail 13 section. Platform 11 is transported along guide rails 13 as winch 32 winds or unwinds cable 33 . Preferably, winch 32 is operated from platform 11 using switch 35 as it is raises or lowers platform 11 along guide rails 13 . Switch 35 may be located on power box 12 and is connected to the battery and winch 32 . In an alternate embodiment, switch 35 and power cord 34 may be located proximate to the ground to allow the operator to remain on the ground while operating powered lift platform 10 . It will be recognized that in this alternate embodiment, switch 35 and power cord 34 may be a hand-held control used by the operator positioned on platform 11 .
Also shown in FIG. 1 are safety rails 44 which extend along the sides and front of platform 11 . In one embodiment, rails 44 comprise two sets of rails each possessing two risers supporting a crosspiece. Detachable front rail 44 a links the two sets of side rails. Base plates 23 are attached to the bottom of each of guide rail sections 13 and provide support for guide rail sections 13 against the ground.
FIG. 2 is a magnified perspective view of lower slide adjustment 27 . Bolt 27 is shown extending through lower lever arm 27 b . Lower press pad 27 c is attached to lower lever arm 27 b . Lower guide pad 27 d is attached to lower press pad 27 c . As bolt 27 is tightened, it draws lower guide pad 27 d (attached to lower press pad 27 c ) against the internal side of guide rail section 13 by pivoting lever arm 27 b around pivot point 27 a .Preferably, lower press pad 27 c is made from a metal such as is used in typical angle iron and lower guide pad 27 d is made from a plastic with some resilience such as Teflon to reduce the friction between lower guide pad 27 d and the internal side of guide rail 13 . Pivot point 27 a can be a bolt rod or similar device that is placed through lever arm 27 b as shown to allow it to pivot or rotate. Gap 36 is established between lower lever arm 27 b and winch frame 32 a using lower adjustment spacer 27 e to allow lower lever arm 27 b to rotate freely. Gap 36 is exaggerated in FIG. 2 for clarity. FIG. 2 a is a top view of lower slide adjustment 27 . Ultimately, this lower adjustment mechanism presses lower guide pad 27 d against guide rail 13 to help stabilize platform 11 against guide rails 13 as it is raised and lowered. Also seen in FIG. 2 are wheels 22 operatively attached to powered lift platform 10 . By operative attachment is meant that at least one wheel 22 is attached to powered lift platform 10 to allow it to be towed or otherwise moved using a wheel, tire or equivalent device. In the embodiment shown, two wheels 22 are attached to guide rails 13 by means of wheel attachments 22 a . In an alternate embodiment, wheels 22 may be attached to platform 11 . FIG. 2 also shows base plate prong 23 a which is positioned into the ground to further support power lift platform 10 .
FIG. 3 is a magnified perspective view of upper slide adjustment 26 . In this preferred embodiment, the head of bolt 26 is placed between upper lever arm 26 b and cable stop frame 37 a and extends through cable stop frame 37 a . In the embodiment shown, cable stop frame 37 a is threaded. In an alternate embodiment, a nut is secured to cable stop frame 37 a to secure bolt 26 . As bolt 26 is tightened or loosened, it decreases or increases pressure onto upper press pad 26 c , attached to upper lever arm 26 b and upper guide pad 26 d , attached to upper press pad 26 c . Ultimately, this enables pressure to be applied through upper guide pad 26 d against the internal surface of guide rail 13 . In this preferred embodiment, the end opposite the head of bolt 26 extends through cable stop frame 37 a and is not “mushroomed” by pressing against upper press pad 26 c . It should be recognized that this preferred embodiment can be used for the lower slide adjustment 27 and that the arrangement described above for lower slide adjustment 27 can be used for upper slide adjustment 26 .
FIG. 3 a , taken along line 3 a - 3 a in FIG. 3 , is a top view of upper slider adjustment 26 . Similar to lower slide adjustment 27 described above, upper press pad 26 c may be made from angle iron while upper guide pad 26 d is made from a plastic such as Teflon to reduce friction with the internal surface of guide rail 13 .
FIG. 3 b shows depicts an alternate embodiment in which upper guide pad 26 d is replaced by bearings 26 f . Bearings 26 f are biased against the internal surface of guide rail section 13 to reduce friction between platform 11 and guide rail section 13 as platform 11 moves along the guide rail section 13 . Bearings 26 f may also be used in lower slide adjustment 27 . FIG. 3 c is a top view of the embodiment seen in FIG. 3 b.
Also shown in FIGS. 3 and 3 a is cable break stop 31 . Cable break stop 31 is attached to cable stop frame 37 a at pivot 38 and is functionally associated with cable 33 . By functional association is meant that the position of cable break stop 31 in relation to platform 11 and lock stop 19 or ladder step 20 is dependent on whether cable 33 is intact (or taut) or broken (or slack) as described below. When cable rest 39 of cable break stop 31 contacts cable 33 above pivot 38 , cable break stop 31 has insufficient length to reach to ladder step 20 , but can extend to ladder step 20 when it rotates to a more horizontal orientation. During operation, cable 33 is arranged to contact cable rest 39 on the opposite side from pivot 38 and cable break stop 31 is orientated so cable rest 39 is rotated away from ladder step 20 . As winch 32 winds cable 33 , cable stop 40 prevents cable 33 from losing contact with cable rest 39 as winding cable 33 travels back and forth along the spool of winch 33 . Cable break stop 31 functions to stop platform 11 from falling should cable 33 break or become slack. In the situation when platform 11 is stopped and cable 33 becomes slack, cable break stop 31 continues to rest against cable 33 . As cable 33 becomes taut when platform 11 starts to move, the snapping action will tend to push cable break stop 31 away from cable 33 . Cable pivot stop 46 , preferably located over pivot 38 prevents cable break stop 31 from rotating too far and ensures the cable rest 39 contacts cable 33 .
FIG. 4 is a rear view of powered lift platform 10 depicting cable rest 39 (not shown in FIG. 4 ) of cable break stop 31 contacting cable 33 as platform 11 is being raised. FIG. 4 a demonstrates the action of cable break stop 31 after cable 33 breaks causing platform 11 to fall. In the event of such a break, while platform 11 falls, cable rest 39 will rotate until it contacts and rests against cable break frame 37 a thus preventing further rotation in that direction. Simultaneously, during the fall of platform 11 , the opposite end of cable break stop 31 rotates until it contact ladder step 20 (or lock stop 19 if cable break stop 31 is oriented toward the opposite side). Because cable break frame 37 a prevents rotation of the cable rest 39 end of cable break stop 31 and ladder step 20 prevents rotation of the opposite end of cable break stop 31 , platform 11 is prevented from falling by the wedged position of cable break stop 31 created during the fall. FIGS. 4 and 4 a also show paired lower slide adjustment 27 and paired upper slide adjustment 26 b each attached to opposite sides of platform 11 .
FIG. 4 b depicts an adjustment assembly for base plate 23 . Telescoping slide 23 b includes adjustment holes 23 d and moves within guide rail section 13 . To provide more level support for power lift platform 10 on uneven ground, telescoping slide 23 b of each guide rail section 13 can be separately adjusted by moving adjustment holes 23 d to a desired level and then securing them in place by pin 23 c which is inserted through a hole in guide rail section 13 and through an appropriate adjustment hole 23 d to provide a firm support for each base plate 23 whether on even or uneven ground. In one embodiment, adjustment holes 23 d are placed approximately one inch apart, but different distances may be used if desired.
FIG. 5 is a side view demonstrating the structure of safety stop lever 28 . Safety stop lever 28 and stop axle 30 pivot is seen in FIG. 3 to turn paired stop blades 28 a . Stop blocks 29 are positioned on each side of power box 12 to prevent complete rotation of stop lever 28 . Stop lever 28 functions as an emergency brake if platform 11 should unexpectedly fall. As platform 11 is raised up along guide rails 13 , stop blades 28 a contact the bottoms of safety stop 19 and ladder steps 20 located on opposite sides of guide rails 13 . The continued upward movement of platform 11 forces safety lever 28 , safety blades 28 a and axle 30 to rotate. After clearing safety block 19 and ladder step 20 , safety lever 28 rotates back to contact safety stop blocks 29 . It will be easily recognized that if the operator holds safety lever 28 up, safety blades 28 a rotate out of the contact path to prevent the intermittent contact with successive safety stops 19 and ladder steps 20 as platform 11 is raised or lowered. It will also be recognized that if platform 11 should fall, safety blades 28 a will contact the upper surface of either or both of safety stop 19 or ladder step 20 . Because safety block 29 is positioned in the rotational path of safety lever 28 , its presence prevents further rotation of safety blades 28 a off both safety stop 19 and ladder step 20 thus holding platform 11 and preventing the fall from continuing as seen in FIG. 5 a . Ladder steps 20 can also be used to climb down from platform 11 when it is stopped in a raised position off the ground.
FIGS. 5 and 5 a also show a preferred embodiment in which switch 60 is positioned preferably on carriage 80 . Carriage 80 is defined as the entire movable component of powered lift platform 10 that moves up and down guide rail section(s) 13 . Switch 60 is a type of normally open, normally closed switch such that when activated, it shuts off power to the up drive of winch 32 or other powered lift mechanism and maintains power to the down drive. Switch 60 is activated by actuator 61 (see FIG. 9 ) placed toward the top of upper guide rail section 13 so that as platform 11 reaches an upper limit (such as when cable 33 is wound almost completely onto winch 32 , switch 60 is activated by actuator 61 to prevent platform 11 from moving further up guide rail sections 13 and allows platform 11 to move only down guide rail sections 13 . In a more preferred embodiment, lower actuator 61 a is movably attached to the lowest guide rail section 13 to prevent platform 11 from being lifted too high before upper guide rail section 13 is attached. After attachment, lower actuator 61 a is moved away from the lift path by hinges or other means known in the art.
FIG. 6 depicts an alternate means of lifting platform 11 up and down along guide rails 13 . FIG. 6 shows gear-tooth rails 47 extending behind platform 11 which supports gear motor 48 (not shown in FIG. 6 ) and anchored at the top of guide rail section 13 . As seen in FIG. 6 a , gear motor 48 operates gears 49 to rotate them along gear-toothed rails 47 . Because gear motor 48 is attached to platform 11 , platform 11 is raised or lowered along gear-toothed rails 47 according to the direction of rotation of gears 49 Although two gear-tooth rails 47 are shown in FIG. 6 , it will be recognized that one or more than two gear-tooth rails 47 may be used although the use of only one gear tooth rail 47 is less preferred. Preferably, gear-toothed rails 47 are used with guide rails 13 although it will be recognized by those skilled in the art that gear-toothed rails 47 may replace guide rails 13 to supply both lift guide and lifting functions to powered lift platform 10 .
FIG. 7 demonstrates a second alternate embodiment of the lift mechanism for powered lift platform 10 . Helical carry rod 50 extends from a base or bottom transverse bar 45 to an anchor point 21 . FIG. 7 a shows ball screw mechanism 51 attached to platform 11 and operated by ball screw motor 52 to traverse up and down helical carry rod 50 thereby lifting platform 11 up and down along helical carry rod 50 . Mechanisms able to convert rotational movement to vertical movement are well known in the art.
FIG. 8 is a top perspective view of grippers 16 adjustably attached to guide rails 13 . As will be seen below, grippers 16 having at least one extension from guide rail section 13 are used to support powered lift platform 10 against an upright support such as a tree, pole, lamppost or similar device. In a preferred embodiment, gripper 16 includes teeth 17 and a pair of gripper extensions 18 c attached to the v-shaped gripper 16 and containing a plurality of position holes 18 d . In an alternate embodiment, gripper 16 may be U-shaped. Gripper 16 is arranged to extend from and retract into gripper adjustment sleeve 18 a . In operation, gripper 16 is pulled from gripper extensions 18 c and held in a desired position against an upright support by inserting gripper adjustment pin 18 b (“pin 18 b ”) through one of position holes 18 d and restraining hole 18 e . It will be recognized that each of the plurality of grippers 16 can be adjusted individually to establish a stable position for powered lift platform 10 even if the upright support is not straight or is at a sloping angle relative to the ground. In a preferred embodiment, transverse bar 45 extends between guide rails 13 to provide lateral rigidity between the paired guide rails 13
FIG. 9 shows power lift platform 10 supported against upright support 42 , in this case tree 42 . Straps 41 , preferably ratchet straps 41 , are seen wrapped around tree 42 and attached to both ends of transverse bar 45 . Powered lift platform 10 is supported substantially upright by placing base plates 23 as close to tree 42 as possible and positioning power lift platform 10 upright near or against tree 42 . Grippers 16 are extended to the desired length to produce a preferred vertical or near vertical position. After setting gripper 16 positions on lower guide rails 13 , ratchet straps 41 are wrapped around tree 42 , connected to gripper 16 , or preferably transverse bar 45 , and tightened. In a preferred embodiment, cable 33 is attached to lower cable anchor 21 a and platform 11 is raised to a desired height. A second set of guide rails 13 is attached to the first or bottom set of guide rails 13 by, for example, inserting guide rail inserts 14 into guide rail sockets 15 . The two sets of guide rails 13 may also be attached by bolts, hinges, or other suitable attachment devices known to those skilled in the art. Before attaching this second set, cable 33 is attached to cable anchor 21 . After attachment of upper guide rails 13 to lower guide rails 13 , winch 32 is operated to move platform 11 up guide rails 13 . At a suitable position(s), platform 11 is stopped, gripper 16 is adjusted and additional ratchet straps 41 are wrapped around tree 42 and attached at both ends of gripper 16 , or preferably transverse bar 45 , as shown in FIG. 9 . Once a sufficient number of grippers 16 are attached to tree 42 , powered lift platform 10 can be safely operated to move up and down the plurality of guide rails 13 .
FIG. 10 depicts powered lift platform 10 in a disassembled mode with two wheels 22 and two sets of guide rails 13 secured to each other and towed by an individual user. Alternately, a towing attachment may be used to tow powered lift platform 10 using such vehicles as all terrain vehicles, trucks, cars, or other suitable equipment. Hold down straps 70 are used to hold separate guide rails 13 components together and to hold safety rails 44 onto platform 11 . Ratchet straps 41 may be used as hold down straps.
FIGS. 11 , 12 and 12 a depict a preferred design of the disassembled mode in which safety stops 19 and ladder steps 20 of one guide rail section 13 align with grippers 16 of a second guide rail section 13 . FIG. 11 is a perspective view showing this preferred design. FIG. 12 is exploded view of this preferred embodiment in which ladder joiner 71 and safety stop joiner 72 each have a joining hole 71 a and 72 a , respectively. Ladder joiner 71 is inserted through ladder step 20 into gripper adjustment sleeve 18 a and is held in position with pin 71 b inserted through joining hole 71 a and ladder pin hole 71 c . Similarly, safety stop joiner 72 is inserted through safety stop 19 into gripper adjustment sleeve 18 a and is held in position with pin 72 b which extends through safety stop joining hole 72 a and safety stop pin hole 72 c . In this embodiment, the two guide rail sections 13 are then held securely in place by joining pins 71 b and 72 b.
Thus it is seen that the objects of the invention are efficiently obtained, although changes and modifications to the invention should be readily apparent to those having ordinary skill in the art, which changes would not depart from the spirit and scope of the invention as claimed.
10 powered lift platform 11 platform 12 power box 13 guide rails 14 guide rail inserts 15 guide rail sockets 16 gripper 17 gripper teeth 18 gripper adjustment 18 a gripper adjustment sleeve 18 b gripper adjustment pin 18 c gripper adjustment extension 18 d position hole 18 e attachment hole 19 safety stop 20 ladder step 21 cable anchor/anchor point 21 a lower cable anchor 22 wheels 22 a wheel attachment 23 base plate 23 a base plate prongs 23 b telescoping slide 23 c telescoping slide pin 23 d telescoping slide adjustment hole 26 upper slide adjustment/bolt 26 a upper adjustment pivot 26 b upper adjustment lever arm 26 c upper adjustment press pad 26 d upper adjustment guide pad 26 f bearing 27 lower slide adjustment/bolt 27 a lower adjustment pivot 27 b lower adjustment lever arm 27 c lower adjustment press pad 27 d lower adjustment guide pad 27 e lower adjustment spacer 28 safety stop lever 28 a safety stop blade 29 safety stop block 30 safety stop axle 31 cable break stop 32 winch 32 a winch frame 33 cable 33 a cable hook 34 power cord 35 switch 36 gap 37 cable stop frame 38 cable break stop pivot 39 cable rest 40 cable stop 41 ratchet straps 42 tree 43 seat 44 safety rails 44 a detachable front rail 45 transverse bar 46 cable pivot stop 47 gear-toothed lift rails 48 gear motor 49 gear 50 helical carry rod 51 ball screw mechanism 52 ball screw motor 60 switch 61 actuator 61 a lower actuator 70 strap 71 ladder joiner 71 a ladder joiner hole 71 b ladder joiner pin 71 c ladder pin hole 72 safety stop joiner 72 a safety stop joiner hole 72 b safety stop joiner pin 72 c safety stop pin hole | The present invention is a powered lift platform including a platform, at least one guide rail section in operative contact with the platform, each of the at least one guide rail sections comprising at least one guide rail and in which a first end of each of the guide rail sections is configured to removably attach to a second end of a second guide rail section. The invention also includes a lift mechanism supported by the platform, a lift guide in operative contact with the lift mechanism and attached to the upper portion of the upper guide rail, a power supply to operate the lift mechanism. In a preferred embodiment, at least one wheel is operatively attached to the powered lift platform. Also presented is a method for securing the powered lift platform to a columnar-like support. Also presented is an extendable standoff. | 0 |
This application is a continuation-in-part application of U.S. Ser. No. 718,284 filed Apr. 1, 1985, and now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a rotary compressor apparatus, and more particularly to a suction valve means incorporated in the rotary compressor apparatus including a rotary compressor of screw type or sliding vane type without feeding of the lubricating oil.
2. Description of the Prior Art
U.S. Pat. No. 4,035,114 discloses a rotary compressor apparatus in which the discharge pressure of gas compressed therein is used as an operating pressure for suction throttle valve means and in which a spring is provided for urging the suction throttle valve means to open it.
However, this type of rotary compressor apparatus would be faced with the following problems when it is started.
(1) When and immediately after the rotary compressor is started, its discharge pressure is somewhat positive or substantially null (i.e., equal to atmospheric pressure). Thus, it would be impossible to use the discharge pressure as the operating pressure for the suction throttle valve means.
(2) Since the operating pressure for the suction throttle valve means is somewhat positive or substantially null and the suction throttle valve means is always urged by the spring to be opened, the compressor would be started by a starter motor while the suction throttle valve means still remains open. The compressor is started at full load (100% load), so that an excess current is undesirably supplied to the starter motor.
In another type of rotary compressor apparatus, on the contrary, the suction throttle valve means is always urged by a spring to be closed. In this type of rotary compressor apparatus, the compressor is started at no load, however, it takes a long time to open the suction throttle valve means against the urging spring.
It has been proposed to provide a separate pressure source for the suction throttle valve means. However, this proposal would render the construction complex and increase costs because the separate pressure source requires an additional control unit therefore.
SUMMARY OF THE INVENTION
An object of this invention is to provide a rotary compressor apparatus in which a rotary compressor is capable if not only being started at no load or in substantially no load condition, but opening suction throttle valve means immediately after the compressor is started.
Another object is to provide a rotary compressor apparatus able to accomplish the above functions without a separate source of pressure for the suction throttle valve means.
Still another object is to provide a rotary compressor apparatus of simple construction capable of accomplishing the above objects.
To this end, the rotary compressor apparatus according to the invention comprises a rotary compressor, a suction valve means for regulating an amount of gas to be supplied to the compressor, a piston-cylinder unit for moving a valve element of the suction valve means to shift the suction valve means between an open position and a closed position, and means for opening the suction valve means immediately after the compressor is started.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram of the first embodiment of the invention;
FIG. 2 is a circuit diagram of the second embodiment of the invention;
FIGS. 3(a) and 3(b) are partially fragmentary sectional views showing the operations of the valve elements in the first and second embodiments;
FIG. 4 is a circuit diagram of the control circuit including a starter circuit for the rotary compressor units of FIGS. 1 and 2; and
FIG. 5 is a circuit diagram of a portion of another form of the invention wherein a plurality of on-off (one-way) valves are employed rather three-way valves as in the embodiments of FIGS. 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 showing the first embodiment, a compressor 1 comprises a suction line 1A in which a suction valve means 2 having a casing 2A and a valve element 2B is disposed. The valve casing 2A is provided with an inlet port 2Aa, an outlet port 2Ab and a passage 2Ac associated with the valve element 2B to control an amount of gas passing therethrough. The compressor 1 also comprises a discharge line 1B in which a cooler 4 for exhaust gas, a check valve 5, an after-cooler 6, an orifice (pressure regulating means) 7 and a pressure switch 8 are provided.
A piston-cylinder unit 9 is mounted onto the casing 2A of the suction valve means 2 and provided with a cylinder 9A having openings 9Aa-9Ad. The cylinder 9A incorporates therein a gas release valve element 9B for opening and closing the gas release opening 9Ac, a rod 9C provided at one end thereof with the valve element 9B, a rod 9D provided at one end thereof with the valve element 2B and an unloader piston 9E dividing a working chamber 9F into two chamber sections 9Fa and 9Fb. The other ends of the rods 9C and 9D are connected to the opposite ends of the piston 9E, respectively. The piston 9E is closely fitted to and movable within the cylinder 9A.
The opening 9Aa of the cylinder 9A is communicated with a discharge line section 1Ba of the discharge line 1B on the downstream side of the after-cooler 6 through a valve opening line 10, a first three-way solenoid valve 11 and an operation line 12. The opening 9Ab of the cylinder 9A is also communicated with the discharge line section 1Ba through a valve closing line 13 and a second three-way solenoid valve 14 and the operation line 12. The opening 9Ac of the cylinder 9A is communicated with a heat exchanger 4a within the cooler 4 through a exhaust gas line 15. The second three-way solenoid valve 14 is communicated with the outlet port 2Ab of the suction valve means 2 through a negative pressure communicating line 16. A chain line, a solid line and a broken line in the figures indicate flows of gas when the compressor is started and stopped, when a load is applied to the compressor and when a load is removed from the compressor, respectively.
The operation of the above described embodiment of the invention will be explained. When the compressor 1 is shut down, the second three-way solenoid valve 14 is so switched that the operation line 12 communicates with the valve closing line 13. The compressed air is introduced into one chamber section 9Fb of the working chamber 9F associated with the opening 9Ab therethrough, whereby the piston 9E is moved leftwardly in FIG. 1. The valve element 2B of the suction valve means 2 is also moved leftwardly to close the valve seat 2Ac. At the same time, the valve element 9B is moved leftwardly together with the piston 9E to open the opening 9Ac. Thus, the compressed air of high temperature and pressure in a line section of the discharge line 1B between the compressor 1 and the check valve 5 is cooled within the cooler 4 and then released into the atmosphere from an air releasing line 17 via the exhaust gas line 15 and the opening 9Ac.
As described hereinabove, before the compressor 1 is started, the suction valve means 2 is always maintained in a full closed position. Accordingly, the compressor can be started at no load condition. After the compressor 1 is started, the second solenoid valve 14 is so switched by means of an unloader timer 24, as discussed with respect to FIG. 4 below, that the valve closing line 13 communicates with the line 16. Accordingly, the outlet port 2Ab communicates with the one chamber section 9Fb of the working chamber 9F associated with the opening 9Ab. A negative pressure is applied to the port 2Ab and the one chamber section.
Since the valve element 2B is smaller in diameter thereof than the piston 9E, the piston 9E receives a higher load than the valve element 2B does. Meanwhile, when the first solenoid valve 11 is so switched that the operation line 12 communicates with the valve opening line 10, a low level pressure is introduced into the other chamber section 9Fa of the working chamber 9F associated with the opening 9Aa. The higher load as well as the low level pressure both noted hereinabove are applied to the piston 9E to move it rightwardly in the figure, so that the valve element 2B of the suction valve means 2 is moved together with the rod 9D away from the passage 2Ac to open the valve means 2. Therefore, the gas is introduced into the compressor 1 through the inlet port 2Aa and the outlet port 2Ab, and then the compressor 1 is to be operated in the full load condition, instead of the no load condition. Namely, in this embodiment, the compressor can be started in no load condition and operated in full load condition.
The compressor 1 is controlled in its displacement as follows. The pressure in the discharge line section 1Ba is detected by the pressure switch 8. The two solenoid valves 11 and 14 are suitably switched in accordance with the value of the sensed pressure to control the valve element 2B as explained below with reference to FIG. 4.
When the pressure in the discharge line 1Ba exceeds the predetermined (upper limit) value, the pressure switch 8 is switched to the "OFF" position. Consequently, the solenoid 14A of valve 14 is demagnetized by the signal from the control circuit 21, so that the line 12 communicates with the line 13. Simultaneously, the solenoid 11A of valve 11 is also demagnetized, so that the valve 11 communicates the line 10 to the atmosphere. Accordingly, the pressurized gas from the discharge line 1Ba flows into the chamber 9Fb through the line 12, the valve 14, the line 13 and the opening 9Ab. The pressurized gas moves the piston 9E leftwards (as viewed in FIGS. 1 and 2), so that the valve element 2B is moved to the valve seat 2Ac via rod 9D. Consequently, the suction valve means 2 is closed to change the compressor into the unload condition.
When the pressure in the discharge line 1Ba falls below the predetermined (lower limit) value according to the increasing of air consumption, the pressure switch 8 is switched to the "ON" position. Consequently, the solenoid 14A of valve 14 is magnetized by the signal from the control circuit 21, so that the valve 14 communicates the line 13 with the line 16. Simultaneously, the solenoid 11A of valve 11 is also magnetized so as to communicate the line 12 with the line 10. Accordingly, the pressurized gas in the discharge line 1Ba flows into the chamber 9Fa through the line 12, the valve 11, the line 10 and the opening 9Aa. The pressurized gas moves the piston 9E rightward (as viewed in FIGS. 1 and 2), so that the valve element 2B is moved apart from the passage 2Ac. Consequently, the suction valve means 2 is opened so as to change the compressor into a load condition.
FIG. 4 shows the control circuit 21 including a starter circuit. The three-phase supply is electrically connected to the motor for driving the compressor through a solenoid switch 22 for star-start, and a solenoid switch 23 for switching the star-connection to the delta-connection. In FIG. 4, the reference numeral 24 designates a timer, 22A designates a coil of the solenoid switch 22, 23A designates a coil of the solenoid switch 23, 25 designates a stop switch, 26 designates a start switch, and 24A and 24B designate contacts of the timer 24. The contact 24A is maintained in the "ON" position during a set time of the timer 24, and the contact 24B is switched to the "ON" position after lapse of the set time. The reference numeral 22B designates a contact associated with the solenoid switch 22, which is in the "OFF" position while the solenoid switch 22 is in the "ON" position, and which to the contrary, is in the "ON" position while the solenoid switch 22 is in the "OFF" position. The reference numeral 23B designates a contact associated with the solenoid switch 23, which is in the "OFF" position while the solenoid switch 23 is in the "ON" position, and which to the contrary, is in the "ON" position while the solenoid switch 23 is in the "OFF" position.
The reference numeral 23C is a contact associated with the solenoid switch 23 (or the timer 24), which is switched into the "ON" position when the solenoid switch 23 is switched into the "ON" position (or after lapse of the set time). The reference numeral 8A designates a contact of the pressure switch 8, which is in the "ON" position in a pressure lower than the predetermined value and is in the "OFF" position in a pressure higher than the predetermined value. When the start switch 26 is switched on, the solenoid switch 22 for star-start is switched to the "ON" position. After lapse of the timer set time (e.g., 15 sec.), the contacts 23B and 22B are switched into the "OFF" and "ON" positions respectively and then the solenoid switch 23 for switching the star-connection into the delta-connection is switched into "ON" position. Accordingly, the star-delta start is completed. On the other hand, the contact 23C is switched into the "ON" position when the solenoid switch 23 is switched into the "ON" position (after lapse of the timer set time), so that both of solenoids 11A and 14A of the valves 11 and 14 are switched into the "ON" positions.
Thus, the valve 14 cooperates with the timer 24 and the pressure switch 8. Namely, at start of the system, the pressure in the discharge line 1Ba is lower and then the pressure switch 8 is in the "ON" position. However, the "0FF" signal is delivered from the timer 24 to the second valve 14 so as to communicate the line 12 with the line 13. On the other hand, the first valve 11 also cooperates with the timer 24 and the pressure switch 8. At start of the system the pressure switch 8 is in the "ON" position by the same reason as the above one, and the "OFF" signal is delivered from the timer 24 to the first valve 11 so as to communicate the line 10 to the atmosphere. After lapse of the timer set time, the signal from the timer 24 is the "OFF" one and the signal from the pressure switch 8 is also the "OFF", so that the first valve 11 is switched to the "OFF" position. Consequently, the line 13 communicates with the line 16 and the first valve 11 is switched into the "OFF" position so as to communicate the line 12 with the line 10. Accordingly, the valve element 2B is moved apart from the valve seat 2C so as to change the compressor into a load condition. The chart below illustrates these relationships with respect to the operational modes of the rotary compressor.
__________________________________________________________________________ OPERATION MODE LOAD UNLOAD STARTING OPERATION OPERATION__________________________________________________________________________FIRST VALVE 11 OFF ON OFFSECOND VALVE 14 OFF ON OFFTIMER OFF ON ON (DURING SET TIME)PRESSURE SWITCH 8 ON ON OFF__________________________________________________________________________
FIG. 2 shows the second embodiment of the invention. The parts similar to those shown in FIG. 1 are designated by the same reference numerals and the explanation thereof is omitted.
In the figure, a solid line, a chain line and a broken line indicate the same air flows in FIG. 1, respectively.
The numeral 18 designates a balancing valve element mounted on a free end of an extension 9G of the rod 9D. The balancing valve element 18 is equal to or somewhat smaller in diameter thereof than the valve element 2B. The numeral 19 designates a balancing recess which receives the balancing valve element 18 and the numeral 20 designates a line providing a communication between the balancing recess 19 and the inlet port 2Aa.
The suction valve means 2 is disposed in the suction line 1A. The cooler 4, check valve 5 and the after-cooler 6 are sequentially disposed in the discharge line 1B. The orifice 7 shown in FIG. 1 is not provided in the discharge line section 1Ba in this embodiment. The lines 10, 12, 13, 15 and 16, and three-way solenoid valves 11 and 14 are similar in construction to those shown in FIG. 1.
The function of the balancing valve element 18 will be described with referring to FIGS. 2, 3(a) and 3(b).
Before the compressor 1 is started, the valve element 2B is retained in the passage 2Ac. Accordingly, when the compressor is started, the suction valve means 2 is in a full closed position. Thus, a negative pressure acts on an end surface of the valve element 2B and a load Pv is applied thereto as indicated in FIG. 3(a).
In the first embodiment, as shown in FIG. 3(a), a force corresponding to a following load difference P between the loads P c and P v applied to the piston 9E and the valve element 2B respectively is applied to the valve element 2B to open the suction valve means 2 when a connection state of a starter circuit 21 shown in FIG. 4 is converted from a Y-connection (Star-connection) to Δ-connection (Delta-connection) so that the outlet port 2Ab communicates with the opening 9Ab through the lines 16 and 13.
P=P.sub.c -P.sub.v =(π/4)×P.sub.1 ×(D.sub.2.sup.2 -D.sub.1.sup.2)
where
P: force for opening the suction valve means;
P 1 : negative pressure in the outlet port 2Ab;
D 1 : diameter of the valve element 2B;
D 2 : diameter of the piston 9E; and D 2 >D 1 .
The force acting on the valve element in the second embodiment of the invention will be explained with reference to FIG. 3(b).
Assuming that the diameter of the valve element 2B is equal to the diameter of the balancing valve element 18, the negative pressure applied to the valve element 2B is cancelled by the pressure applied to the balancing valve element 18.
Thus, the force P acting on the valve element 2B to open the suction valve means 2 increases in intensity as follows.
P=(π/4)×P.sub.1 ×D.sub.2.sup.2
where
P: force for opening the suction valve means;
P 1 : negative pressure in the outlet port 2Ab; and
D 2 : diameter of the piston 9E.
The increasement in the force acting on the valve element 2B makes the valve body 2B readily move rightwardly without the orifice 7 shown in FIG. 1, so that the suction valve means 2 is opened and the compressor 1 is switched from in the unload condition to in the load condition.
The operation for starting the compressor in the unload condition and then switching from the unload condition to the load condition will be explained as follows.
When the compressor 1 is started, the valve element 2B of the suction valve means 2 is retained in the passage 2Ac to close the suction valve means 2. Thus, the compressor 1 is started in the unload condition. At this time, the balancing valve 18 is inserted into the balancing recess 19. Since there is a small radial gap between the valve element 2B and the passage 2Ac, a small amount of air flowing through the gap into the compressor 1 is compressed therein and forwarded to the discharge line 1B.
In such unload starting, the pressure applied to the end surface of the valve element 2B facing the outlet port 2Ab is perfectly balanced to the pressure applied to the end surface of the balancing valve 18 facing the outlet port 2Ab.
The three-way solenoid valves 11 and 14 are so switched by means of the unload timer 24 shown in FIG. 4 in order to change the unload condition into the load condition, that the air flows in the lines 12 and 10 to the opening 9Aa as indicated by the solid line as shown in FIGS. 1 and 2. Accordingly, the pressure at a low level, which is about 0.1 kg/cm 2 (gauge) is applied to the end surface of the piston 9E associated with the opening 9Aa.
At the same time, the outlet port 2Ab is communicated with the opening 9Ab by such switching operation of the solenoid valve 14 and the negative pressure is applied to the opening 9Ab. Furthermore, the pressure applied to the valve element 2B is balanced to the pressure applied to the balancing valve element 18, as noted hereinabove. Therefore, the negative pressure applied to the end surface of the piston 9E associated with the opening 9Ab acts as a load for smoothly moving the valve element 2B apart from the valve seat 2Ac, to thereby bring the suction valve means 2 to an open position.
Accordingly, the compressor 1 is operated in the load condition (full load condition) instead of the unload condition. The compressor 1 is controlled in its displacement in the manner described above with reference to FIG. 4 wherein the pressure in the discharge line section 1Ba is detected by the pressure switch 8 and the two three-way solenoid valves 11 and 14 are suitably switched in accordance with the value of the sensed pressure to control the valve element 2B.
According to another form of the invention illustrated in pertinent part in FIG. 5, the three-way solenoid valves 11 and 14 can be replaced with a combination of on-off (one-way) valves 11X 1 , 11X 2 , 14X 1 and 14X 2 for effecting the same operation of the rotary compressor as described above. The positions of the valves in the several operation modes of the compressor are illustrated in the chart below.
__________________________________________________________________________ VALVEOPERATION MODE 14 X1 14 X2 11 X1 11 X2__________________________________________________________________________START & UNLOAD OPERATION CLOSED OPENED CLOSED OPENEDLOAD OPERATION OPENED CLOSED OPENED CLOSED__________________________________________________________________________
The invention may not be limited to a rotary compressor, such as a single stage oil-free screw compressor. The invention may be applicable to any other compressor. | A rotary compressor unit includes a compressor, a suction valve which holds a suction line of the compressor closed before it is started and which opens the suction line of the compressor after the compressor is started by means of using the negative pressure in the suction line of the compressor, which acts on the suction valve, and a balancing valve which assists the suction valve to open the suction line smoothly and surely. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a sliding auxiliary device for an electronic device, and in particular relates to a sliding auxiliary device assembled with a movable or sliding body, capable of assisting the movable body in increasing the stableness and reducing shakiness when the fitting process is performed.
[0003] 2. Description of the Related Art
[0004] For a conventional sliding cover system equipped in electronic devices such as mobile phones, notebook computers, personal digital assistants, digital cameras, e-books, etc., the sliding cover system can be reciprocally moved or slid by an external force, and a sliding cover portion of the sliding cover system is simply moved for the purpose of opening or closing.
[0005] As to the operation and movement of these kinds of sliding cover modules or sets, it is usually required cooperative components such as a movable rack, a linking plate, several elastic members, and wires or particular guide rails designed for linking and traction to assist with their opening or closing process. For the movable body of the electronic device with a heavy weight or a large movement distance, it is not expected that the motion stability of the sliding cover set or mechanism is influenced by the possible shakiness or swing when the movable body of the electronic device is operated by an user (e.g., applying with a single side-pushing force).
[0006] Accordingly, some following topics of these kinds of sliding cover modules with respect to the actual operation movement shall be considered or overcome.
[0007] 1. To possibly reduce the shakiness or swing of the sliding cover set, the sliding cover set shall be first equipped with an auxiliary device to assist in enhancing the stableness of sliding cover.
[0008] 2. The structure of the auxiliary device shall be provided with a reliable design of mechanism to assist in enhancing the motion stability and strength of the described components of the movable rack, the linking plate, the elastic members and the wires designed for linking and traction, so that the motion stability and smoothness of the sliding cover set can be relatively increased. Particularly, the auxiliary device shall be able to incorporate with a movable body of an electronic product with heavy weight and large movement distance.
[0009] Typically speaking, these reference data described above are related to the applications and design of structure of the sliding cover module or the related components thereof. However, these reference data are failed to physically teach or disclose that how to improve the conventional skills on decreasing the shakiness or swing of the sliding cover set and increasing the motion stability when the sliding cover module is operated.
[0010] Thus, it is essential to redesign a sliding cover and the related components, use patterns and applications thereof to be unique from that of the conventional skills.
BRIEF SUMMARY OF THE INVENTION
[0011] Accordingly, the main purpose of the invention is to provide a sliding auxiliary device to solve the difficulties and improve operation smoothness of the conventional skills. The sliding auxiliary device comprises an assembly of a rotating wheel, a gate linked to the rotating wheel, and a toggle mechanism. The toggle mechanism, assembled to the rotating wheel to define a reference axial line, comprises a first arm pivoted to the rotating wheel, a second arm pivoted to the first arm, and an elastic member disposed between the first arm and the second arm. The rotating wheel substantially drives the first arm and the second arm of the toggle mechanism to relatively move to store energy in the elastic member, and the elastic member releases the stored energy to generate an acting force to assist the rotation of the rotating wheel after the first arm of the toggle mechanism crosses over the reference axial line, to obtain an improved operation smoothness better than the conventional skills. The first arm of the toggle mechanism is defined with a first end eccentrically pivoted to the rotating wheel and a second end, and the second arm of the toggle mechanism is defined with a first end and a second end connected to the second end of the first arm to attach the elastic member therewith. Further, the first end of the second arm of the toggle mechanism is fixed or pivoted to a carrier or an auxiliary plate. Thus, when the first end of the first arm carried by the rotation of the rotating wheel is move, the second end of the first arm and the second end of the second arm force the elastic member to store energy therein, and the elastic member releases the stored energy to generate an acting force to assist with the rotation of the rotating wheel after the first arm crosses over the reference axial line.
[0012] According to the sliding auxiliary device of the invention, the gate is a type of a plate, producing a linear displacement relative to the rotating wheel in rotation. That is to say, when the gate actuated by an external force produces the linear displacement to relatively rotate the rotating wheel, the elastic member becomes to store energy therein or release energy therefrom.
[0013] According to the sliding auxiliary device of the invention, the rotating wheel, the gate linked to the rotating wheel, and the toggle mechanism of the sliding auxiliary device can be applied to a sliding cover module (or a sliding cover set). The sliding cover module comprises a substrate provided with a sliding rail, a belt wheel disposed on the substrate, a follower wheel arranged on the substrate to respectively engage to the belt wheel and the rotating wheel and driven by the belt wheel, a sliding rack movably attached to the sliding rail of the substrate, and a wire wound between the belt wheel and the sliding rack. When the sliding rack driven by the sliding cover set is reciprocally moved, the sliding racks drives the wire to rotate the belt wheels, so that the two follower wheels driven by the belt wheels drive the rotating wheels to rotate, respectively. When the rotating wheels are rotated, the rotating wheels drive the toggle mechanisms to store energy in or release the stored energy from the elastic member. That is, the rotating wheels, the gate and the toggle mechanisms provide an acting force to assist in moving the sliding cover module. Further, the design of structure of the rotating wheel, the gate and the toggle mechanism is therefore more compact and stable.
[0014] A detailed description is given in the following embodiments with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
[0016] FIG. 1 is a schematic view of an assembly of a rotating wheel, a toggle mechanism and a gate according to an embodiment of the present invention, representing that these components can be arranged on a carrier illustrated by imaginary line;
[0017] FIG. 2 is an exploded schematic view of the structure of FIG. 1 ;
[0018] FIG. 3 is a plan schematic view of FIG. 1 , representing that the toggle mechanism is in an initial position;
[0019] FIG. 4 is a schematic view of a motion of the rotating wheel, the toggle mechanism and the gate according to the present invention, wherein the toggle mechanism illustrated by imaginary line is crossed over a reference axial line;
[0020] FIG. 5 is a schematic view of an assembly of rotating wheels, toggle mechanisms, a gate and a sliding cover module according to an embodiment of the present invention, representing that the sliding cover module illustrated by imaginary line is in an open position; and
[0021] FIG. 6 is a schematic view of an assembly of rotating wheels, toggle mechanisms, a gate and a sliding cover module according to a modification embodiment of the present invention, representing that the sliding cover module illustrated by imaginary line is in an open position.
DETAILED DESCRIPTION OF THE INVENTION
[0022] 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 shall not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
[0023] Referring to FIGS. 1 and 2 , a sliding auxiliary device of the invention comprises an assembly of a rotating wheel and a toggle mechanism, represented by reference numbers 10 and 20 , respectively. In the adopted embodiments, the rotating wheel 10 is the type of gear. The rotating wheel 10 can be fixed on a substrate 30 illustrated by imaginary line, to be a type of free rotation.
[0024] In FIGS. 1 and 2 , the toggle mechanism 20 comprises a first arm 21 pivotally assembled to the rotating wheel 10 , a second arm 22 pivoted to the first arm 21 , and an elastic member 23 disposed between the first and second arm 21 and 22 . Specifically, in the toggle mechanism 20 , the first arm 21 is defined with a first end 21 a eccentrically pivoted to the rotating wheel 10 and a second end 21 b , and the second arm 22 is defined with a first end 22 a and a second end 22 b connected to the second end 21 b of the first arm 21 to attach the elastic member 23 therewith. The first end 22 a of the second arm 22 of the toggle mechanism 20 , functionally served as a positioning end, is rotatably and movably pivoted to or fixed at a carrier (e.g., a substrate 30 or an auxiliary plate), so that the first end 22 a of the second arm 22 of the toggle mechanism 20 is at least rotatable and/or movable with respect to a fulcrum, i.e., a fixed or a pivoting site, formed on the carrier.
[0025] In a preferred embodiment, the sliding auxiliary device is defined with a reference axial line X as the toggle mechanism 20 is assembled to the rotating wheel 10 . The reference axial line X corresponds to a connection line formed between a center of the rotating wheel 10 and the positioning end 22 a of the second arm 22 or an extension line merging the connection line. Generally, the reference axial line X is arranged on the radial direction or position of the rotating wheel 10 .
[0026] In the adopted embodiment, the first end 21 a of the first arm 21 of the toggle mechanism 20 is provided with a first hole through which a first fastener 40 passes to pivot to the rotating wheel 10 , and the first end 22 a of the second arm 22 of the toggle mechanism 20 is provided with a second hole through which a second fastener 40 passes to pivot to the carrier 30 . The second end 22 b of the second arm 22 of the toggle mechanism 20 is provided with a round-head profile which is to be hooked by the second end 21 b of the first arm 21 of the toggle mechanism 20 provided with a hook profile.
[0027] In this embodiment, the elastic member 23 is a type of torsion spring as presented in figures. The elastic member 23 comprises a pivotal end 23 a attached to the second end 22 b of the second arm 22 and a fixation end 23 b attached to a position in the vicinity of the second end 21 b of the first arm 21 . In practice, the rotating wheel 10 drives the first arm 21 and the second arm 22 of the toggle mechanism 20 to relatively move, i.e., the second end 21 b of the first arm 21 and the second end 22 b of the second arm 22 of the toggle mechanism 20 force the elastic member 23 to store energy therein when the first arm 21 is moved by the rotation of the rotating wheel 10 , and the elastic member 23 releases the stored energy to generate an acting force to assist with the rotation of the rotating wheel 10 after the first arm 21 crosses over the reference axial line X. The detailed description will be described hereinafter.
[0028] In one preferred embodiment, the rotating wheel 10 is interacted with a gate 50 . Specifically, the gate 50 is a type of a plate (or a rack) having an edge portion provided with an insection 51 being a type of engaging to the rotating wheel 10 , so that the gate 50 producing a linear displacement relative to the rotating wheel 10 in rotation. That is to say, when the gate 50 actuated by an external force produces the linear displacement to relatively rotate the rotating wheel 10 , the elastic member 23 becomes to store energy therein or release the stored energy therefrom.
[0029] Referring to FIG. 3 , in one preferred embodiment, the torsion spring can be replaced by a tension spring or a compression spring, illustrated by imaginary line, disposed between the first and second arms 21 and 22 .
[0030] Referring to FIGS. 3 and 4 , the conditions of the rotating wheel 10 , the toggle mechanism 20 and the gate 50 are illustrated. In FIG. 3 , the position of the rotating wheel 10 , the toggle mechanism 20 and the gate 50 is defined as an initial position or a first position. In FIG. 4 , when the rotating wheel 10 driven by an external force is rotated (an arrow representing on the rotating wheel 10 ) in a counterclockwise direction, the gate 50 driven by the rotating wheel 10 is moved toward the top of this figure, and the first end 21 a of the first arm 21 carried by the rotating wheel 10 is actually moved along a circumference path of the rotating wheel 10 , to rotate and force the elastic member 23 to store energy therein, subjected to the rotation of both the second end 21 b of the first arm 21 and the second end 22 b of the second arm 22 . When the first end 21 a of the first arm 21 is moved to the reference axial line X, as illustrated by imaginary line in FIG. 4 , the first and second arms 21 and 22 of the toggle mechanism 20 are stretched or almost reached to a distance having a maximum size or a farthest distance, i.e., the position that the elastic member 23 could be stored with largest energy.
[0031] In FIG. 4 , after the first end 21 a of the first arm 21 crosses over the reference axial line X with relation to the rotation of the rotating wheel 10 , the first and second arms 21 and 22 of the toggle mechanism 20 is enforced to move toward a position defined as a second position illustrated by real line, functioned by the toggle mechanism 20 itself, and the elastic member 23 releases the stored energy to generate the acting force to assist with the rotation of the rotating wheel 10 through the first arm 21 .
[0032] In FIG. 4 , when the rotating wheel 10 is reversed in a clockwise direction to carry the first end 21 a of the first arm 21 to move along the described circumference path of the rotating wheel 10 , it is understood that the second end 21 b of the first arm 21 and the second end 22 b of the second arm 22 rotate and force the elastic member 23 to store energy therein; meanwhile, the gate 50 driven by the rotating wheel 10 is moved toward the bottom of this figure. After the first end 21 a of the first arm 21 reversely crosses over the reference axial line X with relation to the rotation of the rotating wheel 10 , the first and second arms 21 and 22 of the toggle mechanism 20 is enforced to move toward the first position of FIG. 3 , functioned by the toggle mechanism 20 itself, and the elastic member 23 releases the stored energy to generate the acting force to assist with the rotation of the rotating wheel 10 .
[0033] Referring to FIG. 5 , an assembly of the rotating wheel 10 , the toggle mechanism 20 , the gate 50 and a sliding cover module (or sliding cover set 60 ) is represented. The sliding auxiliary device is disposed on the sliding cover module 60 . In this embodiment, the two symmetrical rotating wheels 10 and 10 ′ and the two symmetrical toggle mechanisms 20 and 20 ′ are preferably adopted. The toggle mechanism 20 ′ similarly comprises a first arm 21 ′, a second arm 22 ′, and an elastic member 23 ′ disposed between the first and second arms 21 ′ and 22 ′. Specifically, in the toggle mechanism 20 ′, the second arm 22 ′ has a first end 22 a ′ eccentrically pivoted to the rotating wheel 10 ′ and a second end 22 b ′, the first arm 21 ′ has a first end 21 a ′ functionally served as a positioning end or point and a second end 21 b ′ connected to the second end 22 b ′ of the second arm 22 ′ to attach the elastic member 23 ′ therewith. A connection line formed between the positioning end (or the pivotal position of the first end 21 a ′ of the first arm 21 ′) and a center of the rotating wheel 10 ′ is also defined as a reference axial line X.
[0034] In detail, the sliding cover module 60 comprises a substrate 61 provided with two sliding rails 61 a , an auxiliary plate 62 attached to the substrate 61 , two belt wheels 63 disposed on the substrate 61 and each of which provided with a toothed portion 63 a , two follower wheels 64 arranged on the substrate 61 and each of which respectively engaged to the toothed portion 63 a of the belt wheel 63 and the rotating wheel 10 or the rotating wheel 10 ′ and driven by the belt wheel 63 , two sliding racks or movable racks 65 movably attached to the sliding rails 61 a of the substrate 61 , and a wire 66 wound between the belt wheels 63 and the sliding racks 65 . The substrate 61 is selected from the type of plates being integrally formed, capable of being arranged on a fixed body of an electronic device (not shown in FIGs.). The auxiliary plate 62 is provided with a grooved rail 62 a and an opening 62 b formed on the grooved rail 62 a . The sliding racks 65 are arranged on a movable body of an electronic device (e.g., a sliding cover, but not shown in FIGs.). The sliding cover module 60 further comprises two tension pulleys 67 disposed on the auxiliary plate 62 to adjust the tension of the wire 66 wound between the belt wheels 63 and the sliding racks 65 .
[0035] In FIG. 5 , the gate 50 , movably fitted in the grooved rail 62 a of the auxiliary plate 62 , has an edge portion provided with an insection 51 which is exposed outwardly from the opening 62 b formed on the grooved rail 62 a and to be a type of engaging to the rotating wheels 10 and 10 ′. In the preferred embodiment, the gate 50 can be pivoted on the movable body of the electronic device or the related components of the sliding cover module 60 (e.g., a flat cable or others). Further, the first end 22 a of the second arm 22 of the toggle mechanism 20 and the first end 21 a ′ of the first arm 21 ′ of the toggle mechanism 20 ′ are respectively pivoted on the auxiliary plate 62 , functionally served as the positioning ends or points.
[0036] In FIG. 5 , the position of the sliding cover module 60 , together with the rotating wheels 10 and 10 ′, the toggle mechanisms 20 and 20 ′ and the gate 50 , illustrated by real line, is an initial position defined as a first position or (sliding cover) closed position, and the position of the sliding cover module 60 illustrated by imaginary line is a final position defined as a second position or (sliding cover) open position.
[0037] When an user moves the sliding cover or the sliding cover module 60 from the closed position toward the open position to drive the sliding racks 65 , the sliding racks 65 drives the wire 66 to rotate the belt wheels 63 , so that the two follower wheels 64 driven by the belt wheels 63 drive the rotating wheels 10 and 10 ′ to rotate, respectively. In FIG. 5 , the belt wheels 63 , the follower wheels 64 and the rotating wheels 10 and 10 ′ are individually marked with an arrow thereon representing rotation direction thereof. When the rotating wheels 10 and 10 ′ are rotated, the rotating wheels 10 and 10 ′ drives the toggle mechanisms 20 and 20 ′ and the gate 50 to form the same movement conditions depicted in FIGS. 3 and 4 . After the first arm 21 of the toggle mechanism 20 and the second arm 22 ′ of the toggle mechanism 20 ′ cross over the reference axial lines X respectively, the acting forces which are generated by the toggle mechanisms 20 and 20 ′ and released from the elastic members 23 and 23 ′ assist the wire 66 in moving the sliding cover and help to move the sliding cover toward the open position, thereby offering the user with more labor-saving method to control the sliding cover compared to conventional skills.
[0038] In FIG. 5 , when the user reverse the sliding cover module 60 from the second position (or open position) illustrated by imaginary line toward the first position (or closed position) illustrated by real line to move the sliding racks 65 , the sliding racks 65 drives the wire 66 to rotate the belt wheels 63 , so that the two follower wheels 64 driven by the belt wheels 63 drive the rotating wheels 10 and 10 ′ to rotate, respectively. When the rotating wheels 10 and 10 ′ are rotated, the rotating wheels 10 and 10 ′ drives the toggle mechanisms 20 and 20 ′ and the gate 50 to form the same movement conditions depicted in FIGS. 3 and 4 . After the first arm 21 of the toggle mechanism 20 and the second arm 22 ′ of the toggle mechanism 20 ′ cross over the reference axial lines X respectively, the acting forces which are generated by the toggle mechanisms 20 and 20 ′ and released from the elastic members 23 and 23 ′ assist the wire 66 in moving the sliding cover and help to move the sliding cover toward the closed position, thereby offering the user with more labor-saving method to control the sliding cover compared to conventional skills.
[0039] That is, with the design of structure of the rotating wheels 10 and 10 ′ and the toggle mechanisms 20 and 20 ′, an acting force is provided to assist in moving the sliding cover module 60 , thereby offering the user with labor-saving method to open or close the sliding cover or the sliding cover module 60 .
[0040] Note that the closed position (illustrated by real line) and the open position (illustrated by imaginary line) defined in FIG. 5 can be exchanged and embodied, for example, a modification embodiment of FIG. 6 . In FIG. 6 , the position of the sliding cover module 60 , together with the rotating wheels 10 and 10 ′, the toggle mechanisms 20 and 20 ′ and the gate 50 , illustrated by real line, is an initial position defined as a first position or (sliding cover) closed position, and the position of the sliding cover module 60 illustrated by imaginary line is a final position defined as a second position or (sliding cover) open position, wherein the gate 50 is located on the top of this figure.
[0041] When an user moves the sliding cover or the sliding cover module 60 from the closed position toward the open position to drive the sliding racks 65 , the sliding racks 65 drives the wire 66 to rotate the belt wheels 63 , so that the two follower wheels 64 driven by the belt wheels 63 drive the rotating wheels 10 and 10 ′ to rotate, respectively. In FIG. 6 , the belt wheels 63 , the follower wheels 64 and the rotating wheels 10 and 10 ′ are individually marked with an arrow thereon representing rotation direction thereof, and each of these components has an opposite rotation direction with respect to FIG. 5 . When the rotating wheels 10 and 10 ′ are rotated, the rotating wheels 10 and 10 ′ drives the toggle mechanisms 20 and 20 ′ and the gate 50 to move, so that the gate 50 is moved from the top to the bottom in this figure. After the first arm 21 of the toggle mechanism 20 and the second arm 22 ′ of the toggle mechanism 20 ′ cross over the reference axial lines X respectively, the acting forces which are generated by the toggle mechanisms 20 and 20 ′ and released from the elastic members 23 and 23 ′ assist the wire 66 in moving the sliding cover and help to move the sliding cover toward the open position.
[0042] In FIG. 6 , when the user reverses the sliding cover module 60 from the second position (or open position) illustrated by imaginary line toward the first position (or closed position) illustrated by real line, the sliding racks 65 is moved to drive the wire 66 to rotate the belt wheels 63 , so that the two follower wheels 64 driven by the belt wheels 63 drive the rotating wheels 10 and 10 ′ to rotate, respectively. When the rotating wheels 10 and 10 ′ are rotated, the rotating wheels 10 and 10 ′ drives the toggle mechanisms 20 and 20 ′ and the gate 50 to reverse. After the first arm 21 of the toggle mechanism 20 and the second arm 22 ′ of the toggle mechanism 20 ′ cross over the reference axial lines X respectively, the acting forces which are generated by the toggle mechanisms 20 and 20 ′ and released from the elastic members 23 and 23 ′ assist the wire 66 in moving the sliding cover and help to move the sliding cover toward the closed position, thereby offering the user with more labor-saving method to control the sliding cover compared to conventional skills.
[0043] Typically speaking, with the co-operative movement of the sliding cover module 60 , the sliding auxiliary device of the invention provided the following considerations and advantages compared to conventional skills.
[0044] By cooperating the rotating wheels 10 and 10 ′, the first and second arm 21 and 22 of the toggle mechanisms 20 , the first and second arm 21 ′ and 22 ′ of the toggle mechanisms 20 ′, the elastic members 23 and 23 ′, and the structural configuration of the gate 50 with the substrate 61 and the grooved rail 62 a of the auxiliary plate 62 to provide a reliable design of structure, the motion stability and strength of the sliding cover module 60 can be auxiliarily increased, and the smooth movement of the sliding cover module 60 can be enhanced.
[0045] Further, with the installation of the rotating wheels 10 and 10 ′, the first and second arm 21 and 22 of the toggle mechanisms 20 , the first and second arm 21 ′ and 22 ′ of the toggle mechanisms 20 ′, the elastic members 23 and 23 ′, and the structural configuration of the gate 50 , for example, exact meshing transmission among the belt wheel 63 , the follower wheel 64 and the rotating wheels 10 and 10 ′, and the gate 50 , shakiness or swing can be minimized when the sliding cover module 60 is operated by the user, especially of applying with a single side-pushing force, compared to the conventional skills. That is, the rotating wheels 10 and 10 ′, the gate 50 and the toggle mechanisms 20 and 20 ′ provide an acting force to assist in moving the sliding cover module 60 and a more compact and stable fitting structure therebetween.
[0046] More specifically, due to the sliding auxiliary device providing an acting force to assist in moving the sliding cover module 60 , the sliding auxiliary device is particularly suitable for a movable body (or a sliding cover) of an electronic device with heavy weight and large size and movement distance.
[0047] The ranges of motion or working angle between the first and second positions of the toggle mechanisms 20 and 20 ′ (e.g., of the first and second arm 21 and 22 and of the first and second arm 21 ′ and 22 ′) are related to the lengths of the first and second arm 21 and 22 and the lengths of the first and second arm 21 ′ and 22 ′. That is, if the lengths of the first and second arm 21 and 22 of the toggle mechanism 20 and the lengths of the first and second arm 21 ′ and 22 ′ of the toggle mechanism 20 ′ are changed (i.e., increased or decreased), the ranges of motion or working angle between the first and second arm 21 and 22 of the toggle mechanism 20 and between the first and second arm 21 ′ and 22 ′ of the toggle mechanism 20 ′ are relatively changed.
[0048] To sum up, the invention provides an effective sliding auxiliary device with a particular space configuration much different from that in the conventional skills, and therefore the advantages and improvements of the invention certainly surpass the conventional skills.
[0049] 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. | A sliding auxiliary device includes an assembly of a rotating wheel, a gate linked to the rotating wheel, and a toggle mechanism. The toggle mechanism includes a first arm pivoted to the rotating wheel, a second arm pivoted to the first arm, and an elastic member disposed between the first arm and the second arm. The rotating wheel substantially drives the first arm and the second arm of the toggle mechanism to relatively move to store energy in the elastic member, and the elastic member releases the stored energy to generate an acting force to assist the rotation of the rotating wheel after the first arm of the toggle mechanism crosses over a reference axial line, to obtain an improved operation smoothness better than the conventional skills. | 5 |
This application is a divisional of U.S. patent application Ser. No. 11/359,158 filed Feb. 21, 2006, now U.S. Pat. No. 7,254,704 which is a divisional of U.S. patent application Ser. No. 10/302,082 filed Nov. 22, 2002 (now U.S. Pat. No. 7,051,197), both of which are incorporated herein by reference.
TECHNICAL FIELD OF THE INVENTION
The technical field of this invention is emulation hardware particularly for highly integrated digital signal processing systems.
BACKGROUND OF THE INVENTION
Advanced wafer lithography and surface-mount packaging technology are integrating increasingly complex functions at both the silicon and printed circuit board level of electronic design. Diminished physical access to circuits for test and emulation is an unfortunate consequence of denser designs and shrinking interconnect pitch. Designed-in testability is needed so the finished product is both controllable and observable during test and debug. Any manufacturing defect is preferably detectable during final test before a product is shipped. This basic necessity is difficult to achieve for complex designs without taking testability into account in the logic design phase so automatic test equipment can test the product.
In addition to testing for functionality and for manufacturing defects, application software development requires a similar level of simulation, observability and controllability in the system or sub-system design phase. The emulation phase of design should ensure that a system of one or more ICs (integrated circuits) functions correctly in the end equipment or application when linked with the system software. With the increasing use of ICs in the automotive industry, telecommunications, defense systems, and life support systems, thorough testing and extensive real-time debug becomes a critical need.
Functional testing, where the designer generates test vectors to ensure conformance to specification, still remains a widely used test methodology. For very large systems this method proves inadequate in providing a high level of detectable fault coverage. Automatically generated test patterns are desirable for full testability, and controllability and observability. These are key goals that span the full hierarchy of test from the system level to the transistor level.
Another problem in large designs is the long time and substantial expense involved in design for test. It would be desirable to have testability circuitry, system and methods that are consistent with a concept of design-for-reusability. In this way, subsequent devices and systems can have a low marginal design cost for testability, simulation and emulation by reusing the testability, simulation and emulation circuitry, systems and methods that are implemented in an initial device. Without a proactive testability, simulation and emulation plan, a large amount of subsequent design time would be expended on test pattern creation and upgrading.
Even if a significant investment were made to design a module to be reusable and to fully create and grade its test patterns, subsequent use of a module may bury it in application specific logic. This would make its access difficult or impossible. Consequently, it is desirable to avoid this pitfall.
The advances of IC design are accompanied by decreased internal visibility and control, reduced fault coverage and reduced ability to toggle states, more test development and verification problems, increased complexity of design simulation and continually increasing cost of CAD (computer aided design) tools. In the board design the side effects include decreased register visibility and control, complicated debug and simulation in design verification, loss of conventional emulation due to loss of physical access by packaging many circuits in one package, increased routing complexity on the board, increased costs of design tools, mixed-mode packaging, and design for produceability. In application development, some side effects are decreased visibility of states, high speed emulation difficulties, scaled time simulation, increased debugging complexity, and increased costs of emulators. Production side effects involve decreased visibility and control, complications in test vectors and models, increased test complexity, mixed-mode packaging, continually increasing costs of automatic test equipment and tighter tolerances.
Emulation technology utilizing scan based emulation and multiprocessing debug was introduced more than 10 years ago. In 1988, the change from conventional in circuit emulation to scan based emulation was motivated by design cycle time pressures and newly available space for on-chip emulation. Design cycle time pressure was created by three factors. Higher integration levels, such as increased use of on-chip memory, demand more design time. Increasing clock rates mean that emulation support logic causes increased electrical intrusiveness. More sophisticated packaging causes emulator connectivity issues. Today these same factors, with new twists, are challenging the ability of a scan based emulator to deliver the system debug facilities needed by today's complex, higher clock rate, highly integrated designs. The resulting systems are smaller, faster, and cheaper. They have higher performance and footprints that are increasingly dense. Each of these positive system trends adversely affects the observation of system activity, the key enabler for rapid system development. The effect is called “vanishing visibility.”
FIG. 1 illustrates the trend in visibility and control over time and greater system integration. Application developers prefer the optimum visibility level illustrated in FIG. 1 . This optimum visibility level provides visibility and control of all relevant system activity. The steady progression of integration levels and increases in clock rates steadily decrease the actual visibility and control available over time. These forces create a visibility and control gap, the difference between the optimum visibility and control level and the actual level available. Over time, this gap will widen. Application development tool vendors are striving to minimize the gap growth rate. Development tools software and associated hardware components must do more with less resources and in different ways. Tackling this ease of use challenge is amplified by these forces.
With today's highly integrated System-On-a-Chip (SOC) technology, the visibility and control gap has widened dramatically over time. Traditional debug options such as logic analyzers and partitioned prototype systems are unable to keep pace with the integration levels and ever increasing clock rates of today's systems. As integration levels increase, system buses connecting numerous subsystem components move on chip, denying traditional logic analyzers access to these buses. With limited or no significant bus visibility, tools like logic analyzers cannot be used to view system activity or provide the trigger mechanisms needed to control the system under development. A loss of control accompanies this loss in visibility, as it is difficult to control things that are not accessible.
To combat this trend, system designers have worked to keep these buses exposed. Thus the system components were built in a way that enabled the construction of prototyping systems with exposed buses. This approach is also under siege from the ever-increasing march of system clock rates. As the central processing unit (CPU) clock rates increase, chip to chip interface speeds are not keeping pace. Developers find that a partitioned system's performance does not keep pace with its integrated counterpart, due to interface wait states added to compensate for lagging chip to chip communication rates. At some point, this performance degradation reaches intolerable levels and the partitioned prototype system is no longer a viable debug option. In the current era production devices must serve as the platform for application development.
Increasing CPU clock rates are also limiting availability of other simple visibility mechanisms. Since the CPU clock rates can exceed the maximum I/O state rates, visibility ports exporting information in native form can no longer keep up with the CPU. On-chip subsystems are also operated at clock rates that are slower than the CPU clock rate. This approach may be used to simplify system design and reduce power consumption. These developments mean simple visibility ports can no longer be counted on to deliver a clear view of CPU activity. As visibility and control diminish, the development tools used to develop the application become less productive. The tools also appear harder to use due to the increasing tool complexity required to maintain visibility and control. The visibility, control, and ease of use issues created by systems-on-a-chip tend to lengthen product development cycles.
Even as the integration trends present developers with a tough debug environment, they also present hope that new approaches to debug problems will emerge. The increased densities and clock rates that create development cycle time pressures also create opportunities to solve them. On-chip, debug facilities are more affordable than ever before. As high speed, high performance chips are increasingly dominated by very large memory structures, the system cost associated with the random logic accompanying the CPU and memory subsystems is dropping as a percentage of total system cost. The incremental cost of several thousand gates is at an all time low. Circuits of this size may in some cases be tucked into a corner of today's chip designs. The incremental cost per pin in today's high density packages has also dropped. This makes it easy to allocate more pins for debug. The combination of affordable gates and pins enables the deployment of new, on-chip emulation facilities needed to address the challenges created by systems-on-a-chip.
When production devices also serve as the application debug platform, they must provide sufficient debug capabilities to support time to market objectives. Since the debugging requirements vary with different applications, it is highly desirable to be able to adjust the on-chip debug facilities to balance time to market and cost needs. Since these on-chip capabilities affect the chip's recurring cost, the scalability of any solution is of primary importance. “Pay only for what you need” should be the guiding principle for on-chip tools deployment. In this new paradigm, the system architect may also specify the on-chip debug facilities along with the remainder of functionality, balancing chip cost constraints and the debug needs of the product development team.
FIG. 2 illustrates a prior art emulator system 100 including four emulator components. These four components are: a debugger application program 110 ; a host computer 120 ; an emulation controller 130 ; and on-chip debug facilities 140 . FIG. 2 illustrates the connections of these components. Host computer 120 is connected to an emulation controller 130 external to host 120 . Emulation controller 130 is also connected to target system 140 . The user preferably controls the target application on target system 140 through debugger application program 110 .
Host computer 120 is generally a personal computer. Host computer 120 provides access the debug capabilities through emulator controller 130 . Debugger application program 110 presents the debug capabilities in a user-friendly form via host computer 120 . The debug resources are allocated by debug application program 110 on an as needed basis, relieving the user of this burden. Source level debug utilizes the debug resources, hiding their complexity from the user. Debugger application program 110 together with the on-chip trace and triggering facilities provide a means to select, record, and display chip activity of interest. Trace displays are automatically correlated to the source code that generated the trace log. The emulator provides both the debug control and trace recording function.
The debug facilities are preferably programmed using standard emulator debug accesses through a JTAG or similar serial debug interface. Since pins are at a premium, the preferred embodiment of the invention provides for the sharing of the debug pin pool by trace, trigger, and other debug functions with a small increment in silicon cost. Fixed pin formats may also be supported. When the pin sharing option is deployed, the debug pin utilization is determined at the beginning of each debug session before target system 140 is directed to run the application program. This maximizes the trace export bandwidth. Trace bandwidth is maximized by allocating the maximum number of pins to trace.
The debug capability and building blocks within a system may vary. Debugger application program 100 therefore establishes the configuration at runtime. This approach requires the hardware blocks to meet a set of constraints dealing with configuration and register organization. Other components provide a hardware search capability designed to locate the blocks and other peripherals in the system memory map. Debugger application program 110 uses a search facility to locate the resources. The address where the modules are located and a type ID uniquely identifies each block found. Once the IDs are found, a design database may be used to ascertain the exact configuration and all system inputs and outputs.
Host computer 120 generally includes at least 64 Mbytes of memory and is capable of running Windows 95, SR-2, Windows NT, or later versions of Windows. Host computer 120 must support one of the communications interfaces required by the emulator. These may include: Ethernet 10 T and 100 T, TCP/IP protocol; Universal Serial Bus (USB); Firewire IEEE 1394; and parallel port such as SPP, EPP and ECP.
Host computer 120 plays a major role in determining the real-time data exchange bandwidth. First, the host to emulator communication plays a major role in defining the maximum sustained real-time data exchange bandwidth because emulator controller 130 must empty its receive real-time data exchange buffers as fast as they are filled. Secondly, host computer 120 originating or receiving the real-time data exchange data must have sufficient processing capacity or disc bandwidth to sustain the preparation and transmission or processing and storing of the received real-time data exchange data. A state of the art personal computer with a Firewire communication channel (IEEE 1394) is preferred to obtain the highest real-time data exchange bandwidth. This bandwidth can be as much as ten times greater performance than other communication options.
Emulation controller 130 provides a bridge between host computer 120 and target system 140 . Emulation controller 130 handles all debug information passed between debugger application program 110 running on host computer 120 and a target application executing on target system 140 . A presently preferred minimum emulator configuration supports all of the following capabilities: real-time emulation; real-time data exchange; trace; and advanced analysis.
Emulation controller 130 preferably accesses real-time emulation capabilities such as execution control, memory, and register access via a 3, 4, or 5 bit scan based interface. Real-time data exchange capabilities can be accessed by scan or by using three higher bandwidth real-time data exchange formats that use direct target to emulator connections other than scan. The input and output triggers allow other system components to signal the chip with debug events and vice-versa. Bit I/O allows the emulator to stimulate or monitor system inputs and outputs. Bit I/O can be used to support factory test and other low bandwidth, non-time-critical emulator/target operations. Extended operating modes are used to specify device test and emulation operating modes. Emulator controller 130 is partitioned into communication and emulation sections. The communication section supports host communication links while the emulation section interfaces to the target, managing target debug functions and the device debug port. Emulation controller 130 communicates with host computer 120 using one of industry standard communication links outlined earlier herein. The host to emulator connection is established with off the shelf cabling technology. Host to emulator separation is governed by the standards applied to the interface used.
Emulation controller 130 communicates with the target system 140 through a target cable or cables. Debug, trace, triggers, and real-time data exchange capabilities share the target cable, and in some cases, the same device pins. More than one target cable may be required when the target system 140 deploys a trace width that cannot be accommodated in a single cable. All trace, real-time data exchange, and debug communication occurs over this link. Emulator controller 130 preferably allows for a target to emulator separation of at least two feet. This emulation technology is capable of test clock rates up to 50 MHZ and trace clock rates from 200 to 300 MHZ, or higher. Even though the emulator design uses techniques that should relax target system 140 constraints, signaling between emulator controller 130 and target system 140 at these rates requires design diligence. This emulation technology may impose restrictions on the placement of chip debug pins, board layout, and requires precise pin timings. On-chip pin macros are provided to assist in meeting timing constraints.
The on-chip debug facilities offer the developer a rich set of development capability in a two tiered, scalable approach. The first tier delivers functionality utilizing the real-time emulation capability built into a CPU's mega-modules. This real-time emulation capability has fixed functionality and is permanently part of the CPU while the high performance real-time data exchange, advanced analysis, and trace functions are added outside of the core in most cases. The capabilities are individually selected for addition to a chip. The addition of emulation peripherals to the system design creates the second tier functionality. A cost-effective library of emulation peripherals contains the building blocks to create systems and permits the construction of advanced analysis, high performance real-time data exchange, and trace capabilities. In the preferred embodiment five standard debug configurations are offered, although custom configurations are also supported. The specific configurations are covered later herein.
SUMMARY OF THE INVENTION
A user may wish to diagnose the reason for resetting a data processor. Since the trace in the emulation is not reset upon functional reset, the user can have full visibility in the processor using the trace capability. This invention proposes real time tracing of data processor activity. The trace data enables program debug and analysis. This invention enables full visibility of data processor activity via trace through functional reset. The user can then view the trace data to diagnose the instruction address, data or data address that caused the functional reset.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects of this invention are illustrated in the drawings, in which:
FIG. 1 illustrates the visibility and control of typical integrated circuits as a function of time due to increasing system integration;
FIG. 2 illustrates an emulation system to which this invention is applicable (prior art);
FIG. 3 illustrates in block diagram form a typical integrated circuit employing configurable emulation capability (prior art);
FIG. 4 illustrates in block diagram form a detail of the trace collection hardware according to this invention;
FIG. 5 illustrates in block diagram form the pipeline flattener of this invention;
FIG. 6 illustrates in block diagram form one embodiment of the sliding alignment correction circuit of this invention; and
FIG. 7 illustrates in block diagram form an alternative embodiment of the sliding alignment correction circuit of this invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Even though the processor gets reset on a functional reset, the emulation hardware can give the user full diagnostic capability for the reason of the reset. The user can trace the timing stream to get an idea of when and how long the reset lasted. The user can use the program counter and data streams to diagnose the addresses/data values that could have lead to the reset.
FIG. 3 illustrates an example of a prior art one on-chip debug architecture embodying target system 140 . The architecture uses several module classes to create the debug function. One of these classes is event detectors including bus event detectors 210 , auxiliary event detectors 211 and counters/state machines 213 . A second class of modules is trigger generators including trigger builders 220 . A third class of modules is data acquisition including trace collection 230 and formatting. A fourth class of modules is data export including trace export 240 , and real-time data exchange export 241 . Trace export 240 is controlled by clock signals from local oscillator 245 . Local oscillator 245 will be described in detail below. A final class of modules is scan adaptor 250 , which interfaces scan input/output to CPU core 201 . Final data formatting and pin selection occurs in pin manager and pin micros 260 .
The size of the debug function and its associated capabilities for any particular embodiment of a system-on-chip may be adjusted by either deleting complete functions or limiting the number of event detectors and trigger builders deployed. Additionally, the trace function can be incrementally increased from program counter trace only to program counter and data trace along with ASIC and CPU generated data. The real-time data exchange function may also be optionally deployed. The ability to customize on-chip tools changes the application development paradigm. Historically, all chip designs with a given CPU core were limited to a fixed set of debug capability. Now, an optimized debug capability is available for each chip design. This paradigm change gives system architects the tools needed to manage product development risk at an affordable cost. Note that the same CPU core may be used with differing peripherals with differing pin outs to embody differing system-on-chip products. These differing embodiments may require differing debug and emulation resources. The modularity of this invention permits each such embodiment to include only the necessary debug and emulation resources for the particular system-on-chip application.
The real-time emulation debug infrastructure component is used to tackle basic debug and instrumentation operations related to application development. It contains all execution control and register visibility capabilities and a minimal set of real-time data exchange and analysis such as breakpoint and watchpoint capabilities. These debug operations use on-chip hardware facilities to control the execution of the application and gain access to registers and memory. Some of the debug operations which may be supported by real-time emulation are: setting a software breakpoint and observing the machine state at that point; single step code advance to observe exact instruction by instruction decision making; detecting a spurious write to a known memory location; and viewing and changing memory and peripheral registers.
Real-time emulation facilities are incorporated into a CPU mega-module and are woven into the fabric of CPU core 201 . This assures designs using CPU core 201 have sufficient debug facilities to support debugger application program 110 baseline debug, instrumentation, and data transfer capabilities. Each CPU core 201 incorporates a baseline set of emulation capabilities. These capabilities include but are not limited to: execution control such as run, single instruction step, halt and free run; displaying and modifying registers and memory; breakpoints including software and minimal hardware program breakpoints; and watchpoints including minimal hardware data breakpoints.
FIG. 4 illustrates a detail of trace collection 230 . Trace collection 230 hardware gets new trace data from the CPU core 201 every cycle. This trace comes form different pipeline stages of CPU core 201 . Pipeline flattener 401 combines all data from different clock cycles within the instruction pipeline that correspond to the same instruction. The data for each instruction is complete at the output of pipeline flattener 401 . Alignment logic 402 aligns the data coming from other parts of the emulation logic with the output of pipeline flattener 401 . This data then goes to trace logic 403 .
FIG. 5 illustrates the pipeline flattener 401 of this invention. Pipeline flattener 401 achieves alignment of program counter (pc), pipeline-flow control information (pctl), memory access control (mem_acc_ctl), memory access address (mem_addr), memory access write data (wr_data) and memory access read data (rd_data).
Alignment is implemented in 2 steps. First, the data collected in early stages of the pipeline is aligned in a per case bases in order to account for the differences in the data collection behavior. This presents a simpler group of data to the second processing step. Heterogeneous stage aligner 510 performs this initial alignment step. Second, the data collected in the first step presents a single type of behavior. The 3-stage delay pipeline 530 aligns this data from the first stage as a group to the last arriving memory access read data (rd_data).
The point of collection of the last arriving memory access read data (rd_data) is the target point of alignment. In this example this point of collection is stage 5 of the pipeline (e 5 ). As a first step towards the final alignment goal, the early arriving data is processed in various ways and aligned via heterogeneous stage aligner 510 to the second stage of the pipeline (e 2 ). In order to be considered fully aligned to e 2 , the data should not be updated at the beginning of the clock cycle if the pipeline did not advance in the previous cycle. This is indicated by cpu_stall=1 in previous cycle. For the example illustrated in FIG. 5 there are 5 sources of early arriving data program counter (pc), pipeline-flow control information (pctl), memory access control (mem_acc_ctl), memory access address (mem_addr) and memory access write data (wr_data). These represent 3 independent data retention policies and require 3 different mechanisms in order to be aligned to pipeline state e 2 as a group.
The pipeline-flow control information (pctl) data group is collected in pipeline stage el. This data has a data retention policy similar to the policy of any stage in the architectural pipeline. Thus all that is required to align pipeline-flow control information (pctl) to pipeline stage e 2 is the single stage pipeline delay element 511 . Pipeline delay element 511 is implemented by a single register stage that updates when the pipeline advances (cpu_stall=0).
A second set of early collected data is the program counter (pc). The program counter is generated in pipeline stage e 0 . The program counter is delayed 1 clock cycle via a single register stage (not shown) and then presented at the input of heterogeneous stage aligner 510 as the signal pc_e 0 +1 clock delay. Program counter (pc) data is aligned to pipeline stage e 2 via a single register stage in pipeline delay element 512 . Pipeline delay element 512 updates only when the pipeline advances (cpu_stall=0) and only if the current instruction in pipeline state e 1 is a new instruction (inst_exe=1). OR gate 513 advances receives the cpu_stall signal and the inst_exe signal and insures pipeline delay element 512 advances only under these conditions. Enforcing these 2 conditions ensures that the aligned program counter (pc) value in pipeline stage e 2 during multicycle instructions remains the same during all the cycles it takes to execute the instruction. This retention is in spite of the fact that the program counter (pc) retention policy will overwrite the program counter (pc) value presented after the first clock cycle of the instruction in pipeline stage e 1 .
The three remaining sets of early collected data are related to memory accesses. These are memory access control (mem_acc_ctl), memory access address (mem_addr) and memory access write data (wr_data). For the particular implementation illustrated in FIG. 5 , the three sources of data have a similar data retention policy and are collected in the same pipeline stages. Thus the same mechanism is used in order to align them to pipeline state e 2 . These 3 pieces of data are architecturally generated in pipeline stage e 2 . However, due to some special needs of this particular implementation there are a few exceptional cases where the memory access data is collected in pipeline stages e 1 and e 0 rather than pipeline stage e 2 .
Memory access elastic buffer 520 copes with these alternatives. Received memory access control data (mem_acc_ctl) supplies the input to two stage pipeline delay element 521 , the input to multiplexer 522 and an input to elastic buffer control 523 . The memory access address (mem_addr) and memory access write data (wr_data) supply the input to pipeline delay element 521 and multiplexer 522 . It should be understood that the memory access control data (mem_acc_ctl), the memory access address (mem_addr) and memory access write data (wr_data) are handled in parallel in pipeline delay element 521 and multiplexer 522 .
The memory access control data (mem_acc_ctl) indicates the pipeline stage of collection of the memory access signals. Elastic buffer control 523 uses this indication to control pipeline delay element 521 and multiplexer 522 . If the memory access data was collected during pipeline stage e 2 , then elastic buffer control 523 sends a select signal to multiplexer 522 to select the directly received memory access signals. If the memory access data was collected during pipeline stage e 1 , then elastic buffer control 523 sends a select signal to multiplexer 522 to select memory access signals from pipeline delay element 521 . Elastic buffer control 523 also controls pipeline delay element 521 to insert one pipeline stage delay. If the memory access data was collected during pipeline stage e 0 , then elastic buffer control 523 sends a select signal to multiplexer 522 to select memory access signals from pipeline delay element 521 . Elastic buffer control 523 also controls pipeline delay element 521 to insert two pipeline stage delays. This behavior is summarized in Table 1.
TABLE 1
Data
Multiplexer
Pipeline delay
collected
522 select
element 521
e0
delayed data
2 stage delay
e1
delayed data
1 stage delay
e2
direct data
—
The 3-stage delay pipeline 530 takes the homogeneously behaved data at its input already aligned to the second pipeline stage e 2 . Three-stage delay pipeline 530 includes pipeline delay element 531 for the memory access data, pipeline delay element 532 for the program counter data and pipeline delay element 533 for the pipeline-flow control information. Three-stage delay pipeline 530 outputs this data at pipeline stage e 5 . This is the same stage as the arrival of the read data (rd_data). Three-stage delay pipeline 530 sends every bit of input data through 3 serially connected registers that update its content every clock cycles that the pipeline is not stalled (cpu_stall=0). The clock signal clkl is supplied to pipeline delay elements 511 and 512 and to every register of pipeline delay elements 521 , 531 , 532 and 533 . The cpu_stall signal stalls pipeline delay elements 511 , 512 , 531 , 532 and 533 when the central processing unit is stalled. Since the memory access data is not updated by heterogeneous stage aligner 510 during pipeline stall cycles, no data is lost during pipeline stalls. Pipeline flattener 401 effectively aligns the program counter (pc), pipeline-flow control information (pctl), memory access control (mem_acc_ctl), memory access address (mem_addr), memory access write data (wr_data) to the late received read data (rd_data) in pipeline stage e 5 .
FIG. 6 illustrates alignment circuit 402 in one embodiment of this invention. The data presented at the input of this circuit is aligned to the cycle and pipeline stage where the last set of data, the memory access read data (rd_data), becomes available. In this example the data processor has a five stage pipeline. Thus the write data (wr_data_e 5 ), memory access control data (mem_acc_ctl_e 5 ), memory address (mem_addr_e 5 ), program counter (pc_e 5 ) and pipeline-flow control information (pctl_e 5 ) has been aligned with the late arriving read data (rd_data) in pipeline stage e 5 .
In FIG. 6 although all the data presented at the input of the circuit is be aligned to pipeline stage e 5 , there is an issue with 1 clock cycle sliding of read data (rd_data) that could cause it not to be correctly captured if the pipeline stalls. The 1 clock cycle sliding of read data (rd_data) happens when the read data (rd_data) presented at the input boundary of the circuit as it updates one more cycle once the pipeline stalls. As part of this behavior the same source of read data (rd_data) will not be updated like the rest of the aligned data at the beginning of the second pipeline advance cycle after the stall. In other words the 1 cycle sliding of the read data (rd_data) could be described as a 1 cycle delay in response to the stall or advance taking place in the pipeline.
In order to prevent the potential lost of the read data, additional registering stage is inserted in the path of the data. This one pipeline stage delay is implemented via pipeline delay elements 601 , 602 , 603 , 604 and 605 . The pipeline delay element 605 provides storage to capture the read data (rd_data) and eliminates the loss of read data associated with the instruction in pipeline state e 5 being overwritten when the read data in pipeline stage e 4 slides into pipeline stage e 5 during the first cycle of a CPU stall window. Pipeline delay elements 601 , 602 , 603 and 604 do not hold data and have been added as delay elements to compensate for the delay of pipeline delay register 605 , which captures and holds the read data. In order to remove the 1 clock slide in the read data, the hold signal supplied to pipeline delay register 605 is a 1 clock delayed version of the pipeline stall signal (cpu_stall) provided by delay element 606 .
FIG. 6 illustrates two additional register stages in each data path: pipeline delay elements 611 and 621 in the write data path, pipeline delay elements 612 and 622 in the memory access control data and the memory address paths; pipeline delay elements 613 and 624 in the program counter path; pipeline delay elements 614 and 624 in the pipeline-flow control information path; and pipeline delay elements 615 and 625 in the read data path. These two additional stages add additional latency specific to this implementation of the preferred embodiment of the invention. The 3 additional register stages alignment circuit 602 do not represent additional pipeline stages, they only add clock latency to the implementation. The data at the output of alignment circuit 602 is the contents of pipeline stage e 5 in the pipeline delayed by 3 clock cycles.
The correction to the N-bit sliding on the memory data is done via an N-bit slide operation in the opposite direction to the slide of the data. The data bus is assumed to be 2 words wide in this embodiment. The sliding of data at the input is limited to a swapping between the upper and lower words of the bus. Shift correction circuit 630 receives the memory access control signal and detects the sliding condition. Shift correction circuit 630 controls multiplexers 631 , 632 , 633 , and 634 to enable or disable a swap of the most significant and least significant bits. In order to restore the architectural view of the data it is necessary to align the least significant bits of the write data and the read data to the least significant bits of the data bus. On a normal state of the multiplexer control signal from shift control circuit 630 multiplexer 631 selects the most significant bits from pipeline delay element 601 to output to the most significant bits of pipeline delay element 611 , multiplexer 632 selects the least significant bits from pipeline delay element 601 output to the least significant bits of pipeline delay element 611 , multiplexer 633 selects the most significant bits from pipeline delay element 605 to output to the most significant bits of pipeline delay element 615 , multiplexer 634 selects the least significant bits from pipeline delay element 605 output to the least significant bits of pipeline delay element 611 . In the opposite swap state multiplexer 631 selects the least significant bits from pipeline delay element 601 to output to the most significant bits of pipeline delay element 611 , multiplexer 632 selects the most significant bits from pipeline delay element 601 output to the least significant bits of pipeline delay element 611 , multiplexer 633 selects the least significant bits from pipeline delay element 605 to output to the most significant bits of pipeline delay element 615 , multiplexer 634 selects the most significant bits from pipeline delay element 605 output to the least significant bits of pipeline delay element 611 . This swaps the most significant bits with the least significant bits of both the write data and the read data.
FIG. 7 illustrates alignment circuit 700 in an alternative embodiment of this invention. In this alternative clock delay elements 601 , 602 , 603 and 604 are replaced with respective pipeline delays elements 701 , 702 , 703 and 704 . An additional pipeline delay has been added by holding the contents of pipeline delay elements 701 , 702 , 703 , and 704 by connecting their hold inputs to the cpu_stall signal. As a result the pipeline data aligned to pipeline stage e 5 presented as input of adjustment circuit 700 will require that the pipeline advances one more stage to pipeline stage e 6 , before it could be propagated via 2 stages of latency to the output.
Reset for the trace logic and CPU core 201 is qualified as shown in Table 2. Table 2 gives some background knowledge about interaction of reset, CPU core 201 and trace.
TABLE 2
Trace
Functional
Logic
Reset
Reset
Unit owned by
reset
reset
CPU
Trace
Not owned
Y
—
Y
Y
Not owned
—
Y
Y
Y
Application
Y
N
Y
Y
Application
N
Y
N
N
Debugger
Y
N
Y
N
Debugger
N
Y
N
Y
Pipeline flattener 401 and alignment logic 402 are reset when CPU core 201 resets. However trace logic 403 is only reset as shown in Table 2. As shown in Table 2, trace logic 403 can only trace through reset when the debugger/emulator owns the reset and there is a functional reset.
The reset request is initiated via emulation hardware. The reset information from CPU core 201 cannot be used for trace collection 230 . By the time such information is pipelined and sent to trace collection 230 , it misses the window in which the reset started. Therefore, the reset signal sent to trace collection 230 is a pipelined version of the reset sent to CPU core 201 .
The user sees the following sequence:
1. Normal information traced;
2. Start of reset information;
3. Timing cycles indicating no activity;
4. Active timing bits indicating the activity of boot load code;
5. Stalls indicating the loading of instruction memory;
6. Exception to address 0 , where the reset code resides.
The user can use this sequence to diagnose the probable location of reset, the duration for reset and any other information that might interest him. | A method of tracing a data processor upon reset of the data processor. A data processor reset signal resets the data processor, part of trace collection hardware and does not reset remaining parts of trace collection hardware. The data processor reset signal may be not owned, owned by an application program or owned by a debugger. The partial not reset of the trace collection hardware occurs only upon a data processor reset signal owned by the debugger. A trace logic reset signal resets both the data processor and the trace collection hardware when not owned. This trace logic reset signal resets the data processor only when owned by the debugger and resets the trace collection hardware when owned by an application program. | 6 |
BACKGROUND OF THE INVENTION
In sewing machines it is desirable in some sewing situations to be able to use more than one needle as in the case, for example, of multicolored embroidery stitching. When substituting two or more needles for a single needle in a zig-zag machine, it becomes necessary to limit the swing amplitude of the needles, or the bight stops, as the two or more needles would swing in a wider path than a single needle which could take the needles out of the area covered by the aperture in the needle plate resulting in a breaking of the needles during penetration of the fabric. It is known to limit the bight stops in mechanically controlled zig-zag machines when substituting multiple needles for single needles, such as for example shown in U.S. Pat. No. 3,296,987 granted Jan. 10, 1967. In such mechanically controlled machines the zig-zag motion is generally imparted to the needle bar by a cam mechanism which is connected to the needle bar mechanism through a cam follower and associated linkage. In order to adjust or limit the bight stops in such machines means are generally provided for altering the linkage between the cam mechanism and the needle bar mechanism.
In electronically controlled sewing machines of the type disclosed in co-pending U.S. patent application Ser. No. 431,649 .Iadd.(now patent #3,984,745) .Iaddend.filed on Jan. 8, 1974, cam mechanisms of the type mentioned above are completely eliminated and logic means are used to select and release stitch information stored in a memory means in timed relation with the operation of the sewing machine. Digital information from the memory means is converted to positional analog signals which control closed loop servo means including moving coil linear actuators directly controlling the position of conventional stitch forming instrumentalities such as the zig-zag mechanism for the needle bar. Therefore it will be seen that in machines of this type means other than those which have been provided heretofore must be used for limiting the bight stops. What is required in order to limit the bight stops in an electronically controlled machine is means for limiting the positional analog signals which control the closed loop servo means to thereby provide a signal to said servo means which is reduced in proportion to the reduction in swing amplitude or bight required for the situation wherein multiple needles or the like are used.
SUMMARY OF THE INVENTION
As briefly mentioned above, a machine of the type disclosed in this invention is controlled by electronic means including logic means which select and release stitch information from a stored memory in timed relation with the operation of the sewing machine and in accordance with a pattern selected by the operator. The signal from the memory is presented in digital form and is converted in a digital-to-analog converter and through suitable amplification is fed to a moving coil linear actuator which directly controls the position of the needle bar mechanism. A feedback circuit is also provided which senses the position of the linear actuator in accordance with time and location and modifies the input signal so that the actuator will accurately assume the position as called for by the original information released from the memory.
U.S. patent application Ser. No. 596,683 .Iadd.(now patent #4,016,821) .Iaddend.filed July 16, 1975 discloses a means for overriding the analog signal provided by the digital-to-analog converter for both feed and bight pattern information thereby providing a variable control of said signal to the linear actuator. Such a system is desirable for modifying the pattern information, as for example, to obtain an optimum button hole that would have a balanced appearance. However, it has been found that in situations where multiple needle use can be optionally selected on the machine, fixed bight stop limits should be provided so as to prevent any possibility of needle breakage or the like. In accordance with the present invention circuit means are provided which, when selectively operational, impose a fixed limit on the analog signal at the output of the digital-to-analog converter. Such fixed limit is imposed prior to input to the linear actuator and also prior to the operation of any override controls, as described above, so that there is no danger in the operator modifying the signal with the override control to cause the needles to swing a greater amplitude than is desired.
Accordingly, it is one object of the invention to provide a novel and improved bight stop mechanism for a sewing machine.
It is another object of the invention to provide a novel and improved bight stop mechanism for an electronically controlled sewing machine.
It is a further object of the invention to provide a novel and improved bight stop mechanism for limiting the swing amplitude of the needle bar in a zig-zag sewing machine when a multiple needle mode is selected.
Other objects and advantages of the invention will be best understood when reading the following description with the accompanying drawings as identified below.
DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of a sewing machine showing fragmented portions of the sewing instrumentalities and control mechanisms necessary to illustrate the physical elements of the invention;
FIG. 2 is a general schematic block diagram for the bight control system of the invention; and
FIG. 3 is a circuit diagram showing the bight control circuits of the invention.
DESCRIPTION OF THE INVENTION
Referring to the drawings there is illustrated in FIG. 1, a sewing machine, partially in phantom, including a frame 10 having a bed 12 and a bracket arm 14 supported in an overhanging relationship to the bed by a standard 16. The free end of the bracket arm 14 includes a head portion 18 in which is supported a needle bar gate 20 which in turn supports a needle bar 22 for reciprocating motion in an endwise direction in the usual manner as found in sewing machines. Endwise reciprocating motion is imparted to the needle bar 22 through suitable connection with an arm shaft 24 driven in the conventional manner as by an electric motor or the like (not shown). A single needle or a plurality of needles 26, as illustrated are supported in the lower extremity of the needle bar 22 and are disposed for cooperation beneath the bed 12 with suitable sewing instrumentalities such as a looper (not shown) or the like.
As is known in zig-zag sewing machines, the needle bar gate 22 is operatively associated with actuating mechanism for imparting lateral jogging motion to the needle bar 22, which, as illustrated in FIG. 1, includes a drive arm 28 pivotally connected to the needle bar gate as illustrated at 30. The drive arm 28 is operably connected to a reversible linear motor or actuator 32 for imparting a linear motion to the drive arm 28 and as a result jogging motion to the needle bar gate 20 through the pivot connection 30. Reference may be made to U.S. patent application Ser. No. 431,649 filed on Jan. 8, 1974 and assigned to the same assignee as the present invention for a more detailed description of the linear actuator. Disposed within the bed 12 and below the needle bar 22 for operation in association therewith is a needle plate 34 which includes an aperture 36 having a width sufficient to at least accommodate a single needle during maximum width zig-zag motion. Supported beneath the bed plate 12 is a feed mechanism for feeding the work across the surface of the bed plate and includes a feed dog 38 operably connected with suitable linkage generally indicated at 40 which in turn is connected to a second linear motor or actuator 42. As described in co-pending application Ser. No. 596,683 filed July 16, 1975 and assigned to the same assignee as the present invention, the feed mechanism is also electronically controlled so that electronic signals are fed to the linear actuator 42 to position the feed mechanism for the desired forward or reverse feed in accordance with a selected pattern. The feed mechanism itself forms no part of the present invention and for purposes of the present invention other suitable feed mechanisms may be incorporated herein.
Referring to FIG. 2, illustrated therein is a schematic block diagram for the bight control portion of the sewing machine. The feed control portion is not illustrated and is essentially the same as the bight control circuitry and reference to the bight control circuitry illustrated in FIG. 2 will be sufficient for purposes of understanding either of the aforementioned control circuits. For a more detailed description of the feed control circuit reference may be made to the aforementioned U.S. patent application Ser. No. 596,683. As previously mentioned, pattern information may be stored in a memory device which in the present invention is incorporated in a MOSFET Large Scale Integration (LSI) integrated circuit designated at 44 in FIG. 2. One method of extracting the information from the LSI 44 for presenting the same to the digital-to-analog converter for bight and feed control is disclosed in U.S. Pat. No. 3,855,956, assigned to the same assignee of the present invention. As disclosed therein digital information related to the positional coordinates for each stitch of a predetermined stitch pattern is stored in a static memory such as included in LSI 44. A pulse generator 46 (see also FIG. 1) is driven in timed relation with the sewing machine and produces a timing signal pulse between each successive stitch. The signal pulses are counted in a binary counter 48 to provide a timed series of progressively increasing binary numbers corresponding to the progressively increasing number of stitches in the pattern. The output of the counter is applied as the address to the memory to recover as output therefrom the digital information related to the positional coordinates for each stitch of the predetermined pattern. The memory output is applied to control driving devices operatively connected to impart a control range of movement to the needle and the feed of the sewing machine to produce a specific predetermined position coordinate for the needle penetration during each stitch formation.
As further illustrated in FIG. 2, the pulses from the pulse generator 46 are counted by binary counter 48 and presented at address input to the LSI 44. The LSI is illustrated in FIG. 1 as being mounted on a logic printed circuit board 50. The output of the LSI 44 is presented as output digital information related to the positional coordinates for each stitch in pulse width modulated form to digital-to-analog converter 52 for the bight. The LSI 44 may also include a latch whereby the bight information may be held for timed release to the bight servo system at a time appropriate to the operation of the needle jogging mechanism in the stitching operation. Proper timing for the release of the bight information may be determined by the pulse generator 46.
The pulse width modulated signal presented along line 54 to the digital-to-analog converter 52 is filtered, offset by rheostat 56 (FIG. 3) and scaled by a voltage divider 58 in the converter in order to accommodate a specific LSI 44 to those components between the LSI and the load to account for manufacturing variability. Analog signals from the digital-to-analog converter 52 have an output on line 60 to a bight signal control amplifier 62 which outputs on line 64 to the summing point 66 of a low level preamplifier 68 of a servo amplifier system. Further reference to the servo amplifier system may be found in the aforementioned U.S. patent application Ser. No. 431,649.
The output from the bight signal control amplifier 62 is also connected by way of line 70 to FET 72 of the enhancement type, having its gate connected by gate line 74 to the LSI 44. On suitable command the LSI 44 will apply a gate voltage through a latch circuit to FET 72 by way of gate line 74 thereby to place and retain FET 72 in the conductive or ON condition. A feedback signal then passes through line 70 and FET 72 to a wiper of a rheostat 78 supported on control block 76 (see FIGS. 1 and 3).
Thus, the gain of the bight signal control amplifier 62 may be controlled during pattern stitching or straight stitching through manual adjustment of the manual bight control rheostat 78. The manual bight control rheostat 78 which as seen in FIG. 1 is adjusted by a knob 80 and is mounted on power supply and override printed circuit board 82. Energization of the circuitry to LSI 44 for applying a gate voltage to FET 72 may be accomplished by a proximity switch associated with knob 80 and may be of the type described in co-pending U.S. patent application Ser. No. 596,685, filed on July 16, 1975, entitled "Digital Differential Compacitance Proximity Switch" which is assigned to the same assignee as the present invention. Rotation of knob 80 rotates wiper 84 of rheostat 78 for adjustment of the bight control signal. Further details of the override arrangement may be had by referring to the aforementioned co-pending application Ser. No. 596,683, filed July 16, 1975. As also mentioned in the co-pending application just referred to, override controls may also be provided for the feed signals and to the balance of the feed and may be represented in the present application by knobs 86 and 88 which respectively control balance and feed through suitable rheostats and circuitry similar to that described in relation to the bight control circuits above. For purposes of the present invention it need only be understood that override circuit means may be provided for modifying the bight control signal after its amplification by bight signal control amplifier 62.
As further illustrated in FIG. 3, the bight signal control amplifier 62 is indicated as an operational amplifier with rheostat 78 providing the feedback to the input. A MOSFET module 90, such as RCA type CD 4016A, comprises a plurality of dependent bilateral signal switches one of which is switch 72. The module may also be mounted on a printed circuit board 82 (see FIG. 1). As shown in the schematic of FIG. 3 a voltage signal from LSI 44 on line 74 will place FET 72 in an ON condition, inserting the wiper 84 of rheostat 78 in by-pass arrangement in the feedback circuit. Feedback resistance of the operational amplifier 62 may thereby be reduced to decrease the gain of the operational amplifier and reduce the analog signal to the summing point 66 of the low level preamplifier 68 of the servo amplifier system mounted on servo circuit board 92. Preamplifier 68 drives a power amplifier 94 which supplies direct current of reversible polarity to the electromechanical actuator 32, which in the broadest sense comprises a reversible motor, to position the actuator in accordance with the input analog voltage on line 64. A feedback position senser 96 mechanically connected to the reversible motor 32 provides a feedback position signal on line 98 indicative of the existing output position. The input analog voltage and the feedback signal are algebraically summed at the summing point 66 to supply an error signal on line 100. The feedback signal from the position sensor is also differentiated with respect to time in a differentiator 102 and the resulting rate signal is presented on line 104 to the summing point 106 of the power amplifier 94 to modify the positional signal at that point. The position sensor 96 may be any device that generates an analog voltage proportional to position and may be a simple linear potentiometer connected to a stable reference voltage and functioning as a voltage divider. The differentiator 102 is preferably an operational amplifier connected to produce an output signal equal to the time rate of change of the input voltage.
While the reversible motor 32 may be a conventional low-inertia rotary d.c. motor, it is preferable, for purposes of the present invention that it takes the form of a linear actuator in which a lightweight coil moves linearly in a constant flux field and is directly coupled to the load to be positioned. This simplifies the driving mechanical linkage and minimizes the load inertia of the system. A suitable power supply circuit (not shown) may be connected to the AC house mains via a transformer for supplying 12 volt 60 hertz to the power supply. The supply, reduced to 12 volts a.c. undergoes full wave rectification, and filtration to provide ± 15 VDC to the power amplifiers and also to provide, through voltage regulators of a suitable type, ± 7.5 VDC in the bight position potentiometer 96 as well as ± 7.5 VDC to the digital-to-analog offset voltage dividers in the digital-to-analog converter 52. Although not shown, the power supply also provides ± 7.5 VDC to LSI 44. As the power supply itself forms no part of the present invention, reference may be made to co-pending application Ser. No. 596,683 mentioned above for a more detailed description of the type power supply which may be used with the present invention. Also, reference may be made to the same co-pending application for a more detailed description of the construction and operation of the LSI itself.
When sewing ornamental patterns, such as in embroidery stitching or the like, wherein more than one color thread is desired, or in cases wherein parallel lines of ornamental stitches are desired, it is necessary to substitute a multiple needle holder for the single needle generally used with the machine. It will be readily apparent that when more than one needle is held in the needle bar, if the same swing amplitude or bight is used for zig-zag stitching as was in the case of a single needle, one or both of the needles in the case of using two such needles may not align itself with the needle plate aperture 36 during penetration of the fabric. Means must therefore be provided to insure that the swing amplitude or bight of the needles does not exceed the width of the needle plate aperture. In accordance with the present invention additional circuit means are provided for modifying the electronic pattern control signal for the bight so that when the machine is in a multiple needle mode the maximum bight will be automatically reduced in proportion to the number of needles carried by the needle bar.
Referring to FIGS. 1, 2 and 3, a switch 110 is carried by control panel 76 and has its contacts in parallel through lines 112 and 114 with the output line 60 of the digital-to-analog converter 52. .Iadd.Preferably, the circuit is arranged such that when the switch 110 is open, the bight will be reduced for multiple needle sewing, and when the switch 110 is closed, a wider bight will be available for single needle sewing. .Iaddend.It will be recalled, as discussed above, the digital-to-analog converter 52 puts out an analog signal which is converted from the digital information from the memory to provide a control signal for the bight in accordance with a selected pattern. In order to reduce the signal from the digital-to-analog converter 52, a fixed resistance in the form of a resistor 116 is placed in line 114 which resistor 116 has a resistance selected so that it will reduce the analog voltage from the digital-to-analog converter in an amount proportion to the number of needles, which in the case of switch 110 and its associated circuit in the preferred embodiment illustrated is selected for twin or two needle sewing. Thus, for example, the resistance of resistor 116 may be such to .[.reduce.]. .Iadd.influence .Iaddend.the output from the digital-to-analog converter by an amount of 50%. It will be further seen that the parallel circuit containing switch 110 and resistor 116 is inserted into the circuitry prior to the application of any override or feedback signals, as would appear on line 70 subsequent to amplification of the bight control signal through bight signal control amplifier 62. Therefore, .[.when the switch 110 is closed to insert the resistance 116 into the circuit.]. any modification of the signal thereafter as through the override controls or the feedback .[.would only.]. .Iadd.could not .Iaddend.have an effect on .[.a reduced.]. .Iadd.the maximum .Iaddend.value .Iadd.of the .Iaddend.control signal. By this means any modification of the bight control signal would not give rise to any concern that the swing amplitude of the needles would exceed the width of the needle plate aperture 36. It will also be understood, that instead of a single position switch 110 a multiple position switch may be provided wherein multiples of resistance may be inserted into the circuit in the same manner as the resistor 116 for situations wherein more than two needles will be used in the needle bar.
It will be seen from the above description that a novel and improved bight stop control mechanism is provided for a sewing machine for limiting the swing amplitude of a needle bar during zig-zag stitching when more than one needle is present in the needle bar. In particular, means are provided for modifying electronic bight control signals when the sewing machine is placed in a multiple needle mode to limit the swing amplitude of the needle bar so as to prevent any damage to the needles or the work or other elements of the sewing machine. While the invention has been described in its preferred embodiments, it will be obvious to one skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the appended claims. | The present disclosure relates to zig-zag sewing machines including means for controlling the bight stops in order to produce ornamental patterns. In particular, the disclosure relates to electronically controlled sewing machines having storage means for storing stitch information and wherein logic means are used to select and release stitch information in timed relation with the operation of the sewing machine. The disclosure of the invention has particular application in those sewing situations wherein it is desired to use more than one needle in a single needle holder of the needle bar which therefore necessitates a limitation on the magnitude of the jogging or swinging of the needle bar in order to accommodate the multiple needles in the aperture of the needle plate. In accordance with the disclosure of the present invention whenever more than one needle is used in the sewing machine the electronic control of the bight stops is automatically put into effect whenever such multiple needle mode is selected. | 3 |
This application is a divisional of application Ser. No. 08/991,439, filed on Dec. 16, 1997, which is a continuation of application Ser. No. 08/375,990, filed on Jan. 20, 1995, both now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an elastic blade for regulating the layer thickness of a toner, a method of manufacturing the same and a developing device using the elastic blade.
2. Related Background Art
Heretofore, in the developing device of an image forming apparatus such as an electrophotographic apparatus, the thickness of a toner layer on a developing sleep carrying a toner thereon has been regulated by an elastic blade and triboelectricity has been imparted to the toner by friction.
A blade made of rubber is used as such elastic blade.
However, this rubber blade, when used for a long period, has caused a variation with time (plasticity deformation) in its elastic material and has suffered from a problem in durability.
So, there has been proposed a developing device utilizing, as a blade for regulating the quantity of developer, a blade of two or more layers comprised of an elastic layer for regulating the amount of charge of a developer and a support layer for regulating pressure adhesively secured to the elastic layer.
However, the support layer of this blade of two-layer construction is thin and elongate and therefore gives rise to warp.
For this reason, this blade is affected by the warp of the support layer and it is difficult to obtain uniform contact pressure in the lengthwise direction of a developing sleeve and therefore, it would occur to mind to form a blade for regulating the quantity of developer which is high in flatness. If the flatness of the blade for regulating the quantity of developer is thus made high, the toner could be uniformly regulated and charged in the whole widthwise direction on the sleeve and the pressure regulation by space saving, low cost and highly accurate setting will not be required.
For this purpose, however, the flatness of the support layer must not be made high and the manufacturing process becomes complicated and difficult.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an elastic blade which is high in flatness and a method of manufacturing the same.
It is another object of the present invention to provide an elastic blade having a base layer and an elastic layer provided on the convex surface side of said base layer.
It is still another object of the present invention to provide a method of manufacturing an elastic blade having the step of forming a curved base layer, and the step of thermally securing and shaping an elastic layer on the convex surface side of said base layer.
It is yet still another object of the present invention to provide a developing device having a toner carrying member for carrying a toner thereon, and a regulating blade for regulating the layer thickness of the toner on said toner carrying member, said regulating blade having a base layer and an elastic layer provided on the convex surface side of said base layer, said elastic layer side being urged toward said toner carrying member.
Further objects of the present invention will become apparent from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a developing device.
FIGS. 2A and 2B show an elastic blade.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a cross-sectional view of a developing device according to an embodiment of the present invention.
A regulating blade 4 which is an elastic blade bears against a developing sleeve 3 which is a toner carrying member opposed to a photosensitive member 3 which is an image bearing member bearing an electrostatic latent image thereon, carrying a toner 6 thereon and being rotated, and regulates the layer thickness of the toner and also imparts triboelectricity to the toner by friction.
In the present embodiment, a one-component developer is used as the toner.
The regulating blade 4 bears against the developing sleeve 3 so as to be in a counter direction to the direction of rotation b of the developing sleeve, that is, so that the free end of the regulating blade 4 which bears against the developing sleeve 3 may be upstream of the end of the regulating blade 4 which is fixed to a developer container 2 , with respect to the direction of rotation b.
Description will now be made of the blade 4 of the present embodiment and a method of manufacturing the same.
As shown in FIGS. 2A and 2B, the regulating blade 4 of the present embodiment is of a two-layer construction comprising a support layer 4 a which is a base layer for regulating pressure and an elastic layer 4 b for regulating the amount of charge, and is characterized by a construction in which the elastic layer 4 b is formed on the convex side surface of the support layer 4 a curved in the lengthwise direction thereof and caused by the warp thereof.
The method of shaping this regulating blade adopts a method of integrally thermally securing and shaping the elastic layer on the convex side surface of the support layer. At that time, by selecting such a material that the amount of thermal contraction of the elastic layer is greater than the amount of warp of the support layer and the shape of the support layer after the elastic layer has been thermally secured to the support layer becomes warped toward the elastic layer side, it is possible to make a flat regulating blade.
A member usable as the support layer is a metallic flat plate such as a stainless steel plate, a phosphor bronze plate or an aluminum plate having a thickness preferably in the range of 20 μm-500 μm in connection with the pressure contact force thereof with the developing sleeve, or a flat plate made of resin, for example, a springy hard elastic member such as a polyethylene terephthalate resin plate, a polycarbonate resin plate or a ductile polypropylene resin plate having a thickness preferably in the range of 50 μm-100 μm.
Description will be made here of the warp of SUS (stainless steel) foil or the like. For example, the amount of warp of SUS 60 μm CSP-H material is about 30 mm for a length of 365 mm. The cause of this is the accuracy tolerances of the circumferences of two upper and lower metallic rolls each having a mirror surface when the material is rolled by these two rollers. Therefore, even if the material is wound in advance around a circular paper tube or the like, the direction of warp does not depend on the direction of the winding. Also, the amount of warp of a metal such as SUS depends of the thickness thereof and if the thickness is great, the warp thereof will become small in the relation with the distortion thereof. Also, if a tension-annealed article (an article having its amount of warp modified) is used, the amount of warp will become small for the same thickness (but cost will become higher). Also, in the case of a scroll of resin such as PET, warp is created as a curl when the scroll is formed and therefore, the direction of warp can be made into the direction of winding.
Next, the rubber material of the elastic layer may preferably be HTV silicone rubber (such as high-temperature setting type millable silicone rubber), thermoplastic urethane rubber, liquid-like urethane rubber, liquid-like nitrile butadiene rubber or liquid-like silicone rubber (such as LTV or RTV), or an electrically insulative rubber elalstic material such as a denaturalized material or a blended material of the respective materials.
Also, the method of manufacturing the blade can be achieved by applying an adhesive agent to the convex side surface of the support layer for regulating pressure, integrally thermally securing and shaping the elastic layer for contact with the developer by injection molding, press molding or the like, forming it into a sheet of high smoothness, and thereafter cutting the sheet into any desired dimensions, thereby manufacturing the blade.
The manufacturing method of the present invention is a method of molding the support layer and the elastic layer integrally with each other, and examples thereof include a molding method using a flat plate molding mold using a mirror surface as the upper surface thereof in a flat heat press, to thermoset the elastic layer by heat and pressure and thermally weld it by a primer applied on the support layer (this method is effective when the material of the elastic layer is a material of high viscosity), a molding method of installing the support layer on the outer side in a centrifugal molding machine, applying heat thereto and thermosetting and thermally securing the elastic layer to the support layer while a drum is rotating (this method is effective when the material of the elastic layer is a material of low viscosity), a molding method of pouring a raw material into a metal mold comprising two longitudinally flat plates combined together, and thereafter applying heat thereto, thereby thermosetting the elastic layer and thermally securing it to the support layer (this method is effective when the material of the elastic layer is a material of low viscosity), and a molding method of using an injection molding machine to pour the material of the elastic layer into a flat plate molding metal mold having installed therein the support layer having a primer applied thereto (this method is effective both when the material of the elastic layer is a material of high viscosity and when the material of the elastic layer is a material of low viscosity).
The magnitude of the amount of warp of the support layer is coped with by changing the molding conditions and the shape conditions. For a support layer having great warp, it is effective to cope with by making the thickness of the elastic layer great and increasing the temperature during the formation of the elastic layer (high temperature molding), and for a support layer having small warp, it is effective to make the thickness of the elastic layer small and effect the molding of the elastic material by low temperature molding (this includes a secondary vulcanizing temperature condition). It is also possible to adjust the amount of warp by the time for the heat molding of the elastic layer (for a support layer having a small amount of warp, it is effective to lengthen the vulcanization of the elastic layer, and particularly when the temperature of secondary vulcanization is higher than the temperature of primary vulcanization, it is more effective to lengthen the time for secondary vulcanization).
Description will now be made of experimental examples based on the present invention and a comparative example.
Experimental Example 1
By the warp of stainless steel foil (SUS304CSP-H of a thickness 0.06 mm as a support layer 4 a, a primer for silicone rubber is applied to the convex side surface thereof, and high temperature setting type LTV silicone rubber (Tore Dowcorning, liquid-like silicone rubber (LSR) DY35-7002) is integrally molded thereon at 120° C. for 5 minutes in a metal mold having its upper surface finished into a mirror surface, by an injection molding machine for rubber (produced by Matsuda Works, Ltd.), thereby forming an elastic layer 4 b of silicone rubber having a thickness of 0.4 mm on the unwarped surface side of the stainless steel foil. Thereafter, as secondary vulcanization, it is left at it is in environment of 200° C. for 4 hours. Subsequently, after cooling, the cutting of a regulating blade is effected as shown in FIG. 2B by a cutting machine (a super-cutter produced by Ogino Seiki Co., Ltd.), and the cut blade is used as a blade for regulating the amount of developer.
Comparative Example
The molding method is the same as that in Experimental Example 1, and liquid-like rubber is thermoset on SUS foil of a thickness 0.06 mm by injection molding, and a rubber layer of a thickness 0.4 mm is molded in a metal mold. At this time, a primer is applied to the concave side surface of the SUS foil, and is coated with rubber. Thereafter, it is cut into the dimensions as shown in FIG. 2B by a cutting machine, and the cut product is used as a blade for regulating the amount of developer.
Experimental Example 2
An elastic material sheet is adhesively secured to SUS foil of a thickness 0.06 mm and is molded. At this time, an elastic material sheet already molded by heat molding or the like is adhesively secured to the convex side surface of the SUS foil. As the adhesively securing method at that time, the elastic material is adhesively secured to the SUS foil by the use of a both-surface tape without heat being applied thereto. After the adhesive securing and molding, the molded article is cut as shown in FIG. 2 B and is used.
Experimental Example 3
An elastic material sheet is adhesively secured to SUS foil of a thickness 0.06 mm and is molded. At this time, an elastic material sheet already molded by heat molding or the like is adhesively secured to the convex side surface of the SUS foil. As the adhesively securing method at that time, use is made of a hot melt method of molding by applying heat, and the elastic material is adhesively secured to the SUS foil. After the adhesive securing and molding, the molded article is cut as shown in FIG. 2 B and is used.
TABLE 1
Experimental
Comparative
Example 1
Example
integral
integral
heat
heat
Experimental
Experimental
Adhesively
adhesion
adhesion
Example 2
Example 3
Securing
molding in
molding in
both-surface
hot melt
Method
mold
mold
tape adhesion
adhesion
Surface for
convex side
concave side
convex side
convex side
Adhesive
Securing
Flatness
minute
great
small
small
(Amount of
Float on a
Fixed Board)
Image-
◯
x
Δ
Δ
Density
(end portion)
Irregularity
White Streak
◯
Δ
Δ
Δ
Phenomenon
(end portion)
⊚ image density irregularity → evaluated by the degree of whitening of black density during whole surface solid black output
⊚ white streak phenomenon → evaluated by the degree of creation of while streaks during whole surface solid black output
The result of the image output evaluation effected with the regulating blades molded by the experimental examples and the comparative example being mounted in a copying machine (NP1215 improved machine produced by Canon) is shown in Table 1 above.
By thus providing the elastic layer on the convex side of the base layer, it is possible to increase the flatness of the base layer.
Also as the method of adhesively securing the elastic layer, heat adhesive securing molding is preferable as can be seen from the experimental examples.
While some embodiments of the present invention have been described above, the present invention is not restricted thereto, but all modifications thereof within the scope of the technical idea of the invention are possible. | An elastic blade regulates the layer thickness of a toner used in the developing device of an image forming apparatus such as an electrophotographic apparatus. The elastic blade is manufactured by providing a metal layer consisting of a rolled metal. The metal layer has a warped shape including a convex side caused by rolling the metal layer. A rubber layer is provided only on a surface of the metal layer at the convex side thereof. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to tool boxes, and in particular, to a tool box specifically adapted for use with a step ladder.
Ladders are used extensively to support workers in an elevated position while they perform various tasks. Consequently, numerous devices have been developed expressly for the purpose of supporting articles, such as tools, fasteners, materials, containers, and the like, upon a ladder. In spite of this, a particular limitation of prior art devices is the difficulty in using these devices in environments other than with a ladder. It is believed that applicant's invention, as defined hereinafter, contains novel features particularly useful in assisting a worker in performing a wide variety of tasks, with and without a ladder.
SUMMARY OF THE INVENTION
The present invention addresses the problem of prior art devices by providing a tool box which, while particularly adapted to use with a step ladder, may be used independently of the ladder. The present invention provides an open tool box with a cover positionable over a portion of the box. The cover is also adapted to hook onto the top of a step ladder.
These together with other objects of the invention, along with various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a ladder mate tool box.
FIG. 2 is a side view of the tool box with the cover closed.
FIG. 3 is a perspective view of a step ladder.
FIG. 4 is a side view of the tool box with the cover open and engaged to a step ladder.
DETAILED DESCRIPTION OF INVENTION
Referring to the drawings in detail wherein like elements are indicated by like numerals, there is shown a ladder mate tool box 25 constructed according to the principles of the present invention. The tool box 25 is particularly adapted to engage a step ladder 10 .
The step ladder 10 shown is comprised of at least two, main, upright rails 11 and a number of horizontal steps 12 interconnecting the rails 11 . The tops 13 of the rails 11 usually terminate in a generally flat, rectangular, horizontal platform 14 . The platform 14 has an underside 15 , a top side 16 , two side edges 17 , a forward edge 18 and a rearward edge 19 , said rails 11 terminating in the platform underside 15 near to the rearward edge 19 and side edges 17 . The platform 14 has a pair of downwardly extending legs 20 pivotally attached to the platform underside 15 by means of pivots 21 positioned near to the forward edge 18 and side edges 17 .
The tool box 25 is made out of a sturdy, lightweight material such as plastic or metal and has a generally rectangular base 30 and corresponding cover 50 . The base 30 is comprised of a substantially parallel front 31 and rear 32 walls, substantially parallel side walls 33 and 34 , and a flat bottom 35 extending from the front 31 to rear 32 walls and from side wall 34 to side wall 35 . The longitudinal axis of the base 30 is defined by the side walls 33 , 34 . The base 30 has two divider walls 36 and 37 parallel to the side walls 33 , 34 and extending from the front 31 wall to the rear wall 32 . Other divider walls may be added or subtracted to increase or decrease the number of compartments formed thereby. In this embodiment of the invention, the divider walls 36 , 37 are each positioned approximately one quarter of the longitudinal distance from a side wall 36 , 37 , respectively. The area defined by the divider walls 36 , 37 , front wall 31 , rear wall 32 and bottom 35 is termed the central compartment 39 . The area defined by the side wall 34 , divider wall 36 , front wall 31 , rear wall 32 and bottom 35 is termed an outer compartment 40 . The area defined by the side wall 33 , divider wall 37 , front wall 31 , rear wall 32 and bottom 35 is also termed an outer compartment 41 .
The cover 50 is generally flat and has four edges, a front edge 51 , a rear edge 52 , and two sides edges 53 and 54 , respectively. The cover rear edge 52 is pivotally hinged along its length to the top edge of the base rear wall 32 . The cover 50 has a top surface 55 and bottom surface 56 . An elongated element 57 having a half-round cross section is attached to the top surface 55 near to the cover front edge 51 and extending nearly from side edge 53 to side edge 54 . The element 57 has a central longitudinal axis parallel to the cover front edge 51 . The element 57 has an elongated opening 58 defined by the half-round cross section and extending the length of the element 57 , said opening 58 facing rearward toward the cover rear edge 52 . The element 57 has an external surface 59 and an interior surface 60 accessible through the opening 58 . The cover 50 has a longitudinal axis and width defined by the side edges 53 , 54 . The width of the cover 50 is approximately equal to the distance between the base divider walls 36 , 37 , whereby only the base central compartment 39 may be covered. The base front wall 31 has a latch 38 attached thereto. The cover top surface 55 has a corresponding latch receptacle 65 attached thereto adjacent to the front edge 51 . The latch 38 is adapted to be removably engaged to the latch receptacle 65 .
In operation, the tool box 25 may be used in two different modes. In the first mode, the tool box 25 may be used as a regular tool box with a closable cover. Tools, fasteners, materials, containers, and the like, may be carried in the central compartment 39 . The cover 50 is closable over the central compartment 39 by means of the latching arrangement 38 , 65 . The elongated element 57 with its elongated opening 58 provides a means for carrying the tool box 25 , i.e., fingers may be slipped into the opening 58 against the interior surface 60 while the curved outer surface 59 of the element 57 fits into a person's palm. The outer compartments 40 , 41 are used primarily while performing work. The outer compartments 40 , 41 provide a place to temporarily hold tools, fasteners, materials, containers, and the like, while the central compartment 39 will generally hold those items not immediately required for the task at hand.
In the second mode, the tool box 25 is used in conjunction with a step ladder 10 . The box 25 is opened and the cover 50 is positioned over the step ladder platform top side 16 . The tool box elongated cover element opening 58 is positioned over and engages the platform rearward edge 19 . The tool box base rear wall 32 rests against the step ladder legs 20 . The tool box 25 is thereby open and fully accessible to a worker standing on the step ladder steps 12 . When finished, the worker disengages the tool box cover element 57 , removes the tool box 25 from the step ladder 10 , closes the tool box 25 and removes the tool box 25 to any desired location.
It is understood that the above-described embodiment is merely illustrative of the application. Other embodiments may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof. | An open tool box with a cover positionable over a portion of the box. The cover is adapted to hook onto the top of a step ladder. | 4 |
This is a division of application Ser. No. 422,349, filed 12-6-73, now abandoned.
SUMMARY OF THE INVENTION
The pool is of a construction providing for the complete safety of a child and of a size to overcome a beginning swimmer's fear of a large expanse of water. The limited water expanse gives a child a feeling of security while providing adequate room for swimming movements and travel. The water depth in the tank is uniform and is readily variable to accommodate an elementary class requiring arm support on the pool bottom, or a more advanced class requiring arm clearance with the pool bottom but foot-touching with the pool bottom at all times. The controlled water depth, proximity of the instructor to all children in the pool and the maintaining of instruction control by a numbers system provides for a full enjoyment of the pool, and a willingness to learn swimming due to the absence of fear of the water. The pool is of an all fiberglass construction and relatively light in weight to permit its transport into schools or the like which lack pool facilities but which have a gym or auditorium in which the pool can be readily set up for use with its bottom wall supported directly on a floor surface.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a front perspective view of the swimming pool of this invention;
FIG. 2 is an enlarged plan view of the pool shown in FIG. 1;
FIG. 3 is an enlarged transverse sectional view on line 3--3 in FIG. 2;
FIG. 4 is a diagrammatic plan view showing the modular assembly of the pool of FIG. 1;
FIG. 5 is a perspective view of a module quarter section embodied in the pool, illustrated in FIGS. 1 and 4;
FIG. 6 is illustrated similar to FIG. 4 and shows the pool of FIG. 4 enlarged by module additions thereto;
FIGS. 7, 8 and 9 are perspective views of module sections for enlarging the pool shown in FIG. 4 to the pool size shown in FIG. 6;
FIGS. 10 and 11 are enlarged detail sectional views taken on lines 10--10 and 11--11, respectively, in FIG. 2;
FIG. 12 is a detail exploded perspective view showing the adjacent connectible ends of plate members which form part of a walkway for the pool;
FIG. 13 is an enlarged sectional detail view as seen on line 13--13 of FIG. 2; and
FIG. 14 is a schematic showing of the water circulating system for the pool.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 and 3, the pool of this invention is shown as including an elongated tank 12 of a generally trough shape. Extended laterally outwardly from the upper edge of the tank side wall 13 and both end walls 14 and 16 is a continuous walkway 17 which includes a longitudinal section 18 and transverse end sections 19 and 21. A sectional combination splash board and tank cover assembly 22 is hinged to the opposite side wall 23 of the tank for movement from a tank covering position shown in full lines in FIG. 3 to an upright position shown in FIG. 1 to function as a splash board. A machinery containing housing 24 is located adjacent the walkway end section 21 and is integrally formed with step members 26 for access to the walkway 17 from a floor or ground surface on which the tank is supported.
The tank is of a fiberglass modular construction and is illustrated in FIGS. 1, 2 and 4 as being composed of four quarter modules or sections 27, 27a and 28, 28a, which will be hereinafter referred to as right and left hand modules, respectively. The right hand module 27 (FIG. 5) is integrally formed with a bottom wall 29, a side wall 31 and an end wall 32 that is comprised of a series of step members 33. The open end 34 of the module section 27 terminates in an outwardly extended lateral flange 36 and the open side thereof in a lateral flange 38 that is continuous with the end flange 36.
A left hand quarter section or module 28 (FIGS. 2 and 4) is a mirror image of a right hand module 27 so that when a left hand module and a right hand module are positioned in a side by side relation the adjacent side flanges 38 thereof (FIG. 3) are connectible together by bolt assemblies 39. A left hand module and a right hand module thus together form one half of the tank 12 which is then completed by the assembly therewith of a corresponding one-half tank assembly comprised of a right hand module 27a and a left hand module 28a. These half tank assemblies are connected together at the end flanges 36. As best shown in FIGS. 1 and 4, it is seen that the right hand modules 27, 27a and left hand modules 28, 28a are disposed diagonally of the tank 12.
To reinforce the fiberglass walls of the modules 27, 27a and 28, 28a, the outer surface of the side wall 31 and bottom wall 29 of each module section is provided with longitudinally spaced brace members 41 of a generally right angle shape and formed of a metal pipe material (FIG. 3). These metal brace members 41 are interconnected with longitudinally extended brace members 42 comprised of half sections of cardboard or like composition tubes. The metal brace members 41 and half tube members 42 are rigidly secured to a side wall and a bottom wall by a fiberglass coating or sheet so as to form an integral part of a module. It is to be noted that the brace members 41 and 42 project a distance from the side wall and bottom wall of a module which is substantially equal to the width of an end flange 36 and side flange 38. The tank 12 is thus floor supported on those portions of the flanges 36 and 38 that project downwardly from the bottom wall 29 of a module as best appears in FIG. 3.
For a purpose to appear later, the bottom wall assembly of the tank 12 is marked off in a plurality of designated areas or training stations 43. These stations are arranged in a pair of side by side rows extended longitudinally of the tank, illustrated in FIGS. 1 and 2 as 16 in number and indicated by the numerals 1-16, inclusive.
Each end section 21 of the walkway 17 is comprised of a single plate member of a fiberglass construction. The longitudinal section 18 of the walkway 17 is formed of a plurality of plate members 44, illustrated as four in number in FIGS. 1 and 2, arranged end to end and having the adjacent ends thereof in an overlapped relation. Each side plate member 44 (FIG. 12), in transverse cross section, has an inverted U-shape portion 45 along the outer side thereof and a depending flange 46 at its inner or pool side. One end 50 of a side plate member 44 is of a reduced size in transverse cross section, as indicated at 47 in FIG. 12, relative to the opposite end 50 thereof so that the ends of adjacent side plate members 44 are constructed for assembly in an overlapped nested relation to form a smooth and continuous connection or junction between the plate members 44.
The walkway 17 is supported at each junction of adjacent side plate members 44, and the junction of an outermost plate member 44 with an adjacent walkway section 19 and 21 by a floor carried upright bracket assembly 48 (FIGS. 10 and 11). Each bracket assembly includes a leg member 49 and an arm member 51 projected laterally from the upper end of the leg member and interconnected therewith by a brace member 53. Secured to the leg member and spaced upwardly from the arm member 51 is a horizontal support 52.
The horizontal support member 52 (FIG. 10) is positioned within the U-shape portion 45 at the outer side of a plate member 44 in contact engagement with the base section of such U-shape portion. The depending flange 46 on the inner side of a plate member 44 is positioned in a side by side relation against the inner surface of an upright marginal flange 56 which defines the upper terminal ends of the side wall 31 and end wall 32 of the module sections 27, 27a and 28, 28a. The marginal flange 56 and side plate member flange 46 are secured together by bolt assemblies 57. A horizontal support member 52 and the overlapped ends of adjacent side plate members 44 are secured together by bolt assemblies 58.
These bolt assemblies 58 (FIG. 10) also secure to the outer side of the walkway 17 the base portions 59 of upright posts 61 which form part of an outer guard rail assembly 60 that extends about the outer side of the walkway 17. An inner upright guard rail 65 which extends only along the inner side of the walkway longitudinal section 18 has the legs or posts 62 thereof secured to the walkway by bolt assemblies 63. It is desirable that the walkway 17 be horizontally sloped downardly and inwardly from the outer side to the inner or pool side thereof for water draining purposes.
It is seen, therefore, that the pool 12 is provided at each end thereof with steps 33 formed integrally with the end walls 32 of the modules 27, 27a and 28, 28a; an outer guard rail means 60 extended continuously about the outer side of the walkway 17; and an inner guard rail means 65 extended along only the inner side of the longitudinal section 18 of the walkway 17.
The machinery housing 24 has an open side (not shown) positioned against the walkway end section 21 (FIGS. 1 and 11) so that the end section 21 and the top surface 66 of the housing 24 form a continuous horizontal platform at the top of the steps 26. Hand rails 67 for the steps 26 are connected to the outer side of the walkway end section 21 and to the lowermost one of the steps 26.
The space below the longitudinal section 18 and end section 19 of the walkway 17 is closed by cover plates 68. Each cover plate 68 (FIG. 10) is of a fiberglass construction and of a generally rectangular shape formed with a continuous laterally extended marginal flange 71. A cover plate 68 has secured to that portion of the marginal flange 71 thereof located at its upper side, the horizontal leg 72 of an angle member 73, the vertical leg 74 of which has one side in a plane common to the outer surface of the cover plate 68. The angle member 73 is located within the U-shape portion 45 at the outer side of the walkway 17 with the vertical leg 74 positioned against the inner surface of the outer leg 69 of such U-shape portion to which it is secured by bolt assemblies 76.
The combination pool cover and splash board assembly 22 is comprised of separate section 77 (FIG. 1) that are arranged in an end to end relation longitudinally of the pool. The adjacent ends of these sections 77 are relatively constructed for overlapping engagement when the assembly 22 is in either the open or closed positions therefor. Each cover section 77 (FIG. 3) is pivotally connected by a plurality of hinge units 78 (only one of which is shown). Each hinge unit 78 includes a first hinge plate 79 of a generally J-shape in longitudinal cross section secured to a cover section 77 so that the short leg 81 thereof extends downwardly along one side of a section 77. A second hinge plate 82 of a generally right angle shape in longitudinal cross section, has a horizontal leg pivotally connected at 83 to the short leg 81 of the hinge plate 79 and a vertical leg 84 secured to the upright marginal flange 71 at the tank side wall 23.
When the cover and splash board assembly 22 is in a tank covering position, as shown in FIG. 3, a section 77 extends horizontally of the tank sidewalls 13 and 23 with the free end 86 thereof supported on a horizontal shelf member 87 that interconnects the upright marginal flange 71 and tank side wall 23. As illustrated in dotted lines in FIG. 3, an open position of a cover section 77 is defined by the engagement of the short leg 81 of the hinge plate 79 with the horizontal leg of the hinge plate 82. In its open position the combination cover and splash board assembly 22 is extended upwardly and outwardly from the pool side wall 23 with the lower end thereof located inwardly of the marginal flange 71.
For use in the teaching of children of elementary school age the tank 12 is filled from a suitable source of water (not shown) to a level or height that is substantially knee deep on a child standing on the bottom of the tank or pool. The water is continuously circulated within the pool (FIGS. 2 and 14) by a pump unit 85 having an inlet 88 open to the inside of the pool 12 at a hole 88 (FIG. 1) formed in the back of one of the steps 33 in the end wall 32 in the right hand module 27. Water from the pump outlet 89 (FIGS. 2 and 14) passes successively through a hair trap 91 and a filter 92. From the filter 92 a portion of the water is directed through a heater 93 through a heater inlet pipe 94 while a second portion of the water from the filter bypasses the heater through pipe 96. The bypassed water and the heated water are then brought together into a single pipe 97. A chlorinator unit 98 is shunted across a portion of the pipe 97 for chemically treating the water prior to its admission into the pool 12 from the line 97 through an opening 90 formed in the back member of a step 33 of the left hand module 28a. In use the pool water is maintained at a temperature of from about 85° to 90° F and continuously circulated over the complete area of the pool.
As best appears in FIG. 2, the pump 85, hairtrap 91, filter 92, heater 93 and chlorinator 98 are all carried within the machinery housing 24 so as to be readily accessible for maintenance and service purposes by merely separating such housing from the remainder of the pool assembly.
For draining the pool the only left hand module 28 (FIGS. 2 and 13) is formed in its bottom wall 29 at a position adjacent the lowermost one of the steps 33 with a transversely extended recess or trough 99 provided with a valve controlled drain opening 101. The trough 99 is longitudinally inclined to the drain opening 101.
In using the pool 12 for teaching purposes, children, in number corresponding to the training stations or marked areas 43, are admitted to the pool by use of the steps 26. When in the pool they are assigned to a training station or marked area 43 and for elementary students of an age corresponding to third graders and downwardly, their confinement within a training station 43 is strongly insisted upon. This procedure completely eliminates the grouping of the children into parts, bunches or groups which would, of course, prevent adequate body movement for instructional swimming.
To prevent any embarassment to a child as a result of having his name called too frequently during instruction periods, each child is assigned and then addressed by the number of his training station. With a child in his assigned training station 43, he is first instructed to kneel in the pool and then assume a position with his hands and knees on the pool bottom. In this position he is acclimated to the water by first dipping his face therein and then later by dipping his face and concurrently blowing bubbles. This exercise is then followed by having a child hold his breath and submerging his head for short counts varied at the discretion of the instructor.
When the greater portion, usually about 90 percent of the instructional class, exhibits a free and full acclimation to the water, the children are instructed to hold their bodies horizontally with their hands in finger touching engagement with the bottom of the pool. This exercise is first practiced with the head lifted upwardly out of the water after which the hands are withdrawn from the pool bottom with the head in a full float position. Again when about a 90 percent portion of the class is capable of performing a full face float, the class is instructed to return to the horizontal body position with the hands in finger touching engagement with the pool bottom, and with faces uplifted are taught stiff leg kicking movements.
When these leg kicking movements are learned, the children are permitted to finger tip along the pool bottom, with faces exposed, up one row of the training stations 43 and down the other row thereof, while utilizing the kicking movements they have learned. During this travel up and down the pool 12, the children are encouraged to cup their hands as often as possible without touching the pool bottom to help them acquire a dog paddle arm movement.
Again, when about 90 percent of the class is able to dog paddle around the pool, over-arm swimming movements are taught while the children are standing on the pool bottom in their assigned training stations. On learning the over-arm swimming movements in a standing position, the children are permitted to combine such arm movements with the previously learned leg movements for swimming up and down the pool. In this connection, it will be appreciated that the swimming instructions are repetitive and progressive so that a more advanced exercise is undertaken only after prior lessons have been learned. The exercises are thus acquired at a leisurely pace so that the swimming actions follow in a natural and orderly procedure.
By virtue of the relatively small water expanse in the pool and the fact that the bottom of the pool is always in touching engagement with either the feet or finger tips, fear of the water is completely eliminated so as to provide full attention to the swimming instructions.
In one embodiment of the invention the tank 12 is about 36 feet long and 51/2 feet wide, with an over-all height of about 38 inches. Each module 27, 27a and 28 and 28a is about 33 inches wide and 18 feet long with a bottom wall length of about 15 feet. The walkway 17 is about 2 feet wide, with a side plate member having a length of about 9 feet.
If it is desired to lengthen the pool, a module section 102 (FIG. 7) and a mirror image thereof, indicated at 102a in FIG. 6, are connectible between longitudinally opposite ones of the left and right hand modules 28, 28a and 27 and 27a, respectively. If the pool 12 is to be widened, such is accomplished by the insertion of a module 103 between transversely opposite ones of the module 27, 27a, and 28, 28a (FIGS. 6 and 8). If it is desired to concurrently lengthen and widen the pool 12, the modules 102, 1022 and 103 are used concurrently with a module 104, shown in FIG. 9, which consists entirely of only a bottom wall. It will be appreciated that the modules 104 will be arranged between transversely opposite ones of sections 102 and 102a so as to constitute floor extensions for the bottom wall portions of the modules 103.
In the above embodiment of the pool 12, the modules 102 and 102a are about 15 feet long and 33 inches wide; the module 103 about 18 feet long and 33 inches wide with a bottom wall length of 15 feet; and a module 104 is 15 feet long and 33 inches wide.
Although the invention has been described with respect to a preferred embodiment thereof, it is to be understood that it is not to be so limited and that changes and modifications can be made therein which are within the full intended scope of this invention as defined by the appended claims. | The pool is of an elongated trough shape and formed of connectible units or modules each of which has cross sectional dimensions providing for its passage through usual size school doors. The water is of a uniform depth over the full length of the pool such that a child may finger tip the bottom anywhere in the pool and is continuously heated, filtered and circulated. The bottom of the pool is marked with numbered training stations with a swimmer in a training station being addressed by the station number. Instructions may be given from within the pool or from a horizontal walkway extended outwardly from the upper edge of the pool. | 4 |
BACKGROUND OF THE INVENTION
The invention is directed to a method for the transmission of information packets between a source LAN emulation client LEC of a first ELAN and an LAN emulation client of a second ELAN.
ELAN stands for emulated LAN as described, in particular, in the specification 94-0035R9, "LAN Emulation Over ATM: Version 1.0" of the LAN Emulation SWG Drafting Group of the ATM Forum of Jan. 6, 1995, Bill Ellington, editor. This is thereby an approach of the ATM Forum to the migration of current LANs to ATM networks. ATM thereby means "Asynchronous Transfer Mode", i.e. asynchronous data or, respectively, information transmission methods. LAN is an abbreviation of "Local Area Network". LANs are datagram-oriented local networks that are described in, among other references, the article by David D. Clark, Kenneth D. Progran and David P. Reed, "An Introduction to Local Area Networks" in Proceedings of the IEEE, Vol. 66, No. Nov. 11, 1978, pages 1497 through 1517. LANs are also described in ISO/IEC TR 8802-1, "Overview of LAN-Standards". LANs offer a connectionless service, what is referred to as the MAC service. MAC thereby stands for "Media Access Control". By contrast to this connectionless service, ATM technology is connection-oriented. When the protocols of the higher layers developed for LANs are to be used in emulated LANs on the basis of an ATM network, the properties of the connectionless MAC service must be produced in this ATM network. The LAN emulation according to the aforementioned specification realizes the MAC service in the local ATM network and thus defines a single emulated LAN, called ELAN below. The standard LAN protocols such as LLC, TCP/IP, SPX/IPX or TP/CLNP can be used in this ELAN.
The LAN emulation supports the two most frequently employed AN standards, namely Ethernet according to IEEE 802.3 and Token ing according to IEEE 802.5, whereby three frame lengths are supported given token ring. The addressing of every LAN station ensues on the basis of a destination MAC address that is unambiguous worldwide. For the transmission of information between LANs, the address is handed over from a high layer are. For the description of the information path, token ring LANs employ what are referred to as route descriptors in the frame header in addition to MAC addresses. The frame can be conveyed to the destination within token ring LANs on the basis of such a descriptor.
Only MAC addresses shall be mentioned below.
For emulation of an LAN in an ATM network, the LAN emulation must, among other things, resolve destination MAC address into destination ATM addresses, realize multicast and broadcast, i.e. a distribution of information to as plurality of or to all subscribers, as well as assure the transmission of LAN emulation frames in the proper sequence.
The LAN emulation has a client-server configuration. The client side is called LAN emulation client LEC and the server side is called LAN emulation service. The LAN emulation service is composed of LAN emulation server LES, broadcast-and-unknown server BUS and LAN emulation configuration server LECS. The LAN emulation client receives the destination MAC address from a higher-ranking layer, for example the LLC layer, and must find the corresponding ATM address, in order to subsequently initiate the setup of a direct ATM connection to the destination by signalling. The signalling can thereby ensue, for example, according to the ITU-T Recommendation Q.28311Q.2971. An LAN emulation client can be realized in the software or in the hardware of the stations that participate in the LAN emulation.
An LAN emulation server LES maintains a table with all MAC addresses that are reported in the emulated LAN, for example in the framework of a configuration, and with the corresponding ATM addresses. The communication between the LAN emulation clients and the LAN emulation client ensues according to an LAN emulation address resolution protocol that, conforming to the English designation LAN Emulation Address Resolution Protocol, is referred to as LE -- ARP. When an LAN emulation client does not know the destination ATM address of a destination MAC address, then it sends an inquiry with the destination MAC address to the LAN emulation server. Such an inquiry for address resolution is referenced LE -- ARP request. When the LES can resolve the destination ATM address, it replies with LE -- ARP response. When it cannot, it sends the request to further LAN emulation clients.
When an LAN emulation client receives an address resolution response LE -- ARP response, then it sets up an ATM-UBR connection to the ATM address contained therein and sends a unicast frame. UBR thereby denotes "Unspecified Bit Rate", i.e. indicates that the bit rate is not specified. A unicast frame is an information or, respectively, data packet with a single addressee. In the transmission of frames within an ELAN, a distinction is made between unicast frame to one receiver and multicast or broadcast frame to several or all receivers. An ATM-UBR connection is maintained for 20 minutes from the last transmitted frame so that further frames can be sent to the same receiver in a simple way. To this end, the variable C12 is referenced in point 5.1.1 of the LAN emulation specification. The destination ATM addresses of destination MAC addresses is stored for a certain length of time in the LAN emulation client with the assistance of a cache mechanism. When there is no connection to a destination LAN emulation client but the destination ATM address is known in the sender LAN emulation client, a sender LAN emulation client LEC can set up a connection without address resolution request and send a unicast frame.
Multicast frames to a group of subscribers or, respectively, LAN emulation clients and broadcast frames to all subscribers or, respectively, LAN emulation clients LECen are sent to the aforementioned BUS. Within an ELAN, the BUS maintains connections to all LEC for the arrived frames to the addressees.
Every LAN can be reported as what is referred to as proxi-LEC. A proxi-LAN emulation client receives all address resolution requests LE -- ARP request that an LES cannot resolve. A proxi-LEC also receives all multicast and all broadcast frames.
The advantage of ATM technology is to be seen, among other things, therein that direct connections with flexible bandwidth can be set up between the communication parties. Such direct connections guarantee minimum time delays and a high information transmission rate. This advantage of ATM technology is utilized in the LAN emulation for unicast frames. Various concepts for connecting local ATM networks such as, for example, ELANs via a wide-area ATM network are known in the article, "Interconnect Emulated LANs with Wide Area ATM networks" by Peter T. P. Chang and Bill Ellington, ATM Forum Technical Committee of November 29 through Dec. 2, 1994. In a first concept, a plurality of ELANs are thereby connected to a wide-area ATM network, whereby the address resolution and the data transmission are undertaken via a single LAN emulation server and a single BUS. This concept leads to an enormous traffic volume for the realization of the broadcast function. The address resolution delay times in such a network are extremely high.
A further concept provides that ELANs be respectively connected to a wide-area ATM network via remote bridges. Either all remote bridges are thereby connected to one another via permanent virtual circuits PVC or the remote bridges are dynamically connected to one another with the assistance of an ATM signalling upon employment of an address resolution server. The transmission possibilities are thereby limited by the transmission possibilities of the remote bridges and the bandwidth of the permanent virtual circuits between two remote bridges. The remote bridges are flooded with broadcast and unknown servers of remote ELANs insofar as the remote bridge thereof does not respectively know the address of the remote bridges allocated to the destination MAC addresses.
A further concept provides that, instead of remote bridges, routers be provided, a mixture of bridge and router. In this case, these routers fulfill the function of an LAN emulation bridge at the ELAN side and fulfill the functions of a router at the side of the ATM wide-area network. As a result thereof, the broadcast problems are reduced; however, a limitation of the transmission possibilities via the ATM wide-area network due to the transmission possibilities of the routers and of the permanent virtual circuits continues to exist.
A further concept provides that the LAN emulation servers of the individual ELANs as well as the BUS of the individual ELANs be connected to one another by direct connections. This, however, leads to a great plurality of direct connections and to a high traffic volume between the LAN emulation servers and the BUS of the individual ELANs. The traffic volume thereby increases linearly with the plurality of connected ELANs. A further concept provides that the LAN emulation servers of the individual ELANs as well as the BUS of the individual ELANs be connected to a higher-ranking LAN emulation server or, respectively, to a higher-ranking BUS via direct connections. This, however, likewise leads to a great plurality of direct connections and to a high traffic volume. The multilayer nature of BUS and higher-ranking BUS or, respectively, LES and higher-ranking LES also leads to time delays.
SUMMARY OF THE INVENTION
An object of the invention is to offer a method for the communication of information packets between a source LEC of a first ELAN and a destination LEC of a second ELAN.
When, within an ELAN, information is to be transmitted from one LAN emulation client to another LAN emulation client, the source LEC usually initiates an ATM connection setup to the destination LEC. The destination ATM address is required therefor. The source LEC knows a destination MAC address from higher layers. Moreover, a destination ATM address for the destination MAC address can be deposited in its memory. When no destination ATM address is deposited, the source LEC normally forwards an address resolution request LE -- ARP -- Request to an LAN emulation server of the ELAN. When the client allocated to the destination MAC address does not belong to the ELAN of this LAN emulation server, this LAN emulation server cannot resolve the ATM address, i.e. cannot answer the address resolution request.
Inventively, the first and the second ELAN are connected to a wide-area network (regionally and/or globally) that offers a connectionless service such as, for example, SMDS (Switched Multi-megabit Data Service) or CBDS (Connectionless Broadband Data Service). Insofar as no explanations to the contrary are provided, what is always meant for the sake of simplicity below and in the patent claims by wide-area network is a wide-area network offering a connectionless service, i.e. a CLS wide-area network (regional and/or global).
When the destination MAC address to be resolved is allocated to at least one LAN emulation client of a second ELAN, then the information transmission is inventively enabled with the following method steps:
determination of the destination ATM address by transmission of an address resolution request of the source LEC to the ELAN via a CLS wide-are network offering a connectionless service and resolution of the destination MAC address in the second ELAN into the appertaining ATM address;
initiation of a connection setup between source LEC and destination LEC via an ATM network ranking higher than the first ELAN and the second ELAN upon employment of the identified destination ATM address;
transmission of the information packets via the higher-ranking ATM network.
In one exemplary embodiment, the identified ATM address is transmitted via the CLS wide-area network as address resolution response to the first ELAN and is transmitted thereat to the source LEC, and the source LEC initiates a connection setup to the destination LEC.
Preferably, the destination ATM address is thereby resolved with the following method steps:
encapsulation of the address resolution request present in the first ELAN as ELAN frame in a frame format of the CLS Wide-area network with an E-164 address allocated to the destination MAC address in the frame header part;
handing over this encapsulated address resolution request to the CLS wide-area network and transmission to the second ELAN;
de-encapsulation of the encapsulated address resolution request and handover to an LAN emulation server of the second ELAN in the ELAN frame format;
resolution of the destination MAC address into an appertaining ATM address by this server of the second ELAN and output of an address resolution response;
encapsulation of this address resolution response into the frame format of the CLS wide-area network and transmission to the first ELAN;
de-encapsulation of the encapsulated address resolution response and handover to the source LEC.
When a single destination LEC is allocated to the destination MAC address, i.e. the transmission of unicast frames is planned, then, according to the aforementioned "LAN-Emulation over ATM-Specification", an address resolution request is sent from the source LEC to the LAN emulation server of the local ELAN. Since the LAN emulation server only knows the local ATM addresses, it cannot resolve the destination ATM address. The local LAN emulation server therefore hands over the address resolution request of the source LRC to all proxi-LEC signed on in the local ELAN. In a beneficial development of the invention, the individual ELANs are therefore respectively connected via a specific LAN emulation client to the wide-area network offering a connectionless service. This access LEC is respectively preferably signed on as proxi-LEC in its ELAN.
When the destination MAC address to be resolved is allocated to at least one LAN emulation client of a second ELAN, then the address resolution request is inventively transmitted to the second and, potentially, to further remote ELANs via the CLS wide-area.
When the individual ELANs are respectively connected via an access LEC to the network offering a connectionless service, then the transition between an ELAN and the CLS wide-area network is preferably formed by an interworking function IWF that is arranged between the CLS wide-area network (T-reference point) and an access LEC of the respective ELAN. Such an interworking function can be a bridge or a router.
A bridge as interworking function has, for example, an address memory for MAC addresses of the ELAN and E.164 addresses of the CLS wide-area network allocated to one another and a memory for an E.164 address allocated to the transition from the CLS wide-area network to the bridge.
A simple embodiment of such a bridge can provide that address resolution request frames and unicast as well as multicast data frames are discarded when no allocated E.164 address is stored for their destination MAC address in the address memory, that address resolution request frames and unicast as well as multicast data frames are forwarded to the CLS wide-area network when an allocated E.164 address for their destination MAC address is stored in the address memory, and that data frames and address resolution request frames whose destination MAC address is a local broadcast MAC address are discarded. Respectively in common with the frame, the conversion function hands over the E.164 address belonging to the destination MAC address to the interface to the CLS wide-are network. The conversion function also hands over the E.164 address allocated to the source MAC address, at least for address resolution requests frames. Frames coming from the CLS wide-area network are handed over to the interface (layer LEC) to the ELAN.
Such a conversion function provides that only address resolution requests for MAC addresses that are deposited in the address memory in common with the allocated E.164 address can be resolved. As a result thereof, only address resolution requests that are sure to be resolved proceed into the CLS wide-area network.
When address resolution requests for MAC addresses whose allocated E.164 addresses are not deposited in the address memory should also be capable of being resolved, then said conversion function can be configured in order to forward address resolution request frames for whose destination MAC address no E.164 address (global E.164 group address) is stored in the address memory to the CLS wide-area network with a global E.164 group address allocated to all ELANs. Controlled, for example, by the group address agent GAA of the CLS wide-area network, such an address resolution request is then sent to all ELANs. Since the address resolution request frames are small, the CLS wide-area network is only slightly burdened by this measure.
Particularly for preventing the sending of unicast data frames in the CLS wide-area network whose Atm address was not known to the source LEC upon dispatch and that therefore proceed to the access LEC as unknown data frames via the broadcast and unknown server, it can be provided in a modification of the disclosed conversion function that all unicast data frames be discarded. Since the address resolution request frame allocated to such a unicast data frame without ATM address is transmitted via the CLS wide-area network, the source LEC receives the ATM address required for an ATM connection setup and can initiate the connection setup. When a protection mechanism of a higher layer determines that a faulty transmission of at least the unknown data frame is present, a repeated transmission via the an ATM connection can ensue.
A described conversion function can preferably be configured in order to forward data frames and address resolution request frames whose destination MAC address is a global broadcast MAC address to the CLS wide-area network. The E.164 address allocated thereto corresponds to the aforementioned E.164 address that addresses all connected ELANs. This measure makes it possible to designationally transmit broadcast frames via the CLS wide-area network even though local broadcast frames are discarded.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention which are believed to be novel, are set forth with particularity in the appended claims. The invention, together with further objects and advantages, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in the several Figures of which like reference numerals identify like elements, and in which:
FIG. 1 shows the transmission of LE -- ARP request/response by the CLS network and ATM connection setup from the sender to the receiver.
FIG. 2 shows the resolution of the multicast/broadcast destination MAC address by the CLS network and setup of point-to-point or point-to-multipoint ATM connections from the sender to all receivers.
FIGS. 3A-C respectively show a protocol stack given coupling of ELANs by SMDS network or, respectively, CBDS network.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The connectionless service or CLS service can be realized with various technologies (for example, DQDB, ATM, FR). The service is described in the ITU-T Recommendation F.812. Known realizations are the switched multi-megabit data service (SMDS) described in specifications of Bellcore, SMDS Interest Group (SIG) and European SMDS Interest Group (ESIG), as well as the connectionless broadband data service (CBDS) defined in ETSI Standard 300 217 and ITU-T Recommendation I.364. CLS has become widespread worldwide due to these realizations. Systems that offer this service are built by many manufacturers in the field of telecommunication.
The service is envisioned for worldwide data communication. At every access to the CLS network, one or more CLNAP addresses according to E.164 (E.164 address) are assigned (CLNAP=connection network access protocol).
A destination CLNAP address (E.164 address) is attached (encapsulation) to an incoming unicast frame with static or dynamic allocation tables on the basis of its destination MAC address and the encapsulated frame (also called CLS packet) is conducted to this CLNAP address.
For better understanding, the addresses in the ELAN are called unicast or, respectively, multicast/broadcast MAC addresses, but individual and group addresses shall be referred to in the CLS network.
Each CLS packet is transmitted independently of the others in the CLS network. The networks sees to the proper sequence of the CLS packets.
Under certain conditions (see prETS 300 478, 300 479), the CLNAP PDUs are encapsulated in CLNIP PDUs (CLNIP=connectionless network interface protocol).
The handling of multicast traffic in the CLS network is realized in the following way. What are referred to as group address agents (GAAs) contain tables with the individual CLNAP addresses that belong to a CLNAP group address. Each CLS packet that has a group address as destination address is conducted to the corresponding group address agent. When encapsulation was carried out, the same group address resides in the fields "CLNAP destination address" and "CLNIP destination address".
The GAA resolves the group address of the incoming CLS packet into individual CLNIP addresses, generates copies of the original packet and attaches to corresponding individual address to each copy as CLNIP address.
The "CLNAP destination address" field remains unmodified, so that the receiver can learn about the original group address. The LAN emulation describes an individual emulated LAN. No solutions are currently known for the coupling of ELANs. For performance reasons, the mechanisms described in the LAN emulation for address resolution and for the realization of multicast/broadcast in the WAN region cannot simply be transferred.
Methods for coupling ELANs upon application of the invention are described below:
A first example provides the transmission of address resolution requests or, respectively, address resolution responses LE -- ARP Request/Response by a network offering a connectionless service and, subsequently, an ATM connection setup from sender to receiver.
An advantage of the LAN emulation is the setup of a direct Atm connection between sender and receiver, as referenced with data direct VCC in the LAN emulation specification. The improvement of the invention of this example therefore proposes that the destination MAC address for the unicast traffic be resolved into the ATM address upon employment of a network such as, for example, SMDS or CBDS that offers a connectionless service and that a direct ATM connection to the destination then be set up.
In the same way, FIGS. 1 and 2 show three ELANs ELAN1, ELAN2 and ELAN3 respectively having an LAN emulation server LES, an ATM switching means ATMS, an LAN emulation client LEC A, LEC B, LEC and a specific LAN emulation client LEC Z1, LEC Z2, LEC Z3 that is referred to below as access LEC and that enables then respective ELAN ELAN1, ELAN2 or, respectively, ELAN3 to have access via a customer premises equipment CPE to a network CLSnet (also shown) that offers a connectionless service. Each customer premises equipment CPE thereby has an interworking function IWF allocated to it for the conversion of a destination MAC address into an E.164 address of the customer premises equipment CPE of the ELAN in which the LAN emulation client to whom the destination MAC address is allocated is located or for the conversion of an E.164 group address of all ELANs. In the exemplary embodiments of FIGS. 1 and 2, the network CLSnet offering a connectionless service is realized with the assistance of a higher-ranking (spatially higher-ranking, i.e. regional or global) ATM network with ATM switching equipment ATMS. The type of realization of the network CLSnet offering a connectionless service, however, has no influence on the invention.
The broadcast and unknown server BUS1, BUS2, BUS3 of the ELAN1, ELAN2 and ELAN3 are also respectively shown in FIG. 1. As shown by an overlapping frame, access LEC, interworking function IWF and customer premises equipment CPE in the illustrated example respectively form a bridge whose bridge function is the interworking function IWF.
The network CLSnet offering a connectionless service contains a server (connectionless server) CLS offering a connectionless service and a group address agent GAA.
In FIG. 1, the signal flows of the address resolution requests LE -- ARP Request and address resolution responses LE -- ARP Response communicated in the framework of the LAN emulation address resolution protocol LE -- ARP are indicated by a thin line with arrow in signal flow direction. The signal flow of data from the LAN emulation client LEC A to the LAN emulation client LEC B via an Atm connection is indicated in FIG. 1 with a bold face line with arrow in signal flow direction.
Accordingly, it can be seen in FIG. 1 that an address resolution request LE -- ARP Request from the LAN emulation client LEC A of the ELAN1 is transmitted via the ATM switching equipment ATMS of this ELAN1 to the LAN emulation server of the ELAN 1 and from the latter via the ATM switching equipment ATMS to the access LEC LEC Z1. From the access LEC LEC Z1, the address resolution request LE -- ARP proceeds to the customer premises equipment, is converted into a different form therein and transmitted via a connectionless server CLA, an ATM switching equipment ATMS and another connectionless server CLA to the group address agent GAA, and is transmitted from the latter directly to the customer premises equipment CPE of the ELAN3 as well as to the customer premises equipment CPE of the ELAN2 via a further ATM switching equipment ATMS and a further connectionless server CLS. In each of the ELANs ELAN2 and ELAN3, the address resolution request LE -- ARP Request is then transmitted to the LAN emulation server LES2, LES3 of the ELAN via an IWF and an access LEC LEC Z2, LEC Z3. The LAN emulation server LES2 of the ELAN2 can resolve the destination MAC address into the ATM address and communicate it to the LAN emulation client LEC A via the ATM switching equipment ATMS, the access LEC LEC Z2, the customer premises equipment CPE of the ELAN2, two connectionless servers CLS of the network CLSnet offering a connectionless server, the customer premises equipment CPE of the ELAN1, the access LEC LEC Z1 of the ELAN1 and the ATM switching equipment ATMS of the ELAN 1.
When the LAN emulation client LEC A knows the destination ATM address, it can set up a direct connection to the destination LAN emulation client LEC B in the ELAN2 via an ATM network illustrated in FIG. 1 by a plurality of ATM switching equipment ATMS, as shown in FIG. 1 by bold face lines between the LAN emulation client LEC A and the LAN emulation client LEC B as well as intervening ATM switching equipment ATMS.
An LAN emulation client LEC Z1, LEC Z2 or, respectively, LEC Z3 of each emulated LAN ELAN1, ELAN2, ELAN3 has access (CPE) to a network CLSnet offering a connectionless service. When the LAN emulation client LEC A of the ELAN1 would like to send a unicast frame to the LAN emulation client LEC B of the ELAN2 but does not know the destination ATM address, it sends an address resolution request LE -- ARP Request to the LAN emulation server LES of the ELAN1. When the LAN emulation server LES of the ELAN1 has no entry for the destination MAC address in its table, it must forward this address resolution request LE -- ARP Request to the access LEC LEC Z1 of the ELAN1. For example, this can be realized by signing the access LEC LEC Z1 on as proxy at the LAN emulation server LES of the ELAN1.
Like the other access LECs LEC Z2, LEC Z3 of the other emulated ELANs ELAN2 and ELAN3, the access LEC LEC Z1 of the ELAN1 is respectively conneted to a customer premises equipment of a network CLSnet offering a connectionless service. The transition from the access LEC LEC Z1, LEC Z2, LEC Z3 to a network CLSnet offering a connectionless service is thereby realized with the assistance of an aforementioned interworking function IWF described in greater detail later that transforms every address resolution request LE -- ARP Request or, respectively, address resolution response LE -- ARP Response that arrives at an access LEC LEC Z1, LEC Z2, LEC Z3 and for which it has an entry (E.164 address) for the destination MAC address into the format of a packet (CLNAP packet) of the network CLSnet offering a connectionless service and hands this request or, respectively, response over to the network CLSnet offering a connectionless service.
When the interworking function has no entry, it can either discard the corresponding address resolution request frame or, respectively, address resolution response frame or provide this frame with an E.164 group address with which all emulated LANs that have an access to the network CLSnet offering a connectionless service can be reached. In the latter instance, a group address agent GAA resolves this group address into the individual E.164 addresses of the individual customer premises equipment CPE of the individual ELANs ELAN1, ELAN2, ELAN3.
It is thereby especially beneficial when the E.164 group address that an interworking function attaches to an address resolution request or, respectively, address resolution response respectively contains the E.164 addresses of the customer premises equipment CPE of all emulated LANs ELAN2, ELAN3 that are connected to the network CLSnet offering a connectionless service, with the exception of the E.164 address of the customer premises equipment of its own ELAN ELAN1.
The group address agent GAA resolves the E.164 group address and sends copies of the packet with the address resolution request LE -- ARP Request to said group of customer premises equipment CPE of the individual ELANs ELAN2, ELAN3. As a result thereof, all access LECs LEC Z2, LEC Z3 receive the address resolution request LE -- ARP Request via the interworking function. Each access LEC LEC Z2, LEC Z3 recognizes the frame type as address resolution request and therefore sends the frame to the LAN emulation server LES of its emulated LAN ELAN2 or, respectively, ELAN3. Usually, any LAN emulation server LES can resolve the unicast destination MAC address of the destination LAN emulation client LEC B into the ATM address.
The return of an address resolution response is especially beneficially configured when the address resolution request LE -- ARP Request has the E.164 address of the customer premises equipment CPE of the output ELAN ELAN1 attached to it upon encapsulation by the interworking function, when, upon de-encapsulation of the address resolution request, the output E.164 address of the address resolution request is stored in the customer premises equipment CPE of the ELAN2, and this output E.164 address, upon encapsulation of the address resolution response handed over by the LAN emulation server LES of the ELAN2 to the customer premises equipment CPE of the ELAN2 via the access LEC LEC Z2, is attached to the header part of the packet to be transmitted via the network CLSnet offering a connectionless service. As a result thereof, an immediate transmission of the address resolution response LE -- ARP Response in encapsulated form to the customer premises equipment CPE of the ELAN1 is enabled by the network CLSnet offering a connectionless service.
The access LEC LEC Z1 in the output ELAN ELAN1 forwards the address resolution response LE -- ARP Response to the output LEC LEC A after this has been encapsulated by the interworking function. After the output LEC LEC A has received the address resolution response LE -- ARP Response with the destination ATM address, it sets up a direct ATM connection to the destination LEC LEC B via a regional or, respectively, global ATM network.
No modifications in the existing LAN emulation specification are required for the realization of the disclosed method for the coupling of ELANs. An access LEC must merely be signed on as proxy at the LAN emulation server LES and be connected via a customer premises equipment CPE to a network CLSnet offering a connectionless service. This access LEC then receives all unanswered address resolution requests LE -- ARP Request from the LAN emulation server LAN of the corresponding, emulated LANs ELAN1, ELAN2, ELAN3.
The existing networks such as, for example, SMDS or CBDS offering a connectionless service also need not be modified either in terms of their standards or in terms of their specifications. An E.164 group address with all individual CPE addresses with which emulated LANs can be reached must merely be defined within this network. A mechanism can thereby be potentially provided that precludes an addressing of the sending customer premises equipment CPE.
A second example of a connection setup explained in greater detail below with reference to FIG. 2 provides for the address resolution of a multicast/broadcast destination MAC address by the CLS network and the setup of point-to-point or, respectively, point-to-multipoint ATM connections from the sender to the receivers.
The basic idea is thereby to learn the ATM addresses of a plurality of receiver LAN emulation clients LEC B. LEC C with LE -- ARP Request for a multicast/broadcast MAC address and to set up point-to-point or point-to-multipoint ATM connections to these LAN emulation clients LEC B, LEC C.
FIG. 2 shows the same network configuration as FIG. 1. The signal flow of the address resolution request LE -- ARP Request ensues in the same way as described in conjunction with FIG. 1. Since, however, a multicast/broadcast MAC address whose group members are the LAN emulation clients LEC B and LEC C in the ELANs ELAN2 and ELAN3 is to be resolved, an address resolution response LE -- ARP Response is transmitted to the source LEC LECA in the ELAN1 not only from the LAN emulation server LES of the ELAN2, as in the example described with reference to FIG. 1, but is also transmitted from the LES of the ELAN3. After receipt of all address resolution responses LE -- ARP Response, a point-to-multipoint connection setup to the LAN emulation clients LEC B and LEC C is initiated from the source LEC LEC A. The connection setup within the network is thereby shown by the bold face solid lines with arrow point in the direction of the connection setup.
As in the preceding example, the access LEC LEC Z1, LEC Z2, LEC C3 is respectively signed on as proxy at the LAN emulation server LES of its ELAN ELAN1, ELAN2, ELAN3 for the realization of the example described with reference to FIG. 2 in order to receive all unanswerable address resolution requests from the LAN emulation server LES.
Differing from the preceding example, a multicast/broadcast MAC address is resolved here. The LAN emulation specification forbits the transmission of LE -- ARP Requests for the resolution of multicast MAC addresses. This limitation must be revoked.
The LE -- ARP Request for the broadcast MAC address 48×"1", i.e. the number "1"48 times, supplies the ATM address of the local broadcast-and-unknown server BUS. A global broadcast MAC address with which all LAN emulation clients of all ELANs that are linked to the CLS network can be addressed must be additionally defined.
The interworking function IWF is commented on in general below:
The IWF realizes the connection between the "access LEC" on the one hand and the CLS network on the other hand. The IWF for the coupling of ELANs by the CLS network handles MAC and E.164 addresses and is to be allocated to layer 2 according to the OSI reference model. I.e., the IWF is an ELAN-CLS bridge.
When the IWF is also to fulfill routing functions, it can also handle layer 3 addresses (for example, IP, IPX, etc.). This, however, is not required for the realization of the methods of the invention.
The protocol stack for coupling ELANs by the SMDS network or, respectively, by the CBDS network is respectively shown in the example in FIGS. 3A, 3B and 3C. The SMDS service is realized with the DCDB technology in the example according to FIG. 3A and is realized with the ATM technology in the example according to FIG. 3B. The CBDS service is realized with the ATM technology in the example according to FIG. 3C.
The IWF has the following jobs:
I. Readying the following parameters:
I.1. Receiver E.164 address
To this end, the IWF must maintain a table with MAC addresses and the corresponding E.164 addresses. For example, the entries in the table are set by network management but can also be filled out on the basis of the sender MAC address and sender E.164 address of the arrived CLS packets and be deleted after a certain time.
I.2. Sender E.164 address
This is the E.164 address of the IWF.
II. Handling the frames according to the destination MAC address:
II.1. Unicast/multicast LE -- ARP Requests/Responses for which no entry is present are either discarded or provided with a global E.164 broadcast group address and routed to the CLS network.
II.2. Unicast/multicast LE -- ARP Requests/Responses for which an entry is present are handed over to the CLS network.
II.3. Frames with local broadcast MAC address Idata and LE -- ARP Requests) are discarded.
II.4. Unicast/multicast LE -- ARP Requests/Responses with global broadcast MAC address are provided with the global E.164 group address and routed to the CLS network.
Only LE -- ARP Requests/Responses are relevant for the realization of the present invention.
A first realized example for the incorporation of an above-described interworking function between an ELAN and a wide-area network offering a connectionless service for that case wherein the connectionless service is a "switched multi-megabit data service" SMDS and the wide-area network for the realization of this service is a "distributed queue dual bus" DQDB can provide that--at the wide-area network side--the protocol layers
SMDS interface protocol layer 1, SIP -- 1,
SMDS interface protocol layer 2, SIP -- 2, and
SMDS interface protocol layer 3, SIP -- 3 are provided and that the interworking function communicates at the wide-area network side with the SMDS interface protocol layer 3, SIP -- 3.
At, for example, the ELAN side, the protocol layers
physical layer, PHY,
asynchronous transfer mode layer, ATM,
asynchronous transfer mode adaption layer-5, AAL5, and
LAN emulation client layer, LEC, are provided, whereby the interworking function communicates at the ELAN side with the LAN emulation client layer, LEC.
In another example, the connectionless service can be a "switched multi-megabit data service" (SMDS) and the wide-area network for the realization of this service can be an ATM network, whereby the protocol layers physical layer, PHY, asynchronous transfer mode layer, ATM, segmentation and assembling sub-layer of the asynchronous adaption layer-3/4, AAL3/4SAR, and SMDS interface protocol layer 3, SIP -- 3 are provided at the wide-area network side, and whereby the interworking function communicates at the wide-area network side with the SMDS interface protocol layer 3, SIP -- 3.
In a further example, the connectionless service can be a "connectionless broadband data service" CBDS, and the wide-area network for the realization of this service can be an ATM network, whereby--at the wide-area network side--the protocol layers
physical layer, PHY,
asynchronous transfer mode layer, ATM,
asynchronous transfer mode adaption layer-3/4, AAL3/4, and
connectionless network access protocol layer, CLNAP, are provided, and whereby the interworking function communicates at the wise-area network side with the connectionless network access protocol layer, CLNAP.
The meanings of the abbreviations employed are recited below in the form of the technical terms according to the applicable standards:
______________________________________AAL ATM adaptation layerATM asynchronous transfer modeBUS broadcast and unknown serverCBDS connectionless broadband data serviceCLNAP connectionless network access protocolCLNIP connectionless network intertace protocolCLNP connectionless network protocolCLS connectionless service/serverCPE customer premises equipmentCRC cyclic redundancy checkDQDB distributed queue dual busDS1 digital signal 1DS3 digital signal 3E1 European transmission level 1E3 European transmission level 3ELAN emulated local area networkESIG European SMDS Interest GroupETSI European Telecommunications Standards InstituteFR frame relayGAA group address agentIEEE Institute of Electrical and Electronics EngineersIP Internet protocolIPX internetwork packet exchangeITU-T International Telecommunications Union- TelecommunicationsIWF interworking functionL3.sub.-- PDU Level 3 protocol data unitLAN local area networkLE.sub.-- ARP LAN emulation address resolution protocolLEC LAN emulation clientLECS LAN emulation configuration serverLES LAN emulation serverLLC logical link controlMAC media access controlOSI open systems interconnectionPDU protocol data unitPHY physical layerSIG SMDS Interest GroupSIP.sub.-- 3 SMDS interface protocol layer 3SMDS switched multi-megabit data serviceSPX sequenced packet exchangeTCP transmission control protocolTP transport protocolUBR unspecified bit rateWAN wide area network______________________________________
The invention is not limited to the particular details of the method depicted and other modifications and applications are contemplated. Certain other changes may be made in the above described method without departing from the true spirit and scope of the invention herein involved. It is intended, therefore, that the subject matter in the above depiction shall be interpreted as illustrative and not in a limiting sense. | Method for the transmission of information packets between a source LEC of a first ELAN and a destination LEC of a second ELAN, having the following method steps: determination of the destination ATM address by transmission of an address resolution request of the source LEC to the second ELAN via a CLS wideare network offering a connectionless service and resolution of the destination MAC address in the second ELAN into the appertaining ATM address; initiation of a connection setup between source LEC and destination LEC via an ATM network ranking higher than the first ELAN and the second ELAN upon employment of the identified destination ATM address; and transmission of the information packets via the higher-ranking ATM network. In one exemplary embodiment, the determined ATM address is transmitted to the first ELAN via the CLS wide-area network as address resolution response and is transmitted thereat to the source LEC, and the source LEC initiates a connection setup to the destination LEC. | 7 |
[0001] This application is related to the apparatus disclosed and claimed in U.S. Pat. No. 6,461,284, issued Oct. 2, 2002 to the same inventor, the contents of which are herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] This invention relates to the field of exercising devices and more particularly to exercise apparatus used to strengthen back muscles, add flexibility to the spine and to increase range of motion.
BACKGROUND OF THE INVENTION
[0003] Back pain is a predominant complaint of patients seen by chiropractors, orthopedic surgeons and other professionals who deal in physical fitness/rehabilitation. The causes of back pain are varied, including injury, congenital defects, and bad habits. For example, individuals with poor posture place excessive pressure on the intervertebral disks and nerves related to the soft tissue of the back.
[0004] An integral part of any rehabilitation of the back and spine, regardless of the cause of the problem, is some form of exercise to strengthen and increase the flexibility of the back. Exercises and exercise equipment should result in movement of the spine to bend forwardly, rearwardly, and from side to side. Bending rearwardly is especially helpful in relieving pressure on the disks.
DESCRIPTION OF THE PRIOR ART
[0005] One method of exercise that is well known employs a large ball, sometimes called a Fit Ball, that is placed between a user's back and a vertical surface, such as a wall. The user assumes a squat position and pushes against the ball with his legs and back. The exercise requires the individual to apply sufficient pressure to prevent the ball from dropping through the application of pressure, while using their legs to move the ball for receipt of the exercise effect. Should the ball fall or otherwise lose contact, the individual could injure themself if their physical ailment was of a type that would not allow for sudden movements.
[0006] In another embodiment, a larger ball may be used on the floor or the like horizontal surface. As the ball rolls about the surface, the user maintains contact by flexing muscles and the skeleton. In this embodiment, the individual may sit on the ball wherein muscle exercise maintains the individual in an upright position providing spine movement and associated flex movement. The ability for an individual to maintain a position on the ball depends on their balance since the curvature of the ball requires balance at the base and apex of where the individual is situated. If an individual employs the ball to work the back, movement of the ball is necessary. However, excess movement may cause the individual to fall off the ball defeating any beneficial effects.
[0007] If the individual has certain physical handicaps, the current ball exercise device could not occur without the assistance of support personnel. This makes the use of current ball technology limited to those persons who have the assistance of support personnel or risk injury to themselves while attempting a rehabilitation.
[0008] U.S. Pat. No. 6,231,489 B1 discloses a back exercise machine which has a base for support of the machine. Attached to the base is an array of parallel rollers upon which the user rests the back in the supine position. The rollers terminate adjacent to a seat and extending from the seat, opposite from the rollers, is a bar for securing the user's feet. The user may sit in the seat and place his feet on the bar, bending rearwardly to allow the rollers to engage his back. This motion decompresses the spinal disks.
[0009] U.S. Pat. No. 4,191,178 discloses the use of a sphere or ball to massage the feet. The ball has a circumference of approximately 15 to 20 inches with protuberances to engage the feet.
[0010] U.S. Pat. No. 5,728,031 discloses an abdominal exerciser employing a vertical frame extending from a base mounted on the floor. Within the frame, is a pivotally mounted sphere that impacts the abdomen when the upper portion of the frame is pushed away from the user.
[0011] There is a Power Ball Bench with Ab Bar, distributed by Sports & Leisure Technology Corp. of Yonkers, N.Y., that has a metal frame with a circular mouth holding a large ball. The user pushes against the ball during exercise. The frame includes other attachments used for various exercises.
[0012] Thus, what is needed is an exercise apparatus that reacts with universal motion when forcibly contacted by an individual requiring equal and opposite body movements in all axes to maintain the point of contact.
SUMMARY OF THE INVENTION
[0013] The exercise apparatus develops flexibility and strength in the back and other portions of the body. The apparatus employs a frame that captures an exercise ball for support of the user's body during exercises. The ball is mounted in a receptacle with a substantial portion of the sphere exposed for contact with the user's body. The sphere has universal movement in the receptacle or may remain in a fixed position. In use, the user sits or lies on the ball with their body in contact with the exposed sphere with feet on the floor or a foot rest. The body is exercised by maintaining a point of contact between the ball and the user's back, sides or stomach.
[0014] Accordingly, it is an objective of the instant invention to teach an exercise device having a captured ball housed within a receptacle or cage. The ball provides a re-active surface to the movement of weight placed on its circumference, either by deformation or by rotation or both.
[0015] Still another objective of the instant invention is to provide an exercise apparatus having a primary purpose of increasing flexibility and strength in the back and spine of a person whose motion is limited by injury, surgery, congenital defects or lack of conditioning.
[0016] It is a further objective of the instant invention to teach universal movement of the captured ball in response to physical movement of an exerciser in contact with the exposed portion of the sphere.
[0017] It is yet another objective of the instant invention to teach a receptacle or cage with an open mouth housing the ball with a portion of the ball exposed for contact by an exerciser.
[0018] It is a still further objective of the invention to teach a frame supporting the cage and attachments to the frame with implements used by an exerciser to translate physical force to the ball for universal motion or deformation.
[0019] Another objective of the invention is to disclose a frame having hand and/or foot supports that allow an individual to maintain a position on the captured ball without assistance from other individuals.
[0020] Still another objective of the instant invention is to provide an exercise apparatus having a fully adjustable attachment for engaging the legs and feet.
[0021] Another objective of the instant invention is to provide an exercise apparatus having attachments for a resistance band attachment.
[0022] Another objective of the instant invention is to provide an exercise apparatus having attachments for engaging the hands.
[0023] Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
[0024] FIG. 1 is a perspective of one embodiment of the invention;
[0025] FIG. 2 is a perspective of the frame of the embodiment depicted in FIG. 1 ;
[0026] FIG. 3 is a perspective the foot rest of FIG. 1 ;
[0027] FIG. 4 is a perspective of a height adjuster of FIG. 1 ; and
[0028] FIG. 5 is a perspective of a manual motor for connection to the embodiment of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0029] The exercise device 10 has a primary purpose of increasing flexibility and strength in the back and spine of a person whose motion is limited by injury, surgery, congenital defects or lack of conditioning. While the use of the device focuses on the back, the device may be used to exercise other parts of the body. Indeed, proper use of the device obviously requires coordinated action from other parts of the body.
[0030] The basic apparatus is shown in FIG. 1 . A large ball or sphere 1 , approximately 2 foot diameter, is captured in a frame 11 having a cage 19 which may be formed of a tubular shape to interact with the surface of the ball. The ball 1 may be a hollow sphere filled with a gas, fluid or it may be solid. The spherical outside wall may be smooth or roughened for better purchase. The sphere 1 is preferably resiliently deformable but will not lose it's shape when supporting the weight of an exerciser.
[0031] The frame 11 supports the sphere on an exercise surface, such as a floor. The cage or receptacle 19 has an open mouth which is sized to accept the circumference of the ball 1 and can capture the ball 1 in a fixed position. Alternatively the cage 19 can allow the ball 1 universal rotation or surface deformation of the ball within the cage. The open mouth of the cage 19 is a circular frame member. The cage 19 is held in spatial relationship by vertical members such as those depicted by numerals 15 , 16 , 17 and 18 . The vertical members 15 and 16 extend from the cage 19 to the radial frame member 14 . The vertical frame members 17 and 18 extend from the cage 19 to the floor or other supporting surface. The circular frame support surface is reinforced by radial frame member 14 . Radial frame member 14 is connected to the attachment 12 at one end and the attachment 13 at the other end. The connections between radial frame member 14 and the attachments 12 and 13 is adjustable so as to accommodate the size of an individual using the ball 1 .
[0032] The attachment 12 has a base 22 which slidably connects with the radial frame member 14 by an adjustable coupling 21 and an aperture 23 . There is a plurality of apertures in base 22 . A stabilizing bar 24 extends laterally from the base 22 to prevent twisting of the base 22 and to support the head rest 32 . The stabilizing bar 24 has rotatable height adjusters 35 at each end.
[0033] The base 22 and the stabilizing bar 24 have a bracket 33 mounted thereon to removably receive a post 25 secured by a pin 34 . The post 25 slidably receives a handle bar support 27 carrying a laterally extending handlebar 28 . The height of the handle bar may be adjusted by pin 26 . Above handlebar support 27 , there is another slidably received head rest post 30 which is height adjustable through the pin 29 . The head rest post 30 has a handle bar 31 extending laterally directly under the head rest 32 . The handle bars 28 and 31 provide an area for an individual to grasp for support while situated on the ball 1 in a prone, supine or sitting position.
[0034] The radial frame 14 extends beyond the circular frame cage 19 and slidably connects with attachment 13 which terminates in a T bar 36 . The extension 13 may be formed in telescoping parts for longitudinal adjustment by pin 20 and aperture 37 . The T bar 36 has a journal 38 which receives a support post 39 . The journal 38 affords an angular adjustment for the support post 38 to permit the user's feet to comfortably engage the foot rest 40 in different exercises and for users of differing heights. The support post 39 includes apertures for adjustment of the foot rest shaft 40 , in length, by coupling pin 41 . The foot rest 42 has a non-slip surface for engaging the feet or footwear of the user. A strap 43 is attached to the foot rest 42 by a swivel 44 and buckles mounted on the edges of the foot rest. The strap 43 is used to anchor the feet to the foot rest during some exercises.
[0035] The stabilizing bar 24 and the T bar 36 each have a pair of rings attached on either side of the longitudinal center line of the frame. These rings 50 are used to connect to one end of resistance bands or tethers 51 . The bands may be elastic or not depending on the exercise to be accomplished. The bands may have a hand grip/foot grip or loop at the free end. While using the exercise device, a user can place one or both hands or feet in the grip or loop portion of the flexible tether, which remains attached at an opposite end thereof to said stabilizing bar. The tether is constructed and arranged to be adjustable in length, and the grip provides manual support for a user in all axes. The bands may be used in conjunction with the ball or by themselves.
[0036] The frame 11 , as shown in FIG. 2 , has poles 52 and 53 extending from the vertical members 17 and 18 , respectively, to a level to be grasped by a user whose body is in contact with the ball. The poles may have hand grips 53 and 54 . Each pole is removably mounted on the vertical member through a journal 55 .
[0037] In FIG. 3 , the foot rest 42 is shown with the strap 43 in the vertical position. Two sets of buckles 56 and 57 are attached to the edges of the foot rest 42 . The ends of the strap are passed through the opposite buckles 57 and doubled back so that they may be removably fastened to the strap by Velcro components 58 and 59 . Another pair of opposite buckles 56 are used to orient the strap in a horizontal position. The strap may be tightened to hold the feet on the foot rest during exercises. The strap may be held in place by the buckles, the Velcro or both.
[0038] In FIG. 4 , the rotatable eccentric adjuster 35 is mounted on the ends of the T bar 36 and stabilizing bar 24 . The adjuster has a plurality of planar surfaces 60 to establish a stable foundation. The planar surface may be changed and the height of the frame attachments may be changed to accommodate an uneven supporting surface while maintaining the exercise device level.
[0039] The manual motor 70 , shown in FIG. 5 , has frame 71 which has one end 72 for removable connection to journal 38 . Mounted on the frame 71 is a chain drive 73 driven by a sprocket wheel 74 and foot pedals 75 . The chain is connected to drive wheel 76 whereby the drive wheel is rotated by the movement of the foot pedals. A friction wheel 77 is in rotary contact with the drive wheel 76 . The friction wheel is adjustable by knob 78 to increase or decrease the amount of force applied to the drive wheel which results in a requirement for more or less force on the pedals 75 .
[0040] As the sphere deforms and/or rotates, the exerciser must apply muscular force to compensate for the shifting location of the point of contact between the body and the ball to avoid dislodgement. Since there is no limit to the direction of deformation or rotation, the exerciser must move in all axes. Further, the device can be used by an individual for sitting on wherein balancing, with or without the wall support, provides the desired flex exercise.
[0041] It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement of parts herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and drawings. | An exercise apparatus for developing flexibility and strength in the back uses a captured ball to support the user's body. The ball is mounted in a receptacle with a substantial portion of the sphere exposed for contact with the user's body. The sphere has universal movement in the receptacle. In use, the user sits or lies on the ball in contact with the exposed sphere and their feet on the floor or a foot rest. The body is exercised by maintaining a point of contact between the ball and the user's back. | 0 |
FIELD OF INVENTION
The present invention relates generally to automatic drip electric coffee makers, but it is to be understood that certain major features of the hereinafter disclosed embodiment of the invention have broader utility and application to hot beverages other than coffee.
SUMMARY OF INVENTION
Many advantages can be obtained from a heating unit for an automatic drip coffee maker which has a practical, economical and effective design to confine steam during the heating process. Confining steam during the heating process not only limits heat loss but also prevents steam from leaking into other parts of the coffee maker and recondensing. The heating system operation is also quieter.
A purpose of the present invention is to provide a structure which is practical, economical and effective in confining steam. Other purposes, objects and advantages of the present invention are described in more detail herein.
Electric automatic water heating apparatus of the present invention is provided with a sealed heating chamber to confine steam generated during heating. In the preferred form, a sealed chamber is formed from a heater casting containing an embedded heating element or resistance rod-type heater. A thermally conductive cover member is sealed to the heater casting with a resilient seal therebetween. The cover and the heater casting form a sealed heating chamber, and steam is confined thereto during the heating process as described in more detail hereinafter.
The cover member also serves as a support for a bimetallic member which controls the flow of water from a reservoir into the sealed heating chamber.
The sealed heating chamber is also positioned or otherwise sealed in the surrounding coffee brewer housing so as to further prevent any leakage of the steam into other parts of the coffee maker. For example, the outlet from the sealed heating chamber into a coffee basket is surrounded by a resilient seal between the outlet and a portion of the coffee brewer housing.
BRIEF DESCRIPTION OF DRAWINGS
Other purposes, objects and advantages will appear from the following description of a preferred embodiment in the drawings wherein:
FIG. 1 is a vertical section taken generally centrally and longitudinally through the coffee brewing machine embodying the present invention;
FIG. 2 is an enlarged sectional view of the sealed heating unit depicted in FIG. 1;
FIG. 3 is an enlarged plan view of the interior portion of the heater casting generally taken along line 3--3 of FIG. 2;
FIG. 4 is an enlarged plan view of the lower surface of the cover portion generally taken along line 4--4 of FIG. 2;
FIG. 5 is an enlarged sectional view of the circled portion in FIG. 2 marked with the numeral 5;
FIG. 6 is an enlarged sectional view of the circled portion in FIG. 2 marked with the numeral 6;
FIG. 7 is a bottom plan view of a clamp biasing the heater casting toward a reservoir and cover member;
FIG. 8 is an enlarged sectional view of the circled portion in FIG. 2 marked with the numeral 8; and
FIG. 9 is a bottom plan view of the heater casting showing the exterior electrical elements of the coffee brewer;
FIG. 10 is an enlarged sectional view of the sealed heating unit depicted in FIG. 1 modified to employ two bimetallic members;
FIG. 11 is an enlarged fragmentary sectional view of the second bimetal 60 depicted in FIG. 10; and
FIG. 12 is a view similar to FIG. 4 but showing the embodiment having two bimetallic members.
INCORPORATION BY REFERENCE
The description of U.S. Pat. No. 4,000,396 is hereby incorporated by reference herein.
DESCRIPTION OF PREFERRED EMBODIMENT
General Arrangement
The preferred embodiment herein will be described with reference to an automatic drip coffee maker, but as noted above, certain major features hereof have broader utility and application for other beverages.
The particular embodiment of the electric automatic water heating apparatus or coffee brewer 10 of the present invention appearing in FIG. 1 comprises, a housing 12 which has three major components: a hood element 14, a column support 16 and a pedestal element 18. The column support 16 is integrally connected to the pedestal element 18 and the hood portion 14. The pedestal element 18 serves as a support for the coffee brewer 10 and contains a warming plate 20 upon which is depicted a coffee carafe. Surrounding the warming plate 20 is a raised lip 22 which is intended to prevent the carafe from sliding off of the warming plate 20.
The hood portion 14 of the coffee brewer 10 contains, as major components, a water reservoir 24, a sealed heating chamber generally designated as 26, and various electrical components. The sealed heating chamber 26 will be described in more detail hereinafter. Water is added to reservoir 24 through a grate 25 in the upper surface of the coffee brewer. The hood portion 14 contains a housing portion 28 having electrical components which are exteriorly located from the sealed heating chamber 26.
One purpose of the present invention is to prevent steam from leaking out of the sealed heating chamber 26 and recondensing in the portion 28 of the housing member 12 containing electrical components.
The hood portion 14 also serves to receive and support a slidably insertable coffee basket 30. The coffee basket 30 is of course intended to contain a coffee filter and coffee grounds for brewing coffee.
General Heating System
The general heating system of the present invention will now be described, particularly with reference to FIGS. 2-4. The sealed heating chamber 26 comprises as its major members a thermally conductive heating member 32 and a thermally conductive cover member 34. The cover member is preferably constructed of a metallic material such as aluminum. Cover member 34 is sealed to the thermally conductive heating member 32 by suitable means, preferably by a resilient, thermally resistant seal 36.
Preferably, the thermally conductive heating member 32 is a metallic heater casting. Embedded within the heater casting 32 is a resistance rod-type heater 38. As seen in FIG. 9, the resistance rod-type heater 38 forms a generally horse-shoe shaped ridge around the perimeter of the heater casting 32. The resistant rod-type heater 38 is embedded in a lower portion or well bottom in the heater casting 32, and heat is conducted through the heater casting 32 from the resistance rod-type heater 38 to any water present in the sealed heating chamber 26.
As seen particularly in FIGS. 2-3, the sealed heating chamber 26 provides for a generally horizontal flow path for the water from inlet or opening 40 to outlet 42. The outlet 42 is horizontally offset from the inlet 40 to provide the generally horizontal flow path of the water from the reservoir 24.
The thermally conductive cover member 34 forms a portion of the bottom surface 46 of the reservoir 24. The reservoir and many components of the housing 12 are made from a thermally nonconductive material, such as plastic, e.g., polypropylene. The cover member 34 has an opening 40 through which any water in reservoir 24 is designed to flow into the sealed heating chamber 26. The thermally conductive cover, preferably of metal, is in thermal contact on one side with the cool reservoir water and on the other side with the sealed heating chamber 26. Thus, the cover member 34 helps transfer a significant amount of heat to the cool reservoir water to preheat it before entering the sealed chamber 26 and also helps recondense steam within the sealed heating chamber 26 due to the relative coolness of the reservoir water.
Surrounding the outlet 42 is a generally vertically upstanding standpipe 48 which serves to establish a water level within the sealed heating chamber 26. Between the inlet 40 and the outlet 42 of the sealed heating chamber is an additional deflecting barrier 50 which is designed to further deflect the generally horizontally flowing water from the inlet to the outlet to ensure sufficient transient time in the sealed heating chamber for proper heating. The deflecting barrier 50 is generally U-shaped, having legs which surround a portion of the standpipe 48. Preferably, one section of the standpipe 48 has a higher wall section 52 oppositely facing the additional barrier 50. Standpipe 48 and the additional water deflecting barrier 50 help reduce any "overshoot" of water from the inlet to the outlet. The heater casting 32 is also provided with a small additional drain hole 54 which is designed to drain the heater casting dry at the end of an operating cycle. A slightly rounded and raised portion 56 on the heater casting 32 is designed to house a thermostat 90 in direct thermal contact therewith for purposes explained in more detail hereinafter.
The underside of cover member 34 is shown in more detail in FIG. 4 wherein certain portions are broken away for clarity. The coffee brewer of the present invention may have one or two bimetallic members 58 and 60. The primary bimetallic member 58 is secured to cover member 34 by suitable means such as rivets 62. The bimetallic member 58 will then be in thermal contact with the cover member 34, the upper portion of which is exposed to any water present in the reservoir 24. The end of the bimetallic member 58 opposite the end fixed by securing means 62 is in contact with a valve member 64, such as a rubber grommet which is embedded and secured to the cover member 34. The primary bimetallic member 58 also may have a small perforation 66 in alignment with the opening 40 for reasons expressed more clearly herein.
If desired, the coffee brewer of the present invention may also have a secondary bimetallic member 60 which is secured to a post 68, which is an integral part of heater casting 32. The secondary bimetallic member 60 has an end sealing against a second valve member 70 containing a smaller opening 72 compared to opening 40 adjacent the primary bimetallic member 58. The bimetallic members 58 and 60 are part of the flow control system of the present invention and will be described more detail in the next section.
Flow Control System
As shown in more detail in FIG. 5, one end of the primary bimetallic member 58 is in sealing engagement, as shown in FIG. 5, with a valve member 64. The valve member 64 in FIG. 5 preferably is a resilient rubber-like grommet which is embedded and secured to thermally conductive cover member 34. Centrally located within the rubber valve member 64 is an opening 40 serving as an outlet for the water from the reservoir 24 into the sealed heater chamber 26.
In one form of the present invention, a small perforation 66 is provided in bimetallic member 58 in alignment with the opening 40. In that form, a coffee brewer having suitable electrical switches is designed to allow a small amount of water to trickle through perforation 66 from the reservoir 24 into the sealed heating chamber 26 shortly after water is poured into reservoir 24. The small amount of water is then heated within the sealed heating chamber, and steam from the heated water contacts the primary bimetallic member 58. In that way, the primary bimetallic member 58 is in both thermal contact with the cool water in the reservoir 24 and also senses the heated steam within the sealed heating chamber 26. Thus, the bimetallic member 58 varies in its deflection from valve member 64 to compensate for the amount of water flowing into the sealed heating chamber and the temperature of the water therein, as described in more detail in U.S. Pat. No. 4,000,396.
Modulation of water flow from the reservoir into the sealed chamber 26 occurs through a balancing of (i) the heat effect from the steam in the sealed chamber 26 on the bimetallic member 58 and (ii) the cooling effect by cool water entering the sealed chamber and by thermal conduction from the cool water in the reservoir through the cover to the bimetallic member 58. The thermally conductive cover 34, preferably of metal, insures cooling of the bimetallic member by thermal conduction, and also transfers heat from the sealed chamber 26 to the water reservoir and helps recondense steam within the chamber 26.
The coffee brewer of the present invention can also be designed to brew coffee at a set period of time in the future, such as by use of a clock. If such a structure is desired, the present invention utilizes both primary and secondary bimetallic members 58, 60. When using both bimetallic members, the primary bimetallic member does not possess any perforations 66, so as to retain water in reservoir 24 until the desired brewing time. The secondary bimetallic member 60 is secured to the casting on post 68 and also has no perforation in its end. In that way, water existing in the reservoir 24 will not leak into the heater casting chamber 26. When power is supplied to the resistance rod heating element 38, such as by a clock, heat is conducted through the mounting post 68 to the secondary bimetallic member 60. The heating up of the secondary bimetallic member 60 causes it to deflect and allow an initial flow of water through opening 72 and past valve member 70. This small trickle of water corresponds to that described above which passes through perforation 66. The operation of the primary bimetallic member 58 is then similar to that described above.
The operation of a bimetallic member is described in more detail in U.S. Pat. No. 4,000,396, at column 7, lines 13 to column 8, line 29.
Sealed Heating Chamber
The particular way in which the sealed heating chamber 26 is designed to prevent the escape of steam into other parts of the coffee brewer will now be described.
FIG. 6 shows in more detail the resilient seal 36 between cover member 34 and the heater casting 32. As seen in FIG. 3, the heater casting 32 is completely circular. A circular structure, such as heater casting 32, is much easier to seal effectively than an irregularly shaped object or a rectangularly shaped object. The seal 36 is generally in the form of a parallelogram which is seated at one end in a recess 74 in casting 32. The recess 74 is in the upper end of casting 32. The other end of resilient seal 36 is received in a recess 76 in the underside of the housing section forming the base 46 of the reservoir 24. One side of the resilient seal 36 is in sealing engagement with an upturned flange 77 of the cover member 34. The upturned flange 77 of the cover member 34 engages a raised rim 79 in the housing section formed in the base portion of the reservoir 24, and the cover member 34 is mechanically staked or crimped at 78 to form a mechanical connection thereto.
A clamp plate 80 is shown in FIG. 7; it is secured by fastening means 82 directly to the housing. The clamp 80 biases the heater casting 32 against resilient seal 36 which in turn forms a seal between the cover member 34 and the heater casting 32. In this manner, clamp plate 80 and heater casting 32 are easily removable from the structure for repair, replacement or other purposes as described in more detail hereinafter.
FIG. 8 shows in more detail the lower seal between the outlet 42 of the heater casting 32 and the housing 12. Between a lower extension of the standpipe 48 and a corresponding portion of the housing 12 is a lower seal 84. The lower seal 84 is also a parallelogram similar to upper resilient seal 36. The lower seal 84 prevents the leakage of any steam exiting the outlet 42, as it enters the coffee basket 30, from escaping back up into the area of the housing portion 28 containing electrical components.
The seals 36 and 84 may be constructed of any resilient material which is capable of withstanding sustained service temperatures encountered by automatic drip coffee makers. A preferred material is silicone rubber.
In the preferred embodiment, location of the seal between the heater casting 32 and the cover member 34 and between the heater casting 32 and the lower portion of the water reservoir 24 insures that the polypropylene reservoir tank does not exceed its sustained service temperature. Depending on the material used for the water reservoir, other mechanisms may be used to both support the sealed heating chamber 26 and also assure that no steam escapes the sealed heating chamber 26 without departing from the present invention.
To further insure a good seal between the cover member 34 and the heater casting 32 and to minimize corrosion, the recess 74 of the heater casting 32 can be coated with a polytetrafluoroethylene paint.
Electrical System
The electrical system of the heater casting 32 used in the preferred embodiment of the present invention is depicted in FIG. 9. A thermostat 90 is secured in good thermal contact externally of the heater casting 32 and in a depression formed by the raised portion 56 (FIGS. 2 and 3) in the heater casting 32. Thus, the thermostat is in good thermal contact with the water flowing from the reservoir through outlet 40 so that the thermostat quickly responds to the conditions within the sealed heating unit 26. As described in U.S. Pat. No. 4,000,396, the thermostat 90 is designed to shut off power when an upper temperature is reached, such as in the range of 190°-205° F., and to reset when a lower temperature is reached, such as in the range of 140°-170° F.
Power is provided from the main hook up through leads 92 and 94. The thermostat 90 is in series with the main power leads 92 and 94 leading to the heat resistance rod heater element 38. The electrical heating system of the present invention is protected not only by the thermostat 90 but also by thermal limiters or heat fuses 96 and 98 which are designed to blow if the heater casting attains a temperature above a safe operating temperature. The thermal limiters 96 and 98 are in direct thermal contact with the heater casting 32 and are held in place by integrally cast lugs 100 and 102. The lugs are integral with heater casting 32 and are cast as an integral part thereof so that the thermal limiters 96, 98 have a direct thermal link with the heater casting 32. In contrast, the thermal limiters of U.S. Pat. No. 4,000,396 were screened by an additional thermal barrier in the form of bracket 104, as seen in FIG. 5 of that patent. Bracket 104 also provided a site for possible corrosion which could further reduce any heat transfer.
The thermostat 90 is in series with the main leads 92 and 94. The electrical system is also provided with an additional resistor 104 which is hooked up in series with the main power leads 92, 94, but in parallel with thermostat 90. The suppression resistor 104 is designed to heat the casting 32 by direct thermal contact therewith, and it is held in place by integral lug 106. The suppression resistor heats the casting 32 so that the casting stays above the closing point of the thermostat 90 to prevent recycling of the operation of the coffee brewer.
Operation, Purpose and Advantages
The operation of the general brewing cycle of the present invention, particularly the bimetallic member 58, is similar to that of U.S. Pat. No. 4,000,396 and need not be described in any detail herein.
The sealed heating chamber of the present invention confines steam to the sealed heating chamber 26 and prevents the steam from recondensing into other portions of the apparatus, particularly portions of the housing 28 containing electrical components. Because of the sealed heating chamber 26, the heating unit of the present invention generates less steam than prior art apparatus and reduces the heat loss to the surrounding atmosphere by reason of escaping steam. The thermally conductive cover member 34 helps preheat the reservoir water, cool the bimetallic member for proper modulation, and recondense the steam within the sealed heating chamber.
The use of a heater casting 32 also has several advantages. The heating unit of the present invention is much cheaper than that for example disclosed in U.S. Pat. No. 4,000,396, not only because of the ability to use nonthermally conductive materials for the reservoir (e.g., plastic), but also because the structure of the present invention permits the use of a non-immersion type resistance heating rod 38. Embedment of the heating element 38 within the casting 32 avoids direct water/heating element contact. The heater casting of the present invention also provides better heat transfer to the thermal limiter fuses 96, 98. Better heat transfer provides for a better and more accurate response of the thermal limiter resistors 96, 98. The casting of the present invention is also circular which permits easy sealing to confine the steam. Moreover, the heater casting of the present invention is much quieter than the structure of U.S. Pat. No. 4,000,396.
The sealed heating unit of the present invention also has fewer parts, is easier to assemble and has a more easily removable heating element for repair or replacement.
Unlike the prior art, the present invention also has a structure designed to prevent leakage of steam even from the outlet of the heating chamber into other portions of the housing which may contain electrical components. The design of the present invention also has fewer heat transfer barriers between the resistant rod heater elements and the water compared to some prior art structures without the need for using the more expensive immersion type heaters. The structure of the present invention also reduces the areas for possible corrosion.
Because of the structure of the present invention, the reservoir can be formed of a plastic material which is much cheaper than a metallic material. The reservoir therefore need not be constructed of a material capable of withstanding the high service temperatures within the sealed heating chamber, but instead the reservoir can be insulated therefrom.
The heating system of the present invention also generates a lesser amount of steam than the commercial brewer made under U.S. Pat. No. 4,000,396 and much less steam compared to pump type models which ended up pumping large quantities of generated steam into the brewing cycle. | An electric automatic water heating apparatus for drip type beverage, e.g., coffee makers has a housing provided with a reservoir composed of a material of low thermal conductivity arranged to supply water by gravity to a sealed heating chamber having an inlet communicating with the reservoir and an outlet for discharging heated water for use. The sealed heating chamber includes an open top, cup-shaped, metallic casting having an electric rod-type resistance heating element embedded therein, and a metallic cover member closing the open top of the casting for confining steam generated during heating to the heating chamber. The cover is secured to and forms a bottom surface portion of the reservoir exposed to the water in therein. The cover serves as a support for a bimetallic member which controls the flow of water through the inlet into the heating chamber in response to the temperature in the heating chamber. Seals are provided between the heating chamber and housing for blocking flow of steam or water from the heating chamber into the housing area containing electrical components. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit from U.S. Application No. 60/395,233, filed Jul. 11, 2002, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to the treatment of neoplasms such as cancer.
[0003] Cancer is a disease marked by the uncontrolled growth of abnormal cells. Cancer cells have overcome the barriers imposed in normal cells, which have a finite lifespan, to grow indefinitely. As the growth of cancer cells continue, genetic alterations may persist until the cancerous cell has manifested itself to pursue a more aggressive growth phenotype. If left untreated, metastasis, the spread of cancer cells to distant areas of the body by way of the lymph system or bloodstream, may ensue, destroying healthy tissue.
[0004] The treatment of cancer has been hampered by the fact that there is considerable heterogeneity even within one type of cancer. Some cancers, for example, have the ability to invade tissues and display an aggressive course of growth characterized by metastases. These tumors generally are associated with a poor outcome for the patient. Ultimately, tumor heterogeneity results in the phenomenon of multiple drug resistance, i.e., resistance to a wide range of structurally unrelated cytotoxic anticancer compounds, J. H. Gerlach et al., Cancer Surveys , 5:25-46 (1986). The underlying cause of progressive drug resistance may be due to a small population of drug-resistant cells within the tumor (e.g., mutant cells) at the time of diagnosis, as described, for example, by J. H. Goldie and Andrew J. Coldman, Cancer Research , 44:3643-3653 (1984). Treating such a tumor with a single drug can result in remission, where the tumor shrinks in size as a result of the killing of the predominant drug-sensitive cells. However, with the drug-sensitive cells gone, the remaining drug-resistant cells can continue to multiply and eventually dominate the cell population of the tumor. Therefore, the problems of why metastatic cancers develop pleiotropic resistance to all available therapies, and how this might be countered, are the most pressing in cancer chemotherapy.
[0005] Anticancer therapeutic approaches are needed that are reliable for a wide variety of tumor types, and particularly suitable for invasive tumors. Importantly, the treatment must be effective with minimal host toxicity. In spite of the long history of using multiple drug combinations for the treatment of cancer and, in particular, the treatment of multiple drug resistant cancer, positive results obtained using combination therapy are still frequently unpredictable.
SUMMARY OF THE INVENTION
[0006] The present invention features a combination therapy involving the use of pentamidine, or an analog of pentamidine, and chlorpromazine, or an analog of chlorpromazine. A combination of these two agents has been found to be beneficial in the treatment of neoplasms.
[0007] Accordingly, in a first aspect, the invention features a method for treating a patient having a neoplasm, by administering to the patient a first compound having the formula (I):
[0008] or a pharmaceutically acceptable salt thereof,
[0009] wherein R 2 is selected from the group consisting of: CF 3 , halo, OCH 3 , COCH 3 , CN, OCF 3 , COCH 2 CH 3 , CO(CH 2 ) 2 CH 3 , and SCH 2 CH 3 ;
[0010] R 9 is selected from the group consisting of:
[0011] each of R 1 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 is independently H, OH, F, OCF 3 , or OCH 3 ; and W is selected from the group consisting of:
[0012] and, b) a second compound of formula (II):
[0013] or a pharmaceutically acceptable salt thereof,
[0014] wherein A is
[0015] wherein
[0016] each of X and Y is, independently, O, NR 19 , or S,
[0017] each of R 14 and R 19 is, independently, H or C 1 -C 6 alkyl,
[0018] each of R 15 , R 16 , R 17 , and R 18 is, independently, H, C 1 -C 6 alkyl, halogen,
[0019] C 1 -C 6 alkyloxy, C 6 -C 18 aryloxy, or C 6 -C 18 aryl-C 1 -C 6 alkyloxy,
[0020] p is an integer between 2 and 6, inclusive,
[0021] each of m and n is, independently, an integer between 0 and 2, inclusive,
[0022] each of R 10 and R 11 is
[0023] wherein R 21 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy-C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl, R 22 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, carbo(C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryl C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryloxy), or C 6 -C 18 aryl, and R 20 is H, OH, or C 1 -C 6 alkyloxy, or R 20 and R 21 together represent
[0024] wherein each of R 23 , R 24 , and R 25 is, independently, H, C 1 -C 6 alkyl, halogen, or trifluoromethyl, each of R 26 , R 27 , R 28 , and R 29 is, independently, H or C 1 -C 6 alkyl, and R 30 is H, halogen, trifluoromethyl, OCF 3 , NO 2 , C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl,
[0025] each of R 12 and R 13 is, independently, H, Cl, Br, OH, OCH 3 , OCF 3 , NO 2 , and NH 2 , or R 12 and R 13 together form a single bond.
[0026] The invention also features compositions that include a compound of formula (I) and a compound of formula (II) and a pharmaceutically acceptable carrier.
[0027] Preferably, the compound of formula (I) is acepromazine, chlorfenethazine, cyamemazine, enanthate, fluphenazine, mepazine, methotrimeprazine, methoxypromazine, norchlorpromazine, perazine, perphenazine, prochlorperazine, promethazine, propiomazine, putaperazine, thiethylperazine, thiopropazate, thioridazine, trifluoperazine, or triflupromazine and the compound of formula (II) is pentamidine, propamidine, butamidine, heptamidine, nonamidine, stilbamidine, hydroxystilbamidine, diminazene, dibrompropamidine, 2,5-bis(4-amidinophenyl)furan, 2,5-bis(4-amidinophenyl)furan-bis-O-methylamidoxime, 2,5-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,5-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,4-bis(4-amidinophenyl)furan, 2,4-bis(4-amidinophenyl)furan-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,4-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,5-bis(4-amidinophenyl) thiophene, 2,5-bis(4-amidinophenyl) thiophene-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)thiophene, 2,4-bis(4-amidinophenyl)thiophene-bis-O-methylamidoxime. Most preferably, the compound of formula (I) is chlorpromazine, perphenazine or promethazine and the compound of formula (II) is pentamidine, 2,5-bis(4-amidinophenyl)furan, or 2,5-bis(4-amidinophenyl)furan-bis-O-methylamidoxime.
[0028] In a related aspect, the invention features another method for treating a patient having a neoplasm, by administering to the patient a first compound having the formula (I):
[0029] or a pharmaceutically acceptable salt thereof,
[0030] wherein R 9 has the formula:
[0031] wherein n is 0 or 1, each of R 32 , R 33 , and R 34 is, independently, H or substituted or unsubstituted C 1-6 alkyl, and Z is NR 35 R 36 or OR 37 , wherein each of R 35 and R 36 is, independently, H, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted alkaryl, substituted or unsubstituted alkheteroaryl, and R 37 is H, C 1-6 alkyl, or C 1-7 acyl, wherein any of R 33 , R 34 , R 35 , and R 36 can be optionally taken together with intervening carbon or non-vicinal O, S, or N atoms to form one or more five- to seven-membered rings, substituted with one or more hydrogens, substituted or unsubstituted C 1-6 alkyl groups, C 6-12 aryl groups, alkoxy groups, halogen groups, substituted or unsubstituted alkaryl groups, or substituted or unsubstituted alkheteroaryl groups;
[0032] and, b) a second compound having the formula (II):
[0033] or a pharmaceutically acceptable salt thereof,
[0034] wherein A is
[0035] each of X and Y is independently O or NH;
[0036] p is an integer between 2 and 6, inclusive; and
[0037] m and n are, independently, integers between 0 and 2, inclusive, wherein the sum of m and n is greater than 0;
[0038] or A is
[0039] each of X and Y is independently O or NH,
[0040] each of m and n is 0, and
[0041] each of R 10 and R 11 is, independently, selected from the group represented by
[0042] wherein R 2 is C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl, R 22 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, carbo(C 1 -C 6 alkoxy), carbo(C 6 -C 18 aryl C 1 -C 6 alkoxy), carbo(C 6 -C 18 aryloxy), or C 6 -C 18 aryl, and R 20 is H, OH, or C 1 -C 6 alkyloxy, or R 20 and R 21 together represent
[0043] wherein each of R 23 , R 24 , and R 25 is, independently, H, C 1 -C 6 alkyl, halogen, or trifluoromethyl, each of R 26 , R 27 , and R 28 is, independently, H or C 1 -C 6 alkyl, and R 29 is C 1 -C 6 alkyl, C 1 -C 6 alkyloxy, or trifluoromethyl;
[0044] or A is
[0045] each of X and Y is, independently, O, NR 19 , or S,
[0046] each of R 14 and R 19 is, independently, H or C 1 -C 6 alkyl,
[0047] each of R 15 , R 16 , R 17 , and R 18 is, independently, H, C 1 -C 6 alkyl, halogen,
[0048] C 1 -C 6 alkyloxy, C 6 -C 18 aryloxy, or C 6 -C 18 aryl C 1 -C 6 alkyloxy,
[0049] R 31 is C 1 -C 6 alkyl,
[0050] p is an integer between 2 and 6, inclusive,
[0051] each of m and n is, independently, an integer between 0 and 2, inclusive,
[0052] each of R 10 and R 11 is, independently, selected from the group represented by
[0053] wherein R 21 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl, R 22 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, carbo(C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryl C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryloxy), or C 6 -C 18 aryl, and R 20 is H, OH, or C 1 -C 6 alkyloxy, or R 20 and R 21 together represent
[0054] wherein each of R 23 , R 24 , and R 25 is, independently, H, C 1 -C 6 alkyl, halogen, or trifluoromethyl, each of R 26 , R 27 , R 28 , and R 29 are, independently, H or C 1 -C 6 alkyl, and R 30 is H, halogen, trifluoromethyl, OCF 3 , NO 2 , C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl.
[0055] Preferably, the compound of formula (I) is acepromazine, chlorfenethazine, chlorpromazine, cyamemazine, enanthate, fluphenazine, mepazine, methotrimeprazine, methoxypromazine, norchlorpromazine, perazine, perphenazine, prochlorperazine, promethazine, propiomazine, putaperazine, thiethylperazine, thiopropazate, thioridazine, trifluoperazine, or triflupromazine and the compound of formula (II) is propamidine, butamidine, heptamidine, nonamidine, stilbamidine, hydroxystilbamidine, diminazene, dibrompropamidine, 2,5-bis(4-amidinophenyl)furan, 2,5-bis(4-amidinophenyl)furan-bis-O-methylamidoxime, 2,5-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,5-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,4-bis(4-amidinophenyl)furan, 2,4-bis(4-amidinophenyl)furan-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,4-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,5-bis(4-amidinophenyl) thiophene, 2,5-bis(4-amidinophenyl) thiophene-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)thiophene, 2,4-bis(4-amidinophenyl)thiophene-bis-O-methylamidoxime. Most preferably, the compound of formula (I) is chlorpromazine, perphenazine or promethazine and the compound of formula (II) is pentamidine, 2,5-bis(4-amidinophenyl)furan, or 2,5-bis(4-amidinophenyl)furan-bis-O-methylamidoxime.
[0056] The first and second compounds are administered within 14 days of each other, in amounts sufficient to inhibit the growth of the neoplasm. Preferably, the two compounds are administered within ten days of each other, more preferably within five days of each other, and most preferably within twenty-four hours of each other or even simultaneously.
[0057] In another aspect, the invention features a method for treating a patient having a neoplasm such as cancer. In this method the patient is administered, (a) a first compound selected from prochlorperazine, perphenazine, mepazine, methotrimeprazine, acepromazine, thiopropazate, perazine, propiomazine, putaperazine, thiethylperazine, methopromazine, chlorfenethazine, cyamemazine, perphenazine, norchlorpromazine, trifluoperazine, thioridazine (or a salt of any of the above), and dopamine D2 antagonists (e.g., sulpride, pimozide, spiperone, ethopropazine, clebopride, bupropion, and haloperidol), and, (b) a second compound selected from pentamidine, propamidine, butamidine, heptamidine, nonamidine, stilbamidine, hydroxystilbamidine, diminazene, benzamidine, phenamidine, dibrompropamidine, 1,3-bis(4-amidino-2-methoxyphenoxy)propane, phenamidine, amicarbalide, 1,5-bis(4′-(N-hydroxyamidino)phenoxy)pentane, 1,3-bis(4′-(N-hydroxyamidino)phenoxy)propane, 1,3-bis(2′-methoxy-4′-(N-hydroxyamidino)phenoxy)propane, 1,4-bis(4′-(N-hydroxyamidino)phenoxy)butane, 1,5-bis(4′-(N-hydroxyamidino)phenoxy)pentane, 1,4-bis(4′-(N-hydroxyamidino)phenoxy)butane, 1,3-bis(4′-(4-hydroxyamidino)phenoxy)propane, 1,3-bis(2′-methoxy-4′-(N-hydroxyamidino)phenoxy)propane, 2,5-bis[4-amidinophenyl]furan, 2,5-bis[4-amidinophenyl]furan-bis-amidoxime, 2,5-bis[4-amidinophenyl]furan-bis-O-methylamidoxime, 2,5-bis[4-amidinophenyl]furan-bis-O-ethylamidoxime, 2,5-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,5-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,4-bis(4-amidinophenyl)furan, 2,4-bis(4-amidinophenyl)furan-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,4-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,5-bis(4-amidinophenyl) thiophene, 2,5-bis(4-amidinophenyl) thiophene-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)thiophene, 2,4-bis(4-amidinophenyl)thiophene-bis-O-methylamidoxime, 2,8-diamidinodibenzothiophene, 2,8-bis(N-isopropylamidino)carbazole, 2,8-bis(N-hydroxyamidino)carbazole, 2,8-bis(2-imidazolinyl)dibenzothiophene, 2,8-bis(2-imidazolinyl)-5,5-dioxodibenzothiophene, 3,7-diamidinodibenzothiophene, 3,7-bis(N-isopropylamidino)dibenzothiophene, 3,7-bis(N-hydroxyamidino)dibenzothiophene, 3,7-diaminodibenzothiophene, 3,7-dibromodibenzothiophene, 3,7-dicyanodibenzothiophene, 2,8-diamidinodibenzofuran, 2,8-di(2-imidazolinyl)dibenzofuran, 2,8-di(N-isopropylamidino)dibenzofuran, 2,8-di(N-hydroxylamidino)dibenzofuran, 3,7-di(2-imidazolinyl)dibenzofuran, 3,7-di(isopropylamidino)dibenzofuran, 3,7-di(N-hydroxylamidino)dibenzofuran, 2,8-dicyanodibenzofuran, 4,4′-dibromo-2,2′-dinitrobiphenyl, 2-methoxy-2′-nitro-4,4′-dibromobiphenyl, 2-methoxy-2′-amino-4,4′-dibromobiphenyl, 3,7-dibromodibenzofuran, 3,7-dicyanodibenzofuran, 2,5-bis(5-amidino-2-benzimidazolyl)pyrrole, 2,5-bis[5-(2-imidazolinyl)-2-benzimidazolyl]pyrrole, 2,6-bis[5-(2-imidazolinyl)-2-benzimidazolyl]pyridine, 1-methyl-2,5-bis(5-amidino-2-benzimidazolyl)pyrrole, 1-methyl-2,5-bis[5-(2-imidazolyl)-2-benzimidazolyl]pyrrole, 1-methyl-2,5-bis[5-(1,4,5,6-tetrahydro-2-pyrimidinyl)-2-benzimidazolyl]pyrrole, 2,6-bis(5-amidino-2-benzimidazoyl)pyridine, 2,6-bis[5-(1,4,5,6-tetrahydro-2-pyrimidinyl)-2-benzimidazolyl]pyridine, 2,5-bis(5-amidino-2-benzimidazolyl)furan, 2,5-bis-[5-(2-imidazolinyl)-2-benzimidazolyl]furan, 2,5-bis-(5-N-isopropylamidino-2-benzimidazolyl)furan, 2,5-bis-(4-guanylphenyl)furan, 2,5-bis(4-guanylphenyl)-3,4-dimethylfuran, 2,5-bis {p-[2-(3,4,5,6-tetrahydropyrimidyl)phenyl]}furan, 2,5-bis[4-(2-imidazolinyl)phenyl]furan, 2,5[bis-{4-(2-tetrahydropyrimidinyl)}phenyl]-3-(p-tolyloxy)furan, 2,5[bis{4-(2-imidazolinyl)}phenyl]-3-(p-tolyloxy)furan, 2,5-bis{4-[5-(N-2-aminoethylamido)benzimidazol-2-yl]phenyl}furan, 2,5-bis[4-(3a,4,5,6,7,7a-hexahydro-1H-benzimidazol-2-yl)phenyl]furan, 2,5-bis[4-(4,5,6,7-tetrahydro-1H-1,3-diazepin-2-yl)phenyl]furan, 2,5-bis(4-N,N-dimethylcarboxhydrazidephenyl)furan, 2,5-bis {4-[2-(N-2-hydroxyethyl)imidazolinyl]phenyl}furan, 2,5-bis[4-(N-isopropylamidino)phenyl]furan, 2,5-bis{4-[3-(dimethylaminopropyl)amidino]phenyl}furan, 2,5-bis {4-[N-(3-aminopropyl)amidino]phenyl}furan, 2,5-bis[2-(imidzaolinyl)phenyl]-3,4-bis(methoxymethyl)furan, 2,5-bis[4-N-(dimethylaminoethyl)guanyl]phenylfuran, 2,5-bis{4-[(N-2-hydroxyethyl)guanyl]phenyl}furan, 2,5-bis[4-N-(cyclopropylguanyl)phenyl]furan, 2,5-bis[4-(N,N-diethylaminopropyl)guanyl]phenylfuran, 2,5-bis{4-[2-(N-ethylimidazolinyl)]phenyl}furan, 2,5-bis{4-[N-(3-pentylguanyl)]}phenylfuran, 2,5-bis[4-(2-imidazolinyl)phenyl]-3-methoxyfuran, 2,5-bis[4-(N-isopropylamidino)phenyl]-3-methylfuran, bis[5-amidino-2-benzimidazolyl]methane, bis[5-(2-imidazolyl)-2-benzimidazolyl]methane, 1,2-bis[5-amidino-2-benzimidazolyl]ethane, 1,2-bis[5-(2-imidazolyl)-2-benzimidazolyl]ethane, 1,3-bis[5-amidino-2-benzimidazolyl]propane, 1,3-bis[5-(2-imidazolyl)-2-benzimidazolyl]propane, 1,4-bis[5-amidino-2-benzimidazolyl]propane, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]butane, 1,8-bis[5-amidino-2-benzimidazolyl]octane, trans-1,2-bis[5-amidino-2-benzimidazolyl]ethene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1-methylbutane, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2-ethylbutane, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1-methyl-1-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2,3-diethyl-2-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1,3-butadiene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2-methyl-1,3-butadiene, bis[5-(2-pyrimidyl)-2-benzimidazolyl]methane, 1,2-bis[5-(2-pyrimidyl)-2-benzimidazolyl]ethane, 1,3-bis[5-amidino-2-benzimidazolyl]propane, 1,3-bis[5-(2-pyrimidyl)-2-benzimidazolyl]propane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]butane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1-methylbutane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2-ethylbutane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1-methyl-1-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2,3-diethyl-2-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1,3-butadiene, and 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2-methyl-1,3-butadiene, 2,4-bis(4-guanylphenyl)pyrimidine, 2,4-bis(4-imidazolin-2-yl)pyrimidine, 2,4-bis[(tetrahydropyrimidinyl-2-yl)phenyl]pyrimidine, 2-(4-[N-i-propylguanyl]phenyl)-4-(2-methoxy-4-[N-i-propylguanyl]phenyl)pyrimidine, 4-(N-cyclopentylamidino)-1,2-phenylene diamine, 2,5-bis-[2-(5-amidino)benzimidazoyl]furan, 2,5-bis[2-{5-(2-imidazolino)}benzimidazoyl]furan, 2,5-bis[2-(5-N-isopropylamidino)benzimidazoyl]furan, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]furan, 2,5-bis[2-(5-amidino)benzimidazoyl]pyrrole, 2,5-bis[2-{5-(2-imidazolino)}benzimidazoyl]pyrrole, 2,5-bis[2-(5-N-isopropylamidino)benzimidazoyl]pyrrole, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]pyrrole, 1-methyl-2,5-bis[2-(5-amidino)benzimidazoyl]pyrrole, 2,5-bis[2-{5-(2-imidazolino)}benzimidazoyl]-1-methylpyrrole, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]-1-methylpyrrole, 2,5-bis[2-(5-N-isopropylamidino)benzimidazoyl]thiophene, 2,6-bis[2-{5-(2-imidazolino)}benzimidazoyl]pyridine, 2,6-bis[2-(5-amidino)benzimidazoyl]pyridine, 4,4′-bis[2-(5-N-isopropylamidino)benzimidazoyl]-1,2-diphenylethane, 4,4′-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]-2,5-diphenylfuran, 2,5-bis[2-(5-amidino)benzimidazoyl]benzo[b]furan, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]benzo[b]furan, 2,7-bis[2-(5-N-isopropylamidino)benzimidazoyl]fluorine, 2,5-bis[4-(3-(N-morpholinopropyl)carbamoyl)phenyl]furan, 2,5-bis[4-(2-N,N-dimethylaminoethylcarbamoyl)phenyl]furan, 2,5-bis[4-(3-N,N-dimethylaminopropylcarbamoyl)phenyl]furan, 2,5-bis[4-(3-N-methyl-3-N-phenylaminopropylcarbamoyl)phenyl]furan, 2,5-bis[4-(3-N,N 8 ,N 11 -trimethylaminopropylcarbamoyl)phenyl]furan, 2,5-bis[3-amidinophenyl]furan, 2,5-bis[3-(N-isopropylamidino)amidinophenyl]furan, 2,5-bis[3[(N-(2-dimethylaminoethyl)amidino]phenylfuran, 2,5-bis[4-(N-2,2,2-trichloroethoxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-thioethylcarbonyl) amidinophenyl]furan, 2,5-bis[4-(N-benzyloxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-phenoxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-(4-fluoro)-phenoxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-(4-methoxy)phenoxycarbonyl)amidinophenyl]furan, 2,5-bis[4(1-acetoxyethoxycarbonyl)amidinophenyl]furan, and 2,5-bis[4-(N-(3-fluoro)phenoxycarbonyl)amidinophenyl]furan, or a salt of any of the above.
[0058] Alternatively, the second compound can be a functional analog of pentamidine, such as netropsin, distamycin, bleomycin, actinomycin, daunorubicin, or a compound that falls within a formula provided in any of U.S. Pat. Nos. 5,428,051; 5,521,189; 5,602,172; 5,643,935; 5,723,495; 5,843,980; 6,008,247; 6,025,398; 6,172,104; 6,214,883; and 6,326,395, or U.S. patent application Ser. Nos. US 2001/0044468 A1 and US 2002/0019437 A1.
[0059] The methods of the invention can include administration to a patient a compound of formula (I) and a compound of formula (II) by intravenous, intramuscular, inhalation, rectal, or oral administration.
[0060] In another aspect, the invention features a method for treating a patient having a neoplasm such as cancer by the method of either the first or second aspect that further includes administration to the patient an additional treatment for cancer, with the additional treatment and the treatment of the first or second aspect administered within six months of each other. The additional treatment can be surgery, radiation therapy, chemotherapy, immunotherapy, anti-angiogenesis. therapy, or gene therapy. Preferably, the additional treatment is chemotherapy with an antiproliferative agent. Most preferably, the additional treatment includes administering to a patient a Group A anti-proliferative agent, as defined below. Preferred agents include bleomycin, carmustine, cisplatin, daunorubicin, etoposide, melphalan, mercaptopurine, methotrexate, mitomycin, vinblastine, paclitaxel, docetaxel, vincristine, vinorelbine, cyclophosphamide, chlorambucil, gemcitabine, capecitabine, 5-fluorouracil, fludarabine, raltitrexed, irinotecan, topotecan, doxorubicin, epirubicin, letrozole, anastrazole, formestane, exemestane, tamoxifen, toremofine, goserelin, leuporelin, bicalutamide, flutamide, nilutamide, hypericin, trastuzumab, or rituximab, or any combination thereof.
[0061] When the additional treatment is a chemotherapy, it and a compound of formulas (I) and a compound of formula (II) can be administered within 14 days of each other. Preferably, all treatments of the third aspect are administered within ten days of each other, more preferably within five days of each other, and most preferably within twenty-four hours of each other or even simultaneously.
[0062] Cancers treated according to any of the methods of the invention can be, for example, leukemias (e.g., acute leukemia, acute lymphocytic leukemia, acute myelocytic leukemia, acute myeloblastic leukemia, acute promyelocytic leukemia, acute myelomonocytic leukemia, acute monocytic leukemia, acute erythroleukemia, chronic leukemia, chronic myelocytic leukemia, chronic lymphocytic leukemia), polycythemia vera, lymphoma (Hodgkin's disease, non-Hodgkin's disease), Waldenstrom's macroglobulinemia, heavy chain disease, and solid tumors such as sarcomas and carcinomas (e.g., fibrosarcoma, myxosarcoma, liposarcoma, chondrosarcoma, osteogenic sarcoma, chordoma, angiosarcoma, endotheliosarcoma, lymphangiosarcoma, lymphangioendotheliosarcoma, synovioma, mesothelioma, Ewing's tumor, leiomyosarcoma, rhabdomyosarcoma, colon carcinoma, pancreatic cancer, breast cancer, ovarian cancer, prostate cancer, squamous cell carcinoma, basal cell carcinoma, adenocarcinoma, sweat gland carcinoma, sebaceous gland carcinoma, papillary carcinoma, papillary adenocarcinomas, cystadenocarcinoma, medullary carcinoma, bronchogenic carcinoma, renal cell carcinoma, hepatoma, bile duct carcinoma, choriocarcinoma, seminoma, embryonal carcinoma, Wilm's tumor, cervical cancer, uterine cancer, testicular cancer, lung carcinoma, small cell lung carcinoma, bladder carcinoma, epithelial carcinoma, glioma, astrocytoma, medulloblastoma, craniopharyngioma, ependymoma, pinealoma, hemangioblastoma, acoustic neuroma, oligodendroglioma, schwannoma, meningioma, melanoma, neuroblastoma, and retinoblastoma. Preferably, the cancer being treated is lung cancer, especially lung cancer attributed to squamous cell carcinoma, adenocarinoma, or large cell carcinoma, colorectal cancer, ovarian cancer, especially ovarian adenocarcinoma, or prostate cancer.
[0063] In another aspect, the invention features a method for treating a patient who has a neoplasm, or inhibiting the development of a neoplasm in a patient who is at risk for developing a neoplasm by administering to the patient a pharmaceutical composition that includes a compound of formula (I), a compound of formula (II), and a pharmaceutically acceptable carrier.
[0064] In one embodiment, the compound of formula (II) is
[0065] or a pharmaceutically acceptable salt thereof,
[0066] wherein A is
[0067] each of X and Y is independently O or NH;
[0068] p is an integer between 2 and 6, inclusive; and
[0069] m and n are, independently, integers between 0 and 2, inclusive, wherein the sum of m and n is greater than 0;
[0070] or A is
[0071] each of X and Y is independently O or NH,
[0072] each of m and n is 0, and
[0073] each of R 10 and R 11 is, independently, selected from the group represented by
[0074] wherein R 21 is C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl, R 22 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, carbo(C 1 -C 6 alkoxy), carbo(C 6 -C 18 aryl C 1 -C 6 alkoxy), carbo(C 6 -C 18 aryloxy), or C 6 -C 18 aryl, and R 20 is H, OH, or C 1 -C 6 alkyloxy, or R 20 and R 21 together represent
[0075] wherein each of R 23 , R 24 , and R 25 is, independently, H, C 1 -C 6 alkyl, halogen, or trifluoromethyl, each of R 26 , R 27 , and R 28 is, independently, H or C 1 -C 6 alkyl, and R 29 is C 1 -C 6 alkyl, C 1 -C 6 alkyloxy, or trifluoromethyl;
[0076] or A is
[0077] each of X and Y is, independently, O, NR 19 , or S,
[0078] each of R 14 and R 19 is, independently, H or C 1 -C 6 alkyl,
[0079] each of R 15 , R 16 , R 17 , and R 18 is, independently, H, C 1 -C 6 alkyl, halogen,
[0080] C 1 -C 6 alkyloxy, C 6 -C 18 aryloxy, or C 6 -C 18 aryl C 1 -C 6 alkyloxy,
[0081] R 31 is C 1 -C 6 alkyl,
[0082] p is an integer between 2 and 6, inclusive,
[0083] each of m and n is, independently, an integer between 0 and 2, inclusive,
[0084] each of R 10 and R 11 is, independently, selected from the group represented by
[0085] wherein R 21 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl, R 22 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, carbo(C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryl C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryloxy), or C 6 -C 18 aryl, and R 20 is H, OH, or C 1 -C 6 alkyloxy, or R 20 and R 21 together represent
[0086] wherein each of R 23 , R 24 , and R 25 is, independently, H, C 1 -C 6 alkyl, halogen, or trifluoromethyl, each of R 26 , R 27 , R 28 , and R 29 are, independently, H or C 1 -C 6 alkyl, and R 30 is H, halogen, trifluoromethyl, OCF 3 , NO 2 , C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl..
[0087] Methods of the invention can include administration to a patient a compound of formula (I) and a compound of formula (II) by intravenous, intramuscular, inhalation, rectal, or oral administration. These compounds are present in amounts that, when administered together to a patient having a neoplasm, reduce cell proliferation in the neoplasm.
[0088] In another aspect, the invention features a method for treating a patient who has a neoplasm, or inhibiting the development of a neoplasm in a patient who is at risk for developing a neoplasm. The method includes administration to a patient an inhibitor of protein kinase C and a compound of formula (II). In one embodiment, this method can further include administering to the patient one or more Group A antiproliferative agents.
[0089] In another aspect, the invention features a method for treating a patient who has a neoplasm, or inhibiting the development of a neoplasm in a patient who is at risk for developing a neoplasm. The method includes administration to a patient a compound of formula (I) and an endo-exonuclease inhibitor. In one embodiment, this method can further include administering to the patient one or more Group A antiproliferative agents.
[0090] In yet another aspect, the invention features a method for treating a patient who has a neoplasm, or inhibiting the development of a neoplasm in a patient who is at risk for developing a neoplasm. The method includes administration to a patient a compound of formula (I) and a PRL phosphatase inhibitor or a PTP1B inhibitor. In one embodiment, this method can further include administering to the patient one or more Group A antiproliferative agents.
[0091] In the combination therapies of the invention, the therapy components are administered simultaneously, or within 14 days of each other, in amounts sufficient to inhibit the growth of said neoplasm.
[0092] Combination therapy may be provided wherever chemotherapy is performed: at home, the doctor's office, a clinic, a hospital's outpatient department, or a hospital. Treatment generally begins at a hospital so that the doctor can observe the therapy's effects closely and make any adjustments that are needed. The duration of the combination therapy depends on the kind of cancer being treated, the age and condition of the patient, the stage and type of the patient's disease, and how the patient's body responds to the treatment. Drug administration may be performed at different intervals (e.g., daily, weekly, or monthly) and the administration of each agent can be determined individually. Combination therapy may be given in on-and-off cycles that include rest periods so that the patient's body has a chance to build healthy new cells and regain its strength.
[0093] Depending on the type of cancer and its stage of development, the combination therapy can be used to treat cancer, to slow the spreading of the cancer, to slow the cancer's growth, to kill or arrest cancer cells that may have spread to other parts of the body from the original tumor, to relieve symptoms caused by the cancer, or to prevent cancer in the first place. Combination therapy can also help people live more comfortably by eliminating cancer cells that cause pain or discomfort.
[0094] The administration of a combination of the present invention allows for the administration of lower doses of each compound, providing similar efficacy and lower toxicity compared to administration of either compound alone. Alternatively, such combinations result in improved efficacy in treating neoplasms with similar or reduced toxicity.
[0095] As used herein, the terms “cancer” or “neoplasm” or “neoplastic cells” is meant a collection of cells multiplying in an abnormal manner. Cancer growth is uncontrolled and progressive, and occurs under conditions that would not elicit, or would cause cessation of, multiplication of normal cells.
[0096] By “inhibits the growth of a neoplasm” is meant measurably slows, stops, or reverses the growth rate of the neoplasm or neoplastic cells in vitro or in vivo. Desirably, a slowing of the growth rate is by at least 20%, 30%, 50%, or even 70%, as determined using a suitable assay for determination of cell growth rates (e.g., a cell growth assay described herein). Typically, a reversal of growth rate is accomplished by initiating or accelerating necrotic or apoptotic mechanisms of cell death in the neoplastic cells, resulting in a shrinkage of the neoplasm.
[0097] By “an effective amount” is meant the amount of a compound, in a combination according to the invention, required to inhibit the growth of the cells of a neoplasm in vivo. The effective amount of active compound(s) used to practice the present invention for therapeutic treatment of neoplasms (i.e., cancer) varies depending upon the manner of administration, the age, body weight, and general health of the subject. Ultimately, the attending physician or veterinarian will decide the appropriate amount and dosage regimen. Such amount is referred to as an “effective” amount.
[0098] As used herein, the terms “alkyl” and the prefix “alk-” are inclusive of both straight chain and branched chain saturated or unsaturated groups, and of cyclic groups, i.e., cycloalkyl and cycloalkenyl groups. Cyclic groups can be monocyclic or polycyclic and preferably have from 3 to 6 ring carbon atoms, inclusive. Exemplary cyclic groups include cyclopropyl, cyclopentyl, cyclohexyl, and adamantyl groups.
[0099] By “carbo(C 1 -C 6 alkoxy)” is meant an ester fragment of the structure CO 2 R, wherein R is an alkyl group.
[0100] By “carbo(C 6 -C 18 aryl-C 1 -C 6 alkoxy)” is meant an ester fragment of the structure CO 2 R, wherein R is an alkaryl group.
[0101] By “aryl” is meant a C 6 -C 18 carbocyclic aromatic ring or ring system. Examples of aryl groups include phenyl, naphthyl, biphenyl, fluorenyl, and indenyl groups. The term “heteroaryl” means a C 1 -C 9 aromatic ring or ring systems that contains at least one ring heteroatom (e.g., O, S, N). Heteroaryl groups include furyl, thienyl, pyridyl, quinolinyl, tetrazolyl, and imidazolyl groups.
[0102] By “halide” or “halogen” is meant bromine, chlorine, iodine, or fluorine.
[0103] By “heterocycle” is meant a C 1 -C 9 non-aromatic ring or ring system that contains at least one ring heteroatom (e.g., O, S, N). Heterocycles include, for example, pyrrolidinyl, tetrahydrofuranyl, morpholinyl, thiazolidinyl, and imidazolidinyl groups.
[0104] Aryl, heteroaryl, and heterocycle groups may be unsubstituted or substituted by one or more substituents selected from the group consisting of C 1-6 alkyl, hydroxy, halo, nitro, C 1-6 alkoxy, C 1-6 alkylthio, trihalomethyl, C 1-7 acyl, carbonyl, heteroarylcarbonyl, nitrile, C 1-6 alkoxycarbonyl, oxo, alkyl (wherein the alkyl group has from 1 to 6 carbon atoms) and heteroarylalkyl (wherein the alkyl group has from 1 to 6 carbon atoms).
[0105] By “non-vicinal O, S, or N” is meant an oxygen, sulfur, or substituted or unsubstituted nitrogen heteroatom substituent in a linkage, wherein the heteroatom substituent does not form a bond to a saturated carbon that is bonded to another heteroatom.
[0106] By “endo-exonuclease inhibitor” is meant a compound that inhibits (e.g., by at least 10%, 20%, 30%, or more) the enzymatic activity of an enzyme having endo-exonuclease activity. Such inhibitors include, but are not limited to, pentamidine, pentamidine analogs, and pentamidine metabolites.
[0107] By a “low dosage” is meant at least 10% less than the lowest standard recommended dosage of an anti-proliferative agent as recommended by the Physician's Desk Reference , 57th Edition (2003). By a “high dosage” is meant at least 5% more than the highest standard dosage of an anti-proliferative agent. By a “moderate dosage” is meant the dosage between the low dosage and the high dosage.
[0108] By “phosphatase of regenerating liver inhibitor” is meant a compound that inhibits (e.g., by at least 10%, 20%, 30%, or more) the enzymatic activity of a member of the phosphatase of regenerating liver (PRL) family of tyrosine phosphatases. Members of this family include, but are not limited to, PRL-1, PRL-2, and PRL-3. Inhibitors include, but are not limited to, pentamidine, pentamidine analogs, and pentamidine metabolites.
[0109] By “protein tyrosine phosphatase 1B inhibitor” is meant a compound that inhibits (e.g., by at least 10%, 20%, 30%, or more) the enzymatic activity of protein phosphatase 1B. Inhibitors include, but are not limited to, pentamidine, pentamidine analogs, and pentamidine metabolites.
[0110] By an “antiproliferative agent” is meant a compound that, individually, inhibits the growth of a neoplasm. Antiproliferative agents of the invention include alkylating agents, platinum agents, antimetabolites, topoisomerase inhibitors, antitumor antibiotics, antimitotic agents, aromatase inhibitors, thymidylate synthase inhibitors, DNA antagonists, farnesyltransferase inhibitors, pump inhibitors, histone acetyltransferase inhibitors, metalloproteinase inhibitors, ribonucleoside reductase inhibitors, TNF alpha agonists and antagonists, endothelin A receptor antagonists, retinoic acid receptor agonists, immunomodulators, hormonal and antihormonal agents, photodynamic agents, and tyrosine kinase inhibitors. Antiproliferative agents that can be administered in combination with any compound having formula (I) and any compound having formula (II) for treating a neoplasm
[0111] By “Group A antiproliferative agent” is meant an agent listed in Table 1.
TABLE 1 Alkylating agents cyclophosphamide lomustine busulfan procarbazine ifosfamide altretamine melphalan estramustine phosphate hexamethylmelamine mechlorethamine thiotepa streptozocin chlorambucil temozolomide dacarbazine semustine. carmustine Platinum agents cisplatin carboplatinum oxaliplatin ZD-0473 (AnorMED) spiroplatinum, lobaplatin (Aeterna) carboxyphthalatoplatinum, satraplatin (Johnson Matthey) tetraplatin BBR-3464 (Hoffmann-La Roche) ormiplatin SM-11355 (Sumitomo) iproplatin AP-5280 (Access) Antimetabolites azacytidine tomudex gemcitabine trimetrexate capecitabine deoxycoformycin 5-fluorouracil fludarabine floxuridine pentostatin 2-chlorodeoxyadenosine raltitrexed 6-mercaptopurine hydroxyurea 6-thioguanine decitabine (SuperGen) cytarabin clofarabine (Bioenvision) 2-fluorodeoxy cytidine irofulven (MGI Pharma) methotrexate DMDC (Hoffmann-La Roche) idatrexate ethynylcytidine (Taiho) Topoisomerase amsacrine rubitecan (SuperGen) inhibitors epirubicin exatecan mesylate (Daiichi) etoposide quinamed (ChemGenex) teniposide or mitoxantrone gimatecan (Sigma-Tau) irinotecan (CPT-11) diflomotecan (Beaufour-Ipsen) 7-ethyl-10-hydroxy-camptothecin TAS-103 (Taiho) topotecan elsamitrucin (Spectrum) dexrazoxanet (TopoTarget) J-107088 (Merck & Co) pixantrone (Novuspharma) BNP-1350 (BioNumerik) rebeccamycin analogue (Exelixis) CKD-602 (Chong Kun Dang) BBR-3576 (Novuspharma) KW-2170 (Kyowa Hakko) Antitumor dactinomycin (actinomycin D) amonafide antibiotics doxorubicin (adriamycin) azonafide deoxyrubicin anthrapyrazole valrubicin oxantrazole daunorubicin (daunomycin) losoxantrone epirubicin bleomycin sulfate (blenoxane) therarubicin bleomycinic acid idarubicin bleomycin A rubidazone bleomycin B plicamycinp mitomycin C porfiromycin MEN-10755 (Menarini) cyanomorpholinodoxorubicin GPX-100 (Gem Pharmaceuticals) mitoxantrone (novantrone) Antimitotic paclitaxel SB 408075 (GlaxoSmithKline) agents docetaxel E7010 (Abbott) colchicine PG-TXL (Cell Therapeutics) vinblastine IDN 5109 (Bayer) vincristine A 105972 (Abbott) vinorelbine A 204197 (Abbott) vindesine LU 223651 (BASF) dolastatin 10 (NCI) D 24851 (ASTAMedica) rhizoxin (Fujisawa) ER-86526 (Eisai) mivobulin (Warner-Lambert) combretastatin A4 (BMS) cemadotin (BASF) isohomohalichondrin-B (PharmaMar) RPR 109881A (Aventis) ZD 6126 (AstraZeneca) TXD 258 (Aventis) PEG-paclitaxel (Enzon) epothilone B (Novartis) AZ10992 (Asahi) T 900607 (Tularik) IDN-5109 (Indena) T 138067 (Tularik) AVLB (Prescient NeuroPharma) cryptophycin 52 (Eli Lilly) azaepothilone B (BMS) vinflunine (Fabre) BNP-7787 (BioNumerik) auristatin PE (Teikoku Hormone) CA-4 prodrug (OXiGENE) BMS 247550 (BMS) dolastatin-10 (NIH) BMS 184476 (BMS) CA-4 (OXiGENE) BMS 188797 (BMS) taxoprexin (Protarga) Aromatase aminoglutethimide exemestane inhibitors letrozole atamestane (BioMedicines) anastrazole YM-511 (Yamanouchi) formestane Thymidylate pemetrexed (Eli Lilly) nolatrexed (Eximias) synthase inhibitors ZD-9331 (BTG) CoFactor ™ (BioKeys) DNA antagonists trabectedin (PharmaMar) mafosfamide (Baxter International) glufosfamide (Baxter International) apaziquone (Spectrum Pharmaceuticals) albumin + 32P (Isotope Solutions) O6 benzyl guanine (Paligent) thymectacin (NewBiotics) edotreotide (Novartis) Farnesyltransferase arglabin (NuOncology Labs) tipifarnib (Johnson & Johnson) inhibitors lonafarnib (Schering-Plough) perillyl alcohol (DOR BioPharma) BAY-43-9006 (Bayer) Pump inhibitors CBT-1 (CBA Pharma) zosuquidar trihydrochloride (Eli Lilly) tariquidar (Xenova) biricodar dicitrate (Vertex) MS-209 (Schering AG) Histone tacedinaline (Pfizer) pivaloyloxymethyl butyrate (Titan) acetyltransferase SAHA (Aton Pharma) depsipeptide (Fujisawa) inhibitors MS-275 (Schering AG) Metalloproteinase Neovastat (Aeterna Laboratories) CMT-3 (CollaGenex) inhibitors marimastat (British Biotech) BMS-275291 (Celltech) Ribonucleoside gallium maltolate (Titan) tezacitabine (Aventis) reductase inhibitors triapine (Vion) didox (Molecules for Health) TNF alpha virulizin (Lorus Therapeutics) revimid (Celgene) agonists/antagonists CDC-394 (Celgene) Endothelin A atrasentan (Abbott) YM-598 (Yamanouchi) receptor antagonist ZD-4054 (AstraZeneca) Retinoic acid fenretinide (Johnson & Johnson) alitretinoin (Ligand) receptor agonists LGD-1550 (Ligand) Immuno- interferon dexosome therapy (Anosys) modulators oncophage (Antigenics) pentrix (Australian Cancer Technology) GMK (Progenics) ISF-154 (Tragen) adenocarcinoma vaccine (Biomira) cancer vaccine (Intercell) CTP-37 (AVI BioPharma) norelin (Biostar) IRX-2 (Immuno-Rx) BLP-25 (Biomira) PEP-005 (Peplin Biotech) MGV (Progenics) synchrovax vaccines (CTL Immuno) β-alethine (Dovetail) melanoma vaccine (CTL Immuno) CLL therapy (Vasogen) p21 RAS vaccine (GemVax) Hormonal and estrogens prednisone antihormonal conjugated estrogens methylprednisolone agents ethinyl estradiol prednisolone chlortrianisen aminoglutethimide idenestrol leuprolide hydroxyprogesterone caproate goserelin medroxyprogesterone leuporelin testosterone bicalutamide testosterone propionate; fluoxymesterone flutamide methyltestosterone octreotide diethylstilbestrol nilutamide megestrol mitotane tamoxifen P-04 (Novogen) toremofine 2-methoxyestradiol (EntreMed) dexamethasone arzoxifene (Eli Lilly) Photodynamic talaporfin (Light Sciences) Pd-bacteriopheophorbide (Yeda) agents Theralux (Theratechnologies) lutetium texaphyrin (Pharmacyclics) motexafin gadolinium (Pharmacyclics) hypericin Tyrosine Kinase imatinib (Novartis) kahalide F (PharmaMar) Inhibitors leflunomide (Sugen/Pharmacia) CEP-701 (Cephalon) ZD1839 (AstraZeneca) CEP-751 (Cephalon) erlotinib (Oncogene Science) MLN518 (Millenium) canertinib (Pfizer) PKC412 (Novartis) squalamine (Genaera) phenoxodiol () SU5416 (Pharmacia) trastuzumab (Genentech) SU6668 (Pharmacia ) C225 (ImClone) ZD4190 (AstraZeneca) rhu-Mab (Genentech) ZD6474 (AstraZeneca) MDX-H210 (Medarex) vatalanib (Novartis) 2C4 (Genentech) PKI166 (Novartis) MDX-447 (Medarex) GW2016 (GlaxoSmithKline) ABX-EGF (Abgenix) EKB-509 (Wyeth) IMC-1C11 (ImClone) EKB-569 (Wyeth) Miscellaneous agents SR-27897 (CCK A inhibitor, Sanofi-Synthelabo) BCX-1777 (PNP inhibitor, BioCryst) tocladesine (cyclic AMP agonist, Ribapharm) ranpirnase (ribonuclease stimulant, Alfacell) alvocidib (CDK inhibitor, Aventis) galarubicin (RNA synthesis inhibitor, Dong-A) CV-247 (COX-2 inhibitor, Ivy Medical) tirapazamine (reducing agent, SRI International) P54 (COX-2 inhibitor, Phytopharm) N-acetylcysteine (reducing agent, Zambon) CapCell ™ (CYP450 stimulant, Bavarian Nordic) R-flurbiprofen (NF-kappaB inhibitor, Encore) GCS-100 (gal3 antagonist, GlycoGenesys) 3CPA (NF-kappaB inhibitor, Active Biotech) G17DT immunogen (gastrin inhibitor, Aphton) seocalcitol (vitamin D receptor agonist, Leo) efaproxiral (oxygenator, Allos Therapeutics) 131-I-TM-601 (DNA antagonist, TransMolecular) PI-88 (heparanase inhibitor, Progen) eflornithine (ODC inhibitor, ILEX Oncology) tesmilifene (histamine antagonist, YM BioSciences) minodronic acid (osteoclast inhibitor, Yamanouchi) histamine (histamine H2 receptor agonist, Maxim) indisulam (p53 stimulant, Eisai) tiazofurin (IMPDH inhibitor, Ribapharm) aplidine (PPT inhibitor, PharmaMar) cilengitide (integrin antagonist, Merck KGaA) rituximab (CD20 antibody, Genentech) SR-31747 (IL-1 antagonist, Sanofi-Synthelabo) gemtuzumab (CD33 antibody, Wyeth Ayerst) CCI-779 (mTOR kinase inhibitor, Wyeth) PG2 (hematopoiesis enhancer, Pharmagenesis) exisulind (PDE V inhibitor, Cell Pathways) Immunol ™ (triclosan oral rinse, Endo) CP-461 (PDE V inhibitor, Cell Pathways) triacetyluridine (uridine prodrug, Wellstat) AG-2037 (GART inhibitor, Pfizer) SN-4071 (sarcoma agent, Signature BioScience) WX-UK1 (plasminogen activator inhibitor, Wilex) TransMID-107 ™ (immunotoxin, KS Biomedix) PBI-1402 (PMN stimulant, ProMetic LifeSciences) PCK-3145 (apoptosis promotor, Procyon) bortezomib (proteasome inhibitor, Millennium) doranidazole (apoptosis promotor, Pola) SRL-172 (T cell stimulant, SR Pharma) CHS-828 (cytotoxic agent, Leo) TLK-286 (glutathione S transferase inhibitor, Telik) trans-retinoic acid (differentiator, NIH) PT-100 (growth factor agonist, Point Therapeutics) MX6 (apoptosis promotor, MAXIA) midostaurin (PKC inhibitor, Novartis) apomine (apoptosis promotor, ILEX Oncology) bryostatin-1 (PKC stimulant, GPC Biotech) urocidin (apoptosis promotor, Bioniche) CDA-II (apoptosis promotor, Everlife) Ro-31-7453 (apoptosis promotor, La Roche) SDX-101 (apoptosis promotor, Salmedix) brostallicin (apoptosis promotor, Pharmacia) ceflatonin (apoptosis promotor, ChemGenex)
[0112] Compounds useful in the invention include those described herein in any of their pharmaceutically acceptable forms, including isomers such as diastereomers and enantiomers, salts, solvates, and polymorphs, thereof, as well as racemic mixtures of the compounds described herein.
[0113] Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0114] [0114]FIG. 1 is a chart demonstrating the effectiveness of a chlorpromazine/pentamidine combination (5 mg/Kg chlorpromazine and 20 mg/Kg pentamidine) administered to female SCID mice that have A549 human lung tumor xenografts.
[0115] [0115]FIG. 2 is a chart demonstrating the effectiveness of a chlorpromazine/pentamidine combination (5 mg/Kg chlorpromazine and 20 mg/Kg pentamidine) administered to male SCID mice that have A549 human lung tumor xenografts, with treatment consisting of a three week treatment period, followed by a one week no-treatment period, followed by a two week treatment period.
DETAILED DESCRIPTION
[0116] We have discovered that the combination of the antipsychotic drug chlorpromazine and the antiprotozoal drug pentamidine (heretofore referred to as “C/P combination”) exhibits substantial antiproliferative activity against cancer cells, and that the concentrations that exhibited maximal antiproliferative activity against cancer cells were not toxic to normal cells.
[0117] When used in concert with an anti-proliferative agent, the C/P combination may also enhance the efficacy of the anti-proliferative agent such that the dosage of the anti-proliferative compound is lowered to achieve the same therapeutic benefit, thereby moderating any unwanted side effects. Preferably, a moderate dose, and most preferably, a low dose of the anti-proliferative agent would be used in such a case. Alternatively, the C/P combination may be used to augment the efficacy of an anti-proliferative compound at its normal dose, such that an increased therapeutic benefit is obtained. In addition, when used with an anti-proliferative agent, the C/P combination may be useful in improving the ability of that agent to overcome neoplasm drug resistance. Thus, the C/P combination is useful for the treatment of cancer and other neoplasms and may find further benefit when used with an anti-proliferative agent.
[0118] Based on known properties that are shared between chlorpromazine and its analogs and metabolites, and between pentamidine and its analogs and metabolites, it is likely that structurally related compounds can be substituted for chlorpromazine and/or pentamidine in the antiproliferative combinations of the invention. Information regarding each of the drugs and its analogs and metabolites is provided below.
[0119] Phenothiazines
[0120] Phenothiazines that are useful in the antiproliferative combination of the invention as chlorpromazine analogs are compounds having the general formula (I):
[0121] or a pharmaceutically acceptable salt thereof,
[0122] wherein R 2 is selected from the group consisting of: CF 3 , halo, OCH 3 , COCH 3 , CN, OCF 3 , COCH 2 CH 3 , CO(CH 2 ) 2 CH 3 , and SCH 2 CH 3 ;
[0123] R 9 has the formula:
[0124] wherein n is 0 or 1, each of R 32 , R 33 , and R 34 is, independently, H or substituted or unsubstituted C 1-6 alkyl, and Z is NR 35 R 36 or OR 37 , wherein each of R 35 and R 36 is, independently, H, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted alkaryl, substituted or unsubstituted alkheteroaryl, and R 37 is H, C 1-6 alkyl, or C 1-7 acyl, wherein any of R 33 , R 34 , R 35 , and R 36 can be optionally taken together with intervening carbon or non-vicinal O, S, or N atoms to form one or more five- to seven-membered rings, substituted with one or more hydrogens, substituted or unsubstituted C 1-6 alkyl groups, C 6-12 aryl groups, alkoxy groups, halogen groups, substituted or unsubstituted alkaryl groups, or substituted or unsubstituted alkheteroaryl groups;
[0125] each of R 1 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 is independently H, OH, F, OCF 3 , or OCH 3 ; and W is selected from the group consisting of:
[0126] In preferred compounds, R 2 is Cl; each of R 1 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 is H or F; and R 9 is selected from the group consisting of:
[0127] More preferably, each of R 1 , R 4 , R 5 , R 6 , and R 8 is H.
[0128] The most commonly prescribed member of the phenothiazine family is chlorpromazine, which has the structure:
[0129] Chlorpromazine is currently available in the following forms: tablets, capsules, suppositories, oral concentrates and syrups, and formulations for injection.
[0130] Phenothiazines considered to be chlorpromazine analogs include fluphenazine, prochlorperazine, promethazine, thioridazine, and trifluoperazine. Many of these share antipsychotic or antiemetic activity with chlorpromazine. Also included as chlorpromazine analogs are those compounds in PCT Application WO/02057244, which is hereby incorporated by reference.
[0131] Phenothiazines are thought to elicit their antipsychotic and antiemetic effects via interference with central dopaminergic pathways in the mesolimbic and medullary chemoreceptor trigger zone areas of the brain. Extrapyramidal side effects are a result of interactions with dopaminergic pathways in the basal ganglia. Although often termed dopamine blockers, the exact mechanism of dopaminergic interference responsible for the drugs' antipsychotic activity has not been determined.
[0132] Phenothiazines are also known to inhibit the activity of protein kinase C. Protein kinase C mediates the effects of a large number of hormones and is involved in may aspects of cellular regulation and carcinogenesis (Castagna, et al., J. Biol. Chem . 1982, 257:7847-51). The enzyme is also thought to play a role in certain types of resistance to cancer chemotherapeutic agents. Chlorpromazine has been investigated for the inhibition of protein kinase C both in vitro (Aftab, et al., Mol. Pharmacology , 1991, 40:798-805) and in vivo (Dwivedi, et al., J. Pharm. Exp. Ther ., 1999, 291:688-704).
[0133] Chlorpromazine also has strong alpha-adrenergic blocking activity and can cause orthostatic hypotension. Chlorpromazine also has moderate anticholinergic activity manifested as occasional dry mouth, blurred vision, urinary retention, and constipation. Chlorpromazine increases prolactin secretion owing to its dopamine receptor blocking action in the pituitary and hypothalamus.
[0134] Chlorpromazine is readily absorbed from the gastrointestinal tract. Its bioavailability is variable due to considerable first pass metabolism by the liver. Liquid concentrates may have greater bioavailability than tablets. Food does not appear to affect bioavailability consistently. I.m. administration bypasses much of the first pass effect and higher plasma concentrations are achieved. The onset of action after i.m. administration is usually 15 to 30 minutes and after oral administration 30 to 60 minutes. Rectally administered chlorpromazine usually takes longer to act than orally administered chlorpromazine.
[0135] Chlorpromazine Metabolites
[0136] Because chlorpromazine undergoes extensive metabolic transformation into a number of metabolites that may be therapeutically active, these metabolites may be substituted from chlorpromazine in the antiproliferative combination of the invention. The metabolism of chlorpromazine yields, for example, oxidative N-demethylation to yield the corresponding primary and secondary amine, aromatic oxidation to yield a phenol, N-oxidation to yield the N-oxide, S-oxidation to yield the sulphoxide or sulphone, oxidative deamination of the aminopropyl side chain to yield the phenothiazine nuclei, and glucuronidation of the phenolic hydroxy groups and tertiary amino group to yield a quaternary ammonium glucuronide.
[0137] In other examples of chlorpromazine metabolites useful in the antiproliferative combination of the invention, each of positions 3, 7, and 8 of the phenothiazine can independently be substituted with a hydroxyl or methoxyl moiety.
[0138] Pentamidine
[0139] Pentamidine is currently used for the treatment of Pneumocystis carinii, Leishmania donovani, Trypanosoma brucei, T. gambiense , and T. rhodesiense infections. The structure of pentamidine is:
[0140] It is available formulated for injection or inhalation. For injection, pentamidine is packaged as a nonpyrogenic, lyophilized product. After reconstitution, it is administered by intramuscular or intravenous injection.
[0141] Pentamidine isethionate is a white, crystalline powder soluble in water and glycerin and insoluble in ether, acetone, and chloroform. It is chemically designated 4,4′-diamidino-diphenoxypentane di(β-hydroxyethanesulfonate). The molecular formula is C 23 H 36 N 4 O 10 S 2 and the molecular weight is 592.68.
[0142] The mode of action of pentamidine is not fully understood. In vitro studies with mammalian tissues and the protozoan Crithidia oncopelti indicate that the drug interferes with nuclear metabolism, producing inhibition of the synthesis of DNA, RNA, phospholipids, and proteins. Several lines of evidence suggest that the action of pentamidine against leishmaniasis, a tropical disease caused by a protozoan residing in host macrophages, might be mediated via host cellular targets and the host immune system. Pentamidine selectively targets intracellular leishmania in macrophages but not the free-living form of the protozoan and has reduced anti-leishmania activity in immunodeficient mice in comparison with its action in immunocompetent hosts.
[0143] Recently, pentamidine was shown to be an effective inhibitor of protein tyrosine phosphatase 1B (PTP1B). Because PTP1B dephosphorylates and inactivates Jak kinases, which mediate signaling of cytokines with leishmanicidal activity, its inhibition by pentamidine might result in augmentation of cytokine signaling and anti-leishmania effects. Pentamidine has also been shown to be a potent inhibitor of the oncogenic phosphatases of regenerating liver (PRL). Pentamidine has also been shown to inhibit the activity of endo-exonuclease (PCT Publication No. WO 01/35935). Thus, in the methods of the invention, pentamidine can be replaced by any PTP1B inhibitor, PRL inhibitor, or endo-exonuclease inhibitor.
[0144] Little is known about the drug's pharmacokinetics. In seven patients treated with daily intramuscular doses of pentamidine at 4 mg/kg for 10 to 12 days, plasma concentrations were between 0.3 and 0.5 μg/mL. The patients continued to excrete decreasing amounts of pentamidine in urine up to six to eight weeks after cessation of the treatment.
[0145] Tissue distribution of pentamidine has been studied in mice given a single intraperitoneal injection of pentamidine at 10 mg/kg. The concentration in the kidneys was the highest, followed by that in the liver. In mice, pentamidine was excreted unchanged, primarily via the kidneys with some elimination in the feces. The ratio of amounts excreted in the urine and feces (4:1) was constant over the period of study.
[0146] Pentamidine Analogs
[0147] Aromatic diamidino compounds can replace pentamidine in the antiproliferative combination of the invention. Aromatic diamidino compounds such as propamidine, butamidine, heptamidine, and nonamidine share properties with pentamidine in that they exhibit antipathogenic or DNA binding properties. Other analogs (e.g., stilbamidine and indole analogs of stilbamidine, hydroxystilbamidine, diminazene, benzamidine, 4,4′-(pentamethylenedioxy)phenamidine, dibrompropamidine, 1,3-bis(4-amidino-2-methoxyphenoxy)propane (DAMP), netropsin, distamycin, phenamidine, amicarbalide, bleomycin, actinomycin, and daunorubicin) also exhibit properties similar to those of pentamidine. It is likely that these compounds will have anti-cancer activity when administered in combination with chlorpromazine (or an analog or metabolite of chlorpromazine).
[0148] Pentamidine analogs are described, for example, by formula (II)
[0149] wherein A is
[0150] wherein
[0151] each of X and Y is, independently, O, NR 19 , or S,
[0152] each of R 14 and R 19 is, independently, H or C 1 -C 6 alkyl,
[0153] each of R 15 , R 16 , R 17 , and R 18 is, independently, H, C 1 -C 6 alkyl, halogen,
[0154] C 1 -C 6 alkyloxy, C 6 -C 18 aryloxy, or C 6 -C 18 aryl-C 1 -C 6 alkyloxy,
[0155] p is an integer between 2 and 6, inclusive,
[0156] each of m and n is, independently, an integer between 0 and 2, inclusive,
[0157] each of R 10 and R 11 is
[0158] wherein
[0159] R 21 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy-C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl, R 22 is H, C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, carbo(C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryl C 1 -C 6 alkyloxy), carbo(C 6 -C 18 aryloxy), or C 6 -C 18 aryl, and R 20 is H, OH, or C 1 -C 6 alkyloxy, or R 20 and R 21 together represent
[0160] wherein
[0161] each of R 23 , R 24 , and R 25 is, independently, H, C 1 -C 6 alkyl, halogen, or trifluoromethyl, each of R 26 , R 27 , R 28 , and R 29 is, independently, H or C 1 -C 6 alkyl, and R 30 is H, halogen, trifluoromethyl, OCF 3 , NO 2 , C 1 -C 6 alkyl, C 1 -C 8 cycloalkyl, C 1 -C 6 alkyloxy, C 1 -C 6 alkoxy C 1 -C 6 alkyl, hydroxy C 1 -C 6 alkyl, C 1 -C 6 alkylamino C 1 -C 6 alkyl, amino C 1 -C 6 alkyl, or C 6 -C 18 aryl,
[0162] each of R 12 and R 13 is, independently, H, Cl, Br, OH, OCH 3 , OCF 3 , NO 2 , and NH 2 , or R 12 and R 13 together form a single bond.
[0163] Other analogs include stilbamidine (G-1) and hydroxystilbamidine (G-2), and their indole analogs (e.g., G-3).
[0164] Each amidine moiety in G-1, G-2, or G-3 may be replaced with one of the moieties depicted in formula (I) above as
[0165] As is the case for pentamidine, salts of stilbamidine and its related compounds are also useful in the method of the invention. Preferred salts include, for example, dihydrochloride and methanesulfonate salts.
[0166] Still other analogs are those that fall within a formula provided in any of U.S. Pat. Nos. 5,428,051; 5,521,189; 5,602,172; 5,643,935; 5,723,495; 5,843,980; 6,008,247; 6,025,398; 6,172,104; 6,214,883; and 6,326,395, or U.S. patent application Ser. Nos. US 2001/0044468 A1 and US 2002/0019437 A1, each of which is in its entirety incorporated by reference.
[0167] Exemplary analogs are 1,3-bis(4-amidino-2-methoxyphenoxy)propane, phenamidine, amicarbalide, 1,5-bis(4′-(N-hydroxyamidino)phenoxy)pentane, 1,3-bis(4′-(N-hydroxyamidino)phenoxy)propane, 1,3-bis(2′-methoxy-4′-(N-hydroxyamidino)phenoxy)propane, 1,4-bis(4′-(N-hydroxyamidino)phenoxy)butane, 1,5-bis(4′-(N-hydroxyamidino)phenoxy)pentane, 1,4-bis(4′-(N-hydroxyamidino)phenoxy)butane, 1,3-bis(4′-(4-hydroxyamidino)phenoxy)propane, 1,3-bis(2′-methoxy-4′-(N-hydroxyamidino)phenoxy)propane, 2,5-bis[4-amidinophenyl]furan, 2,5-bis[4-amidinophenyl]furan-bis-amidoxime, 2,5-bis[4-amidinophenyl]furan-bis-O-methylamidoxime, 2,5-bis[4-amidinophenyl]furan-bis-O-ethylamidoxime, 2,5-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,5-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,4-bis(4-amidinophenyl)furan, 2,4-bis(4-amidinophenyl)furan-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)furan-bis-O-4-fluorophenyl, 2,4-bis(4-amidinophenyl)furan-bis-O-4-methoxyphenyl, 2,5-bis(4-amidinophenyl) thiophene, 2,5-bis(4-amidinophenyl) thiophene-bis-O-methylamidoxime, 2,4-bis(4-amidinophenyl)thiophene, 2,4-bis(4-amidinophenyl)thiophene-bis-O-methylamidoxime, 2,8-diamidinodibenzothiophene, 2,8-bis(N-isopropylamidino)carbazole, 2,8-bis(N-hydroxyamidino)carbazole, 2,8-bis(2-imidazolinyl)dibenzothiophene, 2,8-bis(2-imidazolinyl)-5,5-dioxodibenzothiophene, 3,7-diamidinodibenzothiophene, 3,7-bis(N-isopropylamidino)dibenzothiophene, 3,7-bis(N-hydroxyamidino)dibenzothiophene, 3,7-diaminodibenzothiophene, 3,7-dibromodibenzothiophene, 3,7-dicyanodibenzothiophene, 2,8-diamidinodibenzofuran, 2,8-di(2-imidazolinyl)dibenzofuran, 2,8-di(N-isopropylamidino)dibenzofuran, 2,8-di(N-hydroxylamidino)dibenzofuran, 3,7-di(2-imidazolinyl)dibenzofuran, 3,7-di(isopropylamidino)dibenzofuran, 3,7-di(N-hydroxylamidino)dibenzofuran, 2,8-dicyanodibenzofuran, 4,4′-dibromo-2,2′-dinitrobiphenyl, 2-methoxy-2′-nitro-4,4′-dibromobiphenyl, 2-methoxy-2′-amino-4,4′-dibromobiphenyl, 3,7-dibromodibenzofuran, 3,7-dicyanodibenzofuran, 2,5-bis(5-amidino-2-benzimidazolyl)pyrrole, 2,5-bis[5-(2-imidazolinyl)-2-benzimidazolyl]pyrrole, 2,6-bis[5-(2-imidazolinyl)-2-benzimidazolyl]pyridine, 1-methyl-2,5-bis(5-amidino-2-benzimidazolyl)pyrrole, 1-methyl-2,5-bis[5-(2-imidazolyl)-2-benzimidazolyl]pyrrole, 1-methyl-2,5-bis[5-(1,4,5,6-tetrahydro-2-pyrimidinyl)-2-benzimidazolyl]pyrrole, 2,6-bis(5-amidino-2-benzimidazoyl)pyridine, 2,6-bis[5-(1,4,5,6-tetrahydro-2-pyrimidinyl)-2-benzimidazolyl]pyridine, 2,5-bis(5-amidino-2-benzimidazolyl)furan, 2,5-bis-[5-(2-imidazolinyl)-2-benzimidazolyl]furan, 2,5-bis-(5-N-isopropylamidino-2-benzimidazolyl)furan, 2,5-bis-(4-guanylphenyl)furan, 2,5-bis(4-guanylphenyl)-3,4-dimethylfuran, 2,5-bis{p-[2-(3,4,5,6-tetrahydropyrimidyl)phenyl]}furan, 2,5-bis[4-(2-imidazolinyl)phenyl]furan, 2,5[bis-{4-(2-tetrahydropyrimidinyl)}phenyl]-3-(p-tolyloxy)furan, 2,5[bis{4-(2-imidazolinyl)}phenyl]-3-(p-tolyloxy)furan, 2,5-bis{4-[5-(N-2-aminoethylamido)benzimidazol-2-yl]phenyl}furan, 2,5-bis[4-(3a,4,5,6,7,7a-hexahydro-1H-benzimidazol-2-yl)phenyl]furan, 2,5-bis[4-(4,5,6,7-tetrahydro-1H-1,3-diazepin-2-yl)phenyl]furan, 2,5-bis(4-N,N-dimethylcarboxhydrazidephenyl)furan, 2,5-bis{4-[2-(N-2-hydroxyethyl)imidazolinyl]phenyl}furan, 2,5-bis[4-(N-isopropylamidino)phenyl]furan, 2,5-bis{4-[3-(dimethylaminopropyl)amidino]phenyl}furan, 2,5-bis{4-[N-(3-aminopropyl)amidino]phenyl}furan, 2,5-bis[2-(imidzaolinyl)phenyl]-3,4-bis(methoxymethyl)furan, 2,5-bis[4-N-(dimethylaminoethyl)guanyl]phenylfuran, 2,5-bis{4-[(N-2-hydroxyethyl)guanyl]phenyl}furan, 2,5-bis[4-N-(cyclopropylguanyl)phenyl]furan, 2,5-bis[4-(N,N-diethylaminopropyl)guanyl]phenylfuran, 2,5-bis{4-[2-(N-ethylimidazolinyl)]phenyl}furan, 2,5-bis{4-[N-(3-pentylguanyl)]}phenylfuran, 2,5-bis[4-(2-imidazolinyl)phenyl]-3-methoxyfuran, 2,5-bis[4-(N-isopropylamidino)phenyl]-3-methylfuran, bis[5-amidino-2-benzimidazolyl]methane, bis[5-(2-imidazolyl)-2-benzimidazolyl]methane, 1,2-bis[5-amidino-2-benzimidazolyl]ethane, 1,2-bis[5-(2-imidazolyl)-2-benzimidazolyl]ethane, 1,3-bis[5-amidino-2-benzimidazolyl]propane, 1,3-bis[5-(2-imidazolyl)-2-benzimidazolyl]propane, 1,4-bis[5-amidino-2-benzimidazolyl]propane, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]butane, 1,8-bis[5-amidino-2-benzimidazolyl]octane, trans-1,2-bis[5-amidino-2-benzimidazolyl]ethene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1-methylbutane, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2-ethylbutane, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1-methyl-1-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2,3-diethyl-2-butene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-1,3-butadiene, 1,4-bis[5-(2-imidazolyl)-2-benzimidazolyl]-2-methyl-1,3-butadiene, bis[5-(2-pyrimidyl)-2-benzimidazolyl]methane, 1,2-bis[5-(2-pyrimidyl)-2-benzimidazolyl]ethane, 1,3-bis[5-amidino-2-benzimidazolyl]propane, 1,3-bis[5-(2-pyrimidyl)-2-benzimidazolyl]propane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]butane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1-methylbutane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2-ethylbutane, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1-methyl-1-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2,3-diethyl-2-butene, 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-1,3-butadiene, and 1,4-bis[5-(2-pyrimidyl)-2-benzimidazolyl]-2-methyl-1,3-butadiene, 2,4-bis(4-guanylphenyl)pyrimidine, 2,4-bis(4-imidazolin-2-yl)pyrimidine, 2,4-bis[(tetrahydropyrimidinyl-2-yl)phenyl]pyrimidine, 2-(4-[N-i-propylguanyl]phenyl)-4-(2-methoxy-4-[N-i-propylguanyl]phenyl)pyrimidine, 4-(N-cyclopentylamidino)-1,2-phenylene diamine, 2,5-bis-[2-(5-amidino)benzimidazoyl]furan, 2,5-bis[2-{5-(2-imidazolino)}benzimidazoyl]furan, 2,5-bis[2-(5-N-isopropylamidino)benzimidazoyl]furan, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]furan, 2,5-bis[2-(5-amidino)benzimidazoyl]pyrrole, 2,5-bis[2-{5-(2-imidazolino)}benzimidazoyl]pyrrole, 2,5-bis[2-(5-N-isopropylamidino)benzimidazoyl]pyrrole, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]pyrrole, 1-methyl-2,5-bis[2-(5-amidino)benzimidazoyl]pyrrole, 2,5-bis[2-{5-(2-imidazolino)}benzimidazoyl]-1-methylpyrrole, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]-1-methylpyrrole, 2,5-bis[2-(5-N-isopropylamidino)benzimidazoyl]thiophene, 2,6-bis[2-{5-(2-imidazolino)}benzimidazoyl]pyridine, 2,6-bis[2-(5-amidino)benzimidazoyl]pyridine, 4,4′-bis[2-(5-N-isopropylamidino)benzimidazoyl]-1,2-diphenylethane, 4,4′-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]-2,5-diphenylfuran, 2,5-bis[2-(5-amidino)benzimidazoyl]benzo[b]furan, 2,5-bis[2-(5-N-cyclopentylamidino)benzimidazoyl]benzo[b]furan, 2,7-bis[2-(5-N-isopropylamidino)benzimidazoyl]fluorene, 2,5-bis[4-(3-(N-morpholinopropyl)carbamoyl)phenyl]furan, 2,5-bis[4-(2-N,N-dimethylaminoethylcarbamoyl)phenyl]furan, 2,5-bis[4-(3-N,N-dimethylaminopropylcarbamoyl)phenyl]furan, 2,5-bis[4-(3-N-methyl-3-N-phenylaminopropylcarbamoyl)phenyl]furan, 2,5-bis[4-(3-N,N 8 ,N 11 -trimethylaminopropylcarbamoyl)phenyl]furan, 2,5-bis[3-amidinophenyl]furan, 2,5-bis[3-(N-isopropylamidino)amidinophenyl]furan, 2,5-bis[3[(N-(2-dimethylaminoethyl)amidino]phenylfuran, 2,5-bis[4-(N-2,2,2-trichloroethoxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-thioethylcarbonyl) amidinophenyl]furan, 2,5-bis[4-(N-benzyloxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-phenoxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-(4-fluoro)-phenoxycarbonyl)amidinophenyl]furan, 2,5-bis[4-(N-(4-methoxy)phenoxycarbonyl)amidinophenyl]furan, 2,5-bis[4(1-acetoxyethoxycarbonyl)amidinophenyl]furan, and 2,5-bis[4-(N-(3-fluoro)phenoxycarbonyl)amidinophenyl]furan. Methods for making any of the foregoing compounds are described in U.S. Pat. Nos. 5,428,051; 5,521,189; 5,602,172; 5,643,935; 5,723,495; 5,843,980; 6,008,247; 6,025,398; 6,172,104; 6,214,883; and 6,326,395, an U.S. patent application Ser. Nos. US 2001/0044468 A1 and US 2002/0019437 A1.
[0168] Pentamidine Metabolites
[0169] Pentamidine metabolites are also useful in the antiproliferative combination of the invention. Pentamidine is rapidly metabolized in the body to at least seven primary metabolites. Some of these metabolites share one or more activities with pentamidine. It is likely that some pentamidine metabolites will have anti-cancer activity when administered in combination with an antiproliferative agent. Seven pentamidine metabolites (H-1 through H-7) are shown below.
[0170] Therapy
[0171] The compounds of the invention are useful for the treatment of neoplasms. Therapy may be performed alone or in conjunction with another therapy (e.g., surgery, radiation therapy, chemotherapy, immunotherapy, anti-angiogenesis therapy, or gene therapy). For example, useful chemotherapeutic agents that can be used in conjunction with pentamidine or a pentamidine analog and chlorpromazine or a chlorpromazine analog are listed in Table (I) and are referred to a “Group A antiproliferative agents.”
[0172] The duration of the combination therapy depends on the type of disease or disorder being treated, the age and condition of the patient, the stage and type of the patient's disease, and how the patient responds to the treatment. Therapy may be given in on-and-off cycles that include rest periods so that the patient's body has a chance to recovery from any as yet unforeseen side-effects.
[0173] Examples of cancers and other neoplasms include, without limitation, leukemias (e.g., acute leukemia, acute lymphocytic leukemia, acute myelocytic leukemia, acute myeloblastic leukemia, acute promyelocytic leukemia, acute myelomonocytic leukemia, acute monocytic leukemia, acute erythroleukemia, chronic leukemia, chronic myelocytic leukemia, chronic lymphocytic leukemia), polycythemia vera, lymphoma (Hodgkin's disease, non-Hodgkin's disease), Waldenstrom's macroglobulinemia, heavy chain disease, and solid tumors such as sarcomas and carcinomas (e.g., fibrosarcoma, myxosarcoma, liposarcoma, chondrosarcoma, osteogenic sarcoma, chordoma, angiosarcoma, endotheliosarcoma, lymphangiosarcoma, lymphangioendotheliosarcoma, synovioma, mesothelioma, Ewing's tumor, leiomyosarcoma, rhabdomyosarcoma, colon carcinoma, pancreatic cancer, breast cancer, ovarian cancer, prostate cancer, squamous cell carcinoma, basal cell carcinoma, adenocarcinoma, sweat gland carcinoma, sebaceous gland carcinoma, papillary carcinoma, papillary adenocarcinomas, cystadenocarcinoma, medullary carcinoma, bronchogenic carcinoma, renal cell carcinoma, hepatoma, bile duct carcinoma, choriocarcinoma, seminoma, embryonal carcinoma, Wilm's tumor, cervical cancer, uterine cancer, testicular cancer, lung carcinoma, small cell lung carcinoma, bladder carcinoma, epithelial carcinoma, glioma, astrocytoma, medulloblastoma, craniopharyngioma, ependymoma, pinealoma, hemangioblastoma, acoustic neuroma, oligodenriglioma, schwannoma, meningioma, melanoma, neuroblastoma, and retinoblastoma).
[0174] Formulation of Pharmaceutical Compositions
[0175] The administration of each compound of the combination may be by any suitable means that results in a concentration of the compound that, combined with the other component, is anti-neoplastic upon reaching the target region. The compound may be contained in any appropriate amount in any suitable carrier substance, and is generally present in an amount of 1-95% by weight of the total weight of the composition. The composition may be provided in a dosage form that is suitable for the oral, parenteral (e.g., intravenously, intramuscularly), rectal, cutaneous, nasal, vaginal, inhalant, skin (patch), or ocular administration route. Thus, the composition may be in the form of, e.g., tablets, capsules, pills, powders, granulates, suspensions, emulsions, solutions, gels including hydrogels, pastes, ointments, creams, plasters, drenches, osmotic delivery devices, suppositories, enemas, injectables, implants, sprays, or aerosols. The pharmaceutical compositions may be formulated according to conventional pharmaceutical practice (see, e.g., Remington: The Science and Practice of Pharmacy , 20th edition, 2000, ed. A. R. Gennaro, Lippincott Williams & Wilkins, Philadelphia, and Encyclopedia of Pharmaceutical Technology , eds. J. Swarbrick and J. C. Boylan, 1988-1999, Marcel Dekker, New York).
[0176] Dosages
[0177] The dosage of each compound of the claimed combinations depends on several factors, including: the administration method, the neoplasm to be treated, the severity of the neoplasm, whether the neoplasm is to be treated or prevented, and the age, weight, and health of the patient to be treated.
[0178] For combinations that include an anti-proliferative agent in addition to a chlorpromazine/chlorpromazine analog and pentamidine/pentamidine analog combination, the recommended dosage for the anti-proliferative agent is desirably less than or equal to the recommended dose as given in the Physician's Desk Reference , 57 th Edition (2003).
[0179] As described above, the compound in question may be administered orally in the form of tablets, capsules, elixirs or syrups, or rectally in the form of suppositories. Parenteral administration of a compound is suitably performed, for example, in the form of saline solutions or with the compound incorporated into liposomes. In cases where the compound in itself is not sufficiently soluble to be dissolved, a solubilizer such as ethanol can be applied. Below, for illustrative purposes, the dosages for chlorpromazine and pentamidine are described. One in the art will recognize that if a second compound is substituted for either chlorpromazine or pentamidine, the correct dosage can be determined by examining the efficacy of the compound in cell proliferation assays, as well as its toxicity in humans.
[0180] A chemotherapeutic agent of the invention is usually given by the same route of administration that is known to be effective for delivering it as a monotherapy. For example, when used in combination therapy with pentamidine or a pentamidine analog and chlorpromazine or a chlorpromazine analog according to the methods of this invention, a Group A antiproliferative agent is dosed in amounts and frequencies equivalent to or less than those that result in its effective monotherapeutic use.
[0181] Oral Administration
[0182] For chlorpromazine or a chlorpromazine analog adapted for oral administration for systemic use, the dosage is normally about 0.1 mg to 1000 mg per dose administered (preferably about 0.5 mg to 500 mg, and more preferably about 1 mg to 300 mg) one to ten times daily (preferably one to 5 times daily) for one day to one year, and may even be for the life of the patient; because the combinations of the invention function primarily as cytostatic rather than cytotoxic agents, and exhibit low toxicity, chronic, long-term administration will be indicated in many cases. Dosages up to 2 g per day may be necessary.
[0183] For pentamidine or a pentamidine analog, the dosage is normally about 0.1 mg to 300 mg per dose administered (preferably about 1 mg to 100 mg) one to four times daily for one day to one year, and, like chlorpromazine, may be administered for the life of the patient. Administration may also be given in cycles, such that there are periods during which time pentamidine is not administered. This period could be, for example, about a day, a week, a month, or a year or more.
[0184] Rectal Administration
[0185] For compositions adapted for rectal use for preventing disease, a somewhat higher amount of a compound is usually preferred. Thus a dosage of chlorpromazine or a chlorpromazine analog is normally about 5 mg to 2000 mg per dose (preferably about 10 mg to 1000 mg, more preferably about 25 mg to 500 mg) administered one to four times daily. Treatment lengths are as described for oral administration. The dosage of pentamidine or a pentamidine analog is as described for orally administered pentamidine.
[0186] Parenteral Administration
[0187] For intravenous or intramuscular administration of chlorpromazine or a chlorpromazine analog, a dose of about 0.05 mg/kg to about 5 mg/kg body weight per day is recommended, a dose of about 0.05 mg/kg to about 3 mg/kg is preferred, and a dose of 0.01 mg/kg to 2 mg/kg is most preferred. Pentamidine or a pentamidine analog is administered at a daily dose of about 0.05 mg/kg to about 20 mg/kg, preferably at a dose of about 0.05 mg/kg to about 10 mg/kg, and more preferably at a dose of about 0.1 mg/kg to about 4 mg/kg.
[0188] Each compound is usually administered daily for up to about 6 to 12 months or more. It may be desirable to administer a compound over a one to three hour period; this period may be extended to last 24 hours or more. As is described for oral administration, there may be periods of about one day to one year or longer during which at least one of the drugs is not administered.
[0189] Inhalation
[0190] For inhalation, chlorpromazine or a chlorpromazine analog is administered at a dose of about 1 mg to 1000 mg daily, and preferably at a dose of about 2 mg to 500 mg daily. For pentamidine or a pentamidine analog, a dose of about 1 mg to 1000 mg, and preferably at a dose of 2 mg to 600 mg, is administered daily.
[0191] Percutaneous Administration
[0192] For topical administration of either compound or analogs thereof, a dose of about 1 mg to about 5 g administered one to ten times daily for one week to 12 months is usually preferable.
[0193] The following examples are to illustrate the invention. They are not meant to limit the invention in any way.
EXAMPLES
[0194] Chemicals and Drug Preparation
[0195] 5-flurouracil (5-FU), paclitaxel, chlorpromazine and pentamidine were all purchased from Sigma Chemical Co. (St. Louis, Mo.). Chlorpromazine and pentamidine were prepared in phosphate buffered saline (PBS) containing 10% (v/v) EtOH. 5-fluorouracil was initially dissolved in ethanol and diluted in distilled water to a final concentration of 5% (v/v) ethanol. A stock solution of paclitaxel was prepared using a 1:1 (v/v) emulsion of Cremophor EL/ethanol. The paclitaxel stock was diluted 1:6 (v/v) with 0.9M NaCl immediately prior to injection. A combination of chlorpromazine and pentamidine, henceforth referred to as “C/P combination”, was administered as two separate injections..
[0196] Human Tumor Cells.
[0197] The human lung adenocarcinoma tumor cell line, A-549, and human colon cancer cell line, HCT 116, were purchased from American Type Culture Collection (Rockville, Md.). A549 cells were grown in DMEM and HCT 116 cells were grown in McCoy's 5A media, each supplemented with 10% fetal bovine serum (FBS), at 37° C. in a humidified incubator containing 5% CO 2 . Cell cultures were approximately 80% confluent at time of harvest.
[0198] Xenograft Models.
[0199] All experiments were carried out using male or female 6-8 week old SCID Hsd:ICR(CD-1) mice (Harlan, Indianapolis, Ind.). A-549 cells were harvested, resuspended in DMEM minus serum, and injected subcutaneously into the right flanks (4×10 6 cells/flank in a 300 μL volume). HCT 116 cells were harvested, resuspended in McCoy's 5A minus serum, and injected subcutaneously into the right and left flanks (5×10 6 cells/flank in a 300 μL volume). Tumor volumes were determined by measuring the length (l) and the width (w) and calculating the volume (V=lw 2 /2). Depending on the study, the tumors were between about 150 mm 3 -about 800 mm 3 at the time of animal randomization into treatment groups (n=8-10 mice per group).
[0200] Unless otherwise stated, drugs were administered daily Monday to Friday. Paclitaxel was administered 3 days per week, Monday, Wednesday, and Friday only. All drugs were administered by intraperitoneal injection in a volume of 100 μL/25 grams. Animals undergoing combination therapy received two individual injections for a total of 200 μL per mouse. Control animals received 200 μL injections of vehicle only.
[0201] Treatment of mice with C/P combination was generally well tolerated, with no severe adverse events noted. The major side effect observed was sedation, which occurred within 10 minutes of C/P combination or chlorpromazine administration. The sedation was found to last up to 24 hrs in the highest C/P combination doses utilized (10 mg/Kg chlorpromazine, 20 mg/Kg pentamidine). The prolonged sedation seen in the higher doses of C/P combination was accompanied by hypothermia and some bodyweight loss in these animals. Lower doses of either C/P combination or chlorpromazine resulted in a reduced period of sedation and associated hypothermia, increasing animal survival.
[0202] Statistical Analysis.
[0203] Evaluation of the results included statistical analysis of differences in tumor size between test and control groups at the end of each treatment period. Group means were compared using a one-way ANOVA. If the ANOVA was significant, i.e., p<0.05, a Dunnett's multiple comparison test was used to determine which groups were different. Only animals surviving to the completion of the treatment period were included in the analysis.
Example 1
[0204] Dose Optimization of Chlorpromazine/pentamidine in Human Lung Tumor Xenografts.
[0205] Combinations of 10 mg/Kg chlorpromazine and 20 mg/Kg pentamidine or 7.5 mg/Kg chlorpromazine and 20 mg/Kg pentamidine were investigated in a human lung tumor xenograft model. A549 cells were injected subcutaneously into female SCID mice and the tumor volumes were allowed to reach about 400 mm 3 prior to animal randomization. Animals were administered one of the above combinations or saline vehicle control intraperitoneally five times per week (each day, Monday through Friday) for two weeks
[0206] The administration of both 10 mg/Kg chlorpromazine and 7.5 mg/Kg chlorpromazine combinations resulted in substantial reductions of tumor volumes, 56% and 48%, respectively when compared with control. The tumor volume reductions for these combinations were consistently smaller than that observed for the animals treated with high dose, high frequency paclitaxel at a dose of 20 mg/Kg (See Table I). Although tumor growth inhibition was observed with these two combinations, sedation and hypothermia were also evident.
[0207] Using the same protocol as that described above, a combination of 5 mg/Kg chlorpromazine and 20 mg/Kg pentamidine limited the sedation side effects while maintaining anti-tumor activities. In this study, tumor volume was still reduced to 42% of that observed in the vehicle control animals (FIG. 1). Animals treated with paclitaxel (20 mg/Kg) had tumors that were 24% smaller than those observed in vehicle controls and mice receiving chlorpromazine or pentamidine alone exhibited no decrease in tumor volumes compared to control animals.
Example 2
[0208] Effect of Dosing Regimen on Chlorpromazine/pentamidine Activity in Human Lung Tumor Xenografts.
[0209] A multiweek treatment regimen of a combination of 5 mg/Kg chlorpromazine and 20 mg/Kg pentamidine was investigated in a human lung tumor xenograft model. A549 cells were injected subcutaneously into male SCID mice and the tumor volumes were allowed to reach about 400 mm 3 prior to animal randomization. Animals were administered drug combination or vehicle control intraperitoneally five times per week (each day, Monday through Friday) for three weeks. Treatment was stopped for a one week recovery period, then continued as before for an additional two weeks. Results for this multi-week treatment regimen are shown in FIG. 2.
[0210] During the first treatment period, tumor volumes in the chlorpromazine/pentamidine treated animals were consistently smaller then the vehicle control and single agent treated animals. At the end of the first treatment phase, treated tumors were 29% smaller than the control group. After cessation of the first treatment phase, tumors in the treatment group grew at a 37% slower rate compared to the vehicle control during the one week recovery period. On recommencing treatment, only tumor growth in the treatment group was inhibited. At the conclusion of the second treatment period it was observed that, over the course of the entire treatment period, tumor volumes for the chlorpromazine/pentamidine-treated group were reduced by 50% when compared to the vehicle treated animals.
[0211] Paclitaxel (20 mg/Kg) treated animals (not shown in FIG. 2) had tumor volumes that were 27% less than the vehicle control animals at the of the first treatment period, but then had to be sacrificed as a result of cumulative drug toxicity.
TABLE I Summary of C/P Combination Dose Ranging Studies Reduction in Tumor Volume (% decrease relative to control) Combination Tumor Cell Dose Regimen - C/P Dosage Line Combination Combination Positive Control 10 mg/Kg A549 5 days/week 56% 29% Chlorpromazine (M-F) Taxol 20 mg/Kg 20 mg/Kg 2 week treatment (M, W, F) Pentamidine 7.5 mg/Kg A549 5 days/week 48% 24% Chlorpromazine (M-F) Taxol 20 mg/Kg 20 mg/Kg 2 week treatment (M, W, F) Pentamidine 5 mg/Kg A549 5 days/week(M-F) 42% 24% Chlorpromazine 2 week treatment Taxol 20 mg/Kg 20 mg/Kg (M, W, F) Pentamidine 5 mg/Kg A549 5 days/week (M-F) a 29% N/A Chlorpromazine 3 week treatment b 50% Taxol 20 mg/Kg 20 mg/Kg 1 week off treatment (M, W, F) Pentamidine 2 week treatment 5 mg/Kg HCT 116 5 days/week 59% 47% Chlorpromazine (M-F) 5-FU 25 mg/Kg 20 mg/Kg 2 week treatment (M-F) Pentamidine 5 mg/Kg HCT 116 5 days/week 44% N/A Chlorpromazine (M-F) 10 mg/Kg 2 week treatment Pentamidine 5 mg/Kg HCT 116 3 days/week 37% N/A Chlorpromazine (M, W, F) 10 mg/Kg 2 week treatment Pentamidine 2.5 mg/Kg HCT 116 3 days/week 32% N/A Chlorpromazine (M, W, F) 10 mg/Kg 2 week treatment Pentamidine
[0212] All publications and patents cited in this specification are herein incorporated by reference as if each individual publication or patent were specifically and individually indicated to be incorporated by reference. Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the appended claims. | The invention features a method for treating a patient having a cancer or other neoplasm by administering to the patient two compounds simultaneously or within 14 days of each other in amounts sufficient to treat the patient. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. utility patent application Ser. No. 12/029,957, filed on Feb. 12, 2008, which claimed priority to provisional application 60/889,324, filed Feb. 12, 2007, the disclosures of which are incorporated herein by reference.
This application is also related to U.S. utility patent application Ser. No. 12/339,811, filed Mar. 6, 2009; U.S. utility patent application Ser. No. 12/553,808, filed on Sep. 3, 2009, U.S. utility patent application Ser. No. 12/553,823, filed Sep. 3, 2009, U.S. utility patent application Ser. No. 12/584,610; filed Sep. 9, 2009, U.S. utility patent application Ser. No. 12/584,626, filed Sep. 9, 2009, and U.S. utility patent application Ser. No. 12/584,640, filed Sep. 9, 2009.
FIELD OF THE INVENTION
This invention relates in general to an apparatus for converting a natural gas from a feed line to a superheated, clean and dry fuel gas for a gas turbine.
BACKGROUND OF THE INVENTION
Gas turbines are normally supplied with a dry gas that is superheated a selected level above its due point. The super heat avoids any liquids in the gas condensing as the temperature drops.
A typical conditioning system is made up of several pieces of equipment connected together by flowlines. This equipment may include a pre-heater to pre-heat the feed gas flowing into the system. An expansion valve is located in a flowline leading from the pre-heater to a gas scrubber. The expansion valve drops the temperature below the dew point of the gas. Typically, the gas scrubber comprises a cylindrical pressure vessel oriented upright, with the inlet at a lower portion and the outlet at an upper end. A coalescing filter is located between the inlet and the outlet for removing the condensate as the gas flows through. The gas flows then to a super heater, which heats the gas to a desired temperature above the dew point. The gas then flows through another filter to the gas turbine.
While this system works well, it takes up considerable space. Some facilities may lack adequate space. Also, the separate pieces of equipment add to the cost.
SUMMARY
In this invention, a gas conditioning system is provided that is substantially contained within a single pressure vessel. A pre-heater heater element housing is at least partially located within the pressure vessel. The pre-heater heater element housing has an inner passage with an inlet for connection to a source of feed gas and an outlet for delivering the feed gas into the interior of the pressure vessel. At least one electrical heater element is located within the inner passage of the pre-heater heater element housing for increasing the temperature of the feed gas as it flows through the pre-heater heater element housing. An expansion valve reduces the pressure of the feed gas as it flows from the pre-heater heater element housing so as to initiate condensation. A super heater housing is at least partially located within the pressure vessel and has an inlet within the interior of the pressure vessel. The super heater housing has an outlet leading exterior of the pressure vessel. A filter within the interior of the pressure vessel is in a flow path leading from the pre-heater heater element passage housing to the super heater housing for removing condensate from the feed gas. At least one electrical heater element is in the super heater housing for heating the feed gas.
In the preferred embodiment, the pre-heater heater element housing is located within an outer housing, defining an annular passage between the pre-heater heater element housing and the outer housing. The expansion valve is located at a junction between the outlet of the inner passage and an inlet of the annular passage. The expansion valve may be located exterior of the pressure vessel or within the pressure vessel.
The filter is preferably divided into a plurality of segments that are separately removable from the pressure vessel. Each of the segments has an outer edge that comprises a portion of a cylinder and which engages an inner cylindrical wall of the pressure vessel. Each of the segments has an inner edge that abuts an inner edge of another of the segments. Drains lead from the pressure vessel on opposite sides of the filter for draining condensate from the pressure vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sectional view of an apparatus constructed in accordance with this invention.
FIG. 2 is a sectional view of the apparatus of FIG. 1 taken along the line 2 - 2 of FIG. 1 .
FIG. 3 is a sectional view of a portion of an alternate embodiment of an apparatus in accordance with this invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 , fuel gas conditioning system 11 includes a pressure vessel 13 having an interior chamber 12 . Pressure vessel 13 is preferably cylindrical and has two closed ends 14 , 16 . The length of pressure vessel 13 considerably greater than its diameter. In this example, the longitudinal axis of pressure vessel 13 is horizontal.
A pre-heater unit 15 is mounted in pressure vessel 13 with its axis parallel and offset from the longitudinal axis of pressure vessel 13 . Pre-heater unit 15 has a length somewhat greater than the length of pressure vessel 13 in this example, with its ends protruding past ends 14 , 16 of pressure vessel 13 . Pre-heater unit 15 has an outer tubular housing 17 and a concentric inner tubular housing 19 , defining an annulus 21 between housings 17 , 19 . A plurality of electrical heater elements 23 extend longitudinally within inner housing 19 .
Heater elements 23 are conventional elements, each comprising a metal tube containing an electrical resistance wire electrically insulated from the tube. In this embodiment, heater elements 23 are U-shaped, each having its terminal ends mounted within a connector housing 25 located exterior of end 14 of pressure vessel 13 . The bent portions of heater elements 23 are located near the opposite end of pre-heater unit 15 . A power controller 27 supplies power via wires 29 to electrical heater elements 23 . Power controller 27 varies the power in response to temperature sensed by a temperature sensor 31 that is located within chamber 12 in pressure vessel 13 .
Pre-heater unit 15 has an inlet 33 that leads to the interior of inner housing 19 of pre-heater unit 15 in the portion of pre-heater unit 15 exterior of pressure vessel end 14 . In the embodiment of FIG. 1 , an external conduit loop 35 is located on the opposite end of pre-heater unit 15 , exterior of pressure vessel end 16 . External loop 35 leads from the interior of inner housing 19 to annulus 21 . A variable expansion valve 37 is located in external loop 35 for reducing the pressure of the gas flowing through external loop 35 , which also results in cooling of the gas. Expansion valve 37 varies the amount of pressure drop in response to a pressure sensor 39 located within pressure vessel chamber 12 .
Annulus 21 has an outlet 41 located within pressure vessel chamber 12 near end 14 . A mist or coalescing filter 43 is located within pressure vessel chamber 12 approximately halfway between ends 14 , 16 of pressure vessel 13 . Coalescing filter 43 collects liquid mist from the gas flowing from annulus outlet 41 towards the pressure vessel end 16 .
A super-heater 45 is mounted in pressure vessel chamber 12 . Super-heater 45 has an elongated tubular housing 47 that hag an axis parallel with the axis of pre-heater unit 15 and offset from the axis of pressure vessel 13 . Super-heater 45 is located above pre-heater unit 15 in this example and has a length that is less than the length of pre-heater unit 15 . Super-heater 45 has an inlet 49 in housing 47 , inlet 49 being within pressure vessel chamber 12 and closer to pressure vessel end 16 than end 14 . Super-heater 45 has a plurality of electrical resistance heater elements 51 located within housing 47 .
Electrical resistance heater elements 51 may be of the same type as electrical resistance heater elements 23 of pre-heater unit 15 . Preferably, each is U-shaped with both of its terminal ends mounted within an a connector housing 53 , which is external of end 14 of pressure vessel 13 . A power controller 55 supplies power to electrical resistance heater elements 51 . Power controller 55 controls the power in response to temperature sensed by a temperature sensor 57 located within an outlet 59 of super-heater 45 . In this embodiment, outlet 59 leads from a portion of super-heater housing 47 that is external of pressure vessel 13 .
Pressure vessel 13 has at least one drain 61 for draining liquid that condenses within chamber 13 upstream of filter 43 as a result of the pressure drop. A second drain 63 drains liquid that separates from the gas as a result of flowing through filter 43 . Drains 61 , 63 are located on opposite sides of filter 43 and lead downward from a lower point on the sidewall of pressure vessel 13 . Each drain 61 , 63 leads to a separate sump 65 , 66 . In this example, sumps 65 , 66 are compartments of a single tubular pressure vessel and separated from each other by a sealed plate 67 . Outlets 69 , 71 lead from the bottom of sumps 65 , 66 to liquid control valves 73 , 75 . Each liquid control valve 73 , 75 has a level controller 77 , 79 , respectively. Level controllers 77 , 79 are conventional devices to open valves 73 , 75 when the levels of liquid within sumps 65 , 66 reach a selected amount, so as to discharge the liquid from sumps 65 , 66 . Other automatic drain arrangements are feasible.
Pressure vessel 13 has a pressure relief valve 81 in communication with its chamber 12 . Pressure relief valve 81 is a conventional device to relieve pressure in the event that it reaches an excessive amount. Preferably, pressure vessel 13 has an access port 82 with a removable cap. Access port 82 is located in its sidewall in this embodiment. Access port 82 is of a size selected to allow a worker to enter chamber 12 for maintenance, particularly for removing and installing coalescing filter 43 , which must be done periodically.
Referring to FIG. 2 , coalescing filter 43 comprises an assembly of compressible pieces or segments that define an outer diameter that sealingly engages the inner diameter of pressure vessel 13 . The multiple pieces of coalescing filter 43 are sized so that each will pass through access port 82 ( FIG. 1 ). These pieces include in this example a pair of central segments 83 , 85 having inner edges 87 and outer edges 89 that are straight and parallel with each other. Inner edges 87 sealingly abut each other. Each inner edge 87 has a semi-cylindrical recess 91 for engaging super-heater 45 . Each inner edge 87 has a semi-cylindrical recess 93 for fitting around pre-heater unit 15 . Each central segment 83 , 85 has outer diameter portions 95 on opposite ends that are partially cylindrical and sealingly engage the inner diameter of pressure vessel 13 .
Coalescing filter 43 also has two side segments 97 , 99 in this embodiment. Each side segment 97 , 99 has a straight inner edge 101 that abuts one of the outer edges 89 of one of the central segments 83 , 85 . Each side segment 97 has an outer diameter portion 103 that seals against the inner diameter of pressure vessel 13 . Segments 83 , 85 , 97 and 99 are compressible so as to exert retentive forces against each other and against pressure vessel 13 to hold them in place. Retainers (not shown) may also be employed to hold the segments of coalescing filter 43 in position.
Fuel gas conditioning system 11 serves to condition fuel gas for gas turbines. Gas turbines, particularly low pollution types, require a dry feed gas that has a selected amount of superheat, such as 50 degrees above its dew point curve. The term “superheat” is a conventional industry term to refer to a range where the pressure and temperature of the fuel gas are above a range where condensation can occur. Referring to FIG. 1 , feed gas enters inlet 49 at a pressure that may be, for example, 1,000 to 1,300 psig and at a temperature from 60-80 degrees F. The feed gas flows through inner housing 19 of pre-heater unit 15 , which increases the temperature of the feed gas a selected amount over the temperature of the incoming gas. For example, the temperature may be approximately 100-120 degrees F. as it exits inner housing 19 , and the pressure would be approximately the same as at inlet 49 .
This preheated gas then flows through expansion valve 37 , causing a pressure drop to a selected level below the dew point curve, as monitored by pressure sensor 39 . For example, if the intake pressure is 1,000 to 1,300 psig, the pressure may drop to approximately 450-500 psig. The temperature will also drop to perhaps 60-80 degrees F., and at this temperature and pressure, the gas will be below its dew point curve. The lower pressure cooler gas flows back through annulus 21 in pre-heater unit 15 , which adds additional heat. At annulus outlet 41 , the pressure may still be around 450-550 psig and the temperature may be 70-100 degrees F., but still below the dew point. Controller 27 controls the power to heater elements 23 to maintain a desired temperature at outlet 41 as monitored by sensor 31 .
Because the drop in pressure at expansion valve 37 caused the gas to be below its dew point, some of the liquids contained within the gas will condense in chamber 14 upstream of filter 43 . Also, liquids will be separated from the gas by coalescing filter 43 as the gas flows through coalescing filter 43 . The liquids collect on the bottom of pressure vessel 13 and flow through outlets 61 , 63 into sumps 65 , 66 and out through valves 73 , 75 .
After passing through filter 43 , the gas flows toward pressure vessel end 16 and enters inlet 49 of super-heater 45 . Electrical resistance heater elements 51 add heat to the dry gas in an amount that will place the temperature of the gas well above its dew point curve, such as by 50 degrees. The gas, now in a superheated condition, flows out outlet 59 at for example 110-130 degrees F. and 450-550 psig. The gas from outlet 59 flows into a conventional gas turbine (not shown).
FIG. 3 shows a portion of an alternate embodiment wherein pressure vessel 105 contains an expansion valve 107 within its interior. In the first embodiment, expansion valve 37 is located on the exterior of pressure vessel 13 . In FIG. 3 , pre-heater inner housing 109 and outer housing 11 have one end within pressure vessel 105 instead of on the exterior as in the first embodiment. Heater elements 113 are contained within inner housing 109 as in the first embodiment. A valve actuator 115 controls the orifice of expansion valve 107 . Valve actuator 115 varies the pressure drop in response to pressure sensed by a pressure sensor 117 located within the interior of pressure vessel 105 . The second embodiment operates in the same manner as the first embodiment.
The gas conditioner is compact as the components are principally contained within a single pressure vessel. This arrangement reduces the amount of space required and the external flowlines connecting the various components.
While the invention has been shown in only two of its forms, it should be apparent to those skilled in the art that it is not so limited but is susceptible to various changes without departing from the scope of the invention. | A feed gas conditioner includes a pressure vessel that encloses at least part of a pre-heater. The pre-heater has an inlet for connection to a source of feed gas and an outlet for delivering the feed gas into the interior of the pressure vessel. An electrical heater element located within the pre-heater increases the temperature of the feed gas as it flows through the pre-heater. An expansion valve reduces the pressure of the feed gas as it flows from the pre-heater so as to initiate condensation. A super heater is at least partially located within the pressure vessel and has an inlet within the interior of the pressure vessel. A filter is in a flow path in the pressure vessel leading from the pre-heater heater to the super heater for removing condensate from the feed gas. An electrical heater element is in the super heater for heating the feed gas. | 8 |
RELATED APPLICATIONS
[0001] This application claims benefit under 35 USC §119(e) of U.S. provisional patent application no. 61/620,167, filed Apr. 4, 2012, entitled, “Electrodes for Sensing Chemical Composition” the entire disclosure of which is herein incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH & DEVELOPMENT
[0002] Inventions of the present application were made with government support under NIH Grant No. R01 HG006323, awarded by the National Institute of Health. The U.S. Government has certain rights in inventions disclosed herein.
TECHNICAL FIELD
[0003] The subject matter described herein relates to methods, devices, and systems for sequencing nucleic acid polymers.
BACKGROUND
[0004] Nucleic acid bases can be read by using electron tunneling current signals generated as the nucleotides pass through a tunnel gap functionalized with adaptor molecules. For example, PCT publication nos. WO2009/117522A2, WO 2010/042514A1, WO 2009/117517, and WO2008/124706A2, U.S. publication nos. US2010/0084276A1, and US2012/0288948, are all hereby incorporated by reference herein in their entireties. Conventionally, bases have been read using gold electrodes functionalized with adaptor molecules. Carbon nanotubes functionalized with adaptor molecules have also been described for use as electrodes in PCT publication nos. WO2009/117517 and WO 2010/042514A1, and U.S. publication nos. US2011/0168562 and US2011/0120868, which are incorporated herein by reference in their entireties.
[0005] While gold has been found to work well as an electrode material, it suffers from limitations. For examples, it is often incompatible with current technologies used for fabricating electronic devices, owing to its rapid diffusion in silicon and its propensity to form deep level traps, reducing minority carrier lifetime. Second, the tunneling signals generated by the most successful adaptor molecule tried to date, i.e., (4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide), can have a large background generated by water alone. This is illustrated in FIG. 1 , which shows the distribution of signal heights for water alone and the four bases. Current peaks from bases are larger on average, but the distributions are all highly overlapped. There is considerable overlap between the water background and the signals generated by the bases. While the water signals have a time dependence that allows them to be removed from the signal train, this processing is complicated and reduces the accuracy of the reads. Devices that utilize carbon nanotubes functionalized with adaptor molecules to sense chemical compositions can also be difficult to fabricate.
[0006] In view of the foregoing, it would be desirable to provide improved methods, devices, and systems for sequencing nucleic acid polymers. In one aspect according to some embodiments, methods, devices, and systems for sequencing nucleic acid polymers are provided that utilize an electrode material, functionalized with one or more adaptor molecules, that is compatible with semiconductor fabrication processes. In another aspect according to some embodiments, methods, devices, and systems for sequencing nucleic acid polymers are provided that utilize an electrode material, functionalized with one or more adaptor molecules, that is capable of generating signals from DNA nucleobases without interference from water signals. One or both of these improvements and advantages, and/or other improvements and advantages, can be provided in accordance with the present disclosure.
SUMMARY OF SOME OF THE EMBODIMENTS
[0007] Embodiments of the subject matter described herein provide methods, devices, and systems for sequencing nucleic acid polymers.
[0008] For example, some embodiments of the present disclosure provide methods, devices, and systems for sequencing nucleic acid polymers that utilize palladium (Pd), at least in part (e.g., whether it be pure palladium, a palladium alloy, or other composition comprising palladium), as an electrode material that is (i) functionalized with one or more adaptor molecules and (ii) capable for use to sense one or more chemical compositions.
[0009] In some embodiments, a device for identifying a chemical composition (e.g., single molecules) and a corresponding method of fabricating the device are provided. The device includes a first electrode and a second electrode separated from the first electrode by a dielectric material (e.g., dielectric material having about 1 to 5 nm thickness). The first electrode, second electrode, or both have at least one adaptor molecule chemically tethered thereto. In some embodiments, at least one of the first electrode and the second electrode comprises palladium metal (e.g., pure palladium or a palladium alloy). In some embodiments, the adaptor molecule comprises 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide. In some embodiments, the adaptor molecule comprises 4H-1,2,4-triazole-3-carboxamide. In other embodiments, the adaptor molecule comprises 2-(2-carbamoyl-1H-imidazol-4-yl)ethylcarbamodithioate.
[0010] In an embodiment, an apparatus and corresponding method for sensing a chemical composition are provided. For example, in some embodiments, a nucleic acid base is caused to pass through a tunnel gap having electrically-separated electrodes, where at least one of the electrically-separated electrodes comprises palladium metal functionalized with an adaptor molecule. A type of the nucleic acid base is identified based on a tunneling current generated as a result of the nucleic acid base passing through the tunnel gap. In some embodiments, the adaptor molecule comprises 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide. In some embodiments, the adaptor molecule comprises 4H-1,2,4-triazole-3-carboxamide. In other embodiments, the adaptor molecule comprises 2-(2-carbamoyl-1H-imidazol-4-yl)ethylcarbamodithioate.
[0011] In some embodiments, a device for identifying one or more molecules (e.g., single molecules) is provided and comprises a first electrode, a second electrode separated from the first electrode by a dielectric material of about 1 to about 5 nm thickness, at least one adaptor molecule chemically tethered to the first electrode, and at least one adaptor molecule chemically tethered to the second electrode. In some embodiments, at least one of the first electrode and the second electrode comprises palladium metal.
[0012] In some embodiments, both of the first electrode and the second electrode comprise palladium metal. In some embodiments, at least one of the first electrode and the second electrode comprise an alloy of palladium. In some embodiments, at least one adaptor molecule tethered to the first electrode, the at least one adaptor molecule tethered to the second electrode, or both comprise 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide.
[0013] In some embodiments, at least one adaptor molecule tethered to the first electrode, the at least one adaptor molecule tethered to the second electrode, or both comprise 4H-1,2,4-triazole-3-carboxamide.
[0014] In some embodiments, the at least one adaptor molecule tethered to the first electrode, the at least one adaptor molecule tethered to the second electrode, or both comprise 2-(2-carbamoyl-1H-imidazol-4-yl)ethylcarbamodithioate.
[0015] In some embodiments, the electrodes are held under potential control with respect to reference electrode. In some embodiments, the potential of the palladium surface is maintained at between about +0.5V and about −0.5V vs. Ag/AgCl.
[0016] In some embodiments, an apparatus for sensing a chemical composition is provided and may comprise means for causing a nucleic acid base to pass through a tunnel gap having electrically-separated electrodes, where at least one of the electrically-separated electrodes comprises palladium metal functionalized with an adaptor molecule. Such embodiments may also include means for identifying a type of the nucleic acid base based on a tunneling current generated as a result of the nucleic acid base passing through the tunnel gap. Such means may be a computer processor analyzing signal data to determine the identity of the nucleic acid. Such means may also include databases for storing signature signal data for a plurality of molecules to be identified.
[0017] In some embodiments, both of the electrically-separated electrodes comprise palladium metal.
[0018] In some embodiments, at least one of the electrically-separated electrodes comprises an alloy of palladium.
[0019] In some embodiments, the adaptor molecule comprises 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide. In some embodiments, the adaptor molecule comprises 4H-1,2,4-triazole-3-carboxamide, or 2-(2-carbamoyl-1H-imidazol-4-yl)ethylcarbamodithioate.
[0020] In some embodiments, a method of fabricating a device capable of sensing a chemical composition is provided and may comprise one or more of the following steps (and in some embodiments, a plurality, and in some embodiments, all steps): providing a first electrode, providing a second electrode separated from the first electrode by a dielectric material of about 1 to about 5 nm thickness, chemically tethering at least one adaptor molecule to the first electrode, and chemically tethering at least one adaptor molecule to the second electrode. In some embodiments, at least one of the first electrode and the second electrode comprises palladium metal.
[0021] In some embodiments, such methods may also include at least one of chemically tethering at least one adaptor molecule to the first electrode, chemically tethering at least one adaptor molecule to the second electrode, or both, comprises chemically tethering 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide to the first electrode, second electrode, or both.
[0022] In some embodiments, such methods may also include at least one of chemically tethering at least one adaptor molecule to the first electrode, chemically tethering at least one adaptor molecule to the second electrode, or both, comprises chemically tethering 4H-1,2,4-triazole-3-carboxamide to the first electrode, second electrode, or both.
[0023] In some embodiments, such methods may include at least one of chemically tethering at least one adaptor molecule to the first electrode, chemically tethering at least one adaptor molecule to the second electrode, or both, comprises chemically tethering 2-(2-carbamoyl-1H-imidazol-4-yl)ethylcarbamodithioate to the first electrode, second electrode, or both.
[0024] In some embodiments, a method for sensing a chemical composition is provided and may include one or more of the following steps (in some embodiments, a plurality of such steps, and in some embodiments, all of such steps): causing a nucleic acid base to pass through a tunnel gap having electrically-separated electrodes, where at least one of the electrically-separated electrodes comprises palladium, and identifying a type of the nucleic acid base based on the tunneling current generated as a result of the nucleic acid base passing through the tunnel gap. Such identifying may comprise using computers, processors, and the like, to perform steps of analyzing the signal data to eliminate noise and defects, and/or comparing the signal data to signature signal data for a nucleic acid so as to identify the nucleic acid.
[0025] Some embodiments include a computer system for sensing a chemical composition, where the system comprising at least one processor, and where the processor includes computer instructions operating thereon for performing any of the methods taught by the present disclosure.
[0026] In some embodiments, a computer program for sensing a chemical composition is provided and comprises computer instructions for performing any of the methods taught by the present disclosure.
[0027] In some embodiments, a computer readable medium containing a program is provided, where the program includes computer instructions for performing any of the methods taught by the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The accompanying drawings, which are incorporated in and constitute a part of this specification, show certain aspects of the subject matter disclosed herein and, together with the description, help to explain some of the principles associated with the disclosed embodiments. In the drawings:
[0029] FIGS. 1A-F show distributions of pulse heights in tunneling signals generated from: water (A) and the nucleotides dAMP (B), dCMP (C), dCGP (D), dTMP (E) and d 5-methyl CMP (F) using functionalized gold electrodes for sensing chemical compositions. In the figure shown, the set-point tunnel current is 6 pA at 0.5V bias. The large background signals may reflect the presence of contamination, as they are not always so significant. Nonetheless, this background is frequently a problem in conventional systems.
[0030] FIG. 2A shows a schematic diagram of a tunnel gap created using a scanning tunneling microscope according to some embodiments of the present disclosure;
[0031] FIG. 2B shows a device according to some embodiments of the present disclosure fabricated by, for example, drilling a nanopore through two planar electrodes separated by a dielectric layer or other fabrication method;
[0032] FIG. 2C shows an enlarged, cross-sectional view of the nanopore region in FIG. 2B showing how the adaptor molecules span the tunnel gap and are connected to the electrodes on each side of the dielectric layer, according to some embodiments of the disclosure.
[0033] FIG. 3 illustrates a tunnel junction according to some embodiments of the present disclosure and, together with the accompanying text in this disclosure, illustrative fabrication steps for making the tunnel junction according to some embodiments;
[0034] FIG. 4 is a scanning electron microscope (“SEM”) image of a tunnel junction made with palladium (Pd) electrodes separated by a sub 5 nm layer of silicon dioxide (SiO 2 ) according to some embodiments of the present disclosure;
[0035] FIG. 5 is a transmission electron microscope (“TEM”) image of a nanopore drilled through a palladium (Pd) electrode on top of a dielectric support layer according to some embodiments of the present disclosure. In this figure, the atomic lattice of Pd atoms is clearly visible.
[0036] FIG. 6 is a trace diagram of tunnel current versus time for background signal taken in 1 milli-Molar (mM) phosphate buffer using Pd electrodes functionalized with 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide, according to some embodiments of the present disclosure. As shown, there is essentially no background signal at a tunnel conductance of 4 pS (current of 2 pA at 0.5V bias). The current scale is 0 to 80 pA and the time scale is 0.5 s.
[0037] FIG. 7 shows diagrams for typical signal traces for the four nucleotides when such nucleotides were added to a tunnel junction according to some embodiments of the present disclosure. In generating these traces, 100 μM in 1 mM phosphate buffer was used and utilizing Pd electrodes functionalized with 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide at a tunnel conductance of 4 pS (current of 2 pA at 0.5V bias). The current scales are approximately 0 to 80 pA and the time scales 0.3 to 0.5 s.
[0038] FIG. 8 shows diagrams illustrating the distribution of peak heights for the four nucleotides obtained at 4 pS (A) and 8 pS (B) using Pd electrodes functionalized with 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide according to some embodiments of the present disclosure.
[0039] FIG. 9 illustrates the synthesis of the adaptor molecule 4H-1,2,4-triazole-3-carboxamide for use in functionalizing device electrode(s) in accordance with some embodiments of the present disclosure.
[0040] FIG. 10 illustrates the preparation of the adaptor molecule dithiocarbamate derivative of 4(5)-(2-aminoethyl)-1H-imidazole-2-carboxamide for use in functionalizing device electrode(s) in accordance with some embodiments of the present disclosure.
[0041] FIGS. 11A is a graph of the measured tunneling current of 2′-deoxycytidine 5′-monophosphate, according to embodiments of the disclosure;
[0042] FIG. 11B is a graph of the measured tunneling current of 2′-deoxyguanosine 5′-monophosphate, using triazole-3-carboxamide as an adaptor or reading molecule according to some embodiments of the present disclosure.
[0043] FIG. 12 is a graph of the measured tunneling current of 2′-deoxycytidine 5′-monophosphate using imidazole dithiocarbamate as a reading molecule according to some embodiments of the present disclosure.
[0044] FIG. 13 is a graph of the measured tunneling current of 2′-deoxyadenosine 5′-monophosphate using imidazole dithiocarbamate as a reading molecule according to some embodiments of the present disclosure.
[0045] FIG. 14 is a graph of the measured tunneling current of thymidine 5′-monophosphate using imidazole dithiocarbamate as a reading molecule according to some embodiments of the present disclosure.
[0046] FIGS. 15-16 are example computer systems/networks that may be used with devices taught by the present disclosure, and may also be used to perform methods according to any of the methods taught by the present disclosure.
DETAILED DESCRIPTION
[0047] FIGS. 2A-C show illustrative embodiments an electrode system according to some embodiments of the present disclosure. FIG. 2A is representative of some embodiments based on a scanning tunneling microscope platform. A piezoelectric positioner ( 1 ) holds a metal probe ( 2 ) at a distance (d) from a metal substrate ( 3 ). In some embodiments, the metal is palladium, or an alloy of palladium, such as palladium-platinum or palladium-gold. In some embodiments, the distance, d, is set to between 2 and 3 nm by means of the positioner 1 . In some embodiments, the entire arrangement of probe ( 2 ) and substrate ( 3 ) may be immersed in an aqueous electrolyte in which the DNA to be sequenced is dissolved in a single stranded form. In some embodiments, in order to minimize leakage currents the probe ( 2 ) is insulated to within a few microns of its apex with a dielectric material ( 4 ) such as polyethylene. Incorporated herein by reference in its entirety is Tuchband, M., He, J., Huang, S., and Lindsay, S., “Insulated gold scanning tunneling microscopy probes for recognition tunneling in an aqueous environment,” Rev, Sci. Instrum. 2012, 83, 015102.
[0048] Still referring to FIG. 2A , in some embodiments, the DNA is passed into the tunnel junction by electrophoretic transport through a nanopore drilled or otherwise formed through the substrate in close proximity to the tunnel junction ( 5 ). The aqueous electrolyte may be phosphate buffer with a concentration in the range of 1 to 100 mM, adjusted to pH 7.0, or other suitable aqueous electrolyte. A voltage bias V ( 6 ) may be applied across the tunnel junction, and the current, I, through the junction measured with a transconductance amplifier ( 7 ). Importantly, the electrodes are functionalized with one or more adaptor molecules ( 8 ). These are molecule(s) that form non-covalent bonds with DNA bases but are bonded (e.g., strongly bonded) to the metal electrodes, for example, via thiol linkages. In one embodiment, the adaptor molecule(s) tethered to the first and/or second electrodes is 4(5)-(2-mercaptoethyl)-1H-imidazole-2-carboxamide. Alternatively or in addition, other types of adaptor molecules may be tethered to the electrodes, for example, as described below in connection with FIGS. 9-14 . DNA bases passing through the tunnel gap generate stochastic tunneling signals that can be used to identify the base in the tunnel gap.
[0049] FIGS. 2B and 2C show an electrode configuration for sensing according to some embodiments of the present disclosure. A first metal electrode ( 10 ) opposes a second metal electrode ( 11 ) spaced by a dielectric material (e.g., layer) ( 12 ). In some embodiments, the spacing is between 2 and 3 nm. Suitable dielectrics according to some embodiments include aluminum oxide, other metal oxides such a hafnium oxide, silicon dioxide, silicon nitride, or combinations thereof In some embodiments, one or both of electrodes 10 and 11 include palladium (e.g., pure palladium or a palladium alloy). In some embodiments, the electrodes include, or consist of, palladium (e.g., approximately 9 nm of Pd) on top of a titanium (Ti) adhesion layer (e.g., approximately 1 nm thick Ti adhesion layer). A nanopore ( 13 ) is drilled or otherwise formed through the two electrodes using, for example, an electron beam. FIG. 2C is an enlargement showing the electrodes ( 10 , 11 ) and nanopore ( 13 ). In some embodiments, diameter of the nanopore is between approximately 1.5 and 5 nm. In some embodiments, the metal electrodes are functionalized with adaptor molecules ( 8 ), including, for example, one or more of the adaptor molecules described above and in connection with FIGS. 9-14 .
[0050] FIG. 3 is a schematic diagram of a device according to some embodiments of the present disclosure. A silicon (Si) substrate ( 101 ) has insulating layers ( 102 and 103 ) such as silicon nitride (Si 3 N 4 ) deposited on the front and back sides of the substrate ( 101 ). A window is opened on the backside through layer ( 103 ) via, for example, photolithography and reactive ion etching, and a through-substrate-via is etched from this window and ends on ( 102 ) to form a free-standing insulating membrane ( 109 ), for example, using wet etchant such as KOH or TMAH. An electrode (e.g., Pd or Pd alloy) layer ( 104 ) is deposited on top of insulating layer ( 102 ) and is then patterned, for example, via photolithography and metal lift-off processing. An insulating layer ( 105 ) is then deposited on top of the electrode layer ( 104 ). Another electrode (e.g., Pd or Pd alloy) layer ( 106 ) is deposited on top of ( 105 ) and patterned, for example, via photolithography and metal lift-off processing. The front side may be capsulated by an insulating layer ( 107 ). Via holes () and ( 111 ) are etched through insulating layers ( 107 ) and/or ( 105 ) to allow access to the metal electrode layers ( 104 ) and ( 106 ). In this way, two electrically addressable separated circular electrodes (e.g. Pd or Pd alloy electrodes) are made inside the nanopore for tunneling current measurements.
[0051] FIG. 4 is an SEM image of device fabricated as described above, but prior to forming (e.g., in this instance, drilling) of the nanopore. FIG. 5 is a high resolution TEM image of a nanopore drilled through a Pd electrode. The atomic structure of the Pd layer is clearly visible. These data demonstrate that fabrication of an electrode system compatible with silicon manufacturing processes has been achieved.
[0052] Another advantage of probes that include palladium (e.g., pure Pd or Pd alloy) lies with their ability to generate reads from DNA bases at a setpoint conductance that is much smaller than was used for gold electrodes with the 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide adaptor molecules. By way of illustration in accordance with some embodiments, and as shown below, reliable signals are obtained with a tunnel gap of 4 pS conductance, well below the 12 pS that had to be used to acquire the data taken with gold electrodes ( FIG. 1 ). At 4 ps there were essentially no background signals at all when data was recorded in Phosphate Buffered Saline (PBS) buffer containing no nucleotides. An illustrative trace of tunnel current vs. time is shown in FIG. 6 .
[0053] These same conditions also produced copious amounts of signal when nucleotides were added to the tunnel junction. FIG. 7 shows typical signal traces for some embodiments of the present disclosure for the four nucleotides at a background current of 2 pA with a bias of 0.5V (note that the scale on the plots shows the baseline tunnel current at or below 0 pA—this was a consequence of a small offset in the data acquisition system). As shown, the signals are large—in the range of 20 to 50 pS. In contrast, with conventional gold electrodes, no signals are generated at 4 pS conductance.
[0054] Operation at this low tunnel conductance provides excellent separation of the signals from the bases. FIG. 8 shows (A) the distribution of peak heights for all 4 nucleotides obtained at a tunnel conductance of 4 pS and (B) at 8 pS. As shown, the distributions are clearly better separated at 4 pS. The findings described herein that Pd produces such superior results when used for the functionalized electrode(s) within a device for sensing chemical compositions (e.g., instead to gold electrodes) was both surprising and unexpected. Lawson, J. W. and Bauschlicher, C. W., “Transport in Molecular Junctions with different molecular contacts,” Physical Review B 2006, 74, 125401, which is incorporated herein by reference in its entirety, includes a theoretical consideration of the tunneling currents that would be provided through a molecular junction by Ag, Au, Pd and Pt. Theoretical calculations were carried out for a phenoldithiol molecule directly bridging a pair of metal electrodes with one sulfur attached to one electrode and the other attached to the second electrode. These calculations showed that Pd electrodes might produce more current than Au electrodes in this case. However, there have been no calculations for the non-covalently-bonded complexes used in recognition tunneling so the effect of changing the metal electrode in that case is unknown.
[0055] The device configurations described above in connection with FIGS. 2-8 are only illustrative. Any other suitable configurations of a device for sensing chemical composition may be used, including with respect to device geometry (e.g., positioning, thickness, length, and width of the electrode(s) and/or dielectric(s)), materials selected for the metal(s) and/or dielectric(s), or both.
[0056] In various embodiments of the present disclosure, any suitable adaptor molecule(s) can be tethered to the first and/or second electrodes of a device as reading molecules for recognition tunneling. In some embodiments, the adaptor molecule is 4(5)-(2-mercaptoethyl)-1H imidazole-2-carboxamide. In some embodiments, the adaptor molecule is 4H-1,2,4-triazole-3-carboxamide. In some embodiments, the adaptor molecule is 2-(2-carbamoyl-1H-imidazol-4-yl)ethylcarbamodithioate.
[0057] Synthesis of the 5-substituted-4H-1,2,4-triazole-3-carboxamide molecule just described is described as follows and in connection with FIG. 9 . With reference to FIG. 9 , synthesis of ( 6 ) was accomplished as follows: sodium hydride (60% in mineral oil, 1.16 g, 24.0 mmol) was added to a solution of benzyl mercaptan ( 4 ) (1.05 g, 19.0 mmol) in anhydrous DMF (50 mL) at 0° C. under nitrogen atmosphere. The resulting mixture was stirred for 30 min at 0° C., followed by the dropwise addition of 3-bromopropanenitrile ( 5 ) (2.68 g, 20.0 mmol). The reaction mixture was stirred at 0° C. for 1 h and then allowed to warm to room temperature and stirred overnight to consume starting material completely. The reaction was stopped. The solvent was removed by rotary evaporation under reduced pressure followed by the addition of saturated aqueous NH 4 Cl solution to quench and the solvent was removed by rotary evaporation under reduced pressure. The residuum was extracted with chloroform (3×20 mL). The combined organic layer was washed with water (3×10 mL), brine (30 mL) and concentrated under reduced pressure. The crude product was purified by silica gel flash column chromatography. Product ( 6 ) obtained (2.25 g, 65%) was pale yellow in color. The product was characterized and confirmed by NMR and mass spectrometry.
[0058] Still referring to FIG. 9 , synthesis of ( 7 ) was accomplished as follows: compound ( 6 ) (2.0 g, 11.3 mmol) and benzyl mercaptan ( 4 ) (2.0 mL, 16.93 mmol) were sequentially added in anhydrous ethyl ether (120 mL) under nitrogen. The resulting solution was cooled to 0° C. and HCl (g, anhydrous) was bubbled for 2 hours (h) until it was saturated with hydrogen chloride. It was stirred for 24 h at room temperature. The product was spontaneously crystallized in the solution. It was collected on a filter paper by filtration through a Buchner funnel, washed with cold ethyl ether (50 mL), and dried in air then in vacuum. Product ( 7 ) was obtained in high yield (3.7 g, 97%). The product was characterized and confirmed by NMR and mass spectrometry.
[0059] With further reference to FIG. 9 , synthesis of ( 3 ) was accomplished as follows: oxamic acid hydrazide ( 8 ) (0.34 g, 3.32 mmol) was added into a solution of compound ( 7 ) (1.0 g, 3.32 mmol) in anhydrous pyridine (10 mL) at room temperature under nitrogen. The resulting solution was refluxed at 110° C. for 3 h. Pyridine was co-evaporated with toluene (5 mL*2) under reduced pressure to obtain a yellow gummy liquid. DMSO (15 mL) was added to just dissolve the crude product and sufficient water (50 mL) was added to get white precipitate, which was filtered through a Buchner funnel and washed thoroughly with cold water (40 mL) followed by ethyl ether (40 mL). The solid was air-dried to obtain 0.53 g of the crude product, which was recrystallized from boiling ethanol (25 mL) to furnish 0.31 g (40%) of pure product ( 3 ) as white shiny crystals. The product was characterized and confirmed by NMR and mass spectrometry.
[0060] Still referring to FIG. 9 , synthesis of ( 1 ) was accomplished as follows: compound ( 3 ) (150 mg, 0.572 mmol) was suspended in 2 mL of liquid NH 3 . Freshly cut sodium was added till a permanent blue color was observed and stirred the reaction mixture for 1.5 h at −78° C. The reaction was quenched by addition of NH 4 Cl and NH 3 was evaporated at room temperature. Column purification gave 98 mg of the product ( 1 ) (31%). The product was characterized by NMR and MALDI mass. Although the product is sensitive to air and readily oxidized to give disulfide or sulfone products, it was stored at 0° C. in its solid state with a good stability for few months.
[0061] Preparation of the dithiocarbamate derivative of 4(5)-(2-aminoethyl)-1H-imidazole-2-carboxamide described above, for example, for use as a reading molecule for recognition tunneling is described as follows and in connection with FIG. 10 . This is the same adaptor molecule 2-(2-carbamoyl-1H-imidazol-4-yl)ethylcarbamodithioate described above. With reference to FIG. 10 , 4(5)-(2-aminoethyl)-1H-imidazole-2-carboxamide (77 mg, 0.32 mmol) and CS 2 (24 ul, 0.38 mmol) were dissolved in triethylamine (1.4 ml, 9.7 mmol). The mixture was stirred at room temperature for 24 h. The precipitate was filtered and washed with ethyl ether (5 ml×3) and dried in vacuum, giving the product with a near quantitative yield.
[0062] Tunneling measurements were taken using the adaptor molecules described in connection with FIGS. 9 and 10 . In each instance, both palladium substrates and palladium tips were used for the measurements. Newly etched palladium tips were coated with high density polyethylene, rinsed with ethanol; the palladium substrates were annealed with hydrogen flame. Both palladium substrates and tips were immersed in a 1 mM solution of read molecule for about 24 hours, then rinsed copiously with ethanol and blow-dried with nitrogen. Tunneling measurements were performed in an Agilent PicoSPM instrument with self-made Labview software. This software collects trains of current vs. time data from a digital oscilloscope connected to the tunnel junction and presents it in graphical form where amplitude and other aspects of the spikes in tunnel current can be measured. PBS buffer (1 mM, 7.4 pH) was used for control tunneling measurements and 10 μM solution (in 1 mM, 7.4 pH PBS buffer) of nucleoside monophosphates were used for recognition measurements. Before recording the tunneling data, the system was left in an environmental chamber for more than 3 hours to be stabilized without any bias applied between the substrate and the tip. After the system was stabilized, different bias and setpoint was added between the substrate and the tip and the tunneling signal was collected.
[0063] FIG. 11 shows the tunneling measurements with the triazole-carboxamide adaptor molecule. The tunneling currents were measured at a set point of −0.5 v, 4 pA using a Pd probe and Pd substrate.
[0064] FIGS. 12-14 show the tunneling measurements with the imidazole dithiocarbamate adaptor molecule. The tunneling currents were measured at a set point of −0.5 v, 2 pA using a Pd probe and Pd substrate.
[0065] In some embodiments of the present disclosure, palladium electrodes may catalyze a number of chemical reactions. For example, and in particular, in some embodiments, cyclic voltammetry shows that phosphate is strongly adsorbed on the electrodes. Such an effect, in some embodiments, becomes more pronounced upon the potential of the palladium exceeding, for example, about +0.5V (adsorption). In addition, in some embodiments, such an effect becomes less pronounced (i.e., more negative) than about −0.5V (desorption) with respect to an Ag/AgCl reference electrode. Thus, in some embodiments, it may be advantageous to retain the palladium electrodes within such a range of potentials with respect to a reference electrode (for example). In some embodiments, the most negative electrode of the pair may be held more positive than about −0.5V vs. Ag/AgCl and the most positive of the pair, in some embodiments, may be held more negative than about +0.5V vs. Ag/AgCl.
[0066] Various implementations of the embodiments disclosed above, in particular at least some of the methods/processes disclosed, may be realized in digital electronic circuitry, integrated circuitry, specially designed ASICs (application specific integrated circuits), computer hardware, firmware, software, and/or combinations thereof. These various implementations may include implementation in one or more computer programs that are executable and/or interpretable on a programmable system including at least one programmable processor, which may be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.
[0067] Such computer programs (also known as programs, software, software applications or code) include machine instructions for a programmable processor, for example, and may be implemented in a high-level procedural and/or object-oriented programming language, and/or in assembly/machine language. As used herein, the term “machine-readable medium” refers to any computer program product, apparatus and/or device (e.g., magnetic discs, optical disks, memory, Programmable Logic Devices (PLDs)) used to provide machine instructions and/or data to a programmable processor, including a machine-readable medium that receives machine instructions as a machine-readable signal. The term “machine-readable signal” refers to any signal used to provide machine instructions and/or data to a programmable processor.
[0068] To provide for interaction with a user, some of the subject matter described herein may be implemented on a computer having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor and the like) for displaying information to the user and a keyboard and/or a pointing device (e.g., a mouse or a trackball) by which the user may provide input to the computer. For example, this program can be stored, executed and operated by the dispensing unit, remote control, PC, laptop, smart-phone, media player or personal data assistant (“PDA”). Other kinds of devices may be used to provide for interaction with a user as well; for example, feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including acoustic, speech, or tactile input.
[0069] Certain embodiments of the subject matter described herein may be implemented in a computing system and/or devices that includes a back-end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front-end component (e.g., a client computer having a graphical user interface or a Web browser through which a user may interact with an implementation of the subject matter described herein), or any combination of such back-end, middleware, or front-end components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local area network (“LAN”), a wide area network (“WAN”), and the Internet.
[0070] The computing system according to some such embodiments described above may include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.
[0071] For example, as shown in FIG. 15 at least one processor which may include instructions operating thereon for carrying out one and/or another disclosed method, which may communicate with one or more databases and/or memory—of which, may store data required for different embodiments of the disclosure. As noted, the processor may include computer instructions operating thereon for accomplishing any and all of the methods and processes disclosed in the present disclosure. Input/output means may also be included, and can be any such input/output means known in the art (e.g., display, printer, keyboard, microphone, speaker, transceiver, and the like). Moreover, in some embodiments, the processor and at least the database can be contained in a personal computer or client computer which may operate and/or collect data. The processor also may communicate with other computers via a network (e.g., intranet, internet).
[0072] Similarly, FIG. 16 illustrates a system according to some embodiments which may be established as a server-client based system, in which the client computers are in communication with databases, and the like. The client computers may communicate with the server via a network (e.g., intranet, internet, VPN).
[0073] Any and all references to publications or other documents, including but not limited to, patents, patent applications, articles, webpages, books, etc., presented in the present application, are herein incorporated by reference in their entirety.
[0074] Although a few variations have been described in detail above, other modifications are possible. For example, any logic flow depicted in the accompanying figures and described herein does not require the particular order shown, or sequential order, to achieve desirable results. Other implementations may be within the scope of at least some of the following claims.
[0075] Example embodiments of the devices, systems and methods have been described herein. As noted elsewhere, these embodiments have been described for illustrative purposes only and are not limiting. Other embodiments are possible and are covered by the disclosure, which will be apparent from the teachings contained herein. Thus, the breadth and scope of the disclosure should not be limited by any of the above-described embodiments but should be defined only in accordance with claims supported by the present disclosure and their equivalents. Moreover, embodiments of the subject disclosure may include methods, systems and devices which may further include any and all elements from any other disclosed methods, systems, and devices, including any and all elements corresponding to methods, systems and devices for sensing chemical composition. In other words, elements from one or another disclosed embodiments may be interchangeable with elements from other disclosed embodiments. In addition, one or more features/elements of disclosed embodiments may be removed and still result in patentable subject matter (and thus, resulting in yet more embodiments of the subject disclosure). | Some embodiments of the present disclosure provide methods, devices, and systems for sequencing nucleic acid polymers that utilize palladium (Pd), for example, at least in part, as an electrode material that is (i) functionalized with one or more adaptor molecules and (ii) capable for use to sense one or more chemical compositions. | 8 |
This application is a continuation of U.S. patent application Ser. No. 10/766,149, entitled “Delivery of Sedative-Hypnotics Through an Inhalation Route,” filed Jan. 27, 2004, Rabinowitz and Zaffaroni; which is a continuation of U.S. Pat. Nos. 6,716,415 and 7,078,017, entitled “Delivery of Sedative-Hypnotics Through an Inhalation Route,” filed May 17, 2002 and Dec. 30, 2003, respectively, Rabinowitz and Zaffaroni, which claim priority to U.S. provisional application Ser. No. 60/294,203 entitled “Thermal Vapor Delivery of Drugs,” filed May 24, 2001, Rabinowitz and Zaffaroni and to U.S. provisional application Ser. No. 60/317,479 entitled “Aerosol Drug Delivery,” filed Sep. 5, 2001, Rabinowitz and Zaffaroni, the entire disclosures of which are hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to the delivery of sedative-hypnotics through an inhalation route. Specifically, it relates to aerosols containing sedative-hypnotics that are used in inhalation therapy.
BACKGROUND OF THE INVENTION
There are a number of compositions currently marketed as sedative-hypnotics. The compositions contain at least one active ingredient that provides for observed therapeutic effects. Among the active ingredients given in sedative-hypnotic compositions are zolpidem, zaleplon, and zopiclone.
It is desirable to provide a new route of administration for sedative-hypnotics that rapidly produces peak plasma concentrations of the compound. The provision of such a route is an object of the present invention.
SUMMARY OF THE INVENTION
The present invention relates to the delivery of sedative-hypnotics through an inhalation route. Specifically, it relates to aerosols containing sedative-hypnotics that are used in inhalation therapy.
In a composition aspect of the present invention, the aerosol comprises particles comprising at least 5 percent by weight of a sedative-hypnotic. Preferably, the particles comprise at least 10 percent by weight of a sedative hypnotic. More preferably, the particles comprise at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent or 99.97 percent by weight of a sedative hypnotic.
Typically, the aerosol has a mass of at least 10 μg. Preferably, the aerosol has a mass of at least 100 μg. More preferably, the aerosol has a mass of at least 200 μg.
Typically, the particles comprise less than 10 percent by weight of sedative-hypnotic degradation products. Preferably, the particles comprise less than 5 percent by weight of sedative-hypnotic degradation products. More preferably, the particles comprise less than 2.5, 1, 0.5, 0.1 or 0.03 percent by weight of sedative-hypnotic degradation products.
Typically, the particles comprise less than 90 percent by weight of water. Preferably, the particles comprise less than 80 percent by weight of water. More preferably, the particles comprise less than 70 percent, 60 percent, 50 percent, 40 percent, 30 percent, 20 percent, 10 percent, or 5 percent by weight of water.
Typically, at least 50 percent by weight of the aerosol is amorphous in form, wherein crystalline forms make up less than 50 percent by weight of the total aerosol weight, regardless of the nature of individual particles. Preferably, at least 75 percent by weight of the aerosol is amorphous in form. More preferably, at least 90 percent by weight of the aerosol is amorphous in form.
Typically, the aerosol has an inhalable aerosol particle density greater than 10 6 particles/mL. Preferably, the aerosol has an inhalable aerosol particle density greater than 10 7 particles/mL or 10 8 particles/mL.
Typically, the aerosol particles have a mass median aerodynamic diameter of less than 5 microns, e.g., 0.2 to 3 microns. Preferably, the particles have a mass median aerodynamic diameter of less than 3 microns. More preferably, the particles have a mass median aerodynamic diameter of less than 2 or 1 micron(s).
Typically, the geometric standard deviation around the mass median aerodynamic diameter of the aerosol particles is less than 3.0. Preferably, the geometric standard deviation is less than 2.5. More preferably, the geometric standard deviation is less than 2.2.
Typically, the aerosol is formed by heating a composition containing a sedative-hypnotic to form a vapor and subsequently allowing the vapor to condense into an aerosol.
In another composition aspect of the present invention, the aerosol comprises particles comprising at least 5 percent by weight of zaleplon, zolpidem or zopiclone. Preferably, the particles comprise at least 10 percent by weight of zaleplon, zolpidem or zopiclone. More preferably, the particles comprise at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent or 99.97 percent by weight of zaleplon, zolpidem or zopiclone.
Typically, the aerosol has a mass of at least 10 μg. Preferably, the aerosol has a mass of at least 100 μg. More preferably, the aerosol has a mass of at least 200 μg.
Typically, the particles comprise less than 10 percent by weight of zaleplon, zolpidem or zopiclone degradation products. Preferably, the particles comprise less than 5 percent by weight of zaleplon, zolpidem or zopiclone degradation products. More preferably, the particles comprise less than 2.5, 1, 0.5, 0.1 or 0.03 percent by weight of zaleplon, zolpidem or zopiclone degradation products.
Typically, the particles comprise less than 90 percent by weight of water. Preferably, the particles comprise less than 80 percent by weight of water. More preferably, the particles comprise less than 70 percent, 60 percent, 50 percent, 40 percent, 30 percent, 20 percent, 10 percent, or 5 percent by weight of water.
Typically, at least 50 percent by weight of the aerosol is amorphous in form, wherein crystalline forms make up less than 50 percent by weight of the total aerosol weight, regardless of the nature of individual particles. Preferably, at least 75 percent by weight of the aerosol is amorphous in form. More preferably, at least 90 percent by weight of the aerosol is amorphous in form.
Typically, the aerosol has an inhalable aerosol drug mass density of between 0.5 mg/L and 40 mg/L. Preferably, the aerosol has an inhalable aerosol drug mass density of between 1 mg/L and 20 mg/L. More preferably, the aerosol has an inhalable aerosol drug mass density of between 1 mg/L and 10 mg/L.
Typically, the aerosol has an inhalable aerosol particle density greater than 10 6 particles/mL. Preferably, the aerosol has an inhalable aerosol particle density greater than 10 7 particles/mL or 10 8 particles/mL.
Typically, the aerosol particles have a mass median aerodynamic diameter of less than 5 microns, e.g., 0.2 to 3 microns. Preferably, the particles have a mass median aerodynamic diameter of less than 3 microns. More preferably, the particles have a mass median aerodynamic diameter of less than 2 or 1 micron(s).
Typically, the geometric standard deviation around the mass median aerodynamic diameter of the aerosol particles is less than 3.0. Preferably, the geometric standard deviation is less than 2.5. More preferably, the geometric standard deviation is less than 2.2.
Typically, the aerosol is formed by heating a composition containing zaleplon, zolpidem or zopiclone to form a vapor and subsequently allowing the vapor to condense into an aerosol.
In a method aspect of the present invention, one of a sedative-hypnotic is delivered to a mammal through an inhalation route. The method comprises: a) heating a composition, wherein the composition comprises at least 5 percent by weight of a sedative-hypnotic, to form a vapor; and, b) allowing the vapor to cool, thereby forming a condensation aerosol comprising particles, which is inhaled by the mammal. Preferably, the composition that is heated comprises at least 10 percent by weight of a sedative-hypnotic. More preferably, the composition comprises at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent, 99.9 percent or 99.97 percent by weight of a sedative-hypnotic.
Typically, the particles comprise at least 5 percent by weight of a sedative-hypnotic. Preferably, the particles comprise at least 10 percent by weight of a sedative-hypnotic. More preferably, the particles comprise at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent, 99.9 percent or 99.97 percent by weight of a sedative-hypnotic.
Typically, the condensation aerosol has a mass of at least 10 μg. Preferably, the aerosol has a mass of at least 100 μg. More preferably, the aerosol has a mass of at least 200 μg.
Typically, the particles comprise less than 10 percent by weight of sedative-hypnotic degradation products. Preferably, the particles comprise less than 5 percent by weight of sedative-hypnotic degradation products. More preferably, the particles comprise 2.5, 1, 0.5, 0.1 or 0.03 percent by weight of sedative-hypnotic degradation products.
Typically, the particles comprise less than 90 percent by weight of water. Preferably, the particles comprise less than 80 percent by weight of water. More preferably, the particles comprise less than 70 percent, 60 percent, 50 percent, 40 percent, 30 percent, 20 percent, 10 percent, or 5 percent by weight of water.
Typically, at least 50 percent by weight of the aerosol is amorphous in form, wherein crystalline forms make up less than 50 percent by weight of the total aerosol weight, regardless of the nature of individual particles. Preferably, at least 75 percent by weight of the aerosol is amorphous in form. More preferably, at least 90 percent by weight of the aerosol is amorphous in form.
Typically, the particles of the delivered condensation aerosol have a mass median aerodynamic diameter of less than 5 microns, e.g., 0.2 to 3 microns. Preferably, the particles have a mass median aerodynamic diameter of less than 3 microns. More preferably, the particles have a mass median aerodynamic diameter of less than 2 or 1 micron(s).
Typically, the geometric standard deviation around the mass median aerodynamic diameter of the aerosol particles is less than 3.0. Preferably, the geometric standard deviation is less than 2.5. More preferably, the geometric standard deviation is less than 2.2.
Typically, the delivered aerosol has an inhalable aerosol particle density greater than 10 6 particles/mL. Preferably, the aerosol has an inhalable aerosol particle density greater than 10 7 particles/mL or 10 8 particles/mL.
Typically, the rate of inhalable aerosol particle formation of the delivered condensation aerosol is greater than 10 8 particles per second. Preferably, the aerosol is formed at a rate greater than 10 9 inhaleable particles per second. More preferably, the aerosol is formed at a rate greater than 10 10 inhaleable particles per second.
Typically, the delivered condensation aerosol is formed at a rate greater than 0.5 mg/second. Preferably, the aerosol is formed at a rate greater than 0.75 mg/second. More preferably, the aerosol is formed at a rate greater than 1 mg/second, 1.5 mg/second or 2 mg/second.
Typically, the delivered condensation aerosol results in a peak plasma concentration of a sedative-hypnotic in the mammal in less than 1 h. Preferably, the peak plasma concentration is reached in less than 0.5 h. More preferably, the peak plasma concentration is reached in less than 0.2, 0.1, 0.05, 0.02, 0.01, or 0.005 h (arterial measurement).
Typically, the delivered condensation aerosol is used to treat insomnia.
In another method aspect of the present invention, one of zaleplon, zolpidem or zopiclone is delivered to a mammal through an inhalation route. The method comprises: a) heating a composition, wherein the composition comprises at least 5 percent by weight of zaleplon, zolpidem or zopiclone, to form a vapor; and, b) allowing the vapor to cool, thereby forming a condensation aerosol comprising particles, which is inhaled by the mammal. Preferably, the composition that is heated comprises at least 10 percent by weight of zaleplon, zolpidem or zopiclone. More preferably, the composition comprises at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent, 99.9 percent or 99.97 percent by weight of zaleplon, zolpidem or zopiclone.
Typically, the particles comprise at least 5 percent by weight of zaleplon, zolpidem or zopiclone. Preferably, the particles comprise at least 10 percent by weight of zaleplon, zolpidem or zopiclone. More preferably, the particles comprise at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent, 99.9 percent or 99.97 percent by weight of zaleplon, zolpidem or zopiclone.
Typically, the condensation aerosol has a mass of at least 10 μg. Preferably, the aerosol has a mass of at least 100 μg. More preferably, the aerosol has a mass of at least 200 μg.
Typically, the particles comprise less than 10 percent by weight of zaleplon, zolpidem or zopiclone degradation products. Preferably, the particles comprise less than 5 percent by weight of zaleplon, zolpidem or zopiclone degradation products. More preferably, the particles comprise 2.5, 1, 0.5, 0.1 or 0.03 percent by weight of zaleplon, zolpidem or zopiclone degradation products.
Typically, the particles comprise less than 90 percent by weight of water. Preferably, the particles comprise less than 80 percent by weight of water. More preferably, the particles comprise less than 70 percent, 60 percent, 50 percent, 40 percent, 30 percent, 20 percent, 10 percent, or 5 percent by weight of water.
Typically, at least 50 percent by weight of the aerosol is amorphous in form, wherein crystalline forms make up less than 50 percent by weight of the total aerosol weight, regardless of the nature of individual particles. Preferably, at least 75 percent by weight of the aerosol is amorphous in form. More preferably, at least 90 percent by weight of the aerosol is amorphous in form.
Typically, the particles of the delivered condensation aerosol have a mass median aerodynamic diameter of less than 5 microns, e.g., 0.2 to 3 microns. Preferably, the particles have a mass median aerodynamic diameter of less than 3 microns. More preferably, the particles have a mass median aerodynamic diameter of less than 2 or 1 micron(s).
Typically, the geometric standard deviation around the mass median aerodynamic diameter of the aerosol particles is less than 3.0. Preferably, the geometric standard deviation is less than 2.5. More preferably, the geometric standard deviation is less than 2.2.
Typically, the delivered aerosol has an inhalable aerosol drug mass density of between 0.5 mg/L and 40 mg/L. Preferably, the aerosol has an inhalable aerosol drug mass density of between 1 mg/L and 20 mg/L. More preferably, the aerosol has an inhalable aerosol drug mass density of between 1 mg/L and 10 mg/L.
More preferably, the aerosol has an inhalable aerosol drug mass density of between 1.5 mg/L and 7.5 mg/L.
Typically, the delivered aerosol has an inhalable aerosol particle density greater than 10 6 particles/mL. Preferably, the aerosol has an inhalable aerosol particle density greater than 10 7 particles/mL or 10 8 particles/mL.
Typically, the rate of inhalable aerosol particle formation of the delivered condensation aerosol is greater than 10 8 particles per second. Preferably, the aerosol is formed at a rate greater than 10 9 inhaleable particles per second. More preferably, the aerosol is formed at a rate greater than 10 10 inhaleable particles per second.
Typically, the delivered condensation aerosol is formed at a rate greater than 0.5 mg/second. Preferably, the aerosol is formed at a rate greater than 0.75 mg/second. More preferably, the aerosol is formed at a rate greater than 1 mg/second, 1.5 mg/second or 2 mg/second.
Typically, between 0.5 mg and 40 mg of drug are delivered to the mammal in a single inspiration. Preferably, between 1 mg and 20 mg of drug are delivered to the mammal in a single inspiration. More preferably, between 1 mg and 10 mg of drug are delivered to the mammal in a single inspiration.
Typically, the delivered condensation aerosol results in a peak plasma concentration of zaleplon, zolpidem or zopiclone in the mammal in less than 1 h. Preferably, the peak plasma concentration is reached in less than 0.5 h. More preferably, the peak plasma concentration is reached in less than 0.2, 0.1, 0.05, 0.02, 0.01, or 0.005 h (arterial measurement).
Typically, the delivered condensation aerosol is used to treat insomnia.
In a kit aspect of the present invention, a kit for delivering a sedative-hypnotic through an inhalation route to a mammal is provided which comprises: a) a composition comprising at least 5 percent by weight of a sedative-hypnotic; and, b) a device that forms a sedative-hypnotic aerosol from the composition, for inhalation by the mammal. Preferably, the composition comprises at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent, 99.9 percent or 99.97 percent by weight of a sedative-hypnotic.
Typically, the device contained in the kit comprises: a) an element for heating the sedative-hypnotic composition to form a vapor; b) an element allowing the vapor to cool to form an aerosol; and, c) an element permitting the mammal to inhale the aerosol.
In another kit aspect of the present invention, a kit for delivering zaleplon, zolpidem or zopiclone through an inhalation route to a mammal is provided which comprises: a) a composition comprising at least 5 percent by weight of zaleplon, zolpidem or zopiclone; and, b) a device that forms a zaleplon, zolpidem or zopiclone aerosol from the composition, for inhalation by the mammal. Preferably, the composition comprises at least 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent, 95 percent, 97 percent, 99 percent, 99.5 percent, 99.9 percent or 99.97 percent by weight of zaleplon, zolpidem or zopiclone.
Typically, the device contained in the kit comprises: a) an element for heating the zaleplon, zolpidem or zopiclone composition to form a vapor; b) an element allowing the vapor to cool to form an aerosol; and, c) an element permitting the mammal to inhale the aerosol.
BRIEF DESCRIPTION OF THE FIGURE
FIG. 1 shows a cross-sectional view of a device used to deliver sedative-hypnotic aerosols to a mammal through an inhalation route.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
“Aerodynamic diameter” of a given particle refers to the diameter of a spherical droplet with a density of 1 g/mL (the density of water) that has the same settling velocity as the given particle.
“Aerosol” refers to a suspension of solid or liquid particles in a gas.
“Aerosol drug mass density” refers to the mass of sedative-hypnotic per unit volume of aerosol.
“Aerosol mass density” refers to the mass of particulate matter per unit volume of aerosol.
“Aerosol particle density” refers to the number of particles per unit volume of aerosol.
“Amorphous particle” refers to a particle that does not contain more than 50 percent by weight of a crystalline form. Preferably, the particle does not contain more than 25 percent by weight of a crystalline form. More preferably, the particle does not contain more than 10 percent by weight of a crystalline form.
“Condensation aerosol” refers to an aerosol formed by vaporization of a substance followed by condensation of the substance into an aerosol.
“Inhalable aerosol drug mass density” refers to the aerosol drug mass density produced by an inhalation device and delivered into a typical patient tidal volume.
“Inhalable aerosol mass density” refers to the aerosol mass density produced by an inhalation device and delivered into a typical patient tidal volume.
“Inhalable aerosol particle density” refers to the aerosol particle density of particles of size between 100 nm and 5 microns produced by an inhalation device and delivered into a typical patient tidal volume.
“Mass median aerodynamic diameter” or “MMAD” of an aerosol refers to the aerodynamic diameter for which half the particulate mass of the aerosol is contributed by particles with an aerodynamic diameter larger than the MMAD and half by particles with an aerodynamic diameter smaller than the MMAD.
“Rate of aerosol formation” refers to the mass of aerosolized particulate matter produced by an inhalation device per unit time.
“Rate of inhalable aerosol particle formation” refers to the number of particles of size between 100 nm and 5 microns produced by an inhalation device per unit time.
“Rate of drug aerosol formation” refers to the mass of aerosolized sedative-hypnotic produced by an inhalation device per unit time.
“Settling velocity” refers to the terminal velocity of an aerosol particle undergoing gravitational settling in air.
“Sedative-hypnotic degradation product” refers to a compound resulting from a chemical modification of a sedative-hypnotic. The modification, for example, can be the result of a thermally or photochemically induced reaction. Such reactions include, without limitation, oxidation and hydrolysis.
“Typical patient tidal volume” refers to 1 L for an adult patient and 15 mL/kg for a pediatric patient.
“Vapor” refers to a gas, and “vapor phase” refers to a gas phase. The term “thermal vapor” refers to a vapor phase, aerosol, or mixture of aerosol-vapor phases, formed preferably by heating.
“Zaleplon” refers to N-[3-(3-cyanopyrazolo[1,5-a]pyrimidin-7-yl)phenyl]-N-ethylacetamide, which is a free base.
“Zaleplon” degradation product refers to a compound resulting from a chemical modification of zaleplon. The modification, for example, can be the result of a thermally or photochemically induced reaction. Such reactions include, without limitation, oxidation and hydrolysis. An example of a degradation products is C 13 H 9 N 5 (de-ethylation and de-amidation to provide unsubstituted aniline moiety).
“Zolpidem” refers to N,N,6-trimethyl-2-p-tolyl-imidazo[1,2-a]pyridine-3-acetamide, which is a free base.
“Zolpidem” degradation product refers to a compound resulting from a chemical modification of zolpidem. The modification, for example, can be the result of a thermally or photochemically induced reaction. Such reactions include, without limitation, oxidation and hydrolysis. An example of a degradation product is C 16 H 14 N 2 O (amide removal).
“Zopiclone” refers to 4-methyl-1-piperazinecarboxylic acid 6-[5-chloro-2-pyridinyl]-6,7-dihydro-7-oxo-5H-pyrrolo[3,4-b]pyrazin-5-yl ester
“Zolpiclone” degradation product refers to a compound resulting from a chemical modification of zopiclone. The modification, for example, can be the result of a thermally or photochemically induced reaction. Such reactions include, without limitation, oxidation and hydrolysis. Examples of degradation products include 2-amino-5-chloropyridine and 1-methyl piperazine.
Formation of Sedative-Hypnotic Containing Aerosols
Any suitable method is used to form the aerosols of the present invention. A preferred method, however, involves heating a composition comprising a sedative-hypnotic to form a vapor, followed by cooling of the vapor such that it condenses to provide a sedative-hypnotic comprising aerosol (condensation aerosol). The composition is heated in one of four forms: as pure active compound (i.e., pure zaleplon, zolpidem or zopiclone); as a mixture of active compound and a pharmaceutically acceptable excipient; as a salt form of the pure active compound; and, as a mixture of active compound salt form and a pharmaceutically acceptable excipient.
Salt forms of sedative-hypnotics (e.g., zaleplon, zolpidem or zopiclone) are either commercially available or are obtained from the corresponding free base using well known methods in the art. A variety of pharmaceutically acceptable salts are suitable for aerosolization. Such salts include, without limitation, the following: hydrochloric acid, hydrobromic acid, acetic acid, maleic acid, formic acid, and fumaric acid salts.
Pharmaceutically acceptable excipients may be volatile or nonvolatile. Volatile excipients, when heated, are concurrently volatilized, aerosolized and inhaled with the sedative-hypnotic. Classes of such excipients are known in the art and include, without limitation, gaseous, supercritical fluid, liquid and solid solvents. The following is a list of exemplary carriers within the classes: water; terpenes, such as menthol; alcohols, such as ethanol, propylene glycol, glycerol and other similar alcohols; dimethylformamide; dimethylacetamide; wax; supercritical carbon dioxide; dry ice; and mixtures thereof.
Solid supports on which the composition is heated are of a variety of shapes. Examples of such shapes include, without limitation, cylinders of less than 1.0 mm in diameter, boxes of less than 1.0 mm thickness and virtually any shape permeated by small (e.g., less than 1.0 mm-sized) pores. Preferably, solid supports provide a large surface to volume ratio (e.g., greater than 100 per meter) and a large surface to mass ratio (e.g., greater than 1 cm 2 per gram).
A solid support of one shape can also be transformed into another shape with different properties. For example, a flat sheet of 0.25 mm thickness has a surface to volume ratio of approximately 8,000 per meter. Rolling the sheet into a hollow cylinder of 1 cm diameter produces a support that retains the high surface to mass ratio of the original sheet but has a lower surface to volume ratio (about 400 per meter).
A number of different materials are used to construct the solid supports. Classes of such materials include, without limitation, metals, inorganic materials, carbonaceous materials and polymers. The following are examples of the material classes: aluminum, silver, gold, stainless steel, copper and tungsten; silica, glass, silicon and alumina; graphite, porous carbons, carbon yarns and carbon felts; polytetrafluoroethylene and polyethylene glycol. Combinations of materials and coated variants of materials are used as well.
Where aluminum is used as a solid support, aluminum foil is a suitable material. Examples of silica, alumina and silicon based materials include amphorous silica S-5631 (Sigma, St. Louis, Mo.), BCR171 (an alumina of defined surface area greater than 2 m 2 /g from Aldrich, St. Louis, Mo.) and a silicon wafer as used in the semiconductor industry. Carbon yarns and felts are available from American Kynol, Inc., New York, N.Y. Chromatography resins such as octadecycl silane chemically bonded to porous silica are exemplary coated variants of silica.
The heating of the sedative-hypnotic compositions is performed using any suitable method. Examples of methods by which heat can be generated include the following: passage of current through an electrical resistance element; absorption of electromagnetic radiation, such as microwave or laser light; and, exothermic chemical reactions, such as exothermic solvation, hydration of pyrophoric materials and oxidation of combustible materials.
Delivery of Sedative-Hypnotic Containing Aerosols
Sedative-hypnotic containing aerosols of the present invention are delivered to a mammal using an inhalation device. Where the aerosol is a condensation aerosol, the device has at least three elements: an element for heating a sedative-hypnotic containing composition to form a vapor; an element allowing the vapor to cool, thereby providing a condensation aerosol; and, an element permitting the mammal to inhale the aerosol. Various suitable heating methods are described above. The element that allows cooling is, in it simplest form, an inert passageway linking the heating means to the inhalation means. The element permitting inhalation is an aerosol exit portal that forms a connection between the cooling element and the mammal's respiratory system.
One device used to deliver the sedative-hypnotic containing aerosol is described in reference to FIG. 1 . Delivery device 100 has a proximal end 102 and a distal end 104 , a heating module 106 , a power source 108 , and a mouthpiece 110 . A sedative-hypnotic composition is deposited on a surface 112 of heating module 106 . Upon activation of a user activated switch 114 , power source 108 initiates heating of heating module 106 (e.g, through ignition of combustible fuel or passage of current through a resistive heating element). The sedative-hypnotic composition volatilizes due to the heating of heating module 106 and condenses to form a condensation aerosol prior to reaching the mouthpiece 110 at the proximal end of the device 102 . Air flow traveling from the device distal end 104 to the mouthpiece 110 carries the condensation aerosol to the mouthpiece 110 , where it is inhaled by the mammal.
Devices, if desired, contain a variety of components to facilitate the delivery of sedative-hypnotic containing aerosols. For instance, the device may include any component known in the art to control the timing of drug aerosolization relative to inhalation (e.g., breath-actuation), to provide feedback to patients on the rate and/or volume of inhalation, to prevent excessive use (i.e., “lock-out” feature), to prevent use by unauthorized individuals, and/or to record dosing histories.
Dosage of Sedative-Hypnotic Containing Aerosols
The dosage amount of sedative-hypnotics in aerosol form is generally no greater than twice the standard dose of the drug given orally. For instance, zaleplon, zolpidem and zopiclone are given orally at strengths of 5 mg or 10 mg for the treatment of insomnia. As aerosols, 0.5 mg to 40 mg of the compounds are generally provided per inspiration for the same indication. A typical dosage of a sedative-hypnotic aerosol is either administered as a single inhalation or as a series of inhalations taken within an hour or less (dosage equals sum of inhaled amounts). Where the drug is administered as a series of inhalations, a different amount may be delivered in each inhalation.
One can determine the appropriate dose of sedative-hypnotic containing aerosols to treat a particular condition using methods such as animal experiments and a dose-finding (Phase I/II) clinical trial. One animal experiment involves measuring plasma concentrations of drug in an animal after its exposure to the aerosol. Mammals such as dogs or primates are typically used in such studies, since their respiratory systems are similar to that of a human. Initial dose levels for testing in humans is generally less than or equal to the dose in the mammal model that resulted in plasma drug levels associated with a therapeutic effect in humans. Dose escalation in humans is then performed, until either an optimal therapeutic response is obtained or a dose-limiting toxicity is encountered.
Analysis of Sedative-Hypnotic Containing Aerosols
Purity of a sedative-hypnotic containing aerosol is determined using a number of methods, examples of which are described in Sekine et al., Journal of Forensic Science 32:1271-1280 (1987) and Martin et al., Journal of Analytic Toxicology 13:158-162 (1989). One method involves forming the aerosol in a device through which a gas flow (e.g., air flow) is maintained, generally at a rate between 0.4 and 60 L/min. The gas flow carries the aerosol into one or more traps. After isolation from the trap, the aerosol is subjected to an analytical technique, such as gas or liquid chromatography, that permits a determination of composition purity.
A variety of different traps are used for aerosol collection. The following list contains examples of such traps: filters; glass wool; impingers; solvent traps, such as dry ice-cooled ethanol, methanol, acetone and dichloromethane traps at various pH values; syringes that sample the aerosol; empty, low-pressure (e.g., vacuum) containers into which the aerosol is drawn; and, empty containers that fully surround and enclose the aerosol generating device. Where a solid such as glass wool is used, it is typically extracted with a solvent such as ethanol. The solvent extract is subjected to analysis rather than the solid (i.e., glass wool) itself. Where a syringe or container is used, the container is similarly extracted with a solvent.
The gas or liquid chromatograph discussed above contains a detection system (i.e., detector). Such detection systems are well known in the art and include, for example, flame ionization, photon absorption and mass spectrometry detectors. An advantage of a mass spectrometry detector is that it can be used to determine the structure of sedative-hypnotic degradation products.
Particle size distribution of a sedative-hypnotic containing aerosol is determined using any suitable method in the art (e.g., cascade impaction). An Andersen Eight Stage Non-viable Cascade Impactor (Andersen Instruments, Smyrna, Ga.) linked to a furnace tube by a mock throat (USP throat, Andersen Instruments, Smyrna, Ga.) is one system used for cascade impaction studies.
Inhalable aerosol mass density is determined, for example, by delivering a drug-containing aerosol into a confined chamber via an inhalation device and measuring the mass collected in the chamber. Typically, the aerosol is drawn into the chamber by having a pressure gradient between the device and the chamber, wherein the chamber is at lower pressure than the device. The volume of the chamber should approximate the tidal volume of an inhaling patient.
Inhalable aerosol drug mass density is determined, for example, by delivering a drug-containing aerosol into a confined chamber via an inhalation device and measuring the amount of active drug compound collected in the chamber. Typically, the aerosol is drawn into the chamber by having a pressure gradient between the device and the chamber, wherein the chamber is at lower pressure than the device. The volume of the chamber should approximate the tidal volume of an inhaling patient. The amount of active drug compound collected in the chamber is determined by extracting the chamber, conducting chromatographic analysis of the extract and comparing the results of the chromatographic analysis to those of a standard containing known amounts of drug.
Inhalable aerosol particle density is determined, for example by delivering aerosol phase drug into a confined chamber via an inhalation device and measuring the number of particles of given size collected in the chamber. The number of particles of a given size may be directly measured based on the light-scattering properties of the particles. Alternatively, the number of particles of a given size is determined by measuring the mass of particles within the given size range and calculating the number of particles based on the mass as follows: Total number of particles=Sum (from size range 1 to size range N) of number of particles in each size range. Number of particles in a given size range=Mass in the size range/Mass of a typical particle in the size range. Mass of a typical particle in a given size range=π*D 3 *φ/6, where D is a typical particle diameter in the size range (generally, the mean boundary MMADs defining the size range) in microns, φ is the particle density (in g/mL) and mass is given in units of picograms (g −12 ).
Rate of inhalable aerosol particle formation is determined, for example, by delivering aerosol phase drug into a confined chamber via an inhalation device. The delivery is for a set period of time (e.g., 3 s), and the number of particles of a given size collected in the chamber is determined as outlined above. The rate of particle formation is equal to the number of 100 nm to 5 micron particles collected divided by the duration of the collection time.
Rate of aerosol formation is determined, for example, by delivering aerosol phase drug into a confined chamber via an inhalation device. The delivery is for a set period of time (e.g., 3 s), and the mass of particulate matter collected is determined by weighing the confined chamber before and after the delivery of the particulate matter. The rate of aerosol formation is equal to the increase in mass in the chamber divided by the duration of the collection time. Alternatively, where a change in mass of the delivery device or component thereof can only occur through release of the aerosol phase particulate matter, the mass of particulate matter may be equated with the mass lost from the device or component during the delivery of the aerosol. In this case, the rate of aerosol formation is equal to the decrease in mass of the device or component during the delivery event divided by the duration of the delivery event.
Rate of drug aerosol formation is determined, for example, by delivering a sedative-hypnotic containing aerosol into a confined chamber via an inhalation device over a set period of time (e.g., 3 s). Where the aerosol is pure sedative-hypnotic, the amount of drug collected in the chamber is measured as described above. The rate of drug aerosol formation is equal to the amount of sedative-hypnotic collected in the chamber divided by the duration of the collection time. Where the sedative-hypnotic containing aerosol comprises a pharmaceutically acceptable excipient, multiplying the rate of aerosol formation by the percentage of sedative-hypnotic in the aerosol provides the rate of drug aerosol formation.
Utility of Sedative-Hypnotic Containing Aerosols
The sedative-hypnotic containing aerosols of the present invention are typically used for the treatment of insomnia. Other uses for the aerosols include, without limitation, the following: an anticonvulsant; an anxiolytic; and, a myorelaxant.
The following examples are meant to illustrate, rather than limit, the present invention.
Zolpidem and zopiclone are commercially available from Sigma. Zaleplon is available in capsule form (SONATA®) and can be isolated using standard methods in the art.
EXAMPLE 1
Volatilization of Zaleplon
A solution of 5.5 mg zaleplon in approximately 120 μL dichloromethane was coated on a 3 cm×8 cm piece of aluminum foil. The dichloromethane was allowed to evaporate. The coated foil was wrapped around a 300 watt halogen tube (Feit Electric Company, Pico Rivera, Calif.), which was inserted into a glass tube sealed at one end with a rubber stopper. Running 60 V of alternating current (driven by line power controlled by a variac) through the bulb for 7 s afforded zaleplon thermal vapor (including zaleplon aerosol), which collected on the glass tube walls. Reverse-phase HPLC analysis with detection by absorption of 225 nm light showed the collected material to be greater than 99% pure zaleplon.
EXAMPLE 2
Volatilization of Zolpidem
A solution of 5.3 mg zolpidem in approximately 120 μL dichloromethane was coated on a 3 cm×8 cm piece of aluminum foil. The dichloromethane was allowed to evaporate. The coated foil was wrapped around a 300 watt halogen tube (Feit Electric Company, Pico Rivera, Calif.), which was inserted into a glass tube sealed at one end with a rubber stopper. Running 60 V of alternating current (driven by line power controlled by a variac) through the bulb for 6 s afforded zolpidem thermal vapor (including zolpidem aerosol), which collected on the glass tube walls. Reverse-phase HPLC analysis with detection by absorption of 225 nm light showed the collected material to be greater than 99% pure zolpidem.
EXAMPLE 3
Volatilization of Zopiclone
A solution of 3.5 mg zopiclone in approximately 120 μL dichloromethane was coated on a 3 cm×8 cm piece of aluminum foil. The dichloromethane was allowed to evaporate. The coated foil was wrapped around a 300 watt halogen tube (Feit Electric Company, Pico Rivera, Calif.), which was inserted into a glass tube sealed at one end with a rubber stopper. Running 60 V of alternating current (driven by line power controlled by a variac) through the bulb for 6 s afforded zopiclone thermal vapor (including zopiclone aerosol), which collected on the glass tube walls. Reverse-phase HPLC analysis with detection by absorption of 225 nm light showed the collected material to be greater than 99% pure zopiclone.
EXAMPLE 4
Particle Size, Particle Density, and Rate of Inhalable Particle Formation of Zolpidem Aerosol
A solution of 10.7 mg zolpidem in 100 μL dichloromethane was spread out in a thin layer on the central portion of a 3.5 cm×7 cm sheet of aluminum foil. The dichloromethane was allowed to evaporate. The aluminum foil was wrapped around a 300 watt halogen tube, which was inserted into a T-shaped glass tube. Both of the openings of the tube were sealed with parafilm, which was punctured with fifteen needles for air flow. The third opening was connected to a 1 liter, 3-neck glass flask. The glass flask was further connected to a large piston capable of drawing 1.1 liters of air through the flask. Alternating current was run through the halogen bulb by application of 90 V using a variac connected to 110 V line power. Within 1 s, an aerosol appeared and was drawn into the 1 L flask by use of the piston, with collection of the aerosol terminated after 6 s. The aerosol was analyzed by connecting the 1 L flask to an eight-stage Andersen non-viable cascade impactor. Results are shown in table 1. MMAD of the collected aerosol was 2.9 microns with a geometric standard deviation of 2.1. Also shown in table 1 is the number of particles collected on the various stages of the cascade impactor, given by the mass collected on the stage divided by the mass of a typical particle trapped on that stage. The mass of a single particle of diameter D is given by the volume of the particle, πD 3 /6, multiplied by the density of the drug (taken to be 1 g/cm 3 ). The inhalable aerosol particle density is the sum of the numbers of particles collected on impactor stages 3 to 8 divided by the collection volume of 1 L, giving an inhalable aerosol particle density of 3.9×10 6 particles/mL. The rate of inhalable aerosol particle formation is the sum of the numbers of particles collected on impactor stages 3 through 8 divided by the formation time of 6 s, giving a rate of inhalable aerosol particle formation of 6.4×10 8 particles/second.
TABLE 1
Determination of the characteristics of a zolpidem condensation
aerosol by cascade impaction using an Andersen 8-stage non-viable
cascade impactor run at 1 cubic foot per minute air flow.
Mass
Particle size
Average particle
collected
Number of
Stage
range (microns)
size (microns)
(mg)
particles
0
9.0-10.0
9.5
0.1
2.2 × 10 5
1
5.8-9.0
7.4
0.3
1.4 × 10 6
2
4.7-5.8
5.25
0.4
5.3 × 10 6
3
3.3-4.7
4.0
0.9
2.7 × 10 7
4
2.1-3.3
2.7
1.1
1.1 × 10 8
5
1.1-2.1
1.6
0.8
3.7 × 10 8
6
0.7-1.1
0.9
0.4
1.1 × 10 9
7
0.4-0.7
0.55
0.2
2.3 × 10 9
8
0-0.4
0.2
0.0
0
EXAMPLE 5
Drug Mass Density and Rate of Drug Aerosol Formation of Zolpidem Aerosol
A solution of 8.3 mg zolpidem in 100 μL dichloromethane was spread out in a thin layer on the central portion of a 3.5 cm×7 cm sheet of aluminum foil. The dichloromethane was allowed to evaporate. The aluminum foil was wrapped around a 300 watt halogen tube, which was inserted into a T-shaped glass tube. Both of the openings of the tube were sealed with parafilm, which was punctured with fifteen needles for air flow. The third opening was connected to a 1 liter, 3-neck glass flask. The glass flask was further connected to a large piston capable of drawing 1.1 liters of air through the flask. Alternating current was run through the halogen bulb by application of 90 V using a variac connected to 110 V line power. Within seconds, an aerosol appeared and was drawn into the 1 L flask by use of the piston, with formation of the aerosol terminated after 6 s. The aerosol was allowed to sediment onto the walls of the 1 L flask for approximately 30 minutes. The flask was then extracted with acetonitrile and the extract analyzed by HPLC with detection by light absorption at 225 nm. Comparison with standards containing known amounts of zolpidem revealed that 3.7 mg of >97% pure zolpidem had been collected in the flask, resulting in an aerosol drug mass density of 3.7 mg/L. The aluminum foil upon which the zolpidem had previously been coated was weighed following the experiment. Of the 8.3 mg originally coated on the aluminum, 7.4 mg of the material was found to have aerosolized in the 6 s time period, implying a rate of drug aerosol formation of 1.2 mg/s. | The present invention relates to the delivery of sedative-hypnotics through an inhalation route. Specifically, it relates to aerosols containing sedative-hypnotics that are used in inhalation therapy. In a method aspect of the present invention, a sedative-hypnotic drug is administered to a patient through an inhalation route. The method comprises: a) heating a thin layer of a sedative-hypnotic, on a solid support, to form a vapor; and, b) passing air through the heated vapor to produce aerosol particles having less than 5% sedative-hypnotic drug degradation products. In a kit aspect of the present invention, a kit for delivering a sedative-hypnotic through an inhalation route is provided which comprises: a) a thin layer of a sedative-hypnotic drug and b) a device for dispensing said thin layer a sedative-hypnotic drug as a condensation aerosol. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to image signal processing that enables a user to discriminate a desired object from an entire image captured with an electronic endoscope.
2. Description of the Related Art
An electronic endoscope, having an imaging device at the end of an insertion tube, is used for medical examinations, industrial examinations, and so on. Light is irradiated from the end of the insertion tube to illuminate an object for observation. An optical image formed by the reflected light is captured by the imaging device, and the captured image is displayed on a monitor.
A medical endoscope is used for identifying abnormal tissue or a lesion of internal organs. The appearance of abnormal tissue or a lesion is different from that of healthy tissue. Based on the user's observation, the abnormal tissue or lesion can be identified.
However, the outer appearance of a lesion that exists deep under the surface of an organ is not clearly defined from that of healthy tissue. Therefore, it is often difficult to distinguish such a lesion.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide an endoscope processor that carries out signal processing on the image signal generated by an electronic endoscope in order that a lesion is easily distinguishable from a displayed image which corresponds to the image signal.
According to the present invention, an endoscope processor comprising a signal receiver, an average calculator, a difference calculator, an emphasizer, synthesizer, and an output block is provided. The signal receiver receives an image signal. The image signal is generated based on an optical image captured at a light receiving surface on an imaging device. The image signal comprises a plurality of pixel signals. The pixel signals are generated by a plurality of pixels according to the amounts of received light. The plurality of the pixels are arranged on the light receiving surface on the imaging device. The average calculator calculates the signal average value. The signal average value is the average of the signal levels of the pixel signals that one frame of one field of the image signal comprises. The difference calculator calculates a signal difference value. The signal difference value is the difference between the signal level of the pixel signal for the each pixel and the signal level of the signal average value. The emphasizer calculates an emphasized value by multiplying the signal difference value by a predetermined gain. The synthesizer generates an emphasized image signal. In the emphasized image signal, the pixel signal for each pixel is replaced with the sum of the emphasized value for each pixel and the signal average value. The output block outputs the emphasized image signal.
Further, the average calculator calculates the signal average value using the pixel signals, which are filtered according to their signal level, by a higher or lower limit, or both.
Further, each of the pixels is covered with a first or second color filter. First and second pixels are covered with the first and second color filter, respectively. The first and second pixels generate first and second pixel signals, respectively. The average calculator calculates first and second signal average values. The first and second signal average values are the signal average values corresponding to the first and second pixel signals, respectively. The difference calculator calculates first and second signal difference values. The first and second signal values are the signal difference values corresponding to the first and second pixel signals, respectively. The emphasizer calculates first and second emphasized values. The first and second emphasized values are emphasized values corresponding to the first and second pixel signals, respectively. The synthesizer generates the emphasized image signal. In the emphasized image signal, the first and second pixel signals are replaced with the sum of the first and second emphasized values for each pixel and the first and second signal average values, respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of the present invention will be better understood from the following description, with reference to the accompanying drawings in which:
FIG. 1 is a block diagram showing the internal structure of an endoscope system having an endoscope processor as an embodiment of the present invention;
FIG. 2 is a block diagram showing the internal structure of the image signal processing block; and
FIG. 3 is a flowchart describing the emphasizing image process, as carried out by the image signal processing block.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is described below with reference to the embodiments shown in the drawings.
In FIG. 1 , an endoscope system 10 comprises an endoscope processor 20 , an electronic endoscope 40 , and a monitor 50 . The endoscope processor 20 is connected to the electronic endoscope 40 and the monitor 50 via connectors (not depicted).
The whole structure of the endoscope system 10 is briefly explained. A light source 21 for illuminating an object (not depicted) is housed in the endoscope processor 20 . The light emitted from the light source 21 is irradiated onto an object (not depicted) via a light guide 41 housed in the electronic endoscope 40 .
An imaging device 42 , such as a CCD image sensor, is mounted in the electronic endoscope 40 . The image of an object which is irradiated by the illumination light is captured by the imaging device 42 . Subsequently, an image signal corresponding to the image of the captured object is generated by the imaging device 42 . The image signal is sent to the endoscope processor 20 , where predetermined signal processing is carried out on the image signal. The image signal, having undergone the predetermined signal processing, is converted into a composite video signal and sent to the monitor 50 , where the resulting image is displayed.
Next, each component of the endoscope system 10 is explained in detail, as follows: A diaphragm 22 and a condenser lens 23 are mounted in the optical path from the light source 21 to the incident end 41 a of the light guide 41 . The light, which is composed almost entirely of parallel light beams emitted by the light source 21 , is made incident on, and condensed onto the incident end 41 a by the condenser lens 23 .
The intensity of the light, made incident on the incident end 41 a , is controlled by adjusting the diaphragm 22 . The diaphragm 22 is adjusted by a motor 25 . The movement of the motor 25 is controlled by the diaphragm circuit 24 . The diaphragm circuit 24 is connected to an image signal processing block 30 via a system controller 26 . The image signal processing block 30 detects the magnitude of light received in a captured image of an object based on the image signal generated by the imaging device 42 . The diaphragm circuit 24 calculates the necessary degree of adjustment for the motor 25 based on the magnitude of light received.
A power circuit 27 , which supplies power to the light source 21 , is electrically connected to the system controller 26 . A control signal for switching the light source 21 on and off is output from the system controller 26 to the power circuit 27 . Consequently, the lighting status (on and off) of the light source 21 is controlled by the system controller 26 .
Further, the system controller 26 outputs a driving signal necessary for driving the imaging device 42 , to an imaging device driving circuit 28 . The imaging device 42 , which is driven by the imaging device driving circuit 28 , generates an image signal corresponding to the captured image of an object.
Further, the system controller 26 controls the activity of the whole endoscope processor 20 . An image signal processing block 30 is also controlled by the system controller 26 , as described later.
The light made incident on the incident end 41 a is transmitted to the exit end 41 b via the light guide 41 . The transmitted light illuminates a peripheral area around the head end of the insertion tube of the electronic endoscope 40 after passing through a diffuser lens 43 . An optical image of the illuminated object is focused onto the light receiving surface of the imaging device 42 by an object lens 44 .
A plurality of pixels (not depicted) is arranged in two dimensions on the light receiving surface of the imaging device 42 . Each pixel is covered with red, green, or blue color filter. Only red, green, or blue light components are able to pass through the red, green, and blue color filters, respectively. A light component produced by one of the color filters is made incident on the pixel that is covered by that color filter. Each pixel generates a pixel signal in accordance with the magnitude of the detected light component.
The image signal of one frame or one field captured by the imaging device 42 comprises a plurality of pixel signals generated by the plurality of the pixels on the light receiving surface.
The image signal generated by the imaging device 42 is sent to the image signal processing block 30 housed in the endoscope processor 20 . The image signal processing block 30 carries out normal image processing or emphasizing image processing on the image signal so that a normal image or an emphasized image is displayed on the monitor 50 , respectively. The normal image is the same as that of the captured image. The emphasized image is a partially-emphasized image of the normal image.
As shown in FIG. 2 , the image signal processing block 30 comprises a first signal processing block 31 , an extraction block 32 , an average calculation block 33 , a difference calculation block 34 , an emphasizing block 35 , a synthesizing block 36 , and a second signal processing block 37 .
When the emphasizing image processing is carried out, the first signal processing block 31 , the extraction block 32 , the average calculation block 33 , the difference calculation block 34 , the emphasizing block 35 , the synthesizing block 36 , and the second signal processing block 37 function, as described later. On the other hand, when the normal image processing is carried out, only the first and second signal processing blocks 31 , 37 function.
The image signal generated by the imaging device 42 is sent to the first signal processing block 31 . The first signal processing block 31 carries out predetermined signal processing, which includes color separation processing and color interpolation processing.
In the color separation processing, the image signal is separated into red, green, and blue signal components, which are pixel signals categorized in accordance with their specific magnitude of red, green, and blue light components, respectively. At this point, each pixel signal consists of only one of red, green, or blue color signal component because each pixel can directly generate only one color signal component corresponding to its covering color filter.
During the color interpolation processing, in addition to the generated color signal component, two additional color signal components inherent within each pixel signal prior to the color interpolation processing, are synthesized. For example, in a pixel signal generated by a pixel covered with a green color filter and consisting of a green color signal component, the red and blue color signal components corresponding to the pixel are synthesized. Each pixel signal then consists of all three color signal components.
Further, the image signal, which is an analog signal, is converted to image data, which is digital data.
When normal image processing is carried out, the image data is sent from the first signal processing block 31 to the second signal processing block 37 . When emphasizing image processing is carried out, the image data is sent from the first signal processing block 31 to the extraction block 32 and the difference calculation block 34 .
The extraction block 32 determines whether the data levels of red, green, and blue data components for each pixel for an entire image are within the predetermined range or not. The red, green, and blue data components are digital data converted from the red, green, and blue signal components, respectively. The data level of each color data component corresponds to the signal level of each color signal component.
Higher and lower limits of a predetermined range for the red data component, hereinafter referred to as HLr and LLr, respectively, are predetermined and memorized in a ROM (not depicted). Similarly, higher and lower limits of a predetermined range for the green data component, hereinafter referred to as HLg and LLg, respectively, are predetermined and memorized in the ROM. Similarly, higher and lower limits of a predetermined range for the blue data component, hereinafter referred to as HLb and LLb, respectively, are predetermined and memorized in the ROM. The extraction block 32 reads the HLr, LLr, HLg, LLg, HLb, and LLb from the ROM.
The extraction block 32 extracts a red data component whose data level is in the range between HLr and LLr. The extracted red data component is sent to the average calculation block 33 . Similarly, the extraction block 32 extracts a green data component whose data level is in the range between HLg and LLg. The extracted green data component is sent to the average calculation block 33 . Similarly, the extraction block 32 extracts a blue data component whose data level is in the range between HLb and LLb. The extracted blue data component is sent to the average calculation block 33 .
The average calculation block 33 calculates the average value of a plurality of the received red data components within one field or frame of image data, hereinafter referred to as the red average value. Similarly, the average calculation block 33 calculates the average value of a plurality of the received green data components within one field or frame of image data, hereinafter referred to as the green average value. Similarly, the average calculation block 33 calculates the average value of a plurality of the received blue data components within one field or frame of image data, hereinafter referred to as the blue average value. The data of red, green, and blue average value is sent to the difference calculation block 34 and the synthesizing block 36 .
The difference calculation block 34 also receives the image data, as described above. The difference calculation block 34 calculates a red difference value for each pixel by subtracting the received red average value from each of all the data level of the red data components included in one frame or one field of the image data corresponding to that red average value. Similarly, the difference calculation block 34 calculates a green difference value for each pixel by subtracting the received green average value from each of all the data level of the green data components included in one frame or one field of the image data corresponding to that green average value. Similarly, the difference calculation block 34 calculates a blue difference value for each pixel by subtracting the received blue average value from each of all the data level of the blue data components included in one frame or one field of the image data corresponding to that blue average value.
The data of the red, green, and blue difference values is sent to the emphasizing block 35 . The emphasizing block 35 calculates red, green, and blue emphasized values for each pixel by multiplying the red, green, and blue difference values by a predetermined gain of more than one.
The data of the red, green, and blue emphasized value is sent to the synthesizing block 36 . In addition, the data of the red, green, and blue average values is also sent to the synthesizing block 36 , as described above.
The synthesizing block 36 generates emphasized image data that corresponds to the emphasized image. The emphasized image data is generated based on the red, green, and blue emphasized values and the red, green, and blue average values. How the synthesized image data is generated is explained in detail below.
The synthesizing block 36 calculates the sum of the red average value and the red emphasized value for each pixel. The sum of the red average value and the red emphasized value is designated as the magnitude of the red light component in the emphasized image for each pixel. Similarly, the synthesizing block 36 calculates the sum of the green average value and the green emphasized value for each pixel. The sum of the green average value and the green emphasized value is designated as the magnitude of the green light component in the emphasized image for each pixel. Similarly, the synthesizing block 36 calculates the sum of the blue average value and the blue emphasized value for each pixel. The sum of the blue average value and the blue emphasized value is designated as the magnitude of the blue light component in the emphasized image for each pixel.
The emphasized image data is then sent to the second signal processing block 37 . The second signal processing block 37 carries out predetermined signal processing, such as contrast adjustment processing and enhancement processing, on the emphasized image data. In addition, D/A conversion processing is carried out for the emphasized image data, which is subsequently converted to an analog signal. Further, a composite video signal, which includes the image signal and a synchronizing signal is generated.
Incidentally, when normal image processing is carried out, the image data is sent from the first signal processing block 31 directly to the second signal processing block 37 , which carries out predetermined data processing on the received image data and generates a composite video signal corresponding to the normal image.
The composite video signal is sent to the monitor 50 , where an image based on the composite video signal is displayed.
The emphasizing image processing is carried out by the image signal processing block 30 , as explained below in relation to the flowchart in FIG. 3 . The emphasizing image processing starts when a user inputs a command to start the emphasizing image processing.
At step S 100 , the first signal processing block 31 receives one frame or one field of an image signal from the imaging device 42 . At step S 101 , the first signal processing block 31 carries out predetermined signal processing, which includes color separation processing and color interpolation processing. At this point red, green, and blue data components for each pixel are generated. After finishing the predetermined signal processing, the process proceeds to step S 102 .
At step S 102 , the extraction block 32 determines whether or not the data levels of red, green, and blue data components, which one frame or one field of the image data includes, are within the predetermined range. The extraction block 32 extracts the red, green, and blue data components which are within the predetermined range. After the extraction, the process proceeds to step S 103 .
At step S 103 , the average calculation block 33 calculates the red, green, and blue average values based on a plurality of the extracted red, green, and blue data components, respectively. After calculation of the average values, the process proceeds to step S 104 .
At step S 104 , the difference calculation block 34 calculates the red, green, and blue difference values based on the average values calculated at step S 103 and the data level of red, green, and blue data components for each pixel. After calculation of the difference values, the process proceeds to step S 105 .
At step S 105 , the emphasizing block 35 calculates the red, green, and blue emphasized values for each pixel by multiplying the red, green, and blue difference values by the predetermined gain. After calculation of the emphasized values, the process proceeds to step S 106 .
At step S 106 , the synthesizing block 36 generates emphasized image data based on the red, green, and blue average values calculated at step S 103 and the red, green, and blue emphasized values calculated at step S 105 . For the emphasized image data, the sum of the red emphasized value for each pixel and the red average value is designated as the magnitude of the red light component for each pixel. Similarly, in the emphasized image data, the sum of the green emphasized value for each pixel and the green average value is designated as the magnitude of the green light component for each pixel. Similarly, in the emphasized image data, the sum of the blue emphasized value for each pixel and the blue average value is designated as the magnitude of the blue light component for each pixel. After generation of the emphasized image data, the process proceeds to step S 107 .
At step S 107 , the second signal processing block 37 carries out predetermined signal processing including contrast adjustment processing and enhancement processing, on the emphasized image data, and generates a composite video signal. The second signal processing block 37 then sends the composite video signal to the monitor 50 , where an image corresponding to the composite video signal is displayed.
At step S 108 , it is determined whether there is an input command to finish the emphasizing image processing present. If there is, the emphasizing image processing for the image signal finishes. If there is not, the process returns to step S 100 . The processes from step S 100 to step S 108 are repeated until there is an input command to finish the emphasizing image processing present.
In the above embodiment, an unclear image can be converted into a clear image. Accordingly, a lesion that is not distinguishable in a normal image can be displayed more clearly, as described below.
Consider an example where a mass of capillaries or an adenoma has formed under the surface of a lesion, such as a polyp. A doctor identifies such a lesion by observing the appearance of the mass of capillaries or adenoma. However, it is difficult to observe a mass of capillaries because both the surface of the internal organ and capillaries is reddish. In addition, it is difficult to identify a bulge, which is characteristic of an adenoma, because there is little change of color or brightness in the bulge.
However, the endoscope processor 20 generates an emphasized image, in which a small difference of brightness and color in the normal image is emphasized by magnifying the difference between the average values of the red, green, and blue signal components and the red, green, and blue signal components for each pixel. Accordingly, a doctor is easily able to identify a lesion such as a polyp without relying on skill.
In an image captured by an endoscope, the size of a lesion is generally much smaller than that of a normal organ, and the number of pixels corresponding to a lesion is much less than that of a normal organ. Consequently, in the above embodiment, the red, green, and blue average values are substantially equal to the average values of red, green, and blue data components of the pixels corresponding to a normal organ. Therefore, the average value can be regarded as a standard value of color data components corresponding to a normal organ. In the above embodiment, by generating the emphasized image data based on such average values, a lesion will be more distinguishable from a normal organ.
In addition, the color of the organ can be altered by adjusting the predetermined gains for multiplying the red, green, and blue difference values. In prior art, the pigment of a specified color, such as indigo, is used as a coloring in order to enhance the edges of an entire image. However, an image where an edge is enhanced by changing the level of a color in the image can be displayed without using a pigment.
In the above embodiment, the emphasized image data is generated by carrying out a calculation involving average values, difference values, and emphasized values for all of the red, green, and blue data components. However, even if the emphasized image data is generated by carrying out a calculation of their values for at least one color data component, an effect similar to the above embodiment can still be achieved.
In the above embodiment, each pixel of the imaging device 42 is covered with either a red, green, or blue color filter, and the emphasized image data is generated based on the red, green, and blue data components. However, each pixel of the imaging device 42 can also be covered with another color filter and the emphasized image data can be generated based on the color data components corresponding to the color filter covering the pixel.
In the above embodiment, the emphasized image data is generated based on red, green, and blue data components. However, the emphasized image data can also be generated based on other data components used to synthesize a color received at each pixel. For example, a luminance data component and a color difference data component for each pixel can be generated based on the red, green, and blue signal components for each pixel and the emphasized image data can be generated by carrying out the calculation of average values, difference values, and emphasized values on the luminance signal component and the color difference signal component.
In the above embodiment, the red average value is calculated using only red data components of which the data level is within the range between HLr and LLr, and the green average value is calculated using only green data components of which the data level is within the range between HLg and LLg, and the blue average value is calculated using only blue data components of which the data level is within the range between HLb and LLb. However, it is possible that the red, green, and blue average values could be calculated using red, green, and blue data components which have been filtered according to their signal level, using a higher limit, or a lower limit, or have not been filtered at all.
However, it is preferable to calculate the average value while excluding data components of which the data level is higher than an upper limit or lower than a lower limit. Generally speaking, if a pixel detects a component which is extremely dark or extremely bright, it does not corresponding to an object which needs to be observed. In addition, the average value may be too low or too high if there are many pixels which are extremely dark or extremely bright, respectively. Consequently, an emphasized image based on the average value of all the detected data components may be too dark or bright to correctly observe an object when compared to the emphasized image based on the average value of the data components within a predetermined range.
The above embodiment can be implemented by installing a computer program for emphasizing an image onto an all-purpose endoscope processor. The program for emphasizing an image comprises a controller code segment for receiving, an average calculation block code segment, a difference calculation code segment, an emphasizing block code segment, a synthesizing block code segment, and a driver code segment for the output.
In the above embodiment, the endoscope processor 20 carries out signal processing on the image signal generated by the electronic endoscope 40 , which comprises an insert tube to be inserted from outside. However, the endoscope processor can also carry out signal processing on an image signal generated by any other electronic endoscope, such as a capsule endoscope.
Furthermore, in the above embodiment, the endoscope processor 20 receives the image signal, and carries out the above signal processing on the received image signal in real time. However, an endoscope image playback apparatus, which receives an image signal stored in internal or external memory, then carries out the above signal processing, including the emphasizing image processing, on the stored image signal while playing back the stored images.
Although the embodiments of the present invention have been described herein with reference to the accompanying drawings, obviously many modifications and changes may be made by those skilled in this art without departing from the scope of the invention.
The present disclosure relates to subject matter contained in Japanese Patent Application No. 2006-136541 (filed on May 16, 2006), which is expressly incorporated herein, by reference, in its entirety. | An endoscope processor comprising a signal receiver, an average calculator, a difference calculator, an emphasizer, a synthesizer, and an output block is provided. The signal receiver receives an image signal generated by an imaging device. The image signal comprises a plurality of pixel signals. The average calculator calculates a signal average value. The difference calculator calculates a signal difference value. The emphasizer calculates an emphasized value by multiplying the signal difference value by a predetermined gain. The synthesizer generates an emphasized image signal, in which the pixel signal for each pixel is replaced with the sum of the emphasized value for each pixel and the signal average value. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image reading device that converts light passed through an original image into electrical signals using a photoelectric conversion element, such as a CCD (Charged Coupled Device) camera, and, more particularly, to such an image reading device capable of masking a specified range of the original image.
2. Description of the Related Art
In the aforementioned field, it is known to use devices such as shading sheets to block out unwanted portions of image light being projected from a translucent original, such as a negative or a transparency. Borders and excess image areas are typically blocked out in this manner. Conventionally, such as shown in FIG. 10, several shading sheets are cut so as to block out these unwanted areas when placed on and around the original. The user would then stack the shading sheets on the original before transmitting light therethrough.
Most image reading devices use an original cassette glass for holding the image. An original holding glass is typically placed over top of the original to secure it in place. Light is transmitted through the original and recorded as electrical signals by a photoelectric conversion element, such as a CCD output. Currently, equipment designed to digitize originals must rely on shading sheets to eliminate excess areas. The shading sheets are held between the cassette glass and the holding glass with the image. As the light cannot pass through the shielding, the camera only sees those regions of the image which the user wishes to be recorded.
Each image to be processed in the aforementioned manner requires a different set of shields to achieve the desired results. Even if only the clear borders of each image are masked, there is still a need for multiple shading sheets, one for each size of original to be processed. There is a practical limit to the different types of sheets that can be prepared, thus limiting the user to a defined number of formats and shading schemes. It is also difficult to maintain the full set of shielding sheets due to the inevitable damage and loss of such sheets. As such, there exists a need for an apparatus and a method for masking an area of an original without using light shielding sheets.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a light shielding device capable of shielding a variable area of an original image.
It is another object of the present invention to provide a light shielding device capable of shielding a portion of an original image based upon pre-defined values.
It is yet another object of the present invention to provide an image reading device having a light shading device capable of shielding areas of an original image based upon pre-defined values.
It is yet a further object of the invention to provide an image reading device capable of determining which areas of an image are to be shielded.
It is yet a further object of the invention to provide an image reading device capable of determining which areas of an original image are to be shielded and then causing those images to be so shielded during the actual scanning of the original image.
Additional objects and advantages of the invention will be set forth in part in the description that follows, and in part, will be obvious from the description, or may be learned by practice of the invention.
The foregoing objects of the present invention are achieved by providing an image reading device that includes a light modification unit that masks regions of an original image based upon values inputted before or during the actual scanning of the image. The above objects of the present invention may also be achieved with an image reading device that includes a light modification unit able to shield regions of an original image based upon values derived by the image reading device during a pre-scan sequence of the original image.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the invention will become apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is an isometric diagram of the light modification apparatus and image holding device for an image reading device according to a preferred embodiment of the invention.
FIG. 2 is a cross-sectional view of an image reading device in accordance with a preferred embodiment of the present invention.
FIG. 3 is a block diagram of the image reading device in accordance with the preferred embodiment of the present invention.
FIG. 4 is a flow chart showing an example of the operation of the image reading device according to the preferred embodiment of the present invention.
FIG. 5 is a flow chart showing an example of the pre-scan routine performed by the image reading device according to the preferred embodiment of the present invention.
FIG. 6A is a top view of the original image holding apparatus and light modification apparatus of the image reading device according to an embodiment of the present invention.
FIGS. 6B and 6C are graphs showing an example output of a CCD in accordance with an embodiment of the present invention.
FIG. 7A is a top view of the image holding apparatus and light modification apparatus of an image reading device in accordance with an embodiment of the present invention.
FIGS. 7B and 7C are graphs showing an example of the output of the CCD in accordance with an embodiment of the present invention.
FIG. 8 is a top view of the original image holding apparatus and light shielding apparatus of an image reading device according to another embodiment of the prese invention.
FIG. 9 is a block diagram of an image reading device in accordance with the alternative embodiment of the present invention, as shown in FIG. 9 .
FIG. 10 is an isometric view of a conventional original image holding device and light shielding sheets.
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, wherein like reference numerals refer to like elements throughout.
Referring now to FIGS. 1 and 2, wherein shown is a configuration of a first embodiment of an image reading device according to the present invention. As used herein, the term “original” shall refer to the translucent image carrier to be read. Referring to FIG. 2, an original cassette 13 , attached to the upper surface of main unit 11 , holds the original 12 . Original cassette 13 is connected to motor 35 which causes the cassette to move in the direction of the sub-scan indicated by the arrow A—A. The original 12 is held between an original cassette glass 14 and an original holding glass 15 . A light source 16 is secured to the main unit 11 above the path of the sub-scan. The light emitted by source 16 is transmitted through original 12 , reflected by three reflecting mirrors 17 , 18 , 19 , and travels through lens system 20 onto CCD 21 . CCD 21 receives the image and converts it into electrical signals.
Between light source 16 and cassette 13 , on the optical axis 22 uniting light source 16 and reflecting mirror 17 , a narrow transparent plate 23 is positioned which spans cassette 13 in a direction perpendicular to the direction of the sub-scan. The narrow transparent plate 23 has two glass plates holding light transmittance element 24 therebetween. Light transmittance element 24 comprises components, such as LCDs and/or electrochromatic elements, in a linear matrix form. The light transmittance of specified portions of transmittance element 24 is controlled by applying a specified voltage to the LCDs or electrochromatic elements. Light is shaded if the transmittance of the elements approaches zero percent.
Referring now to FIG. 3, wherein shown is a block diagram of an image reading device according to the preferred embodiment of the present invention, as shown in FIGS. 1 and 2. A CPU 32 controls the various elements of the image reading device according to a program stored in ROM 33 . Control includes executing the image reading operation stored in ROM 33 . The data necessary for executing the various processing operations is stored, as necessary, in a RAM 34 . Input section 31 operates to receive specific commands.
An interface (I/F) 36 outputs signals corresponding to the operation of an input section 31 to CPU 32 through a bus. The data outputted by the CCD 21 is supplied to the CPU 32 through the bus. CPU 32 then typically supplies this data to RAM 34 where it is stored for future operations. In addition, CPU 32 controls the light source 16 through interface 36 , causing light to be emitted. Similarly, CPU 32 controls light transmittance element 24 and sets specific elements therein to the desired light transmittance levels. Moreover, CPU 32 drives motor 35 through interface 36 to transport original cassette 13 during the scanning operation.
Referring now to FIGS. 4 and 5, therein depicted are flow charts explaining the operation of the image reading device according to the preferred embodiment. First, in step 101 , original 12 is set at the desired position on original cassette 13 . Next, in step 102 , the preliminary scan (“pre-scan”) is performed to determine which areas of the image should be masked during the actual scan. The pre-scan is started when input section 31 is operated and a read-start command is given. The CPU 32 then activates light source 16 , causing original cassette 13 to be illuminated.
CPU 32 subsequently drives motor 35 to transfer the original cassette in the direction of the sub-scan, as shown by arrow A—A in FIG. 2 . Thus, the light emanating from the light source 16 illuminates the original cassette 13 , passing through the original 12 , and is reflected by reflecting mirrors 17 , 18 , 19 towards lens system 20 . Lens system 20 focuses the light and directs it to the CCD 21 for processing.
The details of pre-scan step 102 are shown in FIG. 5 . For exemplary purposes, the pre-scan process described below is for the purpose of masking the border of an original. It can be recognized by one skilled in the art that other areas can be selected and masked by changing the selection criteria. First, in step 301 , the original cassette is transported such that the first pixel line of the cassette is placed into the read position, i.e., in optical path 22 . Next, the variable n, used to indicate the read position, is set to 1. Thereafter, in step 302 , the first pixel line is read by CCD 21 . The pixel line is read perpendicular to the direction of the sub-scan, in the direction of the main scan. Once the pixel line has been read, the mask range of that line is determined in step 303 .
To determine the mask range of the pixel line, the CPU 32 stores the data gathered by the CCD 21 into RAM 34 . This stored data is compared with a reference value, set in advance, to obtain the position of the edge of the main scan of original 12 . Typically the light that passes through original cassette 13 outside the region occupied by the original 12 is greater in quantity than the light which must also pass through the original 12 . Thus, when the reference value is set to a light quantity value between these two, the position of the edge of the original can be detected. The area to be masked can be determined from this edge position.
The position to be masked as determined in step 303 is placed into RAM 34 in step 304 .
In the subsequent step 305 , the current read line, as indicated by the variable n, is compared to a value m that indicates the last line of the original cassette 13 . If n is less than m, n is incremented and the cassette is transported to the next pixel line in step 306 . Thereafter, the process repeats from step 302 . The image reading device will continue to read subsequent pixel lines and to determine the masking range for each pixel line until the last line is reached, at which point the determination, in step 305 , will fail and the pre-scan will end. Through this process, the position of the edge of the original 12 on the original cassette 13 is attained for each pixel line and stored in RAM 34 .
After the pre-scan sequence has been completed, the actual scan is initiated in step 103 . In preparation for the actual scan, original cassette 13 is returned to the initial position. This time as the cassette is being driven during the actual scan, the light transmittance element 24 , attached to transparent plate 23 , is driven as a mask according to the data stored in RAM 34 . The areas that were determined in step 303 to be masked can be blocked by modifying the transmittance of the elements in light transmittance element 24 to zero percent (or some sufficiently small value). Conversely, those areas that do not need to be masked are controlled such that their light transmittance becomes 100 percent (or sufficiently large value). In this way, the light of the border of original 12 is, in effect, shaded.
Referring again to FIG. 1, along with transporting the original cassette in the direction indicated by arrow A, voltage is imparted to the elements of the light transmittance element 24 in the mask area determined in step 303 . By performing this light shielding for each pixel line lying on the direction of main-scan, along the sub-scan direction, according to the data stored in RAM 34 the specified area of the image of original 12 can be masked. Thus, only the specified area of the image is extracted by CCD 21 . FIGS. 6A-C and 7 A-C show conceptual examples of CCD's 21 output intensity in relationship to various positions of the original 12 upon the original cassette 13 . As shown in FIGS. 6A-C, when the two sides of the original 12 are at right angles to the direction of the sub-scan (see FIG. 6 A), the output of the CCD 21 varies during the pre-scan (FIG. 6 B). As can be seen, the outside areas of original cassette 13 that are not obstructed by the image of original 12 display a high transmittance of light. In contrast, those areas obscured by the image of original 12 display lesser transmittance values. Area 37 indicates the portion of the image of the original that is to be read by CCD 21 . FIG. 6C is representative of the desired output of CCD 21 during the actual scan while light transmittance element 24 is in use. Those areas determined to be outside the image are masked and thus display low transmittance.
Referring now to FIG. 7A, this figure portrays a situation where an original 12 is skewered on original cassette 13 . In this case, the output of the CCD during the pre-scan, FIG. 6B, and actual scan, FIG. 7C, are appropriately skewered to the right.
Where LCDs and other electrochromatic elements are used as the light transmittance element 24 , there are instances in which the light emanating from the light source 16 cannot be completely shaded, but if the light can be shaded to a certain extent, the dynamic range of CCD 21 can be concentrated in the read range of the original 12 .
Although the first embodiment of the present invention has been described with respect to specific components for the image reading device, it will be recognized that the first embodiment is not limited to those specific components. For example, although the first embodiment has been described with respect to a CCD, it will be recognized that other kinds of image reading devices can be employed. Further, it will be recognized that, while in the above embodiment the optical system (light source 16 , light transmittance element 24 , reflecting mirror 17 , 18 , 19 , lens system 20 and CCD 21 ) is stationary while the original cassette 13 is transported through optical axis 22 , the optical system could be transported instead of the original cassette. In fact, it is only necessary that the optical system and the original cassette move in relationship to one another.
It will also be recognized by one of ordinary skill in the art that the light transmittance element 24 need not be positioned between original cassette 13 and the light source 16 , but rather must only be on the optical path from light source 16 to the CCD 21 . It has been found that the position between original cassette 13 and light source 16 offers little deterioration in image quality, but requires that the length of transmittance element 24 be as wide as original cassette 13 . On the other hand, if light transmittance element 24 is positioned between the original cassette 13 and the lens system 20 , it must only be a length that corresponds to the aperture of lens system 20 . While this enables cost reductions, the light from original 12 is typically dampened by the glass plate that forms transparent plate 23 , thus deteriorating the quality of the image of original 12 .
Referring now to FIG. 8, this figure shows a top view of an image reading device according to a second embodiment of the present invention, wherein the light transmittance is controlled by a mechanically operated light shielding plate. Like elements in the figures of the first and second embodiments are referred to by like reference numerals, and a description of the like elements will not be repeated in detail here.
According to the second embodiment of the present invention, the image reading device has light shielding plates 42 L and 42 R which are positioned to one side of original cassette 13 . Nuts 43 R and 43 L are attached to light shielding plates 42 R and 42 L, respectively. Nuts 43 R and 43 L are threaded onto screws 44 R and 44 L, respectively. The position of light shielding plates 42 R and 42 L, with respect to original cassette 13 and the pixel line to be scanned, shown by line 22 , is controlled respectively by motors 41 R and 41 L, which rotate corresponding screws 44 R and 44 L.
FIG. 9 is a block diagram of the electrical configuration for the image reading device according to the second embodiment of the present invention. As can be seen, motors 41 L and 41 R are connected to interface 36 for control by CPU 32 . The rest of the electrical configuration is similar to that of the first embodiment.
When motors 41 L and 41 R are driven by CPU 32 , the screws 44 L and 44 R are rotated. This rotation acts to lever nuts 43 L and 43 R in the direction of the sub-scan. Light shielding plates 42 L and 42 R are formed such that their inner sides 42 La and 42 Ra are angled with respect to the sub-scan direction. Therefore, the position at which the light from light source 16 is shaded changes as the plates are moved in relationship to pixel scanning line 22 . As will be readily apparent, the specified areas of the image of original 12 can be masked in the same way as the case in which light transmittance element 24 was used.
In operation, the main difference between the first embodiment and the second embodiment is that, in the first embodiment, multiple originals can be placed across scan line 22 and still be correctly masked. Due to the mechanical limitations of the second embodiment, only one original can be placed across scan line 22 .
Although the second embodiment of the present invention has been described with respect to specific components for the image reading device, it will be recognized that the second embodiment is not limited to those specific components. For example, although the second embodiment has been described with respect to triangular shielding plates, it will be recognized that other shapes may be used. Further, it will be recognized that other mechanisms for driving the shields can be employed.
Although a few preferred embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalence. | An image reading device that detects the edge of the image to be read and masks the areas outside the edge during the read. The image reading device includes a light transmittance modification device in the optical path between the image illumination source and the photoelectric conversion device. During a pre-scan of the image, the position of the edge of the image is stored in a memory unit. During the actual scan of the image to be read, the edge data is fed to the modification device for each position of the scanner. The modification device blocks out those portions of the area being scanned that are outside the image. In this manner, the image is read while the border area is masked. | 7 |
This application is a division of Ser. No. 08/661,819 filed Jun. 11, 1996, now U.S. Pat. No. 5,716,092.
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle visor and particularly to the visor body and mounting construction and its manufacturing method.
Visor bodies have been made utilizing a variety of materials including butterfly-shaped polypropylene cores which are upholstered and folded to complete a visor body, fiberboard cores of similar butterfly shape and foam core construction covered by upholstery. The solid foam core construction is difficult to upholster to obtain a visor configuration with an upholstered appearance that is sufficiently attractive to provide a commercial product. This results since, with a foam core, there are, unlike the butterfly core construction, no edges around which to tuck the upholstery fabric to provide a trim appearance. Further, the dated utilization of an upholstery bead and stitching is both excessively expensive and unattractive in today's modern vehicle interior designs.
In addition, visor cores made of a foam material are difficult to mount to a vehicle inasmuch as the foam material itself is not sufficiently structurally rigid to receive conventional pivot rod torque control and mounting structures. Typically, internal reinforcing members are required for foam core visors. Thus, although foam cores provide a relatively inexpensive and lightweight visor body, there is difficulty both in upholstering the visor in an attractive manner and in mounting such a visor core to the vehicle.
It is also desirable to manufacture visor cores of a recyclable material which is relatively inexpensive and is environmentally friendly. To this end, the present invention contemplates a visor construction which improves upon conventional foam core constructions and in some embodiments utilizes core material other than a polymeric foam.
SUMMARY OF THE PRESENT INVENTION
Visors embodying the present invention, according to one embodiment, comprise a closed-cell, semi-rigid urethane foam material thermoformed from sheets into a visor core construction with a reinforced backbone mounted along an edge thereof for mounting the visor so formed to a vehicle. The visor is upholstered utilizing a laminate of adhesive and upholstery material to assure the outer upholstery material adheres smoothly to the visor core and provides a tear-seal edge which is trim in appearance.
According to one embodiment of the invention, a blend of kenaf and polymeric fibers are employed as the core material, which is laminated with upholstery material to complete the visor construction as in the first embodiment. In yet another embodiment of the invention, a butterfly-type core construction is made of a high density kenaf and polymeric fiber blend and upholstered in a manner employed with other butterfly visor core constructions.
With the visor of the present invention, therefore, a sleek, lightweight visor construction is achieved using either a urethane foam core or recycled material employed in the construction of the visor core to both reduce the visor cost and provide a lightweight attractive visor suitable for today's modern vehicle interior design.
These an other features, objects and advantages of the present invention will become apparent upon reading the following description thereof together with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of the interior of a vehicle including visors of the present invention;
FIG. 2 is an enlarged exploded perspective view of one of the visors shown in FIG. 1;
FIG. 3 is a vertical cross-sectional view of one of the visors shown in FIG. 1 taken along section lines III--III of FIG. 1;
FIG. 4 is an enlarged view of the encircled area IV in FIG. 3;
FIG. 5 is an enlarged fragmentary partly broken-away view of the laminated structure of the visor shown in FIGS. 1-4;
FIG. 6 is a block diagram of the steps of the method of manufacturing the visor shown in FIGS. 1-5;
FIG. 7 is a fragmentary vertical cross-sectional view of another embodiment of the present invention utilizing an alternate core material;
FIG. 8 is a block diagram of the steps of the method of manufacturing the visor shown in FIG. 7;
FIG. 9 is a perspective view of an alternative embodiment of a visor core manufactured according to an alternative process;
FIG. 10 is an enlarged fragmentary cross-sectional view of a visor employing a core as shown in FIG. 9; and
FIG. 11 is a block diagram of the steps of the method of manufacturing the visor shown in FIGS. 9 and 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIG. 1, there is shown a vehicle 10, such as an automobile, having a pair of visor assemblies 20 and 30 mounted on the driver and passenger sides, respectively. The visors are mounted above the windshield 12 on opposite sides of the rearview mirror assembly 14 and are mounted to the roof structure 16 covered by an integrally molded headliner 18 having a surface fabric or upholstery which the visors are upholstered to match. The visors are conventionally mounted to the roof 16 of the vehicle utilizing pivot rod assemblies 22 and 32, respectively, which secures one end of each of the visors to the vehicle roof 16. Clips 24 and 34, respectively, mounted above the windshield to the vehicle roof releasably engage visor pins 48 to allow the visors to swing from the front windshield position shown to either the driver side window 11 or the passenger side window 13.
Visors 20 and 30 are substantially identical in construction, although the mounting arrangement is reversed for the driver and passenger sides. Visor 20 is shown in a lowered sun-blocking position for use also of a vanity mirror 26 mounted therein, as described in greater detail below in connection with FIGS. 2-5. Visor 30 is shown in a raised stored position against the vehicle headliner in which a map or other flat item storage clip 36 is shown. Each of the visors 20 and 30 integral include a vanity mirror assembly 26 and a map storage clip 36, which, in turn, are integral with the mounting assemblies 40 for attachment of the pivot rod assemblies 22, 32 to the respective visor. The construction of visor 30 is shown in greater detail now with reference to FIGS. 2-5, it being understood that visor 20 is of identical but mirror image construction.
The body 75 of visor 30 is laminated in a sequential process (as described in connection with FIG. 6 below) of the structure shown in the fragmentary, broken-away cross sections of FIGS. 3-5. Referring initially to FIG. 5, there is shown the core 70 of the visor which is formed from sheets of closed-cell, semi-rigid urethane material having a density of about 2.0 pounds per cubic foot, which is thermoformed together with the remaining structure to form the laminated visor body 75, which is subsequently mounted to the backbone assembly 40 and to the vehicle by the pivot rod assembly 22. The visor body 75, thus, includes a central core 70 bound on either side by layers of hot-melt glue 72 and 74 over which there is placed layers of scrim material 76 and 78. Subsequently, the outer fabric upholstery layers 80 and 82 are placed thereon. During this assembly method, the hot-melt glue sheets 72, 74 melt and extend through the scrim material, bonding the typically foam-backed layers of upholstery material 80, 82 directly to the urethane foam core 70 during the final pressing of the visor body 75 in a visor configuration as seen in FIG. 2.
The core so-formed is employed in the visor 30, which includes a pivot rod assembly 32 having a pivot rod 21 (FIG. 2) which extends into a torque control device 23, shown schematically in FIG. 2, but can be of a construction such as shown in U.S. Pat. No. 4,500,131. The pivot rod assembly 32 also includes a conventional mounting bracket (not shown in FIG. 2) of conventional construction for attaching end 25 of the pivot rod to the vehicle roof, as shown in FIG. 1. The torque fitting 23 nestably fits within a receiving housing 41 formed in one side 42 of the split mounting member 40, which includes a mating side 44. Member 40 is integrally molded of a polymeric material such polycarbonate and includes two generally elongated sides 42 and 44 which are attached to opposite sides 71 and 73, respectively, of visor body 75 over the top edge 77 of the visor body 75.
Slide 44 includes an integrally formed mirror frame 46 for receiving therein a vanity mirror 26. Elongated, relatively thin sides 42 and 44 each include a semicylindrical pin 48' which mate to form the auxiliary mounting pin 48 for brackets 24 and 34, as seen in FIG. 1. Sides 42 and 44 are joined utilizing fastening screws 50 which extend through threaded mounting bosses 52 formed in spaced relationship on the inner surfaces of both sides 42, 44. Screws 50 extend through the visor body 75 and threadably and compressibly secure the sides 42, 44 of the mounting body 40 to each of the visor panels to complete the visor assembly with pivot rod assembly 22 being captively held within housing 41. The end walls of sides 42 and 44 include semicylindrical apertures 49 for allowing the pivot rod 21 to extend outwardly from the interior of the visor assembly so-formed. Like mirror frame 46, which is integral with side 44, the map clip 36 also is integrally formed with side 42. When assembled, as best seen in FIGS. 3 and 4, the mirror frame 46 extends closely adjacent the surface 71 of visor body 75 while the resilient polymeric material forming member 40 and integral clip 36, as best seen in FIG. 3, is mounted to allow some clearance for the storage of maps and the like under the curved tip 37 of the clip so-formed. Fasteners 50 may be self-threading screws employed in connection with polymeric material so that bosses 52 need not be threaded. The upholstered visor body 75 with its trim peripheral edge 79 is formed by the process now described in connection with FIG. 6.
Referring now to FIG. 6, there is shown a method of manufacturing the visor shown in FIGS. 1-5 which includes cutting sheets of semi-rigid urethane foam into rectangular blanks as indicated by step 90. Such blanks are somewhat larger than the overall shape of the visor core 75 when completed. Next, the adhesive material 72 and 74 is applied to opposite sides of the blanks, as indicated by step 92. This can be accomplished by supplying rolls of adhesive converging on opposite sides of the blanks as they progress along an assembly line or by spray-applying the hot-melt glue in liquid form to opposite sides of the urethane blanks. The scrim material 76, 78 is then applied to the outer surfaces of the adhesive as indicated by block 94. The scrim employed is a spun-bonded, non-woven polyester material which has a weight of 0.6 oz/yard 2 . It adds some external strength to the overall visor body construction and serves as an interface between the foam backed upholstery and the foam core. The upholstery fabric is then applied to the partially formed visor body, typically utilizing rollers from above and below the now web of blanks, adhesive and scrim, as indicated by step 96. This still loose laminate is then heated in an oven as indicated by step 98 to soften the hot-melt glue which permeates the scrim material, which step is followed by the die cutting of the final visor body shape in a 50-ton press utilizing a steel rule blade, knife edge ground, to define the peripheral edge 79 of the visor body 75, as indicated by step 100. The die cutting occurs while the hot-melt glue is molten so that the free edges 81 (FIG. 5) of the upper and lower layers 80, 82 of fabric bond together and form the trim edge 79 of the visor body 75. This process of cutting and pressing is performed while cooling the melted adhesive during a pressing and cutting cycle of approximately 30 seconds under 50 tons of cutting force which is sufficient to provide the trim tear-seal appearance to the peripheral edge 79 and allow the hot-melt adhesive to solidify bonding the upholstery evenly to the planar surface of core 70 through the permeable scrim material 76, 78. The support member 40 is then attached to opposite sides of the visor body 75 utilizing fastening screws 50 after the pivot rod assembly 22 is positioned within housing 41. This completes the assembly of the laminated visor structure of the embodiment shown in FIGS. 1-5. It is noted that the sectional views of FIGS. 3, 4, 7 and 10 show only the core scrim and upholstery since the adhesive melts and blends into the interface of these three layers. In an alternative embodiment, an organic recyclable material is employed for the visor core and is shown in FIG. 7 now described.
The visor shown in FIG. 7 is of the same general construction as that shown in the embodiment of FIGS. 1-5 and manufactured by a process similar to that described in FIG. 6 with, however, a different core material. The visor core 110 of FIG. 7 is made of a blend of organic fibrous material known as kenaf, which is the ground-up stalk fibers of a hibiscus plant. These fibers are blended with polypropylene fibers in a mixture which can range from about 40% kenaf to 60% polypropylene fibers by weight to a mixture of about 60% kenaf and 40% polypropylene fibers. The polypropylene is in a fibrous form, and the kenaf and polypropylene fibers are mixed in a conventional pin cylinder mixer as indicated by block 112 in FIG. 8 and subsequently oriented, as indicated by block 114, and formed into a web using a conventional air-lay machine to initially orient the fibers longitudinally and subsequently by a standard needling machine to entangle the fibers, as shown by block 116 in FIG. 8. The result is an approximately one-inch thick web of somewhat fluffy mat-type material which is then employed in the process shown in FIG. 6 by cutting into blanks and following the same sequences shown in FIG. 6 by which the one-inch mat becomes compressed into a sufficiently rigid form to provide a structurally rigid visor core to which the backbone mount 40 of FIG. 2 is attached to complete the visor assembly 30. Thus, the visor assembly shown in FIG. 7 is made of a relatively inexpensive previously unused material which surprisingly has characteristics which lend itself to the forming of a visor core and is an organically, ecologically acceptable substitute for the foam urethane core material shown in the embodiment of FIGS. 1-5. The polypropylene fibers likewise can be from recycled polypropylene products. The kenaf material can also be used in a butterfly-type core construction, as shown in FIGS. 9-10, utilizing a somewhat different process, as illustrated in part in FIG. 11, which visor construction and manufacturing method is now described in connection with these figures.
In the third embodiment shown in FIGS. 9-11, a butterfly-type visor core 175 is provided and formed with an integral hinge 172 between core halves 171 and 173. Each of the core halves comprise a composite material of a mixture of kenaf as in the second embodiment, together with a blend of polypropylene fibers as in the second embodiment. Alternatively, the core may be a blend of the composite material described in U.S. Pat. No. 5,068,001, the disclosure of which is incorporated herein by reference, with polypropylene fibers in the same range of ratios of about 40-60% to about 60-40% by weight. These raw materials are blended in the same proportions as described in connection with FIG. 2, as indicated by block 118 in FIG. 11, and introduced into a platen heater. Once the kenaf and blend of mating materials have been mixed, the fibrous material is again oriented as indicated by block 120 and needled into a web of material indicated by block 122 similar to that as indicated by block 114 in FIG. 8.
The web from the needling step 122 is then laminated with a trim web of 70% polypropylene and 30% polyethylene tetrafluoride (P.E.T.) on what becomes the inner surface 174 of the visor body by applying such backing material as indicated by block 124. The backing material is subsequently bonded in a heating and pressing step 126 which is achieved in a platen heated press providing 20 tons of pressure to form the rough butterfly outline, which is subsequently trimmed into the final butterfly core shape, as seen in FIG. 9 and indicated by block 128. Upholstery fabric is then applied to the pre-formed core, as indicated by block 130, in any conventional matter, or as taught by U.S. Pat. No. 4,570,990. The addition of the sheet 174 of polypropylene and polyethylene tetrafluoride blend material serves to, when pressed as indicated by block 126, laminate the material to the butterfly core so-formed and serves to subsequently, when the visor is upholstered and the core is upholstered and folded together, form the final visor, bind the visor halves together holding the upholstery in place. For such purpose, a plurality of oval lands 176 (FIGS. 9 and 10) are formed on each of the visor halves 171 and 173 to matingly align such that when the visor core halves are pressed together and heated, the land surfaces bond to mating adjacent surfaces. Prior to this, a pivot rod assembly of conventional design is inserted into end 178 (FIG. 9) of the visor core.
Such construction results in a relatively thin (3/32 of an inch) visor core utilizing, in part, an organically recyclable material which is relatively inexpensive and heretofore not used for such products. Such blend of materials provides sufficient structural rigidity and bonding ability to provide the strength necessary for the visor to accommodate not only a pivot rod assembly but, if desired, an illuminated vanity mirror assembly which can be mounted in a molded-in pocket 177 formed in, for example, side 171 of core 175. It has been discovered that the composite material which is pressed into the butterfly shape has sufficient density and rigidity that it also can be formed with pins around the periphery for holding the upholstery thereto such that the fabric need not be bonded to the butterfly core prior to closing the core halves. Thus, the edge of core 175 can include pins and mating slots such as disclosed in U.S. Pat. No. 4,763,946 around the peripheral edge 180 of the butterfly core to provide an upholstery-holding function as the core halves are folded together and the upholstery held in place by fingers in a conventional manufacturing process while the facing abutting surfaces 176 of the core halves are bonded together.
With each of the laminated form visor bodies of the present invention, therefore, a visor is provided at relatively low cost and provides a light-weight, strong and attractive visor which conforms to modern vehicle appearances. It will become apparent to those skilled in the art that various modifications to the preferred embodiment of the invention can be made without departing from the spirit or scope of the invention as defined by the appended claims. | A visor, according to one embodiment, comprises a closed-cell, semi-rigid urethane foam material thermoformed from sheets into a visor core construction with a reinforced backbone mounted along an edge thereof for mounting the visor to a vehicle. The visor is upholstered utilizing an adhesive and scrim laminate and is formed by heating, pressing and cutting to assure the outer upholstery material adheres smoothly to the visor core and provides a trim edge in appearance. According to another embodiment of the invention, a blend of kenaf fibers are employed as the core material, which is laminated with upholstery material as in the first embodiment to complete the visor construction. In yet another embodiment of the invention, a butterfly-type core construction is made of high density kenaf blend and upholstered in a manner employed for other butterfly visor core constructions. | 1 |
BACKGROUND OF THE INVENTION
This invention generally relates to connectors of the type used in the handling and administration of parenteral fluids and, more particularly, to a connector adapted to make sterile connections in medical systems without the use of a sharp cannula.
Injection sites for injecting or removing fluid from a system, such as an IV infusion set connected to a patient, or a fluid reservoir or drug vial, are wellknown and widely used. Conventional injection sites generally involve a pierceable septum formed of an elastomeric material such as latex rubber or the like, captured in an access port. The housing of the septum may be, for example, the Y-body of a conventional Y-site component of an IV delivery set. A sharp cannula is inserted into the access port, piercing the septum, and a distal end of the cannula is positioned distal of the septum. In this way a fluid connection is made with the Anterior of the access port through the inserted cannula. Upon withdrawal of the sharp cannula, the elastomeric septum reseals the puncture made by the now-withdrawn cannula. Thus a sterile environment can be maintained within the housing of the injection site. The outer surface of the septum of the injection site is wiped with an antiseptic before each use to prevent septic agents from being drawn into the access port by the piercing movement of the needle.
Recently, connectors for accommodating injection and withdrawal of fluids without the use of sharp cannulas have been used in increasing numbers instead of conventional injection sites. This is, at least in part, due to concern regarding the transmission of blood-borne diseases through accidental needle punctures of the person handling the sharp cannula. Connectors having no sharpened surfaces are desirable because the chances of inadvertently piercing the operator's skin are lessened.
However, some existing needleless connectors allow fluid flow in only one direction, or require some further manipulation after a connection is established to allow fluid flow in both directions. Both of these characteristics are undesirable because they limit the usefulness of the connector. A further concern in the design of needleless connectors is the order of occurrences in which the connection is made. For example, allowing fluid to escape or air to enter during connection due to the female connector being opened before the male connector is sufficiently seated are undesirable.
Additionally, some existing connectors accommodate a relatively large interior fluid volume, requiring injection of a commensurately large volume of fluid just to fill the connector. If not taken into account, this fluid volume can detract from the volume of medicament injected and may be clinically significant. An inconvenient separate flushing procedure may be required in low dose injections or in the injection of unstable medicines due to this relatively large interior volume.
Moreover, relatively complex geometries and provision of springs and the like in the wetted portion of the connector interior may give rise to "dead spaces", where fluid tends to linger due to poor flushing. Dead spaces give rise to problems similar to those occasioned by large interior volumes, again resulting in the inconvenient requirement of flushing.
A further concern regarding the design of a needleless connector is that it should not accommodate a conventional sharp needle. Where such connectors can be used with sharp and blunt cannulas, the deterrent effect with regard to using sharp needles to make fluid connections, with an associated reduction in the number of accidental needle sticks, is potentially compromised.
Furthermore, it is desirable that needleless connectors be configured so that they can be easily cleaned by an antiseptic wipe or otherwise sterilized prior to making a connection. All exterior surfaces that may be involved in the transmission of fluid should be available for cleaning prior to the connection being made. Some prior connectors have a small rift or fissure, defined by a clearance between parts or an elastomeric element that is not under sufficient compression, at the proximal or connecting end. Such a feature is difficult and inconvenient to clean in attempting to sterilize a connector. Alternatively, connectors requiring a cap to maintain a sterile connection port are undesirable because the extra steps of removing and replacing a cap are inconvenient for medical personnel.
Another important characteristic of a needleless connector is its ability to hold a vacuum from a distal side. That is to say, if a vacuum is applied to the interior of the connector, the connector should not admit air. This becomes an increased concern in connectors that have been used at least once. Adverse consequences may result if a connector cannot hold a vacuum, for example, some automated infusion pumps wall pull a vacuum in a tubing line under certain circumstances. Needlelees connectors that will not hold a vacuum, incorporated in an infusion get used with such a pump, may admit air when no connector or cap is attached, which may in turn cause a potentially harmful air embolism in a patient.
The ability to accommodate a high fluid flow rate is also desirable in a needleless connector. Physicians in certain situations order the administration of medicaments at high flow rates. Some prior connectors have restrictive geometries, which limit their flow capacity such that administering fluids at high rates is inconvenient for medical personnel. Often flow rate requirements cannot be met under gravity head flow conditions.
Lastly, some existing needleless connectors have a relatively complex configuration and large number of parts. Such connectors are difficult and costly to manufacture, and may have more problems in service, such as sticking due to the difficulty flushing medicaments from small dead spaces inherent in complex geometries referred to above.
Consequently, there is a continuing need, for a variety of reasons, for improvements in injection sites. The present invention fulfills this need.
SUMMARY OF THE INVENTION
Briefly, and in general terms, the invention provides a needleless connector of relatively simple design and few parts which is intuitive to use and which is relatively inexpensive to manufacture, accommodates a high flow rate, is more easily cleaned before use, and does not require a protective cap. The design minimizes unwanted fluid and air leakage, has minimal interior fluid volume and "dead space," and is not compatible with a sharp needle, thereby reducing accidental needle punctures of medical personnel.
More specifically, the connector of the invention includes a housing having first and second ends, defining a chamber therebetween, the first end defining a connection port. A blunt cannula is carried by the housing within the chamber, the blunt cannula having a fluid passage therethrough in fluid communication with the second end of the housing. An elastomeric pro-slit plunger is movably disposed in the housing in a first position within the connector. In this first position the elastomeric pro-slit plunger sealingly occludes the passage through the cannula at the proximal end of the cannula. When moved to a second position within the chamber the elastomeric pro-slit plunger is penetrated by said blunt cannula so that the first and second ends of the housing are in fluid communication by means of the passage through said blunt cannula.
In a more detailed aspect, a biasing means is included for biasing the plunger to the first position within the chamber. This biasing means is, for example, either a deformable spring-like or other elastic member, a pressurized gas within the chamber, or a combination of both.
In another detailed aspect, when the elastomeric plunger is in the first position, it is flush with the first end of the connector. The elastomeric plunger is in radial compression in this area, eliminating any annular crack or fissure that might otherwise exist between the plunger and the housing, and the slit portion is held tightly shut. As a result, there is no place for pooling of fluid or other contaminants in the outer geometry, and the connector can be easily cleaned, for example with an alcohol swipe, to sterilize it before connection. These features eliminate the need for a separate cap, and make the connector according to the invention convenient for medical personnel to use, with attendant time and cost savings. Moreover, the design reduces the chance of an infection being transmitted through the connector, and the configuration also allows the connector to hold a vacuum within the chamber without admitting outside air.
In further detailed aspects of the invention, a significant portion of the fluid pathway between the first and second ends of the connector 10, in making a fluid connection, comprises the blunt cannula 30, which has a small fluid volume associated with it. Consequently, the connector as a whole defines a flow channel therethrough that has a relatively small interior fluid volume, reducing the need for flushing. At the same time, the connector can accommodate a relatively high fluid flow rate, as the flow channel is straight and is not restricted. Dead space associated with the connector is commensurately small.
Lastly, to reduce the number of component parts, the blunt cannula can be formed unitary with the housing member. This results in three component parts being required if a two-piece housing is used.
The connector of the invention, with its simple construction and small number of parts provides manufacturing cost savings, as well as enhancing safety, reliability and ease of use in preparing medications and treating patients. These and other features and advantages of the invention will become more apparent from the following detailed description, taken in conjunction with the accompanying exemplary drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a connector embodying features of the invention;
FIG. 2 is an exploded perspective view of the connector shown in FIG. 1;
FIG. 3 is a longitudinal cross-sectional view of a needleless connector in accordance with the invention, taken along line 3--3 in FIG. 1;
FIG. 3a is a longitudinal cross-sectional view of component of a connector of the invention, taken along line 3a--3a in FIG. 2;
FIG. 4 is a longitudinal cross-sectional view of a connector according to the invention as shown in FIG. 3, showing a male fitting connected; and
PIG. 5 is a longitudinal cross-sectional view of a second embodiment of the connector of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIG. 1 for purposes of illustration, the invention is embodied in a self-sealing fluid connector of the type generally known in the art as a "needleless" connector 10, more specifically in the body of a Y-site 12. The connector is capable of receiving a compatible connector incorporating a blunt cannula, such as a male luer connector fitting 14 (with or without a luer look 16, 17) in a female luer connection port 18, displacing an elastomeric plunger 20.
When no male connector 14 is inserted, the elastomeric plunger 20 is at a first position at a proximal end of the connector, flush with the connection port 18. The well of the female connection port is completely sealed by the elastomeric plunger, and there is no opportunity for fluid to pool in the exterior geometry of the connector. This configuration also allows the connector to be easily wiped, for example by an alcohol swipe (not shown). These features reduce the chance that infectious agents will be introduced into the interior of the connector when a male connector is inserted.
The elastomeric plunger 20 is pre-slit by a single longitudinal slit 22. The slit is closed when no connector 14 is inserted into the connector 10. The elastomeric plunger is radially sized slightly larger than the connection poet 18 at its proximal end, and as a consequence, is under radial compression as it rests within the female luer connection port. The plunger can be eccentric in cross-section in this regard, the dimension where the plunger is thickest coinciding with the direction of application of pressure calculated to most effectively close the slit 22. This holds the walls of the pro-slit portion tightly together so that a seal against passage of liquids, gasses and pathogens will be formed by the elastomeric plunger in the luer connection port 18. Also, compression of the plunger at its proximal end eliminates the annular crack or fissure between the plunger and the walls of the connection port that otherwise might allow pooling of liquids or harbor pathogens. These features, combined with the proximal end of the elastomeric plunger being flush with the connector port 18 for easy sterilization, make it unnecessary to use a separate cap (not shown) to protect the connector from contamination.
In use, the connector 10 incorporated in a Y-site 12 is typically connected to flexible tubing fluid lines 24, 26 of a fluid system, Such a system might be for example an IV administration set (not shown), connected through a venipuncture site to the circulatory system of a patient.
Turning to FIG. 2, in the illustrated embodiment the needleless connector 10 is formed of three parts. The simplicity of design and small number of parts are highly advantageous in terms of reliability, ease of manufacture and use, and cost. A distal housing member 28 is formed of a resilient plastic material in this embodiment and incorporates a blunt cannula 30 which is preferably formed of the same material as the housing member 28, and is of unitary construction therewith. Alternatively, the blunt cannula could be a separate member formed of a different material, integrated into the housing member. The housing member also incorporates tubing connector portions 32, 34 for connecting to flexible tubing lines 24, 26 (FIG. 1).
A proximal connection port housing member 36 is joined to the distal housing member 28 to form the housing of the needleless connector 10. The connection port housing member 36 incorporates the female luer connection port 18 and luer lock 16 of the connector. The connection port housing member is preferably made of the same material as the distal housing member, and the two housing members are Joined by conventional methods of bonding such as ultrasonic or solvent welding, for example. As will be apparent to one skilled in the art, the two housing potions could also be made of differing materials.
After the two housing members 28, 36 are joined, the elastomeric plunger 20 is inserted through the luer connector port 18 into the joined housing members 28, 36. A Food and Drug Administration (FDA) approved silicone lubricant may be used to facilitate this process, as well as to aid in operation of the connector as discussed below. The insertion of the elastomeric plunger causes gas (such as air or another selected gas) inside the joined housing members to be pressurized. Pressure within the housing can be controlled by adjusting the speed of insertion of the plunger, and/or partially or completely occluding the tubing connectors 32, 34 whale the plunger is being inserted. After insertion of the plunger an annular stop ring 38 interacts with the proximal connection port housing member 36 to retain the plunger in the housing, and thereby maintain the pressurized state of the gas within the housing.
The elastomeric plunger 20 in the illustrated embodiment also has a proximal seal portion 39 which provides a seal against contaminants, and radial compression of the plunger where it incorporates the slit 22 at the proximal end as discussed above. The plunger also includes a cylindrical sleeve portion 40. The plunger is preferably formed of a self-lubricating silicone rubber in this embodiment which is impregnated with an FDA approved silicone lubricant. Alternatively, an elastomeric material having similar properties could be used, in combination with an FDA approved silicone lubricant conventionally applied. During assembly, the cylindrical sleeve portion is guided into correct position by the blunt cannula member 30 which it fits over.
Turning to FIG. 3, the interaction of the various members 20, 28, 36 in the assembled connector 10 can be seen more clearly. The plunger 20 is at a first position within the assembled housing 28, 36 wherein the connector is closed and sealed. A cylindrical blunt cannula receiving portion 41 is formed in the interior of the plunger, and is sealingly disposed about the first or proximal end of the blunt cannula 30. The cylindrical blunt cannula receiving portion and the pro-slit portion 22 of the plunger are connected by a transition portion 37. The blunt cannula receiving portion can be configured to have different diameter segments along its longitudinal dimension. For example, a distal relieved portion 33 which is not compressed against the blunt cannula when the plunger is in its first position has a larger diameter than the rest of the blunt cannula receiving portion 41. This is more clearly shown in FIG. 3a. The relieved portion allows easier movement of the plunger over the blunt cannula.
The elastomeric plunger 20 also incorporates a relived portion 35 on its outer circumferential surface between the annular stop ring portion 38 and the proximal seal portion 39. This portion is under less radial compression than that at the location of the slit 22 and the proximal seal portion. Silicone lubricant, if applied to the outer surface of the plunger, may be retained between the proximal seal portion and the annular stop ring 38 in the assembled connector 10. Due to these considerations, friction is reduced and movement of the plunger within the connector is improved.
Returning to FIG. 3, an outer sealed chamber 42 is formed within the distal housing member 28 between the cylindrical sleeve portion 40 of the elastomeric plunger 20 and the housing walls. An inner sealed chamber 43 is formed between the cylindrical sleeve portion and the blunt cannula member 30. As mentioned, gas within these chambers may be pressurized upon assembly of the connector.
The blunt cannula 30 in the illustrated embodiment has a cylindrical base portion 44 which carries a distal end 46 of the cylindrical sleeve portion of the elastomeric plunger 20. The interior of the blunt cannula is in fluid communication with, and forms an extension of, a fluid conduit 48. The fluid conduit 48 may be placed in fluid communication with an external fluid delivery system, such as an IV administration set connected to, a venipuncture site in a patient (not shown) byway of a passageway 49 through the Y-site 12. The fluid conduit 48 and cannula 30 form a fluid pathway which is closed at its proximal end by the plunger 20 when the plunger is at a first position at the proximal end of the connector 10.
The elastomeric plunger 20 is partially penetrated in this embodiment by the blunt cannula member 30 through the blunt cannula receiving portion 41 when the elastomeric plunger is in the first position as discussed above, and the plunger is biased to this position by a force caused by pressurized gas in the sealed chambers 42 and 43. The plunger is also biased to the first position by a force produced by the cylindrical sleeve portion 40 of the elastomeric plunger seeking its un-deformed shape. In an alternate embodiment, a spring or the like could be substituted for the cylindrical sleeve portion to produce a biasing force in a similar manner. These forces push the plunger against the connection port housing member 36. The distal end of the connection port housing member 36 forms an annular ledge 50, on which the annular stop ring portion 38 of the elastomeric plunger 20 catches, to retain the plunger in the connector 10.
The configuration of the connector 10 when the elastomeric plunger 20 is in the first, or sealed, position allows it to maintain a seal against both positive and negative pressures. If a vacuum is drawn within the connector, the sides of the transition portion 37 and, consequently, the pro-slit portion 22 are drawn more tightly together to form a tighter seal. This is advantageous in applications where a vacuum may be present in a connected fluid line, for example in and IV system (not shown) that includes an automated infusion pumping device, so that no air is drawn into the IV system through the connector 10.
Referring to FIG. 4, when a male luer fitting 14 is inserted into the female luer connection port 18, the male luer fitting first contacts the proximal end surface 52 of the elastomeric plunger 20, forming a fluid-tight seal as the male luer fitting is advanced into the female connector port 18 against the biasing force described herein. This acts to eliminate fluid leaks from the needleless connector 10 during connection of a male luer fitting, and helps prevent the introduction of pathogens into the connector.
Insertion of the male luer fitting 14 moves the elastomeric plunger 20 dietally to a second position, and further pressurizes gas within the sealed chambers 42, 43. Insertion also causes elastic deformation of the cylindrical sleeve portion 40 of the elastomeric plunger, giving rime to a restoring force. The biasing force on the plunger caused by these two consequences of connection urge the plunger tightly against the inserted male luer fitting.
As can be appreciated with reference to the illustrated embodiment, when the male luer fitting 14 is fully inserted and the elastomeric plunger 20 is moved to its second position the proximal surface 52 of the plunger is positioned distally of the proximal end 54 of the blunt cannula 30. The blunt cannula extends into the inserted male luer fitting 14. To open the connector 10 for injection or withdrawal of fluid through it, the proximalend 52 of the plunger need only be pressed to a position distal to the proximal end of the blunt cannula so that the pre-slit portion 22 of the plunger does not cover the cannula 30 opening. It is apparent from FIG. 4 that the connector will accommodate a range of male luer fitting sizes and yet allow proper positioning of the proximal end of the plunger in operation. The configuration allows considerable leeway in this regard. However the biasing force will be greater with deeper penetration of the luer fitting, due to greater deformation of the elastomeric sleeve 40, and greater compression of the gas in chambers 42 and 43.
The male luer fitting 14 is held in the female luer connection port 18 of the connector 10 by friction fit, or by means of luer lock fittings 16 and 17. With a male luer fitting 14 inserted, a fluid pathway is opened from the male luer fitting through the interior of the blunt cannula 30 and fluid conduit 48 to a passageway 49 in fluid communication with a system (not shown).
As will be apparent, the connector 10 has a very small interior fluid volume. The conduit 48, and its extension through the blunt cannula 30, are of relatively small cross-sectional area and length. Furthermore, dead space is minimized because the plunger 20 is sealingly pressed against the tip of an inserted male luer fitting 14 and only moves inwardly as far as the male connector is inserted. For example, in FIG. 4, the only dead space is the volume between the outer diameter of the blunt cannula and the inner diameter of the inserted male luer fitting in the small distance the male luer fitting 14 extends beyond the opening of the blunt cannula 30. Moreover, there are no springs, complex conduit arrangements, or the lake, in the flow stream. A spring used in place of the elastomeric sleeve portion 40 would also be disposed outside of the blunt cannula and therefore outside of the wetted portions of the connector. Consequently, the fluid pathway through the connector is small in terms of fluid volume, but is straight and unobstructed. The connector as a result is easier to prime, and is advantageous in administration of low volumes of medications, due to the small fluid volume required to fill the connector and the inherent flushing action resulting from the design. Nevertheless, it has been found that the connector accommodates a relatively high flow rate, in both gravity and pumped flow applications.
During withdrawal of the male luer fitting 14, the elastomeric plunger 20 moves distally toward its first position, and its proximal surface 52 stays in sealing contact with the male luer fitting being withdrawn, due to the biasing forces acting on the plunger. As mentioned the biasing forces are the result of compressed gas within the chambers 42 and 43 and the elastomeric sleeve 40 seeking its un-deformed shape. Lubricant facilitates movement of the plunger.
Thus a fluid seal is maintained between the male luer and the plunger until the plunger has returned to its first position, and the fluid pathway through the connector then closed. As with connection, this sealing action minimizes fluid leakage during disconnection and helps maintain an a-septic condition within the connector.
As can be appreciated with reference to FIGS. 3 and 4, another feature of the connector 10 is that while it allows a large blunt cannula such as a male luer fitting 14 to be connected, it will not accept a sharp needle (not shown). Due to the placement of the proximal end 54 of the blunt cannula 30 in the female connection port 18, a needle inserted into the elastomeric plunger 20 when it is in the first position as shown in FIG. 3 will likely catch on the blunt cannula, discouraging the attempt to insert a needle. Should a needle get past the blunt cannula 30, any attempt to inject or withdraw fluid wall be frustrated, as the needle would then be in one of the closed chambers 42 or 43 within the connector. Incompatibility with sharp needles reduces the likelihood of their attempted use with the connector, and reduces commensurately the risk of accidental needle punctures of users.
The needleless connector 10 of the invention has been shown embodied in a Y-site 12 in FIGS. 1-4, but the connector may be incorporated in other kinds of medical fluid handling and delivery apparatus. As an example, an alternate embodiment is shown in FIG. 5, where the needleless connector is incorporated in an adapter fitting 60 which can be attached to a standard female luer fitting (not shown) to provide a self-sealing needleless connector. The operation of the needleless connector is the same in this embodiment as that previously described. However, instead of a fluid pathway through the blunt cannula 30 and fluid conduit 48 opening into a Y-Site, the fluid conduit is in fluid communication with a standard male luer connector 62. A distal housing member 64 incorporates a luer lock 66.
From the above, it is evident that the present invention provides an advantageous needleless connector 10 constructed of relatively few parts, which is simple and reliable in operation, and can be manufactured at a relatively low cost. At the same time, the connector according to the invention allows safer and more convenient needleless handing and infusion of IV fluids in preparing medications and the treatment of patients. It is simple and intuitive to use, and further, provides advantages in sealing characteristics, low dead space and fluid volume, and improved flushing characteristics.
While several particular forms of the invention have been illustrated and described, it also will be appreciated that various modifications can be made to the present invention without departing from the spirit and scope thereof. | A needleless connector allowing infusion and withdrawal of fluid in medical applications is disclosed. The injection site has a housing which contains a blunt cannula within it. An elastomeric pre-slit plunger is movably carried within the housing by the housing and said blunt cannula. Insertion of a connector moves the elastomeric pre-slit plunger from a first, occluding position deeper into the housing and over the blunt cannula to a second position, where the pre-slit portion of the plunger is penetrated by the blunt cannula. This opens a fluid passage from the inserted connector through the cannula to the opposite end of the housing, allowing fluid flow through the connector. Pressurized gas within the housing, or an elastically deformable member, or the two in combination, bias the elastomeric plunger back to its first position. As an inserted connector is removed, the fluid pathway through the injection site is re-sealed. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a device utilizing a sputtering cathode for masking or covering substrates, the device having a center mask guide element on which a center mask, which covers the substrate, is disposed and works together with an outer mask in such a way that only the uncovered part of the substrate is coated during the coating process.
A device for cathode sputtering of disk-shaped substrates of the type mentioned at the outset is disclosed in DE 43 15 023 Al, Cl. C 23 C 14/35. This device generates a plasma in a vacuum or process chamber provided with at least one opening which can be closed from the outside by placing a sputtering cathode on it, wherein an elastic seal ring is provided between the cathode and a chamber wall. It is possible to mask a compact disc (CD) at its inner and outer diameters with this device, so that only defined portions of the surface of the CD are coated. It is intended to coat defined surface areas of the CD by means of this device in such a way that a well defined boundary between the coated surface areas and the uncoated or metallized surface areas of the CD is achieved. To this end the CD is pressed against the outer and inner edges of the inner and outer masks. The necessary simultaneous pressing against two different components is complicated and difficult because of height differences and requires very tight manufacturing tolerances.
GB-A-2286201 discloses a magnetron sputtering apparatus with an inner and an outer mask with a common alignment with respect to the CD.
BRIEF SUMMARY OF THE INVENTION
Accordingly an object of the invention is to provide a device which enables distinctly defined surface areas of a CD to be coated in such a way that a well defined boundary between the coated surface areas and the uncoated or metallized surface areas of the CD is achieved, wherein the substrate or the CD is adjusted in such a way that height differences can be easily compensated.
This and other objects are attained in accordance with the invention in that the inner and/or the outer masks can be adjusted independently of each other. Since it is possible to adjust the inner and outer masks of the sputtering cathode independently in respect to the substrate, they can be pressed against the surface of the substrate with an even contact pressure, so that exact and defined surfaces are created which are not coated by cathode sputtering. By means of the even contact pressure of the two masks it is achieved that no coating material gets underneath the masks or into the space between the underside of the masks and the surface of the substrate or the CD.
In this way it is also possible to compensate manufacturing tolerances to a large extent, so that even with masks of different lengths the two masks are located on the same transverse plane in their final position, i.e. when they rest on the surface of the substrate.
It is furthermore advantageous that the inner, or center, mask can be adjusted independently of the outer mask in the device for coating the substrate as a function of the gas pressure. By means of the employment of the gas pressure prevailing in the device, it is possible to adjust the center mask in the direction of the substrate, so that the substrate is used in a compulsory manner for adjusting the center mask always at the time when the substrate is moved in the direction of the masks. By means of the individual adjustment of the center mask it is also possible to initially move the center mask in the direction of the surface of the substrate, or the center mask can be moved into a position in respect to the outer mask in which the center mask slightly protrudes in relation to the outer mask. By means of this it is assured that first the center mask comes to rest against the surface of the substrate, which then, in the course of adjusting the substrate in the direction of the center mask, subsequently also comes to rest against the outer mask, so that then both masks create a surface which can be exactly defined and is freed for coating.
In accordance with a further development of the device of the invention there is an additional option that, independently of the outer mask, the center mask can be adjusted in the device as a function of the differential pressure in the direction of the substrate and/or in the direction of the longitudinal center axis of the device or the cathode. It is possible in a cost-effective manner to employ the differential pressure for adjusting the center mask in relation to the surface, so that additional adjustment members can be omitted. In this way it is assured that the center mask always is the first to come to rest against the surface of the substrate. If the substrate is further adjusted upward or in the direction toward the two masks, the outer edge of the substrate subsequently comes to rest against the outer mask. By means of this an even contact pressure of both masks against the surface of the substrate is achieved.
In further development of the invention it is advantageous that the differential pressure force F dif in the device is determined by the exterior diameter of the adjustable portion of the holder which is arranged coaxially with the longitudinal center axis of the cathode.
In accordance with a preferred embodiment of the attainment of the object of the invention it is finally provided that the differential pressure diameter P d is situated in the area of a diaphragm or is determined by the inner diameter of the diaphragm in the assembled state which seals the vacuum chamber of the device against the chamber in which the atmospheric pressure prevails, and that the center mask consists of a plate-shaped mask element which is disposed on a cylinder-shaped cooling housing, the latter being arranged on the center mask guide element or a cantilever arm and being adjusted by means of the latter in relation to the differential pressure.
It is of particular importance for the instant invention that the plate-shaped center mask element can be adjusted between two adjustable stops dependently or independently of the adjustment path of the cantilever. It is possible by means of the independent adjustment of the plate-shaped center mask element in relation to the outer mask element to use the differential pressure as an adjustment device for the center mask element, so that separate adjustment elements for adjusting the center mask element and for assuring an even contact pressure of both mask elements can be omitted.
It is furthermore advantageous that the plate-shaped mask center element is releasably connected with the cylinder-shaped housing or the cooling housing, is disposed concentrically in respect to the longitudinal center axis and is releasably coaxially connected with the cooling housing.
To this end it is advantageous that the cooling housing is releasably connected to the center mask guide element and its adjusting movement can be limited by at least one stop. The lift path of the center mask is limited by the adjustably embodied stops and damage to the diaphragm is prevented in this way.
In accordance with a further development of the device of the invention there is the additional option that the center mask guide element can be adjusted between two stops and that the stops are adjustable.
It is advantageous in a further embodiment of the invention that the stops are disposed on the center mask guide element or on a cantilever arm which receives the center mask guide element, and that the diaphragm, the cooling housing and/or the center mask seal the chamber with atmospheric pressure P a in respect to the chamber with the vacuum pressure or the vacuum chamber.
It is achieved in this way that the diaphragm consists of a cylinder-shaped element or center piece, to the ends of which respectively one flange is connected which is releasably received in respectively one clamping device, that the center mask can be adjusted in relation to the clamping device or the nonadjustable elements of the device or the outer mask, and that in the initial position, in which the masks are disposed at a distance from the surface of the substrate, the center mask protrudes in respect to the surface of the outer mask in such a way that the center mask comes first to rest on the surface of the substrate when the latter is moved in the direction toward the center mask.
A further advantage is that the outer mask and/or the lower part of the center mask are releasably connected and the outer mask and/or the lower part of the center mask come to rest against the surface of the substrate with approximately the same contact pressure.
It is furthermore advantageous that the center mask guide element, the cantilever arm or the element which guides or adjusts the center mask guide arm are provided in a chamber which is continuously under an atmospheric pressure P 1 .
Further advantages and details of the invention are described below and illustrated in the drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is a cross-sectional, elevational view of a device according to an embodiment of the invention having a sputtering cathode and an individually adjustable center mask.
FIG. 2 is a cut-away, perspective view of a diaphragm used in the device of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
A device for coating substrates, such as CD 27 is represented by 1 in the drawings, part of which device is a sputtering cathode 2.
The sputtering cathode 2 has been placed on a chamber wall 70 which, according to the drawings, is fixed in place. A ring- shaped groove 71 for receiving a vacuum seal 3 is present in the chamber wall 70. The chamber wall 70 has a circular opening 72, into which an outer mask 4 and a center mask 26 can extend.
The sputtering cathode 2 consists of a disk-shaped ferromagnetic yoke 5 and a cooling plate 7. A disk-shaped insulator 6 is inserted between the yoke 5 and the cooling plate 7. The yoke 5 as well as the cooling plate 7 are surrounded by a pole shoe 82, which is releasably connected with the yoke 5 by means of threaded bolts 73, one of which is visible in FIG. 1.
Referring to the drawings, a target 8 which is to be a sputtering source is located below the cooling plate 7 and is inserted into an annular chamber enclosed by the pole shoe 14 and is indirectly secured in the cooling plate 7 by means of a screw element or a female screw 20.
Ring-shaped grooves for ring magnets 9 and 9' are also provided on the rear of the cooling plate 7. The yoke 5, the insulator 6 and the cooling plate 7 are held together by a screw 10, wherein the screw 10 is insulated from the yoke 5 by an insulator 86 and is connected with a sputtering current supply device, not shown, by means of a cable, not shown in the drawings.
A ring magnet 13 with the associated pole shoe 14 is situated in the area of the outer, radially extending front face of the yoke 5.
As can be further seen in the drawings, an axial bore 74 is provided in the interior area of the cathode 2 and extends from the rear of the yoke 5 to as far as the front of the target 8. A center mask 26 (center anode) with an adjoining cooling housing 61 is located in this axial bore 74. Cooling housing 61 is hollow and has a center bore. A cooling line 76, which is provided with a connector 76', is housed in the center bore. Cooling water can enter through the connector 76' and the line 76 provided in the bore 75 of the cooling housing 61 and can then be removed to the outside via an annular passage, defined between the cooling line 76 and the center bore 75 of the cooling housing, and an outlet opening 78.
The cooling housing 61 which extends through the bore 74 is connected in its upper area with each cantilever arm 63 (a second parallel cantilever arm is not shown) by means of threaded bolts 80 and can be adjusted by a screw 12 forming a lower stop in the direction of a longitudinal center axis 58. A threaded coupler 77 connects the cooling line 76 and connector 76' to the housing 61. The two cantilever arms 63 are arranged in parallel and integrally connected to the upper area or head of the cooling housing 61. Depending on the weight of the device, a single cantilever could be also sufficient.
A chamber 55, which is under atmospheric pressure P a , is sealed against a vacuum chamber 54. Sealing is effected, among others, by the cylindrical cooling housing 61 and a diaphragm 59. Diaphragm 59 is shown in FIG. 2 and consists of a hollow cylindrical element or center piece 64 and two annular flanges 65 and 66 fixed to, or integral with, respective end of center piece 64. The flanges 65, 66 extend at right angles in respect to the center piece 64 and are secured in place by means of clamping devices 67 and 68, as shown in FIG. 1. The upper clamping device 67 rests against a front face 83 of the cantilever arm 63, and the lower clamping device 68 rests against a holder 84; the clamping device 68 and the holder 84 are connected by means of a screw 79 and a further screw with the yoke 5. Clamping device 68 is connected with the holder 84 by means of threaded bolts 79. The upper clamping device 67 is connected with the cantilever arm 63 by means of threaded bolts 80. By means of this the upper chamber 55 is sealed against the vacuum chamber 54. Further sealing elements 81, 81' are located in corresponding annular grooves provided in the sputtering cathode 2, and specifically in insulator 6.
The cantilever arms 63 are indirectly disposed on the yoke 5 each by means of a fixed slide column 15 and a slide bearing 82, each of which is fixed to the respective cantilever arm 63 and movable along the respective column 15, so that the cantilever arm, 63 can be displaced upwardly or downwardly in the direction of the arrow 85. The displacement path of the cantilever arm 63 as well as the center mask 26, which is vertically movable with the cantilever arm 63, extends between an upper stop 62 and the lower stop 12. The upper stop 62 consists of a screw 87 with a stop plate, screw 87 being screwed into the upper end of slide column 15. The lower stop 12 is formed by a fastening screw with a locking nut, the fastening screw extending through the cantilever arm 63 and coming to rest against the top of clamping device 68, or more specifically the top of screw 79. The adjustment path of the center mask 26 and the associated cooling housing 61 as well as of the cantilever arm 63 thus is limited by the two stops 62 and 12 and is located in the range of longitudinal stretching of the diaphragm 59, so that damage to the diaphragm 59 by movement between the two stops is prevented.
If atmospheric pressure P a prevails in the upper chamber 55 and an underpressure, or a pressure lower than the pressure P a , prevails in the vacuum chamber 54 including the sputter chamber between the cathode 8 and substrate 27, a differential pressure force F dif (see cylinder portion 64' of the cooling housing 61 contacting the inner surface of the center piece 64 of the diaphragm 53) is generated, which is determined by an annular surface 17 which results from the exterior diameter of the cooling housing 61 in accordance with the drawings. The differential pressure force F dif therefore causes an adjustment movement of the center mask 26 in the direction toward the surface of a substrate 27. The adjustment path of the center mask 26 has been selected to be such that in the initial position, in which the masks are arranged at a distance from a surface 69 of the substrate 27, the front face 19 of the center mask 26 protrudes below the surface or front face 18 of the outer mask 4 in such a way that the center mask 26 comes to rest first on the surface 69 of the substrate 27 when the substrate 27 located on a vertically movable carrier 88 is moved towards the center mask 26. During said movement of the carrier 88 (see the arrow 89), the substrate 27 centered on the carrier 88 by means of the pin 90 engaging the center hole 91 of the substrate 27, contacts the center mask 26 and, subsequently, the substrate 27 acts against the adjusting pressure or the differential pressure force F dif and displaces the center mask 26 upward until the edge area of the CD or the substrate 27 comes to rest against a front face 18 of the outer mask 4. In the course of an upward lifting movement of the substrate 27, an approximately equal contact pressure at both masks and thus defined cover areas, which cannot be coated, are generated on the surface of the substrate 27 because of the advantageous arrangement of the outer mask 4 and the center mask 26.
Although not shown in the drawings, there is also the option to mount the outer mask for vertical adjustment in a similar manner.
To this end, in the exemplary embodiment the center mask 26 is formed by a plate-shaped mask element 60, which is releasably disposed on the cylinder-shaped cooling housing 61, housing 61, in turn, being disposed on a center mask guide element 56. The cantilever arm 63 is part of the center mask guide element 56.
As can be seen from the drawings, the plate-shaped mask element 60, or a lower part 26' of center mask 26, can be releasably connected with the cylinder-shaped housing or the cooling housing 61, as by a threaded shank, so that the plate-shaped mask element 60 can be replaced at any time, for example if it has been coated with aluminum.
In an advantageous manner the plate-shaped mask element 60 is disposed here concentrically with the longitudinal center axis 58 and with the cooling housing 61.
The cooling housing 61 can also be releasably connected with the center mask guide element 56.
It is also possible for the outer mask 4 to be releasably connected with the chamber wall 70.
It is furthermore also advantageous to embody the cantilever arm 63, the center mask guide element 56, the cooling housing 61, the diaphragm 59 with its clamping devices 67, 68, the holder 84 as well as the two slide columns 15 as a pre-assembled structural component, which is releasably connected by means of the screw 87 with the yoke 5. Because of this there is the possibility of providing a horizontal adjustment in respect to the yoke 5 after the screw 87 has been loosened and the concentricity of the center and outer masks has been achieved. By means of this the center axis 58 of the diaphragm 59 is always kept constant in relation to the center axis of the component, since the diaphragm 59 is integrated in the structural component.
This application relates to subject matter disclosed in German Application number 196 14 600.3, filed on Apr. 13, 1996, the disclosure of which is incorporated herein by reference.
While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.
The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A device including a sputtering cathode 2 and masks for masking or covering portions of a surface of a substrates 27, having a center mask guide element 56 on which a center mask 26, which covers the substrate 27, is disposed and works together with an outer mask 4 in such a way that only the uncovered part of the substrate 27 is coated during the coating process. The inner and/or the outer masks 4, 26 can be adjusted independently of each other along a longitudinal center axis 58 of the device. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of, Provisional Patent Application Ser. No. 60/923,777, filed on Apr. 17, 2007, the entire disclosure of which is hereby incorporated by reference herein.
TECHNICAL FIELD
[0002] The present invention relates to a medical syringe for the withdrawal of medication from medication bottles and injection of medication into patients via medication tubing systems, and more particularly switching between a needle interface for withdrawal of medications from medication bottles and a needleless interface for injecting the medicine into a tubing system.
BACKGROUND OF THE INVENTION
[0003] Currently, certain medical treatments require caregivers to place themselves at risk of needle stick, because of the requirements of working with needles and patient bodily fluids. Recent technological improvements have been safety focused and have lessened this risk with the trend toward needleless tubing systems and procedures involving retractable needles in catheters. Existing systems, however, continue to require caregivers to use a needle to draw medication from medication bottles and then convert this needle/syringe system to a needleless system by removing the needle. In addition to the safety concerns, caregivers must locate and open two different packages, attach the needle to the syringe, draw up medication, remove the needle, then attach the syringe to the needleless tubing system and inject the medication, and occasionally repeat the process.
[0004] One known system utilizes a plastic needle-like system that can both puncture a medication bottle and access tubing systems by a puncture of the tubing system hub. This system utilizes a sharp point, like standard needles, and must be pushed into the needleless port. Inherent in this action is the risk of missing the port and sticking yourself with the device. The avoidance of this risk is the primary driver for innovative products in safer needleless systems. Moreover, the puncture of needleless hubs with needles or pointed plastic pieces may result in the creation of a leak in the tubing system and allow backflow of fluid out of the punctured hub.
[0005] Some of the newer syringe devices focus on minimizing needle sticks by having a blunt cannula attached to the syringe that is used to puncture the bottle. The cannula is removed after the medication is drawn up and a sharp needle is attached. This device does add a layer of additional protection, but is inefficient, because the cannula must be removed and a needle attached.
[0006] A second problem with newer safety systems is their potential lack of intercompatibility. For example, a nurse may draw up the medication with one system for an intramuscular injection. If the physician changes her mind and orders the medication be given intravenously, the syringe holding the medicine may be incompatible with intravenous injection system.
SUMMARY OF THE INVENTION
[0007] The present invention speeds the process, adds a layer of safety, and allows rapid conversion between a needle/syringe system and a needleless/syringe system, thus allowing an operator to move seamlessly between both systems while minimizing needle stick risk. In particular, the current invention provides for the insertion of the syringe into the needleless system with no exposed sharp point that may inadvertently lead to a skin puncture.
[0008] The system allows for a collar or sheath with an attached fluid port to slide over the fixed needle at the end of the syringe and reversibly lock in an advanced position creating a functionally needleless adaptor for interfacing with the needleless tubing systems. The system also allows for retraction of the collar to expose the fixed needle at the end of the syringe for puncturing medication bottles.
[0009] In use, the operator starts with the collar in a retracted position such that the needle is exposed, which allows the operator to puncture a medication bottle with the needle of the syringe. The operator then pulls back on the syringe plunger drawing medication through the needle and into the barrel of the syringe. When the correct amount of fluid has been drawn into the syringe barrel, the needle is withdrawn from the medication bottle. The operator then slides the collar forward and locks it in an advanced position that simultaneously covers the end of the needle and presents a needleless fluid port (e.g., a luer lock fitting) for interfacing with a tubing system. The operator can then connect the syringe to the needleless tubing system (e.g., by screwing the luer lock fitting to a corresponding fitting on the tubing system) and administer the medication by advancing the syringe plunger.
[0010] In one aspect, the invention relates to a syringe system including a syringe barrel defining an interior space, a syringe plunger slidably disposed within the syringe barrel, a needle coupled to a distal end of the syringe barrel and in fluid communication with the interior space, a collar slidably disposed about the syringe barrel, and a fluid port disposed at a distal end of the collar. The collar can be coupled to the syringe barrel to prevent inadvertent disengagement therefrom. The fluid port is configured to interface with a needleless tubing system.
[0011] In another aspect, the invention relates to a syringe system including a syringe barrel defining an interior space, a syringe plunger slidably disposed within the syringe barrel, a needle coupled to a distal end of the syringe barrel and in fluid communication with the interior space, a collar threadedly engaged with the syringe barrel, and a fluid port disposed at a distal end of the collar, the fluid port configured to interface with a needleless tubing system. The collar can be moved along the length of the syringe barrel by rotational movement thereof.
[0012] In various embodiments of the foregoing aspects, the collar is configured to slide longitudinally along at least a portion of the syringe barrel. The collar can be secured in a first, retracted position exposing the needle and a second, advanced position encapsulating the needle. In the advanced position, the fluid port is presented for interfacing with the needleless tubing system. The fluid port can include threads and be secured to the needleless tubing system by a screw action (i.e., rotation of the port, collar, and/or syringe). In one embodiment, the fluid port is a luer lock type fitting, either male or female to suit the particular application. In addition, the collar can be locked in at least one of the first position and the second position, either reversibly or irreversibly. The syringe system can include a locking mechanism disposed on at least one of the syringe barrel and the collar for locking the collar in the first, retracted position and/or the second, advanced position. In one embodiment, the collar only locks in the advanced position. Additionally or alternatively, the collar can be locked in place by, for example, frictional engagement or with the use of an O-ring.
[0013] In additional embodiments of the syringe system, the syringe barrel can include at least one slotted rail disposed on an outer surface of the syringe barrel and oriented longitudinally along a length of the syringe barrel and the collar can include at least one protuberance disposed on an inner surface of the collar for engaging the slotted rail. The collar is configured to slide along the syringe barrel via engagement of the protuberance and the slotted rail. In one embodiment, two longitudinal rails can be disposed on the syringe barrel on opposite sides thereof, e.g., 180 degrees apart on a cylindrically shaped syringe barrel. Alternatively, more that two rails can be included depending, for example, on the size of the syringe. In one embodiment, the longitudinal rail includes a transverse portion extending from a distal end of the longitudinal rail. The transverse portion of the slotted rail allows guided, rotational movement of the collar when in the second position. Alternatively or additionally, the longitudinal rail can include a transverse portion extending from a proximal end of the longitudinal rail to provide guided, rotational movement of the collar when in the first position.
[0014] Furthermore, the locking mechanism can be disposed on the transverse portion of the rail and the collar engages the locking mechanism when rotated in the second position. In one embodiment, at least one of the transverse portions of the slotted rail includes a locking mechanism for securing the collar in at least one of the first position and the second position when the collar is rotated, such that the protuberance engages the locking mechanism. In another embodiment, the syringe system includes a second locking mechanism disposed near the proximal end of the longitudinal rail. The second locking mechanism configured to secure the collar in the first position. The locking mechanism in one embodiment can reversibly lock the collar in its position by frictional engagement between the protuberance and the rail. In another embodiment, the locking mechanism includes a projection that prevents the return rotational movement of the collar by blocking the protuberance. For example, the locking mechanism can be an inclined block that allows the protuberance to slide over the inclined surface, but is blocked by a vertical wall of the block when the operator attempts to rotate the collar into an unlocked position.
[0015] In still further embodiments of the syringe system, the collar is guided between the first position and the second position by a thread disposed on an external diameter of the syringe barrel, for example as opposed to sliding on the rails. The fluid port can be configured for attachment of a secondary needle, for example, by threaded engagement. The secondary needle can provide a different needle configuration and/or size for a particular application and can be attached to the syringe in its extended position. In addition, the collar can be biased in at least one of the first position and the second position to prevent the inadvertent movement of the collar when in use. In one embodiment, the collar includes a spring mechanism for biasing the collar in the second position. For example, the spring mechanism can be a spring or other resilient member disposed within the collar between a distal end of the syringe barrel and a distal interior end of the collar, thereby biasing the collar in the second, advanced position. The collar can be forced back against the spring to the first, retracted position and locked in place. Such an arrangement will fail safe with the collar in the advanced position, thereby covering the needle.
[0016] Moreover, the fluid port may conform to at least one of ISO standard 594-1 and 594-2. The collar can be removable from the syringe barrel and interchangeable with a second collar with an alternative fluid port. This arrangement allows the syringe assembly to be customized for the particular needleless tubing system to which it will interface. In one embodiment, the collar can be snap fit onto the syringe barrel and can be removed by flexing the collar such that the protuberance(s) are moved out of the slotted rail(s). Once the protuberances clear the slotted rail, the collar can be rotated and slid off of the syringe barrel. In another embodiment, a distal portion of the collar can include an internal channel for receiving at least a distal portion of the needle. The channel can be formed in the distal end of the collar or can include an additional cylindrical body formed coextensively with the collar and defining the channel running therethrough. The needle can be moved through the channel when the collar is retracted into the first position. The collar can further include an O-ring disposed in an annular groove formed in an internal surface of the channel. The O-ring provides a seal between an outer diameter of the needle and an inner diameter of the channel for the passage of a fluid between the syringe barrel and the needleless tubing system, without leakage. The seal facilitates generating a suction at the distal end of the collar when the collar is in the extended position and the syringe plunger is drawn back to draw fluid into the syringe barrel. Generally, the syringe plunger can be extended and retracted to draw in and dispense fluid, respectively, through the distal end of the collar through the fluid port between the syringe and the needleless system. In one embodiment, the friction between the O-ring and the needle will prevent or at least impede movement of the collar. Additionally, in an embodiment where the needle expands at its base, the increased interference fit between the outside diameter of the needle and the inside diameter of the O-ring will further secure the collar in place.
[0017] In yet another embodiment of the syringe system, the syringe barrel has a generally circular cross-sectional shape and the collar has a generally elliptical internal cross-sectional shape, which provides for a slight interference between the outside diameter of the syringe barrel and the inside surface of the collar. This arrangement can provide sufficient surface tension between the collar and syringe barrel to prevent sliding movement between the collar and the syringe barrel. A light pressure can be applied to the collar to deform the internal cross-sectional shape of the collar from generally elliptical to generally circular and of a larger diameter than the outside diameter of the syringe barrel to enable slidable movement therebetween. For example, the operator applies a squeezing force to the collar with one hand to deform the collar and initiates sliding of the collar with the other hand, thereby sliding the collar along the syringe barrel between the first and second positions. When the force is removed, the collar returns to the generally elliptically shaped internal cross sectional shape which provides a partial interference fit with the outside diameter of the syringe barrel, which provides sufficient surface tension to prevent movement of the collar.
[0018] These and other objects, along with advantages and features of the present invention herein disclosed, will become apparent through reference to the following description, the accompanying drawings, and the claims. Furthermore, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the following description, various embodiments of the present invention are described with reference to the following drawings, in which:
[0020] FIG. 1A is a schematic plan view of a syringe system in a retracted or needled position in accordance with one embodiment of the invention, the syringe system including a syringe barrel, a plunger, a needle, and a sliding collar;
[0021] FIG. 1B is a schematic plan view of the syringe system of FIG. 1A , with the collar and plunger removed;
[0022] FIG. 2 is a schematic plan view of the syringe assembly of FIG. 1A in partial cross-section, with the collar in an advanced position such that the needle is covered and a fluid port on the collar may engage a needleless system;
[0023] FIG. 3 is a schematic enlarged view of the fluid port portion of the collar of the syringe system of FIG. 2 ;
[0024] FIG. 4A is an enlarged schematic cross-sectional view of the collar of FIGS. 1-3 ;
[0025] FIG. 4B is an enlarged schematic view of the distal end of the barrel of FIGS. 1-3 rotated 90 degrees;
[0026] FIGS. 5A and 5B are schematic perspective views of a syringe system in accordance with one embodiment of the invention;
[0027] FIG. 6 is a schematic exploded view of a syringe system in accordance with one embodiment of the invention;
[0028] FIGS. 7A and 7B are schematic cross-sectional views of a syringe system in accordance with one embodiment of the invention with a spring that biases the collar and fluid port into an advanced position;
[0029] FIGS. 8A and 8B are schematic cross-sectional views of a syringe system in accordance with one embodiment of the invention with a collar that may be directed over the needle by a side-arm to secure the collar in the advanced position;
[0030] FIGS. 9A and 9B are schematic cross-sectional views of a syringe system in accordance with one embodiment of the invention with a threaded luer lock collar in a retracted position and in an advanced position;
[0031] FIGS. 10A and 10B are schematic cross-sectional views of a syringe system in accordance with one embodiment of the invention with a deformable elliptical collar in a locked and an unlocked position; and
[0032] FIGS. 11A and 11B are schematic cross-sectional views of an alternative embodiment of the syringe system of FIGS. 9A and 9B .
DETAILED DESCRIPTION OF THE INVENTION
[0033] In the following, embodiments of a syringe system in accordance with the invention are further described with reference to a single application. It is, however, to be understood that the present invention can also be used for other types of syringe or needle systems. For example, in one embodiment, the syringe is a hypodermic syringe used with a hypodermic needle to inject liquid or gases into body tissues, or to remove liquid or gases from the body.
[0034] It will, therefore, be understood that the present invention is directed to a syringe for administering different fluids, which overcomes the problems of the prior art. In particular, a syringe system in accordance with the present invention includes a unique collar with a fluid port that may reversibly lock in a position to expose a puncturing needle or advance to shield the needle and provide a connection for needleless attachment to tubing systems. Manufacture of the component parts of the syringe of the present invention does not involve complicated and expensive manufacturing techniques or precise control over the dimensions of the component parts of the device.
[0035] Referring now to the drawings, in particular FIGS. 1A and 1B , a disposable medical syringe system 1 in accordance with the invention includes a syringe barrel 10 , in the form of a hollow cylinder defining an interior space 40 . The system 1 further includes a plunger 20 inserted into a proximal end 11 of the syringe barrel 10 . The plunger 20 can be advanced into the barrel 10 such that a distal rubber portion 22 of the plunger 20 contacts an internal distal end 12 of the barrel 10 . The plunger 20 has a proximal handle 21 that is used by an operator to slide the plunger 20 through the interior space 40 of the barrel 10 from the proximal end 11 to the distal end 12 of the barrel 10 . The plunger 20 includes one or more sealing surfaces 23 that provide a water tight seal between the distal rubber portion 22 of the plunger 20 and the internal wall of the barrel 10 .
[0036] The barrel 10 includes a generally centrally located opening 13 formed in the distal end 12 of the barrel 10 through which fluid or medication may be pushed or pulled by actuating the plunger 20 and creating forces (e.g., pressure and vacuum) within the interior space 40 , due to the watertight seal of the plunger 20 within the barrel 10 . A hollow needle 30 is coupled to the distal endpoint 14 of the barrel 10 and is in fluid communication with the opening 13 and the interior space 40 . The needle 30 has a proximal end 31 coupled to the distal endpoint 14 of the barrel 10 and a tapered distal end 32 . The tapered distal end 32 of the needle 30 has two side ports 33 that allow fluid transfer and are disposed on the tapered distal end 32 of the needle 30 .
[0037] The volume of the interior space 40 is variable and defined as the space within the barrel 10 and distal to the rubber portion 22 of the plunger 20 . The volume of the space 40 can be varied by movement of the plunger 20 , for example, moving the plunger proximally toward the proximal end 11 enlarges the volume. Movement of the plunger 20 toward the distal end 12 via operator action at the handle 21 causes medication or fluid to be moved by the distal end 22 of the plunger 20 toward the distal needle tip 32 . For example, the fluid is driven through opening 13 and an internal channel 34 of the needle 30 out the needle's distal side ports 33 .
[0038] Referring to FIGS. 1-3 , the syringe system 1 includes at its distal end a collar 60 and a fluid port 50 disposed in the distal end of the collar 60 . In one embodiment, the fluid port 50 is a luer lock type fitting. The collar 60 is coupled to the syringe barrel 10 . In one embodiment, the luer lock 50 includes a longer internal cylinder 51 and a shorter wider surrounding cylinder 52 . The cylinders 51 , 52 extend from a distal end 53 of the collar 60 , with the internal cylinder 51 extending beyond the surrounding cylinder 52 to a distal point 54 . The internal cylinder 51 has an inner diameter (ID 1 ) and an outer diameter (OD 1 ). The surrounding cylinder 52 extends to a distal end 56 and has an inner diameter (ID 2 ) and an outer diameter (OD 2 ). The second inner diameter (ID 2 ) of fluid port 50 includes an internal thread 57 molded therein. In one embodiment, the disposable medical syringe system 1 interfaces with a needleless tubing system via the circumferential thread 57 .
[0039] The collar 60 surrounds and is coupled to at least a portion of barrel 10 near its distal end 14 . The collar 60 may slide back and forth along a portion of the barrel 10 such that when it is in the fully extended position (see FIG. 2 ), the distal end 32 of the needle 30 is covered by the distal end 54 of the fluid port 50 . Alternatively or additionally, the collar 60 may be retracted over the barrel 10 as shown in FIG. 1A , resulting in full exposure of the needle 30 .
[0040] Referring to FIG. 1B , two slotted rails 15 are longitudinally disposed on an exterior surface of the barrel 10 ; however, more rails could be provided. In the embodiment shown, the two rails 15 are equally spaced about the circumference of the barrel 10 . Referring to FIGS. 2 and 4A , the collar 60 includes two protuberances or fingers 62 extending from an interior surface (ID 3 ) of the collar 60 . The protuberances 62 engage the slots 75 ( FIG. 4B ) in the rails 15 , thereby controlling the sliding motion of the collar 60 relative to the barrel 10 between the first, retracted position ( FIG. 1A ) and the second, extended position ( FIG. 2 ). The barrel 10 may include a transversely extending side rail 16 that extends along at least a portion of the circumference of the barrel 10 . The side rail 16 extends from a distal end of the slotted rail 15 and also is slotted for accommodating the protuberance 62 . When the collar 60 is advanced to the extended position, the collar 60 can be rotated such that the protuberances 62 slide within the transverse side rails 16 . By rotating the collar 60 , it can be locked in place to prevent it from sliding back into its retracted position. In the embodiment shown in FIG. 4B , a locking mechanism 17 is disposed in the side rail 16 to prevent the protuberances 62 on the collar 60 from inadvertently rotating out of the side rails 16 . In one embodiment, the locking mechanism is a ramp or inclined block that permanently locks the collar 60 in its extended position. Alternatively, the locking mechanism can be thinned area of the slotted side rail 16 that provides for frictional resistance to the movement of the protuberance 62 . As shown in FIG. 4B , the rail 15 includes a locking mechanism 19 in the form of a bump or thinned area of the rail which provides enough frictional resistance to prevent inadvertent sliding of the collar 60 from the retracted position.
[0041] In one embodiment, again referring to FIG. 4B , the collar may be reversibly locked in the retracted or extended position when the sliding collar thread pushes through an inclined angle 19 , 17 on the barrel located at the proximal and/or distal portion of the slotted rails 15 , 16 .
[0042] Referring to FIGS. 1A and 4A , the collar 60 includes a sealing component 61 . The sealing component 61 can be a rubber o-ring disposed in an annular groove 63 formed in the inside diameter (ID 1 ) of the fluid port. The sealing component 61 maintains a constant watertight seal between the internal diameter (ID 1 ) of the fluid port 50 and the outer diameter (OD 10 ) of the needle 30 through any movement of the collar 60 either proximally to expose the distal end 32 of needle 30 or distally to cover the distal end 32 of the needle 30 (see FIG. 3 ). This results in the prevention of any fluid leakage between the needle 30 and the collar 60 . The system 1 may be attached to a needleless tubing system by the fluid port 50 and medication or other fluid may be injected from the interior space 40 through the needle 30 and out of the fluid port 50 and into the needleless tubing system. In one embodiment, the collar 60 includes an internal channel 79 passing through the distal end of the collar 60 and in which the groove 63 and O-ring 61 are disposed.
[0043] FIGS. 5A and 5B are perspective views of one embodiment of the invention from a user's vantage point. In FIG. 5A , the collar is in the retracted position. In FIG. 5B , the collar 60 is in the extended position. As shown, the collar 60 can include structure 77 , such as knurling or protuberances that aid in the movement of the collar 60 .
[0044] Additional embodiments include the use of a spring 70 ( FIG. 6 ) that favors the uncoiled position 72 (biasing the collar into the advanced position as shown in FIG. 7B ) over the coiled position 71 (i.e., the retracted position shown in FIG. 7A ). The spring 70 can be secured against the internal surface of the distal end 53 of the collar 60 and the external surface of the distal end 12 of the barrel 10 . These surfaces can also include grooves for holding the spring 70 in place.
[0045] Another embodiment allows for a side action luer lock collar attachment as shown in FIGS. 8A and 8B . The side arm 80 is extended in position 81 and the collar 60 is held out to the side such that needle 30 can be used to draw up fluid. In FIG. 8B , the collar 60 is slid over the needle 30 and the side arm 80 is moved into a shortened position 82 , such that the collar 60 covers the needle 30 and the luer lock can engage needleless tubing systems. The arm 80 can be a linkage or other mechanical assembly that can move the collar 60 between the two positions and may include structure for securing the collar 60 in at least one of the two positions, for example the advanced position on the syringe barrel 10 .
[0046] In one embodiment ( FIGS. 9A and 9B ), the rails are replaced by a thread 90 running around the barrel and the collar has a protuberance 91 which may be locked in a retracted position ( FIG. 9A ) or the advanced position ( FIG. 9B ) by rotation of the collar around the barrel. The collar 60 may be locked in place by frictional forces between the thread 90 and protuberance 91 .
[0047] In another embodiment ( FIGS. 10A and 10B ), the collar 60 has an elliptical or circular circumference in the retracted position (elliptical and locked in FIG. 10A ) which is then deformed to the other shape (elliptical or circular) to move the collar into the advanced position (circular and slideable in FIG. 10B ) to aid in reversibly holding the collar in the retracted or advanced position by the frictional engagement of the collar with the barrel.
[0048] In yet another embodiment ( FIGS. 11A and 11B ), which is a variation of FIGS. 9A and 9B , there is an additional external cylinder 110 that has an internal thread 111 , such that rotation of the cylinder 110 causes advancement of the collar 60 from the retracted position ( FIG. 11A ) to the advanced position ( FIG. 11B ) by the interface of the thread 111 with an external collar thread 112 and by the internal collar thread 90 interfacing with the protuberance 91 .
[0049] The syringe system 1 may draw up medication from a medication bottle in a standard fashion with the collar 60 reversibly locked in its retracted position ( FIG. 1A ) and the operator pulling back on the proximal handle 21 of the plunger 20 . By this action, medication is drawn into the enlarging interior space 40 . Once this is complete, the collar 60 may be reversibly locked into its extended position as seen in FIG. 2 , simultaneously covering the distal end 32 of the needle 30 , and maintaining a seal between the sealing component 61 and the needle 30 . After converting the system 1 from needled to needleless, the syringe system 1 may be easily attached to the needleless tubing system via, for example, the threads 57 on the fluid port 50 . The plunger 20 may be advanced to move the medication distally through the sealed system and out through the needle openings 33 into the needleless tubing system.
[0050] The size and shape of the syringe and associated components will vary to suit a particular application and patient (e.g., adult or pediatric). The specific dimensions, capacities, configurations will be selected to suit a particular application. For example, the syringe can have a volumetric capacity of about 0.05 cc to about 100.0 cc, the needle can be from about 33 gauge to about 10 gauge, and the needleless interface can be a luer type fitting.
[0051] Generally, the components of the syringe system can be manufactured by injection molding or by modifying an extruded tube. For example, extrusion can be used to provide a uniform polymeric tube, to which other components are attached. Insert molding can be used to provide the desired geometry of the components and openings in a component can then be created in the desired locations as a subsequent mechanical operation. Additional manufacturing techniques include blow molding, compression molding, transfer molding, and any other molding techniques. For example, single-shot or multi-shot injection molding. The various components of the syringe system can be assembled by snap fitting, bonding, and/or tongue and groove connection.
[0052] The syringe and related components can be manufactured from glass or plastic and may be made of a biocompatible material, such as, for example, polyurethane, silicones, polyethylenes, nylons, polyesters and polyester elastomers, either with or without reinforcement. Stainless steel and titanium can also be used, for example, for the needle. In addition, the needle can be formed from a polymeric material or a combination of metal and polymeric materials, for example, the needle can be stainless steel with a polymer over-molded on to the needle. The needle can have a sharp or blunt tip. Also, the polymeric materials may be used in combination with other materials, for example, natural or synthetic rubber. Other suitable materials will be apparent to those skilled in the art. In one embodiment, the barrel of the syringe is made of plastic, has graduated marks indicating the volume of fluid in the syringe, and is substantially transparent. The syringe plunger or piston may be made of rubber, which provides a good seal between the piston and the barrel.
[0053] Various examples of syringe systems and their manufacturing, material, and arrangement details can be found in U.S. Pat. Nos. 7,182,734; 5,817,065; 5,681,295; and 5,273,543, the entire disclosures of which are incorporated herein by reference in their entireties.
[0054] Having described certain embodiments of the invention, it will be apparent to those of ordinary skill in the art that other embodiments incorporating the concepts disclosed herein may be used without departing from the spirit and scope of the invention. The described embodiments are to be considered in all respects as only illustrative and not restrictive. | The present invention relates to a syringe system that allows rapid conversion between a needle/syringe system and a needleless/syringe system and in doing so allows an operator to move seamlessly between both systems, while minimizing needle stick risk. In this way, an operator may rapidly access medication bottles requiring a needle puncture and access needleless tubing systems requiring a needleless interface. | 0 |
BACKGROUND
Current heads-up display (HUD) systems require complex display projection/combiner hardware. A typical HUD contains a projector unit, a combiner, and a display computer. The projection unit in a typical HUD is an optical collimator with a convex lens or concave mirror and a display element producing an image where the light is collimated. The combiner is typically an angled flat piece of glass (a beam splitter), located directly in front of the viewer, that redirects the projected image from projector in such a way as to see the field of view and the projected image at the same time. The combiner may have a special coating that reflects the monochromatic light projected onto it from the projector unit while allowing all other wavelengths of light to pass through. In some optical layouts, combiners may also have a curved surface to refocus the image from the projector.
Existing HUD systems are not suitable for installation into many airplanes because of weight and complexity. Consequently, it would be advantageous if an apparatus existed that is suitable for providing HUD functionality in vehicles.
SUMMARY
Accordingly, embodiments of the inventive concepts disclosed herein are directed to a transparent film display system that may be implemented to provide HUD functionality in some embodiments.
In one aspect, the inventive concepts disclosed herein are directed to a transparent flexible display film applied to a surface. The transparent flexible display film is applied to a vehicle window much like tinting membranes. Informational indicators are rendered on the transparent flexible display film. In some embodiments, the transparent flexible display film may be made an integral part of the glass similar to laminated safety glass. A computer control port connects a computer to the transparent flexible display film.
In some applications, the computer may present to the occupants a synthesized view of the external environment around the vehicle to protect the occupants from external sources of danger such as IED's, and small arms fire.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and should not restrict the scope of the claims. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the inventive concepts disclosed herein and together with the general description, serve to explain the principles.
BRIEF DESCRIPTION OF THE DRAWINGS
The numerous advantages of the embodiments of the inventive concepts disclosed herein may be better understood by those skilled in the art by reference to the accompanying figures in which:
FIG. 1 shows an embodiment of a transparent display system according to the inventive concepts disclosed herein;
FIG. 2 shows an environmental view of a transparent display system according to one embodiment of the inventive concepts disclosed herein;
FIG. 3 shows an environmental view of one embodiment of a transparent display system according to the inventive concepts disclosed herein;
FIG. 4 shows an environmental view of one embodiment of a transparent display system according to the inventive concepts disclosed herein incorporated into an automobile;
FIG. 5 shows an environmental view of one embodiment of a transparent display system according to the inventive concepts disclosed herein incorporated into an automobile;
FIG. 6 shows an environmental view of one embodiment of a transparent display system according to the inventive concepts disclosed herein incorporated into an automobile;
FIG. 7A shows an environmental view of one embodiment of a transparent display system according to the inventive concepts disclosed herein incorporated into an aircraft;
FIG. 7B shows an environmental view of one embodiment of a transparent display system according to the inventive concepts disclosed herein incorporated into an aircraft;
FIG. 7C shows an environmental view of one embodiment of a transparent display system according to the inventive concepts disclosed herein incorporated into an aircraft;
DETAILED DESCRIPTION
Reference will now be made in detail to the subject matter disclosed, which is illustrated in the accompanying drawings. The scope of the inventive concepts disclosed herein is limited only by the claims; numerous alternatives, modifications and equivalents are encompassed. For the purpose of clarity, technical material that is known in the technical fields related to the embodiments has not been described in detail to avoid unnecessarily obscuring the description.
Referring to FIG. 1 , an embodiment of a transparent display system 100 according to the inventive concepts disclosed herein is shown. The computer system 100 includes a processor 102 and memory 104 connected to the processor 102 for storing computer executable code. The transparent display system 100 also includes a transparent flexible display film 106 connected to the processor 102 . In some embodiments, a touch-sensitive film 108 connected to the processor 102 may overlay the transparent flexible display film 106 . In some embodiments, a camera 110 may be connected to the processor 102 for head or eye tracking. Further, in some cases a head tracking system other than the camera 110 may be implemented, such as an inertial measuring unit, an optical tracker, a magnetic tracker, or combinations thereof.
The transparent flexible display film 106 may comprise transparent conductors based on silver nanowires and organic light emitting diodes (OLED), active matrix organic light emitting diodes (AMOLED) or other appropriate technology for creating a transparent flexible display film 106 . Silver nanowires have significantly higher optical and electrical conductivity than other currently used materials such as indium tin oxide (ITO) and other transparent conductors. In one embodiment, the transparent flexible display film 106 may be applied to a glass windshield; alternatively, the transparent flexible display film 106 may be incorporated into the Laminated glass windshield of an aircraft or other vehicle to create safety glass with embedded display capability. The direct use of the windshield as compared to a combiner allows the processor 102 to display HUD or other appropriate information directly in the operator's view. A person skilled in the art may appreciate that “transparent,” as used in the present disclosure refers to light transmission sufficient to allow a user to resolve external details through a window including transparent flexible display film 106 .
In some embodiments, the transparent flexible display film 106 may be applied to non-transparent surfaces in a vehicle.
The transparent flexible display film 106 may be produced via 3 D printing or specialized ink-jet printing to print circuitry onto a transparent film for quickly creating circuitry. Further, some materials, for example polyimide, PEEK, or transparent conductive polyester, allow circuit boards and OLED/AMOLED displays to be applied to curved surfaces.
The transparent display system 100 may also include an antenna 112 connected to the processor 102 . The processor 102 receives data corresponding to an external event, such as a weather related phenomena, and renders an image of the external event on the transparent flexible display film 106 . The processor 102 may select a rendering location based on a known location and orientation of the transparent flexible display film 106 and a location of the external event based on the received data.
Referring to FIG. 2 , an environmental view of an embodiment of a transparent display system 200 according to the inventive concepts disclosed herein is shown is shown. A transparent flexible display film 202 is connected to a computer via a data cable 204 , or some other wireless connection, and applied to a transparent surface such as a cockpit window 201 .
In some embodiments, the transparent flexible display film 202 may comprise a touch sensitive film 208 , also connected to the computer via the data cable 204 .
While certain specific embodiments described herein refer to a transparent flexible display film 202 applied or incorporated into a windshield, some embodiments may be incorporated into other windows and surfaces in a vehicle. Furthermore, transparent flexible display films 202 covering various windows and surfaces in a vehicle may be configured to allow continuous images across more than one transparent flexible display film 202 .
Referring to FIG. 3 , an environmental view of one embodiment of a transparent display system 300 according to the inventive concepts disclosed herein is shown incorporated into an aircraft cockpit. One or more exterior windows 301 of the aircraft include a transparent flexible display film 302 applied to the interior surface of the exterior window 301 , or incorporated as a layer in a laminated glass exterior window 301 . The transparent flexible display film 302 is connected to a computer in the aircraft via a data cable 304 or a wireless data communication mechanism. In at least one embodiment, the computer system may be incorporated into an avionics system that also provides data to standard glass cockpit display 306 systems.
Information displayed via the transparent flexible display film 302 may be HUD type cues or ghost information from an active panel in the glass cockpit display 306 . In some embodiments, the transparent display system 300 may receive critical notifications from some avionics sub-system and replicate relevant avionics data on a transparent flexible display film 302 so that the operator is made aware of all relevant data to deal with the critical notification without looking away from the cockpit exterior window 301 . In some embodiments, the transparent display system 300 may display a critical notification warning on the transparent flexible display film 302 , within the likely line-of-sight of the operator. Operators are thereby less likely to ignore or miss critical notifications or information.
In some embodiments, the transparent display system 300 may receive data from an avionics system indicating the position and orientation of the aircraft, and produce graphical representations of important phenomena, approximately overlaid against the actual phenomena from the pilot's perspective based on the likely position of the pilots head. For example, the position or direction of otherwise invisible weather phenomena such as clear air turbulence may be indicated. Likewise, runway edges may be accentuated or “Lanes in the sky” as described in by FAA NextGen may be outlined against the actual sky.
Referring to FIGS. 4 and 5 , an environmental view of an exemplary embodiment of a transparent display system 400 according to the inventive concepts disclosed herein is shown incorporated into an automobile. A transparent flexible display film is applied to an automobile windshield 401 or incorporated as a layer in the laminated glass comprising the windshield 401 . Information displays 402 , 404 , 406 , 408 traditionally relegated to an automobile dashboard may be displayed on the transparent flexible display film.
Additionally, because the information displays 402 , 404 , 406 , 408 are instantiated in a display film, the information displays 402 , 404 , 406 , 408 may be repositioned. For example, a first information display 402 may be moved from a first position ( 402 ) to a first information display second position 502 . Likewise, a second information display 404 may be moved to a second information display second position 504 , a third information display 406 may be moved to a third information display second position 506 , and a fourth information display 408 may be moved to a fourth information display second position 508 .
In some embodiments, the transparent display system 400 connected to the transparent flexible display film may define one or more fixed second positions 502 , 504 , 506 , 508 designed to keep the information displays information displays 402 , 404 , 406 , 408 within the line of sight of the driver. In another embodiment, the second positions 502 , 504 , 506 , 508 may be adjustable by the user, for example via a touch sensitive film.
Referring to FIG. 6 , an environmental view of an exemplary embodiment of a transparent flexible display system 600 according to the inventive concepts disclosed herein is show incorporated into an automobile. A transparent flexible display film is applied to an automobile dashboard 601 . Information displays 602 , 604 , 606 , 608 traditionally relegated to an automobile dashboard 601 may be displayed on the transparent flexible display film.
Referring to FIGS. 7A-7C , environmental views of an embodiment of a transparent display system 700 according to the inventive concepts disclosed herein are shown incorporated into an aircraft. An aircraft includes windshields 708 and exterior windows 701 including transparent flexible display films. A computer generating images on the transparent flexible display films, and connected to avionics systems on board the aircraft, may identify visual events, such as a proximate aircraft 704 , that should be highlighted or data that may be represented visually. In one embodiment, the computer knows or is calibrated to know the location of the pilot's head 706 . The computer generates visual indicia 702 at a location on the transparent flexible display film corresponding to the intersection of a line defined by the pilot's head 706 and an indicated visual event, such as the proximate aircraft 704 , and the exterior window 701 or windshield 708 as appropriate. The visual indicia 702 indicate where the pilot should look to visually identify a critical event. The location of the visual indicia 702 on the transparent flexible display film may be updated periodically based on orientation of the aircraft and the changing location of the proximate aircraft 704 .
In addition, the computer may identify the pilot's actual line-of-sight 712 , for example with an eye-tracking camera, and project a motion line 710 on the transparent flexible film indicating where the pilot should look to see the visual indicia 702 . Further, the computer may render a visual representation of “lanes in the sky” 708 based on known, defined locations of such lanes 708 and the position and orientation of the aircraft and the known location of the pilot's head 706 .
Some embodiments of the inventive concepts disclosed herein obviate the need for heavy, specialized glass and projection systems in existing HUD systems by displaying information directly on the windshield of an aircraft or other vehicle. This type of thin film display allows installation into a wider range of vehicles without the added weight and cost of a HUD projection and mounting bracket with specialized glass. Further, whereas some combiner glass coatings where operable in a wavelength range corresponding to a single color, embodiments of the present disclosure may utilize a full spectrum of colors. Some embodiments render a synthesized view of the external environment around the vehicle, including visual representations of information received from an on-board data sensor or from an external source through an antenna.
It is believed that the inventive concepts disclosed herein and many of their attendant advantages will be understood by the foregoing description of embodiments of the inventive concepts, and it will be apparent that various changes may be made in the form, construction, and arrangement of the components thereof without departing from the broad scope of the inventive concepts disclosed herein or without sacrificing all of their material advantages. The form herein before described being merely an explanatory embodiment thereof, it is the intention of the following claims to encompass and include such changes. | A transparent flexible display film is applied to a vehicle windshield, either as a film applied to the surface of the windshield or as a layer in the laminated glass comprising the windshield. A connected computer renders a synthesized view of the external environment around the vehicle, including visual representations of information received from an on-board data sensor or from an external source. No special glasses or helmets are required for the operators and if the system fails, the display film is transparent and will not impede the operators view. | 1 |
This is a continuation of International PCT Application No. JP99/03174 filed Jun. 14, 1999, which was not published in English.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a magnetic recording medium applied to a hard disc drive and a method of manufacturing the same medium.
In recent years, reduction in size and enlargement of capacity are essential requirements for a hard disc drive which plays the concentrated role of an information storage apparatus. These requirements can be realized by enhancing the recording density of a magnetic disc medium. In order to increase the recording density, it is requested to realize reduction in thickness of a magnetic film, improvement in resolution, high coercive force and low noise.
2. Description of the Related Art
As the recording density of a magnetic disc medium becomes high, an area of one bit on the medium is reduced. In such background, it is required, for acquisition of an output, to make the magnetic layer thinner corresponding to a reduction in the size of a bit. Thereby, a semi-circular magnetic field can be assured and thereby leakage magnetic field generated from the magnetization area of one bit can be obtained. Moreover, since it is also required to narrow the bit interval, improvement in the magnetic domain structure in the magnetization transition area, scale-down of crystal grain corresponding to reduction in thickness and noise reduction by reduction in magnetic mutual operations among the particles or the like are necessary.
As a magnetic layer of a medium, a CoCr group alloy polycrystalline film formed of three or more elements has been used as a material of the magnetic layer. In the existing medium, Cr included in the magnetic grains of a magnetic layer is segregated into the crystal grain boundary and this grain boundary is non-magnetized to reduce mutual operation among the particles. In the related art, in order to promote this segregation, adding coefficient of Cr to alloy is increased, Ta or the like is added and a substrate is also heated during the film forming process.
As explained above, while a means for segregating Cr included in the magnetic grains into the crystal grain boundary and non-magnetizing this grain boundary region is introduced, it is essential to use the CoCr group alloy magnetic material as a material of the magnetic layer. However, when reduction in thickness of magnetic layer and scale-down of crystal grains are promoted, a volume of individual magnetic grains is reduced, thermal disturbance is finally generated to result in the super-normal magnetization and the magnetic recording condition can no longer be maintained. In order to reduce the volume of individual magnetic grains as much as possible to a small amount, it is best to use a magnetic material having a higher anisotropic constant Ku. In the Co-based magnetic material, a value of Ku is lowered by as much as about one digit by adding Cr to the discrete element of Co. Therefore, use of the CoCr group alloy will make it very difficult to maintain the value of Ku. Moreover, the discrete element of Co will bring about a problem that corrosion proof characteristic is deteriorated.
An object of the present invention is to provide a magnetic recording medium having higher recording density. Moreover, another object of the present invention is to realize a reduction in thickness of a magnetic film of a magnetic recording medium. Moreover, the other object of the present invention is to reduce noise of the magnetic recording medium itself.
In the present invention, unlike the CoCr group alloy used as a material of a magnetic layer, a Co-based alloy, where a non-magnetic element different from Cr is added to the Co discrete element, is used as a material of the magnetic layer. According to the present invention, reduction of the value of Ku due to the formation of alloy is controlled, and thereby a problem in reduction of thickness of magnetic layer in a magnetic recording medium can be solved.
However, when a Co-based alloy not including Cr is used as a material of the magnetic layer, Cr included in the magnetic grains is segregated into the crystal grain boundary and the grain boundary region can no longer be non-magnetized. Therefore, in the present invention, a Cr-based non-magnetic material is used as an underlayer. According to the present invention, the grain boundary region can be non-magnetized by segregating Cr to the crystal grain boundary from the underlayer. In practice, diffusion of Cr into the crystal grain boundary of the magnetic layer from the underlayer is induced with post-annealing. As a result, the magnetic layer has a structure in which Cr exists only at the area near the crystal grain boundary, and thereby non-magnetization of the grain boundary region of the magnetic layer can be realized. Since the grain boundary region of the magnetic layer is non-magnetized, magnetic mutual operation among the grains can be reduced, and noise of magnetic recording medium can also be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a disc medium of the present invention.
FIG. 2 is a diagram showing a crystal structure of a magnetic layer after the post-annealing.
FIG. 3 is a graph showing the relationship between the post-annealing temperature and magnetization characteristic.
FIG. 4 is a diagram showing the growth process of magnetic grains.
FIGS. 5( a ) and 5 ( b ) are graphs showing the relationships between concentrations of additives of Co-based alloy and Ku values.
FIG. 6 is a graph showing the relationship between Cr concentration in CoCrPt and Ku value.
FIG. 7 is a graph showing the relationship between W concentration in CoW and Ku value.
FIG. 8 is a plan view of the magnetic disc drive as an embodiment of the present invention.
FIG. 9 is a cross-sectional view of the magnetic disc drive of FIG. 8 as an embodiment of the present invention.
FIG. 10 is a diagram showing a structure of a sputtering apparatus.
FIG. 11 is a flowchart of the process to form a medium in an embodiment of the present invention.
FIG. 12 is a cross-sectional view of an existing medium.
FIG. 13 is a flowchart of the process to form an existing medium.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a cross-sectional view of a magnetic recording medium of the present invention. In the magnetic recording medium 1 of the present invention, an underlayer 3 , a magnetic layer 4 , and a protection layer 5 are sequentially formed on a substrate 2 . Each film forming the magnetic recording medium 1 will be explained below.
The substrate 2 is formed of a non-magnetic material of a disc shape. A material forming the substrate 2 includes an NiP plated aluminum (including aluminum alloy) disc, a glass (including reinforced glass) disc, a silicon disc having a surface oxide film, an SiC disc, a carbon disc, a plastic disc, a ceramic disc or the like. Moreover, the substrate 2 is not always required to have completed the texture process. The size of substrate 2 is determined depending on the kind of desired medium and magnetic disc drive as the application object or the like. In general, the external diameter is in the range of 65 mm to 95 mm, the internal diameter is in the range of 20 mm to 25 mm and the thickness is in the range of 0.635 mm to 0.8 mm.
The underlayer 3 is formed of a non-magnetic metal material mainly composed of chromium. As a practical matter, a metal material mainly composed of only chromium or chromium alloy such as CrW, CrV, CrTI, CrMo or the like may be used. The underlayer 3 is formed, for example, with a sputtering method such as magnetron sputtering or the like. As adequate film forming conditions, for example, the substrate temperature is 30° C., the Ar gas pressure is 3 to 5 m Torr, and the input power is 100 to 800 W. Moreover, it is also possible to introduce, in place of the sputtering method, other film forming methods, for example, vacuum evaporation or ion beam sputtering or the like. Film thickness of the underlayer 3 is determined within a wider range depending on various factors but the thickness is preferentially set within the range of 2 nm to 14 nm to improve S/N ratio. If the underlayer film thickness is 2 nm or less, a problem that sufficient magnetic characteristic cannot be obtained is generated, and if thickness becomes 14 nm or more, on the contrary, noise tends to be increased.
The magnetic layer 4 is formed of a Co-based alloy mainly composed of cobalt and an alloy where a non-magnetic material other than Cr is added to Co, for example, CoPt alloy and CoW alloy or the like are formed. It is preferable for the magnetic layer 4 that it is formed with a sputtering method such as magnetron sputtering or the like and for example, the substrate temperature is set to 30° C., as the adequate film forming conditions, Ar gas pressure is set to 3 to 5 m Torr and input power is set to 100 to 800 W. Moreover, other film forming methods, such as vacuum evaporation and ion beam sputtering or the like may be used in place of the sputtering method.
The protection layer 5 is composed of a discrete carbon or a composite including carbon. For example, WC, SiC, B 4 C, carbon including hydrogen and a diamond like carbon (DLC) that is noted in such a point as having higher hardness may be listed. It is preferable that the protection layer 6 be formed with a sputtering method such as magnetron sputtering or the like. As the preferable film forming conditions, for example, the substrate temperature is set to 30° C., Ar gas pressure is set to 3 to 5 m Torr and input power is set to 300 to 500 W. Moreover, other film forming methods such as vacuum evaporation and ion beam sputtering or the like can be substituted for the sputtering method. The thickness of the protection layer 6 is determined in a wider range depending on various factors, and the preferable thickness is in the range of 4 nm to 8 nm.
Here, it is also allowed that a lubricant film is formed on the protection layer. The lubricant film is usually composed of a fluororocarbon resin based material in the thickness of 1 mm to 2 nm.
The present invention diffuses Cr included in the underlayer 3 into the crystal grain boundary of magnetic layer 4 with the post-annealing.
FIG. 2 shows a crystal structure in the magnetic layer 4 of the magnetic recording medium 1 after the post-annealing.
In FIG. 2 , a dotted line indicates the grain boundary, the region surrounded by a solid line is the region composed of a Co-based alloy (Cr is not included) and the region surrounded by the dotted line and solid line is the region composed of a CoCr based alloy. From FIG. 2 , it is understood that Cr is segregated only to the area near the crystal grain boundary with the post-annealing. Since Cr is diffused into the crystal grain boundary of the magnetic layer 4 , magnetic mutual operation among the crystal grains of magnetic layer 4 is impeded. Thereby, generation of noise in the magnetic layer 4 can be controlled.
However, when the post-annealing is executed after formation of the protection layer 5 mainly composed of carbon as explained above, carbon reaches the surface of the underlayer 3 passing through the crystal grain boundary to form a film to impede diffusion to the grain boundary of magnetic layer 4 of Cr of the underlayer 3 . Therefore, it is preferable to execute the post- annealing after the magnetic layer 4 is formed and before the protection layer 5 is formed. Moreover, if the magnetic layer 4 is exposed before the protection layer 5 is formed, when the substrate 2 is exposed to the atmospheric condition under this condition, an oxide film is formed at the surface. Since this oxide film is condensed during the post-annealing to provide roughness of the surface, it is preferable that the post-annealing is conducted while the vacuum condition is maintained after lamination of the magnetic film 4 .
FIG. 3 shows the temperature dependence characteristics of a coercive force Hc in the post-annealed medium (underlayer is Cr and magnetic layer is CoPt) and the standardized coercive force Hc/Hk.
As shown in FIG. 3 , diffusion of Cr to the crystal grain boundary of the magnetic layer from the underlayer is induced at temperatures higher than 350° C. Moreover, it is also understood that the Hc/Hk value can be increased, while the anisotropic magnetic field Hk does not change, by setting the post-annealing temperature to 350° C. or higher. These results indicate that the mutual operations among grains are reduced and diffusion of Cr to the crystal grain boundary of magnetic layer is accelerated. In the post-annealing temperature region exceeding 30° C., the Hc/Hk value becomes higher as the post-annealing temperature rises. Therefore, it can also be proved that segregation of Cr can be controlled depending on the post-annealing temperature.
FIG. 4 shows a growth process of magnetic grains of the magnetic layer. As the magnetic layer, CoCrPt is used, and as the underlayer, Cr is used.
For acceleration of segregation of Cr due to the post-annealing, it is effective to introduce a medium forming technique to laminate the underlayer and the magnetic layer with the sputtering method in place of the heat treatment of the substrate. In this technique, as shown in FIG. 4 , since the forming condition in which one magnetic grain grows on one crystal grain of the underlayer is realized, the plain size of the magnetic grains can be controlled with the plain size of the crystal grains of the underlayer.
FIGS. 5( a ) and 5 ( b ) show graphs indicating the relationship between the concentration of additives and anisotropic constant Ku in the Co based magnetic material. FIG. 5( a ) is a graph where Pt is added as the additive, while FIG. 5( b ) is a graph where Cr is added as the additive. From FIG. 5( a ) and 5 ( b ), it can be understood that when the concentration of the additive becomes higher, Ku becomes lower than 4e+6(erg/cc), which is the Ku value of discrete element of Co. However, a lowering degree in the case where Cr is added as the additive becomes larger than that in the case where Pt is added, and a higher reduction degree is indicated in the region where Cr concentration is 5 at % or less. Therefore, if the CoCr based alloy is used for the magnetic layer, it is preferable to set the Cr concentration to 5 at % or less, if possible, to 3 at % or less where the Ku value which is higher than the half of Ku value of discrete element of Co can be obtained.
FIG. 6 is a graph indicating the relationship between the Cr to Pt ratio in CoCrPt (concentration of Co has the constant value of 78%) and the Ku value. From FIG. 6 , it can be understood that the Ku value is lowered when a rate of Pt is decreased and a rate of Cr is increased. When the rate of Pt is 0 and additional coefficient of Cr is 22%, which is the practical adding coefficient, Ku becomes 4e+5(erg/cc) which is about 1/10 of the Ku value of discrete element of Co.
FIG. 7 is a graph showing the relationship between the adding coefficient of W in CoW and the Ku value. From FIG. 7 , it can be understood that while the adding coefficient of W is in the range of 0 to 16 at % and when the adding coefficient of W is increasing, the value of Ku becomes larger, but when the adding coefficient of W exceeds 16 at %, the Ku value rapidly decreases. However, in CoCr, a Ku value higher than that in addition of Cr in the same concentration can be obtained. From FIG. 7 , it can be seen that the concentration of W should preferably be 16 at % or less when CoW is used for the magnetic layer.
As explained above, from the graphs of FIG. 5 to FIG. 7 , it can be understood that the addition of Cr remarkably reduces the Ku value, and that reduction of the Ku value can be reduced or increased by adding Pt and W in place of Cr. When the discrete element of Co is used as the magnetic layer, a higher Ku value can be obtained as shown in FIGS. 5( a ) and 5 ( b ), but simultaneously corrosion proof characteristic is deteriorated. Accordingly, it is required to enhance passivation but it is inferior for practical use. Moreover, when the magnetic material not including Cr is used, a problem is generated in which the grain boundary region cannot be non-magnetized. But, this problem can be solved by inducing diffusion of Cr into the crystal grain boundary of the magnetic layer from the underlayer with post- annealing, as explained above.
On the other hand, the present invention is also applied to the magnetic disc drive including the magnetic recording medium explained above, and an example of the magnetic disc drive is shown in FIG. 8 and FIG. 9 . FIG. 8 is a plan view of the magnetic disc drive of the present invention under the condition that a cover is removed, while FIG. 9 is a cross-sectional view along the line A-A of FIG. 8 .
In these figures, numeral 50 designates a magnetic disc driven with a spindle motor 52 provided on a base plate 51 . In this embodiment, three magnetic discs are provided.
Numeral 53 is an actuator supported to rotate on the base plate 51 . One end of the actuator 53 is provided with a plurality of head arms 54 extending in the direction parallel to the recording surface of the magnetic disc 50 . One end of the head arm is provided with a spring arm. A slider 40 is mounted to the flexure part of spring arm 55 via-an insulation film (not shown). The other end of actuator 53 is provided with a coil 57 .
On the base plate 51 , a magnetic circuit 58 formed of a permanent magnet and a yoke is provided and the coil 57 explained above is allocated within a magnetic gap of the magnetic circuit 58 . A voice coil motor (VCM) is structured with the magnetic circuit 58 and coil 57 . Moreover, the upper part of base plate 51 is covered with a cover 59 .
Operations of the magnetic disc drive explained above will now be explained. While the magnetic disc 50 does not rotate, the slider 40 is in the stationary condition in contact with the saving zone of the magnetic disc 50 . Next, when the magnetic disc drive 50 is rotated by the spindle motor 52 , the slider 40 is levitated from the disc surface, keeping a small gap with the air flow generated with rotation of the magnetic disc 50 . When a current flows into the coil 57 while the slider is levitated, a propulsive force is generated in the coil 57 to rotate the actuator 53 . The slider 40 moves to the position on the predetermined track of the magnetic disc 50 to read or write data from or to the disc.
In the present invention, a DC magnetron sputtering apparatus 10 as shown in FIG. 10 is used to form the predetermined film on the substrate. The sputtering apparatus 20 is provided, as shown in the figure, with a gas supply port 22 for guiding the gas into the sputtering chamber 21 , an exhaust port 23 , a susceptor 24 for supporting a disc substrate, a target 25 and a magnet 26 .
In view of verifying the effect of use of the magnetic layer not including Cr and the effect of non-heating of the substrate in the laminating process, three kinds of media indicated below are manufactured on trial to measure the respective magnetic characteristics.
1. Medium A:
As shown in FIG. 1 , the cross-section of the medium A is formed of an underlayer 3 , a magnetic layer 4 and a protection layer 5 laminated sequentially on a substrate 2 . The manufacturing process of medium A is shown in FIG. 11 . The manufacturing process of medium A will be explained with reference to FIG. 11 . S 1 : An underlayer 3 is laminated on a substrate 2 consisting of a Si disc with an external diameter of 6.5 mm, an internal diameter of 20 mm and a thickness of 0.635 mm on which surface a silicon oxide film is formed in the thickness of 300 nm. The underlayer 3 is composed of a polycrystalline film of Cr. After the chamber of the sputtering apparatus is evacuated to 5e-10 Torr, a film is formed in the thickness of 5 nm on the substrate 2 under the condition that the Ar gas pressure in the sputtering chamber is set to 3 m Torr. S 2 : A magnetic layer 4 is laminated on the underlayer 3 . The magnetic layer 4 is formed of a CoPt alloy polycrystalline film, and this film is formed in the thickness of 14 nm on the underlayer 3 under the conditions that the Ar gas pressure in the sputtering chamber is set to 3 m Torr and the input power is set to 100 W. The magnetic layer 4 of medium A has the composition of cobalt of 88 at % and platinum of 12 at %.
On the occasion of forming a film of magnetic layer 4 , a bias voltage is set to OV in order to avoid the heat processing of the substrate. Moreover, in order to attain high purity of film, a partial pressure of oxidized gas element is reduced to 1e-11 Torr or less by reducing the vacuum base pressure (1e-9 Torr) and purifying the Ar gas.
S 3 : After the magnetic layer 4 is formed, the vacuum condition is held and the post-annealing is performed for 20 seconds at 450° C. to sufficiently induce the diffusion of Cr to the magnetic layer 4 from the underlayer 3 .
S 4 : A protection layer 5 is laminated on the magnetic layer 4 . The protection layer 5 is formed after the post-annealing. This layer 5 is formed in the thickness of 5 nm on the magnetic layer 4 under the conditions that the substrate temperature is 30° C., the Ar gas pressure in the sputtering chamber is set to 3 m Torr and the input power is set to 1000 W.
From the medium A manufactured as explained above, a value of Ku of 3.7 e+6(erg/cc) and a value of Hc/Hk of 0.44 have been obtained. The Ku value obtained here is larger than 8e+5(erg/cc), which is the value of Ku of the medium of which the magnetic layer is composed of Co66Cr22Pt12. Moreover, as the value of Hc/Hk, 0.44 has been obtained by reflecting the width of the non-magnetized region of the grain boundary portion formed with diffusion of Cr into the grain boundary of magnetic layer. From this result, it has been proved that sufficient grain boundary segregation of Cr can be realized even in the medium where Cr is not added to the magnetic layer. Here, it has also been confirmed that Cr exists only in the region within 3 nm from the crystal grain boundary in the magnetic layer 4 .
2. Medium B:
A structure of the layer of medium B is shown in FIG. 12 . Unlike medium A, medium B has a magnetic layer 4 ′ including Cr. The manufacturing process of medium B is shown in FIG. 13 . The manufacturing process of medium B will be explained with reference to FIG. 13 .
S 11 : An underlayer 3 is laminated on a substrate 2 . The shape and material of the substrate 2 are identical to that of medium A. The underlayer 3 is composed of the polycrystalline film of Cr and it is formed in the thickness of 5 nm on the substrate under the conditions that the sputtering chamber is evacuated to 5e-Torr, the Ar gas pressure in the sputtering chamber is set to 3 m Torr and the input power is set to 100 W.
S 12 : The substrate 2 is heated up to 250° C. S 13 : A magnetic layer 4 is formed on the underlayer 3 . The magnetic layer 4 ′ is composed of the CoCr group alloy magnetic material and it is formed on the underlayer 3 in the thickness of 14 nm under the condition that the substrate 2 is heated, the Ar gas pressure in the sputtering chamber is set to 3 m Torr and the input power is set to 100W. The composition of magnetic layer 4 ′ of medium A has the composition of cobalt of 75 at % and chromium of 13 at %. S 14 : A protection layer 5 is also formed on the magnetic layer 4 ′. The protection layer 5 is formed in the thickness of 5 mm on the magnetic layer 4 ′ under the conditions that the substrate temperature is set to 30° C., the Ar gas pressure in the sputtering chamber is set to 3 m Torr and the input power is set to 1 kW.
In medium B manufactured as explained above, since Cr is added to the magnetic layer 4 ′, the Hc/Hk value of 0.3 has been obtained because the grain boundary region can be non-magnetized by segregating Cr included in the magnetic grains into the grain boundary on the occasion of deposition. However, the Ku value obtained has only been 7e+6(erg/cc).
3. Medium C:
The shape of the cross-section of medium C is identical to that of medium A and is shown in FIG. 1 . Moreover, the manufacturing process is as shown in FIG. 11 , which is identical to the process of medium A. The only difference from the manufacturing process of medium A is that the substrate is heated up to 250° C. when the magnetic film 4 is formed with the sputtering method.
From medium C manufactured as explained above, the Ku value of 3.7e+6(erg/cc) has been obtained as in the case of medium A. However, diffusion of Cr into the grain boundary of the magnetic layer does not occur, and the Hc/Hk value has been reduced to 0.1 or less.
From the values of Ku and Hc/Hk of each medium manufactured as explained above, it can be understood that a comparatively larger Ku value can be obtained in media A and C where Cr is not added to the magnetic layer, and moreover a large Hc/Hk value has been obtained in medium A where the substrate is not heated when the magnetic layer is formed. From this result, it has also been confirmed that Cr should not be added to the magnetic layer to obtain a large Ku value, while the sputtering process should be conducted without heating the substrate in order to obtain a large Hc/Hk value.
In the present invention, since the Co based alloy in which Cr is not added is used as a material of the magnetic layer, the Ku value is maintained at higher value. Since the Ku value is high, the volume of crystal grains for starting deterioration of magnetic characteristic due to the thermal disturbance becomes small, and thereby reduction in the thickness of the magnetic film can be accelerated. As a result, an area of one bit can be reduced, and thereby high recording density can be achieved. Moreover, since the Cr-based alloy is used as the material of the underlayer, Cr can be diffused into the grain boundary of the magnetic layer from the underlayer. Since Cr is diffused into the grain boundary, the grain boundary of the magnetic layer can be non-magnetized. As a result, the magnetic mutual operation among grains can be controlled, and the noise of the magnetic recording medium can also be reduced.
As explained above, in the present invention, reduction in thickness of the magnetic layer and noise can be accelerated, and thereby high recording density of magnetic recording medium can be realized. | A higher value of an anistropic magnetic feild can be acquired by using a magnetic material where Cr is not added as a material of a magnetic layer on which magnetic data is recorded. A magnetic recording medium can be manufactured through the processes of laminating an underlayer cosisting opf Cr-based non-magnetic material on a substrate, and then laminating, on this underlayer, a magnetic layer consisting of an alloy of at least one kind of non-magnetic material that is different from Cr and Co. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an improved electronic lock and particularly an improved electronic lock that employs a small power motor to drive the lock to reduce electric power consumption and voltage, and to increase the durability of batteries.
2. Description of the Prior Art
Conventional electronic locks generally employ only an electronic password to control unlocking of the lock. Such a design has many drawbacks in practical use, notably:
1. As the electronic lock controls unlocking and locking mainly through electronics, and it generally does not have keys for backup, in the event of power shortage, malfunction of electric circuits, or users forget the password, users cannot unlock the electronic lock by themselves. They have to ask the locksmith for help. It is not convenient and incurs extra cost.
2. Conventional electronic locks do not have well designed battery chambers. In the event of battery power running out, the whole electronic lock has to be disassembled for replenishing the batteries. It is not only inconvenient, parts (such as screws) are easily get lost during disassembly. In addition, electric circuits are easy to be damaged due to inadvertent disassembly.
In order to remedy the disadvantages mentioned above, Applicant has proposed a solution entitled: “Improved electronic lock” (U.S. Pat. No. 5,960,656). Although that patent can overcome the problems of conventional electronic locks, it uses solenoid valve as the main driving source. Such a design creates the following problems:
1. The operation of the solenoid valve requires sufficient electric power to generate the required magnetic force. When using batteries as the power supply for the electronic lock, the electric power of the batteries is consumed continuously. Hence its reliability is risky.
2. The solenoid valve requires electric power of 12V, and a step-up circuit is needed to boost the voltage from 12V to 50V. It consumes a lot of electric power.
SUMMARY OF THE INVENTION
In view of aforesaid disadvantages, the object of the invention is to provide an improved electronic lock that employs a motor as the power supply. The motor can function accurately at a low voltage, thus effectively overcomes the disadvantages of power draining that occurs to the solenoid valve. And durability of the batteries also increases.
The electronic lock according to the invention mainly includes an outer frame, an inner frame, a lock axle unit and a power unit.
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the invention.
FIG. 2 is an exploded view of the invention.
FIG. 3 is a schematic view of the invention in an operating condition, locked in a normal circumstance.
FIG. 4 is a fragmentary cross section according to FIG. 3 .
FIG. 5 is a schematic view of the invention in another operating condition, for unlocking.
FIG. 6 is a fragmentary cross section according to FIG. 5 .
FIG. 7 is a schematic view of the invention in yet another operating condition, for unlocking.
FIG. 8 is a cross section of the invention, showing locked in a normal circumstance.
FIG. 9 is a cross section of the invention, showing an unlocking circumstance.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2, the electronic lock of the invention mainly includes an outer frame 1 fastening to a locking dock 11 . The locking dock 11 has screw struts 111 located on one side to run through the lock stile from the outer side of a door to fasten to an inner frame 2 of the lock located on the inner side of the door.
The outer frame 1 includes a keypad 12 , a circuit board 13 located in the interior of the keypad 12 , and an outer handle 14 located on a lower section thereof. The outer handle 14 houses a lock core 19 therein (also referring to FIG. 8) and has a shaft opening 141 for coupling with a front rod 31 and a stub 334 of a front connection disc 33 of a lock axle unit 3 , and is movable therewith. In the interior of the outer frame 1 below the circuit board, there are a barrel seat 15 , a motor seat 16 and a lock axle compartment 17 for housing a power unit 4 and the lock axle unit 3 .
The inner frame 2 is installed on the inner side of the lock stile of the door, and has a battery chamber 211 located on an upper side for housing batteries and an inner handle 22 for users to control extension and retraction of the latch bolt 51 of a latch assembly 5 .
The invention has the following characteristics:
The lock axle unit 3 is housed in the lock axle compartment 17 of the outer frame 1 , and includes:
a front rod 31 coupling with a first spring 311 and running through a front retain plate 32 and a first round opening 333 of the front connection disc 33 , and having one end movable forwards when pressed by an inserting key and other end pushing a linkage block 34 ;
a front retain plate 32 being fastened to the outer frame 1 by coupling screw bolts A through apertures 321 formed thereon with screw holes B located on the outer frame 1 . The front retain plate 32 has at least one strut 322 for fastening to a rear retain plate 37 through screw bolts A. In the center of the front retain plate 32 , there is a second round opening 323 to allow a stub 334 located on the front connection disc 33 to run through. Below the second round opening 323 , there is a first arched slot 324 which has a first notch 325 located on the bottom rim in the middle thereof. On the left and lower corner of the front retain plate 32 , there is a hole 326 pivotally engaging with a stub shaft 352 of a coupling barrel 353 of a L-shaped lever 35 ;
a front connection disc 33 having four first grooves 331 formed on the perimeter thereof and an indented straight trough 332 formed in the center of the front side. The first round opening 333 is formed on the bottom of the trough 332 to communicate with the stub 334 located on other side of the front connection disc 33 ;
a linkage block 34 having an aperture 341 formed in the center thereof to allow a pintle 361 located on a rear connection disc 36 to pass through. The linkage block 34 is pressed by a second spring 342 in normal conditions to wedge in the straight trough 332 of the front connection disc 33 ;
a L-shaped lever 35 being located between the front retain plate 32 and the rear retain plate 37 , and having a vertical section 350 and a bottom section 354 . The L-shaped lever 35 further has a coupling barrel 353 located at the corner with two ends formed respectively a stub shaft 352 to engage respectively with the hole 362 on the front retain plate 32 and another hole 375 formed on the rear retain plate 37 such that the L-shaped lever 35 is turnable about a constant axis. The top end of the vertical section 350 is extended to form an U-shaped fender 355 which has a notch 351 to allow the spindle 412 of a motor 41 to pass through;
a rear connection disc 36 having four second grooves 362 formed on the perimeter thereof and a cylindrical strut 363 located in the center of the front side. The cylindrical strut 363 has an aperture 364 . The cylindrical strut 363 may couple with a coupling hole 391 formed in a linkage rod 39 which has an aperture 393 formed on one end thereof, then a pin 392 may be inserted into the hole 393 and the aperture 364 to fasten the rear connection disc 36 to the linkage rod 39 . The rear connection disc 36 further has a cross straight trough 365 corresponding to the straight trough 332 of the front connection disc 33 . The pintle 361 is located in the center of the cross straight trough 365 for passing through the aperture 341 formed on the linkage block 34 ;
a rear retain plate 37 having apertures 371 for fastening to the struts 322 of the front retain plate 32 by means of the screw bolts A to couple with the front retain plate 32 . The rear retain plate 37 has a third round opening 372 and a second arched slot 373 located below the third round opening 372 . The second arched slot 373 has a second notch 374 located on the bottom rim in the middle thereof. On the left and lower corner of the rear retain plate 37 , there is another hole 375 pivotally engaging with the stub shaft 352 of the coupling barrel 353 of the L-shaped lever 35 ;
a latch bolt 38 running through the arched slots 324 and 373 of the front and the rear retain plates 32 and 37 and is fastened to a nut 381 so that the latch bolt 38 may slide to the left and the right in the arched slots 324 and 373 , and move the front and the rear connection discs 33 and 36 . The latch bolt 38 is located in the notches 325 and 374 of the arched slots 324 and 373 in normal conditions; and
a linkage rod 39 having a coupling hole 391 formed on one end thereof to couple with the cylindrical strut 363 of the rear connection disc 36 and is fastened by the pin 392 , and other end running through a square opening 52 of the latch assembly 5 to engage with the inner handle 22 to link the movement between the latch bolt 51 of the latch assembly 5 and the inner handle 22 of the inner frame 2 ;
The power unit 4 is housed in the barrel seat 15 and the motor seat 16 of the outer frame 1 , and includes:
a motor 41 being housed in the motor seat 16 of the outer frame 1 and fastened by a lid 411 . The spindle 412 of the motor 41 may turn in one direction or in a reverse direction depending on the polarity of the input electric power supply. Therefore a pintle 413 mounted on the spindle 412 may move along the helical path of a third spring 43 housed in a sleeve 44 to move the sleeve forwards or rearwards;
a sliding plate 42 coupled an opening 441 of the sleeve 44 to prevent the third spring 43 from dropping out having a round hole 421 in the center to allow the spindle 412 of the motor 41 to pass through, and a jutting flap 422 extended from one side thereof to wedge in a retain slot 451 formed on a retain plate 45 ;
a third spring 43 housed in the sleeve 44 having two ends engaged with a wedge slot 442 of the sleeve 44 ;
a sleeve 44 being hollow for housing the third spring 43 and having a wedge slot 442 formed on one side thereof; and
a retain plate 45 fastened to an upper section of the barrel seat 15 of the outer frame 1 to cover the sleeve 44 . The retain plate 45 has a retain slot 451 for limiting the forward and rearward moving displacement of the jutting flap 422 of the sliding plate 42 .
By means of the construction set forth above, referring to FIGS. 3, 4 and 8 , when the electronic lock of the invention is locked in normal conditions, the linkage block 34 of the lock axle unit 3 is pushed by the second spring 342 in the normal conditions and is wedged in the straight trough 332 of the front connection disc 33 , and the latch bolt 38 drops into the notches 325 and 374 of the arched slots 324 and 373 of the front and the rear retain plates 32 and 37 due to gravity. Thus when an user turns the outer handle 14 of the outer frame 1 , only the front connection plate 33 of the lock axle unit 3 is driven. The rear connection plate 36 , linkage rod 39 and the latch bolt 51 of the latch assembly 5 cannot be moved. The electronic lock of the invention cannot be unlocked and is in a locked condition. To unlock the electronic lock of the invention, users may enter the correct password on the keypad 12 on the outer frame 1 to activate the circuit board 13 , and the motor 41 of the power unit 4 is activated and rotates. As the spindle 412 of the motor 41 rotates at a constant location and the sleeve 44 is movable, when the pintle 413 of the spindle 412 rotates along the helical path of the spring 43 , the sleeve 44 is pushed forwards. The U-shaped fender 355 of the L-shaped lever 35 is pushed by front end of the sleeve 44 (as shown in FIG. 6) and moved outwards. As a result, the bottom section 354 is tilted upwards to push the latch bolt 38 upwards into the arched slots 373 and 324 , and the grooves 331 and 362 of the front and rear connection plates 33 and 36 (as shown in FIG. 5 ). In such a condition, when the user turns the outer handle 14 of the outer frame 1 , the front and rear connection plates 33 and 36 and the linkage rod 39 of the lock axle unit 3 are driven to move the latch bolt 51 of the latch assembly 5 , and the lock may be unlocked and opened (as shown in FIG. 7 ).
In the event that the user has forgotten the password or battery power in the electronic lock is exhausted, and the electronic lock cannot be activated, the user may insert the key 6 into the key way (as shown in FIGS. 8 and 9) to push the front rod 31 of the lock axle unit 3 . The linkage block 34 may be pushed and moved between the straight trough 332 of the front connection disc 33 and the cross straight trough 365 of the rear connection disc 36 of the lock axle unit 3 . Then the outer handle 14 of the outer frame 1 may be turned to drive the front and the rear connection discs 33 and 36 , and in turn to drive the linkage rod 39 and the latch bolt 51 of the latch assembly 5 to accomplish the unlocking (operations of inserting the key into the key way are known in the art, thus are omitted in the drawings and descriptions).
While the preferred embodiment of the invention has been set forth for the purpose of disclosure, modifications of the disclosed embodiment of the invention as well as other embodiment thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention. | An improved electronic lock requires a low power and consumes less electricity including an outer frame, an inner frame, a lock axle unit and a power unit. The outer frame is fastened to the outer side of a lock stile of a door. The outer frame has an outer handle, a keypad and a key way located on the exterior, and has the interior for housing the lock axle unit and the power unit to couple with the inner frame. The power unit includes a motor, a spring, a sleeve, a sliding plate and a retain plate. The power unit is coupled with a L-shaped lever to generate lever movements. Users may enter an electronic password to activate the motor to perform locking and unlocking function. The construction greatly reduces electric power: consumption of batteries, and lowers electric voltage, and increase the durability of the batteries. | 8 |
This application claims the benefits of Provisional Patent Application Ser. No. 60/773,328 filed on Feb. 15, 2006.
FIELD OF THE INVENTION
The present invention is related to devices that control vehicular access through a fixed-width roadway. More particularly, the invention addresses devices that control access by damaging one or more of the tires of an unauthorized vehicle attempting to drive past a control point.
DESCRIPTION OF THE PRIOR ART
Car tire deflators are known in the art. A tire deflator typically has sharp tines designed to puncture one of the car's tires if the car is driven over the deflator. There are two basic types of deflators—fixed and controllable.
Fixed deflators are used to control the flow of traffic and to limit its direction. Fixed deflators may be bi-directional or unidirectional. A bi-directional fixed deflator prevents traffic past the device in either direction, in effect closing a roadway to vehicular traffic. A unidirectional deflator allows traffic in one direction, but blocks it in the opposite direction.
A typical application for fixed unidirectional deflators is for mounting in entrance lanes of a parking area. The deflator discourages vehicles from exiting through an unguarded entrance and directs them to a manned exit lane. A typical fixed uni-directional deflator is described in U.S. Pat. No. 3,783,558 in the name of Keator. The deflator relies on the geometry of the tines to pose a threat in one direction and to act benignly in the other direction. There is no active mechanism involved that activates and deactivates the functioning of the tines.
Controllable deflators differ from fixed deflators in that their tire-puncturing action can be enabled or disabled. This distinguishing feature makes controllable deflators suitable for controlling vehicular access past a control point. To the extent that such devices control vehicular access on a roadway, they can be used interchangeably, or in conjunction with, gates or barriers. Controllable deflators differ in the method by which the tines are rendered inoperative (“safe”) or operative (“enabled”).
U.S. Pat. No. 4,101,235 in the name of Nelson discloses a controllable deflator used for allowing authorized drivers to have access to a parking lot. The tines swivel on a shaft perpendicular to the flow of traffic. When the device is enabled, the tines are erect and facing the traffic. Any attempt to drive over them will result in the tines embedding themselves into the rubber of the tires. When the device is set to the safe mode, the tines are essentially prone and pose no threat to the tires passing over them. The change between the enabled and the safe states is achieved through an electric motor that rotates the shaft on which the tines are mounted. The mechanism is large, needs to be installed next to the traffic lane, and requires electrical power to operate. This in turn requires trenching and bringing external power to the unit.
U.S. Pat. No. 5,890,832 in the name of Soleau discloses a controllable deflator in which the spears swivel individually on an axis perpendicular to the length of the device. A common slider cam pushes the spears up when it is desired to enable the deflator. This system offers a lower profile, and can be installed on the surface of the roadway. However, it requires substantial power to raise the spears, which dictates trenching and the cost of bringing in external power to the device. It also requires a heavy structure to support and activate the spears, because the moving parts must withstand the heavy forces of vehicles.
A common concern when installing devices with sharp tines, spikes or spears is the danger that they may pose to pedestrians. In some localities, notably Japan, the use of controllable deflators is discouraged due to concerns about pedestrian safety. Patent publication WO 02/081824 A1 in the name of Pendlebury discloses a method for protecting pedestrians from being hurt by a gate that includes barbs designed to capture and retain a car that forces its way through a barrier. A perforated plate is permanently placed in front of the barbs, to prevent pedestrians from contacting the barbs. When a car speeds into the barrier with the intent to ram its way through the roadblock, the guard plate yields and allows the barbs to lodge into the car and hold the car captive.
The Pendlebury device is intended as a one-time-use arresting barrier, and requires a significant kinetic energy from a speeding car to activate the barbs. Another limitation of the Pendlebury device is that in order to remove the road block, the entire assembly of the barbs and the guard plate must be swiveled out of the way of the traffic. This requires a complex and heavy structure and does not lend itself to a commercially viable application as a deflator.
U.S. Pat. No. 6,045,293 in the name of Dickenson discloses a uni-directional controllable deflator system with a pedestrian-friendly feature. The individual tines are covered by a protective member in the form of a sleeve or a cap. Under the pressure of a tire, the protective cover is forced down (in the case of the sleeve) or crushed (in the case of the cap), allowing the tire to come into contact with the tines. The tines with their covers are mounted to a shaft that rotates the entire assembly to a safe position when passage is to be allowed.
One of the limitations of the Dickenson system is that each tine must have its own protective guard, and the guard has to be able to resist the forces of an individual stepping on it. Due to practical size considerations, it is very difficult to generate such resistive forces in a small space. It is likely, therefore, that the protective cover must be of the self-destruct type, relying on the hardness of the cap to be punctured by the tire. That results in a single-use part, with the attendant drawback of a service call requirement after each attempted breach.
Another drawback of the Dickenson system is that the entire assembly must be rotated to disable the deflator. This dictates a heavy shaft, large mass and size, and the requirement for an external power source to operate the motor that rotates the shaft.
When a deflator is used as an access control, it is essential that an approaching driver be aware of the state of the deflator, i.e., whether it is safe to drive through the associated gate or whether the deflator is enabled. One of the common methods to convey this information to the driver is to combine the deflator with an associated barrier or gate. Combination deflators and gates are known in the art. U.S. Pat. No. 4,318,079, also in the name of Dickenson, teaches a combination horizontal gate and deflator, where the two elements move in unison so that the deflator is armed when the gate is raised to block traffic. The shortcomings of Dickenson's system are that it requires outside power to operate a motor, and that the tines are exposed whenever the gate is raised. The sharp tines of the deflator pose a threat to pedestrians, and a malfunction in the complex mechanical linkages between the deflator and the motor can cause the deflator to stay raised even as the gate is lowered, causing damage to authorized cars passing over the device. Another limitation of the Dickenson system is that, once a car forces its way through the gate, the gate will break and will have to be replaced. In addition to the cost or replacing the gate, there may be a long down-time until the gate is repaired.
Thus it is an object of our invention to provide a vehicular access control system that can be installed on the surface of a roadway without trenching or digging, which can be powered by small batteries to eliminate the need to run power to the unit, and which includes a deflator that is pedestrian-safe at all times.
An additional object of our invention is to make the deflator compatible and useable with a self-powered barrier, so that the entire gate system (which comprises the barrier and the deflator) can be self contained and easily installed without external power, digging or wiring.
SUMMARY OF THE INVENTION
The present invention is a controllable tire deflator for use as vehicular access control apparatus. The apparatus switches between two states, one intended to impede the flow of traffic through it, and the other to allow traffic to flow through it. A series of sharp tines, or spears, placed at intervals across the roadway, is allowed to come into contact with the tires of a passing car when the apparatus is in the enabled (impeding) state. Should a car drive over the apparatus in this enabled state, the tines will penetrate the tires and damage them to the point where further driving of the vehicle will be difficult.
The apparatus can be placed in the safe (non-impeding) state by inserting a metal plate above the tines. The tires can then ride over the plate, without damage, thus allowing passage.
In order to accommodate surface mounting of the apparatus, two plates form a protective tent over the tines. The plates are connected at the apex with a hinge. The tines are placed under one of the plates (the front plate) on a base plate. The front plate is attached to the base plate through a second hinge. Thus the front plate is attached to the base plate with one hinge, and to the other (rear) plate that forms the protective tent with another hinge. A series of windows in the front plate is aligned with the tines, allowing the tines to show through the plate when the front plate is resting on the base. If the plate is allowed to rest on the base, or allowed to collapse under the weight of a car to rest on the base, the tines will be exposed and will damage a passing tire.
When the apparatus is placed in the safe state, a shutter-like plate comes between the front plate and the tines. In this state, the front plate cannot collapse to the ground, as it is supported by the shutter plate and by the tines. A car can then drive over the front plate which now acts as a ramp. Once the car has reached the apex of the protective tent, the tire continues down the rear plate, rolling down to ground. An arrangement of springs keeps the two plates above the tines, preventing the plates from collapsing from their own weight, or even from the weight of a pedestrian that may step on the protective plates.
The shutter that controls the two states of the apparatus can be driven by a small electric motor. Together with a suitable battery and electronic package, the apparatus becomes a self-contained wireless remote controlled access control point. Alternatively, the motor can be powered and controlled through an external electrical cable attached to external switches or a controller.
Broadly speaking, the invention is a vehicle, e.g., a car, access control device that has a plurality of vertically disposed tire piercing members or spears. An upwardly spring-biased tent-like covering over the spears protects pedestrians, the weight of a pedestrian being insufficient to force the covering from an upper position that covers the spears to a lower position where the spears are exposed, but the weight of a car being sufficient to do so. A control element in the form of a shutter or guard plate is movable by a remotely controlled actuator between a first position in which the spears are enabled to pierce the tires of a passing car (by allowing the weight of a passing vehicle to force the covering to move from its upper position to its lower position) and a second position in which the spears are disabled from piercing the tires of a passing car (by preventing the covering from lowering under the weight of a passing vehicle). The guard plate and the covering both have windows to allow the spears to pass therethrough when the guard plate is in the first position, the guard plate blocking the windows in the covering when the guard plate is in its second position.
A remotely-controlled battery-operated actuator mechanism moves the guard plate between its two positions, and the actuator can be locked in two positions corresponding to the first and second positions of the guard plate. The actuator operates to change the position of the guard plate to the position represented by the most recent remote control command, but it also determines whether the current position of the guard plate is that represented by the most recent remote control command and, if it is not, causes the position of the guard plate to be switched without the need for another remote control command.
The entire device sits on a base on which the spears are permanently and immovably mounted, all other elements of the device also being mounted on the base and the base being surface-mountable on a roadway without the need for digging into the roadway. An associated barrier indicates to a driver whether it is safe to go over the device, the actuator directly controlling the barrier to be raised or lowered in accordance with the current position of the guard plate determined by the actuator. The device has a width that is sufficient to pierce the tires on just one side of a car, the device having an overall configuration that allows two such devices to be placed in line to pierce the tires on both sides of a car.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the invention, reference is made to the following description, when taken in connection with the drawings, in which:
FIG. 1 is a perspective view of the tire deflator apparatus according to our invention;
FIG. 2 is a perspective cutout view of the deflator tines and the components surrounding them, shown with the apparatus in the safe state;
FIG. 3 is a perspective view of the apparatus in the enabled state, with the protective plate depressed;
FIG. 4 a is a view of the motor assembly that controls the shutter, with the shutter in the enabled state;
FIG. 4 b is a view of the motor assembly that controls the shutter, with the shutter in the safe state;
FIG. 4 c is a view of the gear wheel detail and the sensor that controls operation of the motor;
FIG. 5 is a block diagram of the electronic module that controls the motor operation;
FIG. 6 is a flow chart of the logic that controls the motor operation; and
FIG. 7 is a perspective view of the apparatus installed in combination with a wire-free barrier.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Tines Assembly
With reference to FIG. 1 , the apparatus 1 comprises a base 2 , a front plate 3 , a rear plate 4 , a motor housing 5 and an end-cap 6 . Within the metal motor housing 5 a plastic cover 5 a provides a path for radio signals to the radio receiver inside the housing. While the apparatus is equally effective in controlling vehicular traffic moving in either direction 7 or direction 8 , the description herein will refer to direction 7 as the “entry” direction, and direction 8 as the “exit” direction.
With reference to FIG. 2 , each stationary tine or spear 21 is permanently and fixedly mounted on base 2 . Alternatively, however, the tines may be installed so that they can slide laterally on the base. Plate 3 is attached to base 2 through hinge 22 . Plate 4 is attached to plate 3 through hinge 23 , and rests on base 2 at its other end. A series of springs 24 are interspersed between the hinge sections 22 a . The springs 24 exert a force on plate 3 that offsets the weight of the plates 3 and 4 , and keep these plates up. The upward movement of plate 3 causes the bottom end of plate 4 to slide toward the center of the device (toward the tines), until stopped by bracket 25 engaging bracket 26 . Bracket 25 is an integral part of plate 4 , while bracket 26 is an integral part of base 2 . The force exerted by springs 24 on plate 3 can be overcome by a force 27 applied vertically to the apex of the tent created by plates 3 and 4 . In the preferred embodiment of our invention, the minimum value of force 27 required to collapse the tent formed by the plates is greater than the weight of an adult who can be expected to step on the plates. This allows pedestrians to step on the tent without causing the plates to move, thus keeping pedestrians safe from tines 21 that are beneath the tent.
Plate 3 incorporates a slide channel 28 and a shutter or guard plate 29 . The plate, the slide channel and the shutter are all provided with windows which align with the tines ( FIG. 4 a ). This allows plate 3 to rotate on hinge 22 and move past the tines until it lies flat on the base plate 2 , as indicated in FIG. 3 . In this figure, the apparatus is shown with its protective plates 3 and 4 collapsed to expose the tines 21 . The two ends of the apparatus are motor housing 33 and end-housing 34 . These are stationary at all times.
Shutter 29 can slide laterally in channel 28 , until its windows 29 w ( FIG. 3 ) no longer align with the tines. In that case, the solid sections on the shutter, between the windows, will be positioned directly above the tines. If force is applied in direction 27 , overcoming the counter force created by springs 24 , plate 3 will start to move in the direction 27 . However, once shutter 29 comes in contact with the tines, no further downward motion will be possible. Tines 21 are shaped so that the shutter comes in contact with as large an area of the tines as possible, to prevent the tines from being damaged by the force exerted on them when a car drives over the plate 3 in the safe mode.
The shutter or guard plate 29 thus moves in two directions. Movement in the horizontal direction (parallel to the ground) determines whether the windows are aligned with the tines such that the overall device is in its enabled state in which the tines become operative should a car move over them. Movement of the guard plate in the vertical direction (along with plate 3 that carries it) takes place when the device is in its enabled state and a car passes over it.
Motor Assembly
The motor assembly controls the alignment of the tines 21 and the windows 29 w . When the windows are aligned with the tines, the apparatus is enabled (a car's weight will close the tent and expose the tines); when the windows are offset from the tines, the apparatus is safe (the shutter prevents plate 3 from folding around the tines).
With reference to FIG. 4 a , motor 40 drives gear wheel 41 through intermediary gears, in order to reduce the speed of gear 41 and increase its available torque. Arm 42 is held against the center of gear 41 by spring 49 acting through linkage 44 . Shutter 29 is in its leftmost position. In this position the windows 29 w in the shutter align with the tines 21 and the deflator is in the enabled state. (The tines 21 can be seen through the windows 29 w in FIG. 4 a .)
With reference to FIG. 4 b , motor 40 rotates gear wheel 41 counter-clockwise until cam 41 d on the gear wheel pushes arm 42 to the right. Linkage 44 travels in direction 46 , pulling arm 48 with it. Arm 48 swivels on pin 48 a , forcing the shutter 29 to move in direction 47 . As shown in FIG. 4 b , the windows 29 w in the shutter are no longer aligned with the tines, and the apparatus is in the safe mode. (The tines 21 can no longer be seen through the windows 29 w in FIG. 4 b .)
With reference to FIG. 4 c , gear 41 is provided with tabs 41 e and 41 f . These tabs (which pass under arm 42 and, unlike cam 41 d , do not engage the arm) are used to block optical sensor 60 when the gear has reached either of its stop positions. The sensor 60 is of the transmissive type; it is shaped like a “U”, with an IR transmitting diode in one leg of the U, and a receiving IR diode in the opposite leg. As the tabs 41 e or 41 f rotate, they come in between the sensor's IR diodes and thus can block them. When a tab blocks the sensor, the output of the sensor is high. When there is no blockage of the sensor, the output of the sensor is low. A transition from low to high occurs when a tab just moves in to block the sensor.
The safe position is when cam 41 d is in contact with arm 42 ( FIG. 4 b ). The enabled position is 180 degrees of rotation away ( FIGS. 4 a and 4 c ). Motor 40 is powered through an electronic module. This module is a combination radio receiver and motor controller. The radio receiver decodes radio commands from one or more remote transmitters and operates the motor so that it rotates 180 degrees after each accepted command. Thus the apparatus will toggle between its two states with each accepted radio command.
When a valid toggle command is decoded by the radio, motor 40 is started. Power to the motor stays on until the leading edge of tab 41 e or tab 41 f blocks the sensor 60 . Once the sensor is blocked by either of the tabs, the motor stops and the new state is maintained until the next toggle command. When a new command is received, the motor is started and allowed to run until the opto-sensor reports to the electronic module that a transition from unblocked to blocked has occurred.
An alternative mode of control requires that the apparatus respond discretely to either of two different commands, an ‘enable’ command and a ‘safe’ command. In order to achieve this requirement, the controller needs to know at any point whether gear 41 is stopped in the enable position or in the safe position. In the preferred embodiment of our invention, this is achieved through the use of a slot 41 g in tab 41 f . FIG. 5 is a block diagram of the control circuit of the invention. The controller is powered by battery 57 . In our preferred embodiment, the battery is comprised of four alkaline D cells that can power the system for well over one year under normal use. The controller supplies power to the radio receiver. When a valid RF signal is received by radio receiver 58 , it sends a signal over conductor 58 a to the controller 59 . The controller 59 activates the motor through line 59 a . The sensor 60 reports over line 59 b when the motor gear reaches a predefined position. Transmitter 56 is powered by the controller through line 56 a . The transmitter is used to provide feedback to external devices (not shown) on the status of the deflator apparatus.
FIG. 6 is a flow chart showing the logic implemented in the controller software to achieve the discrete control commands for enabling and disabling the apparatus.
With reference to FIG. 6 , when a radio command is received and decoded, the motor actuation logic starts at point 101 . If the command is the same as the previous command, it is ignored and the routine terminates at 103 . If the new command received is different from the previous command, then in step 104 a subroutine 110 is called. This subroutine starts the motor and starts a timer A ( 111 ). The logic then waits for a transition from low to high on the opto-sensor 60 ( 112 ), which transition occurs when either tab 41 f or tab 41 e enters the opto-sensor and blocks the sensor's optical beam, or when tab 41 f is in the opto-sensor and moves slightly until the trailing edge of slot 41 g in tab 41 f reaches the optical beam in the sensor. (When the slot first reaches the optical beam the output of the sensor goes from high to low; at the trailing edge of the slot, when the beam is blocked once again, the output goes from low to high.) A test is performed to determine if the low-to-high transition occurs before timer A reaches a preset time t 1 ; the time t 1 is much shorter than the time it takes for gear 41 to travel 180 degrees. If a transition occurs before the timer times out, it means that tab 41 f with its slot is within the sensor and the gear 41 has just left the safe state ( FIG. 4 b ) and is rotating toward the enabled state ( FIGS. 4 a and 4 c ). The logic proceeds to step 114 , where a variable S is set to 0; this indicates that the device will soon be in the enabled state. If the timer A times out ( 113 ) before a transition is detected in step 112 , the logic reaches step 115 where the variable S is set to 1 to indicate that the device will soon be in the safe state.
In either case, after step 114 or 115 , the logic waits in step 116 for the sensor transition that indicates that the next tab on gear 41 has just reached the sensor. As soon as the low-to-high transition is detected, the logic proceeds to step 117 where the motor is stopped and the subroutine exits in step 118 . Control is now returned to the main routine at step 105 (following the call to the motor subroutine). The logic now compares the received command with the actual position of the gear 41 , as recorded in the S variable that is returned by subroutine 110 . If the position of gear 41 matches the command, the mission has been successfully accomplished and the routine is terminated. If the command was “enable”, the logic proceeds to step 107 . If the variable returned was S=0, it means that the gear is now in the enabled position, allowing the routine to terminate in step 108 . Likewise, if the command was “safe”, the logic proceeds to step 106 . If the motor subroutine returned a value of 1 for the variable S, it means that the gear achieved the desired position and the routine terminates in step 108 .
If in step 107 or step 106 there is a mismatch between the command and the S value, the routine proceeds to step 104 which runs the motor subroutine again. This step automatically synchronizes the gear position with the received command, to correct potential errors that can be caused during power up or by other error sources.
The movement of the shutter 29 between the enabled state and the disabled (safe) state provides a visual indication to the entering driver as to the state of the apparatus. The shutter may be painted with a bright color, for example green, while the tines may be painted a bright red color. When the apparatus is in the enabled mode, the red tines show through the slots. When the apparatus is in the safe state, the green shutter shows through the windows in the front plate. Additional means of indicating the state of the apparatus may include a small flag, a large disc with two colors, and the like.
Operation With Wireless Barrier
As is common in the industry, deflators are used in conjunction with barriers to create a complete gate system. The barrier acts as a visual flag to prevent an unsuspecting driver from entering the premises, while the deflator intimidates a driver who may intentionally want to overrun the gate.
Our United States patent application 2004/0165949A1 describes a wireless and wire-free barrier that uses the weight of a vehicle as the motive energy to raise the barrier through a remote control command. By combining the wireless barrier and the wireless deflator, a complete wireless gate system can be assembled.
FIG. 7 shows a barrier 71 and a deflator 72 placed side by side to block vehicular access. In operation, the deflator is programmed to respond to a remote controller and the barrier is programmed to respond to radio commands from the deflator. When the deflator receives a valid command to toggle the gate, it proceeds with the execution as depicted in FIG. 6 . Once it has completed the execution (e.g., when entering step 108 ), the deflator can send a coded transmission to the barrier, instructing it to toggle. An advantage of having the tire deflator control the barrier is that since the barrier acts as a flag, indicating to the entering or exiting driver whether it is safe to do so, the barrier cannot misinform the public about the state of the deflator since the deflator directly controls the barrier to be raised or lowered in accordance with its current state.
An alternative way is to provide a wired connection between the two devices, where the deflator directly controls the barrier. If the barrier is powered, then a similar connection can also be used to bring in outside power for the deflator.
It is expected that deflators will be manufactured in sections, for example, 36 inches wide. In narrow access points, it will be sufficient to use just one such deflator. For wider access points, two or more sections can be installed in line, and through a simple linkage operated together.
Although the invention has been described with reference to a particular embodiment, it is to be understood that this embodiment is merely illustrative of the application of the principles of the invention. Numerous modifications may be made therein and other arrangements may devised without departing from the spirit and scope of the invention. | A vehicle access control device having vertically-disposed tire-piercing spears. An upwardly spring-biased tent-like covering over the spears protects pedestrians, the covering being movable between a lower position in which the spears are exposed and an upper position in which the spears are covered. The weight of a pedestrian is insufficient to force the covering from the upper position to the lower position but the weight of a car is sufficient to do so. A remotely-controlled horizontally-movable plate selectively enables and disables the tent-like covering to lower under the weight of a car. The plate and the covering both have windows to allow the spears to pass therethrough when the covering is lowered, the plate blocking the windows in the covering when the lowering of the covering is disabled. The device is surface-mountable on a roadway without the need for digging into the roadway. | 4 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates to a displacement detecting device, a scale calibrating method and a scale calibrating program applied to a linear encoder, a rotary encoder, etc.
[0003] 2. Description of the Related Art
[0004] Generally, measurement error of a displacement measuring device such as an encoder is evaluated before shipment. A highly accurate displacement sensor such as a laser interferometer is used for a reference for error evaluation. The thus obtained error data are shipped in the form of a pre-shipment inspection table together with the encoder so as to be used as important data for warranting performance of the encoder.
[0005] However, the scale of the encoder may be distorted according to the material and length of the scale and the fixing method when the scale of the encoder is attached to an application such as a machine tool, a measuring device, etc. In some cases, non-negligible level measurement error in regard to a required specification may be caused by the generated distortion of the scale so that reliability of error data evaluated in advance will be spoiled.
[0006] As a method for solving this problem, it is thought of that a reference displacement sensor is set up in a user's application to apply on-machine calibration to the measurement error of the encoder. It is however undesirable that a burden is imposed on the user in consideration of the labor for setting up the displacement sensor and the price of the highly accurate displacement sensor.
[0007] On the other hand, for example, methods for self-calibration measurement error on graduations of a scale (JP-A-2008-224578 and “Satoshi Kiyono, “Intelligent Precision Measurement”, The Japan Society for Precision Engineering, 2009, Vol. 75, No. 1, pp. 89-90”) are known in this type displacement detecting device. Use of these self-calibration methods permits measurement error of an encoder to be calibrated without any highly accurate displacement sensor set up in an application.
[0008] However, when configuration is made in such a manner that a plurality of sensors are arranged at intervals of predetermined distance as disclosed in JP-A-2008-224578 and “Satoshi Kiyono, “Intelligent Precision Measurement”, The Japan Society for Precision Engineering, 2009, Vol. 75, No. 1, pp. 89-90”, the sampling interval of measurement error becomes equal to the pitch of arrangement of the sensors. For this reason, measurement error having a period not longer than twice as long as the arrangement pitch cannot be restored correctly, so that the frequency of measurement error allowed to be calibrated is limited.
[0009] Although it may be thought of that the pitch of arrangement of the sensors is narrowed to solve this problem, such a minimum distance that the sensors do not interfere with one another physically is required as the arrangement pitch. For this reason, narrowing the pitch of arrangement of the sensors is limited.
[0010] Moreover, use of a highly accurate displacement sensor such as a laser interferometer or preparation of a reference sensor or the like is not desirable because configuration becomes uselessly expensive. When measurement error of a non-negligible level is caused by distortion of the scale at the time of mounting or the like, it may be necessary to set up the reference displacement sensor again and a lot of cost and labor is still required.
SUMMARY
[0011] The invention is accomplished to solve such a problem and an object of the invention is to provide a displacement detecting device, a scale calibrating method and a scale calibrating program which can be formed easily and inexpensively without any laser interferometer, any reference scale, etc. so that measurement error on graduations can be calibrated accurately.
[0012] A displacement detecting device according to the invention includes: a scale which has an optical lattice; a detecting unit which is disposed so as to be movable in a scanning direction relative to the scale and which has n(n is an integer not smaller than 3) detection portions, inclusive of at least a first detection portion, a second detection portion and a third detection portion, arranged in the scanning direction for detecting position information from the optical lattice; and a calculating portion configured to obtain a self-calibration curve on graduations of the scale by specifying positions of the detection portions and calculating measurement error based on the position information detected by the detecting unit; wherein: the detecting unit is provided so that a distance between the first detection portion and the second detection portion and a distance between the second detection portion and the third detection portion are different from each other and do not form an integral multiple; and the calculating portion obtains the self-calibration curve on the graduations of the scale by repeating operation of moving the detecting unit in the scanning direction until position information detected by one of the first to third detection portions is detected by another detection portion, and calculating measurement error based on the detected position information and a distance between the detection portions which have detected the position information.
[0013] In this configuration, the sampling interval which is an interval for acquiring output data can be set to be shorter than the distance between detection portions of the detecting unit, so that a self-calibration curve having finer graduations can be obtained. Accordingly, measurement error can be corrected accurately by an inexpensive configuration.
[0014] In one embodiment of the invention, a difference of the distance between the first detection portion and the second detection portion from the distance between the second detection portion and the third detection portion is shorter than a minimum distance d in which the n detection portions can be arranged physically.
[0015] In another embodiment of the invention, the calculating portion reciprocates the detecting unit in the scanning direction and acquires the position information.
[0016] In a further embodiment of the invention, the displacement detecting device further includes: a storage unit which stores the self-calibration curve; wherein: the calculating portion corrects measurement error of the graduations by referring to the self-calibration curve stored in the storage unit.
[0017] A scale calibrating method according to the invention is a scale calibrating method in a displacement detecting device including a scale which has an optical lattice, a detecting unit which is disposed so as to be movable in a scanning direction relative to the scale and which has n(n is an integer not smaller than 3) detection portions, inclusive of at least a first detection portion, a second detection portion and a third detection portion, arranged for detecting position information from the optical lattice so that a distance between the first detection portion and the second detection portion and a distance between the second detection portion and the third detection portion are not different from each other and do not form an integral multiple, and a calculating portion configured to obtain a self-calibration curve on graduations of the scale by specifying positions of the detection portions and calculating measurement error based on the position information detected by the detecting unit, the method including: the detecting step of repeating operation of moving the detecting unit in the scanning direction until position information detected by one of the first to third detection portions is detected by another detection portion; the calculating step of obtaining the self-calibration curve on the graduations of the scale by calculating measurement error based on the detected position information and a distance between the detection portions which have detected the position information; and the correcting step of correcting the position information of the optical lattice by referring to the obtained self-calibration curve.
[0018] A scale calibrating program according to the invention is a scale calibrating program for making a computer execute a scale calibrating method in a displacement detecting device including a scale which has an optical lattice, a detecting unit which is disposed so as to be movable in a scanning direction relative to the scale and which has n(n is an integer not smaller than 3) detection portions, inclusive of at least a first detection portion, a second detection portion and a third detection portion, arranged for detecting position information from the optical lattice so that a distance between the first detection portion and the second detection portion and a distance between the second detection portion and the third detection portion are not different from each other and do not form an integral multiple, and a calculating portion configured to obtain a self-calibration curve on graduations of the scale by specifying positions of the detection portions and calculating measurement error based on the position information detected by the detecting unit, the program including: the detecting step of repeating operation of moving the detecting unit in the scanning direction until position information detected by one of the first to third detection portions is detected by another detection portion; the calculating step of obtaining the self-calibration curve on the graduations of the scale by calculating measurement error based on the detected position information and a distance between the detection portions which have detected the position information; and the correcting step of correcting the position information of the optical lattice by referring to the obtained self-calibration curve.
[0019] According to the invention, it is possible to make configuration easily and inexpensively so as to be able to calibrate measurement error on graduations of a scale accurately.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawing which is given by way of illustration only, and thus is not limitative of the present invention and wherein:
[0021] FIG. 1 is a schematic view showing a configuration of a photoelectric encoder which forms a displacement detecting device according to an embodiment of the invention.
[0022] FIG. 2 is a view for explaining a basic principle of self-calibration on graduations of a scale.
[0023] FIG. 3 is a view for explaining the basic principle.
[0024] FIG. 4 is a view for explaining a configuration of a detecting unit in the photoelectric encoder.
[0025] FIG. 5 is a view for explaining steps in the detecting unit.
[0026] FIG. 6 is a view for explaining operation based on simulation models of detecting units according to Example of the invention and Comparative Example.
[0027] FIG. 7 is a view for explaining operation based on the simulation model of the detecting unit according to Example.
[0028] FIG. 8 is a view for explaining a configuration of a detecting unit in a photoelectric encoder which forms a displacement detecting device according to another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] A displacement detecting device, a scale calibrating method and a scale calibrating program according to embodiments of the invention will be described below in detail with reference to the accompanying drawings.
[0030] FIG. 1 is a schematic view showing a configuration of a photoelectric encoder which forms a displacement detecting device according to an embodiment of the invention. As shown in FIG. 1 , the photoelectric encoder 100 has a scale 10 , a detecting unit 20 , and a calculating portion 30 . For example, the photoelectric encoder 100 is formed as a reflective type in this embodiment.
[0031] For example, the scale 10 is constituted by a tape scale and has position information for detecting positions of measurement points of detection portions (first to third detection portions) 21 , 22 and 23 which form the detecting unit 20 . The scale 10 is provided so that light irradiated from the detection portions 21 to 23 of the detecting unit 20 is reflected toward the detection portions 21 to 23 . Incidentally, n (n is an integer not smaller than 3) detection portions may be provided.
[0032] As shown in FIG. 1 , the scale 10 has a rectangular film-like board 11 , and a track 12 provided on the board 11 . The longitudinal directions of the board 11 are moving directions (scanning directions X) of the scale 10 relative to the detecting unit 20 at the time of measurement.
[0033] The track 12 is constituted by patterns 12 a . The patterns 12 a are patterns arranged at intervals of a predetermined pitch (e.g. in the order of μm) along the scanning directions X so that bright portions or dark portions are arranged periodically.
[0034] The detecting unit 20 is formed so that the detecting unit 20 can be moved in the scanning directions X relative to the scale 10 . The respective detection portions 21 to 23 detect position information from the scale 10 . For example, the respective detection portions 21 to 23 are arranged so that the distance between a measurement point of the first detection portion 21 and a measurement point of the second detection portion 22 is the minimum physically allocable distance d, and the distance between a measurement point of the second detection portion 22 and a measurement point of the third detection portion 23 is a distance α i d (α i (i=2, 3, . . . , n−1)) larger than the minimum distance d. Incidentally, α i is a non-integer constant larger than 1.
[0035] Specifically, the respective detection portions 21 to 23 irradiate light onto the scale 10 (track 12 ) and receive the light reflected from the scale 10 . The detecting unit 20 detects position information of measurement points of the respective detection portions 21 to 23 based on the light received by the respective detection portions 21 to 23 .
[0036] The calculating portion 30 specifies the positions of the measurement points of the respective detection portions 21 to 23 based on the detected position information. The calculating portion 30 calculates measurement error on graduations of the scale 10 detected by the respective detection portions 21 to 23 and obtains a precision curve (self-calibration curve). For example, the calculating portion 30 is constituted by a built-in CPU of a computer which stores the obtained self-calibration curve in a storage portion 31 , reads a scale calibrating program from the storage portion 31 and executes the program to thereby perform a process of correcting measurement error on the graduations of the scale 10 or achieve various kinds of operations, for example, by referring to the self-calibration curve.
[0037] FIGS. 2 and 3 are views for explaining a basic principle of self-calibration on graduations of the scale. As shown in FIG. 2 , a detecting unit 200 having a detection portion 201 and a detection portion 202 disposed side by side along a scale 209 having pitch displacement due to distortion is prepared first. For example, the distance between measurement points of the detection portions 201 and 202 is set as d, and the outputs of the detection portions 201 and 202 are set as m 1 (x) and m 2 (x) respectively. Assuming now that f(x) is measurement error, then the output m 1 (x) is given as m 1 (x)=x+f (x) and the output m 2 (x) is given as m 2 (x)=(x+d)+f (x+d).
[0038] For measurement, the detecting unit 200 is moved (stepwise) at intervals of a predetermined pitch along a scanning direction X, and the outputs m 1 (x) and m 2 (x) of the detection portions 201 and 202 are sampled stepwise. When the number of steps required for scanning the whole length of the scale 209 is n and the amount of each step given to the detecting unit 200 is D STEP , the outputs m 1 (D STEP ·i) and m 2 (D STEP ·i) of the detection portions 201 and 202 at the i-th step (i=0, 1, . . . , n) are given by the following expressions (1) and (2) respectively.
[0039] [Numeral 1]
[0000] m 1 ( D STEP ·i )= D STEP ·i+f ( D STEP ·i ) (1)
[0040] [Numeral 2]
[0000] m 2 ( D STEP ·i )= D STEP ·i+d+f ( D STEP ·i+d ) (2)
[0041] Accordingly, it is found that the output m 2 (D STEP ·i) has an offset of d compared with the output m i (D STEP ·i). Incidentally, the distance d between measurement points of the detection portions 201 and 202 needs to be obtained by some method in advance.
[0042] When the detecting unit 200 is moved stepwise in one (e.g. in a rightward direction in the drawing) of the scanning directions X, the amount of each step is controlled so that the output m 1 (D STEP ) of the detection portion 201 disposed on the rear side in the moving direction is aligned with the output m 2 (0) of the detection portion 202 disposed on the one-step preceding side in the moving direction as shown in FIG. 3 . On this occasion, the distance d between measurement points of the detection portions 201 and 202 is known. Accordingly, when the output of the detection portion 201 becomes equal to the output of the detection portion 202 at the preceding step, the amount of each step becomes equal to the distance d between the measurement points so that the following expression (3) is established.
[0043] [Numeral 3]
[0000] D STEP =d (3)
[0044] Incidentally, when the detecting unit 200 is moved first stepwise (in the case of i=1), it is necessary to align the output of the detection portion 201 with the output of the detection portion 202 at the initial position. Accordingly, it is desirable that the scale 209 is an absolute scale but the scale 209 may be an incremental scale according to the position information detecting method.
[0045] Measurement error f (d·i) at the i-th step (i=0, 1, . . . , n) can be expressed as the following expression (4) in accordance with the aforementioned expressions (1) and (3).
[0046] [Numeral 4]
[0000] f ( d·i )= m 1 ( d·i )− d·i (4)
[0047] In the aforementioned expression (4), measurement error is calculated based on the output of the detection portion 201 while the sampling position is used as a measurement reference. When the output of the detection portion 201 is acquired and the aforementioned expression (4) is calculated based on the output after each step is completed, measurement error f (d·i) on the whole length of the scale 209 can be obtained and a self-calibration curve based on the measurement error f(d·i) can be obtained.
[0048] Although improvement in accuracy of the encoder can be attained when this self-calibration curve is used for correcting graduations of the scale 209 , it is impossible to calibrate measurement error of higher-frequency highly accurate graduations by the configuration of the aforementioned basic principle because reduction in the distance d between measurement points is limited. Accordingly, the displacement detecting device according to this embodiment uses the detecting unit 20 having at least three detection portions for performing self-calibration as follows.
[0049] FIG. 4 is a view for explaining the configuration of the detecting unit in the photoelectric encoder. FIG. 5 is a view for explaining steps in the detecting unit. Although the detecting unit 20 shown in FIG. 1 is formed to have the first to third detection portions 21 to 23 , the detecting unit 20 can be formed to have a larger number of detection portions. Accordingly, description will be made here on the assumption that the detecting unit 20 has n (n is an integer not smaller than 3 ) detection portions.
[0050] As shown in FIG. 4 , the detecting unit 20 has n detection portions, that is, first to n-th detection portions 21 to n. The distances between measurement points of the respective detection portions are set as d, α 2 d, α 3 d, . . . , a n−1 d in view from the first detection portion 21 to the n-th detection portion. α i is a non-integer constant larger than 1 and is calculated in advance.
[0051] First, output data at measurement points of the respective detection portions 21 to n at an initial position are acquired. Then, output data at measurement points in the first step are acquired in such a manner that the detecting unit 20 is moved stepwise in the scanning direction X while the amount of each step is controlled based on the output data acquired at the initial position so that, for example, the output at the measurement point of the first detection portion 21 at the first step is aligned with the output at the measurement point of the second detection portion 22 at the initial position.
[0052] Then, output data at measurement points in the second step are acquired in such a manner that the detecting unit 20 is moved stepwise likewise while the amount of each step is controlled based on the output data acquired at the first step so that, for example, the output at the measurement point of the first detection portion 21 at the second step is aligned with the output at the measurement point of the second detection portion 22 at the first step.
[0053] Output data at measurement points in the third step are further acquired in such a manner that the detecting unit 20 is moved stepwise likewise while the amount of each step is controlled based on the output data acquired at the initial position so that, for example, the output at the measurement point of the first detection portion 21 at the third step is aligned with the output at the measurement point of the third detection portion 23 at the initial position.
[0054] When the detecting unit 20 is moved stepwise while the amount of each step is controlled based on the output data acquired at the measurement points of the second to n-th detection portions 22 to n in accordance with each step so that, for example, the output at the measurement point of the first detection portion 21 is aligned with those at the measurement points of the second to n-th detection portions 22 to n in this manner, a region in which the sampling interval is shorter than the distance d (e.g. the interval (α 2 −1)·d<d) appears.
[0055] Moreover, when the aforementioned step is repeated on the whole length of the scale, a sampling interval shorter than the distance d can be obtained at random. Therefore, though configuration is made so that the distances between measurement points of the respective detection portions 21 to n are all not shorter than d, measurement error can be calculated at a sampling interval not longer than d and a self-calibration curve can be obtained to correct position information of the scale.
[0056] Although measurement references for calculating measurement error are sampling positions, all the sampling positions can be calculated back based on the known measurement point distances d to α n−1 d. In this manner, the displacement detecting device according to this embodiment can be formed without any expensive configuration so that measurement error of graduations can be calibrated easily, inexpensively and accurately.
[0057] The aforementioned configuration will be described below specifically according to Example. FIG. 6 is a view for explaining operation based on simulation models of detecting units according to Example of the invention and Comparative Example. FIG. 7 is a view for explaining operation based on the simulation model of the detecting unit according to Example.
[0058] As shown in FIG. 6 , the detecting unit 20 according to Example has such three detection portions that the distance d between measurement points of the first detection portion 21 and the second detection portion 22 is set to be 10 mm and the distance α 2 d between measurement points of the second detection portion 22 and the third detection portion 23 is set to be 12.5 mm.
[0059] On the other hand, the detecting unit 20 A according to Comparative Example has such two detection portions that the distance d between measurement points of the first detection portion 21 and the second detection portion 22 is set to be 10 mm. Accordingly, the detecting unit 20 is formed so that the aforementioned parameters satisfy n=3, d=1 and α 2 =1.25 whereas the detecting unit 20 A is formed so that the aforementioned parameters satisfy n=2 and d=1.
[0060] Obtained sampling positions are simulated on 100 mm in such a manner that each detecting unit 20 or 20 A is moved stepwise so that the output at the measurement point of the first detection portion 21 is aligned with the output at the measurement points of the second and third detection portions 22 and 23 . As a result, it is obvious that the sampling interval in the detecting unit 20 according to Example is 2.5 mm from the moving region after 60 mm whereas the sampling interval in the detecting unit 20 A according to Comparative Example is 10 mm on the whole region.
[0061] This indicates that the sampling interval in Example is one fourth as long as the sampling interval in Comparative Example. That is, this indicates that measurement error can be calculated at sampling intervals of 10 mm or shorter even if the distance between measurement points is 10 mm or longer. Accordingly, measurement error of graduations can be calibrated accurately compared with Comparative Example.
[0062] Incidentally, in the example shown in FIG. 6 , the sampling interval in Example is not always 2.5 mm in the moving region of 0 to 60 mm. Accordingly, it is obvious that higher accuracy can be further attained. It is therefore desirable that configuration is made in such a manner that the detecting unit 20 is reciprocated in the detection range of the scale 10 to add sampling positions as shown in FIG. 7 .
[0063] Specifically, sampling positions are obtained in a forward path in the aforementioned manner and sampling positions are added in a backward path in such a manner that the detecting unit 20 is moved stepwise so that, for example, the output at the measurement point of the third detection portion 23 is aligned with the outputs at the measurement points of the first and second detection portions 21 and 22 obtained in the forward path. In this manner, the sampling interval can be set to be 2.5 mm on the whole length in the detection range of the scale.
[0064] Although the embodiment of the invention has been described above, the invention is not limited thereto but various changes, additions, etc. may be made without departing from the gist of the invention. For example, the photoelectric encoder may be a linear type or a rotary type. As shown in FIG. 8 , at least three detection portions 21 , 22 and 23 of the detecting unit 20 may be made of one photo acceptance element array separated into at least three photo acceptance regions so that, for example, distances d to α n−1 d (d and α 2 d in FIG. 8 ) between measurement points are formed as described above. Further, the invention can be applied not only to an incremental scale having a periodic optical lattice but also to an absolute scale having a pseudo-random code pattern and a multi-track scale having both or either of these scales. | A displacement detecting device includes: a scale which has an optical lattice; a detecting unit which is disposed so as to be movable in a scanning direction relative to the scale, inclusive of at least a first detection portion, a second detection portion and a third detection portion, arranged in the scanning direction for detecting position information from the optical lattice; and a calculating portion configured to obtain a self-calibration curve on graduations of the scale by specifying positions of the detection portions and calculating measurement error based on the position information detected by the detecting unit, wherein: the detecting unit is provided so that a distance between the first detection portion and the second detection portion and a distance between the second detection portion and the third detection portion are different from each other and do not form an integral multiple. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to a method of fabricating a dielectric layer. More particularly, the present invention relates to a method of fabricating a carbon-rich low dielectric constant film.
[0003] 2. Description of Related Art
[0004] Due to the rapid increase in circuit integration and functional integration, multi-layered conductive line systems with low dielectric constant material layers separating them are required. Conventionally, silicon oxide is used as the material constituting the dielectric layer. However, as the number of layers increases, overall thickness increases proportionately. Thickness can be reduced if the dielectric layer is made from a material having a lower dielectric constant. In general, the lower the dielectric constant of a dielectric layer, the thinner the dielectric layer is required to be to isolate the two neighboring conductive layers. Therefore, carbon-rich dielectric film, which has a lower dielectric constant than a conventional silicon oxide layer, is now routinely used in the fabrication of integrated circuits. The carbon-rich dielectric film is also capable of minimizing the effect of resistance-capacitance (RC) delay in a semiconductor circuit due to a narrowing of line width. In general, the carbon-rich low dielectric constant film is formed by plasma-enhanced chemical vapor deposition (PECVD) using gases having different carbon contents.
[0005] [0005]FIG. 1 is a flow chart showing the steps for producing a carbon-rich low dielectric constant film using a conventional PECVD process. In the PECVD, oxygen and oxynitride plasma is used in the main deposition process. To prevent negatively charged particles in the plasma from depositing rapidly onto the dielectric film after plasma shut down, silicon-containing gases are first shut down after the main deposition process so that oxygen or oxynitride plasma can still hold the negatively charged particles up a little longer. After a purging period, the particle is sucked out of the reaction chamber by a pump. According to surface energy theory, surface energy can be represented by a simple formula 4πr 2 γ, where γ is the surface energy per unit area. For a plurality of smaller particles and one large particle having identical volume, the smaller particles have larger surface energy, resulting in rapid congregation, so that a smaller surface energy level is obtained. This explains why micro-particles within plasma congregate so rapidly.
[0006] Since negatively charged micro-particles may drop onto the low dielectric constant film and low dielectric constant film already has a lower density than a conventional silicate film, resistance against oxygen and oxynitride is rather low. Ultimately, the low dielectric constant film may lose its low dielectric constant property.
SUMMARY OF THE INVENTION
[0007] Accordingly, one object of the present invention is to provide a method of fabricating a low dielectric constant film that can prevent surface oxidation of the dielectric film from oxygen plasma.
[0008] To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a method of forming a low dielectric constant film. A silicon substrate is provided. A main deposition is carried out inside a reaction chamber to form a carbon-rich low dielectric constant film over the substrate. The carbon-rich low dielectric constant film is formed by performing plasma chemical vapor deposition using plasma such as oxynitride and nitrogen. After the formation of the dielectric film, the supply of oxynitride to the reaction chamber is cut off while ammonia is passed into the reaction chamber so that the micro-particles over the dielectric film are purged. By adjusting the flow rate of ammonia, as well as the pressure and the plasma density inside the plasma reaction chamber, different ammonia plasma conditions are produced. Different plasma conditions of the ammonia are applied in sequence to clear away micro-particles on the dielectric film.
[0009] In this invention, ammonia plasma is used instead of oxynitride and nitrogen plasma to carry out purging. The ammonia plasma can remove micro-particles from the surface of low dielectric constant film without causing any surface oxidation.
[0010] In addition, using different ammonia plasma conditions in the purging step prevents the rapid congregation of micro-particles within the plasma, in addition to keeping them from dropping onto the dielectric film. Hence, a quality carbon-rich low dielectric constant film is produced.
[0011] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
[0013] [0013]FIG. 1 is a flow chart showing the steps for producing a carbon-rich low dielectric constant film using a conventional PECVD process;
[0014] [0014]FIG. 2 is a flow chart showing the steps for producing a carbon-rich low dielectric constant film according to one preferred embodiment of this invention;
[0015] [0015]FIG. 3 is a table listing out the physical properties of dielectric film on nine silicon wafers fabricated using three different purging sequences according to this invention;
[0016] [0016]FIG. 4 a is a diagram showing particle diameter distribution within the low dielectric film after purging with plasma having first condition parameters; and
[0017] [0017]FIG. 4 b is a diagram showing particle diameter distribution on the low dielectric film after purging with plasma having first condition parameters.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
[0019] [0019]FIG. 2 is a flow chart showing the steps for producing a carbon-rich low dielectric constant film according to one preferred embodiment of this invention. The major aspect of this invention is the purging of micro-particles from a dielectric film after a main deposition process inside a plasma reaction chamber. A step-wise adjustment of the ammonia plasma parameter is carried out so that all micro-particles are effectively removed. The following is a detailed description of the ammonia plasma parameters used in the purging process.
[0020] First, a silicon substrate is provided. A main deposition is carried out inside a plasma reaction chamber using oxynitride and nitrogen plasma to form a carbon-rich low dielectric constant film having a thickness of about 3000 Å over the substrate. Reactive gases for carrying out the main deposition include, for example, tetra methyl silicate compound and oxygen-containing oxidized gases. The main deposition step is carried out inside a plasma reaction chamber at a temperature of about 400° C., a flow rate of gaseous tetra-methyl silicate compound of about 1000 sccm, a flow rate of gaseous oxynitride of about 7000 sccm, a flow rate of gaseous nitrogen of about 1000 sccm, a pressure of about 2.8 torrs and a plasma density of about 0.8 W/cm 2 .
[0021] In the main deposition step, since the plasma includes gaseous oxynitride, the flow of oxynitride into the reaction chamber needs to be stopped during the purging process so that the oxidation of the carbon-rich low dielectric constant film is prevented. On the other hand, the flow of gaseous nitrogen is maintained. Moreover, ammonia is also passed into the reaction chamber so that ammonia plasma can purge any remaining micro-particles after the main deposition step.
[0022] Ammonia plasma is generated inside the reaction chamber after the main deposition step. Parameters that control the properties of the ammonia plasma are adjusted so that the ammonia plasma is maintained in various conditions in sequence. In the first stage, plasma density is first reduced to about 0.5˜0.7 W/cm 2 and the flow of oxynitride into the reaction chamber is shut down. Gaseous ammonia having a flow rate of about 3000 sccm, roughly 40% to 60% of the former flow rate of gaseous oxynitride, is permitted to flow into the reaction chamber. Pressure inside the reaction chamber is also lowered to about 2.0 torrs, roughly 60% to 80% of the pressure inside the reaction chamber during main deposition. Micro-particles are purged under the aforementioned first stage purging conditions for about 1 to 5 seconds.
[0023] In the second stage, plasma density inside the reaction chamber is reduced to about 0.3 to 0.5 W/cm 2 . The flow rate of gaseous ammonia is adjusted to 2000 sccm, roughly 20% to 40% of the flow rate of gaseous oxynitride during main deposition. Pressure inside the reaction chamber is also reduced to about 1.0 torr, roughly 30% to 50% of the pressure inside the reaction chamber during main deposition. Micro-particles are purged under the aforementioned second stage purging conditions for about 1 to 5 seconds.
[0024] In the third stage, plasma density inside the reaction chamber is reduced to a value below 0.3 W/cm 2 . The flow rate of gaseous ammonia is further adjusted to 1000 sccm, roughly 5% to 20% of the flow rate of gaseous oxynitride during main deposition. The gaseous nitrogen supply into the reaction chamber is completely shut off. Pressure inside the reaction chamber is further reduced to about 0.5 torr. Micro-particles are purged under the aforementioned third stage purging conditions for about 1 to 5 seconds.
[0025] In the fourth or last stage, plasma density and ammonia supply are reduced to zero. Pressure inside the reaction chamber is pumped to the lowest pressure, thereby ending the micro-particle purging process. Note that the various plasma parameters such as plasma density, flow rates of various gases, reaction chamber pressure and purging intervals may be separately adjusted according to processing requirements.
[0026] However, each parameter, including plasma type, plasma density, reaction chamber pressure and the flow rate of various gases, contributes to the effectiveness of micro-particle purging. In the following, three different plasma parameter settings are used to carry out micro-particle purging. For each plasma parameter setting, a carbon-rich low dielectric constant film having slightly different physical properties is produced.
[0027] First, a main deposition is carried out to form a carbon-rich low dielectric constant film. The main deposition is conducted, for example, at a temperature of about 400° C., a gaseous tetra-methyl silicate flow rate of about 1000 sccm, a gaseous oxynitride flow rate of about 7000 sccm, a gaseous nitrogen flow rate of about 1000 sccm, a reaction chamber pressure of about 2.8 torr and a plasma density of about 0.8 W/cm 2 .
[0028] After the main deposition step, the following three plasma condition settings are employed to purge the micro-particles from the carbon-rich low dielectric constant film.
[0029] In the first purging sequence, the supply of gaseous oxynitride and gaseous nitrogen plasma is continued. The supply of silicon-containing tetra-methyl silicate is terminated while plasma density is reduced to zero. Micro-particle purging using oxynitride and nitrogen plasma is conducted for about 10 seconds.
[0030] In the second purging sequence, the supply of gaseous oxynitride and gaseous nitrogen plasma is continued. The supply of silicon-containing tetra-methyl silicate is terminated. Plasma density is adjusted to about 0.6 W/cm 2 and the flow rate of oxynitride is reduced to about 3500 sccm. Pressure inside the reaction chamber is reduced to about 2.0 torrs. A first micro-particle purging is conducted under such conditions for about 2 seconds. Thereafter, the plasma density is reduced to about 0.4 W/cm 2 , the flow rate of gaseous oxynitride is reduced to about 2000 sccm and the reaction chamber pressure is set to about 1.0 torr. A second micro-particle purging is conducted under such conditions for about 2 seconds. Subsequently, the plasma density is further reduced to about 0.2 W/cm2, the flow rate of oxynitride is reduced to 1000 sccm and the pressure inside the reaction chamber is further reduced to a value below 0.5 torr. A third micro-particle purging is conducted under such conditions for about 2 seconds. Finally, all gaseous supply is shut, the plasma density is reduced to zero and pressure inside the reaction chamber is reduced to a minimum value by a vacuum pump.
[0031] In the third purging sequence, the supply of gaseous oxynitride and gaseous nitrogen plasma is continued. The supply of silicon-containing tetra-methyl silicate is terminated. Plasma density is adjusted to about 0.6 W/cm 2 and the flow rate of oxynitride is reduced to zero. The flow rate of gaseous ammonia into the reaction chamber is set to about 3500 sccm. Pressure inside the reaction chamber is set to about 2.0 torrs. A first micro-particle purging is conducted under such conditions for about 2 seconds. Thereafter, the plasma density is reduced to about 0.4 W/cm 2 , the flow rate of gaseous ammonia is reduced to about 2000 sccm and the reaction chamber pressure is set to about 1.0 torr. A second micro-particle purging is conducted under such conditions for about 2 seconds. Subsequently, the plasma density is further reduced to about 0.2 W/cm2, the flow rate of ammonia is reduced to 1000 sccm and the pressure inside the reaction chamber is further reduced to a value below 0.5 torr. A third micro-particle purging is conducted under such conditions for about 2 seconds. Finally, all gaseous supply is shut, the plasma density is reduced to zero and pressure inside the reaction chamber is reduced to a minimum value by a vacuum pump.
[0032] [0032]FIG. 3 is a table listing out the physical properties of dielectric film on nine silicon wafers fabricated using three different purging sequences according to this invention. As shown in FIG. 3, for the silicon wafers numbered 1 ˜ 3 , the dielectric film has gone through a micro-particle purging operation using the first purging sequence. For the silicon wafers numbered 4 ˜ 6 , the dielectric film has gone through a micro-particle purging operation using the second purging sequence. Similarly, for the silicon wafers numbered 7 ˜ 9 , the dielectric film has gone through a micro-particle purging operation using the third purging sequence.
[0033] [0033]FIG. 4 a is a diagram showing particle diameter distribution within the low dielectric film after purging with plasma having first condition parameters. FIG. 4 b is a diagram showing particle diameter distribution on the low dielectric film after purging with plasma having first condition parameters. Elemental analysis of the graphs in FIGS. 4 a and 4 b reflect similar particle diameter distribution. This indicates that the micro-particles on the dielectric film are grown out of the plasma. Most microparticles have a diameter between 0.2 to 0.3 μm and most of them are congregations of small rounded particles. The distribution of micro-particle diameters and constructs is shown in FIG. 4 b.
[0034] The number of micro-particles on a low dielectric constant film is under 30 when the second or the third purging sequence is used. The main reason is that the oxynitride plasma in the second purging sequence and the ammonia plasma in the third purging sequence serve to suspend micro-particles in the plasma. By lowering the pressure inside the reaction chamber, the plasma density, the gas flow rates, and pumping the plasma out of the reaction chamber, the probability of micro-particles dropping onto the silicon wafer is lowered considerably. Although purging sequences two and three both manage to control the number of micro-particles to fewer than 30, the oxygen-containing oxynitride plasma in the second purging sequence may damage the low dielectric constant film. Consequently, the carbon content of a superficial layer of the dielectric film having a thickness between 300 Å to 400 Å may drop, as shown in FIG. 3. A drop in carbon content in a superficial layer of the dielectric film may lead to a change in physical properties. Ultimately, the dielectric constant of the low dielectric constant film is increased and subsequent etching is rendered more difficult.
[0035] As shown in FIG. 3, the third purging sequence provides the cleanest micro-particle removal. Purging using ammonia not only prevents the oxidation of the low dielectric constant film, but also limits the amount of drop in carbon content within the film. In addition, quantity of micro-particles on the low dielectric constant film is contained.
[0036] In conclusion, one major aspect of this invention is the replacement of oxygen or oxynitride plasma by ammonia plasma so that plasma oxidation of low dielectric constant film is prevented. Another advantage of using ammonia plasma is that the low dielectric constant film can have a uniform carbon content instead of being segregated into carbon-rich and carbon-poor layers. One further advantage of using ammonia to perform micro-particle purging is that the ammonia can force the micro-particles into suspension inside the plasma. Hence, with a corresponding lowering of the reaction chamber pressure, and the plasma density and gas flow rates, the number of micro-particles remaining on the low dielectric constant layer is minimal.
[0037] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents. | A method of forming a low dielectric constant film. The low dielectric constant film is formed by passing gaseous silicate into a reaction chamber and performing a plasma chemical vapor deposition to form a carbon-rich layer. Micro-particles deposited on the dielectric film are purged by ammonia. By adjusting the flow rate of ammonia, and the pressure and plasma density inside the reaction chamber, several ammonium plasma conditions are produced in sequence to clear the particles on the dielectric film. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to a microwave phase shifter which is capable, in response to a control signal, of generating a phase shift that is either substantially equal to zero or substantially equal to π.
2. Description of the Prior Art
The use of 0/π phase shifters is known, for example in devices for modulation by 0/π phase encoding or in the quantified electronic phase shifters used for each module of an electronic scanning radar antenna.
Several sorts of devices enabling the making of 0/π phase shifters, either for a phase modulator or as an elementary bit in an electronic phase shifter for scanning antenna, has been proposed to date. Among these are:
Phase shifters using a PIN diode placed at the end of a normally open transmission line. The PIN diode has the role of short-circuiting this line, in thus creating a phase shift variation equal to π. This phase shifter necessarily uses a circulator at the end of the line, and a circulator such as this is rather bulky. Furthermore, this type of phase shifter has limited performance characteristics, especially because of the stray capacitance of the diode which has a detrimental effect on its bandwidth.
Phase shifters using two PIN diodes placed at the end of the output arms of a 3 dB hybrid coupler. This hybrid coupler itself is also too bulky, so that this device has the same drawbacks as the previous one.
Interference phase shifters formed by the cascade mounting of cells with low phase shift, using pairs of PIN diodes to load a transmission line. These are devices that are alternately switched over from a type of high-pass filter to a type of low-pass filter, by modification of the state of the diodes. This type of phase shifter may be very bulky if it is desired that it should work in wideband mode, because its bandwidth can be increased only by correlatively increasing the number of cells.
Line switching phase shifters wherein two pairs of PIN diodes placed in T junctions enable the wave to go into either channel of the system, the difference in length between channels being equal to a half wavelength at the working frequency. This type of phase shifter too has the drawback of being bulky and of having a restricted bandwidth.
Inversion phase shifters as described in the document FR--A--2.379.196 wherein a transmission line, of the microstrip type for example, is coupled to a slot line by means of two PIN diodes with opposite states of operation. Depending on the state of the diodes, there follows an excitation of the slot line with phases having a difference intrinsically equal to π. This device has the drawback of being restricted, in terms of value of the bandwidth, to about 30% of the carrier frequency. Moreover, it practically cannot be made in integrated circuit form and is finally quite bulky.
SUMMARY OF THE INVENTION
The invention seeks to overcome these drawbacks. To this effect, it pertains to a 0/π phase shifter comprising at least one field effect transistor, to the gate of which the input microwave is applied, the output microwave being taken at the drain or at the source of this transistor. This phase shifter is fitted out with low-frequency switching-over means for the application, between the source and the drain, of a dc bias voltage with a determined value but with a sign differing according to the value of the phase shift (either zero or π) desired.
Advantageously, the source and the drain of the field effect transistor are each supplied through an electronic switch with low-frequency switching-over transistors which are capable of working under the same dc voltage as the field effect transistor.
BRIEF DESCRIPTION OF THE DRAWINGS
In any case, the invention will be clearly understood and its advantages and features will emerge in the course of the following description of a non-restrictive exemplary embodiment, made with reference to the appended drawings, of which:
FIG. 1 is a schematic drawing of this 0/π microwave phase shifter; and
FIG. 2 is a more detailed electrical diagram of this same microwave phase shifter.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, the reference 1 designates a gallium arsenide field effect transistor (or FET). This FET is advantageously chosen to be of the N type, the mobility of the electrons being greater than that of the holes. Furthermore, it is advantageously chosen to be practically symmetrical. A FET transistor such as this, owing to the symmetry that it shows between its drain and its source, has the property of having its structure turned upside down if voltages applied to these two electrodes are inverted, the electrode 2, which is initially the drain, becoming the source, and the electrode 3, which is initially the source, becoming the drain. It follows that, if the FET 1 is mounted as a microwave amplifier, the signal of one microwave output terminal 5 placed on one of the electrodes, in this case on the electrode 2, changes its sign during the above-mentioned reversal of the biases. This amounts to a phase shift by π of the output signal at 5 with respect to the input microwave signal applied at 6 to the gate 4 of the FET 1.
In the very basic circuit of FIG. 1, the negative dc bias of the grid 4 is applied to the terminal 7 through a microwave filter consisting of a choke 8 and a decoupling capacitor 9. The electrode 2 receives its bias at the terminal 10, through another microwave filter consisting of a choke 11 and a decoupling capacitor 62. The electrode 3, for its part, receives its bias at the terminal 12 through the dc bias resistance 13 which is decoupled by a capacitor 14. Just as in the previous case, this bias is applied through a filter consisting of a bias capacitor 15 and a choke 16. Furthermore, the load impedance of the load circuit is shown at 17.
In accordance with the invention, switching-over means, illustrated schematically by a bipolar inverter 18, make it possible, depending on the position of this inverter, either to apply the supply dc voltage +V to the terminal 10 and the ground to the terminal 12, or conversely to apply the ground to the terminal 10 and the dc voltage +V to the terminal 12. Since the FET is symmetrical, this reversal of the biases between source and drain leads to a reversal in the direction of the current in the semiconductor forming the channel of this transistor so that, as explained above, the microwave signal taken at the output 5 is phase-shifted by π. This circuit therefore gives the 0/π phase shift without using microwave switching-over elements, but simply dc voltage switching-over means which are low-frequency switching-over means.
A more practical scheme for achieving the basic circuit of FIG. 1 is shown, by way of an example, in FIG. 2.
This diagram shows the FET 1 with its electrode 3, its gate 4 and its other electrode 2.
The gate 4 is supplied in dc bias from the above-mentioned terminal 7, and through a standard gate bias circuit 19 comprising a choke and a decoupling capacitor (not shown).
The microwave signal is applied through the above-mentioned input terminal 7 to the gate 4, through an input matching circuit 20 comprising a connecting capacitor 21, a parallel inductive element 22 connected between the output 23 of the bias circuit 19 and the ground, with a blocking capacitor 25 for the dc current, and a series inductive element 24 connected between the point 23 and the point 4.
Moreover, advantageously, there is provided a parallel amplitude compensation circuit 26 on the gate 4. This circuit 26 consists of a resistor 27 in series with a decoupling capacitor 28. Its purpose is to make the gains or losses of the phase shifter, in both states, close to each other, and to improve the input standing wave ratio (SWR) of the phase shifter.
A series negative feedback circuit 29, comprising a capacitor 30 and a resistor 31 in series, is inserted between the electrode 2 and the gate 4. Its purpose is to stabilize the FET and to make the phase difference between the two states constant in a frequency band of at least one octave in S band, in taking a capacitance of the order of one picofarad. This series negative feedback further enables the gains or losses of the phase shifter to be brought close to each other in both states, and to improve its input standing wave ratio.
Furthermore, there is provision for a phase compensation circuit 32, consisting of a capacitor 33, parallel connected between the electrode 3 and the ground, and a parallel choke 34 with a decoupling capacitor 35 on the electrode 2, as well as an output matching circuit 36. This circuit 36 has two series-mounted chokes 37, 38, the junction point 39 of which is decoupled with respect to the ground by a capacitor 40, and it includes a connecting capacitor 41, the output microwave signal being taken at the above-mentioned terminal 5.
The above-mentioned switching-over means, capable of applying either the +V volts bias to the drain 2 and the 0 volts bias to the source 3 or, conversely, this same +V volts bias to the source 3 and the 0 volts bias to the drain 2, comprise four identical, relatively low-frequency switching-over NPN transistors 42, 43, 44, 45 which bias the electrodes 2 and 3, each by means of a choke and a microwave decoupling capacitor, respectively 46, 47 and 48, 49.
The two transistors 43, 42 each have their collector connected to the dc supply source +V which is, for example, of the order of 5 to 6 volts and is, consequently, as capable of supplying the switching-over transistors 42 to 45 as the FET 1. Their emitters are respectively connected to the electrodes 2 and 3 by means of the above-mentioned microwave filters 46, 47 and 48, 49.
To their respective base electrodes 50, 51, there is applied a 0 volts or +V volts control dc voltage which is provided by standard logic switching-over means that are not shown (consisting, for example, of the two outputs of an astable circuit working as a divider by two), in reverse to each of the respective bases 50, 51: when the 0 volts voltage is applied to the electrode 51, the +V voltage is simultaneously applied to the electrode 50 and vice versa.
The transistor 44 has its emitter connected to the ground while its collector is connected to the emitter of the transistor 43. Its base is supplied at 52 by the same control voltage, 0 volts or V volts, as the base 51 of the transistor 42. Similarly, the transistor 45 has its emitter connected to the ground while its collector is connected to the emitter of the transistor 42 and its base is supplied at 53 by the same control voltage, +V volts or 0 volts, as the base 50 of the transistor 43.
This circuit works as follows:
Let us assume, first of all, that the dc control voltages applied to the terminals 51, 52 on the one hand, and to the terminals 50, 53 on the other hand are respectively equal to +V volts and 0 volts as indicated in FIG. 2. It follows therefrom that the transistors 42 and 44 are saturated while the transistors 43 and 45 are off. The electrode 2 of the FET 1 is practically taken to the voltage +V volts while its source 3 is practically connected to the ground. The microwave signal applied at 6 is thus recovered at 5, normally amplified according to the gain of the transistor 1 which is normally equal to 1. If the control voltages are now inverted, the voltages at the terminals 51, 52 on the one hand and 50, 53 on the other hand are respectively equal to 0 volts and +V volts. Subsequently, the transistors 43 and 45 are saturated while the transistors 42 and 44 are off. This time, it is the electrode 3 that is practically taken to the dc supply voltage, +V volts, while the electrode 2 is practically connected to the ground. As explained above, the FET 1 is inverted so that the output microwave signal appearing at 5 is phase-shifted by π with respect to the preceding output signal.
Of course, the above-mentioned phase shift, obtained with the circuit of FIG. 2, is purely theoretical. For, it assumes that the FET used is perfectly symmetrical and it implies that the effects of the stray elements are totally compensated for, which is not always the case depending on the frequency used.
Tests show that, with a FET alone, chosen to be as symmetrical as possible, the difference in phase between the two states is very close to 180 degrees (insertion phase close to zero degrees for the phase shift 0 state and close to 180 degrees for the phase shift π state) for relatively low frequencies (below than 1 gigahertz), but that this difference becomes smaller when the frequency becomes higher, and does so all the more quickly as the area of the unit gate of the FET is great. For, the effects of the stray elements of the FET are increased with the frequency and with the area of the unit gate.
The phase compensation circuit 32 advantageously reduces the effects of the stray elements. The circuit of FIG. 2 is simple to implement, using one and the same supply voltage for the FET and the switching-over transistors 43 to 45, and comprising no microwave switching-over element. It enables a phase difference of 180 degrees ±2 degrees to be obtained on about 30% of the frequency band in S band.
It is also appropriate to point out that, unlike what happens with known phase shifters, with this new type of circuit, the losses may be made null for both states. For, if the FET is chosen so that this circuit, which is actually an amplifier circuit, has a gain that is strictly equal to 1, it follows that the losses of the phase-shifter are null for each of the two states 0 or π.
It goes without saying that the invention is not restricted to the exemplary embodiment that has just been described. Other compensation circuits could be added to those with which the device of FIG. 2 is already fitted out. Circuits comprising several FETs, working for example in parallel, could be used. The FET could possibly be not perfectly symmetrical, and could have its circuit adapted accordingly. Instead of being taken at the electrode 2 of the FET, the microwave output could be taken at the electrode 3. Instead of a supply voltage (+V, 0) taken between a single positive terminal and the ground, a supply source (+V, -V) comprising a first positive terminal and a second negative terminal could also be used. The material of which the field effect transistor is made could be other than gallium arsenide, and its doping could be of the P type instead of the N type, etc. | Disclosed is a microwave phase shifter which is capable, in response to a control signal, of generating either a phase shift that is substantially zero or a phase shift that is substantially equal to π. It comprises a FET that is preferably symmetrical and works in an amplifier assembly. Low-frequency switching-over means make it possible, by reversing the biases at the source and the drain, to invert the FET. This inverting causes a phase shift by π in the microwave signal taken at the output of the circuit. | 7 |
BACKGROUND
Common in the downhole drilling and completion arts is the traditional body lock ring. The ring is well known and includes a finely threaded section commonly referred to as “wicker threads” or “wickers” on an inside dimension of the body lock ring that are configured to be engageable with a set of wickers on an outside dimension surface of another component. The body lock ring may be urged along the other component under an applied force to ratchet into a final set position. Because there is a finite distance between adjacent peaks of wicker threads, there is necessarily a potential backlash. In the event that the applied force brings the wickers to very close but not quite the next wicker trough, the device being actuated will relax in backlash by the distance between the wickers. It is possible to reduce backlash by reducing the peak-to-peak distance between adjacent wickers. A reduction in this dimension, however, is often accompanied by a reduction in every tooth dimension including height and flank surface area as well. A reduction in tooth flank surface area tends to proportionally reduce the “holding ability” of such flanks. While the backlash is necessarily reduced in this type of construction, the potential for slippage of the body lock so constructed is increased. Since slippage is unquestionably undesirable, wickers with reduced peak-to-peak dimensions are not often the selected solution to the backlash problem.
In some situations the backlash is inconsequential while in others it can be catastrophic to the function of the particular tool or device. For example, if the device is a sealing tool, the backlash may allow sufficient energy in the seal to relax that the seal function is substantially lost. In other devices, while the entire or any substantial part of the functionality may not be lost, it clearly would be better for the ring to retain the input energy than to lose energy. Hence, it is axiomatic that the art would well receive improved apparatus where backlash is reduced or eliminated.
SUMMARY
A zero backlash downhole setting tool including a mandrel having a number of recesses therein; a subassembly having a number of fingers at least partially receivable in the recesses, the subassembly in force transmissive communication with a device to be set; a lock wedge in radially deflecting communication with the fingers; and a setting sleeve in operable communication with the device to be set and the lock wedge.
A method for setting a device with zero backlash including running the zero backlash downhole setting tool including a mandrel having a number of recesses therein; a subassembly having a number of fingers at least partially receivable in the recesses, the subassembly in force transmissive communication with a device to be set; a lock wedge in radially deflecting communication with the fingers; and a setting sleeve in operable communication with the device to be set and the lock wedge into a borehole with a device to be set; urging a setting sleeve in a direction to set the device; moving a lock wedge with the setting sleeve into contact with the fingers; and deflecting the fingers into the recesses.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings wherein like elements are numbered alike in the several Figures:
FIG. 1 is a schematic cross sectional view of a zero backlash downhole setting tool in an unset position;
FIG. 2 is a perspective view of the fingers illustrated and identified in FIG. 1 ;
FIG. 3 is a perspective view of a mandrel upon which other components of the downhole setting tool mount, and that is configured to receive the fingers illustrated in FIG. 2 ;
FIG. 4 is an illustration similar to that of FIG. 1 but somewhat magnified and in the set position; and
FIG. 5 illustrates alternate surface treatments for the fingers illustrated in FIG. 2 .
DETAILED DESCRIPTION
Referring to FIG. 1 , a zero backlash downhole setting tool 10 includes a mandrel 12 having a number of recesses 14 therein. The recesses are illustrated in the Figures hereof as four in number but it is to be understood that other numbers of recesses 14 are also employable. Each recess 14 includes two ends 16 and 18 (see also FIG. 3 ). Ends 16 are larger cross sectionally than ends 18 . More specifically, and addressing the shape actually illustrated (but recognizing that the specific shape is not intended to be construed as limiting), the cross section of end 16 is in the shape of a trapezoid. End 18 is also in the shape of a trapezoid but the area defined by the trapezoid at 16 is greater than the area defined by the trapezoid at 18 . In one embodiment each side of trapezoids at end 16 are larger than each side of the trapezoids at end 18 .
Mounted at the mandrel 12 and still referring to FIG. 1 , is a device 20 (such as a seal or any other axial force settable tool) to be set by the downhole setting tool 10 . As illustrated the device 20 is a seal but it is to be understood that any device requiring axial compression for setting can be set by the downhole setting tool 10 . As illustrated the device 20 is integral with a plurality of fingers 22 . The fingers are deflectable radially inwardly at least partially into recesses 14 during use of the downhole setting tool 10 . Facilitating flexibility of the fingers 22 in the illustrated embodiment is a flexibility groove 24 extending from an inside dimension surface 26 toward an outside surface 26 without reaching the outside surface 26 creating a living hinge 28 . In an alternate embodiment that would illustrate the same as the FIG. 1 embodiment can be configured with the fingers 22 supported not by the device 20 but by their own ring 25 that will be adjacent the position the living hinge 28 occupies in device 20 (see FIG. 2 ). Such embodiment will be distinct from device 20 at line 27 . The alternate subassembly 29 of the fingers will other than in FIG. 2 appear similar to that illustrated since that subassembly will be directly adjacent the device 20 .
Still referring to FIG. 1 , one or more resilient elements 30 are positioned to be axially compressively loadable during use of the downhole setting tool 10 . In one embodiment the resilient elements are a series of spring washers. As illustrated, the spring washers are frustoconical washers. Adjacent the fingers 22 is a lock wedge 32 having a frustoconical inside surface 33 that is moveable into contact with the fingers to maintain a particular selected position of the fingers during use of the device. The surface has an angle alpha of greater than about 0 degrees and about 45 degrees to facilitate self locking of the frustoconical surface with the fingers. In a specific embodiment the angle is about 7 degrees. The angle alpha appropriately selected in accordance herewith can be determined using the formula:
alpha=arctan(coefficient of friction)
The embodiment of FIG. 2 illustrates a smooth surface having, accordingly, a relatively low coefficient of friction. In other embodiments, two illustrated in FIG. 5 at numeral 35 and 37 , a surface having a greater coefficient of friction is presented enabling different angles. Numeral 37 indicates a wickered (toothed profile) surface that will bite into the frustoconical surface 33 of the lock wedge 32 . It should be noted that the surface 33 can be textured similarly, if desired. Further it is noted that each of the fingers 22 may have the same surface texture or may have different surface textures, as desired.
The downhole setting tool 10 further includes a setting sleeve 34 having an inside diameter surface 36 that is large enough to extend over an outside dimension of the lock wedge 32 .
In operation, a setting force is applied from somewhere to the left of the drawing in FIG. 1 on setting sleeve 34 . The setting force may be from a surface location or other remote location. Upon initial axial load, the force is transmitted to the one or more resilient elements and through those to the device 20 . The one or more resilient elements are to be selectively compressed by the action of the setting sleeve 34 primarily so that a significant amount of biasing force remains available in the system post setting. It will be appreciated that the setting sleeve 34 inside dimension surface 36 extends axially farther than the lock wedge does leaving an annular volume 38 . The volume 38 functions to ensure that the one or more resilient elements 30 are selectively compressed while the setting sleeve 34 is being set and before making contact with the lock wedge 32 . Once the one or more elements 30 are compressed to the selected degree, the degree being related to substantial set of the device 20 , setting sleeve 34 closes the volume 38 and causes a contact between sleeve shoulder 40 and lock wedge end 42 . Because the one or more resilient members are not fully compressed prior to or even at the contact between sleeve shoulder 40 and lock wedge 42 , there is still the possibility of relative movement between the setting sleeve 34 and the finger 22 , which relative movement is needed to allow the lock 32 to move toward the device 20 and deflect the finger(s) 22 radially inwardly into contact with the recesses 14 .
It is to be understood that the finger(s) 22 deflect at the living hinge 28 and hence do not directly radially inwardly move as a unit but rather tips 44 of the fingers 22 will move more radially inwardly than bases 46 , see FIG. 2 .
The set position of the downhole setting tool 10 is illustrated in FIG. 4 where the position of the tips 44 of the fingers 22 are shown more deeply received in the recess 14 than the bases 46 of the fingers 22 . At this point the particular shape of the recesses 14 and the particular shape of the fingers 22 will be better understood. Because of the trapezoidal shape, or other shapes having similar functionality as conveyed hereunder, walls 48 the fingers 22 will have contact with walls 50 of the recesses 14 no matter what relative axial position the fingers and recesses have. The further the tips 44 are from end 18 the deeper into the recesses 14 the tips 44 will go before wall-to-wall contact is achieved. The closer the tips 44 are to the end 18 of the recesses 14 the shallower the radially movement of the tips 44 needs to be before achieving wall-to-wall contact. Once wall to wall contact is achieved, and the lock wedge is jammed radially outwardly of the fingers 22 , the system cannot move and hence the setting force put into the device 20 will be maintained indefinitely. The holding force supplied by the downhole setting tool 10 is frictional between the walls of the fingers and the walls of the recesses. Since there are no peaks such as wickers have, there is no backlash. The downhole setting tool 10 described has no backlash and in addition has the benefit of a compressed spring force acting to hold the device 20 in a set position.
While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation. | A zero backlash downhole setting tool includes a mandrel having a number of recesses therein. A subassembly having a number of fingers is at least partially receivable in the recesses. The subassembly is in force transmissive communication with a device to be set. A lock wedge is in radially deflecting communication with the fingers and a setting sleeve is in operable communication with the device to be set and the lock wedge. Also included is a method for setting a device with zero backlash. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Korean Patent Application No. 10-2015-0011037 filed on Jan. 23, 2015, and Korean Patent Application No. 10-2015-0187758 filed on Dec. 28, 2015 with the Korean Intellectual Property Office, the disclosures of which are herein incorporated by reference in their entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to a superabsorbent polymer, in which a surface crosslinking layer crosslinked by surface-modified inorganic particles is introduced, and therefore, centrifuge retention capacity (CRC), absorbency under pressure (AUP), and permeability are improved at the same time, and a preparation method thereof.
BACKGROUND ART
[0003] A super absorbent polymer (SAP) is a synthetic polymeric material capable of absorbing moisture in about 500 to 1000 times its own weight. Various manufacturers have been denominated it as different names such as SAM (Super Absorbency Material), AGM (Absorbent Gel Material) or the like. Since such superabsorbent polymers started to be practically applied in sanitary products, now they have been widely used not only for hygiene products such as disposable diapers for children, sanitary napkins etc., but also for water retaining soil products for gardening, water stop materials for the civil engineering and construction, sheets for raising seedling, fresh-keeping agents for food distribution fields, materials for poultice or the like.
[0004] In many cases, such superabsorbent polymers are widely used in hygiene products such as diapers, sanitary napkins etc. For this purpose, superabsorbent polymers are required to have high water absorption, must not release absorbed water even under an external pressure, and also must maintain the shape under volume expansion (swelling) due to water absorption to show excellent permeability.
[0005] Reportedly, it is difficult to improve centrifuge retention capacity (CRC), which is a basic physical property of showing water absorption and retention capacities, and absorbency under pressure (AUP), which is a property of retaining absorbed water even under an external pressure, at the same time. The reason is that when the overall crosslinking density of the superabsorbent polymer is controlled to be low, centrifuge retention capacity becomes relatively high, but a crosslinking structure becomes loose and gel strength becomes low, leading to a reduction in absorbency under pressure. On the contrary, when the crosslinking density is controlled to be high, and therefore absorbency under pressure is improved, water is hardly absorbed between compact crosslinking structures, leading to a reduction in basic centrifuge retention capacity. Because of the above-described reasons, there have been limitations in the preparation of superabsorbent polymers having both improved centrifuge retention capacity and absorbency under pressure.
[0006] Meanwhile, when superabsorbent polymers are exposed to high humidity, superabsorbent polymers absorb water in air and agglomerate together into a large mass, that is, a caking phenomenon occurs. To prevent this caking phenomenon, superabsorbent polymers are mixed with an inorganic additive such as silica.
[0007] However, effective dispersion of the inorganic additive in the superabsorbent polymer is difficult, and therefore, the effect of the inorganic additive is unsatisfactory. Further, because of physical blending of the inorganic additive with the superabsorbent polymer, the inorganic additive breaks away therefrom to cause problems of dust generation and changes in physical properties.
DISCLOSURE
Technical Problem
[0008] Accordingly, the present invention is intended to provide a superabsorbent polymer, of which surface is crosslinked by surface-modified inorganic particles, thereby having excellent physical properties of showing improved centrifuge retention capacity (CRC), absorbency under pressure (AUP), and permeability at the same time.
[0009] Further, the present invention is intended to provide a method of preparing the superabsorbent polymer.
Technical Solution
[0010] The present disclosure provides a superabsorbent polymer including a base polymer powder including a crosslinked polymer resulting from polymerization of water-soluble ethylene-based unsaturated monomers having acidic groups which are at least partially neutralized, in the presence of an internal crosslinking agent; and a surface crosslinking layer formed on the base polymer by additionally crosslinking the crosslinked polymer in the presence of surface-modified inorganic particles, in which inorganic particles chemically bind to the crosslinked polymer included in the surface crosslinking layer via an oxygen-containing bond or a nitrogen-containing bond.
[0011] Further, the present invention provides a method of preparing the superabsorbent polymer, the method including the steps of: performing crosslinking polymerization of water-soluble ethylene-based unsaturated monomers having acidic groups which are at least partially neutralized, in the presence of an internal crosslinking agent to form a hydrogel polymer; drying, pulverizing, and classifying the hydrogel polymer to form the base polymer powder; and additionally crosslinking the surface of the base polymer powder in the presence of inorganic particles which are surface-modified with one or more functional groups selected from the group consisting of an epoxy group, a hydroxy group, an isocyanate group, and an amine group to form the surface crosslinking layer.
[0012] Hereinafter, the superabsorbent polymer and the preparation method thereof will be described in more detail according to specific embodiments of the present invention. However, these are for illustrative purposes only, and the scope of the present invention is not intended to be limited thereby. It will be apparent to those skilled in the art that various modifications may be made thereto without departing from the scope of the invention.
[0013] Additionally, the term “including” or “containing” means that it includes a particular component (or particular element) without particular limitations unless otherwise mentioned in the present entire disclosure, and it cannot be interpreted as it excludes the addition of the other components.
[0014] According to an embodiment of the present invention, provided is the superabsorbent polymer including the base polymer powder including the crosslinked polymer resulting from polymerization of water-soluble ethylene-based unsaturated monomers having acidic groups which are at least partially neutralized, in the presence of an internal crosslinking agent; and the surface crosslinking layer formed on the base polymer by additionally crosslinking the crosslinked polymer in the presence of surface-modified inorganic particles, in which inorganic particles chemically bind to the crosslinked polymer included in the surface crosslinking layer via an oxygen-containing bond or a nitrogen-containing bond.
[0015] The experimental results of the present inventors demonstrated that when the surface crosslinking layer is formed by additionally crosslinking the surface of the base polymer powder in the presence of inorganic particles surface-modified with one or more functional groups selected from the group consisting of an epoxy group, a hydroxy group, an isocyanate group, and an amine group, the inorganic particles chemically bind to the crosslinked polymer included in the surface crosslinking layer, and therefore, breakaway of the inorganic particles from the superabsorbent polymer may be prevented during preparation and transportation of the superabsorbent polymer, and the superabsorbent polymer may have improved absorbency under pressure and permeability, thereby completing the present invention.
[0016] The superabsorbent polymer thus prepared includes, for example, the base polymer powder including the crosslinked polymer which is formed by crosslinking polymer chains of the water-soluble ethylene-based unsaturated monomers via a crosslinkable functional group of the internal crosslinking agent, and the surface crosslinking layer formed by additionally crosslinking the crosslinked polymers present on the surface of the base polymer powder with inorganic particles which are surface-modified by two or more crosslinkable functional groups per one particle.
[0017] Accordingly, the superabsorbent polymer of an embodiment has the surface crosslinking layer which is formed by crosslinking the crosslinked polymers present on the surface via surface-modified inorganic particles, and has a structure in which the crosslinked polymers in the surface crosslinking layer chemically bind with inorganic particles through an oxygen-containing bond or a nitrogen-containing bond derived from crosslinkable functional groups of the inorganic particles. More particularly, the crosslinked polymers in the surface crosslinking layer chemically bind with the inorganic particles through an oxygen-containing bond such as —O—, —COO—, etc. or a nitrogen-containing bond such as —CONR— or —NR— (R is hydrogen or an alkyl group having 1 to 3 carbon atoms).
[0018] Owing to the surface crosslinking structure including the inorganic particles, agglomeration between particles hardly occurs, thereby effectively preventing a caking phenomenon in the superabsorbent polymer of an embodiment, that is, agglomeration of particles into a large mass due to absorption of water in air by the superabsorbent polymer. Further, the inorganic particles occupy a predetermined space between the surface crosslinking structures. For this reason, the superabsorbent polymer may exhibit an improved water absorption rate, and may also exhibit excellent permeability by maintaining the shape under volume expansion (swelling) upon absorbing water. Particularly, owing to the above-described novel surface crosslinking structure, the superabsorbent polymer may exhibit superior characteristics of being excellent in both centrifuge retention capacity and absorbency under pressure, unlike the known inverse relationship between centrifuge retention capacity and absorbency under pressure. Consequently, the superabsorbent polymer of an embodiment may exhibit superior physical properties by solving the problems of the existing superabsorbent polymers and satisfying a technical demand in the related art.
[0019] Hereinafter, the structure of the superabsorbent polymer of an embodiment and the preparation method thereof will be described in more detail.
[0020] Basically, the superabsorbent polymer of an embodiment includes the crosslinked polymers formed by crosslinking polymerization of the water-soluble ethylene-based unsaturated monomers as a base polymer powder and the surface crosslinking layer formed on the base polymer powder, like the previous superabsorbent polymers.
[0021] Additionally, in the superabsorbent polymer of an embodiment, the inorganic particles chemically bind (e.g., a covalent bond or a crosslinking bond, etc.) to the polymer chains of the crosslinked polymers present on the surface of the base polymer powder via an oxygen-containing bond or a nitrogen-containing bond derived from the crosslinkable functional group by using the above-described surface-modified inorganic particles as a crosslinkable functional group during surface crosslinking of the crosslinked polymer and the base polymer powder. Therefore, overall physical properties as described above may be improved (in particular, centrifuge retention capacity and absorbency under pressure may be improved at the same time).
[0022] With regard to the superabsorbent polymer of an embodiment, as the water-soluble ethylene-based unsaturated monomer, one or more selected from the group consisting of an anionic monomer such as acrylic acid, (meth)acrylic acid, maleic anhydride, fumaric acid, crotonic acid, itaconic acid, 2-acryloylethane sulfonic acid, 2-methacryloylethane sulfonic acid, 2-(meth)acryloylpropane sulfonic acid, or 2-(meth)acrylamide-2-methyl propane sulfonic acid, and salts thereof; a nonionic hydrophilic monomer such as (meth)acrylamide, N-substituted (meth)acrylamide, 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, methoxy polyethylene glycol (meth)acrylate, or polyethylene glycol (meth)acrylate; and an amino group-containing unsaturated monomer such as (N,N)-dimethylaminoethyl(meth)acrylate or (N,N)-dimethylaminopropyl(meth)acrylamide, and a quaternary compound thereof may be used. Among them, acrylic acid or salts thereof, for example, acrylic acid which is at least partially neutralized and/or alkali metal salts such as sodium salts thereof may be used, and it is possible to prepare a superabsorbent polymer having superior physical properties by using these monomers. When the alkali metal salt of acrylic acid is used as the monomer, acrylic acid may be used after neutralized with a basic compound such as caustic soda (NaOH). In this regard, the degree of neutralization of the water-soluble ethylene-based unsaturated monomer may be controlled in the range of about 50% to about 95%, or about 70% to about 85%. When neutralization is performed within the above range, it is possible to provide superabsorbent polymer having excellent centrifuge retention capacity without concerns about precipitation.
[0023] Further, as the internal crosslinking agent for introduction of the basic crosslinking structure into the crosslinked polymer and the base polymer powder, any internal crosslinking agent having a crosslinkable functional group which has been previously used in the preparation of the superabsorbent polymer may be used without particular limitation. In order to further improve physical properties of the superabsorbent polymer by introducing a proper crosslinking structure into the crosslinked polymer and the base polymer powder, however, a multifunctional acrylate-based compound having a plurality of ethylene oxide groups may be used as the internal crosslinking agent. More specific examples of the internal crosslinking agent may be one or more selected from the group consisting of polyethylene glycol diacrylate (PEGDA), glycerin diacrylate, glycerin triacrylate, non-modified or ethoxylated trimethylolpropane triacrylate (TMPTA), hexanediol diacrylate, and triethylene glycol diacrylate.
[0024] Further, in the superabsorbent polymer of an embodiment, the surface-modified inorganic particles for the preparation of the surface crosslinking layer on the base polymer powder may be inorganic particles surface-modified with the above-described crosslinkable functional group.
[0025] The inorganic particles may have a specific surface area of 5 m 2 /g to 600 m 2 /g or 100 m 2 /g to 300 m 2 /g. Within this range, the inorganic particles may be surface-modified with an appropriate number of the crosslinkable functional groups. The inorganic particles has a diameter of 5 to 500 nm, and thus an appropriate number of the inorganic particles based on the same weight may be dispersed well in the surface crosslinking layer, which is economical.
[0026] More specifically, the inorganic particles may be silica particles, alumina particles, etc.
[0027] Further, the above-described inorganic particles may be bound in an amount of about 0.01 to about 2 parts by weight, based on 100 parts by weight of the superabsorbent polymer. Consequently, a crosslinking structure including an appropriate amount of the inorganic particles is introduced into the surface crosslinking layer, and therefore, the superabsorbent polymer of an embodiment may have more improved physical properties, for example, centrifuge retention capacity and absorbency under pressure. Meanwhile, a more specific kind of the surface-modified inorganic particles and a preparation method thereof are provided for reference in the after-mentioned preparation method.
[0028] In the superabsorbent polymer of an embodiment, the surface crosslinking layer formed on the base polymer powder may be formed by using a surface crosslinking agent which has been previously used in the preparation of the superabsorbent polymer, together with the surface-modified inorganic particles. As the surface crosslinking agent, any surface crosslinking agent known in the art to which the present invention pertains may be used without particular limitation. A more specific example thereof may be one or more selected from the group consisting of ethylene glycol, 1,4-butanediol, 1,6-hexanediol, propylene glycol, 1,2-hexanediol, 1,3-hexanediol, 2-methyl-1,3-propanediol, 2,5-hexanediol, 2-methyl-1,3-pentanediol, 2-methyl-2,4-pentanediol, tripropylene glycol, glycerol, ethylene carbonate and propylene carbonate.
[0029] The above-described superabsorbent polymer of an embodiment may exhibit characteristics that centrifuge retention capacity (CRC) for a physiological saline solution is about 30 g/g to about 40 g/g, absorbency under pressure (AUP) of 0.7 psi for the physiological saline solution is about 10 g/g to about 26 g/g or about 20 g/g to about 26 g/g, and free swell gel bed permeability (GBP) is about 5 darcy to about 120 darcy or about 9 darcy to about 120 darcy.
[0030] The above-described superabsorbent polymer of an embodiment may exhibit excellent centrifuge retention capacity, together with more improved permeability and absorbency under pressure, by introducing the surface crosslinking structure including inorganic particles into the surface crosslinking layer. Accordingly, the superabsorbent polymer is preferably applied to a variety of hygiene products such as diapers, etc., thereby exhibiting very excellent physical properties.
[0031] Meanwhile, the centrifuge retention capacity (CRC) for a physiological saline solution may be measured according to EDANA WSP 241.2. More specifically, the centrifuge retention capacity may be calculated by the following Equation 1, after the superabsorbent polymer is immersed in the physiological saline solution for 30 minutes:
[0000] CRC(g/g)={[ W 2(g)− W 1(g)]/ W 0(g)}−1 [Equation 1]
[0032] wherein W0(g) is the initial weight (g) of the superabsorbent polymer, W1(g) is the weight of an empty bag which is measured after immersing the empty bag in the physiological saline solution at room temperature for 30 minutes and draining water off at 250 G for 3 minutes with a centrifuge, and W2(g) is the weight of the bag including the superabsorbent polymer, which is measured after immersing the bag including the superabsorbent polymer in the physiological saline solution at room temperature for 30 minutes and draining water off at 250 G for 3 minutes with a centrifuge.
[0033] The absorbency under pressure (AUP) of 0.7 psi may be measured according to EDANA WSP 242. More specifically, the absorbency under pressure may be calculated by the following Equation 2, after immersing the superabsorbent polymer in the physiological saline solution under a pressure of about 0.7 psi for 1 hour:
[0000] AUP(g/g)=[ W 4(g)− W 3(g)]/ W 0(g) [Equation 2]
[0000] wherein W0(g) is the initial weight (g) of the superabsorbent polymer, W3(g) is the total weight of the superabsorbent polymer and an apparatus capable of providing a load for the superabsorbent polymer, and W4(g) is the total weight of the superabsorbent polymer and the apparatus capable of providing a load for the superabsorbent polymer, which are measured after immersing the superabsorbent polymer in the physiological saline solution under a load of about 0.7 psi for 1 hour.
[0034] W0(g) in Equations 1 to 2 may be, corresponding to the initial weight (g) of the superabsorbent polymer before immersing the superabsorbent polymer in the physiological saline solution, the same as or different from each other.
[0035] The gel bed permeability (GBP) for the physiological saline solution may be measured as a unit of Darcy or cm 2 according to a method described in Patent Application No. 2014-7018005. 1 Darcy means a flow of 1 mm per 1 sec of a fluid with a viscosity 1 cP under a pressure gradient of 1 atm per 1 cm acting across an area of 1 cm 2 . Gel bed permeability has the same units as area, and 1 darcy is equal to 0.98692×10 −12 m 2 or 0.98692×10 −8 cm 2 .
[0036] More specifically, in this specification, GBP means permeability of a swollen gel layer (or bed) under free swell conditions of 0 psi (Gel Bed Permeability (GBP) Under 0 psi Swell Pressure Test), and GBP may be measured by an apparatus shown in FIGS. 1 to 3 .
[0037] Referring to FIGS. 1 to 3 , in an apparatus 500 for measuring GBP, a test apparatus assembly 528 includes a sample container 530 and a plunger 536 . The plunger includes a shaft 538 having a cylinder hole bored down the longitudinal axis and a head 550 positioned at the bottom of the shaft. The shaft hole 562 has a diameter of about 16 mm. The plunger head is attached to the shaft, for example, by an adhesive. Twelve holes 544 are bored into the radial axis of the shaft, and three holes positioned at every 90 degrees have diameters of about 6.4 mm. The shaft 538 is machined from a LEXAN rod or equivalent material and has an outer diameter of about 2.2 cm and an inner diameter of about 16 mm. The plunger head 550 has a concentric inner ring of seven holes 560 and an outer ring of 14 holes 554 , all holes having a diameter of about 8.8 millimeters as well as a hole of about 16 mm aligned with the shaft. The plunger head 550 is machined from a LEXAN rod or equivalent material and has a height of approximately 16 mm and a diameter sized such that it fits within the cylinder 534 with minimum wall clearance but still slides freely. The total length of the plunger head 550 and shaft 538 is about 8.25 cm, but may be machined at the top of the shaft to obtain the desired mass of the plunger 536 . The plunger 536 includes a 100 mesh stainless steel cloth screen 564 that is biaxially stretched to tautness and attached to the lower end of the plunger 536 . The screen is attached to the plunger head 550 using an appropriate solvent that causes the screen to be securely adhered to the plunger head 550 . Care must be taken to avoid excess solvent migrating into the open portions of the screen and reducing the open area for liquid flow. Acrylic solvent Weld-on 4 from IPS Corporation (having a place of business in Gardena, Calif., USA) is a suitable solvent. The sample container 530 includes a cylinder 534 and a 400 mesh stainless steel cloth screen 566 that is biaxially stretched to tautness and attached to the lower end of the cylinder 534 . The screen is attached to the cylinder using an appropriate solvent that causes the screen to be securely adhered to the cylinder. Care must be taken to avoid excess solvent migrating into the open portions of the screen and reducing the open area for liquid flow. Acrylic solvent Weld-on 4 from IPS Corporation (having a place of business in Gardena, Calif., USA) is a suitable solvent. A gel particle sample (swollen superabsorbent polymer), indicated by 568 in FIG. 2 , is supported on the screen 566 within the cylinder 534 during testing.
[0038] The cylinder 534 may be bored from a transparent LEXAN rod or equivalent material, or it may be cut from a LEXAN tubing or equivalent material, and has an inner diameter of about 6 cm (e.g., a cross-sectional area of about 28.27 cm 2 ), a wall thickness of about 0.5 cm and a height of about 7.95 cm. A step is machined into the outer diameter of the cylinder 534 such that a region 534 a with an outer diameter of 66 mm exists for the bottom 31 mm of the cylinder 534 . An o-ring 540 which fits the diameter of region 534 a may be placed at the top of the step.
[0039] The annular weight 548 has a counter-bored hole about 2.2 cm in diameter and 1.3 cm deep so that it slips freely onto the shaft 538 . The annular weight also has a thru-bore 548 a of about 16 mm. The annular weight 548 may be made from stainless steel or from other suitable materials resistant to corrosion in the presence of 0.9% by weight of a physiological saline solution (sodium chloride solution). The combined weight of the plunger 536 and annular weight 548 equals approximately 596 g, which corresponds to a pressure applied to the sample 568 of about 0.3 psi, or about 20.7 dyne/cm 2 (2.07 kPa), over a sample area of about 28.27 cm 2 .
[0040] When the test solution flows through the test apparatus during GBP testing, the sample container 530 generally rests on a weir 600 . The purpose of the weir is to divert liquid that overflows the top of the sample container 530 and diverts the overflow liquid to a separate collection device 601 . The weir may be positioned above a scale 602 with a beaker 603 resting on it to collect the physiological saline solution passing through the swollen sample 568 .
[0041] To conduct the gel bed permeability test under “free swell” conditions, the plunger 536 , with the weight 548 seated thereon, is placed in an empty sample container 530 , and the height from the top of the weight 548 to the bottom of the sample container 530 is measured using a suitable gauge accurate to 0.01 mm. The force the thickness gauge applies during measurement should be as low as possible, preferably less than about 0.74 N. When a multiple test apparatus is used, it is important to measure the height of each sample container 530 empty and to keep track of which plunger 536 and weight 248 are used.
[0042] Desirably, the base on which the sample container 530 is placed is flat, and the top surface of the weight 548 is parallel to the bottom surface of the sample container 530 . The sample to be tested for GBP is prepared from a superabsorbent polymer, for example, which is prescreened through a US standard 30 mesh screen and retained on a US standard 50 mesh screen. As a result, a superabsorbent polymer having a diameter of about 300 μm to about 600 μm is prepared as the test sample. Approximately 2.0 g of the sample is placed in the sample container 530 and spread out evenly on the bottom of the sample container. The container, with 2.0 g of sample in it, without the plunger 536 and weight 548 therein, is then submerged in the 0.9% by weight of physiological saline solution for about 60 minutes to allow the sample to swell free of any restraining load. In this regard, the sample container 530 is set on a mesh located in the liquid reservoir so that the sample container 530 is raised slightly above the bottom of the liquid reservoir. The mesh does not inhibit the flow of the physiological saline solution into the sample container 530 . A suitable mesh may be obtained as part number 7308 from Eagle Supply and Plastic (having a place of business in Appleton, Wis., USA). Also, depth of the physiological saline solution during saturation may be controlled so that the surface within the sample container is defined solely by the sample, rather than the physiological saline solution.
[0043] At the end of this period, the plunger 536 and weight 548 assembly is placed on the saturated sample 568 in the sample container 530 , and then the sample container 530 , plunger 536 , weight 548 , and sample 568 are removed from the solution. After removal and before being measured, the sample container 530 , plunger 536 , weight 548 , and sample 568 are to remain at rest for about 30 seconds on a suitable flat, large grid non-deformable plate of uniform thickness. The plate will prevent liquid in the sample container from being released onto a flat surface due to surface tension. The plate has an overall dimension of 7.6 cm×7.6 cm, and each grid has a size dimension of 1.59 cm long×1.59 cm wide×1.12 cm deep. A suitable plate material is a parabolic diffuser panel, catalogue number 1624K27, available from McMaster Carr Supply Company (having a place of business in Chicago, Ill., USA), which may then be cut to the proper dimensions.
[0044] The height from the top of the weight 548 to the bottom of the sample container 530 is measured again using the same thickness gauge used previously, provided that the zero point is unchanged from the initial height measurement. The height measurement should be made as soon as practicable after the thickness gauge is engaged. The height measurement obtained from measuring the empty assembly where the plunger 536 and the weight 548 are placed in the empty sample container 530 is subtracted from the height measurement obtained after saturating the sample 568 . The resulting value is the thickness, or height “H” of the saturated sample 568 . Further, if the plate is included in the assembly including the saturated sample 568 , the plate must also be present when measuring the height of the empty assembly.
[0045] The GBP measurement is initiated by delivering a flow of the 0.9% physiological saline solution into the sample container 530 with the saturated sample 568 , plunger 536 , and weight 548 inside. The flow rate of the physiological saline solution into the container is adjusted to cause saline solution to overflow the top of the cylinder 534 , resulting in a consistent head pressure equal to the height of the sample container 530 . The physiological saline solution may be added by any suitable means that is sufficient to ensure a small, but consistent amount of overflow from the top of the cylinder with a metering pump 604 . The overflow liquid is diverted into a separate collection device 601 . The quantity of solution passing through the sample 568 versus time is measured gravimetrically using the scale 602 and beaker 603 . Data points from the scale 602 are collected every second for at least sixty seconds once the overflow has begun. Data collection may be taken manually or with data collection software. The flow rate, Q through the swollen sample 568 is determined in units of g/sec by a linear least-square fit of fluid (g) passing through the sample 568 versus time (sec).
[0046] Data thus obtained are used to calculate GBP (cm 2 ) according to the following Equation 3, thereby obtaining gel bed permeability.
[0000] K=[Q*H*μ]/[A*ρ*P] [Equation 3]
[0047] wherein K is a gel bed permeability (cm 2 ),
[0048] Q is a flow rate (g/sec),
[0049] H is a height of the swollen sample (cm),
[0050] ρ is a liquid viscosity (P) (approximately 1 cP for the test solution used in this test),
[0051] A is a cross-sectional area for liquid flow (28.27 cm 2 for the sample container used in this test),
[0052] ρ is a liquid density (g/cm 3 ) (approximately 1 g/cm 3 for the test solution used in this test) and
[0053] P is a hydrostatic pressure (dyne/cm 2 ) (normally approximately 7,797 dyne/cm 2 ).
[0054] The hydrostatic pressure is calculated from P=ρ*g*h, wherein p is a liquid density (g/cm 3 ), g is a gravitational acceleration (nominally 981 cm/sec 2 ), and h is a fluid height (e.g., 7.95 cm for the GBP test described herein).
[0055] The above-described superabsorbent polymer of an embodiment may be a spherical or amorphous particle having a diameter of about 150 μm to about 850 μm.
[0056] Meanwhile, according to another embodiment of the present invention, provided is a method of preparing the above-described superabsorbent polymer. The method of preparing the superabsorbent polymer may include the steps of performing crosslinking polymerization of water-soluble ethylene-based unsaturated monomers having acidic groups which are at least partially neutralized, in the presence of an internal crosslinking agent to form a hydrogel polymer; drying, pulverizing, and classifying the hydrogel polymer to form the base polymer powder; and additionally crosslinking the surface of the base polymer powder in the presence of inorganic particles surface-modified with one or more functional groups selected from the group consisting of an epoxy group, a hydroxy group, an isocyanate group, and an amine group to form the surface crosslinking layer.
[0057] In the preparation method of another embodiment, crosslinking polymerization of water-soluble ethylene-based unsaturated monomers is performed in the presence of an internal crosslinking agent, and the resulting polymer is dried, pulverized, and classified to form the base polymer powder according to a general preparation method of the superabsorbent polymer. Thereafter, unlike the previous methods, the surface of the base polymer powder is additionally crosslinked using inorganic particles, which are surface-modified with crosslinkable functional groups such as an epoxy group, a hydroxy group, an isocyanate group, and an amine group, to prepare the superabsorbent polymer.
[0058] That is, in the preparation method of another embodiment, the superabsorbent polymer may be prepared according to the general preparation method, except that the surface-modified inorganic particles are used upon surface crosslinking, and therefore, the surface-modified inorganic particles and a preparation method thereof will be first described, and then each step of the method of preparing the superabsorbent polymer using the same will be briefly described.
[0059] The surface-modified inorganic particles may be prepared by reacting a surface modifier having a crosslinkable functional group and inorganic particles such as silica particles or alumina particles. In this regard, a specific example of the surface modifier may be a compound represented by the following Chemical Formula 1:
[0000]
[0060] wherein R 1 to R 3 are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or halogen, and at least one of them is not an alkyl group, and R 4 is a substituent having 2 to 10 carbon atoms, which has one or more functional groups selected from the group consisting of an epoxy group, a hydroxy group, an isocyanate group, and an amine group.
[0061] With regard to the surface-modified inorganic particles, it is desirable that the inorganic particles are surface-modified by introducing about 2 to about 200, or about 10 to about 150, or about 20 to about 100 crosslinkable functional groups into one inorganic particle. Consequently, an appropriate crosslinking structure may be introduced into the superabsorbent polymer finally prepared by the above preparation method. Considering the appropriate number of the crosslinkable functional groups introduced into one inorganic particle, the inorganic particles and the surface modifier are reacted in a proper appropriate to prepare the surface-modified inorganic particles.
[0062] More specifically, the inorganic particles may be exemplified by silica particles such as fumed silica or colloidal silica. Of them, when fumed silica is used, the inorganic particle and the surface modifier may be reacted so that the surface of the silica particle is modified with the crosslinkable functional group at a ratio of about 0.008 umol/m 2 to about 0.8 umol/m 2 , or about 0.04 umol/m 2 to about 0.4 umol/m 2 , based on 1 m 2 of the surface area of the silica particle. When colloidal silica is used, the inorganic particle and the surface modifier may be reacted so that the surface of the silica particle is modified with the crosslinkable functional group at a ratio of about 0.014 umol/m 2 to about 1.4 umol/m 2 , or about 0.07 umol/m 2 to about 0.7 umol/m 2 , based on 1 m 2 of the surface area of the silica particle.
[0063] In the preparation method of another embodiment, crosslinking polymerization of water-soluble ethylene-based unsaturated monomers having acidic groups which are at least partially neutralized is first performed in the presence of an internal crosslinking agent to form the hydrogel polymer.
[0064] In this regard, the kind and the structure of the internal crosslinking agent and the water-soluble ethylene-based unsaturated monomer are the same as described above, and additional descriptions thereof will be omitted.
[0065] In a monomer composition including the water-soluble ethylene-based unsaturated monomer and the internal crosslinking agent, the concentration of the water-soluble ethylene-based unsaturated monomer may be about 20% by weight to about 60% by weight or about 40% by weight to about 50% by weight, based on the total weight of the monomer composition including the above described raw materials and solvent, and properly controlled in consideration of polymerization time and reaction conditions. However, if the concentration of the monomer is too low, the yield of the superabsorbent polymer may become low, and thus an economical problem may occur. On the contrary, if the concentration of the monomer is too high, there is a process problem that a part of the monomers is precipitated, or pulverization efficiency is lowered upon pulverization of the polymerized hydrogel polymer, and the physical properties of the superabsorbent polymer may be deteriorated.
[0066] Further, the monomer composition may further include a polymerization initiator which is generally used in the preparation of the superabsorbent polymer.
[0067] Specifically, the polymerization initiator may be a thermal polymerization initiator or a photo-polymerization initiator by UV irradiation, depending on a polymerization method. However, even though the photo-polymerization is performed, a certain amount of heat may be generated by UV irradiation or the like, and also generated with exothermic polymerization reaction. Therefore, the thermal polymerization initiator may be further included.
[0068] As the photo-polymerization initiator, a compound capable of forming radicals by a light such as UV may be used without limitations in the constitution.
[0069] For example, as the photo-polymerization initiator, one or more selected from the group consisting of benzoin ether, dialkyl acetophenone, hydroxyl alkylketone, phenyl glyoxylate, benzyl dimethyl ketal, acyl phosphine, and α-aminoketone may be used. Of them, acyl phosphine may be used as the photo-polymerization initiator. The acyl phosphine may be diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, phenylbis(2,4,6-trimethyl benzoyl)phosphine oxide, ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate, etc. More various photo-polymerization initiators are well disclosed in “UV Coatings: Basics, Recent Developments and New Application (Elsevier, 2007)” written by Reinhold Schwalm, p 115, however, they are not limited to the above described examples.
[0070] The concentration of the photo-polymerization initiator may be about 0.001% by weight to about 1.0% by weight, based on the total weight of the monomer composition. If the concentration of the photo-polymerization initiator is too low, the polymerization rate may become low. If the concentration of the photo-polymerization initiator is too high, the molecular weight of the superabsorbent polymer may become low and its physical properties may be not uniform.
[0071] Further, as the thermal polymerization initiator, one or more selected from the group consisting of persulfate-based initiators, azo-based initiators, hydrogen peroxide, and ascorbic acid may be used. Specific examples of the persulfate-based initiators may include sodium persulfate (Na 2 S 2 O 8 ), potassium persulfate (K 2 S 2 O 8 ), ammonium persulfate (NH 4 ) 2 S 2 O 8 ) or the like. Examples of the azo-based initiators may include 2,2-azobis(2-amidinopropane)dihydrochloride, 2,2-azobis-(N,N-dimethylene)isobutyramidine dihydrochloride, 2-(carbamoylazo)isobutylonitril, 2,2-azobis(2-[2-imidazolin-2-yl]propane)dihydrochloride, 4,4-azobis-(4-cyanovaleric acid) or the like. More various thermal polymerization initiators are well-disclosed in ‘Principle of Polymerization (Wiley, 1981)’ written by Odian, p 203, however, they are not limited to the above described examples.
[0072] The concentration of the thermal polymerization initiator may be about 0.001% by weight to about 0.5% by weight, based on the total weight of the monomer composition. If the concentration of the thermal polymerization initiator is too low, additional thermal polymerization hardly occurs, and thus the addition effect of the thermal polymerization initiator may not be sufficiently obtained. If the concentration of the thermal polymerization initiator is too high, the molecular weight of the superabsorbent polymer may become low and the content of water-soluble components is increased, thereby deteriorating absorbency under pressure of a final superabsorbent polymer product.
[0073] The kind of the internal crosslinking agent included in the monomer composition is the same as described above, and the internal crosslinking agent may be included in an amount of about 0.01% by weight to about 0.5% by weight, based on the monomer composition, thereby crosslinking the polymerized polymer. In particular, when the internal crosslinking agent is used in an amount of about 0.3 parts by weight or more, or about 0.3 parts by weight to about 0.6 parts by weight, based on 100 parts by weight of the above-described monomer, for example, non-neutralized acrylic acid, it is possible to prepare a superabsorbent polymer which more properly satisfies the above described physical properties of an embodiment.
[0074] The monomer composition may further include an additive such as a thickener, a plasticizer, a preservation stabilizer, an antioxidant, etc., if necessary.
[0075] The raw materials such as the above-described water-soluble ethylene-based unsaturated monomer, photo-polymerization initiator, thermal polymerization initiator, internal crosslinking agent, and additive may be prepared in the form of a solution of the monomer composition which is dissolved in a solvent.
[0076] In this regard, as the solvent, any solvent may be used without limitations in the constitution as long as it is able to dissolve the above ingredients, and for example, one or more selected from water, ethanol, ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, propylene glycol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl ethyl ketone, acetone, methyl amyl ketone, cyclohexanone, cyclopentanone, diethylene glycol monomethyl ether, diethylene glycol ethylether, toluene, xylene, butyrolactone, carbitol, methyl cellosolve acetate and N,N-dimethylacetamide may be used in combination.
[0077] The solvent may be included in a residual amount of excluding the above described components from the total weight of the monomer composition.
[0078] Meanwhile, as long as the method for forming the hydrogel polymer by thermal polymerization or photo-polymerization of the monomer composition is a method generally used, there is no particular limitation in the constitution.
[0079] Specifically, the polymerization method is largely classified into the thermal polymerization and the photo-polymerization according to the polymerization energy source. The thermal polymerization may be carried out in a reactor like a kneader equipped with agitating spindles, and the photo-polymerization may be carried out in a reactor equipped with a movable conveyor belt. The above-described polymerization method is an example only, and the present invention is not limited thereto.
[0080] For example, thermal polymerization of the monomer composition may be performed by providing hot air for a reactor like a kneader equipped with the agitating spindles or heating the reactor. The hydrogel polymer thus obtained by thermal polymerization may have the size of centimeters or millimeters when it is discharged from the outlet of the reactor, according to the type of agitating spindles equipped in the reactor. Specifically, the hydrogel polymer may be obtained in various forms according to the concentration of the monomer composition fed thereto, the feeding speed or the like, and the hydrogel polymer having a weight average particle size of about 2 mm to about 50 mm may be generally obtained.
[0081] Further, as described above, when the photo-polymerization is carried out in a reactor equipped with a movable conveyor belt, the hydrogel polymer generally obtained may be a hydrogel polymer in a sheet-type having a width of the belt. In this regard, the thickness of the polymer sheet may vary according to the concentration of the monomer composition fed thereto and the feeding speed, and the feeding speed of the monomer composition is preferably controlled so that the polymer sheet having a thickness of about 0.5 cm to about 5 cm is obtained. If the monomer composition is fed so that the thickness of the sheet-type polymer becomes too thin, the production efficiency becomes low, which is not preferred. If the thickness of the sheet-type polymer exceeds 5 cm, the polymerization reaction may not uniformly occur throughout the polymer due to the excessively high thickness.
[0082] A light source to be used in the photo-polymerization method is not particularly limited, and a non-limiting example thereof may be a light source such as a Xe lamp, a mercury lamp, a metal halide lamp, etc.
[0083] Meanwhile, the monomer composition may be thermally polymerized after it is photo-polymerized. In this case, a reactor capable of providing a movable conveyor belt, a UV light source, and hot air may be used, and photo-polymerization and thermal polymerization may be sequentially performed.
[0084] The hydrogel polymer thus obtained by the method may have generally a water content of about 40% by weight to about 80% by weight. Meanwhile, the term “water content”, as used herein, means a water content in the total weight of the hydrogel polymer, which is obtained by subtracting the weight of the dry polymer from the weight of the hydrogel polymer. Specifically, the water content is defined as a value calculated by measuring the weight loss according to evaporation of water in the polymer during the drying process of increasing the temperature of the polymer with infrared heating. In this regard, the water content is measured under the drying conditions which are determined as follows; the temperature is increased from room temperature to about 180° C. and then the temperature is maintained at 180° C., and the total drying time is determined as 20 minutes, including 5 minutes for the temperature rising step.
[0085] After crosslinking polymerization of the monomer, drying, pulverizing, and classifying processes may be performed to obtain the base polymer powder. Through the pulverizing and classifying processes, the base polymer powder and the superabsorbent polymer obtained therefrom are properly prepared to have a particle size of about 150 μm to about 850 μm. More specifically, about 95% by weight or more of the base polymer powder and the superabsorbent polymer obtained therefrom have a particle size of about 150 μm to 850 μm, and the content of fine powder having a particle size of less than about 150 μm may be less than about 3% by weight.
[0086] As the particle size distributions of the base polymer powder and the superabsorbent polymer are controlled within the preferred range, the final superabsorbent polymer may exhibit the above-described physical properties and more excellent permeability.
[0087] Meanwhile, the drying, pulverizing, and classifying processes are described in more detail as follows.
[0088] First, in the process of drying the hydrogel polymer, the step of coarsely pulverizing the hydrogel polymer may be performed before the drying process, in order to increase efficiency of the drying process, if necessary.
[0089] In this regard, a pulverizing device applicable may include, but the constitution is not limited, any one selected from the group consisting of a vertical pulverizer, a turbo cutter, a turbo grinder, a rotary cutter mill, a cutter mill, a disc mill, a shred crusher, a crusher, a chopper, and a disc cutter, but is not limited thereto.
[0090] In this regard, the coarse pulverization may be performed so that the hydrogel polymer has a particle size of about 2 mm to about 10 mm.
[0091] To pulverize the hydrogel polymer at a particle size of less than 2 mm is technically not easy due to its high water content, and agglomeration may occur between the pulverized particles. If the hydrogel polymer is pulverized at a particle size of more than 10 mm, the effect of increasing the efficiency in the subsequent drying step may become insignificant.
[0092] The hydrogel polymer coarsely pulverized as above or immediately after polymerization without the coarse pulverization is subjected to a drying process. In this regard, the drying temperature of the drying step may be about 100° C. to about 250° C.
[0093] When the drying temperature is lower than 100° C., the drying time becomes excessively long or the physical properties of the superabsorbent polymer finally formed may be deteriorated, and when the drying temperature is higher than 250° C., only the surface of the polymer is dried, and thus fine powder may be generated during the subsequent pulverization process, and the physical properties of the superabsorbent polymer finally formed may be deteriorated.
[0094] Any known drying method may be selected and used in the drying step without limitation in the constitution as long as it may be generally used for drying the hydrogel polymer. Specifically, the drying step may be carried out by a method of supplying hot air, irradiating infrared rays, irradiating microwaves, irradiating ultraviolet rays or the like. When the drying step as above is finished, the water content of the polymer may be about 0.1% by weight to about 10% by weight.
[0095] Next, the dried polymer obtained from the drying step is subjected to a pulverization step.
[0096] The polymer powder obtained from the pulverization step may have a particle size of about 150 μm to about 850 μm. A specific example of a milling device which may be used to pulverize the polymer within the above particle size range may include a pin mill, a hammer mill, a screw mill, a roll mill, a disc mill, a jog mill or the like, but the present invention is not limited thereto.
[0097] In order to manage the physical properties of the superabsorbent polymer powder finally manufactured after the pulverization step, the polymer powder obtained after the pulverization may be subjected to an additional classifying step according to the particle size. Only a polymer having a particle size of about 150 μm to about 850 μm is preferably classified and then selectively applied to the surface crosslinking reaction, and finally manufactured. The particle size distribution of the base polymer powder obtained through this process is as described above, and a specific description thereof will be omitted.
[0098] Meanwhile, after the process of forming the above-described base polymer powder, the surface of the base polymer powder is additionally crosslinked in the presence of the surface-modified inorganic particles to form the surface crosslinking layer, thereby finally preparing the superabsorbent polymer.
[0099] In this regard, the kind and structure of the surface-modified inorganic particles are as described above, and additional descriptions thereof will be omitted.
[0100] The surface-modified inorganic particles may be used in an amount of 0.01 to 10 parts by weight, 0.01 to 5 parts by weight or 0.01 to 3 parts by weight, based on 100 parts by weight of the base polymer powder. When the surface-modified inorganic particles are used within the above range, the superabsorbent polymer having excellent centrifuge retention capacity and absorbency under pressure and improved permeability may be prepared.
[0101] Further, for a proper surface crosslinking density of the surface crosslinking layer, a surface crosslinking agent generally used in the surface crosslinking of the superabsorbent polymer may be used, together with the surface-modified inorganic particles. The kind of the surface crosslinking agent is as described above, and an additional description thereof will be omitted.
[0102] In the surface crosslinking process, the surface crosslinking reaction is performed by adding polyvalent metal cations, together with the surface-modified inorganic particles, thereby further optimizing the surface crosslinking structure of the superabsorbent polymer. It is assumed that the metal cations are chelated by the carboxylic groups (COOH) of the superabsorbent polymer, thereby further reducing the crosslinking distance.
[0103] With regard to the method of adding the surface-modified inorganic particles to the base polymer powder, there is no limitation in the constitution. For example, a method of adding and mixing the surface-modified inorganic particles and the base polymer powder in a reactor, a method of spraying the surface-modified inorganic particles onto the base polymer powder, or a method of continuously feeding the base polymer powder and the surface-modified inorganic particles to a mixer which is continuously operated may be used.
[0104] When the surface-modified inorganic particles are added, a mixture of water and methanol may be further added. When water and methanol are added, there is an advantage that the surface-modified inorganic particles are uniformly dispersed in the base polymer powder. In this regard, the contents of water and methanol added may be properly controlled, in order to induce uniform dispersion of the surface-modified inorganic particles, to prevent agglomeration of the base polymer powder, and to optimize the surface penetration depth of the inorganic particles.
[0105] The surface-modified inorganic particles are added to the base polymer powder, and then they may be heated at about 100° C. to about 200° C. for about 1 minute to about 120 minutes to allow the surface crosslinking reaction. More specifically, the surface crosslinking reaction may be allowed for about 1 minute to about 120 minutes, about 5 minutes to about 100 minutes, or about 10 minutes to about 80 minutes, after temperature reaches the target temperature for the reaction. If the crosslinking reaction time is excessively shorter than the above, sufficient surface crosslinking reaction may not occur. If the crosslinking reaction time is excessively long, the physical properties of the superabsorbent polymer may be deteriorated due to excessive surface crosslinking reaction, and degradation of the superabsorbent polymer may occur due to long retention of the polymer in the reactor.
[0106] A means for raising the temperature for surface crosslinking reaction is not particularly limited. Heating may be performed by providing a heating medium or by directly providing a heat source. In this regard, the type of the heating medium applicable may be a hot fluid such as steam, hot air, hot oil, or the like. However, the present invention is not limited thereto. The temperature of the heating medium provided may be properly controlled, considering the means of the heating medium, the heating rate, and the target temperature. Meanwhile, as the heat source provided directly, an electric heater or a gas heater may be used, but the present invention is not limited to these examples.
[0107] The superabsorbent polymer obtained according to the above-described preparation method may exhibit excellent characteristics of having improved physical properties such as centrifuge retention capacity and absorbency under pressure, thereby being properly applied to hygiene products such as diapers, etc.
Effect of the Invention
[0108] According to the present invention, provided are a superabsorbent polymer and a preparation method thereof, in which the superabsorbent polymer may exhibit superior characteristics of being excellent in both centrifuge retention capacity and absorbency under pressure, unlike the known inverse relationship between centrifuge retention capacity and absorbency under pressure.
[0109] Consequently, the superabsorbent polymer of the present invention may exhibit superior physical properties by solving the problems of the existing superabsorbent polymers and satisfying a technical demand in the related art, thereby being very preferably applied to a variety of hygiene products.
BRIEF DESCRIPTION OF DRAWINGS
[0110] FIGS. 1 to 3 illustrate an exemplary apparatus for measuring gel bed permeability and components equipped in the apparatus.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0111] Hereinafter, the preferred Examples are provided for better understanding. However, the following Examples are for illustrative purposes only, and the present invention is not intended to be limited by following Examples.
Preparation Example 1: Preparation of Surface-Modified Inorganic Particles (Introduction of Epoxy Group)
[0112] 5% by weight of Aerosil 200 (Evonik) was dispersed in water to prepare 100 g of a solution. Subsequently, 1 mL of acetic acid was added to this solution to adjust pH to 3. Then, 2 g of (3-(glycidyloxy)propyl)trimethoxysilane was added thereto. To the solution thus obtained, 70 g of 1 mm bead (ZrO 2 ) was added, and mixed for about 24 hours to modify the surface of the inorganic particles. A product thus obtained was washed with n-butyl acetate to obtain surface-modified inorganic particles.
Preparation Example 2: Preparation of Surface-Modified Inorganic Particles (Introduction of Epoxy Group)
[0113] 200 g of IPA (iso-propyl alcohol) and 12 g of (3-(glycidyloxy)propyl)trimethoxysilane were added to 100 g of Ludox HSA (silica content: 30% by weight). To the solution thus obtained, 70 g of 1 mm bead (ZrO 2 ) was added, and mixed for about 24 hours to modify the surface of the inorganic particles. A product thus obtained was washed with n-butyl acetate to obtain surface-modified inorganic particles.
[0114] (Ludox HSA is colloidal silica having a particle size of 12 nm and a specific surface area of 215 m 2 /g)
Example 1: Preparation of Superabsorbent Polymer
[0115] 100 g of acrylic acid, 38.9 g of caustic soda (NaOH), and 103.9 g of water were mixed. To this mixture, 0.01 g of a photo-polymerization initiator, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.18 g of a thermal polymerization initiator, sodium persulfate, and 0.35 g of an internal crosslinking agent, polyethylene glycol diacrylate were added to prepare a monomer composition. Temperature of the monomer composition was maintained at 40° C. in a water bath.
[0116] Meanwhile, for photo-polymerization and thermal polymerization of the monomer composition, used was an apparatus which was equipped with a biaxial rotary silicon belt and a mercury lamp placed on the belt and was able to provide hot air for an insulated space after UV irradiation.
[0117] The monomer composition of which temperature was controlled in the water bath was fed to the belt of the apparatus. The monomer composition on the belt was irradiated with UV at an intensity of 10 mW for 60 seconds using the mercury lamp placed on the top of the belt. After UV irradiation, hot air was provided for the photo-polymerized polymer to maintain temperature at 90° C. for thermal polymerization. Thereafter, a hydrogel polymer discharged through a cutter was dried in a hot air dryer at 180° C. for 1 hour.
[0118] The hydrogel polymer thus dried was pulverized using a pin mill pulverizer. Thereafter, the polymer was classified into a polymer having a particle size of less than about 150 μm and a polymer having a particle size of about 150 μm to about 850 μm using a sieve.
[0119] Thereafter, a surface treatment solution including 1.0 part by weight of 1,3-propanediol, 1 part by weight of water, and 0.1 part by weight of the surface-modified inorganic particles prepared in Preparation Example 1, based on 100 parts by weight of the prepared base polymer powder, was sprayed and stirred at room temperature to uniformly distribute the surface crosslinking agent and the surface treatment solution in the base polymer powder.
[0120] Thereafter, the mixture was fed to a surface crosslinking reactor set at about 180° C. to allow surface crosslinking reaction. In the surface crosslinking reactor, the temperature of the base polymer powder was gradually increased from the initial temperature near about 160° C., and reached a maximum temperature of about 180° C. after about 30 minutes. After reaching the maximum reaction temperature, additional reaction was allowed for about 20 minutes, thereby obtaining a final superabsorbent polymer sample. After the surface crosslinking process, a surface-crosslinked superabsorbent polymer having a particle size of about 150 μm to about 850 μm was obtained by using a sieve. The content of fine powder having a particle size of about 150 μm or less in the superabsorbent polymer was less than about 2% by weight.
Example 2: Preparation of Superabsorbent Polymer
[0121] A superabsorbent polymer was prepared in the same manner as in Example 1, except that 0.3 parts by weight of the surface-modified inorganic particles was used, based on 100 parts by weight of the base polymer powder, in Example 1. The content of fine powder having a particle size of about 150 μm or less in the superabsorbent polymer was less than about 2% by weight.
Comparative Example 1: Preparation of Superabsorbent Polymer
[0122] A superabsorbent polymer was prepared in the same manner as in Example 1, except that the surface-modified inorganic particles were not used in Example 1.
Comparative Example 2: Preparation of Superabsorbent Polymer
[0123] 0.1 part by weight Aerosil 200 (Evonik) was added to and mixed with 100 parts by weight of the superabsorbent polymer prepared in Comparative Example 1.
Comparative Example 3: Preparation of Superabsorbent Polymer
[0124] 0.3 part by weight Aerosil 200 (Evonik) was added to and mixed with 100 parts by weight of the superabsorbent polymer prepared in Comparative Example 1.
[0125] Experimental Example: Test of Physical Properties of Superabsorbent Polymer Portions of the superabsorbent polymers prepared in Example 1, Example 2, Comparative Example 2, and Comparative Example 3 were taken and classified for 10 minutes using a testing sieve having a mesh size of #100 to remove dust from the superabsorbent polymers (Dedusting process).
[0126] Physical properties of the superabsorbent polymer before and after the dedusting process were measured by the following method and given in Table 1.
[0127] (1) Centrifuge Retention Capacity (CRC)
[0128] Centrifuge retention capacity (CRC) by absorbency under no load was measured for the superabsorbent polymers according to EDANA (European Disposables and Nonwovens Association) WSP 241.2.
[0129] In detail, the polymer W0(g) (about 2.0 g) was uniformly placed into a nonwoven-fabric-made bag, followed by sealing. Then, the bag was immersed at room temperature in a physiological saline solution which is 0.9% by weight of sodium chloride aqueous solution. After 30 minutes, the bag was drained at 250 G for 3 minutes with a centrifuge, and the weight W2(g) of the bag was then measured. Further, the same procedure was carried out using no polymer, and the resultant weight W1(g) was measured.
[0130] Thus, centrifuge retention capacity (CRC (g/g)) was calculated from these weights thus obtained according to the following Equation:
[0000] CRC(g/g)={[ W 2(g)− W 1(g)]/ W 0(g)}−1 [Equation 1]
[0131] wherein W0(g) is the initial weight (g) of the superabsorbent polymer, W1(g) is the weight of the empty bag which is measured after immersing the bag in the physiological saline solution at room temperature for 30 minutes and draining water off at 250 G for 3 minutes with a centrifuge, and
[0132] W2(g) is the weight of the bag including the superabsorbent polymer, which is measured after immersing the bag including the superabsorbent polymer in the physiological saline solution at room temperature for 30 minutes and draining water off at 250 G for 3 minutes with a centrifuge.
[0133] (2) Absorbency Under Pressure (AUP)
[0134] Absorbency under pressure (AUP) was measured for the superabsorbent polymers according to EDANA (European Disposables and Nonwovens Association) WSP 242.2.
[0135] First, a 400 mesh stainless steel net was installed in the bottom of the plastic cylinder having the internal diameter of 60 mm. The superabsorbent polymers W0(g) (0.90 g), of which absorbency under pressure was intended to be measured, was uniformly scattered on the steel net at room temperature and the humidity of 50%, and a piston which may provide a load of 4.83 kPa (0.7 psi) uniformly was put thereon, in which the external diameter of the piston was slightly smaller than 60 mm, there was no gab between the internal wall of the cylinder and the piston, and the jig-jog of the cylinder was not interrupted. The weight W3(g) of the apparatus thus prepared was measured.
[0136] After putting a glass filter having a diameter of 90 mm and a thickness of 5 mm in a petri dish having a diameter of 150 mm, a physiological saline solution (0.9% by weight of sodium chloride aqueous solution) was poured in the dish until the surface level became equal to the upper surface of the glass filter. A sheet of filter paper having a diameter of 90 mm was put on the glass filter.
[0137] Subsequently, the prepared measuring apparatus was put on the filter paper, and the superabsorbent polymer in the apparatus was allowed to be swollen by the physiological saline solution under the load. After 1 hr, the weight W4(g) of the apparatus including the swollen superabsorbent polymer was measured.
[0138] The weights thus obtained were used to calculate absorbency under pressure according to the following Equation 2:
[0000] AUP(g/g)=[ W 4(g)− W 3(g)]/ W 0(g) [Equation 2]
[0139] wherein W0(g) is the initial weight (g) of the superabsorbent polymer,
[0140] W3(g) is the total weight of the superabsorbent polymer and an apparatus capable of providing a load for the superabsorbent polymer, and
[0141] W4(g) is the total weight of the superabsorbent polymer and the apparatus capable of providing a load for the superabsorbent polymer, which are measured after immersing the superabsorbent polymer in the physiological saline solution under a load of about 0.7 psi for 1 hour.
[0142] (3) Gel Bed Permeability (GBP)
[0143] The free swell gel bed permeability (GBP) of the superabsorbent polymer for the physiological saline solution was measured according to a method described in Patent Application No. 2014-7018005.
[0144] In detail, to measure free swell GBP, an apparatus shown in FIGS. 1 to 3 was used. First, a plunger 536 , with a weight 548 seated thereon, was placed in an empty sample container 530 and the height from the top of the weight 548 to the bottom of the sample container 530 was measured using a suitable gauge accurate to 0.01 mm. The force the thickness gauge applies during measurement was controlled to less than about 0.74 N.
[0145] Meanwhile, a superabsorbent polymer to be tested for GBP was prepared from superabsorbent polymers which were prescreened through a US standard 30 mesh screen and retained on a US standard 50 mesh screen. As a result, a superabsorbent polymer having a particle size of about 300 μm to about 600 μm was prepared.
[0146] Approximately 2.0 g of the superabsorbent polymer thus classified was placed in the sample container 530 and spread out evenly on the bottom of the sample container. Subsequently, the container without the plunger 536 and weight 548 therein was then submerged for about 60 minutes in the physiological saline solution which is 0.9% by weight of sodium chloride aqueous solution to swell the superabsorbent polymer under no restraining load. In this regard, the sample container 530 was set on a mesh located in the liquid reservoir so that the sample container 530 was raised slightly above the bottom of the liquid reservoir. The mesh did not inhibit the flow of the physiological saline solution into the sample container 530 . Also, depth of the physiological saline solution during saturation was controlled so that the surface within the sample container was defined solely by the swollen superabsorbent polymer, rather than the physiological saline solution.
[0147] At the end of this period, the plunger 536 and weight 548 assembly was placed on the swollen superabsorbent polymer 568 in the sample container 530 and then the sample container 530 , plunger 536 , weight 548 , and swollen superabsorbent polymer 568 were removed from the solution. After removal and before being measured, the sample container 530 , plunger 536 , weight 548 , and swollen superabsorbent polymer 568 were to remain at rest for about 30 seconds on a suitable flat, large grid non-deformable plate of uniform thickness. The height from the top of the weight 548 to the bottom of the sample container 530 was measured using the same thickness gauge used previously. The height measurement of the device where the plunger 536 and the weight 548 were placed in the empty sample container 530 was subtracted from the height measurement of the device including the swollen superabsorbent polymer 568 to obtain the thickness or height “H” of the swollen superabsorbent polymer.
[0148] The GBP measurement was initiated by delivering a flow of the physiological saline solution (0.9% by weight of sodium chloride aqueous solution) into the sample container 530 with the swollen superabsorbent polymer 568 , plunger 536 , and weight 548 inside. The flow rate of the physiological saline solution into the sample container 530 was adjusted to cause saline solution to overflow the top of the cylinder 534 , resulting in a consistent head pressure equal to the height of the sample container 530 . The quantity of solution passing through the swollen superabsorbent polymer 568 versus time was measured gravimetrically using the scale 602 and beaker 603 . Data points from the scale 602 were collected every second for at least sixty seconds once the overflow had begun. The flow rate, Q through the swollen superabsorbent polymer 568 was determined in units of g/sec by a linear least-square fit of fluid (g) passing through the swollen superabsorbent polymer 568 versus time (sec).
[0149] Data thus obtained were used to calculate GBP (cm 2 ) according to the following Equation 3:
[0000] K=[Q*H*μ]/[A*ρ*P] [Equation 3]
[0150] wherein K is a gel bed permeability (cm 2 ),
[0151] Q is a flow rate (g/sec),
[0152] H is a height of the swollen superabsorbent polymer (cm),
μ is a liquid viscosity (P) (approximately 1 cP for the physiological saline solution used in this test),
[0154] A is a cross-sectional area for liquid flow (28.27 cm 2 for the sample container used in this test),
[0155] ρ is a liquid density (g/cm 3 ) (approximately 1 g/cm 3 for the physiological saline solution used in this test) and
[0156] P is a hydrostatic pressure (dyne/cm 2 ) (normally approximately 7,797 dyne/cm 2 ).
[0157] The hydrostatic pressure was calculated from P=ρ*g*h, wherein ρ is a liquid density (g/cm 3 ), g is a gravitational acceleration (nominally 981 cm/sec 2 ), and h is a fluid height (e.g., 7.95 cm for the GBP test described herein).
[0158] At least two samples were tested, and a mean value of the results was used to determine the free swell GBP of the superabsorbent polymer. The unit was converted to darcy (1 darcy=0.98692×10 −8 cm 2 ), and given in Table 1.
[0000]
TABLE 1
Before dedusting process
(After surface crosslinking)
After dedusting process
Kind of inorganic particles
CRC
AUP
GBP
CRC
AUP
GBP
(Content)
(g/g)
(g/g)
(darcy)
(g/g)
(g/g)
(darcy)
Example 1
Surface-modified inorganic
34.6
23.3
11
34.3
23.5
9
particles of Preparation
Example 1
(0.1 part by weight, based
on 100 parts by weight of
base polymer powder)
Example 2
Surface-modified inorganic
32.6
21.6
41
32.4
22.2
45
particles of Preparation
Example 1
(0.3 parts by weight, based
on 100 parts by weight of
base polymer powder)
Comparative
—
34.5
22.7
3
—
—
—
Example 1
Comparative
Aerosil 200
35.1
21.0
8
34.1
21.6
4
Example 2
(0.1 part by weight, based
on 100 parts by weight of
superabsorbent polymer)
Comparative
Aerosil 200
34.6
16.7
48
33.4
17.6
31
Example 3
(0.3 parts by weight, based
on 100 parts by weight of
superabsorbent polymer)
[0159] Referring to Table 1, the superabsorbent polymer according to an embodiment of the present invention was found to have excellent centrifuge retention capacity, absorbency under pressure, and permeability. In contrast, when any one physical property of centrifuge retention capacity, absorbency under pressure, and permeability of the superabsorbent polymers of Comparative Examples 1 to 3 was excellent, at least one of the other physical properties were poor.
[0160] Further, the superabsorbent polymers of Examples 1 and 2 maintained excellent physical properties because the inorganic particles did not break away therefrom even after the dedusting process, whereas the physical properties of the superabsorbent polymers of Comparative Examples 2 and 3 were deteriorated.
[0161] Accordingly, since the superabsorbent polymers according to an embodiment of the present invention have the surface crosslinking structure, their physical properties may be improved and deterioration in the physical properties may be minimized during the preparation and transportation of the superabsorbent polymers.
REFERENCE NUMERALS
[0000]
500 : GBP measuring apparatus
528 : Test apparatus assembly
530 : Sample container
534 : Cylinder
534 a : Region with outer diameter of 66 mm
536 : Plunger
538 : Shaft
540 : O-ring
544 , 554 , 560 : Hole
548 : Annular weight
548 a : Thru-bore
550 : Plunger head
562 : Shaft hole
564 : 100 Mesh stainless steel cloth screen
566 : 400 Mesh stainless steel cloth screen
568 : Sample
600 : Weir
601 : Collection device
602 : Scale
603 : Beaker
604 : Metering pump | The present invention relates to a super-absorbent polymer having excellent properties, both centrifugal retention capacity (CRC) and absorption under pressure (AUP) having been improved by introducing a surface crosslinked layer crosslinked by surface-modified inorganic particles, and to a method for preparing the same. The super-absorbent polymer comprises: a base resin powder containing a crosslinked polymer of water-soluble ethylene-based unsaturated monomers having an at least partially neutralized acidic group; and a surface crosslinked layer formed on the base resin powder, wherein inorganic particles may be chemically bound to the crosslinked polymer contained in the surface crosslinked layer, via an oxygen-containing bond or a nitrogen-containing bond. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to polyurethane compositions which crosslink via silane polycondensation and which comprise alkoxysilane-functional polyurethanes, basic fillers, phosphorus compounds, aminosilanes, organometallic compounds and optionally other adjuvant substances, to a method of producing them and to their use.
Alkoxysilane-functional polyurethanes which crosslink via silane polycondensation form part of the prior art which has long been known. A review article on this topic is given in “Adhesives Age” April 1995, page 30 et seq. (authors: Ta-Min Feng, B. A. Waldmann). Single-component polyurethanes of this type, which contain terminal alkoxysilane groups and which cure under the effect of moisture, are increasingly being used as flexible coating, sealing and adhesive compositions in the building trade and in the automobile industry. In these applications, stringent demands are made on the capacity of these compositions for dilatation and adhesion and on the rate of curing thereof, for example.
Products of this type are described in EP-A-596 360, EP-A 831 108, EP-A 807 649 and EP-A 676 403, for example. Organometallic catalysts, as well as bonding agents of the aminosilane type, are typically used in conjunction when formulating systems of this type. However, the addition of aminosilane compounds often results in problems of stability on storage, particularly if higher proportions of aminosilanes are used in order to achieve good adhesion to difficult substrates.
The object of the present invention was therefore to provide polyurethane compositions which contain aminosilanes and which crosslink via silane polycondensation, and which exhibit improved stability on storage.
It has proved possible to achieve this object by the provision of the polyurethane compositions which crosslink by condensation and which are described in more detail below.
SUMMARY OF THE INVENTION
The present invention relates to polyurethane compositions which crosslink via silane polycondensation, comprising
A) at least one alkoxysilane-functional polyurethane containing terminal groups of general formula (I)
wherein
R represents an organic radical comprising 1 to 12 carbon atoms,
n represents the numbers 2, 3 or 4, and
X, Y, Z constitute identical or different organic radicals, with the proviso that at least one of the radicals constitutes an alkoxy group comprising 1 to 4 carbon atoms, preferably a methoxy or an ethoxy group,
B) at least one basic filler,
C) at least one phosphorus compound from the group comprising esters of orthophosphoric acid and/or an ester or polyphosphoric acid of general formula (II)
O═P(OR′) 3−m (OH) m (II),
wherein
m represents the numbers 1 or 2,
R′ represents a linear or branched C 1 -C 30 alkyl, acyl, C 2 -C 30 alkenyl, alkoxyalkyl, C 5 -C 14 cycloalkyl or aryl radical, which is optionally substituted, or a triorganosilyl or diorganoalkoxysilyl radical, which can be the same or different within the molecule,
D)at least one aminosilane of general formula (III)
wherein
R″ represents a hydrogen atom, an aliphatic hydrocarbon radical comprising 1 to 4 carbon atoms, a trialkoxysilylpropyl group or an aminoethyl group, and n, X, Y, and Z have the meanings given for formula (I),
E) organometallic compounds, and
F) optionally other adjuvant substances.
DETAILED DESCRIPTION OF THE INVENTION
The use of organic phosphorus compounds for stabilising silicone sealing material systems, namely RTV 1 systems, is known from DE-A 19 507 416, for example. According to the teaching of the aforementioned patent, the addition of organophosphorus compounds improves the stability on storage of RTV 1 systems. In these systems, depolymerisation is prevented by the addition of said organophosphorus compounds. Of course, depolymerisation cannot occur at all in polyurethanes which comprise alkoxysilane terminal groups. In view of this fact, it is extremely surprising that the organophosphorus compounds according to the invention also have a positive effect on the stability on storage of polyurethane systems which crosslink via silane polycondensation.
Polyurethanes A) which contain alkoxysilane terminal groups are known in principle and are produced by the reaction of long-chain, preferably linear NCO prepolymers with amino-functional silanes of general formula (Ia),
wherein
R represents an organic radical comprising 1 to 12 carbon atoms, preferably a phenyl group, or represents a radical of general structural formula (Ib)
wherein
R 1 represents an alkyl group comprising 1 to 4 carbon atoms.
R most preferably represents a radical of general structural formula (II), wherein R 1 has the meaning given above.
In the above structural formula, n represents the number 2, 3 or 4, preferably 3.
X, Y and Z in the above structural formula denote identical or different organic radicals, with the proviso that at least one of the radicals constitutes an alkoxy group comprising 1 to 4 carbon atoms. At least one of the radicals is preferably a methoxy or ethoxy group. X, Y and Z most preferably each represent a methoxy group. Examples of suitable amino-functional silanes include N-methyl-3-aminopropyltrimethoxysilane, N-methyl-3-aminopropyltriethoxysilane and N-butyl-3-aminopropyl-trimethoxysilane. N-phenyl-3-aminopropyltrimethoxysilane is preferably used.
The esters of aspartic acid which are described in EP-A 596360 are most preferably used. These are produced by the reaction of aminosilanes of general structural formula (Ia) with esters of maleic or fumaric acid, of formula (IV):
In formula (Ia), n, X, Y and Z have the meanings given above for formula (I). In formula (IV), R 2 represents an alkyl radical comprising 1 to 4 carbon atoms.
The NCO prepolymers which can be used for the production of polyurethanes A) which contain alkoxysilane terminal groups are produced in the known manner by the reaction of polyether polyols, preferably polyether diols, with diisocyanates, and have an NCO content between 0.4 and 4%.
The basic fillers B) which can be used according to the invention include precipitated or ground chalk, metal oxides, sulphates, silicates, hydroxides, carbonates and hydrogen carbonates. Examples of other fillers include reinforcing and non-reinforcing fillers, such as pyrogenic or precipitated hydrated silicas, carbon black or quartz powder. Both the basic fillers and the other reinforcing or non-reinforcing fillers may optionally be present in surface-modified form. Precipitated or ground chalk and pyrogenic hydrated silicas, the surfaces of which may optionally be treated, are preferably used as basic fillers B). Component B) may also of course comprise mixtures of fillers.
Phosphorus compounds C) according to the invention are esters of orthophosphoric acid and phosphoric acid or mixtures thereof. The esters of orthophosphoric acid correspond to the following general formula (II):
O═P(OR′) 3−m (OH) m (II),
wherein
m represents the numbers 1 or 2, and
R′ represents a linear or branched C 1 -C 30 alkyl, acyl, C 2 -C 30 alkenyl, alkoxyalkyl, C 5 -C 14 cycloalkyl or aryl radical, which is optionally substituted, or a triorganosilyl or diorganoalkoxysilyl radical, and R′ can be the same or different within the molecule.
In one preferred embodiment of the present invention, phosphorus compound C) is an ester of orthophosphoric acid comprising at least one optionally substituted linear or branched C 4 -C 30 alkyl radical R′. Examples of esters of phosphoric acid C) according to the invention include primary and secondary esters of orthophosphoric acid and mixtures thereof, such as di-(2-ethylhexyl) phosphate, dihexadecyl phosphate, diisononyl phosphate, mono-isodecyl phosphate and mono-(2-ethylhexyl) phosphate. Component C) can also be an ester of polyphosphoric acid or a mixture of a plurality of esters of polyphosphoric acid. Salts of ortho- and polyphosphoric acid esters are also suitable, such as alkali metal salts for example.
The aminosilane compounds which are known in the art, of general structural formula (III)
are used as component D),
wherein
R″ represents a hydrogen atom, an aliphatic hydrocarbon radical comprising 1 to 4 carbon atoms, a trialkoxysilylpropyl group or an aminoethyl group, and n, X, Y, and Z have the meanings given above.
Examples of aminosilane compounds which can be used include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, N-aminoethyl-3-aminopropyltrimethoxysilane, N-aminoethyl-3-aminopropyltriethoxysilane, 3-aminopropyl-methyl-diethoxysilane, N,N-bis-trimethoxysilylpropyl-amine and N-aminoethyl-3-aminopropylmethyldimethoxysilane.
All organometallic catalysts which are known to promote silane polycondensation can be used as component E). In particular, these include compounds of tin and titanium. Examples of preferred tin compounds include dibutyltin dilaurate, dibutyltin diacetate and dioctyl tin maleate, tin(II) octoate and dibutyltin bis-acetoacetonate. Examples of preferred titanium compounds include alkyl titanates, such as tetraisopropyl titanate and tetrabutyl titanate, and chelated titanium compounds, such as diisobutyl-bis(ethylacetoacetate)-titanate. Dibutyltin bis-acetoacetonate is most preferably used as component E).
Additives and adjuvant substances F) in the sense of the present invention include: drying agents, light stabilisers, plasticisers, bonding agents other than those cited under D), thixotropy-imparting agents, pigments and fungicides.
Drying agents which are particularly suitable include alkoxysilyl compounds such as vinyltrimethoxysilane, methyltrimethoxysilane, i-butyltrimethoxysilane and hexadecyltrimethoxysilane. Examples of plasticisers include phthalic acid esters, adipic acid esters, alkylsulphonic acid esters of phenols and esters of phosphoric acid.
Examples of thixotropy-imparting agents include polyamides, hydrogenated derivatives of castor oil, and polyvinyl chloride. Epoxysilanes and/or mercaptosilanes can be used as bonding agents in addition to the compounds cited under D).
The polyurethane compositions according to the invention preferably consist of 30 to 80% by weight of component A), 10 to 50% by weight of component B), 0.5 to 5% by weight of component C), 0.5 to 3% by weight of component D), 0.02 to 1% by weight of component E), and of 0 to 40% by weight of component F).
The present invention also relates to a method of producing the polyurethane compositions which crosslink by condensation according to the invention, characterised in that components A), B), C), E), and optionally F), are mixed with the exclusion of moisture and are subsequently treated with component D).
The present invention also relates to the use of the polyurethane compositions which crosslink by condensation according to the invention as a sealing material, adhesive material or coating material.
The polyurethane compositions which crosslink by condensation according to the invention firstly exhibit rapid curing, with skin formation times between 15 and 120 minutes, and secondly exhibit outstanding stability on storage within the temperature range up to 60° C. The crosslinked polymers are distinguished by their excellent mechanical properties and outstanding adhesion, particularly by their wet adhesion to all conceivable substrates, such as metals, ceramics, plastics, masonry or concrete for example.
EXAMPLES
Example 1
Production of a Polyurethane Comprising Alkoxysilyl Terminal Groups
2000 g of a polyether diol with an OH number of 28, prepared by the propoxylation of propylene glycol and subsequent ethoxylation of the propoxylation product (PO/EO ratio 80:20) were prepolymerised with 155.4 g isophorone diisocyanate at 70° C. with the addition of 0.02 g dibutyltin dilaurate until the theoretical NCO content of 0.78% was reached. After cooling to 60° C., 140.4 g N-(3-trimethoxysilylpropyl)-aspartic acid diethyl ester (prepared according to EP-A 596 360, Example 5) were rapidly added drop-wise thereto, and the batch was stirred until the isocyanate band was no longer visible in the IR spectrum. The polyurethane prepolymer which was obtained, which comprised alkoxysilyl terminal groups, had a viscosity of 76,000 mPas (23° C.).
Example 2
Production of a Polyurethane Comprising Alkoxysilyl Terminal Groups
2000 g of a polyether diol with an OH number of 28, prepared by the propoxylation of propylene glycol and subsequent ethoxylation of the propoxylation product (PO/EO ratio 80:20) were prepolymerised with 155.4 g isophorone diisocyanate at 70° C. with the addition of 0.02 g dibutyltin dilaurate until the theoretical NCO content of 0.78% was reached. After cooling to 60° C., 102 g N-phenyl-3-aminopropyltrimethoxysilane were rapidly added drop-wise thereto, and the batch was stirred until the isocyanate band was no longer visible in the IR spectrum. The polyurethane prepolymer which was obtained, which comprised alkoxysilyl terminal groups, had a viscosity of 86,000 mPas (23° C.).
Example 3
Production of a Polyurethane Composition According to the Invention
The following components were processed in a commercially available planetary mixer to produce a ready-to-use sealing material.
36.4 parts by weight
polyurethane from Example 1
12.9 parts by weight
diisoundecyl phthalate (plasticiser)
0.02 parts by weight
dibutyltin bis-acetoacetonate (10% solution in
solvent naphtha ® 100)
1.50 parts by weight
vinyltrimethoxysilane
46.2 parts by weight
precipitated chalk (Type: Socal ® U1S2
manufactured by Solvay GmbH)
2.00 parts by weight
di-2-ethylhexyl phosphate
1.40 parts by weight
Disparlon ® NVG 8403 S (a thixotropy-
imparting agent manufactured by Kusumoto
Chem. Ltd.)
The mixture was dispersed for 10 minutes under a pressure of 100 mbar, whereupon the internal temperature rose to 60° C. 1.5 parts by weight N-aminoethyl-3-aminopropyl-trimethoxysilane were subsequently added and were incorporated by stirring for 10 minutes under a pressure of 100 mbar. The sealing material which was thus produced exhibited excellent stability, adhered to almost all substrates and cured with a skin formation time of 30 minutes.
The product was introduced into a commercially available cartridge and stored at 50° C. After a period of storage of 90 days, the product could still be processed without problems, and the properties of the product were unchanged.
Example 4
Production of a Polyurethane Composition According to the Invention
The following components were processed in a commercially available planetary mixer to produce a ready-to-use sealing material.
36.0 parts by weight
polyurethane from Example 2
12.6 parts by weight
diisoundecyl phthalate (plasticiser)
0.02 parts by weight
dibutyltin bis-acetoacetonate (10% solution in
solvent naphtha ® 100)
2.20 parts by weight
vinyltrimethoxysilane
45.68 parts by weight
precipitated chalk (Type: Socal ® U1S2
manufactured by Solvay GmbH)
2.5 parts by weight
mono-2-ethylhexyl phosphate
1.4 parts by weight
Cabosil ® TS 720 (a pyrogenic hydrated silica
manufactured by Cabot GmbH)
The mixture was dispersed for 10 minutes under a pressure of 100 mbar, whereupon the internal temperature rose to 60° C. 2.1 parts by weight N-aminoethyl-3-aminopropyl-trimethoxysilane were subsequently added and were incorporated by stirring for 10 minutes under a pressure of 100 mbar. The sealing material which was thus produced exhibited excellent stability, adhered to almost all substrates and cured with a skin formation time of 40 minutes.
The product was introduced into a commercially available cartridge and stored at 50° C. After a period of storage of 90 days, the product could still be processed without problems, and the properties of the product were unchanged.
Example 5
Example 3 was repeated, except that no di-2-ethylhexyl phosphate was added. The product was introduced into a commercially available cartridge and stored at 50° C. After a period of storage of 22 days, the product could not longer be pressed out of the cartridge and had gelled.
Example 6
Example 4 was repeated, except that no mono-2-ethylhexyl phosphate was added. The product was introduced into a commercially available cartridge and stored at 50° C. After a period of storage of 25 days, the product could not longer be pressed out of the cartridge and had gelled. | The invention relates to polyurethane materials, cross-linked by silane polycondensation, containing alkoxylsilane functional polyurethanes, alkaline fillers, phosphorous compounds aminosilanes, organometallic compounds and optionally additional auxiliary agents, to a method for their production and to the use thereof. | 2 |
CROSS REFERENCE
[0001] This application claims priority from a provisional patent application entitled “2-D to 3-D Video Conversion” filed on Oct. 3, 2013 and having an Application No. 61/886,602. Said application is incorporated herein by reference.
FIELD OF INVENTION
[0002] The disclosure relates to image conversion, and, more particularly, to a method and a device for two-dimensional to three-dimensional image conversion.
BACKGROUND
[0003] As three-dimensional (“3D”) display devices become more ubiquitous in consumer electronics (e.g., liquid crystal display screens, plasma screens, cellular phones, etc.), generating 3D content for display on the consumer electronics becomes a growing area of research and development. As such, various real-time two-dimensional (“2D”) to 3D image conversion technologies have been developed to obtain 3D content from existing 2D video content sources, such as DVD, Blu-Ray, and over-the-air broadcasting. However, the current technologies are not acceptable for long term usage due to their high computational complexity and/or unsatisfactory image quality.
[0004] Current techniques for 2D to 3D video conversion use frame to frame movement obtained from video content analysis to reconstruct 3D objects. Furthermore, motion vectors can be further combined with other disclosed techniques such as linear perspective and color-based segmentation to obtain a qualitative depth map. However, calculating motion vectors and semantic video content analysis significantly increase computational complexity. For the foregoing reasons, there is a need for new methods and apparatuses for 2D to 3D image conversion having less computational complexity and implementations costs.
SUMMARY OF INVENTION
[0005] Briefly, the disclosure relates to a method to convert two-dimensional (“2D”) image content into three-dimensional (“3D”) image content for display on a display device, comprising the steps of: analyzing the 2D image content for predefined indicators and generating a depth map for each of the predefined indicators; determining a combined depth map as a function of the generated depth maps; and generating the 3D image content for display on the display device as a function of the combined depth map.
DESCRIPTION OF THE DRAWINGS
[0006] The foregoing and other aspects of the disclosure can be better understood from the following detailed description of the embodiments when taken in conjunction with the accompanying drawings.
[0007] FIG. 1 illustrates a block diagram for a 2D to 3D image converter.
[0008] FIG. 2 illustrates a block diagram for a scene analyzer.
[0009] FIG. 3 illustrates a flow diagram for generating 3D image content from 2D image content.
[0010] FIG. 4 illustrates a block diagram to generate a depth-from-details depth map from 2D image content.
[0011] FIG. 5 illustrates a block diagram to generate a depth-from-color depth map from 2D image content.
[0012] FIG. 6 illustrates a block diagram to generate a depth-from-model depth map from 2D image content.
[0013] FIG. 7 illustrates a graph of an example of a depth model.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0014] In the following detailed description of the embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration of specific embodiments in which the disclosure may be practiced.
[0015] FIG. 1 illustrates a block diagram for a 2D to 3D image converter. A 2D to 3D image content converter can comprise a down scaling block 10 , a scene analyzer 12 , a up scaling block 14 , a depth post processing block 16 , a depth based rendering block 18 , boost 3d filters 20 and 22 , and a depth output block 24 . 2D image content (e.g., frame data) can be inputted to the down scaling block 10 to down scale the 2D image content by a predefined factor (e.g., 2, 4, 8, or another predefined number). The 2D image content can be formatted in a YUV color space, an RGB color space, a PMS color space, an NCS color space, a TSL color space, or other image color space. For this example, the 2D image content is formatted in the YUV color space and can be processed one frame at a time. Thus, 2D to 3D conversion can be performed in frame. It is understood that other color spaces can also be used in the present disclosure.
[0016] The downscaled 2D image content is inputted to the scene analyzer 12 to identify predefined indicators (e.g., areas, objects, colors, models, luma values, etc.) in the down scaled 2D image content. For instance, a predefined area, a predefined object, predefined color, a predefined model, predefined luma values, and/or other predefined indicators can be identified. Once identified, depth information for the 2D image content is generated as a function of the identified predefined indicators.
[0017] The depth information is then inputted to the up scaling block 14 to up scale the depth information into an original format size of the 2D image content. The up scaled depth information is inputted to the depth post processing block 16 . The depth post processing block 16 can apply an infinite impulse response (“IIR”) to the downscaled 2D image content for sharpening the depth information. A finite impulse response (or other filter) can be applied as well to provide flexibility and to meet performance needs. Next, the depth post processing block 16 outputs a left view, a left view depth information, a right view, and a right view depth information.
[0018] The left view and the left view depth information are inputted to the boost 3D filter 20 . The boost 3D filter 20 can boost (e.g., sharpen) the YUV left view, and output the boosted left view to the depth output block 24 . Also, the right view and the right view depth information are inputted to the boost 3D filter 22 . The boost 3D filter 22 can boost (e.g., sharpen) the YUV right view, and output the boosted right view to the depth output block 24 . The depth output block 24 can receive the boosted left view and the boosted right view, and output the 3D image content according to the type of output mode selected to fit the format of the display device.
[0019] It is understood that down scaling and up scaling can be optional components in the embodiment. Down scaling and up scaling can aid in reducing the computational complexity. However, a non-down scaled 2D image content can also be used in conjunction with the embodiment. Furthermore, post processing block and filtering blocks can also be optional components in the embodiment. The description of the down scaling, up scaling, post processing, and filtering of the embodiment is not meant to limit the invention to such specific embodiment.
[0020] FIG. 2 illustrates a block diagram for a scene analyzer. The scene analyzer 12 comprises a details analyzer 40 , a color analyzer 42 , a model analyzer 44 , a luma analyzer 46 , a blender 48 , and a normalizer 50 . It is understood by a person having ordinary skill in the art that a scene analyzer can comprise one or more analyzers for a predefine number of scene indicators. The blender 48 and the normalizer 50 can also be substituted by other components or omitted altogether. Therefore, the illustration in FIG. 2 is in no way meant to limit the disclosure.
[0021] Referring to FIG. 2 , the 2D image content can be inputted to each of the analyzers 40 - 46 . The details analyzer 40 detects any areas in the 2D image content that has image details, and then generates a depth-from-details depth map accordingly. The color analyzer 42 detects any areas in the 2D image content that has a predefined color, and then generates a depth-from-color depth map accordingly. The model analyzer 44 selects a scene model for the 2D image content, and then generates a depth-from-model depth map accordingly. The luma values analyzer 46 detects any areas in the 2D image that are above one or more predefined luma values, and then generates a depth-from-luma depth map accordingly.
[0022] The depth-from-details depth map, depth-from-color depth map, depth-from-model depth map, and depth-from-luma depth map are inputted to the blender 48 . The blender 48 can apply a weighting algorithm to the various maps to generate a blended depth map. The blended depth map is outputted to the normalizer 50 , which normalizes the blended depth map and outputs the normalized depth map as depth information.
[0023] FIG. 3 illustrates a flow diagram for generating 3D image content from 2D image content. 2D image content can be converted to 3D image content by analyzing the 2D image content to detect scene indicators 30 . Based on the detected scene indicators, a depth map for each of the scene indicators is generated. Next, a combined depth map can be determined as a function of the generated depth maps 32 . Lastly, the 3D image content can be generated as a function of the combined depth map 34 . The generated 3D image content can then be displayed on a 3D display device.
[0024] FIG. 4 illustrates a block diagram to generate a depth-from-details depth map from 2D image content. The details analyzer 40 comprises a horizontal edge detector 80 , a vertical edge detector 82 , a blender 84 , a low pass filter 86 , a second predefined filter 88 , and a clipping block 90 . The 2D image content can be inputted to the horizontal edge detector 80 and the vertical edge detector 82 . The horizontal edge detector 80 detects horizontal edges within the 2D image content. The vertical edge detector 82 detects vertical edges within the 2D image content. The detected horizontal and vertical edges can be weighted, and then blended by the blender 84 . For instance, the detected vertical edges can be weighted more heavily than the detected horizontal edges before being inputted to the blender 84 .
[0025] The blender 84 can then blend the detected edges, and output that blended data to the low pass filter 86 . The low pass filter 86 filters the blended data and outputs the filtered data to the second predefined filter 88 . The low pass filter 86 may not adequately provide a stable result. Thus, the second predefined filter 88 applies a stronger filter to the filtered data and outputs the further filtered data to the clipping block 90 , which clips the further filtered data to generate the depth-from-details depth map. The predefined filter 88 can be programmed to provide a certain filter level. In this manner, a user can select the certain filter level based on application requirements.
[0026] The details analyzer 40 can be programmed to apply a certain depth for areas in the 2D image content as a function of the sizes of the areas in the 2D image content and the amount of details of those areas. In particular, larger areas with a small amount of details can be set to the background in the 2D image content. Small areas with a great amount of details can be set to the foreground in the 2D image content. Other combinations and thresholds can also be used in accordance with the disclosure to define the amount of depth to assign to the areas of the 2D image content. For instance, large areas with green color can be classified in the background (e.g., trees), while small areas with little details (e.g., humans) can be classified in the foreground.
[0027] Areas of the 2D image content can be defined pixel by pixel using a raster-scan mode. The areas can also be defined by dividing the respective image content into small blocks of regions, and processing those areas/regions accordingly, rather than a pixel-by-pixel method. Based on the disclosure, there can also be other methods for defining areas of the 2D image content known to a person having ordinary skill in the art. Therefore, the above examples are not meant to be limiting.
[0028] The details analyzer 40 can also focus on details from one or more components of a color space. For instance, details can be recovered from the luma component of the YUV color space for the 2D image content. The horizontal edge detector 80 can apply a filter on the 2D image content to detect the horizontal edges. Likewise, the vertical edge detector 82 can apply another filter on the 2D image filter to detect the vertical edges.
[0029] FIG. 5 illustrates a block diagram to generate a depth-from-color depth map from 2D image content. The color analyzer 42 comprises a color space converter 100 , an objects detector 102 , a filter 104 , and a depth map generator 106 . The 2D image content is inputted to the color space converter 100 . The 2D image content can be in a first color space, e.g., the YUV color space, and may need to be converted to another color space, e.g., the RGB color space for detection of a predefined color. However, the color space converter 100 is optional since the 2D image content may already be in a certain format, e.g., the RGB color space, where color detection can be directly applied.
[0030] The converted 2D image content can be inputted to the objects detector 102 which detects objects, including areas and/or other predefined items, of a certain predefined color. The detected objects can then be filtered by the filter 104 . The filter 104 outputs the filtered objects to the depth map generator 106 , which generates a depth-from-color depth map based on the filtered objects.
[0031] The color analyzer 42 can be programmed to apply a certain depth for certain areas of the 2D image as a function of the size of the detected objects in the 2D image content, locations of the objects, and the color of those certain objects. For instance, if a detected object or area is located in a top half of the 2D image content and the color of that object is substantially blue, then that area can be considered part of the background of the 2D image content and assigned a depth accordingly. Also, large objects or areas with dark colors, e.g., black, dark blue, or other darker colors, can also be programmed to be assigned as the background with an associated depth. It is understood that other predefined sizes, locations, and/or colors of objects and/or areas can also be used to analyze various 2D image content. Based on the disclosure, other scenarios can be programmed depending on the application requirements.
[0032] FIG. 6 illustrates a block diagram to generate a depth-from-model depth map from 2D image content. The model analyzer 44 comprises a color space converter 120 , an objects detector 122 , a central points locator 124 , a reliability factor generator 126 , a depth model selector 128 , and a depth map generator 130 . The 2D image content is inputted to the color space converter 120 . The 2D image content can be in a first color space, e.g., the YUV color space, and may need to be converted to another color space, e.g., the RGB color space, for detection of another color. However, the color space converter 120 is optional since the 2D image content may already be in a certain format, e.g., the RGB color space, where color detection can be directly applied.
[0033] The converted 2D image content can be inputted to the objects detector 122 , which detects objects, including areas and other predefined items, of a certain predefined color. Based on those detected objects, a location map can be generated for the 2D image content of the locations that have the certain predefined color. Central points for that detected object can be determined by the central points locator 124 using the location map. For instance, a color histogram for the 2D image content along a vertical axis can be used to determine a central point vpx in the vertical axis, where
[0000] vpx=x, where hist_x(x)=max(hist_x(location map)). Equation [1]
[0000] Another color histogram for the 2D image content along the horizontal axis can be used to determine a central point vpy in the horizontal axis, where
[0000] vpy=y, y=max(hist_y(location map)). Equation [2]
[0000] Furthermore, a reliability factor generator 126 can determine a reliability factor sk_rel for the detected objects, where
[0000] sk_rel=min(max(max((max(hist_x(location map)/1024)−0.2)×4,(max(hist_y(location map)/2048)−0.3)*2),0),1). Equation [3]
[0034] Using Equations [1] and [2], a vanish point (vpx, vpy) can be defined. Ideally, the vanish point can be the peak distribution of the projection along the x-axis and along the y-axis. The vanish point is more reliable as the histogram is sharper.
[0035] The depth model selector 128 can receive the central points vpx and vpy and the reliability factor sk_rel. The depth model selector 128 selects a model based on the detected objects (e.g., the central points vpx and vpy) and the reliability factor. Once the model is selected, the selected model is outputted to the depth map generator 130 along with the 2D image content for generating the depth-from-model depth map.
[0036] FIG. 7 illustrates a graph of an example of a model. The depth model selector 128 can assign depths such that object(s) near or at the central points vpx and vpy have less depth than objects further away from the central points vpx and vpy. As such, an object near or at the central points vpx and vpy can appear to be closer to the viewer in relation to that object than other items in the 2D image content. Depth curves F n (x) and F m (y) can be respectively defined in a horizontal axis (e.g., x axis) and/or a vertical axis (e.g., y axis) of the 2D image content. The depth curves F(x) and F(y) can also be defined separately, where the final depth information for the 2D image is determined by summing the depth curves together.
[0037] For instance, referring to FIG. 7 , a depth curve F 1 (x) can be plotted using an x axis versus a depth axis to depict the amount of depth for objects along the x axis of the 2D image content. For x=C, a central point of a detected object, the central object can have no depth, i.e., depth=0. Based on Equations [1]-[3], point C can be found by
[0000] C=szx/ 2*(1− sk _rel)+ vpx*sk _rel, Equation [4]
[0000] where szx is the width of the horizontal size of the picture width. Peripheral points, where x=0 and x=P5, can have greater depth values, i.e., F 1 (0)=U and F 1 (P5)=D. Thus, objects of the 2D image content at or near the respective locations of x=0 and x=P5 can have more depth than objects near F 1 (C). Generally, the x value for P5 can be equal to the width size szx of the 2D image content, the width size of the respective detected object, or size of some other area of the 2D image content.
[0038] Similarly, a depth curve F 2 (y) can be plotted using the y axis versus a depth axis to depict the amount of depth for objects along the y axis of the 2D image content. The depth axis can correspond to the amount of depth to apply to objects at certain locations along the y axis.
[0039] Depth curves F( ) can be defined by piece-wise functions, and be controlled by three or more points, e.g., points C, U, and D. The central point C can be determined from Equation [4]. The point U can be associated with a pixel having a left or top position in the 2D image content. The point D can be associated with a pixel having right or bottom position in the 2D image content. Furthermore, the depth curve F( ) can be partitioned along its horizontal axis. For instance, x=P1 and x=P2 are within a region between x=P0 and x=C, where C−P2=P2−P1=P1−P0. Also, x=P3 and x=P4 are within a region between x=C and x=P5. The depth values of the depth curve for F 1 (P1), F 1 (P2), F 1 (P3) and F 1 (P4) can be respectively defined as UP1=U/2, UP2=U/6, UP3=D/2, and UP4=D/6. In order for the depth information to be continuous in a time domain, an IIR filter for points C, U, and D can be applied in the time domain, e.g., C′(t)=alpha*C(t)+(1−alpha)*C′(t−1) . . . etc.
[0040] While the disclosure has been described with reference to certain embodiments, it is to be understood that the disclosure is not limited to such embodiments. Rather, the disclosure should be understood and construed in its broadest meaning, as reflected by the following claims. Thus, these claims are to be understood as incorporating not only the apparatuses, methods, and systems described herein, but all those other and further alterations and modifications as would be apparent to those of ordinary skilled in the art. | A method to convert two-dimensional (“2D”) image content into three-dimensional (“3D”) image content for display on a display device, comprises the steps of: analyzing the 2D image content for predefined indicators and generating a depth map for each of the predefined indicators; determining a combined depth map as a function of the generated depth maps; and generating the 3D image content for display on the display device as a function of the combined depth map. | 6 |
FIELD
[0001] The present disclosure is directed to systems and methods for dynamic multimodal visual message prioritization.
BACKGROUND
[0002] Communication devices that handle multiple types of communications are increasingly common. Although the availability of multiple communication modes gives users great flexibility in conducting communications, managing multiple message types can be difficult.
[0003] For example, a typical smart phone supports various types of communications in addition to voice telephony. For example, email, text messaging, and messaging via social networks can be supported. Moreover, smart phones can provide indications to a user when voicemail messages are waiting to be accessed. Techniques for organizing or prioritizing messages have been developed. However, such techniques have typically not applied to multiple communication modes. For example, email systems commonly allow users to direct email messages to different mailboxes or folders, depending on characteristics of the received email. Other systems provide for grouping of messages having common themes. Still other techniques have presented content using a grid of tiles that can be refreshed individually. More particularly, the individual tiles illustrate different messages or information sources. However, there is no provision in such systems for intermingling messages of different types. Moreover, such techniques do not satisfactorily achieve the goal of providing a convenient and readily understood depiction of messages from multiple sources and the priority thereof.
SUMMARY
[0004] Systems and methods that provide a graphical indication of the relative priority or importance of messages associated with different communication modes are provided. More particularly, a user interface that provides a graphical view or depiction of messages directed to a user is provided. The graphical representation can include a depiction of messages that arranges the messages in a multidimensional format. Moreover, the location of a message within the graphical representation, and relative to other messages, can provide a ready indication to the user of the relative importance of the message.
[0005] In accordance with at least some embodiments of the present disclosure, the user interface presents an “archery target” design, in which the different concentric circles provide different locations in which to provide a visual indication of a message. The messages included within a particular ring can be of different message types. However, the messages within a particular ring can share a common classification as to priority or importance. Continuing the example of an archery target type embodiment, a user can identify messages as being more important the closer they are to the center of the target.
[0006] Systems in accordance with at least some embodiments of the present disclosure include a communication device. Moreover, the communication device can be capable of supporting multiple communication modes. In addition, the communication device includes a display capable of depicting information to a user visually. In particular, the display can present an indication of multiple messages to the user simultaneously. Moreover, the display can arrange the visual indicators of different messages such that the position of a visual indicator within the user interface indicates a classification or priority of the associated message. In accordance with still further embodiments, the user may provide user input through a facility of the communication device, to select a message indication, and to respond to, access, or otherwise interact with the related message.
[0007] Additional features and advantages of embodiments of the present disclosure will become more readily apparent from the following description, particularly when taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a block diagram depicting components of a system in accordance with embodiments of the present disclosure;
[0009] FIG. 2 is a block diagram depicting components of a communication endpoint in accordance with embodiments of the present disclosure;
[0010] FIG. 3 depicts a user interface in accordance with embodiments of the present disclosure; and
[0011] FIG. 4 is a flowchart depicting aspects of a method in accordance with embodiments of the present disclosure.
DETAILED DESCRIPTION
[0012] FIG. 1 is a block diagram depicting components of a communication system 100 in accordance with embodiments of the present disclosure. In general, the communication system 100 includes one or more communication servers 104 . The communication server 104 is interconnected to a multimodal communication device 108 via one or more communication networks 112 . A user 114 is associated with the multimodal communication device 108 . The system 100 also includes a variety of additional communication endpoints 116 , of various types, which can operate to engage in communications with the multimodal communication device 108 via one or more of the networks 112 , and/or the communication server 104 .
[0013] The communication server 104 can provide communication services to client devices, including but not limited to the multimodal communication device 108 . As an example, a communication server 104 may comprise an enterprise server that routes communications addressed to the multimodal communication device 108 when such device 108 is available, and/or stores such messages for later retrieval by the multimodal communication device 108 or an affiliated device of the user 114 . Accordingly, a communication server 104 may comprise a telephony server, an email server, a text messaging server, a multimedia server, a social media server, or the like. Moreover, a single communication server 104 can provide support to a multimodal communication device 108 with respect to a plurality of communication modes. As a further example, some or all of the communication servers 104 operating in support of a multimodal communication device 108 may support a single communication mode. Moreover, multiple communication servers 104 may operate in series. For example, a first communication server 104 may provide support to a multimodal communication device 108 for communications of various modes over a cellular network, which can be used to deliver voice telephony communications received from a second communication server 104 comprising a voice telephony server, email communications from a third communication server 104 comprising a mail server, and social network messages from a fourth communication server 104 comprising a social network server. In addition, different communication servers 104 or combinations of communication servers 104 may operate in connection with a multimodal communication device 108 at different times. For instance, a first communication server 104 may operate in connection with a first network 112 comprising a cellular telephony network to support voice communications, at the same time that a second communication server 104 in connection with a second network 112 comprising an IP data network supports email and other data transmitted across the IP network.
[0014] The multimodal communication device 108 generally supports multiple message types. In general, the messages are directed to or associated with the user 114 of the multimodal communication device 108 . In an exemplary embodiment, the multimodal communication endpoint 108 comprises a mobile communication device capable of wireless communications over one or more networks 112 . Accordingly, in an exemplary embodiment, a multimodal communication endpoint 108 is a smart phone. However, embodiments of the present disclosure can be used with any communication endpoint 108 capable of supporting multiple communication modes and of providing graphical user interface to a user, including static endpoints. Therefore, other examples of a multimodal communication endpoint 108 include a desktop computer, a laptop computer, a tablet computer, a set top box, or the like.
[0015] The different message endpoints 116 represent endpoints that may engage in communications with the multimodal communication device 108 . Accordingly, examples include short message service (SMS) 120 , multimedia messaging service (MMS) 124 , voice telephony 128 , email 132 , and social media 136 endpoints or sources. Such endpoints or sources 116 may comprise stand alone devices and/or multimodal devices. Such endpoints or sources 116 are also typically associated with a user, however this is not necessarily the case. For example, an endpoint 116 may comprise an automated device, such as an interactive voice response (IVR) system.
[0016] FIG. 2 is a block diagram depicting a multimodal communication endpoint 108 in accordance with embodiments of the present disclosure. The multimodal communication endpoint 108 includes a processor 204 capable of executing program instructions. The processor 204 can include any general purpose programmable processor or controller for executing application programming. Alternatively, the processor 204 may comprise a specially configured application specific integrated circuit (ASIC). The processor 204 generally functions to run programming code implementing various functions performed by the multimodal communication endpoint 108 . For example, the processor 204 can implement functions including the classification and display of message notifications or indications as described herein.
[0017] The multimodal communication endpoint 108 also generally includes memory 208 . The memory 208 can be used in connection with the execution of programming by the processor 204 , and for the temporary or long term storage of data or program instructions. For example, the memory 208 can provide for the storage of a priority display application 212 that classifies, determines a location within a display at which to present an indication of a message, and controls operation of the user interface as described herein. As additional examples, the memory 208 can provide storage for an email application 216 , an SMS/MMS application 220 , a social media application 224 , a telephony application 228 , a video telephony application 232 , a browser 236 , or other communication applications 240 . The memory 208 can include solid state memory that is resident, removable, and/or remote in nature, such as DRAM and SDRAM. Alternatively or in addition, the memory 208 can include magnetic, optical, or other storage devices. Moreover, the memory can include a plurality of discrete components of different types and/or a plurality of logical partitions.
[0018] In addition, the multimodal communication endpoint 108 includes one or more user input devices 244 , and one or more user output devices 248 . Examples of user input devices 244 include a keyboard, a numeric keypad, touch screen, microphone, and pointing device combined with a screen or other position encoder. In accordance with embodiments of the present invention, the user output includes a visual display 252 , such as but not limited to a liquid crystal display. Moreover, the display 252 may be capable of presenting two-dimensional and/or three-dimensional images. The display 252 may also be combined with a user input 244 to provide a touch screen display. Other examples of user output devices 248 include a speaker and indicator lamps.
[0019] A multimodal communication endpoint 108 also includes one or more communication interfaces 256 . In general, a communication interface 256 supports communications between the multimodal communication endpoint 108 and another endpoint or source 116 , and/or a communication server 104 , via a network 112 . Moreover, examples of communication interfaces 256 include both wire line and wireless interfaces. Accordingly, examples of communication interfaces 256 include a circuit switched or plain old telephony system, Ethernet, Wi-Fi, cellular telephony, satellite telephony, Bluetooth, or the like.
[0020] With reference now to FIG. 3 , a user interface 304 , such as can be presented by the display 252 of a multimodal communication endpoint 108 operating a priority display application 212 as described herein is depicted. In general, the user interface 304 provides a graphical depiction that includes a multidimensional framework or schema 308 for presenting a plurality of message indications 312 . Moreover, the multidimensional schema 308 may represent different classifications of message indications 312 . For example, as depicted in FIG. 3 , the schema 308 can comprise a plurality of concentric rings, where each ring is associated a different message classification. Alternatively or in addition, a relative classification or prioritization between individual message indications 312 can be provided. For example, a message indication 312 that is closer to the center of the concentric circles of the schema 308 indicates that the associated message is more important or has received a higher level classification than a message associated with a message indication 312 that is farther from the center of the schema 308 . In the exemplary schema 308 , the different bands created by the different concentric rings 316 represent different classification assignments of messages pending action by the user 114 . For instance, the center ring or circle 316 a can be reserved for indications associated with messages from the user's 114 workplace. The second ring 316 b can be associated with messages from the user's 114 family. The outer ring 316 c can contain indications 312 associated with messages from the user's 114 friends or other contacts. Indications of messages 312 outside of the outermost ring 316 c may be associated with messages from unidentified contacts. Accordingly, in this exemplary schema 308 , proximity to the center of the concentric rings 316 indicates a degree of importance or the classification rank assigned to a message associated with the indication 312 . Moreover, while relative position can indicate relative importance, the provision of graphical depictions of different classes can assist a user 114 in readily identifying the class assigned to a message associated with a message indication 312 . In accordance with still other embodiments, the schema 308 is not limited to two dimensions. For example, a display 252 capable of rendering three dimensions can be used. In such embodiments, the third dimension, for example represented by the relative apparent height of the message indication 312 from the background of the user interface 304 can indicate an urgency associated with a message represented by a message indication 312 . Alternatively or in addition, message indications 312 can be provided in different colors, fonts and the like, to provide additional information discriminating between associated messages to the user 114 .
[0021] The user interface 304 can also provide for controls that enable the user 114 to interact with or concerning messages associated with message indications 312 . For example, a spotlight or active area 320 can be provided to initiate actions and/or to indicate a current activity. Thus, in the illustrated example, the activation area 320 indicates that the multimodal communication endpoint 108 is currently engaged in a voice call with “Susan” 324 . The activation area 320 can also be used to facilitate the handling of messages associated with message indications 312 . For example, a user 114 can enter input, such as tapping and dragging a message indication 312 to the activation area 320 , in order to answer a message comprising a call, access a voicemail, read the text of a message and launch a reply to the message, and the like. Other controls 328 can also be provided, for example to initiate communications utilizing various modes without necessarily referencing a message associated with a message indication 312 .
[0022] With reference now to FIG. 4 , aspects of a method in accordance with embodiments of the present disclosure are depicted. Initially, at step 404 , a determination is made as to whether a message has been received with respect to a multimodal communication endpoint 108 . As used herein, the receipt of a message can include the notification that a message addressed or otherwise directed to the multimodal communication endpoint 108 is available. Accordingly, a message may be received in the form of a ring associated with a telephony call, a notification that an email, voicemail, or other data is available for retrieval from a communication server 104 , a text message is received, or the like. In general, the process idles at step 404 until a message has been received.
[0023] Once a message is received, a classification of the message is determined (step 408 ). For example, the priority display application 212 may operate to determine the classification of the message. Determining the classification of a message can include implementing a rules engine for providing an assignment of the message to a predefined classification, or to assign a classification or priority of the message relative to other messages pending handling by the user 114 . The classification can be assigned by the rules engine in various ways. For instance, a classification or priority may be assigned by some other entity of authority, such as the communication server 104 , or a sending device 116 . Alternatively or in addition, a classification or priority can be determined by information or metadata associated with the message. For instance, the name of the sender, domain of the sender, time of the message, content of the message, whether the message is from a human or non-human source or sender, or any other characteristic included in or associated with the message can be utilized in order to determine the classification assigned to the message by the priority display application 212 .
[0024] At step 412 , a location for the message indication 312 associated with the receipt of a message within the schema 308 is selected (step 412 ). For instance, where the schema 308 provides different distinct areas in which message indications 312 can be displayed, one of those areas can be selected by the priority display application 212 , in view of the determined classification, for presenting the message indication 312 . Moreover, where multiple message indications 312 are presented by a user interface 304 simultaneously, the priority display application 212 can also determine a position or location in which to present a particular message indication 312 , relative to other message indications 312 . For instance, the relative distance to the center of the schema 308 can provide a representation of a relative importance of a message associated with a message indication 312 . Proximity to different axes can also be used. For instance, proximity to a vertical axis that extends through the center of the schema 308 can be reserved for relatively more important message indications 312 . Moreover, in addition to a location, other aspects of the message indication 312 can be selected in order to indicate a classification or prioritization of a message. For example, a bright color, bold type, or other feature can be selected in view of the determined classification. The indication of the message 312 can then be presented at the selected location, and with any other selected attributes (step 416 ). At step 420 , a determination can be made as to whether operation of the priority display application 212 is to be continued. If operation is to be continued, the process can return to step 404 , to await receipt of an additional message or notification of a message. Alternatively, the process can end.
[0025] As can be appreciated by one of skill in the art after consideration of the present disclosure, methods and systems that facilitate the identification of messages requiring prioritized handling by a user 114 are provided. Although certain examples that include the use of multiple concentric circles have been discussed, other schemas 308 in accordance with embodiments of the present disclosure can be utilized. For instance, any graphically depicted topography, in which a relative location of a message indication 312 signifies relative importance of an associated message can be utilized. For example, the topography can be in the form of a map in which different locations or regions are utilized for message indications 312 having different determined classifications. A schema can also include regions, locations and/or rings that are reserved for message indications 312 associated with messages that are from a non-human source, such as automatic notifications. Accordingly, any schema 308 in which message indications 312 are presented in two or more dimensions can be utilized.
[0026] In addition, although embodiments in which a priority display application 212 is executed in a multimodal communication device 108 have been discussed, other configurations are possible. For example, a priority display application 212 can be executed by a communication server 104 , or other device or server on behalf of a multimodal communication endpoint 108 . Moreover, different users 114 can be associated with different rules engines and/or priority schemes that determine the presentation of message indications 312 by the priority display application 212 on a display 252 .
[0027] The foregoing discussion of the invention has been presented for purposes of illustration and description. Further, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings, within the skill or knowledge of the relevant art, are within the scope of the present invention. The embodiments described hereinabove are further intended to explain the best mode presently known of practicing the invention and to enable others skilled in the art to utilize the invention in such or in other embodiments and with various modifications required by the particular application or use of the invention. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art. | Methods and systems for providing a depiction of the relative importance of messages directed to a user of a multimodal communication endpoint are provided. More particularly, message indications are placed within a schema having two or more dimensions, depending on a determined classification or importance. Accordingly, the location, and optionally other attributes, of the message indication provides distinguishing characteristics that communicate a relative importance and/or relevance of a message to a user. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to novel underarm formulations which contain volatile and/or non-volatile alkylmethylsiloxanes of the structure (Me 2 SiO) a (MeRSiO) b or R'Me 2 SiO(Me 2 SiO) y (MeRSiO) z SiMe 2 R". wherein a is 0-5, b is 1-6, a+b is 3-6. y is 0-100, z is 0-100, and R, R' and R" are independently alkyls of 1-60 carbon atoms, with the proviso that at least one of R, R' or R" is an alkyl of 4-60 carbon atoms. The present invention also relates to novel underarm formulations which contain non-volatile aralkylmethylsiloxanes of the structure (Me 2 SiO) a (MeRSiO) b or R'Me 2 SiO(Me 2 SiO) y (MeRSiO) z SiMe 2 R", wherein a is 0-5, b is 1-6, a+b is 3-6, y is 0-100, z is 0-100, y+z≧1, and R, R' and R" are independently alkyls of 1-60 carbon atoms or aralkyls of 7-60 carbon atoms, with the proviso that at least one of R, R' or R" is an aralkyl of 7-60 carbon atoms. Incorporation of these compounds unexpectedly provides novel properties to the formulation.
Many underarm compositions are known in the art and described in the cosmetic literature. Such compositions often contain polyorganosiloxanes because of the desirable characteristics they impart. These characteristics include, for example, volatility without cooling, lubricity, and non-tacky delivery of the active agents. The siloxanes incorporated into these compositions, however, are generally limited to those with short alkyl groups such as dimethylpolysiloxanes.
The incorporation of other volatile siloxanes into antiperspirant formulations is also known in the art. For instance Bolich in U.S. Pat. No. 5,002,762 describes antiperspirant compositions incorporating siloxanes of the structure:
R.sub.3 SiO[R.sub.2 SiO].sub.x SiR.sub.3
wherein x=1 to 4, the total carbons ≦14, R is independently C1-C10 alkyl or trialkyl siloxy, and at least one R per molecule must be selected from aryl, alkylaryl, aryl alkyl, C1-C7 hydroxyalkyl, or R1-R2 wherein R1=C1-C9 alkylene and R2 is selected from a wide variety of substituents such as esters, amides, acids, cyanos, etc. Since these materials have a limited number of carbon atoms and contain the above R groups, they do not encompass the materials claimed in the present invention.
Various utilities for alkylmethylsiloxane polymers and copolymers are also known in the art. For instance, Th. Goldschmidt AG product literature on "ABIL® Silicones" reports that certain polysiloxane polyalkylene copolymers known as ABIL®-WAX 9800 and ABIL®-WAX 9801 have utility in skin care applications such as day creams, all purpose creams and body lotions. This literature, however, does not suggest the use of these agents in underarm formulations.
Similarly. U.S. Pat. No. 4,574,082 issued Mar. 4, 1986 describes cosmetics containing a dimethylpolysiloxane in admixture with an organopolysiloxane such as polymethyloctylsiloxane and polymethyloctadecylsiloxane. It is described therein that such mixtures inhibit the phase separation which occurs when waxes are mixed with dimethylsiloxanes. Again, however, this reference does not describe the use of these agents in underarm formulations.
What was not described in the prior art, therefore, is the incorporation of the presently claimed alkylmethylsiloxanes into underarm formulations. The present inventors have now discovered that underarm formulations containing such agents have many desirable characteristics such as modified hardness, reduced whitening, improved feel, compatibilization of ingredients, and controlled vapor pressure.
SUMMARY OF THE INVENTION
The present invention is directed to underarm formulations which contain volatile and/or non volatile alkylmethylsiloxanes of the structure (Me 2 SiO) a (MeRSiO) b or R'Me 2 SiO(Me 2 SiO) y (MeRSiO) z SiMe 2 R", wherein a is 0-5, b is 1-6, a+b is 3-6, y is 0-100, z is 0-100, and R, R' and R" are independently alkyls of 1-60 carbon atoms, with the proviso that at least one of R, R' or R" is an alkyl of 4-60 carbon atoms. The present invention also relates to novel underarm formulations which contain non-volatile aralkylmethylsiloxanes of the structure (Me 2 SiO) a (MeRSiO) b or R'Me 2 SiO(Me 2 SiO) y (MeRSiO) z SiMe 2 R", wherein a is 0-5, b is 1-6, a+b is 3-6, y is 0-100, z is 0-100, y+z≧1, and R, R' and R" are independently alkyls of 1- 60 carbon atoms or aralkyls of 7-60 carbon atoms, with the proviso that at least one of R, R' or R" is an aralkyl of 7-60 carbon atoms. These formulations may contain other components such as astringent antiperspirant compounds, antimicrobial actives, adsorbents, absorbents, conventional volatile silicones, suspending agents, conventional waxes, emollients, perfumes, coloring agents, and other ingredients normally used in making underarm products.
These and other features, objects and advantages of the present invention will be apparent upon consideration of the following detailed description of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is based on the unexpected discovery that the incorporation of alkylmethylsiloxanes into underarm formulations adds novel properties thereto. Such novel underarm formulations can include, for example, antiperspirant and/or deodorant formulations and the like.
Conventional underarm products often contain numerous ingredients depending on factors such as the utility of the product, the final product form (i.e., solid, liquid, gel, etc.), the desired physical properties, etc. These ingredients include, for example, astringent antiperspirant compounds, antimicrobials, volatile silicones, suspending agents, waxes, adsorbents, emollients, perfumes, coloring agents, and the like. The novel formulations of the present invention have some or all of the above volatile silicones, emollients and/or waxes of the conventional formulations replaced with alkylmethylsiloxanes.
As set forth above, volatile silicones are often added to underarm formulations because of the beneficial properties they impart such as volatility without cooling, lubricity, and non-tacky delivery of the actives. The present inventors have now discovered that additional beneficial properties can be obtained by replacing some or all of these conventional volatile silicones with volatile alkylmethylsiloxanes. For instance, alkylmethylsiloxanes have lower vapor pressures than conventional dimethylsiloxanes. As such, the vapor pressure of a formulation can be tailored to regulate its drying time or to control its release of volatiles (for regulatory purposes). Volatile alkylmethylsiloxanes also vary the aesthetics of underarm formulations by providing a more lubricous feel than conventional formulations. Moreover, alkylmethylsiloxane increase the payout of underarm formulations such that tailored delivery of active agents can be achieved. Finally, since alkylmethylsiloxanes have a structure which contains both inorganic linkages and long carbon chains, they aid in compatibilizing the array of ingredients often contained in underarm formulations.
As noted above, conventional underarm formulations (especially sticks) also often contain waxy materials to provide a structure which can be sheared when applied to the skin. Conventional waxes have melting points in the range of about 30° to about 150° C. and can include materials such as beeswax, spermaceti, carnauba, bayberry, candelilla, montan, ozokerite, ceresin, paraffin, microcrystalline wax, fatty acids with 8-20 carbon atoms, fatty alcohols containing from about 8 to about 30 carbon atoms, and fatty acid ester such as hydrogenated castor oil. Such waxes, however, often suffer from various disadvantages such as variability in hardness, a crystalline structure which causes them to crumble upon application, difficulties in obtaining and processing the materials, and the like. By replacing some or all of these waxes with alkylmethylsiloxanes, many of these disadvantages can be avoided. For instance, various physical properties of a formulation such as its melting point, hardness and texture can be tailored by altering the structure of the alkylmethylsiloxane. Likewise, the alkylmethylsiloxanes provide various processing advantages such as reproducible melt viscosity, better setting performance, and decreased surface tension because they can be produced in a purer form than the mixtures contained in naturally occurring waxes. In addition, since the alkylmethylsiloxanes are synthetic, they are generally more readily available than natural products. Finally, though the mechanism is unclear, incorporation of alkylmethylsiloxanes into underarm formulations also surprisingly reduces whitening of such formulations and, thus, provides improved aesthetics which are desired by consumers.
Additional non-volatile liquid siloxanes can also be incorporated into underarm formations. These can be used, for example, to replace or supplement conventional emollients and thereby provide formulations with a smoother feel.
Thus, underarm formulations with the above properties can be obtained by incorporating volatile and/or non-volatile alkylmethylsiloxanes of the structure
(Me.sub.2 SiO).sub.a (MeRSiO).sub.b or
R'Me.sub.2 SiO(Me.sub.2 SiO).sub.y (MeRSiO).sub.z SiMe.sub.2 R",
wherein a is 0-5, b is 1-6, a+b is 3-6, y is 0-100, z is 0-100, R, R' and R" are independently alkyls of 1-60 carbon atoms, with the proviso that at least 1 of R, R' and R" is an alkyl of 4-60 carbon atoms, preferably 6-60 carbon atoms. Alternatively, the non-volatile aralkylmethylsiloxane can have the above structure wherein a is 0-5, b is 1-6, a+b is 3-6, y is 0 100, z is 0-100, y+z≧1,. and R, R' and R" are independently alkyls of 1-60 carbon atoms or aralkyls of 7-60 carbon atoms, with the proviso that at least one of R, R' or R" is an aralkyl of 7-60 carbon atoms. As is readily apparent to those skilled in the art, some of the above compounds are volatile and others are non-volatile liquids or waxes at room temperature. As such, one skilled in the art would know which materials may be used as volatile components and those which may be used as non-volatile components in underarm formulations. As used herein, the term "volatile" is used to describe those materials which have a vapor pressure of at least 0.01 mm Hg at 22° C.
Examples of non-volatile materials which are useful herein include liquids such as [C 6 H 13 MeSiO] 4 , Me 3 SiO[Me 2 SiO] 3 [MeSiCH2CHMePhO] 6 SiMe 3 , Me 3 SiO[Me 2 SiO] 95 [MeC 6 H 13 SiO] 5 SiMe 3 , or Me 3 SiO[Me 2 SiO] 60 [MeC 6 H 13 SiO] 40 SiMe 3 , and waxes such as [C 14 H 29 MeSiO] 4 , [C 20 H 41 MeSiO] 5 , Me 3 SiO[Me 2 SiO] 3 [MeC 18 H 37 SiO] 5 SiMe 3 , Me 3 SiO[Me 2 SiO] 3 [MeC 24 H 49 SiO] 5 SiMe 3 , Me 3 SiO[Me 2 SiO] 70 [MeC 30 H 61 SiO] 30 SiMe 3 , C 18 H 37 Me 2 SiO(Me 2 SiO) 12 SiMe 2 C 18 H 37 , C 24 H 49 Me 2 SiO(Me 2 SiO) 12 SiMe 2 C 24 H 49 , and Me 3 SiO[MeC 18 H 37 SiO] 10 SiMe 3 .
Examples of volatile materials include Me 3 SiOSiMe 2 C 3 H 7 , Me 3 SiOSiMe 2 C 6 H 13 , [C 2 H 5 MeSiO]4, [C 6 H 13 MeSiO]4, 8 C 2 H 5 MeSiO] 5 , and [C 2 H 5 MeSiO] 3 .
The above alkylmethylsiloxanes are known in the art and can be produced by known methods. For example, cyclic alkylmethylsiloxane polymers can be produced by the reaction of cyclic siloxanes having Si--H functional units thereon (e.g., [MeHSiO] a ) with a slight stoichiometric excess of an alkene in the presence of a platinum on carbon catalyst. Likewise, linear and cyclic alkylmethyl-dimethyl copolymers can be produced by the reaction of linear siloxanes having Si--H functionality in their chains (such as (Me 3 SiO 0 .5) 2 (MeHSiO) x , in which x is about 4-100) with cyclic siloxanes having (Me 2 SiO) x units, in which x is 3-6. The reaction product (generally about 10% cyclic and 90% linear) is then contacted with a slight stoichiometric excess of an alkene in the presence of a platinum on carbon catalyst.
Batch production of the alkylmethylsiloxanes is conducted by adding the reaction product to a non-agitated suspension of the catalyst in the alkene at about sixty degrees Celsius. Continuous production of the alkylmethylsiloxanes is conducted by pumping a preheated solution of a stoichiometric excess of an alkene CH 2 ═CHR and the siloxane having SiH functional units through a packed column containing platinum on carbon catalyst chips. The column will require provision for the removal of heat because of the exothermic nature of the reaction.
The materials are further processed in accordance with the present invention in order to provide a more cosmetically acceptable product by removing from the product any residual reactants and or by-products. The alkylmethyl polysiloxanes produced in accordance with the present invention have been found to contain at most about 0.5 percent residual alkene and about 99.5 percent alkylmethyl polysiloxane product. No measurable residual amount of platinum has been detected. The products are colorless, odorless, non-volatile, clear and stable materials.
In addition to the above alkylmethylsiloxanes, the underarm formulations of the present invention can also contain other conventional ingredients. These can include, for example, astringent antiperspirant compounds, antimicrobials adsorbents, absorbants, conventional volatile silicones, suspending agents, conventional waxes, emollients, perfumes, coloring agents, and the like.
Any conventional astringent antiperspirant compound can be used in accordance with the present invention. In general such materials comprise inorganic and organic salts of aluminum, zirconium, and zinc and mixtures thereof. Representative compounds are described throughout the patent literature in U.S. Pat. No. 4,280,994 issued Jul. 28, 1981: U.S. Pat. No. 4,369,173 issued Jan. 18, 1983; U.S. Pat. No. 4,425,328 issued Jan. 10 1984; U.S. Pat. No. 4,725,432 issued Feb. 16, 1988, and U.S. Pat. No. 4,822,603 issued Apr. 18 1989. Examples of such astringent antiperspirant compounds are aluminum chloride, aluminum chlorohydrate, aluminum dichlorohydrate, aluminum-zirconium chlorohydrate, aluminum chlorohydrex, aluminum-zirconium trichlorohydrate, aluminum-zirconium pentachlorohydrate, aluminum-zirconium tetrachlorohydrex glycine, aluminum-zirconium octachlorohydrate, aluminum sesquichlorohydrate, aluminum sulfate, zinc sulfate, zirconium chlorohydrate, aluminum-zirconium chlorohydroglycine, zirconium hydroxychloride, sodium aluminum lactate, sodium aluminum chlorohydroxy lactate, zinc sulfocarbolate, aluminum bromide, zinc phenolsulfonate aluminum sulfate and aluminum bromohydrate. In addition, it is contemplated that the above antiperspirants may be coated by techniques known in the art such as that described in U.S. Pat. No. 4,524,062, granted Jun. 18. 1985.
Conventional volatile silicones may also be used in the present invention. Generally such silicones comprise cyclic and linear polyalkyl siloxanes of the structures [Me 2 SiO] x and (Me 3 SiO) 2 [Me 2 SiO] y respectively, wherein x is 3 to 7, y is 1 to 5, and Me is methyl. Such materials generally have viscosities less than about 10 centistokes and have a measurable vapor pressure.
Conventional waxy materials which may be employed in accordance with the present invention include high and low melting point waxes, gums, resins, polymers, starches and elastomers. Exemplary high melting point waxes are insect and animal waxes such as beeswax and spermaceti; vegetable waxes such as candelilla, carnauba, Japan wax, Ouricury, Douglas-fir bark wax, rice-bran wax, jojoba wax, castor wax and bayberry wax; mineral waxes such as montan wax, peat wax, ozokerite and ceresin; petroleum waxes such as paraffin wax; synthetic waxes such as polyethylene waxes, Fischer-Tropsch waxes, chemically modified hydrocarbon waxes and substituted amide waxes; and conventional silicone wax. A particularly preferred high melting point wax is hydrogenated castor oil. Reference may be had to U.S. Pat. No. 3,395,941 issued Jul. 30, 1968 describing a silicone wax which is an organosilicon block copolymer; and U.S. Pat. No. 3,563,941 issued Feb. 16, 1971 describing a silicone-carnauba wax copolymer. Examples of low melting point waxes include fatty acids, fatty alcohols, fatty acid esters, and fatty acid amides having carbon chains of 3 to 30 carbon atoms. Particularly preferred low melting point waxes include stearyl alcohol, cetyl alcohol, myristyl alcohol and palmitic acid. U.S. Pat. No. 4,822,603, issued Apr. 18, 1989 describes many of these materials in detail.
The present invention may also contain fillers, suspending agents and other particulate material. These include, for example, talc, colloidal silica, clays and the like. Such materials are well known in the art and described in the literature.
Emollients, perfumes, colorants, emulsifiers and other ingredients normally used in making underarm products may also be used herein. Such materials are well known in the art and are described throughout the patent literature such as in U.S. Pat. Nos. 4,280,994: 4,425,328: 4,725,432; and 4,822,603.
The above ingredients are processed by conventional techniques to form the desired product. Using such techniques, gels, roll-ons, aerosols, pump sprays, and solid sticks may all be formed herein. If a solid stick is desired, is can be formed, for instance, by heating any wax materials while gently stirring. When the wax or waxes are melted and mixed thoroughly, any additional ingredients are added. The melt is then poured into a desired mold and allowed to cool to its solidification point. Alternatively, the above melt may be cooled and the additional ingredients added at a temperature just above the solidification point followed by pouring the mixture into a mold. In still another method, all of the ingredients are combined and heated above the melting point of the waxes. The composition is then cooled and poured into molds. If a liquid is desired (e.g., for roll-ons and sprays), it can be obtained by simply dissolving or dispersing the solids in solvents or liquids (e.g., alcohols).
The ingredients and amounts thereof to be included in the present invention are selected to produce the desired formulation. Generally, if a wax is to be included (e.g., for a stick), it is generally present in an amount of from about 0.5 to about 50% by weight. Active antiperspirant compounds are generally present in formulations in an amount of between about 3 and about 70% by weight. The total volatile silicone content of such formulations is generally in the range of between about 5 and about 80% by weight. Additional ingredients are added make up the remainder of the desired product form.
The formulations of the present invention are used in the conventional manner by topically applying an effective amount of the composition to areas of the body prone to perspiration.
The following examples are set forth in order to illustrate formulations prepared in accordance with the present invention.
EXAMPLE 1
In this Example, 8 antiperspirant sticks were produced having the following generic formulation:
______________________________________1) [Me.sub.2 SiO].sub.5 -Me.sub.2 SiO].sub.6 mixture 42%2) Alkylmethylsiloxane 10%3) Stearyl Alcohol 20%4) Hydrogenated Castor Oil 4%5) PEG-8 Distearate 2%6) Aluminum Zirconium 20% Tetrachlorohydrex-Gly______________________________________
In addition, a control stick was made containing no alkylmethylsiloxane and 52% of ingredient #1.
The above sticks were made by charging a container equipped for reflux with ingredients 1-5. This mixture was heated to 75° C. and stirred until all of the solids had dissolved. Ingredient 6 was added to the mixture and uniformly dispersed by stirring. The mixture was then slowly cooled to about 46° C. and cast into the stick containers.
The following table lists several characteristics of the sticks. The alkylmethylsiloxanes used therein were as follows: 1═Me 3 SiO[Me 2 SiO] 95 [MeC 6 H 13 SiO] 5 SiMe 3 , 2═Me 3 SiO[Me 2 SiO] 7 [MeC 6 H 13 SiO] 1 SiMe 3 , 3═Me 3 SiO[Me 2 SiO] 60 [MeC 6 H 13 SiO] 40 SiMe 3 , 4═C 18 H 37 Me 2 SiO(Me 2 SiO) 12 SiMe 2 C 18 H 37 , 5═C 24 H 49 Me 2 SiO(Me 2 SiO) 12 SiMe 2 C 24 H 49 , 6═C 30 H 61 Me 2 SiO(Me 2 SiO) 12 SiMe 2 C 30 H 61 , 7═Me 3 SiO[Me 2 SiO] 60 [MeC 18 H 37 SiO] 40 SiMe 3 , and 8═Me 3 SiO[MeC 18 H 37 SiO] 10 SiMe 3 .
TABLE 1______________________________________ Com-Ex Form patible Cavitation Penetration WhiteNo (1) Mw (2) (3) (4) (5)______________________________________C.sup.6 -- -- Y M M 41 L 7912 N L H 42 L 824 N L M 33 L 10362 N L L 34 L 1526 Y H M 25 S 1694 Y M M 16 S 1862 Y M M 17 S 17082 Y L M 18 S 3282 Y L L 1______________________________________ (1) Form of the alkylmethylsiloxane L = liquid, S = solid (2) Compatibility of melt N = no, Y = yes (3) Cavitation or shrinkage of the stick on cooling H = statistically higher than the control stick, M = statistically the same as the control stick and L = statistically lower than the control stick (4) Penetration = hardness of the stick H, M, and L have the same definition as in #3 (5) White = amount of whitening from the stick when applied to a black ceramic tile 1 = least white 4 = most white (6) Control stick
EXAMPLE 2
In this Example, antiperspirant sticks having the following formulations were produced:
______________________________________ Control A B______________________________________1) Me.sub.3 SiOSiMeC.sub.6 H.sub.13 OSiMe.sub.3 -- 52% 26%2) [Me.sub.2 SiO].sub.5 -Me.sub.2 SiO].sub.6 mixture 52% -- 26%3) Stearyl Alcohol 20% 20% 20%4) Hydrogenated Castor Oil 4% 4% 4%5) PEG-8 Distearate 4% 4% 4%6) Aluminum Zirconium 20% 20% 20%Tetrachlorohydrex-Gly______________________________________
The above sticks were made by charging a container equipped for reflux with ingredients 1-5. This mixture was heated to 70° C. and stirred until all of the solids have dissolved. Ingredient 6 was added to the mixture and uniformly dispersed by stirring. The mixture was then slowly cooled to about 45° C. and cast into the stick containers.
The sticks of the present invention had a more lubricous feel than that of the control and they maintained this feel for a longer period of time.
EXAMPLE 3
In this Example, 4 antiperspirant roll-ons were produced having the following formulations:
______________________________________ Con- trol A B C______________________________________1) [Me.sub.2 SiO].sub.5 -Me.sub.2 SiO].sub.6 mixture 70% -- 35% 70%2) Volatile Alkylmethyl- -- 70% 35% -- siloxane(1)3) Non-volatile Alkylmethyl- -- -- -- 5% siloxane(2)4) Dimethylpolysiloxane 5% 5% 5% 5% fluid, 50 cst5) Bentone V55 gel ® 3% 3% 3% 3% (Rheox Co.)6) Ethanol 95 2% 2% 2% 2%7) Aluminum Zirconium 20% 20% 20% 20% Tetrachlorohydrex-Gly______________________________________
The above roll-ons were made by charging a container equipped for reflux with ingredients 1, 2, 5 and 6 followed by mixing to swell/disperse the clay. Ingredients 3, 4, and 7 were then added and uniformly dispersed. The mixture was then poured into appropriate roll-on containers.
The roll-ons of the invention had less whitening than the control.
EXAMPLE 4
In this Example, 2 antiperspirant pump sprays were produced having the following formulations:
______________________________________ A B______________________________________1) Aluminum chloride hydroxide 23.4% 23.4%2) Ethanol 95% 54.6% 54.6%3) Propylene Glycol 3 Myristyl Ether 10.0% 10.0%4) Stearic Acid 2.0% 2.0%5) [SiMe.sub.2 O].sub.5 10.0% --6) Volatile Alkylmethylsiloxane Fluid -- 10.0%______________________________________
The ingredients were added to a container in the order listed --each ingredient being dissolved before adding the next. Both resultant formulations were clean. Formulation B was less cooling upon drying and less whitening on the skin.
EXAMPLE 5
In this Example, 4 antiperspirant sticks were produced having the following formulations:
______________________________________ Control A B C______________________________________1) [Me.sub.2 SiO].sub.5 -Me.sub.2 SiO].sub.6 mixture 55% 55% 55% 55%2) Stearyl Alcohol 20% 20% 20% 20%3) Castor Wax MP80 1% -- -- --4) Alkylmethylsiloxane wax -- 1% 1% 1%5) PPG-14 Butyl Ether 2% 2% 2% 2%6) Talc 2% 2% 2% 2%7) Aluminum Zirconium 20% 20% 20% 20% Tetrachlorohydrex-Gly______________________________________
The alkylmethylsiloxane waxes were as follows: A═Me 3 SiO[MeC 30 H 61 SiO]SiMe 3 , B═C 30 H 61 Me 2 SiO[Me 2 SiO] 12 SiMe 2 C 30 H 61 and C═[MeSiC 30 H 61 O] 4
The above sticks were made by charging a container equipped for reflux with ingredients 1-6. This mixture was heated to 75° C. and stirred until all of the solids had dissolved. Ingredient 7 was added to the mixture and uniformly dispersed by stirring. The mixture was then slowly cooled to about 46° C. and cast into the stick containers.
The sticks of the present invention (A, B, and C) had a more lubricous feel and the perception lasted longer than that of the control. In addition, the sticks of the present invention were softer and had reduced whitening when compared with the control. | This invention relates to an underarm formulation containing volatile and/or non-volatile alkylmethylsiloxanes. Incorporation of such agents results in formulations which have beneficial effects such as decreased whitening, less crumbling, better compatibility, controlled vapor pressure and better aesthetics. In addition, use of these materials often results in processing advantages over the prior art. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to compressors that perform compression by rotating a rotary shaft with the power of an external drive source, and more particularly, to a sealing structure that seals about the rotary shaft to prevent fluids such as refrigerant and lubricating oil in the compressor interior, or high pressure zone, from leaking out to the compressor exterior, or low pressure zone.
Japanese Unexamined Patent Publication No. 6-300142 discloses an example of a sealing apparatus incorporated in a compressor to seal about a rotary shaft of the compressor. As shown in FIG. 7, the sealing apparatus is provided with a rubber first lip ring 91 and a second fluororesin second lip ring 2, which is arranged toward the outer side of the compressor with respect to the first lip ring 91. The first lip ring 91 and the second lip ring 92 respectively have lip portions 911, 921 that contact the outer surface 931 of a rotary shaft 93 to prevent leakage of fluid when the rotary shaft 93 is rotated or stopped.
The lip portion 911 of the first lip ring 91 permits leakage of fluid toward the second lip ring 92 during rotation of the rotary shaft 93. The fluid leaking from the lip portion 911 (mainly lubricating oil) lubricates the lip portions 911, 921 to prevent frictional deterioration and thermal deterioration caused by high temperatures. This increases the durability of the lip portions 911, 921.
It is significant that the contacting posture of the lip portion 911 with respect to the peripheral surface 931 of the rotary shaft 93 be set and maintained at an optimal state to prevent the leakage of fluid when stopping the rotation of the rotary shaft 93 while permitting leakage when rotating the rotary shaft 93, as described above. In the sealing apparatus of the above publication, the second lip ring 92 is adhered to the first lip ring 91. The contacting posture of the lip portion 911 with respect to the peripheral surface 931 of the rotary shaft 93 is maintained by the support of the second lip ring 92.
However, when the pressure in the compressor becomes high, the first lip ring 91, which is urged by the force of the high pressure, presses the lip portion 921 against the rotary shaft 93 with excessive force. This raises the temperature of the lip portion 921 and the temperature about the lip portion 921. As a result, the heated lip portion 921 affects the rubber lip portion 911, which has inferior heat resistance in comparison to fluororesin, and causes thermal deterioration.
Accordingly, it is an objective of the present invention to provide a compressor sealing structure that suppresses the deterioration of the lip portion of the first lip ring and that has superior durability.
SUMMARY OF THE INVENTION
In the sealing apparatus according to the present invention, a posture maintaining member is arranged between a first lip ring and a second lip ring to support a contacting posture of a lip portion of a first lip ring with respect to the outer surface of the rotary shaft. In this manner, the contacting posture of the lip portion of the first lip ring is maintained by an exclusive posture maintaining member. Accordingly, when the pressure in a crank chamber is high, the first lip ring is prevented from pressing a lip portion of the second lip ring against the outer surface of the rotary shaft with excessive force. As a result, excessive heating of the lip portion of the second lip ring is prevented. Thus, thermal deterioration that would be caused by the heating is prevented.
The contacting posture of the lip portion of the first lip ring with respect to the outer surface of the rotary shaft is arranged so that fluid does not leak toward the second lip ring during rotation of the rotary shaft. Accordingly, the fluid leakage optimally lubricates the lip portions of the first lip ring and the second lip ring and prevents frictional deterioration and thermal deterioration of the lip portion.
The lip portion of the first lip ring has a distal portion that includes an acute flare projecting in a radially inward direction. The lip portion of the first lip ring contacts the outer surface of the rotary shaft along an annular region of the outer surface with a distal end of the flare. The contacting posture of the lip portion of the first lip ring with respect to the outer surface of the rotary shaft is arranged so that an angle of an inclined surface defining the inner side of the flare with respect to the outer surface of the rotary shaft is smaller than an angle of an inclined surface defining the outer side of the flare with respect to the outer surface of the rotary shaft. Accordingly, the lip portion of the first lip ring is provided with sufficient sealing capability when the rotation of the rotary shaft is stopped and permits leakage of a large amount of fluid when the rotary shaft is rotated. As a result, the lubrication of the first lip ring and the second lip ring with the fluid leakage is satisfactory. This effectively prevents frictional deterioration and thermal deterioration of the lip portion.
Space is provided between the posture maintaining member and the lip portion of the second lip ring. Accordingly, when the pressure in the crank chamber is high, the load acting on the first lip ring is received by the posture maintaining member and not transmitted to the lip portion of the second lip ring. As a result, heating of the lip portion of the second lip ring is suppressed.
A pump structure actuated by the rotation of the rotary shaft is provided in a contact zone between the lip portion of the second lip ring and the outer surface of the rotary shaft. The pump structure forces fluid in the contact zone between the lip portion of the second lip ring and the outer surface of the rotary shaft toward the inside of the compressor. Accordingly, the sealing capability of the lip portion of the second lip ring is enhanced. As a result, the sealing capability of the entire sealing apparatus is not degraded despite the fact that the structure is such that fluid leaks from the lip portion of the first lip ring during rotation of the rotary shaft.
The pump structure includes a pump groove defined in at least one of the lip portion of the second lip ring and the outer surface of the rotary shaft. The pump groove is provided only in a section located toward the inside of the compressor in the contact zone between the lip portion of the second lip ring and the outer surface of the rotary shaft and not in a section located toward the outside of the compressor. That is, the pump groove is arranged so that it is not opened toward the outside of the compressor. Accordingly, the residual fluid in the pump groove does not flow out of the compressor when the rotation of the rotary shaft is stopped. As a result, the sealing capability of the sealing structure when the rotation of the rotary shaft is stopped is enhanced.
The pump groove extends spirally about the axis of the second lip ring. Accordingly, a spiral pump effect is produced between the pump groove and the outer surface of the rotary shaft during rotation of the rotary shaft.
The compressor includes a crank chamber and a cylinder bore that function as the inside of the compressor. A cam plate accommodated in the crank chamber is integrally rotatable with the rotary shaft and is inclinable. A piston is reciprocally accommodated in the cylinder bore. The pressure of the crank chamber is altered to change the difference between the pressure of the crank chamber and the pressure of the cylinder bore and vary the inclination of the cam plate to control displacement. Accordingly, the pressure of the crank chamber becomes high to minimize displacement. The advantages of the above sealing structure are effectively obtained, especially when applied to a compressor that withstands such harsh conditions.
The compressor is provided with a refrigerant circulation impeding means for impeding the circulation of refrigerant in an external refrigerant circuit in cooperation with a minimum inclination of the cam plate. The rotary shaft never stops rotating. The advantages of the above sealing structure are effectively obtained, especially when applied to a compressor that withstands such harsh conditions.
The compressor includes a fluid circulation passage defined in the inside of the compressor extending through a discharge pressure zone, the crank chamber, a suction pressure zone, and the cylinder bore when the refrigerant circulation impeding means impedes refrigerant circulation in the external refrigerant circuit. A passage constituting the circulation passage connects the crank chamber with the suction pressure zone and has an opening located in the crank chamber at the vicinity of the first lip ring. Accordingly, the amount of fluid flowing in the vicinity of the first lip ring in the crank chamber becomes large during minimum inclination operation, which produces harsh conditions for the lip portion of the first lip ring. As a result, the amount of fluid necessary for lubricating the lip portions of the first lip ring and the second lip ring leaks continuously. This positively lubricates the lip portion.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view showing a clutchless type variable displacement compressor to which a first embodiment of a sealing apparatus according to the present invention is applied;
FIG. 2 is an enlarged partial cross-sectional view showing the vicinity of the sealing apparatus of FIG. 1;
FIG. 3 is a plan view of a front, or outer, side of a second lip ring before the insertion of a rotary shaft;
FIG. 4A is an enlarged cross-sectional diagram showing the flare of FIG. 2;
FIG. 4B is an enlarged cross-sectional diagram showing the flare of a sealing apparatus of a comparative example;
FIG. 4C is an enlarged cross-sectional diagram showing the flare of a sealing apparatus of another comparative example;
FIG. 5 is a graph comparing the effects of the sealing apparatus of the preferred embodiment with that of the sealing apparatus of Japanese Unexamined Patent Publication No. 6-300142, where the vertical axis indicates the temperature of the lip portion of the first lip ring, while the horizontal axis indicates the rotating speed of the rotary shaft;
FIG. 6 is an enlarged partial cross-sectional view showing a second embodiment of a sealing apparatus according to the present invention; and
FIG. 7 is an enlarged partial cross-sectional view showing the sealing apparatus of Japanese Unexamined Patent Publication No. 6-300142.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
A first embodiment according to the present invention will now be described with reference to FIG. 1 to FIG. 5.
As shown in FIG. 1, a front housing 11 is coupled to the front end of a cylinder block 12. A rear housing 13 is fixed to the rear end of the cylinder block 12 with a valve body 14 arranged in between. A crank chamber 15 is defined in the front housing 11 and the cylinder block 12. A rotary shaft 16 is rotatably supported by the front housing 11 and the cylinder block 12 extending through the crank chamber 15. One end of the rotary shaft 16 extends through the front wall of the front housing 11 and projects outward.
A boss 45 projects from the front wall of the front housing 11 and surrounds the projecting end of the rotary shaft 16. A pulley 17 is rotatably supported by an angular bearing 18 on the peripheral surface of the boss 45. The pulley 17 is connected to the end of the rotary shaft 16 projecting from the front housing 11. A belt 19 engaged with the peripheral portion of the pulley 17 directly connects the pulley 17 with a vehicle engine 20, serving as an external drive force, without using an electromagnetic clutch or the like, which is expensive and heavy and which produces shock when actuated or de-actuated. Accordingly, the rotary shaft 16 is always rotated when the engine 20 is running.
A sealing apparatus 21 that seals the rotary shaft 16 is arranged between an outer surface 161 of the rotary shaft 16 at the projecting end and the inner surface 451 of the boss portion 45. The structure of the sealing apparatus 21 will be described in detail later.
A rotary support 22 is fixed to the rotary shaft 16 in the crank chamber 15. A swash plate 23, serving as a cam plate, is supported in a manner that it is slidable and inclinable with respect to the direction of the axis L of the rotary shaft 16. A hinge mechanism 24 is arranged between the rotary support 22 and the swash plate 23. The hinge mechanism 24 enables the swash plate 23 to incline with respect to the axis L of the rotary shaft 16 while rotating integrally with the rotary shaft 16. When the center portion of the swash plate 23 moves toward the cylinder block 12, the inclination of the swash plate 23 decreases. An inclination decreasing spring 26 is arranged between the rotary support 22 and the swash plate 23. The inclination decreasing spring 26 urges the swash plate 23 in a direction that decreases the inclination. An inclination restricting projection 221 is defined in the rear surface of the rotary support 22 to restrict the maximum inclination of the swash plate 23 when abutting the swash plate 23.
An accommodating bore 121 extends through the center of the cylinder block 12. A cylindrical shutter 28, which constitutes a refrigerant circulation impeding means, is slidably accommodated in the accommodating bore 121. A suction passage opening spring 29 is arranged between the end surface of the accommodating bore 121 and the shutter 28 to urge the shutter 28 toward the swash plate 23.
The rear end of the rotary shaft 16 is inserted into the shutter 28. A radial bearing 30 is arranged between the rear end of the rotary shaft 16 and the inner surface of the shutter 28. The radial bearing 30 slides together with the shutter 28 in the direction of the axis L with respect to the rotary shaft 16.
A suction passage 131 extends through the center of the rear housing 13 and the valve body 14. The suction passage 131 is connected with the accommodating bore 121. A positioning surface 141 is defined about the outlet of the suction passage 131 on the front surface of the valve body 14. A shutting surface 281 is defined on the distal surface of the shutter 28. The shutting surface 281 contacts or moves away from the positioning surface 141 in accordance with the movement of the shutter 28. The abutment between the shutting surface 281 and the positioning surface 141 seals the space in between and disconnects the suction passage 131 from the interior space of the accommodating bore 121.
A thrust bearing 35 is arranged between the swash plate 23 and the shutter 28 and slidably supported on the rotary shaft 16. The thrust bearing 35 is urged by the suction passage opening spring 29 so that it is always held between the swash plate 23 and the shutter 28.
During inclination of the swash plate 23 toward the shutter 28, the inclination of the swash plate 23 is transmitted to the shutter 28 by the thrust bearing 35. Thus, the shutter 28 moves toward the positioning surface 141 against the urging force of the suction passage opening spring 29. This abuts the shutting surface 281 of the shutter 28 against the positioning surface 141. With the shutting surface 281 against the positioning surface 141, further inclination of the swash plate 23 is restricted. In the restricted state, the swash plate 23 is arranged at the minimum inclination, which is slightly greater than zero degrees (as measured from a plane normal to the axis L).
Cylinder bores 122 extend through the cylinder block 12. A single-headed piston 36 is accommodated in each cylinder bore 122. Each piston 36 is coupled to the peripheral portion of the swash plate 23 by shoes 37 to convert the rotational movement of the swash plate 23 to forward and reverse reciprocation of the piston 36.
A suction chamber 38, which is in a suction pressure zone, and a discharge chamber 39, which is in a discharge pressure zone, are each defined in the rear housing 13. Suction ports 142, suction flaps 143 for opening and closing the suction ports 142, discharge ports 144, and discharge flaps 145 for opening and closing the discharge ports 144 are each defined in the valve body 14. The reciprocation of each piston 36 draws refrigerant gas from the suction chamber 38 into the associated cylinder bore 122 through the associated suction ports 142 and suction flaps 143. The refrigerant gas in the cylinder bore 122 is compressed to a predetermined pressure by the reciprocating movement of the associated piston 36 and discharged into the discharge chamber 39 through the associated discharge port 144 and discharge flap 145.
The suction chamber 38 is connected to the accommodating bore 121 through an aperture 146. The abutment of the shutting surface 281 of the shutter 28 against the positioning surface 141 disconnects the aperture 146 from the suction passage 131. A conduit 46 extends along the axis of the rotary shaft 16. An inlet 461 of the conduit 46 opens in the crank chamber 15 in the vicinity of the sealing apparatus 21. An outlet 462 opens inside the shutter 28, which is in the suction pressure zone. A pressure releasing hole 282 extends through the wall of the shutter 28 and communicates the interior of the shutter 28 with the interior of the accommodating bore 121.
A pressurizing passage 48 connects the discharge chamber 39 with the crank chamber 15. A displacement control valve 49 is arranged in the pressurizing passage 48.
In the compressor of the above structure, the suction passage 131, through which refrigerant gas is drawn, and a discharge port 75, from which the refrigerant gas in the discharge chamber 39 is discharged, are connected by an external refrigerant circuit 76. A condenser 77, an expansion valve 78, and an evaporator 79 are provided in the external refrigerant circuit 76.
A temperature sensor 80 is arranged in the vicinity of the evaporator 79. The temperature sensor 80 detects the temperature of the evaporator 80 and sends detected temperature information to a control computer 81. The control valve 49 has a solenoid 491 that is actuated and de-actuated by the computer 81 based on the detected temperature information from the temperature sensor 80. When an air conditioner switch 82 is turned on, the computer 81 instructs the de-actuation of the solenoid 491 of the control valve 49 when the detected temperature becomes lower than a predetermined temperature. A temperature lower than the predetermined temperature indicates a state in which frost may form in the evaporator 79. When the air conditioner switch 82 is turned off, the computer 81 de-actuates the solenoid 491.
De-actuation of the solenoid 491 opens the pressurizing passage 48 and connects the discharge chamber 39 with the crank chamber 15. This communicates the high pressure refrigerant gas in the discharge chamber 39 with the crank chamber 15 through the pressurizing passage 48 and increases the pressure in the crank chamber 15. The pressure increase in the crank chamber 15 shifts the swash plate 23 toward the minimum inclination position.
When the shutting surface 281 of the shutter 28 abuts against the positioning surface 141, the cross-sectional passage area of the suction passage 131 becomes zero and the flow of refrigerant gas from the external refrigerant circuit 76 to the suction chamber 38 is impeded.
Since the minimum inclination of the swash plate 23 is not zero degrees, discharge from the cylinder bores 122 to the discharge chamber 39 takes place even when the swash plate inclination is minimum. The refrigerant gas in the suction chamber 38 is drawn into the cylinder bores 122 and discharged into the discharge chamber 39. In other words, when the swash plate inclination is minimum, a circulation passage is formed in the compressor extending through the discharge chamber 39, the pressurizing passage 48, the crank chamber 15, the conduit 46, the pressure releasing hole 282, the suction chamber 38, and the cylinder bores 122. Fluid moving together with the refrigerant gas (mainly lubricating oil) passes through the circulation passage to lubricate the interior of the compressor. There is a difference in pressure between the discharge chamber 39, the crank chamber 15, and the suction chamber 38. The pressure difference and the cross-sectional passage area of the pressure releasing hole 282 holds the swash plate 23 at the minimum inclination in a stable manner.
The actuation of the solenoid 491 closes the pressurizing passage 48 and the pressure in the crank chamber 15 is released through the conduit 46 and the pressure releasing hole 282. This decreases the pressure of the crank chamber 15. The pressure decrease shifts the swash plate 23 from the minimum inclination to the maximum inclination.
The sealing apparatus 21 will now be described.
As shown in FIG. 2, a case 51 includes a large cylindrical portion 511 and a small cylindrical portion 512. The case 51 is inserted into the boss 45. Movement of the case 51 toward the crank chamber 15 is restricted by the abutment of the distal end of the small cylindrical portion 512 against a stepped wall surface 452 defined in the rearward end of the boss 45. The movement of the case 51 toward the outside of the compressor is restricted by the abutment of the large cylindrical portion 511 against a snap ring 52 fitted into the inner surface 451 of the boss 45. An O-ring 53 is fitted onto the small cylindrical portion 512 and is in contact with the inner surface 451 of the boss 45.
A first lip ring 54, which is made of a synthetic resin such as acrylonitrile-butadiene rubber, is held by a first holding piece 55. A second lip ring 56, which is made of a fluororesin such as PTFE (polytetrafluoroethylene), is arranged at the front, or outer, side of the first lip ring 54. A posture maintaining ring 61, or posture maintaining member, is arranged between the first lip ring 54 and the second lip ring 56. A second holding piece 58 is arranged at the front, or outer, side of the second lip ring 56. These members 54-56, 58, 61 are accommodated in the case 51. In the case 51, the first holding piece 55 abuts against a stepped surface 513 connecting the large cylindrical portion 511 with the small cylindrical portion 512. The second holding piece 58 abuts against an end 514, which is bent radially inward, of the large cylindrical portion 511. Thus, the first lip ring 54, the second lip ring 56, and the posture maintaining ring 61 are held between the first holding piece 55 and a second holding piece 58.
The first lip ring 54 has a peripheral sealing portion 541, which is in contact with the inner surface of the large cylindrical portion 511, and a lip portion 542, which is in contact with the outer surface 161 of the rotary shaft 16. The lip portion 542 extends through the interior of the case 51 toward the crank chamber 15. The distal end of the lip portion 542 is inclined radially downward. An acute flare 59 has an inclined surface 591 at the distal part of the lip as shown in FIG. 2 and FIG. 4A. The inner annular edge 593 of the flare 59 is in contact with the outer surface 161 of the rotary shaft 16 along an annular region.
FIG. 4A is an enlarged view of the vicinity of the flare 59 of FIG. 2. As shown in the drawing, the surface 591 defining the crank chamber side of the flare 59 is inclined with respect to the outer surface 161 of the rotary shaft 16 by a predetermined angle θ1. In the same manner, an inclined surface 592 defining the compressor exterior side of the flare 59 is inclined with respect to the outer surface 161 of the rotary shaft 16 by a predetermined angle θ2. The contacting posture of the lip portion 542 is arranged so that the angle θ1 between the inclined surface 591 and the outer surface 161 and the angle θ2 between the inclined surface 592 and the outer surface 161 satisfies the relationship of θ1<θ2. The lip portion 542 of the first lip ring 54 seals effectively when rotation of the rotary shaft 16 is stopped but permits leakage of fluid from the crank chamber 15 toward the second lip ring 56 during rotation of the rotary shaft 16.
FIG. 4B shows a comparative example in which the contacting posture of the lip portion 542 with respect to the rotary shaft 16 satisfies the relationship of θ1=θ2. FIG. 4C shows a comparative example in which the contacting posture of the lip portion 542 with respect to the rotary shaft 16 satisfies the relationship of θ1>θ2. These comparative examples differ from the preferred embodiment in that fluid leakage from the crank chamber toward the second lip ring 56 is not permitted during rotation of the rotary shaft 16.
The difference between the preferred embodiment and the comparative examples will now be described. As shown in FIGS. 4A, 4B, and 4C, the flare 59 elastically contacts the outer surface 161 of the rotary shaft 16, with the vicinity of its inner annular edge 593 flattened. The portion of the flare 59 contacting the outer surface 161 of the rotary shaft 16 includes the inner annular edge 593 and has a certain sealing width (as measured in the axial direction of the shaft 16). The double-dotted curved lines of FIGS. 4A, 4B, 4C show the force distribution of the contact pressure of the flare 59 applied to the outer surface 161. As apparent from the distribution, if the contacting posture of the lip portion 542 with respect to the rotary shaft 16 satisfies the condition of θ1=θ2, the flare 59 is flattened so that the peak of the contact pressure, or the inner annular edge 593, is located at the center of the sealing width (indicated by the vertical broken line FIG. 4B) If the condition of θ1>θ2 is satisfied, the flare 59 is flattened with the inner annular edge 593 located at a position offset from the center (indicated by the vertical broken line in FIG. 4C) toward the crank chamber 15. If the condition of θ1<θ2 is satisfied, the flare 59 is flattened with its inner annular edge 593 located at a position offset from the center toward the pulley 17. In other words, it can be presumed that the sealing capability of the affected greatly by how the flare 59 is flattened.
FIG. 3 shows the second lip ring 56 before insertion of the rotary shaft 16. In this state, the second lip ring 56 is flat. As shown in FIG. 2, when the rotary shaft 16 is inserted, the inner portion of the second lip ring 56 is bent toward the crank chamber 15. The bent portion defines a lip portion 60. The lip portion 60 includes a seal surface 601 having a predetermined width (as measured in the axial direction of the shaft 16). The seal surface 601 contacts the outer surface 161 of the rotary shaft 16 along an annular region. Most of the lip portion 60 is included in the space between the lip portion 542 of the first lip ring 54 and the outer surface 161 of the rotary shaft 16. The overlapping of the lip portion 542 of the first lip ring 54 and the lip portion 60 of the second lip ring 56 reduces the size of the sealing apparatus 21 in the direction of the axis L.
A pump groove 602 extends spirally about the axis (L) of the second lip ring 56 in the seal surface 601 of the lip portion 60. Accordingly, a spiral pump structure actuated by the rotation of the rotary shaft 16 is defined by the pump groove 602 and the opposing outer surface 161 of the rotary shaft 16. The pump groove 602 is provided only at the crank chamber end of the seal surface 601 and not the compressor exterior end of the seal surface 601. That is, the groove 602 is not formed in the front end (the end nearest to the pulley 17) of the seal surface 601
The posture maintaining ring 61 has a peripheral portion 611 held between the first lip ring 54 and the second lip ring 56. The posture maintaining ring 61 also has an inner portion 612 that is bent to extend toward the crank chamber 15 to separate the lip portion 542 of the first lip ring 54 from the lip portion 60 of the second lip ring 56. A posture maintaining portion 613, which is curved radially inward, is defined at the distal or rearward portion of the inner portion 612. The posture maintaining portion 613 contacts the lip portion 542 of the first lip ring 54 to support the lip portion 542 from the side of the compressor exterior. The curved posture maintaining portion 613 enables low-pressure contact with the lip portion 542. As apparent from the drawing, a space is provided between the inner portion 612 of the posture maintaining ring 61 and the lip portion 60 of the second lip ring 56.
The operation of the sealing apparatus 21 will now be described.
When the engine 20 is stopped and the rotation of the rotary shaft 16 is stopped, the elasticity of the lip portion 542 of the first lip ring 54 causes the lip portion 542 to contact the outer surface 161 of the rotary shaft 16. Accordingly, the leakage of fluid (refrigerant or lubricating oil) from the crank chamber 15, which is inside the compressor, toward the exterior of the compressor is prevented.
However, as described above, the lip portion 542 of the first lip ring 54 is arranged so that it enables leakage of fluid toward the second lip ring 56 during rotation of the rotary shaft 16. Accordingly, when the engine 20 is started and the rotary shaft 16 is rotated, some fluid in the crank chamber 15 leaks from the lip portion 542 toward the second lip ring 56. However, the lip portion 60 of the second lip ring 56 seals in the fluid that leaks from the lip portion 542 and prevents the fluid from leaking out of the compressor. Relative rotation between the groove 602 and the outer surface 161 produces a pumping effect and positively returns the fluid to the crank chamber 15 through the pump groove 602. This enhances the sealing capability of the lip portion 60.
During rotation of the rotary shaft 16, the leakage of fluid from the lip portion 542 of the first lip ring 54 enables fluid (mainly lubricating oil) to lubricate the lip portion 542 of the first lip ring 54 and the lip portion 60 of the second lip ring 56. This prevents frictional deterioration and thermal deterioration of the lip portions 542, 60.
The following advantages are obtained from the structure of the preferred embodiment.
(1) During minimum inclination operation of the compressor, the high pressure refrigerant gas in the discharge chamber 39 may increase the pressure of the crank chamber 15 to, for example, about 7 kgf/cm 2 (gauge). The high pressure of the crank chamber 15 tends to deform the first lip ring 54. However, the lip portion 542 of the first lip ring 54 is supported by the posture maintaining portion 613 of the posture maintaining ring 61. This prevents deformation of the first lip ring 54. Therefore, the first lip ring 54 does not press the lip portion 60 of the second lip ring 56 against the outer surface 161 of the rotary shaft 16 with excessive force. As a result, excessive heating of the lip portion is avoided. This prevents heating of the lip portion 60, which is made of a synthetic rubber, which has a heat resistance that is inferior to fluororesin, and improves the durability of the sealing apparatus 21.
(2) The contacting posture of the lip portion 542 with respect to the rotary shaft 16 is arranged so that the angle θ1 between the inclined surface 591 and the outer surface 161 and the angle θ2 between the inclined surface 592 and the peripheral surface 161 satisfies the relationship of θ1<θ2. Accordingly, the lip portion 542 seals effectively when the rotation of the rotary shaft 16 is stopped while preventing a large amount of fluid leakage during rotation of the rotary shaft 16. This results in satisfactory lubrication of the lip portion 542 of the first lip ring 54. Thus, as marked by the squares in FIG. 5, the heating of the lip portion 542 is reduced in comparison with the sealing apparatus of Japanese Unexamined Patent Publication No. 6-300142 (marked by circles) under the same conditions.
(3) The pump groove 602 is defined in the lip portion 60 of the second lip ring 56. A spiral pumping effect is produced by the pump groove 602 and the outer surface 161 during rotation of the rotary shaft 16. Accordingly, the sealing performance of the lip portion 60 of the second lip ring 56 is improved. The improvement of the sealing performance of the lip portion 60 during rotation of the rotary shaft 16 prevents degradation of the sealing performance of the entire sealing apparatus 21, even if leakage of fluid from the lip portion 542 of the first lip ring 54 is permitted.
(4) The pump groove 602 is provided only at the crank chamber side of the seal surface 601 of the lip portion 60 and not the compressor exterior side of the seal surface 601. In other words, the pump groove 602 does not open toward the exterior of the compressor. Accordingly, in cases such as when the rotation of the rotary shaft 16 is stopped, the residual fluid in the pump groove 602 does not flow out of the compressor. This improves the sealing performance of the sealing apparatus 21 when the rotation of the rotary shaft 16 is stopped.
(5) The compressor of the preferred embodiment is a variable displacement compressor. Thus, displacement is varied by adjusting the pressure of the crank chamber 15. Accordingly, the pressure in the crank chamber 15 becomes high during minimum inclination operation. The advantages of the above sealing structure 21 are especially effective when applied to a variable displacement compressor that withstands such harsh conditions.
(6) Further to the above advantage (5), the compressor of the preferred embodiment is a clutchless compressor and the rotary shaft 16 is always rotated when the engine 20 is running. That is, the lip portion 542 of the first lip ring 54 always slides along the outer surface 161 of the rotary shaft 16 when the engine 20 is running. As described above, the pressure of the crank chamber 15 is high during minimum displacement operation. In addition, minimum displacement operation may be continued for a long period of time during the winter. The advantages of the above sealing structure 21 are especially effective when applied to a variable displacement compressor that withstands such harsh conditions.
(7) The inlet 461 of the conduit 46, which constitutes an internal circulation passage for fluid during minimum displacement operation, is located in the vicinity of the first lip ring 54 of the sealing apparatus 21. Accordingly, during minimum inclination operation, which produces a harsh environment for the sealing apparatus 21, there is an increase in the amount of fluid flowing in the vicinity of the first lip ring 54 in the crank chamber 15. As a result, the required amount of fluid necessary for lubricating the lip portion 542 leaks continuously. This further reduces heating of the lip portion 60.
Second Embodiment
FIG. 6 shows a second embodiment. In addition to the main sealing structure of the sealing apparatus 21 of the first embodiment, a sealing apparatus 71 of this embodiment includes a fluororesin third lip ring 72, the structure of which is similar to the second lip ring 56. The third lip ring 72 is arranged at the outer side of the second lip ring 56 and has a lip portion 721 that contacts the outer surface 161 of the rotary shaft 16. The lip portion 721 is not provided with the pump groove 602.
The following advantages are obtained from the structure of this embodiment.
(1) The sealing apparatus 71 has the third lip ring 72. Accordingly, if the second lip ring 56 deteriorates, the lip portion 721 of the third lip ring 72 functions as a further seal and prevents the fluid in the crank chamber 15 from leaking out of the compressor. This further improves the durability of the sealing apparatus 71.
(2) The lip portion 721 of the third lip ring 72 prevents dust or the like from entering the compressor. Accordingly, the lip portion 60 of the second lip ring 56 is not exposed to dust. This improves the sealing performance of the second lip ring 56 and enhances the sealing performance of the sealing apparatus 71.
The present invention may be embodied as described below without departing from the spirit or scope of the invention.
(1) In the above embodiments, the contacting posture of the lip portion 542 with respect to the rotary shaft 16 may be arranged as shown in FIG. 4B or FIG. 4C. Even if arranged in such manner, the supporting function of the posture maintaining ring 61 prevents the first lip ring 54 from pressing the lip portion 60 of the second lip ring 56 against the rotary shaft 16 while permitting a small amount of fluid to flow toward the second lip ring 56 during rotation of the rotary shaft 16. Thus, as marked by the triangles in FIG. 5, the heating of the lip portion 542 of the lip ring 56 is positively reduced in comparison with the sealing apparatus of Japanese Unexamined Patent Publication No. 6-300142 (marked by circles).
(2) In the above embodiments, the contacting posture of the lip portion 542 with respect to the rotary shaft 16 may be arranged so that fluid does not leak even when the rotary shaft 16 is rotating.
(3) The present embodiment may be applied to the sealing structure of a compressor employing a clutch. | A sealing structure for the shaft of a compressor. The sealing apparatus includes an inner ring, and outer ring, and a support ring. The inner ring and the outer rings have flexible annular lips that contact the surface of the rotary shaft. The support ring supports the inner lip and determines the position of the inner lip. The first lip permits fluid leakage along the surface of the shaft, while the second lip forms a fluid-tight seal with the shaft. The support ring prevents the internal pressure of the compressor from pressing the first lip against the shaft with excessive force, which extends the life of the sealing apparatus. | 5 |
BACKGROUND OF THE INVENTION
[0001] People in small boats end up in the water for a variety of reasons. Rowers in inherently unstable crew shells often work out in unfavorable conditions of cold weather and rough water made worse by wind and should get out of the water as quickly as possible when the boat swamps or turns over. Any boat presents difficulties when a swimmer tries to lift him or herself over the gunnels (gunwales) and back into the boat or into a rescue boat.
[0002] A number of so-called folding ladders have been designed to aid in this difficulty but a majority of them are non-rigid rope ladders that are tossed over the side and all have the inherent problem of becoming unstable and difficult to climb because they tend to be forced under the bottom of the boat as the swimmer puts weight on the bottom rung. Such a folding ladder can be seen at:
[0000] (http://www.mysticmarinediscounts.com/sea-dog-corp-folding-ladder-5825011-ladder-five-step-rope.html)
[0003] A similar ladder is shown in FIG. 8 with rungs 100 , rails 200 , and rope 300 threaded through the rungs and rails. When held by the rope ends 400 designed to attach the ladder to a boat, gravity will drop the rails and rungs to straighten the rope, forming a ladder with parallel rails 500 and parallel rungs perpendicular to the rails. Rope ladders have no “stand-off” feature and most of the straight rigid ladders that hook over the side rail of the hull do not have any such feature. Without this “stand-off,” the swimmers fingers and toes on the rungs of most such ladders are therefore jammed up against the hull, making it difficult or less secure to get a safe grip while attempting to climb into the boat.
[0004] Similarly, there are many folding ladders on the market that have mechanical hinges that have to be opened as the ladder is deployed. See U.S. Pat. No. 6,145,621 to Nye. Not only are these mechanical parts potentially subject to jamming (making them difficult and time-consuming to open), but alternatively they may become loosened and unstable once they are opened and such movement could eventually compromise the safety and reliability of the ladder.
[0005] Likewise, almost all of the boat ladders on the market have to have some external means of attaching them to the boat—such as a bracket screwed permanently into the hull at a particular location into which the ladder is fitted during use, or to which the ladder itself is permanently attached in its folded position when not deployed for rescuing an overboard swimmer. This prohibits the ladder from being deployed at the position on the boat where it is needed. If the water is cold, the swimmer should get into the boat quickly to avoid hypothermia. Indeed, even the simple rope ladders have to be tied onto a rail or some other structure on the boat, which only adds additional time and uncertainty during an emergency rescue.
[0006] As for those rigid ladders which do have some sort of stand-off feature, the stand-off feature usually consists of some short legs extending horizontally from the side rails to hold the ladder away from the side of the hull. See U.S. Pat. No. 5,113,782 (McCarty), U.S. Pat. No. 2,924,291 (Tunstead), Des. 185,212 and U.S. Pat. No. 2,992,697 (Klages), and U.S. Pat. No. 3,512,608 (Huntley). These short legs sometimes fold out from the rails. This mechanical feature adds to the complexity of the device, potentially increases the time for deployment, and may in fact prove to be totally useless if it is at the bottom of the ladder and below the bottom of the hull on a shallow-draft boat like a jonboat (usually termed a “launch”) used by a crew coach to follow the shell during practice sessions, etc. These launches or chase boats are required to carry a safety equipment bag including life vests. If a quickly deployable ladder were available to fit in the safety equipment bag carried by chase boats, the rowers' safety would be enhanced in a simple and effective way.
SUMMARY OF THE INVENTION
[0007] There is a need for a small, rigid-when-deployed, quickly deployable ladder capable of easy attachment to the gunnels of a watercraft in an emergency situation to allow a swimmer to lift him or herself out of the water into the craft as quickly as possible. Instant deployment is important for obvious safety reasons. U.S. Pat. No. 5,329,873 to Tiballi recognizes the need for quick deployment of a safety dive flag from a folded position. The flag is folded in a small, convenient bundle in FIG. 5 of Tiballi and is quickly erected using tube sections joined by elastic cord 30 of FIG. 4 in Tiballi.
[0008] The ladder of the invention has rigid side rails and will maintain its vertical (or even slightly inclined away from the boat) position against the boat hull as the swimmer climbs up the rungs, which provides a far more secure and safe operation than the instability of a swinging rope ladder.
[0009] The ladder of the invention has no mechanical hinges connecting the rungs to the rails. Rather, the rungs automatically insert into the rails when opened to form a secure and fool-proof connection that is not subject to movement during use. Bungee cord (shock cord) is threaded through the rails and rungs and held under tension when the ladder is folded. The assembly remains under tension when the folded ladder is released to allow the rungs to be positioned between the rails and nest in the rails to form a rigid ladder.
[0010] The ladder of the invention snaps open instantly from its folded storage state and can immediately be hung over the gunnels of a water craft when needed, and can be positioned at any position on the boat gunnels to be deployed closest to the swimmer in need of help. The hooks at the top of the rails of the inventive ladder are intended to be compatible with the gunnels of a standard jonboat, but will also work on a canoe. These hooks can easily be modified to present a more universal geometry to fit any boat rail or gunnel. A second set of different shaped hooks on the bottom end of the ladder rails can be provided so that the device could be deployed on boats with various shaped gunnels or transoms simply by turning it upside down and hanging it using whichever set of hooks best fit a particular gunnel.
[0011] The inventive ladder has a built in “stand-off”, projection, or protrusion to engage the hull on each rail that keeps it hanging at least vertically or slightly inclined away from the hull during deployment, making it far easier for a swimmer to climb up the rungs. The ladder of this invention is designed with a bulge at the top of the device just below the hooks that serves to hold the rails away from the side of the boat so that the swimmer's fingers and toes have room to securely grab onto the rungs without hitting the hull. Moreover, since this stand-off bulge is at the top of the ladder, it will properly function even on very shallow-draft hulls, unlike the stand-off legs that are at the bottom of many rigid ladders. Finally, that the design of the bulge is intended to press the rails against the hull when the swimmer's weight is on the ladder, which makes sure the hooks stay fully engaged on the gunnel and the ladder remains firmly in place as the swimmer ascends into the boat.
[0012] The inventive ladder is constructed to float if it is accidentally dropped overboard, which most likely is not true with the prior art rigid mechanical ladders, most of which are made of aluminum or stainless steel. The present design using plywood rails floats naturally.
[0013] These and other features and advantages will be evident from the drawings and detailed description below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a plan view of the inventive ladder in the erected state;
[0015] FIG. 2 is a side view of the erected ladder;
[0016] FIG. 3 is a vertical section through a rail hole showing the relationship of the hole, the rung and the elastic cord;
[0017] FIG. 4 is a plan view of the ladder in the folded state;
[0018] FIG. 5 is a side view of the ladder in the folded state;
[0019] FIG. 6 shows the ladder mounted on the side of a jonboat;
[0020] FIG. 7 shows the ladder mounted to the side of a canoe; the ladder having mounting means on each end, one end mounted to a canoe rail;
[0021] FIG. 8 shows a conventional collapsing ladder.
DETAILED DESCRIPTION
[0022] FIGS. 1 and 2 show the folding ladder of the invention. Single piece rails 1 comprise a top end 50 , a bottom end 60 , a series of holes 2 into which rungs 3 fit snuggly to form the ladder. The rungs 3 and holes 2 are tapered to mate snuggly to form a rigid connection when tensioned together by bungee cord 4 . The bungee cord is held in tension by appropriate knots 5 . Any means can be employed to prevent the knot 5 from passing through hole 4 . The tension of the bungee is sufficient to bring the rungs and rails into alignment to mate the rungs 3 with the holes 2 , forming a rigid ladder when the ladder is released from its folded orientation, described below.
[0023] FIG. 3 shows the rungs 3 and hole 2 . The rung 3 in the figure has tapered ends 6 (only one end shown) pulled into tapered hole 7 of rail 1 by the tension of bungee cord 2 (in the direction of the arrow in FIG. 3 ) but the holes and rungs preferably have straight walls. A straight walled rung end 3 will properly seat in a straight walled hole. The rung entry end of hole 2 will have a larger diameter than the bungee cord exit end of the hole. When the hole is straight walled, a shoulder between the larger and small diameters will stop the rung at an intermediate position in the hole to seat it securely, held by the tension of bungee cord 4 .
[0024] The ladder is assembled by threading a bungee cord 4 through one of the top or bottom-most rail holes 2 with a knot 5 on the end of the cord. Cord 4 is then passed through a rung 3 and through the opposite rail, passed up to the next hole on the same rail, through a rung and so on until the cord 4 exits the last unfilled hole 2 , following the dotted line with arrows of FIG. 1 ). The cord 4 is tensioned and a second knot is tied to keep the cord from passing through the last hole. The tension is sufficient to hold the ladder in its “use” configuration but loose enough to allow folding of the ladder as described below. Sufficient cord if left beyond the knot 5 at the top of the ladder to hold the ladder in the folded orientation of FIG. 4 . An additional knot or other enlargement 9 is placed on the end of cord 4 to maintain the cord in slot 8 when the ladder is folded.
[0025] FIGS. 4 and 5 show the ladder of the invention in its folded orientation. The ladder is folded by forcing the rails 1 slightly apart to allow the tapered rungs ends 6 to move out of tapered holes 7 and forcing one of the rails 1 downwardly with respect to the other rail. This allows the rails 1 to trap the rungs 3 in a position parallel to the rails 1 as the rails are moved closer to each other with the rungs lying therebetween as shown in FIGS. 4 and 5 . Once positioned as in figured 4 and 5 , the bungee cord end 9 is manually drawn into slot 8 thereby holding the rails closed on the rungs maintaining the ladder in the folded position of FIGS. 4 and 5 . In the folded orientation, the ladder can be stowed anywhere on the craft, preferably in the required safety equipment bag (in the case where the ladder is employed by a crew launch). The cord end 9 can be of any construction capable of keeping the cord from passing through the slot 8 when the ladder is folded. A simple knot or the combination of a knot and apertured element could be used. A cane tip with a hole therethrough with a knotted bungee has proved effective.
[0026] Folding the ladder can be a bit awkward but it is important to note that folding is accomplished at a non-critical time. Assuming the ladder is used to rescue a swimmer, the ladder has been instantly erected for use when pulled from its stowed position (described below), hooked to the gunnel of the launch boat, used by the swimmer to get in the launch, and removed from the gunnel as the swimmer is taken to safely either on shore or on a bigger boat. The ladder can be re-folded any time prior to re-use of the launch or the safety equipment bag, in the case of crew use.
[0027] The folded ladder of FIGS. 4 and 5 can be instantly erected for use simply by removing bungee cord end 9 from slot 8 . When released, the tension of the bungee cord 4 draws the tapered rungs ends 6 into the tapered holes 7 of the rails forcing the ladder into the position of FIGS. 1 and 2 . Since the force of a swimmer on the rungs is vertical with the ladder in a vertical orientation on the boat, the ladder maintains its FIGS. 1 and 2 orientation to allow the swimmer to climb into the boat to which it is attached.
[0028] A critical element of the invention is the means by which the ladder attached to the boat gunnels. FIG. 6 shows boat 20 (a jonboat boat, in this figure) having gunnels 21 . The inventive ladder has hooks at the ends of rails 1 . Hooks 22 have openings 23 sized to fit over gunnels 21 . The hooks can be sized for any boat gunnel and are optimally sized to fit many common gunnels. The ladder ends also include a protrusion or bulge 24 to provide the stand-off feature of the ladder. Protrusion 24 lies against the boat hull sidewall 25 at point X to act with the hooks 22 to keep the ladder from moving with respect boat sidewall when under the load of a swimmer exiting the water. Since the protrusion 24 is at the top of the ladder, it will properly function on very shallow-draft hulls, unlike the previously mentioned stand-off legs at the bottom of many rigid ladders. The relationship between hooks 22 , opening 23 , and protrusion 24 orients the ladder at least vertically and optimally at an angle away from the boat (a canoe) as shown in FIG. 7 . The important point here is that the swimmers can't force the ladder under the boat, preventing injury to feet and hands that would be trapped between the ladder and the boat sidewall and allowing easier exit from the water because of the positive angle of the ladder with respect to the boat. Of course, some boat hulls/gunnels are dimensioned such that the protrusions 24 are unnecessary for maintaining the ladder in the optimal position of at least vertical and, preferably, angled away from the boat hull as described elsewhere in this specification.
[0029] Hooks 22 can be provided on either end of the ladder as shown in FIG. 7 and be of different configuration on each end to allow a single ladder to be attached to various boat gunnels/sidewalls. The protrusion can be of any size or shape to mate with any sidewall. Hooks 26 on end 60 of the rails 1 can face in either direction (shown in FIG. 7 oriented in the same direction as hooks 22 ) to be attached to boat structure when the ladder is rotated 180 degrees such that hooks 26 are at the top of the ladder. Hooks 26 and/or protrusion/projection 25 are of different dimension than hooks 22 and/or projections 24 . FIG. 7 clearly show the inventive ladder positioned at a positive angle from vertical making climbing much easier than if the ladder were allowed to move past vertical and under the boat hull.
[0030] Some boats will not accept the hooks described herein. It is anticipated that other attaching means can be used with the hooks. Knotted rope can mate with a variety of boat structures. The important aspect of this invention is that the ladder stand off from the boat sidewall to be near vertical and preferable angled away from the boat for easy use. Also, the ladder hooks can mount to any boat structure that will accept it such as existing fixed ladders, rear transoms, motor mounts or hand rails above gunnels. The ladder could be securely hung from a cleat, or a railing, or even the bracket for the outboard motor on some sailboats. Inasmuch as the ladder can be an emergency device, the means of hanging it on the boat within reach of the stranded swimmer in the water does not have to be particularly elegant, only quick and reasonably secure. It could be used even on boats that had gunwales too wide for the hooks and the user could attach a short (e.g. 3 foot) knotted rope to one of the hooks, with the free end of this rope looped inboard around a cleat, stanchion, winch, railing, or other nearby structure on the boat and then brought back to be inserted into the slot 8 in the other hook. If this short rope were already knotted at 6 inch intervals, the height of the ladder as it hung over the side of the hull could be easily and quickly adjusted simply by choosing which knot on the rope to insert in the slot 8 in the ladder. In fact, although it would be desirable for stability purposes that the hooks actually “grabbed” over the top of the gunwale. On sailboats and other boats like the Boston Whaler™ this might not always be possible because of their “smooth gunwale” design, the ladder would still be held securely in position by the looped rope in any event—and it would be far quicker to deploy and more stable to use than the non-rigid rope ladders that are presently on the market which need to be individually tied the boat's structure in some fashion before they are deployed overboard.
[0031] It is envisioned the ladder will float if dropped into the water. The rails 1 of the preferred embodiment are constructed from plastic or plywood and the rungs 3 of PVC. Materials are not critical to the invention provided they possess the required strength and desired characteristics (floatable, for one).
[0032] The dimension shown in the drawings are not meant to be limiting in any way. The invention is limited only by the claims. | A folding, self-erecting ladder for use in the marine environment comprises two rigid side rails with holes for holding rungs. Bungee cord is thread through the rungs and rails to tension the rails toward each other top hold the rungs in the rail holes. The ladder can be folded by pulling the rails apart, allowing the rungs to leave the rail holes, and moving the rails closer to each other, trapping the rungs therebetween, and binding the folded ladder to hold it in the folded position. | 4 |
This application claims the benefit of U.S. Provisional No. 60/016,500 filed Apr. 30, 1996.
BACKGROUND OF THE INVENTION
This invention relates to a connector piece for joining two beam members. A connector piece designed according to this invention is particularly useful in making a vehicle frame including several distinct modules or subassemblies.
Passenger vehicle body frames typically include a ladder-type construction or a unibody structure. These structures have been used for many years and are well known in the art. Although conventional structures have proven useful, it is desirable to improve upon existing vehicle constructions.
For example, the automotive industry is constantly trying to reduce the weight of vehicles to improve fuel economy without reducing or sacrificing structural integrity. Further, it is desirable to provide vehicles that are more able to withstand impact collisions and provide more safety to passengers. Various attempts have been made to achieve improvements such as substituting different materials for part of or all of the vehicle frame. Although materials such as aluminum or composites have lightweight advantages, structural stability is typically sacrificed. Moreover, many substitute materials prove prohibitively expensive and, therefore, are not feasible.
Another disadvantage associated with conventional vehicle frames is that certain difficulties and complexities are presented during the assembly process. For example, vehicle frames include forwardly extending midrails that protrude through the area that serves as the engine compartment. Assembly of the drivetrain and the front suspension system for the vehicle is more difficult because of the presence of the midrails. It would be advantageous, for example, to be able to completely assemble the suspension system before mounting it on the vehicle. Conventional frames, however, make such pre-assembly impractical or impossible.
This invention is part of a vehicle body frame that represents a dramatic improvement over the art. The ease of vehicle manufacture is greatly enhanced. The structural stability and durability of the frame is increased. Passenger safety also is enhanced because of the design of a body frame according to this invention. One of the challenges in making such a vehicle body frame was to develop connector pieces to join various beam members that make up the frame. The connector piece of this invention is useful in a vehicle body frame, however, its application extends beyond vehicle body frames to virtually any application where two beam members are joined together.
SUMMARY OF THE INVENTION
In general terms, this invention is an assembly of first and second beam members and a connector piece for joining the two beam members. The two beam members each have two side walls. A first load bearing member extends generally between the first beam member side walls such that a first end of the first load bearing member is aligned with one of the first beam member side walls and a second end of the first load bearing member is aligned with the other sidewall on the first beam member. A second load bearing member extends generally between the second beam member side walls such that a first end of the second load bearing member is aligned with one of the second beam member side walls and a second end of the second load bearing member is aligned with the other sidewall on the second beam member. The first end of the second load bearing member is connected to the first end of the first load bearing member. A third load bearing member extends between the first load bearing member second end and the second load bearing member second end such that a load on one of the side walls of one of the beam members is transferred along one of the load bearing members.
The various other features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the presently preferred embodiment. The drawings that accompany the detailed description can be described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a simplified vehicle body frame that illustrates the structural principles of this invention.
FIG. 2 is a schematic illustration of the embodiment of FIG. 1 with additional energy absorbing modules.
FIG. 3 is a schematic, exploded illustration of the embodiment of FIG. 2 modified to provide front and rear wheel clearances.
FIG. 4 is a perspective, diagrammatic illustration of a vehicle body frame designed according to this invention.
FIG. 5 is an exploded view of the front end of the embodiment of FIG. 4 showing how the front end of the frame comprises several modules.
FIG. 6 is a partial cross sectional view of a connection between portions of the frame shown in FIGS. 4 and 5.
FIG. 7 is a diagrammatic illustration of a mounting joint for use with a vehicle frame designed according to this invention.
FIG. 8 is a diagrammatic illustration of a preferred mounting joint used with the body frame of FIG. 5.
FIG. 9 is a diagrammatic illustration of a preferred embodiment of an energy absorbing tube used as part of this invention.
FIG. 10 is a cross-sectional view taken along the lines 10--10 in FIG. 9.
FIG. 11 is a diagrammatic, exploded view of a rear portion of the embodiment of FIG. 5 showing how it includes several modules.
FIG. 12 is a diagrammatic illustration of a preferred connection between portions of a frame designed according to this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 schematically illustrates the structural arrangement of a vehicle body frame 20. A passenger compartment 22 includes a pair of side rails 32 that extend between a generally rectangular front portion 23 and a generally rectangular rear portion 27. The front and rear portions are rigid and resist flexing or twisting. Accordingly, the connection between the side rails 32 and the front portion 23 and the rear portion 27 provides a very rigid and stable vehicle frame 20. The generally rectangular portions 23 and 27 are the primary frame lateral reinforcement between the side rails 32 and provide torsional stiffness to the frame 20.
FIG. 2 schematically illustrates the addition of a front energy absorbing module 26 to the front portion 23. The front energy absorbing module 26 is designed to absorb impact or collision energy in a manner to be described below. Similarly, a rear energy absorbing module 30 is added to the rear portion 28. The front energy absorbing module 26 contributes to the torsional stiffness of the frame 20. The rear energy absorbing module 30 does not contribute to the torsional stiffness because the top of that module must be open for trunk access.
FIG. 3 schematically illustrates a modification to the embodiment of FIG. 2. The front portion 23 and the rear portion 27 are modified to allow for clearance for the wheels of the vehicle. The portions 23 and 27, however, are still rigid and resist twisting or flexing. FIG. 3 also schematically illustrates how the modified front and rear portions are divided into subassemblies. The front portion 23 is divided into a front suspension module 24 and a front energy absorbing module 26. The rear portion 27 is divided into a rear suspension module 28 and a rear energy absorbing module 30.
Building a vehicle frame out of the modules as diagrammatically illustrated, provides the ability to produce the vehicle frame from a plurality of subassemblies or modules. For example, the passenger compartment 22 preferably is assembled as a complete module. Similarly, the front suspension module 24 and the components of the vehicle front suspension preferably are pre-assembled as a complete module and then attached to the front of the passenger compartment module 22. The front energy absorbing module 26, which has been pre-assembled, is then attached to the front of the passenger compartment 22 and the front suspension module 24. Likewise, the rear frame portion preferably is assembled by completing the rear suspension module 28 and the suspension components before connecting them to the passenger compartment module 22. The rear energy absorbing module 30 then is attached to the rear suspension module 28 and the passenger compartment 22.
The above description and FIGS. 1 through 3 schematically illustrate the principles of design of a vehicle body designed according to this invention. The combination of distinct modules greatly facilitates and enhances the vehicle frame manufacturing process and enhances vehicle structural efficiency and passenger safety.
FIG. 4 diagrammatically illustrates a modular vehicle body frame 20 designed according to the above principles. A passenger compartment module 22 is attached to a front suspension module 24 at one end. A front energy absorbing module 26 is attached to the passenger compartment module 22 and the front suspension module 24, respectively. A rear suspension module 28 is connected to a second end of the passenger compartment module 22. A rear energy absorbing module 30 is connected to the rear suspension module 28 and the passenger compartment module 22, respectively. Details about the connections between the various modules will be provided below.
The passenger compartment module 22 includes a pair of side rails 32. The side rails 32 preferably are made up of several pieces. Rocker channels or primary rail portions 34 preferably are constructed or formed of fabricated open channel sections having a generally U-shaped cross-section. A front hinge pillar 36 is connected to one end of the rocker channel 34. A front rail extension or first end rail portion 38 is connected to the other end of the front hinge pillar 36. The other end of the rocker 34 is connected to a rear latch pillar 40 that is also connected to a rear rail extension or second end rail portion 42. The primary rail portions 34 preferably are generally parallel to the end rail portions 38 and 42. The alignment can be varied within a range from zero to twenty degrees, depending on a particular application.
The various portions of the side rail 32 preferably are interconnected with cast nodes 44. The cast nodes 44 are described in more detail below.
The passenger compartment 22 has a lower panel 46 extending between the two side rails 32. As can be seen in the drawing, the lower panel 46 includes a dash portion or fire wall 48, a floor panel 52, a seat back portion 53 and a package shelf 54. The lower panel 46 extends between the two side rails 32. The structural stability of the frame 20 is provided through a combination of the front suspension module 24, the rear suspension module 28 and the lower panel 46. The lower panel 46 adds shear stiffness to the frame 20, while the front and rear suspension modules provide compressive strength and stiffness in the lateral direction.
The passenger compartment module 22 also includes a B pillar 56 extending between the rocker 34 and a roof rail 58. One end of the roof rail is joined to the side rail 32 through an A pillar 60. The other end of the roof rail is connected through a C pillar 62 to the rear portion of the side rail 32. Angled rear window pillars 63 extend between respective C pillars 62 and the rear rail extension 42. Extending between the connections between the roof rail, the A pillar and the C pillar are a windshield header 64 and a backlight header 66, respectively.
The upper rail members 38 have a cowl beam 68 extending between them near the connection between the upper rails 38 and the front hinge pillars 36. A pair of diagonal struts 70 extend on forward diagonals away from the center portion of the cowl beam 68. A pair of diagonal struts 72 extend from the upper rails 38 to the diagonal struts 70. A third set of diagonal struts 73 extend between a front end of the upper rails 38 and the end of diagonal struts 70. All three diagonal struts on each side intersect at a connection point 74.
The entire passenger compartment module 22 preferably is assembled as a complete subassembly before the remainder of the vehicle frame is connected to the passenger compartment module.
The component pieces of the passenger compartment module 22 preferably are made from stainless steel. Stainless steel is the preferred material because of its combined features of being high in strength per unit weight, high in ductility or toughness, and moderate in cost. Other materials such as carbon steel, aluminum or composites could be used in forming a vehicle frame designed according to this invention. In one example, the channel sections, such as rockers 38, the formed panels such as the lower panel 46, and the tubular members such as the roof rail 58 are made from an austenitic stainless steel known as Armco Nitronic 30, preferably cold rolled to 120,000 psi yield strength. The structural members such as side rails 32 preferably have a wall thickness in the range between 1 mm and 2 mm. Relatively large, flat panels and the floor panel 52 preferably have a 1/2 to 1 mm thickness.
The front suspension module 24, as the name suggests, carries the front suspension of the vehicle. A significant advantage of this invention is that an entire front suspension assembly can be assembled onto a completed front suspension module before it is attached to the remainder of the vehicle. This advantage greatly simplifies the manufacturing process and results in economical advantages in reduced operator time and tooling costs. Importantly, the completed front suspension module 24 and the completed front suspension system (not shown) is moved into place and connected to the passenger compartment module from beneath the upper rail members 38. In the prior art, it is not possible to preassemble a complete front suspension system because typical vehicle frames include forwardly extending midrails that do not allow such an assembly procedure. Eliminating a requirement for conventional midrails from the vehicle body is another significant advantage provided by this invention.
The front suspension module 24 includes two suspension towers 80 (best shown in FIG. 5) and a cross car beam 82. A lateral strut 84 is provided for further structural stiffness and to position the front lower ends of the suspension towers 80. A horizontal plate preferably extends between the cross car beam 82 and the lateral strut 84. Alternatively, one or more diagonal braces could be used. A set of diagonal struts 85 extend between the midpoints of the suspension towers 80 and the lateral ends of the cross car beam 82. The suspension towers 80 include a spring mount portion 86, which is designed to accommodate conventional suspension springs and components. The spring mount portion 86 is adjacent a connector 87 that is to be connected to the connection point 74. A bolt preferably extends through the connector 87, the diagonal struts 70, 72, and 73 to complete the connection at that point. The suspension towers are connected to the cross car beam 82 at the mounting members 88. The suspension towers 80 preferably include suspension tower triangular sections 80A and 80B. These triangular sections provide load distribution paths that enhance structural stiffness and strength.
The front suspension module 24 can also be referred to as a subframe portion. The subframe portion 24, which provides support for the vehicle engine and drivetrain, is connected to the passenger compartment module at the connection points 90 to the nodes 44. This connection is illustrated in partial cross section in FIGS. 6. Each of the front and lower nodes 44 includes an extension mounting arm 91. The mounting arm 91 includes a raised conical protrusion 92. An internally threaded mounting boss 94 is formed integrally with the cast node 44. The lower portion (according to the drawing) of the threaded mounting boss 94 has a raised conical protrusion 95. The cross car beam 82 preferably includes a dimple 96 that matingly or nestingly receives the raised conical protrusion 92 and 95, respectively. A bolt 98 is threaded into the interior of the mounting boss 94. A metal bushing 99 is provided through the opening in the cross car beam 82. The bolt 98 most preferably is not threadingly engaged to the opening through the bushing 99 or the cross car beam 82.
The combination of the raised conical protrusion 92 and 95 and the dimple 96 on the cross car beam 82 provide a high strength connection between the cast node 44 (and, therefore, the passenger compartment 22) and the front suspension module 24.
Referring back to FIG. 5, the front energy absorbing module 26 includes a bumper back-up beam 102 and two sets of four energy absorbing tubes 104A, 104B, 104C and 104D. The energy absorbing tubes 104 preferably have a square cross section. One cross strut 106 is provided generally parallel to the bumper back-up beam 102. An upright strut 107 extends between an upper and lower mounting joint 108. The mounting joints 108 are provided for connecting the energy absorbing tubes to the front suspension and passenger compartment modules, respectively. A bolted connection is made at the points labeled 109. The opposite ends of the energy absorbing tubes 104 are connected to the bumper back up bean 102 through mounting joints 108 at connection points 109A and 109B.
The mounting joints 108 ideally are dual pivot, universal joints or a pivot and flexure joint. The joint members 108 preferably are made from stainless steel. An example of a pivot and flexure joint is illustrated in FIG. 7 having two arm portions 158 and 159. One of the arms is coupled to a crash tube 104. The other arm includes a pivot axis 160 that allows movement in one direction. A flex joint or flexure portion 162, which is at the intersection of the arm portions 158 and 159, permits movement in a direction generally perpendicular to the pivot direction. Accordingly, the connection between the energy absorbing tubes 104 and the front suspension and passenger compartment modules provides for movement in two directions.
As a simplification of the above embodiments, a single axis may be defined that would allow flexure during a frontal crash. Moderate deviations from a direct frontal crash typically can be accommodated by the ductility of the metal so that a two-directional movement at the mounting joint is not always necessary.
The presently preferred embodiment includes a mounting joint 108 as illustrated in FIG. 8. The mounting joint 108 includes a generally flat plate portion 210 and two tube mounts 212 and 214. The tube mount 212 includes an arm portion 216 that is coincident with a flare portion 217 and extends between the plate portion 210 and a flexure portion 218. A tube receiving arm 220 extends from the flexure portion 218 in a direction opposite from the arm portion 216. The energy absorbing tubes preferably are attached to the tube receiving arms by a plurality of spot welds 221. The flexure portion 218 provides for a deformation of the tube mount 212 in the event of an impact force on the bumper back-up beam 102, for example. Depending on the direction of the impact force, the impact absorbing tube 104B can pivot relative to the plate portion 210 as the flexure portion 218 responsively deforms so that the arm 220 pivots relative to the remainder of the mounting joint 108. Similarly, the tube mount 214 includes a first arm portion 222, a flexure portion 224 and a tube receiving arm portion 226.
The plate portion 210 preferably is bolted to an appropriate connection point 109 on the vehicle frame. Specifically, the plate portions of the upper mounting joints preferably are bolted to the connection points 109 on the upper rail members 38 and the plate portions of the lower mounting joints preferably are bolted to the connection points 109 at a lower front end of the suspension module 24. The bolted connection is made through an opening 228 and preferably is set so that the plate portion 210 remains fixed relative to the connection point 109.
The connection points 109A (see FIG. 5) preferably include mounting joints 108 as illustrated in FIG. 8 because the ends of two tubes 104 are placed in close proximity to each other. At the mounting points 109B (FIG. 5), the joints 108 are slightly modified. As can be seen in the figure, the forward ends of the two tubes 104B and 104D are spaced apart. Therefore, the plate portion 210 and the flare portion 217 are elongated so that the tube receiving arms are spaced accordingly. Otherwise the mounting joints are the same as already described.
As best seen on the tube receiving arm portion 226 the mounting joint tube receiving arms include four perpendicularly oriented fin portions 230, 232, 234 and 236. FIG. 9 illustrates a preferred embodiment of the energy absorbing tubes 104. Each end of the tubes 104 includes four generally perpendicularly oriented channels 238, 240, 242 and 246. The fin portions on the mounting joint 108 are received within the channels on the tubes 104 as illustrated in FIG. 8, for example.
The energy absorbing tubes 104 as illustrated in FIG. 9 are configured for use with mounting joints as illustrated in FIGS. 5 and 8 while still maintaining the desirable energy absorbing characteristics described below. The generally square cross section illustrated in FIG. 10 is maintained along a substantial portion of the length of the energy absorbing tubes 104.
It is most advantageous to mount the energy absorbing tubes 104 in an arrangement generally as illustrated such that an impact force to the front of the vehicle is transmitted axially along the crash tubes 104. A direct or true axial load causes the square cross-sectioned tubes 104 to deform in a predictable fashion. Specifically, the tubes will fold upon themselves in a stacking pattern so long as the load remains as close to truly axial as practical. As can be appreciated from the drawings, as the bumper back-up beam 102 moves toward the passenger compartment 22, the energy absorbing tubes 104 should move generally inward. That is, the top energy absorbing tubes 104A and 104B ideally will move inward and downward according to the drawing, while the energy absorbing tubes 104D and 104C will move inward and upward according to the drawing.
The mounting joints 108 permit pivoting or flexing as described above to allow the energy absorbing tubes 104 to move in a manner that resembles the ideal pattern just described. The energy absorbing tubes 104 can pivot because of the flexure portions 218 and 224. Such pivotal movement permits the tubes 104 to move in a pattern that resembles the ideal pattern. Therefore, the mounting joints 108 facilitate maintaining an axial load on the tubes 104.
Providing a predictable deformation pattern of the energy absorbing tubes 104 significantly absorbs the energy from an impact or collision. Otherwise, unpredictable deformations may result in leftover energy which must be absorbed by the passenger compartment, which is not always desirable. An energy absorbing module 26 designed and mounted according to this invention provides significant structural and passenger safety advantages.
As best shown in FIG. 11, the rear suspension module 28 includes two suspension towers 110. A lateral strut 112 extends between the lower rear ends of the suspension towers. A pair of diagonal struts 114 are connected to the tower 110 and the lateral strut 114. A cross car beam 116 is included that is essentially the same as cross car beam 82. A horizontal plate preferably extends between the cross car beam 116 and the lateral strut 114. Two diagonal struts 117 extend between the front lateral edge of the cross car beam 116 and a midpoint on the front of the suspension towers 110.
The suspension towers 110, like their counterparts the suspension towers 80 of the front suspension module 24, are adapted to support a completed rear suspension assembly. Most preferably, the entire suspension assembly is assembled with a completed rear suspension module 28 and then that entire unit is mounted onto the rear of the passenger compartment module 22. The mounting point 118, which is for connection to nodes 44, is the same as that described with respect to the front suspension module and, therefore, need not be further described here. The mounting points 120 are similar to those at the connection points 74 for the front suspension module. A triangular arrangement 121 of the end rail portions 42 and struts 121A and 121B is provided at each side of the frame near the rear end of the passenger compartment. The triangular struts provide structure for the suspension towers 110 to be supported on the second end rail portions 42.
The rear energy absorbing module 30 includes a bumper back-up beam 122 and two sets of energy absorbing tubes 124A, 124B and 124C. A strut 126 is provided at each lateral end of the module 30. The connection points 128 and 130 preferably include mounting joints as diagrammatically illustrated in FIG. 8 and described above with respect to the front energy absorbing module 26. The mounting joints at 129 are different because there is no requirement for two tubes to end adjacent each other. The mounting joint includes only one tube receiving arm portion. Otherwise, the configuration and function of the mounting joint at 129 is the same as described above. The connection of the rear energy absorbing module 30 to the passenger compartment module 22 and the rear suspension module 28 is accomplished at the points 127 and is similar to that of the front energy absorbing module and, therefore, need not be further described.
Referring now to FIG. 12, at least the lower four cast nodes 44 include a triangular arrangement 132 of load paths 134. The load paths 134 essentially are legs of the triangle 132. Importantly, the load paths, or legs 134, intersect at nodes 138.
The cast nodes 44 preferably are integrally formed from a casting process. The known Hitchner or FM processes can be used, for example. The preferred material for the cast nodes 44 is a stainless steel alloy. A variety of materials are available, however, in one example, the preferred material is Armco Nitronic 19D, which is a duplex stainless steel. The thickness of the casting preferably is approximately 3-4 mm.
The cast nodes 44 are connected to the channel section beam members such as the rockers 34 and the front hinge pillars 36. Protruding away from the triangular arrangement 132 in perpendicular directions are insert tabs 140. The insert tabs 140 are received within roll formed channel sections on the arms 142 of the channel members. A flange 144 overlaps a web portion 146 of the channel members. The insert tabs 140 are welded to the roll formed channel sections on the arms 142 by a conventional spot welding or laser welding technique. Spot welds are shown at 147. Similarly, the flange 144 is welded to the web portion 146.
Although the spacing within the triangle 132 is open after the casting process, it preferably is capped, plugged or filled when the node 44 is incorporated into a complete frame 20. Those skilled in the art will be able to choose an appropriate cap or filler so that there is no leak through the node piece 44.
As can be seen, the load paths 134 provide a path for changing the direction of forces or loads imposed on the channel members of the side rails. For example, a load in the direction of force arrow 148 along the arm portion 142 is redirected along one of the load paths 134 as shown by the arrow 150. Accordingly, shear stresses and impact forces or loads that otherwise would cause fractures or severe deformation in the vehicle frame are dissipated and effectively reduced by the redirection of the load along one of the load paths 134. Accordingly, cast nodes 44 designed according to this invention provide structural integrity along with enhanced structural stability in the event of a collision or impact.
The foregoing description is exemplary rather than limiting in nature. Variations and modifications of the preferred embodiment will become apparent to those skilled in the art that do not depart from the purview and spirit of this invention. Accordingly, the appended claims must be studied to determine the legal scope of protection accorded this invention. | A connector piece useful for joining two beam members preferably includes a generally triangular arrangement of load bearing members. The connector piece is especially useful in joining beam members of a vehicle space frame. The connector piece includes a set of tab members extending generally away from the load bearing members. The tab members are inserted into channels formed on the beam members. The beam members are then joined to the connector piece, preferably, by spot welding through each sidewall of the channels and the tabs, respectively. A longitudinal component of a load incident on one of the beam members is transferred along at least one of the load bearing members to assist in avoiding deformation of the beam. | 8 |
[0001] This application is a Continuation-In-Part of application Ser. No. 10/432,208 filed May 20, 2003 which claims priority to PCT patent application number PCT/US01/49310 filed on Dec. 20, 2001 which claims priority to application No. 60/258,208 filed Dec. 27, 2000.
FIELD OF THE INVENTION
[0002] The field of the invention is waste disinfection.
BACKGROUND
[0003] Fluid organic waste typically contains a high degree of microorganisms. Much of this waste is disposed of into waterways through sewers and into the ground through septic tanks, leach lines and so on. In any case, the microorganisms ultimately infect our potable water causing it to become unhealthy for consumption.
[0004] In some instances steps are taken to disinfect the fluid waste before disposal. Many disinfection systems use chemicals to kill some of the microorganisms, but these systems are relatively ineffective because the fluid waste is so highly contaminated to begin with. There are, however, disinfection systems that attempt to separate components of the waste and to dispose of the more contaminated products in a different way than the less contaminated components. U.S. Pat. No. 6,284,054, for example, teaches a system in which solid animal waste is separated from waste water using electrocoagulation. Thereafter, the solid waste is disposed of using incineration or other methods while the waste water is purified and then recycled.
[0005] Methods of purification and disinfection often utilize can also utilize filters, reverse osmosis, ion exchange and even ultraviolet waves. Some of these methods, however, have proven to be relatively ineffective in terms of removing a high percentage of microorganisms while others are problematic due to clogging and high expense.
[0006] Ion exchange and ultraviolet systems generally work well, however, it is desirable to be able to produce small cluster water defined herein to mean a size of only 5-6 water molecules per cluster, and these methods are not effective at producing such results. Small cluster water is reported to have numerous useful characteristics. Among other things, small cluster water is said to provide: improved taste of foods; accelerated absorption of drugs and food through the digestive tract; and prevention of cancer due to reduced production of mutagens in the intestines and reduced activity of enteric microorganisms and digestive tract tissue cells. See U.S. Pat. No. 5,824,353 to Tsunoda et al. (October 1998). Tsunoda et al. and all other publications identified herein are incorporated by reference in their entirety.
[0007] In producing small cluster water, electrical, magnetic, chemical, and acoustical methods have all been utilized. Electrical and magnetic methods typically involve running water past closely spaced electrodes. Examples are set forth in U.S. Pat. No. 5,387,324 (February 1995) and U.S. Pat. No. 6,165,339 (December 2000), both to Ibbott. Usually field strength is adjusted by moving the electrodes or magnets with respect to one another. See, e.g., U.S. Pat. No. 5,866,010 to Bogatin et al. (February 1999). In other instances field strength is adjusted by altering the path of the water. See e.g. U.S. Pat. No. 5,656,171 to Strachwitz (August 1997), which describes curved piping through magnetic field. U.S. Pat. No. 6,033,678 (March 2000) and U.S. Pat. No. 5,711,950 (January 1998) both to Lorenzen, describe production of reduced cluster water by passing steam across a magnetic field.
[0008] Chemical methods typically involve adding electrolytes and polar compounds. The U.S. Pat. No. 5,824,353 patent to Tsunoda, et al. teaches production of reduced cluster size water using a potassium ion concentration of 100 ppm or more, and containing potassium ions, magnesium ions and calcium ions in a weight ratio of potassium ions:magnesium ions:calcium ions of 1: 0.3-4.5:0.5-8.5. Other chemical methods include use of surfactants, and clathrating structures that cause inclusion of one kind of molecules in cavities or lattice of another. See U.S. Pat. No. 5,997,590 to Johnson et al. (issued December 1999).
[0009] Acoustical methods typically involve subjection of water to supersonic sound waves. See U.S. Pat. No. 5,997,590 to Johnson et al. (issued December 1999).
[0010] A Japanese company currently sells a water purifying system that is said to produce water having cluster size of 5-6 molecules. The system, marketed under the name Microwater™, passes tap water past electrodes. Water passing closer to a positive electrode tends to become acidic. The company's literature reports that the acidic water (termed oxidized or hyperoxidized water) is said to be useful as an oxidizing agent to sterilize cutting boards and treat minor wounds. Other suggested uses are treating athlete's foot, minor burns, insect bites, scratches, bedsores and post-operative wounds. The company's literature also reports that the acidic water has been used agriculturally to kill fungi and other plant diseases. Water passing closer to a negative electrode tends to become alkaline. The alkaline water (termed reduced water) is said to be beneficial when taken internally. Such water is said to inhibit excessive fermentation in the digestive tract by indirectly reducing metabolites such as hydrogen sulfide, ammonia, histamines, indoles, phenols, and scatols.
[0011] U.S. Pat. No. 5,624,544 to Deguchi et al. (April 1997) describes such a system. Deguchi et al. Claim that oxidizing streams down to pH 4.5 and reducing streams up to pH 9.5 can be achieved on a continuous basis, but that waters having pH 2.5 to 3.2 or pH 11.5 to 12.5 cannot be produced continuously for a long period. It is thought that these limitations are due to the known methods and apparatus being incapable of efficiently reducing the cluster size below about 4 molecules per cluster.
[0012] Thus, there is still a need to provide methods and apparatus for dispensing potable liquids that can continuously produce substantial quantities of water having little or no bacteria, having cluster sizes below about 4 molecules per cluster, and all without substantially changing the pH. Water having these characteristics is thought to be more healthy than other water.
SUMMARY OF THE INVENTION
[0013] The present invention provides methods and apparatus for treating fluid waste with an RF plasma generator. The fluid waste, usually including waste water, is carried past the waves with a conduit. In a preferred class of embodiments, the system is inline downstream of a toilet. In another aspect, the RF plasma can be housed within a sewer system or in a sanitary fixture.
[0014] Methods of reducing biological contamination in waste include the steps of providing an RF plasma wave generator, and carrying the waste past waves produced by the generator under conditions that inactivate or kills a substantial percentage of the microbe content in the waste. Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is a cross sectional view of a system for treating a fluid waste.
DETAILED DESCRIPTION
[0016] Referring first to FIG. 1, a system for treating a fluid waste generally comprises a source of waste 110 , a waste line 120 , a holding tank 130 , a conduit 140 , an RF plasma generator 150 , and an body including treated waste 160 .
[0017] Fluid waste encompasses any substantially organic fluid that is in need of disposal such as the waste from the human body and unwanted food. While fluid waste is likely to comprise at least some solid and semi-solid compositions, the solid and semi-solid compositions are insubstantial enough such that the waste is still able to flow through a conduit. In some cases, the assistance of a pump or similar device may be used to push or pull the waste through the conduit.
[0018] Fluid waste generally flows into a waste line 120 (e.g. a pipe from a toilet or a sink disposal) and then into a sewer or a holding tank such as a septic tank for a home or a holding tank of a vehicle. Ships, recreation vehicles, and airplanes are good examples of vehicles that have holding tanks. Holding tank 130 has an input 132 and an output 134 . Fluid waste flows into the holding tank 130 through one-way input valve 132 . Fluid waste presumably contaminated with a high content microorganisms can be held in a tank for hours, days, or more.
[0019] Upon release of the fluid waste from the tank through one-way output valve 134 , the waste flows into conduit 140 where it is carried past the waves of the RF plasma generator 150 . It should be noted that waste can be carried past the waves in at least two substantially separate streams (i.e. a basic stream and an acidic stream) and then recombined after being subjected to the waves. The basic frequency of the plasma is preferably between 0.44 MHz and 40.68 MHz, and the plasma is preferably modulated at a frequency between 10 kHz and 34 kHz. Flow rates typically range from 20 1/hr to about 2000 1/hr, although multiple configurations and sizes of device are also contemplated, so that lower and higher flow rates are possible.
[0020] Conduit 140 is preferred to be a pipe or series of pipes that accepts fluid waste from a holding tank or directly from a source of fluid waste. The conduit, which is substantially water tight, carries the fluid waste past the waves allowing it to be subjected to the waves for an amount of time that is sufficient to inactivate or kill a substantial amount of the microorganisms in the waste. A substantial amount is considered to be 50% although preferred embodiments kill or inactivate over 90%.
[0021] Plasmas are conductive assemblies of charged particles, neutrals and fields that exhibit collective effects. Plasma generator 150 is preferably a “cold” type plasma device, which term is used herein to mean a gas of ionized atoms cooler than 10,000° K. With the plasma generator 150 in operation, a stream of fluid waste enters the conduit 140 at output 134 , flows through the conduit 140 , and exits through outlet 142 . It should be noted that multiple inputs and multiple online sources are also contemplated. Moreover, the conduit may accept input from multiple sources.
[0022] The RF plasma generator is generally located downstream of a sanitary fixture but may even be located in the fixture itself. In other contemplated embodiments, an RF plasma is in the waste line, in the holding tank, or anywhere else upstream of the treated waste discharge. Specific aspects of an RF plasma wave generator are taught in pending U.S. patent application Ser. No. 10/432,208 incorporated by reference in its entirety.
[0023] It is contemplated that the fluid waste may be separated at some point before being subjected to the waves. In embodiments that separate the waste, a portion of the waste may be diverted from contact with the waves of the RF plasma. Alternatively, portions of the waste may be subjected to the waves in succession (i.e. separately) thereby allowing for different settings to be used on different types of waste. For example, substantially solid waste can be subjected to lower frequency waves than waves that are substantially liquid. The treated waste can be discharged into a body 160 such as a lake, ocean, the ground, municipal waste treatment plant and so on. In any case, biological contamination by parasites (e.g schistosoma), protozoa (e.g cryptosporidium parvum ), bacteria (e.g. cholera), viruses (e.g. hepatitis A), and/or metals, perchlorates and other abiotic substances is substantially reduced by exposure to the RF plasma waves. Methods of reducing 50%, 90%, or more of the microbes include the step of carrying the waste past waves produced under conditions that inactivate or kill the microbes. In generating waves using an RF plasma generator, the RF plasma generator is operated within the ranges outlined above. The waves from the RF plasma come in contact with the fluid waste thereby producing treated water. It may be desirable to further treat the treated water by subjecting the treated water to filtering, reverse osmosis, and so on. Additionally, it may be advantageous to combine additional chemicals with the treated water prior to dispensing.
[0024] Those skilled in the art will recognize that the device of FIG. 1 can be scaled up or down. For example, the device of FIG. 1 can alternatively be viewed as having multiple sources of waste and multiple waste lines, conduit, tanks, and even wave generators.
[0025] Thus, specific embodiments and applications directed toward treating a fluid waste have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. | An apparatus subjects fluid waste to waves from an RF plasma. This allows continuous production of “activated water” characterized by cluster sizes below about 4 molecules per cluster, water having pH below 4 or above 10, or water having ORP of less than −350 mV or more than +800 mV. The basic frequency of the plasma is preferably between 0.44 MHz and 40.68 MHz, and the plasma is preferably modulated at a frequency between 10 kHz and 34 kHz. Flow rates typically range from 20 1/hr to about 2000 1 hr. | 2 |
FIELD OF THE INVENTION
The present invention relates to an improved process for the production of Zirconium Boride Powder.
BACKGROUND OF THE INVENTION
Zirconium boride/diboride is emerging as a potential advanced ceramic because of it's excellent properties—high melting point, hardness, elastic modulus and electrical conductivity, resistance to acids like HCL, HF and other non-ferrous metals, cryolite and non-basic slags. Due to these properties, ZrB 2 finds several engineering applications like cathodes for electrochemical processing of aluminum (Hall-Heroult process), evaporation boats, crucibles for handling molten metals, thermowells, wear parts, nozzles, armor and as dispersoid in metal and ceramic composites for getting improved mechanical properties, cutting tools etc. It is also used as thermocouple sieves for high temperature furnaces.
Zirconium Boride due to its several technological important uses, as stated above, has been synthesized in the prior art in several ways:
1. Synthesis from elements by melting, sintering or hot pressing in the process.
Zirconium and boron metal ingots are melted together in inert atmosphere in furnace to obtain a final product in the form of lumps of zirconium boride. Metallurgical processes such as forging, milling are used to obtain fine powder of zirconium boride. The process uses raw material in elemental form. Therefore different powder metallurgy processing methods are required for converting from elemental to powder form. Thus the process becomes very costly and so commercially may not be viable.
2. Borothermic reduction of metal oxides
In this method, zirconium oxide is reduced using boron metal powder in furnace under inert atmosphere, represented by the following equation.
ZrO 2 +2B=ZrB 2 +O 2
The use of pure boron in the process makes it costly. Another disadvantage is that the efficiency of conversion is generally not very high.
3. Another known process uses carbothermic reduction of metal-oxides and boric oxide to produce zirconium boride powder and can be represented by the following equation
ZrO 2 +B 2 O 3 +5C=ZrB 2 +5CO
4. In another know process, reduction of the metal oxide is done with carbon or Boron carbide, the reaction being represented by the equation.
2ZrO 2 +B 4 C+3C=2ZrB 2 +4CO
The above mentioned processes 3 and 4 , generally do not result to pure ZrB 2 powder. Also reduction of ZrO 2 by boron carbide and carbon requires very high temperature furnaces in the range of about 2000 to 2200° C., which makes the process costly and much more time consuming.
5. Another known process is aluminothermic, magnetiothermic and ilicothermic reduction of metal oxide—Boric Oxide mixture to produce zirconium boride powder.
In this process, mixture of oxides of zirconium and boron is coeduced using low melting metal powders of aluminum, magnesium or silicon in furnace, which is represented by the following equation
ZrO 2 +B 2 O 3 +5Mg=ZrB 2 +5MgO
Here though the reduction is done at relatively low temperature, but for high purity products further treatment at higher temperature is required. Also since zirconium oxide is a very stable oxide due to its low free energy it is difficult to reduce it completely without going to high temperature and hence the final product usually retains some amount of ZrO 2 with zirconium boride and magnesium oxide or other metal oxide. It is difficult to remove ZrO 2 with etchants because etchants which can dissolve ZrO 2 also dissolve zirconium boride. Hence zirconium boride also pass into the solution.
6. Self propagating high temperature synthesis (SHS) synthesis of Zirconium boride by elemental powder.
The SHS process is in exploitation of a highly exothermic and usually very rapid chemical reaction to form an useful material. The central feature of the process is that the heat required to drive the chemical reaction is supplied from the reaction itself. The potential commercial attractiveness of the SHS derives from the expected lower capital and operating costs. The SHS has found applications in recent year for preparing intermetallics and advanced high temperature materials such as carbides, borides, slicides and nitrides (A. G. Mershanov and I. P. borovinskaya, Combat. Sci. Technol. 10, 195 (1975), I. M. Sheppard, Adv. Mater. Proce, 25, (1986). Applications, advantages, fundamental and technological aspects of SHS have been reviewed in literature [Z. A. Munir, Meatall, Trans. A, 23A, 7 (1992), A Makino, C. K. Low, J. Amer, Corm. Soc. 77(3), 778 (1994). This technique has inherent advantages over conventional methods, which require high temperature furnaces and longer processing times. Materials produced by the SHS method have advantages such as high purity of product [B. Manaly, J. P. Holt and Z. A. Munir, mat. Sci. Res., 16. 303 (1984), low energy requirements and relatives simplicity of the process (H. C. Yi and J. J. Moore, J. Mat, Sci., 25, 1150 (1990)]. Owing to the high cooling rate, high defect concentrations and non-equilibrium structures exist in the SHS produced materials, resulting in more reactive metastable and thus more sinterable products [O. R. Bermann and J. Barrington, J. Amer. Cerm. Soc., 49, 502 (1966).
In the SHS of zirconium boride, zirconium and boron metal powders are mixed together and ignited from top. The ignition source is switched off as the surface reaches the required ignition temperature. The combustion wave now propagates throughout the sample. Reaction rates has been calculated as 25 centimeter per second as reported in literature.
Even though the SHS process has advantages but use of element powder makes the process cost incentive.
Hence it is observed that in all the above known processes, the time requirement is more and also it requires high temperature furnace in the range of 2000 to 2200° C. to achieve 99% and above pure products or it does require pure elemental powders as starting raw material which make the process costly.
OBJECTS OF THE INVENTION
The main object of the invention is to provide an improved process for the production of pure zirconium boride powder.
Another object of the invention is to provide an improved process for the production of zirconium powder which is cost effective, fast and energy efficient.
Yet another object of the invention is to provide a process which makes use of self-propagating high temperature synthesis where the starting materials are zirconium chloride and boric acid.
Still another object of the invention is to synthesize pure single phasic zirconium diboride where no other peaks are detected through XRD, at room temperature without using any high temperature furnaces at a low processing time.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides an improved process for the production of zirconium boride, which comprises mixing powders of zirconium chloride in the range of 20-25% wt, Boric acid (H 3 BO 3 ) in the range of 35-44 wt % and small cut turnings Magnesium (Mg) in the range of 33-40 wt % and pelletising the mixture so prepared, igniting the prepared pellets under inert atmosphere and leaching the resultant product (ZrB 2 and MgO) with leachant to obtain zirconium boride.
In one embodiment of the invention, zirconium chloride and boric acid are milled prior to mixing.
In another embodiment of the invention, the resulting mixture after ignition is leached with a leachant comprising phosphoric acid.
In another embodiment of the invention., the zirconium chloride, boric acid and magnesium used as raw materials are of commercial grade.
In another embodiment of the invention, the reaction time is in the range of 1 to 2 minutes.
In another embodiment of the invention., the product zirconium boride is of purity of 95% and above.
DETAILED DESCRIPTION OF THE INVENTION
In the process of present invention, due to reaction between boric acid, Zirconium compound and magnesium, the temperature rises and as soon they are reduced to metal further rise of temperature takes place of the order of 2500° C. due to the reaction between zirconium and boron. Since zirconium chloride can be reduced at much lower temperature compared to zirconium oxide owing to higher free energy of zirconium chloride at reaction front, the product is free from ZrO 2 . The product has only ZrB 2 and MgO. MgO is further selectively leached out using suitable leachant such as ortho phosphoric acid and the like. The processing time is also less to the range of 1-2 minute.
By the process of present invention more then 95% purity of zirconium boride is produced using zirconium chloride, boric acid and magnesium turning. The invention takes much lesser time compared to other available known processes.
The following examples are given by way, of illustrations and should not be construed to limit the scope of the invention
EXAMPLE 1
ZrCl 4 =2 gms
Mg=3.5 gms
H 3 BO 3 =4 gms
The above-mentioned materials were milled for proper mixing. The mixture was pelletised into 15 mm die cylinder of height 25 mm. Pellets were kept in a reaction chamber, in argon atmosphere in a graphite crucible. Pellets were arc ignited using graphite electrode. The reaction was complete in 30 seconds. Product was leached with 20% strength phosphoric acid solution in water.
Result: It was found that product has ZrB 2 as main phase. MgO, Mg 3 (BO 3 ) 2 and Magnesium boride were also present in the product. After leaching product has ZrB 2 and magnesium boride. So an attempt was made to reduce Mg and boric acid to some extent. Hence other amounts (Lesser amounts of Mg and H 3 BO 3 were also tried.)
EXAMPLE 2
ZrCl 4 =2 gms
Mg=3 gms
H 3 BO 3 =3.5 gms
All the above materials were milled for proper mixing The mixture was pelletised into 15 mm diameter cylinder of height 25 mm. Pellets were kept in a reaction chamber in argon atmosphere in a graphite crucible. Pellets were arc ignited using graphite electrode. The reaction was complete in 30 seconds. Product was leached with 20% strength phosphoric acid solution in water.
Result: Here the amounts of Mg and boric acid was varied. It was found that quality of the product improved with ZrB 2 as main phase and MgO, Mg 3 (BO 3 ) 2 and Magnesium boride were also present in the product. After leaching product has ZrB 2 and still some magnesium boride, so we felt that Mg and boric acid should be further reduced to some extent. Hence other amounts of Mg and H 3 BO 3 were also tried.
EXAMPLE 3
ZrCl 4 =2 gms
Mg=3 gms
H 3 BO 3 =3 gms
All above materials were milled for four hours for proper mixing. The mixture was pelletised into 15 mm diameter cylinder of height 25 mm. Pellets were kept in a reaction chamber in argon atmosphere in a graphite crucible. Pellets were arc ignited using graphite electrode. The reaction was complete in 30 seconds. Product was leached with 20% strength phosphsphoric acid solution in water.
Result: Here the product has ZrB 2 and MgO with almost negligible amount of Mg3 (BO 3 ) 2 . After leaching with phosphoric acid only zirconium diboride peaks were detected through XRD.
EXAMPLE 4
ZrCl 4 =10 gms
Mg=15 gms
H 3 BO 3 =15 gms
All above materials were milled for four hours for proper mixing. The mixture was pelletised into 15 mm diameter cylinder of height 25 mm. Pellet were kept in a reaction chamber in argon atmosphere in a graphite crucible. Pellets were arc ignited using graphite electrode. The reaction was complete in 30 seconds. Product was leached with 20% strength phosphoric acid solution in water.
Result: Here the product has ZrB 2 and MgO with almost negligible amount of Mg 3 (BO 3 ) 2 . After leaching with phosphoric acid only Zirconium Diboride peaks were detected through XRD.
Main Advantages of the Present Invention are:
1. The present invention uses cheaper raw materials viz. zirconium chloride, boric acid and magnesium turnings compared to elemental zirconium and boron used by the known processes.
2. The present invention does not require any high temperature furnace as used by the known processes.
3. The present invention time consumption is very less compared to other known process.
4. The present invention is cost and energy effective compared to known processes. | The present invention provides an improved process for the manufacture of zirconium boride by reacting boric acid, a Zirconium compound and magnesium and leaching the resulting product mixture to obtain zirconium boride with high purity. | 2 |
TECHNICAL FIELD
[0001] The present invention relates to flow measuring apparatuses to measure the flow of fluid, and particularly relates to airflow measuring apparatuses that are suitable for intake airflow of an internal combustion engine for automobile.
BACKGROUND ART
[0002] Conventionally heat-generation type airflow sensors are becoming the mainstream to measure the intake airflow, which are installed in an intake air passage of an internal combustion engine in automobile or the like, because such a type of sensor can detect mass airflow.
[0003] A sensor element can be formed as a thinner film partially by a semiconductor micromachining technique, whereby the airflow sensor can have high-speed responsivity. Hereinafter this thin-film part is called a diaphragm. On the diaphragm, a heating resistor and two or more thermosensitive resistors adjacent to the heating resistor are formed by patterning. The heating resistor is uniformly controlled to generate heat to be at a predetermined temperature or higher than the surrounding temperature, and the temperature distribution thereof is detected by the thermosensitive resistors. Since the temperature distribution changes with the amount of airflow passing over the sensor element, the variation in temperature distribution is detected by the thermosensitive resistors disposed upstream and downstream of the airflow direction, whereby the mass airflow can be measured.
[0004] As means for such a heat-generation type airflow meter using a sensor element, the sensor element and a lead frame to mount the sensor element thereon are surrounded with resin as a package by transfer molding, for example.
[0005] This is for reducing the number of components or the number of connections compared with the structure including a sensor element and a circuit mounted on a substrate made of ceramic or the like.
[0006] Such a sensor element and the thermal flow meter including such a packaged sensor element have the following problems.
[0007] To begin with, when stress is applied to the heating resistor and the thermosensitive resistors disposed on the diaphragm, their values of resistance change due to Piezoresistive effect, which becomes an erroneous cause of the mass airflow detected. If a pressure difference occurs between the surface and the rear face of the diaphragm part, the diaphragm part is deformed, so that stress is applied to the heating resistor and the thermosensitive resistors. To avoid this, there is a need to suppress such a pressure difference between the surface and the rear face of the diaphragm part.
[0008] As a method to reduce the pressure difference between the surface and the rear face of the diaphragm, Patent Literature 1 provides an opening at the surface of a diaphragm or at the rear face of a substrate to mount a sensor element thereon for communication between a cavity at the rear face of the diaphragm and the atmospheric pressure at the surface of the diaphragm.
CITATION LIST
Patent Literature
[0000]
Patent Literature 1: JP 2008-20193 A
SUMMARY OF INVENTION
Technical Problem
[0010] The method described in Patent Literature 1, however, cannot avoid contaminants or droplet completely from entering through the opening at the surface of the diaphragm or on the side of the rear face of the substrate to support the diaphragm, because the opening is exposed to the interior of the intake pipe.
[0011] When the sensor element is mounted on a lead frame, followed by packaging by transfer molding, the cavity part at the rear face of the diaphragm will be completely cut off from the air. This means that, if the surrounding temperature of the chip package changes, the volume of the air in the cavity at the rear face of the diaphragm changes, and so a difference in pressure between the atmospheric pressure applied to the surface of the diaphragm and the air pressure at the rear face of the diaphragm deforms the diaphragm. This deformation changes the values of resistance of the heating resistor and the thermosensitive resistors on the diaphragm change due to Piezoresistive effect, thus generating an error in the mass airflow detected.
[0012] In this way, there is a need to establish a communication between the space at the rear face of the diaphragm part and the atmosphere to remove a difference in air pressure between the surface and the rear face of the diaphragm due to the influences from temperature.
[0013] On the diaphragm, a heating resistor is disposed to detect the flow, and water droplet or contaminations in the intake pipe will fly to the diaphragm part as stated above. Although an opening has to be bored to remove the difference in air pressure so as to lead the space at the rear face of the diaphragm part to any part of the thermal airflow meter, if such an opening is bored at the position that is exposed to the interior of the intake pipe, contaminations or water droplet reaching the opening may block the opening.
[0014] There is another problem of displacement of the mounting position of the sensor element. As stated above, the temperature distribution generated by a heater is based on the detection of the flow rate of air passing over its surface. Since the flow-rate distribution in a bypass-passage to mount a sensor element is not uniform, the displacement of the sensor element mounted causes a change in the flow detected by such a sensor element, meaning that the mass airflow cannot be measured correctly. To prevent this, there is a need to mount a sensor element precisely in the package.
[0015] It is an object of the present invention to provide an airflow measuring apparatus with good measurement accuracy.
Solution to Problem
[0016] To fulfill the above object, an airflow measuring apparatus of the present invention includes: a sub-passage that takes in a part of a flow of fluid flowing through an intake pipe; a sensor element that is disposed in the sub-passage to measure the flow of fluid; a circuit part that converts the flow of fluid detected by the sensor element into an electric signal; a connector part having a connector that is electrically connected to the circuit part to output a signal externally; and a casing that supports the sensor element and the circuit part, the sensor element being disposed in the intake pipe. The sensor element includes a cavity that is disposed at a semiconductor substrate, and a diaphragm including a thin film part that covers the cavity. The sensor element is mounted at a lead frame. The sensor element and the lead frame have surfaces that are mold-packaged with resin so that a diaphragm part of the sensor element and a part of the lead frame are exposed. At least one hole is disposed at the lead frame for communication between the cavity and exterior of the mold package.
Advantageous Effects of Invention
[0017] The present invention can provide an airflow measuring apparatus with good measurement accuracy.
BRIEF DESCRIPTION OF DRAWINGS
[0018] FIG. 1 illustrates the state to mount a thermal airflow meter to an intake pipe.
[0019] FIG. 2 illustrates the structure of a thermal airflow meter and its components.
[0020] FIG. 3 illustrates a detection part of a sensor element.
[0021] FIG. 4 includes a plan view and a cross sectional view of a chip package that is Embodiment 1.
[0022] FIG. 5 includes a plan view and a cross sectional view (1) illustrating the shapes of a cover frame, adhesive and a lead frame that are components of a lead frame assembly that is Embodiment 1.
[0023] FIG. 6 includes a plan view and a cross sectional view illustrating a step of Embodiment 1 in the state where a cover frame is mounted.
[0024] FIG. 7 includes a plan view and a cross sectional view illustrating a step of Embodiment 1 in the state where a sensor element is mounted at a lead frame assembly.
[0025] FIG. 8 includes a plan view and a cross sectional view illustrating a step of Embodiment 1 after transfer molding.
[0026] FIG. 9 includes a plan view and a cross sectional view (1) illustrating the shapes of a cover frame, adhesive and a lead frame that are components of a lead frame assembly that is Embodiment 2, which is one alternative proposal for Embodiment 1.
[0027] FIG. 10 includes a plan view and a cross sectional view (2) illustrating the shapes of a cover frame, adhesive and a lead frame that are components of a lead frame assembly that is Embodiment 3, which is another alternative proposal for Embodiment 1.
[0028] FIG. 11 illustrates Embodiment 4, illustrating a cutting part of an outer lead including a communication hole.
[0029] FIG. 12 is an enlarged view of a cut end of an outer lead cutting part including a communication hole.
[0030] FIG. 13 illustrates an alternative proposal to mount a plurality of chips and an alternative proposal to improve the connection reliability at a cutting part.
[0031] FIG. 14 includes a plan view and a cross sectional view illustrating the shapes of a cover frame, adhesive and a lead frame that are components of a lead frame assembly that is Embodiment 8.
[0032] FIG. 15 includes a plan view and a cross sectional view illustrating a step of Embodiment 8 in the state where a cover frame is mounted.
[0033] FIG. 16 includes a plan view and a cross sectional view illustrating a step of Embodiment 8 in the state where a sensor element is mounted at a lead frame assembly.
[0034] FIG. 17 includes a plan view and a cross sectional view (1) illustrating the shapes of a cover frame, adhesive and a lead frame that are components of a lead frame assembly that is Embodiment 9, which is one alternative proposal for Embodiment 1.
[0035] FIG. 18 includes a plan view and a cross sectional view (2) illustrating the shapes of a cover frame, adhesive and a lead frame that are components of a lead frame assembly that is Embodiment 10, which is another alternative proposal for Embodiment 1.
[0036] FIG. 19 illustrates an alternative proposal to form a communication groove by pressing by bending a lead frame that is Embodiment 11.
[0037] FIG. 20 illustrates the alternative proposal to form a communication groove by pressing by bending a lead frame that is Embodiment 11.
[0038] FIG. 21 illustrates another alternative proposal to form a communication groove by etching by bending a lead frame that is Embodiment 11.
[0039] FIG. 22 illustrates the alternative proposal to form a communication groove by etching by bending a lead frame that is Embodiment 11.
[0040] FIG. 23 includes a plan view and a cross sectional view illustrating the shapes of a cover frame, adhesive and a lead frame that are components of a lead frame assembly that is Embodiment 12.
[0041] FIG. 24 includes a plan view and a cross sectional view illustrating a step of Embodiment 12 in the state where a cover frame is mounted.
[0042] FIG. 25 includes a plan view and a cross sectional view illustrating a step of Embodiment 12 in the state where a sensor element is mounted at a lead frame assembly.
[0043] FIG. 26 illustrates a step of Embodiment 12, including a plan view after transfer molding and a cross sectional view illustrating the state where a lead frame is pressed with a mold during transfer molding.
[0044] FIG. 27 illustrates a method that is Embodiment 13 to form a communication hole at a lead frame by additional processing.
[0045] FIG. 28 illustrates a method that is Embodiment 14 to form a communication hole using a pipe-formed member.
[0046] FIG. 29 illustrates a die-bond material receiver at the periphery of a through hole that is Embodiment 15.
DESCRIPTION OF EMBODIMENTS
[0047] The following describes embodiments of the present invention in details, with reference to the drawings.
Embodiment 1
[0048] The following describes Embodiment 1 that is one embodiment of the present invention.
[0049] As illustrated in FIG. 1 , a thermal flow meter 100 is attached at its flange part 99 to an intake pipe 140 by mechanical fastening such as using a screw. The thermal flow meter 100 roughly includes a bypass-passage 101 , a circuit chamber 102 and a connector part 103 , and is electrically connected to an ECU that controls an engine via a connector lead 111 in the connector part 103 . Intake air 110 flowing through the intake pipe 140 enters the bypass-passage through an upstream-side opening 105 of the thermal flow meter 100 and goes out through a downstream-side opening 106 . A sensor element 701 is disposed in the bypass-passage 101 to detect the flow of air that is branched off into the bypass-passage 101 out of the intake air 110 passing through the intake pipe 140 .
[0050] Referring to FIG. 2 that is a cross section taken along A-A of FIG. 1 , the following describes components making up the thermal flow meter 100 and the structure.
[0051] The circuit chamber 102 and the bypass-passage 101 of the thermal flow meter 100 are surrounded with a housing member 201 , a cover member 202 , and a chip package 203 containing the sensor element 701 and its driving circuit. These members are mutually bonded at their periphery with thermosetting adhesive 104 . This can keep the interior of the circuit chamber 102 airtight perfectly, and intake air 110 passing through the sub-passage 101 does not enter the circuit chamber 102 . Such perfect airtightness of the circuit chamber, however, causes expansion of air in the circuit chamber during heating of the thermosetting adhesive 104 for curing, and so the housing member 201 and the cover member 202 may not be bonded correctly.
[0052] To avoid this, such expanded air has to be released from the circuit chamber 102 , and so a ventilation hole 108 is bored at the connector part 103 to communicate with the circuit chamber 102 for communication between the air inside the circuit chamber 102 and the atmosphere 109 outside the intake Pipe.
[0053] An outer lead 305 of the chip package 203 and the connector lead 111 inside the connector part 103 are electrically connected via aluminum wire 112 , for example. Herein as illustrated in FIG. 2( b ), the outer lead 305 of the chip package may double as the connector lead 111 , and in this case, the aluminum wire 112 and the circuit chamber 102 may be omitted.
[0054] FIG. 3( a ) illustrates the minimum circuit configuration of a flow detection part, FIG. 3( b ) illustrates the configuration of the flow detection part and FIG. 3( c ) is a cross-sectional view taken along A-A of FIG. 3( b ). Referring to these drawings, the following describes a typical example of the flow detection part that is formed by patterning on a detection part diaphragm 702 and its operation principle.
[0055] On the diaphragm 702 , a flow detection part 4 is formed by patterning. The flow detection part 4 includes a heater resistor (heating resistor) 7 and a non-thermal resistor (thermosensitive resistor) 9 , and they are connected to a driving circuit 5 that is provided separately from the flow detection part 4 . The heater resistor 7 generates heat when being energized by current fed from the driving circuit 5 described later, so as to heat the surrounding fluid (air) to be at a temperature higher than the surrounding temperature at least. The non-thermal resistor 9 detects a temperature of the fluid surrounding the flow detection part, and the heater resistor 7 is heat-controlled by the driving circuit 5 so that the temperature thereof is higher than the detected temperature by a predetermined temperature or more.
[0056] The flow detection part 4 further includes temperature sensors (temperature detection resistors) 11 , 12 disposed adjacent to the downstream of the heater resistor 7 and temperature sensors (temperature detection resistors) 13 , 14 disposed adjacent to the upstream of the heater resistor 7 , which are connected to a constant voltage source 26 that is separately provided from the flow detection part 4 and make up a bridge circuit 45 .
[0057] The driving circuit 5 includes fixed resistors 8 , 10 and an operational amplifier 15 disposed therein, and so is configured as a heater control circuit to heat-control the heater resistor 7 . This driving circuit 5 allows current from the operational amplifier 15 to be fed to the heater resistor 7 so as to heat-control the heater resistor 7 based on the detection temperature of the non-thermal resistor 9 until the heating temperature of the heater resistor 7 has a predetermined value relative to the surrounding temperature (fluid).
[0058] In this way, a change in temperature distribution (heat quantity) of the fluid between the temperature sensors 13 and 14 disposed adjacent to the upstream of the heater resistor 7 and the temperature sensors 11 and 12 disposed adjacent to the downstream of the heater resistor 7 can be detected as the flow of the fluid (detected flow Q). When the mass airflow changes, thermal influences from the heater resistors on the temperature sensors 13 and 14 disposed adjacent to the upstream and the temperature sensors 11 and 12 disposed adjacent to the downstream of the heater resistor 7 change, and such a change is detected, whereby a voltage signal corresponding to the mass airflow and its direction can be obtained.
[0059] As illustrated in FIG. 3( b ), the heater resistor 7 has a folded pattern of a resistor to be oblong, on both sides of which (upstream and downstream sides) the temperature sensors 11 and 12 and the temperature sensors 13 and 14 are disposed. The heater resistor 7 and the temperature sensors 11 , 12 , 13 and 14 are disposed on the diaphragm 702 that is formed by etching from the rear face of the sensor element 701 as a silicon substrate, for example, to have a small thermal capacity. The non-thermal resistor 9 may be disposed at a place less susceptible to temperature influences from heating of the heater resistor 7 , e.g., at a place outside of the diaphragm 702 . These elements are connected for electrical connection with a circuit part by gold wire bonding, for example, from an electrode extraction part 42 . In the present embodiment, the potential at the midpoint of the bridge including the temperature sensors 11 , 12 , 13 and 14 is input to a characteristic adjusting circuit 6 .
[0060] Referring next to FIG. 4( a ) that is a front view of a package illustrating the internal configuration with broken lines and FIG. 4( b ) that is a cross-sectional view of FIG. 4( a ), the following describes the shape of the chip package 203 .
[0061] The sensor element 701 typically has a rectangular shape. At the detection part of the sensor element 701 , the diaphragm 702 is disposed as described above, and this diaphragm 702 is disposed inside the sub-passage 101 illustrated in FIG. 1 , through which air as a measurement target flows.
[0062] The diaphragm 702 is formed by etching from the rear-face direction of the sensor element 701 as stated above, and a cavity 703 is formed at the rear face. The diaphragm 702 is made to be a thin film mainly because a thinner film can decrease the thermal capacity, leading to advantages of improving thermal responsivity as well as lowering power consumption.
[0063] The cavity 703 below the diaphragm 702 and the circuit chamber 102 communicate with each other via a communication hole 705 bored at a lead frame 704 . The lead frame 704 may be made of a material such as Cu or Fe—Ni having a thickness from about 0.1 mm to 1 mm. When the diaphragm 702 and the circuit chamber 102 communicate with each other, the communication hole 705 has to be bored at the lead frame 704 or a resin part 601 of the chip package 203 . Boring of a hole at the resin part 601 or at the lead frame 704 by additional process after packaging means an increase in the number of steps compared with the conventional packaging procedure, and such a step includes micromachining, and so requires high level of difficulty for machining.
[0064] Then, the present invention provides the communication hole 705 inside the lead frame 704 by the following procedure for communication between the circuit chamber 102 and the cavity 703 under the diaphragm. In the following, an assembly (including a lead frame 301 , a cover frame 401 and adhesive 404 in the present embodiment) of the minimum components of the lead frame 704 to configure the communication hole 705 is called a lead frame assembly 704 .
[0065] Referring to FIGS. 5 to 8 , the following describes the manufacturing procedure of the chip package 203 .
[0066] Firstly, the cover frame 401 and the lead frame 301 are prepared. Hereinafter, the aforementioned first lead frame and second lead frame are called the cover frame 401 and the lead frame 301 , respectively. Referring to FIGS. 5( a )( b ) and ( c ), the following describes the shapes of the cover frame 401 , the lead frame 301 and the adhesive 404 to bond the cover frame 401 and the lead frame 301 .
[0067] Firstly, the configuration of the lead frame 301 is described with reference to FIG. 5( c ). The lead frame 301 includes an outer frame 302 , a die pad 303 to mount an electronic component such as a sensor element and the cover frame 401 thereon, a tie bar 304 to joint the outer frame 302 to the die pad so as not to cause displacement of these components due to influences from resin flow that may occur during molding by transfer molding described later, and an outer lead 305 of the chip package.
[0068] Next, the configuration of the cover frame 401 is described with reference to FIG. 5( a ).
[0069] The cover frame 401 includes a groove 402 (hereinafter called a communication groove 402 ) to release air from the cavity 703 below the diaphragm, which is formed by half etching or pressing, and a through hole 403 passing through the groove part, which is bored at a part immediately below the diaphragm in the area where the sensor element is to be die-bonded. Such a cover frame 401 is overlaid to the lead frame 301 with the sheet adhesive 404 illustrated in FIG. 5( b ).
[0070] FIG. 6( a ) is a front view illustrating the state where the lead frame 301 and the cover frame 401 are bonded with the adhesive 404 , and FIG. 6( b ) is a cross sectional view thereof. Bonding of the lead frame 301 and the cover frame 401 via the adhesive 404 forms a closed space that communicates with the through hole 403 . Hereinafter this closed space defines the communication hole 705 .
[0071] FIG. 7( a ) is a front view illustrating the state where the sensor element 701 is structurally or electrically bonded to the lead frame assembly 704 , and FIG. 7( b ) is a cross sectional view thereof.
[0072] After applying a die-bond material 501 made of Ag paste or thermosetting adhesive so as to surround the through hole on the cover frame 401 , the sensor element 701 is die-bonded, and the die-bond material 501 and the adhesive 404 are heated in an oven for curing. Herein, the lead frame 301 and the cover frame 401 may be made of the same type of materials or different types of materials, between which one that is suitable for the overall shape of the chip package 203 may be selected. For instance, when the area of the lead frame 301 is sufficiently larger than that of the cover frame 401 , the cover frame 401 may be made of a material having a linear expansion coefficient closer to that of the sensor element 701 than that of the lead frame 301 , whereby stress applied to the sensor element 701 during heating for curing can be alleviated.
[0073] Then, the electrode extraction part 42 on the sensor element 701 and a bonding part 503 on the lead frame 301 are connected by wire bonding using Au wire 504 .
[0074] FIG. 8( a ) is a front view illustrating the state where molding is performed for the lead frame assembly 704 on which the sensor element 701 has been mounted, and FIG. 8( b ) is a cross sectional view illustrating the state where the lead frame assembly is set in a mold.
[0075] The lead frame assembly 704 on which the sensor element 701 has been mounted, which is prepared by the procedure till FIG. 7 as stated above, is set on a lower mold for transfer molding 1103 , which is then sandwiched with an upper mold for transfer molding 1102 . Thermosetting resin such as epoxy or polyamide that is heated to about 200° C. to 300° C. is injected into the space defined between the lower mold for transfer molding 1103 and the upper mold for transfer molding 1102 at an injection pressure of about 5 to 10 MPa, thus packaging the lead frame assembly 704 . Hereinafter the shape of such a lead frame assembly 704 , on which an electronic component such as the sensor element 701 has been mounted, just after packaging, is called a package assembly 602 .
[0076] At this time, if the injection pressure of the resin part 601 is too high, the Au wire 504 will be washed away by the resin part 601 and will fall, and the Au wire 504 may come into contact with the cover frame 401 . When the cover frame 401 is made of a metal material, short-circuit occurs at the Au wire 504 , and the sensor element 701 and the outer lead 305 may not be electrically connected correctly.
[0077] To avoid this, the cover frame 401 may be made of a material not a metal only but silicon or glass. In the case of silicon or glass used, the communication groove 402 and the through hole 403 may be formed by wet etching, dry etching or blasting. Such a configuration including silicon or glass may be applicable to all cover frames 401 in the below-described embodiments.
[0078] Cutting the tie bar 304 of the package assembly 602 , a part connecting the outer leads 305 of the tie bar 304 and the leading end of the outer lead 305 completes the chip package 203 of FIG. 4 as described above. At this time, the outer lead 305 particularly has to be cut at its cutting line 1101 . The outer lead may be cut at the cutting line 1101 so as to surely include the communication groove 402 , whereby the opening 708 of the communication hole can be obtained as in FIG. 4( b ) as described above.
[0079] As stated above, the chip package 203 , the housing member 201 and the cover member 202 define the sub-passage 101 and the circuit chamber 102 , and so air inside the cavity 703 below the diaphragm flows through the communication hole 705 , the circuit chamber 102 and the ventilation hole 108 to communicate with the atmosphere 109 outside of the intake pipe through the connector part 103 .
[0080] Packaging of the sensor element 701 by such manufacturing procedure and to have such a configuration allows the space below the diaphragm to be cut off from the interior of the intake pipe 140 , and so concern about water droplet and contaminations to reach there can be removed. Further, the cavity 703 below the diaphragm and the circuit chamber 102 can communicate with each other without adding any step to a typical packaging technique conventionally conducted. Since the cavity 703 below the diaphragm communicates with the atmosphere, deformation of the diaphragm 702 can be reduced, which is due to a pressure difference between the surface side and the rear face side of the diaphragm, and so a change in values of resistance of resistors making up the flow detection part 4 on the diaphragm 702 due to Piezoresistive effect can be reduced, and a change in characteristics of the thermal flow meter 100 can be reduced. Clogging of the opening leading to the space at the rear face of the diaphragm also can be prevented, and so a reliable product can be manufactured.
[0081] A ventilation hole that is provided at the sensor element for communication between the space at the rear face of the diaphragm and the exterior of the intake pipe will not be clogged, and the sensor element can be manufactured while suppressing variations in mounting.
[0082] Although the present embodiment illustrates the example providing a communication hole in the lead frame, including the below-described embodiments, the present invention is intended to provide a communication hole in a member to support the sensor element. That is, the present invention is not limited to these embodiments, and a communication hole may be provided at a substrate making up a circuit pattern, for example.
Embodiment 2
[0083] Referring to FIG. 9 , the following describes a cover frame 401 , a lead frame 301 and the shape to apply adhesive 404 that is another proposal for Embodiment 1.
[0084] Embodiment 1 requires half etching or pressing to form the communication groove 402 at the cover frame 401 . The present embodiment is a method to simply the manufacturing process of a chip package by eliminating such a step. As illustrated in FIG. 9( b ), paste-like adhesive 404 is applied by dispensing so as to surround the range including a through hole 403 and an outer lead 305 , or sheet-like adhesive is cut and attached, whereby a communication hole 705 can be formed. This can manufacture the chip package 203 with a smaller number of steps than that of Embodiment 1.
Embodiment 3
[0085] Referring to FIGS. 10( a )( b ) and ( c ), the following describes a still another proposal for a cover frame 401 , a lead frame 301 and the shape to apply adhesive 404 to mount a sensor element 701 on a lead frame assembly 704 more precisely than Embodiment 1.
[0086] The communication groove 402 disposed at the cover frame 401 makes the wall thickness of the cover frame 401 nonuniform, and so there is a concern to degrade flatness of the plane on which a sensor element 701 is to be mounted. The communication groove 402 disposed at the lead frame 301 then leads to a concern to degrade the flatness similarly to the case of the cover frame. The communication groove 402 may be disposed at the lead frame 301 , and degradation in flatness of the lead frame 301 may be accommodated with the adhesive 404 .
[0087] From the viewpoint of the accuracy in height to mount the sensor element 701 , the adhesive 404 may be applied using sheet adhesive instead of applying on the lead frame by dispensing to suppress variations in dimensions in the lamination direction. However, it is difficult to cut it into the shape surrounding the cavity as in the application area of the adhesive 404 illustrated in FIG. 9( b ), and so adhesive 404 that is made of a porous material that transmits not resin but air is preferably used. The present embodiment enables the lead frame assembly 704 , on which the sensor element 701 can be mounted more precisely.
Embodiment 4
[0088] Referring to FIG. 8 , the following describes the transfer molding processing of Embodiment 1 again. The outer lead 305 and the tie bar 304 protrude from the resin part 601 of the chip package 203 to the outside, and so the upper mold for transfer molding 1102 and the lower mold for transfer molding 1103 are manufactured to avoid the outer lead 305 and the tie bar 304 .
[0089] As a result, if the cover frame 401 is displaced on the lead frame 301 from a predetermined shape during mounting, there occurs a gap between the outer lead 305 , which is formed by overlapping of the lead frame 301 and the cover frame 401 , and the mold, and then the resin part 601 flows out from this gap. This results in incorrect shape of the chip package 203 . In order to prevent the leakage of resin during transfer molding, the dimension of the gap has to be about 5/1,000 mm, and so very high accuracy is required to mount the cover frame 401 on the lead frame 301 .
[0090] Referring to FIG. 11 , the following describes the structure and the manufacturing method to relax restrictions on such an allowable gap dimension. The basic components, structure and manufacturing steps are the same as those of Embodiments 1 to 3.
[0091] When the lead frame 301 and the cover frame 401 are bonded with the adhesive 404 , the communication groove 402 , which is formed in any Embodiments 1 to 3, is formed so as to define a closed space inside the cover frame 401 . Next, when the lead frame assembly 704 is molded, the package assembly 602 is formed so as to make sure that the molding range of the resin part 601 is within the range including the entire cover frame 401 , and then when the package assembly 602 is cut out from the outer frame 302 , cutting is performed at the cutting line 1101 of FIG. 11 in the cover frame 401 . Herein, the cutting line 1101 is set so as to pass through a part of the closed space of the adhesion groove. This forms the opening 708 of the communication hole.
[0092] This structure prevents the leakage of resin to the outside as long as the upper mold for transfer molding 1102 and the lower mold for transfer molding 1103 cover the range including the communication groove 402 while having the width of about ±0.2 mm at the periphery of the part of the cover frame 401 making up the outer lead 305 , even when there is a displacement of about ±0.1 mm, for example, of the cover frame 401 relative to the lead frame 301 during adhesion, and so the chip package 203 formed can have a correct shape.
Embodiment 5
[0093] FIG. 12 illustrates the opening 708 of the communication hole that is obtained after cutting of the outer lead 305 .
[0094] In Embodiment 1 or Embodiment 3, when the outer lead 305 is cut after preparing the package assembly 602 , a punch for cutting may crush the upper side face 1201 of the communication hole when pushing the outer lead 305 for cutting, which may block the communication hole 705 .
[0095] Let that t denotes the wall thickness of the lead frame and w denotes the width of the communication hole, a part of the communication hole passing through the cutting line 1101 desirably has a relationship of the width of communication hole w≦the wall thickness t.
Embodiment 6
[0096] FIG. 13( a ) illustrates an alternative proposal for Embodiment 5 including the package assembly 602 without the outer frame 302 , and FIG. 13( b ) illustrates the state of the opening 708 of the communication hole after cutting the outer lead 305 at the cutting line 1101 .
[0097] As illustrated in FIG. 13( b ), a plurality of communication grooves 402 provided can increase the total area of the opening 708 of the communication hole, whereby reliability of the connection between the cavity 703 at the rear face of the diaphragm and the opening 708 of the communication hole via the communication hole 705 can be improved.
Embodiment 7
[0098] In Embodiments 1 to 6, the chip component to be mounted on the cover frame 401 is not limited to the sensor element 701 only. The present embodiment illustrates the example where a plurality of chip components including a sensor element is mounted on the cover frame 401 . Referring again to FIG. 13( a ), the following describes the form to mount a plurality of chips.
[0099] When a chip 1301 including an arithmetic circuit, for example, in addition to the sensor element 701 , is mounted on a first lead frame, the minimum area of the first lead frame will be increased by the area of the chip 1301 at least.
[0100] The present embodiment can be manufactured by the same manufacturing procedure and with the structure of the components and the components used as those of Embodiment 1. However, in the case of a broader communication groove 402 , the cover frame 401 may be deformed due to the injection pressure of thermosetting resin, so that the state of the sensor element 701 and the chip 1301 mounted becomes instable and variations in dimensions to mount chip components in the lamination direction may increase.
[0101] Then, a part 1302 free from the communication hole 705 is desirably disposed at an area immediately below the sensor element 701 or the chip 1301 , such an area being disposed partially or entirely on the rear face side of the chip 1301 .
Embodiment 8
[0102] Referring again to FIG. 2 that is a cross sectional view of the thermal flow meter, the following describes a method to improve the accuracy in position to mount the sensor element 701 to reduce variations in characteristics of the thermal flow meter 100 .
[0103] The positional accuracy of the sensor element 701 in the sub-passage 101 of the thermal flow meter 100 affects the variations in characteristics of the thermal flow meter 100 . The chip package 203 is bonded to the housing member 201 and the cover member 202 that make up the sub-passage 101 . This means that, in order to mount the sensor element 701 in the sub-passage 101 precisely, variations in dimensions between the surface of the resin part 601 and the surface of the sensor element 701 that is at the bonding face with the housing member 201 and the cover member 202 have to be minimized.
[0104] Referring next to FIG. 8( b ), the following considers the integration of variations in dimensions inside the chip package 203 . The positional relationship between the sensor element 701 and the resin part 601 depends on the transfer molding step. At this time, since the lead frame 301 is set to be sandwiched between the upper mold for transfer molding 1102 and the lower mold for transfer molding, the lead frame surface will serve as a reference for the dimensional tolerance.
[0105] This means that factors of variations in dimensions between the surface of the resin part 601 and the sensor element 701 in the lamination direction during mounting include the flatness of the face to mount the lead frame 301 thereon, variations in thickness of the adhesive 404 , variations in thickness of the cover frame 401 , flatness of the bonding face between the cover frame 401 and the lead frame 301 , flatness of the face of the cover frame 401 to mount the sensor element 701 thereon, and variations in thickness of the die-bond material 501 .
[0106] In the present embodiment, the cover frame 401 is bonded to the opposite side of Embodiment 1 to alleviate the factors of variations in the lamination direction of the sensor element 701 during mounting, and the die-bond material 501 is directly applied to the lead frame 301 , followed by mounting of the sensor element 701 . This can reduce the factors of variations in the lamination direction of the sensor element 701 during mounting to the flatness of the face to mount the lead frame 301 thereon and the variations in thickness of the die-bond material 501 only. The following describes the manufacturing procedure, the components included and the structure of the components with reference to FIGS. 14 to 19 .
[0107] Firstly, similarly to Embodiment 1, the lead frame 301 and the cover frame 401 are prepared (in the present embodiment, the aforementioned first lead frame and second lead frame are called a lead frame and a cover frame, respectively). FIG. 14( a ) describes the structure of the lead frame, FIG. 14( b ) describes the shape of the lead frame and the adhesive 404 to bond the cover frame 401 and the lead frame 301 , and FIG. 14( c ) describes the structure of the cover frame 401 .
[0108] The lead frame 301 includes a through hole 403 that is disposed immediately below a cavity 703 under the diaphragm of the sensor element 701 , a communication groove 402 to release air from the cavity 703 below the diaphragm, which is formed by etching or pressing, an outer frame 302 , a die pad 303 to mount an electronic component such as a sensor element 701 thereon, a tie bar 304 to joint the outer frame to the die pad 303 so as not to cause displacement of these components due to influences from resin flow during transfer molding, and an outer lead 305 to serve as a terminal of the chip package 203 . This structure is preferable because it enables a simple configuration just by cutting the outer peripheral shape surrounding the communication groove 402 to process a cover frame 401 .
[0109] FIG. 15 illustrates the state where the lead frame 301 and the cover frame 401 are bonded with the adhesive 404 .
[0110] The adhesive 404 is applied at an area between the lead frame 301 and the cover frame 401 and surrounding an adhesion groove 405 . At this time, since there is no need to provide an internal range of the application of the adhesive 404 where the adhesive 404 is not to be applied, sheet-form adhesive 404 is used preferably, whereby the step can be very simple.
[0111] FIG. 16 illustrates the state where the sensor element 701 is structurally or electrically bonded to the lead frame assembly 704 , where FIG. 16( a ) is a front view and FIG. 16( b ) is a cross sectional view.
[0112] A die-bond material 501 that is Ag paste or epoxy-based material is applied on the lead frame 301 so as to surround the through hole, and then sensor element 701 is die-bonded, followed by heating of the die-bond material 501 and the adhesive 404 for curing.
[0113] Subsequently, an electrode extraction part 42 on the sensor element 701 and a bonding part 503 on the lead frame 301 are connected by wire bonding using Au wire 504 .
[0114] The subsequent steps to prepare the chip package 203 are the same as those in Embodiment 1.
[0115] Packaging of the sensor element 701 with such structure, components included, manufacturing procedure similarly to Embodiment 1 allows the cavity 703 below the diaphragm to be cut off from the interior of the intake pipe 140 , and so concern about water droplet and contamination to reach there can be removed. Further, the space below the diaphragm and the atmosphere can communicate with each other, whereby a concern about the deformation of the diaphragm 702 can be removed, which is due to a pressure difference between the surface side and the rear face side of the diaphragm, and so a change in values of resistance due to Piezoresistive effect, i.e., a change in characteristics can be reduced.
[0116] Further, the sensor element 701 can be packaged precisely, which can contribute to suppress variations in characteristics of the thermal flow meter 100 .
[0117] Embodiments 5, 6 and 7 may be combined, whereby needless to say, a chip package can be manufactured more precisely.
Embodiment 9
[0118] Referring to FIGS. 17( a ) ( b ) and ( c ), the following describes a cover frame 401 , a lead frame 301 and the shape to apply adhesive 404 in Embodiment 9. Embodiment 8 requires etching or pressing at the cover frame 401 to form the components making up the lead frame assembly 704 . The present embodiment can eliminate such a step, whereby the manufacturing process of a chip package 203 can be simplified.
[0119] As illustrated in FIG. 17( b ), adhesive 404 is applied so as to surround the range including a through hole 403 and an outer lead 305 , whereby a communication hole 705 can be formed. This can manufacture the chip package 203 with a smaller number of steps than that of Embodiment 8.
Embodiment 10
[0120] Referring to FIGS. 18( a )( b ) and ( c ), the following describes a cover frame 401 , a lead frame 301 and the shape to apply adhesive 404 in Embodiment 10.
[0121] The communication groove 402 disposed at the lead frame 301 in the above Embodiment 8 makes the wall thickness of the lead frame 301 nonuniform as illustrated in FIG. 16 , and so there is a concern to degrade flatness of the plane on which a sensor element 701 is to be mounted.
[0122] Then, as illustrated in FIG. 18 , the communication groove 402 of the present embodiment is disposed at the cover frame 401 to accommodate the degradation in flatness of the cover frame 401 with the adhesive 404 .
[0123] Further, from the viewpoint of the accuracy in height to mount the sensor element 701 , the adhesive 404 may be applied using sheet adhesive instead of applying on the lead frame by dispensing to suppress variations in dimensions in the height direction. However, it is difficult to cut it into the shape surrounding the cavity as in FIG. 14( b ) using the sheet adhesive, a shape without a hole as in FIG. 18( b ) is preferable.
[0124] Then the adhesive 404 that is made of a porous material that transmits not resin but air is preferably used.
Embodiment 11
[0125] Embodiments 1 to 10 describe the lead frame assembly 704 including the lead frame 301 , the adhesive 404 , the cover frame 401 , the sensor element 701 , the die-bond material 501 and the Au wire 504 as a minimum configuration, and the following describes the present embodiment as an alternative proposal that does not include the cover frame 401 to reduce the number of components. The basic steps are the same as those in Embodiment 1 and Embodiment 8.
[0126] FIGS. 19 to 22 illustrate the structure of a lead frame 301 in the present embodiment. In these drawings, (a) is a front view of the lead frame 301 and (b) is a cross-sectional view including the center of the through hole 403 .
[0127] Firstly the lead frame 301 illustrated in FIG. 19 is prepared. Similarly to the aforementioned lead frame 301 , the lead frame 301 includes the die pad 303 , the tie bar 304 , a dam bar 306 , the outer lead 305 and the outer frame 302 . Then, the entire lead frame 301 is divided into a main frame 2024 and a tab lead 2023 at a mountain folding line 2201 as the border, where the die pad 303 , the tie bar 304 , the through hole 403 in the range including at least a part of the cavity under the diaphragm when the sensor element 701 is mounted on the die pad 303 , and the tab lead 2023 are disposed on the main frame 2024 side. On the tab lead 2023 side, the communication groove 402 is formed as a recess by pressing performed from the face on the opposite side of the sensor-element mounting face toward the sensor-element mounting plane, and the through hole 403 and the communication groove 402 are disposed to be overlapped each other when the lead frame is folded by 180 degrees along the mountain folding line 2201 . Adhesive is then applied to the main frame 2024 side or the tab lead 2023 side so as to surround the communication groove 402 entirely, followed by bending of the lead frame along the mountain folding line 2201 , whereby the tab lead 2023 and the main frame 2024 are bonded with the adhesive 404 . The subsequent steps following the mounting of the sensor element 701 are the same as those in Embodiment 8, where the mountain folding line 2201 is used as a valley folding line, and a communication groove 402 is disposed at the main frame 2024 and a through hole 403 is bored at the tab lead 2023 similarly to Embodiment 8.
[0128] Considering the cover frame 401 in Embodiments 2 to 7 and Embodiment 9 to 10 as the tab lead 2023 for replacement, the members making up the communication groove 402 and the through hole 403 and the range to apply the adhesive 404 may have the same configuration, whereby the same advantageous effects from these embodiments can be achieved for the problems to be solved by the embodiments.
[0129] FIGS. 21 and 22 illustrate an example where the communication groove 402 of the present embodiment is formed by half etching, from which the same advantageous effects can be obtained similarly.
Embodiment 12
[0130] In Embodiments 1 to 11, when cutting out the chip package 203 and the outer lead 305 from the outer frame 302 of the package assembly 602 , the outer lead 305 making up the communication hole 705 is disconnected, whereby the opening 708 of the communication hole is formed. However, when disconnecting the outer lead 305 to make up the communication hole 705 , there is a concern to crush the communication hole 705 with a punch for disconnection, thus blocking the opening 708 of the communication hole. To avoid this concern, the present embodiment proposes another method to form the opening 708 of the communication hole by way of a typical example of the manufacturing procedure and the structure illustrated in FIG. 1 , with reference to FIGS. 23 to 26 .
[0131] Firstly a lead frame 301 and a cover frame 401 are prepared. The lead frame 301 has the same configuration as that of the lead frame in the aforementioned Embodiment 1.
[0132] Referring to FIG. 23( a ), the configuration of the cover frame 401 is described below. To release air from the cavity 703 below the diaphragm, the cover frame 401 includes a through hole 403 disposed immediately below the diaphragm, a communication groove 402 that is formed by half etching or pressing, and at least one or a plurality of lead frame openings 2301 to connect the communication groove 402 and the sensor-element mounting face.
[0133] FIG. 24( a ) is a front view illustrating the state where the lead frame 301 and the cover frame 401 are bonded with adhesive 404 , and FIG. 24( b ) is a cross-sectional view thereof. When the lead frame 301 and the cover frame 401 are bonded with the adhesive 404 , the communication groove 402 leading to the through hole 403 is formed.
[0134] FIG. 25( a ) is a front view illustrating the state where the sensor element 701 is structurally or electrically bonded to the lead frame assembly 704 , and FIG. 25( b ) is a cross sectional view thereof.
[0135] After applying a die-bond material 501 made of Ag paste or thermosetting adhesive so as to surround the through hole on the cover frame 401 , the sensor element 701 is die-bonded, and the die-bond material and the adhesive are heated in an oven for curing.
[0136] Then, an electrode extraction part 42 on the sensor element 701 and a bonding part 503 on the lead frame are connected by wire bonding using Au wire 504 .
[0137] FIG. 26 illustrates the state where molding is performed for the lead frame assembly 704 on which the sensor element 701 has been mounted.
[0138] The lead frame assembly 704 on which the sensor element 701 has been mounted, which is prepared by the procedure till FIG. 26 as stated above, is set in a mold for transfer molding, and resin such as epoxy or polyamide is poured into the mold by transfer molding, thus forming a package assembly 602 . At this time, an opening 2301 of the lead frame is covered with a pin 2602 that is larger than the opening 2301 . This can prevent the transfer molding resin from flowing into the communication hole 705 , and the place covered with the pin 2602 becomes a package opening 2601 after releasing of the mold for transfer molding, and the combination of the opening 2301 of the lead frame and the package opening 2601 forms an opening 708 of the communication hole of the package assembly 602 . The subsequent manufacturing procedure to prepare the chip package 203 is the same as those in Embodiment 1.
[0139] Such manufacturing procedure and configuration can form the opening 708 of the communication hole without cutting the outer lead 305 making up the communication hole 705 , thereby removing a concern to block the communication hole during disconnection of the outer lead 305 .
[0140] The present embodiment can be applied to Embodiments 2 and 3 as well as Embodiments 7 to 11, from each of which the same advantageous effects can be obtained.
Embodiment 13
[0141] Referring to FIG. 27 , Embodiment 13 is described below. The present embodiment includes additional processing performed to the lead frame 301 so as to form a communication hole 705 and a through hole 403 . When the wall thickness of a material for the lead frame is sufficiently thick of 2 mm or more, for example, a hole can be bored there in the thickness direction using a drill of about φ 1 mm.
[0142] A horizontal hole vertical to the face on which the sensor element 701 is to be mounted is bored at a die pad to be a through hole 403 . Another horizontal hole is bored from the outside of the outer frame 302 so as to intersect the through hole 403 and penetrate through the outer lead 305 in the direction parallel to the sensor-element 701 mounting face to be a communication hole 705 . The thus prepared lead frame 301 is a lead frame 704 , and a chip package 203 is manufactured by the same steps as those in Embodiment 1.
[0143] The present embodiment can reduce the number of components as compared with Embodiments 1, 8 and 11, and the lead frame assembly can be formed of materials having minimum sizes. As compared with the case of bonding lead frames or separate members to form a communication hole as in Embodiments 1 to 11, there is no concern to block the communication hole 705 during transfer molding or during cutting of the outer lead, and so reliability of the connection between the cavity 703 below the diaphragm and the opening 708 of the communication hole can be improved.
Embodiment 14
[0144] FIG. 28 illustrates another proposal to improve the reliability of connection between the cavity 703 below the diaphragm and the opening 708 of the communication hole, referring to FIG. 27 . Embodiment 8 illustrates the configuration of disposing the cover frame 401 at the rear face of the communication hole of the lead frame 301 . The present embodiment includes, instead of the cover frame 401 , a pipe-formed member 2701 under the through hole that is bonded with adhesion or by welding. The pipe-formed member may be made of soft metal such as copper or a resin material having a melting point from about 100° C. to 200° C. or higher that is a temperature during injection for transfer molding, for example. After bonding to the lead frame 301 , the pipe-formed member 2701 is bent toward the direction where the circuit chamber of the thermal flow meter 100 is disposed, which then becomes a lead frame assembly 704 . The subsequent steps to manufacture the thermal flow meter are the same as those in Embodiment 8.
[0145] This can avoid a concern about the adhesive 404 protruding over the communication hole 705 , which is due to the communication hole 705 made up of two members, and so the cavity 703 below the diaphragm and the opening 708 of the communication hole can be connected more reliably.
Embodiment 15
[0146] FIG. 29 is an enlarged cross-sectional view of a plane that passes through the center line of the through hole 403 . In the case of Embodiments 1 to 13, if the amount of the die-bond material 501 applied is not appropriate when the sensor element 701 is die-bonded on the lead frame 301 , the cover frame 401 or the tab lead 2023 , the die-bond material 501 will flow out to the through hole 403 as in FIG. 29( a ) and may block the through hole 403 . To prevent this, a die-bond material receiver 2801 is disposed so as to surround the through hole 403 as in FIG. 29( b ). The die-bond material receiver 2801 is a recess that is lower than the applied face of the die-bond material 501 (dam structure), and so variations in the amount of the die-bond material 501 applied can be accommodated with the volume of the recess.
[0147] The present embodiment alleviates a concern about the die-bond material 501 to stick out over the through hole 403 , and so the cavity 703 below the diaphragm and the opening 708 of the communication hole 705 can be connected more reliably.
REFERENCE SIGNS LIST
[0000]
4 , 360 Flow detection part
5 Driving circuit
6 Characteristic adjusting circuit
7 Heater resistor
8 , 10 Fixed resistor
9 Non-thermal resistor
11 to 14 Temperature sensor (temperature detection resistor)
15 Operational amplifier
26 Constant voltage source
42 Electrode extraction part
99 Flange part
100 Thermal flow meter
101 Sub-passage
102 Circuit chamber
103 Connector part
104 Thermosetting adhesive
105 Upstream side opening
106 Downstream side opening
107 , 701 Sensor element
108 Ventilation hole
109 Atmosphere outside intake pipe
110 Intake air
111 Connector lead
112 Aluminum wire
140 Intake pipe
201 Housing member
202 Cover member
203 Chip package
301 Lead frame
302 Outer frame
303 Die pad
304 Tie bar
305 Outer lead
306 Dam bar
331 Heater
332 Upstream side thermosensitive resistor
333 Downstream side thermosensitive resistor
401 Cover frame
402 Communication groove
403 Through hole
404 Adhesive
501 Die-bond material
503 Bonding part
504 Au wire
601 Resin part
602 Package assembly
702 Diaphragm
703 Cavity
704 Lead frame (lead frame assembly)
705 Communication hole
708 Opening of communication hole
1101 Cutting line of outer lead making up communication hole
1102 Upper mold for transfer molding
1103 Lower mold for transfer molding
1201 Upper side face of communication groove
1301 Chip
1302 Part without communication hole 705
2023 Tab lead
2024 Main frame
2201 Mountain folding line
2202 Position to mount sensor element
2301 Lead frame opening
2601 Package opening
2602 Pin
2701 Pipe-formed member
2801 Die-bond material receiver | Airflow measuring apparatus compring: sub-passage that takes in part of flow of fluid flowing through an intake pipe; sensor element that is disposed in the sub-passage to measure the flow of fluid; a circuit part that converts the flow of fluid detected by the sensor element into an electric signal; connector part connected to the circuit part to output a signal externally; and casing that supports the sensor element and the circuit part, the sensor element being disposed in the intake pipe. The sensor element includes a cavity disposed at a semiconductor substrate, a diaphragm including a thin film part that covers the cavity. The sensor element on a lead frame have surfaces that are mold-packaged with resin so that a diaphragm of the sensor element and part of the lead frame are exposed. One hole is disposed at the lead frame for communication between the cavity and exterior. | 5 |
TECHNICAL FIELD
The present disclosure relates to the field of a signal detection technology, in particular to a method and device for detecting a signal in a Long Term Evolution (LTE) system.
BACKGROUND
A LTE system is evolved from the third generation (3G) mobile communication system, improves and enhances the air access technology of the 3G system, and uses Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) as a unique standard of the evolution of its wireless network. A downlink peak rate of 100 Mbit/s and an uplink peak rate of 50 Mbit/s can be provided under a spectral bandwidth of 20 MHz to improve the performance of a cell-edge user, increase cell capacity and reduce system delay.
In an existing LTE system, a User Equipment (UE), when in a scheduling request period, can initiate a scheduling request to an evolved Node B (eNodeB) in an uplink subframe through a Physical Uplink Control Channel (PUCCH), which is in a format of 1, according to the requirement of a user, such as requirement of expanding resource; if there is no requirement of the user, the UE will not send information to the eNodeB even in a scheduling request period. Here, the PUCCH is divided into various formats, such as 1, 1a and 1b, according to different transmitted contents. Therefore, in the related technologies, the eNodeB needs to detect whether the UE sends a scheduling request to perform processing of the subsequent message.
In the operation process of the LTE system, the UE needs to perform feedback to a Physical Downlink Control Channel (PDCCH) and a Physical Downlink Shared Channel (PDSCH) in an eNodeB downlink subframe in a feedback period; if the UE detects a PDCCH and the Cyclic Redundancy Check (CRC) of the PDSCH is correct, the confirmation information fed back by the UE in the uplink subframe is Acknowledge (ACK) information; and if the UE detects a PDCCH and the CRC of the PDSCH is wrong, the confirmation information fed back by the UE in the uplink subframe is Non-Acknowledge (NACK) information. Here, if the UE feeds back ACK information of 1 bit or NACK information of 1 bit, the PUCCH in a format of 1a is adopted; if the UE feeds back ACK information of 2 bits or NACK information of 2 bits, the PUCCH in a format of 1b is adopted. If the UE fails to detect a PDCCH, it will not feed back the ACK or NACK information, i.e., the discontinuous transmission (DTX) occurs, which means that there is packet loss in the data transmitted from the eNodeB. If the UE feeds back the ACK or NACK information, the continuous transmission (CTX) occurs. Therefore, in the related technologies, the eNodeB needs to detect whether DTX occurs to the UE to perform processing of the subsequent message.
At present, it is impossible to detect whether the UE has sent a scheduling request or whether DTX occurs to the UE in the related technologies.
SUMMARY
Therefore, the main objective of the present disclosure is to provide a method and device for detecting a signal in an LTE system, so as to precisely, and simply and easily detect whether the UE initiates a scheduling request or whether DTX occurs to the UE.
In order to achieve the above objective, the technical solution of the present disclosure is implemented as follows.
The present disclosure provides a method for detecting a signal in an LTE system, including:
receiving, by an eNodeB, a data part of a signal sent by a UE on a channel resource;
calculating, by the eNodeB, a signal power P s and noise power P n according to the received data part of the signal sent by the UE on the channel resource, a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence, an orthogonal sequence W distributed to the UE, and a sequence W n orthogonal to the W and stored by the eNodeB; and
comparing a ratio of P s to P n with a predetermined threshold, and determining a corresponding detection result according to a comparison result.
Wherein the step of calculating P s may be specifically as follows:
performing a multiplication between the data part of the signal sent by the UE on the channel resource and a conjugate of the CAZAC sequence, and performing a summation of the multiplication to get a summation result; then performing a multiplication between the summation result and a conjugate of the orthogonal sequence W distributed to the UE, and performing a summation of the multiplication performed between the summation result and a conjugate of the orthogonal sequence W to get a second summation result; and squaring a modulus of the second summation result to obtain P.
Wherein the step of calculating P n may be specifically as follows:
performing a multiplication between the data part of the signal sent by the UE on the channel resource and a conjugate of the CAZAC sequence and performing a summation of the multiplication to get a summation result, then performing a multiplication between the summation result and a conjugate of the sequence W n and performing a summation of the multiplication performed between the summation result and a conjugate of the sequence W n to get a second summation result; and squaring a modulus of the second summation result to obtain P n .
In the solution, when the UE is in a scheduling request period, the step of determining the corresponding detection result according to the comparison result may be:
when the ratio of P s to P n is more than or equal to the predetermined threshold, it is determined that the UE sends a scheduling request; and when the ratio of P s to P n is less than the predetermined threshold, it is determined that the UE does not send the scheduling request.
In the solution, when the UE is in a feedback period, the step of determining the corresponding detection result according to the comparison result may be:
when the ratio of P s to P n is more than or equal to the predetermined threshold, it is determined that CTX occurs to the UE; and, when the ratio of P s to P n is less than the predetermined threshold, it is determined that DTX occurs to the UE.
In this solution, the sequence W n may be: W 3 =[+1 +1 −1 −1].
The present disclosure further provides a device for detecting a signal in an LTE system, including: a receiving module, a power calculating module, a ratio calculating module and a comparing module, wherein
the receiving module is arranged to receive a data part of a signal sent by a UE on a channel resource and send the data part to the power calculating module;
the power calculating module is arranged to calculate P s and P n according to the data part sent by the receiving module, a CAZAC sequence distributed to the UE, an orthogonal sequence W distributed to the UE, and a sequence W n orthogonal to the W and stored by the eNodeB, and send a calculation result to the ratio calculating module;
the ratio calculating module is arranged to calculate a ratio of the P s to the P n sent by the power calculating module, and send the calculated ratio to the comparing module; and
the comparing module is arranged to compare the ratio sent by the ratio calculating module with a predetermined threshold, and determine a corresponding detection result according to a comparison result.
Wherein the power calculating module may further include a multiplication and summation module and a modulus squaring module, wherein
the multiplication and summation module is arranged to perform a multiplication between the data part of the signal from the receiving module to which the UE sends the signal on the channel resource and a conjugate of the CAZAC sequence stored by the eNodeB and performing a summation of the multiplication to get a summation result, then performing a multiplication between the summation result and a conjugate of the orthogonal sequence W distributed to the UE and stored by the eNodeB and perform a summation of the multiplication performed between the summation result and a conjugate of the orthogonal sequence W to get a final calculation result, and send the final calculation result to the modulus squaring module; or
the multiplication and summation module is arranged to perform a multiplication between the data part of the signal from the receiving module to which the UE sends the signal on the channel resource and a conjugate of the CAZAC sequence stored by the eNodeB and performing a summation of the multiplication to get a summation result, then performing a multiplication between the summation result and a conjugate of the sequence W n stored by the eNodeB and performing a summation of the multiplication performed between the summation result and a conjugate of the sequence W n to get a final calculation result, and send the final calculation result to the modulus squaring module; and
the modulus squaring module is arranged to square a modulus of the result sent by the multiplication and summation module, and send a calculation result to the ratio calculating module;
correspondingly, the ratio calculating module is further arranged to calculate the ratio of P s to P n sent by the modulus squaring module and send the calculated ratio to the comparing module.
Wherein the power calculating module may calculate P s in the following way specifically: performing a multiplication between the data part of the signal sent by the UE on the channel resource and a conjugate of the CAZAC sequence and performing a summation of the multiplication to get a summation result, then performing a multiplication between the summation result and a conjugate of the orthogonal sequence W distributed to the UE and performing a summation of the multiplication performed between the summation result and a conjugate of the orthogonal sequence W to get a second summation result, and squaring a modulus of the second summation result to obtain P s .
Wherein the power calculating module may calculate the P n in the following way specifically: performing a multiplication between the data part of the signal sent by the UE on the channel resource and a conjugate of the CAZAC sequence and performing a summation of the multiplication to get a summation result, then performing a multiplication between the summation result and a conjugate of the sequence W n and performing a summation of the multiplication performed between the summation result and a conjugate of the sequence W n to get a second summation result, and squaring a modulus of the second summation result to obtain P n .
In the method and device for detecting a signal in an LTE system in the present disclosure, the eNodeB calculates the signal power P s and the noise power P n according to the data part of the signal sent by the UE on the channel resource, a CAZAC sequence and an orthogonal sequence W distributed to a UE, and a sequence W n orthogonal to the W and stored by itself, calculates the ratio of P s to P n , compares the ratio with the predetermined threshold, and determines a corresponding detection result according to a comparison result. Through the present disclosure, the eNodeB can detect whether the UE initiates the scheduling request or whether DTX occurs to the UE, so that the eNodeB can determine whether to continuously send a subsequent message or whether to resend the message which the UE has failed to receive.
In the solution, due to the introduction of the sequence W n , it is unnecessary to search unused channel resources during the calculation of the noise power P n , thereby reducing the detection complexity; meanwhile, because the noise power is calculated through the sequence W n , the precision of calculating the noise power is improved, thereby improving the accuracy of threshold decision and finally improving the scheduling performance of the eNodeB.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a diagram illustrating a implementation flow of a method for is detecting a signal in an LTE system in the present disclosure; and
FIG. 2 shows a diagram illustrating a structure of a device for detecting a signal in an LTE system in the present disclosure.
DETAILED DESCRIPTION
The basic idea of the present disclosure is to calculate a signal power P s and a noise power P n according to a sequence W n , the data part of a signal sent by a UE on a channel resource, and the CAZAC sequence distributed to the UE and an orthogonal sequence W distributed to the UE, calculate the ratio of the P s to the P n , compare the ratio with the predetermined threshold and determine a corresponding detection result according to the comparison result.
In the present disclosure, preferably, the sequence W n is W 3 =[+1 +1 −1 −1] and distributed by an eNodeB; the orthogonal sequence W distributed to the UE is: W 0 =[+1 +1 +1 +1], W 1 =[+1 −1 +1 −1] and W 2 =[+1 −1 −1 +1]; and for different users, the orthogonal sequence distributed to the UE can be any one of W 0 , W 1 or W 2 , wherein 0, 1, 2 are indexes of the orthogonal sequences, and the CAZAC sequence, W 0 , W 1 , W 2 and W 3 are all distributed by the eNodeB.
In practical application, the UE generates data from the CAZAC sequence, orthogonal sequence W 0 , W 1 or W 2 and other related parameters distributed by an eNodeB, and then sends the generated data, as the data part of the signal sent by itself, to the eNodeB on a distributed channel resource; and the eNodeB calculates the P s and P n according to the received data part, the sequence W n stored by itself, and the CAZAC sequence distributed to the UE and the orthogonal sequence distributed to the UE, wherein the CAZAC sequence and orthogonal sequence W 0 , W 1 or W 2 are stored in both the eNodeB and UE.
The present disclosure is further described below with reference to drawings and specific embodiments in details.
FIG. 1 shows a diagram illustrating the implementation flow of a method for detecting a signal in an LTE system in the present disclosure, as shown in FIG. 1 , the flow includes the following steps.
Step 101 : an eNodeB receives the data part of a signal sent by a UE on a channel resource;
wherein the data part of the signal sent by the UE on the channel resource is the data generated from parameters distributed by the eNodeB, by the UE on the distributed channel resource;
wherein the parameters which are distributed by the eNodeB are: CAZAC sequence, and orthogonal sequence W 0 , W 1 or W 2 .
Step 102 : the eNodeB performs a multiplication between the data part of the signal sent by the UE on the channel resource and the conjugate of the CAZAC sequence and performs a summation of the multiplication, wherein
this step can be represented by the formula (1):
Y′=ΣYC* (1)
wherein the Y is the data part of the signal sent by the UE on the channel resource, the C is the CAZAC sequence and the Y′ is the result obtained by performing a multiplication between Y and the conjugate of the C, and performing a summation of the multiplication performed between Y and the conjugate of the C.
Step 103 : a multiplication is performed between the Y′ and the conjugate of the orthogonal sequence W distributed to the UE and a summation of the multiplication performed between the Y′ and the conjugate of the orthogonal sequence W is performed, wherein
this step can be represented by the formula (2):
Y 1 ″=ΣY′W* (2)
wherein the W is the orthogonal sequence distributed to the UE and can be W 0 , W 1 or W 2 ; and the Y 1 ″ is the result obtained by performing a multiplication between the Y′ and the conjugate of the W and performing a summation of the multiplication performed between the Y′ and the conjugate of the W.
Step 104 : a multiplication is performed between the Y′ and the conjugate of the orthogonal sequence W n and a summation of the multiplication performed between the Y′ and the conjugate of the orthogonal sequence W n is performed, wherein
this step can be represented by the formula (3):
Y 2 ″=ΣY′Wn* (3)
wherein the W n is preferably W 3 =[+1 +1 −1 −1], and Y 2 ″ is the result obtained by performing a multiplication between the Y′ and the conjugate of the W n and performing a summation of the multiplication performed between the Y′ and the conjugate of the W n .
Step 105 : the modulus of the Y 1 ″ is squared to obtain the P s , the modulus of the Y 2 ″ is squared to obtain the P n , and the ratio of the P s to the P n is calculated;
this step can be represented by the formula (4):
P s =|Y 1 ″| 2 , P n =|Y 2 ″| 2 and f=P s /P n (4)
wherein f is the ratio of the P s to the P n .
Step 106 : the f is compared with a predetermined threshold f 1 and a corresponding detection result is determined according to the comparison result.
In the present disclosure, the predetermined threshold f 1 is the presented data predetermined and can ensure that: under the lowest signal to noise ratio required by the system, when the UE does not send a PUCCH in a format of 1, 1a or 1b, the possibility that the eNodeB detects the PUCCH in the format of 1, 1a or 1b sent by the UE is less than 0.01; when the UE sends a PUCCH in a format of 1, 1a or 1b, the possibility that the eNodeB detects the PUCCH in the format of 1, 1a or 1b sent by the UE is more than 0.99.
To implement the method, the present disclosure further provides a device for detecting a signal in an LTE system, as shown in FIG. 2 , the device includes: a receiving module, a power calculating module, a ratio calculating module and a comparing module, wherein
the receiving module is arranged to receive the data part of a signal sent by a UE on a channel resource and send the received data part of the signal sent by the UE on the channel resource to the power calculating module;
the power calculating module is arranged to calculate P s and P n according to the data part sent by the receiving module, a CAZAC sequence distributed to the UE and an orthogonal sequence W distributed to the UE, and a sequence W n which is orthogonal to the W and stored by the eNodeB, and send the calculation result to the ratio calculating module;
wherein P s is calculated by the power calculating module specifically in the following way: performing a multiplication between the data part of the signal sent by the UE on the channel resource and the conjugate of the CAZAC sequence distributed to the UE and performing a summation of the multiplication to obtain a summation result, then performing a multiplication between the obtained summation result and the conjugate of the orthogonal sequence W distributed to the UE and performing a summation of the multiplication performed between the obtained summation result and the conjugate of the orthogonal sequence W, and squaring the modulus of the result of the second summation to obtain P s ;
P n is calculated by the power calculating module specifically in the following way: performing a multiplication between the data part of the signal sent by the UE on the channel resource and the conjugate of the CAZAC sequence distributed to the UE and performing a summation of the multiplication to obtain a summation result, then performing a multiplication between the obtained the summation result and the conjugate of the sequence W n and performing a summation of the multiplication performed between the obtained the summation result and the conjugate of the sequence W n , and squaring the modulus of the second summation result to obtain P n ;
the ratio calculating module is arranged to calculate the ratio of P s to P n sent by the power calculating module and send the calculated ratio to the comparing module; and
the comparing module is arranged to store a predetermined threshold, comparing the ratio sent by the ratio calculating module with the predetermined threshold, and determining a corresponding detection result according to different comparison results.
In addition, the power calculating module further includes a multiplication and summation module and a modulus squaring module, wherein
the multiplication and summation module is arranged to perform a multiplication between the data part sent by the receiving module and the conjugate of the CAZAC sequence stored by the eNodeB and distributed to the UE and perform a summation of the multiplication to obtain a summation result, then perform a multiplication between the obtained summation result and the conjugate of the orthogonal sequence W distributed to the UE and stored by the eNodeB and perform a summation of the multiplication performed between the obtained summation result and the conjugate of the orthogonal sequence W to get a final calculation result, and send the final calculation result to the modulus squaring module; or
the multiplication and summation module is arranged to perform a multiplication between the data part sent by the receiving module and the conjugate of the CAZAC sequence stored by the eNodeB and distributed to the UE and perform a summation of the multiplication to obtain a summation result, then perform a multiplication between the obtained summation result and the conjugate of the sequence W n stored by the eNodeB and perform a summation of the multiplication performed between the obtained summation result and the conjugate of the sequence W n to get a final calculation result, and send the final calculation result to the modulus squaring module; and
the modulus squaring module is arranged to square the modulus of the result sent by the multiplication and summation module, and send the calculation result to the ratio calculating module;
correspondingly, the ratio calculating module is further arranged to calculate the ratio of P s to P n sent by the modulus squaring module, and send the obtained ratio by calculation to the comparing module.
The present disclosure is further described below with reference to three embodiments in details.
Embodiment 1
In the embodiment, when the UE is in a scheduling request period, the data part which belongs to a signal sent by a UE on a channel resource CH 1 and is received by an eNodeB is Y, and the orthogonal sequence distributed to the UE is W 0 =[+1 +1 +1 +1]. The detection result determined by the embodiment is to determine whether the UE sends a scheduling request so as to determine whether the eNodeB needs to reply to the scheduling request.
The implementation flow of the embodiment is as follows: a multiplication is performed between the Y and the conjugate of the CAZAC sequence distributed to the UE and a summation of the multiplication is performed to obtain Y′; a multiplication is performed between the Y′ and the conjugate of the W 0 and a summation of the multiplication is performed to obtain Y 1 ″; a multiplication is performed between the Y′ and the conjugate of the sequence W n and a summation of the multiplication is performed to obtain Y 2 ″; the modulus of the Y 1 ″ is squared to obtain P s ; the modulus of the Y 2 ″ is squared to obtain P n ; the ratio of the P s to the P n is calculated to obtain f; the f is compared with the predetermined threshold f 1 , if the f is more than or equal to the f 1 , it is determined that the UE sends the scheduling request, and the eNodeB needs to reply to the scheduling request; if the f is less than the f 1 , it is determined that the UE does not send the scheduling request and the eNodeB does not need to reply to the scheduling request and can continuously send subsequent messages.
Embodiment 2
In the embodiment, when the UE is in a feedback period, the data part which belongs to a signal sent by a UE on a channel resource CH 2 and is received by an eNodeB is Y, and the orthogonal sequence distributed to the UE is W 1 =[+1 −1 +1 −1]. The detection result determined by the embodiment is to determine whether the CTX occurs to the UE or DTX.
The implementation flow of the embodiment is as follows: a multiplication is performed between the Y and the conjugate of the CAZAC sequence distributed to the UE and a summation of the multiplication is performed to obtain Y′; a multiplication is performed between the Y′ and the conjugate of the W 1 and summation of the multiplication is performed to obtain Y 1 ″; a multiplication is performed between the Y′ and the conjugate of the sequence W n and a summation of the multiplication is performed to obtain Y 2 ″; the modulus of the Y 1 ″ is squared to obtain P s ; the modulus of the Y 2 ″ is squared to obtain P n ; the ratio of the P s to the P n is calculated to obtain f; the f is compared with the predetermined threshold f 1 , if the f is more than or equal to the f 1 , it is determined that the CTX occurs to the UE; and if the f is less than the f 1 , it is determined that DTX occurs to the UE and the eNodeB needs to resend the message which the UE fails to receive.
Embodiment 3
In the embodiment, when the UE is in both the scheduling request period and the feedback period, the channel resource of the signal which is sent from the UE to the eNodeB in the scheduling request period is CH 1 and the channel resource of the signal sent from the UE to the eNodeB in the feedback period is CH 2 ; correspondingly, the data parts on the channel resource CH 1 and the channel resource CH 2 are Y; and the orthogonal sequence distributed to the UE is W 2 =[+1 −1 −1 +1]. Here, the values of the data parts Y on the channel resource CH 1 and CH 2 are different. The detection result determined by the embodiment is to determine whether the UE sends the scheduling request and whether the CTX occurs to the UE or DTX.
The implementation flow of this embodiment is as follows.
Step 1: the eNodeB detects the signal sent by the UE in the scheduling request period at first;
specifically, a multiplication is performed between the data part Y of the signal sent by the UE on the channel resource CH 1 and the conjugate of the CAZAC sequence distributed to the UE and a summation of the multiplication performed between the data part Y and the conjugate of the CAZAC sequence is performed to obtain Y′; a multiplication is performed between the Y′ and the conjugate of the W 2 and a summation of the multiplication performed between the Y′ and the conjugate of the W 2 is performed to obtain Y 1 ″; a multiplication is performed between the Y′ and the conjugate of the sequence W n and a summation of the multiplication performed between the Y′ and the conjugate of the sequence W n is performed to obtain Y 2 ″; the modulus of the Y 1 ″ is squared to obtain P s ; the modulus of the Y 2 ″ is squared to obtain P n ; the ratio of P s to P n is calculated to obtain f; the f is compared with the predetermined threshold f 1 , if f is more than or equal to f 1 , it is determined that the UE sends the scheduling request and CTX occurs to the UE and the signal detection is ended; and if f is less than f 1 , step 2 is executed.
Step 2: the eNodeB detects the signal sent by the UE in the feedback period;
specifically, a multiplication is performed between the data part Y of the signal sent by the UE on the channel resource CH 2 and the conjugate of the CAZAC sequence distributed to the UE and a summation of the multiplication performed between the data part Y and the conjugate of the CAZAC sequence is performed to obtain Y′; a multiplication is performed between the Y′ and the conjugate of the W 2 and a summation of the multiplication performed between the Y′ and the conjugate of the W 2 is performed to obtain Y 1 ″; a multiplication is performed between the Y′ and the conjugate of the sequence W n and summation of the multiplication performed between the Y′ and the conjugate of the sequence W n is performed to obtain Y 2 ″; the modulus of the Y 1 ″ is squared to obtain P s ; the modulus of Y 2 ″ is squared to obtain P n ; the ratio of P s and P n is calculated to obtain f; the f is compared with the is predetermined threshold f 1 , if f is more than or equal to f 1 , it is determined that CTX occurs to the UE and does not send the scheduling request; and if f is less than f 1 , it is determined that DTX occurs to the UE and does not send the scheduling request. The value of the predetermined threshold f 1 here is different from that of the predetermined threshold f 1 in step 1.
The described above are only preferred embodiments of the present disclosure, and not intended to limit the scope of protection of the present disclosure. Any modifications, equivalent replacements, improvements and the like within the spirit and principle of the present disclosure shall fall within the scope of protection of the present disclosure. | The present disclosure discloses a method for detecting a signal in an LTE system, the method includes that: an eNodeB calculates a signal power P s and a noise power P n according to the data part of a signal sent by a UE on a channel resource, a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence, an orthogonal sequence W distributed to the UE, and a sequence W n orthogonal to the W stored by itself; and the ratio of P s to P n is compared with a predetermined threshold and a corresponding detection result is determined according to the comparison result. The present disclosure further discloses a device for detecting a signal in an LTE system. The method and device can be used for accurately, simply and easily detecting whether the UE initiates a scheduling request or whether DTX occurs to the UE, so that the eNodeB can determine to whether to continuously send a subsequent message or whether to resend the message which the UE has failed to receive, thereby improving the scheduling performance of the eNodeB. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation application of U.S. patent application Ser. No. 12/182,102 filed Jul. 29, 2008, which is a continuation application of U.S. patent application Ser. No. 11/544,768 filed on Oct. 10, 2006, now U.S. Pat. No. 7,425,047, all of which are herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of inkjet printers. In particular, the invention relates to inkjet printers that have printheads with a number of separate printhead integrated circuits (IC's) defining the nozzles that eject the ink or other printing fluid.
CO-PENDING APPLICATIONS
[0003] The following applications have been filed by the Applicant simultaneously with the present application:
[0000]
7,491,911
11/544,764
11/544,765
11/544,772
11/544,773
11/544,774
11/544,775
7,425,048
11/544,766
11/544,767
7,384,128
11/544,770
11/544,769
11/544,777
7,413,288
[0004] The disclosures of these co-pending applications are incorporated herein by reference.
CROSS REFERENCES TO RELATED APPLICATIONS
[0005] Various methods, systems and apparatus relating to the present invention are disclosed in the following US patents/patent applications filed by the applicant or assignee of the present invention:
[0000]
6,750,901
6,476,863
6,788,336
7,249,108
6,566,858
6,331,946
6,246,970
6,442,525
7,346,586
09/505,951
6,374,354
7,246,098
6,816,968
6,757,832
6,334,190
6,745,331
7,249,109
7,197,642
7,093,139
7,509,292
10/636,283
10/866,608
7,210,038
7,401,223
10/940,653
10/942,858
7,364,256
7,258,417
7,293,853
7,328,968
7,270,395
7,461,916
7,510,264
7,334,864
7,255,419
7,284,819
7,229,148
7,258,416
7,273,263
7,270,393
6,984,017
7,347,526
7,357,477
7,465,015
7,364,255
7,357,476
11/003,614
7,284,820
7,341,328
7,246,875
7,322,669
7,445,311
7,452,052
7,455,383
7,448,724
7,441,864
11/482,975
11/482,970
11/482,968
11/482,972
11/482,971
11/482,969
7,506,958
7,472,981
7,448,722
7,575,297
7,438,381
7,441,863
7,438,382
7,425,051
7,399,057
11/246,671
11/246,670
11/246,669
7,448,720
7,448,723
7,445,310
7,399,054
7,425,049
7,367,648
7,370,936
7,401,886
7,506,952
7,401,887
7,384,119
7,401,888
7,387,358
7,413,281
7,530,663
7,467,846
11/482,962
11/482,963
11/482,956
11/482,954
11/482,974
11/482,957
11/482,987
11/482,959
11/482,960
11/482,961
11/482,964
11/482,965
7,510,261
11/482,973
7,581,812
11/495,816
11/495,817
6,623,101
6,406,129
6,505,916
6,457,809
6,550,895
6,457,812
7,152,962
6,428,133
7,204,941
7,282,164
7,465,342
7,278,727
7,417,141
7,452,989
7,367,665
7,138,391
7,153,956
7,423,145
7,456,277
7,550,585
7,122,076
7,148,345
11/172,816
7,470,315
7,572,327
11/482,990
11/482,986
11/482,985
11/454,899
7,416,280
7,252,366
7,488,051
7,360,865
11/482,967
11/482,966
11/482,988
11/482,989
7,438,371
7,465,017
7,441,862
11/293,841
7,458,659
7,455,376
11/124,158
11/124,196
11/124,199
11/124,162
11/124,202
11/124,197
11/124,154
11/124,198
7,284,921
11/124,151
7,407,257
7,470,019
11/124,175
7,392,950
11/124,149
7,360,880
7,517,046
7,236,271
11/124,174
11/124,194
11/124,164
7,465,047
11/124,195
11/124,166
11/124,150
11/124,172
11/124,165
7,566,182
11/124,185
11/124,184
11/124,182
11/124,201
11/124,171
11/124,181
11/124,161
7,595,904
11/124,191
11/124,159
7,370,932
7,404,616
11/124,187
11/124,189
11/124,190
7,500,268
7,558,962
7,447,908
11/124,178
11/124,177
7,456,994
7,431,449
7,466,444
11/124,179
11/124,169
11/187,976
11/188,011
7,562,973
7,530,446
11/228,540
11/228,500
11/228,501
11/228,530
11/228,490
11/228,531
11/228,504
11/228,533
11/228,502
11/228,507
11/228,482
11/228,505
11/228,497
11/228,487
11/228,529
11/228,484
7,499,765
11/228,518
11/228,536
11/228,496
7,558,563
11/228,506
11/228,516
11/228,526
11/228,539
11/228,538
11/228,524
11/228,523
7,506,802
11/228,528
11/228,527
7,403,797
11/228,520
11/228,498
11/228,511
11/228,522
11/228,537
11/228,534
11/228,491
11/228,499
11/228,509
11/228,492
7,558,599
11/228,510
11/228,508
11/228,512
11/228,514
11/228,494
7,438,215
11/228,486
11/228,481
7,575,172
7,357,311
7,380,709
7,428,986
7,403,796
7,407,092
11/228,513
11/228,503
7,469,829
11/228,535
7,558,597
7,558,598
6,238,115
6,386,535
6,398,344
6,612,240
6,752,549
6,805,049
6,971,313
6,899,480
6,860,664
6,925,935
6,966,636
7,024,995
7,284,852
6,926,455
7,056,038
6,869,172
7,021,843
6,988,845
6,964,533
6,981,809
7,284,822
7,258,067
7,322,757
7,222,941
7,284,925
7,278,795
7,249,904
7,152,972
11/246,687
11/246,718
7,322,681
11/246,686
11/246,703
11/246,691
7,510,267
7,465,041
11/246,712
7,465,032
7,401,890
7,401,910
7,470,010
11/246,702
7,431,432
7,465,037
7,445,317
7,549,735
7,597,425
11/246,674
11/246,667
7,156,508
7,159,972
7,083,271
7,165,834
7,080,894
7,201,469
7,090,336
7,156,489
7,413,283
7,438,385
7,083,257
7,258,422
7,255,423
7,219,980
7,591,533
7,416,274
7,367,649
7,118,192
10/760,194
7,322,672
7,077,505
7,198,354
7,077,504
10/760,189
7,198,355
7,401,894
7,322,676
7,152,959
7,213,906
7,178,901
7,222,938
7,108,353
7,104,629
7,455,392
7,370,939
7,429,095
7,404,621
7,261,401
7,461,919
7,438,388
7,328,972
7,322,673
7,303,930
7,401,405
7,464,466
7,464,465
7,246,886
7,128,400
7,108,355
6,991,322
7,287,836
7,118,197
7,575,298
7,364,269
7,077,493
6,962,402
10/728,803
7,147,308
7,524,034
7,118,198
7,168,790
7,172,270
7,229,155
6,830,318
7,195,342
7,175,261
7,465,035
7,108,356
7,118,202
7,510,269
7,134,744
7,510,270
7,134,743
7,182,439
7,210,768
7,465,036
7,134,745
7,156,484
7,118,201
7,111,926
7,431,433
7,018,021
7,401,901
7,468,139
11/188,017
7,128,402
7,387,369
7,484,832
11/490,041
7,506,968
7,284,839
7,246,885
7,229,156
7,533,970
7,467,855
7,293,858
7,258,427
11/097,308
7,448,729
7,246,876
7,431,431
7,419,249
7,377,623
7,328,978
7,334,876
7,147,306
11/482,953
11/482,977
09/575,197
7,079,712
6,825,945
7,330,974
6,813,039
6,987,506
7,038,797
6,980,318
6,816,274
7,102,772
7,350,236
6,681,045
6,728,000
7,173,722
7,088,459
09/575,181
7,068,382
7,062,651
6,789,194
6,789,191
6,644,642
6,502,614
6,622,999
6,669,385
6,549,935
6,987,573
6,727,996
6,591,884
6,439,706
6,760,119
7,295,332
6,290,349
6,428,155
6,785,016
6,870,966
6,822,639
6,737,591
7,055,739
7,233,320
6,830,196
6,832,717
6,957,768
7,456,820
7,170,499
7,106,888
7,123,239
10/727,181
10/727,162
7,377,608
7,399,043
7,121,639
7,165,824
7,152,942
10/727,157
7,181,572
7,096,137
7,302,592
7,278,034
7,188,282
7,592,829
10/727,180
10/727,179
10/727,192
10/727,274
10/727,164
7,523,111
7,573,301
10/727,158
10/754,536
10/754,938
10/727,160
10/934,720
7,171,323
7,278,697
7,360,131
7,519,772
7,328,115
7,369,270
6,795,215
7,070,098
7,154,638
6,805,419
6,859,289
6,977,751
6,398,332
6,394,573
6,622,923
6,747,760
6,921,144
10/884,881
7,092,112
7,192,106
7,457,001
7,173,739
6,986,560
7,008,033
7,551,324
7,222,780
7,270,391
7,525,677
7,388,689
7,571,906
7,195,328
7,182,422
7,374,266
7,427,117
7,448,707
7,281,330
10/854,503
7,328,956
10/854,509
7,188,928
7,093,989
7,377,609
7,600,843
10/854,498
10/854,511
7,390,071
10/854,525
10/854,526
7,549,715
7,252,353
10/854,515
7,267,417
10/854,505
7,517,036
7,275,805
7,314,261
7,281,777
7,290,852
7,484,831
10/854,523
10/854,527
7,549,718
10/854,520
10/854,514
7,557,941
10/854,499
10/854,501
7,266,661
7,243,193
10/854,518
10/934,628
7,163,345
7,322,666
7,465,033
7,452,055
7,470,002
11/293,833
7,475,963
7,448,735
7,465,042
7,448,739
7,438,399
11/293,794
7,467,853
7,461,922
7,465,020
11/293,830
7,461,910
11/293,828
7,270,494
11/293,823
7,475,961
7,547,088
11/293,815
11/293,819
11/293,818
11/293,817
11/293,816
11/482,978
7,448,734
7,425,050
7,364,263
7,201,468
7,360,868
7,234,802
7,303,255
7,287,846
7,156,511
10/760,264
7,258,432
7,097,291
10/760,222
10/760,248
7,083,273
7,367,647
7,374,355
7,441,880
7,547,092
10/760,206
7,513,598
10/760,270
7,198,352
7,364,264
7,303,251
7,201,470
7,121,655
7,293,861
7,232,208
7,328,985
7,344,232
7,083,272
7,311,387
11/014,764
11/014,763
7,331,663
7,360,861
7,328,973
7,427,121
7,407,262
7,303,252
7,249,822
7,537,309
7,311,382
7,360,860
7,364,257
7,390,075
7,350,896
7,429,096
7,384,135
7,331,660
7,416,287
7,488,052
7,322,684
7,322,685
7,311,381
7,270,405
7,303,268
7,470,007
7,399,072
7,393,076
11/014,750
7,588,301
7,249,833
7,524,016
7,490,927
7,331,661
7,524,043
7,300,140
7,357,492
7,357,493
7,566,106
7,380,902
7,284,816
7,284,845
7,255,430
7,390,080
7,328,984
7,350,913
7,322,671
7,380,910
7,431,424
7,470,006
7,585,054
7,347,534
7,441,865
7,469,989
7,367,650
7,469,990
7,441,882
7,556,364
7,357,496
7,467,863
7,431,440
7,431,443
7,527,353
7,524,023
7,513,603
7,467,852
7,465,045
11/482,982
11/482,983
11/482,984
11/495,818
11/495,819
BACKGROUND OF THE INVENTION
[0006] Inkjet printers eject drops of ink through an array of nozzles to effect printing on a media substrate. The nozzles are typically formed on a silicon wafer substrate using semiconductor fabrication techniques. Each nozzle is a MEMS (micro electro-mechanical systems) device driven by associated drive circuitry formed on the same silicon wafer substrate. The MEMS nozzle devices and associated drive circuitry formed on a single nozzle is commonly referred to as a printhead integrated circuit (IC).
[0007] Some inkjet printheads have a single printhead IC. These are scanning type printheads that traverse back and forth across the width of a page as the printer indexes the length of the page past the printhead. The Applicant has developed a range of pagewidth printheads that have a nozzle array as long as the printing width of the page. These printheads remain stationary in the printer as the page is fed past. This allows much higher print speeds but is more complicated in terms of controlling the operation of a much larger array of nozzles.
[0008] The pagewidth array of nozzles is made up of a series of separate printhead IC's placed end to end. Skilled workers in this field will appreciate that more printhead IC's can be fabricated on the unprocessed circular silicon wafers if each IC is short rather than long. Furthermore, localized fabrication defects can render an entire printhead IC defective. Hence there is less chance that each individual IC will be defective if they are shorter.
[0009] The Applicant has found that it is beneficial to provide the pagewidth printhead in the form of a replaceable cartridge. If nozzle clogging or actuator burn out reduce the print quality to an unacceptable level, the user simply replaces the printhead instead of the entire printer. However, user expectation demands that the printhead replacement process be as simple and failsafe as possible. Therefore, the number of interconnections between the PEC and the printhead should be minimized.
[0010] Different printers use different PEC's to control the printhead. Different PEC's can use different interface protocols depending on the printer requirements. For example, the Applicant has developed a PEC that control the printhead IC's with a self clocking data signal. This reduces the number of connections between the PEC and the printhead IC. However, some PEC's will still use separate clock and data lines to the printhead IC's. This necessitates the fabrication of different printhead IC's for each type of PEC.
SUMMARY OF THE INVENTION
[0011] According to a first aspect, the present invention provides a printhead IC for an inkjet printer, the inkjet printer having a PEC for sending print data to the printhead IC in accordance with a predetermined data transmission protocol, the printhead IC comprising:
[0012] an array of nozzles for ejecting drops of printing fluid onto a media substrate; and,
[0013] drive circuitry for driving the array of nozzles; wherein,
[0014] the circuitry is configured to receive print data in any one of a plurality of different data transmission protocols.
[0015] Making the printhead IC's compatible with different data transmission protocols increases the versatility of the printhead IC design. A versatile design lowers the types of chip that need to be fabricated thereby lowering production costs.
[0016] Optionally, one of the data transmission protocols is a self clocking data signal and another data transmission protocol has separate clock and data signals.
[0017] Optionally, connection to a power source within the printer, the drive circuitry cycles through different operating modes until it aligns with the data transmission protocol being used by the PEC.
[0018] Optionally, the drive circuitry is configured to extract a clock signal from the data transmission from the PEC.
[0019] Optionally, the data transmission is a digital signal that has a rising edge at every clock period.
[0020] Optionally, the drive circuitry determines a data bit from every clock period by the position of the falling edge during that period.
[0021] In another aspect the present invention provides a printhead IC linked with other like printhead IC's to form a pagewidth printhead, wherein the data transmission is multi-dropped to all the printhead IC's and each printhead IC has a unique write address provided by the PEC.
[0022] Optionally, the interface between the printhead and the PEC has only two connections.
[0023] In another aspect the present invention provides a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0024] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0025] Optionally, the open actuator test circuitry generates defective nozzle feedback during print jobs.
[0026] Optionally, the open actuator test circuitry generates defective nozzle feedback within a predetermined time period after printhead operation.
[0027] Optionally, the drive circuitry has a drive FET controlling current to the resistive heater and logic for enabling the drive FET when a drive signal is received and disabling the drive FET when a drive signal and a open actuator test signal are received.
[0028] Optionally, the drive circuitry has a bleed FET that slowly drains any voltage drop across the resistive heater to zero when the drive circuitry is not receiving a drive signal or an open actuator test signal.
[0029] Optionally, the drive circuitry has a sense node between the drain of the drive FET and the resistive heater, and the open actuator test circuitry has a sense FET that is enabled when open actuator test signal is received such that the voltage at the drain of the sense FET is used to indicate whether the heater element is defective.
[0030] Optionally, the drive FET is a p-type FET.
[0031] Optionally, the drive circuitry receives the print data for the array in a plurality of sequential portions with a fire command at the end of each portion.
[0032] In another aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0033] Optionally, the drive circuitry blocks the dive pulses sent to at least some of the nozzles in the array when one or more of the temperature sensors indicate the temperature exceeds a predetermined maximum.
[0034] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0035] According to a second aspect, the present invention provides a printhead IC comprising:
[0036] an array of nozzles;
[0037] an ejection actuator corresponding to each of the nozzles respectively, the ejection actuator having a resistive heater that is activated when the actuator ejects ink through the corresponding nozzle;
[0038] drive circuitry for receiving print data and activating the actuators with drive signals in accordance with the print data; and,
[0039] open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0040] In thermal inkjet printheads and thermal bend inkjet printheads, the vast majority of failures are the result of the resistive heater burning out and breaking or ‘going open circuit’. Nozzles may fail to eject ink because of clogging but this is not a ‘dead nozzle’ and may be recovered through the printer maintenance regime. By determining which nozzles are dead with an inbuilt circuit, the print engine controller can periodically update its dead nozzle map and thereby extend to operational life of the printhead.
[0041] Preferably the open actuator test circuitry generates defective nozzle feedback during print jobs. In a further preferred form the open actuator test circuitry generates defective nozzle feedback within a predetermined time period after printhead operation. In a particularly preferred form, the open actuator test circuitry generates defective nozzle feedback between each page of a print job. Preferably the drive circuitry has an actuator FET (field effect transistor) that is enabled by a drive signal to open the resistive heater to a drive voltage, and the open actuator test circuitry has NAND logic with the drive signal and an actuator test signal as inputs and outputs to the gate of the actuator FET. Preferably, the open actuator test circuitry has a sense FET with a source connected to the high voltage side of the resistive heater and a drain connected to a sense electrode, the sense FET being enabled by the test signal such that a low voltage output to the sense electrode is fed back as a functional actuator and a high voltage output to the sense electrode is fed back as a defective actuator.
[0042] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0043] Optionally, the open actuator test circuitry generates defective nozzle feedback during print jobs.
[0044] Optionally, the open actuator test circuitry generates defective nozzle feedback within a predetermined time period after printhead operation.
[0045] Optionally, the open actuator test circuitry generates defective nozzle feedback between each page of a print job.
[0046] Optionally, the drive circuitry has a drive FET controlling current to the resistive heater and logic for enabling the drive FET when a drive signal is received and disabling the drive FET when a drive signal and a open actuator test signal are received.
[0047] Optionally, the drive circuitry has a bleed FET that slowly drains any voltage drop across the resistive heater to zero when the drive circuitry is not receiving a drive signal or an open actuator test signal.
[0048] Optionally, the drive circuitry has a sense node between the drain of the drive FET and the resistive heater, and the open actuator test circuitry has a sense FET that is enabled when open actuator test signal is received such that the voltage at the drain of the sense FET is used to indicate whether the heater element is defective.
[0049] Optionally, the drive FET is a p-type FET.
[0050] Optionally, the drive circuitry receives the print data for the array in a plurality of sequential portions with a fire command at the end of each portion.
[0051] In a further aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors for sensing the temperature of the printhead IC within each of the regions respectively.
[0052] Optionally, the drive circuitry adjusts the drive pulses sent to the nozzles in accordance with the temperature of the printing fluid within the nozzles.
[0053] Optionally, the drive circuitry blocks the dive pulses sent to at least some of the nozzles in the array when one or more of the temperature sensors indicate the temperature exceeds a predetermined maximum.
[0054] Optionally, the drive pulses consist of ejection pulses with sufficient energy to eject printing fluid from the nozzles designated to fire at that time, and sub-ejection pulses with insufficient energy to eject printing fluid from the nozzles not designated to fire at that time.
[0055] Optionally, during use the drive circuitry adjusts the drive pulse profile in response to the temperature sensor output.
[0056] Optionally, during use, the temperature sensor can be de-activated after a period of use.
[0057] Optionally, the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0058] Optionally, each row of nozzles is divided into a plurality of groups, each having at least one nozzle the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0059] Optionally, during use the drive circuitry actuates the nozzles in the row in accordance with a firing sequence, the firing sequence enabling the nozzles in each group to eject printing fluid simultaneously, and enabling each of the groups to eject printing fluid in succession such that, the nozzles in each group are spaced from each other by at least a predetermined minimum number of nozzles and, each of the nozzles in a group is spaced from the nozzles in the subsequently enabled group by at least the predetermined minimum number of nozzles.
[0060] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0061] According to a third aspect, the present invention provides a printhead IC comprising:
[0062] an array of nozzles;
[0063] drive circuitry for receiving print data and fire commands from a print engine controller; wherein during use,
[0064] the drive circuitry receives the print data for the array in a plurality of sequential portions with a fire command at the end of each portion.
[0065] Instead of providing a shift register for each nozzle in the array, the printhead IC only has enough dot data shift registers for a portion of the nozzle array which it fires while the shift register load with the dot data for the next portion of the array. This moves the shift register out of the unit cell (the smallest repeating unit of nozzles and corresponding ink chamber, actuator and drive circuitry) which allows the drive FET to be larger while not impacting on the nozzle density. As discussed above, a larger drive FET can generate a drive pulse at higher power levels for more efficient drop ejection.
[0066] Preferably, the array is configured into rows and columns, and the sequential portions are the nozzles in each individual row such that the rows eject printing fluid one row at a time. In a further preferred form, the drive circuitry is configured to fire the rows in a predetermined sequence and the print engine controller sends the print data for each row to the drive circuitry in the predetermined sequence. In a particularly preferred form, the print data for the next row in the predetermined sequence is loaded as the previous row is fired. Preferably, the nozzles in each of the rows eject the same type of printing fluid.
[0067] Optionally, the array is configured into rows and columns, and the sequential portions are the nozzles in each individual row such that the rows eject printing fluid one row at a time.
[0068] Optionally, the drive circuitry is configured to fire the rows in a predetermined sequence and the print engine controller sends the print data for each row to the drive circuitry in the predetermined sequence.
[0069] Optionally, the print data for the next row in the predetermined sequence is loaded as the previous row is fired.
[0070] Optionally, the nozzles in each of the rows eject the same type of printing fluid.
[0071] In a further aspect there is provided a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0072] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0073] Optionally, the open actuator test circuitry generates defective nozzle feedback during print jobs.
[0074] In a further aspect there is provided a printhead IC according further comprising a plurality of temperature sensors for sensing the temperature of the printhead IC within each of the regions respectively.
[0075] Optionally, the drive circuitry adjusts the drive pulses sent to the nozzles in accordance with the temperature of the printing fluid within the nozzles.
[0076] Optionally, the drive circuitry blocks the dive pulses sent to at least some of the nozzles in the array when one or more of the temperature sensors indicate the temperature exceeds a predetermined maximum.
[0077] Optionally, the drive pulses consist of ejection pulses with sufficient energy to eject printing fluid from the nozzles designated to fire at that time, and sub-ejection pulses with insufficient energy to eject printing fluid from the nozzles not designated to fire at that time.
[0078] Optionally, during use the drive circuitry adjusts the drive pulse profile in response to the temperature sensor output.
[0079] Optionally, during use, the temperature sensor can be de-activated after a period of use.
[0080] Optionally, the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0081] Optionally, each row of nozzles is divided into a plurality of groups, each having at least one nozzle the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0082] Optionally, during use the drive circuitry actuates the nozzles in the row in accordance with a firing sequence, the firing sequence enabling the nozzles in each group to eject printing fluid simultaneously, and enabling each of the groups to eject printing fluid in succession such that, the nozzles in each group are spaced from each other by at least a predetermined minimum number of nozzles and, each of the nozzles in a group is spaced from the nozzles in the subsequently enabled group by at least the predetermined minimum number of nozzles.
[0083] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0084] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0085] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0086] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0087] According to a fourth aspect, the present invention provides a printhead IC comprising:
[0088] an array of nozzles having a plurality of adjacent regions; and,
[0089] drive circuitry for sending an electrical pulse to each of the nozzles individually such that they eject a drop of printing fluid; and,
[0090] a plurality of temperature sensors for sensing the temperature of the printhead IC within each of the regions respectively.
[0091] Monitoring the temperature across the printhead IC with several sensors gives the drive circuitry a temperature profile of the ink in different regions. Using the feedback from the sensors, the drive pulse sent to the nozzles in each region can be adjusted to best suit the current viscosity of the ink. By compensating for any ink viscosity differences, the drop ejection characteristics are kept uniform across the entire printhead IC, and thereby the whole pagewidth printhead. As discussed above, uniform drop ejection improves the print quality.
[0092] Preferably, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the electrical pulses sent to the nozzles in the region currently operating in that temperature zone. In a further preferred form the pulse profile for each temperature zone differs in its duration. In a particularly preferred form, the associated drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds. In some embodiments, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time. In specific forms of this embodiment, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence. In some versions of this embodiment, the associated drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0093] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the electrical pulses sent to the nozzles in the region currently operating in that temperature zone.
[0094] Optionally, the pulse profile for each temperature zone differs in its duration.
[0095] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0096] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0097] Optionally, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0098] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0099] Optionally, the open actuator test circuitry generates defective nozzle feedback during print jobs.
[0100] In a further aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0101] Optionally, the drive circuitry adjusts the drive pulses sent to the nozzles in accordance with the temperature of the printing fluid within the nozzles.
[0102] Optionally, the drive circuitry blocks the dive pulses sent to at least some of the nozzles in the array when one or more of the temperature sensors indicate the temperature exceeds a predetermined maximum.
[0103] Optionally, the drive pulses consist of ejection pulses with sufficient energy to eject printing fluid from the nozzles designated to fire at that time, and sub-ejection pulses with insufficient energy to eject printing fluid from the nozzles not designated to fire at that time.
[0104] Optionally, during use the drive circuitry adjusts the drive pulse profile in response to the temperature sensor output.
[0105] Optionally, during use, the temperature sensor can be de-activated after a period of use.
[0106] Optionally, the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0107] Optionally, each row of nozzles is divided into a plurality of groups, each having at least one nozzle the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0108] Optionally, during use the drive circuitry actuates the nozzles in the row in accordance with a firing sequence, the firing sequence enabling the nozzles in each group to eject printing fluid simultaneously, and enabling each of the groups to eject printing fluid in succession such that, the nozzles in each group are spaced from each other by at least a predetermined minimum number of nozzles and, each of the nozzles in a group is spaced from the nozzles in the subsequently enabled group by at least the predetermined minimum number of nozzles.
[0109] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0110] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0111] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0112] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0113] According to a fifth aspect, the present invention provides a printhead IC comprising:
[0114] an array of nozzles; and,
[0115] drive circuitry for sending an drive pulse to each of the nozzles individually such that they eject a drop of printing fluid; wherein,
[0116] the drive circuitry adjusts the drive pulses sent to the nozzles in accordance with the temperature of the printing fluid within the nozzles.
[0117] Monitoring the temperature of individual printhead IC's allows the drive circuitry to compensate for any differences in ink viscosity between different printhead IC's of the pagewidth printhead. By compensating for any ink viscosity differences, the drop ejection characteristics are kept uniform across the entire printhead to improve the print quality.
[0118] Preferably, the printhead IC further comprises a plurality of temperature sensors, each for sensing the temperature the nozzles within a region of the array such that the drive pulse for the nozzles in one region differs from the drive pulse for the nozzles in another region in response to a temperature difference between the regions. Preferably, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone. In a further preferred form the pulse profile for each temperature zone differs in its duration. In a particularly preferred form, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds. In some embodiments, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time. In specific forms of this embodiment, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence. In some versions of this embodiment, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0119] In a further aspect the present invention provides a printhead IC further comprises a plurality of temperature sensors, each for sensing the temperature the nozzles within a region of the array such that the drive pulse for the nozzles in one region differs from the drive pulse for the nozzles in another region in response to a temperature difference between the regions.
[0120] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0121] Optionally, the pulse profile for each temperature zone differs in its duration.
[0122] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0123] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0124] Optionally, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0125] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0126] In a further aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0127] In a further aspect the present invention provides a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0128] Optionally, the drive circuitry blocks the drive pulses sent to at least some of the nozzles in the array when one or more of the temperature sensors indicate the temperature exceeds a predetermined maximum.
[0129] Optionally, the drive pulses consist of ejection pulses with sufficient energy to eject printing fluid from the nozzles designated to fire at that time, and sub-ejection pulses with insufficient energy to eject printing fluid from the nozzles not designated to fire at that time.
[0130] Optionally, during use the drive circuitry adjusts the drive pulse profile in response to the temperature sensor output.
[0131] Optionally, during use, the temperature sensor can be de-activated after a period of use.
[0132] Optionally, the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0133] Optionally, each row of nozzles is divided into a plurality of groups, each having at least one nozzle the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0134] Optionally, during use the drive circuitry actuates the nozzles in the row in accordance with a firing sequence, the firing sequence enabling the nozzles in each group to eject printing fluid simultaneously, and enabling each of the groups to eject printing fluid in succession such that, the nozzles in each group are spaced from each other by at least a predetermined minimum number of nozzles and, each of the nozzles in a group is spaced from the nozzles in the subsequently enabled group by at least the predetermined minimum number of nozzles.
[0135] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0136] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0137] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0138] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0139] According to a sixth aspect, the present invention provides a printhead IC comprising:
[0140] an array of nozzles; and,
[0141] drive circuitry for sending an drive pulse to each of the nozzles individually such that they eject a drop of printing fluid; and,
[0142] a temperature sensor for sensing the temperature of printing fluid within the array; wherein,
[0143] the drive circuitry blocks the drive pulses sent to at least some of the nozzles in the array when the sensor indicates the temperature exceeds a predetermined maximum.
[0144] De-activating the heaters at a maximum temperature effectively aborts the print job but prevents nozzle burn-out. An overheating safeguard allows the nozzles to be recovered when the problem has been remedied.
[0145] Preferably, the drive circuitry reduces the duration the drive pulses as the temperatures of the printing fluid approaches the predetermined maximum such that the direction at the predetermined maximum is zero.
[0146] Monitoring the temperature of individual printhead IC's allows the drive circuitry to compensate for any differences in ink viscosity between different printhead IC's of the pagewidth printhead. By compensating for any ink viscosity differences, the drop ejection characteristics are kept uniform across the entire printhead to improve the print quality.
[0147] Preferably, the printhead IC further comprises a plurality of temperature sensors, each for sensing the temperature the nozzles within a region of the array such that the drive pulse for the nozzles in one region differs from the drive pulse for the nozzles in another region in response to a temperature difference between the regions. Preferably, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone. In some embodiments, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time. In specific forms of this embodiment, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence. In some versions of this embodiment, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0148] Optionally, the drive circuitry reduces the duration the drive pulses as the temperatures of the printing fluid approaches the predetermined maximum such that the direction at the predetermined maximum is zero.
[0149] In a further aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors, each for sensing the temperature the nozzles within a region of the array such that the drive pulse for the nozzles in one region differs from the drive pulse for the nozzles in another region in response to a temperature difference between the regions.
[0150] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0151] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0152] Optionally, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0153] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0154] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0155] In a further aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0156] In a further aspect the present invention provides a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0157] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0158] Optionally, the drive pulses consist of ejection pulses with sufficient energy to eject printing fluid from the nozzles designated to fire at that time, and sub-ejection pulses with insufficient energy to eject printing fluid from the nozzles not designated to fire at that time.
[0159] Optionally, during use the drive circuitry adjusts the drive pulse profile in response to the temperature sensor output.
[0160] Optionally, during use, the temperature sensor can be de-activated after a period of use.
[0161] Optionally, the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0162] Optionally, each row of nozzles is divided into a plurality of groups, each having at least one nozzle the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0163] Optionally, during use the drive circuitry actuates the nozzles in the row in accordance with a firing sequence, the firing sequence enabling the nozzles in each group to eject printing fluid simultaneously, and enabling each of the groups to eject printing fluid in succession such that, the nozzles in each group are spaced from each other by at least a predetermined minimum number of nozzles and, each of the nozzles in a group is spaced from the nozzles in the subsequently enabled group by at least the predetermined minimum number of nozzles.
[0164] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0165] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0166] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0167] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0168] According to a seventh aspect, the present invention provides a printhead IC comprising:
[0169] an array of nozzles; and,
[0170] drive circuitry for receiving print data and sending drive pulses to the nozzles in accordance with the print data; wherein,
[0171] the drive pulses consist of ejection pulses with sufficient energy to eject printing fluid from the nozzles designated to fire at that time, and sub-ejection pulses with insufficient energy to eject printing fluid from the nozzles not designated to fire at that time.
[0172] The drive circuitry sends an drive pulse to every nozzle in the array regardless of whether the print data has designated it to be a firing nozzle at that time. The non-firing nozzles are sent a sub-ejection pulse that is not enough to eject a drop of ink, but does maintain the temperature of the ink at the nozzle so that when next it fires, its ink temperature, and hence viscosity, is similar to that of the more frequently firing nozzles.
[0173] Preferably, the sub-ejection pulses have the same voltage and current as the ejection pulses, but a shorter duration. In a further preferred form, printhead IC further comprises a temperature sensor that has an output indicative of the temperature of at least part of the array wherein the drive circuitry sets the duration of the drive pulses to zero if the temperature sensor indicates that the temperature is above a predetermined maximum.
[0174] Preferably, the printhead IC further comprises a plurality of temperature sensors, each for sensing the temperature the nozzles within a region of the array such that the drive pulse for the nozzles in one region differs from the drive pulse for the nozzles in another region in response to a temperature difference between the regions. Preferably, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0175] Monitoring the temperature of individual printhead IC's allows the drive circuitry to compensate for any differences in ink viscosity between different printhead IC's of the pagewidth printhead. By compensating for any ink viscosity differences, the drop ejection characteristics are kept uniform across the entire printhead to improve the print quality.
[0176] In some embodiments, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time. In specific forms of this embodiment, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0177] Optionally, the sub-ejection pulses have the same voltage and current as the ejection pulses, but a shorter duration.
[0178] In a further aspect the present invention provides a printhead IC further comprising a temperature sensor that has an output indicative of the temperature of at least part of the array wherein the drive circuitry sets the duration of the drive pulses to zero if the temperature sensor indicates that the temperature is above a predetermined maximum.
[0179] In a further aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors, each for sensing the temperature the nozzles within a region of the array such that the drive pulse for the nozzles in one region differs from the drive pulse for the nozzles in another region in response to a temperature difference between the regions.
[0180] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0181] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0182] In a further aspect the present invention provides a printhead IC further comprising the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0183] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0184] In a further aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0185] In a further aspect the present invention provides a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0186] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0187] Optionally, the drive circuitry adjusts the drive pulses sent to the nozzles in accordance with the temperature of the printing fluid within the nozzles.
[0188] Optionally, during use the drive circuitry adjusts the drive pulse profile in response to the temperature sensor output.
[0189] Optionally, during use, the temperature sensor can be de-activated after a period of use.
[0190] Optionally, the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0191] Optionally, each row of nozzles is divided into a plurality of groups, each having at least one nozzle the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0192] Optionally, during use the drive circuitry actuates the nozzles in the row in accordance with a firing sequence, the firing sequence enabling the nozzles in each group to eject printing fluid simultaneously, and enabling each of the groups to eject printing fluid in succession such that, the nozzles in each group are spaced from each other by at least a predetermined minimum number of nozzles and, each of the nozzles in a group is spaced from the nozzles in the subsequently enabled group by at least the predetermined minimum number of nozzles.
[0193] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0194] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0195] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0196] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0197] According to an eighth aspect, the present invention provides a printhead IC comprising:
[0198] an array of nozzles;
[0199] associated drive circuitry for receiving print data and sending drive pulses of electrical energy to the array of nozzles in accordance with the print data; and,
[0200] a temperature sensor connected to the drive circuitry to adjust the drive pulse profile in response to the temperature sensor output; wherein during use,
[0201] the temperature sensor can be de-activated after a period of use.
[0202] A temperature sensor on each printhead IC allows the drive circuitry to adjust the drive pulses to compensate for temperature variations. However, the temperature sensor is an added power load and an additional electronic component that generates noise in the other circuits. By de-activating the sensor once the operating temperature is known, the power and noise problems created by the sensor are temporary. The temperature of the printhead IC is not likely to vary rapidly or by large amounts once it has reached its operating temperature, so it can be de-activated with a good probability that any temperature compensation to the drive pulse profile will remain correct.
[0203] Preferably, the temperature sensor periodically re-activates such that the drive circuitry can adjust the drive pulse profile if necessary. In a further preferred form, the printhead IC has a plurality of temperature sensors spaced along the array, wherein during use, one or more of the temperature sensors can be de-activated. In some embodiments, each of the plurality of temperature sensors is activated sequentially for a period of time during the print job.
[0204] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0205] Preferably, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region. In one embodiment, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated. Preferably, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone. In a further preferred form the pulse profile for each temperature zone differs in its duration. In a particularly preferred form, the associated drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds. In some embodiments, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time. In specific forms of this embodiment, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence. In some versions of this embodiment, the associated drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0206] Optionally, the temperature sensor periodically re-activates such that the drive circuitry can adjust the drive pulse profile if necessary.
[0207] In a further aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors spaced along the array, wherein during use, one or more of the temperature sensors can be de-activated.
[0208] Optionally, each of the plurality of temperature sensors is activated sequentially for a period of time during the print job.
[0209] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0210] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0211] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0212] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0213] Optionally, the pulse profile for each temperature zone differs in its duration.
[0214] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0215] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0216] Optionally, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0217] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0218] In a further aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0219] In a further aspect the present invention provides a printhead IC comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0220] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0221] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0222] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0223] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0224] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0225] According to a ninth aspect, the present invention provides an inkjet printer comprising:
[0226] an array of nozzles arranged into rows, each row of nozzles is divided into a plurality of groups, each having at least one nozzle; and,
[0227] drive circuitry for sending a drive pulse to each of the nozzles individually such that they eject a drop of printing fluid; wherein,
[0228] the drive circuitry delays sending the drive pulses to one of the groups relative to at least one of the other groups.
[0229] By firing the nozzles in stages, the rate of change of the current drawn from the power supply decreases. This in turn lowers the impedance in the circuit and therefore, the voltage sag. The minimum time available to fire all the nozzles in arrow is set by the ink refill time. In the Applicant's printhead IC designs, the ink refill can be approximately 50 microseconds. The duration of the firing pulse is about 300 to 500 nanoseconds. In a printhead IC with, say, ten rows of nozzles, each row has about 5 microseconds to fire all the nozzles. To fire the row in less time is possible but would mean the row would spend some time completely inactive in between row fires. The invention utilizes this time to stagger the nozzle firing sequence in the row and thereby smooth the increase in the current required.
[0230] Preferably, the row of nozzles is made up of a series of regions, and the sets are determined by the nozzles that are positioned within one of the regions. In a further preferred form, each row has a total time available for it to eject printing fluid from all the nozzles, and the drive pulse sent to eject printing fluid from the nozzles in one region, partially overlaps with the drive pulse sent to eject printing fluid from the nozzles of at least one other region.
[0231] Optionally, the array is made up of a series of regions, with a number of the groups from each row being within each of the regions, such that the drive circuitry starts sending the drive pulses to each of the regions sequentially.
[0232] Optionally, the drive pulses are sent to each region in a firing sequence such that only one nozzle from each group fires simultaneously, and the firing sequence for each region having the same duration such that the firing sequence from the one region, partially overlaps with more than of the firing sequences from other regions in the same row.
[0233] In a further aspect the present invention provides an inkjet printer comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0234] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0235] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0236] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0237] Optionally, drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0238] Optionally, the pulse profile for each temperature zone differs in its duration.
[0239] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0240] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0241] Optionally, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0242] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0243] Optionally, the array of nozzles and the drive circuitry is fabricated on a printhead IC, the printhead IC being mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0244] In a further aspect the present invention provides an inkjet printer further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0245] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0246] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0247] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0248] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0249] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0250] According to a tenth aspect, the present invention provides an inkjet printer comprising:
an array of nozzles arranged into rows, each row consisting of a plurality of nozzle groups, the nozzles in each group being interspersed with nozzles from the other groups; and, associated drive circuitry for actuating the nozzles in the row in accordance with a firing sequence, the firing sequence enabling the nozzles in each group to eject printing fluid simultaneously, and enabling each of the groups to eject printing fluid in succession; wherein, the nozzles in each group are spaced from each other by at least a predetermined minimum number of nozzles and, each of the nozzles in a group is spaced from the nozzles in the subsequently enabled group by at least the predetermined minimum number of nozzles.
[0254] The invention sets the nozzle firing sequence in each row such that the nozzles fire in staggered groups, the nozzles within each group can be selected so that they are not too close to a simultaneously fired nozzle, or a nozzle that is fired immediately afterwards. Staging the nozzle firings avoids the high current required for firing the whole row simultaneously. Maintaining a minimum spacing between simultaneously fired nozzles and the nozzles fired immediately after them avoids the detrimental effects of fluidic cross talk and aerodynamic interference.
[0255] It should be noted that the print data is unlikely to require every nozzle in a row to fire in the same firing sequence. However, the invention enables every nozzle to fire at a certain time within the firing sequence, regardless of whether it does fire a drop. Therefore, the spacing between simultaneously firing nozzles, or sequentially firing nozzles, will often be more than the predetermined minimum spacing, but this is not detrimental to the print quality. The invention is concerned with ensuring the spacing between two potentially interfering drops is never less than the predetermined minimum.
[0256] Preferably, the row is divided into spans having only one nozzle from every group so that the number of spans across the row equals the number of groups of nozzles. In a further preferred form, the predetermined minimum number of nozzles between sequentially enabled nozzles is a uniform shift along each span in a uniform direction, the shift being a number of nozzles that is an integer greater than one and not a factor of the number of nozzles in the span, such that, the successively enabled nozzles in each span progress toward one end of the span until there are insufficient nozzles left at the end to fill the shift, in which case, the shift is completed with nozzles at the opposite end of the span so that all the nozzles in the span are enabled once during the firing sequence.
[0257] In a particularly preferred form, the shift is the number of nozzles that is the nearest integer to the square root of the span, that is not a factor (i.e. the span can not be divisible by the shift without a remainder). The Applicant has found that this provides a maximum spacing in time and space for ejected drops.
[0258] Optionally, the row is divided into spans having only one nozzle from every group so that the number of spans across the row equals the number of groups of nozzles.
[0259] Optionally, the predetermined minimum number of nozzles between sequentially enabled nozzles is a uniform shift along each span in a uniform direction, the shift being a number of nozzles that is an integer greater than one and not a factor of the number of nozzles in the span, such that, the successively enabled nozzles in each span progress toward one end of the span until there are insufficient nozzles left at the end to fill the shift, in which case, the shift is completed with nozzles at the opposite end of the span so that all the nozzles in the span are enabled once during the firing sequence.
[0260] Optionally, the shift is the number of nozzles that is the nearest integer to the square root of the span, that is not a factor.
[0261] In a another aspect the present invention provides an inkjet printer further comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0262] Optionally, each of the plurality of temperature sensors is activated sequentially for a period of time during the print job.
[0263] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0264] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0265] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0266] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0267] Optionally, the pulse profile for each temperature zone differs in its duration.
[0268] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0269] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0270] In a further aspect the present invention provides an inkjet printer mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0271] In a further aspect the present invention provides an inkjet printer further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0272] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0273] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0274] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0275] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0276] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0277] According to an eleventh aspect, the present invention provides a printhead IC for an inkjet printer that mounts the printhead IC together with at least one other like printhead IC to provide a pagewidth printhead for printing onto a media substrate fed past the printhead in a feed direction, the printhead IC comprising:
an elongate array of nozzles, the nozzles arranged into rows, at least one of the rows having a first section positioned on a line extending perpendicular to the feed direction, a second section positioned along a parallel line displaced from the first section, and an intermediate section of nozzles extending between the first section and the second section; and, a supply conduit for providing printing fluid to the first section, the second section and the intermediate section, the supply conduit having a first portion extending perpendicular to the feed direction for supplying the first section of nozzles, a second portion extending perpendicular to the feed direction for supplying the second section of nozzles and an inclined portion for supplying the intermediate section of nozzles.
[0280] Inclining a section of the nozzle rows down to meet the drop triangle, avoids sharp corners in the corresponding supply conduit.
[0281] Preferably, the intermediate section of nozzles follows a stepped path from the first section to the section. In a further preferred form the stepped path comprises steps of two nozzles each, the two nozzles on each step being positioned on a line extending perpendicular to the feed direction. In a particularly preferred form each of the rows in the array have a first and second section extending perpendicular to the feed direction and an inclined section extending between the two. In some embodiments, the array of nozzles are fabricated on one side of a wafer substrate and the supply conduits are a series of channels etched into the opposite side of the wafer substrate. In specific embodiments, each of the supply conduits supplies printing fluid to two of the rows of nozzles.
[0282] Optionally, the intermediate section of nozzles follows a stepped path from the first section to the section.
[0283] Optionally, the stepped path comprises steps of two nozzles each, the two nozzles on each step being positioned on a line extending perpendicular to the feed direction.
[0284] Optionally, the array of nozzles are fabricated on one side of a wafer substrate and the supply conduits are a series of channels etched into the opposite side of the wafer substrate.
[0285] Optionally, each of the supply conduits supplies printing fluid to two of the rows of nozzles.
[0286] Optionally, the nozzles eject printing fluid in accordance with print data from a print engine controller, the printing fluid ejected from the intermediate section is progressively delayed with each step on the stepped path.
[0287] In another aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0288] Optionally, each of the plurality of temperature sensors is activated sequentially for a period of time during the print job.
[0289] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0290] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0291] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0292] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0293] Optionally, the pulse profile for each temperature zone differs in its duration.
[0294] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0295] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0296] In another aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0297] In another aspect the present invention provides a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0298] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0299] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0300] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0301] According to a twelfth aspect, the present invention provides a printhead IC comprising:
[0302] an array of nozzles, each with a corresponding heater to form a vapor bubble in printing fluid that causes a drop of the printing fluid to eject through the nozzle; and,
[0303] drive circuitry for generating drive pulses that energize the heaters, the drive circuitry being configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses; wherein,
[0304] the de-clog pulse has a longer duration than the printing pulse.
[0305] The bubble formed by a relatively long, low power pulse is a larger bubble. A larger bubble imparts a greater impulse to the ink and is therefore better able to de-clog the nozzle. The impulse is the pressure integrated over the bubble area and the pulse duration. During the printing mode, it is desirable to nucleate the bubble quickly to reduce the heat lost into the ink by conduction as the heater heats up to the superheated temperature. By lowering the pulse power, bubble nucleation is delayed. During the delay, the heater increases the heat conducted into the ink. The thermal energy of the ink rises and upon nucleation, the stored energy is released as a larger bubble with greater impulse.
[0306] Optionally, the de-clog pulse is preceded by a series of sub-ejection pulses that do not have sufficient energy to nucleate a bubble in the printing fluid.
[0307] Optionally, the drive circuitry sends de-clog pulses to at least some of the nozzles during a print job.
[0308] Optionally, the drive circuitry sends the de-clog pulses between pages of the print job.
[0309] In another aspect the present invention provides an inkjet printer further comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0310] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0311] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0312] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0313] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0314] Optionally, the pulse profile for each temperature zone differs in its duration.
[0315] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0316] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0317] Optionally, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0318] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0319] Optionally, the array of nozzles and the drive circuitry is fabricated on a printhead IC, the printhead IC being mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0320] In another aspect the present invention provides a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0321] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0322] Optionally, the drive circuitry extracts a clock signal from the print data transmission from the PEC.
[0323] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0324] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0325] According to a thirteenth aspect, the present invention provides a printhead IC for an inkjet printer, the inkjet printer having a PEC for sending print data to the printhead IC, the printhead IC comprising:
[0326] an array of nozzles for ejecting drops of printing fluid onto a media substrate; and,
[0327] drive circuitry for driving the array of nozzles, the drive circuitry being configured to extract a clock signal from the data transmission from the PEC.
[0328] By incorporating a clocking signal into the print data signal, the number of connections between the PEC and the printhead IC's. This is particularly beneficial if the pagewidth printhead is provided as a replaceable cartridge as the electrical interface that the cartridge mates with upon insertion has less contacts and therefore easier to install. Giving all the printhead IC's a write address and daisy-chaining the IC's together via their data outputs, allows the PEC to have a single data in line and a single data out line. In this case the electrical interface only has two contacts.
[0329] By initializing the printhead IC's in response to power up, the PEC/printhead IC's interface does not need a separate reset line connected to each of the IC's. In fact, the PEC can have as little as two electrical connections. There is no need to initialize the printhead IC's using. A ‘data in’ from the PEC to the printhead IC's and a ‘data out’ line from the printhead IC's back to the PEC are the only connections required if the print data is sent via a self clocking data signal. If the data in signal is not self clocking, it will need to have a clock line through the PEC/printhead IC interface.
[0330] Optionally, the data transmission is a digital signal that has a rising edge at every clock period.
[0331] Optionally, the drive circuitry determines a data bit from every clock period by the position of the falling edge during that period.
[0332] In another aspect the present invention provides a printhead IC linked with other like printhead IC's to form a pagewidth printhead, wherein the data transmission is multi-dropped to all the printhead IC's and each printhead IC has a unique write address provided by the PEC.
[0333] Optionally, the interface between the printhead and the PEC has only two connections.
[0334] In another aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0335] Optionally, each of the plurality of temperature sensors is activated sequentially for a period of time during the print job.
[0336] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0337] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0338] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0339] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0340] Optionally, the pulse profile for each temperature zone differs in its duration.
[0341] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0342] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0343] In another aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0344] In another aspect the present invention provides a printhead IC further comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0345] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0346] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0347] Optionally, the drive circuitry resets itself to a known initial state in response to receiving power from a power source after a period of not receiving power from the power source.
[0348] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0349] According to a fourteenth aspect, the present invention provides a printhead IC for an inkjet printer, the inkjet printer having a PEC for sending print data to the printhead IC, the printhead IC comprising:
[0350] an array of nozzles for ejecting drops of printing fluid onto a media substrate; and,
[0351] drive circuitry for driving the array of nozzles, the drive circuitry being configured for connection to a power source in the printer; wherein,
[0352] the drive circuitry being configured to reset itself to a known initial state in response to receiving power from the power source after a period of not receiving power from the power source.
[0353] By initializing the printhead IC's in response to power up, the PEC/printhead IC's interface does not need a separate reset line connected to each of the IC's. In fact, the PEC can have as little as two electrical connections. There is no need to initialize the printhead IC's using. A ‘data in’ from the PEC to the printhead IC's and a ‘data out’ line from the printhead IC's back to the PEC are the only connections required if the print data is sent via a self clocking data signal. If the data in signal is not self clocking, it will need to have a clock line through the PEC/printhead IC interface.
[0354] Optionally, the drive circuitry is configured to extract a clock signal from the data transmission from the PEC.
[0355] Optionally, the data transmission is a digital signal that has a rising edge at every clock period.
[0356] Optionally, the drive circuitry determines a data bit from every clock period by the position of the falling edge during that period.
[0357] In another aspect the present invention provides a printhead IC linked with other like printhead IC's to form a pagewidth printhead, wherein the data transmission is multi-dropped to all the printhead IC's and each printhead IC has a unique write address provided by the PEC.
[0358] In another aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0359] Optionally, each of the plurality of temperature sensors is activated sequentially for a period of time during the print job.
[0360] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0361] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0362] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0363] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0364] Optionally, the pulse profile for each temperature zone differs in its duration.
[0365] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0366] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0367] In another aspect the present invention provides a printhead IC mounted to a pagewidth printhead with a plurality of like printhead IC's, wherein all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0368] In another aspect the present invention provides a printhead IC comprising open actuator test circuitry for selectively disabling the actuators when they receive a drive signal while comparing the resistance of the resistive heater to a predetermined threshold to assess whether the actuator is defective.
[0369] Optionally, during use feedback from the open actuator test circuitry is used to adjust the print data subsequently received by the drive circuitry.
[0370] Optionally, the drive circuitry is configured to operate in two modes, a printing mode in which the drive pulses it generates are printing pulses, and a maintenance mode in which the drive pulses are de-clog pulses, such that, the de-clog pulse has a longer duration than the printing pulse.
[0371] Optionally, the interface between the printhead and the PEC has only two connections.
[0372] Optionally, the drive circuitry is configured to receive the print data in any one of a plurality of different data transmission protocols.
[0373] According to a fifteenth aspect, the present invention provides an inkjet printer comprising:
[0374] a pagewidth printhead with a plurality of printhead IC's, each having an array of nozzles for ejecting drops of printing fluid onto a media substrate, and associated drive circuitry for driving the array of nozzles;
[0375] a print engine controller for sending print data to the printhead IC's;
[0376] an interface for electrical communication between the print engine controller and the printhead IC's; wherein,
[0377] all the printhead IC's have a common initial address with one exception, the exception having a different address such that the print engine controller sends a first instruction to any printhead IC's having the different address, the first broadcast instruction instructing the printhead IC having the different address to change its address to a first unique address, the printhead IC's being connected to each other such that once the exception has changed its address to the first unique address, it causes one of the printhead IC's having a common address to change its address to the different address, so that when the print engine controller sends a second broadcast instruction to the different address, the printhead IC with the different address changes its address to a second unique address as well as causing one of the remaining printhead IC's having the common address to change to a different address, the process repeating until the print engine controller assigns the printhead IC's with mutually unique addresses.
[0378] Using this process, there only needs to be two electrical connections between the print engine controller and all the printhead IC's. A ‘data in’ from the PEC to the printhead IC's and a ‘data out’ line from the printhead IC's back to the PEC.
[0379] According to a second aspect, the present invention provides a printhead cartridge for an inkjet printer having a PEC for sending print data to the printhead cartridge, the printhead cartridge comprising:
[0380] a plurality of printhead IC's, each having an array of nozzles for ejecting drops of printing fluid onto a media substrate, the printhead IC's having a common initial address with one exception that has a different address;
[0381] write address circuitry for setting the exception to the different address and providing connections between the printhead IC's so that each has its address changed from the initial address to the different address when its adjacent printhead IC has its write address changed by the PEC; and,
[0382] an electrical interface for establishing two electrical connections with the PEC.
[0383] Optionally, the print data signal from the PEC is multi-dropped to the printhead IC's using the unique write addresses.
[0384] Optionally, the print data signal is self clocking.
[0385] Optionally, the drive circuitry is configured to extract a clock signal from the data transmission from the PEC.
[0386] Optionally, the data transmission is a digital signal that has a rising edge at every clock period.
[0387] Optionally, the drive circuitry determines a data bit from every clock period by the position of the falling edge during that period.
[0388] Optionally, the interface between the printhead and the PEC has only two connections.
[0389] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0390] Optionally, the pulse profile for each temperature zone differs in its duration.
[0391] Optionally, the drive circuitry sets the pulse duration to zero if the temperature sensor indicates that region is operating at a temperature above the highest of the temperature thresholds.
[0392] Optionally, the array is arranged into rows and columns of nozzles and each of the regions are a plurality of adjacent columns, such that the drive circuitry is configured to fire the nozzles one row at a time.
[0393] Optionally, the drive circuitry enables the nozzles in the row to fire in a predetermined firing sequence.
[0394] Optionally, the drive circuitry sets the duration of the pulse profile to a sub ejection value for any of the nozzles in the row that are not to eject a drop during that firing sequence.
[0395] In another aspect the present invention provides a printhead IC further comprising a plurality of temperature sensors positioned along the array of nozzles such that the drive circuitry adjusts the drive pulses in response to the temperature sensor outputs.
[0396] Optionally, each of the plurality of temperature sensors is activated sequentially for a period of time during the print job.
[0397] Optionally, the plurality of temperatures sensors are divided into two or more groups, each group being activated for a sensing period in accordance with a predetermined repeating sequence for the duration of a print job.
[0398] Optionally, each of the plurality of temperature sensors, is configured to sense the temperature a corresponding region of the array such that the drive pulse for the nozzles in one region can differs from the drive pulse for the nozzles in another region.
[0399] Optionally, every second temperature sensor in the plurality of temperature sensors is de-activated such that the drive circuitry adjusts the drive pulse profile for the region corresponding to each activated temperature sensor and applies the same adjustment to the adjacent region where the temperature sensor is de-activated.
[0400] Optionally, the drive circuitry is programmed with a series of temperature thresholds defining a set of temperature zones, each of the zones having a different pulse profile for the drive pulses sent to the nozzles in the region currently operating in that temperature zone.
[0401] Optionally, the pulse profile for each temperature zone differs in its duration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0402] Specific embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which:
[0403] FIG. 1 is a schematic representation of the linking printhead IC construction;
[0404] FIG. 2 is a schematic representation of the unit cell;
[0405] FIG. 3 shows the configuration of the nozzle array on a printhead IC;
[0406] FIG. 4 is a schematic representation of the column and row positioning of the nozzles in the array;
[0407] FIG. 5A is a schematic representation of the non-distorted array of nozzles;
[0408] FIG. 5B is a schematic representation of the distortion of the array for continuity with adjacent printhead IC's;
[0409] FIG. 5C is an enlarged view of the sloped section of the array with the ink supply channels overlaid;
[0410] FIG. 6A shows the prior art configuration of a linking printhead IC with drop triangle;
[0411] FIG. 6B shows the ink supply channels corresponding to the nozzle array shown in FIG. 6A ;
[0412] FIG. 7 is a schematic representation of the printhead connection to SoPEC;
[0413] FIG. 8 is a schematic representation of the printhead connection to MoPEC;
[0414] FIG. 9 show self clocking data signals for a ‘1’ bit and a ‘0’ bit;
[0415] FIG. 10 shows a sketch of the eight TCPG regions across an Udon IC;
[0416] FIG. 11 is a sketch of the two nozzle rows firing in sequences defined by different span and shifts;
[0417] FIG. 12 is a schematic representation of the firing sequence of a nozzle row segment with a span of five and a shift of three;
[0418] FIG. 13A the current drawn over one row time for each TCPG region and the total row during a uniformly initiated region firing sequence;
[0419] FIG. 13B is the current drawn over one row time for each TCPG region and the total row during a delayed region firing sequence;
[0420] FIG. 14 is the dot data loading and row firing sequence for a ten row Udon IC;
[0421] FIG. 15 shows the drop triangle and sloping segment of a nozzle row together with the relevant printing delay for the dot data at the ‘dropped’ nozzles;
[0422] FIG. 16 shows de-clog pulse train;
[0423] FIG. 17A is the circuitry for the Open Actuator Test in a unit cell with p-type drive FET; and,
[0424] FIG. 17B is the circuitry for the Open Actuator Test in a unit cell with n-type drive FET.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0425] The Applicant has developed a range of printhead devices that use a series of printhead integrated circuits (ICs) that link together to form a pagewidth printhead. In this way, the printhead IC's can be assembled into printheads used in applications ranging from wide format printing to cameras and cellphones with inbuilt printers. One of the more recent printhead IC's developed by the Applicant is referred to internally as wide range of printing applications. The Applicant refers to these printhead IC's as ‘Udon’ and the various aspects of the invention will be described with particular reference to these printhead IC's. However, it will be appreciated that this is purely for the purposes of illustration and in no way limiting to the scope and application of the invention.
Overview
[0426] The Udon printhead IC is designed to work with other Udon ICs to make a linking printhead. The Applicant has developed a range of linking printheads in which a series of the printhead IC's are mounted end-to-end on a support member to form a pagewidth printhead. The support member mounts the printhead IC's in the printer and also distributes ink to the individual IC's. An example of this type of printhead is described in U.S. Ser. No. 11/293,820, the disclosure of which is incorporated herein by cross reference.
[0427] It will be appreciated that any reference to the term ‘ink’ is to be interpreted as any printing fluid unless it is clear from the context that it is only a colorant for imaging print media. The printhead IC's can equally eject invisible inks, adhesives, medicaments or other functionalized fluids.
[0428] FIG. 1 shows a sketch of a pagewidth printhead 10 with the series of Udon printhead ICs 12 mounted to a support member 14 . The angled sides 16 allow the nozzles from one of the IC's 12 overlap with those of an adjacent IC in the paper feed direction 18 . Overlapping the nozzles in each IC 12 provides continuous printing across the junction between two IC's. This avoids any ‘banding’ in the resulting print. Linking individual printhead IC's in this manner allows printheads of any desired length to be made by simply using different numbers of IC's.
[0429] The printhead IC's 12 are integrated CMOS and MEMS ‘chips’. FIG. 3 shows the configuration of MEMS nozzles 20 on the ink ejection side of the printhead IC 12 . The nozzles 20 are arranged into rows 26 and columns 24 to form a parallelogram array 22 with ‘kinked’ or inclined portion 28 . The columns 24 are not aligned with the paper feed direction 18 because the sides of the array 22 are angled approximately 45° for the purposes of linking with adjacent IC's. The columns 24 follow this incline. The rows 26 are perpendicular to the paper feed direction except for a sloped section 28 inclined towards a ‘drop triangle’ 30 which has the nozzles 20 that overlap the adjacent printhead IC. This is discussed in more detail below.
[0430] FIG. 2 shows the elements of a single MEMS nozzle device 20 or ‘unit cell’. The construction of the unit cell 20 is discussed in detail in U.S. Ser. No. 11/246,687, the contents of which is incorporated herein by cross reference. Briefly, FIG. 2 shows the unit cell as if the nozzle plate (the outer surface of the printhead) were transparent to expose the interior features. The nozzle 32 is the ejection aperture through which the ink is ejected. The heater 34 is positioned in the nozzle chamber 36 to generate a vapour bubble that ejects a drop of ink through the nozzle 32 . The U-shaped sidewall 38 defines the edges of the chamber 36 . Ink enters the chamber 36 through the inlet 42 which has two rows of column features 44 that baffle pressure pulses in the ink to stop cross talk between unit cells. The CMOS layer defines the drive circuitry and has a drive FET 40 for the heater 34 and logic 46 for pulse timing and profiling. This is discussed in more detail below.
[0431] Ink is supplied to the unit cells 20 from channels in the opposite side of the wafer substrate of the printhead IC. These are described below with reference to FIG. 5C . The channels in the ‘back side’ of the printhead IC 12 are in fluid communication with the unit cells 20 on the front side via deep etched conduits (not shown) through the CMOS layer.
[0432] Separate linking printhead ICs 12 are bonded to the support member 14 so that there are no printed artifacts across the join between neighbouring printhead IC's. Each IC 12 contains ten rows 26 of nozzles 32 . As shown in FIG. 4 , there are two adjacent rows 26 for each color to allow up to five separate types of ink. Each pair of rows 26 shares a common ink supply channel in the back side of the wafer substrate.
[0433] There are 640 nozzles per row and 2×640=1280 nozzles per color channel, which equates to 5×1280=6400 nozzles per IC 12 . An A4/Letter width printhead requires a series of eleven printhead IC's (see for example FIG. 1 ), making the total nozzle count for the assembled printhead 11×6400=70 400 nozzles.
Color and Nozzle Arrangement
[0434] At 1600 dpi, the distance between printed dots needs to be 15.875 m. This is referred to as the dot pitch (DP). The unit cell 20 has a rectangular footprint that is 2 DP wide by 5 DP long. To achieve 1600 dpi per color, the rows 26 are offset from each other relative to the feed direction 18 of the paper 48 as best shown in FIG. 4 . FIG. 5A shows the parallelogram that the nozzle forms by offsetting each subsequent row 26 by 5 DP.
Linking Nozzle Arrangement
[0435] The parallelogram 50 does not allow the array 22 to link with those of adjacent printhead IC's. To maintain a constant dot pitch between the edge nozzles of one printhead IC and the opposing edge nozzles of the adjacent IC, the parallelogram 50 needs to be slightly distorted. FIG. 5B shows the distortion used by the Udon design. A portion 30 of the array 22 is displaced or ‘dropped’ relative to the rest of the array with respect to the paper feed direction 18 . For convenience, the Applicant refers to this portion as the drop triangle 30 . The unit cells 20 on the outer edge of the drop triangle 30 are directly adjacent the unit cells 20 at the edge of the adjacent printhead IC 11 in terms of their dot pitch. In this way, the separate nozzle arrays link together as if they were a single continuous array.
[0436] The ‘drop’ of the drop triangle 30 is 10 DP. Dots printed by the nozzles in the triangle 30 are delayed by ten ‘line times’ (the line time is the time taken to print one line from the printhead IC, that is fire all ten rows in accordance with the print data at that point in the print job) to match the triangle offset. There is a transition zone 28 between the drop triangle 30 and the rest of the array 22 . In this zone the rows 26 ‘droop’ towards the drop triangle 30 . Nine pairs of unit cells 20 sequentially drop by one line time (1 DP, 1 row time) at a time to gradually bridge the gap between dropped and normal nozzles.
[0437] The droop zone is purely for linking and not necessary from a printing point of view. As shown in FIG. 6A , the rows 26 could simply terminate 10 DP above the corresponding row in the drop triangle 30 . However, this creates a sharp corner in the ink supply channels 50 in the back of the IC 12 (see FIG. 6B ). The sharp change of direction in the ink flow is problematic because outgassing bubbles can become lodged and difficult to remove from stagnation areas 54 at the corners 52 . FIG. 5C shows the configuration of the ink supply channels 50 in the back of an Udon printhead IC 12 . It can be seen that the droop zone 28 keeps the ink supply channels 50 less angled and therefore free of flow stagnation areas.
[0000] Compatibility with Different Print Engine Controllers
[0438] The Udon printhead IC, can operate in different modes depending on the print engine controller (PEC) from which it is receiving its print data. Specifically, Udon runs in two distinct modes SoPEC mode and MoPEC mode. SoPEC is the PEC that the Applicant uses in its SOHO (small office, home office) printers, and MoPEC is the PEC used in its mobile telecommunications (e.g. cell phone or PDA) printers. Udon does not use any type of adaptor or intermediate interface to connect to differing PEC's. Instead, Udon determines the correct operating mode (SoPEC or MoPEC) when it powers up. In each mode, the contacts on each of the printhead IC's assume different functions.
SoPEC Mode Connection
[0439] FIG. 7 is a schematic representation of the connection of the Udon IC's 12 to a SoPEC 56 .
[0440] Each of the printhead IC's 12 has a clock input 60 , a data input 58 , a reset pin 62 and a data out pin 64 . The clock and data inputs are each 2 LVDS (low voltage differential signalling) receivers with no termination. The reset pin 62 is a 3.3V Schmitt trigger that puts all control registers into a known state and disables printing. Nozzle firing is disabled combinatorially and three consecutive clocked samples are required to reset the registers. The data output pin 64 is a general purpose output but is usually used to read register values back from the printhead IC 12 to the SoPEC 56 . The interface between SoPEC 56 and the printhead 10 has six connections.
MoPEC Mode Connection
[0441] FIG. 8 shows the connection between a MoPEC 66 and the printhead IC's 12 of a printhead 10 installed in a mobile device. Some of the same connection pins are used when the IC operates in the MoPEC mode. However, as the MoPEC printheads 10 will be physically smaller (only three chips wide for printing onto business card sized media) and more frequently replaced by the user, it is necessary to simplify the interface between the MoPEC and the printhead as much as possible. This reduces the scope for incorrect installation and enhances the intuitive usability of the mobile device.
[0442] The address carry in (ACI) 70 is the positive pin of the LVDS pair of clock input 60 in the SoPEC mode. The first printhead IC 12 in the series has the ACI 70 set to ground 68 for addressing purposes described further below. The negative pin 60 is grounded to hold it to ‘0’ voltage. The data out pin 64 connects directly to the ACI 70 of the adjacent printhead IC 12 . All the IC's 12 are daisy-chained together in this manner with the last printhead IC 12 in the series having the data out 64 connected back to the MoPEC 66 .
[0443] In MoPEC mode, the reset pin 62 remains unconnected and the negative pin 72 of the data LVDS pair is grounded. The data and clock are inputted through a single connection using the self-clocking data signal discussed below. The daisy-chained connection of the IC's 12 and the self clocking data input 58 reduce the number of connections between MoPEC and the printhead to just two. This simplifies the printhead cartridge replacement process for the user and reduces the chance of incorrect installation.
Combined Clock and Data
[0444] The combined clock and data 58 is a pulse width modulated signal as shown in FIG. 9 . The signal 74 shows one clock period and a ‘0’ bit and the signal 76 shows one clock period and a ‘1’ bit. The Udon IC's 12 (when in MoPEC mode) takes its clock from every rising edge 78 as the signal switches from low to high (0 to 1). Accordingly, the signal has a rising edge 78 at every period. A ‘0’ bit drops the signal back to ‘0 ’ at ⅓ of the clock period. A ‘1’ bit drops the signal to ‘0’ at ⅔ of the clock period. The IC looks to the state of the signal at the mid point 80 of the period to read the ‘0’ or the ‘1’ bit.
External Printhead IC Addressing
[0445] Each of the printhead IC's 12 are given a write address when connected to the MoPEC 66 . To do this using a two wire connection between the PEC and the printhead requires an iterative process of broadcast addressing to each device individually. Udon achieves this by daisy-chaining the data output or one IC to the address carry in of the next IC. The default or reset value at the data output 64 is high or ‘1’. Therefore every printhead IC 12 has a ‘1’ address except the first printhead IC 12 which has its address pulled to ‘0’ by its connection to ground 68 . To give the IC's 12 unique write addresses, the MoPEC 66 sends a broadcast command to all devices with a ‘0’ address. In response to the broadcast command, the only IC with a ‘0’ address, re-writes its write address to a unique address specified by MoPEC and sets its data out 64 to ‘0’. That in turn pulls the ACI 70 of the second IC 12 in the series to ‘0’ so that when MoPEC again sends a broadcast command to write address ‘0’ so that the second IC, and only the second IC, rewrites its address to a new and unique address, as well as setting its data output to ‘0’.
[0446] The process repeats until all the printhead IC's 12 have mutually unique write addresses and the last IC sends a ‘0’ back to MoPEC 66 . Using this system for addressing the IC's at start up, the interface need only have a connection for a combined data and clock ‘multi-dropped’ (connected in parallel) to all devices and a data out from the IC's back to MoPEC. As discussed above, a simplified electrical interface between the PEC and printhead cartridge enhances the ease and convenience of cartridge replacement.
Power On Reset
[0447] Udon printhead IC's 12 have a power on reset (POR) circuit. The ability to self initialize to a known state allows the printhead IC to operate in the MoPEC mode with only two contacts at the PEC/printhead 10 interface.
[0448] The POR circuit is implemented as a bidirectional reset pin 62 (see FIG. 7 ). The POR circuit always drives out the reset pin 62 , and the IC listens to the reset pin input side. This allows SoPEC 56 to overdrive reset when required.
PEC Interface Type Detection
[0449] On power up, the Udon printhead IC 12 switches from mode to mode and suppresses fire commands until it determines the type of PEC to which it is connected. Once it selects the correct operating mode for the PEC, it will not try to align with another PEC type again until a software reset or power down/power up cycle.
[0450] An Udon printhead IC 12 can be in three interface modes:
SoPEC mode, where both clock and data 58 are LVDS (low voltage differential signalling) contacts pairs (see FIGS. 7 and 8 ); MoPEC single-ended mode, where clock and data are combined 58 and single ended (see FIG. 8 ) because the data is pulse width modulated along the clock signal; and, MoPEC LVDS mode, where the clock 60 is single ended and data 58 is LVDS (this mode can be used if there are EMI issues).
[0454] Udon spends sufficient time in each state to align, then moves on in order if alignment is not achieved.
Multi-Stage Print Data Loading
[0455] In previous printhead IC designs, each unit cell had a shift register for the print data. Print data for the entire nozzle array was loaded and then, after the fire command from the PEC, the nozzles are fired in a predetermined sequence for that line of print. The shift register occupies valuable space in the unit cell which could be better used for a bigger, more powerful drive FET. A more powerful drive FET can provide the actuator (thermal or thermal bend actuator) with a drive pulse of sufficient energy (about 200 nJ) in a shorter time.
[0456] A bigger more powerful FET has many benefits, particularly for thermally actuated printheads. Less power is converted to wasteful heat in the FET itself, and more power is delivered to the heater. Increasing the power delivered to the heater causes the heater surface to reach the ink nucleation temperature more quickly, allowing a shorter drive pulse. The reduced drive pulse allows less time for heat diffusion from the heater into regions surrounding the heater, so the total energy required to reach the nucleation temperature is reduced. A shorter drive pulse duration also provides more scope to sequence to the nozzle firings within a single row time (the time to fire a row of nozzles).
[0457] Moving the print data shift registers out of the unit cells makes room for bigger drive FETs. However, it substantially increases the wafer area needed for the IC. The nozzle array would need an adjacent shift register array. The connections between each register and its corresponding nozzle would be relatively long contributing to greater resistive losses. This is also detrimental to efficiency.
[0458] As an effective compromise, the Udon printhead IC stages the loading and firing of the print data from the nozzle array. Print data for a first portion of the nozzle array is loaded to registers outside the array of nozzles. The PEC sends a fire command after the registers are loaded. The registers send the data to the corresponding nozzles within the first portion where they fire in accordance to the fire sequence (discussed below). While the nozzles in the first portion fire, the registers are loaded with the print data for the next portion of the array. This system removes the register from the unit cell to make way for a larger, more powerful drive FET. However, as there are only enough registers for the nozzles in a portion of the array, the resistive losses in the connection between register and nozzle is not excessive.
[0459] The drive logic on the IC 12 sends the print data to the array row by row. The nozzle array has rows of 640 nozzles in 10 rows. Adjacent to the array, 640 registers store the data for one row. The data is sent to the registers from the PEC in a predetermined row firing sequence. Previously, when the data for the entire array was loaded at once, the PEC could simply send the data for each row sequentially—row 0 to row 9 . However, with each row fired as soon as its data is loaded, the PEC needs to align with Udon's row firing sequence.
[0460] Udon's normal operating steps are described as follows:
1. Program registers to control the firing sequence and parameters. 2. Load data into the registers for a single row of the printhead. 3. Send a fire command, which latches the loaded data in the corresponding nozzles, and begins a fire sequence. 4. Load data for the next row while the fire sequence is in progress. 5. Repeat for all rows in the line. 6. Repeat for all lines on the page.
Temperature Controlled Profile Generator (TCPG) Regions
[0467] Ink viscosity is dependent on the ink temperature. Changes in the viscosity can alter the drop ejection characteristics of a nozzle. Along the length of a pagewidth printhead, the temperature may vary significantly. These variations in temperature and therefore drop ejection characteristics leave artefacts in the print. To compensate for temperature variations, each Udon printhead IC has a series of temperature sensors which output to the on-chip drive logic. This allows the drive pulse to be conditioned in accordance with the current ink temperature at that point along the printhead and thereby eliminate large differences in drop ejection characteristics.
[0468] Referring to FIG. 10 , each Udon IC 12 has eight temperature sensors 74 positioned along the array 22 . Each sensor 74 senses the temperature in the adjacent region of nozzles, referred to as Temperature Controlled Profile Generator regions, or TCPG regions 76 . A TCPG region 76 is a ‘vertical’ band down the IC 12 that shares temperature and firing data (see the row firing sequence described later). Pulse width is set for each color on the basis of region, and temperature within that region.
Periodic Sensor Activation
[0469] The sensors 74 allow temperature detection between 0° C. and 70° C. with a typical accuracy after calibration of 2° C. Individual temperature sensors may be switched off and a region may use the temperature sensor 74 of an adjoining region 78 . This will save power with minimal effect on the correct conditioning of the drive pulse as the sensors will sense heat generated in regions outside their own because of conduction. If the steady state operating temperatures shown little or no variation along the IC, then it may be appropriate to turn off all the sensors except one, or indeed turn off all the sensors and not use any temperature compensation. Reducing the number of sensors operating at once not only reduces power consumption, but reduces the noise in other circuits in the IC.
Temperature Categories
[0470] Each TCPG region 76 has separate registers for each of the five inks. The temperature of the ink is categorised into four temperature ranges defined by three predetermined temperature thresholds. These thresholds are provided by the PEC. The profile generator within the Udon logic adjust the profile of the drive pulse to suit the current temperature category.
Sub-Ejection Pulses
[0471] Heat dissipates into the ink as the heater temperature rises to the bubble nucleation temperature. Because of this, the temperature of the ink in a nozzle will depend on how frequently it is being fired at that stage of the print job. A pagewidth printhead has a large array of nozzles and at any given time during the print job, a portion of the nozzles will not be ejecting ink. Heat dissipates into regions of the chip surrounding nozzles that are firing, increasing the temperature of those regions relative to that of non-firing regions. As a result, the ink in non-ejecting nozzles will be cooler than that in nozzles firing a series of drops.
[0472] The Udon IC 12 can send non-firing nozzles ‘sub-ejection’ pulses during periods of inactivity to keep the ink temperature the same as that of the nozzles that are being fired frequently. A sub-ejection pulse is not enough to eject a drop of ink, but heat dissipates into ink. The amount of heat is approximately the same as the heat that conducts into the ink prior to bubble nucleation in the firing nozzles. As a result, the temperature in all the nozzles is kept relatively uniform. This helps to keep viscosity and drop ejection characteristics constant. The sub-ejection pulse reduces its energy by shortening its duration.
Drive Pulse Profiling
[0473] Actively changing the profile of the drive pulse offers many benefits including:
optimum firing pulse for varying inks and temperatures warming a region before it fires shutting down or just slowing down an IC that gets too hot (Udon provides the information, PEC controls speed) adjusting for voltage drop caused by distance (extra resistance) from the power source reducing the energy input to the chip, as warm ink requires less energy to eject than cold ink
[0479] The pulse profile can vary according to temperature and ink type. The firing pulses generated by the TCPG regions are stored in large registers that contain values for each of five inks in each of four temperature ranges, plus universal ink and region values, and threshold values. These values must be supplied to the Udon and may be stored in and/or delivered by the QA chip on the ink cartridge (see RRC001US incorporated herein by reference), the PEC, or elsewhere.
Controlling the Pulse Width
[0480] It is convenient to adjust the firing pulses by varying the pulse duration instead of voltage or current. The voltage is externally applied. Varying the current would involve resistive losses. In contrast, the pulse timing is completely programmable.
[0481] Ideal ink ejection firing pulses for Udon are typically between 0.4 s and 1.4 s. Sub-ejection firing pulses are usually less than 0.3 s. More generally, the firing pulse is a function of several factors:
MEMs characteristics Ink characteristics Temperature FET type
[0486] The magnitude of the optimum firing pulse may vary depending on color and temperature. Udon stores the ejection pulse time for each color, in all temperature zones, in all regions.
Row Firing Sequence
[0487] If all nozzles in a row were fired simultaneously, the sudden increase in the current drawn would be too high for the printhead IC and supporting circuitry. To avoid this, the nozzles, or groups of nozzles, can be fired in staggered intervals. However, firing adjacent nozzles simultaneously, or even consecutively, can lead to drop misdirection. Firstly the droplet stalks (the thin column of ink connecting an ejected ink drop to the ink in the nozzle immediately prior to droplet separation) can cause micro flooding on the surface of the nozzle plate. The micro floods can partially occlude an adjacent nozzle and draw an ejected drop away from its intended trajectory. Secondly, the aerodynamic turbulence created by one ejected drop can influence the trajectory of a drop ejected simultaneously (or immediately after) from a neighboring nozzle. The second fired drop can be drawn into the slipstream of the first and thereby misdirected. Thirdly the fluidic cross talk between neighboring nozzles can cause drop misdirection.
[0488] Udon addresses this by dispersing the group of nozzles that fire simultaneously, and then fires nozzles from every subsequent dispersed group such that sequentially fired nozzles are spaced from each other. The nozzle firing sequence continues in this manner until all the nozzles (that are loaded with print data) in the row have fired.
[0489] To do this, each row of nozzles is divided into a number of adjacent spans and one nozzle from each span fires simultaneously. The subsequently firing nozzle from each span is spaced from the previously firing nozzle by a shift value. The shift value can not be a factor of the span number (that is, the shift and the span should be mutually prime) so nozzles at the boundary between neighbouring spans do not fired simultaneously, or consecutively.
Span
[0490] The span is the number of consecutive nozzles in the row from which only one nozzle will fire at a time. FIG. 11 shows a partial row of nozzles being fired with a span of three, and the same row segment with a span of five. For the purposes of illustration, the shift value is one. However, as discussed above, this is not an appropriate shift value in practice as the adjacent nozzles will fire consecutively. The turbulent wake from the drop fired from the first nozzle can interfere with the drop fired from the adjacent model immediately afterwards. It can also be a problem for the ink supply flow to the adjacent nozzles.
[0491] For a span of three, there are three firings before the entire row is fired.
First firing: every third nozzle in a row fires. Second firing: the nozzle to one side of the first nozzle fires. Third firing: the nozzle two across from the first nozzle fires all nozzles on this row have now fired. The nozzles in row N+2 now begin their fire cycle using the same span pattern. One third of a row's nozzles fire at any one time.
[0497] For a span of five, there are five firings before the entire row is fired and one fifth of the row's nozzles fire at any one time.
[0498] At the extremes (for Udon printhead IC's):
span=1 fires all nozzles in a row simultaneously, draws too much current and will damage the IC; span=640 fires one nozzle at a time, but may take too long to complete in the time allotted to a single row.
[0501] In any case, span only controls the maximum number of nozzles that are able to fire at any one time. Each individual nozzle still needs a 1 in its shift register to actually fire. In the examples below, we assume that the IC is printing a solid color line, so every nozzle of the color will fire. In reality, this is rarely the case.
Shift
[0502] The examples shown in FIG. 11 have a shift value of one. That is, one nozzle fires, then the next nozzle left fires, then the next, etc. As discussed above, this is impractical. FIG. 12 shows a segment of the nozzle row with a span of 5 with a span shift of 3.
First firing: column 1 fires. Second firing: the firing nozzle is 3 nozzles across at column 4 Third firing: the count has wrapped around and is back at nozzle 2 . Fourth firing: nozzle 5 fires. Fifth firing: nozzle 3 fires all 5 nozzles in the span have now fired.
[0508] To fire every nozzle in the row exactly once, the shift can not be a factor of the span, i.e. the span can not be divided by the shift (without remainder). To maximize droplet separation in time and space and still fire every nozzle exactly once per row, the closest mutual prime to the square root of the span should be chosen for span shift. For example, for a span of 27, a span shift of 5 would be appropriate.
Firing Delay
[0509] Firing all the nozzles in a row simultaneously, will draw a large amount of current that remains (approximately) constant for the duration of the row time. This still requires the power supply to step from zero current to a maximum current in a very short time. This creates a high rate of change of current drawn until the maximum value is reached. Unfortunately, a rapid increase in the current creates inductance which increases the circuit impedance. With high impedance, the drive voltage ‘sags’ until the inductance returns to normal, i.e. the current stops increasing. In printhead IC's, it is necessary to keep the actuator supply voltage within a narrow range to maintain consistent ink drop size and directionality.
[0510] As the firing pulses in each region can be varied by the TCPG, it can be used to delay the start of firing in each region across the printhead. This reduces the rate of change in current during firing. FIGS. 13A and 13B show the relationship between region firing delay and current drain. FIG. 13A shows the two extremes of power usage when printing a solid line of a color (this is the worst case for power supply because 80 dots will fire across the region).
[0511] FIG. 13A shows no firing delay between regions. Each region has 4 spans of 20 nozzles each. Each of the regions fire for the entire row time (row time is the time available for a complete row of nozzles to fire). Therefore, at any time during the row time, four nozzles from all of the eight regions are firing (drawing current). Hence the profile of the supply current is a long flat step function 78 and identical for each region. The profile for the entire row is the accumulated step function 80 of the individual profiles 78 . Theoretically the leading edge 90 of step function 80 is vertical but in fact it is very steep until it reaches the maximum current level 82 . The high rate of change in the current can cause the undesirable voltage sags.
[0512] FIG. 13B shows the current supply profiles when the regions are fired in stages. To stagger the firing of each region, the time in which the nozzles in each span can fire must be reduced. In the example shown in FIG. 13B , each span has half the row time in which to fire its nozzles. To compress the time needed for each span to fire, the number of nozzles in the span can be reduced. For example, the span in FIG. 13B is 10, so 8 nozzles (10×8=80 nozzles/region) from each span will fire simultaneously. The cumulative current drawn for eight nozzles is greater than that for the four nozzles firing per span shown in FIG. 13A . So the current drawn for each region in FIG. 13B is twice that of the regions in FIG. 13A , but the current is drawn for half the time. Region 1 is supply with current 84 at the beginning of the row time. The current supply 94 to region 2 starts after a set delay period and region 3 is similarly delayed relative to region 2 , and so on until region 8 starts its firing sequence. The delays for each region need to be timed so that region 8 starts firing at or before half the row time has elapsed.
[0513] The cumulative current supply profile 86 shows the series of 8 rapid steps in the current supply as it reaches its maximum value 88 . The maximum current 88 is greater than the maximum current 82 in the non-delayed region firing, but the rate of increase in the supply current 92 is less. This induces less impedance in the circuit so that the voltage sag is lower. In each case, the total energy used is the same for a given row time but the distribution of energy consumption is adjusted.
Normal Firing Order
[0514] As discussed above, print data is sent to the printhead IC's 12 one row at a time followed by a fire command. Previously, each individual unit cell in the nozzle array had a shift register to store the print data (a ‘1’ or ‘0’) for each nozzle, for each line time (the line time is the time taken for the printhead to print one line of print). The print data for the entire array would be loaded into the shift registers before a fire command initiated the firing sequence. By loading and firing the print data for each line in stages, a smaller number of shift registers can be positioned adjacent the array instead of within each unit cell. Removing the shift registers from the unit cell 20 allows the drive FET 40 (see FIG. 2 ) to be larger. This improves the printhead efficiency for the reasons set out below.
[0515] Thermal printhead IC's are more efficient if the vapor bubble generated by heater element is nucleated quickly. Less heat dissipates into the ink prior to bubble nucleation. Faster nucleation of the bubble reduces the time that heat can diffuse into wafer regions surrounding the heater. To get the bubble to nucleate more quickly, the electrical pulse needs to have a shorter duration while still providing the same energy to the heater (about 200 nJ). This requires the drive FET for each nozzle to increase the power of the drive pulse. However, increasing the power of the drive FET increases its size. This enlarges the wafer area occupied by the nozzle and its associated circuitry and therefore reduces the nozzle density of the printhead. Reducing the nozzle density is detrimental to print quality and compact printhead design. By removing the shift register from the unit cell, the drive FET can be more powerful without compromising nozzle density.
[0516] The Udon design writes data to the nozzle array one row at a time. However, a printhead IC that loaded and fired several rows at a time would also be achieving the similar benefits. However, it should be noted that the electrical connection between the shift register and the corresponding nozzle should be kept relatively short so as not to cause high resistive losses.
[0517] Loading and firing the print data one row at a time requires the PEC to send the data in the row order that it is printed. Previously the data for the entire nozzle array was loaded before firing so the PEC was indifferent to the row firing order chosen by the printhead IC. With Udon, the PEC will need to transmit row data in a predetermined order.
[0518] Printhead nozzles are normally fired according to the span/shift fire sequence and the delayed region start discussed above. The supply channels 50 in the back of the printhead IC 12 (see FIG. 5C ) supply ink to two adjacent rows of nozzle on the front of the IC, that is rows 0 and 1 eject the same color, rows 2 and 3 eject another color, and so on. The Udon printhead IC has ten row of nozzles, these can be designated colors CMYK, IR (infra-red ink for encoding the media with data invisible to the eye) or CMYKK. To avoid ink supply flow problems, every second row is fired in two passes, that is row 0 , row 2 , row 4 , row 6 , row 8 , then row 1 , row 3 , row 5 , and so on until all ten row are fired.
[0519] Row firings should be timed such that each row takes just under 10% of the total line time to fire. A fire command simply fires the data that is currently loaded. When operating in SoPEC mode, Udon printhead IC receives a ‘data next’ command that loads the next row of data in the predetermined order. In MoPEC mode, each row of data must be specifically addressed to its row.
[0520] Taking paper movement into account, a row time of just less than 0.1 line time, together with the 10.1 DP (dot pitch) vertical color pitch appears on paper as a 10 DP line separation. Odd and even same-color rows of nozzles, spaced 3.5 DP apart vertically and fired 0.5 line time apart results as dots on paper 5 DP apart vertically.
Fire Cycle
[0521] FIG. 14 shows the data flows and fire command sequences for a line of data. When a fire command is received in the data stream, the data in the row of shift registers transfers to a dot-latch in each of the unit cells, and a fire cycle is started to eject ink from every nozzle that has a 1 in its dot-latch. Meanwhile the data for the next row in the firing order is loaded.
Drop Triangle and Droop Section Firing Delay
[0522] Drop compensation is the compensation applied by Udon drive logic 46 (see FIG. 2 ) to the sloping region 28 and drop triangle 30 of nozzles at the left of the nozzle array 22 on each IC 12 (see FIG. 5C ). As shown in FIG. 15 , the print data to the nozzles that are displaced from the rest of the array 22 needs to be delayed by a certain number of line times. FIG. 15 shows the nozzles in one row 26 of the IC 12 . The nozzles in the drop triangle 30 are all displaced 10 dot pitches from the non-displaced nozzles in the row. The nozzles in the droop section 28 that connects the drop triangle 30 and the non-displaced nozzles have a displacement that indexes by one dot pitch every two nozzles. In the sloping droop region 28 the drive logic indexes the delay in firing the dot data correspondingly.
Nozzle Blockage Clearing
[0523] During periods of inactivity, or even between pages, and especially at higher ambient temperatures, nozzles may become blocked with more viscous or dried ink. Water can evaporate from the ink in the nozzles thereby increasing the viscosity of the ink to the point where the bubble is unable to eject the drop. The nozzle becomes clogged and inoperable.
[0524] Many printers have a printhead maintenance regime that can recover clogged nozzles and clean the exterior face of the printhead. These create a vacuum to suck the ink through the nozzle so that the less viscous ink refills the nozzle. A relatively large volume of ink is wasted by this process requiring the cartridges to be replaced more frequently.
[0525] Udon printhead IC's have a maintenance mode that can operate before or during a print job. During maintenance mode the drive logic generates a de-clog pulse for the actuators in each nozzle unless the dead nozzle map (described below) indicates that the actuator has failed. To operate during a print job, the nozzles should fire the de-clog pulse into the gap between pages without interruption to the paper.
[0526] The de-clog pulse is longer than the normal drive pulses. The bubble formed from a longer duration pulse is larger and imparts a greater impulse to the ink than a firing impulse. This gives the pulse the additional force that may be needed to eject high viscosity ink.
[0527] As a preliminary measure, the de-clog pulse can be preceded by a series of sub-ejection pulses to warm the ink and lower viscosity. FIG. 16 shows a typical de-clog pulse train with a series of short (relative to a firing pulse) sub-ejection pulses 94 followed by a single de-clog pulse 96 . The individual sub-ejection pulses 94 have insufficient energy to nucleate a bubble and therefore eject ink. However, a rapid series of them raises the ink temperature to assist the subsequent de-clog pulse 96 .
Open Actuator Testing
[0528] The Udon printhead IC 12 supports an open actuator test. The open actuator test (OAT) is used to discover whether any actuators in the nozzles array have burnt out and fractured (usually referred to as becoming ‘open’ or ‘open circuit’).
[0529] Fabrication of the MEMS nozzle structures on wafer substrates will invariably result in some defective nozzles. These ‘dead nozzles’ can be located using a wafer probe immediately after fabrication. Knowing the location of the dead nozzles, the print engine controller (PEC) can be programmed with a dead nozzle map. This is used to compensate for the dead nozzles with techniques such as nozzle redundancy (the printhead IC is has more nozzles than necessary and uses the ‘spare’ nozzles to print the dots normally assigned to the dead nozzles).
[0530] Unfortunately, nozzles also fail during the operational life of the printhead. It is not possible to locate these nozzles using a wafer probe once they have been mounted to the printhead assembly and installed in the printer. Over time, the number of dead nozzles increases and as the PEC is not aware of them, there is no attempt to compensate for them. This eventually causes visible artifacts that are detrimental to the print quality.
[0531] In thermal inkjet printheads and thermal bend inkjet printheads, the vast majority of failures are the result of the resistive heater burning out or going open circuit. Nozzles may fail to eject ink because of clogging but this is not a ‘dead nozzle’ and may be recovered through the printer maintenance regime. By determining which nozzles are dead with an on-chip test, the print engine controller can periodically update its dead nozzle map. With an accurate dead nozzles map, the PEC can use compensation techniques (e.g. nozzle redundancy) to extend the operational life of the printhead.
[0532] The Udon IC open actuator test compares the resistance of the actuator to a predetermined threshold. A high (or infinite) resistance indicates that the actuator has failed and this information is fed back to the PEC to update its dead nozzle compensation tables. It is important to note that the OAT can discover open circuit nozzles, but not clogged nozzles.
[0533] Thermal actuators and thermal bend actuator both use heater elements and the OAT can be equally applied to either. Likewise, the drive FET can be N-type or P-type. FIGS. 17A and 17B show the circuits for the OAT as applied to a single unit cell with a single heater element driven by a p-FET and an n-FET respectively.
[0534] In FIG. 17A , the drive p-FET 40 is enabled during printing whenever the ‘row enable’ (RE) 98 and ‘column enable’ (CE) 100 are both asserted (receive ‘1’s at their contacts). Enabling the drive FET 40 opens the heater element 34 to Vpos 104 to activate the unit cell. When the row enable 98 or the column enable 100 are not asserted, the bleed n-FET is enabled. The bleed n-FET 112 ensures that the voltage at the sense node 120 is pulled low when the unit cell is not activated to eliminate any electrolysis path.
[0535] When the OAT 106 is asserted, the AND gate 108 pulls the gate of the drive p-FET 40 high to disable it. Asserting the OAT 106 also pulls the gate of the sense n-FET 114 high to connect the sense output 116 to the sense node 120 . With the bleed n-FET 112 disabled the voltage at the sense node 120 will still be pulled low through the heater element 34 to ground 68 . Accordingly, the sense output 116 is low to indicate that the actuator is still operational. However, if the heater element 34 is open (failed), the voltage at the sense node 120 remains high and this pulls the sense output 116 high to indicate a dead nozzle. This is fed back to the PEC which updates the dead nozzle map and initiates measures to compensate (if possible).
[0536] The unit cell circuitry shown in FIG. 17B uses a drive n-FET 40 . In this embodiment, asserting the row enable 98 and the column enable 100 pulls the gate of the drive n-FET 40 high to enable it and allow Vpos 104 to drain to ground through the heater 34 . Again the bleed p-FET 118 is disabled whenever the row enable 98 and column enable 100 are asserted.
[0537] To initiate an actuator test, the OAT 106 is asserted, together with the row enable 98 and column enable 100 . This disables the drive n-FET 40 by pulling the gate low using NAND logic 110 . It also opens the sense n-FET 114 to connect the sense output 116 to the sense node 120 . With the heater 34 insulated from ground 68 when the drive FET 40 is disabled, the sense node 120 is pulled high and a high sense output 116 indicates a working actuator. If the heater 34 is broken, the sense node 120 is left at low voltage following the last time the drive FET 40 was enabled. Accordingly when the OAT is enabled, the sense output 116 is low and the PEC records the dead nozzle to the dead nozzle map.
[0538] It will be appreciated that the open actuator test should be performed shortly after the printhead IC has been printing. After a period of inactivity, the bleed p-FET 118 or n-FET 112 drops the sense node to low voltage. The gap in printing between pages is a convenient opportunity to perform an open actuator test.
[0539] The present invention has been described herein by way of example only. Skilled workers in this field will readily recognise many variations and modification which do not depart from the spirit and scope of the broad inventive concept. | Provided is a printhead integrated circuit for an inkjet printer that has a nozzle and a corresponding actuator for ejecting ink through the nozzle. The Printhea IC also has drive circuitry for controlling the operation of the actuator. The drive circuitry has an open actuator test circuit comprising an open actuator test input, a column enable input and a row enable input, a drive transistor operatively linking said actuator to a power supply, a bleed transistor arranged in parallel with the actuator, a sense transistor operatively linking an output of the drive transistor and inputs of the actuator and bleed transistor to a sensing node. Actuating the actuator to eject ink by enabling the column and row enable inputs, deactivates the bleed transistor and activates the drive transistor to link the actuator to the power supply. Testing the actuator involves enabling the open actuator test input to activate the sense transistor, so that the actuator is short-circuited and the sense node is pulled high if the actuator is open-circuit. | 1 |
This patent application claims benefit of U.S. Provisional Patent Application Ser. No. 60/877,202, filed on Dec. 26, 2006. The teachings of U.S. Provisional Patent Application Ser. No. 60/877,202 are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
Skin care has been practiced for thousands of years, dating back to the Ancient Egyptians. Cleopatra was known for her skin car regimen, and is said to have discovered some of the first anti-aging methods. Skin care has evolved through the years with every generation being eager to slow, prevent or reverse the aging process.
Countless skin care products are commercially available for beautification of the skin and to fight wrinkle formation. For example, U.S. Pat. No. 4,938,969 discloses a composition for reducing the depth or intensity of fine wrinkles in skin affected by intrinsic or photo-induced aging. The topical formulation described by U.S. Pat. No. 4,938,969 is comprised of ascorbic acid, tyrosine and a non-toxic zinc salt and is preferably formulated in a hydrophilic ointment or cream base. This composition is reported to be effective for the treatment of aging or photo-damaged skin and in reducing wrinkles.
The effectiveness of all skin care products is normally contingent upon delivery of the active ingredients therein through the stratum corneum and viable epidermis into the dermis layer of the skin structure. This is because the active ingredients in the skin care product cannot be effective unless they penetrate through the dead layers of skin tissue and into the dermis layer of living skin cells. This is normally a difficult proposition for water soluble active ingredients, such as ascorbic acid, because the stratum corneum is a good water barrier. The stratum corneum and viable epidermis act to protect the body by holding water therein to prevent dehydration and by keeping external water which is frequently contaminated out of the body.
SUMMARY OF THE INVENTION
The subject invention relates to a skin cream that can be used to rejuvenate skin that has been damaged by exposure to sunlight or which has simply been affected over the years by intrinsic aging. It can also be used to slow the rate of photo-induced aging to maintain beautiful skin tone and texture over the years. It inhibits the formation of wrinkles and in some cases reduces the depth of existing wrinkles or eliminates them entirely. In some cases, the skin cream of this invention also lightens age spots and other types of blemishes associated with aging.
The skin cream of this invention is non-irritating and can be used to soothe the pain of sunburns and in the treatment of red, irritated, dry, cracked or itchy skin. It can also be used in treating atopic dermatitis, psoriasis, and ichthyosis by moisturizing the skin. The skin cream of this invention is typically applied to the face, décolletage, and/or hands of a patient. However, it can be generally used anywhere on the skin of a patient's body. For instance, it can also be applied to the patient's feet, chest, back, legs, ankles, arms, and/or wrists as desired.
This invention is based upon the discovery that alkyl lactates, such as ethyl lactate, can be used to improve the penetration of active ingredients in skin care formulations deep into lower layers of the skin tissue. For instance, ethyl lactate can be included in aqueous based skin creams, such as oil in water emulsions, to deliver active ingredients deep into the skin structure. Ethyl lactate is particularly desirable for utilization in conjunction with skin cream formulations that contain water soluble active ingredients, such as ascorbic acid (Vitamin C). This is beneficial because the overall effectiveness of skin creams that utilize ascorbic acid and/or other water soluble active ingredients is contingent upon delivery of the ascorbic acid through the outer layers of the stratum corneum and viable epidermis and into the dermis layer of the skin structure.
The present invention more specifically discloses a topical formulation comprising about 1 weight percent to about 20 weight percent ascorbic acid, about 1 weight percent to about 10 weight percent of an amino acid selected from the group consisting of phenylalanine and tyrosine, about 0.5 weight percent to about 5 weight percent of a non-toxic zinc salt, about 0.01 weight percent to about 20 weight percent of an alkyl lactate, wherein the alkyl group in the alkyl lactate contains from 2 to about 12 carbon atoms, and a pharmaceutically acceptable carrier.
The subject invention further reveals a topical formulation comprising about 1 weight percent to about 20 weight percent ascorbic acid, about 1 weight percent to about 10 weight percent phenylalanine, about 0.5 weight percent to about 5 weight percent of a non-toxic zinc salt, and a pharmaceutically acceptable carrier.
The present invention also discloses a method of rejuvenating human skin affected by intrinsic aging and/or photo-induced aging, said method comprising topically applying a topical formulation to the skin, wherein the topical formulation is comprised of about 1 weight percent to about 20 weight percent ascorbic acid, about 1 weight percent to about 10 weight percent of an amino acid selected from the group consisting of phenylalanine and tyrosine, about 0.5 weight percent to about 5 weight percent of a non-toxic zinc salt, about 0.01 weight percent to about 20 weight percent of an alkyl lactate, wherein the alkyl group in the alkyl lactate contains from 2 to about 12 carbon atoms, and a pharmaceutically acceptable carrier.
The subject invention further discloses a method of rejuvenating human skin affected by intrinsic aging and/or photo-induced aging, said method comprising topically applying a topical formulation to the skin, wherein the topical formulation is comprised of about 1 weight percent to about 20 weight percent ascorbic acid, about 1 weight percent to about 10 weight percent phenylalanine, about 0.5 weight percent to about 5 weight percent of a non-toxic zinc salt, and a pharmaceutically acceptable carrier.
It is preferred for the alkyl lactate utilized in the topical formulations of this invention to be ethyl lactate with it being more preferred for the alkyl lactate to be a mixture of ethyl lactate and iso-amyl lactate. It is also preferred for the topical formulations of this invention to contain α-tocopherol, carnosic acid, idebenone, and/or palmitoyl pentapeptide.
The present invention also reveals a topical formulation comprising about 0.01 weight percent to about 5 weight percent idebenone, about 0.01 weight percent to about 20 weight percent of an alkyl lactate, wherein the alkyl group in the alkyl lactate contains from 2 to about 12 carbon atoms, and a pharmaceutically acceptable carrier.
The subject invention further discloses a topical formulation comprising (1) about 0.01 weight percent to about 2 weight percent of at least one polyphenolic antioxidant selected from the group consisting of condensed proanthocyanidins, chlorogenic acid, quinic acid, and ferulic acid, (2) about 0.01 weight percent to about 20 weight percent of an alkyl lactate, wherein the alkyl group in the alkyl lactate contains from 2 to about 12 carbon atoms, and (3) a pharmaceutically acceptable carrier.
The present invention also reveals a topical formulation comprising about 0.01 weight percent to about 5 weight percent carnosic acid, about 0.01 weight percent to about 20 weight percent of an alkyl lactate, wherein the alkyl group in the alkyl lactate contains from 2 to about 12 carbon atoms, and a pharmaceutically acceptable carrier.
DETAILED DESCRIPTION OF THE INVENTION
The topical skin cream formulations of this invention will normally contain from about 1 weight percent to about 20 weight percent ascorbic acid (Vitamin C). Higher levels of ascorbic acid can be used, but do not generally yield a better result. However, in cases where the ascorbic acid is utilized at levels of less than about 1 weight percent the improvement of treated skin in minimal. It is typically preferred for the ascorbic acid to be utilized in the topical skin cream formulation at a level which is within the range of about 5 weight percent to about 15 weight percent. It is typically more preferred for the ascorbic acid to be utilized in the topical skin cream formulation at a level which is within the range of about 8 weight percent to about 12 weight percent. For improved long term shelf stability the level of ascorbic acid will typically be limited to an amount which is within the range of 2 weight percent to 5 weight percent and preferably within the range of 3 weight percent to 4.5 weight percent.
The topical skin cream formulations of this invention will also typically contain from about 0.1 weight percent to about 5 weight percent of a non-toxic zinc salt. The skin cream formulation will preferably contain from about 0.5 weight percent to about 4 weight percent of the zinc salt and will most preferably contain from about 1 to about 3 weight percent of the zinc salt. The zinc salt will preferably be a water soluble zinc salt, such as zinc bacitracin (baciferm), zinc salicylate (zinc salt of 2-hydroxybenzoic acid), or zinc sulfate. Zinc sulfate is generally preferred for used as the zinc salt. However, zinc salicylate offers the advantage of providing antiseptic action which can be desirable for preventing the growth of bacteria in the skin cream formulation during storage and can also be beneficial in certain patients, such as patients suffering from acne.
The topical skin cream formulations of this invention will also typically contain from about 1 weight percent to about 10 weight percent of an amino acid selected from the group consisting of phenylalanine and tyrosine. It is normally preferred for the amino acid to be phenylalanine. The skin cream will generally contain from about 2 weight percent to about 8 weight percent of the amino acid and will preferably contain from about 2.5 weight percent to about 4 weight percent of the amino acid.
It is important for the topical skin cream formulations of this invention to contain an alkyl lactate for the active ingredients, particularly the ascorbic acid, to better penetrate through the stratum corneum and the viable epidermis to gain entry into the dermis. This is because the active ingredients of the skin cream can only serve their intended purpose after reaching the living dermis layer of the skin. The alkyl lactate will normally be present in the skin cream formulation at a level which is within the range of about 0.01 weight percent to about 20 weight percent. The alkyl lactate will more typically be present in the skin cream formulation at a level which is within the range of about 0.1 weight percent to about 15 weight percent. The alkyl lactate will preferably be present in the skin cream formulation at a level which is within the range of about 0.2 weight percent to about 1 weight percent and will more preferably be present at a level which is within the range of about 0.2 weight percent to about 0.5 weight percent.
The alkyl lactate utilized will typically have an alkyl group that contains from 2 to about 12 carbon atoms and will accordingly be of the structural formula:
wherein R represents an straight chained or a branched alkyl group that contains from 2 to 12 carbon atoms. It is preferred for the alkyl group to contain from 2 to about 6 carbon atoms. Ethyl lactate is highly preferred because it is highly dispersible in aqueous solutions. Ethyl lactate is of the structural formula:
and is a colorless liquid having a strong odor. It is preferred to utilize a mixture of ethyl lactate with a higher molecular weight alkyl lactate in cases where oil soluble active ingredients, such as α-tocopherol are included in the topical skin cream formulation. Isoamyl lactate is preferred for utilization in such mixtures. Isoamyl lactate is of the structural formula:
and is a colorless liquid having a pleasant mild odor.
In cases where a mixture of ethyl lactate and isoamyl lactate are utilized in the skin cream formulation the weight ratio of ethyl lactate to isoamyl lactate will typically be within the range of about 1:10 to about 20:1. The weight ratio of ethyl lactate to isoamyl lactate will more typically be within the range of about 1:5 to about 10:1. Such mixtures of ethyl lactate and isoamyl lactate will preferably contain from about 30 weight percent to 70 weight percent ethyl lactate and from about 30 weight percent to about 70 weight percent isoamyl lactate. Such mixtures of ethyl lactate and isoamyl lactate will more preferably contain from about 40 weight percent to 60 weight percent ethyl lactate and from about 40 weight percent to about 60 weight percent isoamyl lactate. Such mixtures of ethyl lactate and isoamyl lactate will most preferably contain from about 45 weight percent to 55 weight percent ethyl lactate and from about 45 weight percent to about 55 weight percent isoamyl lactate.
It is highly desirable for the skin cream formulations of this invention to contain α-tocopherol (Vitamin E) for a number of important reasons. For instance, α-tocopherol is a powerful antioxidant that can serve to protect the skin cells of a patient being treated from photo-induced damage as well as other causes of oxidative aging. The α-tocopherol also helps to preserve the skin cream composition from oxidation during storage. This is particularly important in compositions that contain high levels of ascorbic acid, such as compositions that contain over 3 weight percent and particularly 5 weight percent ascorbic acid. It was also unexpectedly found that α-tocopherol helps to mask the odor of ethyl lactate in the skin cream compositions of this invention. This makes the skin cream much more pleasant for patients to use and is of particular importance in cases where the patient will used the skin cream formulation over a prolonged period of time.
It was found that α-tocopherol helps to prevent the skin cream compositions of this invention from yellowing due to oxidation of the ascorbic acid therein. However, it was unexpectedly found that the α-tocopherol must be present at a specific level to protect ascorbic acid from oxidation and to accordingly prevent the skin cream formulation from yellowing. More specifically, in cases where α-tocopherol is present at levels of less than about 5 weight percent the skin cream is prone of yellowing and in cases where the α-tocopherol is present at levels of greater than about 25 weight percent the skin cream is also prone to yellowing. In such cases, additional antioxidants, such as butylated hydroxytoluene (BHT) should be included in the formulation to prevent oxidation of the ascorbic acid. However, in cases where the α-tocopherol is present at a level which is within the range of about 10 weight percent to about 20 weight percent the skin cream formulations of this invention the ascorbic acid is resistant of oxidative degradation. For this reason, it is preferred to include α-tocopherol at a level which is within the range of about 5 weight percent to about 25 weight percent with it being more preferred to include the α-tocopherol at a level which is within the range of about 10 weight percent to about 20 weight percent. In cases where other agents are used to protect the ascorbic acid from oxidation, α-tocopherol can be beneficially employed in the skin cream at levels which are within the range of 1 weight percent to 30 weight percent. In such cases the α-tocopherol will typically be employed in the skin cream at levels which are within the range of 2 weight percent to 8 weight percent and preferably within the range of 3 weight percent to 5 weight percent. In such formulations it is frequently desirable to include about 0.1 weight percent to about 5 weight percent BHT to further inhibit yellowing. Such formulations will typically contain from about 0.5 weight percent to 2 weight percent BHT and will more typically contain from 0.8 weight percent to 1.2 weight percent BHT.
Camosic acid can be included in the skin cream formulations of this invention to provide a higher level of protection against photo-induced and other types of oxidative attack on skin cells. The carnosic acid will typically be included in the skin cream formulation at a level which is within the range of 0.01 weight percent to 1.5 weight percent. It is normally preferred to include the carnosic acid at a level which is within the range of 0.05 weight percent to 1 weight percent with levels of 0.1 weight percent to 0.8 weight percent being most preferred. The carnosic acid is naturally found in Libiatae plants, such as rosemary, marjoram, and sage.
U.S. Pat. No. 5,859,293 and U.S. Pat. No. 5,256,700 disclose techniques for extracting high purity carnosic acid from rosemary and sage. For example, U.S. Pat. No. 5,256,700 discloses a process for obtaining carnosic acid comprising extracting a vegetable material selected from the group consisting of sage and rosemary with an apolar solvent to obtain an extract containing apolar compounds including carnosic acid, contacting the extract with an adsorbent material having an affinity for polar compounds for adsorbing the carnosic acid to separate the carnosic acid from the apolar compounds of the extract, desorbing the adsorbent material with a polar solvent to obtain the carnosic acid in the solvent and then evaporating the polar solvent from the carnosic acid to obtain a residue containing the carnosic acid.
Mixtures of ethyl lactate and isoamyl lactate can beneficially be used to extract carnosic acid from Libiatae plants, such as rosemary, marjoram, and sage. For instance, a mixture containing from about 30 weight percent to 70 weight percent ethyl lactate and about 30 weight percent to about 70 weight percent isoamyl lactate can be used to extract carnosic acid from such Libiatae plants. In such a procedure, the mixture of ethyl lactate and isoamyl lactate is mixed with about 30 parts by weight to about 70 parts by weight of water and heated to a temperature which is within the range of about 70° C. to about 100° C. Then ground leaves of the Libiatae plant are mixed into the solution of the ethyl lactate, isoamyl lactate and water. Then the extract of the Libiatae plant is recovered by filtering it from the solid matter, such as leaves and plant material. At this point, the extract from the Libiatae plant can be employed in making the skin creams of this invention. It should be noted that additional ethyl lactate and/or isoamyl lactate can be added at attain the desired levels in the final skin cream.
Some methods for the preparation of carnosic acid by chemical synthesis have also been proposed in the literature by W. L. Meyer et al. [Tetrahedron Letters 1966, 4261; 1968, 2963; J. Org. Chem. 41, 1005 (1976)]. However, the syntheses involved are long and complex and, for economic reasons, cannot be applied to an industrial process. In addition, these syntheses lead to racemic mixtures of carnosic acid precursors and not to the pure enantiomers. It should also be pointed out that these works stop at the preparation of carnosic acid precursors and omit to describe the final preparation step(s). Another method of obtaining carnosic acid has been described in the literature by Brieskorn and Domling [Arch. Pharm. 302, 641 (1969)], comprising the catalytic reduction of carnosol. Once again, the application of this process on a large scale is not be envisaged because carnosol is not readily available on a commercial basis. For these reasons the carnosic acid used in the skin creams formulations of this invention will normally be obtained by extraction from a Libiatae plant, such as rosemary or marjoram. Accordingly, rosemary or marjoram extract will typically be used in the practice of this invention as the source of carnosic acid. However, to reduce the possibility of allergic reactions to the skin cream formulation the skin cream formulation will preferably be free of rosemary, sage, marjoram and other Libiatae plants.
It is preferred for the skin cream formulations of this invention to also contain idebenone. The idebenone will typically be present in the skin cream formulation at a level which is within the range of about 0.01 weight percent to about 5 weight percent. The idebenone will preferably be present in the skin cream formulation at a level which is within the range of about 0.05 weight percent to about 3 weight percent and will more preferably be present at a level which is within the range of about 0.1 weight percent to about 1 weight percent.
Palmitoyl pentapeptide can also be included in the skin cream formulations of this invention. Palmitoyl pentapeptide stimulates human fibroblasts to produce collagen and elastin which fight wrinkle formation and can reduce or eliminate existing wrinkles. However, as with all active ingredients in antiwrinkle creams palmitoyl pentapeptide needs to be delivered deep into the dermis of the skin structure to attain a maximum level of effectiveness. The topical skin cream formulations of this invention accordingly can be used to facilitate the delivery of the palmitoyl pentapeptide deep into the dermis of a patient. The palmitoyl pentapeptide will normally be included at a level which is within the range of about 0.05 weight percent to about 8 weight percent. The palmitoyl pentapeptide will more typically be included at a level which is within the range of about 0.5 weight percent to about 6 weight percent, and will preferably be include at a level which is within the range of about 1 weight percent to about 5 weight percent. The palmitoyl pentapeptide will more preferably be included at a level which is within the range of 2 weight percent to 4 weight percent.
It can be desirable to include other naturally occurring antioxidants in the skin cream compositions of this invention. For instance, the extract of the subripe berry of the plant Coffea arabica, from which the ripened and roasted coffee bean is also derived, can beneficially be utilized in the skin cream compositions of this invention. This extract is rich in natural polyphenolic antioxidants including condensed proanthocyanidins and chlorogenic, quinic, and ferulic acids. These polyphenolic antioxidants can be used in the skin cream individually or in various combinations to protect skin from free radical oxidative attack.
Skin cream formulations that are comprised of extracts of subripe berries of Coffea Arabica plants, at least one alkyl lactate, and a base cream can also be made in accordance with this invention. Such skin cream formulations will typically contain (1) a polyphenolic antioxidant selected from the group consisting of condensed proanthocyanidins, chlorogenic acid, quinic acid, and ferulic acid; (2) at least one an alkyl lactate, and (3) a base cream (a pharmaceutically acceptable carrier). It is typically preferred for a combination of ethyl lactate and isoamyl lactate to be used in such compositions. The total level of polyphenolic antioxidants present in such skin cream formulations will typically be within the range of 0.01 weight percent to 2 weight percent, based upon the total weight of the skin cream formulation. Skin cream formulations of this type will more typically contain from about 0.05 weight percent to about 1 weight percent polyphenolic antioxidants, based upon the total weight of the skin cream formulation.
In making the skin cream formulations of this invention the ascorbic acid, the zinc salt, the amino acid, the optional carnosic acid, the optional palmitoyl pentapeptide, the optional idebenone, and additional desired materials are mixed into a pharmaceutically acceptable carrier, such as a base cream. Pharmaceutically acceptable carriers are described in U.S. Pat. No. 7,022,317 and can be in any presentation form normally used in cosmetics or dermatology, and it may especially be in the form of an optionally gelled aqueous solution, a dispersion of the lotion type, optionally a two-phase lotion, an emulsion obtained by dispersing a fatty phase in an aqueous phase (oil/water emulsion) or conversely (water/oil emulsion), or a triple emulsion (water/oil/water or oil/water/oil emulsion) or a vesicular dispersion of ionic and/or nonionic type. These compositions are prepared according to usual methods. A composition in the form of an oil-in-water emulsion is preferably used according to this invention.
This composition may be more or less fluid and may have the appearance of a white or colored cream, an ointment, a milk, a lotion, a serum, a paste or a mousse. It may optionally be applied in the form of an aerosol. It may also be in solid form, in particular in the form of a stick. It may be used as a care product, and/or as a makeup product for the skin.
In a known manner, the composition used according to the invention may also contain adjuvants that are common in cosmetics, such as hydrophilic or lipophilic gelling agents, hydrophilic or lipophilic active agents, preserving agents, antioxidants, solvents, fragrances, fillers, UV-screening agents, pigments, odor absorbers and dyestuffs. The amounts of these various adjuvants are those conventionally used in the field under consideration, and, for example, from 0.01% to 20% relative to the total weight of the composition. Depending on their nature, these adjuvants may be introduced into the fatty phase, into the aqueous phase, or into lipid vesicles.
When the composition used according to the invention is an emulsion, the proportion of the fatty phase may range from 5% to 80% by weight and preferably from 5% to 50% by weight relative to the total weight of the composition. The oils, emulsifiers and co-emulsifiers used in the composition in emulsion form are chosen from those conventionally used in the field under consideration. The emulsifier and co-emulsifier are present in the composition in a proportion ranging from 0.3% to 30% by weight and preferably from 0.5% to 20% by weight relative to the total weight of the composition.
As oils that may be used in the invention, mention may be made of mineral oils (liquid petroleum jelly), oils of plant origin (avocado oil or soybean oil), oils of animal origin (lanolin), synthetic oils (perhydrosqualene), silicone oils (cyclomethicone) and fluoro oils (perfluoropolyethers). Fatty alcohols (cetyl alcohol), fatty acids and waxes (carnauba wax or ozokerite) may also be used as fatty substances.
As examples of emulsifiers and co-emulsifiers that may be used in the invention, mention may be made of fatty acid esters of polyethylene glycol such as PEG-100 stearate, and fatty acid esters of glycerol such as glyceryl stearate, or mixtures thereof.
Hydrophilic gelling agents that may be mentioned in particular include carboxyvinyl polymers (carbomer), acrylic copolymers such as acrylate/alkylacrylate copolymers, polyacrylamides, polysaccharides, natural gums and clays, and lipophilic gelling agents that may be mentioned include modified clays, for instance bentones, metal salts of fatty acids, hydrophobic silica and polyethylenes.
Dermabase cream, Unibase cream, and Vanicream are representative examples of commercially available base creams that can be used as the pharmaceutically acceptable carrier in the practice of this invention.
The topical formulations of this invention can also contain: (1) moisturizers, (2) depigmenting or propigmenting agents, (3) antimicrobial agents, (4) anti-pollution agents or free-radical scavengers, (5) NO-synthase inhibitors, (6) agents for stimulating the synthesis of dermal or epidermal macromolecules and/or for preventing their degradation, (7) agents for stimulating the proliferation of fibroblasts or keratinocytes and/or keratinocyte differentiation, (8) dermo-decontracting agents, (9) tensioning agents, (10) calmatives, (11) agents acting on the capillary circulation, and (12) agents acting on the energy metabolism of cells. Examples of these additional materials that can be included in the skin cream formulations of this invention include:
1. Moisturizers
The moisturizers that can be used in the skin cream formulations of this invention either act on the barrier function of the skin or as an occlusive compound. Mention may be made of ceramides, sphingoid-based compounds, lecithins, glycosphingolipids, phospholipids, cholesterol and its derivatives, phytosterols (stigmasterol, β-sitosterol or campesterol), essential fatty acids, 1,2-diacylglycerol, 4-chromanone, pentacyclic triterpenes such as ursolic acid, petroleum jelly and lanolin; or a compound that directly increases the water content of the stratum corneum, such as threalose and its derivatives, hyaluronic acid and its derivatives, glycerol, pentanediol, sodium pidolate, serine, xylitol, sodium lactate, polyglyceryl acrylate, ectoin and its derivatives, chitosan, oligosaccharides and polysaccharides, cyclic carbonates, N-lauroylpyrrolidonecarboxylic acid and N-α-benzoyl-L-arginine; or a compound that activates the sebaceous glands, such as steroid derivatives (such as DHEA, its 7-oxide and 17-alkyl derivatives and sapogenins) and vitamin D and its derivatives. These compounds may represent from 0.001% to 30% and preferably from 0.01% to 20% relative to the total weight of the composition according to the invention. The composition according to the present invention comprising the moisturizers mentioned above is advantageously intended for preventing or treating dryness of the skin and especially xerosis.
2. Depigmenting or Propigmenting Agent
The depigmenting agents that may be incorporated into the composition according to the present invention comprise, for example, the following compounds: kojic acid; ellagic acid; arbutin and its derivatives such as those described in patent applications EP-895 779 and EP-524 109; hydroquinone; aminophenol derivatives such as those described in patent applications WO 99/10318 and WO 99/32077, and in particular N-cholesteryloxycarbonyl-para-aminophenol and N-ethyloxycarbonyl-para-aminophenol; iminophenol derivatives, in particular those described in patent application WO 99/22707; L-2-oxothiazolidine-4-carboxylic acid or procysteine, and also its salts and esters; ascorbic acid and its derivatives, especially ascorbyl glucoside; and plant extracts, in particular extracts of liquorice, of mulberry and of skullcap, without this list being limiting.
Propigmenting agents that may be mentioned include the extract of burnet ( Sanguisorba officinalis ) sold by the company Maruzen, and extracts of chrysanthemum ( Chrysanthemum morifolium ). The composition according to the present invention comprising the depigmenting agents mentioned above is advantageously intended for preventing or treating hyperpigmentation, in particular pigmentation marks associated with ageing of the skin. For its part, the composition containing the propigmenting agents mentioned above is preferably intended for treating baldness.
3. Antimicrobial Agents
The antimicrobial agents that may be used in the composition according to the invention may be chosen especially from 2,4,4′-trichloro-2′-hydroxydiphenyl ether (or triclosan), 3,4,4′-trichlorobanilide, phenoxyethanol, phenoxypropanol, phenoxyisopropanol, hexamidine isethionate, metronidazole and its salts, miconazole and its salts, itraconazole, terconazole, econazole, ketoconazole, saperconazole, fluconazole, clotrimazole, butoconazole, oxiconazole, sulfaconazole, sulconazole, terbinafine, ciclopirox, ciclopiroxolamine, undecylenic acid and its salts, benzoyl peroxide, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, phytic acid, N-acetyl-L-cysteine acid, lipoic acid, azelaic acid and its salts, arachidonic acid, resorcinol, 2,4,4′-trichloro-2′-hydroxydiphenyl ether, 3,4,4′-trichlorocarbanilide, octopirox, octoxyglycerine, octanoylglycine, caprylyl glycol, 10-hydroxy-2-decanoic acid, dichlorophenyl imidazole dioxolane and its derivatives, described in patent WO 93/18743, farnesol and phytosphingosines, and mixtures thereof. The preferred antibacterial agents are triclosan, phenoxyethanol, octoxyglycerine, octanoylglycine, 10-hydroxy-2-decanoic acid, caprylyl glycol, farnesol and azelaic acid. By way of example, the antimicrobial agent may be used in the composition according to the invention in an amount representing from 0.1% to 20% and preferably from 0.1% to 10% relative to the total weight of the composition. The composition containing the antimicrobial agent is particularly suitable for use in treating acne-prone greasy skin, acne or scalp dandruff.
4. Anti-Pollution Agent or Free-Radical Scavenger
The term “anti-pollution agent” means any compound capable of trapping ozone, monocyclic or polycyclic aromatic compounds such as benzopyrene and/or heavy metals such as cobalt, mercury, cadmium and/or nickel. The term “free-radical scavenger” means any compound capable of trapping free radicals. As ozone-trapping agents that may be used in the composition according to the invention, mention may be made in particular of vitamin C and its derivatives including ascorbyl glucoside; phenols and polyphenols, in particular tannins, ellagic acid and tannic acid; epigallocatechin and natural extracts containing it; extracts of olive tree leaf; extracts of tea, in particular of green tea; anthocyans; extracts of rosemary; phenol acids, in particular chlorogenic acid; stilbenes, in particular resveratrol; sulphur-containing amino acid derivatives, in particular S-carboxymethylcysteine; ergothioneine; N-acetylcysteine; chelating agents, for instance N,N′-bis(3,4,5-trimethoxybenzyl)ethylenediamine or one of its salts, metal complexes or esters; carotenoids such as crocetin; and various starting materials, for instance the mixture of arginine, histidine ribonucleate, mannitol, adenosine triphosphate, pyridoxine, phenylalanine, tyrosine and hydrolysed RNA, sold by the Laboratoires Serobiologiques under the trade name CPP LS 2633-12F®, the water-soluble fraction of corn sold by the company Solabia under the trade name Phytovityl®, the mixture of extract of fumitory and of extract of lemon sold under the name Unicotrozon C-49® by the company Induchem, and the mixture of extracts of ginseng, of apple, of peach, of wheat and of barley, sold by the company Provital under the trade name Pronalen Bioprotect®.
As agents for trapping monocyclic or polycyclic aromatic compounds, which may be used in the composition according to the invention, mention may be made in particular of tannins such as ellagic acid; indole derivatives, in particular 3-indolecarbinol; extracts of tea, in particular of green tea, extracts of water hyacinth or Eichhornia crassipes ; and the water-soluble fraction of corn sold by the company Solabia under the trade name Phytovityl®.
Finally, as heavy-metal-trapping agents that may be used in the composition according to the invention, mention may be made in particular of chelating agents such as EDTA, the pentasodium salt of ethylenediaminetetra-methylenephosphonic acid, and N,N′-bis(3,4,5-trimethoxybenzyl)ethylenediamine or one of the salts, metal complexes or esters thereof; phytic acid; chitosan derivatives; extracts of tea, in particular of green tea; tannins such as ellagic acid; sulphur-containing amino acids such as cysteine; extracts of water hyacinth ( Eichhornia crassipes ); and the water-soluble fraction of corn sold by the company Solabia under the trade name Phytovityl®.
The free-radical scavengers that may be used in the composition according to the invention comprise, besides certain anti-pollution agents mentioned above, vitamin E and its derivatives such as tocopheryl acetate; bioflavonoids; coenzyme Q10 or ubiquinone; certain enzymes, for instance catalase, superoxide dismutase, lactoperoxidase, glutathione peroxidase and quinone reductases; glutathione; benzylidenecamphor; benzylcyclanones; substituted naphthalenones; pidolates; phytanetriol; gamma-oryzanol; lignans; and melatonin.
5. NO-Synthase Inhibitor
Examples of NO-synthase inhibitors that are suitable for use in the present invention especially comprise an extract of a plant of the species Vitis vinifera which is sold especially by the company Euromed under the name Leucocyanidines de raisins extra, or by the company Indena under the name Leucoselect®, or finally by the company Hansen under the name Extrait de marc de raisin; an extract of a plant of the species Olea europaea which is preferably obtained from olive tree leaves and is sold especially by the company Vinyals in the form of a dry extract, or by the company Biologia & Technologia under the trade name Eurol BT; and an extract of a plant of the species Gingko biloba which is preferably a dry aqueous extract of this plant sold by the company Beaufour under the trade name Gingko biloba extrait standard. The composition according to the invention comprising an NO-synthane inhibitor as defined above can advantageously be used to present or treat signs of ageing of the skin and/or sensitive skin.
6. Agent for Stimulating the Synthesis of Dermal or Epidermal Macromolecules and/or for Preventing their Degradation
Among the active agents for stimulating dermal macromolecules or for preventing their degradation, mention may be made of those that act: either on collagen synthesis, such as extracts of Centella asiatica; asiaticosides and derivatives ; ascorbic acid or vitamin C and its derivatives; synthetic peptides such as lamin, biopeptide CL or the palmitoyloligopeptide sold by the company Sederma; peptides extracted from plants, such as the soybean hydrolysate sold by the company Coletica under the trade name Phytokine®; and plant hormones such as auxins and lignans; or on elastin synthesis, such as the extract of Saccharomyces cerivisiae sold by the company LSN under the trade name Cytovitin®; and the extract of the alga Macrocystis pyrifera sold by the company Secma under the trade name Kelpadelie®; or on glycosaminoglycan synthesis, such as the product of fermentation of milk with Lactobacillus vulgaris , sold by the company Brooks under the trade name Biomin Yogourth®; the extract of the brown alga Padina pavonica sold by the company Alban Muller under the trade name HSP3; and the extract of Saccharomyces cerevisiae available especially from the company Silab under the trade name Firmalift® or from the company LSN under the trade name Cytovitin®; or on fibronectin synthesis, such as the extract of the zooplankton Salina sold by the company Seporga under the trade name GP4G®; the yeast extract available especially from the company Alban Muller under the trade name Drieline®; and the palmitoyl pentapeptide sold by the company Sederma under the trade name Matrixil®; or on the inhibition of metalloproteases (MMPs), such as, more particularly, MMP 1, 2, 3 or 9. Mention may be made of: retinoids and derivatives, oligopeptides and lipopeptides, lipoamino acids, the malt extract sold by the company Coletica under the trade name Collalift®; extracts of blueberry or of rosemary; lycopene; isoflavones, their derivatives or plant extracts containing them, in particular extracts of soybean (sold, for example, by the company Ichimaru Pharcos under the trade name Flavosterone SB®), of red clover, of flax, of kakkon, or of sage; or on the inhibition of serine proteases such as leukocyte elastase or cathepsin G. Mention may be made of: the peptide extract of Leguminosa seeds ( Pisum sativum ) sold by the company LSN under the trade name Parelastyl®; heparinoids; and pseudodipeptides such as {2-[acetyl-(3-trifluoromethylphenyl)amino]-3-methylbutynylamino}acetic acid.
Among the active agents that stimulate epidermal macromolecules, such as fillagrin and keratins, mention may be made especially of the extract of lupin sold by the company Silab under the trade name Structurine®; the extract of beech Fagus sylvatica buds sold by the company Gattefosse under the trade name Gatuline®; and the extract of the zooplankton Salina sold by the company Seporga under the trade name GP4G®.
The composition according to the invention containing one or more of the above compounds is particularly suitable for use in preventing or treating signs of ageing of the skin, in particular of loss of firmness and/or of elasticity of the skin.
7. Agent for Stimulating the Proliferation of Fibroblasts or Keratinocytes and/or Keratinocyte Differentiation
The agents for stimulating the proliferation of fibroblasts that may be used in the composition according to the invention may be chosen, for example, from plant proteins or polypeptides, extracts, especially of soybean (for example an extract of soybean sold by the company LSN under the name Eleseryl SH-VEG 8 or sold by the company Silab under the trade name Raffermine®); and plant hormones such as gibelrellins and cytokinins.
The agents for stimulating the proliferation of keratinocytes that may be used in the composition according to the invention especially comprise retinoids such as retinol and its esters, including retinyl palmitate; phloroglucinol; extracts of nut cakes sold by the company Gattefosse; and extracts of Solanum tuberosum sold by the company Sederma.
The agents for stimulating keratinocyte differentiation comprise, for example, minerals such as calcium; the extract of lupin sold by the company Silab under the trade name Photopreventine®; sodium beta-sitosteryl sulphate sold by the company Seporga under the trade name Phytocohesine®; and the extract of corn sold by the company Solabia under the trade name Phytovityl®; and lignans such as secoisolariciresinol. The composition according to the invention comprising these compounds is preferably intended to be used for preventing or treating signs of ageing of the skin.
8. Dermo-Decontracting Agent
The dermo-decontracting agents that may be used in the composition according to the invention comprise alverine and its salts, manganese gluconate, Diazepam, the hexapeptide argireline R sold by the company Lipotec, certain carbonylated secondary and tertiary amines, adenosine, and also sapogenins and the natural extracts, in particular of Wild Yam, containing them. The composition according to the invention comprising these compounds is preferably intended to be used for preventing or treating signs of ageing of the skin, and in particular wrinkles.
9. Tensioning Agent
The term “tensioning agent” means a compound capable of exerting tension on the skin, the effect of which is to temporarily fade out irregularities on the skin's surface, such as wrinkles, and fine lines. Among the tensioning agents that may be used in the composition according to the present invention, mention may be made especially of: (1) synthetic polymers, such as polyurethane latices or acrylic-silicone latices, in particular those described in patent application EP-1 038 519, such as a propylthio(polymethyl acrylate), propylthio(polymethyl methacrylate) and propylthio(polymethacrylic acid) grafted polydimethylsiloxane, or alternatively a propylthio(polyisobutyl methacrylate) and propylthio(polymethacrylic acid) grafted polydimethylsiloxane. Such grafted silicone polymers are sold especially by the company 3M under the trade names VS 80, VS 70 or LO21 (2) polymers of natural origin, especially (a) polyholosides, for example (i) in the form of starch derived especially from rice, corn, potato, cassaya, pea, Triticum aestivum wheat, oat, etc. or (ii) in the form of carrageenans, alginates, agars, gelans, cellulose-based polymers and pectins, advantageously as an aqueous dispersion of gel microparticles, and (b) latices consisting of shellac resin, sandarac gum, dammar resins, elemi gums, copal resins and cellulose-based derivatives, and mixtures thereof, (3) plant proteins and protein hydrolysates, in particular from corn, rye, Triticum aestivum wheat, buckwheat, sesame, spelt, pea, bean, lentil, soybean and lupin, (4) mixed silicates, especially phyllosilicates and in particular Laponites, (5) wax microparticles chosen, for example, from carnauba wax, candelilla wax and alfalfa wax, (6) colloidal particles of mineral filler with a number-average diameter of between 0.1 and 100 nm and preferably between 3 and 30 nm, chosen, for example, fiom: silica, silic-alumina composites, cerium oxide, zirconium oxide, alumina, calcium carbonate, barium sulphate, calcium sulphate, zinc oxide and titanium dioxide. The compositions according to the invention comprising the above tensioning agents are advantageously intended for treating signs of ageing of the skin, in particular wrinkles and fine lines.
10. Calmatives
As calmatives that may be used in the composition according to the invention, mention may be made of: pentacyclic triterpenes and extracts of plants (e.g.: Glycyrrhiza glabra ) containing them, for instance .beta.-glycyrrhetinic acid and salts and/or derivatives thereof (glycyrrhetinic acid monoglucoronide, stearyl glycyrrhetinate or 3-stearoyloxyglycyrrhetic acid), ursolic acid and its salts, oleanolic acid and its salts, betulinic acid and its salts, an extract of Paeonia suffruticosa and/or lactiflora, salicylic acid salts and in particular zinc salicylate, the phycosaccharides from the company Codif, an extract of Laminaria saccharina , canola oil, bisabolol and camomile extracts, allantoin, Sepivital EPC (phosphoric diester of vitamins E and C) from SEPPIC, omega-3 unsaturated oils such as musk rose oil, blackcurrant oil, ecchium oil, fish oil, plankton extracts, capryloylglycine, Seppicalm VG (sodium palmitoylproline and Nymphea alba ) from SEPPIC, an extract of Pygeum, an extract of Boswellia serrata , an extract of Centipeda cunnighami , an extract of Helianthus annuus , an extract of Linum usitatissimum, tocotrienols , extracts of Cola nitida , piperonal, an extract of clove, an extract of Epilobium angustifolium, Aloe vera , an extract of Bacopa moniera , phytosterols, cortisone, hydrocortisone, indomethacin and betamethasone.
11. Agents Acting on the Capillary Circulation
The active agents acting on the capillary circulation (vasoprotective or vasodilating agents) may be chosen from flavonoids, ruscogenins, esculosides, escin extracted from common horse chestnut, nicotinates, heperidine methyl chalcone, essential oils of lavender or of rosemary, and extracts of Ammi visnaga . The amount of these active agents may vary within a wide range. In general, these active agents are present in a concentration ranging from 0.01% to 15% and preferably from 0.05% to 10% by weight relative to the total weight of the composition.
12. Agents Acting on the Energy Metabolism of Cells
The active agents concerned are those acting on the energy metabolism of the skin, for instance, and in a non-limiting manner, ATP synthesis, and also those involved in the respiratory chain of the cell or in the energy reserves. Mention may be made of coenzyme Q10 (ubiquinone), cytochrome C, creatine or phosphocreatine.
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
In this experiment a topical skin cream was made utilizing Vanicream™ skin cream as the base cream. Vanicream™ skin cream is a non-greasy, non-comedogenic oil-in-water emulsion that consists of purified water, white petrolatum, cetearyl alcohol and ceteareth-20, sorbitol solution, propylene glycol, simethicone, glyceryl monostearate, polyethylene glycol monostearate, sorbic acid, and butylated hydroxytoluene (BHT). In the procedure used 1 g (gram) of ascorbic acid, 500 mg (milligrams) of zinc sulfate, 200 mg of idebenone, and 500 mg of phenylalanine were mixed into 10 grams of the Vanicream™ base cream. Then, the liquid components (1.5 g of α-tocopherol, 100 mg of ethyl lactate, and 50 mg of rosemary extract) were mixed into the formulation.
The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. It also provided a nice warm glow to skin onto which it was applied. This skin cream formulation had a slight odor, but was not obnoxious. It did not yellow after being stored at room temperature for three weeks.
EXAMPLE 2
In this experiment a topical skin cream was made using the procedure described in Example 1 except one drop of mango oil was added to the formulation with the liquid components. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. It also provided a nice warm glow to skin onto which it was applied. This skin cream formulation had a very pleasant mango fragrance. In fact, the odor of the ethyl lactate was completely masked. It did not yellow after being stored at room temperature for three weeks.
EXAMPLE 3
In this experiment a topical skin cream was made using the procedure described in Example 1 except that α-tocopherol was not included in the formulation. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. This skin cream formulation had a strong odor which was deemed to be obnoxious. This skin cream formulation yellowed significantly after being stored at room temperature for three weeks
EXAMPLE 4
In this experiment a topical skin cream was made using the procedure described in Example 1 except that the level of α-tocopherol was reduced to 500 mg. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. This skin cream formulation had a slight odor, but was not obnoxious. However, this skin cream formulation yellowed after being stored at room temperature for three weeks
EXAMPLE 5
In this experiment a topical skin cream was made using the procedure described in Example 1 except that the level of α-tocopherol was increased to 3 grams. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. It also provided a nice warm glow to skin onto which it was applied. This skin cream formulation had a slight odor, but was not obnoxious. However, this skin cream formulation yellowed significantly after being stored at room temperature for three weeks
EXAMPLE 6
In this experiment a topical skin cream was made using the procedure described in Example 1 except that 35 mg of isoamyl lactate was added to the formulation with the liquid components. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. This skin cream formulation had a slight odor, but was not obnoxious.
EXAMPLE 7
In this experiment a topical skin cream was made using the procedure described in Example 6 except that one drop of mango oil was added to the formulation with the liquid components. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. It also provided a nice warm glow to skin onto which it was applied. This skin cream formulation had a very pleasant mango fragrance. In fact, the odor of the ethyl lactate was completely masked.
EXAMPLE 8
In this experiment a topical skin cream was made using the procedure described in Example 1 except that tyrosine was substituted for the phenylalanine. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. It also provided a nice warm glow to skin onto which it was applied. This skin cream formulation had a slight odor, but was not obnoxious. It did not yellow after being stored at room temperature for three weeks.
EXAMPLE 9
In this experiment a topical skin cream was made using the procedure described in Example 8 except one drop of mango oil was added to the formulation with the liquid components. The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. It also provided a nice warm glow to skin onto which it was applied. This skin cream formulation had a very pleasant mango fragrance. In fact, the odor of the ethyl lactate was completely masked. It did not yellow after being stored at room temperature for three weeks.
EXAMPLE 10
In this experiment a topical skin cream was made utilizing Vanicream™ skin cream as the base cream. In the procedure used 1 g (gram) of ascorbic acid, 500 mg (milligrams) of zinc sulfate, 100 mg of idebenone, and 500 mg of phenylalanine were mixed into 10 grams of the Vanicream™ base cream. Then, the liquid components (1.5 g of α-tocopherol, 70 mg of ethyl lactate, 30 mg of isoamyl lactate, 50 mg of rosemary extract, and one drop of mango oil) were mixed into the formulation. The formulation was mixed with a stirring rod for about 5 minutes to attain a uniform cream composition.
This skin cream formulation made in this experiment had a very pleasant mango fragrance. The odor of the ethyl lactate was completely masked by the isoamyl lactate and the mango. This skin cream composition was evaluated as a facial cream by three adult females. These female subjects applied this skin cream to their faces in the morning after washing their faces. It was reported to have good moisturizing characteristics and was further reported to provide the facial skin to which it was applied with a warm glow. After the skin cream had been absorbed into the skin (dried) the subjects applied their makeup foundation as usual. All of the subjects reported that their foundation glided on more easily than usual. It was further reported that the skin cream composition made a good base for their foundation and helped to prevent the foundation from encrusting or caking. The subjects reported that their makeup did not dissipate and remained fresh over the course of the day. Accordingly, the subjects reported that the facial cream could conveniently be used in conjunction with makeup. None of the subject found the skin cream of this invention to be irritating and all of the subjects observed a reduction in roughness and dryness of their facial skin. All of the subjects further reported an improvement in the texture, softness, smoothness, tone, clarity, and radiance of their skin within 30 minutes of application.
EXAMPLE 11
One of the female subjects repeated the procedure described in Example 10, except that she applied MD Forté sunscreen to her face after allowing the facial cream of this invention to be absorbed into her skin. She again reported that her foundation makeup glided on more easily than usual. It was again reported that the skin cream composition made a good base for her foundation and helped to prevent it from encrusting or caking. She found that her makeup did not dissipate and remained fresh over the course of the day. She observed a reduction in roughness and dryness of her facial skin and again reported an improvement in the texture, softness, smoothness, tone, clarity, and radiance of her skin within 30 minutes of the application. Accordingly, she reported that the facial cream could conveniently be used as part of a daily regimen that includes the application of sunscreen followed by makeup.
EXAMPLE 12
In this experiment a marjoram extract containing carnosic acid was prepared. In the procedure used a mixture containing one part by weight ethyl lactate, one part by weight isoamyl lactate, and one part by weight distilled water was heated to about 90° C. Then, 4 grams of ground marjoram leaves were mixed into 12 grams of the liquid mixture and agitated for about 10 minutes. At that point, the mixture was filtered through a coffee filter to separate the liquid extract from the remaining solid material, such as leaves and plant matter. The marjoram extract was then used in making skin cream samples in accordance with this invention.
EXAMPLE 13
In this experiment a topical skin cream was made utilizing the marjoram extract made in Example 12. In the procedure used Vanicream™ skin cream was again used as the base cream. In the procedure used 1 g (gram) of ascorbic acid, 500 mg (milligrams) of zinc sulfate, 200 mg of idebenone, and 500 mg of phenylalanine were mixed into 10 grams of the Vanicream™ base cream. Then, 1.5 g of α-tocopherol and 150 mg of the marjoram extract were mixed into the formulation.
The topical skin cream formulation made was soothing when applied to dry skin and had good moisturizing characteristics. It also provided a nice warm glow to skin onto which it was applied. This skin cream formulation had a much more pleasing odor than did the formulation made in Example 1 with ethyl lactate and Rosemary extract. It was determined that the marjoram extract made in Example 12 was characterized by a much less intense odor than was exhibited by the Rosemary extract. In any case the skin cream made did not yellow after being stored at room temperature for three weeks.
EXAMPLE 14
In this experiment a topical skin cream was again made utilizing the marjoram extract made in Example 12. In the procedure used Vanicream™ skin cream was again used as the base cream. In the procedure used 12 g of ascorbic acid, 6 g of zinc sulfate, 1 g of BHT, and 7.5 g of phenylalanine were mixed into 300 grams of the Vanicream™ base cream. Then. 15 g of α-tocopherol, 1 g of the marjoram extract, and 1 g of cucumber melon perfume oil were mixed into the formulation. The skin cream made in this experiment did not yellow after being stored at room temperature for over four months.
This skin cream formulation was then used to treat a male patient suffering from chronic dry skin on his hand. This patient was 58 years old and had suffered from severe dry skin (xerosis) on the palmar of his hand for many years. In fact, this patient's dry skin was so pronounced that it frequently developed painful cracks in the skin (fissures) with bleeding occurring from time to time. Over the years this patient had treated his chronic dry skin condition with a wide variety of moisturizing agents without success. However, the skin cream made in this experiment was very effective in reversing the xerosis after it was applied topically. In fact, the topical application of the skin cream of this invention to this patient's hand eliminated the fissures and bleeding. After a few days of applying the skin cream of this invention his skin was reported to have returned to normal.
EXAMPLE 15
In this experiment a topical skin cream was again made utilizing the marjoram extract made in Example 12. In the procedure used Vanicream™ skin cream was again used as the base cream. In the procedure used 12 g of ascorbic acid, 6 g of zinc sulfate, 1 g of idebenone, 1 g of BHT, and 7.5 g of phenylalanine were mixed into 300 grams of the Vanicream™ base cream. Then, 15 g of α-tocopherol, 1 g of the marjoram extract, and 1 g of honeysuckle perfume oil were mixed into the formulation. The skin cream made in this experiment did not yellow after being stored at room temperature for over four months. It was also reported to exhibit a very pleasant fragrance.
This skin cream formulation was then used to treat a female patient suffering from chronic dry skin on her feet. This patient was 79 years old and suffered from xerosis on her feet. In fact, this patient's dry skin was so pronounced that it frequently developed painful fissures in the skin with bleeding occurring from time to time. Over the years this patient had treated her chronic dry skin condition with a wide variety of moisturizing agents without complete success. However, the topical application of the skin cream made in this experiment was very effective with regard to normalizing this patient's skin. In fact, the topical application of the skin cream of this invention to this patient's feet completely eliminated her problem with xerosis of the feet. After a few days of applying the skin cream of this invention the skin on her feet was reported to have returned to normal.
EXAMPLE 16
In this experiment a topical skin cream was again made utilizing the marjoram extract made in Example 12. In the procedure used Vanicream™ skin cream was again used as the base cream. In the procedure used 12 g of ascorbic acid, 6 g of zinc sulfate, 1 g of idebenone, 1 g of BHT, and 7.5 g of phenylatanine were mixed into 300 grams of the Vanicream™ base cream. Then, 15 g of α-tocopherol, 1 g of the marjoram extract, and 1 g of tangerine perfume oil were mixed into the formulation. The skin cream made in this experiment did not yellow after being stored at room temperature for over four months. It was also reported to have a pleasant fragrance.
This skin cream formulation was then used to treat a female patient suffering from xerosis on both of her elbows. The skin on the elbows of this patient was cracked, peeling and discolored. This patient was 49 years old and had previous treated her asteatotic condition of her elbows with a variety of over-the-counter moisturizing creams. However, the over-the-counter commercial products were not effective in moisturizing this patient's elbows. However, the topical application of the skin cream made in this experiment was very effective with regard to moisturizing the dry skin on this patient's elbows. In fact, the topical application of the skin cream of this invention to this patient's elbows completely eliminated her problem within a few days.
EXAMPLE 17
In this experiment a topical skin cream was again made utilizing the marjoram extract made in Example 12. In the procedure used Vanicream™ skin cream was again used as the base cream. In the procedure used 12 g of ascorbic acid, 6 g of zinc sulfate, 1 g of idebenone, 1 g of BHT, and 7.5 g of phenylalanine were mixed into 300 grams of the Vanicream™ base cream. Then, 15 g of α-tocopherol, 1 g of the marjoram extract, and 1 g of mango perfume oil were mixed into the formulation. The skin cream made in this experiment did not yellow after being stored at room temperature for over four months. It was also reported to have a pleasant fragrance.
The facial skin of a 49 year old female patient was evaluated utilizing a Visia Complexion Analysis and Statistical Modeling Engine version 1.2.0 made by Canfield Imaging Systems to establish a base line with respect to spots, pores, wrinkles, and texture. After being evaluated, this patient applied the skin cream made in this experiment to her face both in the morning and evening every day. After approximately four months the facial skin of this patient was re-evaluated after using this cream on a daily basis. This analysis showed a 3% reduction in spots, a 29% reduction in pores, a 29% reduction in wrinkles and a 26% improvement in skin texture. This patient was elated with the overall improvement in the appearance of her skin and was particularly delighted with the perceived reduction in pore size.
EXAMPLE 18
In this experiment a topical skin cream was again made utilizing the marjoram extract made in Example 12. In the procedure used Vanicream™ skin cream was again used as the base cream. In the procedure used 12 g of ascorbic acid, 6 g of zinc sulfate, 1 g of idebenone, 1 g of BHT, and 7.5 g of phenylalanine were mixed into 300 grams of the Vanicream™ base cream. Then, 15 g of α-tocopherol, 1 g of the marjoram extract, and 1 g of mango perfume oil were mixed into the formulation. The skin cream made in this experiment did not yellow after being stored at room temperature for over four months. It was also reported to have a pleasant fragrance.
The facial skin of a 49 year old female patient was evaluated utilizing a Visia Complexion Analysis and Statistical Modeling Engine version 1.2.0 made by Canfield Imaging Systems to establish a base line with respect to spots, pores, wrinkles, and texture. After being evaluated, this patient applied the skin cream made in this experiment to her face both in the morning and evening every day. After approximately four months the facial skin of this patient was re-evaluated after using this cream on a daily basis. This analysis showed a 38% reduction in spots, a 58% reduction in pores, a 40% reduction in wrinkles and a 54% improvement in skin texture. This patient was elated with the dramatic improvement in the appearance of her skin.
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. | The subject invention relates to a skin cream that can be used to moisturize and rejuvenate skin that has been damaged by exposure to sunlight or which has simply been affected over the years by intrinsic aging. It inhibits the formation of wrinkles and in some cases reduces the depth of existing wrinkles or eliminates them entirely. This invention is based upon the discovery that alkyl lactates, such as ethyl lactate, can be used to improve the penetration of active ingredients in skin care formulations deep into lower layers of the skin tissue. The present invention more specifically discloses a topical formulation comprising ascorbic acid, an amino acid selected from the group consisting of phenylalanine and tyrosine, a non-toxic zinc salt, an alkyl lactate, and a pharmaceutically acceptable carrier. | 0 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.