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In methods of assembling parts together, in particular automotive bodywork parts, it is common practice to bring the various parts for assembly to an assembly station where they are firstly put accurately into position relative to one another, and secondly they are held in position firmly so as to ensure that any forces applied to them by the assembly tooling (welding clamps in particular) do not disturb, alter, or modify their intended positions and thus the general shape of the assembly once it has been made.
BACKGROUND OF THE INVENTION
An assembly station is fed with parts for connecting to one another by a handling tool (a robot) which “entrusts” the part it is transporting to tooling specific to the assembly station, which tool then ensures that the part is put accurately into place and is clamped firmly in place. That conventional disposition suffers from the major drawback of requiring the assembly station to implement tools that are dedicated to each of the parts received. Consequently, to switch from manufacturing one product to another, although it is possible to retain a single handling robot, it is necessary to change the tooling for positioning and clamping the parts relative to the assembly station. That requirement constitutes a major limit on assembly station flexibility, i.e. on its capacity to receive different types of part. It is necessary to have one set of tools for each part and to fit the station with tool-changing means so that such a changeover can be performed as quickly as possible. The assembly station then becomes very cluttered by means for handling these sets of tools (which are often presented in the form of prefitted pallets. It is also necessary for the handling means to be manufactured with care so that the sets of tools are put into place as accurately as possible within the station and do not give rise to unacceptable dispersion in the accuracy with which the parts for assembling together are put into place. Furthermore, such tool changes still require time and that constitutes a factor for lengthening assembly cycle times, which necessarily leads to increased production costs.
Nowadays, the accuracy of handling robots concerning control over the paths they follow and the coordinates of the starting and ending positions of each such path are becoming entirely compatible with the accuracy required for positioning parts in the frame of reference of an assembly station. As a result, it is possible merely by changing the programming of a handling robot to put various different parts accurately into place in an assembly frame of reference within which, likewise by suitable and varying programming, it is possible to give accurate positions to assembly tools such as welding clamps.
It is thus possible to eliminate the specific positioning tools that were previously necessary in assembly stations. Unfortunately, the structure of a robot is unsuitable for withstanding the forces to which parts are subjected by the action of the assembly tools in order to keep each part firmly in position during an assembly operation (e.g. by welding). This leads to a major risk of the resulting assembly having the wrong shape.
OBJECTS AND SUMMARY OF THE INVENTION
The present invention seeks to provide a solution for use in assembling parts (at least two parts) and in particular automotive bodywork parts, which takes advantage of the accuracy of robots to simplify considerably the tooling of assembly stations and thus make them suitable for accepting parts of different shapes, with the consequence of making such stations very flexible in use.
To this end, the invention provides a method of holding a part in position in an assembly station, in which method the part is put into a determined position in the frame of reference of the assembly station by means of a handling robot, at least one clamp is closed onto a portion secured to the part, the clamp being mounted to slide freely in a guide of the assembly station extending parallel to its own clamping direction, and the clamp is blocked against sliding when it is clamped onto the part.
In other words, in the method of the invention, once the part has been put into place by the positioning robot, the part is clamped onto a support which forms part of the assembly station while ensuring that the clamping forces do not constitute parasitic forces concerning the positioning of the part, given that the robot which holds the part in position is not capable of opposing such forces adequately. For example, it will be understood that a clamp which is mounted to slide on the above-mentioned support along a guide parallel to the clamping direction of its jaws cannot exert a force in the sliding direction. Consequently, in theory, clamping does not cause the part to move at all. Once the part has been gripped between the jaws, it suffices to lock a clamp in its guide to ensure that the part is clamped on the support without its position as defined by the robot being altered.
There are several ways in which the clamps can be locked, i.e. in which its degree of freedom along its guide can be eliminated. In a first embodiment, sliding is locked by clamping at least one second sliding clamp having a sliding direction that is not parallel to the sliding direction of the first clamp whose freedom to move along its guide is to be eliminated.
In a second embodiment, sliding is locked by a brake, which acts between the guide and the clamp-carrier slider.
Depending on the shape of the assembly to be made, the number of parts to be put into position relative to one another in the assembly station, the size of these parts, the holds which the handling robot must have on them, and the freedom of access that needs to be left for the assembly tools, the clamps for clamping the part on the support forming a portion of the assembly station act either directly on the part, or else they act on a portion of the robot close to its part-gripping end.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics and advantages of the invention appear from the following description given in non-limiting manner of two embodiments of the invention.
Reference is made to the accompanying drawings, in which:
FIG. 1 is a diagram showing how a part can be clamped in an assembly station relative to three orthogonal axes of the frame of reference of the assembly station; and
FIG. 2 shows a variant embodiment of a device implementing the method of the invention.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1 , a table 1 represents the basic structure of an assembly station. Three clamping means 2 , 3 , and 4 are placed on the table together with a metal sheet 5 that is to be assembled, e.g. via spot welds 6 , to another part placed in the assembly station and not shown. The metal sheet 5 is brought into the frame of reference of the assembly station and is positioned accurately therein by a robot 7 represented diagrammatically merely by a grip 7 a to which the part 5 is coupled by known means (clip fastening, suction cup, . . . ).
For explanatory purposes, the part 5 is shown as having two side tongues 5 a and 5 b which are used for clamping the part in a plane parallel to the plane of the support 1 of the assembly station.
Also for reasons of explanation, each of the clamping means is shown as being in the form of a clamp, and comprising for the means 2 , for example: two jaws 8 and 9 slidably mounted in a body 10 having slideways 11 and capable of being moved apart from or towards each other, e.g. by means of an actuator which is not shown but which is housed inside the body 10 .
The body 10 itself forms a slider mounted to slide freely on a guide 12 which is securely fixed to the table 1 of the assembly station. At its ends, the guide 12 has fixed stops 13 and 14 for the jaws 8 and 9 in order to limit their maximum spacing.
The members 3 and 4 shown diagrammatically in FIG. 1 are of the same structure as the member 2 . Nevertheless, it should be observed that the member 3 is orthogonal to the member 2 and that the member 4 is orthogonal both to the member 2 and to the member 3 . The slides 10 of each of the members 2 , 3 , and 4 which are parallel to the clamping and unclamping directions of the is jaws 8 and 9 they comprise, are therefore not parallel to one another.
When the assembly station is waiting for the part 5 , the jaws in each pair of jaws are maximally spaced apart from each other, i.e. they are pressed against the stops 13 and 14 in each clamping member. Furthermore, the member 4 which provides vertical clamping for the part 5 is retracted, either by being tilted as represented by arrow A or by being rotated about an axis perpendicular to the support 1 as represented by arrow B. The maximum opening of each clamp defines the maximum size of the portion of a part that it can hold. It will thus be understood that various different parts can be received by said clamping means.
The robot 7 positions the part in the frame of reference of the assembly station while the clamping members are in a waiting position. Once the part is in its final position, a controller (not shown) acting on the displacement actuators of the jaws causes the jaws to move towards each other in pairs. Before this is done, for the member 4 that clamps the part vertically, orders are given to bring it into operation by rotating or tilting as represented by the arrow A or B.
It will be understood that while the clamping members are being tightened, one of the jaws will come to bear against the part 5 so that continued tightening causes the other jaw to come closer while simultaneously causing the support 10 on each member to slide freely. Thus, the amount of force actually applied against the part 5 is minimal, being no more that required to overcome the friction between the slider 10 and the guide 11 , and this force can be minimized if high performance guide members are implemented between the slide and the guide, e.g. balls or surfaces having a very low coefficient of friction, and given the small size of this force it can be accommodated by the robot without the robot being deformed and thus without the position of the part 5 being modified.
Once tightening has been completed, i.e. once the jaws are clamped onto the part 5 with a determined amount of force, the part is accurately held in the frame of reference of the assembly station and the clamping forces holding it are sufficient to withstand the forces to which the part 5 will be subjected by the welding tools when performing the spot welds 6 without the part being moved.
It will be understood that any displacement of the slide 10 along its guide 12 is firmly opposed by the clamping performed by the member 3 and the member 4 . The same applies to sliding of the slides of said members 3 and 4 . This is achieved because the linear degree of freedom of the slide of each clamping member extends in a direction which is not parallel to the direction of either of the others.
In a variant embodiment, e.g. applicable when it is not possible to ensure that the sliding directions of the various clamping means are non-parallel, or applicable as an additional degree of security by eliminating the degree of freedom of each slider, it is possible for the apparatus to include means for locking each slider relative to its guide, as represented diagrammatically for the means 2 , as an actuator 15 acting on a shoe for braking or locking the slider 10 relative to the guide 12 .
Finally, in other circumstances, it can be advantageous to provide an additional degree of freedom to the clamping devices of the invention, e.g. consisting in the guide 12 itself being secured to the infrastructure (support 1 ) of the assembly station via an axis of rotation extending orthogonally to the sliding direction of the jaws. In the same manner as described above, this degree of freedom in rotation can be controlled either by the other clamping means becoming clamped, or else or in addition by implementing means for eliminating this degree of freedom in rotation (brakes, locking, . . . ).
Whereas the part is clamped in position in the assembly station in FIG. 1 by means which act directly on the part, FIG. 2 shows a variant embodiment in which the portion 7 a of the robot for gripping the part 16 that has been positioned in the assembly station itself has extensions 7 b , 7 c which are engaged by the clamping means 17 , 18 , 19 . Clamping operates on the same principle as that described with reference to FIG. 1 , and the means 17 , 18 , and 19 have the same characteristics. This disposition is advantageous insofar as it is desirable, for example, to leave a sufficiently large amount of access within the assembly station in the vicinity of the part for the assembly tools, which can be welding clamps. | A method of holding a part ( 5, 16 ) in position in an assembly station ( 1 ), in which the part ( 5 ) is put into a determined position in the frame of reference of the assembly station ( 1 ) by way of a handling robot ( 7 ), at least one clamp ( 2, 3, 4 ) is closed onto a portion ( 5 a , 5 b ) secured to the part, the clamp being mounted to slide freely in a guide ( 12 ) of the assembly station ( 1 ) extending parallel to its own clamping direction, and the clamp is blocked against sliding when it is clamped onto the part. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of co-pending U.S. application Ser. No. 11/365,413, filed Mar. 1, 2006. This application hereby incorporates by reference the foregoing related application.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a backflow prevention device and, in particular, to a removable cartridge housing check valves, a relief valve cartridge, and/or a self cleaning check valve for a backflow prevention device.
BACKGROUND OF THE INVENTION
[0003] Backflow prevention devices are used to protect potable water supplies from contamination. Backflow prevention devices are typically installed in pipelines between a main water supply and service lines that feed users such as industrial or commercial sites or residences. Many localities legally mandate their use.
[0004] Backflow is caused by abnormalities in the water distribution system such as backpressure or backsiphonage. Backpressure occurs when the water pressure is higher in the downstream system than in the water supply. Backsiphonage can occur when the water supply pressure drops, such as when a water main breaks or severe demands are placed on the water supply. Either condition could lead to backflow, the flow of water from the downstream system back into the water supply. Backflow is undesirable because it may cause contamination of the potable water supply.
[0005] Two common types of assemblies are the double check (DC) and the reduced pressure (RP) backflow prevention devices. The double check devices, commonly used with non-health hazards, have two check valves between two shut-off valves. The reduced pressure devices, commonly used to prevent health hazard, have two check valves, with a relief valve located between them, and two shut-off valves.
[0006] Backflow prevention devices commonly include two independently acting check valves, internally loaded to a closed position. Each check valve permits water flow in only a single direction, from the main water supply toward the service line. If the pressure drop across a check valve falls below a predetermined threshold, typically about 1 psi, the loading of the check valve should cause it to close, thereby preventing the flow of water backwards through the device. The first check valve (in the direction of flow) provides redundancy in case of failure of the second check valve.
[0007] Some backflow prevention devices further include a hydraulically operated relief valve to vent the zone between the two check valves to atmosphere. The relief valve is configured so that if the pressure in the zone between the two check valves gets within a predetermined threshold of the supply pressure, typically about 2 psi, the relief valve will open and dump water from the zone. The relief valve is usually installed over a drain or plumbed to a drain with an appropriate air gap.
[0008] Ball valves are provided upstream and downstream of backflow prevention devices, allowing isolation of the device. Test cocks provide the ability to measure pressure at various points in the backflow prevention device and to supply water at desired pressures for purposes of testing the functionality of the check valves to insure proper operation of the device without removing the device from the water line. Test cocks are typically located at four sites: on the upstream side of the inlet ball valve; between the inlet ball valve and the first check valve; between the two check valves; and between the second check valve and the outlet ball valve.
[0009] It is desirable to access the check valves or the relief valve (when present) from time to time for purposes of inspection, maintenance, repair, or replacement. With current backflow prevention devices, this generally requires either removing the device from the water line or accessing the valves through ports provided on the device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is an cutaway side view of a preferred embodiment of a backflow prevention device embodying features of the present invention;
[0011] FIG. 2 is a perspective view of the backflow prevention device of FIG. 1 ;
[0012] FIG. 3 is cutaway view of a slider receiver of the backflow prevention device of FIG. 1 ;
[0013] FIG. 4 is a cutaway view of a slider of the backflow prevention device of FIG. 1 ;
[0014] FIG. 5 is an exploded view of a check valve assembly of the backflow prevention device of FIG. 1 ;
[0015] FIG. 6 is a cutaway side view of an alternative embodiment of a backflow prevention device embodying features of the present invention;
[0016] FIG. 7 is a perspective view of a slider receiver of the backflow prevention device of FIG. 6 ; and
[0017] FIG. 8 is a cutaway perspective view of a relief valve of the backflow prevention device of FIG. 6 ;
[0018] FIG. 9 is a cutaway side view of an alternative embodiment of a backflow prevention device embodying features of the present invention;
[0019] FIG. 10 is a perspective view of a main body of the backflow prevention device of FIG. 9 ;
[0020] FIG. 11 is a perspective view of a main body and check valve cartridge of the backflow prevention device of FIG. 9 having the check valve cartridge in an extended position;
[0021] FIG. 12 is a perspective view of a main body and check valve cartridge of the backflow prevention device of FIG. 9 having the check valve cartridge in a retracted position;
[0022] FIG. 13 is an exploded view of a check valve cartridge of the backflow prevention device of FIG. 9 ; and
[0023] FIG. 14 is an exploded view of an alternative embodiment of a check valve cartridge of the backflow prevention device of FIG. 9 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] In FIG. 1 , there is illustrated a backflow prevention device 2 . A main body 4 provides structural support for the other components and defines fluid flow passages 6 , 8 at each end of the main body 4 . Test ports 10 , 12 are each in fluid communication with one of the fluid flow passages 6 , 8 via a test port channel 18 , 20 . The test ports 10 , 12 allow for evaluation of the function of the backflow prevention device 2 in a manner described below. A test port valve 22 , 24 is attached to each test port 10 , 12 .
[0025] An inlet ball valve 26 and an outlet ball valve 28 make it possible to isolate the backflow prevention device 2 from the water system to which it is connected. The inlet ball valve 26 is mounted in a ball valve housing 30 which is mounted to the main body 4 , preferably by means of a threaded engagement. The ball valve housing 30 may comprise a mounting portion 36 and a valve containment portion 38 , each defining a fluid flow passage 40 , 42 respectively. A test port 14 is in fluid communication with the fluid flow passage 40 of the valve containment portion 38 via a test port channel 44 . A test port valve 46 is attached to the test port 14 . The upstream end 48 of the ball valve housing 30 is configured for connection to a source of water, preferably via internal threads 50 .
[0026] The outlet ball valve 28 is mounted in a second ball valve housing 52 which is mounted to the main body 4 , preferably by means of a threaded engagement. The second ball valve housing 52 may comprise a mounting portion 58 and a valve containment portion 60 , each defining a fluid flow passage 62 , 64 . The downstream end 56 of the second ball valve housing 52 is configured for connection to a downstream system, preferably via internal threads 66 .
[0027] Referring now to FIG. 2 , the main body 4 comprises an upstream portion 112 and a downstream portion 114 , each having a fluid flow path 6 , 8 ( FIG. 1 ) respectively, therethrough. Generally flat, parallel bridging portions 120 , 122 join the upstream portion 112 and downstream portion 114 of the main body 4 . The upstream portion 112 , the downstream portion 114 and the two bridging members 120 , 122 define a generally rectangular access passage 124 through the main body 4 . The access passage facilitates the installation, removal, and manipulation of a removable cartridge, denoted generally by the reference numeral 68 .
[0028] Referring again to FIG. 1 , the removable cartridge 68 is mounted in the main body 4 . The removable cartridge 68 comprises a slider receiver 70 and a slider 72 . The slider receiver 70 , best seen in FIG. 3 , defines a fluid flow passage 74 . A test port 16 is in fluid communication with the fluid flow passage 74 of the slider receiver 70 via a test port channel 76 . A test port valve 78 is attached to the test port 16 . In the preferred embodiment, the upstream end 80 of the slider receiver 70 is configured to fit with the main body 4 . An o-ring 82 ( FIG. 1 ), held in place by a groove 83 in the outer surface of the slider receiver 70 , provides for a water tight seal between the slider receiver 70 and the main body 4 . The downstream portion 84 of the slider receiver 70 is configured to receive the upstream portion 86 of the slider 72 , best seen in FIG. 4 . The downstream portion 84 of the slider receiver 70 contains female threads 90 configured for engagement with male threads 92 on the upstream portion 86 of the slider 72 .
[0029] A first check valve 94 ( FIG. 1 ) is located in the slider receiver 70 . A ridge 96 on the inside surface of the slider receiver 70 helps to fix the check valve 94 in position against the main body 4 when the removable cartridge 68 is mounted in the main body 4 . The check valve 94 is of a standard type well known in the industry and is biased to a normally closed position. The check valve allows flow through the valve in only one direction, downstream.
[0030] Referring now to FIG. 5 , the check valve 94 comprises a valve seat 150 and a valve cage 152 . A valve seal 154 is fixed to a plunger 158 using a seal retainer 156 . The plunger 158 fits into a central bore 160 in the valve cage 152 and is free to move in a reciprocating fashion within the central bore 160 of the valve cage 152 . A spring 162 provides force to bias the check valve 94 toward a closed position.
[0031] It is desirable that the plunger 158 not stick within the central bore 160 lest the check valve 94 jam in an open position. Under reverse flow conditions, contaminated water will flow into the valve cage 152 from the normally downstream direction. Spiral grooves 164 are provided in the central bore 160 in order to assist the plunger 158 in flushing any particulate matter that might have flowed into the central bore and reducing the chance of the particulate matter wedging between the plunger 158 and the central bore 160 and causing the check valve 94 to stick.
[0032] The downstream end of the slider 72 , best seen in FIG. 1 , is configured to fit with the main body 4 . An o-ring 98 , held in place by a groove 99 ( FIG. 4 ) in the outer surface of the slider 72 , provides for a water tight seal between the slider 72 and the slider receiver 70 downstream of the threads 90 . A second check valve 100 is located in the slider 72 . A ridge 102 on the inside surface of the slider 72 helps to fix the position of the check valve 100 against the main body 4 when the removable cartridge 68 is mounted in the main body 4 . An o-ring 104 , held in place by a groove 105 in the outer surface of the slider 72 , provides for a water tight seal between the slider and the main body 4 .
[0033] Under normal operating conditions, if the water flow through the backflow prevention device 2 reduces to the point that the pressure drop across the second check valve 100 is less than 1.0 psi, the second check valve 100 would close, preventing flow in the reverse direction. If the second check valve 100 fails, the first check valve 94 would close, providing backup protection.
[0034] A geared or knurled exterior surface 106 allows for manual rotation of the slider 72 relative to the slider receiver 70 and the main body 4 . Rotating the slider 72 in one direction causes the slider 72 to telescopically screw into the slider receiver 70 , thereby reducing the overall length of the removable cartridge 68 and facilitating the removal of the cartridge 68 from the main body 4 .
[0035] Removing the cartridge 68 makes it possible to inspect, maintain, repair, or replace the check valves 94 100 . After inspecting or servicing the check valves 94 , 100 the cartridge 68 can be replaced by inserting either end of the cartridge 68 into the main body 4 and then unscrewing the slider 72 from the slider receiver 70 until the two ends of the cartridge 68 seat against the main body 4 .
[0036] Many localities and several industry organizations mandate the location of the four test ports 10 , 12 , 14 , 16 as described herein. The test ports 10 , 12 , 14 , 16 allow testing of the functionality of the backflow prevention device 2 without removing the device 2 from the water supply system. For example, pressure sensors can be attached to the test ports 10 , 12 , 14 , 16 and the various pressure readings compared. Under normal operating conditions, the pressure should drop as we move from each test port to the next downstream and the static pressure drop across each check valve 94 , 100 should be at least 1.0 psi. If the pressure downstream of a check valve 94 , 100 is greater than the pressure upstream of the check valve 94 , 100 , or if the downstream pressure is within 1.0 psi of the upstream pressure, the check valve 94 , 100 should close and prevent flow back through the check valve 94 , 100 .
[0037] Alternatively, the backflow prevention device 2 can be isolated from the water supply system by closing both of the ball valves 26 , 28 by rotating the ball valve handles 108 , 110 ( FIG. 2 ). Water can then be supplied to the individual test ports 10 , 12 , 14 , 16 at various pressures in order to exercise and test the individual check valves 94 , 100 . When water is supplied to a test port immediately downstream of a check valve at a pressure greater than the water upstream of the check valve, the check valve should close and no water should flow through the valve. Conversely, when the water pressure upstream of the check valve is sufficiently higher than the water pressure downstream of the check valve, the valve should open and water should flow through the check valve.
[0038] FIG. 6 depicts an alternative embodiment of a backflow prevention device 200 with a removable cartridge 202 . The removable cartridge 202 comprises a slider receiver 204 and a slider 206 . The slider receiver 204 is configured as described above, but with the addition of a relief valve docking station 208 . A relief valve 210 is mounted in a relief valve cap 220 which is attached to the docking station 208 , preferably by means of a threaded engagement. The relief valve cap 220 has an exit port 222 . A relief channel 214 in the slider receiver 204 provides fluid communication between the fluid flow path 212 in the zone between the two check valves 216 , 218 and the relief valve 210 .
[0039] FIG. 7 shows a perspective view of the slider receiver 204 and relief valve docking station 208 . Two supply pressure channels 224 , 226 provide fluid communication between the flow path 212 ( FIG. 6 ) on the upstream side of the first check valve 216 and the relief valve 210 .
[0040] As best seen in FIG. 8 , relief valve 210 ( FIG. 6 ) comprises a valve seat 228 and a valve seal 230 . A flexible diaphragm 232 divides the valve into a supply pressure chamber 234 and a control pressure chamber 236 . Water is supplied to the supply pressure chamber 234 via the supply pressure channels 224 , 226 ( FIG. 7 ). Water is supplied to the control pressure chamber 236 via the relief channel 214 . Water from the relief channel 214 flows through a channel 238 in a relief valve spacer 240 , around the diaphragm 232 via gaps between the spacer 240 and the relief valve cap 220 ( FIG. 6 ), and into the control pressure chamber 236 beneath the diaphragm 232 . A spring 242 provides a force biasing the relief valve 210 toward an open position.
[0041] When the supply water pressure is greater than the pressure in the zone between the two check valves 216 , 218 , by more than a predetermined threshold, typically about 2 psi, the pressure in the supply pressure chamber 234 is sufficient to overcome the force of the water in the control pressure chamber 236 and the biasing force of the spring 242 . If the pressure in the zone between the two check valves 94 , 100 should approach within 2 psi of the supply pressure, the relief valve 210 opens and water from the zone is vented to atmosphere.
[0042] Under normal operating conditions, if water flow through the backflow prevention device 200 reduces to the point that the pressure drop across the second check valve 218 is less than 1.0 psi, the second check valve 218 should close, preventing flow in the reverse direction. If the second check valve 218 fails, the first check valve 216 should close, providing backup protection. If the second check valve fails 218 , or if it does not seal tightly, leakage back through the valve 218 will cause the pressure in the zone between the two check valves 216 , 218 to increase. If the pressure in the zone between the two check valves 216 , 218 gets within a predetermined threshold of the supply pressure, typically about 2 psig, the relief valve 210 will open, dumping water from the zone between the two check valves 216 , 218 out to atmosphere through the exit port 222 , thereby reducing the possibility of contaminated water flowing back through the device 200 to the water supply system. Ordinarily, the relief valve 210 should be installed over a drain or plumbed to a drain with an appropriate air gap.
[0043] A second alternative embodiment of a backflow prevention device 302 is depicted in FIGS. 9-14 . A main body 304 provides structural support for the other components. The main body 304 comprises an upstream portion 412 and a downstream portion 414 , each having a fluid flow path 306 , 308 , respectively, therethrough at opposite ends of the main body 304 . The test ports 310 , 312 are in fluid communication with the fluid flow passages 306 , 308 via test port channels 318 , 320 , respectively. The test ports 310 , 312 allow for evaluation of the function of the backflow prevention device 302 in the manner described above with respect to the first described embodiment. A test port valve 322 , 324 is attached to each test port 310 , 312 , respectively.
[0044] An inlet ball valve 326 and an outlet ball valve 328 make it possible to isolate the backflow prevention device 302 from the water system to which it is connected. The inlet ball valve 326 is mounted in a ball valve housing 330 which is mounted to the main body 304 , preferably by means of a threaded engagement. A test port 314 is provided on the ball valve housing 330 and defines a fluid flow passage 315 that is in fluid communication with a fluid flow passage 340 of the ball valve housing 330 . A test port valve 346 is attached to the test port 314 . The upstream end 348 of the ball valve housing 330 is configured for connection to a source of water, preferably using a threaded connection via internal threading 350 .
[0045] The outlet ball valve 328 is mounted in a second ball valve housing 352 which is mounted to the main body 304 , preferably by means of a threaded engagement. The downstream end 356 of the second ball valve housing 352 is configured for connection to a downstream system, preferably using a threaded connection via internal threading 366 .
[0046] Referring now to FIG. 10 , bridging portions 420 , 422 join the upstream portion 412 and the downstream portion 414 of the main body 304 and have tabs or shoulders 424 , 426 , respectively, projecting from their inner faces. The upstream portion 412 , the downstream portion 414 , and the two bridging portions 420 , 422 define an access passage 428 through the main body 304 . The access passage 428 facilitates the installation, removal, and manipulation of a removable cartridge 368 ( FIG. 9 ). Annular projections 430 , 432 extend into the access passage 428 from the upstream portion 412 and downstream portion 414 , respectively, of the main body 304 . Each annular projection defines an outward facing annular groove 434 , 436 , respectively.
[0047] As illustrated in FIGS. 11-12 , the removable cartridge 368 is designed to be easily mounted in the main body 304 . The removable cartridge 368 comprises a central cartridge body 370 and a collar 372 . The collar can be rotated from an extended position ( FIG. 11 ) for securing the cartridge 368 in the main body 304 to a retracted position ( FIG. 12 ) to release the cartridge 368 from the main body 304 for removal or installation.
[0048] Referring now to FIGS. 9 and 13 , the central cartridge body 370 defines a fluid flow passage 374 . A test port 316 is in fluid communication with the fluid flow passage 374 of the central cartridge body 370 via a test port channel 376 . A test port valve 378 is attached to the test port 316 . The upstream end 380 of the central cartridge body 370 is configured to fit over the annular projection 430 ( FIG. 10 ) at the upstream portion 412 of the main body 304 . An o-ring 438 , held in place by the annular groove 434 in the outer surface of the annular projection 430 , provides for a watertight seal between the central cartridge body 370 and the main body 304 .
[0049] Two check valves 382 , 384 are disposed in series inside the central cartridge body 370 . O-rings 386 , 388 , held in place by annular grooves 387 , 389 , respectively, provide essentially watertight seals between the check valves 382 , 384 , respectively, and the central cartridge body 370 . An annular groove 390 near the downstream end of the central cartridge body 370 holds an o-ring 392 . External threading 394 on the central cartridge body 370 upstream of the annular groove 390 is configured to mate with internal threading 396 of the inside of the collar 372 . The o-ring 392 provides an essentially watertight seal between the central cartridge body 370 and the collar 372 downstream of the threading 394 . The downstream end 398 of the collar 372 is configured to fit over the annular projection 432 ( FIG. 10 ) on the downstream portion of the main body 304 , as illustrated in FIG. 11 . An o-ring 440 ( FIG. 9 ), held in place by an annular groove 436 ( FIG. 10 ) defined by the outer surface of the annular projection 432 , provides for a watertight seal between the collar 372 and the main body 304 when the collar 372 is in the extended position ( FIG. 11 ).
[0050] When the removable cartridge 368 is mounted in the main body 304 , with reference to FIGS. 11 and 12 , the upstream end 380 of the central cartridge body 370 slides snugly on to the annular projection 430 of the upstream portion 412 of the main body 304 , and the downstream end 398 of the collar 372 slides snugly on to the annular projection 432 of the downstream portion 414 of the main body 304 , effectively holding the removable cartridge 368 in place.
[0051] The outer surface of the collar 372 includes a plurality of equally spaced, longitudinally extending ribs 373 to aid in the rotation of the collar 372 , either manually or with a tool. When the collar is rotated in one direction, the threading 394 , 396 ( FIG. 13 ) causes the collar 372 to retract onto the central cartridge body 370 as depicted in FIG. 12 , thereby reducing the effective overall length of the removable cartridge 368 and facilitating its removal from the main body 304 .
[0052] FIG. 14 depicts an alternative configuration of a removable cartridge 500 . A central cartridge body 502 defines a fluid flow passage 504 . A test port 506 is in fluid communication with the fluid flow passage 504 via a test port channel 508 . The upstream end 510 of the central cartridge body 502 is configured to fit over the annular projection 430 ( FIG. 10 ) on the upstream portion 412 of the main body 304 .
[0053] Two check valves 512 , 514 , an o-ring 516 , and a collar 518 are configured as described above for the second alternative embodiment of the removable cartridge 368 . The central cartridge body 502 further includes a relief valve docking station 520 . A relief channel 522 in the central cartridge body 502 provides fluid communication between the fluid flow path 504 through the central cartridge body 502 in the region between the two check valves 512 , 514 and the relief valve docking station 520 . One or more supply pressure channels 532 provide water at supply pressure from fluid flow path 504 upstream of the first check valve 512 to the relief valve docking station 520 .
[0054] The relief valve docking station 520 mates with a relief valve 210 ( FIG. 6 ) mounted in a relief valve cap 220 ( FIG. 6 ) as described above in relation to the first alternative embodiment of the backflow prevention device. The relief valve components are as described above and depicted in FIG. 8 .
[0055] The foregoing relates to preferred exemplary embodiments of the invention. It is understood that other embodiments and variants are possible which lie within the spirit and scope of the invention as set forth in the following claims. | A backflow prevention device includes a main body holding a removable cartridge. The removable cartridge houses two independently acting check valves and, optionally, a relief valve. A first portion of the cartridge may be retracted into a second portion of the cartridge, thereby reducing the overall length of the cartridge and facilitating the removal of the cartridge from the main body without the need to remove the backflow prevention device from a water supply system. The relief valve is contained in a removable cartridge. Each check valve may have a self cleaning plunger bore comprising at least one spiral groove. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
The document is a non-provisional patent application claiming priority to, and the benefit of, U.S. Provisional Patent Application Ser. No. 61/830,623; filed Jun. 3, 2013, also entitled “Purification Apparatus, System, and Method”, and U.S. patent application Ser. No. 14/295,263; filed Jun. 3, 2014; yet again, also entitled “Purification Apparatus, System, and Method” which claim priority to the provisional already mention and which are both herein incorporated by reference in their entirety for all purposes.
TECHNICAL FIELD
The present disclosure relates to “green” or “eco-friendly” (ecologically-friendly) technologies for purifying water. More specifically, the present disclosure relates to green technologies for purifying water in the field. Even more specifically, the present disclosure relates to green technologies for purifying surface water in the field.
BACKGROUND
Many related art technologies are currently utilized for purifying water. One of the greatest challenges facing humankind is the ability to treat, purify, and render water usable and/or potable in many distinct and different regions of the globe. Increasingly, these challenges are addressed by methods of treating water with biological materials, such as plant materials, that may involve natural and organic processes to accomplish this objective. These methods often require specialized tools, such as “laminae,” laminate, or laminated mats, to insure that the biological materials, such as plant materials, therein grow as well as thrive. Additionally, the laminae mat insures that the roots and other “active” parts of a plant or other biological material, being used in organic processes, are applied to the water source in a manner such that the filtration occurs with maximum efficiency. Related art laminae mats or other floating “tools” that are not homogeneous, e.g., having differing characteristics, result in less optimal growth and inefficient filtration. These challenges in the related art are exacerbated by the absence of adequate tools for applying such biological approaches to water filtration.
For example, many of the laminae mats available in the market today involve three elements: the supports, the cup positioners, and the receiving cups. These three elements often have different measurements and characteristics and are, therefore, separately fabricated, thereby requiring additional assembly during manufacturing, and thereby adding both cost and complexity to the process. Also, related art technologies require various connections to be made between a plethora of elements, thereby compromising structural integrity and adding undue complexity. Furthermore, many of these related art assemblies involve the use of undue amounts of material in their manufacture, thereby rendering these related art assemblies overly heavy, overly voluminous, and overly expensive, especially in relation to large-scale operation markets where these related art assemblies are cost-prohibitive. Finally, many of the related art assemblies that are currently available have noncompliant dimensions in relation to standard shipping sizes, e.g., standard shipping sizes that are outlined by the European Union for pallets, thereby rendering packaging and shipping an inefficient and expensive operation.
While these background examples may relate to water purification technologies in general, they fail to disclose a simple, modular, low density structure, having evenly distributed substructures for which macrophyte plants are disposable in order to permit adequate growth, that can be sequentially fabricated without leaving any gaps or uncovered areas. As such, a long-felt need has been experienced in the related art for a large-scale “organic” laminae mat, adaptable for floating on a surface of water to be treated and/or purified, wherein the large-scale “organic” laminae mat is an integrated structure, having sufficient structural integrity, is compliant with standard packaging and shipping guidelines, is both manufacturable and distributable at a low cost.
SUMMARY
In addressing many of the problems experienced in the related art, such as those relating to conventional laminae mats, the present disclosure generally involves an purification apparatus as well as its corresponding purification system and methods of fabrication and use, comprising a planar structure, such as a “mat” or “tool,” e.g., a laminae mat, a large-scale “organic” laminae mat, a microbial mat, or a floating “tool,” adaptable for floating on a surface of water to be treated and/or purified, wherein the large-scale “organic” laminae mat is an integrated structure, having sufficient structural integrity, is compliant with standard packaging and shipping guidelines, is both manufacturable and distributable at a low cost.
The present disclosure further involves a purification apparatus, comprising a planar structure, wherein the planar structure is disposable on a surface of a fluid body, e.g., a water body, and wherein the planar structure is homogeneous, e.g., the characteristics of the planar structure, as fully extended over the water surface, are homogeneous. In order to float well, the present disclosure contemplates a planar structure comprising materials, having a density in a range that is less than that of a given fluid, e.g., water, salt water, or fresh water, such that, even when plant or other biological material is added to the planar structure, the planar structure does not sink, but remains fully buoyant.
Preferably, since bodies of water differ in size and shape, e.g., in plan-form area, the present disclosure further contemplates a planar structure that is conducive for fabrication in a variety of corresponding sizes and shapes. To achieve this flexibility in fabrication, the planar structure comprises a plurality of subunits, whereby configuration of the final size and/or shape of the planar structure, as circumscribed by the needs of a given intervention or purification plan, is sufficiently flexible.
Further, the present disclosure encompasses a planar structure, wherein the plurality of subunits accommodate small seedlings of macrophyte plants in a manner such that the seedlings remain stable despite changing environmental conditions, that an appropriate separation exists between each subunit of the plurality of subunits and for avoiding undue impediment, thereby for facilitating root-growth, that the plurality of subunits cover a maximum surface area of the water for increasing filtration, and that any damaged plants or seedlings can be removed without undue interference from other plants and seedlings.
Furthermore, the purification apparatus can be assembled and disassembled without requiring any special tools or expertise, in accordance with the present disclosure. As such, the purification apparatus is installable anywhere in the world without requiring a large labor force, higher education, special training may, or special resources.
BRIEF DESCRIPTION OF THE DRAWING
The above, and other, aspects, features, and advantages of several embodiments of the present disclosure will be more apparent from the following Detailed Description as presented in conjunction with the following several figures of the Drawing.
FIG. 1A is a diagram illustrating a top perspective view of a purification system, such as a modular flotation system, comprising at least one purification apparatus, each at least one purification apparatus being a planar structure and comprising a frame and a plurality of subunits, each subunit comprising a receiving structure, in accordance with an embodiment of the present disclosure.
FIG. 1B is a diagram illustrating a bottom perspective view of a purification system, such as a modular flotation system, comprising at least one purification apparatus, each at least one purification apparatus being a planar structure and comprising a frame and a plurality of subunits, each subunit comprising a receiving structure, in accordance with an embodiment of the present disclosure.
FIG. 2 is a diagram illustrating a detailed top perspective view of a subunit of the plurality of subunits, the subunit comprising a receiving structure, such as a receiving cup, in accordance with an embodiment of the present disclosure.
FIG. 3A is a schematic diagram illustrating a detailed top view of a subunit comprising a receiving structure, such as a receiving cup, with a detailed partial view of a lower support portion of the receiving structure, in accordance with an embodiment of the present disclosure.
FIG. 3B is a schematic diagram illustrating a cross-sectional view of a subunit comprising a receiving structure, such as a receiving cup, in accordance with an embodiment of the present disclosure.
FIG. 3C is a schematic diagram illustrating a plurality of subunits, comprising two receiving structures, such as two receiving cups, being coupled together for facilitating stacking, in accordance with an embodiment of the present disclosure.
FIG. 3D is a schematic diagram illustrating a plurality of subunits, comprising two receiving structures, such as two receiving cups, being coupled together for facilitating stacking, in accordance with an embodiment of the present disclosure.
FIG. 4 is a diagram illustrating a detailed cut-away plan-form view of a purification apparatus, the purification apparatus being a planar structure and comprising a frame and a plurality of subunits, each subunit comprising a receiving structure, in accordance with an embodiment of the present disclosure.
FIG. 5A is a diagram illustrating a cross-sectional view of a fastener, such as a clip having a latch portion, for facilitating coupling of a plurality of purification apparatuses, in accordance with an embodiment of the present disclosure.
FIG. 5B is a diagram illustrating a cross-sectional view of a recess of a frame, for facilitating coupling of a plurality of purification apparatuses, in accordance with an embodiment of the present disclosure.
FIG. 6A is a diagram illustrating a plan-form view of a purification system, such as a modular flotation system, comprising a plurality of purification apparatuses, each purification apparatus being a planar structure and comprising a frame and a plurality of subunits, each subunit comprising a receiving structure, in accordance with an embodiment of the present disclosure.
FIG. 6B is a diagram illustrating a top perspective view of a purification system, such as a modular flotation system, comprising a plurality of purification apparatuses, each at least one purification apparatus being a planar structure and comprising a frame and a plurality of subunits, each subunit comprising a receiving structure, in accordance with an embodiment of the present disclosure.
Corresponding reference characters indicate corresponding components throughout the several figures of the Drawing. Elements in the several figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be emphasized relative to other elements for facilitating understanding of the various presently disclosed embodiments. Also, common, but well-understood, elements that are useful or necessary in commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present disclosure.
DETAILED DESCRIPTION
The following description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of exemplary embodiments. The scope of the disclosure should be determined with reference to the Claims. Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic that is described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
Further, the described features, structures, or characteristics of the present disclosure may be combined in any suitable manner in one or more embodiments. In the Detailed Description, numerous specific details are provided for a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the embodiments of the present disclosure can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the present disclosure.
In the several figures of the Drawing, the purification apparatus 100 is a generally planar structure, e.g., a mat, a laminae mat, floating surface lamina, or a microbial mat, provides an object-based technology that is implemented in an efficient manner and considers all of the variables affecting the purification apparatus' functionality, e.g., the generation and installation of floating surface laminae for the optimal treatment of bodies of water using living organisms, such as macrophyte plants, in accordance with the present disclosure.
In the preferred embodiment, the purification apparatus 100 comprises a polymer material, such as a low-density flexible polypropylene, and is manufacturable by way of injection molding technique, e.g., by a single injection cast, or by rapid prototyping, to integrally form a one-piece structure, the one-piece structure having the dimensional ranges and a variety of shapes as herein described. Understood is that, while the present invention provides such specifications for the benefit of full disclosure and best mode, any number of different shapes and sizes could be adopted, depending on a given living organism, such as a macrophyte or any other bioactive organism, wherein the size of the roots and the unique characteristics of the biological matter being applied to the surface of a fluid, such as water, aqueous solutions, aqueous mixtures, and other liquids, or other non-solid materials, such as sols or gels, are taken into consideration.
The purification apparatus 100 comprises a frame and a plurality of receiving structures 110 , e.g., cups or baskets, into which a living organism, such as seedlings of macrophyte plants, is insertable. The plurality of receiving structures 110 are formed and distributed throughout the planar structure of the purification apparatus 100 in a manner that, not only optimizes growth of the living organism, such as the macrophyte, but also facilitates stacking of each purification apparatus 100 , such as a mat, in relation to another purification apparatus 100 by providing registrability of one receiving structure or cup 110 in relation to another receiving structure or cup 110 , thereby providing a snug fit thereby clipping together. This configuration is optimal for shipping, handling, and overall transportation of the purification apparatus 100 . As such, transporting a plurality of the purification apparatuses 100 is possible at an accessible cost, being possible if the plurality of the purification apparatuses 100 are compliant with set standards, such as the European standard pallet plan-form (foot-print) size in a range of approximately 120 cm×approximately 80 cm, if the plurality of the purification apparatuses 100 are effectively stackable to facilitate the transport of the maximum number of units per unit of height, and if the plurality of the purification apparatuses 100 are light in weight. For water purification applications, the purification apparatus 100 comprises a material, such as a polymer, e.g., polypropylene, that is compatible with the biological environment, is non-contaminant, and is recyclable.
Referring to FIGS. 1A and 1B , these diagrams respectively illustrate top and bottom views of a purification apparatus 100 that facilitates suspension of bioactive living organisms, such as macrophyte plants, over a fluid body W, such as: a liquid, water, aqueous solution, aqueous mixture, liquid solution, liquid mixture, sols, or gels for naturally purifying the fluid body, in accordance with the present disclosure. The purification apparatus 100 comprises a plurality of receiving structures 110 , e.g., a cup or a basket, wherein each receiving structure 110 or plurality of receiving structures 110 is coupled with, e.g., integrally coupled with, at least one other receiving structure 110 by way of at least one connecting member 111 , such as connectors and basket-like structures. In addition, each purification apparatus 100 further comprises at least one fastener 130 , such as a bi-directional clip, laterally or peripherally disposed, wherein proper fastening thereof facilitates stackabilty as well as provides structural stability during transportation. While each receiving structure 110 is herein described with reference to its portions for clarity, understood is that, in a preferred embodiment, the purification apparatus 100 is formed as an integral one-piece structure, whereby additional assembly steps or the need for connectors, otherwise resulting in a structurally unstable configuration, is eliminated, and whereby the purification apparatus 100 provides has increased structural integrity.
Still referring to FIGS. 1A and 1B , the purification apparatus 100 can be optimally used to suspend a living organism, e.g., a bioactive organism, such as a macrophyte plant, on a fluid surface, such as a surface of water body (for example, a natural water body, such as fjords, portions of seas, portions of ocean, bays, lagoons, lakes, ponds, streams, creeks, rivers, or other natural waterways, or other pre-existing water body, such as artificially created water body, such as pools, reservoirs, flood controls), thereby providing a homogenous structure in the growth phase of the living organism. When the living organism reaches its natural size, e.g., through growth and intertwining of roots in the case of plants, the purification apparatus 100 provides an organism-based surface lamina which, when disposed in contact with dirty, contaminated, polluted fluids, e.g., dirty waters, or fluids otherwise in need of treatment, facilitates biological purification thereof. For example, large HAZMAT vats and HAZMAT reservoirs might benefit from this system. Many such vats and reservoirs are located in open space and “super-fund” sites in the U.S. As such, this system may be easily deployed to address other forms of pollution by using an appropriate bioactive organism for a given clean up.
Still referring to FIGS. 1A and 1B , the receiving structures 110 accommodate at least one living organism, such as a macrophyte plant, that will grow, thrive, and filter a fluid, such as water, by way of the living organism's structure, such as its roots in the case of plants, that grow distally through the bottom of the receiving structures 110 . In the preferred embodiment, the receiving structure 110 comprises a bio-degradable material, such as biodegradable starch based plastics that are environmentally-friendly and provides at least one opening 112 and at least one frangible portion 113 such that the roots can expand through the at least one opening 112 and even rupture the at least one frangible portion 113 if needed for optimal growth (See also FIG. 2 .).
Still referring to FIGS. 1A and 1B (See also FIG. 2 .), in a preferred embodiment, the purification apparatus 100 comprises at least one support portion, the at least one connecting member 111 comprising a polymer material, e.g., a low-density flexible polypropylene, or an olefin polymer material, e.g., a low-density polyethylene (LDPE), the at least one connecting member 111 being formed by way of a single-injection molding technique as an integrally formed one-piece configuration. LDPE is a polymer from the family of the olefin polymers; and LDPE is a thermoplastic polymer comprising repetitive units of ethylene. These or other LDPEs are polymers having a structure of highly branched chains. These, or similar materials, such as: composite materials, coated or encapsulated Styrofoam, and the like; having a density below 1.00, e.g., in a preferred range of approximately 0.92 to approximately 0.94, provide the purification apparatus 100 with sufficient buoyancy in relation to the fluid, such as water, and are encompassed by the present disclosure.
Still referring to FIGS. 1A and 1B , the purification apparatus 100 comprises a spatial distribution D for the receiving structures 110 , thereby providing a mathematically homogeneous mat, even independently of whether they are located at a periphery 140 of each purification apparatus 100 (See also FIG. 4 .). In the illustrated embodiment and by example only, the spatial distribution D follows a triangular pattern, such as an equilateral triangle, thereby facilitating a plurality of planting densities to meet the requirements of each, and any, intervention. However, any polygonal configuration may be formed by the connecting members 111 to effect a homogeneous mat and is also encompassed by the present disclosure.
Still referring to FIGS. 1A and 1B , the purification apparatus 100 comprises at least one fastener 130 ; the at least one fastener 130 may facilitate unidirectional, simple, fast, solid, quick-connect and disconnect, reversible assembly, storage, and distribution. By providing the purification apparatus 100 with a single, integrated, and flexible structure that can be manufactured by injection molding with use of a single injector, the apparatus 100 can interlock to create a solid laminae that is resistant to wind, waves, or other perturbations, e.g., caused by wildlife or seismic activity (in all directions of the surface plane) and can be anchored at the edge or periphery 140 in a very simple manner by way of the at least one fastener 130 , wherein the at least one fastener 130 is strategically disposed in a manner that facilitates and optimizes ease of connection, e.g., quick-connection and quick-disconnection, and minimizes any unusable space, e.g., space between any two purification apparatuses 100 is the purification system S of the present disclosure (See also FIG. 4 ).
Still referring to FIGS. 1A and 1B , in a preferred embodiment, each purification apparatus 100 comprises a frame F and a plurality of receiving structures 110 , e.g., at least sixteen (16) receiving structures 110 for receiving living organisms, such as seedlings, wherein each receiving structure 110 of the plurality of receiving structures 110 comprises a peripheral shape, such as: a triangular, square, polygonal, circular, curved or any combination of such shapes wherein the plurality of receiving structures 110 are disposed in relation to the at least one connecting member 111 to form a network of triangular structures, and wherein each receiving structure 110 of the plurality of receiving structures 110 comprises a node for facilitating bioactivity. The purification apparatus 100 in this configuration further comprises a plurality of fasteners 130 , e.g., four (4) fasteners 130 , that are easily registrable, and insertable, in relation to corresponding recesses of any other purification apparatus 100 , e.g., companion units. A purification system S comprises at least one purification apparatus 100 being fastened together by way of the at least one fastener 130 and corresponding recesses, thereby forming a solid and reinforced purification system S having high structural integrity, excellent buoyancy, and low weight.
Referring to FIG. 2 , a detailed top perspective view illustrates one embodiment of a receiving structure 110 , in accordance with the present disclosure. The receiving structure 110 may comprises at least three support portions, integrally formed, e.g., by single-injection molding. The at least three support portions may comprise an upper support portion 210 , e.g., having a hexagonal shape, at least one median support portion 220 coupled with the upper support portion 210 , e.g., being distributed and attached in relation to the perimeter of the upper support portion 210 , and a lower support portion 230 comprising at least one radial member 231 , wherein the major plane of the bottom support portion 230 is generally parallel to the major plane of the upper support portion 210 .
Still referring to FIG. 2 , the upper support portion 210 comprises a cross-section having at least one shape, such as: a triangular, square, polygonal, circular, curved or any combination of such shapes; and a cross-sectional area in a range of approximately 40 mm 2 to approximately 80 mm 2 in accordance with a preferred embodiment of the present disclosure.
Still referring to FIG. 2 , the at least one median support portion 220 comprises a cross-section having at least one shape, such as: a triangular, square, polygonal, circular, curved or any combination of such shapes and a cross-sectional area in a range of approximately 32 mm 2 to approximately 64 mm 2 , in accordance with a preferred embodiment of the present disclosure. Further, the at least one median support portion 220 is disposable or formable in a direction that is generally vertical or generally perpendicular in relation to the major plane of the upper support portion 210 .
Still referring to FIG. 2 , the lower support portion 230 comprises a cross-section having at least one shape, such as: a triangular, square, polygonal, circular, curved or any combination of such shapes; and a cross-sectional area in a range of approximately 25 mm 2 to approximately 50 mm 2 ′ in accordance with a preferred embodiment of the present disclosure. Further, the lower support portion 230 is disposable or formable in a direction that is generally horizontal or generally perpendicular in relation to the major axis of the at least one median support portion 220 and in a direction that is generally parallel to the major plane of the upper support portion 210 .
Referring to FIG. 3A , this schematic diagram illustrates a detailed top view of a subunit comprising a receiving structure 110 , such as a receiving cup, in accordance with an embodiment of the present disclosure. In a preferred embodiment, the upper support portion 210 comprises an inner dimension in a range of approximately 40 mm to approximately 80 mm. The at least one median support portion 220 comprises a width in a range of approximately 4 mm to approximately 2.5 mm, wherein the at least one median support portion 220 comprises a taper, e.g., narrowing from top to bottom. Reiterating, the at least one median support portion 220 , comprising a thicker width proximal to the upper support portion 210 , provides reinforcement. Further, the at least one median support portion 220 , comprising a narrow width proximal to the lower support portion 230 , provides significant space for growth of the living organism, e.g., a macrophyte plant, by providing ample room for the development of the living organism, e.g., its roots.
Still referring to FIG. 3A , the lower support portion 230 further comprises an opening 235 , e.g., a circular opening, having an inner dimension in a range of approximately 2.5 mm. The opening 235 is disposed at the center of the lower support portion 230 . This configuration provides an angle θ in a range of approximately 53 degrees between each at least one radial member 231 of the lower support portion 230 , whereby greater than approximately 87% of the lower support portion 230 is available for organism growth, such as root growth and root exposure. Additionally, by tapering the at least one median support portion 230 proximal to the lower support portion 230 , at least one other frangible portion 114 is thereby formed at such coupling between each at least one median support portion 230 and the lower support portion 230 , thereby providing less resistance and easier “breaking points” for the organism, e.g., the plant and roots in the event that the organism, e.g., the macrophyte plant, requires additional space.
Referring to FIG. 3B , this schematic diagram illustrates a vertical cross-section A-A of the receiving structure 110 , in accordance with an embodiment of the present disclosure. The width of the at least one median support portion 220 that is proximal to the upper support portion 210 comprises a range of approximately 1.24 mm to approximately 2.48 mm. while the width of the at least one median support portion 220 that is proximal to the lower support portion 230 comprises a range of approximately 0.75 mm to approximately 1.5 mm. The receiving structure 110 comprises a depth in a range of approximately 62 mm to approximately 124 mm, e.g., extending from the top of the upper support portion 210 to the bottom of the lower support portion 230 .
Referring to FIG. 3C , this schematic diagram illustrates two receiving structures 110 , such as two receiving cups, being coupled together, or disposed in relation to one another, for facilitating stacking, in accordance with an embodiment of the present disclosure. The two receiving structures 110 are shown as coupled for storage or shipment. The combination of the thickness of the receiving structure 110 and the angle subtended by the median support portion 220 from the top at the upper support portion 210 to the lower support portion 230 provide an optimal and beneficial coupling, thereby forming a spacing 340 in a range of approximately 0.4 mm to approximately 0.8 mm. The spacing 340 provides at least the following benefits: space saving when stacking together purification apparatuses 100 and sufficient tolerance between the receiving structures 110 for facilitating separation of the purification apparatuses 100 for deployment at the water site.
Referring to FIG. 4 , this diagram illustrates a detailed cut-away plan-form view of a purification apparatus 100 , comprising a frame F and a plurality of receiving structures 110 , such as a receiving cup, in accordance with an embodiment of the present disclosure. By example only, the dimensions of a single receiving structure 110 are shown in FIG. 4 . The single receiving structure 110 is disposed at a periphery of the purification apparatus 100 and is designated as an “edge unit,” wherein the single receiving structure 110 is coupled with at least one connecting member 111 , and wherein each at least one connecting member 111 may comprise a distinct dimension or different dimensions, e.g., a distinct length or different lengths. For example, the edge unit is coupled with a plurality of connecting members 111 , wherein at least two support connecting member 111 of the plurality of connecting members 111 comprise a length that is distinct from the remaining connecting members 111 . Accordingly, the at least two support members 111 (subunit disposed outboard) comprise a length in a range of approximately 50 mm to approximately 100 mm; and the remaining connecting members 111 (subunit disposed inboard) comprise a length in a range of approximately 112 mm to approximately 224 mm, by example only.
Still referring to FIG. 4 , the purification apparatus 100 further comprises at least one fastener 130 that is easily registrable, and insertable, in relation to corresponding recesses 131 of any other purification apparatus 100 , e.g., companion units. A purification system S comprises at least one purification apparatus 100 being fastened together by way of the at least one fastener 130 and corresponding recesses, thereby forming a solid and reinforced purification system S having high structural integrity, excellent buoyancy, and low weight. The frame F comprises any number of polygonal or curvilinear configurations. By example only, at least two configurations of the frame F are encompassed by the present disclosure.
Still referring to FIG. 4 and referring back to FIGS. 1A and 1B , the first configuration involves a given set of edges of the frame F being provided with at least one fastener 130 while the remaining set of edges are provided with at least one recess 131 , wherein the at least one fastener 130 of a frame F of one purification apparatus 100 can be correspondingly coupled with the at least one recess 131 of a frame F of another purification apparatus 100 , thereby facilitating coupling of one purification apparatus 100 to another purification apparatus 100 during deployment to form the purification system S. In addition, the frame F comprises at least one set of edges having a shape being correspondingly complementary to the remaining set of edges such that a plurality of purification apparatuses 100 may be interlockingly, yet removably, disposed in relation to one another to form the purification system S.
Still referring to FIG. 4 , in a second configuration, the frame F is provided with at least one fastener 130 along a set of opposing edges while the remaining set of opposing edges are provided with at least one recess 131 , wherein the at least one fastener 130 of a frame F of one purification apparatus 100 can be correspondingly coupled with the at least one recess 131 of a frame F of another purification apparatus 100 , thereby facilitating coupling of one purification apparatus 100 to another purification apparatus 100 , e.g., during deployment to form the purification system S. In addition, the frame F, in this embodiment, comprises at least one set of edges having a shape being correspondingly complementary to the remaining set of edges such that a plurality of purification apparatuses 100 may be interlockingly, yet removably, disposed in relation to one another to form the purification system S.
Still referring to FIG. 4 , in the second configuration, some “edge units” are coupled to the frame F by a single connecting member 111 and other “edge units” are coupled to the frame F by three connecting members 111 . These complementary “edge units” couple with one another in a manner such that the top surface of one purification apparatus 100 couples with the bottom surface of another purification apparatus 100 . As discussed in relation to FIG. 3C , this second configuration facilitates use of all space, eliminates undue gaps or spaces that would otherwise lead to unusable receiving structures 110 .
Referring to FIGS. 5A and 5B , FIG. 5A illustrates a cross-sectional view of a fastener 130 , such as a clip, having a latch portion 132 ; and FIG. 5B illustrates a cross-sectional view of a recess 131 , wherein the fastener 130 is disposable in the recess 131 for coupling together a plurality of purification apparatuses 100 for forming the purification system S, in accordance with an embodiment of the present disclosure. For example, the fastener 130 comprises a clip having a latch portion 132 . The latch portion 132 includes a tongue portion 133 (of one purification apparatus 100 ) that couples with a corresponding tongue recess 134 of the recess 131 (of another purification apparatus 100 ). The fasteners 130 comprise rounded edges for facilitating coupling the purification apparatuses 100 without undue engineering or difficulty.
Referring to FIG. 6A , this diagram illustrates a plan-form view of a purification system S, such as a modular flotation system, comprising at least one purification apparatus 100 , being a generally planar structure, the at least one purification apparatus 100 comprising a frame F and a plurality of subunits, each subunit comprising a receiving structure 110 , in accordance with an embodiment of the present disclosure. As shown, the purification system S comprises a plurality of purification apparatuses 100 coupled together in this embodiment. The geometry of the frame F of each purification apparatus 100 provides a powerful, yet facile, approach to forming a purification system S that accommodates not only large fluid, e.g., water, bodies, but also provides the ability to dynamically cover any shape or type of fluid body W, e.g., water, body.
Referring to FIG. 6B , this a diagram illustrates a perspective view of a purification system S, such as a modular flotation system, comprising at least one purification apparatus 100 , being a generally planar structure, the at least one purification apparatus 100 comprising a frame F and a plurality of subunits, each subunit comprising a receiving structure 110 , in accordance with an embodiment of the present disclosure. As shown, the purification system S comprises a plurality of purification apparatuses 100 coupled together in this embodiment. The geometry of the frame F of each purification apparatus 100 provides a powerful, yet facile, approach to forming a purification system S that accommodates not only large fluid, e.g., water, bodies, but also provides the ability to dynamically cover any shape or type of fluid body W, e.g., water, body. This perspective view of the purification system S shows that manner in which the purification system S floats on the surface of a fluid body.
Noteworthy is that, although several preferred embodiments of this invention have been described in detail herein with reference to the accompanying drawings, it is understood that the invention is not limited to these precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope of spirit of the invention as defined in the appended claims. For example, although the receiving structure 110 is shown with specific measurements and dynamics, many different configurations are contemplated that could involve similar angles and benefits without fundamentally altering the benefits and advantages of the present disclosure.
Information as herein shown and described in detail is fully capable of attaining the above-described object of the present disclosure, the presently preferred embodiment of the present disclosure, and is, thus, representative of the subject matter that is broadly contemplated by the present disclosure. The scope of the present disclosure fully encompasses other embodiments which may become obvious to those skilled in the art, and is to be limited, accordingly, by nothing other than the appended claims, wherein any reference to an element being made in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” All structural and functional equivalents to the elements of the above described preferred embodiment and additional embodiments as regarded by those of ordinary skill in the art are hereby expressly incorporated by reference and are intended to be encompassed by the present claims.
Moreover, no requirement exists for a system or method to address each and every problem sought to be resolved by the present disclosure, for such to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. However, that various changes and modifications in form, material, work-piece, and fabrication material detail may be made, without departing from the spirit and scope of the present disclosure, as set forth in the appended claims, as may be apparent to those of ordinary skill in the art, are also encompassed by the present disclosure. | A water purification apparatus comprising an injection molded floating non-toxic, biodegradable, and recyclable polymer planar structures that are easily stackable, shippable, and connectable to as many companion units as the user desires; such apparatus further comprising many receiving structures made to accommodate plants without inhibiting them so that the user may create a film of plants over a toxic body of liquid for bioremediation purposes. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119 based on U.S. Provisional Patent Application No. 61/708,311, which was filed on Oct. 1, 2012, the subject matter of which is incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates in general to the field of stationary bicycles trainers. More particularly, the present invention relates to a mounting arrangement for a the resistance unit of a bicycle trainer, in which the bicycle is held stationarily in place. The resistance unit is located such that when in use traction is increased as the user applies more torque on the bicycle pedals.
[0004] 2. Discussion of the Related Art
[0005] There are several types of bicycle training systems that provide resistance and/or hold a bicycle in a stationary position. For instance, many stationary bicycle trainers have resistance devices located in front of the rear tire. Others feature resistance devices located behind the rear tire. One issue with many bicycle training devices is that a decrease in traction occurs as the user applies more torque on the bicycle pedals, thus increasing the rotational speed of the rear wheel. Such a reduction in traction is undesirable in that it adversely effects intended operation of the bicycle trainer and may result in slippage of the bicycle tire relative to the resistance unit.
[0006] What is needed, therefore, is a bicycle trainer device that allows for a bicycle to be engaged with a resistance unit in a manner that prevents slippage and replicates real world friction and inertia, such that a user can experience conditions more closely simulating an outdoor ride.
BRIEF DESCRIPTION OF THE INVENTION
[0007] By way of summary, the present invention is a bicycle trainer system featuring a mounting frame and a resistance unit, wherein the resistance unit is located behind the rear wheel of the mounted bicycle.
[0008] In accordance with a first aspect of the invention, the bicycle trainer includes a wheel support system with an adjustment and locking, device such that a driven wheel of the bicycle can be suspended. Different sized tires and bicycles can be accommodated by such a system. Once the bicycle is mounted, a user can exert a pedaling force identical to the pedaling force on the bicycle while outdoors or on a track. The bicycle trainer frame may be of the type that has four feet that remain in contact with the ground while in use.
[0009] The mounting frame includes a reverse-mounted resistance unit, which applies resistance to rotation of the bicycle wheel. The reverse resistance unit is pivotably connected to the frame of the bicycle trainer such that, in use, the reverse resistance unit moves in a tightening direction against the wheel of the bicycle.
[0010] An adjuster is included on the reverse resistance unit to increase or decrease the tightness of the reverse resistance unit by rotating a knob. The reverse resistance unit is located such that, when in use, traction and inertia are increased as the user applies more torque on the bicycle pedals to increase wheel speed. This ensures that the wheel of the bicycle does not slip and therefore provides a more realistic feel and experience during use.
[0011] These and other features and aspects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings It should be understood, however, that the following description, while indicating a representative embodiments of the present invention, is given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] A clear conception of the advantages and features constituting the present invention, and of the construction and operation of typical mechanisms provided with the present invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings accompanying and forming a part of this specification, wherein like reference numerals designate the same elements in the several views, and in which:
[0013] FIG. 1 is a rear side perspective view of one embodiment of a bicycle trainer incorporating the a reverse resistance unit mounting arrangement in accordance with the present invention;
[0014] FIG. 2 is a front side perspective view of the bicycle trainer with reverse resistance unit mounting arrangement as shown in FIG. 1 ;
[0015] FIG. 3 is a side elevation view of the bicycle trainer with reverse resistance unit mounting arrangement as shown in from FIGS. 1 and 2 : and
[0016] FIG. 4 is a section view taken along line 4 - 4 of FIG. 2 .
[0017] In describing the embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word connected, attached, or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Specific embodiments of the present invention will be described by the following non-limiting examples which will serve to illustrate various features of the invention, With reference to the drawing figures in which like reference numerals designate like parts throughout the disclosure, a representative embodiment of the present invention is a bicycle trainer 5 that allows for stationary training on a bicycle which may be a road or mountain bike or the like. The bicycle trainer 5 includes a frame 9 that supports the bicycle in a generally stationary position while a user exerts a pedaling effort to rotate a driven wheel 11 of the bicycle during a training session, in a manner as is generally known, in which the rotation of the driven wheel 11 is resisted by a resistance unit 13 that is arranged under a cover 14 and on the frame 9 , as is described in greater detail elsewhere herein. The resistance unit 13 operates in a known way and can be one of an electronic, magnetic, fluid, or airflow-type resistance units such as, for example, those incorporated into various ones of the POWERBEAM PRO, SUPERMAGNETO PRO, JETFLUID PRO, FLUID2, MAGNETO, and WIND series trainers available from CycleOps POWER of Madison. Wis.
[0019] Referring to FIGS. 1 and 2 , frame 9 is generally U-shaped and includes a lower segment 15 that is connected to a bar 17 that has a pair of rear feet 19 that engage the ground or other underlying support surface. A pair of side segments 21 extends from opposing ends of the lower segment 15 of the frame 9 . The side segments 21 extend angularly from the lower segment 15 and bar 17 . A space 23 is defined between the side segments 21 and in which the driven wheel 11 is arranged during use Legs 25 extend downwardly from upper ends 27 of the frame side segments 21 . Forward feet 29 are arranged at the lower ends 31 of the legs 25 and engage the ground or other underlying support surface. It is understood, however, that the frame of bicycle trainer 5 may have any other satisfactory configuration that supports the bicycle and the resistance unit 13 .
[0020] Still referring to FIGS. 1 and 2 , a wheel support system 33 is arranged toward an upper portion of the frame 9 for mounting the driven wheel 11 to the bicycle trainer 5 . Wheel support system 33 includes an adjustment device 35 and a locking device 37 that are arranged at the upper ends 27 of the frame side segments 21 . Adjustment device 35 includes a tube 39 that extends in a transverse direction with respect to the bicycle trainer 5 . The tube 39 has internal threads (not shown) and an adjustment screw 41 which threads into the threads of the tube 39 and a threaded lock ring 43 that is threaded and concentrically held on the adjustment screw 41 . In this way, the adjustment screw 41 can he turned out from or turned in the tube 39 and locked in place with the lock ring 43 , like a jamb nut, to fix an end 45 of the adjustment screw 41 which engages and supports an end of a skewer 47 ( FIG. 1 ) that extends through and supports a hub 49 ( FIG. 1 ) of the driven wheel 11 .
[0021] Still referring to FIGS. 1 and 2 , the locking device 37 of the wheel support system 33 includes a tube 51 that has a circumferential side wall 53 and a slot 55 that extends through the circumferential side wall 53 along a generally helical path. A pocket (not shown) extends from an inward end of the slot 55 that is closest to the driven wheel 11 and provides a recess in which a handle 59 that extends through the slot 55 can lock into to secure the handle 59 in a fixed position, in a bolt-action manner. The handle 59 is connected to a bolt tube 61 that is arranged concentrically within the circumferential side wall 53 so that the bolt tube 61 slides through a longitudinally extending opening of the tube 51 . The handle 59 and bolt tube 61 move in unison with each other so that moving the handle through the slot 55 toward the driven wheel 11 correspondingly moves the bolt tube 61 in the same direction so that it extends further beyond the tube 51 , toward the driven wheel. This allows for mounting the driven wheel 11 in a known manner by arranging the skewer 47 ( FIG. 1 ) between the adjustment screw 41 and bolt tube 61 and advancing the handle 59 through the slot 55 until it enters and is held in the pocket (not shown) at the inward end of the slot 55 , at which point the skewer 47 ( FIG. 1 ) is pinched between the adjustment screw 41 and the bolt tube 61 and the driven wheel 11 is in driving engagement with the resistance unit 13 . Again, it is understood that any other satisfactory arrangement may be employed for securing the bicycle wheel in place on the frame 9 .
[0022] Still referring to FIGS. 1 and 2 , the resistance unit 13 is supported by a supporting member secured to the frame 9 , which may be in the form of a hoop 63 that is generally U-shaped and is arranged generally parallel to the ground or other underlying support surface. Hoop 63 extends between and connects the frame side segments 21 to each other. The resistance unit 13 is supported by the hoop 63 in a manner that allows the resistance unit to move in a tightening direction toward and in a loosening direction away from the driven wheel 11 . Referring now to FIG. 3 , the resistance unit 13 is movable with respect to the frame 9 between a fully extended position, shown in phantom-dashed outline closer to the legs 25 and a fully retracted potion, shown in phantom-dashed outline further from the legs 25 .
[0023] Referring now to FIG. 4 , a hinge arrangement 65 interconnects the resistance unit 13 and the hoop 63 . The hinge arrangement 65 includes a hinge 67 and an adjuster 69 that cooperate with each other to locate the resistance unit 13 in a generally longitudinal direction within the bicycle trainer 5 ( FIG. 3 ). Hinge 67 includes a hinge arm 71 with an upper end 73 that has an opening 75 that concentrically holds the hoop 63 and is arranged so that the hinge arm 71 can pivot about the hoop 63 . In this way, a pivot axis 77 of the hinge 67 is defined longitudinally through the hoop 63 . A lower end 79 of the hinge arm 71 supports the resistance unit 13 so that a roller 81 of the resistance unit 13 can freely rotate as driven by its engagement with tire 83 that is mounted to a rim 85 of the driven wheel 11 .
[0024] Still referring to FIG. 4 , the adjuster 69 includes a plate 87 that extends generally parallel to the side segment(s) 21 and has a threaded bore 89 through which threaded stem 91 of a handle 93 extends. The threaded stem 91 of the handle 93 extends generally parallel to the hinge arm 71 and has a first end 95 to which a knob 97 is connected and a second end 99 that can rotate in unison with a block 101 that is connected to and moves the resistance unit 13 . As shown in FIG. 4 , this is done with a cylinder 103 that is captured in a pocket 105 of the block 101 while being rotatable within the pocket 105 . In this way, the adjuster 69 can be used to set the initial tightness of the resistance unit 13 by rotating the knob 97 in a first direction so that the threaded stem 91 advances through the plate 87 and the ball 103 moves longitudinally away from the plate 87 and pushes the block 101 , which forces the entire resistance unit 13 to pivot about the pivot axis 77 of the hinge 67 so as to move the roller 81 closer to the driven wheel 11 . The knob 97 is rotated in a second, opposite direction to move the resistance unit 13 in the opposite direction, away from the driven wheel 11 so as to loosen the resistance unit 13 .
[0025] Still referring to FIG. 4 , the hinge arrangement 65 allows the resistance unit 13 to automatically bias in its tightening direction when a driving torque of the driven wheel 11 is applied or increased so as to dynamically increase traction of the driven wheel 11 against the roller 81 . That is, because the driven wheel 11 rotates in its use direction shown as arrow 105 , the driven wheel 11 applies a rotational force to the roller 81 that extends in a direction of a tangent line shown as arrow 107 from a contact area 109 defined at the interface of the roller 81 and tire 83 . Since the pivot axis 77 is positioned above and behind the contact area 109 , the vector of the rotational force tangent line 107 causes the force to push the hinge arm 71 to pivot about the pivot axis 77 in the tightening direction of the resistance unit 13 toward the wheel 11 in an automatic dynamic biasing movement represented by arrow 111 . This increases the normal force 112 at the interface of the roller 81 and tire 83 so as to further tighten an engagement between the roller 81 and tire 83 at the contact area 109 . In this way, as a user pedals faster or otherwise increases driving speed of the driven wheel 11 , the reactionary forces experienced by the resistance unit 13 bias the resistance unit 13 toward driven wheel 11 so as to increase traction through an increase in the normal force 112 at the interface of the roller 81 and tire 83 and thus at the contact area 109 . In this manner, it is insured that there is no slippage between wheel 11 and resistance unit 13 , which provides a more realistic ride feel during use of trainer 5 .
[0026] While a specific embodiment of the tightening and adjustment arrangement are shown for illustrative purposes, it is understood that any other satisfactory mechanism may be employed for selectively moving resistance unit 13 toward and away from the bicycle wheel 11 .
[0027] Various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention. | A bicycle trainer includes a reverse resistance unit mounting arrangement that is configured to increase traction between a bicycle wheel and a resistance unit upon an increase in the speed of rotation of the wheel. The reverse resistance unit mounting arrangement is configured to mount the resistance unit in a suspension-type manner and has an actuator that initially positions the resistance unit against the bicycle wheel. The reverse resistance unit mounting arrangement tends to pivot the resistance unit against the bicycle wheel during use, to automatically bias the wheel toward the resistance unit to prevent slippage between the bicycle tire and the roller of the resistance unit. | 0 |
BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a pattern selecting system of an electronic sewing machine, in which the normally and frequently used pattern selecting switches may be utilized by operation of a separate switch to select patterns which are very specific and not so frequently selected.
The stitch patterns of the electronic sewing machine are stored as a pattern information in an electronic memory element. Now such a memory element has been made so small by the improvement of a semi-conductor integration technique. Although the memory element is small, it may store a considerable amount of stitch data as compared with the mechanical memory such as cams. In the electronic sewing machine, the pattern selection is performed by distinguishing electric signals for selectively calling up the stored data. That is, the pattern selection in general requires the pattern selecting switches which are each operated in response to desired patterns, the pattern indicating parts and the selection indicating lamps each lights to indicate the selection of a pattern. Such pattern selection requirements will be increased more as the electronic sewing machine stores many patterns. However, a space of a sewing machine is limited for mounting the pattern selecting system of so many selection requirements. If so many patterns are prepared on the sewing machine, each of the members necessary to the selection should be made small accordingly. As a result, the pattern selecting operation becomes difficult. If we consider the necessity of the patterns to be stitched, it is found out that some are frequently employed and some are seldom employed.
In view of these circumstances involved in the use frequency, the present invention has been devised to provide a pattern selecting system suited to the electronic sewing machine which stores a lot of the patterns.
Therefore, according to the invention, the frequently used patterns are provided as a first group of patterns on the front panel of the sewing machine each in association with the corresponding pattern selecting switches and indicating lamps. On the other hand, the patterns not so frequently used are provided as a second group of patterns in a normally concealed part such as on the underside of the top plate of the sewing machine. For selecting such a second group of patterns, a separate change-over switch is provided, which is operated to change the switches for the first group of patterns to function for selecting the second group of patterns.
The other features and advantages of the invention will be apparent from the following description of the invention in reference to a preferred embodiment as shown in the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a sewing machine provided with a pattern selecting system of the invention,
FIG. 2 is an enlarged view of a main part of the invention,
FIG. 3 is an enlarged view of the under side of the top plate of the sewing machine of the invention,
FIG. 4 is an electric control block diagram of the invention, and,
FIG. 5 is a flow chart of the control diagram.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be explained in reference to the attached drawings. In reference to FIG. 1, the reference numerals 1 to 10 are pattern selecting push buttons, 1' to 10' are pattern indications in the first group which are to be frequently used. The reference numerals 1" to 10" are selection indicating lamps of light emitting diodes which are each arranged inwardly of the pattern indications 1' to 10' to light each of the latter when a pattern of the first group is selected. The reference numerals 11 and 12 are number-indicating parts of 1 segment for the patterns of a second group which are not so frequently used. Numeral 13 is a switch which is pushed to change the function of the pattern selecting switches 1 to 10. In a condition that the switch 13 is not pushed and is in the first position, the buttons 1 to 10 serve for selecting the first group of patterns, and the selected patterns are indicated on the indicating parts 1' to 10' by the indicating lamps 1" to 10".
When the switch 13 is pushed and in the second position, the patterns of the second group are selected with two figures indicated in the indicating parts 11, 12 by continuously operating any of the switch buttons having numbers 0 to 9 as shown in FIG. 2. In this case, when the switch 13 is pushed, the top plate 14 of the sewing machine is released and is opened by a spring (not shown) as shown in FIG. 1. On the under side 15 of the top plate, the patterns of the second group and the necessary explanations thereof are provided in the form as shown in FIG. 3.
A next reference will be made to a selecting control of the patterns of the first group by the control block diagram in FIG. 4. A micro-computer composed of a central processing unit CPU, a read-only-memory ROM, a random-access-memory RAM and an input-output port I/O, receives a signal issued from the pulse generator in synchronism with rotation of the upper shaft of the sewing machine and a signal from the pattern selecting part including the pattern selecting push buttons 1 to 10, and gives a signal to a selected one of the pattern selection indicating lamps 1" to 10" and gives a stitch signal to the electric bight and feed control devices of the sewing machine per rotation of the sewing machine in accordance to a program stored in the memory ROM as shown in the flow chart in FIG. 5, thereby to form the stitches of the selected pattern.
The selection of the patterns of the first and second groups will be explained in reference to FIGS. 4 and 5. Selection of the first group of patterns can be carried out by pushing the push buttons 1 to 10. That is, if one of the push buttons 1 to 10 is pushed in a condition that the switch 13 is not pushed and is in the first position, the pattern selecting signal is read into the random-access-memory RAM of the micro-computer via the latch circuit 4 to change the value of M1 register for controlling the 7-segment indicating device 11 of said memory, and also change the value of M2 register for controlling the indicating device 12, and also change the value of M3 register for controlling the indicating lamps 1" to 10", thereby to select one of the patterns 1' to 10', and light the corresponding one of the indicating lamps 1" to 10" via the decoder, and thus the selected pattern is produced when the sewing machine is driven by operating the controller (not shown). A reference letter "N" in the flow chart is a discriminating signal stored in the memory RAM to discriminate figures of the 7-segment indications 11, 12 in the selection of the second group of patterns.
The selection of the second group of patterns is as follows; the switch 13 is pushed into the second position and the patterns and the corresponding numbers in all two figures are known from the pattern indicating table on the under side 15 of the top plate 14. If a desired pattern has a number 8 8, the pattern can be selected by pushing twice the push button 8 of the push buttons 0 to 9. In this case, if the push button 8 is pushed, the number is indicated in the indicating part 12, and the signal N becomes 1 and then if the push button is pushed once more, the number is indicated in the indicating part and the signal N becomes 2, since in the meantime the contents of M1 register, M2 register and M3 register are replaced. In this case, the lamps 1" to 10" do not light. Thus the program is carried out for stitching the selected pattern of the second group. | A pattern selecting system is disclosed in which a single set of push buttons is utilized to select a first group of patterns each of which corresponds to a particular push button and a second group of patterns indicated by a series of two figure numbers. | 3 |
BACKGROUND OF THE INVENTION
This invention relates to new and useful improvements in a shaft re-greasing hub and is particularly adaptable for greasing wheel bearings.
Wheel hubs, particularly truck and trailer hubs, are difficult and time consuming to pack with grease. It usually requires removal of the hub cap, the wheel or dual wheels, the brake drum or rotor, the hub, the inner lubrication seal, and the bearings.
DESCRIPTION OF BACKGROUND ART
Currently, the industry favors oil for lubricating wheel hubs since oil provides two advantages over the earlier procedure of packing with grease. These advantages are: 1) The oil level in the hub can be easily maintained to assure that the bearing is in fact lubricated and 2) Slightly improved cold weather fuel mileage is obtained due to less stiffness of the oil. This presently popular system does not, however, have a service life equal or greater than the service life of modern extended life braking components. Vehicle supplementary braking systems such as engine brakes further extend brake life. Any seal failure or seepage wets the brake and can lead to a citation, and the necessity of immediate repair. Furthermore, oil leakage may result in bearing failure, a brake failure or even a brake and wheel fire. Consequently, wheel end maintenance with oil as to the lubricant is very costly in the long run and a preventive maintenance program is difficult to pursue in which the full service life of all the related components can be utilized as it becomes necessary to either perform re-work or to prematurely replace components.
Devices have heretofore been patented to ease the task of greasing shaft bearings, including wheel bearings. For example, U.S. Pat. No. 4,636,007 relates to a hub design seeking to permit the application of grease directly at each of the inner and outer bearings. Grease ports are accessible from the front of the wheel and channel grease to the inner and outer bearings. Structure shown in this patent has inherent disadvantages, one disadvantage being that the hub permits re-packing the hub cavity with grease flow to and about the bearings but not axially through the bearings so that an efficient and complete purging of old grease cannot be accomplished as well as re-greasing. Another disadvantage of U.S. Pat. No. 4,636,007 is that the inner bearing chamber is not vented whereby when the warm hub, warm grease and other components are immersed in water, the water, being cooler, creates a vacuum. This vacuum draws water through the inner grease seal which of course is trapped within the wheel to cause rust, interference with lubrication, and the expelling of grease when warm.
U.S. Pat. No. 2,249,501 relates to supporting structures for rotating shafts and to lubricating systems for such supports. It is comprised of an oil reservoir system and a lubricant metering system to restrict and meter gravity fed oil to an anti-friction bearing. The used oil is then collected in a chamber beneath the bearing. This system requires continual monitoring.
U.S. Pat. No. 3,903,992 shows a device for greasing a single bearing on a shaft during shaft rotation. A grease slinger plate with a canted vein urges grease through the bearing and out the bearing housing cap discharge opening, while maintaining a breathing space in the non-vented stationary bearing housing.
U.S. Pat. No. 4,988,218 is directed to oil lubrication of bearings when oil is pumped and maintained under pressure through the axial shaft or hub face and through the bearings to the rear of the hub.
SUMMARY OF THE INVENTION
Recent developments in modern wheel bearing greases, particularly heavy duty synthetic greases, are found to have considerably less cold weather rolling resistance problems as compared to earlier wheel bearing greases, and applicant, according to an important object of the present invention, has taken advantage of such developments in grease to provide a specially designed hub with grease fittings and grease raceways such that efficient and fast packing of the wheel bearings can be accomplished from the exterior, namely, from the front, without wheel, brake, or hub removal.
Another object is to provide a hub that is vented and non-pressurized during operation with a wheel, that stops seepage of lubricant through seals, protecting brake components while maintaining the hub bearing in a grease raceway providing optimum lubrication.
Still another object of the invention is that the greasing structure permits the bearings to be re-greased and the old grease examined for foreign material during scheduled preventative maintenance servicing. It is estimated that use of the present hub may permit the industry to save 75% of present related costs.
The invention will be better understood and additional objects and advantages will become apparent from the following description taken in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view of the present hub and a spindle mounting thereof.
FIG. 2 is a view similar to FIG. 1 but including special servicing fittings used with the invention in repacking the hub wheel bearings from the exterior without removal of the wheel.
FIG. 3 is a longitudinal sectional view of a hub using the concept of the invention as applied to a drive axle spindle.
FIG. 4 is a fragmentary longitudinal sectional view of structure similar to FIG. 3 but showing an alternate drive axle sealing arrangement, and
FIG. 5 is a view similar to FIG. 1 but showing a modified positioning of one of the grease passageways in the hub.
DESCRIPTION OF PREFERRED EMBODIMENTS
With particular reference to the drawings, FIG. 1 shows the working form of a first embodiment of the present hub in a fully greased condition. It comprises a hub 10 having an outer end cap 12 with an O-ring seal 14 therebetween. The outer end of the cap has an opening 15 for removably receiving a plug 16 with an O-ring seal 18 at the opening. Plug 16 has a small axial vent port 19 and the inner surface thereof has a deepened concavity recess 16a. The numeral 20 designates the usual spindle and the numeral 22 designates the usual end nut retaining assembly.
The present hub encloses the usual inner and outer bearings 24 and 24a, respectively, and includes an interior annular seal 26 about the spindle 20 between the inner and outer bearings. The seal is tapered similar to the spindle and has a central bore 26a of reduced diameter and radial dimension to provide a circumferential grease purging passage 28 around the spindle 20. The outer surface of this seal has engagement against the inner bore of the hub body 10 and the ends thereof have longitudinal extensions 30 with edge engagement against outer raceways 32 and 32a of bearings 24 and 24a, respectively. Extensions 30 create circumferential inner and outer grooves 34 and 34a around the inner surfaces of bearings 24 and 24a, respectively. The inner surface or bore 26a of the seal has multiple annular grooves 36 for the storage of additional grease. Interior annular seal 26 has one outer circumferential groove 38 that communicates with a purging port 40 in the hub body 10 and communicates with radial ports 42 in annular seal 26 in turn opening to grease pathway 28. The numeral 44 designates the usual lubricant seal at the inner end of the hub. The present hub is designed to leave a circumferential greasing area 46 between oil seal 44 and the inner bearing 24.
In running operation of the hub, a sealing plug 48 and an O-ring 50 seal port 40. The end cap 12 has a recess 52 on its inner face which cooperates with the recess 16a in the end cap plug 16 to form an enlarged inner cavity 52a that communicates with the front of the outer bearing 24a.
A first grease fitting 54 is mounted in the outer end cap 12 and communicates with a port or passageway 56 which leads to inner cavity 52a. A second grease fitting 58 is also mounted in end cap 12 and communicates with an elongated port or passageway 60 and junction 70 that lead to the circumferential area 46 between the inner bearing 24 and seal 44. Port 60 is sealed by O-ring 62 at the mating surfaces of hub body 10 and end cap 12. Grease fittings 54 and 58 are recessed in the end cap 12 for protection.
REGREASING OPERATION
In the function of applying new grease, reference is made to FIG. 2. First, an outer surface sealing plug 64 is installed in place of the hub end cap vent plug 16. Plug 64 is not vented and seals cavity 52a. It is fully threaded and driven inwardly in abutting relation against the end of the spindle. The plug 64 fills some of the recess 52 and saves grease in the process of greasing. Plug 48 in outlet 40 is removed and a purging grease collection tube 68 is fitted in place of plug 48. Thereupon, a grease gun is connected to one of the fittings 54 or 58, for example, the fitting 54. Upon pressured insertion of grease through this fitting, grease fills cavity 52a at the outer bearing 24a. New grease flows longitudinally or in other words in an axial direction through outer bearing 24a, completely flowing through the bearing and displacing old grease. Grease then gathers in end groove 34a on interior seal 26, then flows through passage 28 where the used grease flows through radial ports 42 to collection groove 38 and is expelled from the hub by way of purging port 40 and servicing purging tool 68. Thereupon, the other grease fitting 58 is utilized to direct grease through the longitudinal port 60 to circumferential area 46 at the rear of the inner bearing 24. New grease flows longitudinally or in other words in an axial direction through bearing 24, into end groove 34 in seal 26, through passageway 28 and out radial ports 42 to the purging tool. In accordance with varying applications, the hub may have multiple sets of inner and outer greasing fittings 54 and 58 and respective longitudinal ports. Port 60 may branch into multiple ports at junction 70 to uniformly communicate with circumferential greasing space 46. With the insertion of grease through the end cap grease fittings 54 and 58, grease packs both inner and outer bearings individually with new grease. Grooves 34 and 34a are packed with grease as are the portions of cavity 52a around the service sealing plug 64, the greasing areas 46 behind bearings 24, grease passageway 28, and annular grooves 36 in the seal 26.
After packing the above areas, the sealing plug 64 is removed and the end cap vented plug 16 is installed. Center recess or void 16a becomes a vented expansion area. Purge tool 68 is removed and plug 48 is reinstalled.
In operation, centrifugal force from rotation of the hub maintains grease in outer radial areas of cavity 52a and in inner area 46 against their respective bearings. Also maintained in usage is end cap interior expansion area 16a that assures fully vented non-pressured lubrication to minimize seepage or failure of inner seal 44. Furthermore, in the event of bearing failure, a catastrophic type failure is reduced to a much less expensive repair by virtue of hub interior seal 26 functioning as a fail-safe sleeve bearing for the spindle and hub. This reduces the risk of hub-wheel-tire to axle separation. The annular grooves 36 in the seal 26 hold lubricant to further protect from further damage a fail/safe operation. The design of the hub maintains the bearing in a grease raceway free of voids and contaminants in a vented non-pressured hub, thusly maintaining the integrity of lubrication and inner grease seals for extended service life and reduced wheel end maintenance costs.
FIG. 3 shows an embodiment of the present invention as applied to a drive axle configuration. In this structure the drive axle 76 comprises a hub 10' removably connected to an end flange 78 of the drive axle with an O-ring seal 80 therebetween. The numeral 82 designates the usual annular drive axle housing spindle that forms with drive axle 76 a venting passageway to the drive axle housing, and the numeral 84 designates the end nut retaining assembly. Novel features of the instant invention are substantially the same in the embodiment of FIG. 3 as in the embodiment of FIG. 1 except that greasing portions of FIG. 3 are associated with the drive axle flange 78 and a drive axle housing spindle 82 instead of hub outer end cap 12 and spindle 20.
In this second form, the hub 10' encloses inner and outer bearings 24' and 24a', respectively, and provides an interior seal 26' about the spindle 82 between the inner and outer bearings. The seal has a central bore 26a' of tapered configuration and radial dimension to provide a circumferential grease passage 28' around the spindle 82. The outer surface of this seal has circumferential engagement against the bore in hub body 10' and the inner end thereof has radial extension 30' that engages the inner bearing outer raceway 32', creating a radial end groove 34' around the inner surface of inner bearing 24'. The inner conical surface of seal 26' has multiple annular grooves 36'. The outer edge of seal 26' communicates with a circumferential area 88 that in turn communicates with the inner face of outer bearing 24a'. Circumferential area 88 also communicates with grease passageway 28' as well with purging port 40' in hub body 10' and internal vent port 90. The numeral 44' designates the lubricant seal between the inner end of the hub and the spindle with a circumferential greasing area 46' between the lubricant seal 44' and the inner bearing 24'. The axial flange 78 encloses cavity 52a' that communicates between this flange and the front of the outer bearing 24a'.
A first grease fitting 54' is mounted on the face of drive axle flange 78 and leads to area 52' by means of a port or passageway 56'. A second grease fitting 58' is also mounted in the drive axle flange and communicates with an elongated port or passageway 60' that leads to the circumferential space 46' behind the inner bearing 24'. Port 60' is sealed by O-ring 62' at the mating surfaces of hub body 10' and the drive axle flange 78.
In the function of applying new grease, plug 48' that is mounted in outlet port 40' in operative running of the bearing is removed and combined purge grease collection and internal vent sealing tool 68' is fitted in the purging port 40'. The purge tool 68' for this embodiment includes a spring pressed plunger 91 that is in direct line with port 90 for sealing this port when the tool is inserted for regreasing. At the same time, tool 68' allows purging of old grease through a hollow body structure thereof. Thereupon, a grease gun is connected to one of the fittings 54' or 58', for example, the fitting 54'. Upon pressured insertion of grease through this fitting, such grease fills cavity 52a' at the outer bearing 24a'. Circumferential cavity 52a' is sealed between the inner bore 92 of the drive axle housing spindle 82 and the drive axle shaft by a sealing assembly 94. An alternate spindle bore 92' and axle shaft double seal 94' are depicted in FIG. 4. New grease flows through bearing 24a' displacing old grease. Grease gathers in circumferential area 88 and is expelled from the hub by way of purging port 40' and servicing purge tool 68'. Thereupon the other grease fitting 58' is utilized to direct grease through the longitudinal passageway 60' to circumferential area 46' at the rear of the inner bearing 24'. In accordance with varying applications, the hub may have multiple sets of inner and outer greasing fittings 54' and 58' and respective longitudinal passages. Passage 60' may branch into multiple ports at junction 70' to more uniformly communicate with circumferential greasing space 46'. With the insertion of grease through the flange grease fittings, grease will fill end circumferential areas 52a' and 46', pack both inner and outer bearings in an axial direction with new grease, fill circumferential area 88 and groove 34' in seal 26' with new grease and force old grease and contaminants out the purging port 40'. This purged grease can be collected and examined.
Thereupon the purge and vent sealing tool 68' is removed and purging port plug 48' reinstalled. The hub is now vented through the interior axle housing by way of vent port 90 and the bearings are maintained In circumferential grease raceways by hub interior seal 26'.
In rotative operation of the hubs hereof, centrifugal force maintains both bearings in circumferential grease raceways created for the inner and outer bearings. Also maintained in usage is hub interior vent 90 assuring full vented non-pressurized lubrication to minimize seepage or failure at seal 44'. Furthermore, as in the FIG. 1 embodiment, in the event of bearing failure, a catastrophic situation is reduced to a much less expensive repair by virture of hub interior seal 26' functioning as a fail safe sleeve bearing and saving the spindle and hub, while reducing the risk of hub-wheel-tire to axle separation. Also, hub interior seal inner annular radial grooves 36' hold lubricant to further assist in a fail-safe operation. Also, as in the FIG. 1 embodiment, the design of FIG. 3 maintains the bearing in a grease raceway free of voids and contaminants in a vented non pressurized hub, thus maintaining the integrity of lubrication and seals for extended service life and reduced wheel and maintenance costs.
FIG. 5 shows another embodiment of the invention. In this embodiment, the grease fitting 58" to the inner bearing is mounted in a recessed portion of the hub 10 which is close to the wheel flange and a port 60" is made in the hub that, leads to the inner greasing area 46. Aside from the location of grease fitting 58", the remaining structure of this embodiment is identical to FIGS. 1 and 3 and the regreasing function is identical to that described in connection therewith.
Thus, a primary benefit of the present invention is to provide a hub structure that allows wheel bearings to be greased in a fast and efficient manner and without taking the wheel and/or bearing assemblies off the axle. Another feature of the present structure is that it utilizes centrifugal force from wheel rotation to maintain reservoir lubrication of the bearings. The design keeps the grease from being able to escape the bearings in that the grease, in rotation of the hub, seeks a centrifugal level in 52a, 34a, and 46 and 34 and the same in the other embodiment. Furthermore, venting is provided so that thermal expansion of the grease and parts of the wheel do not cause pressured damage of the inner grease seal or related brake parts.
The invention thus achieves the important advantage of using grease for lubricating wheel hubs, and particularly heavy duty hubs such as those on trucks or trailers. As stated before applicant has taken advantage of new developments in grease to provide, with his specially designed hub, efficient and fast packing of the wheel bearings.
It is to be understood that the forms of my invention herein shown and described are to be taken as preferred examples of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention, or the scope of the subjoined claims. | A hub for greasing inner and outer shaft bearings on a spindle having greasing passageways leading in from the front of the hub. One passageway leads to the front of the outer bearing and the other passageway leads to the rear of the inner bearing. A purging passageway is provided between the inner and outer bearings whereby upon pressured grease being forced into greasing passageways in the direction of the purging passageways, new grease is forced in an axial direction through the bearings and old grease and contaminants are purged. An annular seal between the bearings provides the purging passageway with the spindle, such passageway being next to the shaft for maintaining a supply of grease on the shaft. The seal has at least one annular recess for providing additional storage of grease. Grease holding areas are provided adjacent the bearings such that grease is forced into the bearings by centrifugal force when the hub rotates on the spindle. Ventilating openings are provided to prevent buildup of pressure in the hub. A non-ventilating cavity forming plug is provided for substitution of the ventilating plug during a greasing operation. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is directed to manually held and manually manipulated writing implements with means to conform to the hand of the user and to methods for making thereof.
2. Description of the Related Art
Various well known writing instruments have found common use and appeal. Examples include conventional hexagonal cross-sectional pencil shaped to reduce unintended rolling and slippage, and round cross-sectional pens having polymeric slip-reducing materials for the shells thereof and having cap clips for reducing rolling and for attaching to pockets. Generally, these designs have not been as ergonomically well designed for prolonged periods of use based on the way that such pencils and pens are conventionally held during extended writing periods. Additionally, many of these prior pens have a tendency to roll on desk tops.
Prior attempts to improve the ergonomic designs of such pens and pencils have for example lead to the use of various scooped portions for receiving the index finger or have lead to non-uniform curvatures. For pencils, the bodies of which are consumed during use, the use of a non-uniform shape would undesirably result in frequently changing grip configurations following sharpening. Also, various ergonomic pencil configurations would not be suitable for being sharpened in conventional pencil sharpeners. Prior writing instruments have been disclosed in Hochstetler U.S. Pat. No. 5,228,794 issued Jul. 20, 1993 which discloses a writing instrument having groove spirals around a shell; Pleasants U.S. Design Pat. No. 136,595 issued Nov. 2, 1943 which discloses a pen holder Lamb U.S. Design Pat. No. 202,395 issued Sep. 21, 1965 which discloses a holder for a writing instrument having a non-uniform cross-section; Zeckendorf U.S. Design Pat. No. 18,032 issued Jan. 24, 1888 which discloses a lead pencil having a pair of flat sides and a curved side; Eckert et al U.S. Design Pat. No. 22,524 issued Jun. 13, 1893 which discloses a pen holder having spirals; Fuchs U.S. Design Pat. No. 191,341 issued Sep. 12, 1961 which discloses a mechanical pencil; Anderson U.S. Design Pat. No. 237,705 issued Nov. 18, 1975 which discloses a pen; Johansson U.S. Design Pat. No. 323,350 issued Jan. 21, 1992 which discloses a pen; Tucker U.S. Design Pat. No. 31,072 issued Jun. 27, 1899 which discloses a pencil having spirally formed ribs; Kageyama et al. U.S. Pat. No. 5,090,831 issued Feb. 25, 1992 which discloses a writing instrument; Kageyama U.S. Pat. No. 5,207,522 issued May 4, 1993 which discloses a mechanical pencil; and Kageyama et al. U.S. Pat. No. 5,236,270 issued Aug. 17, 1993 which discloses a writing tool; all of which are incorporated herein by reference in their entireties.
The non-uniform design of some of these designs could result in inefficient packaging; some of the uniform designs do not provide for ease in picking up the writing utensil from a resting position; and some of the spiral designs are too tightly wound to provide for comfortable long term writing.
U.S. Pat. No. 5,893,671 (“Patent '671”) issued on Apr. 13, 1999 to the instant inventor discloses a writing instrument with a triangular cross section and a uniform spiral twist of the cross section axially along the length of the instrument. However the pitch of the spiral twist is limited to between 150 and 210 degrees total along the overall length of the instrument. As disclosed in Patent '671, the ergonomic alignment of the surfaces of the writing instrument with the parts of the right hand were achieved with an overall twist of between 150 and 210 degrees over the total instrument length, but only when the direction of twist was counter-clockwise, traversing longitudinally away from the viewer. Similarly, the same ergonomic result was achieved if held in the left hand when the direction of twist was clockwise. Patent '671 failed to address the degree of twist necessary to obtain an ergonomic result for a writing instrument with a clockwise twist held in the right hand, or similarly for an instrument with a counter-clockwise twist held in the left hand.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a writing instrument for a right hand configuration according to the present invention, showing the embodiment with an eraser at the distal end;
FIG. 2 is a plan view of a desk having thereon the writing instrument of FIG. 1;
FIG. 3 is a front end elevational view of the writing instrument of FIG. 1;
FIG. 4 is a perspective view of the right hand of a user holding the instrument of the present invention;
FIG. 5 is a perspective view of an alternative embodiment of the writing instrument for holding in the left hand, and shown with the alternative embodiment of the instrument without an eraser;
FIG. 6 is a schematic of an extrusion process for making the writing instruments of the present invention; and
FIG. 7 is a schematic of a shaving process for making the writing instruments of the present invention.
SUMMARY OF THE INVENTION
The present invention involves a writing instrument having a ergonomic configuration. The instrument is elongated having an equilateral triangular cross-section and having a uniform partial twist along the length thereof. The partial twist permits flat surface engagement for the thumb, index finger, and middle finger and for the dorsal first web space of the hand. The uniform twist in combination with the equilateral cross-sectional shape also permits tight packing in bulk, and the partial twist permits flat sided engagement with the resting surface (desk top).
DETAILED DESCRIPTION OF THE INVENTION
As best shown in FIG. 1, a writing instrument ( 11 ) such as a lead pencil, has an equilateral triangular vertical cross-section, preferably with slightly arcuate (rounded) vertices (edges) where the sides thereof ( 12 , 14 , 16 ) come together which provides the instrument ( 11 ) with the three sides ( 12 , 14 , 16 ). The sides ( 12 , 14 , 16 ) gently spiral about a central longitudinal axis ( 18 ) of the instrument ( 11 ). A writing element ( 20 ), such as a pencil lead, is positioned coaxially along the central longitudinal axis of the writing instrument ( 11 ). The pitch of the spiral is preferably a one-quarter turn from the proximal end ( 22 ) of the instrument ( 11 ) to the distal end ( 24 ) of the instrument ( 11 ), based on an overall preferred length of seven inches typical in the art for pencils and similar writing instruments. The gentle twist of the triangular cross-section of the instrument ( 11 ) permits the instrument ( 11 ) to have one of the three flat sides ( 12 , 14 , 16 ) in parallel contact with the tangent of the contact surface of index finger ( 26 ), middle finger ( 28 ), thumb ( 30 ) and the dorsal first web space of the hand ( 32 ) simultaneously. For an instrument held in the right hand, this alignment would be achieved with a clockwise twist ( 36 ) having a pitch of 10 to 15 degrees per inch of length. More preferably, the pitch would be between 12 and 13½ degrees per inch, and most preferably the pitch would be 12¾ degrees per inch. The amount of pitch preferable to an individual user may vary according to the size of the user's hand and the personal preferences of the user. When a writing instrument so configured is held in the right hand, as shown in FIG. 4, a first side ( 12 ) would be disposed parallel with the surface of the distal end of the index finger ( 26 ), the second side ( 14 ) would be disposed parallel with the surface of the distal end of the thumb ( 30 ), the third side ( 16 ) would be disposed parallel with the surface of the distal end of the middle finger ( 28 ), and the third side ( 16 ) would also be disposed parallel with the surface of the dorsal first web space of the hand ( 32 ), between the index finger ( 26 ) and the thumb ( 30 ).
As shown in FIG. 1, the proximal end ( 22 ) of the instrument (pencil) ( 11 ) has a flat equilateral triangular configuration prior to sharpening. Also shown in FIG. 1, the distal end ( 24 ) of the instrument preferably has an eraser ( 42 ) and which, due to its short length, may either be formed in a conforming spiral twist or may be cylindrical without adversely affecting the desired properties of the instrument ( 11 ). Alternatively, the writing instrument ( 11 ) may lack the eraser, as shown in FIG. 5 .
For using the instrument in the left hand of the user, the direction of the spiral would necessarily be counter-clockwise ( 38 ), as shown in FIG. 5, thereby disposing the same surface ( 16 ) against both the distal end of the middle finger and the dorsal first web space of the left hand
In use, the instrument ( 11 ) when in the form of a pencil, has a sharpened writing point ( 50 ) which is the result of sharpening the proximal end ( 22 ) to a point ( 50 ) so that the lead ( 20 ) is suitable for writing. A preferable pencil would have a preferred length from proximal end ( 22 ) to distal end ( 24 ) of up to 10 inches, more preferably 6½ to 8 inches, and most preferably 7 inches, and preferably each side ( 12 , 14 , 16 ) has a width of approximately a quarter inch to three eighths of an inch. The writing element ( 20 ) may be a graphite lead, in the case of a pencil, or an ink cartridge with a writing nib at the proximal end ( 22 ) in the case of a pen. Common pen nibs include ball points, felt tips, or roller balls.
As shown in FIG. 6, the writing instrument may be made by extruding a body compound about a writing lead, for example a suitable body compound may be a thermoplastic or thermoset composition, and a suitable compound may be a wood powder/glue mixture having suitable levels of wood powder to have desired properties for sharpening of the instrument ( 11 ) and having sufficient levels of glue for the flowability of the wood powder. Conventional wood powders and conventional fast-hardening wood glues may be used in the (coextrusion, extrusion) process. The process involves feeding ( 100 ) a lead ( 20 ) to a extruder ( 102 ), feeding ( 104 ) a body compound ( 106 ) to the extruder ( 102 ), extruding (coextruding) the body compound in fluid form and the lead ( 20 ) to surround the lead with body compound, shaping ( 108 ) the body compound about the lead by forcing the fluid body compound and the lead through a slowly rotating triangular die to produce a spiral triangular cross-sectional body about the lead, hardening ( 110 ) the body compound about the lead by cooling or by reaction (cross-linking); and ( 112 ) cutting the body/lead to produce an unsharpened writing instrument. The instrument may then be sharpened ( 114 ) by a conventional sharpener. Suitable wood powder may be a pine wood powder.
As shown in FIG. 7, the writing instrument may also be produced by feeding ( 116 ) a lead ( 20 ) between two rectangular body halves of wood ( 118 , 120 ), applying glue ( 123 ) to at least one grooved surface of one of said halves, pressing said wooden halves ( 118 , 120 ) to form a square block ( 122 ), allowing said glue to fixedly attach said halves together, passing ( 124 ) said wooden block ( 122 ) through a triangular shaver in a relative rotational arrangement to produce a spiraled body contain the lead, and cutting ( 126 ) the block ( 122 ) to produce the unsharpened writing instrument. The writing instrument may then be sharpened with a conventional sharpener.
In Patent '671, issued to the present inventor, disclosed an ergonomic instrument with an overall twist of 150 to 210 degrees over the full length of the spiral of the instrument. This range of overall twist was the product of the preferred length of 7 inches and the preferred range of pitch of 21 to 30 degrees per inch, essentially twice the pitch of the invention disclosed above. As described in Patent '671, an instrument manufactured into a spiral with a pitch of 21 to 30 degrees achieved an ergonomic fit when disposed in the right hand of the user when the spiral was counter-clockwise. Likewise, an ergonomic disposition would be achieved in the left hand of a user with a clockwise spiral having the preferred pitch of 21 to 30 degrees.
The overall twist is, necessarily, the multiplicative product of the pitch of the spiral and the overall length of the spiral. The ergonomic disposition is a result of the direction and pitch of the spiral, independent of the length of the spiral, and thus of the overall twist. In Patent '671, the invention claimed therein was specified in terms of overall twist based on the preferred 7 inch length. While the overall twist is proportional to the pitch of the spiral when the overall length of the spiral is fixed, its use as a limitation unnecessarily limits the range of lengths for a writing instrument having the desired spiral pitch of 21 to 30 degrees per inch. For example, an instrument having a counter-clockwise spiral pitch of 22 degrees per inch and a length of 6½ inches could be ergonomically disposed in a user's right hand, but would only have an overall twist of 143 degrees, outside the scope of the claims in Patent '671.
In solving the limitations of the '671 patent, another embodiment of the present invention is a writing instrument comprising an elongated body having a uniform equilateral triangular cross-section along the length thereof said body having a uniform spiral around its central axis of a pitch between 21 and 30 degrees per inch of length thereof, wherein the overall twist of the spiral section is less than 150 degrees or greater than 210 degrees and a writing element within said body. This embodiment is manufactured by the same means as previously described herein, by either enclosing a lead ( 20 ) within two halves of wood ( 118 , 120 ) to form a block ( 122 ) using glue ( 123 ) and subsequently passing ( 124 ) the wooden block ( 122 ) through a triangular shaver and cutting ( 126 ) the block ( 122 ) to the desired writing instrument, or by coextrusion of a writing element with a mixture of wood powder and glue.
To use this embodiment to achieve the desired ergonomic alignment between the three flat sides ( 12 , 14 , 16 ) of the instrument and the thumb ( 30 ), index finger 26 ), middle finger ( 28 ) and dorsal first web ( 32 ) simultaneously, the orientation would be opposite that of the prior embodiments, i.e., an instrument with a counter-clockwise spiral would be held in the right hand, while one with a clockwise spiral would be held in the left hand. | A writing instrument having an ergonomic configuration and methods for making the instrument. The instrument is elongated having an equilateral triangular cross-section and having a uniform partial twist along the length thereof. The partial twist permits flat surface engagement for the thumb, index finger and middle finger and for the dorsal first web space of the user's hand. The uniform twist in combination with the equilateral cross-sectional shape also permits tight packing in bulk. A method for making the instrument in the form of a rigid pencil is also provided. | 8 |
FIELD OF THE INVENTION
The invention relates to testing of complex electronic circuit board assemblies. In particular, the invention relates to techniques for functional testing of embedded systems that contain System on Chip (SoC), Programmable System on Chip (PSoC), System in Package (SiP) or other integrated circuits (IC).
BACKGROUND OF THE INVENTION
SoC devices typically include the following components on a single substrate:
(1) microcontroller, microprocessor or digital signal processor (DSP) core(s); and some SoCs that are referred to as multiprocessor systems on chip (MPSoC), may include more than one processor core;
(2) memory blocks including ROM, RAM, EEPROM and Flash memory;
(3) timing sources including oscillators and phased-locked loops;
(4) peripherals including counter, timers and real-time timers,
(5) external interfaces including USB, FireWire, Ethernet, USART, SPI, I2C,
(6) analog interfaces including ADCs and DACs;
(7) voltage regulators and power management circuits; and
(8) various user configurable general-purpose input and output (GPIO) pins.
The manufacture of electronic circuit board assemblies consists of two basic stages: board assembly and board testing. Testing may involve an in-circuit test and/or a functional test. In-circuit testing verifies that the board has been assembled according to vendor manufacturing specifications. Functional testing ensures that acceptable electronic circuits perform functions as designed. Testing of sophisticated electronic circuits requires a complex test system that may entail extensive functional testing protocols and expensive and intricate test fixtures. The process is labor intensive unless it is fully automated.
Implementing suitable test fixtures can be technically challenging and expensive; moreover, the test fixture is often designed only after the circuit board has been completed and prototypes built and tested. This approach causes unnecessary delays in production and product release.
For a simple electronic test system, one or more test signals are applied to a device under test (DUT) and the response of the unit is measured at one or more locations and compared with the responses that would be attained by a standard, operating circuit. Exemplary testing techniques include: (1) “Flying Probe” testing; (2) ROM (Read Only Memory) emulation, (3) using a debug port for testing; (4) using a complex test fixture connecting to each test point on a DUT; and (5) using a complex test system emulating behavior of each external device, which is normally connected to a DUT in an operation mode. These methods are generally difficult to implement in manufacturing processes.
An example of a test fixture for testing a complex circuit board is described in U.S. Patent No. 2006/0250149 to Lan and features a testing platform, a base disposed on the testing platform, a probe coupled to the testing platform and disposed on the base, and a conversion board disposed between the bases. The test fixture's main disadvantage is its mechanical complexity that requires a chain of multiple connections between a test point on the DUT and a probe. Lan does not address functional testing of circuit boards.
Another example of a test system for testing electronic boards that contain at least one processor is described in U.S. Pat. No. 6,842,865 to Nee et al. The test system includes a processor control unit that is connected to a DUT and which runs test routines on the DUT. The system also contains an electronic circuit emulating at least one peripheral device, which is connected to the DUT, a response circuit measuring a response of the DUT to a test routine and a main controller, which communicates with the response circuit in order to obtain the results of the test routine. The complex test system requires much external hardware and complex software to implement.
Finally, an illustrative apparatus for testing computer systems using a complex test fixture is described in U.S. Pat. No. 7,188,276 to Yun. The test fixture incorporates a controller, which controls the testing of the computer system, a field programmable gate array (FPGA) and several programmable memory modules. Each programmable memory module stores configuration data of peripheral devices of the computer system in corresponding versions respectively. Its complexity is the system's major drawback in that it requires external hardware to emulate external components and requires maintaining various versions of programmable memory modules to accommodate different versions of systems being tested.
SUMMARY OF THE INVENTION
This present invention takes advantage of several features that almost any electronic board assembly including SoC already utilizes during normal operations. The invention eliminates shortcomings of prior art test systems and provides a simple and cost-effective method of testing embedded electronic circuits in the manufacturing environment and, in addition, provides on-line diagnostic capability in the industrial environment.
In one aspect, the invention is directed to a system for testing complex electronic circuit board assemblies containing sufficient digital logic processing and input and output means to perform diagnostic self-tests on the functional characteristics of the complex electronic circuit board assemblies that includes:
(a) a complex electronic circuit board containing at least one integrated circuit that can provide data processing, data storage, external data communications, and digital and analog input/output functions such as a System on Chip (SoC) device, a Programmable System on Chip (PSoC), a System in Package (SiP), or other similar devices;
(b) software or firmware code segment providing the instructions for the diagnostic self-tests residing in the at least one integrated circuit as part of the primary code controlling the primary functions of the complex electronic circuit board assembly;
(c) a display to indicate the pass/fail results of the diagnostic self-tests, such as, for example, color LEDs or a LCD;
(d) at least one digital multiplexer controlled by the at least one integrated circuit to switch the source of the input signals between internal simulated digital test signals generated by the at least one integrated circuit and externally generated measurement and control digital input/output signals;
(e) at least one analog multiplexer controlled by the at least one integrated circuit to switch the source of the input signals between internal simulated analog test signals generated by the at least one integrated circuit and externally generated measurement and control analog input/output signals; and
(f) software or firmware code segment that controls the switching between internally generated simulated test signals during diagnostic self-test and externally generated measurement and control signals, and that compares the measured simulated test signals with stored acceptable values of the measured simulated test signals to determine whether the channel of the complex electronic circuit board being tested is within functional specifications.
In another aspect, the invention is directed to a method for functional diagnostic testing of complex electronic circuit board assemblies, which have one or more channels to be tested, wherein the diagnostic tests are conducted by digital logic and software residing onboard a complex electronic circuit board assembly that imposes a known digital or analog voltage or current, as appropriate for the channel under test, that is generated by a digital or analog output of the complex electronic circuit board assembly and electrically connected to the channel under test by either a wiring harness or by a digital or analog multiplexer, and the data read by the channel under test is compared with the stored value of the imposed voltage and required tolerance to determine whether the channel under test is within specifications. The method includes the steps of:
(a) electrically connecting a channel under test for example by connecting the wiring harness, if one is required, to appropriate connectors on the complex electronic circuit board assembly;
(b) applying an instruction to the complex electronic circuit board assembly to initiate execution of a software or firmware code segment that controls the diagnostic test, for example, by closure of a hardware switch built onto the complex electronic circuit board that is connected to at least one integrated circuit or by sending a software command to the complex electronic circuit board via an external communication means;
(c) the software or firmware code segment sequentially connects predetermined output analog channels to predetermined analog input channels, applies a predetermined voltage or current and measures the value from the connected analog input channel;
(d) the software or firmware code segment compares a value read from the connected analog input channel to the applied predetermined voltage or current and calculates whether the value measured is within a specified tolerance for that channel;
(e) the software or firmware code segment outputs a signal to an indicator LED, LCD, or to the external communications means to indicate the functional status, or optionally the voltages or currents measured, of the channels under test;
(f) the software or firmware code segment sequentially connects predetermined output digital channels to predetermined digital input channels, applies a predetermined value and measures a value from the connected digital input channel;
(g) the software or firmware code segment compares a value read from the connected digital input channel to the applied value and calculates whether the channels are functional; and
(h) the software or firmware code segment outputs a signal to an indicator LED, LCD, or to the external communications means to indicate the functional status, or optionally the voltages or currents measured, of the channels under test.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a SoC-based board assembly;
FIG. 2 illustrates a DUT that includes an LCD display;
FIG. 3 illustrates a DUT that does not include an LCD display;
FIG. 4 is a flowchart of a test routine; and
FIGS. 5 and 6 illustrate implementation of testing digital inputs and outputs, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A typical SoC circuit interfaces with a number of field devices either through analog or digital inputs and outputs. Typically, an analog input signal is a voltage from a sensor or transducer, which represents a measurement of various physical parameters: temperature, pressure, moisture etc. An analog output signal (voltage) represents a control signal, which is sent to a transducer or actuator to adjust various physical parameters. A digital output signal (single bit) typically represents a control signal that is used to change the status of a field device, e.g. turn a bulb on. A digital input signal is used to monitor a status of the field device, e.g., heater is off.
A typical design using SoC includes an electronic circuitry that isolates (separates) low voltage portion of the circuit (SoC and associated digital and analog circuits directly connected to SoC) from that part of the circuit that directly interfaces with field devices. This separation is used to isolate external devices, which typically require much higher voltages to operate (e.g. powered from +12VDC, +15VDC, +24VDC etc.). FIG. 1 shows a simplified block diagram of a SoC-based electronic board assembly 2 which includes a SoC 4 , isolation for digital inputs/outputs 6 , digital inputs 10 , digital outputs 12 , connectors for connecting field devices 20 , isolation for analog inputs/outputs 8 , analog inputs 14 , analog outputs 16 and connectors for connecting field devices 18 . Wire harness 2 connects digital inputs with digital outputs and wire harness 1 connects analog inputs with analog outputs.
When a LCD display 32 is also included in the design of an electronic board, a test system can consist of only of a DUT 30 as shown in FIG. 2 . (The DUT 30 can be similar to DUT depicted in FIG. 1 .) In this configuration, behavior and status of all field devices are simulated by the test program. In some cases where field devices need to be simulated externally, a simple test fixture may need to be built for this purpose. In one embodiment, the test fixture could include just a set of loop-back cables connecting digital inputs with digital outputs and analog inputs with analog outputs. If inputs and outputs require different voltages some additional circuitry may need to be used to adjust voltage levels to desired values. These additional circuits could be either implemented as part of a DUT or on the test fixture.
When LCD display is not a part of DUT, an external LCD 42 may be connected to a DUT 40 through a dedicated connector as shown in FIG. 3 . Since a typical SoC has already built-in interfaces for USB, Ethernet, USART etc. 48 , test results can also be sent to an external PC 46 or a web server and displayed on an external monitor 40 .
A preferred method of implementing the invention is to include a test program within the main program of SoC (e.g., as a subroutine). Typically this test program is a small portion of a code that is included in the main program. During normal operating mode only the main program is executed. The test program is executed only if a request to perform a test is received by the SoC. During normal operations, the SoC periodically checks if the request for the test has been received.
An example of a test sequence as shown in FIG. 4 begins with start step 70 and terminates at step 86 or 88 when the channel is determined to be operating normally 74 or if the channel fails the test 82 . Specifically, a request for the execution of the test program can be initiated either through a hardware trigger, e.g. changing position of a jumper or toggling a switch mounted on DUT, or a software trigger (e.g., an interrupt) designated as step 72 (“Is this a Test Mode?”). After the request for executing the test program is detected, an appropriate portion of the code is executed to perform the required test routines 76 . Results of the test can be displayed 78 on LCD display or sent to an external PC or server for displaying on an external monitor. If the channel fails the test at step 80 , the results can be displayed 82 before the test routine is terminated. If the channel passes, the results can be displayed 84 before initiating inquiry step 72 .
There are several options for displaying the test results. For example, a DUT can provide a simple and instantaneous display of the status of the test results using LEDs that are installed on the electronic board, where GREEN LED means “all test passed” and RED LED means “at least one of the test has failed”. This method enables a very quick, fully automated, and efficient way of identifying boards that failed the test. Alternatively, an LCD display or PC monitor can be employed to provide identification of the failed tests (such as the specific channel that failed), the expected result (when operating normally) and the actual result (failure signature) in various forms (e.g., simple text message or graphical representation).
A test routine may include the following sub-routines: (1) Test Mode Routine, (2) Display Test Results Routine, (3) Display Test Passed Routine, and (4) Display Test Failed Routine
Test Mode Routine
In this routine, an algorithm continuously scans all analog and digital I/O values currently present at all GPIOs. All analog values representing measurement and control signals for analog devices (sensors, transducers, etc.) are stored in a single array, which holds all values in a predetermined order. An alternative is to store these values in several arrays, which may hold control signals and measured values separately for ease of indexing and further processing. Storing digital values does not require arrays. Since these values are typically single bits, they can be stored as a byte or a word (8-bit, 16-bit, 32-bit, etc.) or any combinations of these depending on the system scale (number of GPIOs required) and SoC architecture.
The expected values for both analog and digital signals are stored in separate memory locations. This could be separate arrays, hard-coded vales in a code or look-up tables.
During the Test Mode routine, scanned values are constantly compared with expected values and results of that operation are stored in a single array or several arrays depending on system complexity and number of GPIOs used. If results of all comparisons are positive, Test Flag variable is set to HIGH (where HIGH means “Test has passed”), if at least one comparison yields negative result, Test Flag is set to LOW (where LOW means “Test has failed”).
Testing of digital inputs and outputs will require looping back digital inputs with digital outputs. That could be achieved either by using a combination of multiplexers and/or digital switches controlled by the test software or external hardware (e.g., wire harnesses).
FIG. 5 shows an implementation of testing a single digital input using two multiplexers 52 , 54 and a control algorithm in the form of test software 50 , 56 . Multiplexer 52 has 2 inputs with one of its inputs being preferably hardwired to an input connector (used by field device to bring input signal). The second input is controlled by the test routine. The “TEST ENABLE” control signal from test software 56 determines a mode of operation of multiplexer 52 ; in normal mode, the field device input is selected and in the test mode the field device input is simulated by software. The output from the multiplexer 52 is connected to a second multiplexer (multiplexer 54 ) as a second input. The first input of the multiplexer 54 is generated on a board and is derived from the intended board functionality. The output of multiplexer 54 is connected directly to the output connector. The signal that appears on this output is controlled by the same “TEST ENABLE” signal. The output signal of the multiplexer 54 is monitored by the test program and is used for comparing input and output values that are stored in the data arrays.
FIG. 6 shows an implementation of testing a single digital output using two multiplexers 60 , 62 and a control algorithm in the form of test software 60 , 66 . This testing process is similar to that for testing a single digital input as shown in FIG. 5 . Multiplex 62 receives a signal either from a field device or one that is simulated by test software 66 . The output signal of multiplexer 62 is used to simulate output in the test mode. During normal operation multiplexer 64 will pass a signal that is derived from the intended board functionality to control digital output.
Testing of digital inputs is done by setting them either HIGH or LOW and verifying that corresponding outputs respond accordingly. Testing of digital outputs is very similar. In general, a routine for testing of digital inputs and outputs can use the same software architecture or hardware (e.g., wire harness).
Testing of analog inputs, in its simplest form, may only require a single value. In this case, a constant voltage is applied to each analog input and it is compared with an expected value stored in the data array. Similarly, testing of analog output will require measuring voltage at the output and comparing that value with one stored in the data array.
Testing of analog inputs and outputs can utilize a similar approach to that for testing digital inputs and outputs as illustrated in FIGS. 5 and 6 . System generated input/output analog test signals can be compared with corresponding measured analog signals. If using a single analog value does not satisfy test requirements, a range of simulated analog values can be used. Furthermore, each analog input can use different voltages, different ranges of values or a combination of all above, depending on desired functionality. The test software may include a number of loops and various algorithms for testing different voltage ranges.
Display Test Results Routine
In this routine, algorithm continuously displays results of measured analog and digital values on LCD display. Typical information displayed may include a date and time of the test, a name of each monitored GPIO, a name of a parameter measured, parameter current value, parameter expected value and its engineering unit of measure (e.g. voltage, temperature, pressure, etc.).
Display Test Passed Routine
In this routine, algorithm displays “PASS” message on LCD display. Typical information displayed may also include a date and time of the test. In addition, the same message can be sent to an external PC and displayed on an external monitor. In addition a dedicated GREEN LED on the board is illuminated to provide a visible status that all tests have passed.
Individual test results for each parameter can be reviewed in this mode. By pushing dedicated buttons on the DUT, the test results can be viewed repeatedly in a predetermined order or selected randomly. In this mode corresponding values are being fetched from an array (arrays), which holds the measurement results. These results then gets converted to a desired format and displayed with its name and a unit of measure. Results for digital I/Os are displayed with its signal name and current status (typically either “ON” or “OFF”). The GREEN LED, displaying test status result, is set by the Test Flag variable.
Display Test Failed Routine
In this routine, algorithm displays a “FAILED” message on a LCD display. Typical information displayed may also include a date and time of test. In addition, the same message can be sent to an external PC and displayed on an external monitor. In addition a dedicated RED LED on the board is illuminated to provide a visible status that at least one test failed.
Individual test results for each parameter that has failed can be reviewed in this mode. By pushing dedicated buttons on the DUT the test results can be viewed repeatedly in a predetermined order or selected randomly. In this mode, values of parameters, which were flagged as failed, are being fetched from an array (arrays), which stores the measurement results and then converts these results to a desired format and displays them with its name and a unit of measure. Results for digital I/Os are displayed with its signal name and current status (typically either “ON” or “OFF”). The RED LED, displaying test status result, is set by the Test Flag variable.
The foregoing has described the principles, preferred embodiments and modes of operation of the present invention. However, the invention should not be construed as being limited to the particular embodiments discussed. Thus, the above-described embodiments should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by workers skilled in the art without departing from the scope of the present invention as defined by the following claims. | Functional diagnostic testing of an electronic circuit board assembly with one or more embedded channels to be tested includes steps of: (a) connecting a channel under test; (b) imposing a known digital or analog voltage, as appropriate for a channel under test, that is generated by a digital or analog output of the electronic circuit board assembly; and (c) comparing data read by the channel under test with the stored value of the imposed voltage and required tolerance to determine whether the channel under test is within specifications. Diagnostic test implemented by digital logic and software residing onboard the electronic circuit board assembly. Execution of software or firmware code segment controls the diagnostic test sequence. Signal switching is facilitated by digital and analog multiplexers. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to apparatus of the type commonly known as "deflakers" which are used in the preparation of paper making stock, especially from waste paper materials of widely varying characteristics.
Deflakers are often used to perform a defibering operation on relatively coarse stock which has either been extracted from a pulper without screening, or which has been rejected by a relatively coarse screen after extraction from a pulper. Such stock can therefore be expected to contain not only a high proportion of usable but still undefibered paper material, but also substantial quantities of reject materials such as plastic, tramp metal such particularly as staples, screws, wire, nuts and bolts, and other hard contaminant materials.
A significant problem which has been encountered by deflakers of the prior art has been their inability to handle successfully stock which contains tramp metal. More specifically, the prior art deflakers have shown a tendency to be self-destructive in that they will accept stock containing tramp metal, but their filling or tackle becomes so damaged in attempting to disintegrate the metal that it becomes useless for further defibering action.
Other practical disadvantages of prior art deflakers have included the cost of their filling or tackle, its tendency to wear to the point of unacceptably low effectiveness, and the time and effort required for its replacement, which commonly includes the necessity of disconnecting and reconnecting one or both of the inlet and outlet pipe lines. Further, prior art deflakers often permit stock to flow through grooves in the working face of the rotor or stator without entering the high shear defibering zone between those faces, which results in poorly defibered stock.
SUMMARY OF THE INVENTION
The primary object of this invention is to provide a deflaker which will have high defibering efficiency, in which there will be minimal possibility for stock to bypass the working zone, and especially which will prevent tramp metal from entering the working zone and thereby protect itself against self-destruction.
An additional object of the invention is to provide such a deflaker wherein the working elements are relatively low in cost, from the standpoint of both manufacturing costs and service life, which can be removed and replaced quickly and easily without the necessity of disconnecting any pipes, and wherein the rotor can be operated selectively in either direction with equal effectiveness and will therefore provide two sets of working edges which can be used in turn after the first set has become worn, or on a more frequent basis to prolong the wear life of the working edges.
These objectives are achieved in accordance with the invention by deflaking apparatus wherein the housing encloses an inlet chamber of relatively large dimensions in comparison with the working elements which operate therein and comprise a rotor and a stator having complementary frusto-conical working faces. Each of these faces is provided with one or more circumferential rows of pockets spaced from each other to provide an extending land area between adjacent pockets, and the edges of each of these land areas on the rotor extend generally lengthwise of the rotor.
The apparatus is preferably provided with a reversible drive so that each set of land edges can operate selectively as leading edges. When the rotor is running in one direction, these leading edges tend to be progressively rounded, but at the same time, the trailing edges tend to become sharpened. In fact, if relatively soft metals are used in the rotor, a burr will form on the trailing edges which is relatively fragile but sharp. Preferred results are obtained by relatively frequent changing of the direction of rotation of the rotor, thereby utilizing the beneficial effects of trailing edge sharpening or reconditioning and correspondingly significantly prolonging wear life and constant operating efficiency.
Many variations of the patterns of the working faces are possible, and in a preferred embodiment, each of the pockets in the rotor and stator has generally axially extending side walls and one generally radially extending end wall, which is the back wall in the rotor and the front wall in the stator. The peripheries of these end walls and the intervening areas of the working face combine to form circumferential lands on both the rotor and stator. The axial dimensions of the rotor and stator themselves and of the pockets in their working faces are of predetermined relationship such that each of these circumferential lands is in opposed relation with a row of pockets in the other working element, thereby forcing the stock to travel back and forth between pockets in the rotor and stator as it passes through the working zone from the inlet port to the outlet port of the housing.
The use of frusto-conical working faces contributes an additional operational feature of the apparatus in that relative axial adjustment of the rotor and stator provides for corresponding adjustment of the working clearance between their working faces. This enables the operator to compensate from time to time for wear of the working elements so that the apparatus can produce uniformly treated pulp over long periods of time in spite of wear. Also, this enables the operator to compensate when more or less easily defiberable material is fed to the apparatus.
Special provision is made in accordance with the invention for minimizing the possibility for access by tramp metal and other high specific gravity materials to the working zone. This result is accomplished in part by the relatively large diametral dimensions of the inlet chamber as compared with the smaller ends of the rotor and stator which extend into this chamber. The centrifugal forces generated by rotation of the rotor have a natural tendency to cause high specific gravity materials to migrate to the outer wall of the inlet chamber for easy removal rather than to remain in the flow of stock which enters the working zone.
Positive protection against tramp metal and the like is provided by a front end cap on the rotor which includes a peripheral skirt portion of greater diameter than the inner diameter of the smaller end of the stator and thereby forms with the front end of the stator a circumferential slot of relatively small axial dimension through which all stock must pass in order to enter the working zone. This cap enhances the centrifugal action which causes high specific materials to move outwardly away from this inlet slot, and the dimensions of the slot itself further discourage the entry of overlarge pieces. The inlet chamber is provided with one or more clean-out ports from which such reject materials can be easily removed from time to time.
An additional feature of the invention, which is contributed to by the relative dimensions of the inlet chamber and of the rotor and stator, is the case of replacement of these working elements. The end of the housing which encloses the inlet chamber is provided with a cover plate enclosing an opening larger in diameter than the rotor and stator, so that when this cover plate is removed, the rotor and stator can be dismounted, taken out through the resulting opening, and replaced with minimum down time and without requiring disconnection of any piping leading to or from the apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical axial section through deflaking apparatus in accordance with the invention;
FIG. 2 is an end view looking from left to right in FIG. 1;
FIG. 3 is an end view looking from right to left in FIG. 1;
FIG. 4 is a fragmentary plan view of the drive end of the apparatus shown in FIG. 3;
FIG. 5 is an enlarged fragment of FIG. 1;
FIG. 6 is a fragmentary view of the working face of the rotor of FIGS. 1 and 5;
FIG. 7 is a section on the line 7--7 of FIG. 6;
FIG. 8 is a diagram identifying reference angles for describing the geometry of the pockets in the rotor;
FIG. 9 is a fragmentary view looking axially toward the working face of the stator from right to left in FIG. 5;
FIG. 10 is a fragmentary view of the working face of the stator taken at right angles to FIG. 9;
FIG. 11 is a fragmentary and somewhat diagrammatic axial section similar to FIG. 5 and illustrating the operation and working relation of the rotor and stator.
FIG. 12 is a fragmentary view similar to FIG. 1 and taken on the line 12--12 in FIG. 13 to show a modified construction; and
FIG. 13 is an end view looking from left to right in FIG. 12.
FIG. 14 is a view similar to FIG. 6 and showing a modified arrangement of pockets in the working face of a rotor in accordance with the invention;
FIG. 15 is a view similar to FIG. 14 and showing another modified arrangement of rotor pockets;
FIG. 16 is a fragmentary and somewhat diagrammatic view showing working elements in accordance with the invention wherein both the rotor and stator include a pair of working faces of substantially different radial dimensions;
FIG. 17 is a fragmentary and somewhat diagrammatic view showing another modification of the invention wherein the rotor has working faces at both ends thereof each cooperating with a pair of stators;
FIG. 18 is a view similar to FIG. 17 and showing the reverse arrangements of FIG. 17 wherein the larger ends of the working faces of the rotor are at the opposite ends of the rotor body;
FIG. 19 is a fragmentary sectional view showing a form of rotor and stator in accordance with the invention wherein the pockets in the working faces are milled to an arcuate contour in axial section; and
FIG. 20 is a similar view showing another pocket contour;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The main body 10 of the deflaking apparatus includes at one end an essentially cylindrical housing portion 11 enclosing the inlet chamber 12 to which the stock is delivered through the inlet port 13 at the top of the housing 11. The annular outlet chamber 15 at the back of the housing 11 is similarly provided with an outlet port 16 at the top, and at the bottom of the chamber 12 is a pair of clean-out ports 17. The remainder of the main body 10 beyond the housing portion 11 comprises the supporting and adjusting structure for the rotor drive shaft 20, as described in detail hereinafter.
The inlet and outlet chambers 12 and 15 within housing 11 are separated by the working elements of the apparatus, which are the frusto-conical rotor 22 on shaft 20 and the complementary stator 25. The stator 25 is secured within the housing 11 by three angularly spaced clamps 26 of L-shaped section and screws 27 threaded into a mounting ring 28 welded within the housing 11, one of these clamps 26 being shown in FIG. 5 and the others being equidistant therefrom and from each other. The rotor 22 is mounted on the front end of the shaft 20 by a hub 30 keyed on the end of the shaft and held in place by a retainer plate 31 and screw 32. The hub 30 includes a flange 33 at its inner (larger) end, and the rotor 22 is clamped against this flange by means of the end cap 35 which is mounted on the hub 30 by a series of screws 36.
Referring to FIGS. 6 and 7, the frusto-conical working face of the rotor 22 is provided with two circumferential rows of angularly spaced pockets separated by axially and circumferentially extending land areas. The pockets 40 in the front row are separated by land areas 41 in equally spaced relation around the small end of the rotor. Each of these pockets 40 has side walls 42 which extend generally axially of the rotor, and a back wall 43 extending generally radially of the rotor. This arrangement provides edges 44 along opposite sides of each of the land areas 41 .Iadd., but the bottom wall 56 of each pocket extends from the associated back wall 43 to the surface of the rotor so that the back wall 43 constitutes the only end wall of the pocket.Iaddend..
The outer peripheries of the back walls 43 meet the working face of the rotor and form therewith a circumferential land 45 which separates the row of pockets 40 from the row of pockets 50. These pockets 50 are similar to the pockets 40 in shape but smaller in all their dimensions, and they are similarly separated by axial land areas 51. The side walls 52 of the pockets 50 also extend generally axially, and each pocket has a generally radially extending back wall 53. The working edges 54 of the land areas 51 correspond to the similar working edges of the land areas 41, and the peripheries of the back walls 53 meet the working face of the rotor and form therewith a second circumferential land 55 around the large end of the rotor.
As best shown in FIGS. 8 and 11, the bottom walls 56 and 57 of the pockets 40 and 50 extend generally parallel with the axis of the rotor, or at a relatively small angle with respect thereto, and this results in making each pocket of increasing depth from front to back, with the maximum depth being along its back or end wall. Further, the pockets 40 and land areas 41 are fewer in number and individually wider than the pockets 50 and land areas 51, which provides a correspondingly greater number of working edges 54 around the larger end of the rotor. As an example of satisfactory dimensions, a rotor having a maximum diameter of 19 inches at the outer edge of the land 55 may have 54 land areas 41 each approximately 0.40 inch in width, and 72 land areas 51 each approximately 0.30 inch in width.
The geometric configuration of each pocket 40 and 50 can be described generally in terms of several angles with reference to FIG. 8, wherein a represents 1/2 of the included angle of the frusto-conical working face of the rotor, b is the angle defined by the bottom wall 56 of a pocket 40 and a line 58 parallel with the axis 59 of the rotor, and hence also with the axis 59, and the axis of the rotor, and c is the angle defined by the pocket back wall 43 and the rotor axis. Also, referring to FIG. 6, d is the included angle of the pocket side walls 42. For good design in accordance with the invention the relations of these angles should be:
______________________________________Angle Range Preferred______________________________________a 15° to 75° 20° to 30°b Smaller than c 3° to 6° and greater than 0°c Greater than a but At least 30° greater not more than 120° than a to 90°d 0° to approximately 3° to 15° 60°______________________________________
The conditions to be considered in selecting a cone angle for the rotor working face include the fact that outside of the indicated range, pocket depth is so small that the cross section through which the slurry flows becomes impractically small. The preferred included angle of 40° to 60° gives sufficient pocket cross section and does not result in excessive diameter increase from the feed end of the rotor to its discharge end, which is desirable because excessive diameter increase produces greater pressure buildup and results in excessive axial thrust values. Note also that as shown, it is convenient to connect the bottom and back walls of each pocket by a smoothly curved portion so that the angular conditions listed above are fulfilled near the surface of the rotor.
The stator 25 has a frusto-conical working face which is in all material respects complementary to that of the rotor 22. Referring to FIGS. 9-10 it includes a front row of pockets 60 separated by land areas 61 and each pocket having side walls 62, which extend generally axially of the stator, and a front wall 63 which extends generally radially of the rotor. The land areas 61 have working edges 64, and there is a circumferential land 65 at the small end of the stator .Iadd., but the bottom wall of each stator pocket extends from its associated front wall 63 to the surface of the stator so that the front wall 63 constitutes the only end wall of the pocket.Iaddend..
The pockets 70 in the second row are smaller in all dimensions than the pockets 60 and are similarly separated by land areas 71. The side walls 72 of each pocket 70 extend generally axially toward the large end of the stator from the generally radially extending front wall 73. The land areas 71 have working edges 74 like those on the other land areas, and there is a circumferential land 75 which separates the two rows of pockets and is composed of the exposed peripheries of the pocket walls 73 and the intervening portions of the working face of the stator. The configuration of each of the pockets 60 and 70 should conform to geometric limitations corresponding to those discussed for the rotor pockets 40 and 50.
FIG. 11 illustrates somewhat diagrammatically the working relation of the working faces of the rotor 22 and stator 25. The parts are so proportioned that when these working faces are in proper working relationship, with a close clearance therebetween, the small end of the rotor projects outwardly from the stator, the several circumferential lands are in axially staggered relation with each other, and each of these lands is in radially opposed relation with a row of pockets in the complementary working element. As a result, the stock must enter the working zone through the shallow ends of the rotor pockets 40, and since it cannot advance axially in any pocket 40 beyond its rear wall 43, it must transfer into the stator pockets 60, but it cannot travel in them beyond the circumferential land 75 and must therefore enter a rotor pocket 50. Once again, axial flow in the pockets will be interrupted by the pocket back walls 53, causing a further transfer of the stock to the stator pockets 70 before it reaches the outlet chamber 15.
The passage of stock through the working zone as summarized in the preceding paragraph is illustrated by the series of arrows in FIG. 11. It will be understood, however, that it will not be possible for the stock to follow this path in a continuous axial direction. Instead, the solid material in the stock will be subjected to repeated working between the surfaces of opposed land areas, and especially to the working action of the rotor pocket edges 44 and 54 as they travel past successive stator pockets, the land areas therebetween, and especially the land edges 64 and 74 on the stator. The stock is therefore effectively prevented from bypassing the working zone by following only open channels through successive pockets, and this result is also contributed to by the variation in the size and number of the pockets in the successive rows in both the rotor and stator.
As previously noted, the land edges 44, 54, 64 and 74 are particularly active in the defibering operations of the apparatus, and it necessarily follows that in due course, they may become worn or blunted. With the rotor and stator pockets so formed that these land edges extend generally axially, or at equal but opposite angles to the axis, however, it is then necessary only to reverse the direction of the rotor when this has occurred, or preferably to reverse the drive at frequent intervals and thereby to obtain the self-sharpening action previously described. This is easily done by providing the rotor shaft 20 with any suitable conventional reversible drive, or a reversing switch for a standard motor, as indicated diagrammatically at 77, thus more than doubling the service life of a single set of working elements. In addition to this service life advantage, the rotor and stator of the invention offer the further practical advantage that they can be cast without expensive coring or readily fabricated from blanks of stainless steel or other desired metal which can be appropriately hardened.
The action of the invention in minimizing the possibility that tramp metal and other high specific gravity metals can reach the working zone is contributed to by a number of factors or features. In the first place, with the front end of the rotor substantially smaller than the inner diameter of the inlet chamber 12, e.g. a minimum diameter of 13 inches across the bottoms of the pockets 40 as compared with an inner diameter of 24 inches for the chamber 12, the rotation of the rotor alone will develop centrifugal force which will have a strong tendency to cause the high specific gravity materials to migrate toward the wall of the housing 11 rather than to remain sufficiently near the center of the chamber to be in position to enter a rotor pocket.
More positive assurance against the access of heavy materials to the rotor pockets 40 is provided by the rotor cap 35, which is a frusto-conical member of sufficiently greater base diameter than the small end of the rotor to form an annular skirt 80 radially overlying the inlet ends of the rotor pockets 40. As shown, this skirt 80 is of sufficiently greater diameter than the inner diameter of the small end of the stator, e.g. 1 inch or more, that it forms with the outer end wall of the stator a circumferential slot 81 through which stock must pass in order to enter a rotor pocket 40, preferred results having been obtained with this slot having an axial dimension of approximately three-fourths inch. In addition, the rotation of the rotor cap 35 develops centrifugal force which will be most effective against any heavy materials near its outer periphery, and which will thus augment the action of the rotor in causing such heavy materials to travel to the outer wall of the housing 11, and ultimately to the trough 82 extending between the cleanout ports 17.
The relative dimensions of the rotor 22 and the housing 11 noted above also contribute significantly to another feature of the invention, namely the ease of replacement of the working elements. As shown in FIGS. 1 and 2, the front wall of the housing 11 is formed by a circular cover plate 85 removably secured by screws 86 to a ring 88 welded inside the housing 11. Removal of this cover plate exposes the entire interior of chamber 12 through the resulting opening, which is larger in diameter than both the rotor and stator. The removal of the latter for replacement through this opening therefore requires only the release of the screws 36 mounting the rotor cap 35 on hub 30 and of screws 27 holding the stator clamps 26 in place, since the hub 30 remains on the shaft. It is especially advantageous that this servicing operation does not require any interference with the pipe or hose connected to either of the ports 13 and 16, except other than to close whatever valve may control each such pipe or hose.
The invention also provides for relative adjustment of the rotor 22 and stator 25 to the desired working clearance of their working faces, the preferred range of which has been found to be 0.01 to 0.15 inches, with 0.03 inches providing optimum stable operation. Referring to FIGS. 1 and 3-4, the shaft 20 is supported by a thrust bearing 90 and radial bearing 91 in a tubular housing 92 which is in turn supported for controlled axial adjustment in a pair of inner and outer wall members 94 and 95 welded within the portion of main body 10 beyond the housing 11. An adjusting plate 99 is mounted on the outer end of the bearing housing 92 by a plurality of screws 96 and is provided with means for effecting its controlled adjustment with respect to the wall 95.
More specifically, an adjusting screw 100 is threaded through the adjusting plate 99 and passes freely through a bore in the wall 95. Nuts 101 and 102 are threaded on the screw 100 on either side of the wall 95, and it will be seen that by releasing either of these nuts and tightening the other, the screw 100 can be pushed or pulled through the wall 95 and thereby cause corresponding movement of the adjusting plate 99, the bearing housing 92 and the shaft 20. An indexing screw 105 is fixed with its head on the inner side of the adjusting plate 99 to form a stop limiting inward movement of plate 99 with respect to wall 95 beyond the position in which the working faces of the rotor and stator are just out of frictional contact.
FIGS. 12 and 13 show a modified construction wherein the cover plate 110 for the housing portion 111 incorporates baffle means for guiding the stock to the center of the inlet chamber 112 from the inlet port 113. An annular partition plate 115 having a central opening 116 is mounted on the inside of the cover plate 110 by a plurality of radially extending webs 117 and a central tubular member 120. The webs 117 each have a large center hole 121 therein, and there is a similar hole 122 in the lower side of the tubular member 120.
With this construction, stock entering through the inlet port 113 can reach the interior of the inlet chamber 112 only by passing through at least two of the holes 121, the hole 122 and the opening 116. It is therefore virtually impossible for heavy specific gravity material to reach the inlet chamber, and if any such material, e.g. tramp metal, should be trapped on the upper side of the tubular member 120, it is easily removed by taking off this cover plate assembly from time to time and dumping such accumulated reject. This cover plate construction also offers the further practical advantage of reducing the inlet pressure requirements, which would otherwise be determined by the radial pressure buildup resulting from rotation of the stock in the inlet chamber, but this rotational effect cannot influence the entering flow until the stock has passed through the opening 116.
The working members of the apparatus shown in FIG. 12 are identified generally at 125 and are of the same construction described in connection with FIGS. 1-11. However, FIG. 12 does show a modified arrangement of discharge port comprising an elbow 130 mounted on the back wall 131 of that portion of the housing enclosing the outlet chamber 135. This part of the housing, however, could be constructed in the same manner shown in FIG. 1.
FIGS. 14-20 illustrate a variety of modifications of the apparatus of FIGS. 1-13 which also embody the principles of the invention. Thus FIG. 14 shows a fragment of a rotor 140 having two peripheral rows of pockets in its working face but with each row consisting of alternating relatively long and relatively short pockets. More specifically, the row of pockets adjacent the smaller end of the rotor comprise relatively long pockets 141 alternating with relatively short pockets 142, and the other row similarly comprises relatively long pockets 143 alternating with relatively short pockets 144. The rotor 140 also has circumferential lands 145 adjacent its larger end and between the two rows of pockets of its working face, and each pocket should conform generally to the same geometry disclosed by the above in connection with FIG. 8. The stator with which the rotor 140 is used will preferably have a complementary pattern of rows of alternately long and short pockets in the working face thereof.
FIG. 15 shows a modified rotor 150 generally similar to the rotor 140 in that the row of pockets adjacent the smaller end thereof comprises alternating long pockets 151 and short pockets 152. The rotor 150 also includes a second circumferential row of pockets 153 shown as of essentially the same dimensions as a long pocket 151 and in axially uniformly spaced relation therewith. Since this arrangement would leave a relatively wide land area between alternate pockets 153 and the larger end of the rotor, an additional relatively short pocket 154 is provided in each such space. The rotor 150, however, still includes circumferential lands 155 at the larger end thereof and between the two rows of pockets thereon. The stator with which this rotor 150 is used will preferably have a complementary pattern of pockets in its working face.
FIG. 16 shows a modified construction of working elements in accordance with the invention wherein the rotor 160 has a frusto-conical working face 161 of relatively small average radius adjacent the inlet end thereof and a working face 162 of substantially larger average radius adjacent its discharge end. The working face 161 has pockets 163 therein similar to the pockets 40 as already described. There is also an annular land 165 extending radially from the larger end of the working face 161 to the smaller end of the working face 162. The pockets 166 in the working face 162 are also similar in geometry and distribution to the pockets 163, and there is therefore a circumferential land 167 around the larger end of the working face 162.
The stator 170 in FIG. 16 is shown as essentially complementary to the rotor 160, in that it has a small radius working face comprising similar pockets 173, and land 174, a radial land 175, and a large radius working face comprising pockets 176 and a land 177 all arranged in complementary fashion to the corresponding portions of the rotor 160. It should also be understood that either or both of the working faces of the rotor and stator can have a plurality of rows of pockets therein similarly to the rotor 22 and the stator 25, and also that the dimensions and arrangement of all of these pockets are subject to variation such as described in connection with FIGS. 14-15. Similarly the rotor 160 will preferably be provided with an end cap similar to and for the same purpose as the end cap 35.
In the modification shown in FIG. 17, the rotor 200 is double ended and cooperates with a pair of stators 202 in a housing 205 having an inlet chamber 206 at each end thereof provided with its own inlet port 207, and a centrally located annular discharge chamber 208 provided with a discharge port 209. The rotor 200 includes a frusto-conical working face 211 at one end thereof, a similar frusto-conical working face 212 at the other end, and a cylindrical central surface 213. Each of the working faces 211 and 212 is shown as of a construction generally similar to the rotor 22 as already described.
The two stators 202 in FIG. 17 are shown as of identical construction comparable to stator 25 as already described, and each cooperates with its complementary rotor face 211 or 212 in similar manner. This double ended rotor cooperating with two stators offers not only double the working capacity for a small increase in housing size, but also the advantage that with the rotor splined or otherwise mounted for free axial movement on its drive shaft 215, as shown, it can float between the two stators as required to balance the hydraulic pressure conditions between each pair of complementary working surfaces, and thereby to eliminate axial thrust on the shaft 215 and its supporting bearings (not shown). It will also be apparent that the rotor 200 can be provided at each end thereof with an end cap like and for the same purpose as the end cap 35.
FIG. 18 shows a double ended rotor 220 of the reverse configuration from rotor 200 in that it has a cylindrical portion 222 of minimum diameter at its middle portion and frusto-conical working portions 221 and 223 at opposite ends thereof, each of these working portions having its section of maximum diameter at the outer end of the rotor body, and the three sections being secured together as by bolts 224. The two stators 225 in FIG. 18 correspond to stators 202 in FIG. 17 but are arranged in the opposite manner for proper cooperation with the complementary working surfaces of the rotor 220.
The housing 230 in FIG. 18 includes an inlet chamber 231 located generally centrally and having an inlet port 232, and there are discharge chambers 233 and 234 adjacent opposite ends of the rotor 220 and each having a discharge port 235. The rotor 220 includes a pair of circumferential flanges 237 which correspond in function to the end cap 35 to block tramp metal and the like from access to the resulting entry slots to the spaces between the working surfaces of the rotor and stators, and it is for this reason that the rotor is made in three portions for installation with the stators 225. It will also be apparent that the rotor 220 can float on its supporting shaft 238 in the same manner, and with the same advantages, as described for the rotor 200 in FIG. 17.
FIG. 19 shows a fragment of a rotor 240 wherein the two rows of pockets 241 are milled to an essentially arcuate contour in axial section, rather than the relatively flat bottoms of the pockets shown in the other views, and cooperate with lands 242. The stator 245 has two rows of similar milled pockets 246 and lands 247. Except for their contour in axial section, the pockets 241 and 246 should substantially conform to the geometry described above in connection with FIG. 8, and this configuration of pocket can be used in any of the other embodiments of the invention disclosed herein.
FIG. 20 shows a fragment of a rotor 250 having a working face composed of multiple pockets 251 and a circumferential frusto-conical land 252. As shown, the bottom 253 of each pocket 251 is essentially parallel in axial section with the face of the rotor, so that the angle defined by the pocket bottom and the axis of the rotor is the same as angle a in FIG. 8. The stator 255 is of complementary construction, with its working face comprising pockets 256 and a land 257, and with the pocket bottom 258 essentially parallel with the rotor pocket bottom 253. These pockets accordingly conform with the overall geometry ranges noted above in connection with FIGS. 6 and 8, and this pocket configuration could be used in any of the other forms of the invention already described.
While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to their precise forms of apparatus, and that changes may be made therein without departing from the scope of the invention. It is also to be understood that use of the apparatus of the invention is not limited to the treatment of paper making stock, and that the apparatus may be used for the defibering or deflaking of other liquid slurry stocks, for example in the processing of tobacco. | A deflaker for use in defibering coarse paper making stock includes a rotor and stator having frusto-conical working faces, each of which has therein one or more circumferential rows of angularly spaced pockets separated by axially extending land areas and with a circumferential land between adjacent rows of pockets, the proportions and arrangement of the parts being such that the stock is forced to travel back and forth between rotor and stator pockets as it passes through the working zone. The inlet chamber in which the rotor and stator operate is of substantially larger diameter to provide outlying space to which high specific gravity contaminant materials are directed by the centrifugal force generated by the rotor, and this action is enhanced by a cover plate on the inlet end of the rotor which has the dual function of defining with the adjacent end wall of the stator an entry slot to the working zone, and of developing additional centrifugal force further tending to prevent high specific gravity contaminant materials from reaching this inlet slot. The working faces of the rotor and stator are axially symmetrical so that the rotor can be driven in either direction to double the working life of these elements, and when it is necessary to remove and replace any of the working elements, this can be done without disturbing any piping connections by simply removing a cover plate which forms one wall of the inlet chamber. | 3 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to substrates such as those used in inkjet printheads and the like.
BACKGROUND OF THE INVENTION
[0002] Various inkjet printing arrangements are known in the art and include both thermally actuated printheads and mechanically actuated printheads. Thermal actuated printheads tend to use resistive elements or the like to achieve ink expulsion, while mechanically actuated printheads tend to use piezoelectric transducers of the like.
[0003] A representative thermal inkjet printhead has a plurality of thin film resistors provided on a semiconductor substrate. A nozzle plate and barrier layer are provided on the substrate and define the firing chambers about each of the resistors. Propagation of a current or a “fire signal” through a resistor causes ink in the corresponding firing chamber to be heated and expelled through the appropriate nozzle.
[0004] Ink is typically delivered to the firing chamber through a feed slot that is machined in the semiconductor substrate. The substrate usually has a rectangular shape, with the slot disposed longitudinally therein. Resistors are typically arranged in rows located on both sides of the slot and are preferably spaced approximately equal distances from the slot so that the ink channel length at each resistor is approximately equal. The width of the print swath achieved by one pass of a printhead is approximately equal to the length of the resistor rows, which in turn is approximately equal to the length of the slot.
[0005] Feed slots have typically been formed by sand drilling (also known as “sand slotting”). This method is preferred because it is a rapid, relatively simple and scalable (many substrates may be processed simultaneously) process. While sand slotting affords these apparent benefits, sand slotting is also disadvantageous in that it causes micro cracks in the semiconductor substrate that significantly reduce the substrates fracture strength, resulting in significant yield loss due to cracked die. Low fracture strength also limits substrate length which in turn adversely impacts print swath height and overall print speed.
[0006] Other techniques include ultrasonic diamond bit drilling, abrasive sand blasting, YAG laser machining, KOH etching, TMAH etching, and dry plasma etching.
[0007] Ultrasonic diamond bit drilling is only suited for machining round holes. Moreover, this process creates large chips to glass and silicon on both the input and output side of the through hole. These chips are too large (hundreds of microns) to allow the resistors to be close to the ink feed slot.
[0008] Abrasive sand blasting also has chipping problems, due to chipping of the wafer around the output side of the through slot. This chipping causes two separate issues. Normally the chipping is tens of microns large and limits how close the firing chamber can be placed to the edge of the slot. Occasionally the chipping is larger and causes yield loss in the manufacturing process. The chipping problem is more prevalent as the desired slot length increases and the desired slot width decreases. In this process the resulting shape of the slot is controlled by many factors. The variation of the slot edge position causes variation on the ink flow resistance. The slot position is controlled mechanically in a harsh environment, thus limiting the accuracy and repeatability of the slot positioning to about +/−15 microns.
[0009] YAG laser machining also has disadvantages. The laser system is expensive to buy and maintain. The relatively small laser beam needs to be “paned,” i.e. moved, around the parameter of the desired slot area and needs multiple passes to cut through the wafer. The laser produces a small spot (around 10 to 50 microns in diameter) where the laser energy is focussed. This small active area requires that the laser spot be moved around the perimeter of the area that is to be cut while the laser is pulsed. It takes many laser pulses at each perimeter location to cut through the silicon wafer, which in an exemplary embodiment has a nominal thickness of 670 microns. Typical water processing time is 2 to 3 hours, limiting system capacity. As the laser burns through the silicon there is an area around the cut where the silicon is melted, not vaporized. This molten silicon is spattered around the edge of the drill slot causing problems with part adhesion and leaving globules or slag that can later break loose and clog the ink feed path. The area around the laser cutting zone gets hot enough to cause damage to the thinfilm and barrier material.
[0010] KOH (Potassium hydroxide) etching can damage the thin films, since KOH is a corrosive basic chemical which will etch silicon, and will attack the thinfilms used in many types of inkjet printheads. To avoid the KOH etch attack of the thinfilms, the etch process needs to occur prior to the thinfilm processing. This processing order causes problems because trenched wafers can not be handled by many of the thinfilm processing tools. For an anisotropic etch, the etch rate is different for different crystalline planes; therefor the etch geometry is defined by the crystalline planes. Etch angles cause the backside opening of a slot to be very large and limit how close the slots can be placed to each other and the edge of the die.
[0011] TMAH (Tetra Methyl Ammonium Hydroxide) is another anisotropic etchant for silicon. TMAH etching techniques on <100> silicon employ etch angles causing the backside opening of a slot to be very large, and thus limit how close the slots can be placed to each other and the edge of the die. An anisotropic etch, the TMAH etch rate is different for different crystalline planes, and therefore the etch geometry is defined by the crystalline planes. Etch rates are only about 1 micron per minute. Typical wafer etch rates are about 8 hours if etched from both sides and 12 hours if etched from one side. Wafers can be batch processed. The masking films are drastically undercut as a result of the extended etching time. These films can break and become a mobile contaminant that can block ink flow in the pen. The etch blocking oxides around the edge of the wafer are scraped and damaged during wafer handling. Where the oxide layer on the wafer has been damaged, etching occurs, causing problems for wafer fragility and handling in subsequent process steps. Slots in the wafer causes thinning of the barrier material.
[0012] Dry plasma etching techniques utilize relatively slow etch rates. Etch rates are only about 2 micron per minute. Typical wafer etch rates are about 3 hours if etched from both sides and 6 hours if etched from one side. Wafers can not be batch processed. Long etches cause damage to thinfilms that are used in inkjet. Dry plasma etchers are very expensive. Slots in the wafer causes thinning of the barrier material.
SUMMARY OF THE INVENTION
[0013] A method of fabricating an inkjet printhead is described, and includes providing a printhead substrate, fabricating a thinfilm structure on the substrate, forming a break trench in a surface region of the substrate in which a feed slot is to be formed, and subsequently abrasively machining the substrate through the break trench to form the feed slot.
[0014] In accordance with an aspect of the invention, the break trench is formed by an etch process. The etch process is performed prior to applying a barrier layer to the thinfilm structure in a preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWING
[0015] These and other features and advantages of the present invention will become more apparent from the following detailed description of exemplary embodiments thereof, as illustrated in the accompanying drawings, in which:
[0016] FIG. 1A is a top plan view of the printhead structure after the first step of the printhead fabrication process, i.e. after the inkjet thin film structure has been formed on the silicon substrate. FIG. 1B is a cross-sectional view of the printhead structure of FIG. 1A after a further step of the fabrication process, the TMAH etch process, has been performed to create a slot break trench.
[0017] FIG. 2A illustrates in top plan view the top of the substrate after the thin film fabrication step on the substrate, for a first alternate embodiment of the fabrication process. FIG. 2B is a cross-sectional view of the printhead structure of FIG. 2A , after the TMAH etch process has been performed for this alternate embodiment.
[0018] FIG. 3A illustrates in top plan view for a second alternate embodiment of a printhead fabrication process the top of the substrate after the thin film fabrication step on the substrate. FIG. 3B is a cross-sectional view of the printhead structure of FIG. 3A , after the TMAH etch process has been performed to create a break trench.
[0019] FIG. 4A illustrates in top plan view for a third alternate embodiment of a printhead fabrication process the top of the substrate after the thin film fabrication step on the substrate. FIG. 4B is a cross-sectional view of the printhead structure of FIG. 4A , after the TMAH etch process has been performed to create a break trench and after the barrier layer is applied.
[0020] FIG. 5A illustrates in top plan view for a fourth alternate embodiment the top of the substrate after the thin film fabrication step on the substrate. FIG. 5B is a cross-sectional view of the printhead structure of FIG. 5A taken along line 5 B- 5 B of FIG. 5A , after the TMAH etch process has been performed to create a break trench and after the barrier layer is applied. FIG. 5C is a cross-sectional view of the printhead structure of FIG. 5A taken along line 5 C- 5 C of FIG. 5A , after the TMAH etch process has been performed to create a break trench and after the barrier layer is applied.
[0021] FIG. 6A diagrammatically depicts in a top view of a substrate a further embodiment, wherein trenches serving as chip stop bars are not connected at the corners. FIG. 6B is a cross-sectional view taken along line 6 B- 6 B of FIG. 6A .
[0022] FIG. 7A illustrates in a top view a further embodiment of a break trench process, similar to the embodiment of FIG. 6A , except that the top and bottom chip stop bars are omitted. FIG. 7B is a cross-sectional view taken along line 7 B- 7 B of FIG. 7A .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] An exemplary embodiment of a process in accordance with aspects of this invention uses the thinfilm materials and processes heretofore employed in inkjet printhead construction. The changes to this process involve the redesign of the artwork on the photomask set to allow for the silicon wafer to be uncovered in the desired area for a TMAH (Tetra Methyl Ammonium Hydroxide) etching of the trenches in accordance with this aspect of the invention. TMAH is an anisotropic etchant for silicon. For an anisotropic etch, the etch rate is different for different crystalline planes, and thus the etch geometry is defined by the crystalline planes. This etching of the trenches happens after the thinfilm processes are complete and before the barrier material is applied. This TMAH etch process includes a few short steps:
[0024] 1. Wafer Surface cleaning in the Backside Oxide Etch (BOE).
[0025] 2. De-ionized water Rinse.
[0026] 3. TMAH Etching.
[0027] 4. De-ionized water Rinse.
[0028] The wafers are then subjected to the current processing to complete the pen construction. The abrasive drill process is tuned to match the shape and size required to work with the trench design. A simplified process flow for creating the printhead is shown below for each process.
[0029] 1. Create Inkjet Thinfilm Structure
[0030] 2. Perform TMAH Etch Process
[0031] 3. E-test Thinfilm
[0032] 4. Apply and Pattern Barrier
[0033] 5. Create Inkfeed Slot with Abrasive Machining
[0034] 6. Attach Orifice
[0035] 7. Saw Wafer
[0036] 8. Attach Printhead to Flex Circuit
[0037] Steps 1 and 3-8 are the steps in the state of the art process described above. Step 2 is the new trench etch step described above.
[0038] Aspects of the invention solve several problems, including the following. The chipping that is normally caused by the abrasive machining process is contained and stopped by the parameter etch trench. In many cases, the etch trench defines the crack location site. Therefore the slot edge can be moved closer to the resistor to give a faster ink refill rate along with a low scrap rate regardless of slot width and length.
[0039] The slot or trench shape can be accurately and repeatedly defined through a photolithography process and the crystalline planes of the silicon which define the trench shape. TMAH has dramatically different etch rates for the different crystalline planes. Due to this fact, for an etching from the b < 100 > plane at the surface of the silicon wafer, the etch will proceed down into the wafer until it reaches the <111> plane. The <111>l plane is at a 53 degree angle to the <100> plane, and will therefore etch a “V” shaped notch in cross section. On the <100> plane, the <111> planes intersect at 90 degree angles, and therefore square or rectangular patterns can be readily formed to the molecular level with trenches having the “V” trench cross-section. The photolithography process which defines the trench position also allows the trench slot edge positions to be accurately and repeatedly placed.
[0040] The etched silicon trenches are shallow and etch relatively quickly. Typical wafer etching time is 20-50 minutes for a batch of 25 wafers. Typical wafer abrasive drill time is 50-70 minutes. The etch times are short enough that no significant damage occurs to the wafer edge. This process does not create sufficient heat to cause damage to surrounding thinfilms or inkjet materials.
[0041] Barrier thinning is minimized by the narrow and relatively shallow etched trench used by this process technology. The TMAH etch and relatively short etch times prevent damage to the thinfilms on the inkjet printhead. Control of the chipping outside of the etched trench minimizes thinfilm damage due to chipping.
[0042] Several exemplary trench designs are illustrated in FIGS. 1A-7 , in which like reference numbers refer to like elements, and described below.
[0043] Break-Trench Slot Embodiment ( FIGS. 1A-1B )
[0044] In the break-trench embodiment, a v-trench is etched around the perimeter of the ink feed slot area prior to the abrasive drill process. This trench works as a crack initiation site to control the breakthrough location for the abrasive machining, in this embodiment, an abrasive drill process. In addition, this trench stops the propagation of the shallow chipping experienced with the abrasive drill process.
[0045] FIG. 1A is a top plan view of the printhead structure 100 after the first step of the fabrication process, i.e. after the inkjet thin film structure has been formed on the silicon substrate. FIG. 1B is a cross-sectional view of the printhead structure 100 after the TMAH etch process has been performed to create a break trench and after the barrier layer 112 is applied.
[0046] The printhead structure 100 includes a silicon substrate 102 on which various patterned layers have been formed to fabricate the thin film structure, shown generally as 101 in FIG. 1B . The thin film structure details will vary in dependence on the particular printhead design. FIGS. 1A-1B illustrate in simplified form some of the patterned layers defining an exemplary thin film structure. These include a field oxide layer 104 , a polysilicon layer 106 , a passivation layer 108 including silicon carbide and silicon nitride layers, a tantalum layer 110 to define heating resistors for the printhead. Not shown, for example is an aluminum layer defining wiring traces.
[0047] The location of the desired feed slot for the printhead is indicated by dashed line 120 in FIG. 1A , which marks the periphery of the desired slot. The printhead material within this line 120 is to be removed to provide the feed slot for the printhead. The field oxide (FOX) layer in the area of the feed slot will serve as a mask for the TMAH etching, and has been removed in the region 122 about the line 120 , in preparation for the TMAH trench etch process. The FOX layer is typically removed to obtain substrate contacts to the silicon in the thermal inkjet fabrication process. However, in the past, the FOX layer has remained in the ink feed slot area. TMAH will not etch the FOX layer, and thus the FOX needs to be selectively removed to allow the etching of the silicon substrate to occur. The photomask design for the contact etch is changed, from the prior design, so that the FOX will be removed for the substrate contacts and the break trench at the same time. This area is then kept open throughout the remaining thinfilm processing before going through the TMAH etch process to create the breaktrench.
[0048] Alternatively, instead of using the FOX layer as the mask for the TMAH etching process, the passivation layer (SiN/SiC) can be employed for this purpose. In one exemplary alternate embodiment, this passivation layer is extended so that it overlaps the edge of the FOX layer by about 3 microns.
[0049] After the TMAH etch process, a break trench 124 ( FIG. 1B ) is formed in the substrate 102 . In an exemplary embodiment, the trench is 80 microns wide to a target depth of 58 microns, although the width and depth of the trench may be different for different slot sizes or applications. Now the remaining steps 3-8 in the fabrication process can be performed. These include the electronic testing of the thin film structure, and the application and patterning of the barrier layer 112 ( FIG. 2B ). The barrier layer is typically a polymer layer.
[0050] After the barrier layer is fabricated on the printhead structure, the ink feed slot is created by abrasive machining, in this case by abrasive drilling from the underside of the substrate 102 (opposite side from the thinfilm layer side) along a drill slot 126 . The abrasive drilling process in an exemplary embodiment utilizes a sand blasting system that mixes a fine aluminum oxide abrasive into a high-pressure air stream. This mixture of abrasive and air is then plumed to a nozzle that is sized and shaped to create the desired cut profile in the substrate. The abrasive drilling cutting time, cutting pressure and nozzle separation for the silicon substrate is adjusted to obtain an appropriate slot through the silicon substrate.
[0051] The drill slot 126 preferably enters the bottom of the trench 14 . Now the substrate material enveloped within the drill slot, indicated in FIG. 1A as 102 A, is completely separated from the remainder of the substrate, and can be removed to create the feed slot for the printhead.
[0052] Now the printhead structure 100 can be passed through the remaining fabrication steps, including attachment of the orifice plate, wafer sawing and the attachment of the printhead to a flexible circuit, typically a TAB circuit, for attachment to a printhead pen body.
[0053] Break-Trench and Drill Guide Trench Slot Embodiment ( FIGS. 2A-2B )
[0054] In this embodiment, the initial breakthrough occurs along a deeper “drill guide” trench and then grows out to the perimeter etch trench. The perimeter etch trench is used primarily as a chip stop feature. Thus, with this process, the sand slotting process will first break through the wafer at the location of the center trench. The sand slotting will then be continued until the through slot has grown to the size of the outer break-trench A chip stop feature is one that will stop the propagation of shallow chips by allowing them to be terminated by breaking through the inside wall of the trench. When the chips or cracks break through the inside wall, the chip will stop as it can not propagate the stress through the gap.
[0055] FIG. 2A illustrates in top plan view the top of the substrate 102 after the thin film fabrication step on the substrate. The structure illustrated in FIG. 2A is similar to that shown in FIG. 1A , but the field oxide layer in the center of the location of the feed slot is also removed, so that the silicon substrate surface is also exposed at 122 A. The TMAH trench etch process is then performed, to define a perimeter etch trench 134 which follows the outline of dashed line 120 ( FIG. 2A ), as well as a deeper drill guide trench 132 in the central region 122 A. In an exemplary embodiment, the perimeter trench is approximately 60 microns wide by 43 microns deep at its maximum depth, and the drill guide trench is approximately 80 microns wide by 53 microns deep at its maximum depth.
[0056] The width of the etch mask will determine the terminal depth of the trenches produced by the TMAH. This is due to the low etch rate of the <111> plane in the silicon crystalline structure. The shallow perimeter trench will reach a stopping point when the <111> planes terminate in a sharp “V”. The wider center trench will not have reached this termination point and will continue to etch at the higher etch rate.
[0057] After the TMAH etch process has been performed, and the two trenches 132 , 134 formed, as illustrated in FIG. 2B , the remaining steps in the fabrication process are performed. The abrasive drilling occurs along drill slot 136 , and an initial breakthrough of the silicon substrate 50 occurs along the deeper drill guide trench 132 . The removal of material then grows out to the perimeter etch trench 134 . The size of the through trench will be determined by the mechanical sand slotting process.
[0058] Center-Trench Full Slot Embodiment ( FIGS. 3A-3B )
[0059] In this embodiment, the abrasive drill slot is small enough to be placed in the center of the TMAH etch trench, and the sloped sides of the trench are used to contain the chipping and define the slot shape and position.
[0060] FIG. 3A illustrates in top plan view the top of the substrate 102 after the thin film fabrication step on the substrate. FIG. 3B shows in cross-section the substrate 102 after the TMAH etch process has been performed, and after the barrier layer 112 has been applied. The structure illustrated in FIG. 3A is similar to that shown in FIG. 1A , but the field oxide layer 104 in the location of the feed slot is also removed to near the edges, leaving border region 104 C of the field oxide layer, so that the silicon substrate surface is also exposed at area 156 . The TMAH trench etch process is then performed, to define an etch trench 152 which follows the outline of dashed line 120 ( FIG. 3A ).
[0061] After the TMAH etch process has been performed, and the trenches 152 formed, the remaining steps in the fabrication process are performed. The abrasive drilling occurs along drill slot 154 , and the removal of material inside the drill slot provides the ink fill slot. This embodiment can provide a narrower fill slot than the first two embodiments in some applications.
[0062] Center-Trench Multiple Slot Embodiment ( FIGS. 4A-4B )
[0063] This embodiment is similar to the center trench embodiment described with respect to FIGS. 3A-3B , but multiple small slots are employed so that additional silicon is left in the center of the printhead die to increase die strength.
[0064] FIG. 4A illustrates in top plan view the top of the substrate 102 after the thin film fabrication step on the substrate. FIG. 4B is a cross-sectional view of the printhead structure 170 after the TMAH etch process has been performed to create a break trench and after the barrier layer 112 is applied. The structure illustrated in FIG. 4A is similar to that shown in FIG. 3A , with the field oxide layer 104 in the location of the feed slot removed to near the edges, leaving border region 104 C of the field oxide layer. Dashed lines 172 A- 172 D indicate the desired perimeters of the multiple ink feed slots. The TMAH trench etch process is then performed, to define one etch trench in the region 178 .
[0065] After the. TMAH etch process has been performed, and the trench 174 formed, the remaining steps in the fabrication process are performed. The abrasive drilling occurs along a drill slot for each slot location 172 A- 172 D, including drill slot 176 C for slot location 172 C, and the removal of material inside the drill slots provides the multiple slots. Thus, a nozzle with a plurality of slots fed from a single source would be produced to drill the desired pattern in a single process step. In an exemplary embodiment, the small rectangular openings are approximately 200 microns wide by 1500 microns long, with 1500 microns spacing between the nozzle openings. Therefore the nozzle produces a series of smaller slots.
[0066] Island Trench Multi-Slot Embodiment (FIGS. 5 A-SC)
[0067] In this design, Islands are left between the ink feed slots to help support the barrier, give additional die strength and promote the removal of air bubbles. The wedge shape of the island to slot edge forces the air bubbles towards the ink feed slots as they grow.
[0068] FIG. 5A illustrates in top plan view the top of the substrate 102 after the thin film fabrication step on the substrate. FIG. 5B is a cross-sectional view of the printhead structure 190 after the TMAH etch process has been performed to create a break trench and after the barrier layer 112 is applied. The structure illustrated in FIG. 5A is similar to that shown in FIG. 4A , except that pyramid-shaped islands 104 D 1 - 104 D 3 of the field oxide layer 104 are left in the feed slot area. These islands will mask the underlying areas of the silicon substrate from the TMAH etching process. Dashed lines 172 A- 172 D indicate the desired perimeters of the multiple ink feed slots.
[0069] The TMAH trench etch process is then performed, to define a patterned etch trench 192 in the region 178 .
[0070] After the TMAH etch process has been performed, and the trench 192 formed, the remaining steps in the fabrication process are performed. When the barrier layer 112 is applied, the barrier will cover the pyramid-shaped islands 104 D 1 - 104 D 3 , as indicated in FIG. 5C . The abrasive drilling occurs along a drill slot for each slot location 172 A- 172 D, including drill slot 176 C for slot location 172 C, and the removal of material inside the drill slots provides the multiple slots.
[0071] The island trench design uses different artwork on the FOX (hardmask) level to pattern islands in the center of the ink feed slot area. This photomask is designed to leave pyramid shaped islands in the center of the ink feed slot area, as shown in FIG. 5A . As in the foregoing embodiments, the barrier layer is then laminated and patterned, and in this case the barrier layer material is left covering the top of the pyramid-shaped islands to help support the orifice plate that is applied at a later time. The drill process is performed as in the embodiment of FIGS. 4A-4B , in that a number of small through slots are created between the islands as shown in FIG. 5B . The through slots in cross-section have a shallow trench at the center of the island that becomes deeper and wider as it approaches the cross-section at 5 B- 5 B.
[0072] Chip Stop Bars
[0073] FIGS. 6A-6B diagrammatically depict a further embodiment, wherein trenches serving as chip stop bars are not connected at the corners. FIG. 6A is a diagrammatic top view of the substrate 220 after fabrication step 2, i.e. after the silicon substrate with the thinfilm layers have been subjected to the TMAH etching process, to form side trenches 226 A, 226 B and top and bottom trenches 228 A, 228 B. The drill slot is indicated by dashed line 222 . All substrate within line 222 is to be removed during the abrasive machining process conducted along drill slot 232 ( FIG. 6B ) to form the feed slot. In an exemplary embodiment, the side trenches are 80 microns wide by 8300 microns long, and the top and bottom trenches are 160 microns wide by 80 microns high. The separation of the side trenches, outside to outside, is 260 microns; the separation of the top and bottom trenches, outside to outside, is 8480 microns. The trenches have a target depth of 58 microns for this embodiment.
[0074] Field oxide layer regions 104 A and 104 E 1 -E 4 ( FIG. 6A ) provide separation definition between the side trenches 226 A- 226 B and the top and bottom trenches 228 A- 228 B.
[0075] The embodiment of FIG. 6A provides several advantages. Barrier thinning differences between the slot center and ends should be reduced, since the trench at the ends of the slot would not etch as deeply or as wide as in the embodiment of FIG. 1A . Protection from die chipping is still in place on all sides of the die. A possible disadvantage is that the increased number of sharply etched corners may lead to reduced die strength.
[0076] Side Trench Design
[0077] FIGS. 7A-7B illustrate a further embodiment of a break trench process, similar to the embodiment of FIGS. 6A-6B , except that the top and bottom chip stop bars are omitted. FIG. 7A is a diagrammatic top view of the substrate 240 after fabrication step 2, i.e. after the silicon substrate with the thinfilm layers have been subjected to the TMAH etching process, to form side trenches 246 A, 246 B. As in FIG. 6A , the nominal drill slot is indicated by dashed line 222 , and in an exemplary embodiment this feature can have the same nominal size as indicated above for the exemplary embodiment described regarding FIG. 6A . For the substrate 240 , only the side chip stop bars 246 A, 246 B are employed, and are separated by FOX layer region 104 F ( FIG. 7A ) . Thus, etch trenches are provided at both sides of the slot area, but no etch trenches are provided at the top and bottom of the slot. In one exemplary embodiment, the side trenches can have a width of 80 microns and a length of 8430 microns. In another exemplary embodiment, the trenches are left somewhat short of the end of the slot to provide increased die strength, and have a length of 8100 microns. The substrate material within line 222 is to be removed during the subsequent abrasive machining process conducted along drill slot 250 ( FIG. 7B ).
[0078] It is understood that the above-described embodiments are merely illustrative of the possible specific embodiments which may represent principles of the present invention. Other arrangements may readily be devised in accordance with these principles by those skilled in the art without departing from the scope and spirit of the invention. | Techniques for fabricating an inkjet printhead include providing a printhead substrate, fabricating a thinfilm structure on the substrate, forming a break trench in a surface region of the substrate in which a feed slot is to be formed, and subsequently abrasively machining the substrate through the break trench to form the feed slot. The break trench can be formed by an etch process, prior to applying a barrier layer to the thinfilm structure in a preferred embodiment. | 1 |
BACKGROUND
A unique Scandinavian tradition is the creation of baskets for hanging on a Christmas tree. These baskets were created of paper that was cut and woven together to form a basket in which treats could be stored. The paper baskets were generally in the shape of hearts. The heart shaped baskets symbolized the love and beauty of Christmas while displaying an individuals' artistic flair.
For years, people have been displaying bumper stickers and other emblems on their vehicles (or other foreign objects) to show their support for a cause, support a candidate running for office, or to say something funny. However, once the bumper stickers have been applied to the surface of the object, they are difficult to remove. In some cases, the stickers have ruined the surface of the object to which they are applied.
What is needed in the art is a device that is easily removable from a surface, without ruining the surface, while still conveying an individual's viewpoint.
SUMMARY
The disclosure is directed toward a woven magnetic device. The woven magnetic device comprises a first member having a body with a top portion and a bottom portion opposite the top portion and the bottom portion has at least two fingers. The woven magnetic device also comprises a second member having a body with a top portion and a bottom portion opposite the top portion. The bottom portion has at least two fingers interwoven with the at least two fingers of the first member. The first member and the second member comprise a magnetic material.
The disclosure is also directed toward a method for making a woven magnetic device. The method comprises producing a first member having a body with a top portion and a bottom portion opposite the top portion and the bottom portion has at least two fingers. The method also comprises weaving at least two fingers of a second member with the at least two fingers of the first member. The second member has a body with a top portion and a bottom portion opposite the top portion and the bottom portion has the at least two fingers. The first member and the second member comprise a magnetic material.
BRIEF DESCRIPTION OF THE FIGURES
Referring now to the figures, wherein like elements are numbered alike:
FIG. 1 is a perspective view of a first member of an exemplary woven magnetic device;
FIG. 2 is a perspective view of a second member of an exemplary woven magnetic device;
FIG. 3 is a perspective view of the first member being woven with the second member to form an exemplary woven magnetic device;
FIG. 4 is a perspective view of an exemplary embodiment of the woven magnetic device;
FIG. 5 is a perspective view of a third member of another exemplary woven magnetic device;
FIG. 6 is a perspective view of the first member of FIG. 1 being woven with the third member to form another exemplary woven magnetic device;
FIG. 7 is a perspective view of another exemplary embodiment of the woven magnetic device;
FIG. 8 is a perspective view of two members utilized to create another exemplary embodiment of the woven magnetic device incorporating a design;
FIG. 9 is a perspective view of another exemplary embodiment of the woven magnetic device incorporating a design; and
FIG. 10 is a perspective view of another exemplary embodiment of the woven magnetic device incorporating a design.
DETAILED DESCRIPTION
Persons of ordinary skill in the art will realize that the following disclosure is illustrative only and not in any way limiting. Other embodiments of the invention will readily suggest themselves to such skilled persons having the benefit of this disclosure.
The present invention is a woven magnetic device that has an overall shape of a heart. The woven magnetic device adheres to metal objects and is removable. The woven magnetic device does not require additional adhesives to create the overall effect, since the magnetic material adheres to itself. The woven magnetic device can be displayed alone or can display support for a cause or convey a belief. The weaving of the magnetic material provides a three dimensional appearance to the woven magnetic device, which is desirable to an individual looking to make a statement.
A preferred embodiment is illustrated in FIG. 1 . A first member 10 includes a body 12 . The first member 10 body 12 has a top portion 14 and a bottom portion 16 . The top portion 14 can be of any shape, with a rounded configuration preferred, although other configurations are contemplated, as illustrated and further described in FIG. 8 . The bottom portion 16 is configured to have fingers 18 , 20 , 22 , 24 , 26 . The fingers are of equal length. Although five fingers are illustrated, any number of fingers may be utilized depending upon the intricacies of the design desired.
Referring now to FIG. 2 , a second member 28 is illustrated. The second member 28 includes a body 30 . The second member 28 body 30 has a top portion 32 and a bottom portion 34 . The top portion 32 can be of any shape, with a rounded configuration preferred, although other configurations are contemplated, as illustrated and further described in FIG. 8 . The bottom portion 34 is configured to have fingers 36 , 38 , 40 , 42 , 44 . The fingers are of equal length and shape. Although five fingers are illustrated, any number of fingers may be utilized depending upon the intricacies of the design desired. In each case, when weaving, the two members 10 , 28 should be the same, having an equal number, shape and length of fingers. The shape of the members and fingers may vary depending upon the design or pattern desired, as will be discussed further herein. It is also preferable for the first member 10 and the second member 28 to be two different colors, although one or any number of colors can be utilized, as will be discussed further herein.
It is also contemplated to cut the fingers on an angle (i.e., 45 degrees) to enhance the effect of the woven magnetic device on the viewer. By creating a beveled (or biased or cater-cornered or skewed or slanted or transversal) edge of the fingers, the woven magnetic device takes on a three-dimensional appearance which is visually appealing.
The size of the first member 10 and the second member 28 can vary depending upon the desired size of the resulting woven magnetic device. A preferred length of the first member 10 and the second member 28 is about 3.0 inches to about 8.0 inches, with about 3.8 inches to about 4.2 inches preferred. The width of the first member 10 and the second member 28 can be about 2.25 inches to about 5.5 inches, with about 2.5 inches to about 3.0 inches preferred. The length of the fingers can be about 2.0 inches to about 5.5 inches, with about 2.5 inches to about 2.7 inches preferred. The width of the fingers can be about 0.4 inches to about 1.0 inches, with about 0.42 inches to about 0.52 inches preferred.
When creating designs, as further explained herein, the width of the fingers will vary depending upon the desired design (See FIG. 8 ).
The first member 10 and the second member 28 comprise a piece of ferromagnetic or ferromagnetic material whose domains are sufficiently aligned so that it produces a net magnetic field outside itself and can experience a net torque when placed in an external magnetic field. The material can be iron, iron alloys, nickel, nickel alloys, cobalt, cobalt alloys, and combinations thereof. The magnetic material can have a thickness of about 0.02 inches to about 0.04 inches, with about 0.025 inches to about 0.035 inches preferred. The thickness of the material is dependent upon the type of material, and the use and size of the woven magnetic device.
Referring to FIG. 3 , an illustration of the weaving (or braiding or interlacing or lacing or intertwining or plaiting or entwining or merging or uniting or interweaving) of the first member 10 with the second member 28 in order to form an exemplary woven magnetic device is presented. In order to create the woven magnetic device, the first member 10 must be woven with the second member 18 . To start, freely movable finger 18 is woven through the fingers 44 , 42 , 40 , 38 , 36 of the second member 28 . At the base 46 of the fingers 36 , 38 , 40 , 42 , 44 of the second member 28 , finger 18 of first member 10 is disposed over finger 44 and then under finger 42 and then over finger 40 and then under finger 38 and finally over finger 36 . Next, finger 20 is disposed under finger 44 and then over finger 42 and then under finger 40 and then over finger 38 and finally under finger 36 . This process is repeated with each remaining finger (i.e., fingers 22 , 24 , 26 ) to create a woven pattern as illustrated in the magnetic woven device 48 in FIG. 4 . It is not important which member is utilized to start the weaving process, as long as the two members are braided together as described above. No adhesive is necessary to hold the fingers in place since the magnetic material adheres to itself. The first member 10 and the second member 28 are attracted to each other because of the magnetic property of the material and can be removable from each other with little force.
Another embodiment is illustrated in FIGS. 5 , 6 , and 7 . In FIG. 5 , a third member 50 includes a body 52 . The third member 50 body 52 has a top portion 54 and a bottom portion 56 . The top portion 54 can be of any shape, with a rounded configuration preferred, although other configurations are contemplated, as illustrated and further described in FIG. 8 . The bottom portion 56 is configured to have fingers 58 , 60 , 62 , 64 , 66 . However, the fingers are not freely movable. The fingers are defined by the existence of slots (or openings) 68 disposed vertically along the bottom portion 56 creating interlocking fingers. The slots 68 are of sufficient length and width to receive the fingers of a mating member (i.e., first member 10 ). The slots 68 disposed at the end 70 of the bottom portion 56 are open for ease in receiving the final finger. The fingers are of equal length and shape. Although five fingers are illustrated, any number of fingers may be utilized depending upon the intricacies of the design desired.
Referring now to FIG. 6 , an illustration of the weaving (or braiding) of the first member 10 with the third member 50 in order to form an exemplary woven magnetic device is presented. In order to create the woven magnetic device, the first member 10 must be woven with the third member 50 utilizing the slots 68 . To start, finger 18 is woven through the fingers 66 , 64 , 62 , 60 , 58 of the third member 50 . At the base 72 of the fingers 58 , 60 , 62 , 64 , 66 of the third member 50 , finger 18 of first member 10 is disposed over finger 66 fed down through the first slot 68 to be under finger 64 , then finger 18 is fed up through the next slot 68 and then over finger 62 , then finger 18 is fed down through the next slot 68 to be under finger 60 and then finger 18 is fed up through the final slot 68 and positioned over finger 58 . Next, finger 20 of first member 10 is disposed under finger 66 and fed up through the first slot 68 to be over finger 64 , then finger 18 is fed down through the next slot 68 and then under finger 62 , then finger 18 is fed up through the next slot 68 to be over finger 60 and then finger 18 is fed down through the final slot 68 and positioned under finger 58 . This process is repeated with each remaining finger (i.e., fingers 22 , 24 , 26 ) to create a woven pattern as illustrated in the magnetic woven device 74 in FIG. 7 . In each case, when weaving it is ideal to have the two members 10 , 50 be of the same shape, with one of the members having slots instead of freely movable fingers. The shape of the members and fingers may vary depending upon the design or pattern desired, as will be discussed further herein. As stated above, no adhesive is necessary to hold the fingers in place since the magnetic material adheres to itself.
As illustrated in FIG. 8 , other woven designs are contemplated. The intricacies of the designs are dependent upon the manner of weaving, the number of fingers, the size of the fingers, the colors of the fingers, the designs on the fingers, and the desired pattern. It is contemplated to create curved fingers, fingers having specific shapes (i.e., cut-outs or jutting portions) to create a design or figure (i.e., hearts, stars, trees, crests, faces, people, etc.) within the woven magnetic device. For example, FIG. 8 illustrates a first member 76 and a second member 78 that can be woven as described above (illustrated using arrow 80 ) to create the woven magnetic device 82 having a design element 84 incorporated therein. In this case, the design element 84 is a pinwheel shape. Any design elements are contemplated as long as the fingers can be shaped to create a specific design.
The members may be of different colors or have graphics disposed on them so as to create a colorful device or a specific design once woven, as illustrated in FIGS. 9 and 10 . FIGS. 9 and 10 illustrate the use of graphics. Woven magnetic device 86 is colored green and when woven will display a white VT 88 (i.e., the abbreviation for Vermont). Likewise, magnetic woven device 90 is colored to resemble an American flag (i.e., red, white, and blue) so the red stripes 92 and white stripes 94 are woven together. A first top corner 96 of the magnetic woven device 90 is blue with a design of white stars while the second top corner 98 is green having a white VT. Various resulting graphic designs for the woven magnetic device are contemplated including, but not limited to, flags of countries (i.e., the United States, Denmark, Norway, Sweden, Canada, China, Japan, Germany, the Netherlands, Australia, South Africa, etc.), symbols for favorite destinations (VT, BI, etc.), designs for causes (i.e., “Support Our Troops”, the American Heart Association, Downs Syndrome, etc.), advertising for businesses or political candidates, funny sayings, inspirational sayings, driving messages, and messages of love.
The woven magnetic device provides an aesthetically pleasing means for an individual to convey messages to others. The design of the woven magnetic device ensures that the object to which it is applied is not damaged. Further, the properties of the magnetic material lend to the ability of the woven members to adhere to each other.
While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention. | A woven magnetic is disclosed. The woven magnetic device comprises a first member comprising a magnetic material and having a body with a top portion and a bottom portion opposite the top portion and the bottom portion has at least two fingers. The woven magnetic device also comprises a second member comprising a magnetic material and having a body with a top portion and a bottom portion opposite the top portion. The bottom portion has at least two fingers interwoven with the at least two fingers of the first member. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The field of invention relates to arrow storage structure, and more particularly pertains to a new arrow storage container wherein the same is arranged for the mounting of arrows within a rigid container structure.
2. Description of the Prior Art
Arrow holders of various types are indicated in the prior art and exemplified by the U.S. Pat. Nos. 5,011,028; 3,563,549; 5,085,319; 3,896,782; and 4,621,606.
The instant invention attempts to overcome deficiencies of the prior art by providing for a container arranged to store and secure arrows during their transport without damaging the delicate retching forming a part thereof and, in this respect, the present invention substantially fulfills this need.
SUMMARY OF THE INVENTION
In view of the disadvantages inherent in the known types of arrow storage apparatus now present in the prior art, the present invention provides an arrow storage container wherein the same is arranged to include a plurality of spaced parallel tubes to store arrows therewithin. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new arrow storage container apparatus and method which has many of the advantages of the prior art listed heretofore and many novel features that result in a arrow storage container which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof.
To attain this, the present invention provides a container for the storage of arrows in a parallel relationship to afford protection to the arrows prior to use. Individual parallel tubes are mounted rigidly within a container structure to individually receive arrows therewithin. The container helps protect the delicate fletching of the arrows during their storage.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
Those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new arrow storage container apparatus and method which has many of the advantages of the prior art listed heretofore and many novel features that result in a arrow storage container which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof.
It is another object of the present invention to provide a new arrow storage container which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new arrow storage container which is of a durable and reliable construction.
An even further object of the present invention is to provide a new arrow storage container which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such arrow storage containers economically available to the buying public.
Still yet another object of the present invention is to provide a new arrow storage container which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
It is a further object of the present invention to provide a new arrow storage container comprising individual parallel tubes mounted rigidly within a container structure to individually receive arrows therewithin and to protect the delicate retching of the arrows during their storage.
It is yet still a further object of the present invention to provide a new arrow storage container including resilient inserts each having a central bore with a plurality of radial slots extending from the central bore to an outer periphery thereof to maintain alignment and absorb vibration directed to the container during transport and use.
It is even a further object of the present invention to provide a new arrow storage container including a plurality of storage tubes wherein each lowermost end of the storage tubes is formed with a lubricant and/or rust-preventative impregnated fibrous conical receptacle.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is an isometric illustration of the invention.
FIG. 2 is a cross sectional view, taken along the lines 2--2 of FIG. 1 in the direction indicated by the arrows.
FIG. 3 is a further cross sectional view, taken along the lines 3--3 of FIG. 1 in the direction indicated by the arrows.
FIG. 4 is a even further cross sectional view, taken along the lines FIG. 3 in the direction indicated by the arrows.
FIG. 5 is an enlarged cross sectional illustration of section 5 as set forth in FIG. 3.
FIG. 6 is an isometric illustration, partially in cross section, of the container indicating a rear view thereof.
FIG. 7 is an isometric exploded illustration of portion of the invention as indicated by the circled area in FIG. 6.
FIG. 8 is a cross sectional illustration of the area set forth in FIG. 6.
FIG. 9 is an enlarged isometric illustration of the area labeled 9 as indicated in FIG. 6.
FIG. 10 is a cross sectional view, taken along the lines 10--10 of FIG. 9 in the direction indicated by the arrows.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1-10 thereof, a new arrow storage container embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
More specifically, the arrow storage container 10 of the instant invention comprises a rigid container having a front wall 11, a rear wall 12, a bottom wall 13, and spaced side walls 18 to define a substantially rectangularly-shaped parallelepiped container. At least one hinge and preferably a plurality of hinges 14 (see FIG. 6) are mounted to an uppermost end of the rear wall 12. The hinge or hinges 14 mounts a lid 15 onto an upper periphery defined by the combination of the front wall 11, the rear wall 12, and the side walls 18. The lid 15 includes a latch 16 arranged for securement to a lid lug 17 mounted to the front wall 11. A handle 19, of a generally L-shaped configuration, is integral with the front wall 11 for ease of transport of the structure. In addition and as illustrated in FIG. 6, belt loops 33 may be positioned to upper and lowermost ends of the rear wall to permit securement to a belt structure.
To accommodate an organized arrangement of arrows within the container 10, a first web 20 is fixedly mounted within the container parallel to and coextensive the bottom wall 13, as best illustrated in FIG. 3. A second web 21 is similarly fixedly mounted within the container parallel to the first web 20, with the second web arranged in a spaced orientation between the lid 15 and the first web. The first and second webs 20, 21 orthogonally and integrally mount therethrough a matrix of storage tubes 22 of rigid construction. Each of the storage tubes 22 is dimensioned to receive a conventional arrow shaft 23 therewithin. Typically, each arrow shaft 23 is formed with a conventional arrow head 24, as illustrated in FIG. 5 in phantom. The arrow head 24 may simply rest against the interior surface of the bottom wall 13 as shown, or the container may be provided with a conical receptacle 28. FIG. 8 illustrates the variation of the invention wherein each lowermost end of the storage tubes 22 is formed with a lubricant impregnated fibrous conical receptacle 28. In this manner, the arrows are maintained in a clean operative condition prior to use. In addition, the lubricant may include a rust-preventative for precluding corrosion of sharpened arrowhead in which bare metal is typically exposed.
With reference to FIG. 7, it can be shown that the hinge 14 is constructed of a plurality first hinge cylinders 26 fixedly mounted to the rear wall 12, and a plurality of second hinge cylinders 27 mounted to the lid 15, with each of the second hinge cylinders 27 mounted between spaced first hinge cylinders 26. When the first and second hinge cylinders 26 and 27 are aligned, a slide pin 25 is received through the first and second hinge cylinders 26 and 27. The slide pin 25 is formed with a handle loop 25a at an end of the slide pin for ease of manual grasping and removal of the slide pin to provide ease of access within the structure.
As best illustrated in FIGS. 9 and 10, the upper distal end of each of the storage tubes 22 is formed with a resilient insert 30 having a central bore 31 with a plurality of radial slots 32 extending from the central bore 31 to an outer periphery of the web insert 30 to maintain alignment and accommodate vibration directed to the container during transport and use. The slots 32 allow various arrowheads, such as the arrowhead 24 illustrated in FIG. 5, to pass through the insert 30.
As to the manner of usage and operation of the instant invention, the same should be apparent from the above disclosure, and accordingly no further discussion relative to the manner of usage and operation of the instant invention shall be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A container to provide for the storage of arrows in a parallel relationship is provided to afford protection to the arrows prior to use. Individual parallel tubes are mounted rigidly within a container structure to individually receive arrows therewithin. The container helps protect the delicate fletching of the arrows during their storage. | 8 |
FIELD OF THE INVENTION
The present invention relates to improvements in CMOS circuit technology, and more particularly, to a circuit for increasing the breakdown strength of a CMOS circuit.
BACKGROUND OF THE INVENTION
CMOS circuits are commonly designed for a permissible voltage range of only 5 volts. The technological manufacturing parameters and the geometrical design rules of the individual regions are optimized for this voltage range. However, there are applications for CMOS circuits which lie outside this usual 5 V supply and in which the cost of a separate, stable 5 V supply network would be prohibitive. Such applications are, for example, spatially separated circuits for electronic transducers, sensors, or controllers in industrial or commercial equipment. One important application is the automotive sector with a very unstable on-board system of 12 V or 24 V. It is possible to generate a regulated supply voltage of 5 V on the chip; see, for example, German Patent No. 42 42 989.7-32 to U. Theus and assigned to Deutsche ITT Industries GMBH, the assignee herein. However, this technique increases the amount of chip area required and, hence, the manufacturing costs. In many cases, separate voltage stabilization on the semiconductor chip is not necessary, namely if the circuit itself is relatively insensitive to voltage fluctuations and only few circuit pans require the full breakdown strength.
The following gives a brief survey of the main differences in the breakdown strengths of p- and n-channel transistors. The most critical types are n-channel transistors, whose drain-source breakdown voltage determines the maximum permissible supply voltage. If, however, the heavily n-type doped drain region of the n-channel device is embedded in a lightly doped n-type well for receiving a space-charge region, the maximum permissible drain-source voltage will increase to above 24 V with unchanged manufacturing parameters. A voltage-proof n-channel transistor is thus available.
The p-channel transistor permits a drain-bulk voltage of only -5 V if its channel length is less than 1.2 μm. The maximum permissible drain-bulk voltage increases to at least 12 V if the channel length is greater than 3.75 μm. In the following, the negative sign in the case of the voltage values of the p-channel transistors will be omitted for simplicity, i.e., the values are to be understood as absolute values. If the n-type well (bulk region) of the p-channel transistor is collected to the source electrode, the breakdown strength relates to the drain-source current path in the n-type well. If, on the other hand, the n-type well is connected to another source of potential, the maximum permissible drain-source voltage decreases by the difference in potential between the n-type well and the source electrode.
It is, therefore, the object of the present invention to provide a circuit whereby subcircuits which are at different voltage levels within a CMOS monolithic integrated circuit can be connected together in the simplest possible manner taking into account the desired breakdown strength.
SUMMARY OF THE INVENTION
The present invention is directed to a CMOS circuit having at least a first subcircuit coupled between a first point of potential and a first circuit node, and having a second subcircuit coupled between a second circuit node and a second point of potential, said first and second circuit nodes being coupled together, wherein the improvement in combination therewith, comprises: first circuit means coupled to the first point of potential for converting the first potential to a third potential as a function of the magnitude of said first potential, said third potential being of a value inbetween the first and second potentials; a FET having source, drain, gate and well terminals, said source terminal being coupled to said well terminal and to said first circuit node, said third potential being applied to said gate terminal, said drain terminal being coupled to said second circuit node; wherein said FET, in conjunction with said first circuit means, operates to selectively provide a difference in potential between said first and second circuit nodes, thereby preventing voltage breakdown within said subcircuits.
According to another embodiment of the invention, a Hall-sensor circuit comprises: a first p-channel FET having a well terminal coupled to a source terminal which is coupled to a first circuit node, a drain terminal coupled to a second circuit node, and a gate terminal; a protection circuit including a second p-channel FET having a drain terminal coupled to said first circuit node, a source terminal coupled to a first point of potential, and a gate terminal; a Hall plate having an input terminal coupled to said second circuit node, an output terminal coupled to a second point of reference potential, and first and second voltage taps, said Hall plate operative to sense a magnetic field and provide a difference in potential between said first and second voltage taps as a function of the magnetic field; a bias source coupled to said gate terminal of said first p-channel FET to provide a third potential thereat as a function of the magnitude of said first potential; a regulator circuit for providing a control signal to the gate terminal of said second p-channel FET, said regulator circuit thereby regulating output current of said Hall plate; whereby said cascade circuit is operative to provide a difference in potential between said first and second nodes, thereby increasing the breakdown strength of said Hall-sensor circuit.
The breakdown strength of monolithic integrated circuits is determined essentially by space-charge regions in the semiconductor material. The present invention takes advantage of the recognition that large voltage differences between two nodes can be reduced in steps by means of a one- or multi-stage p-channel cascade circuit, with the voltage being divided by the individual cascade stages into partial voltages of approximately equal magnitude. The partial voltages themselves must, of course, be smaller than the permissible breakdown voltages of the individual cascade stages. The operating range of each cascade stage is determined by a fixed potential, to which the respective gate electrode is connected. According to the invention, the cascade stages are built with p-channel transistors whose respective well potentials are approximately equal to or slightly above the source potentials. The gate electrodes are connected to associated fixed potentials which are generated by a bias source and are controlled as a function of the magnitude of the supply voltage. The control is to cause the cascode stages to be already be fully active in the starting range of the supply voltage. To increase the breakdown strength at the full supply voltage, p-channel cascode stages are used in the p-channel current path and voltage-proof n-channel transistors in the less critical n-channel path. In addition, the use of space-charge-free polysilicon resistors for the signal path is possible in both directions.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention and further embodiments thereof will now be explained in more detail with references to the accompanying drawings, in which:
FIG. 1 is a block diagram of a simple embodiment of the invention;
FIG. 2 shows the voltage waveform for driving the cascode circuit of FIG. 1;
FIG. 3 is a schematic diagram of another embodiment of the invention;
FIG. 4 shows the voltage waveform for driving the multi-stage cascode circuit of FIG. 3;
FIG. 5 is a schematic sectional view of the regions of a monolithic integrated protective circuit;
FIGS. 6 and 7 show equivalent circuits of the protective circuit of FIG. 5 in the normal and reverse-polarity conditions;
FIG. 8 shows a simple embodiment for generating a fixed potential, and
FIG. 9 is a schematic diagram of an embodiment of the invention in conjunction with a Hall-sensor circuit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, the circuit 20 has a contact pad 4, to which a positive supply voltage VDD is applied. Contact pad 4 feeds a first subcircuit 3 and a bias source 2. On the side remote from the positive supply voltage, the first subcircuit 3 has a first node k1, which is connected to the positive input of a cascode circuit 1. The negative output of the cascode circuit 1 is coupled to a second node k2, which is also the positive input to a second subcircuit 5, whose negative output is connected to a source of negative supply voltage VSS, which is connected to ground potential M.
In the embodiment of FIG. 1, the cascode circuit 1 is formed by a single p-channel transistor t having a source terminal S and well terminal W which are connected to the first node k1, and having a drain terminal D coupled to the second node k2. The gate terminal G is at a fixed potential HV which is provided by the output o of the bias source 2. The bias source 2 is fed at node 17 either by the positive supply voltage VDD or by the potential of the first node k1, as indicated by the dotted line 33. For simplicity, the cascode circuit 1 will hereinafter also be referred to as a "cascode". A channel current "i" flows from subcircuit 3 to subcircuit 5 between nodes k1 and k2 via the cascode 1. Examples of suitable subcircuits 3 and 5 will be described in detail hereinbelow.
FIG. 2 shows the gradient of the fixed potential HV, which is obtained from the output o of the bias source 2 of FIG. 1. At a supply voltage of, e.g., VDD=24 V, the fixed potential HV assumes a value N of approximately 12 V. As the supply voltage VDD decreases, the fixed potential HV decreases proportionally down to a first limiting value K, which corresponds to the value K' on the VDD axis. From there it decreases linearly until it reaches the ground reference level M at a second limiting value F.
In the starting range of the supply voltage VDD, i.e., in the range between O V and the second limiting value F, it is necessary for the fixed potential HV to be at or below ground potential M as soon as possible so that the p-channel current path i will be fully active (i.e., above pinch-off) at low VDD voltage values if possible. The exact gradient of the fixed potential HV between the first and second limiting values F and K, and between K and the maximum potential N, must only be predetermined such that no voltage breakdown will occur in any of the circuits 1, 3 or 5 at any voltage value VDD. The supply voltage VDD is divided by means of the subcircuit 2 such that the fixed potential HV is one half of VDD, for VDD greater than either K or another predetermined value less than K. Thus, up to a supply voltage VDD of 24 V, no circuit state is possible in the arrangements of FIG. 1 in which the potential HV is greater than 12 V.
FIG. 3 shows schematically another embodiment of the invention which is very similar to the embodiment of FIG. 1. For convenience, like reference symbols are used to designate like components. The cascode circuit 1 has been replaced with a three-stage cascode circuit 15 which contains three p-channel transistors t1, t2, t3 coupled in series and acting as a cascode combination. The source terminal S1 of the first p-channel transistor t1 is connected to the first node k1, and the drain terminal D3 of the third p-channel transistor t3 to the second node k2. The first, second, and third gate terminals g1, g2, g3 are connected, respectively, to first, second, and third outputs o1, o2, o3 of the bias source 22, which provides first, second, and third fixed potentials V1, V2, V3 at the respective outputs. The three output bias source 22 thus replaces the single output bias source 2 of FIG. 1. The multi-stage cascode circuit 15 makes it possible to apply a supply voltage VDD of more than 24 V, with the potential difference being reduced by up to 12 V at each cascode stage. The respective fixed-potential gradients V1, V2, V3 are shown schematically in FIG. 4.
The first subcircuit 3 of the embodiment of FIG. 3 contains two p-channel FETS 25 and 27 configured as a current mirror whose output is coupled to the first node k1. The second subcircuit 5 contains a voltage-insensitive n-channel transistor t n having a drain terminal 28 connected to the second node k2, and a source terminal 29 coupled to receive the voltage VSS, and a gate terminal 32 that is clocked by a signal source 6. The second node k2 thus provides an output voltage Vk which corresponds either to approximately the VSS potential or to the positive supply voltage VDD, depending on the circuit state. That is, if t n is in a high impedance state, or "off", as controlled by the clock, the voltage Vk will float to a high value, approaching VDD. When t n is "on" Vk will approach the potential VSS.
A simplified sectional view of the voltage-proof n-channel transistor t n is shown beside the subcircuit 5. Into the p-type substrate 34 a lightly doped n-type well w has been formed in which a highly doped (n+) type region 36 is disposed approximately about its center. The highly doped (n+) type region 36 and the n-type well w form the drain region D of the n-channel transistor t n . The source S is formed by a highly doped (n+) type region 38 as usual, and the gate region with the terminal G extends between the source S and drain D. Since the highly doped portion 36 of the drain region is surrounded by the lightly doped n-type well w, a space-charge region, which keeps the maximum field strength in the semiconductor material low, can form in the n-type well. Otherwise breakdown would occur at the junction boundary between the p-type substrate 34 and the highly doped (n+) type region 36.
In FIG. 5, the first subcircuit 3 is designed as a protective circuit 23 which provides protection against reversal of the polarities of the positive and negative supply voltages VDD, VSS. The protective circuit additionally contains an overvoltage protection element 50. The operation of the polarity-reversal protection will be explained with the aid of the cross section of FIG. 5 through various semiconductor regions and with the aid of the two equivalent circuits of FIGS. 6 and 7. The essential portion of the protective circuit 23 consists of a p-channel transistor structure 45 with drain, gate, and source regions d, g, s. These regions have been formed into an n-type well 40. Contact to the n-type well 40 is made via a heavily doped (n+) type region 44. The peculiarity of this protective circuit lies in the fact that the well terminal Wo is connected via a resistor R to the source terminal So. Instead of employing an external resistor R, a specifically designed region in the n-type well 40 can be used. This is achieved, for example, by extending the (p+) type source region 46 as a resistance region R' which connects the source terminal So to the well terminal Wo. The protective circuit illustrated in FIG. 5 is the subject matter of co-pending U.S. patent application Ser. No. 08/318,150 filed on Oct. 5, 1994, which contains a detailed description of the protection circuit.
The normal operating state is defined as follows. The contact pad 4, to which the positive supply voltage VDD is applied, is connected by a low-impedance path to the source terminal So. The drain terminal Do feeds the first node k1, which serves as a further internal power supply terminal. The gate terminal Go is driven either by means of a switching signal or by means of a regulation signal. With the switching signal, the p-channel transistor structure to turned on, so that the potential VDD' at the first node k1 is nearly equal to the positive supply voltage VDD. With the regulation signal, the p-channel transistor structure to serves to regulate the current delivered at the first node k1. (Both applications are implemented in the embodiment of FIG. 9, as will be described). Since, through the resistor R or R', the n-type well 40 is also connected to the positive supply voltage VDD, reliable operation of the p-channel transistor structure 45 is ensured.
FIG. 6 shows the equivalent circuit of FIG. 5 during normal operation. The equivalent bipolar pnp transistor 48 is formed as follows: the source region 46 forms the emitter E, the n-type well 40 forms the base B, the substrate 42 forms the collector C, and the drain region 43 forms a lateral collector C'. If the source region 46 is extended to form the resistor R' the entire (p+) type region will, of course, form the emitter E. During normal operation, the equivalent transistor 48 is off, since base B and emitter E are short-circuited via the currentless resistor R or R'.
In the event of a polarity reversal, the pn diode formed by the substrate and the n-type well 40 is forward-biased. Now the resistor R or R' becomes active. The well current cannot flow directly via the contact pad 4 but must flow through the resistor R or R', which limits its value. The effects of this resistor R or R' will be explained with the aid of the equivalent circuit of FIG. 7, which includes the inversely operated equivalent pnp transistor 48. Through the polarity reversal, the association of electrodes between the p-channel transistor structure 45 and the equivalent pnp transistor structure 48 changes as follows: the substrate 42 forms an emitter E, which is to be regarded as the primary emitter; the lateral drain region 43 forms a lateral emitter E'; the n-type well 40 still forms the base B, and the source region 46, together with the (p+) type extension for the resistor R' if present, forms a single collector C. Compared with FIG. 6, the equivalent pnp transistor 48 is operated in an inverse mode. The collector current ic indicated in FIG. 7 is given approximately by the following transistor equation:
ic=Binv×ib,
where ib=base current, ir=current through the resistor R, and Binv=inverse DC current gain of the equivalent pnp transistor 48. The effect of the lateral emitter E' is negligible since the major part of the well current is caused by the forward-biased, large-area well-substrate diode. The above equation shows that the maximum polarity-reversal current is dependent both on the inverse current gain Binv and on the magnitude of the base current ib and, hence, on the value of the resistor R (or R'). The circuit geometry and the doping of the respective regions are chosen so that the inverse current gain is approximately less than or equal to unity. Currents which flow through other n-type wells of the overall circuit may be critical if a large number of well terminals Wi are also connected through the resistor R. These currents add up to form the resistor current ir but do not increase the base current ib of the equivalent pnp transistor 48.
If an overvoltage protection element 50 is provided in the protective circuit of FIG. 5 to afford protection from excessive supply voltages VDD, this element will also be connected to the well contact Wo. A suitable overvoltage protection element 50 may be, for example, a buried zener diode which is formed by introducing appropriate regions into the semiconductor surface and whose breakdown voltage is settable relatively precisely by the fabrication process. Another suitable overvoltage protection element 50 is a field-oxide transistor, whose switching threshold is adjustable within wide limits by the field-oxide thickness so that it will become conducting with excessive voltage, thereby providing a low-impedance path to ground. Such a transistor, if it is an n-channel transistor, must be connected as follows: the source and bulk terminals are connected to ground potential M, and the gate and drain terminals are connected via a low-impedance path to the well terminal Wo. In the case of a permissible supply voltage VDD of 24 V, for example, an overvoltage protection element 50 must be provided whose breakdown voltage lies between 27 V and 32 V. If a separate contact pad is present for the well contact Wo, an external overvoltage protection element may be provided.
FIG. 8 is a circuit diagram of a circuit 52 which can be used for the bias source 2 of FIG. 1. Terminals 17 and 19 and output o are then coupled to other circuit components as in FIG. 1. The fixed potential HV is to be obtained from the output o. The circuit 52 provides the potential HV approximately as the idealized gradient of FIG. 2. The bias source 52 has a terminal 17 coupled to the first node k1 and terminal 19 connected to negative supply voltage VSS, with the=first node k1 at the potential VDD', which is nearly equal to the positive supply voltage VDD. Clamping of the fixed potential HV to ground potential M in the starting range is accomplished by turning on a transistor t7 by means of a first current bank m1. The input of the latter is fed from a voltage divider t1 which is connected as a direct-current path between the first node k1 and the current-bank input and whose resisters are formed by two series-connected p-channel transistors t4, t5. The drain terminal 54 of the transistor t5 is the low end of the voltage divider t1 and feeds the interconnected drain-gate terminal of an n-channel transistor t6, which serves as the current-bank input. To ensure breakdown strength, the well terminals of the transistors t4 and t5 are connected to the respective source electrodes.
The first current bank m1 is formed from the n-channel transistors t6, t7, t8. The drain terminal 58 of the transistor t7 is connected via a fourth node k4 to a relatively high-impedance diode chain nD which, like the voltage divider t1, may consist of series-connected p-channel transistors, each acting as a diode. The respective width to length ratio of the gate regions of diode chain nD transistors, are higher than those of the transistors t4, t5, t6 of the voltage divider t1. The other end of the diode chain nD is connected to the first node k1. The current transfer ratio of the first current bank m1 is chosen so that in the starting range of VDD, approximately up to the second limiting value F, the transistor t7 can turn on the diode chain nD. The voltage at node k4 then approaches the VSS potential when VDD is below F volts.
The second output of the first current bank m1, formed by the transistor t8, is coupled via a fifth node k5 to the input of a second current bank m2. The input and output of the latter are formed by p-channel transistors t9 and t10, respectively. The drain terminal 60 of the transistor t10 is coupled, via a p-channel transistor t11 used in a cascode configuration, to a third node k3 and, acting as a pull-up element, pulls this third node k3 in the positive voltage direction. From the third node k3, which is coupled to the output transistor t12 of a band-gap circuit bg, a regulated auxiliary voltage, namely a band-gap output voltage vr of, e.g., 3.8 V, can be obtained. The cascode formed by the transistor t11 serves to increase the breakdown strength between the transistor t10 and the third node k3. The gate terminal 62 of transistor t11 receives the fixed potential HV. Since in the starting range the fixed potential HV is less than or equal to ground potential M, the p-channel transistor t11 is in the switch mode and is fully on during this time.
The pull-down element for the third node k3 is the above-mentioned transistor t12, a p-channel transistor in the embodiment of FIG. 8. The gate electrode 64 of this transistor is driven by an output of the band-gap circuit bg, whose supply-voltage and reference inputs are connected directly to the third node k3. An example of a suitable band-gap circuit bg is described in great detail in the above-mentioned German Patent Application P 42 42 989.7, the content of which is incorporated herein by reference. If less stringent requirements are placed on the regulated voltage vr, a simpler circuit will suffice to activate the pull-down element t12.
If the band-gap circuit bg is not yet active in the starting range of the positive supply voltage VDD, the pull-down element t12 is not yet active, either. The third node k3 is therefore at a potential vr slightly below the respective supply voltage VDD'. As VDD rises, so does the voltage vr. When vr reaches a value large enough for the band-gap circuit bg to enter the active state, the band-gap circuit bg then acts to limit the voltage vr, by means of the control action, to the above-mentioned exemplary value of 3.8 V. A further output 66 of the band-gap circuit bg drives the gate terminal 68 of an n-channel transistor t13, whose drain terminal 70 is coupled to the fifth node k5. By means of the transistor t13, the second current bank m2 is driven with an additional input current. This current will later replace the input current from the first current bank m1, which, after the starting phase of the reference voltage vr (which is also considered the band-gap regulated output voltage), will generally be switched off below the second limiting value F.
The approximately linear characteristic of the fixed potential HV between the second and first limiting values F, K (see FIG. 2) is implemented with an n-channel transistor t16 which is driven by a further output 72 of the band-gap circuit bg. Transistor t16 loads the node k4 in this range F, K with a constant current, to which the current of the source follower t15 is added when the limiting value K has been reached.
Upon activation of the band-gap circuit bg, whose regulated output voltage vr is also delivered to other subcircuits of the overall circuit (as will be seen in FIG. 9), a safe operating mode is reached in which the overall circuit can no longer latch up in an undefined mode even if the supply voltage VDD is still relatively low. When VDD is at its full supply voltage, for example, an undefined mode may result in destructions if the fixed potential HV for the cascode circuits has locked to a false value. The normal operating range is determined in FIG. 8 by a switch arrangement sw with an n-channel transistor t14 which is driven by the band-gap output voltage vr via a voltage divider 74 which determines a switching threshold. As soon as this voltage vr exceeds a predetermined value, transistor t14 turns on, thereby lowering the potential at node k6 to near the VSS potential, which disconnects the first current bank m1. As a rule, the switching threshold should be set so that transistor t14 switches for a VDD valve below the limiting value F, provided the band-gap circuit bg is already active.
In FIG. 8, the switch arrangement sw is connected to the band-gap output voltage vr to simplify the illustration. It would be more suitable, however, if the switch activation were initiated by a current path of the band-gap circuit bg, where this current path turns on last, because this would ensure that all important subcircuits are already active. A circuit arrangement which accomplishes this is described, for example, in the above-mentioned German Patent Application P 42 42 989.7 in connection with a starting circuit.
Through the disconnection of the first current bank m1, the output transistors t7, t8 of the latter are cut off. As a result, the diode chain nD pulls the potential of the fourth node k4 from ground potential M to a higher potential. The input current for the second current bank m2, as mentioned above, is supplied by the transistor t13, which is controlled by the band-gap circuit bg. Since the voltage at the fourth node k4 represents the fixed potential HV, which should normally be equal to half the supply voltage, VDD/2, the fourth node k4 must have a low source impedance. This is accomplished by means of the source follower consisting of the p-channel transistor t15 whose gate terminal 75 is connected to the center tap 76 of the voltage divider t1. The fixed potential HV is thus stabilized and can fix the gate potentials of the various cascode circuits, including, for example, that of transistor t11. The fact that the fixed potential HV is tied to the voltage-divider tap causes the proportional dependence of VDD from the limiting valve K. The transition region between the second limiting valve F and first limiting valve K is dependent on the switching threshold and the current-transfer behavior of the stages involved. If the bias source 2 has to generate several fixed potentials V1, V2, V3 as in FIG. 3, the voltage divider t1 will have corresponding taps which are connected to one source follower each. Each fixed-potential-generating facility contains its own, relatively high-impedance pull-up arrangement.
FIG. 9 shows an embodiment of the invention in conjunction with a Hall-sensor circuit 95 which can be connected directly to an unregulated supply voltage of 24 V. The Hall-sensor circuit 95 is protected against polarity reversals of the positive and negative supply voltages VDD, VSS. In addition, circuit 95 includes two overvoltage protection elements 82, 84, one at the respective well terminal Wo of each of the two p-channel transistor structures 90, 91. The Hall-sensor circuit 95 is a device having three terminals, with which the contact pads 4, 8, and 9 for the positive supply voltage VDD, the negative supply voltage VSS, and the output signal Ot are associated. Like reference numerals are used for convenience to designate the same components or circuit inputs as previously described.
The contact pad 4 has a regulated protective circuit 31 and switched protective circuit 35 connected thereto via a low-impedance path. The regulated protective circuit 31 generates an operating current ih for a monolithic integrated Hall plate 51, whose low end terminal 94 is connected to VSS. The Hall plate 51 senses a magnetic field and provides a difference in potential Vh between the taps 98, 99 as a function of the magnetic field sensed. The output of the regulated circuit 31 is at a first node k11, and the input for the operating current ih of the Hall plate is at a second node k21. An approximately 20-V difference voltage between the first and second nodes k11, k21 ocurrs across a cascode circuit 11 consisting of a p-channel transistor t whose gate terminal is connected to a fixed potential HV of approximately 12 V delivered by a bias source 2 at the output o. The bias source 2 may be implemented with a circuit as shown in FIG. 8. The regulated operating current ih for the Hall plate 51 is generated by driving the gate terminal Go of the regulated protective circuit 31 with a regulation signal si from a regulator circuit 97.
The regulated protective circuit 31 may be equivalent to the polarity-reversal protection structure of FIG. 5. That is, the transistor 90 structure may be equivalent to that of transistor 45, with the resistor R connected to the well terminal Wo, and so on. The switched protective circuit 35, which is also connected via a low-impedance path to the contact pad 4, contains the same elements as the regulated protective circuit 31, with transistor 91 being equivalent to transistor 90. From its output node k15 a positive supply voltage VDD' can be obtained which is only negligibly below the potential VDD of the contact pad 4. This follows from the fact that the gate terminal Go of transistor 91 is connected to the fixed potential HV, so that transistor 91 is turned fully on. The node k15 therefore serves as an internal terminal for the positive supply voltage VDD' of the CMOS circuit. A part of this circuit is implemented with an analog and/or signal-processing circuit 55, whose inputs are fed with the Hall-voltage difference Vh. Vh can be evaluated in the circuit 55 in analog, digital, or mixed form. In the example of FIG. 9, only a single output terminal 9 is present for the output signal Ot. In the simplest case, the Hall-sensor circuit 95 operates as a switch and provides a switching signal at the output terminal 9 when the magnetic field measured by the Hall plate 51 exceeds or falls below a predetermined value. For this application, only a low-cost three-lead package is necessary, which, however, involves the risk of a hook-up error in which VDD and VSS could be erroneously interchanged. Because of the two protective circuits 31 and 35, however, such a hook-up error has no negative consequences for the operation of the device.
Power is supplied to the circuit 55 via the single-stage cascade 15 inserted as a p-channel current path between the first and second nodes k15 and k25. The associated p-channel transistor t has its gate terminal tied to the fixed potential HV. Similarly, the regulator circuit 97 and any control circuit 101 that may be present are connected to the node k15 via cascode circuits 17 and 110, respectively. The regulator circuit 97 and the evaluating circuit 55 may be connected to the output supplying the regulated band-gap output voltage vr of the bias source 2 previously described with reference to FIG. 8. In the regulator circuit 97, the band-gap output voltage vr serves as a reference voltage to regulate the operating current ih by means of a replica (not shown) of the Hall plate 51 within the regulator circuit 97. In the evaluating circuit 55, the band-gap output voltage vr serves as a voltage reference for the Hall difference voltage Vh to control, for example, the switching function at the output terminal 9. The Hall plate 51 is indicated in FIG. 9 only schematically: Hall plate 51 may be a multiple-Hall-plate arrangement whose respective operating currents and voltage taps are cyclically switched by the control circuit 101, see, for example, European Patent Application EP-A-O 548 391 to S. Mehrgardt et al. and assigned to the assignee herein, the content of which is incorporated herein by reference.
Between the node k15 and each of the cascode circuits 110, 17, and 15, a p-channel transistor tr is inserted whose gate is controlled by a respective output of the regulator circuit 97. With this arrangement, only one protective circuit 35 as shown is needed to protect against reverse polarity operation. The individual regulation of the currents can then be accomplished in a simple manner by the ordinary p-channel transistors tr, which need no longer be protected against the destructive reverse mode. It should be pointed out that the regulated protective circuit 31 could also be replaced by a p-channel transistor tr connected to the node k15, but this would not be advisable because of the large operating currents ih of the Hall plate 51.
It should be understood that the embodiments described herein are merely exemplary and that a person skilled in the art may make many variations and modifications to the described embodiments utilizing functionally equivalent components to those described. All such variations and modifications are intended to be included within the spirit and scope of this invention as defined by the appended claims. | In a CMOS circuit having at least a first subcircuit coupled between a first point of potential and a first circuit node, and having a second subcircuit coupled between a second circuit node and a second point of potential, said first and second circuit nodes being coupled together, the improvement in combination therewith, comprising: first circuit means coupled to the first point of potential for converting the first potential to a third potential as a function of the magnitude of said first potential, said third potential being of a value inbetween the first and second potentials; a FET having source, drain, gate and well terminals, said source terminal being coupled to said well terminal and to said first circuit node, said third potential being applied to said gate terminal, said drain terminal being coupled to said second circuit node; wherein said FET, in conjunction with said first circuit means, operates to selectively provide a difference in potential between said first and second circuit nodes, thereby preventing voltage breakdown within said subcircuits. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/986,191, filed on Nov. 7, 2007, the contents of which are herein incorporated by reference in their entirety for all purposes.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] NOT APPLICABLE
BACKGROUND OF THE INVENTION
[0003] Homogeneous assay formats avoid the need for separation of an added detectably labeled specific binding partner is used. This type of methodology relies on devising a detection principle that is either turned on or turned off as a result of the binding reaction. In contrast, heterogeneous assays formats rely on physical separation of bound and free detectably labeled specific binding partners before quantitation.
[0004] Homogeneous enzyme immunoassays generally exploit the antibody:antigen binding reaction to either activate or inhibit a label enzyme and may involve various methods of quenching fluorescence through antibodies or other fluorescent quenchers. Despite the considerable efforts made in devising homogeneous, or non-separation, assay formats, they still do not experience widespread commercial adoption. Heterogeneous assays are viewed as simpler to develop and mass-produce, even though they are operationally more complex. In particular, the field of high volume clinical immunodiagnostics and the smaller field of clinical nucleic acid diagnostics are dominated by heterogeneous assay formats. Within this arena, test formats would be beneficial to the field that could simplify protocols, reduce complexity and improve compatibility with automation by removing unnecessary steps. The present invention addresses these and other needs in the art.
BRIEF SUMMARY OF THE INVENTION
[0005] The present invention provides simple and efficient assay methods of detecting analytes. The assays presented herein may be performed for applications such as diagnostics and high through-put screening procedures.
[0006] In one aspect, a novel method of detecting an analyte in a sample is provided. The method includes contacting the analyte with a solid support conjugate and a first analyte binder conjugate. The first analyte binder conjugate is a peroxidase enzyme conjugated to a first analyte binder. The solid support conjugate is a solid support that is conjugated to a second analyte binder, a peroxide generating enzyme, and a chemiluminescent compound. The analyte is allowed to bind to the first analyte binder and the second analyte binder thereby forming a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal.
[0007] In another aspect, a method of detecting an analyte in a sample is provided. The method includes contacting the analyte with a solid support conjugate and a first analyte binder conjugate. The first analyte binder conjugate is a peroxidase enzyme conjugated to a first analyte binder and the first analyte binder is being bound to a competition analyte. The solid support conjugate is a solid support conjugated to a second analyte binder, a peroxide generating enzyme, and a chemiluminescent compound. The analyte and the first analyte binder conjugate are allowed to competitively bind to the second analyte binder. The binding of the first analyte binder conjugate to the second analyte binder forms a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal.
[0008] In another aspect, a solid support conjugate is provided. The solid support conjugate includes a solid support conjugated to a chemiluminescent compound, a hydrogen peroxide generating enzyme, and an analyte binder.
[0009] In another aspect, a kit for detecting an analyte in a sample is provided. The kit includes a first analyte binder conjugate that is conjugated to a peroxidase enzyme, and a solid support conjugate that is conjugated to a second analyte binder, a peroxide generating enzyme, and a chemiluminescent compound.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic representation of a chemiluminescent detection method including a solid support conjugate and a first analyte binder conjugate, a peroxide generating enzyme, a peroxide generating enzyme substrate, and a chemiluminescent compound.
DETAILED DESCRIPTION OF THE INVENTION
I. Definitions
[0011] Generally, a “sample” represents a mixture containing or suspected of containing an analyte to be measured in an assay. Samples which can be typically used in the methods of the invention include bodily fluids such as blood, which can be anti-coagulated blood as is commonly found in collected blood specimens, plasma, urine, semen, saliva, cell cultures, tissue extracts and the like. Other types of samples include solvents, seawater, industrial water samples, food samples and environmental samples such as soil or water, plant materials, eukaryotes, bacteria, plasmids, viruses, fungi, and cells originated, from prokaryotes.
[0012] An “analyte” is a substance in a sample to be detected in an assay. The analyte can be a protein, a peptide, an antibody, or a hapten to which an antibody that binds it can be made. The analyte can be a nucleotide or oligonucleotide which is bound by a complementary nucleic acid or oligonucleotide. Other types of analytes include, drugs such as steroids, hormones, proteins, glycoproteins, mucoproteins, nucleoproteins, phosphoproteins, drugs of abuse, vitamins, antibacterials, antifungals, antivirals, purines, antineoplastic agents, amphetamines, azepine compounds, nucleotides, and prostaglandins, as well as metabolites of any of these drugs, pesticides and metabolites of pesticides, and receptors. Analytes also include cells, viruses, bacteria and fungi.
[0013] The term “specific binding” refers to binding between two molecules such as a ligand and a receptor and is characterized by the ability of a molecule (ligand) to associate with another specific molecule (receptor) in the presence of many other diverse molecules. Specific binding of a ligand to a receptor is also evidenced by reduced binding of a detectably labeled ligand to the receptor in the presence of excess of unlabeled ligand (i.e. a binding competition assay).
[0014] The term “antibody” (Ab) refers to a polypeptide with a framework region from an immunoglobulin gene or fragments thereof that specifically binds and recognizes an antigen. The recognized immunoglobulin genes include the kappa, lambda, alpha, gamma, delta, epsilon, and mu constant region genes, as well as the myriad immunoglobulin variable region genes. Immunoglobulin light chains are classified as either kappa or lambda, whereas immunoglobulin heavy chains are classified as gamma, mu, alpha, delta, or epsilon. The immunoglobulin heavy chains define the immunoglobulin classes (isotypes), IgG, IgM, IgA, IgD and IgE, respectively. Typically, the antigen-binding region of an antibody will be most critical in specificity and affinity of binding. Antibodies can be polyclonal or monoclonal, derived from serum, a hybridoma or recombinantly cloned, and can also be chimeric, primatized, or humanized.
[0015] An example of an immunoglobulin (antibody) structural unit includes a tetramer. Each tetramer is composed of two identical pairs of polypeptide chains, each pair having one “light” (about 25 kD) and one “heavy” chain (about 50-70 kD). Disulfide bonds connect the heavy chain and the light chain of each individual pair. Further, the two heavy chains of each binding pair are connected through a disulfide bond in the hinge region. Each heavy and light chain has two regions, a constant region and a variable region. The constant region of the heavy chain is identical in all antibodies of the same isotype, but differs in antibodies of different isotypes. The variable region located at the N-terminus of the heavy and the light chain includes about 100 to 110 or more amino acids and is primarily responsible for antigen recognition. The terms variable light chain (V L ) and variable heavy chain (V H ) refer to these light and heavy chains, respectively.
[0016] Antibodies exist, for example as intact immunoglobulins or as a number of well-characterized fragments produced by digestion with various peptidases. Thus, for example, pepsin digests an antibody below the disulfide linkages in the hinge region to produce F(ab)′ 2 , a dimer of Fab, which itself is a light chain joined to V H —C H 1 by a disulfide bond. The F(ab)′ 2 may be reduced under mild conditions to break the disulfide linkage in the hinge region, thereby converting the F(ab)′ 2 dimer into a Fab monomer. The Fab monomer is essentially Fab with part of the hinge region (see Fundamental Immunology (Paul ed., 3d ed. 1993). While various antibody fragments are defined in terms of the digestion of an intact antibody, one of skill will appreciate that such fragments may be synthesized de novo either chemically or by using recombinant DNA methodology. Thus, the term antibody, as used herein, also includes antibody fragments either produced by the modification of whole antibodies, or those synthesized de novo using recombinant DNA methodologies (e.g., single chain Fv) or those identified using phage display libraries (see, e.g., McCafferty et al., Nature 348:552-554 (1990)).
[0017] A “chemiluminescent compound” as used herein, refers to a monovalent chemiluminescent compound conjugated to a solid support, comprising a chemiluminescent moiety and a linking moiety. The terms “chemiluminescent group” and “chemiluminescent moiety” are used interchangeably as are the terms “linking moiety” and “linking group.” The chemiluminescent moiety may undergo a reaction with an activator resulting in the conversion of the chemiluminescent moiety into a higher or excited state of energy. Without being bound by any particular mechanistic theory, the excited state may directly emit light upon relaxation or may transfer excitation energy to an emissive energy acceptor, thereby returning to the ground state. After being excited the emissive energy acceptor may emit light. A class of compounds which by incorporation of a linking moiety could serve as a chemiluminescent compound include, but is not limited to, cyclic diacylhydrazides such as luminol and structurally related cyclic hydrazides including isoluminol, aminobutylethylisoluminol (ABET), aminohexylethylisoluminol (AHEI), 7-dimethylaminonaphthalene-1,2-dicarboxylic acid hydrazide, ring-substituted aminophthalhydrazides, anthracene-2,3-dicarboxylic acid hydrazides, phenanthrene-1,2-dicarboxylic acid hydrazides, pyrenedicarboxylic acid hydrazides, 5-hydroxyphthal-hydrazide, 6-hydroxyphthalhydrazide, as well as other phthalazinedione analogs disclosed in U.S. Pat. No. 5,420,275 to Masuya et al. and in U.S. Pat. No. 5,324,835 to Yamaguchi. Other examples for compounds that may serve as a chemiluminescent moiety of the chemiluminescent compound used in the present invention are xanthene dyes such as fluorescein, eosin, rhodamine dyes, or rhodol dyes, aromatic amines and heterocyclic amines, acridan esters, thioesters and sulfonamides, and acridan ketenedithioacetal compounds that are known in the art to produce chemiluminescence by reaction with peroxide and peroxidase.
[0018] The term “alkyl,” by itself or as part of another substituent, means, unless otherwise stated, a straight or branched chain, or cyclic hydrocarbon radical, or combination thereof, which may be fully saturated, mono- or polyunsaturated and can include di- and multivalent radicals, having the number of carbon atoms designated (i.e. C 1 -C 10 means one to ten carbons). Examples of saturated hydrocarbon radicals include, but are not limited to, groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, sec-butyl, cyclohexyl, (cyclohexyl)methyl, cyclopropylmethyl, homologs and isomers of, for example, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like. An unsaturated alkyl group is one having one or more double bonds or triple bonds. Examples of unsaturated alkyl groups include, but are not limited to, vinyl, 2-propenyl, crotyl, 2-isopentenyl, 2-(butadienyl), 2,4-pentadienyl, 3-(1,4-pentadienyl), ethynyl, 1- and 3-propynyl, 3-butynyl, and the higher homologs and isomers. The term “alkyl,” unless otherwise noted, is also meant to include those derivatives of alkyl defined in more detail below, such as “heteroalkyl.” Alkyl groups that are limited to hydrocarbon groups are termed “homoalkyl”. An alkoxy is an alkyl attached to the remainder of the molecule via an oxygen linker (—O—).
[0019] The term “alkylene” by itself or as part of another substituent means a divalent radical derived from an alkyl, as exemplified, but not limited, by —CH 2 CH 2 CH 2 CH 2 —, and further includes those groups described below as “heteroalkylene.” Typically, an alkyl (or alkylene) group will have from 1 to 24 carbon atoms, with those groups having 10 or fewer carbon atoms being preferred in the present invention. A “lower alkyl” or “lower alkylene” is a shorter chain alkyl or alkylene group, generally having eight or fewer carbon atoms.
[0020] The term “heteroalkyl,” by itself or in combination with another term, means, unless otherwise stated, a stable straight or branched chain, or cyclic hydrocarbon radical, or combinations thereof, consisting of at least one carbon atoms and at least one heteroatom selected from the group consisting of O, N, P, Si and S, and wherein the nitrogen and sulfur atoms may optionally be oxidized and the nitrogen heteroatom may optionally be quaternized. The heteroatom(s) O, N, P and S and Si may be placed at any interior position of the heteroalkyl group or at the position at which the alkyl group is attached to the remainder of the molecule. Examples include, but are not limited to, —CH 2 —CH 2 —O—CH 3 , —CH 2 —CH 2 —NH—CH 3 , —CH 2 —CH 2 —N(CH 3 )—CH 3 , —CH 2 —S—CH 2 —CH 3 , —CH 2 —CH 2 , —S(O)—CH 3 , —CH 2 —CH 2 —S(O) 2 —CH 3 , —CH═CH—O—CH 3 , —Si(CH 3 ) 3 , —CH 2 —CH═N—OCH 3 , —CH═CH—N(CH 3 )—CH 3 , O—CH 3 , —O—CH 2 —CH 3 , and —CN. Up to two heteroatoms may be consecutive, such as, for example, —CH 2 —NH—OCH 3 . Similarly, the term “heteroalkylene” by itself or as part of another substituent means a divalent radical derived from heteroalkyl, as exemplified, but not limited by, —CH 2 —CH 2 —S—CH 2 —CH 2 — and —CH 2 —S—CH 2 —CH 2 —NH—CH 2 —. For heteroalkylene groups, heteroatoms can also occupy either or both of the chain termini (e.g., alkyleneoxy, alkylenedioxy, alkyleneamino, alkylenediamino, and the like). Still further, for alkylene and heteroalkylene linking groups, no orientation of the linking group is implied by the direction in which the formula of the linking group is written. For example, the formula —C(O) 2 R′— represents both —C(O) 2 R′— and —R′C(O) 2 —. As described above, heteroalkyl groups, as used herein, include those groups that are attached to the remainder of the molecule through a heteroatom, such as —C(O)R′, —C(O)NR′, —NR′R″, —OR′, —SR′, and/or —SO 2 R′. Where “heteroalkyl” is recited, followed by recitations of specific heteroalkyl groups, such as —NR′R″ or the like, it will be understood that the terms heteroalkyl and —NR′R″ are not redundant or mutually exclusive. Rather, the specific heteroalkyl groups are recited to add clarity. Thus, the term “heteroalkyl” should not be interpreted herein as excluding specific heteroalkyl groups, such as —NR′R″ or the like.
[0021] The terms “cycloalkyl” and “heterocycloalkyl” (also referred to herein as a “heterocyclic”), by themselves or in combination with other terms, represent, unless otherwise stated, cyclic versions of “alkyl” and “heteroalkyl”, respectively. Additionally, for heterocycloalkyl, a heteroatom can occupy the position at which the heterocycle is attached to the remainder of the molecule. Examples of cycloalkyl include, but are not limited to, cyclopentyl, cyclohexyl, 1-cyclohexenyl, 3-cyclohexenyl, cycloheptyl, and the like. Examples of heterocycloalkyl include, but are not limited to, 1-(1,2,5,6-tetrahydropyridyl), 1-piperidinyl, 2-piperidinyl, 3-piperidinyl, 4-morpholinyl, 3-morpholinyl, tetrahydrofuran-2-yl, tetrahydrofuran-3-yl, tetrahydrothien-2-yl, tetrahydrothien-3-yl, 1-piperazinyl, 2-piperazinyl, and the like. The terms “cycloalkylene” and “heterocycloalkylene” refer to the divalent derivatives of cycloalkyl and heterocycloalkyl, respectively.
[0022] The terms “halo” or “halogen,” by themselves or as part of another substituent, mean, unless otherwise stated, a fluorine, chlorine, bromine, or iodine atom. Additionally, terms such as “haloalkyl,” are meant to include monohaloalkyl and polyhaloalkyl. For example, the term “halo(C 1 -C 4 )alkyl” is mean to include, but not be limited to, trifluoromethyl, 2,2,2-trifluoroethyl, 4-chlorobutyl, 3-bromopropyl, and the like.
[0023] The term “acyl” means —C(O)R where R is a substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl.
[0024] The term “aryl” means, unless otherwise stated, a polyunsaturated, aromatic, substituent that can be a single ring or multiple rings (preferably from 1 to 3 rings), which are fused together or linked covalently. The term “heteroaryl” refers to aryl groups (or rings) that contain from one to four heteroatoms selected from N, O, and S, wherein the nitrogen and sulfur atoms are optionally oxidized, and the nitrogen atom(s) are optionally quaternized. A heteroaryl group can be attached to the remainder of the molecule through a heteroatom. Non-limiting examples of aryl and heteroaryl groups include phenyl, 1-naphthyl, 2-naphthyl, 4-biphenyl, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 3-pyrazolyl, 2-imidazolyl, 4-imidazolyl, pyrazinyl, 2-oxazolyl, 4-oxazolyl, 2-phenyl-4-oxazolyl, 5-oxazolyl, 3-isoxazolyl, 4-isoxazolyl, 5-isoxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 2-furyl, 3-furyl, 2-thienyl, 3-thienyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidyl, 4-pyrimidyl, 5-benzothiazolyl, purinyl, 2-benzimidazolyl, 5-indolyl, 1-isoquinolyl, 5-isoquinolyl, 2-quinoxalinyl, 5-quinoxalinyl, 3-quinolyl, and 6-quinolyl. Substituents for each of the above noted aryl and heteroaryl ring systems are selected from the group of acceptable substituents described below. The terms “arylene” and “heteroarylene” refer to the divalent radicals of aryl and heteroaryl, respectively.
[0025] For brevity, the term “aryl” when used in combination with other terms (e.g., aryloxy, arylthioxy, arylalkyl) includes both aryl and heteroaryl rings as defined above. Thus, the term “arylalkyl” is meant to include those radicals in which an aryl group is attached to an alkyl group (e.g., benzyl, phenethyl, pyridylmethyl and the like) including those alkyl groups in which a carbon atom (e.g., a methylene group) has been replaced by, for example, an oxygen atom (e.g., phenoxymethyl, 2-pyridyloxymethyl, 3-(1-naphthyloxy)propyl, and the like).
[0026] The term “oxo” as used herein means an oxygen that is double bonded to a carbon atom.
[0027] The term “alkylsulfonyl” as used herein means a moiety having the formula —S(O 2 )—R′, where R′ is an alkyl group as defined above. R′ may have a specified number of carbons (e.g. “C 1 -C 4 alkylsulfonyl”).
[0028] Each of the above terms (e.g., “alkyl,” “heteroalkyl,” “aryl” and “heteroaryl”) are meant to include both substituted and unsubstituted forms of the indicated radical. Preferred substituents for each type of radical are provided below.
[0029] Substituents for the alkyl and heteroalkyl radicals (including those groups often referred to as alkylene, alkenyl, heteroalkylene, heteroalkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl) are generically referred to as “alkyl group substituents,” and they can be one or more of a variety of groups selected from, but not limited to: —OR′, ═O, ═NR′, ═N—OR′, —NR′R″, —SR′, -halogen, —SiR′R″R′″, —OC(O)R′, —C(O)R′, —CO 2 R′, —CONR′R″, —OC(O)NR′R″, —NR″C(O)R′, —NR″—C(O)NR″R′″, —NR″C(O) 2 R′, —NR—C(NR′R″R′″)═NR″″, —NR—C(NR′R″)═NR′″, —S(O)R′, —S(O) 2 R′, —S(O) 2 NR′R″, —NRSO 2 R′, —CN, — + NR 3 , — + PR 3 , —B(OH) 2 , and —NO 2 in a number ranging from zero to (2 m′+1), where m′ is the total number of carbon atoms in such radical. R′, R″, R′″ and R″″ each preferably independently refer to hydrogen, substituted or unsubstituted heteroalkyl, substituted or unsubstituted aryl, e.g., aryl substituted with 1-3 halogens, substituted or unsubstituted alkyl, alkoxy or thioalkoxy groups, or arylalkyl groups. When a compound of the invention includes more than one R group, for example, each of the R groups is independently selected as are each R′, R″, R′″ and R″″ groups when more than one of these groups is present. When R′ and R″ are attached to the same nitrogen atom, they can be combined with the nitrogen atom to form a 5-, 6-, or 7-membered ring. For example, —NR′R″ is meant to include, but not be limited to, 1-pyrrolidinyl and 4-morpholinyl. From the above discussion of substituents, one of skill in the art will understand that the term “alkyl” is meant to include groups including carbon atoms bound to groups other than hydrogen groups, such as haloalkyl (e.g., —CF 3 and —CH 2 CF 3 ) and acyl (e.g., —C(O)CH 3 , —C(O)CF 3 , —C(O)CH 2 OCH 3 , and the like).
[0030] Similar to the substituents described for the alkyl radical, substituents for the aryl and heteroaryl groups are generically referred to as “aryl group substituents.” The substituents are selected from, for example: halogen, —OR′, ═O, ═NR′, ═N—OR′, —NR′R″, —SR′, -halogen, —SiR′R″R′″, —OC(O)R′, —C(O)R′, —CO 2 R′, —CONR′R″, —OC(O)NR′R″, —NR″C(O)R′, —NR′—C(O)NR″R′″, —NR″C(O) 2 R′, —NR—C(NR′R″R′″)═NR″″, —NR—C(NR′R″)═NR′″, —S(O)R′, —S(O) 2 R′, —S(O) 2 NR′R″, —NRSO 2 R′, —CN, — + NR 3 , — + PR 3 , —B(OH) 2 , and —NO 2 , —R′, —N 3 , —CH(Ph) 2 , fluoro(C 1 -C 4 )alkoxy, and fluoro(C 1 -C 4 )alkyl, in a number ranging from zero to the total number of open valences on the aromatic ring system; and where R′, R″, R′″ and R″″ are preferably independently selected from hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted aryl and substituted or unsubstituted heteroaryl. When a compound of the invention includes more than one R group, for example, each of the R groups is independently selected as are each R′, R″, R′″ and R″″ groups when more than one of these groups is present.
[0031] Two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula -T-C(O)—(CRR′) q —U—, wherein T and U are independently —NR—, —O—, —CRR′— or a single bond, and q is an integer of from 0 to 3. Alternatively, two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula -A-(CH 2 ) r —B—, wherein A and B are independently —CRR′—, —O—, —NR—, —S—, —S(O)—, —S(O) 2 —, —S(O) 2 NR′— or a single bond, and r is an integer of from 1 to 4. One of the single bonds of the new ring so formed may optionally be replaced with a double bond. Alternatively, two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula —(CRR′) s —X—(CR″R′″) d —, where s and d are independently integers of from 0 to 3, and X is —O—, —NR′—, —S—, —S(O)—, —S(O) 2 —, or —S(O) 2 NR′—. The substituents R, R′, R″ and R′″ are preferably independently selected from hydrogen or substituted or unsubstituted (C 1 -C 6 )alkyl.
[0032] As used herein, the term “heteroatom” is meant to include oxygen (O), nitrogen (N), sulfur (S), silicon (Si) and phosphorus (P).
[0033] A “substituent group,” as used herein, means a group selected from the following moieties:
[0034] (A) —OH, —NH 2 , —SH, —CN, —CF 3 , —NO 2 , oxo, halogen, unsubstituted alkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, unsubstituted heteroaryl, and
[0035] (B) alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, substituted with at least one substituent selected from:
[0036] (i) oxo, —OH, —NH 2 , —SH, —CN, —CF 3 , — + NR 3 , — + PR 3 , —B(OH) 2 , —NO 2 , halogen, unsubstituted alkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, unsubstituted heteroaryl, and
[0037] (ii) alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, substituted with at least one substituent selected from:
[0038] (a) oxo, —OH, —NH 2 , —SH, —CN, —CF 3 , —NO 2 , halogen, unsubstituted alkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, unsubstituted heteroaryl, and
[0039] (b) alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, substituted with at least one substituent selected from oxo, —OH, —NH 2 , —SH, —CN, —CF 3 , —NO 2 , halogen, unsubstituted alkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, and unsubstituted heteroaryl.
[0040] As used herein, “amino acid” refers to a group of water-soluble compounds that possess both a carboxyl and an amino group attached to the same carbon atom. Amino acids can be represented by the general formula NH 2 —CHR—COOH where R may be hydrogen or an organic group, which may be nonpolar, basic acidic, or polar. As used herein, “amino acid” refers to both the amino acid radical and the non-radical free amino acid.
[0041] The term “hydroxy” is used herein to refer to the group —OH.
[0042] The term “amino” is used to describe primary amines, —NRR′, wherein R and R′ are independently H, alkyl, aryl or substituted analogues thereof “Amino” encompasses “alkylamino” denoting secondary and tertiary amines and “acylamino” describing the group RC(O)NR′.
[0043] The term “alkoxy” is used herein to refer to the —OR group, where R is alkyl, aryl, or substituted analogues thereof. Suitable alkoxy radicals include, for example, methoxy, ethoxy, phenoxy, substituted phenoxy, benzyloxy, phenethyloxy, t-butoxy, etc.
[0044] The term “acyloxy” is used herein to describe an organic radical derived from an organic acid by the removal of the acidic hydrogen. Simple acyloxy groups include, for example, acetoxy, and higher homologues derived from carboxylic acids such as ethanoic, propanoic, butanoic, etc. The acyloxy moiety may be oriented as either a forward or reverse ester (i.e. RC(O)OR′ or R′OC(O)R).
[0045] A “ring,” as used herein, refers to a substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, and/or substituted or unsubstituted heteroaryl.
[0046] As used herein, “nucleic acid” means either DNA, RNA, single-stranded, double-stranded, or more highly aggregated hybridization motifs, and any chemical modifications thereof. Modifications include, but are not limited to, those which provide other chemical groups that incorporate additional charge, polarizability, hydrogen bonding, electrostatic interaction, and functionality to the nucleic acid ligand bases or to the nucleic acid ligand as a whole. Such modifications include, but are not limited to, peptide nucleic acids, phosphodiester group modifications (e.g., phosphorothioates, methylphosphonates), 2′-position sugar modifications, 5-position pyrimidine modifications, 8-position purine modifications, modifications at exocyclic amines, substitution of 4-thiouridine, substitution of 5-bromo or 5-iodo-uracil; backbone modifications, methylations, unusual base-pairing combinations such as the isobases isocytidine and isoguanidine and the like. Modifications can also include 3′ and 5′ modifications such as capping.
[0047] A “nucleobase” is a nucleoside or nucleotide. A “nucleoside” is a deoxyribose or ribose sugar, or derivative thereof, containing a nitrogenous base linked to the C1′ of the sugar residue. A “nucleotide” is the C5′ phosphate ester derivative of a nucleoside. The terms “nucleoside and “nucleotide” include those compounds having non-natural substituents at the C1′, C2′, C3′, C5′, and/or nitrogenous base (e.g., C2′ alkyl, alkoxy, and halogen substituents).
[0048] “Polypeptide” refers to a polymer in which the monomers are amino acids and are joined together through amide bonds, alternatively referred to as a peptide. When the amino acids are α-amino acids, either the l-optical isomer or the d-optical isomer can be used. Additionally, unnatural amino acids, for example, β-alanine, phenylglycine and homoarginine are also included. Commonly encountered amino acids that are not gene-encoded may also be used in the present invention. All of the amino acids used in the present invention may be either the d- or 1-isomer. The 1-isomers are generally preferred. In addition, other peptidomimetics are also useful in the present invention. For a general review, see, Spatola, A. F., in Chemistry and Biochemistry of Amino Acids, Peptides and Proteins, B. Weinstein, eds., Marcel Dekker, New York, p. 267 (1983).
II. Methods of Analyte Detection
[0049] In one aspect, a novel method of detecting an analyte in a sample is provided. The method includes contacting the analyte with a solid support conjugate and a first analyte binder conjugate. The first analyte binder conjugate is a peroxidase enzyme conjugated to a first analyte binder. The solid support conjugate is a solid support that is conjugated to a second analyte binder, a peroxide generating enzyme, and a chemiluminescent compound. The analyte is allowed to bind to the first analyte binder and the second analyte binder thereby forming a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal. In some embodiments, the detectable solid support bound analyte complex is also contacted with a peroxidase enhancer compound.
[0050] Analytes that are detected using the methods provided herein include, cardiac markers and cardiac drugs such as Troponin I, CK-MB, digoxin, myoglobin and BNP. In other embodiments, the analyte is a drug and analyte related to reproductive function including AFP, DHEA-S, estradiol, FSH, LK, Inhibin A, PAPP-A, PIGF, sVEGF R1, progesterone, prolactin, SHBG, testosterone, βHCG, and unconjugated estriol. Other analytes include indicators of and drugs for treatment of anemia including EPO, ferritin, folate, Intrinsic Factor Ab, soluble transferrin receptor, and vitamin B12. Other analytes include intact PTH, bone alkaline phosphatase, and hGH for assessing bone metabolism. In some embodiments, analytes for assessing thyroid function include free and total T3, free and total T4, TSH, thyroglobulin, thyroglobulin Ab and TPO Ab. Other analytes include tumor markers AFP, BPHA, CA 15-3 antigen, CEA, CA 19-9 antigen, PSA, and CA 125 antigen. Infectious disease analytes include CMV IgG and IgM, Rubella IgG and IgM, Toxoplasmosis IgG and IgM, HAV Ab and IgM, HBc Ab and IgM, Hbe Ab and Antigen, HBs Ab and Antigen, and HCV Ab.
[0051] Any appropriate peroxidase enzyme may be used in the methods provided herein. Peroxidase enzymes reduce hydrogen peroxide to water while oxidizing a variety of substrates. Exemplary peroxidase enzymes include a horseradish peroxidase enzyme, a peanut peroxidase enzyme, a barley grain peroxidase enzyme, an ascorbate peroxidase enzyme, a fungal peroxidase or a cytochrome-C peroxidase enzyme. In some embodiments, the peroxidase enzyme is a horseradish peroxidase.
[0052] The choice of solid support for use in the present methods is based upon the desired assay format and performance characteristics. Acceptable solid supports for use in the present methods can vary widely. A solid support can be porous or nonporous. It can be continuous or non-continuous, and flexible or nonflexible. A solid support can be made of a variety of materials including ceramic, glass, metal, organic polymeric materials, or combinations thereof. Moreover, the solid support provided herein may be a magnetic solid support. The magnetic solid support may be composed at least in part of a magnetically responsive component such as a magnetic particle. Magnetic particles can have a solid core portion that is magnetically responsive and is surrounded by one or more non-magnetically responsive layers. Magnetically responsive components include magnetically responsive materials such as ferromagnetic, paramagnetic and superparamagnetic materials. One exemplary magnetically responsive material is magnetite.
[0053] The solid support may further be coated with one or more coating particles. Such coating particles may function to provide reactive groups to conjugate the chemiluminescent moiety to the solid support. The chemiluminescent moiety may be connected to the solid support by reacting a reactive group of the linking moiety with a reactive group of the solid support. Reactive groups are further discussed below. In some embodiments, the coating particles may include BSA providing sulfhydryl, amino or carboxyl groups as reactive groups. In certain embodiments, the coating particles form at least part of a coating layer on the solid support.
[0054] A peroxide-generating enzyme is an enzyme that catalyzes the oxidation or reduction reaction of a variety of substrates involving molecular oxygen as the electron acceptor. In such reactions oxygen is reduced to hydrogen peroxide or a combination of water and hydrogen peroxide. The generated hydrogen peroxide is then reduced to water by the peroxidase enzyme in the present reaction system. Examples of peroxide generating enzymes used in the embodiments presented include, but are not limited to, glucose oxidase, glycollate oxidase, hexose oxidase, cholesterol oxidase, aryl-alcohol oxidase, L-gulonolactone oxidase, galactose oxidase, pyranose oxidase, L-sorbose oxidase, pyridoxine oxidase, alcohol oxidase, L-2-hydroxy-acid oxidase, ecdysome oxidase, choline oxidase, aldehyde oxidase, xanthine oxidase, pyruvate oxidase, oxalate oxidase, glyoxylate oxidase, pyruvate oxidase, D-aspartate oxidase, L-aminoacid oxidase, amine oxidase, pyridoxaminephosphate oxidase, D-glutamate oxidase, ethanolamine oxidase, tyramine oxidase, putrascine oxidase, sarcosine oxidase, N-methylaminoacid oxidase, N-methyl-lysine oxidase, hydroxylnicotine oxidase, nitroethane oxidase, acetyl-indoxyl oxidase, urate oxidase, hydroxylamine oxidase, or sulphite oxidase. Any appropriate peroxide generating enzyme substrate may be used during the reduction or oxidation reaction catalyzed by the peroxidase generating enzyme. Examples for peroxide generating enzyme substrates are glucose, glycollate, hexose, cholesterol, aryl-alcohol, L-gulonolactone, galactose, pyranose, L-sorbose, pyridoxine, alcohol, L-2-hydroxy-acid, ecdysome, choline, aldehyde, xanthine, pyruvate, oxalate, glyoxylate, pyruvate, D-aspartate, L-aminoacid, amine, pyridoxaminephosphate, D-glutamate, ethanolamine, tyramine, putrascine, sarcosine, N-methylaminoacid, N-methyl-lysine, hydroxylnicotine, nitroethane, acetyl-indoxyl, urate, hydroxylamine, or sulphite. The reaction of a peroxide generating enzyme with a corresponding peroxide generating enzyme substrate results in oxidation or reduction of the peroxide generating enzyme substrate and production of hydrogen peroxide due to the reduction of oxygen. One of skill will immediately identify the corresponding substrates and enzymes listed above (e.g. the substrate for oxalate oxidase is oxalate). In some embodiments, glucose oxidase may be used as the peroxide generating enzyme to react with glucose as the peroxide generating enzyme substrate thereby reducing oxygen to hydrogen peroxide. Hydrogen peroxide may then be reduced to water by a peroxidase enzyme. Therefore, in some embodiments, the peroxide generating enzyme is glucose oxidase and the peroxide generating enzyme substrate is glucose.
[0055] As described above, in some embodiments, the detectable solid support bound analyte complex is contacted with a peroxidase enhancer compound. Typically the peroxidase enhancer compound is present when the detectable solid support bound analyte complex is contacted with the peroxide generating enzyme substrate thereby producing peroxide. Without being limited by any particular mechanistic theory, it is believed that an oxidized peroxidase enhancer compound is generated from a peroxidase enhancer compound when the peroxidase enzyme reacts with hydrogen peroxide. The oxidized peroxidase enhancer compound may promote the catalytic activity of the peroxidase with a chemiluminescent compound during the process of generating luminescence. Thus, peroxidase enhancer compounds may be contacted with a detectable solid support bound analyte complex when the peroxide generating enzyme substrate is added. In the methods described herein, a peroxidase enhancer compound may include a phenolic moiety. In some embodiments, the peroxidase enhancer may be p-phenylphenol, p-iodophenol, p-bromophenol, p-hydroxycinnamic acid, p-imidazolylphenol, acetaminophen, 2,3,-dichlorophenol, 2-naphthol, or 6-bromo-2-naphthol or other art-known enhancers. Included among the enhancers for use herein are phenolic compounds and aromatic amines known to enhance other peroxidase reactions as described in U.S. Pat. Nos. 5,171,668 and 5,206,149. Substituted and unsubstituted arylboronic acid compounds and their ester and anhydride derivatives as disclosed in U.S. Pat. No. 5,512,451 are another class of compounds considered to be within the scope of enhancers useful in the present methods. Derivatives of phenoxazine and phenothiazine including 3-(N-phenothiazinyl)-propanesulfonic acid salts, 3-(N-phenoxazinyl)propanesulfonic acid salts, 4-(N-phenoxazinyl)butanesulfonic acid salts, 5-(N-phenoxazinyl)-pentanoic acid salts and N-methylphenoxazine and related homologs represent another useful group of enhancer compounds.
[0056] The first analyte binder and the second analyte binder may be binding proteins such as, but not limited to, antibodies, antibody fragments, antibody-DNA chimeras, antigens, haptens, peptides, hormone receptors, protein A, lectin, avidin, streptavidin and biotin. In some embodiments, the first analyte binder and the second analyte binder are binding proteins. In other embodiment, the first analyte binder and the second analyte binder are antibodies.
[0057] Again, without being limited by any particular mechanistic theory, it is believed that chemiluminescence is the emission of light as the result of a chemical reaction. In the presence of a suitable catalyst a chemiluminescent compound may be transferred into a higher state of energy due to the transfer of energy from a second reaction partner. The decay of the excited state of the chemiluminescent compound to a lower energy level may result in the emission of light. Upon relaxation to a ground state the chemiluminescent compound may either directly emit light or may transfer the excitation energy to an emissive energy acceptor, which is the source of light emission. The chemiluminescent compound useful herein typically comprises a chemiluminescent moiety, which may be transferred into a higher state of energy and a linking moiety for coupling to another material. The chemiluminescent moiety includes each class of compounds described above including, but not limited to, luminal and structurally related cyclic hydrazides, acridan esters, thioesters and sulfonamides, and acridan ketenedithioacetal compounds. In some embodiments, the chemiluminescent compound includes a chemiluminescent acridan moiety. Acridans represent compounds that react either directly or indirectly with a peroxidase enzyme and/or peroxide to produce a chemiluminescent signal. The following patents disclose chemiluminescent acridan moietie useful in the methods provided herein: U.S. Pat. Nos. 5,491,072, 5,523,212, 5,593,845, 5,750,698, 6,858,733, 6,872,828 and 7,247,726.
[0058] During the process of hydrogen peroxide decomposition water and oxygen are produced either spontaneously or due to the presence of a decomposition agent. Decomposition agents catalyze the decomposition of peroxide to water and oxygen thereby removing excess peroxide from the reaction. Thus, background signal is reduced during analysis involving use of peroxidase conjugated analyte binders. The detectable solid support bound analyte complex may contacted with a peroxide decomposition agent for background signal reducing purposes. Therefore, in some embodiments, the detectable solid support bound analyte complex is contacted with a peroxide decomposition agent. In other embodiments, the detectable solid support bound analyte complex is contacted with the peroxide decomposition agent before being contacted with the peroxide generating enzyme substrate and the production of peroxide. The decomposition agents provided herein may be aromatic hydrocarbons or their derivatives. The decomposition agent may also be an enzyme that is able to react with hydrogen peroxide to produce water and oxygen. In some embodiments, the decomposition agent is an enzyme. In other embodiments, the decomposition agent is a catalase. In some embodiments, the catalase is present with the detectable solid support bound analyte complex at concentrations between 0.1 to 10 μg/ml. In other embodiments, the catalase is present with the detectable solid support bound analyte complex at concentrations between 0.5 to 5 μg/ml. In other embodiments, the catalase is present with the detectable solid support bound analyte complex at a concentration of about 2 μg/ml (e.g. 2 μg/ml). The catalase enzyme may be derived from prokaryotic or eukaryotic cells. In some examples, catalase enzymes are derived from human erythrocytes. Further, the catalase enzyme may be derived from murine, bovine or bison liver.
[0059] It is sometimes desirable to detect an analyte in a sample using competition binding assays. During such competition binding assays the first or second analyte binder (which is conjugated to a solid support conjugate) interacts with a competition analyte. A competition analyte is a binding partner able to interact with the first or second analyte binder. The term competition analyte refers to, but is not limited to, a binding partner such as a protein, peptide or antibody that is able to interact with the first or second analyte binder. Among other things, the competition analyte may be a carbohydrate, peptide, protein, nucleic acid or drug (e.g. a hormone, cytokine, enzyme substrate, viruses, biomolecules, or small molecule modulator). In some embodiments, the competition analyte is a purified form of an analyte found in nature or a synthetic version of the analyte (e.g. an analyte produced chemically or using recombinant techniques). In other embodiments, the competition analyte is a competition analyte analog. A competition analyte analog is a binding partner with properties that enable the competition analyte analog to compete with the analyte for interaction with the first or second analyte binder. Examples of competition analyte analogs are nucleic acid analogs such as peptide nucleic acid (PNA) or conjugated polymers with DNA-mimetic properties, nonnatural and natural peptide analogs, peptide mimetics that biologically mimic active determinants on hormones, cytokines, enzyme substrates, viruses or other bio-molecules, and small molecule modulators (such as those having high affinity to the ATP binding site of ATP-dependent enzymes).
[0060] Subsequent to binding the first or second analyte binder, the competition analyte competes with the analyte for interaction with the second or first analyte binder, respectively. A detectable solid support bound analyte complex may be formed upon binding of the competition analyte to the first analyte binder and the second analyte binder. However, if the analyte is bound to either the first or the second analyte binder within this competition binding assay, a detectable solid support bound analyte complex may be prevented from forming. Therefore, in the competition binding assays presented herein, lower amounts of analyte result in a stronger chemiluminescent signal, whereas higher concentrations of analyte result in a weaker chemiluminescent signal.
[0061] In one aspect, the method includes contacting the analyte with a solid support conjugate and a first analyte binder conjugate. The first analyte binder conjugate is a peroxidase enzyme conjugated to a first analyte binder where the first analyte binder is bound to a competition analyte. The solid support conjugate includes a solid support conjugated to a second analyte binder, a peroxide generating enzyme, and a chemiluminescent compound. The binding of the first analyte binder conjugate, which includes the competition analyte, to the second analyte binder forms a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal insofar as the amount of analyte correlates inversely to the intensity of the chemiluminescent signal. Thus, detecting the chemiluminescent signal may include detecting a lower amount of chemiluminescent signal or absence of chemiluminescent signal.
[0062] In another embodiment, the method includes contacting the analyte with a solid support conjugate and a first analyte binder conjugate. The first analyte binder conjugate is a peroxidase enzyme conjugated to a first analyte binder. The solid support conjugate includes a solid support conjugated to a peroxide generating enzyme, a chemiluminescent compound and a second analyte binder where the second analyte binder is bound to a competition analyte. The binding of the first analyte binder conjugate to the solid support conjugate, which includes the competition analyte, forms a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal insofar as the amount of analyte correlates inversely to the intensity of the chemiluminescent signal. Thus, detecting the chemiluminescent signal may include detecting a lower amount of chemiluminescent signal or absence of chemiluminescent signal.
[0063] In one aspect, the method includes contacting the analyte, or a sample including the analyte, with a solid support conjugate and a first analyte binder conjugate. The first analyte binder conjugate is a peroxidase enzyme conjugated (e.g. covalently bound) to a competition analyte. The competition analyte may be directly conjugated to the peroxidase enzyme or linked through a bifunctional linker. The solid support conjugate includes a solid support conjugated to a peroxide generating enzyme, a chemiluminescent compound and a second analyte binder. The binding of the first analyte binder conjugate, which includes the competition analyte conjugated to the peroxidase enzyme, to the solid support conjugate forms a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal insofar as the amount of analyte correlates inversely to the intensity of the chemiluminescent signal. Thus, detecting the chemiluminescent signal may include detecting a lower amount of chemiluminescent signal or absence of chemiluminescent signal.
[0064] In another aspect, the method includes contacting the analyte with a solid support conjugate and a first analyte binder conjugate. The first analyte binder conjugate is a peroxidase enzyme conjugated to a first analyte binder. The solid support conjugate includes a competition solid support conjugate which includes a solid support conjugated to a peroxide generating enzyme, a chemiluminescent compound, and a competition analyte that is covalently bound to the solid support. The competition analyte may be directly conjugated to the solid support or through a bifunctional linker. The binding of the first analyte binder conjugate to the competition solid support conjugate forms a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal insofar as the amount of analyte correlates inversely to the intensity of the chemiluminescent signal. Thus, detecting the chemiluminescent signal may include detecting a lower amount of chemiluminescent signal or absence of chemiluminescent signal.
[0065] In another aspect, the method includes contacting the analyte with a solid support conjugate and an analyte-peroxidase conjugate. The analyte-peroxidase conjugate is a peroxidase enzyme conjugated to the analyte or a homolog of the analyte. The solid support conjugate includes a solid support conjugated to a peroxide generating enzyme, a chemiluminescent compound, and a first analyte binder that is covalently bound to the solid support. The first analyte binder may be directly conjugated to the solid support or through a bifunctional linker. The binding of the first analyte binder to the analyte-peroxidase conjugate forms a detectable solid support bound analyte complex. The detectable solid support bound analyte complex is contacted with a peroxide generating enzyme substrate thereby producing a peroxide. The peroxidase enzyme is allowed to react with the peroxide which results in the activation of the chemiluminescent compound and the production of a chemiluminescent signal. The analyte is detected by detecting the chemiluminescent signal insofar as the amount of analyte correlates inversely to the intensity of the chemiluminescent signal. Thus, detecting the chemiluminescent signal may include detecting a lower amount of chemiluminescent signal or absence of chemiluminescent signal.
[0066] In one aspect, a solid support conjugate is provided and the solid support conjugate includes a solid support conjugated to a chemiluminescent compound, a hydrogen peroxide generating enzyme, and an analyte binder. In some embodiments, the analyte binder is an antibody. In other embodiments, the hydrogen peroxide generating enzyme is a glucose oxidase. In other embodiments, the chemiluminescent compound includes a chemiluminescent acridan moiety. In some embodiments, the chemiluminescent compound has the formula:
[0000]
[0067] R 1 and R 2 may independently be substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, or substituted or unsubstituted aralkyl. R 3 is substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, alkoxyalkyl, carboxyalkyl or alkylsulfonic acid. R 3 is optionally joined with R 7 or R 8 to form a 5 or 6-membered ring. R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 are independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, aralkyl, alkenyl, alkynyl, alkoxy, aryloxy, halogen, amino, substituted amino, substituted or unsubstituted carboalkoxy, carboxamide, cyano, or sulfonate. Pairs of adjacent groups of R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 are optionally joined to form a carbocyclic or heterocyclic ring system. At least one of the groups of R 1 to R 11 includes a linking moiety. In one embodiment, each of R 4 to R 11 is H.
[0068] R 1 and R 2 in the compound of formula I can be any organic group containing from 1 to about 50 non hydrogen atoms selected from C, N, O, S, P, Si and halogen atoms which allows light production. By the latter is meant that when a compound of formula I undergoes a reaction of set forth in the methods provided herein, an excited state product compound is produced and can involve the production of one or more chemiluminescent intermediates. The excited state product can emit the light directly or can transfer the excitation energy to a fluorescent acceptor through energy transfer causing light to be emitted from the fluorescent acceptor. In one embodiment R 1 and R 2 are selected from substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, and substituted or unsubstituted aralkyl groups of 1-20 carbon atoms. When R 1 or R 2 are substituted, it can be substituted with 1-3 groups selected from carbonyl groups, carboxyl groups, tri(C 1 -C 8 alkyl)silyl groups, a SO 3 − group, a OSO 3 −2 group, glycosyl groups, a PO 3 − group, a OPO 3 −2 group, halogen atoms, a hydroxyl group, a thiol group, amino groups, quaternary ammonium groups, and quaternary phosphonium groups.
[0069] R 3 is an organic group containing from 1 to 50 non-hydrogen atoms selected from C, N, O, S, P, Si and halogen in addition to the necessary number of H atoms required to satisfy the valences of the atoms in the group. In one embodiment, R 3 contains from 1 to 20 non-hydrogen atoms. In another embodiment, the organic group is selected from the group consisting of alkyl, substituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, and substituted or unsubstituted aralkyl groups of 1 to 20 carbon atoms. In another embodiment, R 3 includes substituted or unsubstituted C 1 -C 4 alkyl groups, phenyl, substituted or unsubstituted benzyl groups, alkoxyalkyl, carboxyalkyl and alkylsulfonic acid groups. R 3 can be joined to either R 7 or R 8 to complete a 5 or 6-membered ring. In one embodiment, R 3 is substituted with a linking moiety.
[0070] In the compounds of Formula (I), R 4 to R 11 each are independently H or a substituent which permits the excited state product to be produced and generally contain from 1 to 50 atoms selected from C, N, O, S, P, Si and halogens. Representative substituents which can be present include, without limitation, alkyl, substituted alkyl, aryl, substituted aryl, aralkyl, alkenyl, alkynyl, alkoxy, aryloxy, halogen, amino, substituted amino, carboxyl, carboalkoxy, carboxamide, cyano, and sulfonate groups. Pairs of adjacent groups, e.g., R 4 to R 5 or R 5 to R 6 , can be joined together to form a carbocyclic or heterocyclic ring system comprising at least one 5 or 6-membered ring which is fused to the ring to which the two groups are attached. Such fused heterocyclic rings can contain N, O or S atoms and can contain ring substituents other than H such as those mentioned above. One or more of the groups R 4 to R 11 can be a linking moiety. In one embodiment, R 4 to R 11 are selected from hydrogen, halogen and alkoxy groups such as methoxy, ethoxy, t-butoxy and the like. In another embodiment, a group of compounds has one of R 5 , R 6 , R 9 or R 10 as a halogen and the other of R 4 to R 11 are hydrogen atoms.
[0071] Substituents can be incorporated in various quantities and at selected ring or chain positions in the acridan ring in order to modify the properties of the chemiluminescent compound or to provide for convenience of synthesis. Such properties include, e.g., chemiluminescence quantum yield, rate of reaction with the enzyme, maximum light intensity, duration of light emission, wavelength of light emission and solubility in the reaction medium. Specific substituents and their effects are illustrated in the specific examples below, which, however, are not to be considered limiting the scope of the invention in any way. For synthetic expediency compounds of formula I desirably have each of R 4 to R 11 as a hydrogen atom.
[0072] In another embodiment, the chemiluminescent compound has the formula:
[0000]
[0073] In some embodiments, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 are hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, a linking moiety (-L-), or a substituent comprising a linking moiety (-L-). At least one of R 1 to R 11 includes a linking moiety or is a linking moiety (-L-). The linking moiety (-L-) is a bond, the reaction product of two reactive groups, substituted or unsubstituted alkylene, substituted or unsubstituted heteroalkylene, substituted or unsubstituted cycloalkylene, substituted or unsubstituted heterocycloalkylene, substituted or unsubstituted arylene, or substituted or unsubstituted heteroarylene. In some embodiment, R 1 and R 2 are not hydrogen. In other embodiments, R 1 or R 2 are -L- or comprise -L-. The groups R 1 , R 2 and R 3 are as defined above, in the compounds of Formula (I). In some embodiments, the compound of Formulas (I) or (II) have a linking moiety as a substituent on the R 1 or R 2 group. In some embodiments, the chemiluminescent moiety is an acridan kentenedithioacetal.
[0074] The linking moiety connects the chemiluminescent moiety to the solid support. The linking moiety may be attached to the solid support through a covalent bond. The covalent bond may be formed by contacting a reactive group on a linking moiety precursor with a reactive group on a solid support precursor. The solid support precursor may include a spacer moiety with a reactive group in order to increase chemical accessibility to the linking moiety precursor reactive group. By reacting the reactive groups of the linking moiety precursor and the solid support precursor, the chemiluminescent moiety is connected to the solid support. Exemplary classes of reactions are those proceeding under relatively mild conditions. These include, but are not limited to nucleophilic substitutions (e.g., reactions of amines and alcohols with acyl halides, active esters), electrophilic substitutions (e.g., enamine reactions), and additions to carbon-carbon and carbon-heteroatom multiple bonds (e.g., Michael reaction, Diels-Alder addition). These and other useful reactions are discussed in, for example, March, Advanced Organic Chemistry, 3rd Ed., John Wiley & Sons, New York, 1985; Hermanson, Bioconjugate Techniques, Academic Press, San Diego, 1996; and Feeney et al., Modification of Proteins; Advances in Chemistry Series, Vol. 198, American Chemical Society, Washington, D.C., 1982.
[0075] Useful reactive groups include, for example: (a) carboxyl groups and derivatives thereof including, but not limited to activated esters, e.g., N-hydroxysuccinimide esters, N-hydroxybenztriazole esters, acid halides, acyl imidazoles, thioesters, p-nitrophenyl esters, alkyl, alkenyl, alkynyl and aromatic esters, activating groups used in peptide synthesis and acid halides; (b) hydroxyl groups, which can be converted to esters, sulfonates, phosphoramidites, ethers, aldehydes, etc.; (c) haloalkyl groups, wherein the halide can be displaced with a nucleophilic group such as, for example, an amine, a carboxylate anion, thiol anion, carbanion, or an alkoxide ion, thereby resulting in the covalent attachment of a new group at the site of the halogen atom; (d) dienophile groups, which are capable of participating in Diels-Alder reactions such as, for example, maleimido groups; (e) aldehyde or ketone groups, allowing derivatization via formation of carbonyl derivatives, e g, imines, hydrazones, semicarbazones or oximes, or via such mechanisms as Grignard addition or alkyllithium addition; (f) sulfonyl halide groups for reaction with amines, for example, to form sulfonamides; (g) thiol groups, which can be converted to disulfides or reacted with acyl halides, for example; (h) amine or sulfhydryl groups, which can be, for example, acylated, alkylated or oxidized; (i) alkenes, which can undergo, for example, cycloadditions, acylation, Michael addition, etc; (j) epoxides, which can react with, for example, amines and hydroxyl compounds; and (k) phosphoramidites and other standard functional groups useful in nucleic acid synthesis. In an exemplary embodiment, the solid support precursor includes a reactive amine and the linking moiety precursor includes a reactive carboxyl group. The solid support precursor is then covalently bonded to the linking moiety precursor using any appropriate amide bond forming agent, such as those used in the art of peptide synthesis.
[0076] The reactive groups can be chosen such that they do not participate in, or interfere with, the reactions necessary to assemble or utilize the chemiluminescent moiety. Alternatively, a reactive group can be protected from participating in the reaction by the presence of a protecting group. Those of skill in the art understand how to protect a particular functional group such that it does not interfere with a chosen set of reaction conditions. For examples of useful protecting groups, see, for example, Greene et al., Protective Groups in Organic Synthesis, John Wiley & Sons, New York, 1991.
[0077] In some cases attachment will not involve covalent bond formation, but rather physical forces in which case the linking group remains unaltered. Physical forces imply attractive forces such as hydrogen bonding, electrostatic or ionic attraction, hydrophobic attraction such as base stacking, and specific affinity interactions such as biotin-streptavidin, antigen-antibody and nucleotide-nucleotide interactions.
[0078] In addition to the reactive group the linking moiety precursor and or solid support precursor may further include a spacer. In some embodiments, the spacer is on one or both sides of the bond formed by the reaction of the reactive group. The spacer may be a substituted or unsubstituted alkylene, substituted or unsubstituted heteroalkylene, substituted or unsubstituted cycloalkylene, substituted or unsubstituted heterocycloalkylene, substituted or unsubstituted arylene, or substituted or unsubstituted heteroarylene. In another related embodiment, the spacer is selected from C 1 -C 10 substituted or unsubstituted alkylene, 2 to 10 membered substituted or unsubstituted heteroalkylene, C 3 -C 8 substituted or unsubstituted cycloalkylene, and 3 to 8 membered substituted or unsubstituted heterocycloalkylene. The spacer can be further defined as a bond, an atom, divalent groups and polyvalent groups, a straight or branched chain of atoms some of which can be part of a ring structure. The straight or branched chain can be substituted or unsubstituted and can be an alkylene or a heteroalkylene. The substituent usually contains from 1 to about 50 non-hydrogen atoms, more usually from 1 to about 30 non-hydrogen atoms. Examples for atoms included in the chain are selected from, but not limited to C, O, N, S, P, Si, B, and Se atoms. In another embodiment atoms comprising the chain are selected from C, O, N, P and S atoms. The number of atoms other than carbon in the chain is normally from 0-10. Halogen atoms can be present as substituents on the chain or ring.
[0079] In some embodiments, a linking moiety may conjugate a competition analyte to an analyte binder, which can be a first or a second analyte binder, or to a solid support. Such linking moiety is referred to herein as a bifunctional linker. The bifunctional linker includes reactive groups at the point of attachment contacting the competition analyte and reactive groups at the point of attachment contacting the solid support or the analyte binder. The reactive groups at either point of attachment of the bifunctional linker may be separated by a spacer as previously described. The reactive groups at both points of attachment of the bifunctional linker may react with the corresponding reactive groups of the competition analyte and the solid support or the competition analyte and the analyte binder. Thus, the competition analyte is conjugated to the solid support or the analyte binder. Any of the linking moieties and reactive groups previously described may be used to conjugate the competition analyte to the analyte binder or the solid support.
[0080] Kit embodiments provide a convenient means for supplying necessary reagents of the invention, ancillary reagents, apparatuses, instructions and/or other components necessary to implement the invention. In one aspect, a kit for detecting an analyte in a sample is provided.
[0081] The kit includes a first analyte binder conjugate that is conjugated to a peroxidase enzyme, and a solid support conjugate that is conjugated to a second analyte binder, a peroxide generating enzyme, and a chemiluminescent compound. In some embodiments, the kit includes a solution containing the peroxide generating enzyme substrate. The kit may include a peroxidase enhancer compound. In some embodiments, the peroxidase enhancer compound is p-phenylphenol, p-iodophenol, p-bromophenol, p-hydroxycinnamic acid, p-imidazolylphenol, acetaminophen, 2,3,-dichlorophenol, 2-naphthol, or 6-bromo-2-naphthol. In one embodiment, the chemiluminescent compound in the kit includes a chemiluminescent acridan moiety. In some embodiments, the chemiluminescent acridan moiety is a acridan ketenedithioacetal. The first analyte binder and the second analyte binder included in the kit may be antibodies. The kit may include a solution containing a peroxide decomposition agent. In some embodiments, the peroxide decomposition agent of the kit is a catalase.
[0082] Other materials useful in the performance of the assays can also be included in the kit, including test tubes, transfer pipettes, and the like. The kit may also include written instructions for the use of one or more of the reagents described herein. The invention contemplates additional kits packaged to deliver, instruct and otherwise aid the practitioner in the use of the invention. These additional kits include those for the use of diagnostic embodiments of the invention, and their construction is well known by those of skill in the art provided with the reagents set forth herein.
Detection
[0083] Light emitted by the present method can be detected by any suitable known means such as a luminometer, x-ray film, high speed photographic film, a CCD camera, a scintillation counter, a chemical actinometer or visually. Each detection means has a different spectral sensitivity. The human eye is optimally sensitive to green light, CCD cameras display maximum sensitivity to red light, X-ray films with maximum response to either UV to blue light or green light are available. Choice of the detection device will be governed by the application and considerations of cost, convenience, and whether creation of a permanent record is required. In those embodiments where the time course of light emission is rapid, it is advantageous to perform the triggering reaction to produce the chemiluminescence in the presence of the detection device. As an example the detection reaction may be performed in a test tube or microwell plate housed in a luminometer or placed in front of a CCD camera in a housing adapted to receive test tubes or microwell plates.
[0084] In some embodiments, light is measured in an instrument for performing assays. Such an instrument comprises one or more reaction vessels for performing assays. The reaction vessels may comprise disposable wells, tubes or cartridges into which are dispensed samples and other reagents needed for performing tests. The instrument may further comprise pumps and injectors for dispensing liquids and particles. The instrument may further comprise means for transporting reaction vessels to one or more zones within the instrument. The instrument further comprises a light measurement device, typically a photomultiplier, as well as means for recording one or more characteristics of the light produced by a sample in an assay. The instrument may further comprise a data collection, analysis and storage system, typically a computer. Characteristics of the light that may be measured in an assay include peak intensity, integrated intensity for some or all of the light emitting period, rate of change of light intensity, spectral distribution, ratio of intensity at more than one wavelength, time to achieve peak intensity, or time to achieve some fraction of peak intensity.
Uses
[0085] The present assay methods find applicability in many types of specific binding pair assays. Foremost among these are chemiluminescent enzyme linked immunoassays, such as an ELISA. Various assay formats and the protocols for performing the immunochemical steps are well known in the art and include both competitive assays and sandwich assays. Types of substances that can be assayed by immunoassay according to the present methods include proteins, peptides, antibodies, haptens, drugs, steroids and other substances that are generally known in the art of immunoassay.
[0086] The methods provided herein are also useful for the detection of nucleic acids. The presented methods may use enzyme-labeled nucleic acid probes. Exemplary methods include solution hybridization assays, DNA detection in Southern blotting, RNA by Northern blotting, DNA sequencing, DNA fingerprinting, colony hybridizations and plaque lifts, the conduct of which is well known to those of skill in the art.
[0087] In addition to the aforementioned antigen-antibody, hapten-antibody or antibody-antibody pairs, specific binding pairs also can include complementary oligonucleotides or polynucleotides, avidin-biotin, streptavidin-biotin, hormone-receptor, lectin-carbohydrate, IgG protein A, binding protein-receptor, nucleic acid-nucleic acid binding protein and nucleic acid-anti-nucleic acid antibody. Receptor assays used in screening drug candidates are another area of use for the present methods.
III. Examples
[0088] The following example demonstrates an immunoassay of an analyte, Prostate Specific Antigen (PSA), wherein hydrogen peroxide is generated through the reaction of glucose oxidase with glucose, where the glucose oxidase is bound with the surface of the solid phase.
[0089] The antibodies used for this example were those found in the Hybritech® PSA Assay (Item No. 37200) of the Access® Immunoassay System (Beckman Coulter, Inc., Fullerton, Calif., USA). The antibodies in the described embodiment are used in the same orientation, that is, the Hybritech® solid phase capture antibody is located on the solid phase support surface and the Hybritech® conjugate antibody is used for the peroxidase conjugate. It should be noted that while this experiment utilized the Hybritech® PSA antibodies one skilled in the art will recognize that other suitable antibody pairs could be substituted so long as such antibody pair provided the ability to form a specific binding pair sandwich with the analyte antigen. Unique buffers are described. Buffers not described are obvious to one skilled in the art.
[0000]
[0090] To prepare the base microparticles Bovine Serum Albumin (BSA) was biotinylated with 4× molar excess of biotin-LC-sulfoNHS (Pierce Biotechnology Inc., Rockford, Ill., USA). Unbound reactants were removed via desalting or dialysis. The biotin-BSA was then reacted with a 5× molar excess of Compound 17 in 20 mM sodium phosphate pH 7.2: DMSO 75:25, v/v) followed by desalting in the same buffer. The dual labeled (biotin and 17) BSA was then coupled with tosyl activated M280 microparticles (Invitrogen Corporation, Carlsbad, Calif., USA) in a 0.1M borate buffer pH 9.5 at a concentration of ca. 20 μg labeled BSA per mg of microparticles for 16-24 h at 40° C. After coupling the microparticles were stripped for 1 h at 40° C. with 0.2 M TRIS base, 2% SDS, pH ˜11. The stripping process was repeated one additional time. Microparticles were then suspended in a 0.1% BSA/TRIS buffered saline (BSA/TBS) buffer and streptavidin (SA) was added at approximately 15 μg SA per mg microparticles. Streptavidin was mixed with the microparticles for 45-50 min at room temperature. The microparticles were then washed three times and suspended in the same BSA/TBS. This describes the preparation of the base microparticles. Internal studies have shown these base microparticles are capable of binding approximately 5 μg of biotinylated capture antibody per mg of microparticles.
[0091] To prepare the actual test microparticles glucose oxidase (GOX), obtained from Sigma Aldrich, St. Louis, Mo., USA was biotinylated with a 5× molar excess of biotin-PEO 4 —NHS, obtained from Pierce Biotechnology Inc., Rockford, Ill., USA. Unbound reactants were removed by desalting or dialysis. The PSA capture antibody was also biotinylated with a 5× molar excess of biotin-LC-sulfoNHS, (Pierce) and unbound reactants were removed by desalting or dialysis. To the base microparticles (above) the biotin capture antibody was added at 4 μg per mg of microparticles and the biotin GOX was added at 1 μg per mg of microparticles. The biotinylated proteins were mixed with the microparticles overnight at room temperature. After incubating all unbound reactants were removed by three washes in BSA/TBS.
[0092] The second analyte-specific binding partner, or antibody was prepared by first the activation of the Hybritech antibody with a 50× molar excess of DL-N-Acetylhomocysteine thiolactone (AHTL; Sigma-Aldrich) in 0.1M carbonate pH 9 for 1 h at room temperature. Excess reactant was removed by desalting into PBS plus 1 mM EDTA. At the same time HRP, (Roche Diagnostics, Indianapolis, Ind., USA) was activated with a 10× molar excess of sulfo-SMCC, (Pierce) for 1 h at room temperature. Excess reactant was removed by desalting into PBS. The activated Hybritech antibody and HRP were mixed together in a 1:5 (Ab:HRP) molar ratio and are allowed to react at room temperature for 1-2 hours. The reaction was stopped by the addition of a slight molar excess of 2-mercaptoethanol, then N-ethyl maleimide. The antibody-HRP second analyte-specific binding partner was then separated from unbound reactants by SEC. Trigger solution consisted of 0.1M sodium phosphate pH ˜7.2, 0.2M glucose, and 8 mM p-hydroxycinnamic acid.
[0093] To perform an assay the following stocks were prepared from the above described components. Microparticles were diluted to 1.75 mg/mL in BSA/TBS. Conjugate was diluted to 2 μg/mL in BSA/TBS. The reaction mixture was prepared by mixing the microparticle stock, a conjugate stock, buffer, and sample in the following ratio: 25:45:15:15 (volumes ratio of Microparticles:BSA/TBS:Conjugate:Sample) in this written order. The reaction mixture was incubated for 30 min at 37° C., then 100 μL of trigger solution was added and the light intensity recorded. To evaluate the effect of catalase (Sigma-Aldrich) the enzyme was added to the BSA/TBS added to the reaction at a concentration of 2 μg/ml.
[0094] Signal (light) was captured and quantified immediately after addition of the trigger solution with a PMT. The signal expressed as relative luminometer (light) units RLUs is provided in the following table.
[0000]
PSA
Average RLU
(ng/mL)
−catalase
+catalase
0
1011
491
0.5
1184
1860
2
2054
712
10
3214
2532
75
15887
9792
150
21935
18878 | Nonseparation assay methods using peroxide generating enzymes in combination with a solid support for analyte detection are disclosed. The present assay methods provide a high degree of sensitivity, are simple and efficient to perform, and are excellent tools for diagnostic and high through-put screening applications. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of PCT application PCT/IN06/000344 having a 371(c) filing date of Sep. 11, 2006.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
Not applicable.
INCORPORATION BY REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not applicable.
BACKGROUND OF THE INVENTION
Whereas multi level automatic car parking has become a basic infrastructure in the current economic development, besides the demand of fast and safe parking and retrieval, the over dimensional platform carriers, that too in large numbers, posed a challenge for handling and storage. There is a time gap between handling two successive cars. When a number of vehicles report simultaneously for parking as it happens during opening peak hours, the pressure on the system is so much as to cause a virtual breakdown. Cars reporting for parking have to wait in queue causing irritation to clients besides creating traffic congestion. Similarly, when the requests for retrievals pour in heavily at the closing hours, the system becomes unmanageable and goes haywire. So far no workable solution has emerged with the result that the growth of the multi level automatic parking units is hindered.
DESCRIPTION OF RELATED ART INCLUDING INFORMATION DISCLOSED UNDER 37 CFR 1.97 AND 1.98
U.S. Pat. No. 5,024,571, dated Jun. 18, 1991, stipulates one elevator for every entry and exit. The prior art thus deploys quite a good number of elevators to answer the simultaneous requests for parking and delivery. This has limitations and further adversely affects cost effectiveness and space saving. There are separate exit and entry points in the prior arts, and the transfer of platform carriers from exit to entry point is cumbersome. Some vague attempts have been tried by providing a multi-tier storage inside the elevator. Further, guide rails in each parking slot presents a challenge in alignment and maintenance. Solutions which include endless chain drives, or catching “dog drives”, include a number of linkages that incorporate more potential points of failure, in addition to requiring substantial maintenance.
U.S. Pat. No. 3,984,012, dated Oct. 5, 1976, also deploys guiderails in each parking slot and suggests highly complicated technology to provide a sliding mechanism for bridging the gap between the guide ways on the parking slot and that on the transfer platform. Further, the pallets handling mechanism is cumbersome.
German Patent DE 93 05 367.3, dated Oct. 14, 1993, brings out the demands on the system, but fails to suggest suitable means to achieve the results, especially peak-hour traffic management. The suggestion of several units and the suggestion of pallets handling by slide wagons in the same shaft as vertical conveyor are not cost effective. Again, the stacking and reclaiming of pallets falls on the elevator, which is not desirable for fast operations.
U.K. Patent 2,180,827 A deploys a stacker crane and a cumbersome arrangement for the handling and transfer of pallets. The system cannot meet the requirements of a modern parking facility. A stacker crane is obsolete and is not acceptable from the present standpoint of safety.
European Patent 0.505,808 A2, dated Sep. 30, 1992, also suggests complicated two tier lifting arrangements, where the total number of tiers is determined by the hydraulic lift range. There is also a cumbersome transfer mechanism for handling pallets.
Korean Patent 93/08352, dated Apr. 29, 1992, mainly focuses on the pallet handling. The transfer is achieved by a sliding mechanism, which has its own limitations.
In fact none of the prior art patents offer a system which has the characteristics of speed, fault tolerance and low energy consumption required for a modern practical system. In short, handling of over-dimensional platform carriers in large numbers and the peak-hour pressure on the system remain unaddressed. Additionally, redundancy and fault tolerance measures also remain unaddressed. The failings of the prior art are evidenced by the fact that none of the patented technologies have been commercialized, despite heavy demand for a workable solution.
BRIEF SUMMARY OF THE INVENTION
This invention, therefore, is to overcome the drawbacks and disadvantages of the prior art systems and to offer multi level, automated car parking system in which the cars are stored into and retrieved from addressed slots automatically in a simple, practical, safe, speedy, reliable, user-friendly and cost-effective manner, in which cars to be parked are simultaneously received, in which retrieved cars are placed for simultaneous delivery and in which the platform carriers are automatically put into use when required and stack piled when not in use.
The invention is a building structure with plurality of floors, including a plurality of car receiving and delivery floors at the bottom of the building structure and topped with a plurality of parking floors. A car receiving and delivery floor is meant for either receiving cars to be left by customers for parking, or for delivery of cars being retrieved by customers. A car receiving and delivery floor has more floor height than the other floors, and has a plurality of either entry or exit points for cars and for customers. A car receiving and delivery floor also has a storage area, for stacks of “platform carriers” (the platform carriers to be discussed below). A parking floor provides storage space for cars.
Each parking floor has a runway at its center with a fixed track running along the line of parking, and a number of identified and marked storage spaces (hereafter termed as addressed parking slots) on either side of the runway. Each parking tier has one or more transfer modules.
A transfer module is a trolley-like device, with a steel structure frame, wheels, and a separate motor and drive arrangement mounted on it to move it along the fixed track both in forward and reverse direction. The transfer module has two levels: the top level to carry a “platform carrier”, where a platform carrier is pallet-like device for carrying a car, a platform carrier having a steel structure, the platform carrier being fitted with wheels underneath, and the platform carrier having sliding brackets on its edges; and a lower level to accommodate a transfer module power arm, which has a separate drive mechanism and runs in either direction along a fixed second track mounted on the lower level of the transfer module, the fixed second track running transversely to the line of motion of the transfer module. The transfer module power arm is capable, when raised to the height of the top level of the transfer module, of pushing a platform carrier on and off the transfer module.
The transfer module power arm has a transfer module power arm lift, an electrically/hydraulically/pneumatically/magnetically operated lifting arrangement such that the transfer module power arm can be extended to the height of the platform carrier at the upper level of the transfer module in order to push or pull the platform carrier, or retracted to sit at the lower level of the transfer module. With this design, the transfer module power arm can push or pull the platform carrier in either direction. The transfer module power arm is capable of pushing a platform carrier with a car on its top into a parking slot on either side of the transfer module. It is also capable of pulling a platform carrier with a car on its top from a parking slot on either side of the transfer module. When retracted, the transfer module power arm can slide completely underneath the platform carrier from one end of the platform carrier to the other. The transfer module power arm also has an electromagnet at both ends to make and/or break contact with the platform carrier in order to move the platform carrier.
The building structure has one or more elevators oriented along the line of parking. Each elevator is capable of carrying one platform carrier with a car. This elevator is designed to move at a designed speed with load, and move at an increased speed with no load for more time-efficient operation. Each elevator has a fixed third track along the length and has an elevator power arm. The elevator power arm is similar to the transfer module power arm, running along the track in the elevator in either direction, and having its own drive mechanism. The elevator power arm also has an electromagnet at the end facing the elevator “doorway” to make and/or break contact with a platform carrier in order to move the platform carrier in and out of the elevator. The elevator power arm also has tapered protrusions which are supported by mounting brackets of the elevator power arm. The tapered elevator arm protrusions engage with matching receptacles in the side of the platform carrier. The tapered protrusions enable the elevator power arm to still engage with the platform carrier despite minor misalignments between the elevator and the floors of the building structure. The elevator power arm pulls a waiting platform carrier with a car on its top into the elevator, and upon the elevator reaching the desired floor, the elevator power arm pushes the platform carrier with the car on its top out of the elevator. In this manner, a car on top of a platform carrier is moved from a receiving floor to a parking floor. Later, that car is moved in the elevator while on top of a platform carrier from the parking floor to a delivery floor. The elevator power arm facilitates moving a platform carrier with the car on its top in and out of the elevator at the various parking floors. The elevator power arm also facilitates the transfer of a platform carrier with a car on its top between the elevator and the slat conveyors on the car receiving and delivery floors. The elevator power arm pulls the platform carrier with the car on its top from the slat conveyor into the elevator following receiving of a car, and pushes the platform carrier with the car on its top from the elevator onto the slat conveyor during delivery of a car.
On the building's car receiving and delivery floors are “slat conveyors.” A car receiving and delivery floor has a trough at its center running along the line of parking. In that trough is a slat conveyor. The slat conveyor is comprised of slats, which are made of steel plates hinged together to form an endless conveyor. Three slats form a receptacle for a platform carrier. Alternating with the slats on the conveyor are steel grating walkways for drivers to enter and/or exit their vehicles. The car receiving and delivery floor has multiple exit or entry points, each exit or entry point corresponding to a slot for a platform carrier on the slat conveyor. The slat conveyor is driven by drum pulleys on either end, mechanisms for which reside in the storage area in which platform carriers are stored. The slat conveyor is driven by a drive motor, which also resides in the storage area, and the drive motor is capable of driving the conveyor in either direction. A plurality of bearings and support rollers provide support when cars and drivers are on top of the conveyor. A driver drives a car through an entry point onto a waiting, empty platform carrier that is sitting in the slat conveyor. After exiting the vehicle, the driver walks along the adjacent walkway on the slat conveyor and exits the building. When the slat conveyor is filled to its capacity with cars on its carrying side, the slat conveyor moves such that the car is in front of the elevator, at which time the elevator power arm pulls the car to be parked into the elevator.
Further, mounted in the trough along which the slat conveyor runs is a guide rail on either side of the slat conveyor. The sliding brackets of the platform carriers on which the cars are parked engage with these guide rails. The combination of the sliding bracket of the platform carrier engaged with a guide rail provides additional support for the platform carrier with the car parked on top of it while the platform carrier is in a slot of the slat conveyor. The guide rails are not present (are vacated) in the trough in front of the elevator, and at the “transit point” where platform carriers are added and removed from the slot conveyor and moved to and from the storage areas of the car receiving and delivery floors.
The slat conveyor is capable of carrying a platform carrier underneath the slat conveyor. Rollers at either end of the slat conveyor and the sliding bracket/guide rail combination keep the platform carrier engaged with the slat conveyor as the conveyor rotates the slats and steel gratings of the conveyor about the pulley at the end of the slat conveyor.
As described above, a platform carrier is a structure of steel similar to a trolley with wheels designed to carry one car. In prior art, platform carriers are normally of single piece construction. In the present invention, platform carriers are formed by a plurality of plates with hinged construction to facilitate placing and moving along an endless conveyor for automation purposes. The platform carrier also has receptacles at each end to match the tapered protrusions of the elevator power arm to accommodate minor misalignment between the elevator and a floor of the building structure. A platform carrier has electromagnetic components on each end, for engaging the elevator and transfer module power arms so that the platform carrier can be towed or pushed.
As described above, storage areas are present on car receiving and delivery floors, the storage areas to be used for stacks of platform carriers that are not in use. A handling system assigned to each slat conveyor is used for the unused platform carriers, and is comprised of a mono rail, hoisting equipment, and a lifting tackle. The handling system for the platform carriers is used to place platform carriers in stacks in the storage area, or to retrieve a platform carrier from storage and place it on the slat conveyor.
A central system controller manages the automation of the Multi Level Automated Car Parking System. The function of the controller is to coordinate, command, supervise and monitor the operations of all the handling equipment, to display and guide the customers at the main driveway to the building as to which point they should choose for leaving and delivery of their cars, to avoid unproductive back and forth movement of cars and person and strain on the drivers; and to achieve the desired results safely and in time.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The accompanying drawings are intended to provide further understanding of the invention and are incorporated in and constitute a part of the invention. The drawings illustrate an embodiment of the invention and together with the description illustrate the principles of the invention. The drawings should not be taken as implying any necessary limitation or the essential scope of the invention. The drawings are given by way of non limitative example to explain the nature of the invention. For a more complete understanding of the instant invention reference is now made to the following description taken in conjunction with accompanying drawings.
FIG. 1 is the general view of the parking system.
FIG. 2 is the plan view of the basement where retrieved cars are delivered.
FIG. 3 is the plan view of the ground floor where cars are received for parking
FIG. 4 is the plan view of a typical parking floor.
FIG. 5 is the schematic elevation of the facility with slat conveyors and stacked platform carriers in position.
FIG. 6 is the view AA showing the drive end of the slat conveyor.
FIG. 7 is the view BB showing a portion of the slat conveyor.
FIG. 8 is the view CC showing the non-drive end of the slat conveyor.
FIG. 9 a is the plan view of a platform carrier.
FIG. 9 b is the elevation of a platform carrier.
FIG. 10 a is the schematic plan view of the transfer module and a transfer module power arm.
FIG. 10 b is the schematic elevation of the transfer module and a transfer module power arm.
FIG. 11 a is the schematic plan view of the elevator with an elevator power arm.
FIG. 11 b is the schematic elevation of the elevator with an elevator power arm.
FIG. 12 is the isometric view of the handling system for platform carriers.
FIG. 13 is the flow chart for parking.
FIG. 14 is the flow chart for retrieval.
The following are the component identification that is used to refer to the embodiments of the system:
1 . Multi level automatic car parking unit 2 . Basement (delivery station) 3 . Ground Floor (receiving station) 4 . Parking floor 5 . Entry points 6 . Exit points 7 . Parking slots 8 . Transfer module track 9 . Slat conveyor 10 . Walkways 11 . Space for platform carrier 12 . Return drum/drive drum 13 . Drive Motor 14 . Bearings 15 . Support rollers 16 . Guide rails for platform carriers 17 . Transfer module 18 . Transfer module drive 19 . Transfer module Power arm track 20 . Transfer module Power arm 21 . Transfer module Power arm drive 22 . Transfer module Power arm magnetic coupler 23 . Transfer module Power arm lift 24 . Elevator 25 . Elevator power arm track 26 . Elevator power arm 27 . Tapered elevator power arm protrusions 28 . Elevator power arm mounting brackets 29 . Elevator power arm magnetic coupler 30 . Platform carrier 30 a . Platform carrier wheels 31 . Sliding brackets 32 . Platform carrier power arm receptacles 33 . Platform carrier magnetic engagement means 34 . Platform carrier storage area 35 . Mono rail 36 . Hoisting equipment 37 . Lifting tackle 38 . System controller
DETAILED DESCRIPTION OF THE INVENTION
The system will now be described fully with the help of the figures accompanying the invention:
A general view of the parking facility (Part 1 , FIG. 1 ) is shown. It is a typical one, but with one lower floor dedicated for delivery having two slat conveyors, a lower floor dedicated for receiving having two slat conveyors, upper floors for parking, and two elevators. The basement (Part 2 , FIG. 2 ) of the parking facility is dedicated for delivery of the retrieved cars. Arrows in the basement at exit points (Part 6 , FIG. 2 ) show the direction of the movement of retrieved cars. The ground floor (Part 3 , FIG. 3 ) is similarly reserved for receiving cars reporting for parking. Arrows in the ground floor at entry points (Part 5 , FIG. 3 ) show the direction of the movement of cars reporting for parking A typical parking floor (Part 4 , FIG. 4 ) is shown with cars in the parking slots (Part 7 , FIG. 4 ) and a transfer module (Part 17 , FIGS. 4 & 10 a ) with a transfer module power arm (Part 20 , FIGS. 4 & 10 a & b ) on the transfer module track (Part 8 , FIG. 4 ). Two elevators (Part 24 , FIG. 2 , 3 , 4 , 5 ) are positioned with a gap to provide sufficient space to accommodate the return drums (Part 12 , FIG. 8 ) of the two slat conveyors (Part 9 , FIG. 2 , 3 , 5 ) in line and also provide storage space (Part 34 , FIG. 5 , 12 ) for the platform carriers (Part 30 , FIG. 9 , 4 ). Each elevator has an elevator power arm (Part 26 , FIGS. 11 a & b ). This elevator power arm has its own drive mechanism and moves in both directions along a fixed track (Part 25 , FIG. 11 a ) inside the elevator. The elevator power arm has two elevator power arm protrusions (Part 27 , FIG. 11 b ) mounted on elevator power arm mounting brackets (Part 28 , FIG. 11 b ) to accommodate minor mismatches in alignment between the elevator and the floors of the structure. The elevator power arm has an elevator power arm magnetic coupler (Part 29 , FIG. 11 a ) to impart movement to a platform carrier.
A transfer module (Part 17 , FIGS. 4 , 10 a & b ) is a structural assembly unit with its own independent transfer module drive (Part 18 , FIG. 10 a ) designed to move the transfer module in either direction along the transfer module track. This transfer module runs along a transfer module track (Part 8 , FIG. 4 ) parallel to the parking slots (Part 7 , FIG. 4 ) in each parking floor (Part 4 , FIG. 4 ). A transfer module power arm track (Part 19 , FIG. 10 a , 4 ) on the transfer module guides the movement of the transfer module power arm (Part 20 , FIGS. 10 a & b ) transversely to the movement of the transfer module (Part 17 , FIG. 4 , 10 a ). This transfer module power arm has its own transfer module power arm drive (Part 21 , FIG. 10 a ) and moves in both directions along the power arm track fixedly mounted to the transfer module. This transfer module power arm also has a transfer module power arm lift to permit the movement of the transfer module power arm underneath the platform carrier and the car, if necessary, and to position the transfer module power arm magnetic coupler (Part 22 , FIG. 10 b ) to push/tow the platform carrier in either direction.
The slat conveyors (Part 9 , FIG. 2 , 3 ) are driven by motors (Part 13 , FIG. 6 ) and drive drum pulleys (Part 12 , FIG. 6 , 8 ). The drive and return drums are supported by thrust bearings (Part 14 , FIG. 6 ). Walkways (Part 10 , FIG. 2 , 3 ) are permanently fixed on the top of the slat conveyors (Part 9 , FIG. 2 , 3 ) with space (Part 11 , FIG. 2 , 3 ) to accommodate platform carriers (Part 30 , FIG. 9 ) between two adjacent walkways. Guide rails (Part 16 , FIG. 7 ) run on the track along the slat conveyor to guide the movement of platform carriers (Part 30 , FIG. 9 ). Construction of platform carriers is shown in FIG. 9 . The platform carriers are comprised of plates which are joined by hinged joints. The platform carriers have sliding brackets on the exterior edges of the platform carriers (Part 31 , FIGS. 9 a & b ), the sliding brackets designed to engage the guide rails along the slat conveyor. The platform carriers have tapered receptacles that engage with the tapered protrusions of the elevator arm (Part 32 , FIG. 9 a ). The platform carriers have four wheels disposed on the surface opposite the surface on which the car rests (Part 30 a , FIGS. 9 a & b ). The platform carriers have a platform carrier magnetic coupler on opposite ends of the platform carrier (Part 33 , FIG. 9 a ), the magnetic couplers designed to engage with magnetic couplers on the elevator power arm (Part 29 , FIG. 11 a ) and the transfer module power arm (Part 22 , FIGS. 10 a & b ).
Support rollers (Part 15 , FIG. 7 ) are provided to prevent sagging due to weight and due to hinged construction. Safety interlocks and guards ensure highest safety to clients and cars.
Four sets of handling systems comprising mono rail (Part 35 , FIG. 12 ), hoisting equipments (Part 36 , FIG. 12 ) and designed lifting tackles (Part 37 , FIG. 12 ), two in basement and two at ground level, are provided.
All these embodiments of the system, viz, elevators, power arms in the elevators, slat conveyors, transfer modules, transfer module power arms and the handling equipments, are programmed controlled and monitored to work in tandem with each other to ensure continuous parking and retrieval operations by the system controller (Part 38 , FIG. 13 , 14 ).
The Operation of the System:
The uniqueness of this invention lies in its easy adaptability to meet changing patterns in parking/retrieval demands. The operations of the system, under normal and peak hour conditions, are described below:
Normal Conditions:
Parking: Normal conditions apply when cars reporting for parking more or less match the retrieval requests. As a car reports at the reception, the system controller acknowledges receipt of the car, checks availability and allots a platform carrier and displays and directs the client to the entry point at the ground level. The client following the instructions drives the car onto the allotted platform carrier, parks, applies hand brakes, alights, locks the car and walks away along the walkway. This is repeated until the slat conveyor is full. When one slat conveyor is full, the system controller recognizes and directs the further reporting car to the other vacant slat conveyor. Obeying command from the system controller, the elevator power arm, moving on the elevator power arm track, draws the platform carrier with the car immediately in front of it into the elevator. The elevator raises the car to a parking floor. On reaching the floor, the elevator power arm, similarly moving on the elevator power arm track, pushes the platform carrier with the car onto the waiting transfer module which was commanded to wait in place by the controller. The transfer module, moving on the transfer module track of the parking floor, carries the platform carrier with the car in front of the designated slot. On reaching the destination, the transfer module power arm positions itself to the right place. The transfer module power arm lift operates, and the magnetic coupling of the transfer module power arm engages with the magnetic coupling of the platform carrier. The transfer module power arm moves along the transfer module power arm track towards the allotted slot, pushing the platform carrier with the car into the allotted slot. The transfer module power arm after placing the car in the slot disengages the magnetic couplings and returns to its retracted position on the transfer module. The slat conveyor moves forward to place the next platform carrier with the car in front of the elevator to continue the parking operations till all the remaining platform carriers with cars are cleared from the slat conveyor. Such receiving and parking operations are alternated between the two slat conveyors on the ground floor. The whole thing is represented by a Flow Sheet ( FIG. 13 ) for clarity.
Retrieval: When a request for retrieval reaches the system controller, the system controller directs the transfer module in the specific parking floor to move along the transfer module track to reach the parking slot where the requested car is parked. On reaching, the transfer module power arm positions itself to the right place, operates the transfer module power arm lift, engages the transfer module power arm magnetic coupler with the platform carrier magnetic coupler, and moves along the transfer module power arm track in the transfer module towing the platform carrier with the particular car onto the transfer module. The transfer module, moving on the transfer module track, carries the platform carrier with the car to the waiting elevator and disengages the magnetic couplings. The elevator power arm, moving on the elevator power arm track, engages its magnetic coupling to the magnetic coupling of the platform carrier and draws the platform carrier with the car into the elevator and the elevator descends to the delivery floor. On reaching the delivery floor, the elevator power arm pushes the platform carrier with the car onto the vacant space in the slat conveyor immediately in front of the elevator and disengages the magnetic couplings. The slat conveyor moves forward to place the retrieved car to the delivery point and to simultaneously position the next vacant space in the slat conveyor to continue the retrieval operations till retrieved cars occupy all the vacant spaces in the slat conveyor. The client, informed by a main system display of the location of the client's car, walks up to his car and drives away. Such delivery and retrieval operations are alternated between the two slat conveyors in the basement. The whole thing is represented by a Flow Sheet ( FIG. 14 ) for clarity.
Peak Hour Conditions:
Parking: At the start of the day, the demand for parking is at its peak. To cope with the situation, the system controller presses one or both of the slat conveyors in the delivery section into parking operations till the situation normalizes. The system controller takes additional care to coordinate among the slat conveyors for proper execution. By this arrangement, the capacity to handle parking requests is doubled.
Retrieval: Likewise, at the close of the day, the demand for retrieval is at its peak. To cope with the situation, the system controller presses one or both of the slat conveyors in the receiving section into retrieval operations till the situation normalizes. The system controller takes additional care to coordinate among the slat conveyors for proper execution. By this arrangement, the capacity to handle retrieval requests is doubled.
Handling (storage): Once the system controller recognizes full occupancy of the spaces by empty platform carriers in the delivery section of any slat conveyor, the system controller commands the handling system to come into operation. The handling arrangement picks up the platform carrier immediately below its loading point, carries along the mono rail and stacks alternately in two rows. The slat conveyor moves forward to bring the next platform carrier to be stored into the loading point. This operation continues till all the platform carriers in the slat conveyors are stacked.
Handling (Loading): Once the system controller recognizes full vacancy of the space in the receiving section of any slat conveyor, the system controller commands the handling system to come into operation. The handling arrangement picks up the platform carrier alternately from two storage rows, carries along the monorail and places on the slat conveyor in the vacant space immediately below the loading point. After receiving the platform carrier, the slat conveyor moves forward to bring the next vacant space into loading point for receiving next platform carrier. This operation continues till all the vacant spaces in the slat conveyor are loaded with platform carriers. | A structure having floors for receiving and delivery of cars, and parking floors. Receiving and delivery floors have slat conveyors with platform carriers placed in slots in the conveyor. Cars are parked by patrons on the platform carriers. After the patron exits the car the conveyor conveys the carrier on which the car is parked to the front of an elevator. A power arm in the elevator draws the carrier into the elevator, and the elevator rises to a parking floor. On the parking floor the elevator power arm pushes the platform carrier with the car on top onto a waiting transfer module, which moves laterally to the front of an allotted parking slot. A power arm on the transfer module pushes the platform carrier with the car on top into the parking slot. Upon the patron's return the car is retrieved as described above but in reverse order. | 4 |
CROSS-REFERENCE
This is a continuation of application Ser. No. 171,976, filed July 24, 1980, now U.S. Pat. No. 4,357,728 issued Nov. 9, 1982.
INTRODUCTION
The present invention generally relates to containers for the collection of refuse, trash, leaves and the like. More particularly, the present invention relates to such containers which employ conventional disposable plastic trash bags and are intended for household application by the general consuming public.
BACKGROUND OF THE INVENTION
Any number of containers, collectors and transporters for refuse such as garbage, leaves, grass clippings and the like have been suggested and commercialized in the past. These range from commercial units weighing hundreds of pounds and requiring special transport trucks, to widely marketed inexpensive consumer oriented products. The generally available commercial units typically prove to be unacceptable for household applications due to size and, more importantly, weight and cost considerations. Containers which are structurally sounds, versatile and convenient to use are generally cost ineffective for household type applications. Additionally, units designed for commercial application are often unsatisfactory for household use inasmuch as they are structurally complex and may be hazardous to an untrained user.
Refuse containers for noncommerical or household applications which are inexpensive and relatively easy to employ abound. However, such prior art containers often have a number of shortcomings. Many containers which have received consumer acceptance attribute success only to mass marketing such as through television and newspaper advertising rather than through engineering and design excellence. Such containers often are not well engineered and employ inferior or substandard materials. Additionally, such consumer oriented prior art containers are often intended for only a single light duty application such as collecting leaves and are totally unacceptable for others such as receiving relatively heavy grass clippings either from thatching or mowing the lawn. A consumer is often tempted to use the container for other nonintended applications, causing it to break outright or substantially lessen its useful life. Finally, single application containers often are not adjustable to accommodate disposable trash bags of varying dimensions and volumes.
Many refuse containers intended for home use, although inexpensive, are extremely difficult to use and result in a net loss of efficiency. For example, prior art frames for use in distending conventional disposable plastic garbage bags or the like are made up of a number of separate wire members which must be assembled and locked into position each time the container is to be used or repositioned. In addition to being awkward, such containers, by virtue of their many separate parts tend to be rendered useless through loss of one or more of the parts. Additionally, such devices can be hazardous inasmuch as the members are often pivotally mounted to one another and may have sharp edges resulting in finger catching "scissor-type" action as they are being deployed or disassembled.
An additional problem common to consumer type refuse containers is their lack of mobility both during and after collection of refuse. Prior art designs are often unstable unless they are staked into the ground. Such devices inherently require uprooting each time the user desires to move it from one location to another in the process of collecting refuse. This can be extremely difficult in applications such as raking leaves wherein relatively frequent repositioning of the container is required. An additional shortcoming of such a device is its stability in only a single orientation i.e. the collection, position, but not in the transporting position. This problem is particularly aggravated in situations when the container is full or nearly full of relatively heavy refuse. A related problem is that the bag is not fully supported in the transporting position and thus is susceptible to becoming detached from the frame or being ripped and thereby spilling the contents.
Finally, many prior art devices fail to provide versatility for the aged or physically infirm wherein the design allows the user to apply mechanical advantage thereto in repositioning it from the refuse collecting position to the transporting position. Most prior art devices require that the user bear the full weight of the container as well as its contents.
Representative of the best prior art are U.S. Pat. Nos. 3,106,303 to Finocchiaro, 3,170,183 to Leatherman, 3,697,030 to Schultz, 3,934,803 to Paulus, Jr., and 4,006,928 to Beugin. The devices disclosed in these patents, although being useful in their specific intended applications, are chosen to collectively represent some of the above discussed shortcomings of the prior art as a whole.
U.S. Pat. No. 3,170,183 discloses a one piece dust pan and basket combination which is constructed of plastic to provide a sweeping kit which enables dirt or the like to be swept directly into a retention receptacle without the use of an additional dust pan. Two slots are provided in the receptacle which act as a hand grip for carrying the receptacle while in the dirt collecting position. The waste basket can be positioned upright for retaining refuse or tipped over on its side for receiving the dirt.
U.S. Pat. Nos. 3,934,803, 3,697,030 and 4,006,928 disclose frame-type refuse collectors which distend and coact with a collapsible garbage bag and permit sweeping of refuse directly into the mouth of the bag which is held open by the frame.
U.S. Pat. No. 3,106,303 disclose a collapsible cart for collecting relatively light and bulky refuse and allows transporting thereof through supportive wheels.
BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a portable dust pan and refuse container combination which overcomes the above described shortcomings of the prior art by providing a highly portable, stable, yet inexpensive and lightweight container which employs an open mouthed, elongated flexible collection bag which is easily installed with and removed from the rest of the container. According to the present invention, the dust pan and refuse container combination includes a bag supporting frame which distends and substantially encloses the bag, means which holds the mouth of the bag rigidly open for receiving refuse, two or more spaced, ground contacting wheels which are rotatably mounted to the frame of a common axis to permit selective rotational repositioning of the frame of a common axis to permit selective rotational repositioning of the frame about the axis from a first, substantially vertical refuse transporting position, to a second, substantially horizontal refuse collecting position and, finally, a dust pan which depends from the frame adjacent the mouth of the bag and projects angularly outwardly therefrom with respect to the line of elongation of the bag and which operates to abut the ground when the container is in the second position. This arrangement has the advantage of providing an inexpensive yet extremely strong, stable and highly mobile refuse collector and container which is very efficient and convenient to use in the collection of refuse while requiring a minimum of physical exertion both in transporting the container from a storage area such as the garage to the area of use such as the lawn and in transitioning the container between the first and second positions and back to the first position when the container is full of refuse.
According to the preferred embodiment of the invention, a handle is provided integrally with the frame which depends substantially outwardly therefrom both in the first and second positions. This arrangement has the advantage of allowing the user to readily grasp and reposition the container either from the sides or while addressing the container from the end holding the mouth of the bag. Additionally, this same handle facilitates pushing the container once fully loaded to an area for dumping of the refuse or removal of the bag from the frame.
According to another aspect of the invention, an additional pair of wheels are provided which are rotationally mounted on the frame on a second axis which is parallel to but spaced from the common axis and operative to coact with the first pair of wheels to support the container when in the first or upright position. This arrangement has the advantage of providing a container whose weight is fully supported on wheels when in the upright position.
According to another aspect of the present invention, first and second opposed side guard members are provided which depend angularly outwardly from the frame and coact with the dust pan to define a converging refuse guiding entrance to the mouth. This arrangement has the advantage of providing efficient acceptance of refuse from a direction angularly offset with the line of elongation of the bag and prevents spillage from around the mouth of the bag.
According to another aspect of the invention, the dust pan and refuse container is collapsible and adjustable to accommodate trash bags of varying dimensions and capacities. This arrangement has the advantage of providing a convenient, flexible container which collapses to minimize storage volume requirements by employing constituent elements (structural members) which operatively (pivotally) engage one-another.
According to still another aspect of the invention, the dust pan projects outwardly further than the side guard members mentioned herein above and includes a ground embracing edge at the outer terminus thereof. This extended portion acts as a cantilever as it bears against the ground thereby preventing refuse from escaping underneath the edge when a refuse collecting instrument such as a rake is passed toward the mouth of the bag and otherwise may catch the underside of the ground embracing edge.
These and other features and advantages of this invention will become apparent upon reading the following specification, which, along with the patent drawings, describes and discloses a preferred illustrative embodiment and an alternative embodiment of the invention in detail.
The detailed description of the specific embodiment makes reference to the accompanying drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 is a perspective view of the preferred embodiment of the inventive dust pan and refuse container illustrated in its first or refuse collecting position;
FIG. 2 is a side plan view of the dust pan and refuse container of FIG. 1 illustrating the container in its first or upright position (solid line) and in its second or refuse collection position (dotted line);
FIG. 3 is a fragmented cross-sectional view of the dust pan and refuse container of FIG. 1 shown on an enlarged scale; and
FIG. 4 is a side plan view of an alternative embodiment of the inventive dust pan and refuse container in an enlarged scale.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to drawings FIGS. 1 through 3, a preferred embodiment of a combination dust pan and refuse container 10 (hereinafter referred to as container) is illustrated. Although the container 10 is principally intended for consumer or household type applications, it is contemplated that it could also be employed for many commercial or industrial applications. The specific use for the container 10 contemplated by the applicant is an aid in gathering, transporting and storing refuse or items which are scattered on the ground such as grass clippings, thatch, dust, dirt, leaves and the like.
The container 10 includes a bag supporting frame 12 made up of four substantially parallel spaced elongated members 14a, 14b, 14c, and 14d. The parallel spaced elongated members 14a through 14d collectively define the edges of a refuse bag nesting area 16. The parallel spaced elongated members 14c and 14d are interconnected by a rigidly fixed axle 18 which projects laterally outwardly therefrom in both directions to rotatably support a first pair of ground contacting wheels 20. Although only one wheel 20 is illustrated, it is to be understood that the container 10 is substantially symmetrical and a second wheel 20 (not illustrated) is rotatably mounted on the opposite end of the axle 18. The axle 18 defines a first rotational axis designated A. Likewise, the parallel spaced elongated members 14a and 14b are interconnected by a second axle 22 which is affixed therebetween and extends laterally therebeyond to rotatably support a second pair of ground contacting wheels 24. The axles 18 and 22 therefore act as structural members which maintain the spaced parallel elongated members 14a through 14d in their illustrated laterally fixed spaced relationship.
Longitudinal (between wheels 20 and 24) structural support is provided by a bottom bag supporting frame 26 which is interconnected between the axles 18 and 22 and is constructed from a wire mesh having a number of parallel lateral members 28 and a number of parallel longitudinal members 30 at right angles to the parallel lateral members 28 and welded thereto to form a mesh or grate which is rigidly affixed to the remainder of the frame 12. The axle 22 defines a second axis B which is substantially parallel to and spaced from the axis A.
When the container 10 is in its upright or first position as illustrated in FIG. 3, the wheels 20 and 24 will all be contacting the ground designated 31 to provide a stable support therefor and permit a high degree of mobility by virtue of the rotational mounting of the wheels 20 and 24 upon the axles 18 and 22.
Lateral structural support of the container 10 is also supplied by an upper bag supporting frame 32 which, like the bottom bag supporting frame 26 is a mesh formed of a number of parallel lateral members 34 affixed normally to a number of substantially parallel vertical members 36. The lateral members 34 are fixedly spaced between the spaced parallel elongated members 14a and 14b of the frame 12. A lower bag supporting frame 38 is substantially identical to the upper bag supporting frame 32, including a number of parallel lateral members 40 interconnecting the spaced parallel elongated members 14c and 14d of the frame 12 normally affixed to a number of vertical members (not illustrated). The vertical members of the lower bag supporting frame 38 are singularly integrally formed with the associated longitudinal members 30 of the bottom bag supporting frame 26 and the parallel vertical members 36 of the upper bag supporting frame 32, i.e. each associated set of longitudinal members (30, 36 and not shown) are formed from a single "C" shaped length of wire.
Referring specifically to FIG. 3, the upper ends of the spaced parallel elongated members 14a and 14b are integrally interconnected by a handle 42 which extends upwardly and rightwardly therefrom. Spacing of the spaced parallel elongated members 14a and 14b is maintained at their ends opposite the wheels 20 and 24 by a bag supporting chute 44 which is constructed of a first pair of spaced angled members 44a and 44b and a second pair of angled members 44c and 44d. The spaced angled member 44a interconnects the upper ends of the spaced parallel elongated members 14b and 14c of the frame 12, the spaced angled member 44b interconnects the spaced parallel elongated members 14a and 14d of the frame 12, the spaced angled member 44c interconnects the spaced parallel elongated members 14a and 14b of the frame 12 and the spaced angled member 44d interconnects the spaced parallel elongated members 14c and 14d of the frame 12. The spaced angled members 44a, 44b, 44c, and 44d collectively define a converging refuse inlet aperture generally designated 46. Additional structural support is provided by a wooden cross member 48 which interconnects the spaced parallel elongated members 14a and 14b of the frame 12 adjacent the point at which the spaced parallel elongated members 14a and 14b transition into the handle 42.
The spaced angled member 44d of the bag supporting chute 44 extends upwardly and leftwardly substantially further than the other members. This extension is defined for the purposes of the present application as a dust pan 50. The dust pan 50 includes a lower portion 50a which transitions with the spaced angled member 44d of the bag supporting chute 44 and has a relatively uniform cross section. The dust pan 50 also includes an upper portion 50b which projects upwardly from the lower portion 50a and has a transitioning cross-sectional area which terminates in a relatively sharp ground embracing edge 50c. In application, the dust pan 50 operates as a cantilever as will be described in detail herein below.
The upper terminus of the spaced parallel elongated members 14c and 14d of the frame 12 are closed by cup shaped plastic caps 52a or the like. The lower most portion of the bag supporting chute 44 extends downwardly defining an extension 44e, the outer circumference of which includes a bag supporting surface 44f. The lower terminus of the bag supporting chute 44 is of increased wall thickness as designated at 44g. An open mouthed, elongated flexible collection bag 52 is disposed within the bag nesting area 16 and has its mouth rigidly held open by the insertion therein of the extension 44e of the bag supporting chute 44. An elastic band 54 passes around the bag 52 near the mouth thereof and embracingly holds the bag 52 against the surface 44f of the bag supporting chute 44. This arrangement causes the bag 52 to be partially distended and contained within the bag nesting area by the influence of the enclosing or surrounding frame 12. In the first or upright position, the bag nesting area 16 is closed on the front (adjacent the dust pan 50) and the back (adjacent the handle 42) sides as well as the bottom by the lower bag supporting frame 38, the upper bag supporting frame 32 and the bottom bag supporting frame 26, respectively. Although the lateral sides of the frame 12 are open, the bag 52 is prevented from escaping therethrough by a pair of bag restraining straps 56. The straps 56 are provided with buckles 58 whereby tension in the straps 56 can be released and the bag 52 removed laterally from the bag nesting area 16 once the elastic band 54 has been released from the mouth area of the bag 52.
Operation of the container 10 can best be understood by referring to FIG. 2 which illustrates the container 10 both in its first or upright substantially vertical refuse transporting position (in solid line) and also in its second, substantially horizontal refuse collecting position (in dotted line). In transporting the container 10, the user walks therebehind and grasps the handle 42, pushing or pulling same. When the container 10 is positioned near refuse that is to be collected, it is then rotated from the first position to the second position about axis A whereby the wheels 24 are rotated counterclockwise to assume a position substantially above the wheels 20. The ground embracing edge 50c of the dust pan 50 will contact the ground 31 and will firmly bear there against by virtue of its cantilever design. It has been found that the upper portion 50b will bend slightly at a point indicated by arrow 60 causing a spring action or preload of the dust pan 50 as it bears against the ground 31 to prevent refuse being collected from escaping therebetween. It should be noted that the handle 42 is designed in such a way as to project upwardly, both in the first and second positions of the container 10, and thereby facilitates movement of the container 10 and transitioning thereof between the positions. Additionally, when all of the refuse in the immediate area has been collected but more remains at a distance, rather than returning the container 10 to the first position, it is contemplated that the handle 42 can be grasped and rotated clockwise upwardly just enough to relieve the preload on the dust pan 50 and then move the container 10 to the new position for collecting additional refuse. This procedure is not recommended for moving the container 10 great distances but only for moving, for example, from one location to another nearby location.
Because of the elongated design of the frame 12, the center of gravity (designated cg) of the combined container 10 and refuse contained therein will be substantially nearer axis A than is the handle 42. As is apparent to one of ordinary mechanical skill and intuition, the handle 42 will provide a substantial mechanical advantage in repositioning the container 10 from the second position back to the first position. Thus, the aged or physically infirmed can employ the container 10 with very little effort. When the bag 52 is full, it is removed by loosening the strap 56 at the buckle 58 and sliding the mouth portion of the bag 52 downwardly away from the bag supporting chute 44 while the elastic band 54 has been stretched radially outwardly. The mouht of the bag 52 can then be closed by conventional ties or other methods and the filled, closed bag can be removed from the bag nesting area 16 by sliding it laterally out of the frame 12.
Referring to FIG. 4, an alternative embodiment of a combination dust pan and refuse container 70 (hereinafter referred to as container) is illustrated. Like the container 10 illustrated in FIGS. 1 through 3, the container 70 is principally intended for consumer or household type applications. The operation of the container 70 is, therefore, identical to that described herein above with a few exceptions as will be described hereinbelow. All of the claimed inventive features can be equally applied to both the preferred embodiment and the alternative embodiment of the invention. Several of the inventive features are described and illustrated in detail only in one of the embodiments of the invention, it being understood that such features are equally applicable to the other embodiment as will be obvious to one of ordinary skill in the art in view of the present specification.
The container 70 includes a bag supporting frame 72 and a conventional compliant, disposable trash or garbage bag. The frame 72 includes substantially parallel laterally spaced elongated members 74, the lower terminus of which are rigidly affixed to a laterally oriented stub axle shaft 76 which retains the parallel laterally spaced elongated members 74 in the illustrated laterally spaced relationship. It should be noted that a reverse plan view of the alternative embodiment of the invention illustrated in FIG. 4 is the exact compliment of FIG. 4 and thus has been omitted for the sake of brevity.
The stub axle shaft 76 extends laterally outwardly beyond the parallel laterally spaced elongated members 74 and rotatably supports the rear (right-hand most) ends of a pair of longitudinally oriented elongated members 80 as well as a pair of ground contacting wheels 78 which are free to rotate about the stub axle shaft 76 but are prevented from axial displacement therealong by entrapment between the parallel laterally spaced elongated member 74 and suitable fastener means at each end of the stub axle shaft 76 such as threaded nuts, cotter pins, swedging or the like. The longitudinally oriented elongated members 80 are of substantially the same extent as are the parallel laterally spaced elongated members 74. A second stub axle shaft 82 passes through aligned apertures in the left-hand most ends of the longitudinally oriented elongated members 80. Like the stub axle shaft 76, the second stub axle shaft 82 projects laterally outwardly beyond the longitudinally oriented elongated members 80 and rotatably supports a second pair of ground contacting wheels 84 between the means and the longitudinally oriented elongated members 80 to prevent axial displacement of the wheels 84 along the second stub axle shaft 82.
The second stub axle shaft 82 passes through a laterally aligned bore within the lower portion of a front bag supporting access door 86, the lateral extent of which interspaces the longitudinally oriented elongated members 80. The access door 86, which is constructed of wood, is free to rotate thereabout unless otherwise restrained. Near the uppermost extent of the lateral surfaces of the access door 86 are a pair of opposed axially aligned thumb screws 88. A knob 90 is affixed to the left-hand most surface of the access door 86. The access door 86 is retained in the illustrated position (solid line) by a pair of longitudinally extending support members 92 which are substantially parallel to one another as well as the longitudinally oriented elongated members 80. The right-hand ends of the longitudinally extending support members 92 are rotatably secured to the parallel laterally spaced elongated member 74 by screws 94 or the like. The left-hand ends of the longitudinally extending support members 92 have downwardly opening notches 96 which, in the assembled (solid line) position cause the left-hand ends of the longitudinally extending support members 92 to be embracingly secured between the access door 86 and the thumb screws 88.
A pair of diagonally oriented members 98 provide rigidity to the bag supporting frame 72. Each diagonally oriented member 98 is articulated by an over center snap acting hinge 100, the structure and operation of which is well known in the art and will not be elaborated upon here. One end of each diagonally oriented member 98 is affixed to its associated parallel laterally spaced elongated member 74 by a screw 102 at a point intermediate the stub axle shaft 76 and the screw 94. The other end of each diagonally oriented member 98 is attached to its associated longitudinally oriented elongated member 80 by means of a screw 104 at a point intermediate the stub axle shafts 76 and 82, respectively.
In their illustrated position, the diagonally oriented members 98 rigidly support the parallel laterally spaced elongated members 74 and the longitudinally oriented elongated members 80 in their illustrated positions. When the longitudinally extending support members 92 are clamped to the access door 86 by the thumb screws 88, the entire assembly is rigid. The longitudinally oriented elongated members 80, the longitudinally extending support members 92 and the diagonally oriented members 98 are constructed of aluminum bar stock having a rectangular cross section. The function of this particular arrangement is described in detail herein below in the description of operation of the alternative embodiment of the invention.
A bottom bag supporting frame (not illustrated) defines a horizontally planar bottom to the supporting frame 72 and is supported by and traverses the lateral space between the longitudinally oriented elongated members 80. The actual structure of the bottom bag supporting frame is substantially indentical to the frame 26 described herein above and illustrated in FIGS. 1 and 2. Likewise, a vertically oriented, planar upper bag supporting frame (not illustrated) is also provided which is supported by and is interspaced between the parallel laterally spaced elongated members 74. The upper bag supporting frame is substantially identical in structure and function to the upper bag supporting frame 32 described herein above and illustrated in FIG. 1. Detailed description of the structure of the frames is deleted here to avoid duplication.
The parallel laterally spaced elongated members 74 are constructed of tubular metal such as aluminum and openly terminate upwardly to telescopingly receive a pair of upper vertical members 106 which are integrally formed from a single piece of slightly smaller aluminum tubing in a generally inverted U-shape configuration, the upper terminus of which defines a handle 108 which extends upwardly and rightwardly therefrom. A thumb screw clamp 110 is provided in the upper terminus of each parallel laterally spaced elongated member 74 which can be tightened to cause the upper portion of the parallel laterally spaced elongated member 74 to snuggly embrace the lower portion of the upper vertical member 106 nested therein. Added structural support is provided by a wooden cross member 112 which interconnects the upper portion of the upper vertical members 106 of the supporting frame 72 and is secured thereto by fastener means such as screws (not illustrated).
The wooden cross member 112 supports a converging refuse inlet aperture, generally designated 114, which is defined by nestingly engaged front and rear bag supporting members 116 and 118, respectively. The front and rear bag supporting members 116 and 118 are opposed and generally "U" shaped in horizontal cross section, the free legs of which slidably engage one another to define the inlet aperture 114. A pair of opposed axially aligndd thumb screws 120 threadably engage the legs of the front bag supporting member 116, passing laterally outwardly through elongated slots 122 in the legs of the rear bag supporting member 118. When the thumb screws 120 are tightened, they cause the legs of the rear bag supporting member 118 to be trapped between the thumb screws 120 and the legs of the front bag supporting member 116.
The lower terminus of the front and rear bag supporting members 116 and 118 are of increased wall thickness as designated at 116a and 118a, respectively. An open mouthed, elongated collection bag (illustrated fragmentarily) 124 is disposed within a refuse bag receiving area, generally designated 126, which extends downwardly to the uppermost surface of the bottom bag supporting frame. The elongated collection bag 124 has its mouth rigidly held open by a lower terminus of the combined front and rear bag supporting members 116 and 118. A number of spring acting clips 128 are externally peripherally spaced about and have one end affixed to the front and rear bag supporting members 116 and 118, and depend downwardly from their attachment point in cantilever fashion. The free ends of the clips 128 are biased against the front and rear bag supporting members 116 and 118 to collectively form a bag clamping mechanism therewith. The elongated collection bag 124 is held in the illustrated position by passing the open end thereof upwardly between the spring clips 128 and the portions of the front and rear bag supporting members 116 and 118 adjacently associated therewith.
The front bag supporting member 116 extends upwardly and leftwardly substantially further than the rear bag supporting member 118. This extension is defined for the purposes of the present application as a dust pan 130. The dust pan 130 defines a refuse guiding ramp 130a (illustrated in a locally broken away section) which, when the dust pan and refuse container 70 is in the trash collecting position, guides refuse into the inlet aperture 114. Laterally spaced, longitudinally oriented left and right dust pan support webs 130L and 130R are provided to structurally reinforce the dust pan 130 as well as provide lateral refuse guidance.
The alternative embodiment of the invention, as illustrated in FIG. 4, operates as follows. The dust pan and refuse container 70 is adjustable both in vertical height as well as the area of the refuse inlet aperture 114 to accommodate elongated collection bags 124 of varying dimensions and capacities. The area of the refuse inlet aperture 114 is adjustable by loosening the thumb screws 120 and slidingly repositioning the rear bag supporting member 118 forwardly or rearwardly to assume a combined (with member 116) outer circumferential dimension which is slightly less than the mouth or opening of the elongated collection bag 124. Subsequent retightening of the thumb screws 120 assures that the new area of the inlet aperture 114 will remain the same. Note that only the rear bag supporting member 118 is displaceable with respect to the supporting frame 72. The front bag supporting member 116 is affixed to the supporting frame 72 (specifically to cross member 112) by a bridge supporting member 132 by fastening means such as screws (not illustrated). Thus, the front bag supporting member 116 is at all times maintained in the fixed orientation illustrated with respect to the upper vertical members 106.
Variations in the capacity or height of the elongated collection bag 124 can be accommodated by attaching the elongated collection bag 124 to the front and rear bag supporting members 116 and 118 via the spring clips 128, loosening the thumb screw clamp 110 and sliding the upper vertical members 106 downwardly into the parallel laterally spaced elongated members 74 until the lower most extent of the elongated collection bag 124 abuts the upper most surface of the bottom bag supporting frame. At this point, the thumb screw clamp 110 is retightened and the refuse container 70 is ready for use. The elongated collection bag is contained within the elongated collection bag receiving area 126 by the bottom and upper bag supporting frames, the access door 86, the longitudinally extending support members 92, the diagonally oriented members 98, and a pair of laterally spaced upstanding planar guide members 134 which depend from the longitudinally oriented elongated members 80. The planar guide members 134 are substantially trapezoidal in shape and are spaced substantially to the same extent as are the longitudinally oriented elongated members 80.
Once the elongated collection bag 124 is filled and the operator desires to remove it from the container 70, the thumb screws 88 are loosened, the longitudinally extending support members 92 are rotated clockwise to assume a substantially vertical orientation (as is illustrated in phantom and arrow designated 136), and the access door 86 is rotated counterclockwise to assume a substantially horizontal orientation (as is illustrated in phantom and arrow designated 138). Note that the longitudinally extending support members 92 and the access door 86 are illustrated in phantom in intermediate positions (during the process of respositioning). With the longitudinally extending support members 92 temporarily in the substantially vertical position and the access door 86 in the substantially horizontal position, the elongated collection bag 124 is freely accessible to the user from the front (left as illustrated in FIG. 4) of the refuse container 70 and can be simply removed by pulling the upper or mouth portion of the elongated collection bag 124 downwardly, disengaging it from the spring action clips 128 and over the area of increased wall thickness 116a and 118a of the front and rear bag supporting members 116 and 118, respectively. The elongated collection bag 124 can then can be tied closed if desired and freely removed forwardly from the supporting frame 72.
When fully assembled and including an elongated collection bag 124, the dust pan and refuse container 70 is employed substantially as described in the detailed description herein above relating to FIGS. 1 through 3 and a discussion thereof is deleted here to avoid duplication. The axis of the stub axle shaft 76 should be considered as equivalent to the second rotational axis B and the axis of the second stub axle shaft 82 should be deemed to be the first rotational axis designated A.
The dust pan and refuse container 70 is collapsible to minimize its space or volume requirements during storage thereof. Collapsing of the container 70 is accomplished as follows. Starting with the container 70 assembled as illustrated in solid line in FIG. 4, the thumb screws 88 are loosened slightly. The thumb screw clamp 110 is loosened and the handle 108 is lowered into the parallel laterally spaced elongated members 74, i.e. when the uppermost terminus of the parallel laterally spaced elongated members 74 abut the lowermost surface of the cross member 112. The thumb screw clamp 110 is then retightened. The user than grasps the diagonally oriented members 98 adjacent the hinge 100 and pulls upwardly and leftwardly, as illustrated in FIG. 4, to disengage the over center snap acting hinge 100 whereby the portion of the diagonally oriented member 98 on either side of the hinge 100 will become skewed with respect to one another. The screws 94, 102 and 104 are tight enough to prevent lateral displacement of the longitudinally extending support and diagonally oriented members 92 and 98, respectively, but allow their rotational displacement if not otherwise prevented. As the hinge 100 is repositioned upwardly and leftwardly, the entire assembly of the longitudinally oriented elongated and longitudinally extending support members 80 and 92, the second stub axle shaft 82, the ground contacting wheels 84, the access door 86 and the planar guide members 134 will rotate generally clockwise in a scissors fashion as will now be apparent to one skilled in the art in light of the present specification. In the fully collapsed position, the second stub axle shaft 82 will have rotated clockwise seventy or eighty degrees from the illustrated position about the stub axle shaft 76.
In the collapsed configuration, the container 70 can be easily stored or transported. To restore the container 70 to its assembled condition, the above described process is simply reversed.
The bag supporting chute 44 (as well as the front and rear bag supporting members 116 and 118) can be constructed of discrete members or alternatively integrally molded from high quality plastic, nylon or the like. Although virtually any type of material can be employed to construct the frame 12 (72), aluminum tubing is considered best and medium gage steel wire can be used for constructing the frames 26, 32 and 38 once they have been protected from corrosion such as by plating or painting. Lightweight and structural integrity are important primary design considerations in practicing the present invention.
It is to be understood that the invention has been described with reference to a specific preferred embodiment which provides the features and advantages previously described, and that such specific and alternative embodiments are susceptible of modification as will be apparent to those skilled in the art. For example, the dimensions and proportions as suggested in the drawings and specification can be significantly varied without departing from the spirit of the present invention. Accordingly, the foregoing is not to be construed in a limiting sense. | The present specification discloses a combination dust pan and refuse container constructed of inexpensive lightweight materials which is highly transportable and repositionable from an upright refuse transporting position to a horizontal refuse collecting position. The combination dust pan and container is made up of a framework which distends and substantially encloses a conventional disposable trash bag, four circumferentially spaced ground contacting wheels and a dust pan which depends outwardly from the frame near the mouth of the bag. In the transporting position, all four wheels contact the ground and provide a stable base. In the collecting position, the outwardmost edge of the dust pan and two of the wheels which are on a common axle contact the ground. A handle is provided which projects upwardly in both the transporting and collecting positions to facilitate mobility of the pan/container combination. In the preferred embodiment of the invention, mesh type supporting frames are included for heavy duty application and enhanced bag protection. In the alternative embodiment of the invention, the features of a collapsible container and a dimensionally adjustable framework are disclosed. | 1 |
FIELD OF THE INVENTION
[0001] The instant invention relates generally to ring mechanisms of loose leaf binders and particularly to a ring binder assembly device for repairing and preventing misalignment of the rings in a loose leaf binder.
BACKGROUND OF THE INVENTION
[0002] Ring binders are well-known tools for storing, displaying and organizing paper and other similar materials and are useful in a variety of settings; for example, in schools and offices. Ring binders are produced in many different shapes, styles and sizes for both aesthetic and functional purposes. The size is usually dependent upon the diameter of the ring closures, non-limiting examples include, ring closures of a half-inch, one inch, one and a half inches, 2 inches, 3 inches, 4 inches and 5 inches in diameter. Additionally, the rings can be crafted into various shapes for different purposes, non-limiting examples include, D-ring and continuous curvature.
[0003] While binders can be crafted in a variety of shapes, styles and sizes; they all generally share the same common binder ring mechanism. This mechanism is usually spring-loaded and when engaged will quickly and efficiently clamp together to join opposing sides of the rings of the binder. However, due to the pressure exerted on the spring mechanism from repeated use, part and/or all of the ring and/or rings move out of alignment and cease to clamp tightly together. The ease of sifting through the contents of the ring binder is impaired and items may be lost from the binder due to slipping out from misaligned rings. This misalignment of the rings essentially destroys the function of the binder.
[0004] Without a quick and/or easy method of repair, the owner of the binder often purchases a replacement, costing both time and money. Thus, there remains a need in the art to mend this fundamental weakness in the design of ring binders by repairing and preventing misalignment of the rings, extending the “life” of the binder and saving the owner both time and money.
DESCRIPTION OF THE PRIOR ART
[0005] U.S. Pat. No. 4,690,580 discloses a ring binder mechanism of the type referred to wherein the ring portions are reliably adjusted on all sides in their closed position even with heavy loading and are secured against opening of the ring closure by displacement of the ends of the ring portions.
[0006] U.S. Pat. No. 5,765,956 discloses a device for perfected closure of the mechanism having flat rings for containers of mobile sheets (binders). The device comprises rings and screws which are formed with a single presswork operation together with a strip to be placed at the disposal of the user. The latter with simple coin screws within suitable orifices formed on the strip, the latter being fixed to the internal surface of the folder. There is also provided that each ring may be closed simply by causing projections which are formed on the base of each ring to penetrate within shaped grooves, the latter being formed at the opposite end of the same ring, an operation which is easy due to the elasticity of the material which constitutes the rings.
SUMMARY OF THE INVENTION
[0007] The instant invention provides a ring binder assembly device that can both prevent misalignment of binder rings and repair binder rings which have become misaligned. The device of the preferred invention is both a resilient and flexible structure which substantially surrounds the existing binder rings. The device is comprised of at least two hollow tubes of continuous curvature which engage upon closing of the rings to form a single unit. The hollow tubes are sized to substantially cover the entire underlying binder ring and each can be formed as unitary or segmented elements. Since it has been theorized that a funnel-shape can guide a smaller object to a specific point, one end of one of the hollow tubes is molded into a funnel-shape. Through use of this funnel-shape, the device of the instant invention renders it possible to guide one part of a ring to the other part of the ring, thus preventing misalignment and forcing the rings to realign properly should they be out of place.
[0008] Accordingly, it is an objective of the instant invention to provide a device which prevents misalignment of binder rings.
[0009] It is a further objective of the instant invention to provide a device which repairs binder rings which have become misaligned.
[0010] It is a still further objective of the instant invention to provide a device which can repair and/or prevent misalignment of binder rings.
[0011] It is yet another objective of the instant invention to provide kits for preventing and repairing misalignment of binder rings comprising the engagement elements of the device of the instant invention.
[0012] Other objects 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
[0013] FIG. 1 is a general view of a ring binder having the device of the instant invention surrounding the second of three rings.
[0014] FIG. 2 is a broken-away view of the third ring of the binder of FIG. 1 ; illustrating a close-up view of the ring binder mechanism known in the prior art.
[0015] FIGS. 3 A-B FIG. 3A is a broken-away view of the second ring of the binder of FIG. 1 ; illustrating a close-up view of the ring surrounded by the device of the instant invention. FIG. 3B is a transverse section of the device surrounding the ring shown in FIG. 3A illustrating the exterior and interior layers of the device of the instant invention.
[0016] FIG. 4 shows a close-up view of a portion of the device separated to illustrate the pieces which engage to secure the device in place surrounding the binder ring.
[0017] FIG. 5 shows a cross-section of a portion of the piece of the device as shown in FIG. 4 .
DEFINITIONS AND ABBREVIATIONS
[0018] The following list defines terms, phrases and abbreviations used throughout the instant specification. Although the terms, phrases and abbreviations are listed in the singular tense the definitions are intended to encompass all grammatical forms.
[0019] As used herein, the term “loose-leaf” refers to sheets of paper or other similar material which are unbound, mobile and contain holes for insertion into ring binders.
[0020] As used herein, the term “existing binder ring” refers to an individual ring mechanism present in a ring binder made of metals, plastics or other similar materials; usually a binder has three existing binder rings.
[0021] As used herein, the term “substantially covering” refers to an amount of covering of the length of an existing binder ring by the elements of the device of the instant invention sufficient to insure that the papers inserted into the ring can be easily flipped through without snagging or becoming caught on the device.
DETAILED DESCRIPTION OF THE INVENTION
[0022] This invention provides a device for correction and prevention of the most common problem of ring binders, misalignment of the rings with repeated use.
[0023] A standard continuous curvature binder ring is the most frequently utilized shape of binder ring and is the shape typically surrounded by the ring binder assembly device of the instant invention. An example of such a binder ring is shown in FIGS. 1 and 2 , labeled as number 1 . FIG. 1 shows a general view of a ring binder and FIG. 2 shows a broken-away view of the portion of FIG. 1 labeled by line 2 . FIG. 2 displays a close-up version of the ring binder mechanism known in the prior art. A binder ring surrounded by the device of the instant invention is labeled number 3 in FIG. 1 . FIG. 3A shows a broken-away view of this portion of FIG. 1 labeled by line 3 A. FIG. 3A displays a close-up view of a binder ring surrounded by the device of the instant invention. The device of the instant invention is composed of at least two elements, labeled numbers 4 and 5 in FIG. 3A , each a hollow tube having a shape conforming to the curvature of the binder ring which the device will surround. The at least two elements can be of unitary or segmented construction; for example, elements 4 and 5 represent continuous unitary construction wherein each element substantially covers half of the length of an existing binder ring and elements 6 , 7 , 8 and 9 shown in FIG. 3A represent segmented construction wherein each element substantially covers about a quarter of the length of an existing binder ring. Thus, as shown in FIG. 3A , elements 6 and 7 are engaged to form element 4 and elements 8 and 9 are engaged to form element 5 , elements 4 and 5 are then engaged to form the device of the instant invention. The device is often segmented into four elements to facilitate sliding around the existing binder ring during device installation. The device, when completely assembled, should have a diameter of about one to two millimeters greater than the diameter of the existing binder ring for an appropriate fit to insure both proper functioning of the device and substantial covering of the existing binder ring when the ring is in a closed position. This is accomplished by increasing the length of elements 4 and 5 to exceed the length of one half of the existing binder ring in the closed position to insure that elements 4 and 5 are in axial alignment when the device is engaged.
[0024] Elements 4 and 5 , whether of unitary or segmented construction, are continuous curvature hollow tubes comprising an exterior shell constructed of metal or polymeric material and preferably includes an inner layer of rubber or other elastomeric material. FIG. 3B illustrates element 5 of the device cut transversely to show both the exterior polymeric surface and the elastomeric inner layer, labeled as numbers 10 and 11 respectively in FIG. 3B . The section of FIG. 3A shown in detail in FIG. 3B is labeled with line 3 B in FIG. 3A . The material of the exterior surface must be durable enough to withstand pressure from the spring loaded mechanism when the mechanism is opening and closing but not too rigid to prevent the device from easily sliding over the existing binder rings. The interior coating is frequently necessary to prevent excessive degrees of movement of the device after installation since excessive movement may impair the function of the device. The fit of the device to the existing binder ring should be sufficiently secure to properly guide each half of the existing binder ring into place in a closed position. The elastomeric material coating the interior of the hollow tubes should also be flexible enough so as not to impede the sliding of the device over the existing binder rings during installation and may further include a thin layer of adhesive for increased adherance to the binder ring. The elastomeric inner layer should be one millimeter or less in width to allow sufficient space for secure enclosure of the existing binder rings.
[0025] The engagement of the two opposing elements 4 and 5 gives the device the ability to repair and prevent misalignment of binder rings. One end of element 4 (or element 7 if the device is of segmented construction) is crafted into a funnel shape. Utilization of the funnel shape enables the device of the invention to guide one half of an existing binder ring to the other half of the ring in axial alignment, thus preventing misalignment and forcing the rings to realign properly should they be out of place. The funnel-shaped end has an increased diameter as compared with the diameter of the straight-edged end, preferably an increase of at least about 4 millimeters. FIG. 4 is a close-up view of the opposing ends of elements 4 and 5 in a separated position. Elements 4 and 5 are constructed and arranged for juxtaposed circumferential engagement. FIG. 4 shows the funnel-shaped end labeled number 12 and the straight-edged end labeled number 13 . Ends 12 and 13 represent male-female mating portions which engage uniformly upon closing of the ring to substantially cover the existing binder ring to prevent and/or repair ring misalignment. FIG. 5 shows a cross-section of element 4 labeled number 14 . The location of the cut of the cross-section is indicated by line 14 A in FIG. 4 .
[0026] The engagement elements that compose the ring binder assembly device of the instant invention can be conveniently packaged as kits. The engagement elements included within the kits can be of unitary construction, segmented construction or a combination of constructions. Additionally, the engagement elements can be sized for binder rings differing in circumference, for example, but not limited to, binder rings of a half inch, one inch, one and a half inches, two inches, three inches, four inches or five inches. Kits can be packaged including engagement elements of one circumference or of different circumferences.
[0027] In this manner, the ring binder assembly device of the instant invention extends the useful “life” of ring binders.
[0028] All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. 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 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. One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims. | The invention provides a ring binder assembly device to insure the perfected closure of loose leaf binder rings. Enclosure of binder rings with the device of the invention will repair and prevent ring misalignment. | 1 |
This application is a continuation of prior U.S. application Ser. No. 7/062,762, filed June 15, 1989, abandoned.
TECHNICAL FIELD
This invention relates to improvements in processing and apparatus for upgrading the octane of a mixed hydrocarbon gasoline feedstock by an integrated adsorption-isomerization process which catalytically isomerizes normal paraffinic hydrocarbons and concentrates non-normals in a product stream.
The known technology for improving the octane rating of certain hydrocarbon fractions, especially mixed feedstocks containing normal and iso pentanes and hexanes, typically involves isomerizing normal hydrocarbons in a feed stream prior to or following an adsorption-desorption cycle which isolates non-normals.
According to one widely used process, the entire feed is subjected to an initial catalytic reaction and then to a four-stage separation procedure employing molecular sieve adsorbers operating at essentially isobaric and isothermal conditions. Prior to the four-stage procedure, the reactor effluent is separated into an adsorber feed stream and a hydrogen-rich gas stream. The adsorber feed stream is passed to the adsorbers in two adsorption stages: the first, displacing void space gas from a prior desorption stage; and, the second, producing an adsorption effluent having a greatly reduced content of adsorbed (e.g., normal) hydrocarbons. The adsorbers are then desorbed with a hydrogen-rich gas stream in two stages: first to displace void space gas from the preceding adsorption stage; and, second to remove adsorbed hydrocarbons from the adsorbent. This is known as a reactor-lead process.
According to another known process, the feed is first passed to the adsorbers which immediately remove non-normals, again in a four-stage adsorption procedure. The normals from the second desorption stage are then mixed with sufficient hydrogen to protect the isomerization reactor and are then isomerized, with subsequent removal of newly-formed non-normals and recycle of normals to the reactor. This is known in the art as an adsorber-lead process.
By operating the four-stage adsorber cycle in the manner done in the prior art, substantially all hydrogen or other purge gas is removed from the adsorber feed prior to adsorption, and the adsorption effluent varies greatly in molecular weight, from about 10 lb/lb mole at the beginning of adsorption to about 70 lb/lb mole at the end. Because the heat exchange system must be adequate to operate at minimum heat content (i.e., lowest molecular weight), it has been necessary to exaggerate the size of the heat exchangers and to waste heat from the high heat content portion. It would be desirable to produce an adsorption effluent which showed less variation in molecular weight.
The adsorbers operate essentially as a batch procedure. To approach a continuous flow of adsorber effluent with a four-stage adsorber cycle, the prior art has typically employed four adsorbers operated in timed relationship. It would be desirable to reduce the capital cost of the adsorbers and related conduits, valves and controls.
While increasing adsorber operating pressure increases the partial pressure of normals and should, therefore, improve its adsorption, increasing the pressure in prior art adsorbers does not give the desired increase in adsorption efficiency. The adsorbers are filled with solid molecular sieve adsorbent and have significant void space volumes not occupied by solid material. Operating the adsorbers as in the prior art, but at increased pressures, has the disadvantage of increasing void space storage of gases being processed. It would be advantageous to achieve a better proportion of adsorbed normals to void space storage of hydrocarbon.
It would further be desirable to decrease the total adsorbent bed volume and to improve the energy efficiency in an integrated isomerization-adsorption process which could achieve total isomerization of all normal hydrocarbons.
Most preferably, it would be desirable to increase the degree of integration of the reactor and adsorber operations to save energy and decrease the amount of molecular sieve materials and vessel volumes required.
BACKGROUND ART
The art has produced a number of integrated isomerization-adsorption systems for isomerizing a feed stream containing normal and non-normal hydrocarbons and producing a product stream which is useful as a gasoline blending feedstock.
Most of the prior art systems totally isomerize the normals in the feed and are referred to in the art as total isomerization processes, i.e., TIP. Among these are reactor-lead systems, where the fresh feed and any recycle is fed to the isomerization reactor prior to separation of non-normals, and adsorber-lead systems, where the fresh feed is fed to the adsorbers prior to isomerization. As currently operated, both of these schemes typically employ three or four adsorber beds which are cycled through at least one adsorption stage and two desorption stages.
In Canadian Patent No. 1,064,056, Reber et al describe a total isomerization process wherein large fluctuations in the concentration of either n-pentane or n-hexane in the reactor feed are prevented by suitably controlling the operation of a three-bed adsorber system. According to the disclosure, no more than two beds are being desorbed at any given time and the terminal stage of desorption in one of the three beds is contemporaneous with the initial stage of desorption in another of the three beds.
Both adsorber-lead and reactor-lead processes are specifically exemplified. The adsorber-lead process calls for first separating hydrogen from the reactor effluent. Fresh feed is then combined with the reactor hydrocarbon effluent and the combined stream is passed through the adsorbers to remove non-normal hydrocarbons so that the feed to the reactor is essentially normal hydrocarbons. This requires heat exchange equipment of significant size to handle streams of widely varying molecular weight and large energy inputs to cool the entire reactor effluent to separate the hydrocarbon and hydrogen portion, and then to reheat both. The reactor-lead process is similar in this regard.
In U.S. Pat. No. 4,210,771, Holcombe describes a reactor-lead total isomerization process which reduces the recycle rate to the reactor while maintaining a sufficient reactor hydrogen partial pressure by reducing fluctuations in hydrocarbon flow rates to the reactor. However, this reactor-lead process required cooling the entire reactor effluent to separate hydrogen from hydrocarbon portions prior to separating the normals from non-normals in a four-stage adsorption section.
The effluent from the isomerization reactor is condensed to separate a hydrocarbon fraction. This fraction is then reheated and passed as feed in the vapor state and at superatmospheric pressure periodically in sequence through each of at least four fixed beds of a system containing a zeolitic molecular sieve adsorbent having effective pore diameters of substantially 5 Angstroms, each of said beds cyclically undergoing the stages of:
A-1 adsorption-fill, wherein the vapor in the bed void space consists principally of a non-sorbable purge gas and the incoming feedstock forces the said non-sorbable purge gas from the bed void space out of the bed without substantial intermixing thereof with non-adsorbed feedstock fraction;
A-2 adsorption, wherein the feedstock is cocurrently passed through said bed and the normal constituents of the feedstock are selectively adsorbed into the internal cavities of the crystalline zeolitic adsorbent and the nonadsorbed constituents of the feedstock are removed from the bed as an effluent having a greatly reduced content of normal feedstock constituents;
D-1 void space purging, wherein the bed, which is loaded with normals adsorbate to the extent that the stoichiometric point of the mass transfer zone thereof has passed between 85 and 97 percent of the length of the bed and the bed void space contains a mixture of normals and non-normals in essentially feedstock proportions, is purged countercurrently, with respect to the direction of A-2 adsorption, by passing through the bed a stream of a non-sorbable purge gas in sufficient quantity to remove said void space feedstock vapors but not more than that which produces about 50 mole percent, preferably not more than 40 mole percent, of adsorbed feedstock normals in the bed effluent; and
D-2 purge desorption, wherein the selectively adsorbed feedstock normals are desorbed as part of the desorption effluent by passing a non-sorbable purge gas countercurrently with respect to A-2 adsorption through the bed until the major proportion of adsorbed normals has been desorbed and the bed void space vapors consist principally of non-sorbable purge gas.
This process results in wide fluctuations in the molecular weight of the adsorption effluent, has considerable complexity and requires all recycled hydrocarbons and hydrogen to be cooled and reheated.
There is a present need for improvements in isomerization-adsorption systems which will reduce energy consumption while preferably reducing adsorber bed volume and the overall complexity of the adsorption section.
SUMMARY OF THE INVENTION
The present invention is based upon the discovery that considerable improvements can be achieved in terms of reduced adsorbent inventories, reduced adsorption section complexity, and improved energy efficiency, for an integrated isomerization-adsorption process for upgrading light naptha feeds by implementing changes which are contrary to conventional technology. The invention provides improved apparatus and methods for increasing the non-normal content of a feed stream containing normal and non-normal hydrocarbons by a new integration of isomerization and adsorption technologies in both the adsorber-lead and reactor-lead modes.
The process upgrades a hydrocarbon feed containing non-normal hydrocarbons and normal pentane and hexane to produce a hydrocarbon stream enriched in non-normals and includes: passing an adsorber feed stream, comprising hydrogen and hydrocarbons, to an adsorption section containing an adsorbent bed to adsorb normal hydrocarbons from said feed and to pass non-normal hydrocarbons and hydrogen out of the adsorption section as adsorption effluent; passing hydrogen-containing purge gas through said adsorbent bed containing adsorbed normal hydrocarbons to produce a desorption effluent comprising hydrogen and normal hydrocarbons; and passing at least a portion of said desorption effluent to an isomerization reactor to produce a reactor effluent comprising hydrogen and a reactor hydrocarbon component comprising an enhanced proportion of non-normal to normal hydrocarbons. The invention enables improved integration of the two technologies of isomerization and adsorption-desorption.
When operating in the reactor-lead mode, the adsorber feed stream comprises reactor effluent, preferably prior to any significant cooling or component separation. This supplies hydrogen to the adsorber bed and conserves the heat value of the hydrogen and hydrocarbon components. Additionally, this embodiment enables recycle of the majority of the hydrocarbon based on weight in a given cycle, without cooling to any significant degree. Preferably, the only hydrogen which will require cooling and separation from a hydrocarbon component is that which is recycled for desorption. The desorption effluent in this embodiment contains hot hydrogen and hydrocarbons and is preferably not cooled or fractionated prior to recycling for isomerization of normal hydrocarbons. This embodiment can be effectively carried out by placing the isomerization catalyst and the molecular sieve adsorbent in the same vessel.
When operating in the adsorber-lead mode, the adsorber feed stream comprises fresh hydrocarbon feed and recycle, comprising hydrogen and hydrocarbons, from the reactor. The recycle from the reactor is preferably reactor effluent taken off directly without significant cooling or component separation. This hot recycle provides hydrogen to the adsorbent bed and conserves the heat value of the hydrogen and hydrocarbon components.
The apparatus of the invention provides means for performing the above processes.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and its advantages will be more apparent from the following brief description when read in connection with the accompanying drawings wherein:
FIG. 1 is a schematic of a reactor-lead process and an apparatus arrangement which employs two pairs of reactor and adsorber sections wherein each reactor/adsorber pair is in a single vessel;
FIG. 2 is a simplified schematic of a variation on the embodiment of FIG. 1, which employs a valve manifold to maintain the same direction of flow throughout a cycle;
FIG. 3 is another embodiment of a reactor-lead process and apparatus of the invention employing a single reactor vessel; and
FIG. 4 is a schematic of an adsorber-lead process and apparatus arrangement according to the invention wherein a portion of the isomerization reactor effluent is combined with hydrocarbons from fresh feed and recycle to form an adsorber feed.
SUITABLE FEEDSTOCKS (FRESH FEED)
The fresh feed contains normal and non-normal hydrocarbons. It is composed principally of the various isomeric forms of saturated hydrocarbons having from five to six carbon atoms. The expression "the various isomeric forms" is intended to denote all the branched chain and cyclic forms of the noted compounds, as well as the straight chain forms. Also, the prefix notations "iso" and "i" are intended to be generic designations of all branched chain and cyclic (i.e., non-normal) forms of the indicated compound.
The following composition is typical of a feedstock suitable for processing according to the invention:
______________________________________Components Mole %______________________________________C.sub.4 and lower 0-7i-C.sub.5 10-40n-C.sub.5 5-30i-C.sub.6 10-40n-C.sub.6 5-30C.sub.7 and higher 0-10______________________________________
Suitable feedstocks are typically obtained by refinery distillation operations, and may contain small amounts of C 7 and even higher hydrocarbons, but these are typically present, if at all, only in trace amounts. Olefinic hydrocarbons are advantageously less than about 4 mole percent in the feedstock. Aromatic and cycloparaffin molecules have a relatively high octane number. Accordingly, the preferred feedstocks are those high in aromatic and cycloparaffinic hydrocarbons, e.g., at least 5, and more typically from 10 to 25 mole percent of these components combined.
The non-cyclic C 5 and C 6 hydrocarbons typically comprise at least 60, and more typically at least 75, mole percent of the feedstock, with at least 25, and preferably at least 35, mole percent of the feedstock being hydrocarbons selected from the group of iso-pentane, iso-hexane and combinations of these. Preferably, the feedstock will comprise no more than 40, and more preferably no more than 30 mole percent of a combination of n-pentane and n-hexane.
SUITABLE ISOMERIZATION CATALYSTS
The isomerization reactor sections (21 and 27 in FIG. 1) contain an isomerization catalyst which can be any of the various molecular sieve based catalyst compositions well known in the art which exhibit selective and substantial isomerization activity under the operating conditions of the process. As a general class, such catalysts comprise the crystalline zeolitic molecular sieves having an apparent pore diameter large enough to adsorb neopentane, SiO 2 /Al 2 O 3 molar ratio of greater than 3; less than 60, preferably less than 15, equivalent percent alkali metal cations and having those AlO 4 --tetrahedra not associated with alkali metal cations either not associated with any metal cation, or associated with divalent or other polyvalent metal cations.
Because the feedstock may contain some olefins and will undergo at least some cracking, the zeolitic catalyst is preferably combined with a hydrogenation catalyst component, preferably a noble metal of group VIII of the Periodic classification of the Elements. The catalyst composition can be used alone or can be combined with a porous inorganic oxide diluent as a binder material. The hydrogenation agent can be carried on the zeolitic component and/or on the binder. A wide variety of inorganic oxide diluent materials are known in the art--some of which exhibit hydrogenation activity per se. It will, accordingly, be understood that the expression "an inorganic diluent having a hydrogenation agent thereon" is meant to include both diluents which have no hydrogenation activity per se and carry a separate hydrogenation agent and those diluents which are per se hydrogenation catalysts. Oxides suitable as diluents, which of themselves exhibit hydrogenation activity, are the oxides of the metals of Group VI of the Mendeleev Periodic Table of Elements. Representative of the metals are chromium, molybdenum and tungsten.
It is preferred that the diluent material possess no pronounced catalytic cracking activity. The diluent should not exhibit a greater quantitative degree of cracking activity than the zeolitic component of the overall isomerization catalyst composition. Suitable oxides of this latter class are the aluminas, silicas, the oxides of metals of Groups III, IV-A and IV-B of the Mendeleev Periodic Table, and cogels of silica and oxides of the metals of the Groups III, IV-A and IV-B, especially alumina, zirconia, titania, thoria and combinations thereof. Aluminosilicate clays such as kaolin, attapulgite, sepiolite, polygarskite, bentonite, montmorillonite, and the like, when rendered in a pliant plastic-like condition by intimate admixture with water are also suitable diluent materials, particularly when said clays have not been acid-washed to remove substantial quantities of alumina.
Suitable catalysts for isomerization reactions are disclosed in detail in U.S. Pat. Nos. 3,236,761 and 3,236,762. A particularly preferred catalyst is one prepared from a zeolite Y (U.S. Pat. No. 3,130,007) having a SiO 2 /Al 2 O 3 molar ratio of about 5 by reducing the sodium cation content to less than about 15 equivalent percent by ammonium cation exchange, then introducing between about 35 and 50 equivalent percent of rare earth metal cations by ion exchange and thereafter calcining the zeolite to effect substantial deammination. As a hydrogenation component, platinum or palladium in an amount of about 0.1 to 1.0 weight percent, can be placed on the zeolite by any conventional method. The disclosures of these above-cited U.S. patents are incorporated herein by reference in their entireties.
SUITABLE ADSORBENTS
The zeolitic molecular sieve employed in the adsorption bed must be capable of selectively adsorbing the normal paraffins of the feedstock using molecular size and configuration as the criterion. Such a molecular sieve should, therefore, have an apparent pore diameter of less than about 6 Angstroms and greater than about 4 Angstroms. A particularly suitable zeolite of this type is zeolite A, described in U.S. Pat. No. 2,883,243, which in several of its divalent exchanged forms, notably the calcium cation form, has an apparent pore diameter of about 5 Angstroms, and has a very large capacity for adsorbing normal paraffins. Other suitable molecular sieves include zeolite R, U.S. Pat. No. 3,030,181; zeolite T, U.S. Pat. No. 2,950,952, and the naturally occurring zeolitic molecular sieves chabazite and erionite. These U.S. patents are incorporated by reference herein in their entireties.
The term "apparent pore diameter" as used herein may be defined as the maximum critical dimension, or the molecular species which is adsorbed by the adsorbent under normal conditions. The critical dimension is defined as the diameter of the smallest cylinder which will accommodate a model of the molecule constructed using the available values of bond distances, bond angles and van der Waals' radii. The apparent pore diameter will always be larger than the structural pore diameter, which can be defined as the free diameter of the appropriate silicate ring in the structure of the adsorbent.
DETAILED DESCRIPTION
The invention will be described primarily according to a preferred embodiment wherein a mixed hydrocarbon feedstock (fresh feed) is upgraded for use as a gasoline blending stock by an integrated combination of adsorption and isomerization.
The invention will first be described in terms of the reactor-lead configuration in conjunction with FIG. 1 which, as a virtual total integration of isomerization and adsorption technologies, enables adsorber and reactor beds to be in the same vessel. This configuration combines the benefits of both reactor-lead and adsorber-lead systems. Normals in the feed can be partially isomerized before adsorption as in the reactor-lead system, thereby making the adsorption section smaller. On desorption, the benefits of adsorber-lead are appreciated. Since essentially normals are fed to the reactor section on desorption, the catalyst volume is utilized more effectively.
Referring to FIG. 1, fresh feed in line 10 is combined in line 12 with hydrocarbon recycle from line 14. This combined hydrocarbon stream is heated by indirect heat exchange with adsorption effluent, carried by line 16 in heat exchanger 18 from which it is passed to furnace 20 where it is heated sufficiently for passage to isomerization reactor section 21 (catalyst bed) and then the adsorption section 22 (adsorbent bed), of vessel 23. It is of course possible to have the catalyst and adsorbent beds in different vessels if desired.
The reactor feed stream in line 24 is formed by combining the hot hydrocarbon stream from furnace 20 with hot reactor effluent from line 26 which contains hydrogen and hydrocarbon components (i.e., hot recycle or hot hydrogen recycle). Suitable control valves and controllers (not shown) direct feed stream 24 to the appropriate one of vessels 23 and 29, which will alternate between the two functions now represented in FIG. 1 as being performed by each of the vessels.
Depending on the particular catalyst composition employed, the operating temperature of within vessels 23 and 29 is generally within the range of 100° to 390° C. and the pressure is within the range of 175 to 600 psia. Desirably, the temperature will be within the range of from 220° to 280° C. and the pressure will be in the range of from 200 to 400, preferably 220 to 300 psia, and most preferably about 250 psia. The catalyst bed is maintained under a hydrogen partial pressure sufficient to prevent coking of the isomerization catalyst at the conditions maintained in the reactor. Typically, the hydrogen partial pressure will be within the range of from 100 to 250, preferably from 130 to 190, psia with the hydrogen, comprising from 10 to 90, preferably from 35 to 75 and most preferably from 45 to 65, mole percent of the reactor contents which are maintained in a gaseous state.
The feed to the reactor will contain, in addition to hydrogen and hydrocarbon reactants, e.g., normal and iso-pentane and hexane, a quantity of light hydrocarbons which are produced during the reaction and possibly as part of feed and makeup. Because these are non-sorbable, they are retained in the process at some equilibrium level and circulate with the recycle stream.
Preferably, the adsorbents in adsorbent beds 22 and 28 have effective pore diameters of substantially 5 Angstroms. The term "bed void space" for purposes of this description means any space in the bed not occupied by solid material except the intracrystalline cavities of the zeolite crystals. The pores within any binder material which may be used to form agglomerates of the zeolite crystals is considered to be bed void space. The two adsorbent beds shown in the system of FIG. 1, each cyclically undergo the two stages of:
ADS--The feed is intentionally mixed with hydrogen prior to introducing it to the feed end of the adsorber, then adsorbed, with product and hydrogen being withdrawn from the effluent end of the adsorber. The hydrogen will typically comprise from 10 to 90 mole percent of the adsorber feed, preferably, from 35 to 65; and most preferably, from 45 to 55 mole percent. Since there is hydrogen present in the feed as well as the product, there is proportionally less variation in the molecular weight of the product and therefore more efficient heat exchange. (There is no A1 step.)
DES--hydrogen is used to desorb the bed in a direction countercurrent to the feed and the total effluent is sent to the isomerization reactor as feed with no internal recycle. (There is no D 1 step.)
The presence of hydrogen in the adsorber feed improves heat exchange. Heat exchange is better for a steady state system than a dynamic system such as conventional TIP. The heat content of a process stream such as the adsorption effluent is a function of the molecular weight of the stream, which varies from about 10 lb/lb mole at the beginning of the step to about 70 lb/lb mole at the end of the step in the standard conventional TIP process. Since the heat exchange system must be designed to operate at the minimum heat content level, a significant amount of the high heat content portion cannot be utilized effectively. In the present invention, the molecular weight of the adsorption effluent varies from about 10 to 40 lb/lb mole.
In a steady state system there would be no variation in molecular weight. Hence, a mathematical relationship showing the approach to a steady state system ca be developed as follows:
% SS=(AMW-Deviation from AMW)/AMW
where,
AMW=average molecular weight
Deviation from AMW=(Maximum molecular weight-AMW)
For the standard conventional TIP the % SS is calculated as follows:
% SS=(40-(70-40))/40=25%
Similarly, for the present invention the % SS is:
% SS =(25-(40-25))/25=40%
It can be seen that the 40% value for the present invention system is significantly closer to the theoretical steady state value of 100% than the standard conventional value of 25%.
The invention also provides better adsorber and reactor integration which results in further advantages. Although it is clear that the number of adsorbers in the present invention is advantageously reduced from 4 to 2, it is not obvious why the adsorbent inventory is lower, and why the integration of the adsorber and catalyst is necessarily better in light of the increased flow to the catalyst section.
The adsorbent inventory of the present invention is lower than for an equivalent standard conventional TIP system because there are less normal paraffins processed through the adsorbers. In a conventional TIP system, the D1 step (initial part of desorption) performs two functions: one is to prevent hydrogen lean desorption effluent from contacting the catalyst, and the other is to recycle the D1 effluent back to the adsorbers for readsorption. The effect is to maximize the adsorber size and minimize the reactor size. In the present invention, the portion of the desorption effluent that would be D1 is passed directly to the isomerization reactor where it is further isomerized and then recycled back to the adsorbers. Hence, since the effluent has been further isomerized before being recycled to the adsorbers, fewer normals are ultimately recycled and the adsorbent inventory can be lower.
Since there is hydrogen present in the adsorber feed, and since adsorber capacity is a function of the normals partial pressure in the feed, it would be expected that the adsorber capacity should be slightly lower in the present invention (the effect is slight because at the normal partial pressures of the two cases, at greater than 50 psia, the adsorbent loading is about 90% of total capacity). However, this can be compensated for by operating the adsorbers at a higher pressure in order to increase the normals partial pressure. In fact, higher pressure operation is an advantage in the present invention but cannot conveniently be utilized in the conventional TIP system. In the conventional TIP system, an increase in operating pressure would result in only a marginal increase in adsorption capacity but would substantially increase the unwanted void space storage since it is directly proportional to the total pressure. Further, an increase in operating pressure would require a corresponding increase in operating temperature in order to prevent condensation. In the present invention, an increase in operating pressure is desirable since it increases the normals partial pressure so as to be comparable to the conventional TIP system; however, since the hydrogen is present, the pressure increase does not have as great a detrimental effect on void storage. In addition, a corresponding temperature increase would not be required since the condensation temperature is much lower for the hydrogen-containing feed.
The catalyst volume in a conventional TIP system is calculated as a function of the average feed rate in weight units. Since the initial portion of the desorption effluent, D1 effluent, is recycled to the adsorbers before being fed to the reactor, the average flow rate for the conventional TIP system is lower than for the present invention. It would be expected that the catalyst volume required should be proportionally higher for the present invention. However, a smaller than expected catalyst volume can be effectively used in the present invention because of the high isomer content of the initial portion of the desorption effluent. That is, some portion of the initial effluent can be passed through at a feed rate higher than usual since it is already partially isomerized. The remainder of the desorption effluent, which is low in isomer content, can be passed through the reactor at a more typical feed rate. The net result is that even though the reactor feed rate is significantly higher in the present invention, the increase in catalyst volume is not proportional since the invention makes it possible to utilize the high isomer/high flow rate portion of the desorption effluent more effectively than in conventional TIP.
The following description details an operation wherein bed 22 is undergoing adsorption, and bed 28, desorption. The reactor feed from line 24 is directed via suitable lines, manifolds, and valves (not shown) to vessel 23 for isomerization in catalyst bed 21 to produce a reactor effluent enriched in non-normals which is passed to adsorbent bed 22 undergoing adsorption. Each of the adsorbent beds in the system, namely beds 22 and 28 contain a molecular sieve adsorbent in a suitable form such as cylindrical pellets.
At the time that reactor effluent from catalyst bed 21 starts entering adsorbent bed 22, the bed contains residual purge gas from the preceding desorption stroke. The purge gas is preferably hydrogen-containing because of the need to maintain at least a minimum hydrogen partial pressure in the isomerization reactor. This is supplied to the adsorbent beds during desorption as a purge gas recycle stream via line 50. Feed through line 24 first flushes bed 22 of residual hydrogen-containing purge gas. This does not, however, end the stage and reactor effluent from bed 21 continues to flow as adsorber feed to adsorbent bed 22 with the production of adsorption effluent drawn off via line 16.
As adsorption continues, the normal paraffins in the feed are adsorbed by bed 22, and an adsorption effluent, i.e., hydrogen and the non-adsorbed non-normals, emerges from the bed through suitable valves and manifold arrangement (not shown). The adsorption effluent flows through line 16, heat exchanger 18, air cooler 32 and heat exhanger 34 prior to separation into a hydrogen-containing overhead product for recycle and an isomerate product in separator 36.
The overhead gas is recovered by separator 36 and combined with a similar overhead product from separator 40 which separates the reactor effluent takeoff from reactor bed 27 in line 42 into an overhead product taken off by line 42 and a reactor hydrocarbon product which is withdrawn via line 14 as described above. The combined stream formed from lines 38 and 44 is fed via line 46 to recycle compressor 48 for return via line 50 to the vessel having the adsorbent bed undergoing desorption. In this case appropriate valves direct flow to to heat exchanger 52 and heater 54 prior to entering vessel 29, containing bed 28 for desorption.
The effluent from bed 28, passes directly to reactor bed 27. During the desorption stage, void space adsorber feed is first purged, followed by desorption of selectively-adsorbed normal paraffins from the zeolitic molecular sieve. The desorption effluent from bed 28 will, throughout the stage, comprise hydrogen and hydrocarbons. The desorption effluent passes directly to isomerization reactor bed 27 as reactor feed.
The foregoing description is for a single stage of a total two stage cycle for the system. For the next stage, appropriate valves are operated so that vessel 29, containing catalyst bed 27 and adsorbent bed 28 receives feed to the reactor bed which passes reactor effluent to bed 28 for adsorption, and bed 22 in vessel 23 begins desorption with the desorption effluent passing directly to catalyst bed 21. At the end of two stages, both adsorbent beds have gone through the stages of adsorption and desorption.
The isomerization process will result in some hydrogen losses from the purge gas due to hydrogenation of starting materials and cracked residues. Hydrogen will also be lost due to solubility in product, and possibly a vent from line 50 (not shown) which can be controlled by suitable valve means. These losses require the addition of makeup hydrogen. Makeup hydrogen can be supplied in impure form, e.g., via line 62, typically as an offgas from catalytic reforming or steam reforming of methane. These hydrogen sources are suitably pure for isomerization processes which typically have a vent from the recycle stream. Refinery streams of lesser purity may also be satisfactory. The desorption effluent in line 58 will comprise desorbed normal hydrocarbons, e.g., n-pentane and n-hexane, and hydrogen and light hydrocarbon and other impurities which comprise the purge gas used for desorption. This effluent is reactor feed and is passed to isomerization reactor 60.
A portion (up to 100%) of the reactor effluent from bed 27 is split off from line 64 via line 26 as a hot hydrogen-containing stream (i.e., hot recycle or hot-hydrogen recycle) for feed to the vessel 23, first to reactor bed 21 and then to adsorbent bed 22 undergoing adsorption. Preferably, at least 10% and most preferably from 25 to 75%, on a weight basis, will be recycled to the first reactor in this manner. The remainder of the reactor effluent is passed to heat exchanger 66 where its sensible heat is used to heat the combined hydrocarbon stream in line 12 which includes fresh feed. From the heat exchanger 66, reactor effluent in line 42 is further cooled by air cooler 68 and water cooler 70 prior to separation as discussed above in separator 40.
The advantages of this invention can be appreciated in a number of ways. An important concept in all of the schemes is that some or all of the hydrogen used in the desorption step is fed to an adsorber bed undergoing adsorption as hot recycle from either the reactor effluent or the desorption effluent, depending on the particular configuration used. The term, hot recycle or hot-hydrogen recycle, means hydrogen-rich gas which has been previously heated for some purpose and is utilized a second time to improve the thermal efficiency of the process. It should also be noted that the invention also applies to the partial recycle process as described in the U.S. Pat. No. 4,709,116, issued Nov. 24, 1987 the disclosure of which is hereby incorporated by reference.
As discussed above this hot recycle does not involve a component separation; it is simply a stream or stream division. One of its major functions is to provide the necessary hydrogen in the adsorption step to prevent catalyst coking when the desorption effluent is passed to the reactor. In addition to providing the necessary hydrogen, the hot recycle carries with it a substantial portion of the reactor effluent that must ultimately be recycled to the adsorbers. This mode of operation reduces the process cooling and heating requirements that would otherwise be required. It is important to note that the amount of hot recycle must be balanced between maximizing the amount of hydrocarbon reactor effluent recycled and minimizing the amount of hydrogen recycled. (Maximizing the hydrocarbon recycle reduces energy consumption and minimizing hydrogen recycle increases the adsorption capacity.)
This hot recycle is different than the D1 recycle used in the conventional TIP. It is undesirable to have hydrogen present in the D1 effluent whereas in the present invention its primary purpose is to provide hydrogen. In addition, the hot recycle in the embodiments of FIGS. 1, 2 and 4 of the present invention originates from the reactor and not from the adsorbers as in the conventional TIP. This step is likewise different from the reactor effluent recycle used in the noted partial recycle process and conventional TIP since the purpose of those steps is to recycle a hydrogen-free adsorber feed.
Considering the reactor-lead configuration, at least two more variations are possible. In certain cases it may be more beneficial to maintain the flow through the catalyst (beds C1 and C2) in one direction rather than alternating between both directions as described in the configuration of FIG. 1. FIG. 2 illustrates one way that this can be accomplished with a simple valve manifold, which alternates the flow through beds C1 and C2 but maintains flow in the same direction through adsorbent beds ADS and DES. Other methods such as a side draw port might be feasible when a compound bed as in FIG. 1 is used.
A third variation of the reactor lead configuration is to combine the two reactor sections (C1 and C2) in a single vessel. This scheme might be used if it would be impractical, for some reason, to utilize the compound bed approach. FIG. 3 shows that there is one feed pass through the larger reactor, followed by adsorption (ADS) then desorption (DES) with hydrogen. In this case, the hot hydrogen recycle is provided by the desorption effluent and not the reactor effluent.
FIG. 4 shows an adsorber-lead configuration which achieves the advantages of the invention and is characterized by a two stage adsorber cycle and the use of a hot hydrogen recycle which employs reactor effluent, without substantial cooling or separation of components, as a portion of adsorber feed. Fresh feed in line 110 is combined in line 112 with reactor hydrocarbon product from line 114. This combined hydrocarbon stream is heated by indirect heat exchange with adsorption effluent, carried by line 116 in heat exchanger 118 from which it is passed to furnace 120 where it is heated sufficiently for passage to the adsorption section 122.
The adsorber feed stream in line 124 is formed by combining the hot hydrocarbon stream from furnace 120 with hot reactor effluent from line 126 which contains hydrogen and hydrocarbon components. Suitable control valves and controllers (not shown) direct the adsorber feed stream directed to the appropriate bed in the adsorption section (shown here as bed 122).
The adsorber feed, containing normal and non-normal hydrocarbons in the vapor state, is passed at superatmospheric pressure periodically in sequence through each of a plurality of fixed adsorber beds, e.g., two as shown in FIG. 4. It is of course possible to employ a greater number of beds if desired; however, it is an advantage of the invention that only two are required. In a two bed system, each of the beds cyclically undergoes the two stages (ADS and DES) described with reference to FIG. 1.
Referring again to the adsorption section in particular, the following description details an operation wherein bed 122 is undergoing adsorption, and bed 128, desorption. A portion of the adsorber feed from line 124 is directed via suitable lines, manifolds, and valves to adsorbent bed 122 undergoing adsorption.
Flow of the adsorber feed through line 124 first flushes bed 122 of residual hydrogen-containing purge gas, and adsorber feed continues to flow to adsorbent bed 122 with the production of adsorption effluent drawn off via line 116.
As adsorption continues, the normal paraffins in the feed are adsorbed by bed 122, and an adsorption effluent, i.e., hydrogen and the non-adsorbed non-normals, emerges from the bed through suitable valves and manifold arrangement (not shown). The adsorption effluent flows through line 116, heat exchanger 118, air cooler 132 and heat exhanger 134 prior to separation into a hydrogen-containing overhead product for recycle and an isomerate product in separator 136.
The overhead gas can be recovered by separator 136 is combined with a similar overhead product from separator 140 which separates the reactor effluent takeoff in line 142 into an overhead product recovered in line 144 and a reactor hydrocarbon product which is withdrawn via line 114 as described above. The combined stream formed from lines 138 and 144 is fed via line 146 to recycle compressor 148 for return to the adsorber section via line 150 for desorption of bed 128.
From compressor 148, the hydrogen-containing purge gas stream is passed via line 150 to heat exchanger 152 and heater 154, wherein it is heated and then passed to bed 128 which is undergoing desorption.
The effluent from bed 128, passes through suitable valves and manifold (not shown) to reactor 160 via line 158. During the desorption stage, void space adsorber feed is first purged, followed by desorption of selectively-adsorbed normal paraffins from the zeolitic molecular sieve. The desorption effluent from bed 128 will, throughout the stage, comprise hydrogen and hydrocarbons. The desorption effluent is sent to isomerization reactor 160 via line 158 as reactor feed.
The foregoing description is for a single adsorber stage time period of a total two stage cycle for the system. For the next adsorber stage time period, appropriate valves are operated so that bed 128 begins adsorption and bed 122 begins desorption. Similarly, a new cycle begins after each adsorber stage time period; and, at the end of the two cycle time periods, both beds have gone through the stages of adsorption and desorption.
Makeup hydrogen, as needed, can be supplied, e.g., via line 162. The desorption effluent in line 158 will comprise desorbed normal hydrocarbons, e.g., n-pentane and n-hexane, and hydrogen and light hydrocarbon and other impurities which comprise the purge gas used for desorption. This effluent is reactor feed and is passed to isomerization reactor 160.
The effluent from the reactor 160 flows via line 164. A portion of the reactor effluent is split off of line 164 via line 126 as a hot hydrogen-recycle for feed to the adsorbent bed undergoing adsorption. Up to 100% of the reactor effluent can be recycled in this manner to the adsorbent bed undergoing adsorption. Preferably, at least 10%, and most preferably from 25 to 75% will be recycled. The remainder of the reactor effluent is then passed to heat exchanger 166 where its sensible heat is used to heat the combined hydrocarbon stream in line 112 which includes fresh feed. From the heat exchanger 166, reactor effluent in line 142 is further cooled by air cooler 168 and water cooler 170 prior to separation as discussed above in separator 140.
It is an advantage of the invention that existing TIP equipment can be modified to greatly increase feed throughput and final product production while still providing octane values sufficient for use as a gasoline blending stock.
The following example will help to illustrate and explain the invention, but is not meant to be limiting in any regard. Unless otherwise indicated, all parts and percentages are on a molar basis.
EXAMPLE 1
This example illustrates the operation of a process essentially as shown in FIG. 4. The process design for this example is based on a charge rate of 4000 BPSD of a predominantly C 5 /C 6 feedstock as described in the Table below, which also describes principal process streams.
TABLE__________________________________________________________________________Stream Numbers 110 116 124 126 137 142 158 162 Fresh Adsorp- Total Unstabi- Reactor Desorp- Feed (LVN) tion Adsorption Hot lized Effluent tion Make-up to Unit Effluent Feed Recycle Isomerate Takeoff Effluent Hydrogen__________________________________________________________________________DESCRIPTIONState Liquid Vapor Vapor Vapor Liquid Vapor Vapor VaporTemperature °F. 150 500 500 510 100 510 490 100Pressure, psig 360 242 256 262 220 264 270 220Molecular Weight 79.5 22.9 38.3 21.7 73.9 21.7 21.5 8.6Density, Lbs/FT.sup.3 @ TIP 38.59 0.571 1.006 0.577 38.49 0.581 0.600 0.335Volumetric Flow Rate, 4000 -- -- -- 4250 -- -- --BPSD @ STPVolumetric Flow Rate, -- 124101 123222 84243 -- 125459 202335 1904FT.sup.3 /hr @ TIPWeight Flow Rate, Lbs/hr 38580 70815 124012 48595 39219 72893 121488 639 LB Moles/hrCOMPOSITIONHydrogen -- 1732.0 1278.5 1273.5 5.2 1910.2 3237.4 58.9Methane -- 490.0 370.6 362.1 8.7 543.1 901.7 5.2Ethane -- 87.4 69.5 63.0 7.1 94.5 155.2 4.8Propane -- 85.4 78.2 60.7 18.5 91.0 136.0 2.8Isobutane -- 86.5 92.2 60.1 33.5 90.2 117.6 0.8Normal Butane 2.9 17.1 65.2 38.1 8.1 57.1 90.7 0.7Isopentane 80.5 276.6 376.2 152.5 181.6 228.7 280.6 0.5Normal Pentane 125.2 32.4 304.6 88.8 23.1 133.1 324.2 0.2Cyclopentane 12.5 14.5 21.2 4.1 11.1 6.2 11.7 --2.2-Dimethylbutane 1.8 30.3 43.4 19.3 24.2 29.0 26.3 0.42.3-Dimethylbutane 6.2 23.1 33.9 12.5 19.2 18.7 18.2 --2-Methylpentane 57.6 101.2 150.5 41.5 85.4 62.2 75.9 --3-Methylpentane 35.5 66.9 99.6 28.4 57.0 42.7 49.6 --Normal Hexane 104.1 4.7 165.9 27.0 4.1 40.6 167.6 --Methylcyclopentane 24.6 27.1 41.0 7.2 23.7 10.8 18.9 --Cyclohexane 10.6 10.2 15.5 2.1 9.0 3.2 6.9 --Benzene 13.9 9.1 13.9 -- 7.7 -- 6.2 --Isoheptane 3.8 3.6 5.5 0.7 3.4 1.1 2.2 --Normal Heptane 5.8 0.2 12.9 2.9 0.2 4.4 12.9 --Total 485.0 3098.3 3238.3 2244.5 530.8 3366.8 5639.8 74.3__________________________________________________________________________
A starting point is selected at the discharge stream from the recyle hydrogen compressor 148. This stream is preheated in exchanger 152 against the reactor effluent (Stream No. 142). The hydrogen recycle outlet temperature from 152 is maintained at 358° F., controlling the hydrogen recycle bypass around exchanger 152. The recycle gas is then heated to 510° F. in furnace 154. From 154, the hot hydrogen passes downflow through one adsorber (in this case 128), and strips the adsorbed normals from the molecular sieve adsorbent. Hot desorption effluent (Stream No. 158) is then sent to the isomerization reactor 160. The composition of this stream is shown in the Table.
In the isomerization reactor, the normal paraffins are partially converted to isoparaffins. An improved distribution of isohexanes is also achieved by increasing the concentration of the more highly branched dimethylbutanes. Some ring opening of naphtenes, hydrogenation of aromatics, and cracking of the hydrocarbons to butanes and lighter also occur. The reactor effluent is split, with one stream (Stream No. 126) combining with the adsorber feed, and the other stream of reactor effluent takeoff (Stream No. 142) being cooled by heat exchange against the cold adsorber feed in 166 and against the recycle hydrogen stream 152. The reactor effluent takeoff is further cooled to 140° F. in air cooler 168 and to 100° F. in water cooler 170. It is then sent to the reactor effluent separator 140 for separation of condensed hydrocarbons. The vapor from 140 is routed to the inlet of compressor 148 where it is compressed from 220 to 301 psig. The condensate from 140 is pumped via pump 141 through line 114 and is mixed with the fresh feed stream (Stream No. 110) to form combined hydrocarbon stream in line 112.
The combined hydrocarbon stream 112 is heated against the adsorption effluent (Stream No. 116) in exchanger 118 and against the reactor effluent takeoff in exchanger 166 to the furnace at an inlet temperature of 395° F. In Furnace 120 the combined hydrocarbon stream is heated to 510° F. to provide the required temperature of 500° F. at the adsorber inlet. This feed is then combined with hot recycle in line 126 and to form the total adsorber feed (Stream No. 124) passed upflow through one of two adsorbers (in this case, 122), depending on the position of the cycle, where the normals are adsorbed into the micropores of the molecular sieve adsorbent. Non-normals and a small quantity of displaced hydrogen gas pass through the bed and form the adsorption effluent. The adsorption effluent (Stream No. 116) is cooled against the adsorber feed in heat exchanger 118. It is then air cooled in 132 down to 140° F., and water cooled in 134 down to the temperature of the adsorption effluent receiver 166. The vapor overhead from separator 136 (Stream No. 138) is combined with the vapor overhead from separator 140 and is routed to the inlet to compressor 148. The condensed hydrocarbons from separator 136 form the unstabilized isomerate product. The unstabilized isomerate (Stream No. 137) is sent to stabilization facilities. Hydrogen make-up (Stream No. 162) is supplied as necessary to separator 136.
The two adsorbers (122 and 128) containing molecular sieve adsorbent are both used to separate the normal paraffins from the non-normals in the feedstock. The adsorbers are automatically cycled through sequential steps, by a controller which operates the remote operated valves (ROVs) in the adsorber manifolds (not shown). At any given moment either the two adsorbers are both on the adsorption step or one adsorber is on the adsorption step and one adsorber is on the desorption step. Two cycle timers are set to give the desired step times. The design step times are as follows:
______________________________________Adsorption Step 110 secondsDesorption Step 90 secondsValve Changing 40 secondsTotal Cycle Time 240 seconds______________________________________
The adsorber feed 124 enters the adsorber that is on the adsorption step. The other adsorber is on the desorption step. As the desorption step finishes, the desorption feed is totally bypassed around the adsorbers to the inlet to the isomerization reactor 160. The adsorber that has just finished the desorption step now begins the adsorption step, while the other adsorber finishes the adsorption step. Thus, for a short period of time (20 seconds during valve changes in the four-minute cycle), the two adsorbers are both on the adsorption step.
At the beginning of the adsorption step, the adsorber feed and effluent valves are opening on one bed and closing on the other bed. The adsorber feed, at approximately 500° F. and 256 psia, is fed to the molecular sieve adsorbent bed, which was previously purged with hydrogen. The molecular sieve bed contains synthetic zeolite crystals having interconnecting pores of a precisely uniform size. The pore size of molecular sieve crystals is tailored to accept only molecules with a minimum effective diameter of up to five angstroms. Since the effective molecular diameters of the non-normals in the feed are too large to pass through the pores into the main adsorption sites, only the normals are adsorbed on the bed. The non-normals remain in the void spaces of the bed and displace the purge gas (retained from the previous desorption step) out through the top of the adsorber into the adsorption manifold.
As the adsorption step continues, the non-normals/purge gas interface reaches the top of the adsorber. The composition of the adsorption effluent changes from being mostly purge gas to being mostly non-normals and hydrogen. The adsorber feed continues to pass upflow through the adsorber and the normals continue to be adsorbed on the bed. The quantity of normals adsorbed per unit of molecular sieve (i.e., the loading) approaches an equilibrium level determined by the partial pressure and molecular weight of the normals and by the adsorption temperature. This relationship is illustrated by plotting the isotherms of loading versus partial pressure. The non-normals and hydrogen in the feed, together with some purge gas and a small quantity of normals, pass out of the top of the adsorber into the adsorption effluent manifold. The normals adsorbing in the bed displace about 15 percent of a vessel void volume of purge gas from the micropores. This gas gradually mixes with the non-normals and passes into the adsorption effluent. During the desorption steps, the purge gas establishes a residual loading of normals on the top portion of the adsorber which is in equilibrium with the normals concentration in the vapor. Since the same equilibrium is reached during the adsorption step, the minimum normals concentration in the adsorber effluent is the same as the concentration in the purge gas. As the normals are adsorbed from the incoming adsorber feed, the liberated heat of adsorption creates a temperature front which travels up the bed coincident with the adsorption mass transfer front. The adsorption step is terminated before the mass transfer front reaches the top of the bed (approximately 90 percent bed utilization), thereby preventing a large concentration of normals from breaking into the adsorption effluent and reducing the isomerate purity.
During the beginning of the desorption step, the non-adsorbed C 4 + hydrocarbons, retained in the bed after completion of the adsorption step, are countercurrently displaced with hydrogen purge gas. The displaced hydrocarbons, along with some purge gas, pass out of the bottom of the bed to the Isomerization Reactor.
The purge gas then desorbs normals from the adsorbent by reducing the partial pressure of the normals in the vapor phase, thereby shifting the equilibrium loading to a lower value. Normal pentane and hexane concentrations in the purge gas are maintained at low levels to insure efficient desorption of the adsorbed normals. As the desorption step proceeds, the normals loading on the bed declines and the rate at which normals leave the bed decreases. The desorption step is terminated before all the normals have been removed from the bed. The amount removed during each cycle is based on an economic balance between the adsorber bed investment and the purge gas recirculating costs. Following the completion of the desorption step, the desorption feed and effluent valves close and a desorption feed bypass valve opens. This bed then returns to the adsorption step and continues the sequence of steps just described.
In the isomerization reactor, normal paraffins are partially converted to isoparaffins. A higher octane distribution of isohexane is also achieved by increasing the relative concentration of dimethylbutanes. Some ring opening of naphthenes, hydrogenation of aromatics and feed cracking to butanes and lighter also occur. The performance of the reactor (i.e., conversion and yield) is dependent on space velocity, feed composition, operating temperature and hydrogen partial pressure.
The above description is for the purpose of teaching the person of ordinary skill in the art how to practice the present invention and is not intended to detail all of those obvious modifications and variations of it which will become apparent to the skilled worker upon reading the description. It is intended, however, that all such modifications and variations be included within the scope of the present invention which is defined by the following claims. | Processing and apparatus are provided for upgrading the octane of a mixed hydrocarbon gasoline feedstock by an integrated adsorption-isomerization process which catalytically isomerizes normal paraffinic hydrocarbons and concentrates non-normals in a product stream, in both the reactor-lead and adsorber-lead configuration.
The process includes passing an adsorber feed stream comprising hydrogen as well as hydrocarbons to an adsorbent bed to adsorb normal hydrocarbons. The hydrogen is preferably obtained from a hot hydrogen-containing process stream which is not cooled or separated into component parts prior to forming the adsorber feed. In some embodiments, the hot-hydrogen containing stream comes from reactor effluent and in others from desorption effluent.
According to the invention, the only hydrogen which will require cooling and separation from a hydrocarbon component is that which is recycled for desorption. The invention provides improved energy efficiency and can reduce equipment size and complexity. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a division of application Ser. No. 09/270,799, filed Mar. 17, 1999, now U.S. Pat. No. 6,123,157, a continuation-in-part of U.S. patent application Ser. No. 08/843,613 filed Apr. 10, 1997, now abandoned, which is a continuation-in-part of application Ser. No. 08/510,364 filed Aug. 2, 1995, now abandoned.
FIELD OF THE INVENTION
The present invention relates to anti-vibration adaptors. More specifically, the present invention relates to anti-vibration adaptors which, when employed in conjunction with standard powered fastener drivers and socket-type driven heads, increases the torque transmitted to a fastener and decreases vibration experienced by the fastener driver which is subsequently transmitted to the operator.
DESCRIPTION OF THE PRIOR ART
Power fastener drivers such as pneumatic or electric powered pulse and/or impact wrenches as well as anglehead and/or straight nut runners, referred to herein simply as drivers, are well known in industrial environments. In particular in the automotive industry these types of drivers are used extensively in the assembly of automobiles. Typically such drivers comprise a pistol or club-style main body, a trigger, airline connections and a drive shaft which removably connects with any one of a plurality of driver heads and/or drive shaft extensions.
The driver heads comprise a plurality of various sized Imperial or SAE type sockets and screwdriver fittings, herein referred to as sockets, all of which are used to drive or “run down” a variety of fasteners including nuts and bolts. The variety of sockets available varies with the head style of the fastener. For example, while hexagonal type bolt heads are common, Allen-type and Torx-head bolts are are also used extensively in the automobile industry in a variety of sizes. Typically, the connection between the driver and the socket is accomplished via a male square drive connector on the drive shaft of the driver and a complementary female square drive connector on the socket which may be snapped together and retained by a spring pin disposed through the surface of the male square drive connector. However, other snap-on connector profiles are available which are equally effective. Generally these tools are designed to enable the operator to change sockets quickly depending on the size or head style of the fastener to be run-down, hence the popularity of these types of snap-on connections. However, due to the frequency of socket changes and the fact that the sockets are mass produced items, the majority of these types of drivers and sockets, including automotive industrial grade tooling, are not designed to close tolerances and have relatively large mating clearance. In most instances the resulting connection between the driver and the socket will suffer from two degrees of freedom, first the socket will be free to rotate a few degrees relative to the rotational position of drive shaft and second the rotational axis of the socket will be free deviate a few degrees from the rotational axis of the drive shaft.
In operation, deviation of the rotational axis of the socket from the rotational axis of the drive shaft will result in a circular motion of the end of the drive shaft and vibration of the driver. The relative freedom of rotation of the socket with respect to the drive shaft, particularly when the driver is an impact or pulsing driver, results in vibration of the driver and socket components relative to each other. Consequently, the tool operator is exposed to these vibrations which are transferred through the tool to the operator's hands and arms. In an environment such as the automotive industry where a typical assembly worker's primary function is to operate these drivers, these vibrations can cause serious physical injury. Further, the vibrations result in substantially elevated noise levels which can result in the operator suffering from permanent hearing loss if exposed for sufficient periods of time.
These vibrations have other detrimental effects. In particular, excessive vibration can cause premature breakdown of the internal bearings of the driver. Further, in many circumstances, such as the production of automobiles, fasteners are designed to be installed with a specific torque to which the drivers are preset. The vibrations result in losses in torque applied to the fastener which consequently results in fasteners not tightened to specification during production which results in poor statistical process control.
Overall the above-identified disadvantages of typical socket-driver connections result in torque losses, quality control and operator health problems which increase manufacturing costs and/or reduce final product quality. Therefore there is a long standing need in industry for an apparatus which reduces vibration when employed with a standard driver and socket.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a novel anti-vibration which mitigates at least one of the above described disadvantages of the prior art.
According to one aspect of the invention there is provided an anti-vibration adaptor for use with a standard releasable connection between the drive shaft of a driver and a socket the adaptor comprising: a housing which extends at least partially over both said drive shaft and said socket; a damping means disposed within said housing surrounding, but not intervening between the parts said releasable connection and enclosing at least a portion of said drive shaft and said socket with negligible clearance such that any misalignment of the rotational axes of the drive shaft and said socket is minimized.
According to another aspect of the present invention there is provided an anti-vibration adaptor for use with a driver having a drive shaft and socket coupled to said drive shaft through a releasable connection the adaptor comprising: a hollow cylindrical housing for enclosing said releasable connection and extending at least partially over both said drive shaft and said socket; damping means disposed in said housing having a first bore disposed in one of its ends, coaxially aligned and in communication with a second bore disposed in its opposite end; said first bore having a diameter to permit it to releasably receive a cylindrical portion of said drive shaft with negligible clearance or limited interference and said second having a diameter to permit it to releasably receive a cylindrical portion said socket with negligible clearance or limited interference whereby misalignment of the axes of rotation of said drive shaft and said socket is minimized and rotation of said drive shaft with respect said socket is inhibited.
The present invention further includes an anti vibration adaptor for use in association with a driver having a drive shaft releasably secured by a coupling to an extension shaft comprising: a housing which extends over said coupling and over at least a portion of said drive shaft and said extension shaft, said housing enclosing damping means which surrounds, but does not intervene between, said portions of said drive shaft and said extension shaft, with negligible clearance or slight interference.
Preferably said damping means is formed from Ultra High Molecular Weight (UHMW) polyethylene.
In accordance with the present invention the housing is preferably in the form of a hollow cylinder formed from any one of steel, stainless steel, aluminum, copper, brass, cast iron, and titanium, fibreglass, carbon fibre composites and plastics.
The present invention includes anti-vibration adaptors which fit tightly over both that portion of the socket that contains the releasable connection and a portion of the drive shaft, but does not intervene between the drive shaft and the socket, thereby substantially eliminating axial misalignment of the rotational axis of the socket and the rotational axis of the drive shaft and additionally inhibiting rotational movement of the drive shaft with respect to the socket.
Advantages of the present invention include an anti-vibration adaptor which tightly fits over the conventional joint between a drive shaft on a fastener driver and a driver head thereby eliminating any run-out in the joint.
Advantages of the present invention include reduction of vibration due to misalignment of the rotational axes of the drive shaft and the socket and/or rotational movement of the drive shaft with respect to the socket.
Another advantage of the present invention is that reduction of misalignment of the rotational axis of the drive shaft and the rotational axis of the socket, reduces torque lost due to such misalignment significantly and errors of torque measurement caused by vibration from axial misalignment or from freedom of the drive shaft to rotate with respect to the socket are also reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
Presently preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 shows an exploded view of a pulse wrench, a socket and a section of an anti-vibration adaptor in accordance with an embodiment of the present invention.
FIG. 2 shows a sectional view of a socket mounted on one end of a conventional extension shaft and held in alignment by an anti-vibration adaptor. with the other end of the extension shaft connected to a drive shaft and held in alignment by a further anti-vibration adaptor.
FIG. 3 shows a perspective view of a right angle tool fitted with a tool mounted anti-vibration adaptor and an extension shaft in accordance with a second embodiment of the present invention.
FIG. 4 shows a sectional view of the tool mounted anti-vibration adaptor of FIG. 3 taken along section line 4 — 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An anti-vibration adaptor in accordance with the present invention is shown in FIG. 1 and is indicated generally at 10 . Adaptor 10 generally comprises a housing 14 , a damping means, which in the present embodiment comprises a damping sleeve 18 having a pair of ends 22 and 26 . End 22 is sized to engage a shaft 30 and square drive 34 of a conventional driver such as pulse wrench 38 while end 26 is sized to engage a conventional socket 42 . The size of both ends of the damping sleeve is preferably such as to produce a slight interference fit. The resulting fit may be termed a slip fit. Because of the resilience of the material of the damping sleeve the driver and socket may be assembled or disassembled by hand but the interference inhibits rotary motion between the adaptor, socket and the shaft. Pulse wrench 38 may be any conventional pneumatic or electric driver as, previously described, which typically accommodates ¼″, ⅜″or ½″ square or hexagonal drive type sockets 42 . However, adaptor 10 may be sized to accommodate smaller or larger type socket wrench systems with a variety of drive configurations. It will be noted that the adaptor does not replace the standard coupling between the drive and the socket but merely surrounds it.
Housing 14 generally cylindrical, annular in cross-section and preferably is formed from stainless steel or aluminum having generally smooth inner and outer diameters 46 and 50 respectively. However, it is contemplated that housing 14 may be formed from any suitable material such as steel, brass, copper, titanium, cast iron, composites such as fibreglass or carbon fibre and plastics. Damping sleeve 18 , is provided with an outer diameter which is sized for interference press fit engagement with inner diameter 46 of housing 14 and is of a length which is substantially equal to the length of housing 14 .
Damping sleeve 18 is provided with a centrally located, longitudinal first bore 54 , located adjacent end 22 and in communication with a longitudinal second bore 58 adjacent end 26 , coaxially aligned with first bore 54 . Preferably, damping sleeve 18 is formed from Ultra High Molecular Weight polyethylene (UHMW) such as that manufactured by the Cadillac Plastic & Chemical Company of Troy, Mich., in the United States. UMHW is presently preferred as it provides a high degree of abrasion resistance and has a relatively low coefficient of friction which provides for a longer life cycle and good vibration damping properties.
First bore 54 has a diameter which is selected to provide minimal clearance or a slight interference around the cylindrical portion of square drive 34 and shaft 30 of pulse wrench 38 and is of a length which allows square drive 34 to pass into the second bore 58 . Second bore 58 is sized to removably receive the cylindrical portion of socket 42 , preferably with a slight interference , and to permit engagement of the socket with the square drive 34 in the conventional manner. The diameter of bores 54 and 58 is preferably such as to produce a slip fit, as earlier defined, between the adaptor and shaft 30 and the adaptor and the socket 42 . As shown in FIG. 1, the diameter of second bore 58 is such that a seat 62 is formed at the junction of first bore 54 and second bore 58 which serves to locate socket 42 when positioned therein. A means to rotationally locate adaptor 10 relative to socket 42 is provided.
In the presently preferred embodiment the means to rotationally locate the adaptor relative to the socket is at least one threaded bore 66 which passes radially through housing 14 and damping sleeve 18 to second bore 58 and is longitudinally positioned to permit a grub screw 70 , or other suitable fastener threaded therein, to enter a bored hole 74 , dimple or retaining groove on socket 42 . It is contemplated that other means of locating adaptor 10 relative to socket 42 may also be employed, such as high strength glue, a key groove cut into socket 42 with a complementary key ridge in bore 58 etc. or any other means which inhibits rotation of the socket relative to the adaptor.
To employ the present invention, socket 42 is pressed through end 26 into bore 58 until it is firmly seated against seat 62 . Grub screw 70 is then screwed through threaded bored hole 74 , until socket 42 is secured in place. Adaptor 10 , disposed over socket 42 is then placed onto pulse wrench 38 by pressing square drive 34 and shaft 30 into end 22 and first bore 54 . Square drive 34 passes through first bore 54 and engages a complementary female connector 78 on the rear face of socket 42 in a conventional manner. A spring retainer 35 , disposed through the surface of square drive 34 , retains socket 42 also in a conventional manner. When fully assembled, the fit between shaft 30 and, first bore 54 provides negligible clearance or preferably a slight interference as does the fit between socket 42 and second bore 58 . Consequently the adaptor 10 surrounds the conventional square drive joint between socket 42 and shaft 30 and minimizes any rotational axis misalignment of these two elements and additionally inhibits rotational motion of the socket 42 relative to shaft 30 .
In operation the damping sleeve 18 serves several purposes. First, as it fits tightly around both shaft 30 and socket 42 axial misalignment is minimized. This reduces vibration of the driver and more torque is transferred to the socket 42 . Second, the tight fit inhibits relative rotational motion between the drive shaft 30 and socket 42 which is particularly important when the driver is an impact or pulse driver. Thirdly, the UHMW material used in sleeve 18 absorbs a portion of any vibration which is created thus reducing any vibration transmitted to the driver and experienced by the operator.
As shown in FIG. 2, when pulse wrench 38 is used in conjunction with a shaft extension 100 , additional vibration reduction can be achieved by using a second anti-vibration adaptor 104 . Shaft extension 100 is of the conventional type and is provided with a square drive connector female end 108 and a square drive connector male end 110 . Adaptor 104 is substantially similar to adaptor 10 , like elements being indicated with primed numerals. In this embodiment, the second bore 58 is sized to accommodate female end 108 and threaded bore 66 is positioned along housing 14 such that grub screw 70 will enter a bored hole 112 , dimple or retainer groove on the female end 108 of shaft extension 100 .
Second bore 58 is sized to create an interference fit when placed over female end 108 with negligible clearance thereby establishing a fixed connection between adaptor 104 and shaft extension 100 . In practice, engagement of adaptor 104 and shaft extension 100 is accomplished by lightly press fitting the components together. This is achieved by pressing second bore 58 of adaptor 104 over female end 108 until in a fully seated position as indicated in FIG. 2 . However it is contemplated that it is possible to size bore 58 with a small clearance or very slight interference and so create a releasable connection between female end 108 and second bore 58 . Provided that any clearance maintains a connection with minimum rotational axis misalignment the anti-vibration characteristics of adaptor 104 will not be unduly compromised.
First bore 54 is sized to receive shaft 30 removably and square drive 34 in a manner substantially identical to the connection of adaptor 10 and pulse wrench 38 of FIG. 1 .
Similarly adaptor 10 and socket 42 mounted therein installs to male end 110 of extension shaft 100 in a manner identical to the installation of the adaptor to pulse wrench 38 , as described with respect to FIG. 1 .
Performance testing of adaptors 10 and 104 was performed using a 12 mm socket, a 6″ extension shaft mounted onto a Uryu UX500 Pulse wrench having a ⅜″ square drive. The socket, extension shaft were all new and the pulse wrench was rebuilt to new conditions. Comparison measurements for torque and vibration were made with this configuration with and without adaptors 10 and 104 . The test was conducted in an automotive production environment, specifically a bumper installation application, in which five fastener run-downs were required per vehicle. Initial torque settings for each pulse wrench were made with a Uryu UET200 torque setting tool. Torque measurements were made prior to installation using a Tonichi torque wrench. Vibration measurements were made at the pulse wrench using a SKF CMVP20 Vibration Check Unit.
The results obtained were as follows. Initial measurements of the pulse wrench were conducted with the torque set at 200 kgf-cm indicated a 32.14% increase in static torque measured on the fastener and a 97.35% decrease in vibration at the tool when adaptors 10 and 104 were used compared to the control case without adaptors 10 and 104 .
After 50,000 fastener run-downs, to determine the effect of wear on the results, measurements conducted with the torque set at 250 kgf-cm indicated a 21% increase in static torque measured on the fastener and a 94.2% decrease in vibration at the tool when adaptors 10 and 104 were used compared to the control case without adaptors 10 and 104 .
These tests were again performed after 225,000 fastener run-downs, with measurements conducted with the torque set at 220 kgf-cm and a 12.5% increase in torque was measured on the fastener and a 95.9% decrease in vibration at the tool was measured when adaptors 10 and 104 were used as compared to the control case without adaptors 10 and 104 . 225,000 run-downs is representative of the full life of adaptors 10 and 104 . These results clearly indicate that significant increases in torque and decreases in vibration experienced by the operator can be achieved when adaptors 10 and 104 are employed.
A similar test was performed using the above-identified equipment but instead using a single adaptor mounted directly on the pulse wrench with no shaft extension in place. The results indicated a 92.35% reduction of vibration at the tool and an increase in fastener torque of 18.2%.
In some situations it has been found advantageous to employ an anti-vibration adaptor which physically mounts to the body of the tool. FIG. 3 shows such a situation in which an anti-vibration adaptor, generally indicated at 204 is directly mounted to a tool 200 which, for example purposes, is illustrated as a right angle tool. However, tool 200 may be any suitable straight nutrunner, multi-head driver or similar tool as previously described. Adaptor 204 , as seen in section in FIG. 4, generally comprises a housing 208 having a pair of ends 212 and 216 , a bearing 220 and a damping means which, in the preferred embodiment comprises a damping sleeve 224 .
Housing 208 is generally cylindrical and annular in cross-section and preferably formed from stainless steel or aluminum although other materials such as the above described with respect to FIG. 1 may be employed. Housing 208 adjacent end 216 is provided with a first bore 228 which is sized to removably engage a body portion 232 of tool 200 , centered about a square drive 234 . Housing 208 is secured to tool 200 using suitable fixing means, such as three grub screws 236 circumferentially spaced 120° apart. Other tool fixing means may be a threaded portion on housing 208 which engages a complementary threaded portion on tool 200 or any other suitable method of fixing adaptor 204 to tool 200 as would occur to those skilled in the art.
A longitudinally oriented second bore 240 is located in a mid portion of housing 208 and is coaxially aligned and in communication with first bore 228 . Second bore 240 is sized to freely accommodate shaft extension 100 which mounts to square drive 234 in the conventional manner.
A longitudinal third bore 244 , is coaxially aligned and in communication with second bore 240 , adjacent end 212 . Third bore 244 is sized to accommodate bearing 220 which abuts a seat 248 formed at the union of second and third bores 240 and 244 respectively. A groove, 252 is provided in the wall of third bore 244 adjacent bearing 220 which receives a snap ring 254 for the purpose of retaining bearing 220 in position.
Damping sleeve 224 is an annular member which is provided with an outer diameter sized for an interference press-fit engagement with the inner diameter of bearing 220 . The outer diameter of damping sleeve 224 includes a shoulder 262 at one end which cannot pass through bearing 220 and a smaller shoulder 261 at the other end which can be forced through bearing 220 . The spacing between shoulders 261 and 262 substantially corresponds to the longitudinal length of the inner diameter of bearing 220 . Damping sleeve 224 is press-fitted into bearing 220 so that shoulders 261 and 262 abut bearing 220 to maintain damping sleeve 224 in place. As with other previously described damping sleeves, damping sleeve 224 is preferably formed from UHMW such as that manufactured by CADCO® which offers a relatively high degree of abrasion resistance and a relatively low coefficient of friction. Damping sleeve 224 has an inner diameter 258 which is sized to fit around shaft extension 100 with negligible clearance.
In operation, female end 108 of extension shaft 100 is fitted to square drive 234 of tool 200 and is retained by a conventional spring pin 235 . Male end 110 of shaft extension 100 is pressed through inner diameter 258 of damping sleeve 224 until first bore 232 slides over and is seated on tool housing 228 . Once seated, grub screws 236 are tightened onto tool 200 to secure adaptor 204 in place.
In addition to adaptor 204 , tool 200 may also preferably employ adaptor 10 at socket 42 . In either case, adaptor 204 reduces the vibration experienced by the tool operator and increased the torque transmitted to shaft 100 in a manner similar to that described above in regard to adaptor 10 .
The present invention has been described with reference to a presently preferred embodiment. Other variations and embodiments of the present invention may be apparent to those of ordinary skill, in the art. It is emphasized ,however, that the adaptor is not a replacement for the conventional driver socket coupling but is employed as an auxiliary device which improves the operation of the coupling. Accordingly, the scope of protection sought for the present invention is only limited as set out in the attached claims. | Power drivers are commonly used in production to tighten fasteners such as nuts and bolts. The socket which engages the fastener is normally coupled to the drive shaft of the power driver by a square male end on the drive shaft and a complementary square female connector on the socket. These components are not produced to close tolerances and as a result there is substantial play permitting misalignment of the rotational axes of the drive shaft and the socket and some rotational freedom between the drive shaft and the socket. In accordance with the invention an anti-vibration adaptor is provided comprising a sleeve containing a cylinder of resilient material which surrounds a portion of the drive shaft and a portion of the socket, including the point of coupling, sufficiently closely to minimize misalignment of the rotational axes of the drive shaft and the socket and reduce rotational freedom. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 11/315,408 (now U.S. Pat. No. 8,402,093), filed on Dec. 22, 2005, the entirety of which is incorporated by reference herein.
BACKGROUND
Email can be accessed and used at the workplace through various software programs and company servers or remotely viasa a web access program. Email accounts on home computers can be accessed through a software program such as MICROSOFT® Office OUTLOOK®, or from a web-access program, such as MICROSOFT® Office OUTLOOK® Web Access (OWA). Present email utilities can contain a feature whereby the user can partially enter an email address and the system automatically completes the entry, based on available data. Problems can arise when a user enters an email address that the system does not recognize.
Current technologies attempt to reconcile ambiguous or unrecognized email addresses by redirecting the user to a different interface. Current processes are cumbersome and can be confusing. Methods for data entry, searches, confirmation, and other conventions used in the interface may vary from that of the email program. In addition, once the process starts, the user must remain in that interface until all ambiguous or questionable email addresses are resolved. The user cannot leave the interface to begin work on the email message until all address ambiguities are resolved.
SUMMARY
Various technologies and techniques are disclosed that improve the process for resolving data elements, such as email addresses. Some or all of these technologies and techniques can improve the speed and ease with which users can complete the resolution process, as well as perform the task within the same context as the rest of the program or activity. The user can remain in the program or activity without needing to move to a different screen. Furthermore, the user can start and stop the process as desired. By way of example and not limitation, the user can compose part or all of an email message before completing the resolution process. Non-limiting examples of this technology can be used to resolve other ambiguities, including those in non-email applications. As one non-limiting example, the process for scheduling rooms could be resolved using the same technology and techniques. These technologies and techniques can be used with other software programs, such as mapping applications, travel guides, or programs that evaluate patient names/data.
This Summary was provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view of a computer system of one implementation.
FIG. 2 is a diagrammatic view of a data element resolution application of one implementation operating on the computer system of FIG. 1 .
FIG. 3 is a high-level process flow diagram for one implementation of the system of FIG. 1 .
FIG. 4 is a process flow diagram for one implementation of the system of FIG. 1 illustrating the stages involved in resolving data elements.
FIG. 5 is a process flow diagram for one implementation of the system of FIG. 1 illustrating the stages involved in resolving data elements based on various status identifiers.
FIG. 6 is a process flow diagram for one implementation of the system of FIG. 1 illustrating the system's stages involved in allowing a user to resume the resolution process later.
FIG. 7 is a process diagram for one implementation of the system of FIG. 1 that illustrating details of FIG. 6 in the stages involved in the resolution process when a user tries to finalize the activity.
FIG. 8 is a simulated screen for one implementation of the system of FIG. 1 that illustrates user options when no match is found for a user-generated email address entry.
FIG. 9 is a simulated screen for one implementation of the system of FIG. 1 that illustrates user options when no exact match is found for a user-generated email address entry.
FIG. 10 is a simulated screen for one implementation of the system of FIG. 1 that illustrates user options when more than one match is found for a user-generated email address entry.
FIG. 11 is a simulated screen for one implementation of the system of FIG. 1 that illustrates user options when a server error is encountered.
DETAILED DESCRIPTION
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles as described herein are contemplated as would normally occur to one skilled in the art.
The system may be described in the general context as an application that improves the workflow process for resolving data elements, such as email addresses, but the system also serves other purposes in addition to these. In one implementation, one or more of the techniques described herein can be implemented as features within an email program such as MICROSOFT® Office OUTLOOK®, MICROSOFT® Office OUTLOOK® Web Access (OWA), AOL Anywhere, or from any other type of program or service that allows creation of email messages. In another implementation, one or more of the techniques described herein are implemented as features with other applications that deal with data elements that need resolved, such as conference rooms, postal addresses, and/or patient data, to name a few non-limiting examples. In one implementation, a user enters a particular data element, such as a plain text name, and the system attempts to resolve that data element to an identifier associated with the particular element, such as an email address. In another implementation, the user enters a particular data element and the system attempts to resolve that data element to make sure it matches something that exists.
As shown in FIG. 1 , an exemplary computer system to use for implementing one or more parts of the system includes a computing device, such as computing device 100 . In its most basic configuration, computing device 100 typically includes at least one processing unit 102 and memory 104 . Depending on the exact configuration and type of computing device, memory 104 may be volatile (such as RAM), non-volatile (such as ROM, flash memory, etc.) or some combination of the two. This most basic configuration is illustrated in FIG. 1 by dashed line 106 .
Additionally, device 100 may also have additional features/functionality. For example, device 100 may also include additional storage (removable and/or non-removable) including, but not limited to, magnetic or optical disks or tape. Such additional storage is illustrated in FIG. 1 by removable storage 108 and non-removable storage 110 . Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Memory 104 , removable storage 108 and non-removable storage 110 are all examples of computer storage media. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by device 100 . Any such computer storage media may be part of device 100 .
Computing device 100 includes one or more communication connections 114 that allow computing device 100 to communicate with one or more servers, such as server with email data store 115 . Computing device 100 may also communicate with one or more computers and/or applications 117 . Device 100 may also have input device(s) 112 such as keyboard, mouse, pen, voice input device, touch input device, etc. Output device(s) 111 such as a display, speakers, printer, etc. may also be included. These devices are well known in the art and need not be discussed at length here.
Turning now to FIG. 2 with continued reference to FIG. 1 , an data element resolution application 200 operating on computing device 100 is illustrated. Data element resolution application 200 is one of the application programs that reside on computing device 100 . Alternatively or additionally, one or more parts of data element resolution application 200 can be part of system memory 104 , on other computers and/or servers 115 , or other such variations as would occur to one in the computer software art.
Data element resolution application 200 includes business logic 204 , which is responsible for carrying out some or all of the techniques described herein. Business logic 204 includes logic for checking data elements entered by the user and determining whether they are unresolved 206 , logic for determining a list of potential data elements for unresolved item(s) 208 , logic for displaying a suggested list of potential data elements in the same context with rest of the application 210 , logic for allowing the user to continue working with the activity and resume the resolution process later 212 , logic for prompting the user with viable options for resolution 214 , and other logic for operating the application 220 . In one implementation, business logic 204 is operable to be called programmatically from another program, such as using a single call to a procedure in business logic 204 .
In one implementation, business logic 204 resides on computing device 100 . However, it will be understood that business logic 204 can alternatively or additionally be embodied as computer-executable instructions on one or more computers and/or in different variations than shown on FIG. 2 . Alternatively or additionally, one or more parts of data element resolution application 200 can be part of system memory 104 , on other computers and/or applications 117 , or other such variations as would occur to one in the computer software art.
The examples presented herein illustrate using these technologies and techniques with an email application in one implementation. However, as discussed previously, in other implementations these technologies and techniques are used with other systems for resolving other types of data elements, such as postal addresses, conference rooms, patient records, etc.
Turning now to FIGS. 3-4 with continued reference to FIGS. 1-2 , the stages for implementing one or more implementations of data element resolution application 200 are described in further detail. FIG. 3 is a high level process flow diagram for data element resolution application 200 . In one form, the process of FIG. 3 is at least partially implemented in the operating logic of computing device 100 .
The procedure begins at start point 240 with analyzing information the user inputs into one or more data element fields (stage 242 ), such as an email address entered into an address field in an email message. The system attempts to retrieve existing information from one or more data stores (stage 244 ). Data stores can include, but are not limited to, databases, files on a local and/or remote computer, and/or other data storage systems. As one non-limiting example, email addresses are retrieved from one or more central data stores of stored information known as “contacts.” Separate data stores can contain global and personal contact information. One example of a data store for global contacts is the email addresses for all employees in a company. Another non-limiting example of contacts is email information that each employee can enter into a personal contacts repository. Such original data sources can be used to obtain information, which can then be used by data element resolution application 200 . In another implementation, data elements are retrieved by data element resolution application 200 when accessed via a web server over the Internet.
The information is analyzed (stage 246 ) and compared to user input. Information regarding potential matches is grouped together appropriately and displayed as a context menu (stage 248 ) within the application. Other types of menus or dialogs that allow the user to remain in the same context in the application and select a particular operation could also be used. The context menu includes one or more options of appropriate action to take to resolve an ambiguous data element (stage 260 ). When the user completes a valid action, resolution for that data element is complete (stage 264 ). The process ends at point 266 .
FIG. 4 illustrates one implementation of a more detailed process for resolving data elements. In one form, the process of FIG. 4 is at least partially implemented in the operating logic of computing device 100 . The procedure begins at start point 280 with the user entering part or all of an address into one or more data element fields (stage 282 ). The user engages the resolution process (stage 284 ), which cues the system to compare the user's entries with data elements stored locally on the computing device 100 or remotely on a server 115 . In one implementation, the resolution process is engaged when the user selects a resolve option, such as upon selecting a check names option.
In another implementation, the resolution process is engaged as the user types an address in the address field. Other variations are also possible for controlling how the user engages the resolution process. The presence of one or more ambiguous data elements causes a context menu to appear within the user's application (stage 286 ). The user reconciles the discrepancy by selecting from a list of close matches or by otherwise resolving the discrepancy (stage 288 ). The selected or keyed name replaces the ambiguous name in the address field (stage 290 ). If more than one data element is ambiguous, the process is repeated (stage 292 ) until all data elements are resolved. Then the user is allowed to finalize the activity, such as send the email, when the resolution process is complete (stage 294 ). The process ends at end point 296 .
FIG. 5 illustrates the stages involved in resolving data elements based on particular status identifiers in one implementation. In one form, the process of FIG. 5 is at least partially implemented in the operating logic of computing device 100 . The user performs an action that activates the address resolution process (stage 321 ). The system recognizes user input into one or more address fields (stage 322 ). The system compares the input to available data stores of data elements (e.g. contacts) (stage 324 ) and determines if the user entry is ambiguous or is an exact match to one address in the data stores (decision point 326 ). If the address is not ambiguous because an exact match is found, the address is displayed in a resolved status (stage 327 ) and the system checks to see if there are any other data elements to resolve (decision point 350 ).
If the address is ambiguous and no exact match is found (decision point 326 ), the system uses business logic 208 to generate a list of potential matches and appropriate actions to take (stage 328 ). The system displays a status message, a list of potential matches, and/or options for appropriate actions in a context menu in the same context as the rest of the application (stage 336 ). If the status is unresolved because no match was found (stage 338 ) the user resolves it by deleting the entry (stage 340 ) or by selecting from a list of potential matches (stage 346 ). If the status is ambiguous because more than one match was found, the user can select from a list of potential matches (stage 346 ). The resolution process is repeated until all data elements are resolved (decision point 350 ). When no more data elements remain to be resolved (decision point 350 ), the process then ends at end point 352 .
FIG. 6 illustrates the process for resuming the resolution process in one implementation in more detail. In one form, the process of FIG. 6 is at least partially implemented in the operating logic of computing device 100 . The process starts at start point 370 when the user selects a data element resolution option (e.g. “Check Names”) (stage 372 ) to check the validity of all data elements entered into data element fields (decision point 374 ). In one implementation, a user enters a particular data element, such as a plain text name, and the system attempts to resolve that data element to an identifier associated with the particular element, such as an email address. In another implementation, the user enters a particular data element and the system attempts to resolve that data element to make sure it matches something that exists. If all data elements are recognized as valid (decision point 374 ), the process ends at end point 376 . If one or more data elements are questionable, or ambiguous, the user will see a context menu (stage 378 ) displaying a list of potential matches and actions to resolve the ambiguity without requiring the user to change context (e.g. without having to go to another screen, etc.).
If the user wishes to continue working with the activity (e.g. email message) (decision point 380 ), they can work with it as desired (stage 381 ). While returning to work with the activity (e.g. email), the user can close the context menu (stage 380 ) by simply clicking elsewhere in the activity or message, by pressing a designated key or keys (such as Esc), and/or by other methods that cause the context menu to lose focus. The user can return to the context menu any time before attempting to finalize the activity, such as send the email. The resolution process can be resumed later by selecting the unresolved address in a particular fashion (e.g. right-click or other selection) to resolve the potential list of matches (stage 382 ).
If the user does not wish to exit the resolution process to continue working with the activity (decision point 380 ), or if the user stops and then resumes the resolution process (stage 382 ), the user then selects a desired address from the list of potential matches and actions (stage 384 ).
In one implementation, ambiguous data elements are differentiated from valid data elements by appearing on-screen in a different color and/or by appearing with a dashed underline instead of a solid underline. When the data element is resolved, the user will either be allowed to finalize the activity (e.g. send the email) or resolve the next ambiguous data element (if more than one is present). A new context menu with potential matches and actions will appear in turn for each ambiguous data element. When all data elements are resolved (decision point 386 ), the process ends at end point 388 .
FIG. 7 is a flow diagram for one implementation that illustrates what happens when a user attempts to finalize an activity, such as by attempting to send an email message. In one form, the process of FIG. 7 is at least partially implemented in the operating logic of computing device 100 . FIG. 7 begins at start point 400 with the user selecting an option that instructs the system that the user wishes to finalize the activity (e.g. send an email). The system checks all data elements for ambiguity and resolution status (stage 412 ). The system then displays a context menu consisting of a status message and/or a list of actions that may be taken. Options for actions vary according to whether the system encountered an error in the process, whether the system found no match, one or more partial matches, or more than one exact match.
In one implementation, the system does not check elements until the user activates that feature, such as by selecting a “check names” option. In another implementation, the system checks elements automatically at a pre-determined point in time, such as when the user exits the data element field (e.g. the address field). When the system checks an element and it matches a unique address in the data store, then the address name is considered resolved (stage 436 ). If a checked element cannot be matched to a data element in the data store (stage 418 ), the user must delete that name from the address field or reenter the name (stage 420 ). If one or more partial matches are found (stage 422 ), or if more than one exact match is found (stage 430 ), then the user can select the correct data element from a list that appears in the context menu ( 424 ). If a network or server error (stage 432 ) occurs during the checking process, then the user is instructed to try again (stage 434 ). The process may repeat itself (stage 426 ) as needed. The process ends at end point 428 when all data elements have been resolved. It will be appreciated that some, all, or additional stages than as listed in the figures herein could be used in alternate embodiments, and/or in a different order than as described.
Turning now to FIGS. 8-11 , simulated screens are shown to illustrate a user interface that allows a user to view and interact with an email resolution context menu created using data element resolution application 200 . These screens can be displayed to users on output device(s) 111 . Furthermore, these screens can receive input from users from input device(s) 112 .
When the user selects the data element resolution option (e.g. “Check Names”) (stage 372 ), the system analyzes all entered data elements against existing data store(s) (stage 324 ). The results of the analysis appear as a context menu. The information in the context menu can differ, as depicted in FIGS. 8-11 . FIG. 8 shows a simulated screen 500 that appears in one implementation when the resolution process cannot find a match for an ambiguous data element 510 . The context menu 520 displays one option given for resolving such an address, that is, to remove it without sending the email 530 . Clicking on this option deletes the ambiguous address from the address field indicated. Then the user can re-enter an address or send the email.
FIG. 9 shows a simulated screen 600 of one implementation that appears when the resolution process finds no exact match, but finds partial or potential matches. The context menu 620 displays all potential matches that the user can select from 630 , plus the option of removing the data element 640 . If the user clicks on an address in the context menu, it replaces the ambiguous address 610 .
FIG. 10 shows a simulated screen 660 of one implementation that appears when the resolution process finds more than one exact match for an ambiguous data element 670 . The context menu 680 lists potential matches is seen in 690 . If the user clicks on an address in the context menu, it replaces the ambiguous address 670 . As in all other context menus, the option for removing the data element is listed 695 .
FIG. 11 shows a simulated screen 700 of one implementation that appears when a server error occurs. In the event that a system error prevents the analysis of a potential match, the user's options are to close the context menu 720 and try again 730 when system integrity is restored, or to delete the address without sending the email ( 740 ). In these simulated screens illustrated in FIGS. 8-11 , the resolution context menu is shown within the same context as the rest of the email application, thereby allowing the user to fix the problem without having to go through one or more other screens and/or lose the ability to keep working with the email and resume the resolution process later.
Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. All equivalents, changes, and modifications that come within the spirit of the implementations as described herein and/or by the following claims are desired to be protected.
For example, a person of ordinary skill in the computer software art will recognize that the client and/or server arrangements, user interface screen content, and/or data layouts as described in the examples discussed herein could be organized differently on one or more computers to include fewer or additional options or features than as portrayed in the examples. | Various technologies and techniques are disclosed that improve the workflow process for resolving data elements, such as email addresses. These technologies and techniques allow the user to perform such tasks in the same context as the activity or message. In addition, user can start and stop the resolution process at any point in the process of composing the activity or email. The activity cannot be finalized, such as an email message being sent, until all of the data elements are resolved. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/246,296, filed Sep. 28, 2009, U.S. Provisional Application No. 61/246,297, filed Sep. 28, 2009, and U.S. Provisional Application No. 61/246,304, filed Sep. 28, 2009.
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates generally to lamps and light bulbs for lamps. More particularly, the present invention is directed to an indoor/outdoor lamp, which may be battery powered. Additional aspects of the present invention relate to an LED-based light bulb.
[0005] 2. Description of the Related Art
[0006] Lamps are widely used to provide light to dark areas. Lamps typically include a base for placing the lamp on a support surface, such as the floor or table. Most lamps further include a lamp body extending from the base, wherein the lamp body comprises a socket configured to receive a light bulb. In general, lamps include a power cord to receive power from an external power source, such as an electrical outlet on a wall, to light up a light bulb connected to the socket.
[0007] In addition to serving the basic utilitarian need of providing light, lamps may also be designed to be aesthetically appealing. For instance, the lamp base and lamp body may define aesthetically pleasing sizes, shapes and colors. Furthermore, the lamp shades may also contribute to the overall aesthetic appeal of the lamp.
[0008] Lamp usage is typically limited to indoor usage for a variety of reasons. One reason is that lamps generally are not configured to withstand the elements which may be encountered during outdoor use. For instance, precipitation may damage the body/base of the lamp, as well as the lamp shade. Precipitation may also create wetness, which may cause an electrical shortage in the wiring of the lamp. Wind may also present a problem for outdoor lamp usage, as a gust of wind may cause the lamp to fall over, resulting in possible damage to the lamp.
[0009] Another reason that lamps are typically limited to indoor use is that operation of the lamp is generally dependent upon power from an external power source. In this regard, indoor lamp usage allows a lamp to receive power from a power outlet disposed in a wall via a power chord. For instance, most indoor lamps operate on 120 VAC, which poses a life threatening shock hazard, especially in wet outdoor locations. Furthermore, the power chord may be a tripping hazard. Accordingly, usage of a lamp in a remote outdoor location is typically unattainable because of the dependency of power from external power sources.
[0010] In addition to the above-described deficiencies associated with the lamps, conventional light bulbs used with the lamps also suffer from their own deficiencies. Incandescent light bulbs are traditionally used in light fixtures and lamps, and operate by passing an electric current through a thin filament, heating it to a temperature which produces light. Incandescent light bulbs provide a sufficient amount of light, yet they tend to be inefficient from an energy standpoint and may undesirably emit large amounts of heat. Indeed, in the United States, laws have been drafted to encourage phasing out of incandescent light bulbs.
[0011] The present disclosure addresses and overcomes the above-noted deficiencies by providing a battery powered lamp sized and configured for indoor and outdoor usage. The present disclosure further relates to an improved light emitting diode (LED) based light bulb which is more efficient than conventional incandescent light bulbs. These and other advantages attendant to the present invention will be described in more detail below.
BRIEF SUMMARY OF THE INVENTION
[0012] In accordance with the present invention, there is provided a decorative table/floor lamp configured for both indoor use and outdoor use. The lamp may include several features to protect against conditions encountered during outdoor use, such as wind, precipitation, lack of external power, etc. The lamp also defines an aesthetically pleasing design to provide lighting during upscale outdoor events/celebrations, such as weddings, reunions, holiday events, a private gathering in a backyard, or in wet areas, such as by a pool, ocean or lake. In this regard, the decorative table/floor lamp is a decorative alternative to conventional propane powered lanterns, or candles, which were commonly used to provide lighting outside.
[0013] According to one embodiment, the lamp includes a lamp body and a lamp base coupled to the lamp body. The lamp base includes a base housing defining an inner cavity. A battery is disposed within the inner cavity to power the lamp so the lamp is not dependent upon power from external resources. The lamp base is sized and configured to mitigate pivotal movement of the lamp relative to the supper surface (i.e., tipping) in wind up to 30 MPH.
[0014] According to another implementation of the present invention, there is also provided a light emitting diode (LED) based light bulb including a unitary light structure having a base and a stem extending from the base. The stem is mounted with a plurality of light emitting diodes operative to produce a color temperature of between 2,700 to 3,000 K. The LED-based light bulb is a desirable alternative to conventional incandescent light bulbs because it provides greater illumination and utilizes less power than prior art light bulbs. Furthermore, the LED-based light bulb is rated for outdoor use making it desirable for use with the above-described lamp.
[0015] The present invention is best understood by reference to the following detailed description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These, as well as other features of the present invention, will become more apparent upon reference to the drawings wherein:
[0017] FIG. 1 is a upper perspective view of a lamp constructed in accordance with an embodiment of the present invention;
[0018] FIG. 2 is an upper perspective sectional view of the lamp depicted in FIG. 1 ;
[0019] FIG. 3 is an exploded view of the lamp depicted in FIGS. 1 and 2 ;
[0020] FIG. 4 is a side sectional view of the lamp depicted in FIGS. 1-3 ; and
[0021] FIG. 5 is an upper perspective exploded view of an LED-based light bulb constructed in accordance with an embodiment of the present invention.
[0022] Common reference numerals are used throughout the drawings and detailed description to indicate like elements.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Referring now to the drawings wherein the showings are for the purposes of illustrating a preferred embodiment of the present invention only, and not for purposes of limiting the same, FIGS. 1-4 depict a lamp 10 constructed in accordance with an embodiment of the present invention. The lamp 10 is specifically configured for both indoor and outdoor use. In this regard, the lamp 10 is constructed to withstand and endure exposure to the outer elements, while at the same time having an aesthetically appealing design. Furthermore, there is also provided an LED (light emitting diode) based light bulb 110 , which provides greater illumination and utilizes less power than conventional incandescent light bulbs.
[0024] As will be described in more detail below, the lamp 10 includes several features which enable use both inside and outside. One feature relates to a weighted base 12 or lower portion of the lamp 10 which allows the lamp 10 to withstand gusts of wind. Another feature relates to the battery(s) 15 , 17 (see FIG. 4 ) which powers the lamp 10 and allows the lamp 10 to be used in remote outdoor locations which may not have access to other power sources. The lamp 10 also includes a water resistant cavity 16 (see FIGS. 2 and 4 ) within which the batteries 15 , 17 is stored. A 12 volt E26 socket LED based light bulb 110 may be used with the lamp 10 to operate at higher efficiency (i.e., requires less power to enable longer use before the batteries 15 , 17 requires recharging). The lamp 10 may further include a weather resistant coating to protect the lamp 10 from precipitation and to endure temperature extremes (extremely hot temperatures as well as extremely cold temperatures). The lamp shade 18 may also be formed from a weather resistant material to allow the lamp shade 18 to withstand the elements outside.
[0025] The lamp 10 includes a lamp body 20 and a lamp base 12 connected to the lamp body 20 . The lamp base 12 defines an upper end portion 22 and an opposing lower end portion 24 . The upper end portion 22 is disposed adjacent the lamp body 20 and the lower end portion 24 is disposed on a support surface, such as a table, floor or the like. The lamp base 12 includes a base wall 26 defining a base cavity 16 sized to receive the batteries 15 , 17 and related components, as described in more detail below. The lamp base 28 is connected to the base wall 26 to contain the components housed therein. On the underside of the lamp base is a cover that when removed provides access to the base cavity 16 (i.e., to access the batteries 15 , 17 ). The lamp base 28 may be weighted and formed from a dense material to mitigate tipping or falling of the lamp 10 . It is understood that when the lamp 10 is placed outside during use, it is subject to the weather conditions, including wind. Therefore, the weighted lamp base 28 may allow the lamp to withstand gusts of wind up to 30 MPH without tipping or falling from a generally horizontal surface. Although the lamp base 28 is weighted to mitigate tipping of the lamp, the overall weight of the lamp 10 is light enough to enable carrying of the lamp by a single individual.
[0026] In addition to a weighted lamp base 28 , the configuration of the base wall 26 may also mitigate tipping of the lamp 10 . In the specific configuration depicted in the figures, the base wall 26 defines a generally frustoconical shape, wherein the lamp base 12 defines a diameter that increases from the upper end portion 22 toward the lower end portion 24 . The increased diameter of the lower end portion 24 reduces the tendency that the lamp 10 will tip in a gust of wind.
[0027] It is contemplated that other embodiments of the lamp 10 may include a lamp base 12 that does not define a frustoconical shape without departing from the spirit and scope of the present invention. Along these lines, the lamp base 12 preferably defines a shape that is wider adjacent the lower end portion 24 than the upper end portion 22 . Lamp base configurations which deviate from such a shape may include weights disposed within the base cavity 16 adjacent the lower end portion 24 to compensate for a shape which may not mitigate tipping.
[0028] The lamp body 20 includes an aesthetically pleasing design that may compliment the design of the lamp base 12 . In the embodiment depicted in the drawings, the lamp body 20 includes a body wall 30 (see FIGS. 2 and 4 ) defining a frustoconical lower portion 32 (see FIGS. 2 and 4 ) and an inverted frustoconincal upper portion 34 (see FIGS. 2 and 4 ). The lower end of the frustoconical lower portion 32 is complimentary to the lamp base 12 to give the appearance of a seamless transition between the lamp base 12 and the lamp body 20 .
[0029] The lamp body 20 includes a body cavity 36 (see FIGS. 2 and 4 ) including an inner lamp conduit 38 extending therethrough. Wiring may extend through the conduit 38 between the batteries 15 , 17 and the lamp socket 40 (see FIGS. 2 and 4 ) to transfer power to the light bulb 110 . In this regard, the conduit 38 includes a hollow passage 42 (see FIGS. 2 and 4 ) which contains the wiring.
[0030] The conduit 38 may also interconnect the lamp base 12 to the lamp body 20 . The lamp base 12 includes a base conduit opening disposed adjacent the upper end portion 22 thereof, while the lamp body 20 includes a lower body conduit opening disposed adjacent the lower end portion thereof. The base conduit opening and the lower body conduit opening are coaxially aligned with each other to allow the conduit 38 to extend therethrough and into the base cavity 16 . The end of the conduit extending into the base cavity 16 may include a threaded portion to allow the conduit 38 to engage with a mechanical fastener, such as a nut, to secure the lamp base 12 to the lamp body 20 .
[0031] The lamp 10 may further include a band 46 or strip disposed between the lamp base 12 and lamp body 20 to add to the overall aesthetic appeal to the lamp 10 . The band 46 may conceal the joint between the lamp base 12 and the lamp body 20 to create the appearance of a uniform structure. In certain embodiments, the band 46 may also provide a water resistant barrier between the lamp base 12 and lamp body 20 to protect against moisture seeping into the base cavity 16 or body cavity 36 through the base conduit opening or lower body conduit opening. To this end, the band 46 may be formed from aluminum or other materials known in the lamp industries connected with silicone or rubber gaskets to create a water resistant barrier. The band 46 may be compressed between the lamp body 20 and lamp base 12 when the nut 44 is tightened onto the conduit 38 .
[0032] Referring now to FIGS. 2-4 , a lamp stem 48 may extend between the lamp body 20 and the lamp shade 18 . As shown in the drawings, an upper end cap 50 is disposed at the upper end portion of the lamp body 20 . The upper end cap 50 may be configured to be theadably engageable or frictionally engageable with the lamp stem 48 to secure the lamp stem 48 to the lamp body 20 . The upper end cap 50 includes an opening which the conduit 38 extends through. The lamp stem 48 is hollow to allow the wiring to continue from the conduit 38 through the lamp stem 48 .
[0033] A socket 40 is connected to the lamp stem 48 opposite the lamp body 20 . The socket 40 may include a standard connector for mating with a light bulb 110 . The wiring from the batteries 15 , 17 extends to the socket 40 to provide power to the socket 40 , and ultimately, to the light bulb 110 engaged with the socket 40 . A socket protector or rubber boot may be connected to the socket 40 for keeping the socket fluid tight.
[0034] As previously mentioned, one embodiment of the lamp 10 include a batteries 15 , 17 to allow the lamp 10 to be operational in a location remote from an external power source. The batteries 15 , 17 may be wired in parallel to give the lamp a longer lamp life. The batteries 15 , 17 are disposed within the lamp base cavity 16 to provide easy access to the batteries 15 , 17 , and to add to the weight of the base 12 of the lamp 10 to further mitigate tipping of the lamp 10 . A battery bracket 14 may be used to secure the batteries 15 , 17 within the base 12 . The batteries 15 , 17 are preferably rechargeable 12V batteries, although other batteries known in the art may also be used without departing from the spirit and scope of the present invention. The batteries 15 , 17 may be in electrical communication with a charging plug 52 disposed within the base wall 26 to allow a user to connect a recharging cable to the batteries 15 , 17 . The recharging cable may be connected to a wall outlet, or other power source, to recharge the batteries 15 , 17 . A waterproof rubber cap may be disposed about the charging plug 52 to create a fluid tight seal between the charging plug 52 and the base wall 26 .
[0035] The lamp base 12 may include a battery support for supporting the batteries 15 , 17 within the lamp base 12 . In addition to providing a structural support to the batteries 15 , 17 , the battery support may be configured to provide ventilation to the batteries 15 , 17 , as well as insulate the batteries 15 , 17 from extreme heat or cold. One embodiment of the battery support includes a layer of insulating foam disposed between an upper grill and a lower grill to provide ventilation. The above-described battery support is exemplary in nature only; it is understood that other battery supports may be used without departing from the spirit and scope of the present invention.
[0036] By disposing the batteries 15 , 17 within the water resistant cavity 16 , the batteries 15 , 17 is protected from wetness from precipitation. In this regard, the lamp 10 may be disposed outside without worry that a surprise storm may damage the batteries 15 , 17 . Furthermore, the batteries 15 , 17 allows the lamp 10 to be used in remote areas where other external power sources are not readily available, such as at a beach, on a mountain, on a boat, or even a remote area of the user's property.
[0037] The lamp 10 may include circuitry (i.e., a circuit board) for controlling the brightness of the light emitted by the lamp 10 . For instance, the lamp 10 may have several dimming settings, such as high, medium, and low, to provide light at different brightness levels. The circuitry may additionally be configured to automatically turn off the lamp 10 when the power in the batteries 15 , 17 is low.
[0038] As an alternative to a battery powered lamp, the lamp 10 may include a power cord which plugs into an external power source, such as an outlet on a wall. It is contemplated that such a lamp 10 may be used inside, or on a deck, porch, or patio, where a wall outlet is readily accessible. The cord is preferably 8-10 feet in length; however, those skilled in the art will appreciate that the cord may define other lengths. The cord is additionally outdoor rated to endure long exposure outside.
[0039] Various components of the lamp 10 may be coated with one or more coatings to mitigate damage caused by extensive use outside. Along these lines, the external surfaces of the lamp 10 may be coated with a primer for corrosive resistance. Urethane paint is then applied to the surfaces, in addition to a sealer to provide further protection for outdoor use. The paint is preferably a polyurethane low voc paint.
[0040] A lamp shade 18 may be connected to the lamp body 20 to soften the light emitted thereby. The lamp shade 18 includes shade body 54 and a harp 56 connected the shade body 54 and the lamp body 20 . The shade body 54 is preferably formed from an outdoor rated fabric to enable the lamp shade 18 to withstand the outside environment. The harp 56 is preferably powder coated to configure the harp 56 for outside use. In a preferred embodiment, the lamp shade 18 includes a UV clear plastic lining with a laminated outdoor rated weather resistant UV rated fabric that diffuses the light from the sides of the lamp shade 18 . The adhesive/glue that seals the plastic to the lamp shade 18 is weather resistant. The harp 56 is plated with a top coat of polyurethane or powder coated to protect against the weather.
[0041] The shade body 54 may define a variety of shapes and sizes. In the embodiment depicted in the figures, the shade body 54 is generally cylindrical in nature; although it is understood that the depicted shade body 54 is exemplary in nature only, and the present invention is not limited thereto. A perforated, stainless steel diffuser 58 may be disposed adjacent an upper end portion of the shade body 54 . The diffuser 58 is preferably formed from aluminum and is plated with a top coat of polyurethane, or powder coated to protect the diffuser 58 from the outer elements, while still allowing diffused light.
[0042] A light bulb 110 is connected to the socket 40 to receive power from the lamp 10 to illuminate the adjacent areas. According to one embodiment, and referring now specifically to FIG. 5 , the light bulb 110 is an improved LED-based light bulb that can be utilized in indoor and outdoor applications and is operative to fit via conventional light sockets 40 . The improved LED-based light bulb 110 provides greater illumination and utilizes less power than conventional incandescent light bulbs. It is recommended that the LED-based light bulb 110 be used with the lamp 10 described above; however, those skilled in the art will appreciate that other light bulbs may be used without departing from the spirit and scope of the present invention.
[0043] Generally, the properties of the improved LED-based light bulb 110 are generally as follows: approximately 8 watt, 12 volt, outdoor rated LED light bulb with lamp base med (E26) socket—color: warm light (2700-3000 Kelvin temp). According to one implementation, the color rendering for the lamp is above 80 CRI. The specifications further include a vertical mounting configuration, inside a diffused shroud to imitate an incandescent light bulb equivalent to approximately 55-60 watts of light. The foregoing specifications are exemplary in nature only and are not intended to limit the scope of the LED-based light bulb 110 .
[0044] The LED-based light bulb 110 includes a base 112 and a stem 114 coupled to the base 112 . A plurality of LEDs 116 are mounted to the stem 114 in spaced relation to each other. In the embodiment depicted in FIG. 5 , the stem 114 includes a plurality of longitudinal faces 118 and an end face 120 , with LEDs 116 mounted to each longitudinal face 118 and the end face 120 to provide illumination in several directions.
[0045] The depicted stem 114 defines a hexagonal transverse cross-section, thereby defining six longitudinal faces 118 . However, those skilled in the art will appreciate that fewer than six or more than six longitudinal faces 118 may be defined by the stem 114 without departing from the spirit and scope of the present invention. In fact, the stem 114 may define various shapes and sizes, such as spherical, semi-spherical, frustoconical, cubical, etc. without departing from the spirit and scope of the present invention.
[0046] The number of LEDs 116 mounted to the stem 114 may also be varied. Fewer LEDs 116 may be mounted for soft or dim lighting applications, while more LEDs 116 may be mounted for brighter applications. However, the stem preferably includes 120 LEDs 116 mounted thereto.
[0047] The stem 114 is configured to be received within a cavity 122 formed within the base 112 . Along these lines, a flange 124 may extend radially outward from the stem 114 to engage with the base 112 to secure the stem 114 thereto.
[0048] The base 112 may be connected to an electrical connector 126 sized to be threadably engageable with a conventional electrical socket. Wiring may extend between the electrical connector 126 and the LEDs 116 to electrically communicate power from the electrical connector to the LEDs 116 .
[0049] An enclosure element 128 , such as a glass, plastic, or polycarbonate globe, may be connected to the base 112 to enclose the stem 114 and LEDs 116 . The size and shape of the enclosure element 128 may vary according to the size and shape of the stem 114 . Furthermore, the enclosure element 128 may be formed in various colors to alter the color emitted by the lamp.
[0050] The LED-based light bulb 110 provides a desirable alternative to conventional incandescent light bulbs because it provides greater illumination and utilizes less power than prior art light bulbs. Along these lines, the light bulb 110 is approximately an 8 watt light bulb which gives approximately 540 lumen output (which is equivalent to 55-60 watts of light) of “reading light” at night, which is unique for a “decorative outdoor portable” fixture. Furthermore, the LED-based light bulb 110 is rated for outdoor use making it desirable for use with the above-described lamp 10 .
[0051] This disclosure provides an exemplary embodiment of the present invention. The scope of the present invention is not limited by this exemplary embodiment. Numerous variations, whether explicitly provided for by the specification or implied by the specification, such as variations in structure, dimension, type of material and manufacturing process may be implemented by one of skill in the art in view of this disclosure. | Provided is a lamp configured for both indoor use and outdoor use. The lamp may include several features to protect against conditions encountered during outdoor use, such as wind, precipitation, lack of external power, etc. The lamp also defines an aesthetically pleasing design to provide lighting during upscale outdoor events/celebrations, such as weddings, reunions, holiday events, or a private gathering in a backyard. The functional and aesthetic features of the lamp, such as the lamp's capability of operating independent of a power cord while at the same time defining a stylish appearance, may additionally make the lamp desirable for use in indoor environments. | 5 |
TECHNICAL FIELD
[0001] The present invention relates generally to computers and more particularly toward optimizing application interactions.
BACKGROUND
[0002] Individuals designing and architecting systems typically utilize a variety of tools, each designed for a particular purpose. Although conventional integrated development environments have gone a long way toward integrating a variety of tools that deal with part of the process, sometimes there are other tools that are needed that are not part of the integrated development environment. This makes it difficult and confusing for users as they must try and understand a plurality of different programming implementations.
[0003] For example, the organization of an enterprise development project enables team members to communicate meaningful information about the state of a project's progress. It also provides a system of grouping software artifacts in some logical fashion. The problem is that the project classification hierarchy can vary from company to company, and in many instances between project types within a single company. Thus, each tool maintains its own common store and individual mechanism of classification. The individual classification mechanisms and structures lead to user confusion due at least in part to the fact that they must understand the inner workings of many classification mechanisms.
[0004] Accordingly, there is a need in the art for a common classification system that allows a consistent set of structures across unrelated tools to facilitate a cohesive user experience.
SUMMARY
[0005] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.
[0006] The present invention concerns a distributed object classification system and method. In particular, the invention provides a loosely-coupled way for unrelated tools to categorized elements they control according to a common, centrally-managed classification scheme. According to an aspect of the subject invention, the classification system also includes mechanisms for storing and retrieving classifying structures. For instance, structures can be instantiated by conforming to a structure type including such things as a node type, a structure type class, and structural constraints. In the end, users of tools employing the present classification system see a single consistent set of structures and enumerations across those tools thereby providing a foundation for a cohesive user experience.
[0007] Common classification of software and software related artifacts is vital to enabling an integrated experience over a federated suit of tools. The distributed classification of the subject invention is an innovative mechanism for achieving such common classification with minimal obligation on the owners of classifiable artifacts.
[0008] More specifically and in accordance with an aspect of the invention, mechanisms for building and maintaining one or more taxonomies are provided. To that end, a graphical user interface and associated APIs (Application Programming Interfaces) can be employed. For example, a user interface can be attached to a tool user interface or utilized separately to classify artifacts by dragging and dropping artifacts onto a classification node. Furthermore another interface helper component can by utilized to facilitate selection of a structure and/or classification nodes provided therein. According to another aspect of the invention, taxonomies can be defined automatically or semi-automatically by employing heuristics and statistical analysis associated with artificial intelligence.
[0009] According to yet another aspect of the present invention, a notification system is provided. The notification system can raise events to owners of classifiable artifacts, the consumers of the common classification structure, when charges are made or proposed. For instance, a before event can be raised to notify owners and give them an opportunity to review the change and either approve the change or veto the proposed change. Alternatively, an after change event can be raised to all customers to enable them to reflect that a change has been completed.
[0010] The distributed classification system and method of the subject invention provides a multitude of advantages. For instance, users have a single place to go to maintain common data structures like their project classifications. Additionally, any common data that can be expressed as a hierarchy or list can be maintained through one common mechanism.
[0011] To the accomplishment of the foregoing and related ends, certain illustrative aspects of the invention are described herein in connection with the following description and the annexed drawings. These aspects are indicative of various ways in which the invention may be practiced, all of which are intended to be covered by the present invention. Other advantages and novel features of the invention may become apparent from the following detailed description of the invention when considered in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The foregoing and other aspects of the invention will become apparent from the following detailed description and the appended drawings described in brief hereinafter.
[0013] FIG. 1 is a schematic block diagram of an distributed object classification system in accordance with an aspect of the present invention.
[0014] FIG. 2 is a schematic block diagram of a structure component in accordance with an aspect of the present invention.
[0015] FIG. 3 is a schematic block diagram of an exemplary classification meta model in accordance with an aspect of the subject invention.
[0016] FIG. 4 is a diagram of a portion of an exemplary project hierarchy in accordance with an aspect of the subject invention.
[0017] FIG. 5 is a diagram of a portion of an exemplary project hierarchy in accordance with an aspect of the subject invention.
[0018] FIG. 6 a is an exemplary instance diagram in accordance with an aspect of the subject invention.
[0019] FIG. 6 b is an exemplary instance diagram in accordance with an aspect of the present invention.
[0020] FIG. 7 is an exemplary instance diagram in accordance with an aspect of the subject invention.
[0021] FIG. 8 is an exemplary instance diagram in accordance with an aspect of the present invention.
[0022] FIG. 9 is an exemplary instance diagram in accordance with an aspect of the subject invention.
[0023] FIG. 10 is an exemplary structural hierarchy in accordance with an aspect of the present invention.
[0024] FIG. 11 is an exemplary graphical user interface in accordance with an aspect of the present invention.
[0025] FIG. 12 is an exemplary graphical user interface in accordance with an aspect of the subject invention.
[0026] FIG. 13 is an exemplary graphical user interface in accordance with an aspect of the present invention.
[0027] FIG. 14 is a schematic block diagram of an event monitoring system in accordance with an aspect of the present invention.
[0028] FIG. 15 is a schematic block diagram of a notification system in accordance with an aspect of the subject invention.
[0029] FIG. 16 is a flow chart diagram of a common classification methodology in accordance with an aspect of the subject invention.
[0030] FIG. 17 is a flow chart diagram of a common enterprise classification scheme methodology in accordance with an aspect of the present invention.
[0031] FIG. 18 is a schematic block diagram illustrating a suitable operating environment in accordance with an aspect of the present invention.
[0032] FIG. 19 is a schematic block diagram of a sample-computing environment with which the present invention can interact.
DETAILED DESCRIPTION
[0033] The present invention is now described with reference to the annexed drawings, wherein like numerals refer to like elements throughout. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed. Rather, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention.
[0034] As used in this application, the terms “component” and “system” are intended to refer to a computer-related entity, either hardware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a server and the server can be a component. One or more components may reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers.
[0035] Furthermore, the present invention may be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques to produce software, firmware, hardware, or any combination thereof. The term “article of manufacture” (or alternatively, “computer program product”) as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. For example, a computer readable media can include but are not limited to magnetic storage devices (e.g., hard disk, floppy disk, magnetic strips . . . ), optical disks (e.g., compact disk (CD), digital versatile disk (DVD) . . . ), smart cards, and flash memory devices (e.g., card, stick). Of course, those skilled in the art will recognize many modifications may be made to this configuration without departing from the scope or spirit of the subject invention.
Classification System
[0036] Turning initially to FIG. 1 , a distributed object classification system 100 is depicted in accordance with an aspect of the subject invention. Classification system 100 comprises classification component 110 , software component(s) 120 , and structure component(s) 130 . Classification component 110 receives or retrieves software component(s) 120 . Software components(s) 120 can be any type of classifiable software artifact or persisted data worth keeping tabs on (e.g., file, object, image . . . ). Upon receipt of one or more software component(s) 120 , the classification component generates and/or places software component(s) 120 into one or more structure component(s) 130 . Classification component 110 can classify software component(s) 120 into structure component(s) 130 utilizing one or more or a combination of distinct mechanisms or methodologies. For example, software component(s) can be classified at the direction of a user employing graphical user interface. Additionally or alternatively, software components(s) can be classified automatically or semi-automatically utilizing a rule based expert system or other artificial intelligence technologies including but not limited to neural and Bayesian networks, and the like. Such classification can be based on a file name, type, and/or content to name but a few. Classification component(s) store software component(s) 120 in any reasonably organized fashion, however according to one aspect of the invention they are organized hierarchically.
[0037] Furthermore and in accordance with another aspect of the present invention, software component(s) 120 are commonly classified for use between and amongst a plurality of federated components. For instance, an enterprise development project includes a collection of tasks to be completed over time that results in the production of a set of software artifacts or components. The organization of an enterprise development project enables team members to communicate meaningfully about the state of a projects progress. It also provides a system of grouping software artifacts in some logical fashion. One significant problem is that this project classification hierarchy can vary from company to company and in many cases between project types within a company. Thus, enterprise customers require a flexible way to represent their common mental model for organizing their projects.
[0038] Because project classification hierarchies are so central to the organization of project artifacts, they should be shared by multiple tools. Without a common way to store and maintain this structure, each tool would be required to have its own mechanism of classification. Without sophisticated multi-way synchronization techniques, the various classification hierarchies would diverge leading to user confusion and a total lack of cohesion. Providing a common structure enables software component classification in a single place. However, not only do multiple artifacts share the same hierarchy, there are alternative structures that might apply to a single artifact. Take, for instance, a work item. It might be classified by a feature area, a breakdown that usually begins with some high-level organization and eventually is refined into broad components and groups of features. In one conventional application, this is the principal method of classification for bugs. Additionally, though, a user might want to assign some temporal classification to a work item.
[0039] The above description illustrates a more general characteristic of the present invention, namely it can be employed as a query point and maintain any hierarchical data that is common across a plurality of services and tools. If, for instance, a tool had a need to associate its artifacts to people in an organizational chart, the present invention could be utilized to hold and provide access to that organizational chart. Likewise, in defect tracking one might determine that they wish to allow users to change the names of various work items (e.g., an IT group in a marketing firm might want to change “defect” to “opportunity”). The present invention allows such customizations to be made easily.
[0040] Additionally, it is not true that all tools share the same classification schemes. For instance, while defect tracking, requirements management, and test case management may all use the same hierarchy, the source control system's classification scheme revolves around folder hierarchies and is under direct control of the source control system. While these two classification schemes may be similar, it is unreasonable to force them to be the same. However, that does not mean that various tools will not want to explore both hierarchies using the same services. For at least that reason, the present invention can include a provider model to enable external parties (e.g., source control) to expose their classification data.
[0041] Turning to FIG. 2 , a structure component 130 is illustrated in accordance with an aspect of the subject invention. Each structure component 130 can be of a particular type 200 . Structure type component 200 or structure section, describes the pattern to which instances of nodes should conform. To that end, structure type component 200 includes node type 210 , structure type class 220 , and structural constraints 230 . A node type 210 defines the kind of thing that can be included in a structure. For instance, a structure based on organizations might consist of a set of Divisions, Groups, Teams, and People. It's likely that one would want to carry different information about a Division (e.g., a division id) than about a Group, Team, or Person. Likewise, one might want to put some constraints on division that may not hold true for team. For example, one might not be able to divide a Division into sub-divisions. Instead, by definition, a Division divides into Groups. However, a Department might be decomposable into sub-departments. Each of the aforementioned distinctions, namely Division, Group, Team, and Person, can be a node type.
[0042] A structure type class 220 describes how a set of nodes of various node types can be assembled into a list or hierarchy. In the preceding example, for instance, one can imagine a kind of structure named “Organization Breakdown” that describes the rules for defining a hierarchy. One can further imagine that in a structure of that type the following statements should be true:
The top nodes in the structure should be Division. Divisions may have both People and Groups as children. Groups may have both People and Departments as children. Departments may have both Teams and People as children. Teams may have Teams (i.e., sub-teams) and People as children.
[0048] It is also possible that some of the same node types can be present in another structure type known as a “Feature Hierarchy.” In the Feature Hierarchy, imagine that the following node types are used: Group, Team, Component, and Feature Area. Note that the same node type definitions are used for Group and Team, but that Division and Department are missing because they are unimportant in the Feature Area hierarchy.
[0049] Structural constraint(s) 230 describe the permissible parent-child relationships between various node types 210 . For instance, a node of type Organization Unit might be at the root and may be parent to more Organization Units. Eventually, an Organization Unit might decompose into Components or Feature Areas, neither of which can subsequently be the parent of an Organization Unit.
[0050] A structure 130 is an actual instance of a structure that conforms to a structure type 200 . For instance, given the “Organization Breakdown” structure type, a structure based on that type in a plumbing supplies component might look something like:
Potable Water: Division - Thurman Talbott, Senior VP: Person - Installation: Group - Arden Snellbling, VP: Person - Copper Pipes: Department - Bert Nurnie, Department Head: Person - King County: Team - Seattle: Team - Anne Rice, Lead: Person - Davey Talbott: Person - Doogie Howser: Person - Eastside: Team ... - Snohomish Country: Team ... - Non-copper Pipes: Department ... -Maintenance: Group ... - Non-potable Water and Sewage Treatment: Division ...
The bold entries refer to the node type 210 of each node. The structure also conforms to the constraints as described supra for the Organizational Breakdown structure type.
[0051] FIG. 3 illustrates an exemplary classification meta model 300 in accordance with an aspect of the subject invention. The classification meta model 300 illustrates various concepts involved in a structure and the relationships between them. This model is provided for purposes of clarity and understanding and is not meant to limit the scope of the present invention in any manner. Those of skill in the art upon reading this specification will appreciate a multitude of different variations of the model, which are all considered within the scope of the subject invention. In order to make sense out of the model it is helpful to break it into two sections or components: the structure type component 200 and the structure component 130 . To facilitate description and for purposes of clarity the following sections use an abbreviated notation for describing navigation through instances of the model 300 . In particular, the convention is to use role names (e.g., the names on the lines that are preceded by “+”) and attribute names (e.g., the names of the things inside boxes) to form an expression that describes a navigation path. For example, imagine that you need to navigate from an instance of a node class to its parent node to find out what the name of its parent node's node type is. The following expression says exactly that in an efficient manner:
Node.parent.ofType.Name
This terse rendering can be interpreted as follows. First, start at some node. From that node, follow the node at the end of the association that has a +parent role, that is navigate to the node's parent. Thus, so far we have: Node.parent. Now, starting from the newly discovered parent node, navigate to its node type. This can be accomplished by following the association between node and node type. The role name to follow here is “ofType. Now we have: Node.parent.ofType. Finally, once on the parent node type instance, you have to return the name attribute. Here it is some string. Sometimes for the sake of clarity, an expression can include the name of the class to which a role points indicated in an expression. When this is done, the role can be separated from its type name with a colon, as follows:
Node.parent:Node.ofType:NodeType.Name.
Furthermore, the types of attributes can be tacked on, as here:
Node.parent:Node.ofType:NodeType.Name:String
[0052] The following section describes details of attribute, associations, and rules in which meta model classes participate. It is divided into two sections: Structure Type and Structure.
Structure Type
[0053] In the Structure type section, the kinds of hierarchies that can be formed by combining node types in various ways are defined. As previously mentioned, a structure type section or component can include three types: structure type class, node type, and structural constraint. The structure type class holds the name of the structure type and identifies whether or not it is a hierarchy. Examples of structure type class include Organizational Hierarchy, Feature Area Hierarchy, Release Hierarchy, and Work Item Status Types. The node type defines the kind of thing that will be in a structure. Examples of node types include Organization Unit, Component, Feature Area and Milestone. For each Node based on a node type, certain information can be present, such as name and description. Structural constraints describe the permissible parent-child relationships between various node types. For example, a node of type Organization Unit might be at the root and may be the parent to more Organization Units. Eventually, an Organization Unit might decompose into Components or Feature Areas, neither of which can subsequently be the parent of an Organization Unit.
[0054] Structure type class can further be defined by the following attributes and associations:
Attributes Name: String The name of the structure type. Must be unique. IsHierarchy: If true, this structure type represents a hierarchical Boolean arrangement of nodes. If false, this structure type represents a flat list. Note: The value of this attribute can actually be determined by the absence of StructuralConstraint instances (which describe permissible parent-child relationships.) However, it seemed important to explicitly distinguish between a hierarchy and a list. Associations contains: The NodeTypes defined for this structure type . . . NodeType [1 . . . *] for: Structure Each specific Structure should be defined by a [0 . . . *] Structure Type.
[0055] Node type can be further defined by the following attributes and associations:
Attributes Name: String The name of the node type should be unique. Examples: Organization Unit Component Feature Area Milestone Description: String Optional node type description. Icon: Image The default icon that appears in tree controls when a node of this type is displayed. Attributes CandidateRoot: Boolean Indicates whether nodes of the referenced type (type: NodeType) can appear as top-level nodes in the hierarchy. CandidateLeaves: Boolean Indicates whether nodes of the referenced type (type: NodeType) can appear as lowest-level nodes in the hierarchy. Associations container: Each NodeType is owned by a StructureType. StructureType [1] for: Node [0 . . . *] Each node points to its corresponding node type. mayBeParentOf: The navigation path StructuralConstraint Node Type.mayBeParentOf.CandidateChild.type: NodeType indicates that a [0 . . . *] node of the first NodeType can be the parent of a node of the second NodeType. This association is used to constrain the nodes that can appear in an actual Structure. mayBeChildOf: The navigation path StructuralConstraint NodeType.mayBeChildOf.CandidateParent.type: NodeType indicates that a [0 . . . *] node of the first NodeType can be the child of a node of the second NodeType. This association is used to constrain the nodes that can appear in an actual Structure.
[0056] Structural constraints can be further defined as follows:
Associations CandidateParent: NodeTypeUsage [1] Paired with CandidateChild, describes the potential for nodes of the NodeType's to be parents of nodes of the candidateChild's NodeType's. CandidateChild: NodeTypeUsage [1] See above.
Structure
[0057] This section describes the actual instance of nodes. The present invention governs the composition and content of these based on the definitions of related node type and structure type class. The following provides details regarding structure attributes and associations:
Attributes Name: String The name of the structure. Should be unique but may have the same name as its StructureType. Description: String A description of the structure. Appears as a tooltip. Attributes IsDistinguished: Boolean Indicates whether a tool wants to treat this structure as its Distinguished Hierarchy Associations ofType: StructureType [1] Identifies the StructureType that describes the constraints to which this Structure may belong. rootNode: Node [1 . . . *] The set of top-level nodes in this structure. Note that this hierarchy does not have a single root node. What follows is a detail specification of attributes and associations for nodes. Attributes Name: String Each node should be uniquely named among all of its siblings. Associations anchoredBy: Structure [0 . . . 1] Each top-level node is directly associated with Structure via anchoredBy. parent: Node [0 . . . 1] Identifies the parent of the node.
EXAMPLE
[0058] The following example utilizes instance diagrams to illustrate how specific instances of the classes described in the preceding sections are employed to represent a structure. To start, assume that we want two structures ( FIGS. 4-5 ) organized as follows:
1. Project Lifecycle hierarchy that is made up of a set of decomposing Life Cycle Item nodes. FIG. 4 illustrates an example of part of a Project Lifecycle hierarchy 400 . 2. A Project Model hierarchy that involves nodes of three types: (a) Organizational Unit; (b) Component; and (c) Feature Area. 3. The relationships between the nodes of various types in the Project Hierarchy follow these rules:
a. The top nodes in the hierarchy should be Organizational Units. b. Each child of an Organizational Unit can be one of the following:
i. A subordinate Organizational Unit; ii. A Component; or iii. A Feature Area.
c. Each child of a Component can be either:
i. A subordinate Component; or ii. A Feature Area.
d. Each child of a Feature Area can be either:
i. A subordinate Component; or ii. A Component.
e. In this example, none of the nodes are obliged to have children. In other words, the decomposition can stop with an Organizational Unit, a Component, or a Feature Area.
FIG. 5 illustrates an exemplary portion of the Project Model hierarchy 500 in accordance with the present example.
[0074] The present example involves two structures (i.e., Project Lifecycle and Project Model Hierarchy), each of which has a different set of allowable node types. Thus, a structure type needs to be defined for each structure to specify which kinds of nodes a customer can enter into the structure and the parent-child relationships in which such nodes can participate. Turning first to FIG. 6 a, an instance diagram 610 is depicted. For the Project Lifecycle structure, there is a single node type called LifeCycleltem. Accordingly, the instance diagram 610 shows the name and description for the single node type, here something temporal.
[0075] To define how nodes of this type can be assembled to form a hierarchy, a structure type class is required. On the eLead team, a hierarchy made up of temporal nodes is dubbed a “When” hierarchy so the structure type class can be called “When.” FIG. 6 b illustrates instances that compose the When structure type class. Although not shown in the figure, assume that the attributes CandidateRoot and CandidateLeaf are set to true. This indicates that when the user builds a structure based on the When structure type she can have a node based on LifeCycleItem at both the top and the bottom of the hierarchy. The structural constraint hanging from the node type LifeCycleItem indicates that the structural constraint can be the parent of a LifeCycleItem and that a LifeCycleItem can be the child of a LifeCycleltem. In other words, the hierarchy is a tree LifeCycleItems
[0076] Turning to FIG. 7 , an instance diagram 700 is illustrated. Instance diagram 700 depicts the specific instances that make up the Project lifecycle structure illustrated by FIG. 4 . The Project Lifecycle structure is based on the “When” structure type. FIG. 7 is fine as far as it goes, but it does not show the specific types of Structure or Node involved on which the structure and nodes in this diagram are based. That is, there is no way to tell from this instance that the node labeled “A” is a LifeCycleItem.
[0077] FIG. 8 depicts yet another instance diagram 800 in accordance with an aspect of the subject invention. In order to understand which nodes are which the instance diagram 700 ( FIG. 7 ), the Project Life cycle structure must be mapped to the instance diagram 620 ( FIG. 6 b ) that defines the When structure type class. The mapping is illustrated in instance diagram 800 . It should be appreciated that for readability, the think line represents an instance of the association Structure.ofType:StructureType and the thinner lines represent instances of the association Node.ofType:NodeType. The diagram is pretty straightforward in this very small model where there is only one node type. However, the importance of the constraints represented by the structure type model becomes clearer when the model is more complex as in the case of the Project Model Hierarchy.
[0078] The Project Model Hierarchy involves three node types: Organizational Unit, Component, and Feature Area. A structure that starts off as an organization hierarchy and morphs into feature areas and components as it is decomposed can be informally called a Who/Where structure. Thus, the structure type class on which this structure is based WhoWhere.
[0079] Turning to FIG. 9 , an instance diagram 900 is illustrated. The diagram 900 illustrates fundamental elements of the WhoWhere hierarchy, but something is missing. It is possible from the diagram to determine that Organizational Unit nodes can be at the top of the hierarchy and that Feature Areas and Components cannot be based on the value of their respective CandidateRoot properties (NodeType.CandidateRoot). However, it says nothing about whether an Organizational Unit can contain a Feature Area (which is allowed) or whether a Feature Area can contain an Organizational Unit (which is not allowed). This additional constraint is specified by introducing Structural Constraint instances that define who can be the parent of whom. This clutters the model up a bit, but is extremely flexible. Turning briefly to FIG. 10 , a structural hierarchy 1000 is illustrated. Structural hierarchy 1000 describes all the constraints on the Project Model Hierarchy previously mentioned. Furthermore, structural constraints are illustrated specifying parent and child relationships amongst type nodes.
User Interfaces and the Meta Model
[0080] There are at least two distinct kinds of users of the common structures of the present invention. The first and most common is an end user of common structures. The second is a structure administrator. This section deals with each of these types of users in turn.
[0081] Furthermore, it should be appreciated that there are a myriad of environments from which an end user and an administrator might interact with common structures. For example, a user can interact with common structures via a Web environment. Additionally or alternatively, a user can interact with common structures within other applications such as a programmatic shell environment (e.g., Microsoft's Visual Studio) or other less rich client.
[0082] Turning to FIG. 11 , an exemplary graphical user interface 1100 is illustrated in accordance with an aspect of the present invention. The interface 1100 depicts a common structure interface 1110 embedded or integrated into a defect-tracking tool. As shown, the common structure interface 1110 is a single windowpane amongst many other windowpanes in a graphical display. The name of the structure (e.g., structure.name), here Project Model Hierarchy, is provided in a title bar 1112 . Nodes associated with the particular structure can then be graphically represented and organized in a hierarchy. Furthermore, each node in the hierarchy can be displayed with an associated icon and/or node string to facilitate node identification. Additionally, nodes can be indented, as in most hierarchical representations, to indicate child association. For instance, Data Integration, Control Integration, and Administrative Services are all child nodes of Enterprise Integration Services. Thus, an end-user does not have to view the common structures as independent constructs at least because each such structure can be integrated into the overall user experience of tools that reference it.
[0083] FIG. 12 depicts another exemplary graphical user interface 1200 incorporating common structures. Here, another bug tracking system interface 1200 is illustrated. However, in this instance a user interface helper control 1210 is shown. The user interface helper control 1210 can be employed to facilitate selection of a classification node from within the bug tracking user interface. The interface helper control 1210 can include one or more of a plurality of graph components (e.g., icons, text, boxes, buttons, tabs . . . ). Here, interface helper control 1210 is shown as a drop down menu.
[0084] The graphical interface components in FIGS. 11 and 12 provide exemplary means of interaction with common structures. Such interaction can include viewing structures, adding nodes, renaming nodes and deleting nodes. In one instance, structure nodes can be explored utilizing a tree as in FIG. 11 . Furthermore, the interface components can be used to attach something to a node in a structure, for instance, by dragging and dropping either to of from a node on the tree view. For example, a requirement might be mapped to a node in a structure by dropping the requirement onto the structure. Additionally or alternatively a drop-down menu can be employed as in FIG. 12 . In such case, something can be attached to a node in a common structure by selecting from the drop-down menu. Furthermore, it should be appreciated that a role-base filter can be applied to restrict a user's view to a particular set of nodes. This is useful for scoping a user's view to a specific project or application in which he or she is interested.
[0085] Turning to FIG. 13 , a structure maintenance tool 1300 is illustrated in accordance with an aspect of the subject invention. An administrator can modify structures by adding, changing, or deleting nodes by using a structure maintenance tool 1300 . The tool 1300 can include a tree section 1310 and a properties section 1320 . As illustrated, the exemplary administrator maintenance interface tool appears similar to the end-user tree view, however it contains some subtle and some not so subtle differences that make it a powerful ally to a beleaguered administrator. In particular, all structures are shown in the structure maintained tool bar in the tree section 1310 . Furthermore, properties section 1320 provides more specific information regarding structures and nodes. Additionally, it should be appreciated that the structure maintenance tool 1300 can enable authorized users to add new structures and/or nodes.
Common Structure Representation
[0086] The structures of the present invention are common structures intended for use by a multitude of similar or varying components and subcomponents. As a result and in accordance with an aspect of the invention, the common structures can be exposed to consumers and manipulators as XML (eXensible Markup Language) documents. Furthermore, in order to make XML documents more accessible to users they can be typed. That is to say, instead of seeing XML elements with tags of the general types node, node type, and property type a consumer will see nodes that are typed according to their structure type. For example:
<ProjectModelHierarchy type=“WhoWhere”> <OrganizationalUnit NodeID=“immutable001” > <Name>Enterprise</Name> <OrganizationalUnit NodeID=“immutable002” > <Name>eLead</Name> <OrganizationalUnit NodeID=“immutable003” > <Name>IntegrationInfrastructure</Name> <Component NodeID=“immutable004” > <Name>EnterpriseIntegrationServices</Name> <FeatureArea Node ID=“immutable005”> <Name>DataIntegration</Name> </FeatureArea> <FeatureArea NodeID=“immutable006” > <Name>ControlIntegration</Name> </FeatureArea> <FeatureArea NodeID=“immutable007” > <Name>AdministrativeServices</Name> </FeatureArea> </Component> <Component NodeID=“immutable008” > <Name>BISUtilities</Name> </Component> </OrganizationalUnit> <OrganizationalUnit NodeID=“immutable009” > <Name>RequirementsManagement</Name> </OrganizationalUnit> </OrganizationalUnit> <OrganizationalUnit NodeID=“immutable010” > <Name>Quality Tools</Name> <FeatureArea NodeID=“immutable011” > <Name>TestCaseManagement</Name> </FeatureArea> <FeatureArea NodeID=“immutable012” > <Name>UnitTesting</Name> </FeatureArea> </OrganizationalUnit> </OrganizationalUnit> </ProjectModelHierarchy>
Event Monitoring and Notification
[0087] Turning to FIG. 14 , an event monitoring system 1400 is described in accordance with an aspect of the subject invention. Event monitoring system 1400 comprises event monitor component 1410 , classifiable artifacts 1420 and notification system 1430 . Once a common structure has been established it can be monitored for events such as additions, deletions, and other manipulations thereto. Classifiable artifacts 1430 are pieces of data worth keeping track of which can also be classified. Monitor component 1410 monitors classifiable artifacts for changes. Upon detection of a valid alteration, such information can be passed to notification system 1430 to notify one or more designated parties.
[0088] FIG. 15 illustrates a notification system 1500 in accordance with an aspect of the present invention. Notification system 1500 comprises event engine component 1510 , rule processor component 1520 , event store 1530 , subscription store 1540 , and client communication component 1550 . Event engine component 1510 receives information concerning a change to a structural artifact. Thereafter, event engine component 1510 can then utilize event store 1530 to classify the occurrence. Then it can match the event to the subscriptions residing in subscription store 1540 . Subscriptions can contain notification information such as whether to alert or not, who to notify (e.g., person, group, role), and preferred means of notification (e.g., email, pager, personal digital assistant . . . ). If a notification-worthy event occurs that matches a subscription, notification data can be provided to client communication component 1550 . Client communication component 1550 provides a mechanism for notifying a user of an event. For example, communication component 1550 can push the message to a user's email. Additionally or alternatively, the notification message could be pulled from a location by a user or user device.
[0089] Furthermore, the subject invention also contemplates providing notification prior to affecting a change to the classification structure. For example, a before change event can be raised to all consumers of the structure to give them and opportunity to veto the change or approve the change. Additionally or alternatively, an after change event can be raise to all consumers to enable them to reflect a change that has bee committed. For instance they can ensure that any artifact that refers to a node id is still valid.
Methodologies
[0090] In view of the exemplary system(s) described supra, a methodology that may be implemented in accordance with the present invention will be better appreciated with reference to the flow charts of FIGS. 16-17 . While for purposes of simplicity of explanation, the methodology is shown and described as a series of blocks, it is to be understood and appreciated that the present invention is not limited by the order of the blocks, as some blocks may, in accordance with the present invention, occur in different orders and/or concurrently with other blocks from what is depicted and described herein. Moreover, not all illustrated blocks may be required to implement the methodology in accordance with the present invention.
[0091] Additionally, it should be further appreciated that the methodologies disclosed hereinafter and throughout this specification are capable of being stored on an article of manufacture to facilitate transporting and transferring such methodologies to computers. The term article of manufacture, as used, is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. By way of illustration and not limitation, the article of manufacture can embody computer readable instructions, data structures, schemas, program modules, and the like.
[0092] FIG. 16 illustrates a common classification methodology 1600 in accordance with an aspect of the present invention. At 1610 one or more taxonomies or structures are generated. These structures can include a myriad of globally unique and immutable nodes. The actual process of generating a taxonomy can comprise defining node types and structure type classes. A node type can specify the kind of thing included in a structure. For example, as structure might include Divisions, Groups, Teams, and People. A structure type class describes how a set of nodes of various node types can be assembled into a list or hierarchy. For example, the top nodes in the structure must be Divisions. Furthermore, generating a taxonomy can comprise defining structural constraints defining parent child relationships and more specifically who can be the parent of whom. The actual generation of the taxonomy can be achieved in several ways. First, a user or administrator can define the taxonomy utilizing a graphical interface. For instance, a user can drag and drop software artifacts on to classification nodes. Additionally, it should be appreciated that a user can import a taxonomy from a source. Still further yet, it should be noted and appreciated that heuristics and statistical analysis, such as those involved in artificial intelligence, can be utilized alone or in conjunction with other methods to generate a common classification taxonomy. At 1620 , the classification is maintained to facilitate interaction with taxonomy artifacts by a plurality of unrelated tools. One manner of maintaining the taxonomy includes providing consumers of the taxonomy notification of a proposed change thereto so as to provide the consumer an opportunity to object. Furthermore, notification can be provided to consumers when changes are actually made or are about to be made so that they can compensate for the change to ensure reliable operation. For example, a classification consumer can ensure that any artifact that refers to a node id is still valid. Because node id is immutable according to an aspect of the invention, in most cases an artifact provider will not be affected unless a node is deleted. Hence, the methodology 1600 provides a way for unrelated tools to categorize elements they control according to a common centrally managed classification taxonomy. To that end, it should be appreciated that the taxonomy can be specified in XML (eXtensible Markup Langauge) to facilitate use and interpretation by differing and unrelated tools.
[0093] FIG. 17 is a flow chart diagram illustrating an enterprise classification scheme methodology 1700 in accordance with an aspect of the present invention. At 1710 a common structure is instantiated base on a structure type. A structure is an actual instance of a structure that conforms to a structure type. The structure type can be defined by node type, structure type class, and structural constraints. As mentioned supra, a node type defines the kind of thing you can include in a structure. A Structure type class defines how a group or set of nodes can be combined in a hierarchy, for example, while the structural constraints define which nodes can be the parent of which nodes. At 1720 , the common structures can be exposes amongst a plurality of unrelated tools. Furthermore, the common structures can be exposed to users via a graphical user interface and associated API (Application Programming Interface). Finally, at 1730 , consent can be requested of structure consumers to proposed changes in the structure. This gives consumers time to review the proposed change before it is committed and possibly object.
Sample Operating Environments
[0094] In order to provide a context for the various aspects of the invention, FIGS. 18 and 19 as well as the following discussion are intended to provide a brief, general description of a suitable computing environment in which the various aspects of the present invention may be implemented. While the invention has been described above in the general context of computer-executable instructions of a computer program that runs on a computer and/or computers, those skilled in the art will recognize that the invention also may be implemented in combination with other program modules. Generally, program modules include routines, programs, components, data structures, etc. that perform particular tasks and/or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the inventive methods may be practiced with other computer system configurations, including single-processor or multiprocessor computer systems, mini-computing devices, mainframe computers, as well as personal computers, hand-held computing devices, microprocessor-based or programmable consumer electronics, and the like. The illustrated aspects of the invention may also be practiced in distributed computing environments where task are performed by remote processing devices that are linked through a communications network. However, some, if not all aspects of the invention can be practiced on stand-alone computers. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.
[0095] With reference to FIG. 18 , an exemplary environment 1810 for implementing various aspects of the invention includes a computer 1812 . The computer 1812 includes a processing unit 1814 , a system memory 1816 , and a system bus 1818 . The system bus 1818 couples system components including, but not limited to, the system memory 1816 to the processing unit 1814 . The processing unit 1814 can be any of various available processors. Dual microprocessors and other multiprocessor architectures also can be employed as the processing unit 1814 .
[0096] The system bus 1818 can be any of several types of bus structure(s) including the memory bus or memory controller, a peripheral bus or external bus, and/or a local bus using any variety of available bus architectures including, but not limited to, 11-bit bus, Industrial Standard Architecture (ISA), Micro-Channel Architecture (MSA), Extended ISA (EISA), Intelligent Drive Electronics (IDE), VESA Local Bus (VLB), Peripheral Component Interconnect (PCI), Universal Serial Bus (USB), Advanced Graphics Port (AGP), Personal Computer Memory Card International Association bus (PCMCIA), and Small Computer Systems Interface (SCSI).
[0097] The system memory 1816 includes volatile memory 1820 and nonvolatile memory 1822 . The basic input/output system (BIOS), containing the basic routines to transfer information between elements within the computer 1812 , such as during start-up, is stored in nonvolatile memory 1822 . By way of illustration, and not limitation, nonvolatile memory 1822 can include read only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable ROM (EEPROM), or flash memory. Volatile memory 1820 includes random access memory (RAM), which acts as external cache memory. By way of illustration and not limitation, RAM is available in many forms such as synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM).
[0098] Computer 1812 also includes removable/non-removable, volatile/non-volatile computer storage media. FIG. 18 illustrates, for example disk storage 1824 . Disk storage 4124 includes, but is not limited to, devices like a magnetic disk drive, floppy disk drive, tape drive, Jaz drive, Zip drive, LS- 100 drive, flash memory card, or memory stick. In addition, disk storage 1824 can include storage media separately or in combination with other storage media including, but not limited to, an optical disk drive such as a compact disk ROM device (CD-ROM), CD recordable drive (CD-R Drive), CD rewritable drive (CD-RW Drive) or a digital versatile disk ROM drive (DVD-ROM). To facilitate connection of the disk storage devices 1824 to the system bus 1818 , a removable or non-removable interface is typically used such as interface 1826 .
[0099] It is to be appreciated that FIG. 18 describes software that acts as an intermediary between users and the basic computer resources described in suitable operating environment 1810 . Such software includes an operating system 1828 . Operating system 1828 , which can be stored on disk storage 1824 , acts to control and allocate resources of the computer system 1812 . System applications 1830 take advantage of the management of resources by operating system 1828 through program modules 1832 and program data 1834 stored either in system memory 1816 or on disk storage 1824 . Furthermore, it is to be appreciated that the present invention can be implemented with various operating systems or combinations of operating systems.
[0100] A user enters commands or information into the computer 1812 through input device(s) 1836 . Input devices 1836 include, but are not limited to, a pointing device such as a mouse, trackball, stylus, touch pad, touch screen, keyboard, microphone, joystick, game pad, satellite dish, scanner, TV tuner card, digital camera, digital video camera, web camera, and the like. These and other input devices connect to the processing unit 1814 through the system bus 1818 via interface port(s) 1838 . Interface port(s) 1838 include, for example, a serial port, a parallel port, a game port, and a universal serial bus (USB). Output device(s) 1840 use some of the same type of ports as input device(s) 1836 . Thus, for example, a USB port may be used to provide input to computer 1812 and to output information from computer 1812 to an output device 1840 . Output adapter 1842 is provided to illustrate that there are some output devices 1840 like monitors, speakers, and printers, among other output devices 1840 that require special adapters. The output adapters 1842 include, by way of illustration and not limitation, video and sound cards that provide a means of connection between the output device 1840 and the system bus 1818 . It should be noted that other devices and/or systems of devices provide both input and output capabilities such as remote computer(s) 1844 .
[0101] Computer 1812 can operate in a networked environment using logical connections to one or more remote computers, such as remote computer(s) 1844 . The remote computer(s) 1844 can be a personal computer, a server, a router, a network PC, a workstation, a microprocessor based appliance, a peer device or other common network node and the like, and typically includes many or all of the elements described relative to computer 1812 . For purposes of brevity, only a memory storage device 1846 is illustrated with remote computer(s) 1844 . Remote computer(s) 1844 is logically connected to computer 1812 through a network interface 1848 and then physically connected via communication connection 1850 . Network interface 1848 encompasses communication networks such as local-area networks (LAN) and wide-area networks (WAN). LAN technologies include Fiber Distributed Data Interface (FDDI), Copper Distributed Data Interface (CDDI), Ethernet/IEEE 802.3, Token Ring/IEEE 802.5 and the like. WAN technologies include, but are not limited to, point-to-point links, circuit switching networks like Integrated Services Digital Networks (ISDN) and variations thereon, packet switching networks, and Digital Subscriber Lines (DSL).
[0102] Communication connection(s) 1850 refers to the hardware/software employed to connect the network interface 1848 to the bus 1818 . While communication connection 1850 is shown for illustrative clarity inside computer 1812 , it can also be external to computer 1812 . The hardware/software necessary for connection to the network interface 1848 includes, for exemplary purposes only, internal and external technologies such as, modems including regular telephone grade modems, cable modems, DSL modems, power modems, ISDN adapters, and Ethernet cards.
[0103] FIG. 19 is a schematic block diagram of a sample-computing environment 1900 with which the present invention can interact. The system 1900 includes one or more client(s) 1910 . The client(s) 1910 can be hardware and/or software (e.g., threads, processes, computing devices). The system 1900 also includes one or more server(s) 1930 . The server(s) 1930 can also be hardware and/or software (e.g., threads, processes, computing devices). The servers 1930 can house threads to perform transformations by employing the present invention, for example. One possible communication between a client 1910 and a server 1930 may be in the form of a data packet adapted to be transmitted between two or more computer processes. The system 1900 includes a communication framework 1950 that can be employed to facilitate communications between the client(s) 1910 and the server(s) 1930 . The client(s) 1910 are operably connected to one or more client data store(s) 1960 that can be employed to store information local to the client(s) 1910 . Similarly, the server(s) 1930 are operably connected to one or more server data store(s) 1940 that can be employed to store information local to the servers 1930 .
[0104] What has been described above includes examples of the present invention. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the present invention, but one of ordinary skill in the art may recognize that many further combinations and permutations of the present invention are possible. Accordingly, the present invention is intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, to the extent that the term “includes or having” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim. | The present invention provides a system and method for unrelated tools to categorized elements they control according to a common centrally managed classification scheme. The invention also provides a mechanism for storing, retrieving, and modifying classifying information. Users of unrelated tools that employ the subject invention see a single and consisted user interface. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to diagnostic x-ray systems which produce a diagnostic x-ray image, and is specifically directed to systems of this type having an adjustable primary radiation diaphragm.
2. Description of the Prior Art
Radiation systems, for example computer tomography systems, are known in the art wherein an x-ray fan beam is generated for diagnostic purposes, the fan beam being formed (gated) by an adjustable primary radiation diaphragm. In known computer tomography systems of this type the primary radiation diaphragm is fashioned as a slit diaphragm, which defines the shape of the x-ray fan beam. The fan beam, in turn, defines the dose profile in the patient, and thus the thickness of the slice in an exposure. The fan beam thus also influences the dose load on the patient and the intensity of the detector signal from which the image data are acquired. For setting various slice thicknesses, it is necessary to set various apertures of the primary radiation diaphragm. In order to achieve an optimally high quantum yield at the radiation detector, it is necessary to insure that the center of area of the radiation fan beam be centrally incident on the detector. This means that the focus of the x-ray radiator, the center line of the primary radiation diaphragm, and the center line of the radiation detector should coincide for an optimum irradiation of the detector. Moreover, in order to insure a low dose load on the patient, it is necessary to minimize the number of required exposures. It is helpful for this purpose if the quality of each individual exposure, and thus its diagnostic content, is optimally high.
In general, the beam geometry is modified by the dynamic influences caused by rotation of the rotating part of the computer tomography apparatus and/or by thermal influences, particularly in the x-ray radiator. Such modification of the beam geometry, if not corrected, can result in a degradation of the image.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an x-ray apparatus which produces a diagnostic image, and which has an adjustable radiation diaphragm which permits precise deviations of the beam geometry from a desired beam geometry, so that deviations can be corrected when necessary.
The above object is achieved in accordance with the principles of the present invention in an x-ray apparatus having a radiation-electrical transducer on which an image of the primary radiation diaphragm aperture is produced, from which the aperture shape and position can be identified. The radiation-electrical transducer on which the image of the primary radiation diaphragm is produced is a separate element from the radiation detector on which the overall diagnostic image is produced. Output signals from the radiation-electrical transducer are supplied to evaluation electronics, so that the size and position of the primary radiation diaphragm aperture can be identified, and corrective measures can then be undertaken, if either quantity deviates from a desired value.
In the x-ray apparatus disclosed herein, the aperture size and position of the primary radiation diaphragm are identified, preferably relative to the rotating reference plane in the case of computer tomography apparatus. The x-ray apparatus disclosed herein is particularly suited for use with a motor-adjustable primary radiation diaphragm.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of the basic components of a computer tomography apparatus, for use in explaining the inventive concept.
FIG. 2 shows a first optical system for acquiring the size and position of the aperture of the primary radiation diaphragm in the computer tomography apparatus of FIG. 1, in accordance with the principles of the present invention.
FIG. 3 shows a second optical system for acquiring the size and position of the primary radiation diaphragm aperture in the computer tomography apparatus of FIG. 1, in accordance with the principles of the present invention.
FIG. 4 is a block diagram of evaluation electronics for evaluating the signals obtained from either of the optical systems shown in FIGS. 2 and 3, in accordance with the principles of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The rotating part of a computer tomography apparatus is shown in FIG. 1. The apparatus includes an x-ray radiator 1 having a focus 2, and a radiation detector 3. The x-ray radiator 1 and the radiation detector 3 rotate around an axis 4 in a known manner. A primary radiation 5, having an adjustable aperture, generates a fan-shaped x-ray beam 6 which transirradiates a patient (not shown) through which the axis 4 proceeds. The patient is transirradiated from various directions given rotation of the radiation detector 1 and the radiation detector 3, and a computer calculates an image of the transirradiated portion of the patient from the output signals of the radiation detector 3. The fan plane proceeds perpendicularly relative to the plane of the drawing, and the detector 3 is composed of a number of discreet radiation detectors which also extend perpendicularly relative to the plane of the drawing, and are curved around the focus 2. Only those components of the primary radiation diaphragm 5 are shown which define the thickness of the fan-shaped x-ray beam 6. The aperture angle is defined by other parts which are not shown in FIG. 1, and which do not form a part of the invention disclosed herein.
An optical system is shown in FIG. 2 for acquiring the diaphragm aperture size and position in the tomography apparatus shown in FIG. 1. The system of FIG. 2 includes a light-emitting diode 7 which emits light through the primary radiation diaphragm 5 via an optical diaphragm 8 and a lens 9. The part of the light which passes through the primary radiation diaphragm 5 is incident on a CCD line sensor 10. The irradiated part of the line sensor 10 thus corresponds to the particular aperture size and position of the primary radiation diaphragm 5. Electrical signals corresponding to the diaphragm aperture size and position are formed from the output signals of the line sensor 10 by suitable evaluation electronics, as described below in combination with FIG. 4. The CCD line sensor 10 is a separate element from the radiation detector 3.
The imaging ensues according to FIG. 2 with a 1:1 imaging scale on the basis of shadow-casting.
It is also possible to employ a more complicated optical system in order to be able to achieve other imaging scales or other functions such as, for example, non-linear imaging, minimization of refraction effects, or minimization of mechanical tolerances.
FIG. 3 shows such an optical system wherein two light-emitting diodes 11 shine onto the underside (i.e., the side facing away from the x-ray radiator 1) of the diaphragm plates of the primary radiation diaphragm 5. The plates reflect the light from the light-emitting diodes 11, and the reflected light is directed onto the sensor 10 via a lens 12, and is registered by the sensor 10. Again, the sensor 10 is a separate element from the radiation detector 3.
Instead of a separate light source for illuminating the sensor 10, it is also possible to exploit the x-ray radiation which is already being generated. A regulation of the illumination level is useful in order to compensate for aging effects and contamination effects and in order to optimally modulate the sensor 10, as well as to be able to recognize outage of the illumination unit, if it occurs. To this end, the intensity of the light-emitting diodes 7 and 11 can be made variable in the embodiments shown in FIGS. 2 and 3. Moreover, other sensors, for example a photodiode array, may be employed as the sensor 10 instead of a CCD line sensor. Given the illustrated CCD line sensor 10, a locational identification of the edges of the primary radiation diaphragm 5 can be made simply by counting the illuminated pixels, given a predetermined pixel spacing.
Other sensors such as, for example, PSD (position sensitive device) sensors can be employed, wherein measurement of the diaphragm position ensues indirectly via an intensity measurement on the basis of the center of gravity formation, in a manner which is known in the art, and by measuring the size of the aperture image thereon.
As shown in FIG. 4, the sensor 10 is connected to an input amplifier 13 of evaluation electronics. The amplifier 10 is for offset and level matching of the CCD output signal, plus filtering as needed, for conditioning the signal which is supplied to the remainder of the evaluation electronics. The output signal from the input amplifier 13 is supplied to a Min/Max. detector 14 which identifies the minimum and maximum brightness for the determination of a comparison threshold. The output of the min/max detector 14 is supplied to one input of a comparator 15, to which the output from the input amplifier 13 is also supplied. The comparator 15 identifies the bright and dark pixels of the sensor 10. The output of the comparator 15 is supplied to two counters 16a and 16b for determining the chronological references, and thus the spatial reference of the bright/dark transitions. One counter counts the time (i.e., the number of pixels) until the first dark/bright transition is reached, and the other counter counts the time (i.e., the number of pixels) until the first bright/dark transition is reached.
Control electronics 17 generate the various signals necessary for sequencing the evaluation procedure. The control electronics 17 generates, for example, the start signal for starting the read-out of a new line of the sensor 10, signals for resetting the counters 16a and 16b, and a clock signal for controlling read-out of a line of the sensor 10 and for incrementing the counters 16a and 16b.
The outputs of the counters 16a and 16b are supplied to an interface 18 to a higher-ranking system, for example a computer or a display unit (not shown).
Optionally, an analog-to-digital converter 19 can be provided for acquiring each pixel individually in combination with a computer 20.
The evaluation is based on the fact that, by the operation of the sensor 10, there is a strict relationship between the time axis of the output signal and the position axis of the sensor 10, so that conclusions regarding the location of the aperture imaged thereon can be made by making a time identification. Since the imaging of the edges of the aperture usually does not ensue sharply enough so that a bright-dark transition will occur precisely between one pixel and its neighboring pixels (the transition usually being distributed over a number of pixels), a decision or a comparison threshold is undertaken which defines the location (time) at which a transition from bright to dark or from dark to light is made. For example, the threshold can be identified as an average value of the bright and dark pixels, and may also serve the purpose of brightness control of the illumination unit.
The simultaneous measurement of the diaphragm aperture size and position has the following consequences:
The demands made on the stability of the focus location of the x-ray radiator 1 (thermal focus motion and position of the installation location) can be reduced, because the primary radiation diaphragm 5 can be re-adjusted given a movement of the focus location. Moreover, dynamic influences (for example, gravitation and centrifugal force) can be corrected by re-adjusting the primary radiation diaphragm 5 during the image pickup. The effective aperture of the primary radiation diaphragm 5 (and thus, the slice thickness) can easily be identified. The adjustment can be simplified because manual mechanical adjustment in conjunction with the motor-adjustment of the primary radiation diaphragm 5 is not necessary, and an absolute scale for the diaphragm motion is established by the position of the sensor 10. Moreover, if separate sensors are disposed to the left and right of the primary radiation diaphragm 5, tilting of the primary radiation diaphragm 5 can be recognized and can be reported at the same time as the aperture size and position are being reported and, depending on the details of the diaphragm adjustment mechanism, such tilting may be simultaneously compensated.
Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventor to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of his contribution to the art. | An x-ray apparatus is provided which allows the diaphragm aperture and the diaphragm position to be precisely identified in a simple manner. For this purpose, a radiation imaging system is provided which produces an image of the aperture of the primary diaphragm on a radiation-electrical transducer, the radiation-electrical transducer on which the aperture is imaged being separate from the radiation detector on which the complete diagnostics image is produced. The radiation-electrical transducer is followed by evaluation electronics for forming electrical signals corresponding to the diaphragm aperture size and position. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Preliminary Patent Application Article No. 60/459,721, filed 2003 Apr. 03 .
FEDERALLY SPONSORED RESEARCH
[0002] Not Applicable
SEQUENCE LISTING OR PROGRAM
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] Applied robotics walking chickens, more generally stimulating poultry to move.
[0006] 2. Background of the Invention
[0007] Our invention applies robotics to the problem of agitating poultry for the purpose of increasing growth-to-feed-consumed ratios.
[0008] A major aspect of increasing a poultry farmer's profits is the maximization of the birds' growth compared to the feed consumed by the birds. Further, it is well known within the poultry industry that if a poultry farmer can get his birds to eat and drink at industry-recommended time intervals this growth-to-feed-consumed ratio can be significantly increased, thereby increasing profit. The difficulty in maximizing the growth-to-feed-consumed ratio by controlling the feeding interval has two main factors.
[0009] The first factor is that the recommended interval between feeding periods is short. For example, an often recommended time interval between feeding for broilers (chickens) is every two hours. Thus the poultry are to be induced to eat every two hours for the length of the “grow-out” period (the length of time between delivery of the hatchlings to the poultry house and harvest). This grow-out period is typically six or nine weeks in length for chicken broilers, the exact period depending on the harvest size desired.
[0010] The second factor is that poultry with in a poultry house tend to eat and drink and then rest. The birds will eventually get up to eat and drink. The elapsed rest time period is significantly longer than the industry recommended feeding interval.
[0011] In order to encourage the typically 25,000+ birds within a poultry house to get up and feed at the recommended interval, poultry farmers must “walk” the birds. In order to “walk” the birds the farmer generally walks the perimeter of each poultry house along the inner side of the exterior wall. As the farmer walks through the poultry house the birds in the farmer's immediate area will get up to get of the way. Once up, they will tend to eat and drink before settling down again. This agitation results in bird feedings at the industry-recommended interval and maximization of bird growth.
[0012] The inner perimeter of a modern poultry house is typically on the order of 1100 feet. Obviously, performing this task every two hours for a minimum of six weeks per grow-out cycle is very time intensive and taxing on the poultry farmer, especially those with multiple poultry houses. Most poultry farmers simply do not, or can not, perform this task as recommended.
[0013] The prior art employs several methods of agitating or walking the birds. The first requires that the farmer manually walk the birds by typically walking the inner perimeter of the poultry house exterior walls. This is very time consuming. Further, poultry houses are hot, humid, dusty, and have poor air quality due to such factors as higher than normal levels of carbon dioxide and the presence of ammonia vapor. Clearly, this constitutes an unpleasant and potentially unhealthy environment for the person walking the chickens. Additionally, this method requires entry into the poultry house very two hours, which in each case opens the opportunity for the unintended introduction of biological or chemical contaminants, e.g. viruses, into the poultry house.
[0014] A second prior art method requires the installation a long continuous cable, typically longer than 100 feet. In addition, a drive wheel mechanism and spaced hangers must be installed to feed the cable back and forth along the side walls and near the floor of the poultry house. The cable pulls an attached “agitator member” along the route of the cable encouraging the birds to move about.
[0015] A third prior art method of walking the birds requires an expensive and difficult to install fixed frame on the poultry house ceiling. Tracks are then suspended from the frame. These tracks control the position of a tethered object, such as a curtain, by dragging the object along beneath the track via the use of motorized trolleys. The movement of the curtain agitates the birds encouraging the birds to move about.
[0016] In both the second and third prior art examples the systems require fixed installation of considerable hardware in the form of tracks, hangers, heavy motors, and/or cable within the poultry house. The installation of such equipment represents a significant investment by the poultry farmer. Further, this is an expense and effort that must be repeated for each of the grower's poultry houses. Also, the internal configuration of poultry houses may change over the course of the grow-out period (initial subdivision of the space when the poultry chicks are small, thereby confining them to a smaller area). Accommodation of such subdivisions would require changes to the routing of fixed track or hanger configurations.
BRIEF SUMMARY OF THE INVENTION
[0017] Our invention uses an autonomously operating robot to accomplish the task of agitating the chickens. Once placed in the poultry house and activated, a robot autonomously moves through the poultry, stimulating them to move according to a programmable schedule that reflects the recommended agitation interval.
[0018] Our automated poultry walking robotic system consists of one or more robot's which periodically travel through the poultry house at user-definable time intervals consistent with industry recommendations. The robot's motion through the poultry house causes the birds to, just as in the instance of manually walking the birds, get up to eat and drink before once again resting.
[0019] Contrasting to the significant installation requirements of the prior mechanized art, the preferred embodiment of our system includes one or more robots operating in a completely self-contained manner, obviating the need for any modification to the poultry house.
[0020] The necessary robot guidance control is calculated by the robot's processor in response to position signals from on-board sensors in the form of relative distance measurements to fixed objects in the poultry house, e.g., the distance from the robot's sensors to the poultry house wall. The robot responds to the positioning signal with steering and motor speed adjustments.
[0021] The self propelled robot will move through the poultry house by navigating along the inside the perimeter of the poultry house walls. The robot accomplishes this by collecting and processing positional data received in the form of radio frequency signal strength where the signal strength is processed as distance.
[0022] The primary assembly comprising our poultry walking system is a self-propelled robot having:
An on-board power source; A sensor subsystem capable of providing signals corresponding to the range to objects in their field of view; A locomotion subsystem; An on-board computational subsystem capable of accepting input signals from the sensors, interpreting those signals as distance, and providing speed and steering commands to the locomotion subsystem based on the signal values received; A timer; and A casing and general construction tolerant of the chemically reactive poultry house environment.
[0029] The inventors recognize that different types of sensor subsystems can be employed. These include active sensors (e.g., SONAR and RADAR) and passive sensors that measure some external signal (e.g., from a radio frequency source). In the passive case, the external signal strength is used to infer distance. In this embodiment, the robot can be outfitted with one or more radio frequency (RF) receiver sensors. The robot sensor(s) receives signals from the system's radio frequency (RF) transmitter and wire loop antenna mounted in the poultry house.
[0030] Another key attribute of our invention is that the system's components are protected from the chemically reactive environment of the poultry house through the use of suitable plastics, metals, and treatments, as necessary, to protect the machine and it's electronics from degradation. Further, these same attributes that protect the components also allow the robot to be easily cleaned, e.g., with a hose.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0031] We have included the following drawings showing a system embodying the above concepts for use within a typical commercial poultry house.
[0032] FIG. 1 is a perspective front left side view of the self-propelled robot with the protective case closed.
[0033] FIG. 2 is a perspective front left side view of the machine self-propelled robot with the protective case opened showing how internal components are protected by the casing and how internal components may be accessed.
[0034] FIG. 3 is a top view of the robot with the casing top removed and internal components identified.
[0035] FIG. 4 is an external diagram of two typical poultry houses.
[0036] FIG. 5 is an interior view of the inner side of the exterior wall showing an installation of a radio frequency (RF) transmitter wire.
[0037] FIG. 6 is a diagram of an (RF) transmitter and the wire loop (RF) antenna used for positioning in a radio frequency version of the robot.
[0038] FIG. 7 is a diagram showing the installation of the RF sensors mounted to the top of the robot casing vs. internal mounting. The robot is tracking the wire as it approaches a poultry house corner.
[0039] FIG. 8 is a diagram representing a typical robot path through a poultry house.
[0040] FIG. 9 is a diagram showing the installation of SONAR sensors mounted to the top of the robot casing. The robot is tracking the wall as it approaches a poultry house corner. The processor is controlling the distance from the wall by keeping the two sensors the same distance from the wall. The forward facing sensor is ready to detect proximity to the perpendicular walls at the corners.
[0041] Although part of our system, component details that are not significant actors in the invention, such as, component mounting hardware, battery charger, wiring, and RF shielding are intentionally not shown in the drawings. Their arrangement for component connection and mounting should be well known by those of ordinary skill in the electronic and mechanical arts.
DETAILED DESCRIPTION OF THE INVENTION
[0042] In the preferred (and most simple) embodiment, the system is installed and operated as follows:
[0043] The trackless and self-propelled robot 65 is carried into a poultry 60 through a poultry house door 62 or 64 and placed within a specified distance from, and oriented parallel to, the interior side of any exterior wall 66 . Once the robot is in place power is applied and its processor 26 takes control of the robot. The robot's processor sends “commands” to the motor controller 28 to begin movement and begins to monitor its onboard sonar sensors. The robot may then be considered “installed”. Note that, in contrast to the prior art, the robot requires no installation of expensive rails, tracks, carriages, or cables within the poultry house.
[0044] The robot is autonomous in its operation. The processor begins receiving the signals from the sonar sensor(s) 94 , 95 , and 96 . Software within the processor uses the signal values to determine the robot's distance and orientation to the wall(s) 66 . The robots processor will continue to send control commands in the form of steering and motor speed commands to the motor controllers to keep the robot on a path 68 at the proper distance from, and parallel to, the wall by attempting to keep sensors 94 and 95 an equal distance from the wall until the robot reaches the stopping point or time upon which it stops its movement and enters an inactive mode. After a time equal to the recommended feeding interval the processor will begin the process again. In this way the robot can automatically agitate the poultry within a poultry house while staying clear of the feeding equipment 61 and 63 and exterior walls 66 .
[0045] As the robot travels through the poultry house the distance from the walls is maintained within a programmable minimum-maximum distance. For example, the robot can be programmed within a tolerance to maintain a distance of two to three feet from the wall. The distance from the wall as well as the robot's direction of travel relative to the wall is determined by the distance signals received from the right-front sonar sensor 94 and the right-rear sonar sensor 95 . If this distance is within the desired tolerance the robot's processor would determine that the robot can maintain its course straight ahead. If the robot is determined to be at a distance outside its tolerance and the distance is less than the minimum desired distance the processor commands the robot to turn away from the wall. If it is determined to be at a distance greater than the maximum desired distance the processor commands the robot to turn toward the wall. In either case the steering commands are proportional to the distance sensed with sharper turn commands when further out of the tolerance and lesser turn commands when less out of tolerance. For example, if the distance is two inches closer to the wall than desired the commanded turn radius away from the wall is less sharp than if the sensed distance is nine inches closer than desired. If the distance is two inches further from the wall than desired the commanded turn radius toward the wall is less than if the sensed distance is nine inches further from the wall than desired. As the robot travels strives to maintain its overall direction of travel in an orientation generally parallel to the inner side of the poultry house wall. The robot's direction of travel relative to the wall is determined by the distance signals received from the right-front sonar sensor 94 and the right-rear sonar sensor 95 . This is also achieved through processor commanded steering based on distance signals. As an example, consider one of our poultry house robots traveling counter clock wise through a poultry house. If the right-front sonar sensor 94 signal strength is not within a specified percentage of the of the distance signal strength of the right-rear sonar sensor 95 the processor can send steering commands to attempt to equalize the two distances sensed by the right front and rear sonars. For example, if the right-front sonar distance signal is significantly smaller than the right-rear sonar distance signal the robot's front is closer to the wall than the robot's rear and vice-versa.
[0046] Upon reaching the 90 degree angle of a poultry house corner the robot would be facing a wall approximately perpendicular to the robot's direction of travel. Once the forward sonar sensor 96 distance signal becomes less than or equal to a programmable distance the robot's processor will determine that the robot has reached the corner and command the robot to initiate a 90 degree turn to the left.
[0047] In an alternative embodiment a passive sensing system is used based on a radio frequency (RF) transmitting capability. The transmitter 80 is mounted within the poultry house 60 and the power cord 82 is connected to a 120V AC power source. The transmitter's wire loop antenna 72 is routed along the desired path, for example, flush with the inner side of the exterior walls near the floor. For example, see FIG. 5 where the wire antenna is attached flush to the structural posts 76 and the wooden planks 74 using staples 70 . The robot is placed in the poultry house within the specified distance from, and oriented parallel to, the wire loop antenna.
[0048] Once the transmitter, wire, and robot are in place power is applied to the transmitter and the transmitter begins emitting a low power radio frequency signal over the wire loop antenna. The robot power is applied and its processor 26 takes control of the robot. The processor sends “commands” to the motor controller 28 to begin movement. The processor begins receiving the signals from the RF sensor(s) 84 , 85 , 86 , 87 . Software within the processor determines the robot's distance and orientation to the wire loop based on differences in signal strength between RF sensors. The processor will continue to send control commands in the form of steering and motor-speed commands to the motor controller to keep the robot on a path 68 at the proper distance from, and parallel to, the wire loop until the timer reaches the stopping point. After a time equal to the recommended feeding interval the process will begin the process again. In this way the robot can automatically “walk” the poultry within a poultry house while staying clear of the feeding equipment 61 , 63 and exterior walls 66 .
[0049] As the robot travels through the poultry house the distance from the walls is maintained within a programmable minimum-maximum distance. For example, the robot can be programmed within a tolerance to maintain a distance of two to three feet from the wall. The distance is determined by the signal strength received by the RF sensors. If this distance is within this 2-3 foot tolerance the robot's processor would determine that the robot is within its “deadband” and would maintain its course straight ahead. If the robot is determined to be at a distance outside its tolerance and the distance is less than the minimum desired distance the processor commands the robot to turn away. If it is determined to be at a distance greater than the maximum desired distance the processor commands the robot to turn toward the wall. In either case the steering commands are proportional to the distance sensed with sharper turn commands as distances farther out of the tolerance increase. For example, if the distance is two inches closer to the wall than desired the commanded turn is less sharp than if the sensed distance is nine inches closer than desired. If the distance is two inches further from the wall than desired the commanded turn radius is less than if the sensed distance is nine inches further for the wall than desired.
[0050] In a radio frequency embodiment the robot also strives to maintain its orientation parallel to a wire loop 72 which has been affixed the inner side of the exterior wall around the entire perimeter of the poultry house. This is also achieved through processor commanded steering based on signal strength. As an example, consider one of our poultry house robots traveling counter clock wise through a poultry house. This robot is tracking the transmitter signal from the wire loop antenna mounted nine inches from the floor along the inner side of the exterior wall. See FIG. 5 . If the right-front RF sensor 84 signal strength is not within a specified percentage of the of the signal strength of the right-rear RF sensor 85 the processor can send steering commands to attempt to bring the two RF sensors within the same signal strength range. For example, if the right-front RF sensor signal is greater than the right-rear RF signal strength the robot front is closer to the wall (wire) than the robot's rear and vice-versa.
[0051] Similarly, upon reaching a 90 degree angle of antenna wire at a poultry house corner the left-front RF sensor 86 signal strength would rise to a level equal to the right-front RF sensor signal strength. At that point the robot's processor will command the robot to turn left. See FIG. 7 .
[0052] Note: For a given robot the on-board RF sensors are “tuned” as a matching set. This means that, if all of the RF sensors were placed at the same distance from an RF signal source, they would all provide, within a programmed tolerance, the same signal strength reading value to the processor.
[0053] The system robot 65 shown in the embodiment in the figures has steering controlled by two motors 24 . The right motor 24 drives both of the right wheels via a motor pulley 22 , axle pulley 18 , and connected by drive belts 20 . The left motor 24 drives both of the left wheels via the same arrangement. By driving the wheels on different sides at different speeds the robot can be steered. This method of steering allows for zero radius turn and also results in a simple form of four-wheel drive.
[0054] To maintain adequate robot power the farmer replenishes the battery 30 power in the robot at a duration based upon the power capabilities of battery or batteries selected. Alternatively, depending on the sensitivity of the on-board position sensors selected, the robot can also automatically recharge its batteries at a docking station. Also, a “bump” sensor can be used to, among other things, shutdown the robot if it comes up against an object in its path. The robot would then wait for the farmer to remove the obstacle and cycle the robot's power. At that point the robot would reset and begin the process again.
[0055] Our invention achieves its poultry “walking” goal by guiding the robot through the poultry house so that the poultry are stirred from their resting positions at predetermined intervals and get up to feed, drink, and to some degree exercise. This contributes greatly to the grower's ability to produce poultry that meets a desirable growth-to-feed-ratio.
[0056] Our invention achieves its ability to withstand the chemically reactive poultry house environment through the selection of materials used in construction of the robot, and supporting equipment, if any. Examples of materials and treatments which can be utilized include:
Plastics; Non-ferrous metals; Rubber or rubber-like materials; and Other material treatments which provide solutions for use in the poultry house environment. (Examples: spraying, painting, coating, plating, anodizing, etc.)
[0061] Additionally, the entirety of the robot's computational and drive components, other than the wheels and axles, are enclosed within a casing tolerant to the chemically reactive poultry house environment. However, some sensors, such as sonar sensors, may be mounted externally. Internal components may be accessed by opening the casing top 10 . FIG. 2 shows an example where the robot's electronic components may be mounted within a bottom casing 12 with a hinged 32 top casing 10 . Axle seals 34 are also used where the axles penetrate the casing.
[0062] The inventors of the automated system for walking poultry have alternative and supplemental methods of embodying our invention as described below:
Other materials, sizes, fasteners, and interconnections can be used for all components; A different number of wheels can be used on the robot; Legs or “caterpillar tracks” could be substituted for wheels; A mounted battery charger power line connector or docking station may be used in lieu of changing out the batteries; Contact or “bump” sensor(s); Robot cover can be mounted in different ways; Different RF transmitter frequencies can be used; Various non-ferrous metals may be used; Various plastics may be used; Steering could be controlled with a servo; Different frequencies of the electromagnetic spectrum can be used in distance detection devices; Radio detection and ranging (RADAR) can be used; Distances to objects other than the walls could be used to determine relative positioning. The battery can be compartmentalized separately from the other robot components and can have its own access door. A spray tank may be included for the distribution of disinfectant.
[0078] The system can also employ a “triangulation” method using a combination of radio frequency transmitters and receivers placed both within or upon the robot and within or upon the poultry house.
[0079] Alternative and/or supplemental methods of providing positioning guidance data can include SONAR, light beams, and/or bump sensors to accommodate variation in poultry house design and/or grower needs.
[0080] Whatever distance measuring device or combination of devices is/are employed, our invention uses the same basic robot, robot control algorithm, and operational method and the designated time interval at which the robot(s) will walk the poultry while distance measurements are received, interpreted, and robot control maintained in the form of steering and motor commands. | An adaptable and configurable automated, trackless, and self-propelled robot system for agitating the poultry within the corrosive environment of a poultry house. Use of our system will help to maximize poultry growth-to-feed-consumed ratios, as well as save time, effort, and expense for poultry farmers agitating their birds by walking them or having them walked. | 0 |
FIELD OF THE INVENTION
The following invention relates to fire suppression systems and particularly fire suppression systems carried by aircraft, such as for use in fighting wildfires. More particularly, this invention relates to fire suppression gel blenders which mix a gel concentrate with water and systems which mount such fire suppression gel blenders upon an airborne delivery system for delivery of fire suppression gel from fire fighting aircraft and other platforms.
BACKGROUND OF THE INVENTION
In the fighting of wildfires, a variety of fire suppression materials are known, as well as equipment for delivery of such fire suppression materials. Perhaps the most common fire suppression material is liquid water. Water can be delivered on a fire, or a space which is to be treated in advance to stop the progression of a fire, in a variety of different ways. For instance, hoses can deliver water from a stationary source such as a fire hydrant, or from a mobile source such as a fire truck. Water trucks are known which can deliver water from tanks on the vehicle to ground adjacent the vehicle, with or without use of hoses.
Aircraft can also be used for delivery of water for fire suppression. While fixed wing aircraft are sometimes used, most often water is delivered by rotating wing aircraft. In a typical such system, a bucket is suspended from a helicopter. The bucket can be dipped into a water reservoir to fill the bucket. The helicopter then transports the bucket to an area to be treated with the water. A floor or other portion of the bucket is openable to drain the bucket of water and treat the area beneath the bucket. The helicopter then repeats the filling procedure for additional treatment of areas with water. One such line of buckets is provided by S.E.I. Industries, Ltd. of Delta, British Columbia, Canada under the trademark BAMBI BUCKET.
Fire suppression gels are known in the art to have a greater effectiveness in suppressing fire than water alone. Such gels typically begin in the form of a concentrate which can be a solid or a liquid having a high concentration of gel compositions therein. This gel is hydrated to a most desirable water and gel mixture ratio and then is applied to an area to either directly extinguish fire or to treat an area in advance of an approaching fire to impede the progress of the fire, or otherwise suppress fire in the area being treated. Such fire suppression gels, when mixed with water, greatly enhance the effectiveness of the water in suppressing the fire. In particular, the water in the hydrated gel does not evaporate as quickly as water alone, thus maintaining a coating of the area to be treated and discouraging the combustion of combustible materials in the area being treated.
One such fire suppression gel is provided by Ansul Canada Limited of Toronto, Ontario, Canada (dba “Wildfire”) under the trademark AFG FIREWALL in the form of a liquid emulsion.
While the use of such fire suppression gels is known when treating an area with fire hoses either coupled to stationary sources of water or hydrated gel; or from mobile ground sources (such as tanker trucks), a need exists for an effective airborne fire suppression gel delivery system. While a bucket or other container filled with hydrated gel could be utilized, such an arrangement would be inefficient in that frequent return trips to a source of hydrated gel would be required. Accordingly, a need exists for a system for onboard manufacture of such a water and fire suppression gel mixture on an airborne platform.
Furthermore, water buckets and fixed tanks deliver water to an area to be treated for fire suppression in a rather imprecise manner, merely involving the opening of a lower portion of the bucket or tank. While generally effective for water having a lower fire suppression capacity, with the utilization of fire suppression gel is it desirable that a mixture of water and fire suppression gel be applied to an area to be treated in a precise manner to maximize the fire suppression capability of the gel and minimize the number of repeat trips required and maximize the area being treated by an airborne vehicle.
SUMMARY OF THE INVENTION
With this invention a fire suppression gel blender is provided suitable for use in an airborne delivery system to provide high efficiency delivery of fire suppression gel in fire fighting situations, where the urgency of the situation greatly benefits from efficiency and effectiveness of the delivery system. The overall delivery system includes known prior art aircraft, and particularly rotating wing aircraft, as well as water containing buckets for suspension beneath such aircraft or other known water containing structures. With this invention, the aircraft is modified to include a tank of gel concentrate or other gel source. The bucket or other water containing structure is modified to include a fire suppression gel blender assembly adjacent thereto.
This blender assembly includes a water inlet for receiving water contained within the bucket or other container. A combiner adds concentrated fire suppression gel from the source of gel carried by the aircraft, such as by supplying the gel concentrate along a conduit line extending from the aircraft down to the blender assembly within the bucket. A pump is provided, preferably downstream of the water inlet and gel inlet. This pump both pressurizes the water and gel mixture, as well as functioning to enhance the mixing of the water and fire suppression gel mixture.
The pressurized water and fire suppression gel mixture, referred to herein as hydrated gel, is then delivered to a discharge. This discharge is preferably in the form of a nozzle, typically adjacent the bucket and pointed generally downward. When the blender assembly is powered by powering of the pump, the hydrated gel is simultaneously manufactured and sprayed downward from the bucket. The aircraft can be flown at a variable height to adjust a width of lines being treated with fire suppression gel, a process called “striping.” When the aircraft flies lower this line is narrower. When the aircraft flies higher this line is wider. A density with which hydrated gel is applied to the area to be treated can be adjusted by adjusting a speed at which the aircraft travels.
When the supply of water has been depleted, the aircraft returns to a water reservoir to refill the water container such as by dipping the bucket into the water reservoir as is known in the prior art. The aircraft can then be returned to the area to be treated and the system again commences operation. The aircraft most preferably carries a supply of fire suppression gel concentrate which lasts at least an amount of time similar to an amount of time that a fuel supply for the aircraft lasts. In this way, when the aircraft is required to return to a base for refueling, the source of gel concentrate can also be replenished.
While the preferred embodiment of this invention involves the installation of the blender assembly within or adjacent a water containing bucket, as an alternative to such fitting within existing buckets, a separate customized structure could be combined with the blender assembly to function according to this invention. Such an assembly could be suspended below the aircraft or mounted to an underside or other portion of the aircraft, or to some other mobile platform, such as a truck.
While the hydrated gel is preferably delivered from a nozzle having a predictable spray pattern emanating therefrom, other forms of discharges could be provided downstream of the pump. As an alternative, the pump could discharge back into the bucket and the water and fire suppression gel combination could be delivered by opening of the bucket as water alone is currently known to be dispensed from an aircraft borne bucket.
Other details of this invention and various embodiments of this invention are described in conjunction with the further written description of this invention provided below.
OBJECTS OF THE INVENTION
Accordingly, a primary object of the present invention is to provide a fire suppression gel delivery system which can be coupled to an aircraft and spray fire suppression gel onto an area to be treated.
Another object of the present invention is to provide a fire suppression gel delivery system which manufactures fire suppression gel by hydrating gel concentrate onboard a mobile platform immediately before discharge of the hydrated gel onto an area to be treated.
Another object of the present invention is to provide a method for fighting wildfires which involves spraying fire suppression gel in stripes of varying densities and widths upon an area to be defended or directly around the fire perimeter itself.
Another object of the present invention is to provide a method for blending and delivering fire suppression gel from an airborne delivery platform.
Another object of the present invention is to provide a fire suppression gel discharge coupleable to a water containing bucket or other structure and with a water and fire suppression gel blender upstream of the discharge to utilize water from the container to hydrate the fire suppression gel before delivery from the discharge.
Another object of the present invention is to maximize the efficiency with which water is utilized by fire fighters in fighting fires.
Another object of the present invention is to provide a fire suppression gel blender which can be used on mobile platforms to blend water with gel concentrate immediately before spraying.
Another object of the present invention is to provide a method for controlling a width and density of striping of fire suppression gel upon an area to be treated with fire suppression gel.
Other objects of the present invention will become apparent from a careful reading of the included drawing figures, the claims and detailed description of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an environment where the system of this invention is being utilized to provide a fire suppression barrier line between a house and an advancing wildfire according to an embodiment of this invention.
FIG. 2 is a full sectional view of a water bucket containing the gel blender and discharge nozzle coupled thereto, according to the FIG. 1 embodiment of this invention.
FIGS. 3 and 4 are perspective views of the gel blender assembly of an embodiment of this invention shown separate from the bucket or related equipment.
FIG. 5 is a front elevation view of that which is shown in FIGS. 3 and 4 .
FIGS. 6 and 7 are perspective views from alternate perspectives of an outlet nozzle associated with the fire suppression gel delivery system of one embodiment of this invention.
FIG. 8 is a full sectional view of the bucket of FIG. 2 , but shown with water being delivered directly from the bucket in one alternative use according to this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, wherein like reference numerals represent like parts throughout the various drawing figures, reference numeral 10 is directed to a delivery system for manufacture and delivery of fire suppression gel. The delivery system 10 can be mounted within a bucket 20 suspended from an aircraft A. The system 10 discharges fire suppression gel from a nozzle 70 in the form of a spray S of hydrated fire suppression gel. This spray S can form a line L in a process referred to as “striping” to provide a barrier between an advancing fire F and a house H or other structure to be defended.
In essence, and with particular reference to FIG. 2 , basic details of the fire suppression gel blending and delivery system 10 of this invention are described, according to a preferred embodiment. The delivery system 10 and associated blender assembly 30 can be mounted to various different water containing structures, but are most preferably configured in this preferred embodiment to be mounted to a bucket 20 configured to be suspended from an aircraft A, such as a helicopter ( FIG. 1 ).
The blender assembly 30 includes a combiner 40 which is configured to receive water W from the bucket 20 and gel concentrate from a gel reservoir, typically borne by the aircraft A and transported to the combiner 40 along a gel concentrate supply line 32 . The combiner 40 mixes water with the gel concentrate upstream of a pump 50 . The pump 50 pressurizes the now hydrated gel as well as performing a mixing function to thoroughly mix the water W and gel concentrate to form the hydrated fire suppression gel ready for delivery and use in fire suppression. Various interconnect conduits 60 lead from the pump 50 to a nozzle 70 . The nozzle 70 is a preferred form of discharge that includes a spout 80 pointing generally downward to provide the spray S of hydrated gel downward from the aircraft A, or otherwise away from a vehicle carrying the entire delivery system 10 .
More specifically, and with continuing reference to FIG. 2 , details of the bucket 20 for supporting the delivery system 10 of this invention, are described according to this preferred embodiment. While the delivery system 10 of this invention could be mounted to other structures, in this embodiment shown in FIGS. 1-8 , the delivery system 10 is configured to be mounted to a bucket 20 (or other container) which has been configured for fire suppression by dumping water W in an area to be treated.
In particular, the bucket 20 includes side walls 22 extending up from a floor 24 , so that the bucket 20 has a generally cylindrical form. The walls 22 extend approximately vertically while the floor 24 extends approximately horizontally. A suspension assembly 28 , also referred to as a “spider” holds open an upper end of the bucket 20 defined by a lip 26 . Suspension lines 29 are coupled to the bucket 20 and extend up to an aircraft A ( FIG. 1 ) such as a helicopter.
The bucket 20 is configured so that it can be dipped into a water reservoir, such as a river, pond, lake or the ocean. The bucket 20 falls over sideways and water pours into the bucket. Once the bucket 20 is full, the aircraft A can lift up and carry the water to an area to be treated. The floor 24 is coupled to an aperture control line 25 and an aperture in the floor 24 can be opened by pulling on the aperture control line 25 ( FIG. 8 ). This aperture control line 25 typically extends up to the aircraft A so that both suspension of the bucket 20 and control of the aperture in the floor 24 of the bucket 20 are provided from the aircraft A.
With this invention, the aperture in the floor 24 of the bucket 20 is typically not used. Rather, the blender assembly 30 fits within the bucket 20 and pumps water out of the bucket 20 and hydrated gel is sprayed from the delivery system 10 mounted on the bucket 20 . Typically, the aperture control line 25 would not be disabled when utilizing the bucket 20 with the delivery system 10 of this invention. Thus, should it be desired to dump remaining water W from the bucket 20 , such as after fire suppression gel concentrate has been depleted, the aperture control line 25 can still be utilized to open the floor 24 and allow release of water W from the bucket 20 .
As an alternative to the bucket 20 , the aircraft A can be fitted with fixed tanks for containing water. Such tanks are known which are filled by a snorkel pump extending down from the aircraft A and dipped into a water reservoir, such as a pond, lake or river. The blender assembly 30 would be installed within such a tank or adjacent thereto with access to water from the tank. The blender assembly in such a fixed tank embodiment could be within or adjacent the tank. As another alternative, the snorkel pump could be replaced by the blender assembly 30 appropriately modified. In such an embodiment, the pump motor 58 would be sized to lift the water up the snorkel to the tank. Gel concentrate could be added to the pump so that the fixed tank stores hydrated gel.
With continuing reference to FIG. 2 , as well as FIGS. 3-5 , details of the blender assembly 30 of the delivery system 10 of the preferred embodiment are described. This blender assembly 30 is shown mounted within the bucket 20 , but could alternatively be located within a tank of water W mounted to either an aircraft A or some other mobile or stationary platform. The blender assembly 30 could be permanently affixed to the bucket 20 or integrally formed within the bucket 20 , but most preferably is removably attachable to the bucket 20 so that the blender assembly 30 can be moved from one bucket 20 to another bucket 20 when desired. Attachment of the blender assembly 30 to the bucket 20 is sufficiently adapted to work with the bucket 20 so that the bucket 20 does not require modification and is not damaged or altered by removal of the blender assembly 30 from the bucket 20 .
The blender assembly 30 includes a series of lines which supply power and materials for utilization of the blender assembly 30 . In particular, a gel concentrate supply line 32 extends from the blender assembly 30 to a source of gel concentrate. Typically this source of gel concentrate is adjacent the aircraft A, such as in a tank mounted to or carried within or under the aircraft A (see broken lines in FIG. 1 generally depicting such a tank). Thus, the gel supply line 32 typically extends vertically up from the blender assembly 30 within the bucket 20 up to the aircraft A. Hydraulic lines 34 are preferably utilized to power a hydraulic motor which drives the pump 50 . The hydraulic lines 34 preferably include a supply and return line bundled together and also extend up to the aircraft A where pressurized hydraulic fluid from the aircraft A can be utilized to drive the motor 58 of the pump 50 . Typically, also a color dye line 75 extends down to the bucket 20 from the aircraft A. The color line 75 supplies a colorant which can be added to the hydrated gel before being sprayed from the discharge, such as in the form of the nozzle 70 , so that areas that have been treated can more easily be seen.
The blender assembly can include a mounting bracket 36 for attachment of the blender assembly 30 to adjacent structures or for mounting of auxiliary equipment to the blender assembly 30 . Preferably, a plate with a bungee hole 35 therein is provided as part of the blender assembly 30 . A bungee cord or other line can pass through this bungee hole 35 and secure the blender assembly 30 to a side of the bucket 20 so that the blender assembly 30 is prevented from flopping around too much within the bucket 20 .
A hose support arch 38 is configured along with the blender assembly 30 which is generally in the form of a truss and helps to hold an outlet hose from the blender assembly 30 relative to other portions of the blender assembly 30 . The hose support arch 38 is carried at an upper end by a spider tube 36 which can have a leg of the spider assembly 28 passing therethrough so that the entire blender assembly 30 can be suspended from one of the spider legs of the suspension assembly 28 . The hose support arch 38 extends down from this spider tube 39 and various different portions of the blender assembly 30 are carried by the hose support arch 38 .
Preferably, the spider tube 39 is coupled to the hose support arch 38 through a pivotable connection, such as with a series of concentric tubes with a pin passing therethrough and with cotter pins to capture this pin within these co-linear tubes. One of the tubes has the spider tube 39 coupled thereto, one of these tubes is at an upper end of the hose support arch 38 and one of these tubes is coupled to an upper elbow 66 of interconnect conduits 60 that join the blender assembly 30 to the nozzle 70 . The pivotable attachment of these parts together allows for the blender assembly 30 to pivot somewhat to a desired position and accommodate slightly different geometries for the side walls 22 of the bucket 20 and otherwise avoid damage when bumping or jostling of the blender assembly 30 occurs, such as during dipping of the bucket 20 to fill the bucket 20 with water W.
The blender assembly 30 generally includes a combiner 40 and a pump 50 . The combiner 40 provides the basic function of bringing together water W and gel concentrate for hydrating of the gel concentrate to form the fire suppression gel to be utilized by the delivery system 10 of this invention. The combiner 40 is generally in the form of a “T” junction conduit 48 that allows two pathways to come together to form a single pathway. In this most preferred embodiment, this combiner 40 includes a gel inlet conduit 42 and a water inlet 44 . A debris preclusion screen 46 is preferably provided surrounding the water inlet 44 . The junction conduit 48 acts to bring the gel concentrate inlet conduit 42 together with the water inlet 44 and join the water W with the gel concentrate to allow for hydration of the gel concentrate. This junction conduit 48 is preferably provided upstream of the pump 50 on a suction side of the pump 50 .
The pump 50 includes an inlet 52 and outlet 56 . Both the inlet 52 and outlet 56 are joined to an impeller housing 54 therebetween. The motor 58 drives an impeller within the housing 54 between the inlet 52 and the outlet 56 . A drive sleeve 59 extends between the motor 58 and the impeller housing 54 to space the motor from the impeller housing 54 .
The pump 50 in this preferred embodiment is a centrifugal pump. In one embodiment the pump 50 has a flow rate of 400 gallons per minute. The impeller includes a series of vanes which rotate and change the fluid from extending axially at the inlet 52 to extending circumferentially at the outlet 56 , by action of the impeller blades on the fluid within the housing 54 . By providing the pump 50 at least as a dynamic style pump, and most preferably as a centrifugal pump, the impeller blades of such a dynamic pump 50 both act to pressurize the hydrated gel, but also act to promote mixing of the water with the gel concentrate to form the hydrated gel as a substantially homogeneous mixture. While less desirable, a positive displacement pump, such as a piston pump, could also conceivably be utilized.
Hydraulic fluid is supplied from the aircraft A down the hydraulic lines 34 to drive the motor 58 . The motor 58 in turn causes the impeller to move within the impeller housing 54 so that the pump 50 causes water to be drawn into the pump 50 . A typical flow rate for the pump 50 is four hundred gallons per minute, but could be scaled to meet the capacity of the aircraft and the needs of the user. If beneficial, multiple blender assemblies 30 could be used in parallel to optimize such scaling of this technology. While the motor 58 is disclosed as a hydraulic motor, an electric motor could alternatively be utilized, or conceivably an internal combustion motor.
The water W mixes with the gel concentrate to form hydrated gel which then passes out of the outlet 56 of the pump 50 . Because the motor 58 is a hydraulic motor, it is inherently submersible without complex seals being required. By placing the pump 50 downstream of the combiner 40 the pump 50 pulls the water W into the inlet 44 and pulls gel concentrate into the gel inlet 42 . To ensure the proper gel concentrate to water mixture ratio, the gel concentrate is preferably supplied by a positive displacement pump, such as a gear pump. The speed of this gear pump is preferably adjustable to meet the needs of the user. Such speed adjustment in turn modifies the hydrated gel viscosity.
While the hydrated gel could conceivably be delivered to some form of storage vessel, most preferably the hydrated gel is immediately utilized after manufacture by the blender assembly 30 . In particular, interconnect conduits 60 are provided to direct the hydrated gel from the outlet 56 of the pump 50 to the nozzle 70 . These interconnect conduits 60 include a lower elbow 62 adjacent the impeller housing 54 which converts the hydrated gel from traveling horizontally to traveling vertically adjacent the pump 50 . A riser hose 54 then extends up from the lower elbow 62 up to a top of the bucket 20 . An upper elbow 66 is coupled to the riser hose 64 and transitions the flow of the hydrated gel from vertical travel to substantially horizontal travel. The upper elbow 66 is preferably pivotably coupled to the suspension assembly 28 of the bucket 20 along with the spider tube 39 and hose support arch 38 . A lateral hose 68 extends from the upper elbow 66 across a top of the bucket 20 , typically from one side of the bucket 20 to an opposite side of the bucket 20 . The interconnect conduit 60 terminates at the nozzle 70 where the lateral hose 68 joins with the inlet elbow 72 of the nozzle 70 .
With particular reference to FIGS. 6 and 7 , details of the nozzle 70 , providing a preferred form of discharge for the hydrated gel, is described according to this preferred embodiment. The nozzle 70 acts to direct the hydrated gel downward for treatment of an area below the aircraft A, or otherwise function to direct the hydrated gel from the blender assembly 30 to an area to be treated. The nozzle 70 begins with an inlet elbow 72 which redirects the hydrated gel from traveling horizontally to traveling downward typically substantially vertically.
A support bracket 74 includes an inner plate 76 parallel with and opposite an outer plate 78 . The inner plate 76 and outer plate 78 are spaced apart sufficient to allow them to straddle the lip 26 of the bucket 20 so that the support bracket 74 can merely rest upon the lip 26 of the bucket 20 with the nozzle 70 outboard of the bucket 20 . If desired, mechanical fasteners can also be utilized.
The inlet elbow 72 is coupled to a spout 80 of the nozzle 70 . This spout 80 is typically a generally rectangularly cross-sectioned elongate tube extending from the inlet elbow 72 down to an outlet 82 . The outlet 82 and associated spout 80 have a shape which cause the hydrated gel to exit the nozzle 70 as a spray S which is generally in the form of a fan having a substantially constant thickness and diverging width ( FIG. 1 ).
A width of a lower end of this fan of the spray S can be controlled by adjusting the elevation of the aircraft A. As an alternative, the spout 80 could be attached to other portions of the nozzle 70 through a quick connect coupling and different spouts 80 could be substituted for each other to change spray patterns for the spray S discharged from the nozzle 70 .
Most preferably, a color port 73 is provided adjacent the inlet elbow 72 . A color line 75 is coupled to this color port 73 . A source of colorant, such as a colored dye liquid is preferably supplied onboard the aircraft A or adjacent the aircraft A. This source is preferably delivered by a gear pump or other adjustable positive displacement pump. This pump mixes an appropriate amount of colorant to the hydrated gel. In this way, the hydrated gel is colorized and a line L of hydrated gel ( FIG. 1 ) that has been applied to the treatment area can be readily visually identified.
The striping technique disclosed herein can be performed from aircraft fitted with fixed tanks or a bucket with appropriate modification of mounting hardware. The striping technique could be used with hydrated gels of various concentrates, and also could be used with water only if desired. This disclosure is provided to reveal a preferred embodiment of the invention and a best mode for practicing the invention. Having thus described the invention in this way, it should be apparent that various different modifications can be made to the preferred embodiment without departing from the scope and spirit of this invention disclosure. When structures are identified as a means to perform a function, the identification is intended to include all structures which can perform the function specified. When structures of this invention are identified as being coupled together, such language should be interpreted broadly to include the structures being coupled directly together or coupled together through intervening structures. Such coupling could be permanent or temporary and either in a rigid fashion or in a fashion which allows pivoting, sliding or other relative motion while still providing some form of attachment, unless specifically restricted. | The delivery system includes a blender assembly which can be fitted within a bucket or other container an aircraft. The blender assembly includes a combiner which receives water from within the container and gel concentrate from a gel inlet. The combiner brings the water and gel concentrate together upstream of a pump. The pump pressurizes and mixes the water and gel concentrate together to provide a hydrated fire suppression gel ready for application. An outlet of the pump leads through appropriate conduits to a nozzle. The nozzle includes a downwardly extending spout which sprays the hydrated gel down onto the ground beneath the aircraft. When the water within the container has been depleted, the aircraft is flown to a water source and the container is refilled. Then the blender can again be used to manufacture and deliver the fire suppression gel to an area to be treated. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 12/943,974, filed Nov. 11, 2010, which is a divisional of U.S. patent application Ser. No. 11/814,342, filed Jul. 19, 2007, now U.S. Pat. No. 7,850,562, issued Dec. 14, 2010, which is a National Phase Patent Application of PCT/US2006/002013, filed Jan. 19, 2006, which claims the benefit of U.S. Provisional Patent Application No. 60/593,493, filed Jan. 19, 2005, all of which are incorporated herein in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to endless belts for conveyors and, more particularly, to thermoplastic, toothed endless belts driven by pulleys.
[0004] 2. Description of the Related Art
[0005] Low tension, direct drive conveyor belts are often used in situations where hygiene and cleanliness are critically important. For example, in food processing plants such as those that process meat products for human consumption, low tension, direct drive belt conveyors are used to transport items. Sanitation is critically important and, therefore, the endless belts used in such conveyors are conventionally made of materials that can be hygienically cleaned.
[0006] It is known to use thermoplastic belts with a smooth continuous surface on one side and teeth on the other side adapted to engage grooves or sheaves in a drive pulley, as shown for example in U.S. Pat. No. 5,911,307. But such a thermoplastic belt has characteristics of both a flat, stretchable belt that might be typically driven by a friction pulley, and a toothed belt driven by a drive pulley. These characteristics reflect the two basic ways that a drive pulley can transmit torque to the belt. In a flat belt, torque is transmitted to the belt through friction between the drive pulley surface and the adjacent surface of the belt. The effectiveness of this type of drive is a function of belt tension (both initial pretension and the tension generated due to the product load) and the coefficient of friction of the material of the belt surface and the material of the pulley surface. A friction driven flat belt is subject to contaminants that can affect the coefficient of friction. Moreover, elongated belts typically stretch over time and under load and such stretching can affect its tension. A thermoplastic belt in particular can stretch 3% of its length or more.
[0007] For these reasons, direct drive belts are preferred in such facilities as food handling operations. In an ideal toothed belt, torque is transmitted to the belt through the contact of a face of a tooth or recess on the pulley to a face of a tooth or recess on the belt. But the use of a thermoplastic toothed belt as a direct drive belt with a pulley introduces problems, primarily because of the elasticity of the belt.
[0008] Because a thermoplastic belt stretches under load, the belt teeth may not always mate with the pulley recesses or sheaves as the belt wraps around the pulley. Prior solutions have determined that the tooth pitch of the belt must be less than the pitch of the drive pulley at less than maximum elongation of the belt. Also, the pulley pitch must equal the pitch of the belt at maximum elongation, give or take a fraction of a percent. Moreover, to ensure that the belt teeth are positioned to enter the pulley sheaves, the width of each sheave in the pulley must exceed the belt tooth width at least by the amount of distance generated by elongating the belt the maximum allowable amount over the span of the belt wrap.
[0009] Yet problems remain in ensuring that the belt teeth stay engaged with the pulley sheaves over the full range of belt elongation and load in the field. Due to the necessary pitch difference between the belt and the pulley, only one belt tooth will be driven by a pulley sheave at any given moment. It has been found that this engaged tooth is always the tooth that is about to exit the pulley. For all subsequent belt teeth that engage the pulley sheaves at any given moment, there is a gap between the face of the belt tooth and the face of the pulley sheave, and that gap progressively increases in size for each successive tooth. The size of these gaps are a function of belt tension, in that each respective gap is largest when the belt has minimum tension and smallest when the belt is at maximum tension. If the belt tension exceeds a predetermined maximum, the entry tooth will no longer sit properly in the pulley sheave and effective drive characteristics will be lost. In other words, the pulley may rotate while the belt slips until a tooth engages again.
[0010] It can be seen that as the exiting tooth disengages from the drive pulley there remains some amount of gap between the following belt tooth and the face of its respective pulley sheave. Therefore, discounting any momentum of the belt and any friction between the belt and the pulley, the belt will effectively stop for a brief moment until the following sheave re-engages the new “exit tooth”. For this brief moment no torque is transmitted from the pulley to the belt and thus the belt speed is temporally retarded.
[0011] This motion causes a slight amount of vibration and noise in the system. Vibration increases in frequency as pulley tooth pitch is reduced and/or pulley rotation speed is increased. It may be nearly undetectable in belt applications with a small tooth pitch and a large amount of mass for damping, such as when large product loads approach a predetermined maximum for belt elongation. But for many applications, particularly where loads are light and/or belt speed is slower, the resultant vibration and noise may be unacceptable.
[0012] Nevertheless some slip between the belt and the pulley is what enables a direct drive application to work. This temporary disengagement of belt teeth from pulley sheaves causes the average belt speed to be less than the average pulley speed. In fact, the average belt speed is less than the pulley speed by the percentage of elongation that is still available in the belt (max elongation−current elongation). Because of this necessary slip, any characteristics of a flat belt drive will compromise the benefits of direct drive, e.g. friction. Friction between the belt and the pulley will retard slippage and may cause the trailing tooth to miss the pulley sheave altogether.
[0013] Another problem occurs when the belt is under virtually no tension. In some application such as a horizontally positioned conveyor, the weight of the lower span of the belt tends to pull the teeth at the exit point out of the respective pulley sheave. The critical area of belt wrap around the pulley is the short distance between the exit point and one pulley sheave pitch back. If the belt tooth remains engaged through this arc then proper drive will be achieved, but if not, belt teeth will “pop” and the driving dynamics will become uncontrolled.
SUMMARY OF THE INVENTION
[0014] In one, a direct drive conveyor includes an endless belt and one or more drive pulleys. The belt or the drive pulley has teeth at a given pitch and the other of the belt or the drive pulley has recesses at a different pitch such that the pulley pitch is greater than the belt pitch. The recesses are adapted to receive the teeth as the belt wraps around the drive pulley to an exit point. The conveyor also includes means to minimize friction between the belt and the drive pulley wherein only one tooth or recess on the belt at a time is driven by a corresponding drive recess or tooth on the drive pulley so that the belt can slip relative to the drive pulley after the driven tooth or recess on the belt exits its corresponding drive recess or tooth on the drive pulley at the exit point. The conveyor also includes an idler spaced from the at least one drive pulley wherein the idler is a stationary disk that bears against the belt.
[0015] Another aspect is a method of driving an endless belt in a conveyor having one drive pulleys. The belt or the drive pulley has teeth and the other of the belt or the drive pulley has recesses adapted to receive the teeth as the belt wraps around the pulley to an exit point. The drive pulley and the belt having different pitches such that the pulley pitch is greater than the belt pitch. The method includes causing the drive pulley to rotate so that only one tooth or recess on the belt at a time is driven by a corresponding drive recess or tooth on the drive pulley, enabling the belt to move at an average speed less than the average speed of the drive pulley, and providing minimal friction between the belt and the drive pulley to enable the belt to slip relative to the drive pulley when the drive tooth is disengaged from the drive sheave.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In the drawings:
[0017] FIG. 1 is a perspective side view of a prior art belt installed between two pulleys;
[0018] FIG. 2 is an enlarged view in elevation of a portion of FIG. 1 ;
[0019] FIG. 3A is a view similar to FIG. 2 showing a conveyor according to the invention;
[0020] FIG. 3B is a view similar to FIG. 3 showing another aspect of a conveyor according to the invention;
[0021] FIG. 3C is an end view of the drive pulley of FIG. 3A ;
[0022] FIG. 3D is an enlarged cross sectional view of a portion of the belt in FIG. 3A ;
[0023] FIG. 4 is a view of a center drive belt system according to the invention;
[0024] FIG. 5 is a fractional side view of a belt and pulley showing an alternative sheave construction according to the invention;
[0025] FIG. 6 is a fractional perspective view of one embodiment of an idler according to the invention; and
[0026] FIG. 7 is a view similar to FIG. 3 showing another aspect of a conveyor according to the invention.
DETAILED DESCRIPTION
[0027] Some problems with known thermoplastic direct drive belts are shown in a direct drive conveyor 50 of FIGS. 1 and 2 . An endless belt 100 is seen in FIG. 1 in a typical installation between two pulleys 102 and 103 . The pulleys 102 , 103 are conventional and they can be any of a number of different forms and sizes. Each pulley 102 or 103 has a number of transverse grooves or sheaves 104 spaced around its circumference. Each sheave 104 has a driving face 105 and an opposed, non-driving face 107 . The belt 100 has a plurality of teeth 106 equidistantly spaced from each other on the inside surface 108 of the belt, each tooth having a driving surface 109 . The teeth 106 engage the sheaves 104 of each pulley as the belt wraps around the pulley. At least one pulley, e.g. pulley 102 , is a drive pulley; the other 103 can be an idler or slave pulley. In this configuration, the upper span of the belt will carry loads as the belt 100 travels in the direction of arrow 111 . The belt 100 has an outside surface 110 that is fairly smooth and free of discontinuities, typically made of a thermoplastic material such as Pebax® resin, polyester or polyurethane.
[0028] The belt 100 has a pitch 112 defined as the distance between the centerlines of adjacent teeth 106 . The belt pitch 112 is measured along a belt pitch line 114 , which corresponds to the neutral bending axis of the belt. As the belt 100 bends around the pulley 102 , the neutral bending axis is that imaginary plane on one side of which the belt material is under compression and on the other side of which the belt material is under tension.
[0029] Similarly, the pulley pitch 116 is the arc length between the centerlines of adjacent sheaves 104 , measured along the pulley's pitch circle 118 . The pulley pitch circle 118 in this case corresponds to the belt pitch line 114 as the belt 100 wraps around the pulley 102 . In other words, the pulley pitch circle 118 will have the same radius as the belt pitch line 114 as the belt wraps around the pulley.
[0030] As noted above, the exit tooth 120 will be the drive tooth as its driving surface 109 contacts the driving surface 105 of the sheave 104 that has received the exit tooth. The trailing tooth 122 nests in its corresponding sheave 104 , but there is a gap 124 between the tooth driving surface 109 and the sheave driving surface 105 . Also, the pulley surface 123 between adjacent sheaves may engage the surface 128 of the belt 100 between adjacent teeth 106 . The problems arising from this structure are explained above. Friction between the surface 126 on the pulley and the surface 128 on the belt adds a force component that interferes with the relative movement between the belt and the pulley, possibly causing the teeth not to engage the appropriate sheaves on the pulley. And any friction is enhanced when the belt is placed under tension. The normal and customary response in the field to a belt slipping on the pulley is to increase tension. But this serves only to render the direct drive ineffective. On the other hand, when the belt is under no tension, and the conveyor is horizontal, the weight of the lower belt span tends to pull the driven tooth from its pulley sheave prematurely, adversely affecting the direct drive dynamics.
[0031] One aspect of the invention is shown in FIGS. 3 a - 3 c where a direct drive conveyor 129 has all the structure of the prior art system shown in FIGS. 1 and 2 , plus characteristics of the invention. Accordingly, components in the inventive conveyor that are the same as components in the prior art conveyors of FIGS. 1 and 2 bear like references. In one aspect of the invention, the pulley and belt are designed to permit minimal friction between them. The surface 130 of the belt between adjacent teeth, and optionally including the teeth 106 , can be coated with a friction reducing material 132 , e.g. polytetrafluoroethylene (PTFE), also known as Teflon®. In addition, or alternatively, the surface 134 between adjacent sheaves on the pulley can be coated with a friction reducing material. As well, the pulley will preferably have minimal surfaces contacting the belt anywhere but on the belt tooth surfaces. For example, the supporting structure such as the surface 136 between adjacent sheaves can be recessed from the perimeter of the pulley as shown in FIG. 3 b . It can also have a narrower neck 138 to reduce surface contact with the belt (See FIG. 3 c ).
[0032] Another aspect of the invention pertains primarily to any application where the span exiting the drive pulley tends to pull the driven tooth from the drive sheave. The most common situation would be where the belt is run horizontally and the weight of the return span of the belt exiting the drive pulley tends to form a catenary curve, and consequently tends to urge the driven tooth out of the drive sheave prematurely, i.e., before an optimum exit point 170 as shown in FIG. 2 . If top dead center 140 is defined as a point of rotation of the pulley where a sheave 104 is centered on a line extending from the center 142 of the pulley, then the optimum exit point 170 is preferably when the drive sheave on the pulley is on a line slightly more than 180° from top dead center in the direction of rotation. As shown in FIGS. 3 a and 3 b , a position limiter 200 is disposed near the exit point 170 , i.e., the point where the exit tooth 120 of the belt optimally leaves the corresponding sheave of the pulley. One preferred location, as shown in FIG. 3 b , places the position limiter 200 adjacent the pulley at the exit point 170 of the belt tooth. One alternative location, as shown in FIG. 3 a , includes a position limiter 200 ′ just past the exit point 170 . In this case, the position limiter deflects the belt enough to ensure that the tooth does not prematurely exit the sheave. Other alternative locations, shown in phantom) are at 200 ″ immediately prior to the exit point 170 and 200 ′″ at the next succeeding tooth 122 . Preferably, the position limiter 200 will be disposed in such a manner that the belt can not lift off the pulley more than 25% of the tooth height until the exit point 170 .
[0033] The position limiter 200 can be a belt-width roller, as shown, or it can be multiple rollers, such as a pair with one on each edge of the belt. Alternatively the position limiter can be one or more arms or points bearing against the belt, preferably with friction reducing wear pads. Further, the position limiter can be a scraper bar bearing against the belt that will serve two functions, to wit: maintaining the exit tooth within the sheave of the pulley and cleaning the belt as it exits the pulley. The position limiter 200 need not extend across the belt. It need only be positioned to maintain the belt against the pulley or pulleys until the driven tooth is timely released from the respective sheave.
[0034] An alternative embodiment of a direct drive thermoplastic belt conveyor, according to the invention, is shown in FIG. 4 . The system has a center drive pulley 202 and two idler pulleys 204 , 206 with an endless belt 208 . In accordance with the invention, two position limiters 210 , 212 are used with the drive pulley 202 . One limiter 210 is placed near the entry point 214 where the belt tooth enters engagement with the pulley sheave. The other limiter 212 is placed near the exit point 216 . Preferably, the belt wrap is minimized such that only three teeth are wrapped at any time.
[0035] A center drive such as this solves the problems associated with any “flat belt drive” component of the system, such as might be caused by friction between the belt an the pulley for example. As explained above, friction can cause the belt entry tooth to advance relative to the pulley tooth and thus “skip”. This might occur, for example, when the friction force between the belt and the pulley generates a higher speed component than the driving force of the tooth drive surface against the pulley drive surface. Minimizing the amount of wrap also tends to reduce the opportunity for friction between the belt and the pulley.
[0036] It has been found that if any of the pulleys are not drive pulleys, the speed of the idler pulley can cause problems. The drive pulley is generally traveling at a greater speed than the belt speed. If the same geometry was used for the idler pulley as the drive pulley then, for proper tooth engagement, the idler pulley would have to travel at the same speed as the drive pulley. But the idler pulley cannot travel any faster than the belt, inasmuch as the belt drives the idler pulley. Therefore the idler pulley must have a different pitch than the drive pulley (different geometry). Preferably, the idler pulley pitch will be less than or equal to the pitch of an un-tensioned belt. Consequently, as the belt pitch changes with elongation, the idler pulley will be compelled to go slower than the belt. Just as in the drive pulley, the width of the sheaves must exceed the belt tooth width such that there is enough gap to allow for the added length of belt that will occur at the maximum belt tension over the span of belt wrap.
[0037] The idler pulley will primarily be driven as by a flat belt because of its low drag characteristics. This will cause the entry tooth on an elongated belt to not ideally engage a sheave on the idler pulley. To overcome this problem, the coefficient of friction must be minimized as explained earlier. In addition, the angle of the tooth contact face can be designed such that at maximum elongation of the belt, the tip of the belt tooth will contact the pulley sheave driving surface at some point. This will allow the belt tooth to slowly engage the pulley sheave while slowing the idler pulley down until the proper engagement is made. An example is shown in FIG. 5 where an idler pulley 300 is driven by a belt 302 . Sheaves 304 in the pulley 300 are driven by teeth 306 on the belt 302 . To ensure that each tooth 306 properly engages the corresponding sheave 304 , the side of the sheave has two walls at different angles. The lower wall portion 308 is at a steeper angle than the upper wall portion 310 . Preferably, the upper wall portion is at an angle wider than the angle of the belt tooth 306 . This works since the added distance that must be accommodated is only generated over the span of one tooth pitch for the previous tooth will have already engaged the idler.
[0038] Another option shown in FIG. 6 is for an idler 320 to comprise a stationary disk 322 or arm that the belt simply slides against. Preferably, the portion of disk 322 bearing against the belt is covered with a friction reducing coating as set forth above. While this structure may increases friction somewhat between the belt and the idler, it is of little consequence since there is no toothed drive between the belt and the idler. To accommodate these disks longitudinal grooves 324 are provided through the teeth on the toothed side of the belt at set increments to enable the belt to move smoothly over the stationary disks. Using these disks eliminates the complications of idler pulley geometry as well as functioning as effective tracking devices. Further, by being stationary the belt will not have a tendency to “climb up” these disks as it would if the smooth pulleys were rotating.
[0039] It is known for belts to sometimes be fitted with cleats extending upwardly from the smooth surface to help retain or separate objects on the belt. In such an application, the invention contemplates using the cleats to advantage as a position limiter. FIG. 7 illustrates one such application. An endless thermoplastic belt 400 has teeth 402 on one side and cleats 404 on the other side. The belt teeth 402 are sequentially driven by recesses or sheaves 406 on a drive pulley 408 . A position limiter 410 comprises a shoe 412 having an inner curved surface 414 . At least a portion of the curved surface is disposed near the optimum exit point 416 so that the shoe bears against the cleats, which, in turn, urge the belt against the pulley 408 to keep the driven tooth 402 engaged to the exit point.
[0040] While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit. For example, instead of teeth on the belt and sheaves on the pulley, the belt can have holes or recesses and the pulley can have teeth or pins in the manner of a sprocket to engage the holes or recesses in the belt, and the principles of the present invention equally apply. | A thermoplastic endless belt has a smooth outer surface substantially free of discontinuities and an inner surface with a plurality of teeth at a given belt pitch. The teeth are adapted to engage a pulley with circumferentially spaced sheaves at a pulley pitch greater than the belt pitch. The belt is slightly stretchable so that the pulley can drive the endless belt when engaging the teeth within a range of load on the belt. Means are provided to minimize friction between the belt and the drive pulley. Also, a position limiter ensures that the driven tooth stays engaged optimally with the drive sheave. | 5 |
This is a continuation of application Ser. No. 08/168/815, filed Dec. 16, 1993, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to voice compression and more particularly to a system and method for performing voice compression in a way which will increase the overall compression between the incoming analog voice signal and the resulting digitized voice signal.
Prerecorded or live human speech is typically digitized and compressed (i.e. the number of bits representing the speech is reduced) to enable the voice signal to be transmitted over a limited bandwidth channel over a relatively low bandwidth communications link (such as the public telephone system) or encrypted. The amount of compression (i.e., the compression ratio) is inversely related to the bit rate of the digitized signal. More highly compressed digitized voice with relatively low bit rates (such as 2400 bits per second, or bps) can be transmitted over relatively lower quality communications links with fewer errors than if less compression (and hence higher bit rates, such as 4800 bps or more) is used.
Several techniques are known for digitizing and compressing voice. One example is LPC-10 (linear predictive coding using ten reflection coefficients of the analog voice signal), which produces compressed digitized voice at 2400 bps in real time (that is, with a fixed, bounded delay with respect to the analog voice signal). LPC-10e is defined in federal standard FED-STD-1015, entitled "Telecommunications: Analog to Digital Conversion of Voice by 2,400 Bit/Second Linear Predictive Coding," which is incorporated herein by reference.
LPC-10 is a "lossy" compression procedure in that some information contained in the analog voice signal is discarded during compression. As a result, the analog voice signal cannot be reconstructed exactly (i.e., completely unchanged) from the digitized signal. The amount of loss is generally slight, however, and thus the reconstructed voice signal is an intelligible reproduction of the original analog voice signal. LPC-10 and other compression procedures provide compression to 2400 bps at best. That is, the compressed digitized speech requires over one million bytes per hour of speech, a substantial amount for either transmission or storage.
SUMMARY OF THE INVENTION
This invention, in general, performs multiple stages of voice compression to increase the overall compression ratio between the incoming analog voice signal and the resulting digitized voice signal over that which would be obtained if only a single stage of compression were to be used. As a result, average compression rates less than 1920 bps (and approaching 960 bps) are obtained without sacrificing the intelligibility of the subsequently reconstructed analog voice signal. Among other advantages, the greater compression allows speech to be transmitted over a channel having a much smaller bandwidth than would otherwise be possible, thereby allowing the compressed signal to be sent over lower quality communications links which will result in a reduction of the transmission expense.
In one general aspect of this concept, a first type of compression is performed on a voice signal to produce an intermediate signal that is compressed with respect to the voice signal, and a second, different type of compression is performed on the intermediate signal to produce an output signal that is compressed still further.
Preferred embodiments include the following features.
The first type of compression is performed so that the intermediate signal is produced in real time with respect to the voice signal, while the second type of compression is performed so that the output signal is delayed with respect to the intermediate signal. The resulting delay between the voice signal and the output signal is more than offset, however, by the increased compression provided by the second compression stage.
The first type of compression is "lossy" in that it causes at least some loss of information contained in the intermediate signal with respect to the voice signal. Preferably, the second type of compression is "lossless" and thus causes substantially no loss of information contained in the output signal with respect to the input signal.
The intermediate signal is stored as a data file prior to performing the second type of compression. The output signal can be stored as a data file, or not. One alternative is to transmit the output signal to a remote location (e.g., over a telephone line via a modem or other suitable device) for decompression and reconstruction of the original voice signal.
The output signal is decompressed (i.e. the number of bits per second representing the speech is increased) by applying the analogs of the compression stages in reverse order. That is, the output signal is decompressed to produce a second intermediate signal that is expanded with respect to the output signal, and then further decompression is performed to produce a second voice signal that is expanded with respect to the second intermediate signal. The compression and decompression steps are performed so that the second voice signal is a recognizable reconstruction of the original voice signal. The first stage of decompression will produce a partially decompressed intermediate signal that is substantially identical to the intermediate signal created during compression.
Preferably, several signal processing techniques are applied to the intermediate signal to enhance the amount of compression contributed by the second type of compression.
For example, the intermediate signal produced by the first type of compression includes a sequence of frames, each of which corresponds to a portion of the voice signal and includes data representative of that portion. Frames that correspond to silent portions of the voice signal (which are almost invariably interspersed with periods of sounds during speech) are detected and replaced in the intermediate signal with a code that indicates silence. The code is smaller in size than the frames. Thus, replacing silent frames with the code compresses the intermediate signal.
Another way in which the compression provided by the second stage is enhanced is to "unhash" the information contained in the frames of the intermediate signal. Voice compression procedures (such as LPC-10) often "hash" or interleave data that represents one voice characteristic (such as amplitude) with data representative of another voice characteristic (e.g., resonance) within each frame. One feature of one embodiment of the invention is to reverse the hashing so that the data for each characteristic appears together in the frame. Thus, sequences of data that are repeated in successive frames can be more easily detected during the second type of compression; often the repeated sequences can be represented once in the output signal, thereby further enhancing the total amount of compression.
In addition, data that does not represent speech sounds are removed from each frame prior to performing the second type of compression, thereby improving the overall compression still further. For example, data installed in each frame by the first type of compression for error control and synchronization are removed.
Yet another technique for augmenting the overall compression is to add a selected number of bits to each frame of the intermediate signal to increase the length thereof to an integer number of bytes. (Obviously, this feature is most useful with compression procedures, such as LPC-10 which produce frames having a non-integer number of bytes--54 bits in the case of LPC-10.) Although the length of each frame is temporarily increased, providing the second type of compression with integer-byte-length frames allows repeated sequences of data in successive frames to be detected relatively easily. Such redundant sequences can usually be represented once in the output signal.
In another aspect of the invention, compression is performed on a voice signal that includes speech interspersed with silence by performing compression to produce a signal that is compressed with respect to the voice signal, detecting at least one portion of the compressed signal that corresponds to a portion of the voice signal that contains substantially only silence, and replacing the silent portion with a code that indicates silence.
Speech often contains relatively large periods of silence (e.g., in the form of pauses between sentences or between words in a sentence). Replacing the silent periods with silence-indicating code (or other periods of repeated sounds with a similar code) dramatically increases compression ratio without degrading the intelligibility of the subsequently reconstructed voice signal. The resulting compressed signal thus requires either less time for transmission or a smaller bandwidth for transmission. If the compressed signal is stored, the required memory space is reduced.
Preferred embodiments include the following features.
The second compression step can be omitted where repetitive periods are replaced by a code. Silent periods are detected by determining that a magnitude of the compressed signal that corresponds to a level of the voice signal is less than a threshold. During reconstruction of the voice signal, the code is detected in the compressed signal and is replaced with a period of silence of a selected length; decompression is then performed to produce a second voice signal that is expanded with respect to the compressed signal and that is a recognizable reconstruction of the voice signal prior to compression.
Other features and advantages of the invention will become apparent from the following detailed description, and from the claims.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram of a voice compression system that performs multiple stages of compression on a voice signal.
FIG. 2 is a block diagram of a decompression system for reconstructing the voice signal compressed by the system of FIG. 1.
FIG. 3 is a functional block diagram of the first compression stage of FIG. 1.
FIG. 4 shows the processing steps performed by the compression system of FIG. 1.
FIG. 5 shows the processing steps performed by the decompression system of FIG. 2.
FIG. 6 illustrates different modes of operation of the compression system of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, a voice compression system 10 includes multiple compression stages 12, 14 for successively compressing voice signals 15 applied in either live form (i.e., via microphone 16) or as prerecorded speech (such as from a tape recorder or dictating machine 18). The resulting, compressed voice signals can be stored for subsequent use or may be transmitted over a telephone line 20 or other suitable communication link to a decompression system 30. Multiple decompression stages 32, 34 in decompression system 30 successively decompress the compressed voice signal to reconstruct the original voice signal for playback to a listener via a speaker 36.
Compression stages 12, 14 and decompression stages 32, 34 are discussed in detail below. Briefly, assuming a modem throughput of 24,000 bps total with 19,2000 usable bps, the first compression stage 12 implements the LPC-10 procedure discussed above to perform real-time, lossy compression and produce intermediate voice signals 40 that are compressed to a bit rate of about 2400 bps with respect to applied voice signals 15. Second compression stage 14 implements a different type of compression (which in a preferred embodiment is based Lempel-Ziv lossless coding techniques which are described in Ziv, J. and Lempel, A., "A Universal Algorithm for Sequental Data Compression", IEEE Transactions on Information Theory 23(3):337-343, May 1977 (LZ77) and in Ziv, J. and Lempel, A., "Compression of Individual Sequences via Variable-Rate Coding", IEEE Transactions on Information Theory 24(5):530-536, September 1978 (LZ78) the teachings of which are incorporated herein be reference, to additionally compress intermediate signals 40 and produce output signals 42 that are compressed to between 1920 bps and 960 bps from applied voice signals 15.
After transmission over telephone lines 20, first decompression stage 32 applies essentially the inverse of the compression procedure of stage 14 to reconstruct the signal exactly to produce intermediate voice signals 44 that are decompressed with respect to the transmitted compressed voice signals 42. Second decompression stage 34 implements the reverse of the LPC-10 compression procedure to further decompress intermediate voice signals 44 and reconstruct applied voice signals 15 in real-time as output voice signals 46, which are in turn applied to speaker 36.
As discussed above first compression stage 12 preferably performs compression in real time. That is, intermediate signals 40 are produced without any intermediate storage of data substantially as fast as the voice signals 15 are applied, with only a slight delay that inherently accompanies the signal processing of stage 12. Voice compression system 10 is preferably implemented on a personal computer (PC) or workstation, and uses a digital signal processor (DSP) 13 manufactured by Intellibit Corporation to perform the first compression stage 12. A CPU 11 of the PC performs second compression stage 14. Voice signals 15 are applied to DSP 13 in analog form, and are digitized by an analog-to-digital (A/D) converter 48, which resides on DSP 13, prior to undergoing the first stage compression 12. (A preamplifier, not shown, may be used to boost the level of the voice signal produced by microphone 16 or recording device 18.)
The first compression stage 12 produces intermediate compressed voice signals 40 as an uninterrupted series of frames, the structure of which is described below. The frames, which are of fixed length (54 bits), each represent 22.5 milliseconds of applied voice signal 15. The frames that comprise intermediate compressed voice signals 40 are stored in memory 50 as a data file 52. This is done to facilitate subsequent processing of the voice signals, which may not be performed in real time. Because data file 52 is somewhat large (and because multiple data files 52 are typically stored for subsequent additional compression and transmission), the disk storage of the PC is used for memory 50. (Of course, random access memory, if sufficient in size, may be used instead.)
The frames of intermediate signal 40 are produced in real time with respect to analog signal 15. That is, first compression stage 12 generates the frames substantially as fast as analog signal 15 is applied to A/D converter 48. Some of the information in analog signal 15 (or more precisely, in the digitized version of analog signal 15 produced by A/D converter 48) is discarded by first stage 12 during the compression procedure. This is an inherent result of LPC-10 and other real-time speech compression procedures that compress a speech signal so that it can be transmitted over a limited bandwidth channel and is explained below. As a result, analog voice signal 15 cannot be reconstructed exactly from intermediate signal 40. The amount of loss is insufficient, however, to interfere with the intelligibility of the reconstructed voice signal.
A preprocessor 54 implemented by CPU 11 modifies data file 52 in several ways, all of which are discussed in detail below, to prepare data file 54 for efficient compression by second stage 14. The steps taken by preprocessor 54 are discussed in detail below. Briefly, however, preprocessor 54:
(1) "pads" the frame so that each have an integer-byte length (e.g., 56 bits or 7 (8-bit) bytes);
(2) reverses "hashing" of the data in each frame that is an inherent part of the LPC-10 compression process;
(3) removes control information (such as error control and synchronization bits) that are placed in each frame during LPC-10 compression; and
(4) detects frames that correspond to silent portions of voice signal 15 and replaces each such frame with a small (e.g., 1 byte) code that uniquely represents silence.
The modified compressed voice signals 40' produced by preprocessor 54 are stored as a data file 56 in memory 50. It will be appreciated from the above steps that in many cases data file 56 will be smaller in size than, and thus compressed with respect to, data file 52.
Second stage 14 of compression is performed by CPU 11 using by any suitable data compression technique. In the preferred embodiment, the data compression technique uses the LZ78 dictionary encoding algorithm for compressing digital data files. An example of a software product which implements these techniques is PKZIP which is distributed by PKWARE, Inc. of Brown Deer, Wis. The output signal 42 produced by second stage 14 is a highly compressed version of applied voice signal 15. We have found that the successive application of the different types 12, 14 of compression and the intermediate preprocessing 54 cooperate to provide a total compression that exceeds 1920 bps in all cases and in some cases approaches 960 bps. That is, voice signals 15 that are an hour in length (such as would be produced, e.g., by an hour's worth of dictation on a dictation machine or the like) are compressed into a form 42 that can be transmitted over telephone lines 20 in as little as 3 minutes. Moreover, significantly less memory space is needed to store data file 58 than would be required for the digitized voice signal produced by A/D converter 24.
As discussed above, the second compression stage 14 may not operate in real time. If it does not operate in real time, data file 58 is written into memory 50 slower than data file 52 is read from memory 50 by preprocessor 54. Second compression stage 14 does, however, operate losslessly. That is, second stage 14 does not discard any information contained in data file 56 during the compression process. As a result, the information in data file 56 can be, and is, reconstructed exactly by decompression of data file 58.
A modem 60 processes data file 58 and transmits it over telephone lines 20 in the same manner in which modem 60 acts on typical computer data files. In a preferred embodiment, modem 60 is manufactured by Codex Corporation of Canton, Mass. (model no. 3260) and implements the V.42 bis or V.fast standard.
Decompression system 30 is implemented on the same type of PC used for compression system 10. Thus, a modem 64 (also, preferably a Codex 3260) receives the compressed voice signal from telephone line 20 and stores it as a data file 66 in a memory 70 (which is disk storage or RAM, depending upon the storage capacity of the PC). CPU 33 implements decompression techniques to perform first stage decompression 32, which "undoes" the compression introduced by second compression stage 14, and the resulting intermediate voice signal 44 is expanded in time with respect to compressed voice signal 42. In the preferred embodiment, the decompression techniques must be based on the LZ78 dictionary encoding algorithm, and a suitable decompression software package is PKUNZIP which is also distributed by PKWARE, Inc. intermediate voice signal 44 is stored as a data file 72 in memory 70 that is somewhat larger in size than data file 66.
The first decompression stage 32 may not operate in real time. If it does not operate in real time, data file 72 is not written into memory 70 as fast as data file 66 is read from memory 70. First decompression stage 32 does operate losslessly, however. Thus, no information in data file 66 is discarded to create intermediate voice signal 44 and data file 72.
CPU 33 implements preprocessing 74 on data file 72 to essentially reverse the four steps discussed above that are performed by preprocessor 54. Thus, preprocessor 74:
(1) detects the silence-indicating codes in data file 72 and replaces them with frames of predetermined length (7 (8-bit) bytes or 56 bits) that correspond to silent portions of the voice signal 15;
(2) replaces the control information (such as error control and synchronization bits) in each frame for use during LPC-10 decompression;
(3) re-"hashes" the data in each frame so that each frame can be properly decompressed by the LPC-10 process; and
(4) removes the "pad" bits from each to return the frames to the 54 bit length expected by second decompression stage 34.
The resulting data file 76 is stored in memory 70.
Second decompression stage 34 and a digital-to-analog (D/A) converter 78 are implemented on an Intellibit DSP 35. Second decompression stage 34 decompresses data file 76 according to the LPC-10 standard and operates in real time to produce a digitized voice signal 80 that is expanded with respect to intermediate voice signal 44 and data file 76. That is, digitized voice signal 80 is produced substantially as fast as data file 76 is read from memory 70. The reconstructed voice signal 46 is produced by D/A converter 78 based on digitized voice signal 80. (An amplifier which is typically used to boost analog voice signal 46 is not shown.)
Referring to FIG. 3, first compression stage 12 is shown in block diagram form. A/D converter 48 (also shown in FIG. 1) performs pulse code modulation on analog voice signal 15 (after the speech has been filtered by bandpass filter 100 to remove noise) to produce a digitized voice signal 102 that has a bit rate of 128,000 bits per second (b/s). Although digitized voice signal 102 is a continuous digital bit stream, first compression stage 12 analyzes digitized voice signal 102 in fixed length segments that can be thought of as input frames. Each input frame represents 22.5 milliseconds of digitized voice signal 102. There are no boundaries or gaps between the input frames. As discussed below, first compression stage 12 produces intermediate compressed signal 40 as a continuous series of 54 bit output frames that have a bit rate of 2400 bps.
Pitch and voicing analysis 104 is performed on each input frame of digitized voice signal 102 to determine whether the sounds in the portion of analog voice signal 15 that correspond to that frame are "voiced" or "unvoiced." The primary difference between these types of sounds is that voiced sounds (which emanate from the vocal chords and other regions of the human vocal track) have pitch, while unvoiced sounds (which are sounds of turbulence produced by jets of air made by the mouth during elocution) do not. Examples of voiced sounds include the sounds made by pronouncing vowels; unvoiced sounds are typically (but not always) associated with consonant sounds (such as the pronunciation of the letter "t").
Pitch and voicing analysis 104 generates, for each input frame, a one byte (8 bit) word 106 which indicates whether the frame is voiced 106a and the pitch 106b of voiced frames. The voicing indication 106a is a single bit of word 106, and is set to a logic "1" if the frame is voiced. The remaining seven bits 106b are encoded according to the LPC-10 standard into one of sixty possible pitch values that corresponds to the pitch frequency (between 51 Hz and 400 Hz) of the voiced frame. If the frame is unvoiced, by definition it has no pitch, and all bits 106a, 106b are assigned a value of logic "0."
Pre-emphasis 108 is performed on digitized voice signal 102 to provide immunity to noise by preventing spectral modification of the signal 102. The RMS (root mean square) amplitude 114 of the preemphasized voice signal 112 is also determined. LPC (linear predictive coding) analysis 110 is performed on the preemphasized digitized voice signal 112 to determine up to ten reflection coefficients (RCs) possessed by the portion of analog voice signal 15 corresponding to the input frame. Each RC represents a resonance frequency of the voice signal. According to the LPC-10 standard, the full complement of ten reflection coefficients (RC(1)-RC(10)! are produced for voiced frames; unvoiced frames (which have fewer resonances) cause only four reflection coefficients (RC(1)-RC(4)! to be generated.
Pitch and voicing word 106, RMS amplitude 114, and reflection coefficients 116 are applied to a parameter encoder 120, which codes this information into data for the 54 bit output frame. The number of bits assigned to each parameter is shown in Table I below:
______________________________________ Voiced Nonvoiced______________________________________Pitch & Voicing 7 7RMS Amplitude 5 5RC(1) 5 5RC(2) 5 5RC(3) 5 5RC(4) 5 5RC(5) 4RC(6) 4RC(7) 4RC(8) 4RC(9) 3RC(10) 2Error Control 20Synchronization 1 1Unused 1Total 54 54______________________________________
As can readily be appreciated, some parameters (such as pitch and voicing, RMS amplitude, and reflection coefficients 1-4) are included in every output frame, voiced or unvoiced. Unvoiced frames are not allocated bits for reflection coefficients 5-10. Note that 20 bits are set aside in unvoiced frames for error control information, which is inserted downstream, as discussed below, and one bit is unused in each unvoiced output frame. That is, approximately 40% of the length of every unvoiced frame contains error control information, rather than data that describes voice sounds. Both voiced and unvoiced output frames contain one bit for synchronization information (described below).
The 20 bits of error control information are added to unvoiced frames by an error control encoder 122. The error control bits are generated from the four most significant bits of the RMS amplitude code and reflection coefficients RC(1)-RC(4), according to the LPC-10 standard.
Finally, the output frame is passed to framing and synchronization function 124. Synchronization between output frames is maintained by toggling the single synchronization bit allocated to each frame between logic "0" and logic "1" for successive frames. To guard against loss of voice information in case one or more bits of the output frame are lost during transmission, framing and synchronization function 124 "hashes" the bits of the pitch and voicing, RMS amplitude, and RC codes within each output frame as shown in Table II below:
__________________________________________________________________________Bit Voiced Nonvoiced Bit Voiced Nonvoiced Bit Voiced Nonvoiced__________________________________________________________________________1 RC(1)-0 RC(1)-0 19 RC(3)-3 RC(3)-3 37 RC(8)-1 R-6*2 RC(2)-0 RC(2)-0 20 RC(4)-2 RC(4)-2 38 RC(5)-1 RC(1)-6*3 RC(3)-0 RC(3)-0 21 R-3 R-3 39 RC(6)-l RC(2)-6*4 P-0 P-0 22 RC(1)-4 RC(1)-4 40 RC(7)-2 RC(3)-7*5 R-0 R-0 23 RC(2)-3 RC(2)-3 41 RC(9)-0 RC(4)-6*6 RC(1)-1 RC(1)-1 24 RC(3)-4 RC(3)-4 42 P-5 P-57 RC(2)-1 RC(2)-1 25 RC(4)-3 RC(4)-3 43 RC(5)-2 RC(1)-7*8 RC(3)-1 RC(3)-1 26 R-4 R-4 44 RC(6)-2 RC(2)-7*9 P-1 P-1 27 P-3 P-3 45 RC(10)-1 Unused10 R-1 R-1 28 RC(2)-4 RC(2)-4 46 RC(8)-2 R-7*11 RC(1)-2 RC(1)-2 29 RC(7)-0 RC(3)-5* 47 P-6 P-612 RC(4)-0 RC(4)-0 30 RC(8)-0 R-5* 48 RC(9)-1 RC(4)-7*13 RC(3)-2 RC(3)-2 31 P-4 P-4 49 RC(5)-3 RC(1)-8*14 R-2 R-2 32 RC(4)-4 RC(4)-4 50 RC(6)-3 RC(2)-8*15 P-2 P-2 33 RC(5)-0 RC(1)-5* 51 RC(7)-3 RC(3)-8*16 RC(4)-1 RC(4)-1 34 RC(6)-0 RC(2)-5* 52 RC(9)-2 RC(4)-8*17 RC(1)-3 RC(1)-3 35 RC(7)-1 RC(3)-6* 53 RC(8)-3 R-8*18 RC(2)-2 RC(2)-2 36 RC(10)-0 RC(4)-5* 54 Synch. Synch.__________________________________________________________________________
In the above table:
P=pitch
R=RMS amplitude
RC=reflection coefficient
In each code, bit 0 is the least significant bit. (For example, RC(1)-0 is the least significant bit of reflection code 1.) An asterisk (*) in a given bit position of an unvoiced frame indicates that the bit is an error control bit.
Intermediate compressed voice signal 40 produced by framing and synchronization function 124 thus is a continuous series of 54 bit frames each of which contains hashed data describing parameters (e.g., amplitude, pitch, voicing, and resonance) of the portion of applied voice signal 15 to which the frame corresponds. The frames also include a degree of control information (synchronization alone for voiced frames, and, additionally, error control information for unvoiced frames). The frames of intermediate compressed voice signal 40 are produced in real time with respect to applied voice signal and, as discussed, are stored as a data file 52 in memory 50 (FIG. 1).
FIG. 4 is a flow chart showing the operation (130) of compression system 10. The first two steps, performing the first stage 12 of compression (132) and storing the intermediate compressed voice signal 40 in data file 52 (134) were described above. The next four steps are performed by preprocessor 54.
As discussed above, the frames produced by first compression stage 12 are 54 bits long, and thus have non-integer byte lengths. Data compression procedures, such as PKZIP performed by second compression stage 14 compress data based on redundancies that occur in the data stream. Thus, these procedures work most efficiently on data that have integer byte lengths. The first step (136) performed by preprocessor 54 is to "pad" each frame with two logic "0" bits (logic "1" values could be used instead) to cause each frame to have an integer (7) byte length of exactly 56 bits.
Next, preprocessor "dehashes" each frame (138). The hashing performed during first compression stage 12 inherently masks redundancies that occur from frame-to-frame in the various parameters of the voice information. The dehashing performed by preprocessor 54 rearranges the data in each frame so that the data for each voice parameter appears together in the frame. As rearranged, the data in each frame appears as shown in Table I above, with the exception that the 5 RMS amplitude bits appear first in the dehashed frame, followed by the pitch and voicing bits; the remainder of the frame appears in the order shown in Table I (the two pad bits occupy the least significant bits of the frame).
The error control bits, the synchronization bit, and of course the unused and pad bits of unvoiced frames contain no information about the parameters of the voice signal (and, as discussed above, the error control bits are formed from the RMS amplitude information and the first four reflection coefficients, and can thus be reconstructed at any time from this data). Thus, the next step performed by preprocessor 54 is to "prune" these bits from unvoiced frames (140). That is, the 20 error control bits, the synchronization bit, and the two pad bits are removed from each unvoiced frame (as discussed above, the one byte pitch and voicing data 106 in each frame indicates whether the frame is voiced or not). As a result, unvoiced frames are reduced in size (compressed) to 32 bits (4 bytes). Note that the integer byte length is maintained. Pruning (140) is not performed on voiced frames, because the reduction in frame size (by three bits) that would be obtained is relatively small and would result in voiced frames having non-integer byte lengths.
The final step performed by preprocessor 54 is silence gating (142). Each silent frame (be it a voiced frame or an unvoiced frame) is replaced in its entirety with a one byte (8 bit) code that uniquely identifies the frame as a silent frame. Applicant has found that 10000000 (80 HEX ) is distinct from all codes used by LPC-10 for RMS amplitude (which all have a most significant bit=0), and thus is a suitable choice for the silence code. LPC-10 does not distinguish between silent and nonsilent frames--voicing data and reflection coefficients are produced for silent frames even though this information is not heard in the reconstructed analog voice signal. Thus, replacing silent frames with a small code dramatically decreases the amount of data that need be transmitted to decompression system 30 without loss of any meaningful voice information. Silence is detected based on the 5 bit RMS amplitude code of the frame. Frames whose RMS amplitude codes are 0 (i.e., 00000) are deemed to be silent. (Of course, another suitable code value may instead be used as the silence threshold, if desired.)
To summarize, the preprocessor 54 reduces the size of nonsilent, unvoiced frames from 54 bits to 32 bits (4 bytes), and replaces each 54 bit silent frame with an 8 bit (1 byte) code. Voiced frames that are not silent are slightly increased in size, to 56 bits (7 bytes). Preprocessor 54 stores the frames of modified, compressed voice signal 40' are stored (144) in data file 56 (FIG. 1).
Second stage 14 of compression is then performed on data file 56 to compress it further according to the dictionary encoding procedure implemented by PKZIP or any other suitable compression technique (146). Second compression stage 14 compresses data file 56 as it would any computer data file--the fact that data file 56 represents speech does not alter the compression procedure. Note, however, that steps 136-142 performed by preprocessor greatly increase the speed and efficiency with which second compression stage 14 operates. Applying integer-length frames to second compression stage 14 facilitates detecting regularities and redundancies that occur from frame to frame. Moreover, the decreased sizes of unvoiced and silent frames reduces the amount of data applied to, and thus the amount of compression needed to be performed by, second stage 14.
Output 42 of second compression stage 14 is stored in data file 58 (148) that is compressed to between 50% and 80% of the size of data file 56. Depending on such factors as the amount of silence in the applied voice signal 15 and the continuity and redundancy of the voice signal, the digitized voice signal represented by output 42 is compressed to between 1920 bps and 960 bps with respect to the applied voice signal 15.
CPU 11 then implements a telecommunications procedure (such as Z-modem) to transmit data file 58 over telephone lines 20 (150). CPU 11 also invokes a dialer (not shown) to call the receiving decompression system 30 (FIG. 1). When the connection with decompression system 30 has been established, the Z-modem procedure invokes the flow control and error detection and correction procedures that are normally performed when transmitting digital data over telephone lines, and passes data file 58 to modem 60 as a serial bit stream via an RS-232 port of CPU 11. Modem 60 transmits data file 60 over telephone line 20 at 24000 bps according to the V.42 bis protocol.
FIG. 5 shows the processing steps (160) performed by decompression system 30. Modem 64 receives (162) the compressed voice signal from a telephone line, processes it according to the V.42 bis protocol, and passes the compressed voice signal to CPU 33 via an RS-232 port. CPU 33 implements a telecommunications package (such as Z-modem) to convert the serial bit stream from modem 64 into one byte (8 bit) words, performs standard error detection and correction and flow control, and stores the compressed voice signal as a data file 66 in memory 70 (164).
First stage 32 of decompression is then performed on data file 66 (166), and the resulting, time-expanded intermediate voice signal 44 is stored as a data file 72 in memory 70 (168). First decompression stage 32 is performed by CPU 33 using a lossless data decompression procedure (such as PKZIP). Other types of decompression techniques may be used instead, but note that the goal of first decompression stage 32 is to losslessly reverse the compression performed by second compression stage 14. The decompression results in data file 72 being expanded by 50% to 80% with respect to the size of data file 66.
The decompression performed by first stage 34 is, like the compression imposed by second compression stage 14, lossless. As a result, assuming that any errors that occur during transmission are corrected by modems 60, 64, data file 72 will be identical to data file 56 (FIG. 1). In addition, data file 72 consists of frames having nonhashed data with three possible configurations: (1) 7 byte, nonsilent voiced frames; (2) 4 byte, nonsilent unvoiced frames; and (3) 1 byte silence codes. Preprocessor 74 essentially "undoes" the preprocessing performed by preprocessor 54 (see FIG. 3) to provide second decompression stage 34 with frames having a uniform size (54 bits) and a format (i.e., hashed) that stage 34 expects.
First, preprocessor 74 detects each 1-byte silence code (80 HEX ) in data file 72 and replaces it with a 54 bit frame that has a five bit RMS amplitude code of 00000 (170). The values of the remaining 49 bits of the frame are irrelevant, because the frame represents a period of silence in applied voice signal 15. The preprocessor 74 assigns these bits logic 0 values.
Next, preprocessor 74 recalculates the 20 bit error code for each unvoiced frame (recall that the value of the pitch and voicing word 106 in each frame indicates whether the frame is voiced or not) and adds it to the frame (172). As discussed above, according to the LPC-10 standard, the value of the error code is calculated based on the four most significant bits of the RMS amplitude code and the first four reflection coefficients (RC(1)-RC(4)!. In addition, preprocessor 74 re-inserts the unused bit (see Table I) into each unvoiced frame. A single synchronization bit is also added to every voiced and unvoiced frame; the preprocessor alternates the value assigned to the synchronization bit between logic 0 and logic 1 for successive frames.
Preprocessor 74 then hashes the data in each frame in the manner discussed above and shown in Table II (174). Finally, preprocessor 74 strips the two pad bits from the frames (176), thereby returning each voiced and unvoiced frame to their original 54 bit length. The frames as modified by preprocessor 74 are stored in data file 76 (178). Neglecting the effects of transmission errors, the nonsilent voiced and unvoiced frames as modified by preprocessor 74 are identical to data file 76 and are identical to the frames as produced by first compression stage 12. (Although the pitch and voicing data (if any) and RC data possessed by the silent frames produced by first compression stage 12 are missing from the silent frames reconstructed by preprocessor 74, this information is not lost as a practical matter, because he portion of applied voice signal that this information represents is silent and thus is not heard when the applied voice signal is reconstructed.)
DSP 35 retrieves data file 76 and performs the second stage 34 of decompression on the data in real time to complete the decompression of the voice signal (180). D/A conversion is applied to the expanded, digitized voice signal 80, and the reconstructed analog voice signal 46 obtained thereby is played back for the user (182). The second decompression stage 34 is preferably implemented using the LPC-10 protocol discussed above, and essentially "undoes" the compression performed by first compression stage 12. Thus, details of the decompression will not be discussed. A functional block diagram of a typical LPC-10 decompression technique is shown in the federal standard discussed above.
Referring also to FIG. 6, the operation of compression system 10 is controlled via a user interface 62 to CPU 11 that includes a keyboard (or other input device, such as a mouse) and a display (not separately shown). System 10 has three basic modes of operation, which are displayed to the user in menu form 190 for selection via the keyboard. When the user chooses the "input" mode (menu selection 192), CPU 11 enables the DSP 13 to receive applied voice signals 15 as a "message," perform the first stage of compression 12, and store intermediate signals 40 that represent the message in data file 52. Preprocessing 54 and second stage of compression 14 are not performed at this time. The user is prompted to identify the message with a message name, CPU 11 links the name to the stored message for subsequent retrieval, as described below. Any number of messages (limited, of course, by available memory space) can be applied, compressed, and stored in memory 50 in this way.
The user can listen to the stored voice signals for verification at any time by selecting the "playback" mode (menu selection 194) and entering the name of the message to be played back. CPU 11 responds by retrieving the message from data file 52, and causing DSP 13 to decompress it according to the LPC-10 standard (i.e., using the same decompression procedure as that performed by decompression stage 34), reconstruct the spoken message by D/A conversion, and apply the message to a speaker. (The playback circuitry and speaker are not shown in FIG. 1.) The user can record over the message if desired, or may maintain the message as is in memory 50.
The user commands compression system 10 to transmit a stored message to decompression system 30 by entering the "transmit" mode (menu selection 196) and selecting the message (e.g., using the keyboard). The user also identifies the decompression system 30 that is to receive the compressed message (e.g., by typing in the telephone number of system 30 or by selecting system 30 from a displayed menu). CPU 11 retrieves the selected message from data file 52, applies preprocessing 54 and performs second stage 14 of decompression to fully compress the message, all in the manner described above. CPU 11 then initiates the call to decompression system 30 and invokes the telecommunications procedures discussed above to place the fully compressed message on telephone lines 20.
The operation of decompression system 30 is controlled via user interface 73, which provides the user with a menu (not shown) of operating modes. For example, the user may select any of the messages stored in data file 66 for listening. CPU 33 and DSP 35 respond by decompressing and reconstructing the selected message in the manner discussed above.
For maximum flexibility, each system 10, 30 may be configured to perform both the compression procedures and the decompression procedures described above. This enables users of systems 10, 30 to exchange highly compressed messages using the techniques of the invention.
Other embodiments are within the scope of the following claims.
For example, techniques other than LPC-10 may be used to perform the real-time, lossy type of compression. Alternatives include CELP (code excited linear prediction), SCT (sinusoidal transform coding), and multiband excitation (MBE). Moreover, alternative lossless compression techniques may be employed instead of PKZIP (e.g., Compress distributed by Unix Systems Laboratories. Also, while the detection of portions of the speech signal representing silence are described above, other repeated patterns could also be removed or removed instead of the silent portions.
Wireless communication links (such as radio transmission) may be used to transmit the compressed messages.
While the foregoing invention has been described with reference to its preferred embodiments, various alterations and modifications will occur to those skilled in the act. For example, the compression ratios described in this application will change if the modem throughout is changed. In addition, while the term "bps" might imply a fixed bit rate, it should be understood that since the invention described herein allows variable bit rates, the bit rates expressed above are "average" bit rates. All such alterations and modifications are intended to fall within the scope of the appended claims. | Voice compression is performed in multiple stages to increase the overall compression between the incoming analog voice signal and the resulting digitized voice signal over that which would be obtained if only a single stage of compression were to be used. A first type of compression is performed on a voice signal to produce an intermediate signal that is compressed with respect to the voice signal, and a second, different type of compression is performed on the intermediate signal to produce an output signal that is compressed still further. As a result, compression better than 1920 bits per second (and approaching 960 bits per second) are obtained without sacrificing the intelligibility of the subsequently reconstructed analog voice signal. Voice compression is also performed by recognizing redundant portions of said voice signal, such as silence, and replacing such redundant portions with a special code in said compressed signal. Among other advantages, the higher total compression allows speech to be transmitted in far less time than would otherwise be possible, thereby reducing expense. | 6 |
This is a division of Ser. No. 800,038, filed Nov. 20, 1985, now U.S. Pat. No. 4,830,808.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the manufacture of tubular fibrous products or shells, intended particularly for the heat insulation of conduits and made of mineral fibers, for example of glass, agglomerated by a polymerized binder. The invention relates more particularly to techniques for winding of felts of mineral fibers around a mandrel of a predetermined length to produce cylindrical shells.
2. Discussion of the Art
According to these techniques, a felt of mineral fibers impregnated with a binder consisting of a polymerizable resin, for example of the melanin formaldehyde, phenyl-formaldehyde or phenol-urea type, is cut into sections of a predetermined length. Each section of felt is wound around a revolving mandrel while the polymerization of the binder begins, which is then completed in a heated chamber.
This process is particularly known from U.S. Pat. No. 4,153,498 to which special reference is made. In this process the revolving mandrel, around which the felt of mineral fibers is wound, is heated. This heating of the mandrel facilitates the anchoring of the first layer or wrap of felt. The temperature is selected so that an inner surface of the shell hardened by the polymerization of the binder in the vicinity of the mandrel is formed during the winding time. Thus, as soon as the winding ends, the shell can be separated from its mandrel and can be transferred to a device which assures the smoothing and hardening of the outside surface of the shell. At this stage, it exhibits hardened inner and outer surfaces while apart from these inner and outer surfaces, the polymerization of the binder remains incomplete. Polymerization is then completed homogeneously through the entire thickness of the shell in a heated chamber.
Also according to French Pat. No. 4,153,498, the winding of the felt around the revolving mandrel is performed while maintaining the speed of the mandrel, leading to an accelerated tangential speed. Because of this, the thickness of the shell being formed increases with a constant speed.
This process is perfectly suited for the production of shells of small inside and outside diameters, for which only small lengths of felt of mineral fibers need be wound, for example less than 6 meters. Feeding the winding device should be performed at an accelerated speed, however it is impossible to increase the speed for feeding felt of mineral fibers too much without risking a tearing of the felt which is made more fragile by the fact that the mineral fibers are not yet bound to one another. The maximum feeding speed reached at the end of winding is a function of the outside diameter of the shell and of the rotation speed of the mandrel, and should be less than the speed beyond which the felt might be torn. This calls for a maximum rotation speed of the mandrel, to be inversely proportional to the outside diameter of the shaped shell at the end of winding. This limitation becomes particularly constraining for shells of large outside diameter. Thus, by way of example, if a feeding speed limited to 50 meters per minute is assumed, for a shell with an outside diameter of 400 mm, the mandrel should have a constant rotation speed less than 40 revolutions per minute. With layers of an average thickness of about 0.3 mm, a winding time for a shell of 100 mm total thickness is greater than 8 minutes. The rate of production according to this example would therefore be very low.
According to another important characteristic of U.S. Pat. No. 4,153,498, during the entire time of winding, pressing elements remain in contact with the shell being formed. These pressing elements consist, for example, of three counterrollers placed around the heated revolving mandrel. Simultaneously withdrawing from the axis of the mandrel as the shell is formed, these counterrollers assure, on the one hand, the uniformity of the winding and, on the other hand, the cohesion of the shell. Actually, these counterrollers define uniform lines of contact with the shell being formed, which define the general shape of the shell during the winding time. In addition, by the way their pressure is exerted, the counterrollers avoid any non-uniformity of the layers of wound felt.
In practice, three counterrollers are satisfactory for "small" shells, i.e., shells whose inside diameter is between 12 and 100 mm and whose outside diameter is less than 200 mm. When these limiting values are exceeded, for example for shells whose outside diameter reaches 500 mm, three contact points prove insufficient to define the shape of the shell correctly and the counterrollers no longer assure the desired cohesion. Since the squeezing of the shell is maintained by the counterrollers, the pressure exerted is all the greater if a large portion of the outside surface of the shell is in contact with the counterrollers; in other words, if the surface of each counterroller in contact with the shell is increased. However, this contact surface is limited by the fact that the diameter of the counterrollers cannot exceed such a value that the counterrollers are both tangential to one another and to the heated revolving mandrel which determines the value of the inside diameter of the shell. Of course, it would be possible to increase the number of counterrollers, but their diameter would then have to be reduced for the same reasons of bulk. Because of this, an installation well-suited to the production of shells of small inside diameter would provide shells of average inside diameter and/or of average thickness of poor quality while, reciprocally an installation well suited to the production of shells of average inside diameter would not be able to produce shells of small inside diameter, because no pressure would then be exerted on the first wound layers.
The use of this process of the art for the production of shells of average thickness also runs into an additional difficulty connected with the compressibility of the product. Actually, according to this process, the counterrollers are gradually withdrawn from the axis of the revolving mandrel so that during the entire winding phase, a constant force is exerted on the felt of mineral fibers by the counterrollers. Consequently, the first layers or wraps wound, whose outer surface remains not far from the completely rigid surface of the revolving mandrel, are more compressed than the last wraps which are separated from the rigid mandrel by considerable thickness of compressible felt. Because of the partial elasticity of the felt of mineral fibers, and because of this difference in compression, the pickup of thickness of the shell is greater at the end of winding; the result is a shaped shell whose outside diameter is imperfectly controlled and greater than the expected theoretical diameter.
SUMMARY OF THE INVENTION
This invention has as its object to improve the prior techniques for producing shells by winding a felt of mineral fibers impregnated with a binder around a revolving mandrel. In particular, the invention has as its object a process and an installation for manufacturing insulating shells whose inside diameter and thickness can vary within relatively wide limits.
According to the invention, there are continuously manufactured insulating shells made of mineral fibers agglomerated by a binder while winding a felt, impregnated with a binder in the nonpolymerized state, around a heated revolving mandrel whose temperature is such that an inner hardened surface is formed on contact during winding and while exerting a certain pressure on the shell being formed, on the one hand, by pressing elements consisting of main counterrollers which remain in contact with the outer surface of the shell during the entire winding phase and, on the other hand, by auxiliary pressing elements which come in contact with the shell only when the outside diameter of the shell reaches a given value during shaping.
Depending on whether the diameter of the mandrel is or is not greater than this value in question, the auxiliary counterrollers do or do not intervene as soon as winding begins. The choice of the dimension for which the auxiliary counterrollers intervene is a function of the maximum values of the inner and outer dimensions of the shells able to be shaped with the winding device. In any case, this choice is always the result of a compromise, the maximum effectiveness of the counterrollers being obtained at the beginning of their intervention.
For example, to produce insulating shells whose inside diameter, depending on needs, can vary between 12 and 400 mm and whose outside diameter reaches up to 500 mm, three main counterrollers are advantageously used which alone intervene as long as the outside diameter of the shell remains, for example, less than 200 mm, and three auxiliary counterrollers which additionally intervene as soon as the outside diameter of the shell reaches this 200 mm value, either because of the wound felt thickness or simply because the selected revolving mandrel itself has a diameter greater than or equal to 200 mm. The auxiliary counterrollers are placed in contact with the felt and controlled so that they withdraw from the axis of the heated revolving mandrel with the same instantaneous speed as that of the main counterrollers, thus exerting an identical pressure on the wound felt.
Preferably, according to the invention, the pressure exerted by the main, and possibly auxiliary, counterrollers is increased as the winding progresses by reducing the withdrawal speed, which makes it possible to obtain an approximately identical compression for all the wound felt wraps.
According to a preferred characteristic of the invention, the reduction of the withdrawal speed of the counterrollers is performed with a constant deceleration; the withdrawal speed at the end of winding being selected equal to the speed of increase of the diameter of a perfect shell, this theoretical speed being calculated for a diameter value equal to the outside diameter of the shaped shell obtained by the winding of a strip of incompressible material.
Also preferably, the felt of mineral fibers is wound at an approximately constant tangential speed which implies that the rotation speed of the mandrel, at any time, is a function of the outside diameter of the shell being formed. According to a particularly simple embodiment the rotation speed of the mandrel is reduced in a linear manner, the rotation speeds at the beginning and end of winding calculated on the assumption of a winding at constant tangential speed being taken as a reference.
It should be noted that a linear reduction of the speed of the revolving mandrel has the effect of bringing about a slight stretching of the wound felt which is thus compressed around the mandrel. This leads to a greater density for the shaped shell. On the one hand, this increase in the density of the product reduces the bulk of the product which facilitates its being placed around conduits; on the other hand, the shells made of glass fibers for thermal insulation generally have a density close to 60 kg/m 3 . The coefficient of thermal conductivity can be expressed as a function of the density of the product in the following manner λ=A +B . ρ+C/ρ, where A, B and C are variables that essentially depend on the temperature and the nature of the product. In the case of glass fibers, the thermal conductivity remains minimum for a density around 60-90 kg/m 3 . Therefore, a slight variation of the density here does not have a serious effect on the coefficient of thermal conductivity, i.e., on the insulating capability of the shaped shell.
The invention also has as its object a device for winding a felt of mineral fibers around a heated revolving mandrel that can produce shells whose inside and outside diameters can vary within wide limits while exhibiting a good uniformity of shape. Thus, according to an embodiment of the invention, the inside diameter varies between 12 and 400 mm, while the outside diameter remains less than 500 mm.
The device according to the invention essentially comprises a frame which, on the one hand, supports a revolving mandrel made of two half-mandrels driven together in rotation and equipped with electrical resistors that provide heating and, on the other hand, main counterrollers and auxiliary counterrollers each equipped with a device for driving the same in rotation and with a device that assures moving these counterrollers away or closer in relation to the axis of the revolving mandrel. In addition, a device makes it possible to retract the auxiliary counterrollers.
The winding device according to the invention makes possible automation and requires only a minimum of operations for the exchange from one given type of shells for another.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views and wherein:
FIG. 1 is a schematic view of a device for manufacturing insulating shells comprising a winding device according to the invention,
FIG. 2 is a schematic view of a winding device according to the invention in ejection position,
FIG. 3 is a schematic view of the winding device of FIG. 2 with the main counterrollers used while the auxiliary counterrollers are in a retracted position,
FIG. 4 is a schematic view of the winding device of FIG. 2 with the main and auxiliary counterrollers used,
FIG. 5a is a graph of the variation, during winding, of the outside diameter of the shell, during formation, for 3 types A, B and C of insulating shells,
FIG. 5b is a graph of the variation, during winding, of the instantaneous speed curve of the heated revolving mandrel, corresponding to shells A, B and C; and
FIG. 6 is a graph of the variation, during winding, of the instantaneous withdrawal speed of the counterrollers, for shells A, B and C.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 are represented the main elements constituting a device for forming insulating shells made of mineral fibers, particularly of glass, held by a binder. Each shell is formed from a section 1 of felt of mineral fibers, particularly of glass, in which a binder is dispersed in the nonpolymerized state. The section is obtained, for example, by a tearing of the felt caused by a sudden pull on it. Section 1 is brought by a feeding conveyor 2 to a winding device 3. To avoid any deterioration of the still very fragile felt, since the fibers are not fixed to one another by the polymerized binder, feeding conveyor 2 preferably has a polyvinyl chloride belt. In addition, according to a preferred embodiment of the invention, the feeding speed is selected to be constant; in this way any slipping of the sections against the conveyor which can cause losses of fibers are avoided. Moreover, this feeding speed can be selected relatively close to the production speed of the felt of mineral fibers.
Winding device 3 has a revolving mandrel 4 and counterrollers 5 which withdraw from the axis of the mandrel as felt 1 is wound. These counterrollers 5 exert a pressure on the shell being formed. Thus, they assure a good cohesion of the shell while inhibiting the formation of folds.
The revolving mandrel is heated to such a temperature that the inner surface of the shell is hardened by the polymerization of the binder in the vicinity of the mandrel. By way of example, for ordinary binders with a base of formaldehydephenolic resins, the mandrel may be heated to a constant temperature in the order of 350°-400° C., regardless of the thickness of the shaped shell. This makes it possible to obtain a polymerized thickness which is larger with a greater thickness of the shaped shell. Thus, independently of its size, the shell exhibits a certain rigidity which facilitates its ejection from the mandrel. As soon as the winding ends, shaped shell 6 is separated from mandrel 4 and transferred by device 7 with pivoting arms to smoothing device 8 which makes possible the formation of a "skin" on the outside surface of shell 6'. Smoothing device 8 comprises a hinged conveyor 9 and a smoothing plate 10 that can be raised or lowered to suit various outer diameters of shells, and is equipped with electrical resistors. Its temperature is regulated at about 400° C., for the type of binders considered by way of example.
Shell 6' is driven in rotation by contact with an upper portion of its generatrix on smooth plate 10 and with a lower portion of its generatrix on conveyor 9. In addition to the formation of a "skin", this smoothing device 8 also allows a possible surface treatment of the shaped shell.
After smoothing, the shell which has inner and outer hardened surfaces, while the binder has not yet completely polymerized between these peripheral surfaces, is brought to a polymerization oven 11 via a receiving table 12. For details of this polymerization oven, reference is made to French Pat. No. 2,325,007 and 2,548,586, the latter describing a microwave oven whose use is preferred here.
The polymerized shells are then brought to a cooling device, then placed lengthwise and finally cut lengthwise to make it possible to position them around conduits.
FIG. 2 shows, in greater detail, an embodiment of a winding device according to the invention. It includes a mechanically welded frame 13 which supports the various parts of the winder and their movement device.
Revolving mandrel 14 is composed of two axially spaced cylindrical half-mandrels, not separately shown, made for example of stainless steel, rotated together by a motor, preferably a direct current motor, or each independently driven in rotation, the two motors then being connected by a device for synchronization in relation to one another.
These two half-mandrels can be separated from one another to permit the ejection of a shaped shell. To do this, they are each equipped with a device for driving the same in translation along its axis, this device consisting of a hydraulic jack which controls the movement of the support of a half-mandrel and its motor.
Heating of the mandrel is provided by a bundle of electrical resistors distributed inside the mandrel and spaced as a function of its diameter.
While the felt is wound around the mandrel, counterrollers 15, 15', 15", 16, 16' and 16", exert a slight pressure on the outer surface of the shell. As FIGS. 2 and 3 in particular show, rotationally driven counterroller 15 is mounted on an axis fixed on a support plate 17, itself hinged for rotation around axis 18 which is connected to a stationary plate 19. Counterroller 15 can therefore describe the path of circle 20 passing through the axis of symmetry of the mandrel. This movement of support plate 17 is controlled by a rotary hydraulic jack 21. To do this, a point A of plate 17 is connected by a connecting rod 22 to an end D of a shaft 23 rotatable around fixed axis E. This rotation of shaft 23 is itself transmitted by shaft 24, rotatable around axis E and fixed to shaft 23 End F of shaft 24 is moved by the forward or backward movement of hinged jack 21, rotatable around fixed axis G, so that a movement of rod 25 brings about a movement of counterroller 15. The length of rod 25 is such that at the end of its travel, counterroller 15, placed at C, is in contact with the smallest mandrel that can be used. In practice, the mandrels used do not have a diameter less than 12 mm.
For greater clarity, so far we have mentioned only the case of the first counterroller 15. Counterrollers 15' and 15" are mounted in the same way on a support plates 17' and 17", hinged around axes 18' and 18" which are supported by frames 19' and 19". Plates 17' and 17" are controlled to move together with plate 17 by hinged arms 26' and 26'.
In FIGS. 2, 3 and 4, each auxiliary counterroller 16, 16' and 16" is rotatably mounted and driven on an arm 27, 27' and 27" rotatable about a stationary axis H connected to one of the plates 19, 19' or 19". The rotation of each arm about axis H is controlled by a hydraulic jack 28, 28' or 28" mounted to support plate 17, 17' or 17" and which, through its arm 29, transmits to arm 27 the rotation movement of support plate 17, 17' or 17". It should be noted that hydraulic jack 28 must be sized and positioned such that when its piston rod is deployed, the generatrix of the auxiliary counterrollers 16, 16' or 16" closest to the axis of the mandrel is located on a cylinder 31 that also is tangent to the generatrices of primary counterrollers 15, 15' or 15", this cylinder 31 representing the outside envelope of the shell being formed, and shown more particularly in FIG. 4.
At the end of the counterrollers are placed flanges (not shown), mounted on a pivot and fixed to the rotary movements of support plates 17, 17' and 17". These flanges carry jacks identical with jacks 28, 28' and 28" and work in perfect synchronization with them, which makes it possible to retract auxiliary counterrollers 16, 16' and 16". These flanges also support hydraulic motors that drive the counterrollers in rotation.
The operation of the winder according to the invention is as follows. Initially, the main counterrollers 15 are brought together so that the central space left free between them is just enough to allow the passage of the two half-mandrels. The main counterrollers thus assure a guiding function for the half-mandrels, particularly important in the case of shell of small inside diameter, because a significant sagging effect otherwise occurs, since the half-mandrels are held only by one of their ends. It is noted that the diameter of the half-mandrels will preferably be 0.5 mm less than the inside diameter of the shaped shell. Thus, as soon as the first wrap of felt of mineral fibers is wound around the mandrel, counterrollers 15, 15' and 15" are in contact with the shell being formed. As the felt is wound, the outside diameter of the shell grows and counterrollers 15, 15' and 15" move away from the axis of the mandrel, their movement being controlled by the gradual backward movement of rod 25 of jack 21. When the outside diameter of the shell reaches, for example 200 mm, the auxiliary counterrollers --until then retracted --come into a work position, i.e., the piston rods of jacks 28, 28' and 28" are fully deployed (FIG. 4), which brings auxiliary counterrollers 16, 16' and 16" in contact with the shell. The movements of counterrollers 16, 16' and 16" are then controlled by those of support plates 17, 17' and 17" so that they exert a pressure identical with that of main counterrollers 15, 15' and 15".
Preferably, and as shown in FIGS. 2 to 4, auxiliary counterrollers 16, 16' and 16" have a diameter greater than that of the main counterrollers. Actually, to assure a compression distributed as well as possible over the outside surface of the shell, it is important to have a large contact surface. Now, it is clear that to be able to draw in the main counterrollers as soon as the winding phase
begins, it is not possible to have main counterrollers with a diameter greater than ##EQU1## where d m is the diameter of the mandrel.
In a multipurpose installation as preferably envisaged according to the invention, the counterrollers must be able to exert a sufficient compression for all types of shells to be shaped by the installation, including shells with an inside diameter on the order of 12 mm, which means that the main counterrollers cannot have a diameter greater than 77.6 mm. The maximum diameter of the auxiliary counterrollers is, of course, also limited by the diameter of the shell. However, the calculations show that if according to an embodiment of the invention, the auxiliary counterrollers are put in contact with the shell only when it reaches 200 mm in diameter, with main counterrollers of 77.6 mm in diameter, the theoretical maximum diameter of the auxiliary counterrollers is greater than 700 mm. For practical reasons, and although this theoretically does not correspond to the most favorable conditions for a good shaping of the shells, auxiliary counterrollers of much smaller dimensions are used, for example with a diameter equal to 80 mm.
Now we come to the difficulties posed by the winding itself around a heated revolving mandrel of a section of mineral fibers whose length can amount to about twenty meters, for the purpose of shaping an insulating shell with an outside diameter that can reach up to 500 mm.
As already mentioned, to operate such a winding according to an increasing feeding speed of a felt of mineral fibers with a heated mandrel revolving at a constant speed leads to very great winding times as soon as the outside diameter of the shaped shell exceeds 200 mm, for example. Also according to the invention, operating with a constant feeding speed of felt is selected, and therefore a speed of rotation of the mandrel decreases as the winding progresses.
Theoretically, this rotation speed of the heated mandrel should be equal at each time t to: Vr =Va/πd where Vr is the rotation speed of the mandrel in revolutions per minute, Va the feeding speed of felt in meters per minute and d the outside diameter of the shell in meters at time t. If on the other hand, it is considered that overall, all the wound wraps of felt create an identical increase in the thickness of the shell, or in other words that all the wraps are compressed identically, the value of d is calculated in the following way: ##EQU2## where t e is the time necessary for the total winding of a shell, de the final outside diameter of the shaped shell and d m the diameter of the mandrel around which the felt is wound.
FIG. 5 illustrates the variation, during the winding time, of the outside diameter of the shell (FIG. 5a) and of the corresponding rotation speed of the mandrel (FIG. 5b). Curve 30 corresponds, for example, to the winding, with a constant feeding speed Va =30 m.s 31 1 for a time te A of a shell A with an inside diameter of d m = 12 mm and with an outside diameter d e = 50 mm. Curves 31 and 32 correspond respectively to the winding for a time t eB or t eC of a shell B or C, with d m = 50 mm, d e = 100 mm or d m = 100 mm, d e = 300 mm. It has been found in practice that for the thickness and outside diameter of the shells according to the invention, the representative curve of the diameter is practically a straight line.
From the instantaneous value of diameter d, it is deduced that the theoretical expression of the speed of the mandrel is equal to ##EQU3##
Thus, for each type of shell, the only variable in this expression is time. At 33, 34, 35 the representative curve of this rotation speed of the mandrel V R has been represented as a function of time, respectively for shells A, B and C. First of all, it is found that the production of shells of small inside diameters requires that the mandrel be able to be driven up to a rotation speed close to 800 revolutions per minute. In the other hand, at the end of winding of a shell with an outside diameter of 500 mm, the rotation speed is less than 20 revolutions per minute for a feeding speed of felt kept constant at 30 meters per minute. Such variations of rotation speed make a perfect correlation between the rotation speed of the mandrel and the instantaneous theoretical speed.
According to the invention, care is taken that the real rotation speed of the mandrel be equal to the theoretical rotation speed V R previously calculated at the beginning and at the end of winding. Thus, on the one hand, at the beginning of winding a good anchoring of the first wraps on the mandrel is facilitated and, on the other hand, at the end of winding the formation of folds or unesthetic waves are avoided. Between these two reference values, the speed decreases linearly. This choice is made possible by the elasticity of the material which allows a certain stretching thereof. Moreover, aa already mentioned, the possible increase in the density of the shaped shell has virtually no effect on the conductivity for insulating shells made of glass fibers.
Concerning the counterrollers, we have already indicated that they are withdrawn from the axis of the mandrel as the diameter of the shell being formed increases, while exerting a slight pressure on the shell during the entire time of winding. The pressure exerted by the counterrollers should be such that the outside diameter of the shell conforms well to the desired diameter. To facilitate the anchoring of the first wraps, the counterrollers are preferably driven at a peripheral rotation speed equal to the feeding speed of felt of mineral fibers.
Since a felt of mineral fibers is a very compressible product, a certain pickup of thickness is observed at the end of winding. On the other hand, the more the thickness of wound felts increases, the more the shell being formed is soft and therefore the more it behaves like an elastic material. It is therefore all the more difficult to control the value of the outside diameter of the shell at the end of winding, if it exhibits a significant thickness of wound felt.
If the felts of mineral fibers behaved like a perfectly inelastic material, it would be easily calculated that at each time t, the withdrawal speed v of the counterrollers should be equal to v =(d e 2- d m 2 )/ (4·t e d), where d, dc and dm represents the outside diameter of the shell respectively at time t, -the end of e. and at the beginning of winding and te the time necessary for the winding of the shell. Curve 36 represents this withdrawal speed v as a function of time for the shells of the type B and C previously described.
According to the invention, fixing the real withdrawal speed ve of the counterrollers at the end of winding is selected as being equal to speed v calculated at time t e . Moreover, a linear variation of the withdrawal speed is necessary, slope x being obtained after linearization of the curve v= f(t) or α=(d e 31 d m )/t e 2 -2V e . Curve 37 represents the straight line thus obtained It is found that, at the beginning of winding, the withdrawal speed of the counterrollers is less than the theoretical speed which makes it possible to exert an overcompression which facilitates the formation of a hardened inner surface. It is also possible to increase this overcompression by varying the withdrawal of the counterrollers in relation to the beginning of the winding, as shown in FIG. 6, the counterrollers having a zero withdrawal speed from time t= 0 to t= t'.
This measurement is especially important for shells of rather large thickness, on the order of -2v'100 mm for example, because then the pickup of thickness of the shell becomes very significant as soon as the compression is stopped. To take this into account, it is proposed according to the invention to set a theoretical outside diameter less than the real diameter but which would be obtained after the same winding time. According to the invention, it has been found that in the case of shells of thickness less than 150 mm and of outside diameter not exceeding 500 mm very satisfactory results were obtained with a theoretical diameter equal to 88% of the outside diameter that is desired to be obtained after shaping. In this case, the necessary withdrawal speed of the counterrollers at the end of winding is equal to ##EQU4## an the slope α' equal to:
α'=(de x 0.88 -dm) / te.sup.2 31 2v'.
Thus v'<v, which means a slight overcompression at the end of winding but also α' >means a compression smaller at the beginning of winding compensated for by the delay of the withdrawal of the counterrollers.
This servocontrol obtains an excellent result, i.e., a very good conformity between the measured value of the outside diameter of the shaped shell and the desired value, this of course for outside diameters according to the invention less than 500 mm, and of thicknesses less than 150 mm.
Of course, if shells of greater thicknesses must be shaped with a device of the type described in the invention which is however not preferred, it would then be necessary to select a smaller theoretical value of the outside diameter which will be determined after tests.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | In the manufacture of insulating shells formed by a felt of mineral fibers wound around a mandrel, main pressing elements intervene as soon as the winding begins and remain in contact with the surface of the shell during the entire winding phase. Auxiliary pressing elements intervene only when the shell, during shaping, has reached a given outside diameter of, for example, 200 mm. The invention applies particularly to the insulation of conduits of small and average outside diameters. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] None.
FEDERALLY SPONSORED RESEARCH
[0002] None.
SEQUENCE LISTING
[0003] None.
FIELD OF THE INVENTION
[0004] This invention described below relates to electrically propelled vehicles.
[0005] The invention concerns a system and method of enabling, monitoring and controlling the charge rate of a vehicle/battery by an external third party in order to enable the following:
[0006] 1 Controlling power loading of the grid by controlling the charge rate of electric vehicles/batteries.
[0007] 2 Enabling sliding scale billing rates for the energy supplied for charging the vehicle/battery, dependent on power availability.
[0008] 3 Enabling monitoring and reporting of the energy supplied and used for the purpose of vehicle propulsion, for the reason of calculating tax for energy usage for transportation purposes.
BACKGROUND OF THE INVENTION
[0009] Many vehicles now have the facility for either part electric, or full electric propulsion. Some of these vehicles have the facility to charge up the battery from an external power source. Some vehicles will have interchangeable batteries.
[0010] Whether the battery is fixed or interchangeable, as more and more vehicles convert over to electric propulsion, more loads will be placed on the power system by the requirement for vehicle/battery charging.
[0011] Currently, there are electrical vehicle charging stations in various areas, notably in parking structures at locations such as airports. In general though, the vehicles are charged at the owner/driver's residence or workplace.
[0012] In none of the current electric vehicle/battery charging methods is there a provision for controlling the charge rate of the battery dependent on the power availability of the grid.
[0013] In none of the current vehicle/battery charging systems is there a means of monitoring power used for the purposes of vehicle propulsion, in order to accurately monitor, record and report taxes and charges required by local and federal authorities to replace current gasoline powered vehicle taxes, which are normally paid by way of a per unit charge on gasoline and other fuels.
SUMMARY
[0014] The system and means described below make possible the control of charge rate of electrically propelled vehicles/batteries within a given geographic electrical supply area, in order to control the loading on the electrical grid system. The invention is able to control individual vehicle/battery charging rates dependent on a sliding scale billing system of payments. The invention enables monitoring of energy supplied for vehicle propulsion purposes, in order that such usage may be monitored, reported, billed and taxed accordingly.
[0015] Definitions—List of Terms
[0016] Term: Charge cycle.
[0017] Definition: A period of time during which a vehicle/battery is receiving power for charging.
[0018] Term: Charge rate or charging rate.
[0019] Definition:
[0020] The rate at which a battery is charged up from one level of stored electrical energy to a higher stored level of electrical energy from a power source. The higher the charge rate, the less time taken to fully charge the battery.
[0021] Term: Control system.
[0022] Definition: A device or set of devices to manage, command, direct or regulate the behavior of other devices or systems.
[0023] Term: Charging point.
[0024] Definition:
[0025] A connection point to a power source used for providing power for the charging of an electric vehicle/battery.
[0026] Term: Charging stations.
[0027] Definition:
[0028] Charging points provided specifically for the purposes of charging an electric vehicle/battery.
[0029] Term: Control and monitoring system.
[0030] Definition:
[0031] A system used for the monitoring and control of the charging rate of a vehicle/battery.
[0032] Term: Data transmission.
[0033] Definition: A data transmission is a method of electronic signaling which may be carried out via any convenient means such as, but not restricted to, wire transmission, local or wide area networks, internet communication, telephony, wireless communication, satellite link or other means of achieving a communications link.
[0034] In this disclosure the term data transmission is represented in the diagrams by the following symbols:
[0035] 1:
[0036] 2:
[0037] Term: Electrically propelled vehicle or vehicles.
[0038] Definition:
[0039] A vehicle that can be propelled by means of an electric motor, using energy stored in a battery.
[0040] Term: Geographic electrical supply area or areas.
[0041] Definition:
[0042] A geographic area or areas supplied with electrical power and defined by a power provider.
[0043] Term: Geographic location.
[0044] Definition:
[0045] The physical location; as in a physical street address, a set of GPS (Global Positioning System) co-ordinates or a map reference.
[0046] Term: Geographic power distribution.
[0047] Definition:
[0048] A term used to describe the distribution of power by the power provider between Geographic electrical supply areas.
[0049] Term: Grid.
[0050] Definition:
[0051] See Power network.
[0052] Term: Individual vehicle/battery charge rate.
[0053] Definition:
[0054] A term used to describe a charging rate authorization sent out in a data communication to an individual vehicle/battery.
[0055] Term: Individual vehicle/battery sliding scale billing.
[0056] Definition:
[0057] A sliding scale of charges for the use of electrical power for charging a specific vehicle/battery. A higher sliding scale billing generally would cost more per unit of energy than a low sliding scale billing. This sliding scale charge may be chosen by the owner/driver of the vehicle/battery—in general a high charging rate requirement being charged at a higher rate per unit of energy than a low charging rate requirement.
[0058] Term: Owner/driver
[0059] Definition:
[0060] The person or persons to whom the vehicle/battery energy use is attributed and billed to.
[0061] Term: Power Grid.
[0062] Definition:
[0063] See Power network.
[0064] Term: Power Network.
[0065] Definition:
[0066] The geographic power distribution network of a power provider sometimes referred to as a grid or power grid.
[0067] Term: Power provider or providers.
[0068] Definition:
[0069] A company or companies dealing in the provision and/or sale of electrical power.
[0070] Term: Power provider location.
[0071] Definition: A location from which data signals are sent out to control vehicle/battery charge rates and also receive and record power usage of same, as well as vehicle/battery data for the purposes of billing and taxation.
[0072] Term: Power source.
[0073] Definition:
[0074] A supply of electrical power that can be used for the purposes of charging an electric vehicle/battery.
[0075] Term: Power supply.
[0076] Definition:
[0077] A supply of electrical power that can be used for the purposes of charging an electric vehicle/battery.
[0078] Term: Request for power.
[0079] Definition:
[0080] A data transmission from a vehicle/battery requesting power from a power provider.
[0081] Term: Sliding scale billing.
[0082] Definition:
[0083] A scale of charges by which the power supplied may be charged at a higher or lower rate depending on power availability. For low power availability, high power requirements supplied being billed at a higher per unit rate than low power requirements supplied.
[0084] Term: Supply point.
[0085] Definition:
[0086] A connection point to a power source used for providing power for the charging of an electric vehicle/battery.
[0087] Term: Third party location.
[0088] Definition: A location from which data signals are sent out to control vehicle/battery charge rates; and also receive and record power usage, as well as vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation. This is typically a power provider location but also may be a location provided by local or Federal government for the purposes of monitoring tax, vehicle/battery power usage and vehicle/battery data.
[0089] Term: Vehicle.
[0090] Definition:
[0091] Any form of transportation which can be legally driven on a public road system.
[0092] Term: Vehicle battery.
[0093] Definition:
[0094] A battery that is being used for the provision of propulsion power for an electric vehicle. Such batteries may be charged while attached to the vehicle but in some cases may be charged externally from the vehicle.
[0095] Term: Vehicles/batteries or Vehicle/battery.
[0096] Definition:
[0097] An electrically propelled vehicle or battery used for the provision of propulsion power for an electrically propelled vehicle.
[0098] Term: Vehicle/battery data.
[0099] Definition:
[0100] Data relating to the vehicle or battery being charged. This will include unique identifications for the vehicle and battery and also can contain other information such as registered owner address, odometer reading, power use history, geographic location data and any other data required for the purposes of billing and taxation.
[0101] Term: Vehicle/battery identification.
[0102] Definition:
[0103] A unique identification for a vehicle or a vehicle battery. An example of this would be the VIN number on an automobile.
[0104] Term: Vehicle/battery charging control system or systems.
[0105] Definition:
[0106] A control system which receives signals from a third party and adjusts the rate of charge of a vehicle/battery according to the instructions contained in the signals received.
[0107] Term: Vehicle/battery exemption.
[0108] Definition:
[0109] A vehicle/battery that has been exempted from battery power supply charge rate restrictions due to use. As an example, these would be emergency vehicles.
[0110] Term: Vehicle/battery sliding scale billing subscription.
[0111] Definition:
[0112] A subscription by the vehicle/battery owner/driver that allows a choice of payment levels for vehicle/battery charging. Generally the higher the cost per unit of energy, the faster the charging rate of the vehicle/battery.
BRIEF DESCRIPTION OF THE DRAWINGS
[0113] FIG. 1 is a diagram describing the invention and the way in which the control system of the power provider interacts with individual vehicles/batteries.
[0114] FIG. 2 is a diagram describing an overview of the application of the invention in different geographic areas with vehicles/batteries subscribed at different sliding scale billing rates and including exempt vehicles/batteries.
[0115] FIG. 3 is a diagram describing the way in which the individual vehicles/batteries communicate with, and are monitored and controlled by, the control system of the power providers.
[0116] FIG. 4 is a diagram describing the way in which the control system of the power provider controls and monitors individual vehicles/batteries, records power usage, and generates billing for power usage and taxation purposes.
[0117] FIG. 5 is a diagram describing the control system of the invention based at the vehicle/battery location.
[0118] FIG. 6 is a diagram describing the control system of the invention based at the power provider location.
DETAILED DESCRIPTION OF THE INVENTION
[0119] In use the invention takes the form of a monitoring and control system for the power provider to be able to remotely control the charge rate of, record the amount of power used by, and battery charging rate available to, an electric vehicle/battery.
[0120] FIG. 1 illustrates an embodiment showing a high level view of the process of the interaction between the power provider control system and an individual vehicle/battery. Many of these interactions will take place concurrently, as vehicles/batteries connect to and eventually disconnect from the power supply providers power network.
[0121] In 1100 a vehicle/battery is connected to a power source for the purposes of charging the battery. In 1110 the power connection is detected and in 1120 , data on the geographic location of the vehicle/battery, the vehicle/battery data and any other required information are sent via a data transmission to the power supply provider's control and monitoring system 1130 . The data transmission may be via any convenient means such as, but not restricted to, internet, telephony, wireless communication, satellite link or other available means for achieving a communications link. This is detailed in the definitions section of this document and is hereinafter in this disclosure referred to as “data transmission” without any further references to definition.
[0122] In 1140 the power provider control and monitoring system 1130 receives the request for power. In 1150 a decision is made on the individual vehicle/battery charge rate based on power availability in the geographic location of the vehicle/battery being charged. If power is available for fast charging, the control system sends out a data transmission at 1160 to the vehicle/battery charging control system, allowing the vehicle/battery to be charged at any rate chosen by the vehicle/battery owner/driver.
[0123] If at 1150 power availability is lower than the level that would allow the vehicle/battery to charge at a fast rate, the power provider's control and monitoring system 1130 reviews at 1170 the data for the individual vehicle/battery, which may have been subscribed at a higher sliding scale billing rate, and also checks whether the vehicle/battery is exempt from charging rate restrictions, such as for Government or emergency vehicles/batteries. If the vehicle/battery is subscribed on a higher sliding scale billing rate or is exempt, the control system at 1160 sends out a data transmission to the vehicle/battery allowing the vehicle/battery to be charged at any rate chosen by the owner/driver.
[0124] If, as a result of the review at 1170 , the vehicle/battery is not subscribed at a higher sliding scale billing rate and is not an exempt vehicle/battery, the control system at 1180 sends out a data transmission to the vehicle/battery allowing it to be charged at a rate determined by the power provider, based on geographical power loading and availability.
[0125] At 1190 , the power provider control and monitoring system 1130 reviews available power in the geographic locations on a continuous basis and from time to time may either send out a data transmission allowing vehicles/batteries to increase their charge rates, or decrease their charge rates depending on geographic area power availability.
[0126] The vehicle/battery eventually will be fully charged and the charging control system based at the vehicle/battery will send out a data transmission indicating that the battery is fully charged. If this “fully charged” data transmission for an individual vehicle/battery is received, the power provider control and monitoring system 1130 reviews at 1200 the data for the individual vehicle/battery and at 1210 sends out a data transmission to receive data on power used by the vehicle/battery and ends the charge cycle for the individual vehicle/battery. The power provider control and monitoring system then generates and stores data for power usage, as well as vehicle/battery data, sliding scale billing rate information, geographic location data and any other data required for the purposes of billing and taxation. This will end at 1220 the control and monitoring sequence for an individual vehicle/battery for this charge cycle, until power is again requested.
[0127] FIG. 2 describes an overview of the application of the invention in different geographic areas with vehicles/batteries subscribed at different sliding scale billing rates, and including exempt vehicles. The Geographic areas A and B listed as 2020 and 2030 in the diagram are represented by the dotted/dashed boundary lines around each area. In this illustration only 4 vehicles/batteries are shown in each of two geographic areas connected to 4 supply points in each area. This is for illustration only, as in practice many vehicles/batteries being supplied by many power supply points in many geographic areas will be monitored and controlled. For the purposes of illustration these charging points have been shown as buildings, but in practice may be a charging point in a parking lot, charging station, roadside charging point or other place where an electric vehicle/battery may be connected to a power source in order to charge it. For clarity, only one charging point 2060 , with one connection point 2070 derived from the power provider power line 2040 , is referenced in FIG. 2 , shown connected to vehicle/battery 2080 in geographic area A 2020 . Vehicles/batteries 2090 , 2100 and 2110 are connected in a similar manner, as are the vehicles/batteries 2120 , 2130 , 2140 and 2150 in area B 2030 , although those vehicles/batteries are connected by the power feeds derived from area B 2030 through charging points supplied by power provider line 2050 .
[0128] A power provider 2010 is receiving data transmissions from a number of vehicles/batteries in geographic area A 2020 . At the same time, the power provider 2010 is receiving data transmissions from a number of vehicles/batteries in geographic area B 2030 . Each of these data transmissions contains vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation. The power provider is able to monitor power usage in each of the areas supplied by the power feeds provided to area A 2020 by power line 2040 and also able to monitor power usage in area B 2030 by power line 2050 .
[0129] Each of the vehicles/batteries in area A 2020 are connected to a charging point. As each of the vehicles/batteries is connected, it sends a data transmission containing vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation is sent to the power provider 2010 indicating that the vehicle/battery requires charging. The power provider control system then reviews the individual sliding scale billing subscription for the vehicle/battery being connected, and sends a data transmission back, indicating the rate of charge for the battery allowed, depending on the sliding scale billing subscription, the vehicle/battery exemptions and the power loading of area A 2020 . Thus each of the vehicle/batteries 2080 , 2090 , 2100 and 2110 will be receiving individual data transmissions containing power charging rate instructions from the power provider, the instruction depending on the factors of individual vehicle/battery sliding scale billing subscription, vehicle/battery exemptions and the power loading of area A 2020 .
[0130] The vehicles/batteries 2120 , 2130 , 2140 and 2150 in area B 2030 will also be receiving individual data transmissions containing charging rate instructions from the power provider, the instruction depending on the factors of individual vehicle/battery sliding scale billing subscription, vehicle/battery exemptions and the power loading of area B 2030 .
[0131] Each of the individual vehicles/batteries in both areas A 2020 and B 2030 will receive update data transmissions from the power provider, allowing them to alter their vehicle/battery charging rates, as power loading in areas A 2020 and B 2030 allow. In every individual case, the data contained in the data transmission will control the maximum vehicle/battery charging rate. Should the owner/driver require a lower charging rate than the one authorized, the vehicle/battery control system will default to the lower charging rate.
[0132] In this manner, power loading in areas A 2020 and B 2030 are controlled by the power provider 2010 , and also allow power supplied for vehicle/battery charging to be recorded and billed, along with any Federal or local taxation requirements for power supplied.
[0133] FIG. 3 Describes the way in which the individual vehicle/battery charging control systems communicate with and are monitored and controlled by the control system of the power providers.
[0134] In 3010 the vehicle/battery is connected to a power source for the purposes of charging the vehicle/battery. In 3020 the power connection is detected by the control system and in 3030 the control system measures and assesses the vehicle/battery charging requirements.
[0135] In 3040 the control system sends a data transmission to the power provider, the data including battery charge state, geographic location, vehicle/battery data, plus any other data required by the power provider. In 3050 the control system checks to see if a response has been made for charging instructions by data transmission from the power provider. If the instructions have not been received, the control system checks the number of times the request has been sent out at 3060 . If a pre-determined number of data transmission communication attempts have not been exceeded the system sends out a further request at 3040 and cycles back through steps 3050 to 3060 . If the pre-determined number of data communications is exceeded at step 3060 , the control system commences charging the vehicle/battery at 3070 at the maximum rate requested by the vehicle/battery owner/driver. In the case of this communication failure with the power provider, the vehicle/battery charging control system will record and store the power usage along with vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation and report it to the power provider at the next successful communication for billing purposes. This stored data can also be accessed at any time by an authorized third party location for the purposes of mileage and power use verification.
[0136] If at 3050 the data transmission from the power provider has been received, then the control system enables charging the vehicle/battery at 3080 at the charge rates transmitted by the power provider.
[0137] At 3090 , the control system is monitoring the power input; should the vehicle/battery become disconnected, the control system will send a data transmission to the power provider at 3130 and stops the charging system at 3140 . Should the power be re-applied, the system will default to step 3010 . All power use events will be recorded by the control system. This stored data along with vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation, can also be accessed at any time by an authorized third party location for the purposes of mileage and power use verification.
[0138] At 3090 if the control system indicates that the power is still connected, the control system at 3100 receives updates from the power provider control system by way of data transmission which will adjust the charge rate of the vehicle/battery up or down depending on the power loading in the geographic area up to the maximum charge rate requested by the vehicle/battery owner/driver.
[0139] At 3110 , the control system checks whether the vehicle/battery is fully charged. If the battery is not fully charged the system cycles back through steps 3090 to 3110 until the vehicle/battery is fully charged. Once it is established that the vehicle/battery is fully charged at 3110 , the control system stops charging the vehicle/battery at 3120 and sends a data transmission containing data on power used, vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation to the power provider at 3130 , the system then stops at 3140 until the next time the vehicle/battery is connected to a charging point. All power use events will be recorded by the control system. The stored power use data as well as vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation can also be accessed at any time by an authorized third party location for the purposes of mileage and power use verification.
[0140] FIG. 4 describes the way in which the control system of the power provider controls and monitors individual vehicles/batteries, recording power usage and generating billing for power usage and taxation purposes.
[0141] At 4010 , the control system is receiving data on geographic area power utilization and availability.
[0142] At 4020 , the control system is receiving vehicle/battery data, geographic location data, and any other data required for the purposes of billing and taxation from individual vehicles/batteries requiring power for charging as they are connected to the system.
[0143] At 4030 , the system checks to see whether the vehicle/battery is registered at a high sliding scale billing rate, or is an exempted vehicle/battery. If either of these checks is positive the control system sends out a data transmission at 4050 to the vehicle/battery to commence charging at the maximum rate requested by the owner/ driver of the vehicle/battery. At 4030 , if the vehicle/battery is not exempt and is not subscribed at a high sliding scale billing rate the control system sends out a data transmission to the vehicle/battery at 4040 to commence charging at a rate based on power availability in the geographic area within which the vehicle/battery is located.
[0144] At 4060 , the control system receives updates on the power distribution loading for the geographic area and sends out data transmissions, instructing vehicles/batteries connected to the power system to vary their charge rates depending on the loading on the system and power availability.
[0145] At 4070 , as individual vehicles/batteries become fully charged they disconnect from the supply after sending out power use data, vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation. At 4080 , the control system stores the data on power supplied, sliding scale billing rates, vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation. At 4090 , the control system interfaces with the billing system to generate individual vehicle/battery power use and tax billing.
[0146] At 4070 , the system cycles back through to 4010 since the localized power provider control sequence is continuous with vehicles/batteries being connected and disconnected from the network as they require charging.
[0147] FIG. 5 is a block diagram describing the control system of the invention based at the vehicle/battery location. In practice the major blocks of this system are contained within the vehicle/battery.
[0148] When the vehicle/battery is connected to a power source the power detection module 5010 detects the connection and sends a signal to the data handling module 5020 . The data handling module 5020 retrieves the unique vehicle/battery data from the identification module 5030 and requests data from the power control module 5040 . The power control module 5040 requests and receives data from the battery charge state monitoring module 5050 . The power control module 5040 sends the battery status to the data handling module 5020 . The data handling module 5020 then sends all of this data plus geographic location data from the geographic location module 5025 via the security module 5070 to the communications module 5080 which sends a data transmission to the power provider.
[0149] When the power provider sends back a data transmission containing battery charging rate data, it is received by the communications module 5080 and is passed via the security module 5070 to the Data handling module 5020 . The information is passed from the data handling module 5020 , to the power control module 5040 , which then controls the charge rate of the power supply for charging battery 5090 , to charge at the rate authorized by the power provider.
[0150] The battery charge state module 5050 monitors the battery 5060 charge state continuously, and once the battery 5060 is fully charged sends a signal to the power control module 5040 which instructs the power supply 5090 to stop charging. The power control module 5040 also sends data to the data handling module 5020 which sends information on power used, vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation to the communications module 5080 via the security module 5070 . The communications module sends a data transmission containing this data to the power provider. The control system stores power used, vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation, so that it can also be accessed at any time by an authorized third party location for the purposes of mileage and power use verification.
[0151] The power provider sends back an acknowledgement data transmission and the control system resets until the next time a power connection event is detected at 5010 .
[0152] In the event that there is no communication possible at the end of the battery charge cycle described above or if no acknowledgement is received, the power use data will be stored along with vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation, to be transmitted when communications between the control system and the power provider are restored. The control system stores power usage vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation so that it can also be accessed at any time by an authorized third party location for the purposes of mileage and power use verification.
[0153] FIG. 6 is a block diagram describing the control system of the invention based at the power provider location.
[0154] The communications module 6010 receives data transmission signals from individual vehicles/batteries requesting power, and also containing vehicle/battery data, geographic location data and any other data required for the purposes of billing and taxation. The communications module 6010 communicates the data transmission to the data handling module 6030 via a security module 6020 . The data handling module 6030 is also receiving Geographic area power availability data from 6050 directly from the power provider via a security module 6040 .
[0155] The data handling module 6030 receives the individual vehicle/battery power request and retrieves vehicle/battery sliding scale billing subscription data, and where appropriate exemption data from the Sliding scale billing subscription and exempt vehicle/battery registry module 6060 .
[0156] Based on all available data, the data handling module 6030 then sends out a data transmission containing charge rate authorization to the individual vehicle/battery, based on power availability in the geographic area, individual vehicle/battery Sliding scale billing subscription data, and vehicle/battery exemption status. This data is sent from the data handling module 6030 via the security module 6020 to the communications module 6010 which sends the data transmission to the individual vehicle/battery.
[0157] If the power to the individual vehicle/battery is disconnected or if the vehicle/battery has completed charging, a data transmission containing power use data, vehicle/battery data, geographic location data, and any other data required for the purposes of billing and taxation, is sent from the control system of the vehicle/battery, which is received by the communications module 6010 and sent via the security module 6020 to the data handling module 6030 . The data handling module 6030 sends the data to the vehicle/battery power usage data storage module 6070 where it can be accessed periodically for billing/taxation purposes by the power provider billing module 6080 .
[0158] The system will from time to time send out data transmissions to the individual vehicles/batteries in order to adjust the power grid loading in the geographic area, reducing individual vehicle/battery charge rates at high loading times and allowing increased charge rates at times when more power in the Geographic area is available.
[0159] The vehicle/battery owner/driver is able to control subscription rates for power used by the vehicle/battery by means of subscribing to different sliding scale billing rates via a secure web subscriber interface portal 6090 . Additionally there is an interface at 6110 to enable the power provider to interface with and make adjustments to the control system and the data contained within it. | A system and means for controlling, monitoring, recording and reporting the use of power supplied for battery charging in electrically powered vehicles and their batteries; for the purposes of adjusting power loading on the electrical supply system, as well as allowing monitoring, recording, reporting and billing for such power use, and for recording, reporting and billing local and federal taxes for use of such electrical energy used for vehicle propulsion purposes. | 8 |
The present invention relates to an apparatus for creating a sub-channel in a main channel of the type, for example, that supports communications between a first network node and a second network node. The present invention also relates to a communications system for supporting a sub-channel within a main channel of the type, for example, that supports communications between a first network node and a second network node. The present invention further relates to a method of creating a sub-channel within a main channel of the type, for example, that supports communications between a first network node and a second network node.
BACKGROUND ART
In the field of network communications, it is known to implement passive measurement techniques at selected points in a communications network in order to monitor Quality of Service levels and diagnose faults that can occur from time-to-time in the communications network.
In this respect, it is known to deploy so-called “passive probes” at the selected points in the communications network. Such passive probes make measurements relating to network traffic travelling along one or more links in the communications network. Additionally, once collected, measurement data has to be communicated to, for example, a central monitoring station in the communications network for analysis and interpretation.
In order to convey the measurement data from a passive probe to the central monitoring station, US 2005/0083957 A1 proposes a low bandwidth channel formed by inserting packets into a high bandwidth packet stream. The packets are inserted at a predetermined interval, insertion causing latency that is recovered by minimising inter-packet gaps in the incoming high bandwidth channel. While the packets to be inserted are being transmitted, arriving high bandwidth packets are stored in an elastic buffer.
However, whilst the above technique provides a mechanism for achieving the low bandwidth channel in the high bandwidth packet stream, it is desirable to improve performance of the low bandwidth channel. In particular, the above-described technique relies upon the existence of sufficiently large “gaps” in the high bandwidth data stream that can be reduced to allocate bandwidth to accommodate transmission time for the low bandwidth channel. However, the above apparatus preserves traffic flow in the high bandwidth data stream as the traffic in the high bandwidth data stream is considered to be of greater importance than the traffic using the low bandwidth channel. This is an overriding principle to which operation of the above apparatus adheres. Hence, if insufficient gaps exist in the high bandwidth data stream, transmissions on the low bandwidth channel have to be halted due to lack of bandwidth until a sufficiently large gap occurs in the high bandwidth stream.
As a result of a temporary incapability to transmit on the low bandwidth channel, it is necessary to buffer the measurement data to be transmitted until the measurement data can be transmitted. Whilst the apparatus described above comprises the elastic buffer, there is a limit to elasticity of the buffer. To avoid running out of buffer capacity, the apparatus reaches a point where creation of new packets has to be temporarily halted until bandwidth becomes available to resume transmission of the measurement data. Alternatively, the apparatus discards packets already created (and in the buffer) in order to provide capacity in the buffer for newly created packets containing measurement data.
SUMMARY OF THE DISCLOSED EMBODIMENTS
According to a first aspect of the present invention, there is provided an apparatus for creating a sub-channel within a main channel between a first network node and a second network node, the apparatus comprising: a data store for temporarily storing sub-channel data; a processing resource for monitoring downstream communication from the first network node, the processing resource being arranged, when in use, to identify a suitable channel condition in the downstream communication, and to determine whether insufficient time exists to await probabilistic occurrence of the suitable channel condition before a deadline to transmit the sub-channel data is reached, the suitable channel condition supporting initiation of transmission of the sub-channel data in place of at least part of data for signifying an idle period in the downstream communications; wherein the processing resource is further arranged to transmit upstream, when in use, a flow control message for receipt by the first network node, thereby causing timely generation of the suitable channel condition before the deadline.
The processing resource may be arranged to identify, when in use, the at least part of the data for signifying the idle period in the downstream communication, and to determine whether insufficient time exists to await probabilistic occurrence of a subsequent idle period before the deadline to transmit the sub-channel data is reached, the subsequent idle period being required when the data for signifying the idle period does not correspond to at least a predetermined suitable minimum duration to support the initiation of transmission of the sub-channel data in place of the at least part of the data for signifying the idle period; and the timely generation of the suitable channel condition is timely generation of at least part of the subsequent idle period before the deadline, the at least part of the subsequent idle period having at least the predetermined suitable minimum duration.
The processing resource may be further arranged to initiate transmission of the sub-channel data in place of subsequent data for signifying the at least part of the subsequent idle period.
The processing resource may be arranged to determine whether the data for signifying the idle period does not correspond to at least an average duration to support the initiation of transmission of the sub-channel data.
The apparatus may further comprise: memory operable to hold an extra packet constituting the sub-channel data; memory operable to hold a parallel datastream while the extra packet is being sent; and control logic.
The apparatus may further comprise a deserialiser operable to convert a serial datastream to the parallel datastream for the downstream communications on the main channel, and a serialiser operable to convert the parallel datastream back to the serial datastream.
The processing resource may be arranged to determine whether flow control is supported for the downstream communications on the main channel. A time limit may be associated with the flow control message.
The processing resource may be arranged to allow the time limit to expire.
The processing resource may be arranged to send a subsequent flow control message for receipt by the first network node, thereby terminating the subsequent idle period. A substantially zero time limit may be associated with the subsequent flow control message.
According to a second aspect of the present invention, there is provided a probe for monitoring signals in a communications network, the probe comprising the apparatus as set forth above in relation to the first aspect of the invention.
According to a third aspect of the present invention, there is provided an interface converter module comprising the apparatus as set forth above in relation to the first aspect of the invention.
According to a fourth aspect of the present invention, there is provided a communications system for supporting a sub-channel within a main channel, the system comprising: a first network node and a second network node for supporting the main channel therebetween; a data store for temporarily storing sub-channel data; a network monitoring apparatus for monitoring downstream communications from the first network node, the network monitoring apparatus being arranged to identify, when in use, a suitable channel condition in the downstream communications, and to determine whether insufficient time exists to await probabilistic occurrence of the suitable channel condition before a deadline to transmit the sub-channel data is reached, the suitable channel condition supporting initiation of transmission of the sub-channel data in place of at least part of data for signifying an idle period in the downstream communications; wherein the network monitoring apparatus is further arranged to transmit, when in use, a flow control message to the first network node, thereby causing timely generation of the suitable channel condition before the deadline.
According to a fifth aspect of the present invention, there is provided a method of creating a sub-channel within a main channel between a first network node and a second network node, the method comprising: temporarily storing sub-channel data; monitoring downstream communications from the first network node; identifying a suitable channel condition in the downstream communications; determining whether insufficient time exists to await probabilistic occurrence of the suitable channel condition before a deadline to transmit the sub-channel data is reached, the suitable channel condition supporting initiation of transmission of the sub-channel data in place of at least part of data for signifying an idle period; and transmitting upstream a flow control message for receipt by the first network node, thereby causing timely generation of the suitable channel condition before the deadline.
According to a sixth aspect of the present invention, there is provided a computer program element comprising computer program code means to make a computer execute the method as set forth above in relation to the fifth aspect of the invention.
The computer program code element may be embodied on a computer readable medium.
It is thus possible to provide a system, apparatus and method therefor that are capable of creating opportunities to send the sub-channel data when at least one channel condition is insufficient, for example the idle periods detected are of insufficient length, to support initiation of transmission of the sub-channel data and a sufficiently long idle period cannot be awaited, for example due to a constraint, such as a buffer size. Data loss in relation to the sub-channel can therefore be obviated or at least mitigated. It is also possible to send, with minimal delay, high priority data, such as an alarm message, without having to wait for sufficiently large gaps in the datastream of the main channel.
BRIEF DESCRIPTION OF DRAWINGS
At least one embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a communications system comprising a communications apparatus constituting an embodiment of the invention;
FIG. 2 is a schematic diagram of the communications apparatus of FIG. 1 in greater detail;
FIG. 3 is a flow diagram of a method employed by the communications apparatus of FIG. 1 and FIG. 2 ; and
FIG. 4 is an event timing diagram of repeated invocations of the method of FIG. 3 .
DETAILED DESCRIPTION
Throughout the following description identical reference numerals will be used to identify like parts.
Referring to FIG. 1 , a communications system 100 comprises a first network node, for example a first host 102 capable of communicating with a second network node, for example a second host 104 . The first host 102 is therefore coupled to the second host 104 by a first unidirectional communications link 106 in a first direction and a second unidirectional communications link 108 in a second direction opposite to the first direction, thereby providing communications media for bi-directional communications. In this example, the first host 102 is a first router and the second host 104 is a second router, the first and second routers together providing connectivity between domains (not shown) in a communications network (also not shown). However, the skilled person will appreciate that the first and second hosts 102 , 104 can be other functional pairs of communications elements, for example an Ethernet card in a Personal Computer and a router.
The first and second unidirectional communications links 106 , 108 are each supported, in this example, by a respective optical fibre. A first main communications channel is supported by the first unidirectional communications link 106 and a second main communications channel is supported by the second unidirectional communications link 108 .
In order to support a first sub-channel in the first main channel, and a second sub-channel in the second main channel, an in-line sub-channel apparatus 110 of the type described in EP-A1-1 524 807 is disposed in the first and second communications links 106 , 108 between the first and second hosts 102 , 104 . Although the structure and operation of the in-line sub-channel apparatus 110 is well-documented in EP-A1-1 524 807, for the sake of ease of reference and ready understanding of the additional and/or alternative functionality described later herein, the structure of the in-line sub-channel apparatus 110 will now be briefly described.
The in-line sub-channel apparatus 110 comprises a first sub-channel injector 112 coupled to an application logic 114 that uses the first sub-channel supported by the first sub-channel injector 112 . In contrast with EP-A1-1 524 807, the in-line sub-channel apparatus 110 also comprises a second sub-channel injector 116 coupled to the application logic 114 as the application logic 114 also uses, in this example, the second sub-channel supported by the second sub-channel injector 116 . Since the second sub-channel injector 116 is a reverse-direction implementation of the first sub-channel injector 112 , the second sub-channel injector 116 will not be described further except in passing reference, since the skilled person will appreciate the structure and functions of the second sub-channel injector 116 from a description of the first sub-channel injector 112 . Consequently, for the sake of simplicity and conciseness of description, the “first main channel” will now be referred to as the “main channel”, and the “first sub-channel” will now be referred to as the “sub-channel” as no further references will be made herein to the second main channel or the second sub-channel.
Turning to FIG. 2 , the application logic 114 is coupled to a datastream input 200 of the first sub-channel injector 112 . The datastream input 200 is also coupled to an input of an idle deletion module 202 and a first input of a first multiplexer 204 . An output of the idle deletion module 202 is coupled to a first input of a second multiplexer 206 , a second input of the second multiplexer 206 being coupled to an internal buffer 207 of the application logic 114 . An output of the second multiplexer 206 is coupled to an input of a First-In-First-Out (FIFO) buffer 208 , an output of the FIFO buffer 208 being coupled to a second input of the first multiplexer 204 .
Although not shown and not required if data is to be processed in serial form, a de-serialiser module is coupled before the datastream input 200 to perform a serial-to-parallel conversion on incoming data arriving at the first sub-channel injector 112 and a serialiser module is coupled to an output of the first multiplexer 204 to perform a parallel-to-serial conversion on outgoing data leaving the first sub-channel injector 112 .
In operation, the communications system 100 supports a Gigabit Ethernet protocol in accordance with the Institute of Electrical and Electronic Engineers (IEEE) Standard 802.3 and the in-line sub-channel apparatus 110 is capable of functioning in a manner described in EP-A1-1 524 807. However, the skilled person will recognize that the functionality of the in-line sub-channel apparatus 110 can be modified to include only some of the functionality described in EP-A1-1 524 807. Likewise, in the present example, the functionality of the in-line sub-channel apparatus 110 can be modified to enhance functionality of the in-line sub-channel apparatus 110 .
In this respect, the in-line sub-channel apparatus 110 is part of a communications monitoring apparatus (not shown), for example a probe, such as any suitable probe for measuring network performance, that generates measurement data in relation to a given communications link, for example the first unidirectional communications link 106 . In this example, the measurement data generated has to be forwarded to a central monitoring station for analysis in order to monitor Quality of Service of, inter alia, the communications system 100 and diagnose any faults. The measurement data generated has to be stored temporarily as packetised data by the application logic 114 for onward transmission. However, the storage capacity of application logic 114 is finite and the application logic 114 has to await suitable channel conditions in order to be able to inject at least one packet into a datastream on the main channel, the datastream being transmitted from the first host 102 to the second host 104 .
When the first host 102 does not need to communicate with the second host 104 , the first host 102 , instead of simply remaining inactive during an idle period, sends data signifying the idle period in the datastream to the second host 104 in accordance with the IEEE 802.3 standard. As described in EP-A1-1 524 807, the in-line sub-channel apparatus 110 exploits idle periods on the main channel to support the sub-channel.
Turning to FIG. 3 , the application logic 114 monitors the internal buffer 207 in order to determine ( 300 ) whether the internal buffer 207 has packets containing measurement data to be sent. If the internal buffer 207 is empty, the application logic 114 continues monitoring the status of the internal buffer 207 . Referring to FIG. 4 , in accordance with a by-pass mode, an incoming frame of data 400 is received ( 402 ) by the in-line sub-channel apparatus 110 . The incoming frame of data 400 is passed to the first multiplexer 204 without further interference, and hence delay, caused by the application logic 114 , whereupon an output frame 403 , constituting an unmodified version of the incoming frame of data 400 , is sent by the in-line sub-channel apparatus 110 for receipt ( 404 ) by the second host 104 . Referring back to FIG. 3 , in the event that the internal buffer 207 contains one or more packet to be transmitted using the sub-channel, the application logic 114 determines ( 302 ) whether conditions on the main channel are suitable to support initiation of transmission of at least one packet being stored by the internal buffer 207 . Consequently, the data signifying the idle period must be detected and, for example, occurrences of idle periods on the main channel may not be of sufficient length to support initiation of transmission of at least part of the sub-channel data, i.e. data stored by the internal buffer 207 . Another condition that may need to be met (depending upon system requirements) is whether a so-called “hold timer”, as described in EP-A1-1 524 807, has expired. Additionally or alternatively, the condition can be whether a detected idle period exceeds a calculated average duration. In this example, for the sake of simplicity of description, the application logic 114 only verifies if a detected idle period, identified by data codes conforming to the IEEE 802.3 standard, is greater than a predetermined minimum suitable duration.
If the idle period is greater than the predetermined minimum suitable duration, the in-line sub-channel apparatus 110 sends ( 306 ) the at least part of the sub-channel data in accordance with the technique described in EP-A1-1 524 807 and depending upon the capacity of the FIFO buffer 208 . On the other hand, if the conditions on the main channel are not suitable, for example the above minimum duration condition has not been met, the application logic 114 determines ( 306 ) whether waiting a predetermined delay period is permissible, for example without resulting in overflow of the internal buffer 207 . The occurrence of the suitable channel condition is, of course, probabilistic. However, if it is possible to wait the predetermined delay period, the application logic 114 abstains ( 307 ) from sending the at least part of the sub-channel data for the predetermined delay period and then reverts to determining ( 302 ) whether the conditions on the main channel are now suitable for implementing the sub-channel.
If it is not possible to delay transmission on the sub-channel without a resulting overflow of the internal buffer 207 , the application logic 114 determines ( 308 ) whether a flow control message has been sent to the first host 102 , for example a Media Access Control (MAC) Pause frame. The above use of flow control in the communications system 100 is aspirational on the part of the in-line sub-channel apparatus 110 and so verification that the flow control message has been sent has to take place in order to ascertain whether the flow control is being employed between the first and second hosts 102 , 104 . In this respect, symmetric flow control can be in operation if flow control is supported by both the first and second hosts 102 , 104 or asymmetric flow control can be in operation if flow control is only supported by the first host 102 . However, if only the second host 104 supports flow control or neither the first host 102 nor the second host 104 support flow control, then the in-line sub-channel apparatus 110 has to provide a mechanism alternate to that described herein to avoid overflow of the internal buffer 207 , otherwise overflow is risked. The application logic 114 can, of course in another embodiment, be configured to detect whether the first host 102 , the second host 104 , both or neither support flow control by monitoring, for example an autonegotiation procedure between the first and second hosts 102 , 104 at start-up of the first and/or second host 102 , 104 , but such a monitoring facility is not essential and the implementation described herein based upon an optimistic attitude to implementation of flow control is adequate.
In the event that control of the datastream transmitted by the first host 102 is not possible, the application logic 114 is implicitly “aware” of the lack of flow control support by the first host 102 by virtue of the flow control message already having been sent. Recordal of prior use of the flow control message is recorded by a flag (not shown).
Hence, if the flow control message has already been sent once and the conditions on the main channel remain unchanged, flow control is assumed currently not to be implemented by the first host 102 and the application logic 114 has no choice but to drop ( 310 ) a packet from the internal buffer 207 in order to avoid overflow thereof (assuming no alternative mechanism has been implemented). The flag is then cleared ( 312 ) by the application logic 114 and the application logic 114 reverts to determining ( 300 ) whether further packets need to be sent, but are currently stored in the internal buffer 207 .
Alternatively, if the flag has not been previously set, indicting that transmission of the flow control message has not been attempted in respect of the at least part of the sub-channel data that needs to be sent, the application logic 114 , using the second sub-channel injector 116 , sends ( 314 ) the flow control message 406 ( FIG. 4 ) containing a pause duration of a value, for example, sufficiently large to enable transmission of the at least part of the sub-channel data to the first host 102 , and then sets ( 316 ) the flag to indicate that the flow control message has been sent and then awaits at least one suitable channel condition, for example detection of idle code groups.
In response to the MAC Pause frame, the first host 102 finishes sending any frames currently in the process of transmission and then sends so-called IDLE characters in place of frames of data, i.e. data signifying a subsequent idle period, corresponding to the pause duration.
The application logic 114 , which has now returned to determining ( 302 ) whether conditions on the main channel are now suitable for sending the at least part of the sub-channel data, detects the IDLE characters received, the IDLE characters corresponding to the pause duration that is greater than the predetermined minimum suitable duration. Consequently, the in-line sub-channel apparatus 110 is able to send ( 306 ) the at least part of the sub-channel data in a manner described in EP-A1-1 524 807. In this example, a first packet 408 containing first measurement data is sent, followed by a second packet 410 containing second measurement data. Thus, timely removal of data from the internal buffer 207 is achieved, thereby avoiding overflow of the internal buffer 207 .
Referring back to FIG. 4 , once sufficient sub-channel data to provide overflow relief to the internal buffer 207 has been sent, the in-line sub-channel apparatus 110 can revert to the operation described in EP-A1-1 524 807 (modified in whatever way so desired) as sufficient time now exists to await suitable conditions on the main channel. In this respect, the in-line sub-channel apparatus 110 can continue implementing the pass-through mode to let data frames 412 transmitted by the first host 102 to the second host 104 pass through the in-line sub-channel apparatus 110 without delay.
Any subsequent need 414 to force idle periods in the datastream from the first host 102 can be implemented in the manner already described above.
However, excessively long pause durations or excessive use of flow control messages within a given period of time can result in excessive dropping of packets or permanent changes to routing tables by routers as a result of an inference by the routers of an existence of a downstream communications problem. Therefore, the application logic 114 can be arranged to estimate a required pause duration for injecting one or more packets that needs to be sent. If appropriate, the estimated pause duration is incorporated into the Pause control frame. The estimated pause duration can be deemed appropriate if a suitable predetermined interval of time has elapsed since transmission of a previous Pause control frame.
Of course, it should also be appreciated that if the in-line sub-channel apparatus 110 finishes transmitting sub-channel data before expiry of the pause duration, a subsequent flow control message can be sent to the first host 102 having a reduced pause duration of substantially zero time, the reduced pause duration superseding the existing pause duration being implemented and resulting in resumption of transmission of data frames from the first host 102 to the second host 104 in accordance with the IEEE 802.3 standard.
Although the above examples have been described in the context of packet communications, it should be appreciated that the term “message” is intended to the construed as embracing packets, datagrams, frames, cells and/or protocol data units and so these terms should be understood to be interchangeable. Therefore, in the context as described herein, it should be understood that a “packet” is not just an IP packet but it is a frame that can contain an IP packet. In the case of Ethernet, it is an Ethernet frame that may already be encoded, for example using 8B/10B encoding. The type of encoding will depend on encoding techniques used by passing traffic on the main channel.
Whilst it has been suggested above that the in-line sub-channel apparatus is implemented in a probe, the skilled person will appreciate that the in-line sub-channel apparatus 110 can be implemented in various forms, for example in a highly integrated form suitable for replacing industry-standard interface converter modules, for example those known as GigaBit Interface Converters (GBICs). Current GBICs are effectively transceivers that translate signals of one media type, for example optical or electrical, to another media type. By providing a replacement GBIC including the in-line sub-channel apparatus, numerous applications requiring sub-channels are further enabled.
Alternative embodiments of the invention can be implemented as a computer program product for use with a computer system, the computer program product being, for example, a series of computer instructions stored on a tangible data recording medium, such as a diskette, CD-ROM, ROM, or fixed disk. The series of computer instructions can constitute all or part of the functionality described above, and can also be stored in any memory device, volatile or non-volatile, such as semiconductor, magnetic, optical or other memory device. | A communications apparatus includes an input for receiving a data stream being transmitted from a first network node to a second network node using a main channel. A processing resource of the communications apparatus identifies data signifying an idle period within the data stream and determines whether the idle period is at least a suitable minimum duration to support initiating transmission of sub-channel data in place of at least part of the data signifying the idle period. Further, the processing resource is arranged to identify when the idle period is not of the suitable minimum duration and a need arises to transmit the sub-channel data within a predetermined period of time. In such circumstances, the processing resource sends a flow control message upstream to the first network node to halt transmissions therefrom, thereby generating the idle period of at least the suitable minimum duration. | 7 |
BACKGROUND OF THE INVENTION
A. Field of the Invention
The field of this invention is motion simulators. More particularly and in the preferred embodiment, the invention is a motion simulator which provides (1) full 360 degree roll capability combined with forward/backward, lateral, and up/down motion, (2) size that permits portability, (3) and simple, reliable operation. The motion system is controlled externally by a preprogrammed set of commands executed by an external Processing Unit. The motion system will seat multiple rows of passengers and when combined with a visual display system and sound system, will provide a complete simulation environment to the passengers.
As a motion simulator, this invention is used to provide motion sensations to passengers riding inside the simulator. This motion simulator is used primarily in entertainment applications, such as in amusement parks. During operation the passengers ride inside a capsule, observing a visual scene on a display screen at the front of the capsule and hearing sound from speakers placed inside the capsule. The motion simulator moves the capsule in synchronization with the displayed visual scene, greatly enhancing the realism and quality of the entertainment experience.
B. Description of Related Art
It is desirable in providing a simulation environment to provide physical motion to the passengers. This motion adds to the realism of the simulation experience. A variety of motion devices have been developed to meet this need. Degrees of movement within motion simulators has traditionally been described in terms of the number of "degrees of freedom" (DOF). A 3-DOF motion base would provide heave (up and down), roll (tipping down on either side) and pitch (tipping down in the front or the back). A 4-DOF motion base would add surge (linear forward and backward) with a 6-DOF motion base adding sway (twisting the front or rear sideways) and linear sideways movement. Generally, the prior art devices fall into one of three categories, which can be classified as pivot type, bench type and sled type simulators.
Pivot type simulators typically use actuators positioned underneath the motion platform. Seats for passengers ar placed on top of the platform. Sometimes these seats are enclosed in a compartment, sometimes the these seats are open as within a theater. Movement within a pivot type simulator depends on the particular design, with 3, 4, and 6-DOF motion systems available. Pivot type simulators generally are complicated devices with a large number of mechanical actuator components requiring extensive control systems because each movement requires a coordinated movement of all the actuators of the platform.
Bench type simulators are available in a variety of forms, with the most common being a row of seats which can move up and down, tilt from side to side, and tip toward the front or the back. In some variations, the individual seats have limited independent, synchronized shaking motion as well. Most bench type simulators have open seats with imagery projected onto a fixed screen in a theater type environment.
Sled type simulators come in a large variety of forms but all tend to move the passenger compartment by pitching, down on either side, and/or tipping, up or down in the front or back. Typically sled type simulators operate in a bowl, on a track or on a pivot point. These devices are the closest to the traditional amusement park or arcade rides and may or may not be combined with a imagery system as a part of the simulation.
There have also been designs for simulators based on suspending the passenger compartment from above, whereby actuators suspended from a frame support and control the movement of the passenger compartment. The inventors know of no production models or patents for this type of motion system simulator but believe such a design may exist.
The following patents describe inventions which constitute the most pertinent prior art that the applicant is aware of.
U.S. Pat. No. 4,066,256, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Trumbull describes an amusement ride that uses three hydraulic rams that can tilt the passenger frame or move it up or down.
U.S. Pat. No. 4,251,140, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Fogerty describes a ride assembly for simulating travel that uses carriage members to provide pitching and rolling, in limited degrees, to a passenger housing.
U.S. Pat. No. 4,303,236, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Czarnecki describes a trip motion simulator which provides motion to a people-holding capsule by supporting the capsule on pitch and roll cradles, with the cradles themselves mounted on a platform that permits fore and aft as well as side to side motion.
U.S. Pat. No. 4,461,470, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Astroth et al. describes a system for adding realism to video display which uses a platform mechanism to tilt the single passenger seat while moving the views on the video display accordingly.
U.S. Pat. No. 4,642,945, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Browning et al. describes an entertainment structure in which the seats in an auditorium are tilted and rotated to enhance the visual presentation.
U.S. Pat. No. 4,710,128, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Wachsmuth et al. describes a spatial disorientation trainer-flight simulator which uses a cockpit gimbaled on three independently controlled axes, ie., pitch, roll and yaw, revolving about a planetary axis.
U.S. Pat. No. 4,710,129, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Newman et al. describes a simulation device in which a passenger cabin is mounted on a pivoting structure providing pivoting and pitching motion to the passenger, under passenger control as part of a video arcade game.
U.S. Pat. No. 4,856,771, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Nelson et al. describes a video simulation apparatus. This machine has an enclosed cockpit containing movement controls and may be occupied by one or two persons.
U.S. Pat. No. 4,874,162, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Trumbull et al. describes an amusement ride of the type that moves and tilts passengers viewing a motion picture.
U.S. Pat. No. 4,879,849, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Hollingsworth III et al. describes a point of view motion simulator system to be used essentially for applying motion to seats within a motion picture theater.
U.S. Pat. No. 4,885,878, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Wuu describes a movie theater where the seats are attached to a movable platform which provides tilting motion to participants of the ride.
U.S. Pat. No. 5,015,933, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Watkins et al. describes a seat base motion controller for providing seat motion for seat motion systems used in amusement rides and the like.
U.S. Pat. No. 5,060,932, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Yamaguchi describes an amusement apparatus based on a rotary capsule which holds one or two individuals and performs rotary motions.
U.S. Pat. No. 5,071,352, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Denne describes a simulator mechanism that provides 6-degrees of freedom in motion.
U.S. Pat. No. 5,182,150, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Carlos et al. describes a flight simulator utilizing a sphere assembly mounted on a pedestal. The sphere and pedestal are both moveable under the control of motion actuation.
U.S. Pat. No. 5,192,247, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Barr et al. describes a ride attraction which provides motion for a number of vehicles within a large stationary domed projection screen.
U.S. Pat. No. 5,199,875, which is hereby incorporated by reference in its entirety for the material that is disclosed therein, to Trumbull describes a method for generating supplemental motion in simulator.
SUMMARY OF THE INVENTION
It is an object of this invention to provide an apparatus for the simulation of motion sensations to passengers. This invention achieves this object by using a motion support structure, attached to each end of a passenger-holding capsule, which is capable of inducing on the capsule motion forces moving the capsule forward and backward, laterally (side by side), up and down, and/or rotationally about both the length of the capsule and about the center of the capsule. This invention accomplishes control of the motion by control parameters being processed by an external processor.
It is an object of this invention to provide a motion simulator apparatus capable of full 360 degree rotations. It achieves this object through the innovative use of a central axis assembly connected to the motion support structure.
It is an object of this invention to provide a motion simulator apparatus which is easily transportable and requires little special expertise or effort to set-up and operate. It accomplishes this object by being generally self contained and by being designed to fit within the size constraints of commercial transportation.
It is an object of this invention to provide a motion simulator apparatus which can be used as an integral component in a complete entertainment simulator package, including film or video, display, sound and motion.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a side view of the simulator invention.
FIG. 2 depicts a top view of the simulator invention.
FIG. 3 depicts an end view of the simulator invention.
FIG. 4 depicts the passenger-holding capsule positioned on an x-y-z coordinate system to show the motions described as horizontal (H), vertical (V), rotational (R), and lateral one (L1).
FIG. 5 depicts the passenger-holding capsule positioned in the x-z plane of an x-y-z coordinate system to show the motion described as pivotal (P).
FIG. 6 depicts the passenger-holding capsule positioned in the x-z plane of an x-y-z coordinate system to show the motion described as lateral two (L2).
FIG. 7 depicts the system block diagram of the simulator invention.
FIG. 8 depicts a view of the horizontal ball screw drive mechanism.
FIG. 9 depicts a view of the vertical ball screw drive mechanism and of the rotational flywheel drive mechanism.
DETAILED DESCRIPTION OF THE INVENTION
This invention is a simulator system for use in providing motion sensations or cues to passengers as a part of a total sensory environment. Motion sensations or cues are defined as the sensory response in the human user to the feelings of motion, orientation, velocity and acceleration. The primary use for this invention is in entertainment, or ride, applications. However, other uses for this invention which should be included but not limited to include education, training and research. The preferred embodiment of this invention includes a passenger-holding capsule composed of a light-weight filament wound composite material (other materials which could be used include: fiberglass, aluminum, thermoplastic or any other material from which a suitable capsule could be made), a support structure for the capsule, a number of tracks along which the capsule moves, a number of actuators to provide force to the capsule or its support structure, and a control system to coordinate, manage and monitor the simulator operation.
FIG. 1 shows the side view of the simulator invention, positioned in an imaginary x-y plane 115. The passenger-holding capsule 101 is shown suspended by a pair of spindles 104a and 104b and a pair of vertical supports 103a and 103b above a set of tracks, horizontal track 111, lateral track 112, single ended lateral track 113 and pivotal track 114. Along these tracks horizontal motion 260, lateral motion 250, single ended lateral motion 270 and pivotal motion 280 can occur. The types of motion created on these tracks are more particularly described in FIGS. 4, 5 and 6. Entrance and exit from the passenger-holding capsule 101 is provided via a series of doors 102 in each side of the capsule. Vertical motion of capsule 101 (either up or down) is indicated by an arrow 150 on FIG. 1. This vertical motion is enabled by activation of the vertical motor 201 turning the vertical belt 314 which is attached to the vertical ball screw 313 thereby applying vertical force to the cross piece of the support structure 315 which is attached to the spindle 104. The weight of the assembly is counterbalanced by pneumatic cylinders 107 contained within the vertical supports 103a and c. Rotational motion, shown in FIG. 1 by curved arrows 160 and 170, is enabled by use of the rotational motor 105 moving a drive belt 303 which in turn applies torque to a flywheel 106. The flywheel 106 transfers the torque through a rotational bearing 108 to the spindle 104 and from there to the passenger-holding capsule 101. Note that in this manner rotation can be continued indefinitely. Horizontal motion, shown in FIG. 2 by an arrow 260, is accomplished by activating horizontal motor 302 turning horizontal belt 312 which is attached to the horizontal ball screw 311 which in turn is connected to the under section of the support structure 103. Horizontal wheels 110 are also attached to the under section of the support structure 103. These wheels 110 ride on a horizontal track 111. In the preferred embodiment horizontal track 111 is of very limited length, short enough to fit within the limits of a standard cargo truck. This horizontal track 111 is designed to provide the means by which forward and backward motion is accomplished. Similarly, the lateral motion is accomplished by activating a set of linear motors 307a and 307b, one of which is positioned each side of the passenger-holding capsule 101. Each linear motor 307 turns a linear belt 316 which is attached to linear ball screw 317 thereby applying linear force to the support structure 103 and moving the capsule 101 side to side. Lateral wheels 304 are attached to the support structure 103 and are positioned on the lateral track 112. The lateral track 112 provides the means by which the entire passenger-holding capsule can be moved side to side. Single ended lateral motion (shown in FIG. 2 by arrow 270) is accomplished by movement of only one end of the passenger-holding capsule 101 along the second lateral track 113. This single ended lateral motion method, is also accomplished by the means of linear motors 308 which turns single ended lateral belt 318 which is attached to singled ended linear ball screw 319 thereby applying the single ended linear force to the support structure 103 and moving one end of capsule 101. Single ended lateral wheels 305 which are attached to the support structure 103 and positioned on the second lateral track 113. This single ended lateral motion provides the means for laterally shifting the front and the back of the passenger-holding capsule 101 independently. The pivotal motion (shown in FIG. 2 by an arrow 280) is driven is by linear motors 309 which turns pivot belt 320 which is attached to pivot ball screw 321 thereby applying the pivotal force to the support structure 103 and moving the capsule 101 about its center. Pivot wheels 306 which are attached to the support structure 103 and are positioned on the pivot track 114. This pivotal motion method provides the means to pivot the passenger-holding capsule 101 about its center. Each of the tracks 111, 112, 113, 114 are layered atop each other. Each of the tracks 111, 112, 113, 114 are, in the preferred embodiment, composed of a metal structure of two joined track structures. The preferred embodiment of the invention is configurable, enabling the combination of one or more of the motion means as necessary to simulate the required motion.
FIG. 2 shows a top view, in an imaginary x-z plane 210, of the simulator invention. In this view the passenger-holding capsule 101 is shown centered between each of the sets of tracks 111, 112, 113, 114 and in an upright position. The vertical motors 210 are shown connected to the vertical supports 103 to provide the necessary lift or release to the vertical motion.
FIG. 3 shows an end view of the simulator invention. In this view the stacking of the motion tracks 111, 112, 113, 114 is shown. The linear motor 302 which drive the linear belt 312 which turns the linear ball screw 311 is shown. This drive mechanism used to transfer power from the linear motors 302 to the support structure 103. Linear wheels are 304 are shown riding on the linear track 112. The rotational motor 105 is shown connecting to the drive belt 303 which is in turn connected to the flywheel 106 which is in turn connected to the rotational bearings 108 which is in turn connected to the spindle 104 and which is connected to the passenger-holding capsule 101. In this manner the rotational motor 105 applies force turning the passenger-holding capsule. Complete rotations are possible in either direction upon command to the rotational motor 105.
FIG. 4 is a representation of the passenger-holding capsule 101 in three-space. X, Y, and Z represent the axis defining the three-space as shown in the figure. Vertical motion is shown as motion along or in parallel to the Y axis. Horizontal motion is shown as motion along or in parallel to the X axis. Linear motion is shown as motion along or in parallel to the Z axis. Rotational motion is shown as motion around an imaginary vector running through the center of the passenger-holding capsule 101 in either direction.
FIG. 5 is a representation of the passenger-holding capsule 101 in the X-Z plane. Pivotal motion is show as motion rotating end-for-end about an imaginary center point in the passenger-holding capsule 101.
FIG. 6 is a representation of the passenger-holding capsule 101 in the X-Z plane. Single-ended lateral motion is shown as a rotation about an imaginary point in the center of either end of the passenger-holding capsule 101.
FIG. 7 shows the block diagram of the system implementation of the simulator invention. A computer system 701 controls the operation of the simulator invention by performing a process of monitoring the position of the passenger-holding capsule 101 and applying control inputs to the motor controllers 705 which in turn activate the linear motors 302 thereby, adjusting the position of the passenger-holding capsule 101. The computer system 701 in the preferred embodiment is defined as a stand-alone processor with random access memory, hard disk permanent storage, a monitor, keyboard and mouse for user interface devices, and a modem for connection to remote computer systems for the purpose of transferring new simulation environment processes. Power is supplied to all components of the system through the use of a power generator 704. In the preferred embodiment, the computer system 701 also activates and controls a laser disk based video system 702, a audio system 703 and various safety devices, such as the entrances and exits 102, the weight distribution within the passenger-holding capsule 101 the fastening of user seat-belts, the monitor of fire/smoke alarms and air conditioning, as well as control and communication with a smart terminal 707 which is installed inside the passenger-holding capsule 101. All electronic communication to and from the interior of the passenger-holding capsule 101 pass through a commutator 706, which is designed to permit continuous connectivity between the interior and the exterior of the passenger-holding capsule without regard to the rotational state or movement of the capsule.
FIG. 8 further shows the ball screw mechanism as applied to horizontal movement. The horizontal motor 302 turns the horizontal belt 312, thereby turning the horizontal ball screw 311 and driving the support structure 103 along the horizontal tracks 111. Horizontal wheels 110 are used to reduce friction between the support structure 103 and the tracks 111. Lateral, single ended lateral and pivotal movements are accomplished in an identical manner with the only significant difference being that the track is positioned at a 90 degree angle from the horizontal track 111 for the lateral track 112 and the track is curved as shown in FIG. 2 for the single ended lateral track 113 and for the pivotal track 114.
FIG. 9 further shows the ball screw mechanism as applied to vertical movement. The vertical motor 201 driving the vertical belt 314, itself turning the vertical ball screw 313 which is attached to the cross piece of the support structure 901.
In the present preferred embodiment of this invention the passenger-holding capsule 101 is composed of a filament wound composite structure as is commonly understood in the filament winding structure art. The support structure 103 and the rails 111, 112, 113 and 114 are constructed of steel, formed, joined, finished and painted in accordance with standard commonly understood methods of metal work. The motors 105, 201, 302, 307, 308 and 309 are commercially available electric motors. The pneumatic cylinders and actuators 107 are also standard commercially available parts. The motor control units 705 are standard digital motor controllers. The computer system is a Pentium based microcomputer operating at 90 MHz with 32 MBytes of dynamic Random Access Memory, a 1.6 GByte hard disk, a floppy drive, a modem, monitor, keyboard and mouse. This computer system is a common commercially available system. The commutator is a commercially available component. A smart, or processor based, terminal 707 is included in the preferred embodiment of the invention. This terminal 707 is also a common commercially available computer interface.
The preferred control logic for managing the operation of the invention has been encoded into a computer program. This computer program runs on the computer system 701. Attached herein is the source code of the computer program which is an enabling example of the control process. This computer program serves to illustrate one way in which the method of the present control process can be implemented. It should be recognized that the process and the method of the present invention are not intended to be limited by the program listing included herein. This process could be implemented using virtually any other language.
It is to be understood that the above described embodiments are merely illustrative of numerous and varied other embodiments which may constitute applications of the principles of the invention. Such other embodiments may be readily devised by those skilled in the art without departing from the spirit or scope of this invention and it is our intent that they be deemed within the scope of our invention. ##SPC1## | A motion simulator having a people-holding capsule attached at the front end and at the rear end to a supporting structure. The supporting structure has movable arms that, when extended or retracted, provide positive and negative pitch to the capsule. The supporting structure also provides the mechanism for rotating the capsule up to and in excess of 360 degrees. It is also possible to make the support structure capable of supporting forward/backward as well as side-by-side motion. With a video display system installed inside the capsule providing optical cues, this invention provides the motion cues necessary to provide a safe entertainment environment for passengers. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to means for manipulating a drafting roller carrier of a textile machine.
The drafting apparatus of a drafting frame or a roving frame or other similar textile processing machines, typically includes a plurality of associated pairs of rollers, each roller pair having an upper roller and a lower roller. The lower rollers are usually mounted on the frame and the upper rollers are mounted on a carrier generally pivotally mounted at one end on a pivot shaft for pivoting between an operating position in which the upper rollers are cooperatively disposed with respect to their associated lower rollers to form nips therebetween for the feed of the textile material through the nips and a raised or non-operating position in which the upper rollers are supported at a spacing upwardly from their respective associated lower rollers.
To releasably maintain the carrier in its operating position, the drafting apparatus typically includes a force-applying handle extending over the top of the carrier and engaging the carrier to apply a downward roller nip pressure. To move the carrier to its non-operating or raised position, the force-applying handle is manipulated to a raised position and the carrier is interconnected to the handle so that raising of the handle effects raising of the carrier. This is disclosed, for example, in German Patent 1 233 755 in which the apparatus is configured such that an operator can with one manipulation raise both the handle and the carrier from their operating positions to raised positions in which the handle and the carrier are releasably maintained. However, the handle is maintained in the raised position by a spring latch engaging a latch pin, which requires disengagement of the pin from the spring latch before the handle and carrier can be lowered to their operating positions. Thus, an involved manipulation is necessary to lower the handle and carrier.
However, the need exists for means which manipulates the handle and associated drafting roller carrier between their respective operating and non-operating or raised positions in a simple, efficient and reliable manner.
SUMMARY OF THE INVENTION
The present invention provides means for moving the force-applying handle and its associated drafting roller carrier of a textile machine between their respective operating and non-operating or raised positions simply, efficiently and reliably.
Briefly described, the present invention provides means for manipulating the carrier of a textile machine of the type having a frame and a drafting apparatus, the drafting apparatus having a plurality of lower drafting rollers and a plurality of upper drafting rollers forming a plurality of nip locations with the lower drafting rollers, the upper drafting rollers being rotatably supported on the carrier which is pivotally mounted to the frame of the textile machine and pivotable in a release direction from an operating position in which the upper drafting rollers are in nip engagement with the lower drafting rollers to a raised position in which the upper drafting rollers are out of nip engagement for servicing of the drafting apparatus and pivotable in a closing direction from the raised position to the operating position. The means for manipulating the carrier include a handle normally engaging the carrier in a handle operating position to maintain the upper drafting rollers in nip engagement with the lower drafting rollers, the handle being manipulable between its operating position and a raised position, means interconnecting the handle and the carrier for selected coordinated movement of the carrier and the handle upon manipulation of the handle between the handle operating position and a raised position, operating stop means and raised position stop means.
The operating stop means, connected to the frame, is for engagement by the handle when the handle is in the handle operating position to prevent pivoting of the carrier in the release direction. The raised position stop means, connected to the frame, is for engagement by the handle when the handle is in its raised position to prevent pivoting of the carrier in the closing direction. The interconnecting means includes means permitting manipulation of the handle away from the raised position stop means and maintaining the handle out of engagement with the raised position stop means upon manipulation of the handle from the raised position to the operation position.
In the preferred embodiment, the operating stop means includes a concave surface, the raised position stop means includes a concave surface and the handle includes a member compatibly configured to nest within the concave surface of the operating stop means when the handle is in the handle operating position for resisting relative movement between the handle and the frame to prevent movement of the carrier from its operating position, and to nest within the concave surface of the raised position stop means when the handle is in the handle raised position for resisting relative movement between the handle and the frame when the handle is in its raised position to prevent of the carrier from its raised position. The interconnecting means includes linkage means, connected to the frame and the handle, for confining movement of the handle along a predetermined travel path between its operating and raised positions, the linkage means including slot means pivotally connected to the frame and having a slot, the member being movably received within the slot.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view, in partial section, of a textile drafting apparatus which incorporates the preferred embodiment of the manipulating means of the present invention, showing the carrier and handle of the textile drafting apparatus in their respective operating positions;
FIG. 2 is a vertical sectional view, taken along lines II--II, of FIG. 1;
FIG. 3 is a side elevational view, in partial section, of the textile drafting apparatus shown in FIG. 1, showing the handle of the textile drafting apparatus in its position immediately after the handle has cleared the operating stop means of the textile drafting apparatus;
FIG. 4 is a side elevational view, in partial section, of the textile drafting apparatus shown in FIG. 1, showing the position of the handle and the carrier of the textile drafting apparatus shortly after the carrier has begun movement from its operating position to its raised position; and
FIG. 5 is a side elevational view, in partial section, of the textile drafting apparatus shown in FIG. 1, showing the carrier and handle in their respective raised positions with the handle in releasable engagement with the raised position stop means of the textile machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIGS. 1-5, a textile drafting apparatus of a textile machine is illustrated which incorporates the preferred embodiment of the carrier manipulating apparatus of the present invention. The textile drafting apparatus is of the type for drafting a strand of textile material such as, for example, roving or yarn, and includes a conventional carrier 14 pivotally mounted on a shaft 13 extending along the length of the textile machine for pivoting of the carrier 14 generally transverse to the direction of travel of the textile material through the drafting apparatus.
The carrier 14 includes an elongate portion 26 having a generally flat top surface and an end mounting portion. A plurality of upper drafting rollers 10,11 and 12 are each adjustably fixedly supported on the elongate portion 26 by conventional brackets and the upper drafting rollers 10-12 each cooperate with a respective one of a plurality of lower drafting rollers (not shown) to define therebetween a roller nip through which the textile strand travels during the drafting operation.
The textile drafting apparatus also includes a handle 15 pivotally connected by a pivot pin 23 to the end mounting portion 25 of the carrier 14 for pivoting about an axis parallel to the shaft 13. The handle 15 includes an end portion 29 through which the pivot pin 23 is rotatably mounted, a free end portion 30 and an interconnecting portion 28 interconnecting the end portion 29 and the free end portion 30. The free end portion 30 includes a conventional handle grip for convenient engagement of the handle 15 by an operator. The handle 15 is mounted generally centrally laterally over the top of the carrier 14 and the end portion 29 is received in a vertical slot 24 formed on the carrier 14 rearwardly of the elongate portion 26 thereof. The handle 15 additionally includes a planar force applying surface 31 adapted to engage the generally flat top surface of the elongate portion 26 of the carrier 14 to apply a downward roller nip force through the carrier 14 to the upper rollers 10-12. The handle 15 can be formed in conventional manner from plate steel.
As best seen in FIG. 2, the handle 15 includes a cylindrical pin 19 extending laterally to each side of the handle. A pair of hollow cylindrical spacers 32 are each rotatably mounted on a respective lateral side of the cylindrical pin 19. A pair of identical stop plates 16 are connected to one another in spaced, parallel relation by a transverse bolt 27, shown in FIG. 1, and are adjustably fixedly mounted to the shaft 13 by a pair of stop bolt assemblies 33,34. The stop bolt assembly 33 includes a bolt threadably mounted to a plate which extends transversely between the stop plate 16 and is fixedly connected thereto. The stop bolt assembly 34 includes a bolt threadably mounted to the stop plates 16. As seen in FIG. 1, the adjustment bolt of the stop bolt assembly 33 engages an axially extending recess in the shaft 13 and the bolt of the stop bolt assembly 34 engages the shaft 13 at a location circumferentially spaced from the axially extending shaft recess to adjustably fixedly mount the stop plates 16 to the shaft 13.
A linkage means includes a slot plate 17 pivotally connected by a pivot pin 21 to one of the stop plates 16 and having a slot 22 extending radially with respect to the axis of the pivot pin 21. The transverse dimension of the slot 22 is slightly greater than the diameter of the pin 19 but of a smaller extent than the outer diameter of the spacers 32. The slot plate 17 is disposed between one of the spacers 32 and the rear portion 29 of the handle 15 and the pin 19 is rotatably received within the slot 22.
The stop plates 16 form an operating stop means and a raised position stop means. The operating stop means includes an upwardly facing concave surface 20 inclined downwardly and forwardly with respect to the direction of feed of the yarn through the roller nips. The raised position stop means includes a downwardly facing concave surface 18 inclined downwardly and forwardly with respect to the direction of travel of yarn through the roller nips and spaced rearwardly and downwardly from the concave surface 20 of the operating stop means with the pivot pin 21 mounted between the concave surfaces 18,20.
The concave surface 20 of the operating stop means projects behind the pin 19 in the path of pivoting of the pin 19 about the shaft 13 when the handle is at rest on the carrier so that any attempted raising of the carrier without positive manipulation of the handle would be prevented by the surface obstructing movement of the pin 19; but the inclination of the extent of the surface 20 is limited so as not to interfere with pivoting of the pin 19 about the pivot connection pin 23 when the handle itself is manipulated upwardly.
Similarly, the concave surface 18 of the raised position stop means projects in front of and over the pin 19 in the path of pivoting of the pin 19 about the shaft 13 when the handle and carrier are in their raised positions so that the handle and carrier will be maintained in their raised positions; but the inclination of the extent of this surface 28 is sufficient to not interfere with rearward pivoting of the pin 19 about the pivot connection pin 23 when the handle is manipulated rearwardly from its raised position to disengage the pin 19 from the surface so that the handle and carrier can be lowered to their operating positions.
The aforementioned slot plate 17 and pin 21 connection interconnects the handle and carrier so that manipulating of the handle can effect, through the pin 19 and slot plate 17, manipulation of the carrier, with the slot 22 providing sufficient lost motion in the connection to permit disengagement of the pin 19 from the stop surfaces 18,20 before the carrier is manipulated and to guide the pin 19 around the stop plate 16 from surface to surface as the handle is manipulated between its operating and raised positions.
The operation of the carrier 14 and the handle 15 is as follows. As seen in FIG. 1, the carrier 14 is positionable in an operating position in which the upper drafting rollers 10-12 are in nip engagement with the lower drafting rollers. The handle 15 is in an operating position in which the force applying surface 31 is in contact with the top surface of the carrier 14 and the intermediate portion 28 of the handle 15 extends generally longitudinally over the center of the carrier 14. In the operating position of the handle 15, the pin 19 is in engagement with the concave surface 20 of the operating stop means with the surface resisting movement of the pin 19 and thereby obstructing pivoting of the carrier 14 about the shaft 13. As seen in FIG. 1, the axes of the pin 19, the pivot pin 21 and the pivot pin 23 generally lie in a common plane.
When an operator desires to perform a servicing operation on the drafting apparatus, or otherwise wishes to raise the carrier, the operator engages the grip of the handle 15 and manipulates the handle 15 to pivot about the pivot pin 23 in a clockwise direction as viewed in FIG. 1. The pivoting movement of the handle 15 moves the force applying surface 31 of the handle out of contact with the top surface of the carrier 14 as the rear portion 29 of the handle 15 moves relative to the slot 24 of the carrier 14. As seen in FIG. 3, the slot 22 permits the pin 19 to move radially outwardly along the slot 22 with respect to the axis of the pivot pin 21 to permit the pin 19 to clear the surface 20 of the operating stop means. Once the pin 19 has moved fully radially outwardly along the slot 22, the slot plate 17 constrains the pin 19 to move along a travel path within an arcuate band, concentric with respect to the pivot pin 21 and having a radial dimension defined by the length of the slot 22, during further movement of the handle 15 in a clockwise direction about the pivot pin 23.
As seen in FIG. 4, continued clockwise movement of the handle 15 about the pivot pin 23 after the pin 19 has moved fully radially outwardly along the slot 22 produces coordinated movement of the carrier 14 with the handle 15 toward the raised positions. Specifically, as seen in FIG. 4, the carrier 14 pivots in a clockwise direction about the shaft 13 due to the force applied by the handle 15 against the pivot pin 23. Eventually, the coordinated movement of the handle 15 and carrier 14 results in a relative disposition between the carrier 14 and the stop plates 16 such that the spacing of the pivot pin 23 and the pivot pin 21 is sufficient to permit movement of the pin 19 therebetween, through manipulation of the handle 15, into engagement with the surface 18 of the raised position stop means. In this regard, the handle 15 is manipulated to cause the pin 19 to move radially inwardly along the slot 22 toward the pivot pin 21 and the handle is manipulated such that the force applying surface 31 is brought into engagement with the top surface of the carrier 14, which is now in a raised position in which the upper drafting rollers 10-12 are spaced out of nip engagement with the lower drafting rollers.
The surface 18 of the raised position stop means is dimensioned with respect to the pin 19 and the pivot pins 21,23, when the force applying surface 31 of the handle 15 is in engagement with the top surface of the carrier 14 so that the pin 19 will be prevented from moving out of engagement with the surface 18 when the handle is not manipulated from its raised position.
In this regard, the weight of the carrier 14 produces a counterclockwise pivoting of the carrier 14 about the shaft 13 which causes the pivot pin 23 to apply an upwardly directed force to the rear portion 29 of the handle 15 which results in the pin 19 being urged against the surface 18 of the raised position stop means. Accordingly, the carrier 14 and the handle 15 are maintained in their respective raised positions once the handle has been manipulated to bring the pivot pin 19 into raised stop means engagement.
To move the carrier 14 and the handle 15 from their respective raised positions, the handle 15 is manipulated to move the pin 19 out of engagement with the surface 18 of the raised position stop means. In this regard, the slot plate 17 pivots about the pivot pin 21 to guide the pin 19 out of engagement with the surface 18 during initial movement of the pin 19 from its surface engaging position. During this initial movement of the pin 19, the pin moves radially outwardly along the slot 22 with respect to the pivot pin 21 and the slot plate 17 guides the pin along a travel path concentric with respect to the pivot pin 21. This movement of the handle 15 allows the carrier 14 to pivot downwardly, constrained by the pin 19 and slot 22 connection, in coordination with downward manipulation of the handle until the carrier 14 is returned into its operating position in which the upper drafting rollers 10-12 are in nip engagement with the lower drafting rollers. The operator then continues to manipulate the handle 15 to its operating position, during which movement the pin 19 is moved into engagement with the surface 20 of the operating stop mean to maintain the carrier 14 in its operating position.
It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of a broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. | An apparatus for manipulating the drafting roller carrier of a textile machine includes a handle for selectively maintaining the drafting roller carrier in an operative position in which the upper drafting rollers on the carrier are in nip engagement with the lower drafting rollers. The apparatus additionally includes an assembly for interconnecting the handle and the carrier for selected coordinated movement of the carrier and the handle upon manipulation of the handle between a handle operating position and a raised position. An operating stop device and a raised position stop device each include a concave surface and the handle includes a nesting member compatibly configured with the concave surfces to nest therein to prevent movement of the carrier from its respective operating or raised position. The nesting member is movably received in the slot of a slot device pivotally connected to the frame for constraining the nesting member to move along a predetermined travel path during manipulation of the handle between its operating and raised positions. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to the microbial decontamination and medical equipment maintenance arts. It finds particular application in conjunction with counting a number of strong oxidant sterilization cycles to which medical (including dental and surgical) equipment has been subjected and will be described with particular reference thereto. However, it is to be appreciated that the invention will also find application in conjunction with monitoring the number of times that mortuary, laboratory, and other equipment have been sterilized or disinfected, monitoring other processing cycles of both medical and non-medical equipment, and the like.
Sterilizing or disinfecting equipment subjects articles to an environment which kills microbes. Common sterilizers include a steam autoclave which subjects the items to a combination of high temperature and pressure. Ethylene oxide gas sterilizers subject the items to reactive, ethylene oxide gas. Liquid sterilizers treat the items with a liquid solution that includes a reactive component, such as a strong oxidant.
Not all regularly sterilized medical instruments are made of materials which are substantially immune to the high temperature and pressure of a steam autoclave. Many instruments have plastic or rubber components which cannot withstand the thermal and pressure stresses of a steam autoclave. These items are typically sterilized using low temperature fluid (gas or liquid) sterilization systems.
Many instruments are rated to have a limited useful life. One scale for measuring the useful life is the number of sterilization cycles. After a preselected number of sterilization cycles, the instrument no longer has an assured functionality and should be discarded or rebuilt.
The loss of assured functionality may be attributable to various causes including dulling of cutting edges, potential misalignment of parts or wobble in joints, degradation of parts, particularly plastic and rubber parts, from use or the microbial decontamination processing or the like. The high temperatures of steam sterilization or reaction with gas or liquid sterilants may degrade some plastic and rubber parts. Such plastic and rubber components may cumulatively become bleached, brittle, or tacky.
Heretofore, difficulty was encountered in determining whether the functionality of the instruments was compromised. Degradation of internal parts is not readily determined by visual observation. Some degradation, such as becoming brittle or dull is hard for a human observer to gauge. Various techniques have been tried, but each has significant drawbacks. Periodic disassembly is time consuming and is not available for all instruments. Counting the number of use/sterilization cycles is often unreliable, particularly when there are multiple users and multiple copies of each instrument. Inventory control and purchase date monitoring does not provide a reliable indication of the number of use and sterilization cycles.
The present invention provides a new and improved technique for monitoring the number of use/sterilization cycles to which an instrument is subjected.
SUMMARY OF THE INVENTION
In accordance with the present invention, a method of indicating a sterilization life-span of an instrument is provided. A color coded marker is connected with the instrument. The color coded marker has a composition which is acted upon by the reactive component of fluid sterilants to change color. The color composition is formulated such that the color change occurs over a preselected number of cycles, which number of cycles are preselected in accordance with the requirements of the instrument.
In accordance with a more limited aspect of the present invention, a warning or caution label is provided in conjunction with the color change material such that the warning label becomes apparent within the preselected number of cycles.
In accordance with a more limited aspect of the present invention, the color change element is an integral portion of the instrument.
In accordance with another more limited aspect of the present invention, the sterilization fluid is a liquid solution containing a strong oxidant. The color change material includes a member which is impregnated with a pigment which changes color as it is oxidized.
In accordance with another more limited aspect of the present invention, a means is provided for controlling access of the sterilant solution to the color change composition.
One advantage of the present invention is that it provides an instrument carried indicator of remaining life-span of the instrument.
Another advantage of the present invention is that the indicator is updated or indexed without operator intervention.
Another advantage of the present invention is that it provides a ready indicator that the functionality of the instrument has not been compromised by over-use.
Other advantages of the present invention include its low cost and simplicity of use.
Still further advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating a preferred embodiment and are not to be construed as limiting the invention.
FIG. 1 is an exploded view of a tag in accordance with the present invention for attachment with an instrument;
FIG. 2 is a diagrammatic illustration of color intensity versus number of cycles for one preferred embodiment of a color change composition of the present invention;
FIG. 3 is a diagrammatic illustration of color intensity versus number of cycles for another embodiment of the present invention;
FIG. 4 illustrates a life-span color indicator in accordance with the present invention integrally connected with an instrument;
FIG. 5 is an exploded view illustrating an exemplary construction of the color indicator of FIG. 4; and,
FIG. 6 illustrates an alternate embodiment of a color coded life-span indicator.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 1, a label 10 carries an indicia 12 indicating that the associated instrument is to be reconditioned or discarded. Preferably, the label 10 is of an oxidation resistant material such as a thin film plastic. In the illustrated embodiment, the indicia 12 is a printed word indicating that it is time to recondition or discard the associated instrument. Preferably the word is printed with a pigment that is highly resistant to oxidation or, sealed against contact with oxidants. However, graphic symbols and other indicia are also contemplated.
The label 10 is laminated between two layers of pigment impregnated plastic 14. The layers are impregnated with a pigment material which changes color or opacity with exposure to a sterilization or other microbial decontamination fluid. An affixing means such as a plastic strap 16 is provided for affixing the tag to the associated instrument. Preferably, the strap has a slide clasp 18 with a one-way mechanism inside such that once the strap is tightened to the instrument, it cannot be removed without cutting the strap or destroying the strap or slide clasp.
The plastic layers 14 are constructed of a translucent material, such as polyvinylchloride (PVC), silicon rubber, or the like. The material is colored with a dye or pigment that changes color with exposure to the microbial decontamination fluid. In the preferred embodiment, the instrument is sterilized in an automated processor such as the one illustrated in U.S. Pat. Nos. 4,892,706 or 5,217,698. The microbial decontamination fluid is a liquid solution containing a strong oxidant, specifically peracetic acid. However, other liquid and gaseous fluids are also contemplated, including hypochlorite solutions, ethylene oxide gas, and the like.
The pigment may be any of various dyes, chromogens, and the like which change color as the result of exposure to a preselected time-concentration exposure of the sterilant or disinfectant fluid. Typically, organic pigments fade or lose their color with exposure to strong oxidants. Thus, as the pigment is exposed to the liquid or gas or to high temperature steam, the pigment fades allowing the warning indicia 12 on the label 10 to be read.
In one preferred embodiment, the polyvinylchloride layers 14 were immersed in a circulated dyeing solution. The dyeing solution is prepared by dissolving 105 mg of crystal violet in 100.0 ml of anhydrous ethanol. 15 g of ethylcellulose is dissolved in 400.0 ml of toluene. 25 ml of the crystal violet solution are mixed with 400 ml of the ethylcellulose solution and the mixture circulated over the polyvinylchloride strips for 42 minutes at ambient temperature. Excess dye is removed and the plastic strips dried. Thereafter, the plastic strips are baked at 37° C. in an incubator for 2 hours.
In addition to crystal violet and derivatives of pararosaniline other pigments, stains, dyes, chromogens, tinting agents and chemistries that upon reaction produce color changes may be used. These include certain food dyes, biological stains as phenazone based dyes such as safranine, and stains such as used in acid-base indicators.
With reference to FIG. 2, for calibration and testing, the impregnated polyvinylchloride plastic material was subject to a multiplicity of 12 minute sterilization cycles with the above-referenced automated processor. In each cycle, the tag was immersed in a peracetic acid solution having an initial peracetic acid concentration of about 2000 ppm and a pH of about 6.5. The above described impregnated material showed little color change until after 40 sterilization cycles. By 95 cycles, the color was substantially gone.
Shorter use cycle indicators can also be designed. For example, 25 ml of the crystal violet/anhydrous ethanol solution is mixed with 400 ml of anhydrous ethanol. The tag is immersed in circulating solution for 5 minutes and dried. As illustrated in FIG. 3, the tinted plastic material started to show noticeable coloring change after only 7 cycles. By the end of 9 cycles, the plastic material completely lost its color.
Other pigments and solutions may be utilized. Similarly different baking durations and temperatures can be utilized to set the dye more or less strongly, hence to extend or shorten the number of cycles before the color is substantially lost. Other solution concentrations and soaking times are also contemplated. Extending the immersion duration or increasing the concentration tends to increase the number of cycles. Diluting the concentration and reducing the soaking time shortens the number of cycles.
In another embodiment, a 0.2% indicating dye solution was prepared by dissolving 2.0 g of crystal violet into 1.0 liter of tap water. This solution was mixed until completely dissolved and homogeneous. Porex brand porous open cell plastic foam plugs were then placed into test tubes, each containing approximately 10 ml of the dye solution. Inasmuch as the density of the plugs is less than that of the dye solution, two bath balls were added to each of the tubes to insure that the plugs remained completely submerged in the solution during the dying process. The test tubes were then placed into a test tube rack which was then placed into a vacuum desiccator. The vacuum pump was switched on and allowed to pull a vacuum in the desiccator for 20 minutes, following which the desiccator valve was closed to retain the vacuum after the vacuum pump was switched off. The plugs were then allowed to soak in the dye solution, under vacuum, for 2 hours, following which the vacuum on the desiccator was released. The plugs were then allowed to remain in the dye solution an additional 5 minutes before being removed from the dye. All transferring of the plugs was accomplished by means of forceps to insure that neither any dye was removed from the surface, nor was any finger oil, which might affect the uniformity of dye penetration, added to the surface of the plugs. The plugs were then placed into clean test tubes and dried in an incubator at 56° C. for approximately 3 hours.
Sixteen of the dyed plugs each attached to a vacustat clip to prevent them from floating in the sterilant, were then evenly dispersed on the fixation rack for the rigid tray. The fixation rack was then placed into a rigid container along with a commercial chemical indicator strip, also attached to a vacustat clip. The container was then placed within the processor tray and a peracetic acid sterilization cycle run. Following the cycle, the chemical indicator strip was removed and inspected for cycle completeness by comparing its color to the end point color block on the chemical indicator bottle. Four of the Porex plugs on the rack were chosen at random and removed from the container, with the remaining 12 plugs left undisturbed. A new chemical monitor strip, with a vacustat clip, was then placed into the container; a new cup of sterilant was added to the processor and a second processor cycle was initiated. While the second cycle was running in the processor, the four plugs which had just been removed from the processor, were sliced in half by means of a scalpel and forceps. The color of the internal surfaces of the plugs was compared to that of the outer surfaces. Both the outer surfaces and the inner, cut surfaces were inspected for degree and uniformity of dye penetration then their color was compared to the Fuller O'Brien Color Chip Chart for a color match. This procedure was repeated until all sixteen plugs had been removed from the sterilization processor, four per cycle, and inspected. At that point, four of the eight plugs which had not been exposed to sterilant in the processor were placed into the same processor in the same manner, but were exposed to a cycle in which no peracetic acid was used, solely builder. These four plugs represent a control for the possibility that rather than being bleached by the sterilant, the dye was washing out of the plugs by the action of the detergents or other components of the sterilant solution.
The results of the exposure of dyed Porex media plugs to peracetic acid sterilant processing is set forth in Table 1. Those plugs exposed to only one cycle with sterilant exhibited a uniform color on the outer surface. There was a discernible difference in color between those plugs exposed to one processor cycle with sterilant and the unprocessed controls which were dyed but which saw no exposure to either peracetic acid or builder. The same is true of those plugs exposed to two cycles with sterilant. The four plugs which were exposed to three processor cycles in the presence of peracetic acid sterilant exhibited a very faint, but nonetheless, detectable color on the outer surface. The inner surfaces, however, appeared uniform in color, and were the same color as the outer surface. Those plugs exposed to four cycles with sterilant were completely bleached on the outer surface. They appeared identical to the untreated plugs which had never been exposed to crystal violet dye. The inner surfaces of the four-cycle plugs were identical to the outer surface, i.e. completely bleached. In addition, these four plugs which had been exposed to the four sterilant cycles were lighter than any of the Fuller O'Brien color chips.
The color of the outer surfaces of the processor control plugs, which were exposed to one processor cycle in the presence of builder but not peracetic acid, did not match any of the Fuller O'Brien color chips. They were slightly lighter than the start block on the bottle label. When compared to the unprocessed plugs, dyed but not processed, which were the color of the start block on the bottle label, the inner surfaces of the builder-only control plugs did not exhibit uniform color, and their outer surfaces were also lighter in color, however, they were significantly darker purple than any of the plugs which had been processed with the peracetic acid sterilant.
TABLE 1______________________________________POROUS MEDIA LIFE-SPAN INDICATORCYCLE COUNT - COLOR CORRELATION FULLERCUMUL. O'BRIENCYCLES COLOR______________________________________0 *1 3-D54 1-D552 4-D1153 4-D1114 **______________________________________ * These dyed control plugs were exposed only to builders (no peracetic acid) in the processor. They are just perceptibly lighter than the unprocessed plugs. ** All four plugs were bleached white. Their white color was identical t that of the untreated factory plugs.
Thus, porous media can be successfully utilized as a cycle counter in the presence of peracetic acid based sterilant. Crystal violet dye applied to a porous media material will bleach to a degree dependent on the amount of dye present on the surfaces of the material, the concentration of peracetic acid in the sterilant, the flow rate of the sterilant, and the accumulated time of exposure to the sterilant. Inasmuch as the mean concentration of peracetic acid sterilant and its flow rate tend not to vary much from processor to processor and from cycle to cycle, a given amount of dye remaining within the porous media should be indicative of the number of cycles to which that cycle indicator has been exposed, this being a function of the accumulated exposure time of the dye to sterilant.
As another alternative, multiple layers can be added. For example, a clear coat may be applied over the indicator of Example 2. By selecting a coating with a predictable number of cycles before it reacts, the color change of the embodiment of FIG. 2 can be delayed the corresponding number of cycles. As another alternative, layers of different pigments can be applied such that rather than just fading in monochrome, the indicator changes color as the surface layer fades and an underlying layer is retained.
Other techniques for affixing the indicator to the instrument are also contemplated. With reference to FIG. 4, a medical instrument 20 such as an endoscope includes a ring 22 of the indicator material. For example, the instrument may have two portions which are threadedly interconnected adjacent to a recessed area in which the indicator ring 22 is mounted. Alternately, the ring can be heat shrunk onto the instrument. As shown in FIG. 5, an inner label 24 includes an indicia 26 such as the word "rebuild" or "discard". The ring 22 of the translucent, impregnable material surrounds the label exposing the indicia 26 as the impregnated color fades with repeated sterilization cycles.
With reference to FIG. 6, rather than using the color change indicator to obscure an indicia, the color itself can be used as the indicator. For example, a scale 30 has a portion 32 having the initial color of the color change material, a portion 34 having an intermediate color of the color change indicator, and a color indicator portion 36 denoting the color of the indicator 22 which indicates that the instrument should be discarded or rebuilt.
Various other structures for attaching a layer of the color changing instrument life-span indicator to the instrument may also be used. For example, the indicator may be painted on or coat a portion of the instrument. A functioning portion of the instrument may be constructed of the indicator plastic material. As another option, the region of the material which is impregnated with the color change indicator can be limited to a region having a preselected shape, such as the word "discard". The remainder of the material may be colored with a similar pigment which is insensitive to the oxidant or coated to protect it from the oxidant such that as the indicator region changes color, the word "discard" or another indicia becomes visible.
The invention has been described with reference to the preferred embodiment. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | A pigment such as crystal violet is impregnated in or otherwise affixed to a translucent plastic or porous member (14, 22). The color change material changes at least one of opacity or color with repeated exposure to a fluid sterilant, such as an oxidant solution. A label (10, 24) is mounted behind the translucent plastic material and carries an indicia (12, 26). With repeated sterilizations of the instrument, the color change material becomes progressively more translucent, allowing the indicia to be read through the translucent plastic material. When the indicia becomes visible, such as after about 7 sterilization cycles in FIG. 3, the user is warned to discontinue use of the instrument, either discarding it or having it rebuilt. Rather than having a written indicia, a color scale (30) can be provided for comparison against the current color of the color change material. When the color changes to the discard color on the color scale, the user is again advised to discontinue use of or rebuild the instrument. | 0 |
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to archery. More particularly, a bracket having multiple adjustments for attaching a light or other apparatus that is pointed in the direction of the arrow and in a location for manual activation is disclosed.
[0003] 2. Description of Related Art
[0004] There are a variety of designs of bows and equipment to use with the bow in the field of archery equipment. For example, improved sights for use in archery have been developed recently, as disclosed in U.S. Pat. No. 7,328,515, which is hereby incorporated by reference. For use in hunting certain wild animals, such as hogs, lights on the bow may be used in some areas, since the animals are very destructive of the environment in those areas. Lights now available include the “Hawglite,” described at www.hawglite.com. That light is mounted on a bow and electrically connected to batteries by an electrical cord, and may be activated by a pressure-sensitive switch mounted on the grip of the bow
[0005] There is a need for a simpler apparatus that can be attached to bows to allow use of a separate portable light or other apparatus that is to be pointed in the direction that the bow is aimed. Such apparatus should allow use of different portable lights that are readily available and that can be readily interchanged on a bow.
BRIEF SUMMARY OF THE INVENTION
[0006] A bracket is provided for attaching to bows using the stabilizer hole normally present on a bow or a similar threaded hole. The bracket allows fixing a portable light that is directed in the direction of an arrow shot from the bow and is adjustable in vertical and horizontal planes and in position and distance with respect to the bow. A camera or other apparatus may be used in place of the portable light.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0007] FIG. 1 depicts a hunter using a bow and arrow and aiming at a wild hog.
[0008] FIG. 2 illustrates one form of bow that may be used with the bracket disclosed herein.
[0009] FIG. 3 is a top view of one embodiment of the bracket disclosed herein before adjustment.
[0010] FIG. 4 is a front view of one embodiment of the bracket disclosed herein before adjustment.
[0011] FIG. 5 is an elevation view of one embodiment of the bracket disclosed herein before adjustment.
[0012] FIG. 6 is a top view of one embodiment of the bracket disclosed herein after adjustment.
[0013] FIG. 7 is an elevation view of one embodiment of the bracket disclosed herein after adjustment.
[0014] FIG. 8 is a perspective view of a bow, held by a bow hand with a light held by the bracket disclosed herein being positioned for activation by a finger of the bow hand.
DETAILED DESCRIPTION OF THE INVENTION
[0015] FIG. 1 is a prospective view of bow 10 with arrow 14 being used by a hunter at night to shoot wild animal 12 . The bow contains sight 16 , which is an accessory often used on bows, and bracket 18 , disclosed herein, shown attached to the bow. Bracket 18 will have a light attached thereto when hunting at night, but may have a camera when hunting by day.
[0016] Referring to FIG. 2 , bow 20 is shown. One embodiment of bow 20 has body 21 , grip 22 , eccentrics 23 and stabilizer hole 25 . Stabilizer hole 25 may be used for a variety of accessories such as a reel, for example, when the bow is used for bow fishing. Most commonly it is used for a stabilizer, which is used to stabilize the bow when shooting. For some bows, such as a long bow, a bracket may be attached to the bow to supply support for a bracket of this invention. The bracket would be attached normally to the limb bolts. If a bow is factory made recurve, it normally has a stabilizer hole. If the bow is custom-made, a stabilizer hole will often be requested. Bracket 18 , attached in stabilizer hole 25 , is disclosed herein. Other forms of fasteners, such as clamps, may be used to attach bracket 18 to a bow. Bracket 18 , as will be fully described below, was designed to be adjustable in a horizontal and a vertical plane. Also, the location of apparatus supported by bracket 18 from and along the bow is adjustable.
[0017] Referring to FIG. 3 a top view of bracket 18 holding light or other apparatus 37 is shown. Bow thumb screw 30 is used for adjusting bolt threads 32 into the stabilizer hole of a bow. The size of these threads is standard in most bows, but the threads may be adapted for any particular bow. Although threads 32 are illustrated for fastening bracket 18 to a bow, other fasteners may be used. Bolts 34 , which may be Allen head bolts, are used to adjust the position of a device that is attached to the bow through threads 32 . Vertical plane adjustment thumb screws 35 , threaded on a shaft, may be used to move cradle 36 in a vertical plane by rotation around the shaft. Cradle 36 may have pin light or other light 37 fastened to the cradle by bands or retainers 38 , which may be rubber, plastic or metal bands. Alternatively, a threaded fastener may be used. Although penlight 37 is illustrated, other apparatus such as a movie or still camera may be used in cradle 36 . Preferably the diameter of light or apparatus 37 is less than about 2 inches, or more preferably less than about 1 inch, and an activation switch, described below, is preferably on the rear of the apparatus.
[0018] Referring to FIG. 4 , a front view of bracket 18 is shown. Cradle 36 holds light or apparatus 37 . If device 37 is a light, it may have lens 37 a which may be of various colors such as red, green, or blue, for hunting of various types of game. For example, a red lens is found to be particularly effective for wild hogs, since it does not attract the attention of hogs as much as white light. Vertical plane adjustment thumb screw 35 , attached to a horizontal shaft, may be used to aim light 37 in the preferred angle in a vertical plane. Slotted flat bar 41 may be used to hold Allen head bolts 34 , used for adjusting the vertical position of cradle 36 and the distance of cradle 36 from a bow. Alternatively, other members adjustable in length or distance from the fastener attached to a bow, such as a telescoping member, may be used. The angle of slotted flat bar 41 with respect to vertical may be selected to allow optimal placement of cradle 36 . In one embodiment, slotted flat bar 41 may be curved.
[0019] Referring to FIG. 5 , the parts described above and below are shown in an elevation view. Slotted flat bar 41 is shown as straight. In this view, horizontal plane adjustment thumb screw 51 , which is on a vertical shaft that passes through slotted bar 41 and is threaded into the support for cradle 36 , may be loosened and tightened to allow adjustment of the direction of cradle 36 in a horizontal plane. Activation switch 37 b is shown at the back of device 37 . Device 37 may be one of the widely available LED lights, such as a Streamlight “Stylist,” or a “SunLight Jr.” Activation switch 37 b is preferably a tail cap switch or pressure switch.
[0020] FIG. 6 shows the parts described above with cradle 36 adjusted in a horizontal plane. FIG. 7 shows the parts as described above with cradle 36 adjusted in the vertical plane. The adjustment in the horizontal plane is made with thumbscrew 51 and the adjustment in the vertical plane is made with thumbscrew 35 , preferably by loosening and retightening the thumbscrews. In another embodiment, cradle 36 is moved and held in a selected direction by a friction mechanism (not shown) that is formed by friction between the shaft and the shaft holder. The friction may be controlled by application of a spring force. The position of cradle 36 with respect to the bow may be adjusted by moving the flat bar, as explained above. With the multiple adjustments, it is possible to place activation switch 37 b ( FIG. 5 ) at the optimum location for manual activation, with light 37 aimed in the direction that an arrow will be shot.
[0021] FIG. 8 shows a perspective view of sight 16 on bow 21 , bow 21 being held by bow hand 80 . The position along slotted flat bar 41 has been adjusted using bolts 34 such that activation finger 82 and light 37 having switch 37 b is positioned such that switch 37 b can be activated by activation finger 82 . This may be achieved by adjusting the position of bracket 36 using bolts 34 . Light or apparatus 37 is aimed in the direction of an arrow being shot using adjustment thumb screws 35 and 51 . The position of the light on cradle 36 can be adjusted, using bands 38 such that finger 82 will be a selected distance from switch 37 b. When hunting hogs at night, switch 37 b is normally not activated until the bow hunter is ready to shoot. When the light is turned on, the hunter can shoot very quickly.
[0022] Although the present invention has been described with respect to specific details, it is not intended that such details should be regarded as limitations on the scope of the invention, except to the extent that they are included in the accompanying claims. | A bracket for on a bow used in archery is provided. The bracket includes a cradle that can support an apparatus such as a light at a location such that the light can be operated by a finger of the hand holding the bow. The cradle can be adjusted in a horizontal and vertical plane such that apparatus on the cradle is pointed in the direction that an arrow is to be shot and at the same time be easily activated. | 5 |
BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a magnetic tape cassette, such as video tape cassette or the like.
In the past, a magnetic tape cassette has been typically made from an upper case half, a lower case half, a strip of magnetic tape, a pair of reels around which the magnetic tape is wound, a tape guide at the tape reeling side, and another tape guide at the tape unreeling side. The magnetic tape extends from one reel through its associated tape guide and then through the other tape guide to its associated reel. The tape guides are tightly fitted onto guide posts so that they are not rotated by means of the travelling magnetic tape. Further, at the tape unreeling side, a tape pad and a guide post are normally provided, both of which cooperate to hold the travelling magnetic tape therebetween to prevent the tape from being loosened during travelling.
Obviously it is preferable that a magnetic tape cassette has a minimal dynamic frictional resistance so as to ensure the smooth movement of the magnetic tape. Frictional resistance increases in proportion to the number of contact locations such as the tape guides, guide pins on a video player deck, and others, as well as the total tape contact area.
It is recognized that, in a conventional magnetic tape cassette, especially in quick feed and quick return, the magnetic tape forms generally a 110 degree contact angle with the tape reeling guide and a 120 degree contact angle with the tape unreeling guide, resulting in a 230 degree total tape embracing angle. Because the tape guides are fixed to one case half without any permitted rotation thereof, the magnetic tape tends to adhere to the cylindrical surface of each tape guide when the tape starts to move from a standstill or moves in the reverse direction. This adherence results in an unexpected increase in static frictional coefficient between the magnetic tape and the tape guides. Thus sometimes the magnetic tape fails to move, e.g., when the tape deck has a reduced reeling torque.
One way of preventing the above-mentioned stopping problem is to reduce frictional resistance between the magnetic tape and the tape guides, e.g., by designing the tape guides at the reeling and unreeling sides each in the form of a rotating body. This arrangement, however, causes frictional resistance to be excessively reduced, and other problems may develop, such as forward loosening, pinching at the front cover, undesirable rolling or the like, because the magnetic tape is very free to move around the tape guides. These problems are due to the loosened part of the magnetic tape coming out of the tape guides because of the positional relation to the rotation stopper means for the reels arranged in both the case halves to the ratches on the outer periphery of the reels, when the cassette is removed from the player deck. Further, since the conventional magnetic tape cassette is constructed such that the tape pad and the guide pole located at the unreeling side serve for holding the travelling magnetic tape therebetween, there is little possibility that loosening takes place at the tape unreeling side. However, the magnetic tape is easily loosened with the additional aid of rotational movement of the tape guide at the tape reeling side, becaus there is provided no means for holding the travelling magnetic tape at this location. Therefore, if the tape guides at both the tape reeling and unreeling sides are designed each in the form of a rotational body, it is necessary that the guides themselves have some frictional resistance on their cylindrical surfaces to some extent or that another magnetic tape holding means such as a tape pad which serves for holding the travelling magnetic tape to prevent any loosening is arranged additionally at the tape reeling side. However, such remedial measures have drawbacks, such as complicated construction, increased number of parts and components, increased manufacturing cost, and others.
The subject invention is intended to obviate the above mentioned drawbacks with the conventional magnetic tape cassette, and its object is to provide an improved magnetic tape cassette which has reduced frictional resistance to the magnetic tape and at the same time has a minimized loosening of the tape, while maintaining the fundamental construction of the magnetic tape cassette as described above.
To accomplish the above mentioned object there is proposed in accordance with the present invention an improved magnetic tape cassette which is characterized in that it contains two tape guides, one at each of the tape reeling and unreeling sides, wherein just the tape guide at the tape unreeling side is designed in the form of a rotational body. The invention is particularly suitable for applications in which the magnetic tape moves at a constant travelling speed (in the recording and reproducing modes) only in one direction, as is the case with video tape cassettes. This type of magnetic tape cassette normally would not be employed when the magnetic tape moves at a constant travelling speed in both directions, unless some provision is made to permit only the tape guide at the tape unreeling side to be rotational.
The present invention will be described in more detail below.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a partially sectioned plan view of a magnetic tape cassette in accordance with the present invention.
FIG. 2 is a perspective view of the lower case half of the magnetic tape cassette of FIG. 1, shown in an enlarged scale, wherein the tape guides and guide poles are illustrated in a disassembled state.
DETAILED DESCRIPTION
As illustrated in the drawing, FIGS. 1 and 2, the cassette includes upper and lower case halves 1 and 2, magnetic tape 3, and reels 4 and 5 around which the tape is wound (during recording and reproducing, tape is reeled onto reel 4 and unwound from reel 5). Tape guides 6 and 7 supported by posts 10 and 11 fitted in holes 8 and 9 guide the tape during its movement. Tape pad 12 and guide post 13 also hold the tape 3 therebetween.
In accordance with the invention, the tape guide 7 located at the tape unreeling side and positioned adjacent the front edge of the cassette is designed in the form of a rotational body which is loosely fitted onto the post 11. The tape guide 6 located at the reeling side and positioned adjacent the front edge of the cassette is tightly fitted onto the post 10 so as not to be rotated.
A magnetic tape cassette constructed as described above exhibits substantially reduced frictional resistance at the unreeling side as the tape guide 7 rotates during movement of the magnetic tape 3, and the tape moves very smoothly. Moreover, since the magnetic tape is securely held by means of the tape pad 12 and the guide post 13 located at the tape unreeling side, it is unlikely that the magnetic tape 3 will become loosened regardless of the fact that the tape guide 7 has reduced frictional resistance as a rotational body.
On the other hand, since the tape guide 6 located at the tape reeling side is designed not to be rotated, the magnetic tape 3 is prevented from loosening at this side of the cassette without any provision of a tape holding means such as a tape pad, guide post or the like.
A comparative examination was conducted using conventional video cassettes and improved magnetic tape cassettes embodying the present invention. The conventional cassettes included no tape guide roller, while the improved cassettes included a tape guide roller only at the unreeling side. The following results were obtained at a predetermined travelling speed of the magnetic tape (the table tabulates the number of times that tape movement stopped during a "pass" of the tape, i.e., the movement of the tape from beginning to end):
______________________________________number of at the start- above 50 above 100 above 300pass ing time passes passes passes______________________________________conventional 0 0 2 4type (with noroller)improved type 0 0 0 0(with a singleroller at oneside)______________________________________
The above tests were conducted with the use of rollers made of polyacetal resin and guide poles made of stainless steel, and demonstrate that objectionable stopping of tape movement was encountered with conventional cassettes and was eliminated through use of the present invention.
Thus the present invention succeeds in providing a magnetic tape cassette which is entirely free from any trouble such as troubles caused by frictional resistance during the movement of the magnetic tape, undesirable loosening of the travelling magnetic tape, and others.
As described above, since a magnetic tape cassette in accordance with the present invention is constructed such that it contains two tape guides, one at each of the tape reeling and unreeling sides, wherein just the tape guide located at the unreeling side is designed in the form of a rotational body, it is ensured that the magnetic tape cassette is satisfactorily operated at a substantially reduced frictional resistance with minimized loosening of the travelling magnetic tape, while maintaining the fundamental construction of the tape cassette mechanism. Thus the magnetic tape cassette provides operation at a high level of reliability free from any trouble caused by irregular movement and loosening of the travelling magnetic tape.
The presently preferred embodiment of this invention described above is subject to modification. Thus the invention should be taken to be defined by the following claims. | A reel to reel magnetic tape cassette having a tape guide adjacent the supply reel comprising a rotatable element and a guide adjacent the take up reel which is a non-rotatable element whereby frictional resistance of the tape is reduced at the unreeling side and loosening or slack of the tape during transport is minimized. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Phase Application of International Patent Application No. PCT/BR2012/000010, filed Jan. 19, 2012, which claims priority from Brazilian Patent Application No. PI 1105317-8 filed on Jan. 24, 2011, the disclosures of each of which are hereby incorporated by reference herein in their entirety.
OBJECT OF THE PATENT
The present invention relates to the method for the production of recombinant FVIII in human Sk-Hep-1 cells, comprising von Willebrand Factor (vWF).
The technical object of the present patent application is intended for the cultivation of human cells in suspension and in adhesion and isolation of the culture medium containing the desired protein. The invention further relates to the population of human cells transduced with a vector encoding the clotting protein (FVIII). These cells can be used in the method of production of the protein.
The present invention is then connected with the pharmaceutical industry.
STATE OF THE ART
Hemophilia A patients are treated by means of intravenous infusion of plasma-derived or recombinant FVIII (Mannucci and Giangrande, 2000).
Currently in Brazil, due to the high costs of recombinant plasma, treatment of hemophiliacs is made using factors VIII purified from plasma of normal individuals, which strategy has disadvantages such as risks for viral infections and high demand for plasma from normal donors. Despite being a somewhat effective treatment for hemophilic patients, this is not ideal.
Production of recombinant factor VIII (FVIIIr) in mammal cells represents a safer and more effective alternative for the treatment of individuals with hemophilia A.
In the Brazilian market, each international unit (IU) of plasma-derived factor VIII is sold at an average price of US$ 0.80. Each hemophilic patient uses an average of 30,000 UI per year, which represents US$ 17,000.00/patient/year. Based on these numbers, it is estimated that the country spends about US$ 140,000,000.00 per year in the treatment of these patients. This is an extremely expensive treatment and patients do not receive a suitable prophylactic treatment since there is not enough product on the market and due to contamination risks. Lack of prophylaxis decreases life quality and expectancy of these patients.
All recombinant FVIII available on the market is produced transiently, that is, by plasmid vectors that do not integrate into the genome of cells and murine cells are used for production.
Using non-human cell lines for producing recombinant factor VIII has certain disadvantages. Currently, the main limitation in the production of recombinant FVIII is the low yield of FVIII, which is two orders of magnitude lower than that of other proteins.
The only recombinant FVIII products currently available on the market are under the leadership of three companies (Bayer, Baxter, Wyeth). They are KOGENATE and KOGENATE FS by Bayer, RECOMBINATE by Baxter and REFACTO by Wyeth/Genetics Institut. The recombinant protein is produced in CHO (Chinese Hamster Ovary) or BHK (Baby Hamster Kidney) cells, which are transfected with the full-length or B domain-deleted FVIII. All these recombinant products have similar biological activity than plasma-derived FVIII. Safer formulations have been developed over the years, but these industries use conventional plasmid vectors which provide low expression and the recombinant protein is produced in murine CHO and BHK cell lines, which show different glycosylation patterns thereby yielding a product having high probability for causing an immune reaction in patients.
U.S. Pat. No. 5,362,641 (Heparanase derived from human Sk-Hep-1 cell line) uses Sk-Hep-1 cell line (human liver endothelial cell) to produce recombinant Heparanase.
Patent (WO/2004/092355) EXPRESSION OF PROTEINS IN CORD BLOOD-DERIVED ENDOTHELIAL CELLS and US Patent 2002/0042130 A1 and Lin et al. (2002) describe the production of FVIII in human endothelial cells that can be used in gene therapy protocols.
Patents U.S. Pat. No. 6,228,620, U.S. Pat. No. 5,789,203 and U.S. Pat. No. 5,693,499 describe the co-expression of DNA encoding FVIII light and heavy chains. These embodiments can also be used in accordance with the present invention.
Part of the B-domain of the therapeutic protein used in the present invention is deleted (or removed), which does not take part in coagulant activity of FVIII. Removal of part of the B-domain of FVIII is a known method and patents U.S. Pat. No. 6,346,513, WO 86/06101, WO 92/16557, and EP 0 123 945 describe deletions in sequences encoding FVIII B-domain. In this method, as discussed in the present patent application, cPPT-C(FVIIIDB) vector is used, which is obtained as described in patent IGWS (WO/2004/092355).
Patents EP 1 233 064, US 2002/0165177 and U.S. Pat. No. 6,271,025 disclose the insertion of introns into the cDNA that codes for factor VIII. U.S. Pat. No. 5,422,260 discloses point mutations in FVIII DNA coding sequence.
Factor VIIIr (recombinant) has at least one of the following mutations (EP 1 136 553 A1): —valine at position 162 is substituted with another neutral amino acid residue; —serine at position 2011, is substituted with another hydrophilic amino acid; —valine at position 2223 is substituted with an acidic amino acid. At the B-domain, between positions arginine 740 and glutamic acid 1640, there is a substitution with an arginine-rich “linker” oligopeptide containing 10 to 25 amino acids, preferably 14-20 amino acids. These positions refer to the amino acid sequence of mature human factor VIII (Toole et al. 1984, 312 Nature (5992): 342-7; Wood et al. 1984, 312 Nature (5992): 330-7; Gitschier et al. 1984, 312 Nature (5992): 326-30).
DNA encoding FVIIIDB (FVIII cDNA with part of the B-domain removed) is part of the vector that is used to transduce human cells.
OBJECTS OF THE INVENTION AND SOLUTION PROPOSED TO SOLVE THE CITED PROBLEMS
The present invention uses a human cell line that can be grown in monolayer and/or suspension.
The object of the invention is to provide a safer product (free of potential human viruses), that is cheaper, more stable and produced in sufficient amounts and on an industrial scale to meet the National demand.
The technical improvement observed herein over what already exists is the possibility of obtaining FVIII in a safer manner, since it derives from human cells which are less likely to trigger immune reactions, and on a large scale due to production in suspension. Techniques existing so far do not contemplate how to obtain FVIIIr stably produced in human cells and in suspension.
Under physiological conditions, synthesis of FVIII takes place primarily in hepatocytes and liver sinusoidal endothelial cells (Wion et al., 1985; Zelechowska et al., 1985; Do et al., 1999; Hollestelle et al., 2001). Base on this information, a human liver endothelial cell (Sk-Hep-1) is used to produce recombinant FVIII.
Sk-Hep-1 cell used herein is characterized in that it expresses the von Willebrand Factor (FvW), which is released into the culture medium (Heffelfinger S C et al., 1992). When cells express FVIII, the FvW:FVIII mole ratio in the supernatant may range from 1:1 to 100:1.
FvW stabilizes FVIII. Thus, the production of recombinant FVIII is carried out in a human cell line, Sk-Hep-1.
The blood coagulation FVIII recombinant protein of the present invention has part of the B-domain deleted (FVIIIDB), is produced at high levels in adhesion (monolayers) and suspension cultivation strategies, has good stability, being suitably used in the treatment of hemophilia A.
DEFINITIONS
Recombinant FVIII—is an artificial form of a protein, in this case clotting FVIII, which is created by combining two or more sequences. Recombinant FVIII is created by means of introduction of part of the cDNA human FVIII into a viral DNA, in this case a lentivirus.
B-domain—part of the molecule structure of factor VIII that is not essential for clotting activity thereof.
cDNA—complementary DNA. Molecule that is synthesized by molecular biology techniques using as a template a RNA molecule extracted from the parent producing organism. The molecule is complementary to the RNA.
GFP—Green fluorescent protein. The gene encoding green fluorescent protein is introduced into the cell together with the FVIII coding gene. When produced by cells it acts as an indicator of the production of the molecule of interest (FVIII) and helps in the selection of these producing cells due to the production of green color.
Sk-Hep-1—immortalized human endothelial cell line
FVIIIDB—FVIII recombinant Molecule without part of B-domain
Vector—DNA molecule to which another DNA fragment can bind. A vector can, for example, carry therein an antibiotic resistance gene, replicate autonomously and have a sequence recognizable by enzymes that cut this molecule (endonuclease).
Viral envelope—protein envelope that coats and surrounds all the virus forming material. Each type of virus has different proteins forming this envelope, which provides unique features to each virus.
Plasmid—plasmids are DNA circular molecules capable of reproducing independently from the chromosomal DNA.
Plasmid DNA—same definition as before
Sk-Hep-FVIIIDB—Sk-Hep-1 cell modified by viral transduction and that starts producing factor VIII molecule
pVSV-G—one of the types of viral envelope. Derived from vesicular stomatitis virus. It is used with an envelope for the lentivirus employed herein. Therefore, the HIV viral genetic material is surrounded by an envelope from another virus and is designated pseudotyped (envelope from another virus). This method increases safety to prevent the assembly of a HIV virus.
FACS—Fluorescence Activated Cell Sorting. Process for selecting cells in accordance with its fluorescence.
Cytodex 3—beads of a biologically inert matrix used as microcarriers for growing cells in suspension. It consists of a thin layer of collagen chemically coupled to a dextran matrix.
Cultispher G—macroporous gelatin beads used as microcarriers for growing cells that remain anchored on its surface.
Transduction—the same as viral infection. Process by which viruses produced are placed together with cells in culture. Owing to the intrinsic characteristics of lentiviruses, the viral genetic material fuses or integrates with the genomic material of the cell, thereby modifying its DNA and causing the cell to transform into a FVIII producer.
PBS—Phosphate buffered solution. Aqueous saline solution of 0.9% NaCl buffered with phosphate at pH 7.4.
BRIEF DESCRIPTION OF THE FIGURES
The following description will enable the understanding of the invention as a whole and of each detail thereof
FIG. 1A is the schematic representation of the expression lentiviral vector.
FIG. 1B shows flow cytometry, GFP-positive cells selected and expanded.
FIG. 1C refers to the use of RT-PCR to detect expression of FVIIIr light and heavy chains expressed by the SK-Hep-FVIIIDB population.
FIG. 1D demonstrates the biological activity of recombinant FVIII.
FIGS. 2A and B show the test for determining efficacy of recombinant FVIII in hemophilia A mice.
2 A) Comparison between FVIIIr and FVIIIdp activity profiles over time. FVIIIr shows higher levels of biological activity and is more stable than FVIIIdp.
B) Survival curve after bleeding induced in mice that received FVIIIr (all of them survived), FVIIIdp (all of them survived, and control mice (did not receive FVIII and died until 30 hours after bleeding started).
FIG. 3 illustrates escalation of the generated Sk-Hep-FVIIIBD cell line and analysis of recombinant FVIII production in suspension. The use of two microcarriers is shown to be effective in culturing Sk-Hep-FVIIIDB, which produces up to 1.2 to 1.4 units of FVIIIr/mL.
FIGS. 4A and 4D show, respectively, the kinetics of growth of Sk-Hep FVIIIGFP-CMVdelB cell on Cytodex 3 and Cultispher-G microcarriers in a spinner flask. FIGS. 4B , 4 C, 4 E and 4 F show the formation of cells-microcarriers aggregates in the culture with Cytodex 3 ( 4 B and 4 C) and Cultispher-G ( 4 E and 4 F).
FIG. 5 illustrates the kinetics of FVIIIr production in cultures using Cytodex 3 (A and B) and Cultispher-G (C and D) microcarriers. (A and C) Biological activity and (B and D) Cumulative production over cultivation.
DESCRIPTION OF THE INVENTION
Method
The method for obtaining recombinant FVIII without part of the B-domain comprises the following steps:
1—Producing FVIIIDB-containing virus particles
2—Using the virus particles to infect Sk-Hep-1 cell line
3—Selecting GFP (Green Fluorescent protein used to select producing cells)-positive cells
4—Cultivation in suspension
5—Recovering FVIIIr produced by Sk-Hep-1 cells
Step 1 of the Method: Production of FVIIIDB-Containing Virus Particles
Step 1 consists of producing FVIIIDB-containing virus particles and is carried out by means of the lipofectamine method (Lipofectamine 2000, Gibco).
By using lipofectamine, virus particles are obtained, which have FVIII cDNA with the B-domain partially deleted (FVIIIDB) and the GFP protein. Virus particles are used to insert the gene of interest (in this case FVIIIDB-GFP) into Sk-Hep-1 cells.
Three plasmid vectors are used: a lentiviral vector containing the gene of interest, the plasmid responsible for generating the viral capsid (p8.91) and a plasmid to form the viral envelope (pVSV-G).
The vector containing the gene of interest includes a promoter operably linked to a DNA sequence encoding coagulation factor FVIII. The vector is viral, may be a retroviral vector, more preferably, a lentiviral vector. The lentiviral vector is a HIV-1-derived vector. In addition to HIV-1, lentiviral vectors from HIV-2, simian immunodeficiency virus, equine infectious anaemia virus, feline immunodeficiency virus (FIV) can be used. The schematic representation of the vector is shown in FIG. 1A .
Viruses or virus particles are produced in a mammal cell line (HEK-293) using the 3 plasmid DNAs cited above, which method has already been described by U.S. Pat. No. 5,994,136. Cells produce the viruses which are secreted into the culture medium, which is collected, filtered and stored at −80° C. until use.
Viruses produced by these cells are designated lentiviral vectors or virus particles and are collected and used in step 2.
Step 2 of the Method: Use of Virus Particles to Infect Sk-Hep-1 Cell Line
Next (step 2), human Sk-Hep-1 cell is transduced with FVIIIDB-containing virus particles.
Viruses produced in the previous step (lentiviral vectors) are used in the transduction procedure when the genetic material of interest (human FVIIIr cDNA) is carried to host cell genome, thus resulting in stable integration into the cell genome. After integration of the viral genome material with the DNA of the cell, transcription of the transgene, and consequently, synthesis of recombinant protein, begins. Usually, the recombinant protein can be detected a few hours after transduction.
Step 3: Selection of GFP-Positive Cells
The lentiviral construct used in the present patent has GFP cDNA, such that transduction efficiency is measured by flow cytometry (FACS). Fluorescent cells detected by the flow cytometer indicate that infection and integration took place and since they express GFP, they also express FVIII.
After selection by FACS, evaluation of the recombinant protein production level is made by conventional RT-PCR and by an activity, chromogenic assay.
Step 4: Cultivation in Suspension
Expansion of Sk-Hep-FVIIIDB cell may be carried out in spinner bootles with microcarriers.
The cell line produced in accordance with the present invention should be previously expanded in bottles up to the concentration of 1×10 5 cells/mL and added to the previously hydrated, sterilized and balanced microcarriers in serum-containing growth medium at 37° C.
Step 5: Recovery of Recombinant FVIII Produced by Sk-Hep-FVIIIDB Cells
In this step recombinant FVIII is isolated from Sk-Hep-FVIIIDB cells.
The quantity of the purified protein during and after the purification procedure may be monitored (or measured) by ELISA and by coagulation assays.
The composition obtained by this method for the production of FVIII is subjected to a viral inactivation treatment and purification to remove chemical substances.
Example of Obtainment
The invention can be obtained by the previously cited steps, which are explained below:
Step 1 of the Method: Production of FVIIIDB-Containing Virus Particles
Step 1 consists of producing FVIIIDB-containing virus particles and is carried out by means of the lipofectamine method (Lipofectamine 2000, Gibco).
Production of virus particles using lipofectamine é a method where 3 DNAs are used, namely 10 ug of lentiviral vector, 6.5 ug of 8.91 vector (capsid) and 3.5 ug of VSVG vector (envelope). Prior to adding the DNAs, the culture medium of HEK-293 cells is replaced. 7 ml of DMEM containing 10% fetal bovine serum (FBS) are added.
In a 15 ml tube, pipette 8.91 and VSVG DNAs into 1.5 ml of serum-free DMEM medium. In another tube, mix 1.5 ml of serum-free DMEM medium with 60 ul of Lipofectamine. Leave both tubes at ambient temperature for 5 minutes.
Next, mix the 2 tubes and incubate for 20 minutes at room temperature. Add the resulting 3 ml to the plate with cells and incubate at 37° C. 5% CO2. After 6 hours, replace the medium on the plates (7 ml of DMEM medium with 10% FBS) and incubate for at least 48 hours at 37° C. 5% CO2. The culture supernatant containing the viruses produced by the cells is collected after 48 hours, filtered and fractionated into 1 ml aliquots.
Step 2 of the Method: Use of Virus Particles to Infect Sk-Hep-1 Cell Line
Transduction may be carried out in adherent cells as well as in cultures in suspension. Several transduction techniques using both viral and non-viral vectors have been optimized to cell culture in suspension.
Transductions are carried out in 24-well plates. Twenty-four hours prior to transduction 2 to 5×10 4 Sk-Hep-1 cells are seeded in DMEM medium with 10% FBS for transduction to take place during the exponential phase of cell growth. To each well the previously produced and collected virus is added with no dilution. Cells are centrifuged (90 minutes, 1250×g, 32° C.), incubated for 15 to 18 hours in a moist CO 2 incubator, washed with PBS and expanded with the appropriate medium.
Step 3: Selection of GFP-Positive Cells
Transduction efficiency is measured by flow cytometry (FACS).
For the FACS procedure, cells are trypsinized with trypsin/EDTA, washed with the appropriate buffer (1% fetal bovine serum/0.1% sodium azide in PBS) and 1% formaldehyde in PBS is added. Non-transduced cells, which do not express GFP, are used as a negative control, that is, Sk-Hep-1 cells which have not received any viruses are also passed through the flow cytometer to evaluate basal fluorescence of cells. Basal fluorescence is compared with that of transduced cells
Identification and purification of the cell population harboring the FVIIIDB-containing lentiviral vector is shown in FIG. 1B .
GFP-positive cells selected by flow cytometry can be re-cultured in DMEM medium with 10% FBS at a temperature of 37° C. and 5% CO2.
After selection by FACS, evaluation of the recombinant protein production level is made by conventional RT-PCR and by an activity, chromogenic assay. The chromogenic assay is made by ELISA or luminescence. The chromogenic assay used was Immuno Chrom (Immuno GmbH, Germany).
Step 4: Cultivation in Suspension
Expansion of Sk-Hep-FVIIIDB cell may be carried out in spinner booties with microcarriers. Microcarrier cell culture allows for cultivation of anchorage-dependent cell lines at an industrial scale to meet the commercial demand. In this type of culture, cell grows adhered to the surface of small beads or inside the pores of macroporous particles which are suspended in a culture medium. The system allows for control of culture parameters (pH, dissolved oxygen concentration, temperature, among others), reduces the need for high amounts of culture medium, reduces labor and contamination risks.
First, microcarriers should be hydrated and sterilized, as is known by the skilled person.
Microcarriers can be, for instance, Cytodex 3 (GE Healthcare) and Cultispher-G (Percell Biolytica).
Re-hydration of microcarriers Cultispher-G was performed in calcium- and magnesium-free PBS (50 ml/g dry Cultispher-G) for at least one hour, more preferably 2 to 3 hours, at room temperature. Without removing PBS, microcarriers were sterilized (121° C., 15 min, 15 psi).
Re-hydration of microcarriers Cytodex 3 was performed in calcium- and magnesium-free PBS (50 ml/g dry Cytodex 3) for 3 to 6 hours at room temperature. Sterilisation was performed as explained above for microcarriers Cultispher-G.
Sk-Hep FVIIIGFP-CMVdelB cells can be cultured in culture bottles, such as spinner flasks, in incubators at 37° C. and 5% CO2. The cell line obtained in the present invention should be first expanded in bottles up to the concentration of 5×10 4 cells/mL up to 2×10 5 cells/mL, preferably about 1×10 5 cells/mL, and then added to previously hydrated, sterilized and balanced microcarriers in a serum-containing growth medium at 37° C. and up to a concentration of about 3.0 g/L Cytodex 3 and about 1.0 g/L Cultispher-G.
Culture was initiated with ⅓ the final volume and intermittent stirring (stirring for 2 minutes at 20-50 rpm, more preferably at 30-40 rpm, followed by about 30 minutes with no stirring) for the first 3 hours for better adhesion of cells to the microcarrier. After this period of time, DMEM culture medium containing 10% FBS was added to make the final volume and stirring was kept constant at 30 to 40 rpm, more preferably, at 40 rpm. Replacements of 50% of the volume of the culture medium were performed when the pH fell to the range of 6.5 to 7.2 after sedimentation of cell-containing microcarriers.
Samples were collected daily for monitoring cell density, viability and production of recombinant factor VIII.
Results of production escalation and analysis of FVIII activity during cultivation are shown in FIG. 3 .
FIGS. 4A and 4D , in turn, show cell growth using Cytodex 3 and Cultispher-G. Sk-Hep FVIIIGFP-CMVdelB cell was capable of growing on the two microcarriers tested for a period of more than 300 hours of cultivation, achieving a maximal cell density of 3.17×10 6 cel/mL for Cytodex 3 ( FIG. 4A ) and 1.74×10 6 cel/mL for the Cultispher-G microcarrier ( FIG. 4D ).
FIG. 5 shows data of FIG. 3 separately. It can be noted that the production profile of recombinant factor VIII was similar in both cultures ( FIGS. 5A and B). The average production of rFVIII was 0.9±0.4 IU/mL on Cytodex 3 microcarrier and 1.0±0.4 IU/mL on Cultispher-G microcarrier. Total cumulative production was 300 UI in the culture with Cytodex 3 (334 hours) and 480 UI in the culture with Cultispher-G (310 hours) ( FIGS. 5C and D). Even after 200 hours of culture, Sk-Hep FVIIIGFP-CMVdelB cell was capable of producing higher levels at 1.0 UI/mL
Step 5: Recovery of Recombinant FVIII Produced by Sk-Hep-FVIIIDB
In this step recombinant FVIII is isolated from −Hep-FVIIIDB cells. Suitable purification methods include, but are not limited to, immunoaffinity chromatography, ion exchange chromatography and so on, and combinations thereof. Execution purification protocols for human blood coagulation factors are disclosed in patent documents: WO 93/15105, EP 0 813 597, WO 96/40883, 96/15140/50 and U.S. Pat. No. 7,247,707 B2. They can be tailored to the necessary demands to isolate recombinant factors VIII and IX.
The quantity of the purified protein during and after the purification procedure may be monitored (or measured) by ELISA and by coagulation assays. The composition obtained by this method of producing FVIII is subjected to a viral inactivation treatment that includes heat treatment (either dry or in liquid state, with or without the addition of chemical substances, including protease inhibitors). After viral inactivation a further purification step may be required to remove chemicals. Patent document WO 93/15105 describes a technique to isolate factor VIII from blood plasma by ion exchange chromatography in high purity.
Selection by Flow Cytometry
The lentiviral construct used in the present invention has GFP cDNA, such that transduction efficiency was measured by flow cytometry (FACS). For the FACS procedure, cells were trypsinized with trypsin/EDTA, washed with FACS buffer (1% FBS/0.1% sodium azide in PBS) and 1% formaldehyde in PBS is added. Measurement and selection has been carried out in a FACScan apparatus using Becton Dickinson CellQuest software. Non-transduced cells, which do not express GFP.
Flow cytometry analysis has shown a population prior to selection containing 8.4% GFP-positive cells and after selection the population obtained was 73% GFP-positive ( FIG. 1A ).
Conventional RT
cDNA molecules were synthesized from 4 μg of total RNA by incubating 50 ng/μL oligo FVIII or β-actin, 10 mM dNTPs, in a volume of 10 μL at 65° C. for 5 minutes, followed by cooling on ice for 2 minutes. Thereafter, a mixture of 2 μL of RT-Buffer 10×, 4 μL of 25 mM MgCl, 2 μL of 0.1 M DTT and 1 μL of ribonuclease inhibitor was added to the mixture, thus yielding a final volume of 19 μL. The reaction was incubated at 25° C. for 2 minutes, 1 μL of SuperScript II RT (50 units) was added to each sample followed by 25° C. for 10 minutes. The reaction was then incubated at 42° C. for 50 minutes and denatured at 70° C. for 15 minutes and put on ice, with the addition of 1 μL of RNAse H and incubation at 37° C. for 20 minutes. Samples incubated with no reverse transcriptase enzyme have been prepared as a control. After reverse transcription, 1 μL of cDNA was used in PCR amplification with specific oligonucleotides for FVIII and β-actin.
Amplification of regions of recombinant FVIII is demonstrated in FIG. 1B .
Quantification of FVIII Activity by a Chromogenic Assay
The chromogenic assay measures FVIII activity via production of factor Xa, rather than by the clotting time, as in the TTPA assay. Two reagents (A: phospholipids and albumin; B: FIX, FX, Ca2+, albumin and thrombin) were added to the samples. Factor VIII present in the samples acts as a co-factor together with FIX, Ca2+ and phospholipids to transform FX into FXa. FXa breaks the p-nitroaniline substrate down, thereby yielding an yellow color whose concentration is measured at 405 nm. The chromogenic assay used was Immuno Chrom (Immuno GmbH, Germany), according to the manufacturer's instructions. The assay was carried out in 96-well microplates. For each microplate, a standard curve of defined dilutions of human plasma was made. The minimum detection level of the assay is for samples showing ≧1% activity.
The activity of recombinant FVIII was found to be 4 UI/mL/10E6 cells. It can be verified by RT-PCR (reverse transcription polymerase chain reaction—reverse transcriptase reaction followed by a polymerase chain reaction) used to detect expression of FVIIIr light and heavy chains expressed by the SK-Hep-FVIIIDB population ( FIG. 1C ). It is noted that the cell line obtained according to the present invention produces 4 times more FVIII than the amount of FVIII in human plasma.
Test in an Animal Model—Functionality of Recombinant Protein
To test the in vivo functionality of the recombinant protein obtained according to the present invention, the following experiment was performed.
Functionality of the recombinant protein was tested in hemophilia A mice and compared with FVIIIdp efficiency (derived from plasma). Five mice were given 1 UI of recombinant FVIII or FVIIIdp and biological activity was monitored for 30 minutes, 1 hour, 2 hours, 3 hours and 6 hours after FVIII infusion. The results are depicted in FIG. 2A .
Hemophilia A mice were anesthetized and were given 50 UI of FVIIIDB/Kg, then bleeding was provoked by cutting 3 mm of the tail. The survival curve is shown in FIG. 2B . All animals that were given FVIIIDB survived, showing effectiveness of the FVIIIDB obtained according to the present invention in correcting hemophilia A. | The present invention refers to: 1) the method for the production of recombinant FVIII in human Sk-Hep-1 cells, comprising von Willebrand Factor (vWF) and 2) the population of human cells transduced with a vector encoding the clotting protein (FVIII). The technical object of the present patent application is intended for the cultivation of human cells in suspension and in adhesion and isolation of the culture medium containing the desired protein. The object of the invention is to provide a safer product (free of potential human viruses), that is cheaper and more stable, by means of a method that provides sufficient amounts and on industrial scale to meet the National demand. | 2 |
FIELD OF THE INVENTION
The present invention relates generally to the field of oil and gas well drilling. More particularly, the present invention relates to a method and system for directional drilling in which the drill string is rotated back and forth between selected surface measured torque magnitudes without changing the tool face angle, thereby to reduce friction between the drill string and the well bore.
BACKGROUND OF THE INVENTION
It is very expensive to drill bore holes in the earth such as those made in connection with oil and gas wells. Oil and gas bearing formations are typically located thousands of feet below the surface of the earth. Accordingly, thousands of feet of rock must be drilled through in order to reach the producing formations. Additionally, many wells are drilled directionally, wherein the target formations may be spaced laterally thousands of feet from the well's surface location. Thus, in directional drilling, not only must the depth but also the lateral distance of rock must be penetrated.
The cost of drilling a well is primarily time dependent. Accordingly, the faster the desired penetration location, both in terms of depth and lateral location, is achieved, the lower the cost in completing
While many operations are required to drill and complete a well, perhaps the most important is the actual drilling of the bore hole. In order to achieve the optimum time of completion of a well, it is necessary to drill at the optimum rate of penetration and to drill in the minimum practical distance to the target location. Rate of penetration depends on many factors, but a primary factor is weight on bit.
Directional drilling is typically performed using a bent sub mud motor drilling tool that is connected to the surface by a drill string. During sliding drilling, the drill string is not rotated; rather, the drilling fluid circulated through the drill string cause the bit of the mud motor drilling tool to rotate. The direction of drilling is determined by the azimuth or face angle of the drilling bit. Face angle information is measured downhole by a steering tool. Face angle information is typically conveyed from the steering tool to the surface using relatively low bandwidth mud pulse signaling. The driller attempts to maintain the proper face angle by applying torque or drill string angle corrections to the drill string.
Several problems in directional drilling are caused by the fact that a substantial length of the drill string is in frictional contact with and supported by the borehole. Since the drill string is not rotating, it is difficult to overcome the friction. The difficulty in overcoming the friction makes it difficult for the driller to apply sufficient weight to the bit to achieve an optimal rate of penetration. The drill string exhibits stick/slip friction such that when a sufficient amount of weight is applied to overcome the friction, the drill the weight on bit tends to overshoot the optimum magnitude.
Additionally, the reactive torque that would be transmitted from the bit to the surface through drill string, if the hole were straight, is absorbed by the friction between the drill string and the borehole. Thus, during drilling, there is substantially no reactive torque at the surface. Moreover, when the driller applies drill string angle corrections at the surface in an attempt to correct the bit face angle, a substantial amount of the angular change is absorbed by friction without changing the face angle in stick/slip fashion. When enough angular correction is applied to overcome the friction, the face angle may overshoot its target, thereby requiring the driller to apply a reverse angular correction.
It is known that the frictional engagement between the drill string and the borehole can be reduced by rocking the drill string back and forth between a first angle and a second angle. By rocking the string, the stick/slip friction is reduced, thereby making it easier for the driller to control the weight on bit and make appropriate face angle corrections.
SUMMARY OF THE INVENTION
The present invention provides a method and system for directional drilling that reduces the friction between the drill string and the well bore. According to the present invention, a downhole drilling motor is connected to the surface by a drill string. The drilling motor is oriented at a selected tool face angle. The drill string is rotated at the surface location in a first direction until a first torque magnitude is reached, without changing the tool face angle. The drill string is then rotated in the opposite direction until a second torque magnitude is reached, again without changing the tool face angle. The drill string is rocked back and forth between the first and second torque magnitudes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view of a directional drilling system.
FIG. 2 is a block diagram of a directional driller control system according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and first to FIG. 1, a drilling rig is designated generally by the numeral 11 . Rig 11 in FIG. 1 is depicted as a land rig. However, as will be apparent to those skilled in the art, the method and system of the present invention will find equal application to non-land rigs, such as jack-up rigs, semisubmersibles, drill ships, and the like.
Rig 11 includes a derrick 13 that is supported on the ground above a rig floor 15 . Rig 11 includes lifting gear, which includes a crown block 17 mounted to derrick 13 and a traveling block 19 . Crown block 17 and traveling block 19 are interconnected by a cable 21 that is driven by draw works 23 to control the upward and downward movement of traveling block 19 . Traveling block 19 carries a hook 25 from which is suspended a top drive 27 . Top drive 27 supports a drill string, designated generally by the numeral 31 , in a well bore 33 . Top drive 27 can be operated to rotate drill string 31 in either direction.
According to an embodiment of the present invention, drill string 31 is coupled to top drive 27 through an instrumented sub 29 . As will be discussed in detail hereinafter, instrumented top sub 29 includes sensors that provide drill string torque information according to the present invention.
Drill string 31 includes a plurality of interconnected sections of drill pipe 35 a bottom hole assembly (BHA) 37 , which includes stabilizers, drill collars, and a suite of measurement while drilling (MWD) instruments including a steering tool 51 . As will be explained in detail hereinafter, steering tool 51 provides bit face angle information according to the present invention.
A bent sub mud motor drilling tool 41 is connected to the bottom of BHA 37 . As is well known to those skilled in the art, the face angle of the bit of drilling tool 41 used to control azimuth and pitch during sliding directional drilling. Drilling fluid is delivered to drill string 31 by mud pumps 43 through a mud hose 45 . During rotary drilling, drill string 31 is rotated within bore hole 33 by top drive 27 . As is well known to those skilled in the art, top drive 27 is slidingly mounted on parallel vertically extending rails (not shown) to resist rotation as torque is applied to drill string 31 . During sliding drilling, drill string 31 is held in place by top drive 27 while the bit is rotated by mud motor 41 , which is supplied with drilling fluid by mud pumps 43 . The driller can operate top drive 27 to change the face angle of the bit of drilling tool 41 . Although a top drive rig is illustrated, those skilled in the art will recognize that the present invention may also be used in connection with systems in which a rotary table and kelly are used to apply torque to the drill string The cuttings produced as the bit drills into the earth are carried out of bore hole 33 by drilling mud supplied by mud pumps 43 .
Referring now to FIG. 2, there is shown a block diagram of a preferred system of the present invention. The system of the present invention includes a steering tool 51 , which produces a signal indicative of drill bit face angle. Typically, steering tool 51 uses mud pulse telemetry to send signals to a surface receiver (not shown), which outputs a digital face angle signal. However, because of the limited bandwidth of mud pulse telemetry, the face angle signal is produced at a rate of once every several seconds, rather than at the preferred five times per second sampling rate. For example, the sampling rate for the face angle signal may be about once every twenty seconds.
The system of the present invention also includes a drill string torque sensor 53 , which provides a measure of the torque applied to the drill string at the surface. The drill string torque sensor may implemented as a strain gage in instrumented top sub 29 (illustrated in FIG. 1 ). The torque sensor 53 may also be implemented as a current measurement device for an electric rotary table or top drive motor, or as pressure sensor for an hydraulically operated top drive. The drill string torque sensor 53 provides a signal that may be sampled at the preferred sampling rate of five times per second.
In FIG. 2, the outputs of sensors 51 and 53 are received at a processor 55 . Processor 55 is programmed according to the present invention to process data received from sensors 51 - 53 . Processor 55 receives user input from user input devices, such as a keyboard 57 . Other user input devices such as touch screens, keypads, and the like may also be used. Processor 55 provides visual output to a display 59 . Processor 55 also provides output to a drill string rotation controller 61 that operates the top drive ( 27 in FIG. 1) or rotary table to rotate the drill string according to the present invention.
According to the present invention, drilling, tool 41 is oriented at tool face angle selected to achieve a desired trajectory. As drilling tool 41 is advanced into the hole, processor 55 operates drill string rotation controller 61 to rotate drill string 35 in a first direction while monitoring drill string torque with torque sensor 53 and tool face angle with steering tool 51 . As long as the tool face angle remains constant, rotation controller 61 continues to rotate drill string 35 in the first direction. When the steering tool 51 senses a change in tool face angle, processor 55 notes the torque magnitude measured by torque sensor 53 and actuates drill string rotation controller 61 to reverse the direction of rotation of drill string 31 . Torque is a vector having a magnitude and a direction. When torque sensor 53 senses that the magnitude of the drill string torque has reached the magnitude measured in the first direction, processor 55 actuates rotation controller 61 reverse the direction of rotation of drill string 31 . As drilling progresses, processor 55 continues to monitor drill torque with torque sensor 53 and actuates rotation controller 61 to rotate drill string 31 back and forth between the first torque magnitude and the second torque magnitude. The back and forth rotation reduces or eliminates stick/slip friction between the drill string and the well bore, thereby making it easier for the driller to control weight on bit and tool face angle.
Alternatively, the torque magnitude may be preselected by the system operator. When the torque detected by the torque sensor 53 reaches the preselected value, the processor 55 sends a signal to the controller 61 to reverse direction of rotation. The rotation in the reverse direction continues until the preselected torque value is reached again. In some embodiments, the preselected torque value is determined by calculating an expected rotational friction between the drill string ( 35 in FIG. 1) and the wellbore wall, such that the entire drill string above a selected point is rotated. The selected point is preferably a position along the drill string at which reactive torque from the motor 41 is stopped by friction between the drill string and the wellbore wall. The selected point may be calculated using “torque and drag” simulation computer programs well known in the art. Such programs calculate axial force and frictional/lateral force at each position along the drill string for any selected wellbore trajectory. One such program is sold under the trade name WELLPLAN by Landmark Graphics Corp., Houston, Tex.
While the invention has been disclosed with respect to a limited number of embodiments, those of ordinary skill in the art, having the benefit of this disclosure, will readily appreciate that other embodiments may be devised which do not depart from the scope of the invention. Accordingly, the scope of the invention is intended to be limited only by the attached claims. | A method of and system for directional drilling reduces the friction between the drill string and the well bore. A downhole drilling motor is connected to the surface by a drill string. The drilling motor is oriented at a selected tool face angle. The drill string is rotated at said surface location in a first direction until a first torque magnitude without changing the tool face angle. The drill string is then rotated in the opposite direction until a second torque magnitude is reached, again without changing the tool face angle. The drill string is rocked back and forth between the first and second torque magnitudes. | 4 |
RELATED APPLICATIONS
The present invention is a Continuation In Part of U.S. patent application Ser. No. 10/457,659 filed on Jun. 9, 2003, which claims priority to Provisional Application Ser. No. 60/389,080 filed Jun. 14, 2002.
FIELD OF THE INVENTION
The present invention is directed to a subset of electric propulsion, pulsed plasma thrusters, for maneuvering of a mass in microgravity.
BACKGROUND OF THE INVENTION
A pulsed plasma thruster is typically used to maneuver spacecraft and satellites in microgravity. The thruster employs a series of electric current pulses of limited duration and varying frequency between a pair of electrodes creating a series of electric arcs. The electric arcs pass over the surface of a propellant, increasing the surface temperature of the propellant, thereby forming an ionized gas, known as a plasma. The plasma is then exhausted from the device to produce thrust.
The two primary classifications of pulsed plasma thrusters are electrothermal and electromagnetic. In the case of an electrothermal thruster, the heating and/or ablation process results in a high chamber pressure accompanied by high plasma resistance, exhausting the plasma from the thruster by supersonic gas expansion. Alternatively, in the case of an electromagnetic thruster, chamber pressures and plasma resistance remain low, helping to facilitate high ionization fractions. Within an electromagnetic thruster, the flow of current between the electrodes induces electric and magnetic fields resulting in electromagnetic body forces which accelerate the ionized particles from the thruster. In comparison with electrothermal thrusters, electromagnetic thrusters are phenomenologically more complex. They are also considerably more difficult to model analytically and technologically more difficult to implement.
More specifically, electrothermal pulsed plasma thrusters may be characterized by high chamber pressures, a high plasma resistance, and substantial temperature and density gradients, typically followed with supersonic gas expansion through an exhausting insulating nozzle. The nozzle is generally insulating to reduce heat loss in the nozzle and encourage a modest amount of electromagnetic thrust. The high plasma resistance promotes efficient transfer of the capacitively stored energy into the plasma.
On the other hand, electromagnetic pulsed plasma thrusters may be characterized by low chamber pressures, a low plasma resistance, high ionization fractions, and pulsed electric arcs which traverse the region between the electrodes in a manner substantially perpendicular to the flow of the exhausting plasma. In the case of an electromagnetic pulsed plasma thruster, the addition of a supersonic nozzle usually provides little to no benefit since the low chamber pressures do not facilitate significant supersonic gas expansion. The primary contribution to the thrust is produced by the current's self-induced electromagnetic body forces. The present invention has found that a conductive nozzle, though ineffective at encouraging supersonic gas expansion due to low chamber pressures, aids in producing significantly greater electromagnetic body forces. Furthermore, a low plasma resistance promotes stronger electromagnetic body forces and in turn greater thrust.
Electrothermal and electromagnetic pulsed plasma thrusters may be further categorized as either parallel-plate or coaxial. In a parallel-plate configuration, the electric arc passes between a pair of electrodes that are situated parallel to the direction of the plasma flow as shown in FIG. 1 . In a coaxial configuration, the electric arc passes between a centrally located electrode and an annular electrode as shown in FIG. 2 . Generally, electromagnetic pulsed plasma thrusters utilize the parallel-plate configuration. In order to maximize electromagnetic body forces, the current path is necessarily substantially perpendicular to the flow of ionized particles. As FIG. 1 illustrates, the geometry of a parallel-plate design inherently provides the optimal current path relative to the flow of ionized particles. While significantly more difficult to achieve with a coaxial configuration, the present invention's geometry manages to encourage a current path substantially perpendicular to the flow of ionized particles in a coaxial configuration.
Prior art pulsed thruster systems can be found in U.S. Pat. Nos. 6,295,804 and 5,924,278 to common inventor Burton. Said systems utilize a high chamber pressure, accompanied by a high plasma resistance, to accelerate the plasma, thus classifying the systems as predominantly electrothermal. The systems accelerate the plasma through an insulating nozzle, facilitating supersonic gas expansion. The systems expel the plasma from the cavity in a flow path that is substantially parallel to the electric arc and current path within the cavity.
The present invention, predominantly electromagnetic, improves upon the prior art by maintaining a low plasma resistance and in turn producing strong electromagnetic body forces, resulting in significantly higher efficiencies and more consistent pulse-to-pulse performance. While the present invention utilizes a diverging nozzle, the nozzle is necessarily conducting, unlike to the aforementioned thrusters. Though the conducting nozzle enables some supersonic gas expansion, the major benefit is that the nozzle exploits electromagnetic phenomena to further accelerate the plasma. The electric arc and current path is also necessarily substantially perpendicular to the flow path of the plasma to facilitate electromagnetic acceleration.
SUMMARY OF THE INVENTION
The present invention provides for an advanced lightweight pulsed plasma thruster with high electromagnetic thrust in a coaxial geometry. The thruster includes a plasma generating section that has a centrally located electrode, radially fed propellant bars and a conducting annular electrode. The propellant material exposed to the electric discharge forms an ionized gas as a result of being heated by the electric arc. The thruster also includes an exhaust section having a conducting cavity diverging away from the centrally located electrode. The thruster is further connected to an electric pulse power supply unit such that the centrally located electrode and the annular electrode generate short-duration axisymmetric electric arcs with a current path across the surface of the propellant, such that the propellant material being heated by the electric arcs produces ionized gas in the plasma generating section. The percentage of ionization is significantly higher, and the plasma resistance is significantly lower, than previous thrusters of this type. The ionized gas is expelled from the thruster at high velocity to produce a thrust pulse. A sequence of thrust pulses, averaged over time, produce an average thrust for maneuvering a mass in microgravity. The thrust produced by the pulsed plasma thruster has an electromagnetic thrust component which is on the order of 60% or larger of the total thrust. The plasma resistance is less than 15 milliohms.
In addition, a low-inductance parallel-plate or coaxial transmission line connects the thruster electrodes to the pulsed electric power supply unit. The design of the low inductance transmission line provides for pulses with higher peak currents and fewer oscillations, which in turn induces a lower plasma resistance in the thruster, yielding greater electromagnetic thrust.
In one embodiment of the present invention a pulsed plasma thruster includes:
a cylindrical plasma generating section having an annular cross-section with at least one propellant feed opening;
an exhaust section having a minimum radius and a diverging section that is located downstream of the plasma generating section and having a wall that is substantially electrically conducting to form an annular electrode and nozzle;
a central electrode, mounted on a conductive shaft, being centrally located within the plasma generating section;
an insulating member secured to and separating the central electrode from the annular electrode;
an insulating sleeve positioned about the conductive shaft and secured to the insulating member;
at least one solid propellant bar that forms an ionized gas as a result of being heated, a first end of the propellant bar being radially fed through the at least one opening of the plasma generating section;
a means for initiating an electric arc between the central electrode and the annular electrode to generate an electric arc having a current path across a surface portion of the propellant bar, such that propellant material is heated to produce ionized gas, which is electromagnetically expelled from the thruster at high velocity to produce thrust.
The thruster may also include a minimum annular electrode radius defined by the plasma generating section that is the minimum diameter of the exhaust section which enables a low pressure and a low plasma resistance within the exhaust section to provide thrust with an increased electromagnetic component during the generation of the electric arc.
The thruster may also include a central electrode that is conical in shape to increase the electromagnetic thrust component.
The thruster may further include a ratio between the minimum radius of the nozzle and the central electrode radius that is between 3.0 and 10.0 to provide thrust with an electromagnetic thrust component that is greater than an electrothermal thrust component.
The thruster may also include an insulating member that separates the central electrode from the annular electrode so as to maintain a non-conductive path to protect against electrodes shorting as a result of carbon deposits on the cavity surfaces.
Numerous advantages and features of the invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, and from the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Better understanding of the aforementioned invention may be had by referencing the accompanying drawings, wherein:
FIG. 1 is a simplified representation of a parallel-plate pulsed plasma thruster;
FIG. 2 is a simplified representation of a coaxial pulsed plasma thruster;
FIG. 3 is a system diagram of the present invention;
FIG. 4 is a perspective view of the present invention;
FIG. 5 is an axial view of the present invention;
FIG. 6 is an exploded view of the present invention; and
FIG. 7 is a cross-sectional view of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
While the invention is susceptible to embodiments in many different forms, the preferred embodiments of the present invention are shown in the drawings ( FIG. 3-7 ) and will be described in detail herein. It should be understood, however, that the present disclosure is to be considered an exemplification of the principles of the invention and is not intended to limit the spirit or scope of the invention and/or the embodiments illustrated. It is to be understood that no limitation with respect to the specific methods and apparatus illustrated herein is intended or should be inferred.
A schematic of a pulsed thruster system 20 , in accordance to the present invention, is shown in FIG. 3 . The system 20 includes a primary power supply unit 22 , a thruster power supply unit 24 , a control circuit 26 , an ignition circuit 28 , a spark generating device 30 , a capacitor 32 , and a thruster 100 . The primary power supply 22 is coupled to the thruster power supply 24 , which in turn is coupled to the ignition circuit 28 and selectively coupled to the capacitor 32 . The ignition circuit 28 is coupled to the spark generating device 30 , and receives commands from the control circuit 26 . The capacitor 32 is coupled across the thruster 100 via low inductance transmission lines 46 .
Referring now to FIGS. 4-7 , the pulsed plasma thruster 100 includes an electrical connection region 102 for establishing electrical connections to the transmission lines 46 and a plasma generating and exhaust region 104 . The plasma generating and exhaust region 104 generates plasma from a propellant and exhausts the plasma at a high velocity to generate thrust. Positioned between the electrical connecting region 102 and the plasma generating and exhaust region 104 is an electrically conducting structural tube 106 , which accommodates a spring mount 137 . The spring mount 137 has springs 138 attached to it that separately feed multiple solid propellant bars 110 into a plasma generating section 112 . The solid propellant bars 110 are curved, permitting a more compact and efficient design than the common straight fuel bar. As the propellant bars 110 are heated, the spring mount 137 maintains a constant feeding into the plasma generating section 112 .
The plasma generating and exhaust region 104 is defined by a circular body 114 having an annular cross-section. The circular body 114 has multiple propellant feed openings 118 aligned radially with the center of the plasma generating section 112 for which multiple solid propellant bars 110 are fed towards a central electrode 120 . The central electrode 120 is positioned at the center of the circular body 114 .
The circular body 114 further includes an exhaust section 122 with a conductive interior cavity wall 126 that diverges radially away from the plasma generating section 112 to define a diverging nozzle. The circular body 114 is made of an electrically conductive material, such that it forms the annular electrode. The exhaust section 122 also includes oblique ports 128 for receiving spark generating devices (not shown).
The interior cavity wall 126 has a bottom portion referred to as the minimum annular electrode radius 127 that forms the inlet of the diverging nozzle. The minimum annular electrode radius 127 is in close proximity to the plasma generating section 122 and more importantly in close proximity to the central electrode 120 . The radius ratio between the minimum annular electrode radius 127 and the central electrode 120 is a critical element in creating the higher electromagnetic thrust component and is further explained below.
Internally, the plasma generating section 112 houses various components that include a cavity insulator 130 that separates the central electrode 120 from the annular electrode 124 and a forward insulator 132 that mates the cavity insulator 130 to an insulating sleeve 154 that maintains the insulation around a central conductive shaft 134 . The central conductive shaft 134 sustains the electrical current from the capacitor 32 to the central electrode 120 . The plasma generating section 112 is secured to the structural tube 106 by a forward conducting mount 136 .
As mentioned above, the structural tube 106 accommodates the spring mount 137 which slides onto the structural tube 106 and is bolted to the forward conducting mount 136 . The springs 138 attached to the spring mount 137 include one end 140 that is positioned in a notch 142 located in the bottom portion of the propellant bars 110 . The propellant bars 110 , preferably TEFLON, are guided into propellant feed openings 118 by curved propellant support rods 144 . The propellant support rods 144 have one end 146 secured to a rear conductor mount 150 and the other end 148 secured to apertures 152 located above the propellant feed openings 118 in the circular body 114 and are positioned within grooves 111 defined on the propellant bars 110 .
The structural tube 106 is constructed from a conductive material and includes an internal insulating sleeve 154 , which has protruding ends 156 and 158 . The internal insulating sleeve 154 is hollow to accommodate the conductive shaft 134 . One end 158 of the insulating sleeve 154 is fitted through the forward conducting mount 136 and into the forward insulator 132 , while the other end 156 is fitted within the rear insulator cap 160 such that the conductive shaft 134 and the central electrode 120 are completely insulated from the annular electrode 124 and outside conductive nature of the thruster 100 . The rear conductor mount 150 is positioned about the exterior surface of the structural tube 106 , with the rear insulator cap 160 abutting the rear conductor mount 150 to maintain the insulation between the two electrodes.
In operation, the primary power supply unit 22 provides power to the thruster power supply unit 24 , which charges the capacitor 32 . The capacitor 32 , in turn, applies a voltage across the thruster 100 , (between the central electrode 120 and annular electrode 124 ). In accordance with a signal received from the control circuit 26 , the ignition circuit 28 fires the spark generating devices 30 . The firing of the spark generating devices 30 sprays ionized particles into the plasma generating section 112 allowing current to flow between the central electrode 120 and the annular electrode 124 completing the circuit. As the arc heats the surface of the propellant bars 110 , ionized gas or plasma forms. The arc further induces a strong electromagnetic field, accelerating the plasma due to electromagnetic body forces, in turn creating thrust.
The electromagnetic thrust fraction, β, of the present invention is designed to be significantly greater than prior coaxial pulsed plasma thrusters. The electromagnetic thrust fraction, β, is defined as the electromagnetic component of the total thrust, T EM , divided by the total thrust. The improvement is primarily a direct result of an increased current density (Amperes per square meter) between the electrodes and a higher peak current. The higher peak current is a direct result of decreasing the plasma resistance between the electrodes and lowering the circuit inductance. The analytical relationship between the instantaneous electromagnetic thrust component, T EM , and time-varying current, I, is:
T EM = ( μ o 4 π ) [ ln ( r a r c ) + C ] I 2 = 1 2 L ′ I 2
where μ o is the permeability of free space, r a is the radius of the annular electrode 124 , r c is the radius of the central electrode 120 , C is a constant that ranges from 0 to 0.75 based on the electrode geometry, and L′ is the inductance gradient (Henries per meter). The analytical relationship between the instantaneous electromagnetic thrust component, T EM , and the plasma resistance is given by
T EM = P ( μ o 4 π ) [ ln ( r a r c ) + C ] R
where P is the instantaneous pulse power and R is the plasma resistance. Notice that the instantaneous electromagnetic thrust is inversely proportional to the plasma resistance, demonstrating the enormous value of any design improvements that reduce plasma resistance.
More specifically, the present invention achieves high system performance through the following: (1) a large electrode radius ratio (r a /r c ) provides high electromagnetic thrust through a high inductance gradient; (2) a central electrode 120 with a conical tip contributes to a high inductance gradient; (3) a conductive conical exhaust section 122 permits the arc to travel from the minimum annular electrode radius outward to a greater radius, providing an average increase in the radius ratio; (4) the geometry of the cavity insulator 130 provides protection against electrode shorting due to carbon deposits on cavity surfaces; (5) the geometry of the propellant 110 within the plasma generating section 112 aids in maintaining a low plasma resistance; (6) a high-capacitance, low internal resistance capacitor 32 reduces current oscillations (ringing) and reduces peak voltage; (7) an annular electrode 124 with significant surface area enables low electrode erosion; (8) a decreased annular electrode erosion permits the use of lightweight metals in its construction, decreasing the overall system mass; (9) a coaxial electrode arrangement with a radial propellant feed system promotes a constant cavity geometry; (10) a nearly constant cavity geometry and a substantially electromagnetic contribution to the thrust enable repeatable pulse-to-pulse performance; (11) an electrically conducting annular electrode resulting in a large annular electrode surface area to create a small average current density at the cavity wall to allow the annular electrode to be constructed from low density materials such as an aluminum alloy.
In a first exemplary embodiment of the present invention, the total mass of the thruster 100 is 298 grams including 70 grams of useable TEFLON propellant. The radius of the central electrode 120 is 3.8 millimeters and the minimum annular electrode radius 127 is 14 millimeters resulting in a ratio, r a /r c , equal to 3.68. The thruster operates typically at energy levels of 40-70 Joules per pulse, an average power level of 85 Watts, and a total capacitance of 82 microfarads. The results of initial testing provided an average thrust of 1.7 milli-Newtons, an average specific impulse, I sp , of 1374 seconds, a thruster efficiency of 14 percent, a total circuit resistance of 15 milli-Ohms and an electromagnetic thrust fraction, β being 66 percent of the total thrust.
In a second exemplary embodiment of the present invention, the total mass of the thruster 100 is 400 grams including 75 grams of useable TEFLON propellant. The total capacitance of the capacitors is 80 microfarads. The thruster operates at 100 Watts with an efficiency of 16 percent and an average I sp of 1350 seconds with a total impulse of 990 Newton-seconds. Testing demonstrated a thrust of approximately 2.0 milli-Newtons where 1.2 milli-Newtons is electromagnetic, resulting in a β of 60 percent.
In both the first and second exemplary embodiments, the thruster proved to have highly repeatable pulse-to-pulse performance. The thrust and peak current both demonstrate less than 2% variation over long durations during initial testing.
From the foregoing and as mentioned above, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the novel concept of the invention. It is to be understood that no limitation with respect to the specific methods and apparatus illustrated herein is intended or should be inferred. | A pulsed plasma thruster provides for an advanced lightweight design with solid propellant and predominately electromagnetic thrust in a coaxial geometry. Electromagnetic forces are generated in a plasma by current flowing from a small central electrode to an electrically conducting diverging nozzle electrode. The thruster employs a series of electric current pulses of limited duration and varying frequency between the pair of electrodes creating a series of electric arcs. The electric arcs pass over a propellant surface located between the electrodes, forming a plasma, which is then exhausted from the device to produce thrust. The thruster maintains a low plasma resistance and cavity pressure, which in turn yields strong electromagnetic body forces, resulting in a high efficiency and consistent pulse-to-pulse performance. | 5 |
FIELD OF THE INVENTION
A Control system and air flow control register for use in a single or multi zone HVAC unit where air is delivered into one or more zones through an air delivery register (s).
BACKGROUND OF THE INVENTION
It has been long recognized in large building structures that the cost of heating or cooling the structure significantly impacts the bottom line of the large business enterprise that occupy these structures. It is also know that for a small business entities such as a clinic, office or retail structure total energy costs related to lighting, heating or cooling breaks down this way: 40% is for heating and cooling, 40% for lighting and the balance for business related equipment. The U.S. Department of Energy estimates that a substantial portion of the heating, cooling and lighting cost is wasted as a result of the lack of an economical, effective system to control it.
In the design stage of large business structures elaborate lighting heating and cooling systems are built into the structures at the outset with an expectation that significant energy savings translated into dollars will be realized for the businesses occupying these structures. In the smaller business building market almost all heating and ventilation systems employ a single zone HVAC unit to supply conditioned, heated or cool air to more than one distinct zone or room. Each room or zone may have different comfort requirements due to occupancy differences, individual preferences, exterior load differences or the different zones may be on different levels, thereby creating different heating or cooling requirements. This type of system is referred to a single zone HVAC unit because it is normally controlled from one centrally located ON/OFF thermostat controller. In a building which may have more than one zone and whose zones have different heating, cooling requirements, it becomes difficult to choose a good representative location for the thermostat controller.
In the technical literature which embrace patented technologies there have been a number of note worthy attempts to provide systems that address the problems of controlling the different needs of more than one zone which is provided heating and cooling from a single zone HVAC.
Among the most recent U.S. Patents is that of Brian Hampton U.S. Pat. No. 5,271,558 ('558) titled Remotely Controlled Electrically Activated Air flow control register. The '558 patent is assigned to the same assignee as that of the instant application. Many of the circuit details setforth in the subject application were originally setforth and fully described in the '558 patent. No claims of novelty is put forward with respect to these circuit details per se in this application.
The invention of the '558 Patent is directed to a control system for an air delivery system having a supply duct through which air is delivered into at least one independently controlled zone though an air delivery register. A wireless airflow control unit is provided to transmit a wireless airflow control signal output to an electrically powered and electrically self-sufficient flow control unit located in at the air delivery system. The electrically powered and electrically self-sufficient flow control unit controls the flow of the air in response to receiving the wireless air flow control signal output. The electrically powered and electrically self sufficient flow control unit includes a generator to provide electrical power in response to flow of air from the supply duct. The generated electric power is delivered to the flow control unit to thereby maintain the flow control unit electrically self-sufficient and free from the need of any outside electrical power source. The generator includes a rotary mounted turbine positioned within a supply duct of the air delivery register. The Turbine is coupled to the generator to drive the generator in response to conditioned air flow against blades of the turbine. The generator provides electric power to the flow control unit to maintain the flow control unit electrically self sufficient. The air delivery system is a normally single zone HVAC unit. The flow control unit includes a HVAC temperature detection unit that determines when the HVAC unit is delivering heated, cooled conditioned air or recirculating ambient air. The HVAC temperature detection unit has an output signal to a logic unit. The logic unit is also responsive to a wireless airflow control signal. The flow control unit additionally includes a turbine/generator load control unit coupled electrically to receive an output signal from the logic unit. The logic unit output signal controls a loading of the generator so that the air turbine is braked thereby reducing flow of conditioned air past the air turbine and into a Zone.
The invention of the '558 patent has proved to be popular especially where there is present a high level of concern for maximizing electrical energy savings. The subject invention, however, has proved equally popular in environments where low voltage D.C. power may be employed to power the electronics mounted in the register and to power a D.C. or A.C. motor to drive a turbine as a fan in such a manner as to provide air pressure that opposes the normal air flow in the air delivery system, thereby controlling conditioned air flow through the register in a zone.
Another such U.S. patent is that of Tate et al U.S. Pat. No. 4,969,508 (508) in which the temperatures in the room(s) are controlled by means of a wireless portable remote control unit which may be hand held by the room occupant. The wireless remote control unit transmits information to a remote receiver in the ceiling of the room, which in turn provided signals to a main control unit physically coupled to external environmental control units such as the air conditioning system, heater, damper motors and the like.
The wireless remote control unit of the '508 patent in addition to being able to select heating and cooling modes may also operate in an energy saving mode. To this end a light sensing circuit is provided for overriding preselected conditions when the lights in the room are off. An infra red transmitter is employed for transmitting data to an infra red receiving unit on the ceiling when the lights are on.
The subject invention distinguishes over the '508 patent in that the '508 patent requires wiring of an entire duct work system to provide power to many power driven dampers, whereas the subject invention simply calls for an A.C. or D.C. power converter in each room or zone to be controlled. The subject invention additionally provides a low D.C. voltage source at the register to power the electronics associated with the control of the register.
Another approach to providing multiple heating/cooling zones which employ a single zone HVAC unit is shown and described in the Parker et al U.S. Pat. No. 4,530,395 ('395) U.S. patent. The Parker et al arrangement provides zone control in plural zones in which each zone includes a control thermostat that is interfaced with a monitoring system so that each zone thermostat controls the HVAC unit as well as a damper unit for that particular zone. More specifically the system is comprised of two or more computerized thermostats which control both the HVAC unit through the monitoring control and the air distribution system of each zone through the damper for each zone. The thermostats also operate under control of signals received from the monitor.
The '395 is classic in its complex solution to the very simple concern of independently and automatically controlling the temperature in one of many zones simultaneously. The '395 patent like the '508 just reviewed requires electrically powered damper motors that become part of a complex wiring system.
The subject invention requires no such complex wiring and may be readily installed in existing HVAC system by simply removing a selected air distribution register and placing within an exposed air supply duct the apparatus of the instant invention, which is then electrically connected to an existing electrical system by means of an A.C. to D.C. converter.
A wireless thermostat control device hung on a wall of a zone wall completes the installation of the subject invention in almost no time at all with little labor cost.
In yet another multiple zone system having a single central HVAC unit Robert S. Didier in his U.S. Pat. No. 4,479,604 ('604) shows and describes a controller for a central plant feeding a plurality of adjustable zone regulators which bring their respective zones to corresponding target temperatures. The controller has a plurality of temperature sensors and a plurality of zone actuators. The temperature sensors distributed one to a zone, each produce a zone signal signifying zone temperature. The zone actuators each have a zone control terminal. Each actuator can, in response to a signal at its zone control terminal, operate to adjust a corresponding one of the zone regulators. The controller also has a control means coupled to each of the temperature sensors and to the zone control terminal of each zone actuator for starting the central plant. The central plant is started in response to a predetermined function of zone temperature errors (with respect to their respective target temperatures) exceeding a given limit. The systems considers the temperature error in each of the zones. When the sum of the errors exceeds a given number, the furnace or air conditioner can be started.
In addition to the distinctions offered in respect of the '508 and '395 patents the subject invention is amazingly simple in design and may be powered by a D.C. voltage power source at a zone to be controlled thereby obviating the need for a complex wiring system inherent in the '604 patent.
SUMMARY OF THE INVENTION
The invention is directed to a method and apparatus for controlling airflow in a given direction in an air circulating system in which the method comprises the steps of:
(a) placing a motor driven fan in the air circulating system in such a manner that the fan, when driven by the motor, creates pressure in a direction opposing the given direction of airflow, and
(b) activating the motor to drive the fan to cause the airflow moving in said given direction to be diminished because of said opposing pressure.
More specifically, the invention is directed to an air flow controllable register for controlling a flow of air through the register from a register air flow supply duct in response to an externally provided control signal that commands differing airflow rates through the register. More specifically, the air flow controllable register includes a register flow control unit that includes a rotary mounted fan positioned within the register airflow supply duct. The fan is coupled to a motor. The fan when driven by the energized motor creates air pressure from the fan to reduce the flow of air from the supply duct.
The register flow control unit is responsive to the externally provided control signal to provide for the energizing of the motor coupled to the fan to provide air pressure against the flow of air from the supply duct thereby simultaneously diminishing air flow past the fan and through the register.
It is therefore a primary object of the invention to provide a method and apparatus for controlling airflow in a given direction in an air circulating system.
It is also a major object of the invention to provide an electrically controlled automatically adjustable air flow register.
Another object of the invention is to provide an air circulating system that controls air flow in a given direction in the system by introducing an opposing pressure to thereby diminish air flow past a point in the system where the opposing pressure has been introduced.
A further object of the invention is to provide an automatically adjustable airflow register that when added to an existing system has minimal affect on air flow when a free flow of air through the register is desired.
Yet another object of the invention is to provide a method of controlling air flow in a system by employing a motor driven fan positioned in the system in such a manner that when the motor is activated or energized the fan rotates in a direction such that a pressure is provided which opposes normal airflow in the system thereby controlling system airflow.
In the attainment of the foregoing objects the invention contemplates as falling with the purview of the claims a control system for an air delivery system which is normally a single zone HVAC unit. The air delivery system includes a single air supply duct through which conditioned air is delivered. The control system assumes that there is at least one independently controlled zone or room which received air delivered through an air delivery register.
The control system includes two basic components one of which is an air flow thermostat control that communicates with and controls an electrically powered register flow control unit which controls the flow of conditioned air through the air delivery register.
A typical system involves a plurality of zones each zone having one or more air delivery registers, each of which is coupled to the single air supply duct noted earlier.
The air flow control thermostat delivers an airflow control signal which is characterized as a continuously transmitted control signal for as long as a desired setpoint temperature for an associated zone is either above or below an ambient temperature in the associated zone.
The electrically powered register flow control unit controls the flow of air through the register in response to receiving the flow control signal. This just noted register flow control unit includes a motor driven fan within a register supply duct associated with an air delivery register. The motor driven fan is positioned in such a manner that, when energized, the fan rotates so as to provide an opposing air pressure to that which normally passes through the register. This opposing pressure diminishes the amount of air flow passing the fan thereby controlling the air flow through the register into a zone.
In systems where both heating and cooling unit are provided the register flow control unit also includes an HVAC temperature detector to determine whether the HVAC unit is delivering heated or cooled air. The HVAC temperature detector has an output signal to a logic circuit representative of either heating or cooling by the HVAC.
In a preferred embodiment of the invention the register flow control unit includes an airflow control signal detection circuit electrically coupled to a decoding circuit to provide an output signal from the decoding circuit to the logic circuit representative of whether an ambient temperature in a zone associated with the register flow control unit is greater than a desired setpoint temperature of the zone or whether the decoding circuit output is representative of the fact that the ambient temperature in the zone is less than or equal to the desired setpoint temperature in the zone.
Finally the logic circuit provides the output signal which controls the energization of the motor driven fan whenever a preselected combination of output signals from the HVAC temperature detection circuit and decoding circuit call for decrease air flow through the air delivery register.
In less technical terms and by way of summary, assume that it is summer, during the cooling season and the air conditioning has just come on in an office building. In the cooling operation, cooled air flows down the air supply duct through the flow control unit and out an air delivery register. As the cool air flows down the air supply duct through the register flow control unit the flow of air turns the fan in a free wheeling manner such that little restriction to air flow through the register is present. This operation will continue until the flow control thermostat has determined that the desired temperature level has been reached. Now that the room or zone is cool enough and further amounts of air are not only unnecessary, but waste costly energy, the system responds by having the flow control thermostat signal electronic controls in the register flow control unit to restrict further air flow by energizing the motor driven fan to provide an opposing air pressure to normal system flow at the register.
From the foregoing it will be readily appreciated that the opposing airpressure will result in a significantly reduced air flow from the register flow control unit through the air delivery register.
The increase in back pressure at a single register in a multiple register system will cause an increase in flow from other registers in the system. This accelerates the cooling in the other offices or zones. As each of them reaches a comfort set point selected by an office user, the register air flow control unit will reduce air flow to that office.
The result of restricting air flow to each office or room in this manner provides not only a substantial increase in comfort, but the achievement of comfort levels more quickly than the standard on/off method so that the air conditioning unit can be shut down sooner saving energy cost.
Use of the invention also reduces the flow from the supply system which reduces the energy required to drive the supply system.
BRIEF DESCRIPTION OF THE DRAWINGS
The description setforth above, as well as other objects, features and advantages of the present invention, will be more fully appreciated by referring to the detailed description and the drawings that follow. The description is of the presently preferred but, nonetheless, illustrative embodiment in accordance with the present invention, when taken in conjunction with the accompanying drawing wherein;
FIG. 1 is a schematic layout of an office complex with a number of zones to be heated or cooled by employing the invention described herein;
FIG. 2 shows in cross section a portion of the air flow control system that embodies the invention where the invention is depicted in a free-wheeling mode;
FIG. 3 shows in cross section a portion of the air flow control system that embodies the invention where the invention is depicted in an air flow opposing mode;
FIG. 4 is a block diagram illustration of an air control system, that embodies the invention;
FIG. 5 is a logic unit block diagram:
FIG. 6 is a schematic showing of the relationship of the components present in a wireless flow control thermostat employed in the invention, and
FIG. 7 is a schematic showing of the relationship of the components present in a register flow control unit embodying the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference is now made to FIG. 1 which illustrates schematically an office complex in a building not shown. The office complex includes two (2) zones to be provided with forced hot or cooled air from a HVAC (heating, ventilating, air conditioning) unit 15. Zone #1 is defined by a pair of side walls, 20 and 21, a ceiling 22 and floor 23. A fourth side wall is present, but not shown. Accordingly zone #1 is one of many office/rooms in the office complex. Zone #2 is similar in overall configuration as zone #1.
The zone #1 includes a wall mounted wireless air flow control thermostat (30, 31) to be described more fully hereinafter with respect to FIG. 6. It is to be understood that while the preferred embodiment of the invention shows the use of a wireless infra red (IR) controlled thermostat. The invention is equally useful with a wide range of different types of thermostats of a wireless or hard wired nature. Zone 2 is provided with a conventional ON/OFF thermostat 32 electrically coupled via an electrical line 16 to HVAC controller 17. Electrical power is provided to the wireless air flow control thermostat 30 from an AC power supply 40 via electrical line 41. Line 41 leads to a wall outlet 42 which has schematically shown a zone manager power supply 43 to provide electrical power via line 44 to wireless air flow control thermostat 30. Wireless airflow control signals 53, 54 depicted as jagged separated lines are shown directed toward an air diffuser portion 61 of air delivery register 60. The HVAC 15 delivers conditioned air to zone #1 via a single air supply duct 18 and a branch air supply duct 18a. Positioned in the branch air supply duct 18a, as shown in FIG. 2 and FIG. 3, are the electrically powered register flow control unit 70 of the instant invention.
In order to appreciate how the register flow control unit 70 operates, one of the units 70 is shown in FIG. 2 in partial section in a free wheeling mode and in partial section in FIG. 3 in an airpressure opposing mode.
Turning now to FIG. 2 there is shown an end portion of the single air supply duct 18 with a branch air supply duct 18a secured thereto by means not shown. An air diffuser portion 61 which forms a major part of the air diffuser register 60 is secured to the branch air supply duct 18a by conventional means not shown. An electrically powered register flow control unit 70 is shown in position to demonstrate the manner in which air flow, indicated by air flow arrows 72 and 73, pass by the register flow control unit when a fan 80 is in a freewheeling mode.
In FIG. 3 an arrow 70 points towards the electrically powered register flow control unit. The register flow control unit is made up of two major elements, the first of which is an electronic control box 75 that is electrically coupled via leads not shown to an input of a D.C. motor not shown but mounted within a rotatable supported air turbine hub 82. The hub 82 also forms the rotor of the DC motor. The motor could also be an AC motor. The operation of the electronic circuitry in the electronic control box 75 which is secured to a structural member not shown of the air delivery register 60 will be described when the operation of FIG. 4 is reviewed.
When FIG. 3, 4 and 5 are studied together the operation and air passage reduction function of the fan 80 and motor contained in air turbine hub 82 will become apparent. In FIG. 3 there is shown fitted in branch air supply duct 18a the fan 80 and its hub 82 which contains a motor and which may be secured to the duct 18a by conventional means not shown. Secured to the turbine hub 82 are fan impeller blades. Only two (2) fan blades 85, and 86 are shown. It is to be understood the number of fan blades is a matter of design and may number more than two.
Reference is now made to FIG. 4 which depicts in schematic form the basic components of a control system for an air delivery system embodying the invention. On the left, as FIG. 4 is viewed, is wireless air flow control thermostat 30, which includes conventional set temperature readout 33; manually operable temperature increase and decrease select buttons 34, 35; heating or cooling select button 36, and infra red (IR) transmitter 37. The register flow control unit 100 which is electrically powered and is electrically self-sufficient is shown schematically in FIG. 4 on the right side of the drawing. A detailed layout of the register flow control unit 100 is shown in FIG. 7 and will be described in detail hereinafter. It is sufficient to note at this point that the register flow control unit 100 includes, interconnected as shown, four (4) basic functional components, namely an HVAC temperature detection circuit or unit 110; a wireless air flow control signal detection and decoding unit or circuit 120; a logic unit 150, and an opposing flow turbine control unit 160.
Attention is now directed to FIG. 6 which illustrates in block diagram layout the details of the wireless air flow control thermostat 30 employed in zone #1 of FIG. 1.
In the left hand portion of the drawing of FIG. 6 there is shown in broken away fashion an external portion 29 of the wireless air flow control thermostat 30 described with respect to FIG. 6. Shown in broken line 29 surrounding the block diagram are the essential component parts of the wireless air flow control thermostat 30 which will now be described. The wireless thermostat 30 includes in a conventional manner a zone or room temperature sensor 38 which provides on an output lead 39 a signal representative of the rooms ambient temperature, Tz, at any given moment. The ambient temperature signal on lead 39 is delivered to an operational amplifier 45 which has as another input lead 46 which provides a manually variable, desired zone temperature setpoint (Tzsp). In the situation being described the Tzsp has been selected by the zone #1 occupant at 65 F. The operational amplifier 45 functions in a conventional manner and provides an output lead 47 a low (Lo) output whenever the ambient zone temperature TZ is less than or equal to the zone temperature setpoint TXsp, (Tz<Txsp) here 65 F. and a Hi output whenever the ambient zone temperature Tz is greater than the zone temperature setpoint Tzsp (65 F.), namely Tz>Txsp. The lead 47 is connected as shown to a trigger pulse circuit 48 which responds to produce trigger pulses 49, 50 at the rate of one per minute whenever the output signal on lead 47 from the operational amplifier 45 goes Hi. The trigger pulses 49, 50 appears on lead 51 where they are delivered to a one shot circuit 52 that produces the wave form output 55 on lead 56 whenever and for as long as TZ>Tzsp. The wave form output 55 appears on lead 56 where it triggers the thermostat infrared (IR) transmitter 36 to provide the wireless IR signals 53, 54 to the register flow control unit 100 not shown in this figure. A carrier frequency source 59 of 39 KHZ modulates the IR signal output over lead 59a to provide the wave from 53, 54 shown below as jagged line IR signals 53, 54. It should be apparent that when the temperature in the zone Tz is less than or equal to the zone temperature setpoint Txsp ie 65 F. there will be no IR transmitter 36 output.
Attention is now directed to FIG. 7 which illustrates in a schematic block diagram form the internal workings of the register flow control unit 100 shown in broken line. At the left hand side of the drawings of FIG. 7 there is shown in broken line an HVAC temperature detection unit or circuit 110. This HVAC temperature detection circuit 110 includes two major components, namely, an air duct discharge sensor 101 and to an operational amplifier 103 via a lead 102. The sensor 101 and operational amplifier 103 are conventional in nature. The air duct discharge sensor 101 is positioned in the system so that conditioned discharge air flowing form the main supply duct 18 via duct branch the heating or air cooling mode. The temperature of 70 F. has been selected as a reference point. Whenever the air coming from HVAC unit 15 through ducts 18 and 18a is above 70 F., this condition will be considered to be a heating mode, whereas if the temperature of the air from the HVAC is below 70 F. the system will be considered to be its cooling mode. Accordingly, the operational amplifier 103 is designed to provide a Lo output on Lead 105 indicating the HVAC as operating in a heating mode. The Hi or Lo outputs on lead 105 are delivered to logic unit 105, the function of which will be described hereafter.
Just beneath the HVAC temperature detection unit 110, also shown setout in broken line, is the wireless air flow control signal detection and decoding unit or circuit 120. The basic functions of this just noted unit 120 are to receive ie detect the wireless IR signals 53, 54 from the wireless air flow control thermostat 30 and decode the transmitted information from the wireless air flow control thermostat transmitter 36.
The wireless IR signals 53, 54 are received by infrared (IR) receiver 121 which in turn provides a signal out on lead 122 representative of an envelope 123 of the signals 53, 54. The possible output signals on lead 122 are shown for the conditions Tz>Tzsp which represents zone ambient temperature greater than zone temperature setpoint which had been arbitrarily set at 65 F. for purposes of explaining the air flow control system operation.
The just described output on lead 122 is delivered to timeout/reset circuit (TORCKT) 123 which provides an output on lead 124 to the logic unit 150. The TORCKT 123 is designed to provide a low (Lo) output on lead 124 when the IR pulses are representative of the condition Tz<Tzsp and a Hi output on lead 124 when the IR pulses are not present on the lead 122 to the TORCKT 123 for 5 minutes. When this state is present the output on lead 124 goes Hi indicating that TZ<Tzsp.
Located on the lower right hand corner of the drawing of FIG. 7 is the opposing flow fan control unit 160 shown in broken line. Direct current is provided on leads 75, 76 from a power supply not shown. The power supply may use conventional AC to DC converter that provides 24 volt DC over leads 75, 76 via the front relay contact 152a of a latching relay 152 to DC motor driven turbine 80.
The logic unit 150 has a single output on lead 151 which is electrically connected to a latching relay 152 which when energized goes from a normally closed (NC) electrical contact position to a normally open (NO) electrical contact position. When the latching relay 152 is activated an electrical circuit is completed across the DC motor driven turbine 8 and DC power supply 141 via leads 75, relay contact 152a, lead 77 and lead 76. This results in the energizing of the DC motor driven turbine 80 which results in the DC motor driven turbine providing a flow of air that opposes the normal flow of air through the register. This results in a significantly reduced air flow through the register air flow control unit 100 and the air delivery register 60 in particular.
It should be understood that the invention contemplates as included with in the language of the claims solid state electronic devices in place of for example the latching relay 152.
An understanding of the full operation of air control system is readily discernable when the "Logic Unit" of FIG. 5 is studied in conjunction with the earlier described units and circuits.
In accordance with the primary object of the invention to provide a method and apparatus for controlling airflow in a given direction in an air circulating system, it follows that while in the preferred embodiment of the invention the powered flow control unit is shown in a register, the powered flow control unit maybe positioned anywhere in the system to provide an airflow damping function in accordance with the invention.
Though the invention has been described with respect to as specific preferred embodiment thereof, many variations and modifications will immediately become apparent to those skilled in the art. It is therefore the intention that the appended claims be interpreted as broadly as possible in view of the prior art to include all such variations and modifications. | The invention is directed to a method and apparatus for controlling airflow in a given direction in an air circulating system in which the method comprises the steps of:
(a) placing a motor driven fan in the air circulating system in such a manner that the fan, when driven by the motor, creates pressure in a direction opposing the given direction of airflow, and
(b) activating the motor to drive the fan to cause the airflow moving in said given direction to be diminished because of said opposing pressure.
The apparatus is directed to an air flow controllable register for controlling a flow of air through the register from a register air flow supply duct in response to an externally provided control signal that commands differing airflow rates through the register. More specifically, the air flow controllable register includes a register flow control unit that includes a rotary mounted fan positioned within the register airflow supply duct. The fan is coupled to a motor. The fan when driven by the energized motor creates air pressure from the fan to reduce the flow of air from the supply duct. | 5 |
BACKGROUND OF THE INVENTION
The field of invention relates to the ultrashort-pulse lasers (femtosecond regime). More precisely, the invention relates to a femtosecond (fs) pulsed laser, characterized by a carrier frequency and by an envelope frequency. Still more precisely, the invention relates to a mean for stabilizing the phase drift between the carrier frequency and the envelope frequency of a train of femtosecond laser pulses.
DESCRIPTION OF THE RELATED ART
Since around twenty years, the research and development of short-pulse lasers have known a significant progress. The pulse durations obtained belong at the present time to the femtosecond domain. In parallel, the development of the technique of chirped pulse amplification (D. Strickland, G. Mourou “Compression of amplified chirped optical pulses” Optics communications, vol. 55, issue 6, 15 Oct. 1985, p. 447-449 & Optics communications, vol. 56, issue 3, 1 Dec. 1985, p 219-221) has allowed reaching very high peak powers, of the order of the petaWatt.
One of the research axes about this type of sources relates to the so-called phenomenon of phase drift between envelope and carrier, schematically illustrated in FIG. 1 . A light wave coming from a laser is an electromagnetic wave whose electric field may be represented by the product of a wave at a given frequency, the carrier wave ( 50 ), by an envelope function ( 60 ). The frequency of the carrier wave ( 50 ) is directly linked to the wavelength of the laser, whereas the envelope ( 60 ) allows characterizing the duration of the pulses and the pulse repetition frequency (f rep ). The speed of propagation of the envelope ( 60 ) is called the group velocity and corresponds to the speed of propagation of the energy. That of the carrier frequency ( 50 ) is called the phase velocity. In a dispersive medium, the group and phase velocities are generally different from each other, which may induce a time drift of the carrier oscillation inside the envelope (cf. FIG. 1 ).
For relatively “long” pulse durations, i.e. for example of the order of the nanosecond, each pulse contains a very high number of optical cycles (of the order of 3.10 5 cycles in the visible spectrum), and the drift between the frequency of the carrier and the frequency of the envelope has no notable consequence. In the case of the ultrashort-laser pulses, the number of optical cycles is on the contrary not much high (cf. FIG. 1 ) and the time position of the carrier in the envelope may have significant consequences on certain physical phenomena which are sensitive to the electric field and not to the field envelope (A. Baltuska et al. “Attosecond control of electronic processes by intense light fields” Nature 421-2003).
If the maximum of the electric field coincides with the position of the maximum of the envelope for a given pulse, this may be no longer the case at the following pulse. This time shift corresponds to a phase shift Δφ of the carrier and it is also designated by the acronym CEP (Carrier Envelope Phase). The phase shift Δφ may vary in time according to the occurrence of perturbations of various origins on the optical path of the laser (vibrations, variations of refractive index of the materials . . . ). The variations of the phase shift Δφ, i.e. the CEP variations, as a function of time are called “phase drift between envelope frequency and carrier frequency”. This is illustrated for example in the publication of Nisoli et al., which describes the measurement of the random variations of CEP, shot by shot, for pulses of duration comprised between 5 and 7 fs (“Effects of Carrier-Envelope Phase Differences of Few-Optical-Cycle Light Pulses in Single-Shot High-Order-Harmonic Spectra” Phys. Rev. Letters, Vol. 91, n° 21, 2003). Another example is described in the publication of Z. Chang (“Carrier-envelope phase shift caused by grating-based stretchers and compressors” Applied Optics, vol. 45, n° 32, 2006) in which the influence of a diffraction-grating-based stretcher or compressor on the CEP drift is evaluated.
The technique problem that is considered herein generally relates to the stabilization and the control of the phase drift between envelope frequency and carrier frequency of ultrashort laser pulses.
Apart from the particular case of the optical parametric oscillators which, in certain specific conditions (A. Baltuska et al. “Controlling the Carrier-Envelope Phase of Ultrashort Light Pulses with Optical Parametric Amplifiers” Physical Review Letters, Vol. 88, n° 13, 1 Apr. 2002), allow freeing elegantly from the CEP drifts, various techniques of correction of the CEP exist, which are based on a slow feedback loop containing a f-2f interferometer (Kakehata et al. “Measurements of carrier-envelope phase changes of 100-Hz amplified laser pulses” Applied Physics B. 74, S43-S50 2002). They can be grouped into two categories.
The first one relates to the mode-locked oscillators and the correction is made by acting on certain parameters of the cavity (Jones et al. “Carrier Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis” Science 288,635,2000). Let's note that this method does not allow, with a single control loop, to correct the possible fluctuations of CEP downstream of the cavity, linked for example to perturbations on the subsequent path of the laser beam.
The second category, which supposes a previous stabilization of the oscillator, corresponds to corrections made downstream of the latter, generally before the amplification. Among the main techniques used, it may be mentioned:
the use of a pair of prismatic plates in a dispersive material. The mechanical displacement of the plates allows modifying the CEP (C. Grebing et al., “Isochronic and isodispersive carrier-envelope phase-shift compensators”, Applied Physics B 97, p. 575-581, 2009). However, the necessity of a mechanical movement allows only a correction of the relatively slow phase drift; the modification of a parameter of the compressor or of the stretcher, wherein this parameter can be the distance between two gratings or between two prisms (Chang, “Carrier-envelope phase shift caused by grating-based stretchers and compressors” Applied Optics, vol. 45, n° 32, 2006, p. 8350-8353). Here again, the necessity of a mechanical movement of interferometric precision limits the speed of the device. the use of an acousto-optic programmable dispersive filter (OAPDF) (P. Tournois “Acousto-optic programmable dispersive filter for adaptive compensation of group delay time dispersion in laser systems” Optics communications 140 245-249 (1997)). Such an acousto-optic dispersive filter allows inducing a programmable phase shift with a fast response time (kHz) but the cost of such a device is high; the use of a 4f system with a liquid crystal matrix (Spatial Light Modulator) (M. Kakehata et al. “Use of a 4f pulse shaper as an active carrier-envelope phase shifter” Conference paper, CLEO 2004, CTuP, CTuP31). The response time is important and does not allow correcting the CEP drift, shot by shot.
SUMMARY OF THE INVENTION
One of the objects of the invention is to provide a device and a method of stabilization of the CEP that is applicable to the high-energy chirped pulse amplification lasers operating at high repetition frequencies (of the order of the kHz to the MHz) and of reduced cost.
In the present document, it is meant by “high-energy laser pulses” laser pulses having an energy higher than the nanojoule.
More precisely, the invention relates to a high-energy femtosecond pulsed laser, stabilized as regards the phase drift between envelope frequency and carrier frequency, said laser comprising a source of laser pulses to be amplified, said source being adapted to generate a train of input laser pulses having an envelope frequency and a carrier frequency, chirped pulse amplification means comprising stretching means adapted to time stretch the input laser pulses, optical amplification means adapted to amplify the stretched laser pulses and compression means adapted to time compress the amplified laser pulses, and means for controlling the phase drift between envelope frequency and carrier frequency of the output laser pulses. According to the invention, said means for controlling the phase drift between envelope frequency and carrier frequency comprise electro-optical modulation means placed on an optical path of the laser pulses so as to stabilize the phase drift between envelope frequency and carrier frequency of the output laser pulses as a function of time.
According to a first embodiment of the invention, said electro-optical modulation means comprise a transverse-Pockels-effect electro-optical phase modulator.
According to different particular aspects of the first embodiment of the invention:
the laser further comprises means for angularly orienting the ordinary and/or extraordinary optical axes of said Pockels-effect modulator relative to a direction of polarization of the laser pulses; said Pockels-effect modulator is placed on the optical path of the chirped pulse amplification means.
According to a second embodiment of the invention, said stretching means and/or said compression means comprise at least one prism and said electro-optical modulation means comprise electrodes respectively deposited on faces of said prism and means for applying an electric field to the terminals of said electrodes so as to induce a modulation of the refraction index of said prism.
According to a particular aspect of the second embodiment of the invention, said stretching means and/or said compression means respectively comprise two prisms arranged so as to compensate for a spatial offset of the optical beam and said electro-optical modulation means comprise electrodes respectively deposited on faces of said two prisms and means for applying an electric field to the terminals of the electrodes of the two prisms so as to modulate the refraction index of the two prisms.
According to various particular aspects of the invention,
said electro-optical modulation means have an operating frequency comprised between a few Hz and several MHz; the laser further comprises means for measuring the phasedrift between envelope frequency and carrier frequency of the output laser pulses as a function of time; and/or the laser further comprises a feedback loop so as to adjust the modulation induced by said electro-optical means as a function of the measurement of the phase drift between envelope frequency and carrier frequency.
The invention also relates to a method of stabilization of the phase drift between envelope frequency and carrier frequency of a high-energy (higher to the nanojoule) femtosecond pulsed laser, said method comprising the following steps:
generation of a train of input laser pulses formed of an envelope frequency and a carrier frequency; chirped pulse amplification of said input laser pulses comprising a step of time stretching of said input laser pulses, a step of optical amplification of said stretched laser pulses and a step of time compression of said stretched and amplified laser pulses, and said step of chirped pulse amplification comprising a step of stabilization of the phase drift between envelope frequency and carrier frequency of the output laser pluses.
According to the method of the invention, said step of stabilization of the phase drift between envelope frequency and carrier frequency comprises an electro-optical modulation of an optical component so as to stabilize the phase drift between envelope frequency and carrier frequency of the output laser pulses as a function of time.
According to a particular aspect of the method of the invention, said method further comprises:
a step of measurement of the phase drift between envelope frequency and carrier frequency of the output laser pulses as a function of time, and a step of adjustment of the feedback electro-optical phase modulation as a function of said measurement of the phase drift between envelope frequency and carrier frequency.
The present invention also relates to the features that will become evident from the following description and that will have to be considered either alone or in any technically possible combination thereof.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
This description, which is given by way of non-limitative example, will allow a better understanding of how the invention can be implemented, with reference to the appended drawings in which:
FIG. 1 schematically shows an electromagnetic wave defined by a carrier frequency and an envelope frequency;
FIG. 2 schematically shows the first configuration used (spectral interferometry) for revealing the CEP correction according to a first embodiment of the invention;
FIG. 3 shows an example of fringes observed by spectral interferometry, in presence of a voltage applied to the LiNbO 3 crystal (V=240 Volt) and without voltage;
FIG. 4 shows the CEP variation measured by spectral interferometry as a function of the voltage applied to the crystal;
FIG. 5 schematically shows a chirped pulse amplification laser device used for revealing the CEP correction according to a first embodiment of the invention;
FIG. 6 shows shot-by-shot measurements of the CEP response of an electro-optical modulator used in an embodiment of the invention;
FIG. 7 shows measurements of interference fringes by f-2f interferometry for various forms of voltage modulations applied to an electro-optical modulator, a sinusoidal voltage ( FIG. 7A ), a saw-toothed voltage ( FIG. 7B ), a rectangular-shaped voltage ( FIG. 7C ), respectively;
FIG. 8 shows various curves of CEP measurement as a function of various modulation frequencies;
FIG. 9A schematically shows a CEP modulation device according to a second embodiment of the invention and FIG. 9B schematically shows a perspective view of a prism used in the second embodiment.
DETAILED DESCRIPTION OF THE INVENTION
First Embodiment
The first embodiment is based on the modulation of the CEP of optical pulses by means of using only one optoelectronic component. More precisely, the first embodiment is based on the use of a modulator of the electro-optical type, the principle of which will be detailed hereinafter. Let's consider a laser pulse propagating in a dispersive optical element. The phase time T φ and the group delay time T g are defined by the following equations (1.a) and (1.b), respectively:
T
φ
=
n
(
ω
0
)
·
L
c
(
1.
a
.
)
T
g
=
n
g
(
ω
0
)
·
L
c
(
1.
b
)
where c represents the velocity of light in vacuum, L the length traveled by the optical beam in the dispersive element, ω 0 is the central (angular) frequency of the laser, n(ω 0 ) and n g (ω 0 ) being the refraction index and the group index, respectively, on the medium at the frequency ω 0 .
The delay induced by the difference between the group velocity and the phase velocity may thus be written according to the equation (2):
T
g
-
T
φ
=
[
n
g
(
ω
0
)
-
n
(
ω
0
)
]
L
c
(
2
)
The group index n g is linked to the module of the wave vector k
[ k = n ω c ]
by the relation (3a):
n
g
(
ω
0
)
c
=
∂
k
∂
ω
|
ω
0
(
3
a
)
which allows expressing the group index as a function of the refraction index and of the wavelength λ 0 :
n
g
(
ω
0
)
=
n
(
λ
0
)
-
λ
0
∂
n
∂
λ
|
λ
0
(
3
b
)
The equation (2) may thus be expressed as the equation (4):
T
g
-
T
φ
=
-
λ
0
·
∂
n
∂
λ
|
λ
0
·
L
c
(
4
)
An electric field E applied to a medium generates a transverse-Pockels-effect variation of the refraction index. Herein is considered an optical pulse propagating for example in a lithium niobate (LiNbO 3 ) crystal in the direction Oz. However, the same principle is applicable to other non-linear crystals presenting the Pockels effect, as the RTP, the KTA, etc. . . . The laser field is supposed to be linearly polarized in the direction Ox, just as the electric field applied, and the axis Ox corresponds to the extraordinary axis. The electric field applied is thus transverse to the propagation axis of the pulse beam. The ordinary n 0 and extraordinary n e indices are then given as a function of the electric field E and of the electro-optical tensor elements r 13 and r 33 by the following relations:
n
0
(
E
)
=
n
0
-
1
2
·
n
0
3
·
r
13
·
E
(
5.1
)
n
e
(
E
)
=
n
e
-
1
2
·
n
e
3
·
r
33
·
E
(
5.2
.
)
The use of the relation (5.2) thus gives the variation of the delay (induced by the deviation between group and phase velocities) when the electric field is applied:
(
T
g
-
T
φ
)
[
E
]
-
(
T
g
-
T
φ
)
[
E
=
0
]
=
λ
0
[
3
2
n
e
2
(
λ
0
)
·
r
33
(
λ
0
)
·
∂
n
e
∂
λ
|
λ
0
+
n
e
3
(
λ
0
)
2
∂
r
33
∂
λ
|
λ
0
]
E
·
L
c
(
6
)
This finally allows writing the CEP variation in the following form:
Δ
φ
CEP
=
ω
0
·
λ
0
[
3.
2
·
n
e
2
(
λ
0
)
·
r
33
(
λ
0
)
·
∂
n
e
∂
λ
|
λ
0
+
n
e
3
(
λ
0
)
2
∂
r
33
∂
λ
|
λ
0
]
·
E
·
L
c
(
7
)
The phase drift between envelope frequency and carrier frequency Δφ CEP is thus a linear function of the electric field E applied to the terminals of the electro-optical modulator.
By applying an adequate voltage to such a modulator, it is therefore possible to correct the CEP variation of an ultrashort pulse laser. If this device is associated with a feedback loop, it is possible to control the CEP.
Experimental CEP Control Device
Two different experimental devices have been used to test the performances of a transverse-Pockels electro-optical modulator consisted, for example, of a lithium niobate (LiNbO 3 ) crystal. A goldplating is performed on the faces of the crystal in the direction Oy, according to which the voltage may be applied. The laser radiation is polarized linearly according to the direction Ox.
First Device
The demonstration is based on spectral interferometry measurements. A wide-frequency-spectrum laser ( 11 ), such as for example the commercial model “SuperK™ Compact” marketed by “NKT photonics”. This laser operates with a repetition rate of 24 kHz, the emitted radiation spectrum extends from 600 to 900 nm, the duration of the pulses is of the order of the ns and the mean power delivered is of about 100 mW. FIG. 2 shows a laser ( 11 ) coupled to an interferometer of the Mach-Zehnder type, used to measure the variation of the spectral phase of the radiation induced by the lithium niobate crystal ( 5 ) to which is applied an electric field U(t), schematically shown in graph form in FIG. 2 . The electro-optical phase modulator ( 5 ) is inserted in one of the arms of the interferometer and the effects of the phase dispersion of the second order are compensated for in the other arm with a dispersive material of suitable length (the 1-order phase being compensated for via an optical delay line 8 a or 8 b ). After recombination, the beam is sent in a spectrometer that allows a direct access to the CEP variation induced by the modulator.
The voltage applied for a duration of the order of a few hundreds of ms. A membrane ( 7 ) controlled from the voltage generator allows selecting the radiation during two time sequences, wherein one of which corresponds to the timing when the voltage is applied (U(t)≠0) and the other to when it is not applied (U(t)=0). In these conditions, it is possible to record in the exit plane of the spectrometer, and by way of comparison, an image of the interference fringes corresponding to the presence of a voltage (doted-line curve in FIG. 3 ) in superimposition with an image without voltage (full-line curve of FIG. 3 ), as shown for example in FIG. 3 .
By varying the amplitude of the voltage U applied to the crystal ( 5 ) of the transverse-Pockels electro-optical modulator, it may be possible to plot the CEP variation as a function of the electric field. FIG. 4 shows CEP measurements (shown by squares) for different values of electric field applied to the electro-optic modulator as well as a linear regression curve (dash-dot line curve). It may also be determined the coefficient that links the applied voltage to the phase variation that results therefrom.
Second Device
In a second device, the transverse-Pockels electro-optical system ( 5 ) is placed on the path of a chirped pulse amplification laser of the Titanium-Sapphire type, the mode-locked oscillator of which is CEP-stabilized. The CEP variation is measured directly as a function of the electric field applied by means of an internally-developed fast f-2f interferometer allowing shot-by-shot measurements at a frequency higher than the kHz.
FIG. 5 schematically shows the laser system according to this second device. It comprises a mode-locked oscillator ( 1 ), a stretcher ( 2 ), one or several amplification stages ( 3 a , 3 b ) and a compressor ( 4 ). In the example illustrated in FIG. 5 , the stretcher ( 2 ) and the compressor ( 4 ) are based on diffraction gratings ( 21 , 22 , 41 , 42 ). The oscillator ( 1 ) delivers ultrashort pulses ( 10 ) with a repetition rate of the order of 100 MHz, an energy of about 1 nJ and a spectral width of a few tenth of nm. The laser system finally delivers amplified and recompressed pulses ( 40 ) of 2 mJ, whose duration is close to 35 fs. The CEP shot-by-shot residual noise after amplification is of about 320 mrad (over a period of one hour). The electro-optical modulator ( 5 ) is placed between the stretcher ( 2 ) and the regenerative amplifier ( 3 a , 3 b ).
FIG. 6 shows measurements of the shot-by-shot CEP evolution as a function of time. The different steps correspond to different electric voltages (U=−5 kV; U=−2.5 kV; U=+2.5 kV; U=+5 kV; U=3.5 kV) applied to the electro-optical modulator ( 5 ). The dotted line shows the slow CEP drift as a function of time.
This device allows a priori modulating the CEP at a repetition rate higher than the kHz and, to verify this, several voltages have been applied to the crystal as a function of time. FIG. 7 shows the periodic evolution of the CEP observed experimentally via the fringes of the f-2f interferometer, when the voltage applied to the crystal is modulated sinusoidally ( FIG. 7A ), by a saw-toothed signal ( FIG. 7B ) or by a square-wave signal ( FIG. 7C ). These measurements are obtained at the output of a CEP-stabilized chirped pulse amplification TiS chain, using grating-based stretcher and compressor.
FIG. 8 plots the evolution of the CEP imposed by the modulation on the electric field and deduced from fringes observed by the f-2f interferometer. For a better clarity, the phases are offset along the ordinate axis. The full-line curve corresponds to a frequency of the electro-optical modulator of 10 Hz, the dash-line curve to a frequency of 50 Hz, the dash-dot-line curve to a frequency of 100 Hz, and finally the dotted-linecurve to a frequency of 500 Hz. A modulation of the CEP at frequencies going from a few Hertz to several hundreds of Hertz is effectively observed.
Second Embodiment
A second embodiment of the device of the invention is based on the use of a prism compressor and on the modification of the refraction index of the prisms of a compressor by an electro-optical effect for the control of the CEP.
Let's consider for example a prism compressor in a double-path configuration, as schematically shown in FIG. 9A . The compressor ( 4 ) comprises a first prism ( 43 ), a second prism ( 44 ) and a mirror ( 45 ). An input pulse ( 30 ) is schematically shown by a full line transverse to the axis of the optical beam. A separating line ( 6 ) allows separating the incident beam from the output beam of the compressor. In a manner known per se, the first prism ( 43 ) spatially scatters the input pulse as a function of the wavelengths present in the pulse spectrum. At the exit of the first prism, three spatially-separated beams (λ 1 , λ 2 and λ 3 , respectively) have been shown. The second prism ( 44 ) also induces a dispersion of the beams. After reflection on the mirror ( 45 ) and passing back through the second prism ( 44 ) and the first prism ( 43 ), the three beams (λ 1 , λ 2 and λ 3 ) are spatially recombined together, but with a time offset, because they have not followed the same optical path. The output pulse ( 40 ) may then be time compressed according to the scattering of the input pulses ( 30 ).
Electrodes are formed by deposition of a metallic layer ( 43 a , 43 b , 44 a , 44 b ) on the opposite faces of the prism ( 43 and/or 44 ) (cf. FIG. 9B ). The electric field applied between the electrodes is then transverse to the axis of propagation of the pulse beam. It is then possible (via the application of an electric voltage) to modulate by electro-optical effect the refraction index of the prism ( 43 and/or 44 ) and then to modulate the dispersion introduced by the compressor ( 4 ). By applying the same electric voltage on the two prisms ( 43 and 44 ), the system remains fully symmetrical and induces no variation on the pointing of the laser beam. Using four prisms (each of the preceding prisms being then composed of two prisms) and by shifting in the height direction the round trip path of the beam in the compressor, the electric voltage applied on each of the prisms may then be divided by two, for a same phase-shift effect.
The calculations of the variation of the difference between the phase delay and the group delay as a function of the electric field applied show that this method effectively allows the control of the CEP.
The invention proposes several embodiments of simple and relatively cheap devices for fast correction of the CEP, applicable in particular to high-energy chirped pulse amplification lasers. The devices and the method of the invention allow a correction of the CEP of an ultrashort (femtosecond) pulsed laser. Moreover, the invention allows a shot-by-shot correction of the CEP at very high frequencies, going from a few Hz to several MHz. The device may advantageously be used at a frequency going from several tens of kHz to several MHz, to stabilize the CEP drift of a pulsed laser whose repetition rate is comprised in this same frequency range, which is not allowed by the devices based on the insertion of optical components (prismatic plates or other opto-mechanical modifications).
The devices and method of the invention may be used on a CPA laser of the prior art. | The present invention relates to a high-power femtosecond pulsed laser, the laser including: a source able to generate a train of input laser pulses having an envelope frequency and a carrier frequency; a chirped pulse amplification unit; and, a unit for controlling the phase drift between the envelope frequency and the carrier frequency of the output laser pulses. According to the invention, the unit for controlling the phase drift between the envelope frequency and the carrier frequency includes electro-optical phase-modulation unit that are placed on an optical path of the chirped pulse amplification unit in order to stabilize the phase drift between the envelope frequency and the carrier frequency of the output laser pulses as a function of time. | 7 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention is related to a furnishing light, particularly a design used for enhancing a visual sensation of an environment through object installation and display.
DESCRIPTION OF THE PRIOR ART
[0002] Usually an indoor furnishing light is of a simple design in structure and thus monotonous without variety. Recently living standard of people has increased and therefore demand on decorating lights, which can enrich a living atmosphere or enhance visual sensation, has increased as well. A function of furnishing light is for not only illumination but also atmosphere enrichment and visual effect in order to attract consumers, increase their will of purchasing and strengthen product competitiveness.
[0003] Although the furnishing light of the prior art can achieve illumination effect, that alone without variety in decorating function is unlikely to have consumers' purchase.
SUMMARY OF THE INVENTION
[0004] An objective of the present invention is to enrich the visual effect of a furnishing light in order to strengthen its competitiveness.
[0005] Therefore the present invention is to provide a furnishing light that mainly includes:
[0006] a base, which has an upward opening, inside the base provided with a control circuit and at least an illuminator connected therewith;
[0007] a projecting element, which is in a cylinder shape encircling the illuminator and provided with a transparent area and an opaque area;
[0008] a lens, which is positioned at a top of the projecting element; and
[0009] a casing, which is in a hollow and transparent three-dimension form with a downward opening, is securely connected to a top of the base so as to encapsulate both the projecting element and the lens and provided with a projecting area, which is corresponding with the lens.
[0010] Thereby when the base is turned on with electricity supplied, a light produced by the illuminator will transmits through the transparent area of the projecting element so as to project a contour of the transparent area onto the casing. Further, a portion of the light transmits and refracts through the lens so as to project the contour of the projecting area out of the casing for enhancing the decorating effect of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic diagram illustrating a disassembly of a preferred embodiment of the present invention.
[0012] FIG. 2 is a schematic diagram illustrating an assembly of the preferred embodiment of the present invention.
[0013] FIG. 3 is a schematic diagram illustrating a cross-section of the preferred embodiment of the present invention.
[0014] FIG. 3 a is a schematic diagram illustrating a local enlarged view of FIG. 3 .
[0015] FIG. 4 is a schematic diagram illustrating a dim-light assembly as the other preferred embodiment of the present invention.
[0016] FIG. 5 is a schematic diagram illustrating a cross-section of the dim-light assembly of the other preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Please refer FIGS. 1 to 3 a illustrating a preferred embodiment of a furnishing light ( 1 ) of the present invention, which is a suitable structure for decoration or dim-light, including a base ( 2 ), a projecting element ( 3 ), a lens ( 4 ) and a casing ( 5 ) that the projecting element ( 3 ) is positioned at the base ( 2 ), the lens ( 4 ) is positioned at a top of the projecting element ( 3 ) and the casing ( 5 ) is securely connected to a top of the base ( 2 ) so as to encapsulate both the projecting element ( 3 ) and the lens ( 4 ).
[0018] The base ( 2 ) is provided with an upward opening ( 21 ), underneath which a flange ( 22 ) is provided, that a control circuit ( 23 ) and multiply illuminators ( 24 ), which are electrically connected therewith, are provided inside the base ( 2 ). In this embodiment the illuminators ( 24 ) are LED bulbs that are controlled by the control circuit ( 23 ) for their flashing frequency and change in colors. Further an outer circumference of the base ( 2 ) is provided with a switch ( 25 ), which is electrically connected with the control circuit ( 23 ). An electricity source to the base ( 2 ) can be one of a battery, an alternate current supply or a direct current supply that the electricity source is of broad variety and therefore omitted as its exclusion in the scope of claim of the present invention.
[0019] The projecting element ( 3 ) is in a cylinder shape, which encircles the illuminators ( 24 ), to be embedded to an outer periphery of the flange ( 22 ) of the base ( 2 ) and then applied with adhesive so as to securely position the projecting element ( 3 ) to the base ( 2 ). The projecting element ( 3 ) is provided with a transparent area ( 31 ) and an opaque area ( 32 ) as made of flexible and transparent plastic film. The opaque area ( 32 ) is by a treatment of painting, tap application or other means in order to shade the transmission of light and thus leave the area without treatment in a transparent state. The transparent area ( 31 ) can be in a form of figure, character, geometry texture, and so on that multiply star figures are used for illustration purpose in this embodiment.
[0020] The lens ( 4 ) is in a shape of cap, securely positioned at a top of the projecting element ( 3 ) and configured with a slope area ( 41 ), which consists of multiply slopes, at a surface toward the base ( 2 ) while a convex area ( 42 ) is configured at a surface of the lens ( 4 ) opposite to the base ( 2 ). A skirt edge ( 43 ) is extended at a circumference of the lens ( 4 ) in order to match a circumference of the projecting element ( 3 ) so as to constrain a radial movement of the lens ( 4 ) at the top of the projecting element ( 3 ).
[0021] The casing ( 5 ) is securely connected to the top of the base ( 2 ), in a form of hollow and transparent sphere and provided with a downward opening ( 51 ) from which a pipe section ( 52 ) is extended downward. In this embodiment the pipe section ( 52 ) of the casing ( 5 ) is used to insert into the opening ( 21 ) of the base ( 2 ) such that the casing ( 5 ) encircles both the projecting element ( 3 ) and the lens ( 4 ). The casing ( 5 ) is provided with a projecting area ( 53 ), which is corresponding to the lens ( 4 ), in a transparent state that an area of the casing ( 5 ) other than the projecting area ( 53 ) is provided with a texture ( 54 ), which can be by matte treatment or treatment with texture. In this preferred embodiment matte treatment is used for illustration purpose.
[0022] According to the above-mentioned, when the base ( 2 ) is turned on with electricity supplied, the illuminators ( 24 ) produce an upward light that is distributed inside the projecting element ( 3 ) and then transmits through the transparent area ( 31 ) outward so as to project a contour thereof onto the casing ( 5 ). Further, a portion of the light transmits into the slope area ( 41 ) of the lens ( 4 ) and then refracts through the convex area ( 42 ) that the contour of the transparent area ( 31 ) is thus projected at the slope area ( 41 ) of the lens ( 4 ) for enhancing the decorating effect of the present invention.
[0023] Please refer FIGS. 4 and 5 illustrating the other embodiment of a dim-light of the present invention. A portion of the outer circumference of the base ( 2 ) is formed as a flat surface ( 26 ) within which a hole ( 27 ) is provided for physically connecting an internal space of the base ( 2 ) that a dim-light plug ( 6 ) is installed at the hole ( 27 ) and electrically connected with the control circuit ( 23 ).
[0024] Thereby the dim-light embodiment of the present invention is to use the plug ( 6 ) installed at the base ( 2 ) for plugging into a socket on a wall (A) for conducting electricity. The transmission of light is the same as the above-mentioned embodiment with a deviation because the dim-light is usually placed near the wall (A) that the contour of the transparent area ( 31 ) of the projecting element ( 3 ) is projected on the casing ( 5 ) and then to the wall (A) while the projection on the slope area ( 41 ) of the lens ( 4 ) is projected to the wall (A) at the same time. Therefore a visual sensation of light and shadow is produced at the wall (A) near the dim-light.
[0025] Further a motor, which is electrically connected with the control circuit ( 23 ), and a turn-table driven thereby can be installed inside the base ( 2 ) that the projecting element ( 3 ) is positioned to the turn-table. When the present invention is turned on with electricity supplied, the turn-table will rotate together with the projecting element ( 3 ) that the light passing through the transparent area ( 31 ) of the projecting element ( 3 ) will have a dynamic effect. Because the mentioned motor and turn-table are structures of prior art, they are omitted from the figures. | A furnishing light mainly includes a base, inside which provided with an illuminator, a projecting element with a transparent area encircling the illuminator, a lens positioned above the projecting element and a casing with a projecting area for encapsulating both the projecting element and lens. Thereby a light from the illuminator projects a contour of the transparent area to the casing meanwhile refracts through the lens to distribute over the projecting area. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the field of data communications.
2. Related Art
With the advent of the personal computer and the tremendous popularity of the Internet and on-line services, the number of computers connected to the public switched telephone network (PSTN) has grown immensely over the past decade. It is estimated that 20-30% of all calls placed on the telephone network are established for the purpose of allowing one terminal or computer device to communicate with another computer device. These calls are known as data calls. The characteristics of a data call are unlike the characteristics of voice calls. A voice call normally lasts for 3 centennial call seconds (CCS), which is about five minutes, whereas a data call normally lasts for 36 CCS (about an hour). This presents a problem because the telephone network was not designed for handling the relatively long duration data calls. Consequently, as result of the tremendous increase in the number of data calls served by the phone network, the network is increasingly being overloaded.
FIG. 1 illustrates a representative overloaded PSTN 102 . PSTN 102 comprises a plurality of central office switches (CO) 110 , 112 , 114 , 116 and at least one STP/SCP node 118 . Each CO has a serving area, which is the geographical area in which the CO is located: all subscribers in that area are served by that CO.
FIG. 1 shows a user 103 that desires to connect data terminal device 104 with remote data terminal device 124 using PSTN 102 . Data terminal device 104 is connected to PSTN CO 110 through data communication device 106 , such as a modem, and dial media 108 .
In order to establish a connection between data terminal device 104 and remote data terminal device 124 , data terminal device 104 directs data communication device 106 to place a call to remote access server (RAS) 120 using PSTN 102 . Data communication device 106 places a call to RAS 120 by sending a call request to PSTN CO 110 . Upon receiving the call request from data communication device 106 , the PSTN establishes a circuit from the originating CO 110 to RAS 120 through terminating CO 114 . RAS 120 is connected to data network 122 , which is connected to remote data terminal device 124 .
RAS 120 provides full data call establishment by performing the reverse of the processes performed by data communication device 106 . The processes performed by data communication device 106 includes the processes of: (1) data compression; (2) error correction; (3) link layer framing; and (4) modulation, in that order. Thus, RAS 120 provides full data call establishment by performing the following steps in the following order: (1) demodulation; (2) link layer framing; (3) error correction; and (4) data decompression.
Modulation refers to the conversion of a binary bit stream into a modulated signal within the voice frequency range. The facilities of a PSTN are designed to handle voice traffic, not binary data. Thus, to transmit binary data through the phone network it is necessary to perform the process of modulation. The modulated signal is then used to “carry” the binary data through the phone network. Demodulation refers to the process of converting a modulated signal back into the original binary data. Consequently, a modulator/demodulator (i.e., modem) is necessary to transmit binary data from one computer to a second computer through the phone network.
The process of link layer framing refers to a process of encapsulating data within a frame for transmission on the physical layer. Encapsulating data within a frame enables the error correction processing.
After the call is established by RAS 120 , data communication device 106 accepts user data from data terminal device 104 for transmission to RAS 120 . Data communication device 106 prepares the user data for transmission over the PSTN by first encapsulating the data in a protocol (such as PPP), compressing the encapsulated data, applying error control, framing the data in a link layer frame, and modulating the link layer frame. RAS 120 receives the modulated signal, demodulates the signal to recover the link layer frame, removes the link layer framing, checks for errors, decompresses the data, and de-encapsulates the call to recover the user data in its original form. The user data is then forwarded to remote data terminal device 124 through data network 122 .
The circuit set up between CO 110 and CO 114 remains in use until data communication device 106 terminates the call and releases the circuit, regardless of whether actual data is being transmitted. Thus, valuable PSTN circuits are consumed from data communication device 106 to local CO 110 , between originating CO 110 to terminating CO 114 , and from terminating CO 114 to the RAS.
To conserve valuable PSTN circuits, what is needed is a system to bypass the PSTN by capturing data calls at the originating CO and transmitting the compressed user data associated with the data call through a data network to a device that will then decompress the data and transmit the decompressed data to the intended destination.
SUMMARY OF THE INVENTION
In a system wherein a data communication device receives user data from a data terminal device, compresses the user data, encapsulates the compressed user data within a link layer frame, and transmits a modulated signal corresponding to the link layer frame to a switch within a telephone circuit switch network, the present invention provides a system for transporting the compressed form of the user data through a data network, thereby bypassing the telephone network.
The present invention includes a remote access concentrator (RAC) connected to a network access controller (NAC) through the data network. The RAC is connected to the switch within the telephone network and includes a network interface for receiving the modulated signal from the switch. The RAC also includes a demodulator to demodulate the modulated signal so as to recover the link layer frame. After recovering the link layer frame, the RAC tunnels the link layer frame through the data network to the NAC. Since the link layer frame contains the compressed form of the user data, the compressed user data is transported through the data network.
The NAC receives the tunneled link layer frame from the RAC and extracts the compressed user data from the link layer frame. The NAC then decompresses the compressed user data to recover the user data in its original form. The user data is then processed by the NAC according to the user data type. Finally, the NAC forwards the user data to the remote data terminal device.
The invention supports a variety of user data types, including: Asynchronous data, Point to Point Protocol (PPP), and Serial Line Internet Protocol (SLIP). The invention's ability to support a variety of data types is based on the RAC tunneling the link layer frame to the NAC, such that the RAC does not directly process the user data.
In a first embodiment of the present invention, the switch within the telephone network is a CO. In a second embodiment of the present invention, the switch is a Competitive Local Exchange Carrier (CLEC) switch.
Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention.
FIG. 1 illustrates a representative public switched telephone network.
FIG. 2 illustrates a network configuration according to a first embodiment of the present invention.
FIG. 3 illustrates a procedure, according to the present invention, for providing call establishment.
FIG. 4 illustrates the flow of data from data terminal 104 to remote data terminal 124 , according to the present invention.
FIG. 5 illustrates a second embodiment of the present invention.
FIG. 6 is a diagram further illustrating a remote access concentrator.
FIG. 7 is a diagram further illustrating a network access controller.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The system of the present invention captures data calls at an entrance of the public switched telephone network (PSTN) (e.g., the originating CO) and transports the compressed form of the user data associated with the data call through a data network, thereby bypassing the PSTN. The advantage of this invention is that the consumption of PSTN interconnect circuitry is reduced and that the user data is transported in its compressed form though a data network.
FIG. 2 illustrates an overview of an embodiment of the present invention. The present invention includes a remote access concentrator (RAC) 210 , a data network 220 , and a network access controller (NAC) 230 .
RAC 210 is connected to data terminal device 104 though originating CO 110 and to NAC 230 through data network 220 . RAC 210 is locally connected to CO 110 . Although it is not shown, each CO 112 , 114 , 116 can have a locally connected RAC to service users in each COs respective geographic areas. NAC 230 is connected to remote data terminal device 124 through data network 122 . Because RAC 210 is locally connected to CO 110 , the only PSTN circuits that will be consumed are the circuits from data communication device 106 to originating CO 110 , and the circuits between originating CO 110 and RAC 210 .
Data terminal device 104 includes but is not limited to such devices as personal computers, laptop computers, and workstations. Similarly, data communication device 106 includes but is not limited to such devices as analog or digital modems, ISDN terminal adapters, or wireless modems. It should also be noted that data terminal device 104 and data communication device 106 can form one integral unit or can exist as two separate units.
The invention essentially splits the functionality of the typical RAS 120 into two new parts: RAC 210 and NAC 230 . RAC 210 performs the link layer and modulation/demodulation functions of RAS 120 , while NAC 230 performs the link layer functions and all functions existing above the link layer, such as error correction and data compression/decompression.
The link layer is the optimum area in which to split the RAS 120 functionality because the users data is compressed at that layer and the link layer consists of uniform frames. Because RAC 210 does not perform any functions above the link layer (e.g., RAC 210 does not perform data decompression) RAC 210 is able to transmit the compressed user data to NAC 230 for further processing. Consequently, the system of the present invention utilizes fewer data network resources than a system where the user data is transported in its uncompressed form. Substantial cost savings and efficiency gains are thereby realized. Additionally, RAC 210 is completely protocol independent because it does not process above the link layer.
FIG. 3 illustrates a procedure, according to the present invention, for providing call establishment when data terminal device 104 initiates a data call to remote data terminal 124 .
The procedure begins at step 302 where control immediately passes to step 304 . In step 304 data terminal device 104 directs data communication device (DCD) 106 to place a call to RAC 210 using PSTN 102 . In step 306 a call request is received at CO 110 and in step 308 CO 110 will set up a local circuit connecting DCD 106 to RAC 210 . After step 308 control passes to steps 310 and 312 in parallel. In step 310 , RAC 210 receives the call and uniquely provides partial data call establishment by demodulating the modulated signal transmitted by DCD 106 and by performing link layer framing. In step 312 , RAC 210 contacts the associated NAC 230 over data network 220 to request a virtual port for the continuation of matching and completing the remainder of call establishment. Instep 314 NAC 230 signals RAC 210 instructing RAC 210 which virtual port will continue and complete the call establishment. After step 314 , RAC 210 and NAC 230 are connected via data network 220 . In step 316 , RAC 210 forwards the link layer frames transmitted by DCD 106 to NAC 230 so that NAC 230 can complete call establishment. RAC 210 forwards the link layer frames through data network 220 . In step 318 , NAC 230 completes call establishment on its virtual port by processing the link layer frames received from RAC 210 .
After the call is established by RAC 210 and NAC 230 , DCD 106 will begin accepting user data from terminal device 104 for transmission to RAC 210 , and ultimately for transmission to remote data terminal 124 .
FIG. 4 illustrates the flow of data from data terminal 104 to remote data terminal 124 , according to the present invention. FIG. 4 also illustrates how the functionality previously performed by RAS 120 is now performed by RAC 210 and NAC 230 .
Data terminal device 104 generates user data 402 , which is sent to DCD 106 for transmission to remote data terminal 124 . The present invention supports a variety of user data 402 types, including: Asynchronous data, Point to Point Protocol (PPP), and Serial Line Internet Protocol (SLIP).
Upon receiving user data 402 , DCD 106 performs data compression 408 . A compression algorithm commonly implemented in data communication devices is the V.42bis compression standard. However, other compression algorithms are contemplated by the present invention.
After compressing the data, DCD 106 typically adds error correction information 414 to the compressed data 412 . As an example, DCD 106 employs the V.42 error correction standard. The compressed data and the error correction information 414 are then encapsulated within a link layer frame 418 . Link layer frame 418 is modulated 420 to produce modulated signal 422 for transmission on to dial media 108 . Dial media 108 can include, for example, plain old telephone service (POTS), integrated services digital network (ISDN) services, and analog and digital wireless services. A variety of modulation schemes 420 can be used by DCD 106 . An example modulation scheme is the V.34 standard. Other modulation schemes are contemplated by the present invention, such as ISDN modulation schemes.
Modulated signal 422 passes through CO 110 and is received at RAC 210 . RAC 210 performs demodulation 424 and link layer processing 428 so as to recover link layer frame 418 . After recovering link layer frame 418 , RAC 210 will tunnel link layer frame 418 through data network 220 to NAC 230 . RAC 210 tunnels link layer frame 418 through data network 220 by encapsulating it in a data network protocol. A variety of protocols may be used to tunnel link layer frame 418 . Such protocols include but are not limited to TCP, ATM, and Frame Relay.
NAC 230 will receive the data network protocol encapsulated link layer frame and remove the protocol encapsulation to recover link layer frame 418 . NAC 230 will then extract the compressed user data and error correction information 414 from link layer frame 418 . Next, NAC 230 will use the error correction information 414 to fix errors that may have occurred during transmission. Following that step, NAC 230 will decompress the compressed user data. Next, NAC 230 will perform protocol processing corresponding to the type of user data 402 transmitted by data terminal device 104 . For example, if user data 402 is of the PPP protocol type, NAC 230 will perform PPP processing. Finally, NAC 230 forwards user data 402 to remote data terminal 124 via data network 122 .
As is evident from data flow diagram 400 , the compressed form of user data 402 is transported through data network 220 . By transporting the compressed form of user data 402 through data network 220 , as opposed to the un-compressed form, cost savings and efficiency gains are realized because a smaller amount of data traverses data network 220 . For example, the V.42bis compression algorithm yields approximately a 4:1 compression ratio.
FIG. 5 illustrates another environment in which the present invention is useful. In this environment, RAC 210 is connected to a competitive local exchange carrier (CLEC) switch 510 instead of a CO. CLEC 510 is connected to a plurality of local access and transport areas (LATA). The present invention functions exactly the same in the environment illustrated in FIG. 5 as it does in the environment shown in FIG. 2 . Thus, the process of FIG. 3 and the data flow diagram of FIG. 4 require no modification to operate in the environment shown in FIG. 5 .
FIG. 6 is a diagram illustrating a more detailed view of RAC 210 . RAC 210 includes: network interface 610 for connecting to a PSTN switch, such as a CO 110 or CLEC 510 ; network interface 612 for connecting to a data network; processor 620 ; control logic 622 for enabling processor 620 to demodulate the signal received from DCD 106 ; memory 630 for storing link layer frames 418 ; and encapsulator 640 for removing frames from memory and encapsulating the frames within a data network protocol so that the frame can be tunneled through a data network to a virtual port of NAC 230 . In the preferred embodiment, processor 620 is a digital signal processor. The implementation of control logic 622 is well known in the art.
FIG. 7 is a diagram illustrating a more detailed view of NAC 230 . NAC 230 includes: network interface 710 for connecting to data network 220 ; network interface 712 for connecting to Internet type network 122 ; processor 720 ; control logic 722 for enabling processor 720 to process the tunneled link layer frames received from RAC 210 and to decompress user data; memory 730 for storing user data; and routing mechanism 740 for forwarding user data to data terminal device 124 connected to data network 122 .
While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example, and not limitation. It will be understood by those skilled in the relevant art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the following claims. Thus the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. | A data bypass system for removing data traffic from a public switched telecommunications network designed for carrying voice traffic includes a remote access concentrator for receiving a modulated signal corresponding to the data traffic, demodulating the signal to recover the link layer frames that comprise the data traffic, and tunneling the link layer frames through a data network to a network access controller for extracting compressed data contained within the link layer frames, decompressing the compressed data, performing error correction, performing protocol processing, and transmitting the decompressed data to a data terminal device. | 7 |
This is a division of application Ser. No. 08/521,005 filed Aug. 30, 1995 now allowed as U.S. Pat. No. 5,604,267, issued Feb. 18, 1997.
TECHNICAL FIELD
The present invention pertains to polyurethane froth foam. More particularly, the present invention pertains to a process for preparing polyurethane froth foam with enhanced processability.
BACKGROUND ART
Especially since the advent of the Montreal Protocol severely limiting the use of CFC (chlorfluorocarbon) and other halogenated hydrocarbon blowing agents, frothed foams have become increasingly important. By the term "frothed foam" and similar terms is meant a cellular foam product the cells of which are formed by the mechanical incorporation of inert gas, particularly air, nitrogen, carbon dioxide, or argon, into a curing polymer system, with or without the aid of small amounts of blowing agents of the physical or chemical types. Froth foams have been prepared from polymer systems such as SBR latex, PVC plastisol, and polyurethane, to the latter of which the present invention pertains.
Polyurethane froth foams have been used for numerous years, for example in the preparation of foam-backed industrial carpet and carpet underlay. See, e.g., "Mechanically Frothed Urethane: A New Process for Controlled Gauge, High Density Foam", L. Marlin et al., J. CELL PLAS., v. 11, No. 6, November/December 1975, and U.S. Pat. Nos. 4,216,177; 4,336,089; 4,483,894; 3,706,681; 3,755,212; 3,772,224; 3,821,130; and 3,862,879, which are herein incorporated by reference.
In the processes disclosed in these references, the polyurethane reactive components: the isocyanate ingredients (A-side), and polyol ingredients (B-side) are each stored in separate, often heated, and sometimes aerated holding tanks. The two components are then metered into a standard froth foam mixing head at low pressure, to which is also fed a supply of compressed air. The mix head contains mixing blades or similar devices moving at high speed, which whips air into the reacting mixture to produce a foam having a consistency not unlike shaving cream or whipped cream.
Due to the intensive mixing which occurs in the froth foam head, as well as the air normally introduced either intentionally or unintentionally into the B-side holding tank, premixing of the reactive foam ingredients has not been considered necessary. Mixers such as those from Hobart or Oakes, of rather conventional construction, have been thought sufficient to provide thorough mixing of foam-forming ingredients. Even more thorough and efficient mixers include stator cylinders containing multiple rows of pins within which revolves a rotor also carrying multiple rows of pins which can rotate between the stator pins. Such mixers are available, for example, from Lessco Corp., Dalton, Ga.
The froth foam is allowed to exit the mixer onto a conveyor belt on which, for example, a release sheet or carpet backing travels, is leveled with the aid of a roller or doctor blade, and generally passed through a curing oven or heated with radiant energy to cure the foam. For some uses, the foam is conveyed through a large diameter hose to the point of application. For many applications, for example carpet underlay, considerable amounts of fillers such as calcium carbonate or alumina trihydrate are added to the B-side to increase the density and load bearing capacity of the foam.
Despite representing standard industry practice for many years, the processes previously described suffer from numerous drawbacks. For example, the change in ambient temperature which may occur between day-shifts and night-shifts or even between the morning and afternoon of the same shift can cause differences in the rate of the urethane polymerization reaction. Changes in atmospheric moisture can also affect the process as can changes in conveyor belt temperatures, etc., caused by continuous running of the process. In the past, changing processing chemistry past merely adjusting A-side/B-side ratios has required halting the process, adjusting the A-side and/or B-side ingredients in the holding tanks, and restarting the process. However, in most cases, the frothing head, and foam conveyor hoses when used, must be cleaned out. The result is loss of manufacturing time which increases cost of the product. In U.S. Pat. No. 4,925,508, for example, is proposed a disposable polyethylene or polystyrene pre-expansion chamber designed to partially reduce down-time.
In the manufacture of filled froth foam, further problems arise. In commercial processes, fillers such as calcium carbonate or alumina trihydrate are added to the B-side (polyol) in quantities up to 300 parts per 100 parts polyol. The filler and polyol components are intensively high-shear mixed, and transferred to a holding tank which is either unstirred or stirred with but modest agitation. Air may be incorporated into the filler/polyol to aid in the froth foaming process in addition to air supplied at the froth foam head, or may be "unintentionally incorporated" due to air entrained in the filler or incorporated from the head space above the polyol during high speed mixing. Once in the holding tank, however, entrained air tends to rise to the top while filler tends to settle to the bottom. There may be more than a two-fold difference between the B-side density at the bottom of the tank and the top of the tank, i.e., 6 lbs/gal at the top and 14 lbs/gal at the bottom. Since the pumps supplying the froth foam head are positive displacement pumps, not only does the density of the product change over time, but the polymerization chemistry changes as well due to the variation in polyol content of the B-side caused by movement of air and filler.
To counteract the difference in density, some processes link the low pressure positive displacement pumps with mass flow devices which measure mass flow rather than volume flow and adjust volume flow accordingly in a closed loop process. While such measures maintain density, they do not maintain chemical stoichiometry, but rather can adversely affect stoichiometry, since the less dense B-side, the volume of which the closed loop process will cause to increase, may already contain a higher weight percent polyol than that desired.
Also important in filled systems is the phenomenon of B-side viscosity increase over time. Over time, the filler/polyol mixture increases considerably in viscosity, perhaps due to greater wetting of the filler surfaces with polyol. It is not uncommon for the viscosity to increase from 2000 cps to 4000 cps over a time of two hours, for example. The increased viscosity reduces pumping efficiency, and more importantly, adversely affects the frothing operation. The result of this and the foregoing factors make continuous production problematic. It is not uncommon for production to be halted every few hours to adjust process parameters, with the deleterious effects on process time previously described.
At times, it is desirous to provide a froth foam product which is multilayered, for example a first layer of lower density and higher resiliency and a second layer of higher density and lesser resiliency. In the past, production of such products has met with but limited success. At the exterior of the first produced foam surface, the froth exhibits coalescence, forming relatively large cells. Since the second froth foam layer, like the first, does not exhibit the expansion typical of blown polyurethane foams which might be sufficient to force the expanding polyurethane into the surface of the first layer, a second froth foam layer does not adhere well to the first layer, resulting in the potential for delamination during production and/or use.
It would be desirable to provide a process for the production of polyurethane froth foam in which the polyurethane stoichiometry can be adjusted on the fly, rather than requiring shut down. It would be further desirable to provide a process for the preparation of filled polyurethane froth foam in a consistent and reliable manner without resorting to use of mass flow meters and other devices. It would be yet further desirable to provide a process for producing polyurethane froth foam wherein multiple layers of foam may be successfully applied. It is further desirable to provide a process where uniform froth foam can be produced, even at low density.
SUMMARY OF THE INVENTION
It has now been surprisingly discovered that consistent, high quality polyurethane froth foam may be produced in a process where the polyurethane reactive ingredients are first delivered to a standard high pressure mix head prior to entry into a standard froth foam head. In a preferred embodiment, filled froth foams are produced by blending filler in-line with the polyol stream prior to entry into the high pressure mix head. The froth foam produced exhibits more uniform cell structure than prior art froth foams, and unexpectedly generates a smooth interface with minimum coalescence, allowing for production of high quality multiple layer froth foam products.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a schematic of one embodiment of the process of the subject invention;
FIG. 2 is a scanning electron photomicrograph of a froth foam of the subject invention;
FIG. 3 is a scanning electron photomicrograph of a two layered froth foam of the subject invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The process of the subject invention may be described with reference to the process schematic of FIG. 1. In FIG. 1, the polyol B-side is contained in holding tank 101. The B-side may be all polyol, or polyol with chain extenders, cross-linkers, catalysts, and other additives and auxiliaries known to the field of polyurethanes. The polyol is pumped from holding tank 101 through optional in-line blender 103 by suitable means, for example variable speed metering pump 105. High pressure pump 107 injects the B-side into high pressure mix head 109, which advantageously may be of the impingement mixing type.
At 111 is the A-side isocyanate tank, from which isocaynate is directed to the high pressure mix head 109 by high pressure pump 113. Compressed air is directed to the high pressure mix head through line 115, the amount of air determined by the air flow meter 117, and the volume controlled by valve 119 or by adjusting the pressure of supply air. From the high pressure mix head 109, the reactive mixture flows to froth foam mixing head 121 which may also include an inlet 122 for additional frothing gas, from which it is dispersed onto a conveyor or through a hose to the point of application.
The optional blender 103 consists of a standard liquid/solid blender having a supply hopper 123 containing filler, which is metered into the blender by means of auger 125. Standard techniques are used to measure and adjust filler weight added to the polyol.
Also shown in FIG. 1, entering high pressure mix head 109 are inlets 127 and 129 which may be used to supply additional streams of polyurethane ingredients such as catalyst solutions, cross-linkers, surfactants, colorants, additional isocyanate or polyol, auxiliary blowing agents, e.g. water, low boiling hydrocarbons, CFC-22, and the like. Preferably, the process is performed without auxiliary blowing agents. Additional inlets to the mix head may be provided as well, the various inlets providing for maximum flexibility in polyurethane stoichiometry.
The various components are standard components and readily available. Variable speed low and high pressure pumps are standard, off-the-shelf items available from numerous suppliers. A suitable filler/polyol blending unit is a Turburlizer I filler blender, available from Darwin Enterprises, Inc., Dalton, Ga. Other blenders are suitable as well. Likewise, high pressure mix heads are available from sources such as Cincinnati Milicron, Elastogran GmbH, Hennecke, and other suppliers. A suitable high pressure mix head is a carpet backing foam machine head available from Hennecke Equipment Co., Pittsburgh, Pa. Suitable froth foam heads include those available from Hobart, Oakes, and Lessco. A preferred froth, foam head is a "Firestone" type head designated Lessco System Superfoam Blender available from Lessco Corp., Dalton, Ga.
Suitable formulations for preparing froth foam are disclosed in the numerous references cited earlier, and are well known to those skilled in the art. A preferred froth foam formulation is ARCOL® froth foam mix available from ARCO Chemical Co., Newtown Square, Pa., which employs, in addition to polyol, silicone surfactant L5614 and urethane-promoting catalyst LC-5615, both available from OSi, Inc., and isocyanate E-448 available from Bayer, Pittsburgh, Pa.
The polyurethane froth foam formulation itself forms no part of the present invention, and many formulations are suitable. The filler may be any filler generally used, e.g. calcium carbonate, alumina trihydrate, talc, various clay minerals, e.g. bentonite, or mixtures of these.
FIG. 2 is a scanning electron photomicrograph of a section taken through a foam of the present invention. Noteworthy is the uniformity of the cell structure and the presence of large numbers of complete cells despite the shear required to provide an edge suitable for examination. FIG. 3 is a similar photomicrograph of a two layer froth foam product. Noteworthy is the fine and uniform interface between the two layers, the first layer showing virtually no coalescence. The two layer foam was produced by curing the first layer prior to application of the second layer (wet on dry).
The advantages of the subject process are numerous. In addition to providing a high quality product, even in the lower density ranges, two layer or multiple layer quality foams may be produced. Moreover, the stoichiometry of the product may be readily adjusted, either manually or under computer control, by adjusting the volume of the various feed streams to the high pressure mix head. The process is particularly flexible when rather than merely A- and B-side streams, individual components are supplied to the mix head.
Of particular note, however, is the uniformity produced in filled froth foams when filler is added to polyol in the in-line blender. Since the filler/polyol blend is injected into the high pressure mix head after only a short time, the viscosity of the blend remains low and exhibits little or no variation in viscosity. Moreover, due to the absence of increased viscosity over time, larger amounts of filler can be used, which otherwise, in a conventional process, would render the B-side too viscous or even gelled or thixotropic. Suitable amounts of filler range up to 450 parts per 100 parts by weight polyol, preferably 50 parts to 450 parts filler per 100 parts polyol.
Most especially advantageous in filled foams is the lack of density variation of the B-side/filler blend seen when conventional holding tanks are used. The stoichiometry and density both remain essentially constant over extended periods of time, and the process can be conducted without the complication and added expense of mass flow meters and associated equipment.
Having now fully described the invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention as set forth herein. | High quality, consistent polyurethane froth foams, both filled and unfilled, are prepared by directing polyol, isocyanate, and optionally other polyurethane-forming ingredients to a high pressure mix head prior to introducing the mixture to a froth foaming head. Changes in stoichiometry may be made rapidly without shut-down. An in-line blender incorporated filler into the polyol stream minimizing density differentials normally encountered in the holding tank, maintaining low and reproducible viscosity, and allowing for greater amounts of filler than otherwise possible. | 8 |
BACKGROUND OF THE INVENTION
The field of the present invention relates to the prevention and treatment of Acquired Immune Deficiency Syndrome (AIDS), systemic lupus erythematosus (SLE) and related diseases. As used herein, the various titles, and other such headings are intended for guidance, and should not be construed as limiting on the present invention.
Over the last fifteen years a major international research effort has been directed at developing effective vaccines and therapies for AIDS but has so far only achieved very limited success. AIDS is a disease which results from chronic infection by Human Immunodeficiency Virus (HIV). At least ten million people worldwide and at least one million people in the USA are infected with HIV. It is widely accepted that AIDS is caused by HIV but the precisely how HIV infection leads to AIDS is still a matter of active scientific investigation. Current research into developing a vaccine to prevent AIDS is based on attempting to increase immune responses to the HIV but has so far failed to produce an effective product. There are now many thousands publications which describe attempts to develop AIDS therapies and vaccines by stimulating the human immune system to recognise and destroy the virus. The main problem appears to be that antibodies and cytotoxic T cell responses stimulated by prototype vaccines fail to protect against either HIV infection or AIDS disease progression because of the rapid mutation rate of HIV.
A number of drugs have been developed for the treatment of AIDS (mainly anti-viral drugs with a similar mode of action to 3'-azido-3'-deoxythymidine, AZT), but none have been demonstrated to prevent the development of AIDS after HIV infection. The main problem is that HIV mutates rapidly leading to changes in the virally encoded proteins which are the target for antiviral drugs and drug resistance develops quickly.
Systemic lupus erythematosus (SLE) is a disease which is normally viewed as being completely unrelated to AIDS. SLE is an autoimmune disease and effects mainly women. Over half a million women in the USA suffer from mild to severe SLE. SLE is an autoimmune disease with many immunological abnormalities such as lymphadenopathy, hypergaminagloblulimemia, leukopenia, deposition of antigen-antibody complexes and autoantibodies resulting in chronic generalized connective tissue disorders ranging from mild to severe marked by skin eruptions, arthralgiia, arthritis, anemia, visceral lesions, neurologic manifestations, fever and other constitution symptoms. Symptoms fluctuate in intensity over many years and SLE is normally controlled with immunosuppressive drugs ranging from non-steroidal anti-inflammatory drugs to immunosuppressive steroids but there is no effective treatment. SLE may be the result of immune activation triggered by a retrovirus but no retrovirus has been identified which has been show to cause SLE. GB 9411534.2 filed by Holms R. D, on 8th Jun. 1994 discloses how HIV induces an autoimmune mechanism related to SLE which eventually leads to AIDS.
SUMMARY OF THE INVENTION
The present invention is based on selectively decreasing certain immune responses to HIV using peptides based on human proteins particularly a human protein called ezrin, providing a novel and non-obvious solution to the problem of the prevention and treatment of AIDS. A number of investigators have described autoimmunity related to HIV infection but have not established that HIV induced autoimmunity directly causes AIDS. The present invention is based on my discovery of the molecular mechanism of HIV induced autoimmunity which leads to AIDS and parallels between HIV induced disease and autoimmune disease such as systemic lupus erythematosus (SLE). The present invention provides for preparations which inhibit autoimmune processes which lead to AIDS and SLE by the induction certain types of immunosuppression or immune tolerance. GB 9411534.2 filed by Holms R. D, on 8th Jun. 1994 discloses therapies and vaccines for the treatment and prevention of AIDS based on this novel autoimmune mechanism induced by HIV.
I propose that just before the HIV epidemic commenced, HIV acquired a small piece of human DNA which allowed it to evolve a specific mechanism to replicate more efficiently by activating the human immune system . Unfortunately, HIV encoded derivatives of this human sequence not only activate the system but also induce autoimmunity and apoptosis. When a peptide derived from the virus, in a complex with certain types of MHC, is seen as sufficiently foreign to induce an immune response but has sufficient sequence homology with human peptides to trigger T cells which recognise both viral and human antigens, there is a serious risk of a chronic autoimmune response. This type of molecular mimicry has been postulated for the induction of a number of autoimmune diseases including multiple sclerosis. Mammalian immune systems also tend to be strongly activated by foreign antigenic peptides which are very similar but not the same as self antigens.
The HIV amino acid sequence;
NH 2 ThrLysAlaLysArgArgValValGluArgGluLysArgCOOH(SEQ ID NO. 1),
at position 498 to 510 (in the conserved C4 region) at the carboxy-terminus of HIV gp120 (a predicted alpha-helical region) is encoded between the direct repeats of a putative transposable element and appears to be a recent addition of human DNA to the virus. It is an immunodominant region of gp 120 in man and accounts for up to 70% of the total antibody response generated to the virus in some individuals although the antibodies are not virus-neutralising. A peptide derived from this region is also a dominant MHC Class-I restricted epitope for the induction of Cytotoxic T Lymphocytes (CTL). The sequence is conserved in all isolates of HIV-1 and HIV-2 against a background of a high mutation frequency (it is even more stable than the CD4 binding site) but it is different from an equivalent SIV sequence.
This 13 amino acid sequence of HIV;
NH 2 ThrLysAlaLysArgArgValValGluArgGluLysArgCOOH(SEQ ID NO. 1), is likely to be an epitope
for the induction of autoimmunity as it has a high degree of homology (50% or greater) with certain human sequences. I have named amino acid sequences in HIV which mimic human sequences; Virus Homologous Peptide (referred to hereinafter as VHP) and the above HIV amino acid sequence VHP1. I have named the group of human amino acid sequences derived from endogenous human protein sequences which the virus mimics, Human Endogenous Peptide (referred to hereinafter as HEP).
Although I propose the following novel immunological process to describe the mechanism of action of these human peptides (HEPs), the following immunological process serves to illustrate the invention only, and should not be construed as limiting it in any way.
I suggest that there is a positive selection mechanism for mutants of HIV which maintain the HIV sequence VHP1 (NH 2 ThrLysAlaLysArgArgValValGluArgGluLysArgCOOH)(SEQ ID NO. 1) at position 498 to 510 (conserved C4 region) at the C-terminus of HIV gp120. This sequence is maintained because when it is presented by some MHC Class I molecules (particularly MHC Class I B8 and MHC Class I B35) and most MHC Class II DR molecules, it is important for inducing large numbers of activated T cells in which HIV infection and replication occurs. Unfortunately, the activated CD4+ T cells die or are killed rapidly after VHP1 activation and a population of VHP1 activated CD8+ T cells raise the level of autoreactive responses. Eventually the combination of both immunological processes leads to AIDS.
Chronic HIV infection results in continuous presentation of VHP1 produced by HIV and continuous stimulation of the immune system. Although the presence of activated of T cells is essential for HIV replication, HIV only infects and kills a small minority of the VHP1 activated T cells. The majority of the activated T cells die as a result of VHP1 over stimulation or are destroyed by negative feedback mechanisms in the immune system involving autoreactive T cells. T cells are continually produced by the body to make good these losses in a chronically infected HIV patient but the net result is a progressive decline in CD4+ T cells over a number of years.
I also propose that the continuous presentation of VHP peptide by certain MHC Class I molecules of HIV infected cells breaks the tolerance of the host immune system to self peptides such as those derived from ezrin and other HEPs presented on activated T and B cells. The general level of activation leads to the stimulation of autoreactive cytotoxic T cells and chronic B cell activation with the over production of a range of antibody molecules including autoreactive antibody. A key step in the activation of the autoimmune process in HIV infected individuals is the stimulation of autoreactive CD8+ cells which carry cross reactive T cell Receptor (TCR) molecules that recognise both VHP and HEP.
It is an object of this invention to prevent and treat AIDS and SLE and related disorders by the induction of specific immunological tolerance which inhibits the above pathological mechanism. It is an object of the invention to provide composition of matter comprising pharmaceutical grade purified peptide or a mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence with at least 50% homology over fourteen consecutive amino acids with the following human amino acid sequence:
NH 2 ThrGluLysLysArgArgGluThrValGluArgGluLysGluCOOH(SEQ ID NO. 2),
(the fourteen amino acid sequence hereinafter referred to as HEP1) and a purified peptide or mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence of at least five consecutive amino acids with 100% homology with HEP1. It is a purified object to provide a purified peptide comprising an amino acid sequence sufficiently duplicative of the fourteen amino acid sequence HEP1. It is a further object of the invention to provide a preparation of comprising peptides and peptide derivatives with at least 50% homology over fourteen consecutive amino acids with HEP1 and a purified peptide or mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence of at least five consecutive amino acids with 100% homology with HEP1, for the prevention and treatment of AIDS and related disorders which inhibits in vivo in man, partially or completely, HIV virus as measured by either an HIV p24 antigen assay in vitro or by an HIV infectivity assay in vitro. It is a further object of this invention to provide a preparation comprising peptides and peptide derivatives with at least 50% homology over fourteen consecutive amino acids with HEP1 and a purified peptide or mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence of at least five consecutive amino acids with 100% homology with HEP1, for the prevention and treatment of AIDS and related disorders, and for the prevention and treatment of Systemic Lupus Erythematosus and related disorders, which inhibits in vivo in man , partially or completely, autoimmune or autoreactive responses measured in vitro in a T cell Proliferation Assay.
The close similarity between foreign VHP1 and self HEP1 when presented by certain MHC molecules and the possible immunoregulatory role of HEP1 in the healthy immune system, leads to strong stimulatory signals being transmitted through the immune system during HIV infection. The administration of HEP1 above the threshold for immunological tolerance induction is likely to block the VHP1 mediated activation of the immune system by HIV infected T cells. The clinical result of HEP1 administration predicted from the above model of HIV induced autoimmunity is lower levels of immune activation, a rise in CD4 T cell levels and a fall in the level of chronic HIV infection. (FIG. 1)
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 entitled `Immune activation and HIV infection` is a schematic diagram to show how an HIV infected CD4+ cell activates other CD4+ and CD8+ cells by the presentation of VHP on MHC molecules. The minority of CD4+ cells activated by this process are then infected by HIV while the majority of CD4+ T cells become over stimulated and die.
Some of the activated CD8+ T cells are autoreactive and activate an autoimmune process which kills or suppresses activated T cells expressing HEP. The administration of HEP1 blocks the HIV induced T cell activation process and inhibits chronic HIV infection.
FIG. 2 entitled `Inhibition of HIV by Orally Administered HEP1 in vivo in patient PP` is a graphical representation of the normalised clinical trial data in Example 2 (data rebased to 100 on day 1 of the trial). The graph shows the result of oral administration of HEP1: the decline in HIV virus particles as measured by p24Ag levels, the decline in HIV infectivity as measured by a TCID assay and the fall in total white count (decline in immune activation).
FIG. 3 entitled `Improvement of Immune Status by Subcutaneously Administered HEP1 in vivo in patient PP` is a graphical representation of the normalised clinical trial data in Example 2 (data rebased to 100 on day 1 of the trial). The graph shows the result of subcutaneous administration of one larger dose of HEP1: a sharp increase in CD4+ and CD8+ T cells.
BRIEF DESCRIPTION OF THE SEQUENCES
SEQ ID NO. 1 is an amino acid sequence of a peptide according to the present invention.
SEQ ID NO. 2 is an amino acid sequence of a peptide according to the present invention.
SEQ ID NO. 3 is an amino acid sequence of a peptide according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Induction of immune tolerance with HEP1 related peptides and the prevention and treatment of AIDS
The non-obvious similarities between the HIV amino acid sequence;
NH 2 ThrLysAlaLysArgArgValValGluArgGluLysArgCOOH(SEQ ID NO. 1),
position 498 to 510 (conserved C4 region) at the C-terminus of HIV gp120 (VHP1) and sequences in human proteins, were investigated using computer searches of the SwissProt protein sequences database (Release 25). 1 established that VHP1 has a 70% sequence homology to an evolutionarily conserved human protein called ezrin between amino-acid positions 324-337 of ezrin. The result of the search for homology is set forth in the table below.
__________________________________________________________________________ HIV gp120-gp41 Cleavage site-X__________________________________________________________________________Position498 499 500 501 502 503 504 505 506 507 508 509 510gp120Thr Lys Ala Lys Arg Arg Val Val Glu Arg Glu Lys ArgHomology| | | | | | | | |EzrinThr Glu Lys Lys Arg Arg Glu Thr Val Glu Arg Glu Lys GluPosition324 325 326 327 328 329 330 331 332 333 334 335 336 337__________________________________________________________________________
I made the unexpected discovery that nine out of fourteen amino acids were identical when the HIV amino acid sequence between position 498 and 510 of gp120 was compared to the human amino acid sequence between positions 324 and 337 of ezrin. It is not obvious from prior publications that this region ezrin is important for immune regulation.
The fourteen amino acid sequence of HEP1,
NH 2 ThrGluLysLysArgArgGluThrValGluArgGluLysGIuCOOH(SEQ ID NO. 2),
is identical to the amino acid sequence between positions 324 and 337 of human ezrin. No publication had disclosed HEP1 related peptides in man.
Ezrin, a human tubulin binding protein, is found in the cytoplasm of T cells and is phosphorylated by tyrosine kinase during T cell activation. Ezrin is also known as P81, Cytovillin or Villin-2, is a protein of 585 amino acids. The homology extends over a predicted alpha-helical region of ezrin and is adjacent to the tyrosine 353 propoxylation site. Ezrin is part of a family of ezrin related proteins, which includes ezrin, radixin, moesin and merlin. All these proteins are related in the region that shows similarity to gp120, but ezrin has the most significant homology with 9/13 identities. Although ezrin behaves as a soluble protein in T cells and appears to be diffusely cytoplasmic by immunofluorescence staining, it is believed that the critical population of ezrin is that which is associated with the submembraneous cortical cytoskeleton (Identification of Ezrin as an 81-kDa Tyrosine-phosphorylated protein in T cells Egerton M., Burgess W. H., Chen D., Druker B. J., Bretscher A., Samelson L. E.The Journal of Immunology 1992 149: 1847-1852). It may also be important for the autoimmune pathology of AIDS that ezrin is also found localized to microvillar actin microfilament cores in the brush border of the intestinal epithelium and also in neurons. In the gut epithelium ezrin is involved in changes in cell membrane morphology in response to stimulation (Identification of the Two Major Epidermal Growth factor-induced Tyrosine Phosphorylation Sites in the Microvillar Core Protein Ezrin, Krieg J., Hunter T.,Journal of Biological Chemistry 1992 267: 19258-19265).
In addition to Ezrin, other human (self) proteins also possess a weaker primary sequence homology with VHP1: these include Heat shock protein 89, NK-TR protein, T complex protein, Adrenergic receptor Type 2, Creatine Kinase, Trypsin inhibitor, Aldehyde Dehydrogenase, Opioid Receptor (kappa), Glycine Receptor (Alpha-2 chain) and Ryanodine receptor. Mouse Histone H2B (very similar to human Histone H2B) also has homology.
It is an object of this invention that induction of tolerance can be used to switch-off immune activation and autoimmunity induced by HIV to prevent and treat HIV infection and AIDS. The present invention provides a vaccine against AIDS comprising a toleragenic dose (significantly larger than the threshhold dose sufficient to stimulate an immune response) of pharmaceutical grade purified peptide or a mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence with at least 50% homology over fourteen consecutive amino acids with HEP1 and a purified peptide or mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence of at least five consecutive amino acids with 100% homology with HEP1 or any combination thereof, or peptides similar thereto. The prefered route of administration is oral, although it is equally possible to achieve tolerance by sub-cutaneous, intravenous or intramuscular administration by standard methods. It is an aspect of this invention that a peptide vaccine based on HEP1 can be administered to prevent and treat AIDS in HIV infected people by the induction of tolerance to the VHP sequences. It is another aspect of this invention that a peptide vaccine based on HEP1 can be administered to prevent and treat SLE in people by the induction of tolerance to other HEP sequences.
HOW TO MAKE
Peptides used for the toleragenic vaccine may be synthesized, for example, using a solid phase method using either Boc or Fmoc chemistry or any other practical route for peptide synthesis known to those skilled in the art of peptide synthesis. After synthesis, peptides are cleaved from the resin (in solid phase methods) and deprotected using trifluoromethane sulphonic acid or Hydrogen Fluoride or other agents. Peptides may be desalted by column chromatography and purified by HPLC. Purity of the peptides may be demonstrated by reverse-phase HPLC or by automatic sequencing. Without limiting peptide or peptides either dissolved in sterile pharmaceutical saline or distilled water to a final concentation between 1 and 1000 mg/ml. The preparation may be freshly made up for each administration or may be stored frozen for up to 30 days at -20° C. (see EXAMPLE 1 & EXAMPLE 2).
HOW TO USE
The induction of immunological tolerance by oral administration or sub cutaneous administration of peptide solutions has been successfully achieved in various animal experiments. The immunological tolerance induced by peptides can occur either by induction of T cell anergy (direct inhibition) or by induction of suppressor T cell populations (indirect inhibition) by the peptides. Those skilled in the art of induction of immunological tolerance are aware of procedures to induce tolerance in animals by oral, sub-cutaneous, intravenous or intramuscular administration of small peptides derived from cross reactive antigens. Examples of these procedures have been disclosed in the following publications:
Could specific oral tolerance be a therapy for autoimmune disease, Stephen H., Thompson G., Staines N.A Immunol. Today 1990 11: 396-399
Induction of immunity and oral tolerance with polymorphic class II major histocompatibility complex allopeptides in the rat, Sayegh M. H., Khoury S. J., Hancock W. W., Weiner H. L., Carpenter C. B. Proc Natl Acad Sci USA 1992 89: 7762-7766
Oral tolerance in experimental autoimmune encephalomyelitis, Whitacre C C, Gienapp I. E., Orosz C. G.,Bitar D. M., The Journal of Immunology 1991 147 2155-2163
Prevention of experimental autoimmune myasthenia gravis by manipulation of the immune network with a complementary peptide for the acetylcholine receptor, Araga S., LeBoeuf R. D., Blalock J. E. Proc Natl Acad Sci 1993 90: 8747-8751
Peripheral T-cell tolerance induced in naive and primed mice by subcutaneous injection of peptides from the major cat allergen FeldI, Briner T. J., KuoM., Keating K. M., Rogers B. L., Greenstein J. L., Proc Natl Acad Sci 1993 90 7608-7612
Two factors are important for the induction of tolerance: high dose of soluble peptide antigen and absence of any co-stimulatory particles or adjuvant. Generally, immunological activation occurs with very much lower doses of peptide antigen than the threshhold dose above which the peptide antigen induces tolerance or inhibition of immune responses (for example in man a very small dose of 10 nanograms of a small foreign peptide antigen may illicite a strong immune response whereas a 10 milligram dose may inhibit the immune response). The dose range for the induction of tolerance varies between peptides but the amount or concentration may be determined experimentally. Subcutaneous administration of peptides yield final serum concentrations of peptide between 50-100× higher than by the oral route and therefore tolerance may be achieved with less peptide than by the oral route. The peptide solution should be filter sterilised to remove particulates and any microbiological contaminants, if a peptide solution is to be administered by injection.
It is an object of this invention that the preferred doses are between 1 mg and 5000 mg of pharmaceutical grade purified peptide or a mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence with at least 50% homology over fourteen consecutive amino acids with HEP1 and a purified peptide or mixture of two or more different peptides up to thirty amino acids long or derivative molecules with additional chemical groups attached to such peptides, comprising an amino acid sequence of at least five consecutive amino acids with 100% homology with HEP1 or any combination thereof, peptides similar thereto.
Although it is theoretically possible to attempt to induce immunological tolerance with peptides based on any HIV amino acid sequence, there is the general risk that a protective immune response against HIV may be inhibited. There is also a specific risk associated with administering peptides based on VHP1 to induce immunological tolerance as an incorrect dose of VHP1 based peptides may aggravate the disease by increasing immune activation. It is an advantage of this invention that the administration of peptides based on human amino acid sequences are likely to be significantly safer than peptides based on HIV amino acid sequences.
The following Examples serve to illustrate the invention only, and should not be construed as limiting it in any way.
EXAMPLE 1
IN VITRO MODEL OF VHP1-INDUCED AUTOIMMUNITY IN HUMAN CELLS FROM UNINFECTED DONORS.
MATERIALS and METHODS
Peptide synthesis
VHP1 peptide and control peptide used in this study were synthesized using a solid phase method using Fmoc chemistry. They were cleaved from the resin and deprotected using trifluoromethane sulphonic acid. Peptides were desalted on a P-10 column in PBS (pH 7.3). Homogeneity of the peptides was indicated by reverse-phase HPLC. Peptides were sequenced by automatic Edman degradation using gas phase sequence and were shown to be >95% pure. The following peptides were synthesised:
13 amino acid sequence of VHP1 derived from HIV:
NH 2 ThrLysAlaLysArgArgValValGluArgGIuLysArgCOOH(SEQ ID NO. 1)
A 14 amino acid control sequence:
NH 2 LeuGluAspArgArgAlaAlaValAspThrValCysArgAlaCOOH(SEQ ID NO. 3)
Donors
All donors who volunteered for this study were HIV negative. The MHC phenotype of donors was determined before the experiment. The number of the subtype of the A, B and C categories of MHC Class I phenotype and the number of the subtype of the DR, DP and DQ categories of MHC Class II phenotype of each donor is set out in the following tables:
______________________________________Donor A B C DR DP DQ______________________________________Donors positive for B8 or B35 (Trigger+)FM 1,3 8 7 3 nd ndSW 1,3 35,62 nd 1 nd 1WW 11,36 35,61 nd 1 nd 1JMC 1,2 8,45 6,7 3,4 nd 2,7Target 1 1 8 7 3 3 2Target 2 31 35 4 4 nd 7Donors negative for B8 or B35 (Trigger-)TM 3,28 7,14 nd 6 nd ndJF 2 17 3 6 nd 1KB 1 7,14 7 4,11 nd 7ML 2 44,52 5 2 nd 1Target 3 3 27 1 1 nd 5______________________________________
Generation of VHP1 induced short-term cultures
Peripheral Blood Mononuclear Cells (PBMC) were isolated from 8 HIV seronegative individuals who volunteered as donors for the study. Four donors FM, SW, WW, JMC (Trigger+) were positive for either MHC B35 or B8 and four donors TM, JF, KB, ML (Trigger-) were negative for MHC B35 or B8. PBMC (10 6 /ml) from the each of the donors were incubated in the presence of VHP1 or control peptide at 100 ng/ml for 4-8 hours to produce Effector Cells. Irradiated autologous PBMC without VHP1 stimulation served as controls.
Cytotoxicity Assay
VHP1 induced short-term cultures of autoreactive T cells (Effector Cells) were assayed for cytotoxic activity against autologous PHA T cell blasts stimulated with 5 μg/ml PHA for 4-5 days at a concentration of 10 4 cells/well in the absence of either control or VHP1 peptide (Target Cells). 1-2×10 6 Target Cells were labeled with 250 mCi of 51 Cr in 0.3 ml of medium for 1 hour at 37° C. Target cells were washed 3× in medium, diluted to 10 5 or 10 4 cells/ml and 100 ml of cell suspension added to each well of a V-bottomed 96-well microtitre plate. Effector Cells were added to the Target Cells at Effector:Target (E:T) ratios from 50:1 to 6.25:1. Cultures were incubated for 4 hours at 37° C. and supernatants were harvested and counted for 51 Cr release. Percent cytotoxicity is calculated using the formula : 100- (experimental release-spontaneous release)/(maximum release-spontaneous release). Spontaneous release and maximum release were determined by incubating target cells in medium or 1.0% Triton ×-100 respectively. Results where calculated as means ± Standard Deviations (SD) of triplicate cultures and a positive result was scored above 20% specific lysis. The cytotoxicity assay was repeated for allogeneic Target cells from donors (Target-1, Target-2 and Target-3) and the percent specific lysis scored at an Effector:Target ratio of 10:1.
T cell Proliferation Assay
The proliferation assays was performed by culturing either PBMC or T cell lines (10 4 cells/well) in U-bottomed 96-well microtitre plates for 3 days at 37° C. stimulated with fresh irradiated autologous PBMC and r-IL2 either with or without 1 μM VHP1. PBMC or T cell lines were rested in the absence of r-IL2 for 24 hours prior to assay. Three positive control cultures of the PBMC or T cell lines were stimulated with 10 μg/ml PHA, 10 μg/ml PPD and 0.1 μg/ml SEB (Staph. Enterotoxin) respectively to determine maximum proliferation. The two negative controls were an unstimulated culture of PBMC or T cell line and irradiated PBMC or T cell line under the same conditions. During the final 6 hours before harvesting, the cultures received 1 mCu/well of 3 H! thymidine. The cells were harvested onto glass fibre filters by a semiautomatic harvester and the incorporation of labeled thymidine was quantitated by liquid scintillation spectrometry. The results are expressed as counts per minute (cpm) of the mean for triplicate cultures.
RESULTS
Induction of autoreactive cells by VHP1
Short term cultures of PBMC from donors positive for B8 or B35 (trigger+) stimulated with VHP1 produced Effectors which showed significant autocytoxic responses against activated autologous T cell targets in the Cr release cytoxicity assays. Short term cultures of PBMC from donors positive for B8 or B35 stimulated with control peptide (Control) and short term cultures of PBMC from donors negative for B8 or B35 (trigger-) did not produce significant levels these autocytotoxic Effectors. The dependence of autocytotoxic responses on MHC phenotype of uninfected donors in short term cultures of PBMC stimulated with VHP1 is shown below.
Dependence of autoreactive response to VHP1 on MHC Phenotype of Donor
______________________________________ Peptide stimulantDONOR VHP1 Control______________________________________Trigger+FM + -SW + -WW + -JMC + -Trigger-TM - -JF - -KB - -ML - -______________________________________
Identification of the Target of VHP1 Induced Autoreactive Cells
To establish the MHC specificity of the cytotoxic cells stimulated by VHP1, further Cytotoxicity Assays with allogeneic PHA activated T cell Targets with different MHC phenotypes were then performed. The Effectors were derived from short term cultures of PBMC from donors of either MHC B8 or B35 (trigger+) incubated with VHP1 for 4-8 hours. The Target Cells were from donors with either B8 B35 (trigger+) or B27(Trigger-) MHC phenotype. Target PBMC incubated with radioactive 51 Cr for one hour before being mixed with Effectors. Effector Cells were mixed with radiolabelled Target Cells and incubated for 4 hours and lysis was measured by release of radioactive 51 Cr.
______________________________________Donor MHC Phenotype Predicted Sensitivity to AIDS______________________________________EFFECTORSJMC B8 HighWW B35 HighSW B35 HighTARGETS1 B8 High2 B35 High3 B27 Low______________________________________
The measurement of percent specific lysis by 51 Cr release at an Effector to Target Ratio of 10:1.
______________________________________Targets Effectors (Donor-MHC)(Donor-MHC) JMC-B8 WW-B35 SW-B35______________________________________Target1-B8 30 30 9Target2-B35 30 32 10Target3-B27 7 14 2______________________________________
JMC-B8 Effectors efficiently hit both B8 and B35 Targets but not B27 Targets. WW-B35 Effectors efficiently hit both B8 and B35 Targets but not B27 Targets (the same specificity as the JMC-B8 Effectors). SW-B35 Effectors showed a similar pattern of specificity in that they recognised both B8 and B35 Targets but not B27 Targets but the overall cytotoxic activity from this donor was lower.
B8 and B35 both have the identical trigger amino acid sequence in the alpha-one domain of MHC Class I whereas B27 has a different sequence.(GB 9411534.2 filed by Holms R. D, on 8th Jun. 1994). B8 and B35 phenotypes have been associated with high sensitivity to the development of AIDS alter HIV infection in a number of clinical studies. I conclude that VHP1 is presented by MHC Class I B8 and B35 to Effector T cells in the short term cultures of PBMCs. I also conclude that the TCR of B8 and B35 Effector T cells are recognising a common epitope on MHC Class I B8 and B35 of the Targets which is absent on MHC Class I B27. The common epitope is likely to be a combination of the common MHC Class I B trigger sequence (present in the alpha one domain of both B8 and B35 but not on B27) plus human peptides resembling HEP1 (self peptides homologous to VHP1).
An autoreactive T cell line was established from donor WW (HLA-B35 phenotype) by stimulation with VHP1. The line was a mixed population of 59% CD4+T cells and 28% CD8+T cells. A proliferation assay was performed to measure to level of proliferation in the T cell line to autologous (self) cells. T cell line WW responded vigorously to autoantigens presented on autologous irradiated PBMC at similar levels to the PHA or PPD stimulated positive control cultures.
Discussion
I conclude that VHP1 (at low concentrations) activates the immune system and induces significant levels of autocytotoxic cells in donors with MHC phenotypes associated with sensitivity to developing AIDS rapidly (B8 or B35) while it is not so active in donors who do not carry the MHC phenotypes associated with sensitivity to rapid development of AIDS. The correlation between VHP1 sensitivity and sensitivity to rapid development of AIDS suggests that the expression and correct presentation of the VHP1 sequence in HIV infected people may be an important step in the disease process which leads to AIDS.
EXAMPLE 2
CLINICAL TRIAL OF HEP1 IN AN HIV INFECTED PATIENT
The objective of this study was to determine in an HIV infected patient if the induction of immunological tolerance to HEP1 could reduce immune activation and HIV infection. The design of the first clinical experiment was to orally administer HEP1 to the patient in daily 10 mg doses (the lower end of the preferred dose range). This was then followed approximately three months later with a subcutaneous administration of HEP1 at a higher dose of 140 mg. To assess the therapeutic benefit of HEP1, the following disease progression markers were measured by taking blood samples before, during and after each trial and determining: HIV levels by a p24 antigen assay, HIV infectivity by a cellular TCID assay and immune activation by quantitating levels of various lymphocytes.
The Patient
Patient PP volunteered to take peptide HEP1 orally while attending the HIV Clinic at Ealing Hospital NHS Trust. Patient PP is a white male, 32 years old and has been HIV infected for eight years and entered the trail with a T cell count of 80 cells / mm 3 . He had not taken any anti-viral therapy (for example AZT) in the previous five years before the trial. At the time of the trial, the patient was HCV negative (Abbott 2nd generation), HepB negative and Blood group A rhesus (D) positive.
Synthesis of HEP1 peptide
Abbreviations
DCC--Dicyclohexylcarbodiimide
DIC--Diisopropylcarbodiimide
DCM--Dichloromethane
DMF--Dimethylformamide
TFA--Trifluoroacetic acid
Boc--t-Butlyoxycarbonyl-
HOBT--Hydroxybenzotriazole
DIEA--Diisopropylethylamine
DCU--Dicyclohexylurea
HF--Hydrogen Fluoride
370 mg of HEP1 (a 14 amino acid peptide) was synthesized by Boc-synthesis based on a human ezrin sequence: NH2ThrGluLysLysArgArgGluThrValGluArgGluLysGluCOOH (SEQ ID NO. 2). 0.05 mmole resin (Boc-aminoacid -OCH 2 pam resin) and a three fold excess of activated Boc-aminoacid solution (activated with 0.5M HBTU in DMF and 2.5 mmole DIEA) were coupled in the following steps. The resin was washed with DMF, Boc protecting groups removed with 100% TFA, the reaction was drained, flow washed with DMF for one minute, drained, activated amino acid solution was added, shaken for 10 minutes at room temperature then washed and the sequence of steps repeated for the next amino acid. On completion of the synthesis, the reaction mixture was flow washed with DMF, then with DCM and dried. The peptide was then cleaved from the resin with HF (-5° C. for 1.5 hours), the HF was evaporated, the mixture was washed with 5 ml ether and evaporated then the peptide dissolved in 6M guanidine 0.1M TRIS for HPLC preparative separation. After separation, the peptide was analysed for purity by HPLC and was determined to be over 99% pure HEP1. The peptide solution was then evaporated to a pure white fluffy solid under vacuum.
Preparation of HEP1 peptide for Oral Administration.
To a vial containing 221 mg of pure freeze dried HEP1 peptide approximately 5 ml of sterile distilled water was added to dissolve the peptide and the solution was washed into a 50 ml volumetric flask and made up to exactly 50 ml in the volumetric flask with more sterile distilled water giving a final concentration of 4.42 mg/ml HEP1. 2.26 ml volumes of the solution were transferred into twenty two separate lots in 5 ml plastic tubes and stored at -20° C. (10 mg of peptide per tube). Two vials were stored at -70° C. as reference solutions at the clinic and the remaining 20 vials were provided to the patient on dry ice in a vacuum flask. The vials were stored until use by the patient in a freezer at -20° C. The patient thawed out one tube (leaving the remaining tubes frozen in the Freezer) each morning and swallowed the solution one hour before breakfast. The procedure was repeated for twenty days.
Preparation of HEP1 peptide for Subcutaneous Administration.
HEP1 was administered subcutaneously to patient PP three months after the end of the oral administration study.
Preparation
To a vial containing 147 mg of pure freeze dried HEP1 peptide (no inorganic salts added) 1 ml of sterile distilled water was added to the vial to dissolve the peptide giving a final concentration of 147 mg/ml HEP1. The solution was filter sterilised through a 0.2 micrometer sartorius filter attached to a steril 5 ml syringe and then transfered a 5 ml sterile container.
Cellular TCID Assay
Cellular TCID is a technique that measures the relative amount of viral load within cells. Within four hours of a sample being taken from the HIV infected patient, 10 6 viable PBMC from the sample were obtained by centrifugation of the anticoagulated blood over Ficoll-Hypaque lymphocyte separation medium. A serial dilution of the patients cells was set up in a 24 well plate in decreasing amounts (1:1, 1:4, 1:16, 1:64 and 1:256 and a negative control using 0.9 ml special media (RPMI-1640) supplemented with 15% fetal calf serum and 10% interleukin 2. Infected cells were then cocultivated with 10 6 PBMC derived from an uninfected human donor that had been stimulated for 24-48 hours with phytohaemagglutin (PHA) to activate the cells to make them susceptible to infection by HIV. The cocultures were subsequently monitored for the presence of p24 antigen in the supernatant fluid twice weekly for up to 14 days, during this period the plates were spun on days 4,7,11 and 14 and then a 50% medium change was performed. The medium was removed at days 7 and 14 and saved in duplicate 0.5 ml eppendorff tubes (minimum 250 μl/tube) for future p24 antigen testing. The medium was removed on day 11 and any remaining medium from day 14 (after saving for p24 antigen testing) was pooled and stored in liquid nitrogen for future Virus culture. A culture was considered positive if the concentration of p24 antigen in the supernantant on day 7 and day 14 exceeded 30 picogram/ml (typical cut-off value). The lowest number of peripheral mononuclear cells required to produce a positive culture was taken as the end point and the reciprocal of the end point dilution indicated the relative number of infected cells in the patient.
p24Ag Assay
p24Ag is a marker of HIV infection as well as a predictor of HIV disease progression. The p24Ag assay measures p24 antigen from the core of HIV and is an immunoassay using murine monoclonal antibody coated onto microwell strips. The assay detects HIV in plasma, serum or tissue culture medium. If present, the antigen binds to the antibody-coated microwells. The bound antigen is recognised by biotinylated antibodies to HIV which react with conjugated strepavidin-horseradish peroxidase. Colour develops from the reaction of the peroxidase with hydrogen peroxidase in the presence of tetramethylbenzidine (TMB) substrate. Specimens which are HIV p24Ag positive can be quantitated by setting up a standard curve using serial dilutions of the Antigen Reagent. The assay is not accurate below 30 picograms per ml.
CD4, CD8, NK
T cell subsets were measured by adding a whole blood sample to a 4.5 ml tube containing EDTA and staining with monoclonal antibodies to CD3, CD4 and CD8. The percentage of T cells in Peripheral Blood Lymphocytes were determined by flow-cytometric procedures. The numbers of CD4 and CD8 T cells were determined by obtaining total and differential white-cell counts and multiplying by the appropriate factor obtained on flow cytometry.
Results: Oral Administration of HEP1
Blood samples were taken from the patient 69 days before the trial and on the first day of the trial before the first dose of HEP1, to determine the background levels of the disease progression markers. Oral administration of HEP1 solution containing 10 mg HEP1 was started on day 2 of the trial and continued until day 22. Further Blood samples were taken for analysis on day 7, day 14, day 21 and day 28 of the trial (7 days after the last dose of HEP1). The patient experienced no adverse reactions and continued to feel well through out the administration of HEP1.
The following markers of HIV disease progression were assayed: p24Ag (the concentration of HIV p24 protein in picogram/ml in the blood), TCID (the infectivity of the HIV in the cells of blood sample measured by an in vitro cell culture assay in which a serial dilution of the sample was mixed with activated uninfected PBMC and the level of HIV infection determined by p24Ag assay), total white count (immune activation measured by the number of white cells per mm 3 ), CD4 (the number of CD4 positive cells per mm 3 ), CD8 (the number of CD8 positive cells per mm 3 ), NK (the number of Natural Killer cells per mm 3 ), Lymphocytes (the number of cells per mm 3 ), Monocytes (the number of cells per mm 3 ), and Granulocytes (the number of cells per mm 3 ). Normalised data was calculated by dividing each data point by the value of its data series on day 1 of the trail and multiplying by 100.
______________________________________ BEFORE DURING TREATMENT TREATMENT AFTERTrial day day-69 day 1 day 7 day 14 day 21 day 28Date 3/11/94 10/1/95 17/1/95 24/1/95 1/2/95 7/2/95______________________________________p24Ag n/a 71 44 n/a n/a 38TCID n/a 1:16 n/a n/a n/a 1:1White count 7900 8200 8200 7700 6800 5500CD4 90 80 80 90 80 80CD8 850 900 850 900 910 730NK 20 30 30 40 40 20Lymphocytes 1260 1480 1150 1460 1160 1050Monocytes 630 570 490 620 540 440Granulocytes 6000 6230 6560 5620 5100 4020% Lym- 15.4 17.8 15.5 16.8 18.6 20phocytes% Monocytes 4.2 6.1 3.1 6.4 5.2 5.5% Granu- 80.4 76.1 81.4 76.8 76.2 74.5locytes______________________________________NORMALISED DATA- day 1 = 100Trial day day-69 day 1 day 7 day 14 day 21 day 28Date 3/11/94 10/1/95 17/1/95 24/1/95 1/2/95 7/2/95______________________________________p24Ag 100 62 54TCID 100 6White count 96 100 100 94 83 67CD4 113 100 100 113 100 100CD8 94 100 94 100 101 81NK 67 100 100 133 133 67Lymphocytes 85 100 78 99 78 71Monocytes 111 100 86 109 95 77Granulocytes 96 10 105 90 82 65% Lym- 87 100 87 94 104 112phocytes% Monocytes 96 100 51 105 85 90% Granu- 106 100 107 101 100 98locytes______________________________________
These preliminary clinical results show that orally administered HEP1 reduced viral load by 46% as measured by p24Ag, and reduced the infectivity of HIV by 16 X as measured by TCID and that the effect persisted for 7 days after treatment. It is important to note that the p24Ag level was only just above background at 38 picogram/ml as 30 picogram/ml is considered the typical cut-off value. The total white cell count was rising before treatment but fell during and after treatment suggesting a reduction in immune activation had been achieved during treatment. The persistance of these effects for seven days after treatment suggests that a T suppressor cell population had been induced in the patient which reduced infectivity of HIV and immune activation. CD8 increased during treatment but there was no significant increase in CD4 count (at this concentration of HEP1). (FIG. 2)
Results
Subcutaneous Administration of HEP1
0.95 ml (the volume equivalent to 14 mg HEP1) of the steril solution was self-injected subcutaneously in the abdomental wall in one dose on day 1 of the subcutaneous HEP1 trial. Patient PP experienced a stinging sensation which lasted approximately 15 minutes but there were no other adverse reactions. Blood samples were taken on day-92, day-57, day-8, day 1 before the HEP1 injection and day 1 * four hours after the injection and then 6 days and 13 days after the HEP1 injection. The samples were assayed for p24, TCID, CD4, CD8, total white count, lymphocytes, granulocytes, monocytes and the data is set out in the table below (normalised data was calculated as described above).
______________________________________ End Oral BEFORE study TREATMENT AFTERTrial day day-91 day-56 day-7 day 1 day 1* day 6Date 7/2/95 14/3/95 2/5/95 9/5/95 10/5/95 16/5/95______________________________________p24Ag 38 n/a n/a n/a n/a n/aTCID 1:1 n/a n/a n/a n/a n/aWhite count 5500 6600 8200 5600 4600 5400CD4 80 75 70 80 120 80CD8 730 880 670 880 1130 780NK 20 75 40 30 30Lymphocytes 1050 1250 980 1290 1520Monocytes 440 400 570 450 510Granulocytes 4020 4950 6640 3860 2530% Lym- 20 19 12.9 23.3 33 22.2phocytes% Monocytes 5.5 6 7 8 11% Granu- 74.5 75 81 69 55locytes______________________________________NORMALISED DATA- day 1 = 100Trial day day-91Date 7/2/95 day-56 day-7 day 1 day 1* day 6______________________________________p24Ag n/m n/a n/a n/a n/a n/aTCID n/m n/a n/a n/a n/a n/aWhite count 98 118 146 100 82 96CD4 100 94 88 100 150 100CD8 83 100 76 100 128 89NK 67 250 133 100 267Lymphocytes 81 97 76 100 118Monocytes 98 89 127 100 113Granulocytes 104 128 172 100 66% Lym- 86 82 55 100 142phocytes% Monocytes 69 75 88 100 138% Granu- 108 109 117 100 80locytes______________________________________
The subcutaneous administration of one larger dose of HEP1 resulted in a sharp rise in both CD4 T cells (+50%) and CD8 T cells (+28%) after the HEP1 injection followed by a return to the pre-injection i levels six days later (p24Ag and TCID data was not ready in time for the filing of the application). (FIG. 3)
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 3(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 13 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:ThrLysAlaLysArgArgValValGluArgGluLysArg1510(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 14 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:ThrGluLysLysArgArgGluThrValGluArgGluLysGlu1510(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 14 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:LeuGluAspArgArgAlaAlaValAspThrValCysArgAla1510__________________________________________________________________________ | It is an object of the present invention to provide preparations for the treatment or prophylaxis of AIDS and systemic lupus erythematosus and related disorders. The invention is based on the discovery of the process triggered in the immune system by HIV which leads to AIDS. HIV has a specific mechanism to activate the immune system to allow it to replicate and this same immune activation leads to an autoimmune process which eventually leads to AIDS. The preparation for treatment comprises novel synthesized peptides whose amino acid sequences are derived from a human protein called ezrin and are based on the following sequence: NH 2 ThrGluLysLysArgArgGluThrValGluArgGluLysGluCOOH SEQ ID. No. 2. The mechanism of action of these peptides is that they switch off specific retrovirally induced immune responses by immunological tolerance. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not Applicable.
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] This invention relates to an auxiliary torso top outer garment to be worn by women wearing revealing bathing suits, primarily bikinis, during activities other than sunbathing.
[0006] 2. Prior Art
[0007] Women that are fashionable and desirous of tanning much of their bodies when lying on the beach or poolside often wear bikini bathing suits to minimize tan lines on their backs, necks and elsewhere. This usually presents no problem when sitting or lying still on a towel or chaise lounge or the like. However, when bikini-clad women actively move about, playing volleyball, swimming, playing with and/or attending to children, where they may need to bend at the waist and/or crawl on the sand, the fashionable bikini tops pose risks of the breasts “popping out” of the bikini tops and/or being overly exposed.
[0008] Currently, the available possible solution to this problem is to buy and wear a sports bra or triathlon styled top where the shoulder straps merge into a one piece central leg forming a “Y” shaped back member by which unwanted tan lines would be made on the back of a woman wearing same. Other sports bras have shoulder straps connected to a wide torso band at the back, which would be unwanted by a woman wearing a bikini top. Not only do sports bras cover too much of the torso, but the fabric is much thicker than bathing suit material and they are more binding and uncomfortable to wear. Also, to put on a sports bra over a bikini top while on the beach or at poolside would present some difficulties in properly positioning the sports bra and/or the underlying bikini top.
[0009] Accordingly, this invention seeks to overcome the above problems by providing a cover up in the form of an auxiliary torso top outer garment which is readily donned and doffed without the normal motions of the bikini top wearer in attempting to also put on a sports bra over the bikini top being worn. Women using the torso top outer garment would normally preset the adjustable straps of the torso top outer garment in the privacy of their own home or hotel room, for example, over their bikini tops so that the auxiliary torso top outer garment would be preset and ready to be put on, much like a bolero or short jacket with a simple front closure, such as an open ended zipper.
[0010] Another feature of the auxiliary torso top outer garment is that it should provide the wearer with comfort and support so that it may be worn comfortably for extended periods of time if necessary without detracting from the ability to obtain a tan over most of the back of the wearer and which looks more stylish than sports bras and can withstand repeated washings, wetting and drying substantially like a swimsuit.
SUMMARY OF THE INVENTION
[0011] The torso top outer garment in accord with this invention provides increased coverage and support for women wearing bikini bra swimsuits, and the garment includes right and left side front portions respectively having a generally horizontal lower edge and a generally vertical edge extending perpendicular and upward from an end of said lower edge. The side front portions are made of a stretchable outer fabric for swimsuits that stretches vertically and horizontally and side front portions have a stretchable inner fabric that lines the outer fabric and also stretches vertically and horizontally. Both of the fabrics are thin and readily dry after being wet. An open-ended front zipper of a predetermined length is attached to each of the right and left side front portions along the vertical edges for releasably securing the right and front side portion to said left side front portion. A length of elastic material of a predetermined width is disposed along each of the lower edges and located between the inner and outer fabric within a casing formed between the opposite ends of the lower edge and having a length shorter than the lower edge, the elastic material having ends secured to respective side front portions to provide gathers of the fabrics along the lower edge. Each of the side front portions having a slightly curved elongated neck edge connected to respective upper ends of the vertical edges at one end of the neck edge and having another end spaced away a predetermined distance. Each of the side front portions has a greater curved elongated arm edge with opposite ends one end thereof being adjacent another end of the neck edge and another arm edge end being adjacent another end of the lower edge. An elongated neck strap connects and spans between another end of the neck edge of the right and left front portions, and an elongated back strap connects and spans between another end of the arm edge of the right and left front portions.
[0012] Other aspects of the invention are seen in the neck strap being adjustable in length and includes a length of elastic material. The neck strap carries a closed slide by which the elastic material is effectively shortened to substantially have overlapping parts and by which the elastic material is effectively lengthened to substantially have non-overlapping parts.
[0013] Additional aspects are provided by the back strap being adjustable in length and includes a length of elastic material. The back strap carries a closed slide by which the elastic material is effectively shortened to substantially have overlapping parts and by which the elastic material is effectively lengthened to substantially have non-overlapping parts.
[0014] Further aspects are provided by forming attachment zones for securing the back strap by another end of the lower edge and another arm edge end of each of the side front portions. Attachment zones are formed for securing the neck strap by another end of the neck edge and the one end of the arm edge of each of the side front portions.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0015] The novel features which are believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings, in which:
[0016] FIG. 1 is an outer front elevational view of the auxiliary torso top outer garment in accord with the invention showing the open-ended front zipper, the adjustable neck strap and the adjustable back strap;
[0017] FIG. 2 is an inner front elevational view of the right side portion of the garment of FIG. 1 , as viewed from inside the garment, without the major portion of the neck and back straps;
[0018] FIG. 3 is an inner front elevational view of the left side portion of the garment of FIG. 1 , as viewed from inside the garment, without the major portion of the neck and back straps; and
[0019] FIG. 4 is an outer front elevational view of another embodiment of the auxiliary torso top outer garment in accord with the invention, with modified adjustable neck and back straps.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The auxiliary torso top outer garment is generally designated by numeral 10 in FIG. 1 , and includes a right side breast portion 12 and a left side breast portion 14 releasably secured together by an open-ended front zipper 16 having an insertion pin 18 , a retainer box 20 mounted at the bottom 21 of left side of the zipper tape 22 , as shown in FIG. 3 . The top stop 23 is on the right side of the zipper tape 24 , as shown in FIG. 2 , and is spaced from insertion pin 18 . Stop 23 and pin 18 are disposed at opposite ends of the zipper tape 24 , as sewn into the garment 10 . The zipper slider 25 has a pull tab 26 movably connected to the slider 25 so that it may assume the position shown in FIG. 1 or be folded 180° downwardly to lie against the slider 25 and some of the interlocking fasteners 27 and 28 on respective tapes 24 and 22 , all of which are well known to those having ordinary skill in the art.
[0021] The tapes 22 and 24 are sewn as depicted by broken lines 30 and 31 in respective FIGS. 2 and 3 to the completely lined bathing suit fabric of nylon Lycra spandex or the like which may be 80 or 90% nylon and 20 or 10% Lycra spandex and usually with four way stretch, as known in the art of swimsuits.
[0022] The upper edge 32 of each breast portion 12 and 14 has a shallow curve to form a U-neck or may be straighter to form a V-neck and has a length of about 7″ to 8″. The bottom edge 29 is gathered and has a length of about 9″ to 10″. The more deeply curved edge 33 is about 12″ to 13″. The breast portions 12 and 14 are sewingly connected to short casing end attachment zones 41 and 44 respectively, forming parts of neck strap 39 and back strap 42 . Spanning between attachment zone 41 is an adjustable elastic strap 40 which is adjusted to the minimum length, as shown with the elastic being doubled, and may be adjusted to its maximum singled length by a closed slider 46 , commonly found on adjustable bra shoulder straps and the like. Likewise, casing end attachment zones 44 of the back strap 42 are connected to doubled elastic 43 and the back strap 42 is provided with a closed slider 48 .
[0023] A typical torso top outer garment when sewn in accord with this invention may have the following attributes:
A. zipper 16 —length 5″ to 6″ B. side breast portion 12 and 14 unstretched bottom length—9″
stretched bottom length—13″
C. elastic 34 width ½″ sewn at ends by sew lines 35 and 36 to create gathers 37 in the casing 38 between the inner and outer fabric forming the fully lined garment D. unstretched upper edge 32 length—8″
stretched upper edge 32 length—11″
E. unstretched side curved edge 33 length—15″
stretched side curved edge 33 length—20″
F. neck strap 39 with unstretched elastic 40 doubled—12″
stretched elastic 40 doubled—16″ elastic 40 single stretched—21″ width of elastic 40 —¾″
G. back strap 42 with unstretched elastic 43 doubled—11″
stretched elastic 43 doubled—16″ elastic 43 single stretched—22″
H. elastic 40 doubled about 3″ and connected to end attachment zones 41 by respective closed slide 46 and side open slide 47 I. elastic 43 doubled about 3″ and connected to end attachment zones 44 by respective closed slide 48 and side open slide 49
[0041] Preferably, the upper edge 32 of each breast portion 12 and 14 is provided with elastic 52 sewn at ends by sew lines 53 and 54 to create gathers 55 in the casing 56 between the inner and outer fabric forming the fully lined garment 10 . Likewise the curved edge 33 of each breast portion 12 and 14 is provided with elastic 57 sewn at ends by sew lines 58 and 59 to create gathers 60 in the casing 61 between the inner and outer fabric forming the fully lined garment 10 .
[0042] It is to be understood that the width of the elastic 52 and/or 57 may be the same or differ to provide a comfortable fit around the breast of the wearer. Also, that the elastic 52 and/or 57 may be the same or differ from the width of elastic 40 and/or may be pre-stretched differently from the stretching of elastic 40 within its casing 38 .
[0043] Sliders 47 and 49 may be closed sliders like sliders 46 and 48 , or may be one side open sliders so that each or either of the neck strap 39 and back strap 42 may be opened to provide even greater versatility for the user in properly presetting the garment 10 in privacy.
[0044] With the above attributes, the drawings and the description, a person having ordinary skill in the sewing arts and particularly in the swimsuit sewing arts would be able to cut out, assemble and sew the auxiliary torso top outer garment 10 of this invention. It is intended that perhaps only two or perhaps three different sizes would be needed to adequately fit most women in a supportive and comfortable manner, such as,
Small—Medium, Large—Extra Large, and 2x-3x
[0048] The various adjustable features of the straps 39 and 42 and the stretchability of not only the elastics 40 and 43 (and 34 ) but the stretchability of the entire side breast portions 12 and 14 and casing attachments 41 and 44 , provide the garment with the ability of proper fitting of most women's upper torso over bikini tops.
[0049] As hereinbefore mentioned, the auxiliary torso top outer garment 10 would normally be adjusted by the bikini top wearer at the house or hotel prior to going to the beach or pool. She would remove the torso top outer garment 10 from her body after adjustments and would be ready to go to the beach or pool wearing her bikini bathing suit, perhaps exposing more of her skin, as many bikini tops do. Before swimming or playing volleyball, or running or overly bending or playing with and/or attending to her children, she would put on the auxiliary torso top outer garment 10 , which neatly and comfortably covers more of her breasts and would more effectively support and maintain the breasts inside the torso top 10 even if the breasts somehow “pop out” from the bikini top she is wearing. Likely this would not occur if the woman properly adjusted the auxiliary torso top outer garment 10 before she wore it over her bikini top
[0050] FIG. 4 depicts an alternate embodiment with most of the same components identified by the same numerals. The casing attachments 41 and 44 are substantially shortened or eliminated so that longer elastics 52 and 53 primarily and respectively form substantially the entire neck strap 39 A and back strap 42 A, as shown. Each of those straps 39 A and 42 A have corresponding respective closed slides 46 , 47 , 48 and 49 which function in the same manner as heretobefore described. This embodiment, while perhaps being more easily sewn and less costly, is not as comfortable to the wearer, as the embodiment of FIGS. 1-3 .
[0051] While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention. | A cover up torso top outer garment provides increased coverage and support for women wearing bikini bras formed of right and left side front stretchable portions of an outer fabric and an inner fabric with an open-ended front zipper releasably securing the portions, and elastic material along the bottom edge of each portion to form gathers along each bottom edge. Each portion has an elongated neck edge, and an elongate arm edge, with an elongated adjustable neck strap connected to the neck and arm edges of each portion, and an elongated adjustable back strap connected to the neck and bottom edges of each portion. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 12/546,377, filed on Aug. 24, 2009, which is a continuation of U.S. patent application Ser. No. 11/868,406, filed on Oct. 5, 2007, now U.S. Pat. No. 7,597,456, which is a division of U.S. patent application Ser. No. 10/893,727, filed on Jul. 16, 2004, now U.S. Pat. No. 7,296,913, which claims priority to and the benefit of U.S. Provisional Patent Application No. 60/517,130, filed on Nov. 4, 2003. The entire disclosure of each of these applications is hereby incorporated herein by reference.
TECHNICAL FIELD
[0002] In various embodiments, the present invention relates generally to illumination systems and methods incorporating light emitting diodes (LEDs), and more specifically to such systems and methods that provide both direct illumination and decorative illumination.
BACKGROUND
[0003] Currently lighting applications are dominated by incandescent lighting products. Because they use hot filaments, these products produce considerable heat, which is wasted, in addition to visible light that is desired. Halogen-based lighting enables filaments to operate at a higher temperature without premature failure, but again considerable non-visible infrared light is emitted, and this heat is directed away from the lamp to the extent feasible. This is conventionally done by using a dichroic reflector shade that preferentially passes the infrared as well as a portion of the visible light. The nature of this dichroic reflector is such that it passes several different visible colors as well as the infrared radiation, giving a somewhat pleasing appearance. This has led to numerous decorative applications for such halogen lights. These lights consume substantial current and dissipate considerable unwanted heat. Halogen bulbs are designed to operate at a variety of voltages between 12 volts (V) to as high 15 V or greater.
[0004] Light emitting diodes have operating advantages compared to ordinary incandescent and halogen lights. LEDs typically emit a narrow range of wavelengths, thereby eliminating, to a large degree, wasted non-visible energy. White light can be created by combining light colors. LEDs can also emit in the ultraviolet wavelength range, in which case white light (as well as certain colors) can be created by excitation of a phosphor.
[0005] LEDs have an extremely long life compared to incandescent and halogen bulbs. Whereas incandescent and halogen bulbs may have a life expectancy of 2000 hours before the filament fails, LEDs may last as long as 100,000 hours, and 5,000 hours is fairly typical. Moreover, unlike incandescent and halogen bulbs, LEDs are not shock-sensitive and can withstand large forces without failure, while the hot filament of an incandescent or halogen bulb is prone to rupture.
[0006] Halogen bulbs, incandescent bulbs, and LEDs all typically require a fixed operating voltage and current for optimal performance. Too high an operating voltage causes premature failure, while too low an operating voltage or current reduces light output. Also, the color of incandescent and halogen lights shifts toward the red end of the visible spectrum as current and voltage are reduced. This is in contrast to LEDs, in which only the intensity of the light is reduced. Furthermore, as the voltage to an incandescent or halogen light is reduced, its temperature drops; as a result, its internal resistance decreases, leading to higher current consumption but without commensurate light output. In cases where batteries are used as the source of energy, they can be drained without producing visible light.
[0007] Incandescent and halogen bulbs require a substantial volume of space to contain the vacuum required to prevent air from destroying the filament, to keep the glass or silica envelope from overheating, and to insulate nearby objects from the emitted heat. In contrast, LEDs, as solid-state devices, require much less space and generate much less heat. If the volume of an incandescent or halogen bulb is allocated to a solid-state LED light, considerably more functions may be incorporated into the lighting product.
[0008] Unlike incandescent and halogen lights, LEDs ordinarily produce light in a narrow, well-defined beam. While this is desirable for many applications, the broad-area illumination afforded by incandescent and halogen lights is also often preferred. This is not easily accomplished using LEDs. The light produced by incandescent and halogen lights that is not directed towards the target performs a useful function by providing ancillary illumination and a decorative function. Halogen lights with their dichroic reflectors do this necessarily, but ordinary incandescent lights can employ external shades, not part of the light bulb, in a variety of artistic designs to make use of this otherwise misdirected light.
SUMMARY
[0009] Embodiments of the present invention overcome the limitations of halogen or incandescent light sources, and combine their desirable properties with the advantages afforded by LEDs into a unique system. Various embodiments include systems and methods that provide direct illumination as well as decorative illumination distinct from the direct illumination.
[0010] Embodiments of the present invention therefore include an LED-based light emitter (which includes one or more LEDs) for replacing standard incandescent and halogen bulbs for a wide variety of purposes. In accordance with various embodiments, lighting systems have enhanced functionality compared to that of conventional incandescent- or halogen-based lighting systems, and typically include a decorative illumination element that provides, e.g., decorative illumination distinct from the direct illumination from the light emitter.
[0011] Some embodiments include an electrical connector or base the same as or equivalent to a standard bulb base, a printed circuit board (or other circuit substrate or module) electrically connected to the base, a driving circuit that may be mounted on or embodied by the printed circuit board, and/or one or more LEDs of one or more colors that may be attached to the printed circuit board. The driving circuit may include or consist essentially of a solid-state circuit that regulates the voltage and current available from the electrical source (e.g., a power socket) and regulates the output to a constant value utilized by the LEDs. The available source voltage may be either greater than or less than that utilized by the LEDs.
[0012] Various embodiments of the present invention include an LED lamp that replaces incandescent and/or halogen lamps as well as their decorative shades by including LEDs on both sides of the printed circuit (PC) board, where the decorative LEDs may be on the opposite side of that intended for direct illumination. The decorative LEDs may, for example, illuminate an envelope or shade around the lamp.
[0013] Lighting systems in accordance with various embodiments may also include additional circuitry, e.g., to allow remote control of lighting functions via an infrared or wireless device; to change the color of either or both of the (decorative) shade illumination and the direct-illumination LEDs; to impart a time-varying color and/or intensity to the (decorative) shade illumination and/or the direct illumination; to enable external switching via mechanical action of color, pattern, and/or intensity on either the shade or direct illumination; and/or to enable the switching of the various functions of color, intensity, and/or pattern by interrupting the power to the circuit within a predetermined time interval.
[0014] Mechanisms such as mechanical actuators that alter the pattern and color of light to the shade for the purpose of decorative illumination may also be included. Such mechanisms may be or include a shadow screen, a multi-faceted mirror, or other reflective or diffractive optical component or components either fixed within the envelope of the lighting unit or which are configured to move in order to vary the pattern and/or color of the resulting light for decorative and/or direct-illumination purposes.
[0015] Various embodiments of the present invention feature one or more additional light emitters such as LEDs disposed within the envelope (housing) of the light bulb to provide the decorative illumination. A separate, secondary circuit may be used to produce a constant current for the additional, decorative light emitter(s) and control their decorative illumination characteristics such as intensity, color, pattern, and/or frequency. The secondary circuit may be connected to the main source of power. Light generated from the decorative light emitter(s) may be guided along at least a portion of the length of an optical component and exit the housing through openings on the shade of the housing. Such embodiments may include a secondary optical element to direct light generated by the light emitter for direct illumination (e.g., the primary-illumination LED(s)) to provide the decorative illumination. A heat sink may be thermally connected to any or all of the light emitters for regulation of their temperature. A circuit may provide remote control of lighting functions of the lighting system (e.g., the decorative light emitter(s)) via, e.g., an infrared or wireless device.
[0016] One or more optical components may be disposed within the housing, and may direct a first, larger (e.g., more intense) portion of light generated by the light emitter(s) for direct illumination and direct a second, smaller (e.g., less intense) portion of light for decorative illumination. The second portion of light may be guided along the length of a secondary optical component and exit the housing through one or more openings on the shade of the housing. In an alternative embodiment, the decorative illumination is achieved by light emission through a plurality of light paths connecting the housing and the optical component that directs the second portion of light from the light emitter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] 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 drawing, in which:
[0018] FIG. 1 illustrates various views of an exemplary halogen illumination device referred to commonly as an MR-16.
[0019] FIG. 2 illustrates various view of an embodiment of the present invention that can retrofit the halogen illumination device and contains LEDs for illumination on one side and LEDs for direct illumination on the other. Circuitry to enable regulation and other features is also shown.
[0020] FIG. 3 illustrates various views of an embodiment of the present invention in which high intensity LEDs are placed on both sides to produce shade illumination and direct illumination. A switch and circuitry for changing the attributes of the lighting is also shown.
[0021] FIG. 4 illustrates various views of another embodiment of the present invention in which a movable, multifaceted mirror is included on the shade side of the illumination unit to provide a variable pattern on the shade.
[0022] FIG. 5A illustrates various views of another embodiment of the present invention in which an internal fixture containing apertures is included to pattern illumination to the shade.
[0023] FIG. 5B is a sectional view of another embodiment of the present invention in which an additional LED is disposed within the housing to produce decorative illumination.
[0024] FIG. 5C is a sectional view of another embodiment of the present invention in which decorative illumination arises from an optical component that directs light generated from the primary light emitter.
[0025] FIG. 5D is a sectional view of another embodiment of the present invention in which a plurality of the light paths, connecting the housing and the optical component, direct a portion of the light from the primary light emitter for decorative illumination.
[0026] FIG. 6 shows elevational and top views of a means for producing a series/parallel circuit comprised of individual LED semiconductor chips on a circuit board that results in a high-density lighting array.
[0027] FIG. 7 shows elevational and top views of an embodiment of the high-density LED array coupled with an integrated lens array that is movable to produce variable-directional lighting.
[0028] FIGS. 8( a ) and 8 ( b ) schematically illustrate a constant-current implementation of a compact dc/dc boost converter with a feature that enables current regulation of LEDs based on the thermal environment.
[0029] FIGS. 9( a ) and 9 ( b ) schematically illustrate a compact constant-current buck/boost circuit for current regulation based on the thermal environment in accordance with various embodiments of the invention.
DETAILED DESCRIPTION
[0030] FIG. 1 illustrates an incandescent halogen-type bulb commonly available. The features of this bulb derive from its operating characteristics: it operates at high temperatures; it requires an evacuated envelope separated from the hot filament; it emits large quantities of infrared radiation experienced by the user as heat; and it consumes large quantities of electrical power. Nonetheless, these devices are in common usage and fixtures and appliances have been constructed to accommodate the form, fit, and function of these bulbs. This particular unit is a model MR-16.
[0031] The essential components of the bulb include a connector 101 that attaches to a standard source of electrical power (e.g., a power socket) that has a mating adapter; an evacuated transparent capsule 102 containing the hot filament 105 ; an envelope 103 that acts as a shade and filter to allow infrared radiation to pass, while reflecting a portion of the desirable visible light to the objects below; and a transparent front cover 104 that allows the radiation to pass, while protecting the evacuated capsule 102 from breakage.
[0032] FIG. 2 illustrates an embodiment of the current invention. This illuminating device preferably has the same form, fit and function as the incandescent illumination device of FIG. 1 and as such has a similar electrical connector 201 and similarly shaped transparent or translucent envelope 202 . The envelope 202 will generally act to scatter light emitted from inside the envelope and be visible from the outside. As such, the envelope 202 may serve as a screen onto which are projected and displayed images, colors or other decorative or information-containing light either visible to humans or at shorter or longer wavelengths. The decorative or informational content may be generated by circuitry contained on one or more circuit boards 206 within the envelope of the bulb 202 . This circuit 206 in its simplest form controls other illumination devices such as, e.g., the LEDs 207 located on the back of the circuit board 204 . Another circuit 205 may be used to control high-power LEDs 209 in an array 208 for direct illumination of objects outside the envelope of the lighting device. However, this circuit or circuits may enable several useful features, including (i) a timer to adjust the color and illumination level according to some preset or user-adjustable schedule, (ii) a photocell to turn the light on or off depending on the ambient light level and or a proximity sensor, (iii) a signaling function that communicates with other lights, and/or (iv) a user-accessible switch that enables switching of illumination characteristics such intensity, color, and/or continuous or flashing illumination modes.
[0033] Also typically located on circuit board 204 is a power-conditioning circuit 205 that regulates power to the high-intensity LEDs 208 located on the underside of the board. This circuit adapts and controls the power available via the connector 201 and conducted to the board via wires 203 . The circuit 205 may contain storage features including a battery to enable the lighting device to act as an emergency light source in the event of a power failure. The circuit may rectify AC power to DC to suit the desired current and voltage required by the series and/or parallel array of LEDs and provide power to other on-board circuitry.
[0034] In this embodiment, the LEDs 207 on the backside of the PC board 204 may serve the function of communication and/or decoration. For decorative purposes, the shade 202 is preferably made of a colored or white transparent (or preferably translucent) material such as plastic or glass that is textured to scatter light. In this manner light from the LEDs 207 impinges on this surface and is made more visible to the user, and may serve the function of decoration. The shade 202 may also contain penetrations 210 to allow heat to exit the LED enclosure.
[0035] FIG. 3 illustrates a similar incandescent replacement product. This product also contains an electrical connector 301 , a shaped translucent or transparent envelope 302 with holes 310 to remove heat, one or more printed circuit boards 304 within the enclosure, and means such as wires 303 to conduct electrical power to these board(s). This embodiment has high-intensity illumination LEDs 307 on the top surface and other high-intensity LEDs 309 in an array 308 on the bottom surface. Unlike the product of FIG. 2 , which had small LEDs with a narrow exit beam and low intensity, these high intensity LEDs 309 and 307 have a higher light output (generally greater than 10 lumens), and the exit angle of the light may range from a narrow angle to a very broad beam as desired. To control these LEDs, additional circuitry may be required as shown in the figure. In addition to the power-transforming circuit 305 and the control circuits 306 , additional power handling circuits 311 may be included. The high-power LEDs may have one or more colored light outputs other than white, and have different orientations other than vertical to provide decorative illumination above the lighting product. A switch 311 that is accessible by the user may be used to control characteristics of operation of the lighting product.
[0036] FIG. 4 illustrates another embodiment of the present invention. Unlike the previous examples in which modification of the color, intensity and pattern is performed by electrically controlling the electrical power to individual devices of one or more orientations and/or color, this embodiment contains a mechanical feature for varying the intensity and/or pattern with time. Variation is accomplished by, for example, a multi-faceted mirror 420 , operated by a miniature electric motor 421 that changes the orientation and position of the mirror. In this way light is reflected or diffracted to form a pattern of shapes and/or color on the translucent or transparent envelope 402 .
[0037] FIG. 5A illustrates another embodiment that includes a patterned mask 520 (or other suitable means) that casts a shadow or other predetermined pattern by blocking or otherwise modifying the pattern of light emanating from the internal LEDs 507 located on the back side of the circuit board 504 . Other features from other embodiments discussed herein may also be incorporated.
[0038] FIG. 5B illustrates another embodiment in which an additional, separate light emitter 531 (such as, e.g., one or more LEDs) is controlled and/or powered by a main illumination circuit 532 . The light emitter 531 may be coupled to separate and dedicated optics 533 to provide flexibility in design, as light emitter 531 is generally meant to provide decorative illumination that is distinct from and that complements the direct illumination from the primary illumination source 534 . For example, the decorative illumination may be different from the direct illumination at least in terms of illumination direction, color, and/or intensity. Power is provided via connection of a power connector 535 to an input power source, which, for example, may be either 115 VAC or 12 VAC. A circuit 532 is preferably used to convert the alternating voltage to an approximately constant DC current.
[0039] Light generated by the primary illumination source 534 may be directed by an optical component 536 (e.g., a total-internal-reflection (TIR) optic) and exit a substantially transparent cover 537 attached to the housing (envelope) 538 to provide direct illumination. Electrical connector (or circuit) 539 typically connects the light emitter 531 to the circuit 532 , which may produce a smaller constant current for the decorative light emitter 531 than that for the primary illumination source 534 . Electrical connector 539 may be connected to the main power source; it may include or consist essentially of a resistor that limits current to the decorative light emitter 531 and that is in parallel to the primary illumination source 534 . The circuit 539 may contain other suitable electronics that modulate or adjust the decorative illumination, such as the intensity, color, and/or frequency of the decorative light emitter 531 . The light from the decorative light emitter 531 may be emitted in substantially the same direction as light from the primary illumination source 534 , but separate optics may be utilized to accomplish the desired decorative illumination. For example, light-guiding optics 533 may include an optical light guide or a solid plastic pipe that directs light along its length, creating a linear “stripe” of light down the outside of the device.
[0040] A heat sink 540 may be thermally connected to the thermal path of the illumination device and thus regulate the temperature of the primary illumination source 534 ; the heat sink 540 may be co-linear with the light-guiding optics 533 . Characteristics of the decorative illumination arising from light emitter 531 , such as the intensity, color, frequency, and/or pattern of the light, may be responsive to a remote control that may be either optical (e.g., infrared), wireless (e.g., radio-frequency), or wired (Ethernet, RS-232, etc.).
[0041] As described above, a backward-facing LED sharing a PCB with a primary illumination source may be used for decorative illumination. Furthermore, a separate light emitter, e.g., with dedicated control and/or power circuitry, in the housing may provide decorative illumination. In both cases, decorative illumination is formed actively from a secondary light emitter providing its own light.
[0042] In another embodiment of the present invention, decorative illumination is created passively via utilization of a portion of the light from the primary illumination source. Reflecting optics may be used to direct light from light sources such as LEDs for direct illumination. Such reflecting optics may be aluminized reflectors that may have a parabolic shape to enhance the directionality of the forward light. The optics may also include TIR optics, which utilize the refractive index difference between two different media to yield a reflective internal surface. TIR optics are often very high efficiency (85-90%) compared to ordinary metal-coated reflectors. The design of both types of reflectors is generally intended to maximize optical efficiency with the goal of providing the highest degree of illumination.
[0043] To provide illumination for decorative or other purposes not involving direct illumination, embodiments of the present invention use TIR and other reflecting optics to divert a portion of the light from its otherwise intended path by modifying the optical design of the TIR and other reflecting optics. A portion of light may be “siphoned off” in a controlled way and by means of reflection and refraction be redirected to create the decorative or other non-direct-illumination function. The redirected light may then be used to achieve the desired shape and color for decorative purposes.
[0044] FIG. 5C illustrates another embodiment of the present invention in which a drive circuit 551 converts the mains voltage into a constant current for a primary illumination source 552 (e.g., one or more LEDs). An optic 553 (which may include or consist essentially of, e.g., a TIR lens) may be used to direct light generated by the primary illumination source 552 . A first portion of light generated by the primary illumination source 552 is guided for direct illumination, and a second portion of light is guided for decorative illumination. The first portion of the light is usually larger (i.e., more intense) than the second portion of the light. The first portion of the light generated by the primary illumination source 552 may be directed by the optic 553 and exit a substantially transparent cover 554 attached to the housing (envelope) 555 to provide direct illumination. The housing 555 may include a shade (which may be substantially translucent) and one or more openings 556 in an optical component 557 (e.g., an optical waveguide that may be completely or partially transparent) through which light may exit as decorative illumination. Other approaches such as diffusion and filtering of the light by the optical component 557 may be employed to further condition the light to meet specific decorative or secondary illumination purposes.
[0045] FIG. 5D illustrates another embodiment of the invention operating via similar principles. One or more light channels 581 may connect a housing 582 to an optical component 583 and be utilized to produce decorative illumination therethrough. The light channels 581 may be, e.g., substantially empty passages through the housing, or they may be partially or substantially filled with an optical waveguide material. A portion of the light generated by a primary illumination source 584 (e.g., one or more LEDs) may be directed through the light channels 581 and exit the housing 582 through complementary openings 585 on the shade of the housing 582 .
[0046] It may be appreciated from these descriptions that the LEDs used in these embodiments, though small, occupy considerable space that limits the overall light output of the product. This is due, at least in part, to the need to provide electrical connections to each of the semiconductor light-emitting chips that are housed in large packages that provide both electrical connections and a facility for removing heat and enabling passage of useful light. The packages also often contain a lens or mirror for shaping and directing this light. While these packages allow some freedom of use, they also limit the density and eliminate the ability to integrate the functions of heat dissipation, light direction and electrical connection. Many of these functions may be accommodated within a printed circuit board of appropriate design for a group of devices at the same time and within the circuit as it is formed.
[0047] One way of improving the light density of the overall product is to incorporate the light-emitting dies onto a suitable patterned circuit board that contains the external circuitry needed to power and connect the LED devices without the use of a package. FIG. 6 illustrates such an arrangement. This embodiment includes or consists essentially of a printed circuit board having at least a middle portion 601 that may be the usual fiberglass core or one that contains metals, ceramics or other materials to enhance thermal conductivity, a top metal clad layer 603 , and a bottom cladding layer 602 . It should be well understood that these top and bottom layers can easily be patterned by such processes as etching. A light-emitting assembly may be attached to the patterned surface of cladding 603 by cementing it with a thermally and electrically conducting compound, by welding it, or using any other suitable attachment technique. The cladding 603 then may act as a thermal or electrical conducting pathway, or both. The light-emitting assembly may include a metal base 604 to which is bonded a semiconductor light-emitting chip 605 . This light-emitting chip 605 typically contains a p-n junction that emits light and conducting top and bottom surface layers for electrical and thermal contact. A conducting wire or tab connects the top conducting member of the junction to the opposite conducting pad on the next assembly, thus building up a circuit that is in series. Using a different connection scheme, but the same general approach, a parallel connection may be assembled. By doing this, a relatively dense build-up of light-emitting chips may be assembled using the thermal and electrical transfer characteristics of the printed circuit board. Furthermore, heat sinking, cooling or other components may be attached to the board, improving performance, for example on the back side 602 of the printed circuit board. Although not shown, it should be understood that this connection method may be extended in the two dimensions of the plane of the board.
[0048] Such chips as illustrated in FIG. 6 will generally emit light in all directions. Such a distribution of light may not be desired for many lighting applications. Therefore, a matching array of lenses that is positioned over the light-emitting chips may be utilized. This separation of the top lens array from the LEDs allows the lens array to be positioned independently, so that the light directed by the lens may be moved and/or focused by moving the lens array in three dimensions. The movement may be controlled via, for example, stepper motors or piezoelectric-activated motion controllers whose support electronics are also contained on the printed circuit board. The array of lenses may be molded from a transparent clear or colored material with a variety of spherical or hemi-spherical shapes.
[0049] FIG. 7 illustrates such an arrangement. A PC board 701 containing patterned metal traces 703 has located on its surface light-emitting portions featuring semiconductor light-emitting devices 705 that are mounted on bases 704 . These areas are bonded together with electrically conducting wires or strips to form a series/parallel circuit. Positioned over the top of these light-emitting regions is a lens array 710 into which has been formed (by a method such molding) a matching series of optical elements. Three such elements of two different shapes labeled 711 and 712 are shown. This lens array 710 is spaced apart from the semiconductor array and mounted to facilitate external manipulation in one or more of three dimensions as shown by the opposing pairs of arrows. Hence, by moving the lens array 710 , the light emitted from the matching LED array may be directed and focused as required, in essence steering the light beam. This may be controlled by onboard electronics, and via remote control or such other means as required such as proximity sensors, timers and the like.
[0050] These lighting products generally require a source of AC or DC current. Although LEDs utilize direct current, it is possible to use the LEDs to rectify AC power provided the number of LEDs is chosen to match the AC voltage. It is well understood how to transform AC power to DC. The use of DC power as supplied by batteries, however, may present some problems because as the battery voltage declines under load, the current drawn by the LEDs rapidly declines, owing to the extremely non-linear current-voltage characteristics of the diodes. Since the light output of a LED is typically directly proportional to current (at least in some regimes), this means the light output rapidly declines. On the other hand, if battery voltage exceeds a predetermined level, heating of the semiconductor junction of the LED is excessive and may destroy the device. Moreover, excess heat in the LED junction may cause a condition called thermal runaway, in which the heat raises the current drawn at a given voltage, leading to further heating, which in turn leads to greater current draw and quickly destroys the device. This may be a particular problem with high-power LEDs and requires careful thermal management.
[0051] In order to help avoid this problem it may be useful to fix the current through the LEDs rather than the voltage. Using a battery as the source of current, however, presents a problem because of the differing voltage and current behavior of the battery power source and the LED load. Therefore, a circuit may be utilized to regulate and fix the current independent of the voltage supplied by the battery. In the case where the battery voltage is less than the load voltage required by the series and/or parallel LED circuit, a boost circuit as shown in FIGS. 8( a ) and 8 ( b ) may be employed. In these circuits an integrated circuit device, IC 1 801 , is used to control the charging and discharging of an inductor L 1 803 . This integrated circuit may be any of several that are available such as the Texas Instruments TPS61040. After a charging cycle, the IC switches the circuit so that the inductor L 1 803 is permitted to discharge through the load, which in this case is the light-emitting diodes 805 . The current is controlled via a feedback resistor R 1 806 . The value of the resistor is chosen to fix the maximum current that is permitted to flow through the load, which in this case, is one or more LEDs (LED 1 , LED 2 ) indicated at 805 . This manner of control occurs because the voltage drop across R 1 806 is compared to an internally generated reference voltage at pin FB of IC 1 801 . When the two voltages are equal the current is considered fixed and will be held to that predetermined value. A diode D 3 802 is used to ensure protection of the IC 1 801 in case the battery source (not shown) is connected backwards. The diode 804 allows current flow through the LEDs 805 in only the forward, or light-emitting direction. In embodiments of this invention, such a circuit may be enclosed within the envelope of the bulb.
[0052] The circuit shown in FIG. 8( b ) differs from that of FIG. 8( a ) in that the former contains an easy and inexpensive means of protecting the LEDs from excessive current flow and the runaway that results from high temperatures. In this circuit a resistor with a positive resistance rate of change with temperature, R 2 807 is placed in series with a fixed resistor. Resistor R 2 is physically located on the circuit board so as to be in the thermal pathway of heat emanating from the LEDs 805 . Therefore, when the temperature of the LEDs 805 increases, the resistance of R 2 807 also increases, and its resistance is added to that of R 1 806 . Since the voltage drop across these combined resistances appears on the feedback pin FB of IC 1 801 , the increased voltage is interpreted as a request for decreased current. Hence, the natural tendency of the LEDs 805 to draw more current, which would ordinarily lead to the failure of the part, is averted by introducing a self-limiting control function.
[0053] This circuit has the advantage of being very efficient and compact and having built into it a temperature regulation that allows the resulting system to automatically adapt to the thermal environment in which it is placed. Because of these attributes, it may, for example be put into a miniature lamp base of the kind used for flashlights (e.g., a PR-type flange base).
[0054] However, one possible limitation of the circuit is that it may only boost voltage from a lower value to a higher value required by the LED load. Therefore, in situations where only one LED is required, but a higher input voltage is all that is available, the excess voltage will generally appear across the LED even if one of the circuits in FIG. 8 are used. This may cause an excessive current to be drawn, leading to premature failure of the LED and/or premature draining of the battery. To solve this problem, embodiments of the invention feature a circuit that is preferably still compact enough to fit into a bulb or bulb base, and that is capable of either raising or lowering the output voltage above or below the voltage of the incoming battery or other DC supply in order to maintain the desired current through the LED load. The circuit will either boost the voltage if the input voltage is lower than required by the LED or reduce the voltage if it is higher than that required to sustain the necessary constant current through the LED. It is understood that references to an LED connote one or more LEDs in a series, parallel or series/parallel circuit. Furthermore, because of the deleterious effects of temperature, this circuit typically has the ability to regulate the current through the LED depending on the ambient temperature. The ambient temperature may be determined by the environment as well as heat dissipated by the circuit and the LED.
[0055] Such a circuit is depicted in FIG. 9 . This circuit utilizes a so-called Cuk converter that is ordinarily used as an inverting-switching voltage regulator. Such a device inverts the polarity of the source voltage and regulates the output voltage depending on the values of a resistor bridge. In the illustrated embodiment, the inverter circuit has been altered so that it acts to boost the voltage output or buck the voltage input in order to maintain a constant current through the load represented by one or more LEDs 905 . The circuit incorporates an integrated circuit IC 1 901 such as the National Semiconductor LM2611 Cuk Converter or equivalent. In this circuit, the internal transistor of IC 1 is closed during the first cycle charging the inductor L 1 902 from the battery source indicated as Vbat. At the same time the capacitor C 2 904 charges inductor L 2 903 , while the output current to the LEDs 905 is supplied by inductor L 2 903 . In the next cycle the IC 1 901 changes state to permit the inductor L 1 902 to charge capacitor C 2 904 and L 2 903 to discharge through the LEDs 905 . The control of the charging power and current through the load is performed by the resistor network including or consisting essentially of R 2 906 a and R 3 907 a . The overall value of these resistors together with the current passing through the LEDs 905 from ground, sets a voltage that appears on the feedback pin (FB) of IC 1 901 . Resistor 907 a has a positive temperature coefficient so that its resistance increases with temperature.
[0056] The current may also be altered to accommodate thermal effects such as heat dissipation by the LEDs, heat produced by the IC 1 or other circuit components and/or the ambient environmental conditions. This is effected by a temperature-dependent resistor R 3 . In FIG. 9( a ), resistor R 3 907 a has a positive temperature coefficient in which the resistance increases with temperature. The additive effect of the series circuit with R 2 906 a means that as temperature rises, the overall resistance of the combination does also, leading to an increase in voltage drop. This in turn causes IC 1 to decrease the output current to the LEDs 905 . In FIG. 9( b ) the resistor network includes resistors in parallel and series. In this instance, resistors R 2 and R 4 906 b , 908 are fixed and resistor R 3 907 b is temperature-dependent with a positive temperature coefficient. The use of a parallel arrangement allows a greater freedom of choice of temperature dependence than a simple series arrangement.
[0057] The terms and expressions employed herein are used as terms and expressions of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof. In addition, 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. Accordingly, the described embodiments are to be considered in all respects as only illustrative and not restrictive. | In various embodiments, an illumination device includes a housing, a power connector for connecting the illumination device to a power socket and receiving input power, a light emitter for direct illumination disposed within the housing, a circuit for regulating the input power and providing the regulated power to the light emitter, and a decorative illumination element for providing decorative illumination. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
Automobile drivers and operators of other dangerous equipment occasionally continue operation past the time when they should stop--when they are sleepy. This device is an alarm system to emit a wakening signal should the operator's head tilt. It is intended to improve the chances of equipment operators, and nearby persons, surviving an episode of sleep; thus is considered safety equipment of a specialized kind.
2. Description of Prior Art
A variety of devices for the purpose of awakening vehicle drivers has been proposed. The need has increased in recent years because long stretches of boring freeway have become more common, as has the use of trucks on long hauls. The use of tilting of the head to actuate the wakening alarm is customary, because the need to make the device easily attached and adjusted has been recognized in the art.
Except for Philians U.S. Pat. No. 3,054,868 which uses a chin plate switch attached to the clothing, the present art uses devices attached to a hat, to eyeglass bows, or more commonly to the ear. My use of the teeth to grip the device overcomes two problems which may have prevented widespread use of this type of device. First, the present invention is obviously easier and quicker to mount, which is an advantage in a dark car, while watching the road with the eyes and steering the car with one hand. Second, in using direct coupling to the bone structure it becomes possible to lower the necessary level of audible sounds, rendering the device less disturbing to other occupants of the vehicle. This is possible because the wearer receives some of the sensation of sound from vibration of the mouthpiece transmitted through the bone structure to his ear.
Most of the prior art relies on forward tilt of the head in one plane to close a normally-open mercury switch. Morrison U.S. Pat. No. 2,713,159 and Greene U.S. Pat. No. 3,076,186 include switches which will close if tilted in any plane, but no showing of operability for these switches was made. The present invention responds to tilt in any direction, and also reduces the cost of the switch by making it of fewer parts. The switch includes specific features developed by test to improve operation--specifically to reduce hysteresis.
In addition to making a head-tilt alarm easy to install, one should recognize the fact that the use of it will probably be very irregular, interrupted by months or years when it is simply kept inert, handy to the operator's seat. Thus operators are likely to forget how to activate and how to adjust the devices common in the prior art which have on-off switches or movable protrusions for adjusting the tilt angle setting at which the device actuates. The construction of my mercury switch has the advantage that merely turning the device upside down (inverting it) allows it to be stored for long periods with no drain on the battery. As the user erects it, the buzzer functions to confirm the battery is working, then stops when the silent zone is reached. The absence of a need to remember (or to re-learn by trial and error) how to use the device is an advantage over much of the prior art. The real object of this invention is to help save the lives of people who should not be driving, and minimizing the effect of their inebriation, confusion, or weariness could make an important contribution to that end.
SUMMARY OF THE INVENTION
The invention has a mouthpiece which is held between the upper and lower teeth as is a pipe. A portion of the mouthpiece extends outward between the lips. To this portion is attached a source of electric energy such as a battery, connected in series with a tilt switch and an electromagnetic buzzer. Such buzzers make audible sound by mechanical means, generating both a noise and a vibration. Both are transmitted to the ear and are perceived as a sound.
The tilt switch is typically formed from two dished discs of thin metal, rim to rim, separated by an insulating washer. When the switch is upright, with the rims horizontal, a pool of mercury rests in the center of the lower disc which is only slightly dished. The upper disc is deeply dished in the preferred embodiment, enough to clear the top of the pool of mercury by a substantial distance. When the switch oriented as described is tilted sufficiently from the level or horizontal position, the mercury pool approaches the rims of the discs and establishes electrical contact from the lower disc through the mercury to the upper disc, closing the switch. When the tilt switch is inverted, the mercury pool rests in the (now lower) deeply dished disc and is isolated from the rim except at very large tilt angles. Thus it may be stored ready for use without depletingthe battery. The preferred embodiment thus omits the on-off switch as a simplification for the user. It also eliminates the adjustment of tilt angle so as to make it unnecessary for the user to be familiar with the device; the mouthpiece may have a contoured portion which allows the user to adjust the set angle a few degrees by "pointing" the device more toward the front or more toward the side of the head, and by gripping it close to or farther from the end of the mouthpiece.
The principal novelty of this invention is that it is gripped in the teeth. Two distinct advantages derive from this. First, it is extremely easy to install on or to remove from the head, which may encourage more people to own it and to use it. Second, the force transmitted to the air to make sound is reacted directly by the head bones without intervening tissue, so the noise perceived through the bone structure is close to the maximum possible.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the alarm as it would be used, cutaway to show the main elements.
FIG. 2 is a cross sectional side view of the preferred embodiment, showing the preferred version of the tilt switch.
FIG. 3 is a partial view taken looking downward on the preferred embodiment with the buzzer removed. Some sections are cut away.
FIG. 4 is a cutaway perspective view of a second version of the tilt switch.
FIG. 5 is a cross sectional view of a third version of the tilt switch.
FIG. 6 is a cross sectional view of a fourth version of the tilt switch.
FIG. 7 is a top view of the contoured portion of the mouthpiece.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1 a partial cutaway view of the invention is shown in the mouth of a user. The invention may be retrieved from its storage place, inverted and placed in between the teeth quickly--a positive factor encouraging its use. Mouthpiece (1) is clamped between the upper and lower teeth, extends outward forward of the lips, and incorporates provision for holding all of the other elements except possibly the d.c. power source and the leads thereto. The angle at which the alarm is held is essentially level, although contoured portion (10) of mouthpiece (1) may be used to provide a few degrees adjustment. This is better illustrated in FIG. 7. When upright, the alarm sounds until it is within a few degrees of level so the user has no difficulty in finding the silent zone. FIG. 1 also shows the preferred placement of (2) tilt switch, (3) electromagnetic buzzer, (14) battery, and one connection (4) to the battery. All are placed relatively near the teeth so as to reduce the moment on the teeth, and the upper face of buzzer (3) provides a stable base when the invention is stored inverted.
FIG. 2 shows mouthpiece (1) with contoured portion (10) in a side elevation of the preferred embodiment. Battery (14) is held between connections (4); in this embodiment one connection (4) is the lower surface of tilt switch (2). The other connection (4) carries voltage through lead (15) to buzzer (3). The other lead or leadwire from the buzzer is connected to spring (17) which makes electrical contact with the upper surface of tilt switch (2).
In the embodiment shown in FIG. 2 tilt switch (2) is partially cut away to show first terminal (5), mercury pool (13), insulating gasket (8), and second terminal (6). The word terminal in this explanation is considered to include all matter to which current coming to or leaving the switch can flow with little or no resistance, except the pool of mercury which is separately identified. Thus electric potential is equal throughout a terminal, thus two metal parts in electric contact are one terminal, and a terminal may be a metallic or otherwise conductive coating independent of its supporting substrate. Also the expression transversely fixed means that the parts referred to may not shift relative to each other laterally, the features of elements remain in the position described relative to each other during tilt or inversion. "Abutting", "wall slope" and "Circumferential direction" have the obvious meanings.
FIG. 3 is a top view of the alarm parts beneath the buzzer (3). The central part of spring (17) is cut away exposing switch (2) which is also partially cut away to show pool of mercury (13) as it would appear when the switch was tilted and mercury (13) was in contact with second terminal (6) as well as first terminal (5) on which it rests. Two leads (15) from the buzzer are shown, one attached to spring (17) and one to connection (4). As shown gasket (8) which separates terminals (5) and (6) is larger in diameter than either thus preventing them from touching connection (4), but obviously other means to isolate connection (4) are possible.
FIG. 4 shows another version of tilt switch (2) in perspective, cut away to show the detail of first terminal (5), namely the concave (or depressed) portion (or region) (9) and rim portion (also called rim or first terminal rim) (11). This is the preferred embodiment; function of the switch would not be changed if the first terminal rim (11) were a separate part, or a non-conductor, or at a different elevation than that shown. A cover dish (16) is shown in FIG. 4. It serves to seal in the mercury and to support it when the switch is inverted, in the event the second terminal (6) takes the form of a ring or another shape with an internal opening or aperture in it which surrounds the pool of mercury at a point below the top of the pool. The aperture need not have cylindrical walls; my tests have shown that sharp ridges running in any direction help cause the mercury to break away at tilt angles close to those at which it makes contact thus reducing hysteresis.
Irregularities in the internal surface of second terminal (6) are illustrated in the cross section view of a third version of tilt switch (2), FIG. 5. This view also shows concave portions (9) and (12) respectively on each terminal (5) and (6), as well as first terminal rim (11). The pool of mercury is not shown, but the ridges visible on terminal (6) are at a level approximately mid-height of the mercury pool for best results.
FIG. 6 shows a fourth version of tilt switch (2) which would be suitable if the alarm was to be invertable not to store it but to provide for more than one tilt angle setting in a single alarm. A third terminal (7) is illustrated, and the second terminal (6) is illustrated as having a tab for making connections to it at one side of the saw-cut cross section. The same remarks as made earlier about the rim (11) and concave portion (9) of first terminal (5) apply to third terminal (7).
FIG. 7 shows the preferred embodiment of the part of mouthpiece (1) containing contoured region (10). Many shapes are possible, but shown is two crowned ridges on the upper surface near the edges of the mouthpiece, the peak of the rightmost crowned region being closer to the end of the mouthpiece that the peak of the left ridge. Thus the wearer's teeth, which contact both upper and lower surfaces at an angle to the length of the mouthpiece will bear fairly securely on the broad lower surface and at two discrete areas on the upper surface (on the crowned ridges). By selecting the different amounts of penetration inward of the teeth or by moving the mouthpiece more to the front or more to the side of the head, the wearer can control the angle of the mouthpiece relative to horizontal or level, and so exert some control on the angle at which the tilt switch closes, sounding the alarm.
This invention having been described in its preferred embodiment, it is clear that it is susceptible to numerous modifications and embodiments within the ability of those skilled in the art without the exercise of the inventive faculty. Accordingly, the scope of this invention is defined by the scope of the following claims. | An alarm intended to alert the operator of dangerous equipment, such as the driver of an automobile, when his head tilts as from drowsiness or sleep. Intended to be of utmost convenience so as to encourage its use, the device is gripped between the teeth by a mouthpiece. Vibration concomitant with making the sound it emits is partially transmitted through the bone structure of the head, reducing the needed noise level and so the disturbance of nearby persons. The preferred embodiment is sensitive to tilt in any direction, and may be stored inverted in which position it tolerates large tip angles without sounding. | 8 |
THE FIELD OF THE INVENTION
The present invention relates to implantable medical devices (IMDs). Specifically, the invention pertains to a remote bi-directional communications between the IMDs and a drug dispenser. More specifically the invention pertains to a closed loop system in which the IMDs monitor and determine the presence of a specific drug dose in the patient's body to send instructions to the drug dispenser or an interface medical unit (IMU) to implement a drug management scheme based on the monitored data. More specifically, the invention provides a dynamic drug management system in which the drug dose is chronically monitored by the IMDs to enhance drug effectiveness and as well monitor patient compliance with recommended drug administration regimen. The invention preferably utilizes a robust communication system integrated with a remote expert data center in a web-enabled environment to transmit the IMDs' data to a physician for evaluation and review thereby enhancing the delivery of therapy and clinical care remotely.
BACKGROUND OF THE INVENTION
A technology-based health care system that fully integrates the technical and social aspects of patient care and therapy should be able to flawlessly connect the client with care providers irrespective of separation distance or location of the participants. While clinicians will continue to treat patients in accordance with accepted modern medical practice, developments in communications technology are making it ever more possible to provide a seamless system of remote patient diagnostics, care and medical services in a time and place independent manner.
Prior art methods of clinical services are generally limited to in-hospital operations. For example, if a physician needs to review the performance parameters of an implantable device in a patient, it is likely that the patient has to go to the clinic. Further, if the medical conditions of a patient with an implantable device warrant a continuous monitoring or adjustment of the device, the patient would have to stay in a hospital indefinitely. Further, if the patient with the IMDs is taking a drug, it is often clinically prudent to monitor the dose and its impact on the patient and, as well, on the IMDs. Such a continued treatment plan poses both economic and social problems. Under the exemplary scenario, as the segment of the population with implanted medical devices increases many more hospitals/clinics including service personnel will be needed to provide in-hospital service for the patients, thus escalating the cost of healthcare. Additionally the patients will be unduly restricted and inconvenienced by the need to either stay in the hospital or make very frequent visits to a clinic.
Yet another condition of the prior art practice requires that a patient visit a clinic center for occasional retrieval of data from the implanted device to assess the operations of the device and gather patient history for both clinical and research purposes. Such data is acquired by having the patient in a hospital/clinic to down load the stored data from the implantable medical device. Depending on the frequency of data collection this procedure may pose serious difficulty and inconvenience for patients who live in rural areas or have limited mobility. Similarly, in the event a need arises to upgrade the software of an implantable medical device, the patient will be required to come into the clinic or hospital to have the upgrade installed. Further, in medical practice it is an industry-wide standard to keep an accurate record of past and contemporaneous procedures relating to an IMD uplink with, for example, a programmer. It is required that the report contain the identification of all the medical devices involved in any interactive procedure. Specifically, all peripheral and major devices that are used in down linking to the IMD need to be reported. Currently, such procedures are manually reported and require an operator or a medical person to diligently enter data during each procedure. One of the limitations of the problems with the reporting procedures is the fact that it is error prone and requires rechecking of the data to verify accuracy.
A further limitation of the prior art relates to the management of multiple medical devices in a single patient. Advances in modern patient therapy and treatment have made it possible to implant a number of devices in a patient. For example, IMDs such as a defibrillator or a pacer, a neural implant, a drug pump, a separate physiologic monitor and various other IMDs may be implanted in a single patient. To successfully manage the operations and assess the performance of each device in a patient with multi-implants requires a continuous update and monitoring of the devices. As is often the case, patients with multi-implanted medical devices may take a variety of medications. It is therefore necessary to monitor drug intake and its effect on the oprerational and functional parameters of the IMDs. More importantly, chronic monitoring of drug intake and its effect on the physiological and clinical conditions of the patient enables a proactive intervention to change the course of an otherwise serious medical condition. Thus, there is a need to monitor drug delivery and effectiveness via IMDs.
Accordingly it is vital to have a drug dispenser unit that would establish a communication system with IMDs. The unique position of IMDs enables a real-time assessment of physiological conditions which may change or indicate a measurable variance due to drug dose and delivery. IMDs could be adapted to provide measurements relating to the physiological impact of drug therapy. Further, IMDs could be adapted to provide a quick evaluation of the effectiveness of a drug to support a clinical decision as to whether a given dose is a prudent course of therapy.
The proliferation of patients with multi-implant medical devices worldwide has made it imperative to provide remote services to the IMDs and timely clinical care to the patient. Frequent use of programmers to communicate with the IMDs and provide various remote services, consistent with co-pending applications titled “Apparatus and Method for Remote Troubleshooting, Maintenance and Upgrade of Implantable Device Systems,” filed on Oct. 26, 1999, Ser. No. 09/426,741; “Tactile Feedback for Indicating Validity of Communication Link with an Implantable Medical Device,” filed Oct. 29, 1999, Ser. No. 09/430,708; “Apparatus and Method for Automated Invoicing of Medical Device Systems,” filed Oct. 29, 1999, Ser. No. 09/430,208; “Apparatus and Method for Remote Self-Identification of Components in Medical Device Systems,” filed Oct. 29, 1999, Ser. No. 09/429,956; “Apparatus and Method to Automate Remote Software Updates of Medical Device Systems,” filed Oct. 29, 1999, Ser. No. /429,960; “Method and Apparatus to Secure Data Transfer From Medical Device Systems,” filed Nov. 2, 1999, Ser. No. 431,881; “Implantable Medical Device Programming Apparatus Having An Auxiliary Component Storage Compartment,” filed Nov. 4, 1999, Ser. No. 433,477; which are all incorporated by reference herein in their entirety, has become an important aspect of patient care. Thus, in light of the referenced disclosures, communication with IMDs enhances the delivery of therapy and clinical care in real time. Specifically, as the number of patients with IMDs increases globally, the need to manage drug delivery and intake remotely becomes an economic imperative. Further, IMDs which are communicable and operable in a web-enabled environment, as contemplated by the cited disclosures hereinabove, provide a unique platform to assess the efficacy of drugs and the compliance of patients with prescribed regimens. Further, it is vital to have a drug dispenser that is adapted to have data communications with the IMDs and other data centers to support the remote patient management system contemplated by the present invention.
The prior art provides various types of remote sensing and communications with an implanted medical device. One such system is, for example, disclosed in Funke, U.S. Pat. No. 4,987,897 issued Jan. 29, 1991. This patent discloses a system that is at least partially implanted into a living body with a minimum of two implanted devices interconnected by a communication transmission channel. The invention further discloses wireless communications between an external medical device/programmer and the implanted devices.
One of the limitations of the system disclosed in the Funke patent includes the lack of communication between the implanted devices, including the programmer, with a remote clinical station. If, for example, any assessment, monitoring or maintenance is required to be performed on the IMD the patient will have to go to the remote clinic station or the programmer device needs to be brought to the patient's location. More significantly, the operational worthiness and integrity of the programmer cannot be evaluated remotely thus making it unreliable over time as it interacts with the IMD. Further, in light of the present invetion, the Funke patent does neither suggest nor disclose the communications system between the IMD and a drug dispenser to monitor and assess in the effectiveness of the dose based on the physiological status of the patient.
Yet another example of drug management based on smart drug dispenser units is disclosed by Martindale et al in U.S. Pat. No. 4,360,125 issued on Nov. 23, 1982. In the disclosure, a medication dispenser in which medication to be dispensed is housed including a member operable to allow medication access. The dispenser provides a medication alert signal at preselected times in accordance with a desired medication regimen. A medication access signal is provided when medication access is obtained. Data representative of the relative timing between a medication alert signal and a medication access signal is written into readable memory whereby that data is available to a physician for evaluation. In the preferred embodiment, the data is representative of the time of occurrence of each medication alert signal and medication access signal. The interval between medication alert signals is selectively alterable.
Further, examples of drug management based on smart drug dispensers are disclosed in U.S. Pat. Nos. 4,768,176; 4,768,177; 5,200,891; 5,642,731; 5,752,235 and 5,954,641 all to Kehr et al. Generally all the patents relate to a drug dispensing system with various alert features to monitor and manage the administration of medication and medical treatment regimens. None of these patents suggest or disclose a communication between the drug dispensing systems and an IMD.
Yet another prior art reference provides a multi-module medication delivery system as disclosed by Fischell in U.S. Pat. No. 4,494,950 issued Jan. 22, 1985. The disclosure relates to a system consisting a multiplicity of separate modules that collectively perform a useful biomedical purpose. The modules communicate with each other without the use of interconnecting wires. All the modules may be installed intracorporeal or mounted extracorporeal to the patient. In the alternate, some modules may be intracorporeal with others being extracorporeal. Signals are sent from one module to the other by electromagnetic waves. Physiologic sensor measurements sent from a first module cause a second module to perform some function in a closed loop manner. One extracorporeal module can provide electrical power to an intracorporeal module to operate a data transfer unit for transferring data to the external module.
The Fischell disclosure provides modular communication and cooperation between various medication delivery systems. However, the disclosure does not provide an external pill dispenser which is in wireless communications with IMDs. Further, the system does neither teach nor disclose an external programmer for telemetrically interacting with the pill dispenser.
Accordingly, it would be advantageous to provide a pill dispenser that communicates with IMDs to implement an effective drug management system. Yet another desirable advantage would be to provide a high speed communications scheme to enable the transmission of high fidelity sound, video and data to advance and implement efficient remote drug management of a clinical/therapy system via a programmer thereby enhancing patient clinical care. As discussed herein below, the present invention provides these and other desirable advantages.
SUMMARY OF THE INVENTION
The present invention generally relates to a communications scheme in which a remote web-based expert data center interacts with a patient having one or more implantable medical devices (IMDs) via an associated external medical device, preferably a programmer, located in close proximity to the IMDs. The IMDs are adapted to communicate with a pill dispenser to monitor and log pill deposition and effectiveness. Some of the most significant advantages of the invention include the use of various communications media between the remote web-based expert data center and the programmer to remotely exchange clinically significant information and ultimately effect real-time drug intake and prescriptive changes as needed.
One of the many aspects of the present invention includes a real-time access of a programmer or a pill dispenser to a remote web-based expert data center, via a communication network, which includes the Internet. The operative structure of the invention includes the remote web-based expert data center, in which an expert system is maintained, having a bi-directional real-time data, sound and video communications with the programmer via a broad range of communication link systems. The programmer is in turn in telemetric communications with the IMDs such that the IMDs may uplink to the programmer or the programmer may down link to the IMDs, as needed.
Yet another feature of the invention includes a communications scheme that provides a highly integrated and efficient method and structure of clinical information management in which various networks such as Community access Television, Local area Network (LAN), a wide area network (WAN) Integrated Services Digital Network (ISDN), the Public Switched telephone Network (PSTN), the Internet, a wireless network, an asynchronous transfer mode (ATM) network, a laser wave network, satellite, mobile and other similar networks are implemented to transfer voice, data and video between the remote data center and a programmer. In the preferred embodiment, wireless communications systems, a modem and laser wave systems are illustrated as examples only and should be viewed without limiting the invention to these types of communications alone. Further, in the interest of simplicity, the applicants refer to the various communications system, in relevant parts, as a communications system. However, it should be noted that the communication systems, in the context of this invention, are interchangeable and may relate to various schemes of cable, fiber optics, microwave, radio, laser and similar communications or any practical combinations thereof.
Some of the distinguishing features of the present invention include the use of a robust web-based expert data center to collect drug therapy information based on data communication between the IMDs, the pill dispenser and the programmer. Specifcally the invention enables remote evaluation of drug performance in a patient. Although the present invention focuses on the remote real-time monitoring and management of drug therapy information, the system could advantageously be used to monitor clinical trials of drugs or collect clinical data relating to drug interaction or physiological impact of various doses on the patient.
Yet one of the other distinguishing features of the invention includes the use a highly flexible and adaptable communications scheme to promote continuous and real-time communications between a remote expert data center, a programmer and a pill dispenser associated with a plurality of IMDs. The IMDs are structured to share information intracorporeally and may interact with the programmer or the pill dispenser as a unit. Specifically, the IMDs either jointly or severally can be interrogated to implement or extract clinical information as required. In other words, all of the IMDs may be accessed via one IMD or, in the alternate, each one of the IMDs may be accessed individually. The information collected in this manner may be transferred to the data center via the programmer or pill dispenser by up linking the IMDs as needed.
The invention provides significant compatibility and scalability to other web-based applications such as telemedicine and emerging web-based technologies such as tele-immersion. For example, the system may be adapted to webtop applications in which a webtop unit may be used to uplink the patient to a remote data center for drug information exchange between the IMDs and the remote expert data center. In these and other web-based similar applications the data collected, in the manner and substance of the present invention, may be used as a preliminary screening to identify the need for further intervention using the advanced web technologies.
More significantly, the invention provides a system and method to remotely monitor drug effectiveness in a patient. Further, the invention enables a chronic evaluation of drugs in a patient on real time basis. The significance of this method includes the fact that the data collected in this manner could be used to influence the course of drug therapy.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be appreciated as the same becomes better understood by reference to the following detailed description of the preferred embodiment of the invention when considered in connection with the accompanying drawings, in which like numbered reference numbers designate like parts throughout the figures thereof, and wherein:
FIG. 1 is a simplified schematic diagram of major uplink and downlink telemetry communications between a remote clinical station, a programmer and a plurality of implantable medical devices (IMDs);
FIG. 2 is a block diagram representing the major components of an IMD;
FIG. 3A is a block diagram presenting the major components of a programmer;
FIG. 3B is a block diagram representing a laser transceiver for high speed transmission of voice, video and other data;
FIGS. 4A, 4 B and 4 C illustrate a perspective view, a side view and a schematic for the drug dispensing unit or interface medical unit, respectively; and
FIG. 5 is a block diagram representing the major data centers and the communication scheme according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a simplified schematic of the major components of the present invention. Specifically, a bi-directional wireless communications system between programmer 20 , pill dispenser 20 ′ and a number of implantable medical devices (IMDS) represented by IMD 10 , IMD 10 ′ and IMD 10 ″ is shown. The IMDs are implanted in patient 12 beneath the skin or muscle. The IMDs are electrically coupled to electrodes 18 , 3 0 , and 3 6 respectively in a manner known in the art. IMD 10 contains a microprocessor for timing, sensing and pacing functions consistent with preset programmed functions. Similarly, IMDs 10 ′ and 10 ″ are microprocessor-based to provide timing and sensing functions to execute the clinical functions for which they are employed. For example, IMD 10 ′ could provide neural stimulation to the brain via electrode 30 and IMD 10 ″ may function as a drug delivery system that is controlled by electrode 36 . The various functions of the IMDs are coordinated using wireless telemetry. Wireless links 42 , 44 and 46 jointly and severally couple IMDs 10 , 10 ′ and 10 ″ such that programmer 20 may transmit commands or data to any or all the of IMDs via one of telemetry antennas 28 , 32 and 38 . This structure provides a highly flexible and economical wireless communications system between the IMDS. Further, the structure provides a redundant communications system, which enables access to any one of a multiplicity of IMDs in the event of a malfunction of one or two of antennas 28 , 32 and 38 .
Programming commands or data are transmitted from programmer 20 to IMDs 10 , 10 ′ and 10 ″ via external RF telemetry antenna 24 . Telemetry antenna 24 may be an RF head or equivalent. Antenna 24 may be located on programmer 20 externally on the case or housing. Telemetry antenna 24 is generally telescoping and may be adjustable on the case of programmer 20 . Both programmer 20 and pill dispenser 20 ′ may be placed a few feet away from patient 12 and would still be within range to wirelessly communicate with telemetry antennas 28 , 32 and 38 .
The uplink to remote web-based expert data center 62 , hereinafter referred to as, interchangeably, “data center 62 ”, “expert data center 62 ” or “web-based data center 62 ” without limitations, is accomplished through programmer 20 or webtop unit 20 ′. Accordingly programmer 20 and webtop unit 20 ′ function as an interface between IMDs 10 , 10 ′ and 10 ″ and data center 62 . One of the many distinguishing elements of the present invention includes the use of various scalable, reliable and high-speed wireless communication systems to bi-directionally transmit high fidelity digital/analog data between programmer 20 and data center 62 .
There are a variety of wireless mediums through which data communications could be established between programmer 20 or pill dispenser 20 ′ and data center 62 . The communications link between Programmer 20 or pill dispenser 20 ′ and data center 62 could be modem 60 , which is connected to programmer 20 on one side at line 63 and data center 62 at line 64 on the other side. In this case, data is transferred from data center 62 to programmer 20 via modem 60 . Alternate data transmission systems include, without limitations, stationary microwave and/or RF antennas 48 being wirelessly connected to programmer 20 via tunable frequency wave delineated by line 50 . Antenna 48 is in communications with data center 62 via wireless link 65 . Similarly, pill dispenser 20 ′, mobile vehicle 52 and satellite 56 are in communications with data center 62 via wireless link 65 . Further, mobile system 52 and satellite 56 are in wireless communications with programmer 20 or pill dispenser 20 ′ via tunable frequency waves 54 and 58 , respectively.
In the preferred embodiment a Telnet system is used to wirelessly access data center 62 . Telnet emulates a client/server model and requires that the client run a dedicated software to access data center 62 . The Telnet scheme envisioned for use with the present invention includes various operating systems including UNIX, Macintosh, and all versions of Windows. A further preferred embodiment includes a client/server paradigm that mutually connects various components of the system in the present invention by means of the network protocol. Client applications and a server application may be installed and differently distributed within the disclosed systems. Data Center 62 runs the server application. Further, TCP/IP protocol may be used in various operating systems, consistent with well-known procedures in the art, while new protocols are being developed.
Functionally, an operator at programmer 20 or an operator at data center 62 would initiate remote contact. Programmer 20 is down linkable to IMDs via link antennas 28 , 32 and 38 to enable data reception and transmission. For example, an operator or a clinician at data center 62 may downlink to programmer 20 to perform a routine or a scheduled evaluation of programmer 20 . In this case the wireless communication is made via wireless link 65 . If a downlink is required from programmer 20 to IMD 10 for example, the downlink is effected using telemetry antenna 22 . In the alternate, if an uplink is initiated from patient 12 to programmer 20 the uplink is executed via wireless link 26 . As discussed herein below, each antenna from the IMDs can be used to uplink all or one of the IMDs to programmer 20 . For example, IMD 10 ″ which relates to neural implant 30 can be implemented to up-link, via wireless antenna 34 or wireless antenna 34 ′, any one, two or more IMDs to programmer 20 . Preferably bluetooth chips, adopted to function within the body to outside the body and also adopted to provide low current drain, are embedded in order to provide wireless and seamless connections 42 , 44 and 46 between IMDs 10 , 10 ′ and 10 ″. The communication scheme is designed to be broadband compatible and capable of simultaneously supporting multiple information sets and architecture, transmitting at relatively high speed, to provide data, sound and video services on demand.
FIG. 2 illustrates typical components of an IMD, such as those contemplated by the present invention. Specifically, major operative structures common to all IMDs 10 , 10 ′ and 10 ″ are represented in a generic format. In the interest of brevity, IMD 10 relative to FIG. 2 refers to all the other IMDs. Accordingly, IMD 10 is implanted in patient 12 beneath the patient's skin or muscle and is electrically coupled to heart 16 of patient 12 through pace/sense electrodes and lead conductor(s) of at least one cardiac pacing lead 18 in a manner known in the art. IMD 10 contains timing control 72 including operating system that may employ microprocessor 74 or a digital state machine for timing, sensing and pacing functions in accordance with a programmed operating mode. IMD 10 also contains sense amplifiers for detecting cardiac signals, patient activity sensors or other physiologic sensors for sensing the need for cardiac output, and pulse generating output circuits for delivering pacing pulses to at least one heart chamber of heart 16 under control of the operating system in a manner well known in the prior art. The operating system includes memory registers or RAM/ROM 76 for storing a variety of programmed-in operating mode and parameter values that are used by the operating system. The memory registers or RAM/ROM 76 may also be used for storing data compiled from sensed cardiac activity and/or relating to device operating history or sensed physiologic parameters for telemetry out on receipt of a retrieval or interrogation instruction. All of these functions and operations are well known in the art, and many are generally employed to store operating commands and data for controlling device operation and for later retrieval to diagnose device function or patient condition.
Programming commands or data are transmitted between IMD 10 RF telemetry antenna 28 , for example, and an external RF telemetry antenna 24 associated with programmer 20 . In this case, it is not necessary that the external RF telemetry antenna 24 be contained in a programmer RF head so that it can be located close to the patient's skin overlying IMD 10 . Instead, the external RF telemetry antenna 24 can be located on the case of programmer 20 . It should be noted that programmer 20 can be located some distance away from patient 12 and is locally placed proximate to the IMDs such that the communication between IMDs 10 , 10 ′ and 10 ″ and programmer 20 is telemetric. For example, programmer 20 and external RF telemetry antenna 24 may be on a stand a few meters or so away from patient 12 . Moreover, patient 12 may be active and could be exercising on a treadmill or the like during an uplink telemetry interrogation of real-time ECG or other physiologic parameters. Programmer 20 may also be designed to universally program existing IMDs that employ RF telemetry antennas of the prior art and therefore also have a conventional programmer RF head and associated software for selective use therewith.
In an uplink communication between IMD 10 and programmer 20 , for example, telemetry transmission 22 is activated to operate as a transmitter and external RF telemetry antenna 24 operates as a telemetry receiver. In this manner data and information may be transmitted from IMD 10 to programmer 20 . In the alternate, IMD 10 RF telemetry antenna 26 operates as a telemetry receiver antenna to downlink data and information from programmer 20 . Both RF telemetry antennas 22 and 26 are coupled to a transceiver comprising a transmitter and a receiver.
FIG. 3A is a simplified circuit block diagram of major functional components of programmer 20 . The external RF telemetry antenna 24 on programmer 20 is coupled to a telemetry transceiver 86 and antenna driver circuit board including a telemetry transmitter and telemetry receiver 34 . The telemetry transmitter and telemetry receiver are coupled to control circuitry and registers operated under the control of microcomputer 80 . Similarly, within IMD 10 , for example, the RF telemetry antenna 26 is coupled to a telemetry transceiver comprising a telemetry transmitter and telemetry receiver. The telemetry transmitter and telemetry receiver in IMD 10 are coupled to control circuitry and registers operated under the control of microcomputer 74 .
Further referring to FIG. 3A, programmer 20 is a personal computer type, microprocessor-based device incorporating a central processing unit, which may be, for example, an Intel Pentium microprocessor or the like. A system bus interconnects CPU 80 with a hard disk drive, storing operational programs and data, and with a graphics circuit and an interface controller module. A floppy disk drive or a CD ROM drive is also coupled to the bus and is accessible via a disk insertion slot within the housing of programmer 20 . Programmer 20 further comprises an interface module, which includes a digital circuit, a non-isolated analog circuit, and an isolated analog circuit. The digital circuit enables the interface module to communicate with interface controller module. Operation of the programmer in accordance with the present invention is controlled by microprocessor 80 .
In order for the physician or other caregiver or operator to communicate with the programmer 20 , a keyboard or input 82 coupled to CPU 80 is optionally provided. However the primary communications mode may be through graphics display screen of the well-known “touch sensitive” type controlled by a graphics circuit. A user of programmer 20 may interact therewith through the use of a stylus, also coupled to a graphics circuit, which is used to point to various locations on screen or display 84 which display menu choices for selection by the user or an alphanumeric keyboard for entering text or numbers and other symbols. Various touch-screen assemblies are known and commercially available. Display 84 and or the keyboard comprise means for entering command signals from the operator to initiate transmissions of downlink or uplink telemetry and to initiate and control telemetry sessions once a telemetry link with data center 62 or an implanted device has been established. Display screen 84 is also used to display patient related data and menu choices and data entry fields used in entering the data in accordance with the present invention as described below. Display screen 84 also displays a variety of screens of telemetered out data or real-time data. Display screen 84 may also display plinked event signals as they are received and thereby serve as a means for enabling the operator to timely review link-history and status.
Programmer 20 further comprises an interface module, which includes digital circuit, non-isolated analog circuit, and isolated analog circuit. The digital circuit enables the interface module to communicate with the interface controller module. As indicated hereinabove, the operation of programmer 20 , in accordance with the present invention, is controlled by microprocessor 80 . Programmer 20 is preferably of the type that is disclosed in U.S. Pat. No. 5,345,362 to Winkler, which is incorporated by reference herein in its entirety.
Screen 84 may also display up-linked event signals when received and thereby serve as a means for enabling the operator of programmer 20 to correlate the receipt of uplink telemetry from an implanted device with the application of a response-provoking action to the patient's body as needed. Programmer 20 is also provided with a strip chart printer or the like coupled to interface controller module so that a hard copy of a patient's ECG, EGM, marker channel of graphics displayed on the display screen can be generated.
As will be appreciated by those of ordinary skill in the art, it is often desirable to provide a means for programmer 20 to adapt its mode of operation depending upon the type or generation of implanted medical device to be programmed and to be compliant with the wireless communications system through which data and information is transmitted between programmer 20 and data center 62 .
FIG. 3B is an illustration of the major components of Wave unit 90 utilizing laser technologies such as for example the WaveStar Optic Air Unit, manufactured by Lucent Technologies or equivalent. This embodiment may be implemented for large data transfer at high speed in applications involving several programmers. The unit includes laser 92 , transceiver 94 and amplifier 96 . A first wave unit 90 is installed at data center 62 and a second unit 90 ′ is located proximate to programmer 20 or pill dispenser 20 ′. Data transmission between remote data center 62 and programmer unit 20 is executed via wave units 90 . Typically, the first wave unit 90 accepts data and splits it into unique wavelength for transmission. The second wave unit 90 ′ recomposes the data back to its original form.
FIGS. 4A, 4 B and 4 C represent various views of pill dispenser unit 20 ′. The structure includes pill containers 100 that protrude upwards from the surface for pill or drug containment. The structure also includes upper metalized layer 102 , superimposed on a plastic cover and lower metalized layer 104 superimposed on a plastic cover. Piezoelectric film 106 is disposed between the upper and the lower metalized layers. Further, microprocessor 108 is embedded between the upper and the lower layers. Telemetric antenna 110 is in electronic communications with microprocessor 108 and extends outward proximate therefrom.
Pill container 100 includes an indicator for the absence or presence of a pill in containers 100 . Pill dispenser unit 20 ′ is in preferably telemetric or equivalent wireless communications with IMDs 10 , 10 ′ and 10 ″. In the alternate, pill dispenser unit 20 ′ is in data communications with programmer 20 .
Referring to FIG. 5, a communication scheme between remote data center 62 , physician station 120 and programmer 20 and/or pill dispenser unit 20 ′. As indicated hereinabove, data center 62 includes high-speed computers and is preferably web enabled to provide remote access. Communication links A, B, C, D, E and F are preferably wireless although any other communication system such as cable, fiber-optics or equivalent could be implemented.
Generally, the present invention provides drug delivery and management primarily based on the chronic communications between pill dispenser unit 20 ′ and IMDs 10 , 10 ′ and 10 ″. Specifically, IMDs 10 , 10 ′ and 10 ″ include a software program which would monitor the number of pills in pill dispenser 20 ′ via link B which is equivalent to telemetry 110 . In the alternate, the number of pills in dispenser 20 ′ may be tracked via link C which establishes the communication between pill dispenser 20 ′ and programmer 20 . Pill dispenser 20 ′ includes means for indicating the pill deposition from the package or container. Further IMDs 10 , 10 ′ and 10 ″ include means for monitoring the deposition of the pills. A prescribed therapy schedule is preferably preprogrammed in the memory of IMDs 10 , 10 ′ and 10 ″. The actual pill deposition in container 100 is known and correlates to one or more of the parameters programmed in IMDs 10 , 10 ′ and 10 ″. Thus, the actual pill removal is assumed to be a precursor of administration of the pill by the patient consistent with the prescribed regimen. The relevant marker designating the time, dosage, and the type of medication is generated within a various diagnostic tables, and trend curves representing different physiologic parameters.
Further, IMDs 10 , 10 ′ and 10 ″ chronically monitor the physiologic parameters of the patient and may alert the patient in cases, for example, when the drug does not influence a trend curve, causes the trends curve to oscillate, patient is not following the prescribed regimen or patient stops taking the medication altogether. Subsequently, IMDs 10 , 10 ′ and 10 ″ could alert the physician or clinician to confer with the patient. This may be done via programmer 20 up-linking to data center 62 . The Physician at station 120 will be able to access the patient data from data center 62 . As shown in FIG. 5, Pill dispenser 20 ′ is in data communication with data center 62 . Thus the status of pill dispenser 20 ′ is registered in either device or patient databases for the clinician to investigate.
Pill dispenser 20 ′ is generally structured with a plurality of metal;lic layers such as 102 and 104 , preferably aluminum and plastic layers. Thus pill dispenser 20 ′ is a capacitor cell. Piezoelectric film 106 is similar to commercially available Kynar or equivalent, sandwithced between the two layers. Accordingly, whenever the patient manipulates pill dispenser 20 ′ to break container 100 and remove a pill, a voltage will be produced within the piezoelectric film. This voltage may be used as a signal to the IMDs indicating the removal of a pill. Specifically, the signal being different from ECG, EMG, EMI or any other body generated signal, is suited to be used as a signal from pill dispenser 20 ′ to IMDs 10 . 10 ′ and 10 ″. IMDs 10 , 10 ′ and 10 ″ may be programmed to identify this signal as an indication that the seal has been opened and that a pill has been injested by the patient. In the alternate, pill dispenser 20 ′ may be used as a capacitor in a resonant circuit. Under this approach, when the patient presses the pill dispenser 20 ′ the impendance is changed due to the skin-metal impedance change and consequently the resonanace circuit may be closed by the patient's hands. Accordingly, IMDs 10 , 10 ′ and 10 ″ are able to monitor dose data and related clinical parameters by communicating with pill dispenser 20 ′. The measurements performed by IMDs 10 , 10 ′ and 10 ″ are specific to the type of preprogrammed criteria and determinants thereof. However, in the context of the present invention, IMDs 10 , 10 ′ and 10 ″ could be programmed to monitor a given pill dispenser 20 ′ on a chronic basis. This will provide a stream of data that will indicate whether the patient has been following a prescribed dose and regimen. Further, IMDs 10 , 10 ′ and 10 ″ may be programmed to monitor the efficacy of the drug by monitoring the physiological effects of the drug on the patient. Accordingly, a direct, real time assessment and interpretation of clinical status is obtained under the communication scheme advanced by the present invention.
Referring to programmer 20 in more detail, when a physician or an operator needs to interact with programmer 20 , a keyboard coupled to Processor 80 is optionally employed. However the primary communication mode may be through graphics display screen of the well-known “touch sensitive” type controlled by graphics circuit. A user of programmer 20 may interact therewith through the use of a stylus, also coupled to a graphics circuit, which is used to point to various locations on a screen/display to display menu choices for selection by the user or an alphanumeric keyboard for entering text or numbers and other symbols as shown in the above-incorporated '362 patent. Various touch-screen assemblies are known and commercially available. The display and or the keyboard of programmer 20 , preferably include means for entering command signals from the operator to initiate transmissions of downlink telemetry from IMDs and to initiate and control telemetry sessions once a telemetry link with one or more IMDs has been established. The graphics display /screen is also used to display patient related data and menu choices and data entry fields used in entering the data in accordance with the present invention as described below. The graphics display/screen also displays a variety of screens of telemetered out data or real-time data. Programmer 20 is also provided with a strip chart printer or the like coupled to interface controller module so that a hard copy of a patient's ECG, EGM, marker channel or similar graphics display can be generated. Further, Programmer 20 's history relating to instrumentation and software status may be printed from the printer. Similarly, once an uplink is established between programmer 20 and any one of IMDs 10 , 10 ′ and 10 ″, various patient history data and IMD performance data may be printed out. The IMDs contemplated by the present invention include a cardiac pacemaker, a defibrillator, a pacer-defibrillator, implantable monitor (Reveal), cardiac assist device, and similar implantable devices for cardiac rhythm and therapy. Further the IMD units contemplated by the present invention include electrical stimulators such as, but not limited to, a drug delivery system, a neural stimulator, a neural implant, a nerve or muscle stimulator or any other implant designed to provide physiologic assistance or clinical therapy.
Data center 62 represents a high speed computer network system having wireless bi-directional data, voice and video communications with programmer 20 and/or pill dispenser 20 ′ via wireless communications link 136 . Generally data center 62 is preferably located in a central location and is preferably equipped with high-speed web-based computer networks. Preferably, data center 24 is manned 24-hours by operators and clinical personnel who are trained to provide a web-based remote service to programmer 20 and /or pill dispenser 20 ′. In accordance with the present invention, data center may be located in a corporate headquarters or manufacturing plant of the company that manufactures programmer 20 . The wireless data communications link/connections can be one of a variety of links or interfaces, such as a local area network (LAN), an internet connection, a telephone line connection, a satellite connection, a global positioning system (GPS) connection, a cellular connection, a laser wave generator system, any combination thereof, or equivalent data communications links.
As stated hereinabove, bi-directional wireless communications D , E and F act as a direct conduit for information exchange between remote data center 62 and programmer 20 , pill dispenser 20 ′ and physician center 120 , respectively. Further, bi-directional wireless communications A and B provide an indirect link between remote data center 62 and IMDs 10 , 10 ′ and 10 ″ via programmer 20 and pill dispenser 20 ′. In the context of this disclosure the word “data” when used in conjunction with bi-directional wireless communications also refers to sound, video and information transfer between the various centers.
Generally, in the context of the invention, all programmers located proximate to IMDs or patients with IMDs and distributed globally are connected to an expert data center to share software upgrades and access archived data. The programmer functions as an interface between the remotely located expert data center and the IMDs. Further, procedural functions such as monitoring the performance of the IMDs, upgrading software in the IMDs, upkeep and maintenance of the IMDS and related functions are implemented via the programmer. The preferably telemetric and yet local interaction between the programmer and the IMDs needs to be managed by a qualified operator. In order to facilitate the just-in-time patient care at the location of the patient, the invention provides pill dispenser 20 ′ that is preferably wirelessly linked to data center 62 . This scheme enables the dissemination of drug related clinical information worldwide while maintaining a high standard of patient care at reduced costs.
Although specific embodiments of the invention have been set forth herein in some detail, it is understood that this has been done for the purposes of illustration only and is not to be taken as a limitation on the scope of the invention as defined in the appended claims. It is to be understood that various alterations, substitutions, and modifications may be made to the embodiment described herein without departing from the spirit and scope of the appended claims. | A closed loop system for monitoring drug dose, intake and effectiveness includes a pill dispenser in data communications with at least one implantable medical device. The system is preferably implemented in a web-enabled environment in which a remote data center communicates with the implantable devices (IMDs) in a patient via a programmer or the pill dispenser. Th data center includes high speed computers and databases relating to patient history and device information. A physician or clinician may access the remote data center to review and monitor the IMDs remotely. More specifically, the IMDs are adapted to chronically monitor the pill dispenser to thereby log and document drug dose, patient compliance with prescriptive regimens and as well to monitor drug efficacy in the patient. The system further provides a dynamic drug management system, compatible with a web-enabled interactive data communication environment, that accurately monitors dose and specific drug effectiveness in a patient to enhance patient care. | 8 |
DESCRIPTION
Technical Field
The present invention relates to a method and apparatus for continuously determining the moisture content of grain being harvested and communicating to the operator of the harvesting equipment the moisture content.
BACKGROUND OF THE INVENTION
Grain typically is harvested by a combine which reaps the grain, threshes the a hopper. The threshed grain is then ultimately transferred from the combine's hopper to a storage bin. To prevent spoilage, of the grain in the bin, grain must be sufficiently dry prior to storage or immediately dried in the storage bin to prevent spoilage. If the moisture content of freshly harvested grain is too high, then it requires significant energy to dry the same. Obviously it is desirable to harvest at the lowest possible moisture conditions to reduce cost of drying.
Grain dryers such as those disclosed
in U.S. Pat. No. 4,599,809 and U.S. Pat. No. 4,750,273 disclose a method and a system utilizing heat to dry freshly harvested grain to a desired moisture content. However, the process of drying wet grain is expensive because of the energy required to heat the grain, as well as the energy required to operate electrical equipment necessary to circulate and sample the grain. For this reason it is desirable to harvest grain with a moisture content as close as possible to that of the desired storage level and thereby minimize the amount of drying required.
In the past, farmers would visually inspect the fields, and harvest what appeared to be the driest portions of their fields first. However, because the moisture content of the grain in the field can vary greatly, this method is inherently inaccurate. For a more accurate measurement, farmers would harvest a small section and then use a hand held moisture sensor to determine the moisture content of grain in the combine's hopper. This required the farmer to stop the combine, climb out of its cab, climb up to the hopper and obtain a sample full of grain to be put through the moisture sensor. This was not only time consuming but also inaccurate since dry grain could be mixed with that having a higher moisture content and could lead to inaccurate measurements.
Other combine moisture sensors are designed to accumulate a hopper full of grain from an entire test plot and give a moisture reading of the entire hopper. Once again, this does not yield continuous moisture data to the operator of a combine to determine the desirability of harvesting grain.
The present invention solves these and other problems by allowing the operator of the combine to continuously sample the grain for moisture content without leaving the cab.
Further, the moisture sensor could be replaced by a different type of sensor to qualitatively measure other characteristics of grain such as oil content, protein content, test weight, foreign matter, starch content, sugar content and other qualitative measurements. This data may be similarly reported to an operator of a combine continuously during harvesting.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus for determining the desirability of harvesting grain. According to the present invention the moisture content of grain being harvested is continuously monitored by a grain moisture sensor mounted on a combine. The combine reaps and threshes the grain and transports the threshed grain to a hopper. The moisture sensor may be mounted or located in one of a series of augers or elevators that moves threshed grain from the thresher to the hopper. The grain moisture data are reported to the operator of the combine so that the operator may have continuous monitoring and thus harvest the grain having an optimal moisture content.
The moisture sensor could be replaced by sensors for sensing different characteristics of grain without departing from the scope of this invention.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is an elevational view of a conventional combine;
FIG. 1A/shows a schematic representation of the system of the present invention;
FIG. 2 is a schematic representation of a conventional grain transfer member a combine;
FIG. 3 is an isometric view of a grain sample cell;
FIG. 4 is an elevational view of a conventional capacitance-type moisture sensor;
FIG. 5 is an elevational view of an auger tube having a sample cell appended thereto;
FIG. 6 is a sectional view taken along the lines 6--6 of FIG. 4;
FIG. 7 is another embodiment of a sample cell appended to a section of auger tubing;
FIG. 8 is a schematic representation of a moisture sensor inserted into an auger having a section of the auger flighting removed to accommodate the moisture sensor;
FIG. 9 is a schematic representation of the fill auger tube having a section of the flighting replaced with paddles and an auger tube that has a chute facing substantially upward.
FIG. 10 is another embodiment of a moisture sample cell with a sample return to the thresher;
FIG. 11 is a diagrammatic view of a spring operated batch sampling moisture cell;
FIG. 12 is a diagrammatic view of another spring operated batch sampling moisture cell;
FIG. 13 is a diagrammatic sectional view of another moisture sample cell;
FIG. 14 is a cross sectional view of a cylindrical capacitance electrode disposed within an auger tube;
FIG. 15 is an elevational view of
a conventional double plate capacitance probe.
DETAILED DESCRIPTION
While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail a preferred embodiment of the invention. The present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to embodiments illustrated.
FIG. 1 shows a conventional combine 10 having an operator's cab 11, a reaper 12, a thresher 14, a hopper 16, and a transport member 18 that carries the grain from an output of the thresher 14 to the hopper 16. The hopper 16 may either be onboard the combine 10 or be a wagon pulled behind or alongside the combine 10.
Generally the reaper 12 gathers grain-bearing plants from a field and conveys the plants into the thresher 14. The thresher separates grain from the grain-bearing plants and deposits the separated grain into a lower portion 20 of the combine 10. Grain typically, includes corn, wheat, soybeans, oats, rice, flax, barley, canola, rape, rye, beans, milo (sorghum), peas, forage and turf seeds, sunflower seeds and vegetable seeds.
FIG. 1A shows a schematic diagram of a system 300 for calculating and displaying grain moisture content being harvested by combine 10. The system comprises a central processing unit 302 that is preferably mounted in the operator's cab 11 and capable of calculating and displaying the moisture content of grain being harvested 304, and the temperature of grain being harvested 306. Necessarily, the central processing unit 302 must be responsive to signals from a means for measuring the moisture content of grain being harvested 308, and a means for measuring the temperature of grain 310 being harvested. Output port 312 is provided for interfacing to a printer or other devices. Preferably, the port is of a conventional type such as the RS232.
The central processing unit 302 may be adapted to be responsive to signals from sensors that sense other characteristics of grain and to process these signals to provide valuable information to an operator of a combine.
The CPU 302 also includes input means 314, such as a keypad, so that the operator may select, for example, the type of grain being harvested so that the proper temperature compensation data may be used.
According to the invention, a moisture sensor assembly 22 may be provided in the combine. (The combine 10 could also be a sheller or nonmobile threshing machine.) Preferably the moisture sensor assembly 22 is placed in the grain transport member 18 or adjacent the grain transport member because the grain is necessarily volumetrically concentrated and continuously moving to provide a homogeneous sample.
For example, FIG. 2 schematically discloses a conventional transport member 18 having a draw auger 24 enclosed within a draw auger tube 26, a first grain transfer bin 27, a grain elevator 28, a second grain transfer bin 29, and a fill auger 30 enclosed within a fill auger tube 32. Draw auger 24 transports grain inside the draw auger tube 26 from a lower portion 20 of combine 10 to the first grain transfer bin 27. Grain elevator 28 transports the grain from the first bin 27 to the second grain transfer bin 29. Fill auger 30 transports the grain inside the fill auger tube 32 from the second bin 29 to the hopper 16 for temporary storage until it is unloaded into a wagon or truck for transfer to a storage bin.
In the first embodiment of the present invention, the moisture sensor assembly 22 comprises a sample cell 34 as shown in FIG. 3 and a moisture sensor 36 more clearly shown in FIG. 4. The moisture sensor 36 has a plate 48 which detachably mounts onto the sample cell 34. The moisture sensor 36 includes a grain temperature sensor 35 to measure the temperature of a grain sample for compensation of the measured dielectric constant which is affected by the temperature of the grain sample. The moisture sensor assembly 22 is attached to the draw auger tube 26 so that the sample cell 34 may receive a continuous flow of grain from the draw auger tube 26 so that the grain will fill the cell 34 and the moisture content may be continuously measured.
Sample cell 34 is substantially rectangular in shape having four walls 38, a top opening 40, a bottom opening 42, and a chamber 44 therebetween inter-connecting the top and bottom openings 40 and 42. A portion of each wall 3 of sample cell 34 inwardly tapers 46 proximate the bottom opening 42 so that the bottom opening 42 is smaller than the top opening 40. Taper 46 restricts a flow of grain through the sample cell 34 to ensure a full measure of grain for each sample to provide a more accurate capacitance measurement.
The moisture sensor 36 has a single plate 48 which forms with the walls 38 of the cell 34, a capacitance type sensor. The moisture sensor 36 has its single sensor plate 48 connected to a digital moisture meter 50 of conventional design. The wall 38 of the cell 34 is also connected to the moisture meter 50. The function of the moisture meter 50 may be accomplished by the CPU 302. The CPU 302 is controlled by a conventional microprocessor such as a 65C02.
The moisture meter 50 is calibrated using air as a reference dielectric which is compared to the capacitance of the grain forming the dielectric. The meter 50 also preferably employs temperature compensation circuitry that is connected to the grain temperature sensor 35 which adjusts the moisture content in relation to the sample temperature. Discussion of this measurement technique is found in U.S. Pat. Nos. 4,559,809 and 4,750,273, described above, and is incorporated herein by reference.
The temperature compensation varies with different types of grains being harvested because the temperature coefficients of the grains vary when measured by capacitance. Accordingly, the temperature coefficients of various grains are entered into the CPU 302 before harvesting. The operator of the combine 10 selects the appropriate type of grain before harvesting to attain more accurate temperature compensation and more accurate moisture content data.
One of the walls 52 of the sample cell 34 has a facial portion removed to form a longitudinally extending slot 54. Slot 54 is adapted to receive the sensor plate 48, centrally. Moisture sensor 36 mounts on the sample cell 34 to form the moisture sensor assembly 22. Sensor plate 48 fits into the slot 54 and extends into the chamber 44 of the sample cell 34 so that the sensor plate 48 may contact grain flowing through sample cell 34 to measure the grain moisture. The walls 38 of the sample cell 34 are made of a conductive material such as metal so that the walls 38 will serve as a second capacitance plate.
A portion of draw auger tube 26 is removed to form an opening 56. Moisture sensor assembly 22 is attached to a lower portion 58 of the draw auger tube 26 (FIG. 5), so that the top opening 40 of the sample cell 34 is in alignment with the tube opening 56 to provide a continuous flow of grain through the sample cell 34.
As grain moves through the draw auger tube 26 a portion of the grain falls through the tube opening 56 and through the sample cell 34. The flow of grain is restricted by the smaller bottom opening 42 of the sample cell 34, thereby providing a full measure of grain continuously in the sample cell 34 and surrounding the sensor plate 48. The sensor plate 48 serves as one blade of a capacitor while the walls 38 of the sample cell 34 adjacent the sensor plate 48 serve as the second capacitance plate.
The capacitance of the sample cell 34, as measured by the meter 50, is varied by the dielectric constant of any material that is present in the sample cell 34. The dielectric constant varies, for the most part, with the type of grain and the moisture content of the grain. The moisture meter 50 is operative to relate the moisture content of a sample of grain to the capacitance of the sample cell 34 with the sample therein. This is displayed on a meter in the cab 11 of combine 10, or on a more permanent record.
A second embodiment of the present invention involves a similar set-up as described above, but the moisture sensor assembly 22 is attached to the fill auger tube 32, or located at the lower portion of the combine 20, or in the first or second grain transfer bins 27, 29 or in the grain elevator 28.
A third embodiment of the present invention provides for attachment of the moisture sensor assembly 22 on the fill auger tube 32 within the hopper 16. Inasmuch as the sample cell 34 is inside the hopper 16 and may be surrounded by grain, additional housing must be provided to allow for continuous batch sampling.
FIG. 7 shows a portion of fill auger tube 32 having a sample cell housing 60 appended at a lower portion 62 of the fill auger tube 32. Sample cell housing 60 is substantially rectangular in shape defining a void 64. A rectangular sample chamber 66 having walls 67, an upper and lower opening 68, 70, mounts to the sample chamber housing 60 within the void 64. A top portion 72 of the sample chamber housing 60 tapers 75 inward and upward, terminating at an attachment member 76.
The attachment member 76 is adapted to attach to a circumferential portion of the auger tube 32. The attachment member 76 defines a channel 78 opening into the upper opening 68 of the sample chamber 66. Channel 78 is in alignment with a hole 79 cut in the fill auger tube 32 to provide a flow of grain through the sample chamber 66.
A portion 81 of walls 67 has a longitudinally extending slot 54 adapted to receive the sensor plate 48 to provide moisture measurement of grain in the sample chamber 66.
A rotatable semicircular disk 80 closes off the lower opening 70 of sample chamber 66 thereby blocking the flow of grain through the sample chamber 66 to permit a full sample of grain to accumulate around the sensor plate 48. The disk 80 is motor driven through a gearbox (not shown) that rotates the disk to permit discharge of the grain sample into the hopper 16 or the void 64 after the moisture content has been measured.
Even though the sample chamber housing 60 sits within the hopper 16 and grain fills up around the outside, the void 64 is of sufficient volume to allow continuous batch sampling throughout a harvest procedure until the onboard hopper 16 is full.
A fourth embodiment of the present invention provides for attaching the moisture sensor 36 onto the draw auger tube 26 (FIG. 6). A portion of the sensor plate 48 extends into the draw auger tube 26 to be in direct contact with grain as it flows through the draw auger tube 26. FIG. 8 shows a portion of draw auger 24 having flighting 82 enclosed within the draw auger tube 26. A portion 84 of the flighting 82 is removed in order to form a sample area 85. (It is also possible to put moisture sensor 36 at an end of the draw auger 24 so that it is not necessary to remove a section of the flighting 82.) A portion of draw auger tube 26 is removed proximate the sample area 85 to form a bore 86 to receive the sensor plate 48.
The moisture sensor 36 is attached to the outside of the draw auger tube 26 and the sensor plate 48 is inserted into bore 86 so that the sensor plate 48 may continuously contact grain in the sample area 85. Sensor plate 48 and a portion 87 of the draw auger tube 26 adjacent the sensor plate 48 serve as the two capacitor plates to measure the moisture content of the grain passing through the draw auger tube 26. The moisture content is continuously displayed in the cab 11 of the combine 10, or permanently recorded.
A fifth embodiment of the present invention is similar to the fourth embodiment, but the sensor plate 48 is located inside the fill auger tube 32 or the lower portion of the combine 20, or in the first or second grain transfer bins 27, 29 or in the grain elevator 28.
FIG. 9 shows a sixth embodiment of the present invention. A substantially L-shaped chute 90 has first and second ends 92, 94. The first end 92 is adapted to fit over and attach to an endmost portion 96 of the fill auger tube 32 located within the hopper 16. The second end 94 of the chute 90 faces substantially upward.
Preferably, the flighting 82 at the end of the fill auger 30 is removed and replaced with paddles 100 adjacent the second end 94 of the chute 90. A moisture sensor 36 is mounted on an inner portion 102 of the chute 90 at the second end 94 of chute 90 above the paddles 100. A portion of sensor plate 48 extends into chute 90 where it is in continuous contact with the grain flowing through the chute 90.
Paddles 100 rotate along with fill auger 30 and push grain upward filling the chute 90 with grain and across the sensor plate 48 and out through the second end 94 of chute 90 and into the hopper 16. The inner portion 103 of the chute 90 immediately adjacent the sensor plate 48 serves as the second capacitance plate, and moisture measurement is accomplished as described above.
FIG. 10 shows another embodiment of the moisture sensor assembly 22. A substantially circular sample cell 104 has walls 105, a grain inlet 106 and a grain outlet 108. The grain inlet 106 is in alignment with the fill auger tube opening 79 to permit a continuous flow of grain through the sample cell 104. The sample cell 104 may be mounted anywhere on the fill auger tube 32 where the cell 104 will receive a measurable quantity of grain. The walls 105 of sample cell 104 taper 110 inward and downward proximate the grain outlet 108 of the sample cell 104 to restrict the flow of grain through the sample cell 104.
A tube 112 has first and second ends 114, 116 respectively. The tube 112 is preferably two to three inches in diameter and made of plastic. The first end 114 of the tube 112 is adapted to fit over the grain outlet 108. The second end 116 is in grain communication with the grain thresher 14 to return sampled grain to the thresher 14. It is equally possible to return the grain to any point along the grain transport member 18. (The grain thresher 14 and the transport member 18 may be collectively referred to as a grain processing stream.) Therefore, the moisture content of grain may be continuously monitored throughout the entire harvest procedure and the sampled grain returned to the thresher 14.
FIG. 11 shows another embodiment of the moisture sensor assembly 22. A hollow pipe 118 having a grain inlet 120 and a grain outlet 122 is attached to a portion 124 of fill auger tube 32. The grain inlet 120 is in alignment with the hole 79 cut in the fill auger tube 32 to provide a flow of grain through the pipe 118. The moisture sensor 36 is positioned proximate the grain outlet 122, and reports grain moisture data as discussed above.
A spring loaded closure mechanism 126 is provided proximate the grain outlet 122 to allow for either closure of the grain outlet 122 or to restrict a flow of grain flowing through the pipe 118. The closure mechanism 126 comprises a spring 128 attached to an outside portion 130 of a flapper valve 132. The spring 128 has a tension that may be overcome by a predetermined amount of grain thereby allowing the flapper valve 132 to open and discharge a sample of grain. The spring 128 has sufficient tension to return the flapper valve 132 into a closed position to close off the grain outlet 122 or to nearly close the outlet 122 to substantially restrict the flow of grain through the pipe 118.
A hose 134 has its first end 136 adapted to fit over an endmost portion 138 of the pipe 118. The second end 140 of the hose 134 is in grain communication with the thresher 14 and returns sampled grain to the thresher 14. The grain may also be returned to any point along the grain transport member 18.
FIG. 12 shows another embodiment of the moisture sensor assembly 22. A plastic saddle 150 has a grain inlet 152 and grain outlet 154. The grain inlet 152 is in alignment with the fill auger tube hole 79 to permit a flow of grain through the saddle 150. A housing 156 has walls 158 that define a void 160. A sample chamber 162 having first and second ends 164, 166 is mounted to the housing 156 inside the void 160. The first end 164 of the sample chamber 162 is adapted to fit over the grain outlet 154 of the saddle 150 to provide a flow of grain into the sample chamber 162.
A flapper valve 168 having a lip 169 at its distal end is hingedly connected to the sample chamber 162 and is movable from an open position to a closed position by a closure spring 170 to permit a sample of grain to accumulate in the sample chamber 162. Moisture sensor 36 is attached to a portion 171 of a chamber wall 172 proximate the second end 166 to measure the moisture content of a grain sample as discussed above.
The opening and closing of the flapper valve 168 is controlled by a valve latch 174 operated by a latch spring 175 and an electromagnet 176. A latch arm 178 has a first end 180 attached to the chamber wall 171, and a second end 182 has a roller 183. An intermediate portion 184 of the latch arm 178 is responsive to magnetism.
The flapper valve 168 is held shut when the latch arm 178 is forced outward by the latch spring 175 causing the roller 183 to engage the lip 169 of the flapper valve 168 thereby holding the flapper valve 168 shut.
To open the flapper valve 168, a current is provided to the electromagnet 176 attracting the responsive portion 184 of the latch arm 178. The electromagnet has a sufficient magnetic field to overcome a tension in the latch spring 175 thereby moving the roller 183 away from the lip 169 of the valve 168. The weight of the grain in the chamber 162 is then sufficient to overcome a tension in the closure spring 170 forcing the valve 168 open and discharging the contents of the chamber 162.
The valve 168 is returned to the closed position by the closure spring 170 providing sufficient tension to reset the valve 168. The current to the electromagnet 176 is then shut-off allowing the latched spring 175 to push the latch arm 178 outward so that roller 183 may engage lip 169 and hold the flapper valve 168 closed to accumulate another sample of grain.
It should be understood that sample cells of differing shapes and dimensions other than those described above are contemplated by this invention. Further, it is contemplated that a sample cell may be opened and shut by various power closure means or devices such as motors, solenoids, gravity, hydraulics, pneumatics, and hand activated controls.
FIG. 13 shows a cylindrical sample cell 190 that may be attached to either the fill auger tube 32 or draw auger tube 26 as described above. The cylindrical sample cell 190 functions as a capacitor and is more fully described in U.S. Pat. Nos. 4,559,809 and 4,750,273 and is incorporated herein by reference.
The sample cell 190 is a cylindrical capacitor which is connected to the capacitance digital moisture meter 50. The cell 190 includes an inner conductive cylindrical electrode 192 positioned coaxially within an outer conductive cylindrical electrode 194, thereby defining an annular active region 196 of the cell 190. The sample cell 190 has a grain inlet 198 into the annular active region 196 and a sample cell closure means 200 more fully disclosed in the above incorporated patents.
The sample cell 190 is mounted to either the draw auger tube 26 or fill auger tube 32 or anywhere between the thresher 14 and the hopper 18 so that grain inlet 198 is in alignment with the tube openings 56 and 79 to provide a flow of grain into the annular active region 196 of the sample cell 190. The grain moisture measurement is more fully described in the above referenced patents.
FIG. 14 shows a variation of the above described cylindrical capacitance cell 190. The inner capacitance cell 192 is mounted inside either the draw auger tube 26 or fill auger tube 32 in the sample area 85 provided by removing a section of auger flighting 82. An annular portion 202 of the auger tube 26 or 32 immediately adjacent the inner cylindrical capacitance electrode 192 serves as the second conductive electrode 204. Annular active region 196 lies between the electrode 204 and the inner cylindrical electrode 192. The capacitance of a grain sample in the annular active region 196 is measured as described above.
It should be understood that the present invention contemplates measuring the moisture content of grain anywhere during transportation of grain from the thresher 14 to the hopper 16 and reporting the moisture content to a display in the cab 11 or elsewhere. The moisture content may be measured continuously; periodically over a preselected or random time interval; or on demand throughout an entire harvest procedure. Preferably, several moisture content readings are taken and averaged by the CPU 302 and displayed. The moisture content data may be reported, recorded, or transmitted by any usual means such as radio frequency, sonic, optical, wires, wireless, or electromagneticly. The moisture data may be used for any means such as displays, printouts, magnetic records, memory devices, analog meters, warning devices, inputs into other controls, and/or used to make adjustments in the combine machinery.
Further, it is contemplated that the grain may be transferred by means other than a combination of augers and elevators. For example, grain may be pushed or pulled through a tube with air or grain may be transferred by conveyors or other means.
It should also be understood that the present invention contemplates measuring the moisture content by any method that yields accurate moisture content data, and should not be limited to only measurement by capacitance. For example, moisture content may be measured by optical, infrared, sound, microwaves, heat or conductance.
One advantage of the present invention is that the moisture sensor 36 may be readily retrofitted to currently existing combines to provide grain moisture data to the operator of the combine 10. The embodiments utilizing sample cells may be easily attached to an existing combine by simply cutting an opening in an auger tube and attaching the sampling cells described above. Obviously, the capacitor plate 48 can be mounted in an auger tube by removal of a section of flighting.
Those embodiments utilizing a sample cell are more advantageous in that they resist accumulation of foreign materials. In combining beans and similar crops which are close to the ground, dirt is picked up and tends to accumulate on the inside of an auger tube in the clearance between the flighting and the inside wall of the tube. This will tend to short out the sensor plate or provide inaccurate readings. The continuous sampling cell does not have this disadvantage. In addition, two sensor plates spaced and insulated from each other may be utilized in lieu of using the auger tube or cell wall as a second plate.
It is further contemplated that the moisture sensor may be replaced by a grain sampler or sensor for sensing various characteristics of grain such as oil content, test weight, foreign matter, starch content, protein content, sugar content or other qualitative measurements.
While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention and the scope of protection is only limited by the scope of the accompanying claims. | A method and an apparatus for determining the moisture content of grain to be harvested comprising the steps of reaping grain from grain bearing plants, threshing grain from the grain bearing plant, collecting the threshed grain in a hopper, and sensing the moisture content of the threshed grain prior to collection of the grain in the hopper. | 0 |
This is a continuation of application Ser. No. 886,619, filed July 18, 1986, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a safe, non-resealable vent closure for galvanic cells, such as nonaqueous liquid oxyhalide cells, and more particularly to an improved vent liner and cell cover for such cells.
Reliable, long service life cells or batteries have been developed for portable electrically powered devices such as tape recorders, playback machines, radio transmitters and receivers. Electrochemical cell systems for such devices provide a long service life by utilizing highly reactive anode materials such as lithium, sodium and the like, in conjunction with high energy density nonaqueous liquid cathode materials and suitable salts, often referred to as cathode-electrolytes.
Galvanic cells typically are sealed to prevent loss of electrolyte by leakage. This is especially important in the case of nonaqueous liquid cathode cells, which typically employ highly reactive oxyhalide or halide cathode-electrolytes. Any escape of such liquids, or their reaction products, could cause damage to the device employing the cell, or to the surface of a compartment or shelf where the cell is stored.
On the other hand, certain operating conditions can cause the internal pressure of such liquid cathode cells to markedly increase. This pressure can be caused by external sources, such as fire, or internal sources, such as heat generated during charging. In certain situations, the anode can melt and react directly with the liquid cathode in a vigorous, energy-releasing reaction. In the case of other galvanic cells, such as alkaline-zinc cells, carbon-zinc cells, etc., such cells may generate large quantities of gas under certain conditions of use. Thus, if any of the foregoing cells were permanently sealed, the build up of internal pressure within the cell could cause the cell container to leak, bulge or even rupture, which can cause property and/or bodily damage.
It is therefore necessary to provide a vent for galvanic cells that is designed to remain sealed during normal operating conditions which the cell may encounter, but which will open when the pressure within the cell substantially increases. In the case of liquid cathode cells employing, for example, a lithium anode, the vent must open before the lithium melts and reacts directly with the liquid cathode. Upon venting, most of the liquid cathode material is removed and is thus unavailable for reaction with the anode.
One type of vent assembly previously used for lithium-oxyhalide cells comprises a vent liner of a material such as polytetrafluoroethylene inserted into an orifice in a cell cover, with a seal member such as a glass ball forced into the orifice of the liner to seal the cell. Upon build up of a predetermined pressure within the cell, the seal member will be at least partially expelled from the liner orifice, thereby forming a permanent vent to the atmosphere. In manufacturing such a vent assembly, an orifice typically is formed by punching a hole in the cell cover. Thereafter, the liner is inserted in the cell cover orifice. Preferably, the liner is flanged on its upper edge so that it will be accurately positioned upon insertion into the cell cover orifice. After insertion, the flange abuts the upper surface of the cover, and a portion of the liner may extend beyond the bottom surface of the cover into the cell interior. Since the punching operation leaves a rough edge at the intersection of the walls of the orifice and the top of the cover, which could detrimentally score the liner, the liner is not forced or press-fitted into the cell cover orifice to provide a tight fit.
Punching out the hole in the cell cover to create an orifice into which the vent liner is inserted results in the orifice being outwardly tapered toward the bottom of the cell cover. As a result, a crevasse will exist between the cell cover and the vent liner. This crevasse will fill with cathode electrolyte fluid when the cell is filled. In consequence, an undesirable electrochemical cell system is created between the lithium in the cell, and oxygen or water vapor, or both, present in the atmosphere directly outside the cell cover. The lithium is oxidized according to:
Li→Li.sup.30 +e.sup.31
The lithium ions will diffuse out of the cell through the electrolyte contained in the crevasse and at the vent liner/cover interface, whereupon atmospheric water and oxygen are reduced according to:
1/2 O.sub.2 +H.sub.2 O+2Li.sup.+ +2e.sup.- →2LiOH
2LiOH+CO.sub.2 →Li2CO3 +1/2 H.sub.2.
One or more of these products, which are formed on the exterior of the cell cover, can be extremely corrosive, and in combination with the driving potential of the undesirable electrochemical cell system, could cause leakage of the cell to accelerate with time and could also cause short-circuiting of the cell.
SUMMARY OF THE INVENTION
This invention employs a novel cell construction comprising a cell container which has a vent liner containment section that includes a sealing well having a bottom disposed toward the interior of the cell, an orifice in the sealing well and a support ledge at the bottom of the sealing well. A vent liner having a vent liner orifice is disposed within the sealing well so that an end of the vent liner abuts the support ledge, so as to provide a path from the interior of the cell to the atmosphere via the sealing well orifice and the vent liner orifice. A seal member is force-fitted within the vent liner, and the vent liner and the seal member are adapted so that the seal member will be at least partially expelled from the vent orifice at a predetermined gas pressure within the cell.
During manufacture, the support ledge provides a positive stop against which the vent liner cannot be further inserted, thereby eliminating the need for a flange at the top of the vent liner. In addition, if the sealing well has a relatively smooth wall, as is produced by forming the sealing well from a smooth sheet of material by metal forming methods, then creation of intimate contact between the vent liner and the sealing well results in the elimination of a crevasse between the cell cover and the vent liner, thereby effectively eliminating the path for diffusion of lithium ions to the outside of the cell. A sealant can be disposed at the interface of the sealing well and the vent liner to fill any surface imperfections at these interfacial surfaces. Certain other novel structural features and manufacturing techniques can be advantageously employed in connection with this invention, as is explained more fully below.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a vertical cross sectional view of an electrochemical cell made in accordance with the present invention.
FIG. 2 is a horizontal cross-sectional view taken along line 2--2 of FIG. 1.
FIG. 3 is an enlarged vertical cross sectional view of the cell cover and the cell container of the electrochemical cell shown in FIG. 1, which shows in detail the cell cover and the vent liner of the cell.
FIGS. 4A, 4B and 4D respectively are top, side and perspective views of a type of anode spring collector usable in a cell made in accordance with the present invention. FIG. 4C is a perspective view of the material stock used to form the spring collector shown in FIGS. 4A, 4B and 4D.
FIGS. 5A-5F are side views of the cell cover during stages of its manufacture.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring in detail to FIG. 1, there is shown a cross-sectional view of a cylindrical cell. The cell depicted is a nonaqueous electrochemical cell comprising an anode, a cathode collector and a liquid cathode-electrolyte.
The cathode-electrolyte comprises a solution of an ionically conductive solute dissolved in an active cathode depolarizer. The cathode depolarizer can be a liquid oxyhalide of an element of Group V or Group VI of the Periodic Table, such as sulfuryl chloride, thionyl chloride, phosphorus oxychloride, thionyl bromide, chromyl chloride, vanadyl tribromide and selenium oxychloride. Also usable as a cathode depolarizer is a halide of an element of Group IV to Group VI of the Periodic Table, such as sulfur monochloride, sulfur monobromide, selenium tetrafluoride, selenium monobromide, thiophosphoryl chloride, thiophosphoryl bromide, vanadium pentafluoride, lead tetrachloride, titanium tetrachloride, tin bromide trichloride, tin dibromide dichloride and tin tribromide chloride.
The solute for use in the cathode electrolyte can be a simple or double salt which will produce an ionically conductive solution. Preferred solutes for nonaqueous systems are complexes of inorganic or organic Lewis acids and inorganic ionizable salts. Typical Lewis acids suitable for use in conjunction with liquid oxyhalide cathode depolarizers include aluminum fluoride, aluminum bromide, aluminum chloride, antimony pentachloride, zirconium tetrachloride, phosphorous pentachloride, boron fluoride, boron chloride and boron bromide. Ionizable salts useful in combination with the Lewis acids include lithium fluoride, lithium chloride, lithium bromide, lithium sulfide, sodium fluoride, sodium chloride, sodium bromide, potassium fluoride, potassium chloride and potassium bromide.
If desired, and specifically for the halides, a cosolvent can be added to the cathode-electrolyte to alter the dielectric constant, viscosity or solvent properties of the solution to achieve better conductivity. Some examples of suitable cosolvents are nitrobenzene, tetrahydrofuran, 1,3-dioxolane, 3-methyl-2-oxazolidone, propylene carbonate, qamma-butyrolactone, sulfolane, ethylene qlycol sulfite, dimethyl sulfite, benzoyl chloride, dimethoxyethane, dimethyl isoxazole, diethyl carbonate, sulfur dioxide and the like.
The cell housing of FIG. 1 comprises a cylindrical cell container 2 having an open end that is closed by a cell cover 40. A cathode collector shell 4 is in contact with the inner upstanding circumference of the cell container 2, thereby adapting the container 2 as the cathodic or positive terminal for the cell. Exposed within and in contact with the inner circumference of cathode collector 4 is a separator liner 6 with a bottom separator or disk 10. If desired, the cathode collector material could be extruded within the container 2, rolled with the container material or composed of one or more segments to form a cylindrical tube thereafter placed in the container.
A two-member anode 12 shown in FIGS. 1 and 2 comprises a first half cylindrical annular member 14 having flat end faces 16 and 18 and a second half cylindrical annular member 20 having flat end faces 22 and 24. When the flat end faces of each cylindrical half member are arranged in an opposing fashion, as shown in FIGS. 1 and 2, an axial cavity 26 is defined between the cylindrical half annular members 14 and 20.
Cathode collector shell 4 has to be electronically conductive so as to permit external electrical contact to be made with the active cathode material and also to provide extended area reaction sites for the cathodic electrochemical processes of the cell. Materials suitable for use for cathode collector shell 4 are carbon materials and metals such as nickel, with acetylene black being preferable. In addition, cathode collector shell 4, if made of a particulate material, should be capable of being molded directly within container 2 or capable of being molded into variously sized discrete bodies that can be handled without cracking or breaking. If cathode collector shell 4 is fabricated from a carbonaceous material, a suitable binder, with or without stabilizers, can be added to the cathode collector materials. Suitable binders for this purpose are vinyl polymers, polyethylene, polypropylene, polyacrylics, polystyrene and the like. For example, polytetrafluoroethylene would be the preferred binder for cathode collector shell 4 if the cell shown in FIG. 1 were used with a liquid oxyhalide cathode. The binder, if required, should be added in an amount between about 5% and about 30% by weight of the molded cathode collector shell 4, since an amount less than 5% would not provide sufficient strength to the molded body, while an amount larger than 30% would wetproof the surface of the carbon and/or reduce the available surface of the carbon, thereby reducing the activation site areas available for the cathodic electrochemical process of the cell. Preferably, the binder should be between 10% and 25% by weight of the cathode collector shell 4. It is important that the materials selected for cathode collector shell 4 be chemically stable in the cell in which they are to be used.
Anode 12 is a consumable metal and can be an alkali metal, an alkaline earth metal, or an alloy of alkali metals or alkaline earth metals with each other and other metals ("alloy" as used herein includes mixtures, solid solutions such as lithium-magnesium, and intermetallic compounds such as lithium monoaluminide). The preferred materials for anode 12 are the alkali metals, particularly lithium, sodium and potassium. For the cell shown in FIG. 1, it is particularly preferred to make anode 12 of lithium, in conjunction with a liquid cathode of sulfuryl chloride, thionyl chloride, or mixtures thereof.
If desired, arcuate type backing sheets 15 and 17 can be disposed against the inner surface wall of the anode bodies 14 and 20, respectively, to provide uniform current distribution over the anode. This will result in a substantially uniform consumption or utilization of the anode, while also providing a substantially uniform spring pressure over the inner wall surface of anode 12.
Referring to FIGS. 1 and 3, cylindrical cover 40 comprises a circular cover orifice 60, vent liner containment section 70, annular cap section 80 and circumferential cover flange 90. Vent liner containment section 70 comprises circumferential support ledge 72, cylindrical sealing well 74 and rounded containment section shoulder 76. Circumferential support ledge 72, which is integrally joined to sealing well 74 at the bottom of sealing well 74, is inwardly directed throughout its circumference toward the geometric axis of sealing well 74, thereby defining cover orifice 60. Rounded containment section shoulder 76 is located at the intersection of the top of sealing well 74 and cover ledge 77, the latter being the horizontal surface spanning the area between shoulder 76 and cap section 80. Rounded containment section shoulder 76 provides a smooth transition at that intersection without sharp edges. The cover is tightly sealed by conventional closing methods to container 2 with insulating gasket 52 therebetween.
It is preferred that cover 40 be formed by drawing a section of sheet metal, preferably a sheet of stainless steel. The cover orifice 60 can be formed in cover 40 by conventional punching or drilling. The specific steps taken to fabricate cover 40 are discussed in greater detail below.
Cylindrical vent liner 29, which has a vent liner orifice 25 connecting its two circular ends, is positioned in cover 40 so that one of its ends abuts support ledge 72 and its cylindrical surface is in contact with the inner surface of sealing well 74. While it is preferred for support ledge 72 to be continuous about the circumference of sealing well 74 so as to minimize the potential for an undesired electrochemical cell system arising between the inside of the cell and atmospheric constituents, support ledge 72 can also comprise one or more inwardly projecting tabs or segments sufficient to provide a ledge against which vent liner 29 can abut.
Because the metal forming procedures that can be used to fabricate cover 40 leave the inner surface of sealing well 74 relatively smooth, intimate contact between vent liner 29 and sealing well 74, which is produced as described below, will substantially prevent the transport of any lithium ions from inside the cell to the outside of the cell cover. In this way, the undesired electrochemical cell system previously developed at the interface between the vent liner and the cover no longer arises, and corrosion of the cell via such a mechanism is prevented.
Vent liner 29 can be formed from (1) a sheet material molded to shape during the process of force-fitting a seal member into the orifice of vent liner 29; or (2) a tube fabricated to a suitable length, the latter being preferred. The material from which vent liner 29 is made can be resilient or non-resilient, but must be both resistant to attack by the electrolyte and not react with a seal member force-fitted therein so as to substantially alter the pressure at which the force-fitted seal member is ejected from the vent liner 29. It is presently preferred that vent liner 29 be a molded vent liner of Tefzel®, available from E.I. Du Pont de Nemours & Co., Wilmington, Del., although other materials are suitable, such as polyethylene, polytetrafluoroethylene, perfluoroalkoxy polymer, fluorinated ethylene-propylene polymer, glasses, etc.
As stated above, a seal member is force-fitted into vent liner orifice 25 to seal the cell. This seal member preferably has a smooth spherical configuration, as exemplified by ball 56 in FIGS. 1 and 3. Ball 56 can be made of a resilient or non-resilient material such as metal, glass, ceramic, or plastics, and is made of a material or coated with a material that is chemically resistant to the cell s components, particularly the cell's liquid components. If ball 56 is resilient, it can be made from polytetrafluoroethylene, fluorinated ethylene-propylene copolymer, perfluoroalkoxy polymer, ethylene-tetrafluoroethylene copolymer or other selected fluoropolymers. When ball 56 is to be coated with a chemically inert material, it can then be made of any material.
It is preferred that the outer periphery of cover 40 be bent through an obtuse angle, preferably through one approaching or equal to 180 degrees, to provide cover flange 90, as shown in FIGS. 1 and 3. Such a construction, also called a "roll-back" construction, provides a tight seal between cover 40 and cell container 2, since flange 90 upon assembly is compressed against gasket 52, which causes flange 90 to "follow" gasket 52 if any dimensional changes to the cell occur from thermal expansion and/or contraction.
An electrically conductive spring strip 28, whose legs 32 and 34 are biased against the two screen-backed anode members 14 and 20, is electrically connected to cell cover 40 so as to make cover 40 the anodic or negative terminal of the cell. The ends of spring legs 32 and 34 can be electrically connected to cover 40 by welding the ends to cover 40. Alternatively, the geometric configuration of cell cover 40 when made in accordance with this invention allows use of a novel connection system. Referring to FIGS. 4A through 4D, there is shown a unitary spring collector assembly 420, comprising spring strip 28 and an annular fastening disk 401. Disk 401 is made of a resilient material, such as stainless steel. The spring legs 32 and 34 of spring strip 28 are joined, as by welding, in region 402. Disk 401 contains a castellated fastening hole 403, having four downwardly bent, radially and inwardly directed tabs 406 spaced at equal intervals about the circumference of hole 403 so as to define four radially directed slits 404. The diameter of hole 403 is smaller than the outside diameter of the cylindrical exterior surface of sealing well 74 that is disposed inside the cell. Thus, when disk 401 is forced axially onto the exterior surface of sealing well 74, the tabs in disk 401 will be forced to deflect slightly open. The deformed interference fit created by the spring tabs 406 of disk 401 thereafter firmly secures disk 401 to cover 40 in a tight compressive manner, thereby ensuring electrical connection of cover 40 with spring strip 28.
Collector assembly 420 is formed from a single piece of material, that is shown in FIG. 4C, with disk 401 being integrally joined to first forming member 465 and second forming member 466. Members 465 and 466 are appropriately bent and joined in region 402 to form the spring legs 32 and 34 of spring strip 28.
To fabricate the cell illustrated in FIGS. 1 through 3, cell cover 40 is drawn so as to have the shape shown in FIGS. 1 and 3. The fabrication sequence is illustrated by FIGS. 5A-5F. Specifically, a stainless steel strip, e.g., of 0.012 inch thick 304L stainless steel, having a smooth surface finish is subjected to a blanking operation, which cuts out a flat disc of a size sufficient so that cover 40 can be drawn from it. The disc is then drawn into a cup shape, as shown in FIG. 5A, and cover flange 90 is partially formed by reverse bending the periphery of the partially formed cover, as shown in FIG. 5B.
Vent liner containment section 60 and annular cap section 80 are next formed in the partially formed cover by a drawing operation. To prevent cracking during drawing, it is preferred that this drawing operation be performed in a number of steps, each successively drawing cover 40 closer to its final form. Subsequent to the step that yields the cover shape shown in FIG. 5B, nine steps are used to draw cover 40 to its final form. Specifically, after forming the cover shape shown in FIG. 5B, the cover is drawn to form a bowl section 503, as shown in FIG. 5C, from which vent liner containment section 70 will be formed. Five successive drawing steps are next performed to successively narrow the bowl section 503 and to yield the cover shape shown in FIG. 5D. The next drawing step starts to form annular cap section 80 and yields the cover shape shown in FIG. 5E. Two further drawing steps yield the final configuration of cover 80, as shown in FIG. 5F. Cover orifice 60 is then formed in a punching operation. Alternatively the containment section 70 may be formed first in the drawing operations.
The foregoing drawing operations will affect somewhat the smooth surface finish of the steel. However, the finish will remain sufficiently smooth such that subsequent insertion of vent liner 29 into sealing well 74 can be performed in a way that yields intimate contact between them, as is discussed below.
Cylindrical vent liner 29 preferably has an outside diameter slightly larger than the inside diameter of cylindrical sealing well 74 so that vent liner 29 can be press-fitted into sealing well 74 to yield an interference fit. In a present embodiment, a vent liner 29 having an outside diameter of 0.135 inch is press-fitted into a sealing well 74 having an inside diameter of 0.125 inch.
Vent liner 29 is inserted into sealing well 74 until the bottom of vent liner 29 abuts support ledge 72. In this way, support ledge 72 provides a positive stop against which vent liner 29 cannot be further inserted, thereby eliminating the need for any flange at the top of the vent liner. In addition, the interference fit causes the outer surface of vent liner 29 to be strongly forced against the inner surface of sealing well 74, which causes intimate contact between those two surfaces, thereby effectively preventing the transport of lithium ions from the inside to the outside of the cell via the interface between vent liner 29 and sealing well 74. Since containment section shoulder 76 is rounded, insertion of liner 29 is made easier, and the potential for scoring the liner during insertion is minimized. It is preferred that the length of vent liner 29 be such that, when inserted in sealing well 74, the upper circular end of vent liner 29 is flush with cover ledge 77.
It is also preferred for oxyhalide cells that sealing well 4 be coated with a sealant prior to insertion of liner 29. Such a sealant more completely ensures the sealing of liner 29 to sealing well 74 in the event of possible imperfections on the surface of liner 29 or sealing well 74. The sealant can be a halocarbon wax, which is a saturated low-molecular weight polymer of chlorotrifluoroethylene, or a fluoroelastomer. Alternatively, since Tefzel® is heat bondable, vent liner 29 when made of this material can be sufficiently heated prior to or after insertion into sealing well 74 and press bonded therein.
After insertion of vent liner 29 into sealing well 74, disk 401 of spring collector assembly 420 is pressed onto the cylindrical outside of sealing well 74 and cover 40 is inserted into its proper location inside annular gasket 52, which is located at the open end of cell container 2. It is preferred that gasket 52 be made of Tefzel® and coated with a sealant of the same type preferably used to coat sealing well 74. At the time cover 40 is inserted into annular gasket 52, container 2 has already been supplied with a cathode collector shell 4, a separator liner 6 and bottom separator 10, a two-member anode 12, and backing sheets 15 and 17. As cover 40 is positioned with respect to gasket 52, the legs 32, 34 of the spring strip 28 are squeezed toqether and forced into the axial opening between the two screen-backed anode members 14 and 20, as shown in FIGS. 1 and 2. The inserted spring strip 28 resiliently biases the two anode members 14 and 20 via backing screens 15 and 17 so as to provide substantially uniform and continuous pressure contact over the inner wall of the anode members.
After inserting cover 40 inside gasket 52, the cell is closed and sealed using conventional closing techniques, so that cell container 2 and cell cover 40 make up a sealed cell housing. A fill head assembly is next pressed against the top of vent liner 29. If the upper circular end of vent liner 29 is flush with cover ledge 77, as is preferred, then the fill head also presses against cover ledge 77. The cell is then filled with cathode-electrolyte.
After the container is filled with cathode-electrolyte, seal member 56 is disposed over vent liner orifice 25 in liner 29, and a ram member is used to force seal member 56 into orifice 25 until further insertion is resisted because of the presence of support ledge 72. In the prior construction, if the seal member were inserted too deeply in the vent liner, higher than desired vent pressures resulted, giving rise to the potential for cell disassembly under conditions of abuse. On the other hand, if the seal member were not inserted to a sufficient depth in the vent liner, then venting could occur during conditions of normal use, thereby causing unnecessary damage to the device using the cell. In the present invention, the placement of seal member 56 is less critical, and support ledge 72 provides a positive stop against which seal member 56 can be pressed, thereby providing easily reproducible vent pressures.
After removal of the ram, a layer of sealant 62 is disposed over seal member 56, vent liner 29 and extended onto cover ledge 77 to produce a fully sealed cell. Suitable sealing materials include halocarbon wax, asphalt, or any other material that is resistant to moisture, has reasonable adhesion to metal and is applied easily. Preferably, the sealant material should be applied in liquid form and then allowed to solidify. The cell is then finished, as by encasing it in a steel jacket and covering cap section 80 with a finishing cover (not shown).
A cell employing the present invention can be made smaller than can a cell using the prior construction. In the prior construction, the vent liner required a flange on its upper edge to prevent the vent liner from dropping into the interior of the cell. The seal member needed to clear this flange before venting could occur; in consequence, the height between the finishing cover and the upper surface of the cover had to be sufficient to accommodate both the diameter of the seal member and the thickness of the flange. In the present invention, however, since the upper circular end of vent liner 29 can be made flush with cover ledge 77, the height between the finishing cover and cover ledge 77 need only accommodate the diameter of seal member 56.
It is to be understood that the improved vent liner and cover construction of this invention could be used in connection with other cells such as, for example, Leclanche dry cells, zinc chloride cells, lithium-MnO 2 cells, lithium-iron sulfide cells, alkaline-MnO 2 cells, nickel-cadmium cells, and lead-acid cells. | An electrochemical cell having a cell housing that contains the active components of the cell; the cell housing having a vent liner containment section that comprises a sealing well having a bottom disposed toward the interior of the cell, an orifice in the sealing well and a support ledge at the bottom of the sealing well; a vent liner having a vent liner orifice disposed within the sealing well so that an end of the vent liner abuts the support ledge, the orifice in the sealing well and the vent liner orifice providing a path from the interior of the cell to the atmosphere; and a seal member force-fitted within the vent liner, wherein the vent liner and the seal member are adapted so that the seal member will be at least partially expelled from the vent orifice at a predetermined internal gas pressure within the cell. | 7 |
TECHNICAL FIELD
[0001] The present invention relates to a parking brake device.
BACKGROUND ART
[0002] For example, a foot-operated parking brake device in which a brake pedal is composed of left and right pedal plates has been proposed (see Patent Document 1).
CITATION LIST
Patent Literature
[0003] {Patent Document 1}
[0004] Japanese Patent Application Publication No. 2011-189907
SUMMARY OF INVENTION
Technical Problem
[0005] However, in the parking brake device described in Patent Document 1, the brake pedal is provided with a ratchet mechanism composed of a ratchet pawl (pawl portion) meshing with a ratchet plate (teeth portion), a support pin, a stopper plate, and the like. Therefore, in order to place the ratchet mechanism to the brake pedal, the brake pedal must be configured with two plates of a left pedal plate and a right pedal plate, and there has been a possibility that the brake pedal becomes heavy.
[0006] An object of the present invention is to provide a parking brake device which can be composed of a lightweight brake pedal.
Solution to Problem
[0007] An invention according to claim 1 is a parking brake device, which is mounted on a vehicle and includes: a brake lever which is rotatable in a predetermined angle range from an initial position with respect to a vehicle body side; a pair of base plates which are fixed to the vehicle body side and rotatably supports the brake lever via a rotating shaft; a teeth portion which is formed with a plurality of continuous teeth and rotates together with the brake lever; a support pin for connecting the pair of base plates to each other; a pawl portion which is swingably supported by the support pin and meshes with the teeth portion; a brake cable which is configured to include an outer cable and an inner cable, in which one end of the outer cable is attached to the base plate via a cable attachment portion, and one end of the inner cable is supported by the brake lever; and a cable guide which is provided to the brake lever and is wound with the inner cable, wherein the teeth portion and the pawl portion are located below the inner cable in a state where the inner cable is wound around the cable guide, and wherein the pawl portion is located between the rotating shaft and the cable attachment portion.
[0008] According to this invention, by placing the support pin and the pawl portion on the base plate, it is not necessary that the brake pedal is composed of a pair of pedal plates as in the prior art. That is, by connecting the pair of base plates to each other via the support pin, and by placing the support pin and the pawl portion between the rotating shaft of the brake lever and a attachment point on the vehicle body side of the base plate, it is possible that the brake pedal is composed of a single brake lever (a piece of plate), thereby reducing the weight of the brake lever.
[0009] Further, since the pair of base plates are connected to each other by the support pin, the support pin contributes to the pair of base plates as a reinforcing member. For example, it is possible to increase rigidity in a case where a force in a twisting direction is applied to the base plate when the brake pedal is operated.
[0010] Further, since the inner cable does not hit the teeth portion and the pawl portion in the state where the inner cable is wound around the cable guide, it is possible to achieve both a guide function for the inner cable by the cable guide and a placement of the pawl portion (part of the ratchet mechanism) on the base plate.
[0011] Furthermore, since the pawl portion is not placed on the brake lever, the cable guide can be independently provided. Therefore, it is possible to reduce the size of the brake lever compared to the prior art, thereby reducing the weight of the brake lever.
[0012] An invention according to claim 2 is a parking brake device, wherein the pair of base plates have projecting portions projecting from the pair of base plates toward both side surfaces of the brake lever or toward both side surfaces of the teeth portion.
[0013] According to this invention, it is possible to prevent the brake lever or the teeth portion from moving in a different direction (direction twisted with respect to the rotating shaft) from a rotational direction around the rotating shaft, thereby improving operability of the brake lever.
[0014] An invention according to claim 3 is a parking brake device, wherein the projecting portion includes a first projecting portion which is disposed on the outer periphery of the rotating shaft in the base plate, and a second projecting portion which is spaced from the first projecting portion and disposed at an end portion of the base plate.
[0015] According to this invention, it is possible to support the teeth portion or the brake lever at two points which are spaced apart from each other. Therefore, it is possible to stably prevent backlash by preventing the brake lever or the teeth portion from being moved in a different direction (direction twisted with respect to the rotating shaft) from the rotational direction around the rotating shaft.
[0016] An invention according to claim 4 is a parking brake device, wherein the rotating shaft is located between the pair of base plates, wherein the teeth portion is rotatably supported on the rotating shaft, and wherein the brake lever is supported by the rotating shaft via the teeth portion.
[0017] However, in the conventional case, when supporting the brake lever by a single plate on the rotating shaft, in order to reduce thickness and weight of the brake lever to be supported by the rotating shaft, a machining that increases a support surface on the rotating shaft by cutting and raising an attachment hole to the rotating shaft by burring or the like has been necessary, so that the brake lever is not inclined or twisted with respect to the rotating shaft. According to the invention of claim 4 , it is possible to reduce machining cost because it is not necessary to perform operations such as burring on the brake lever, while it is possible to reduce the weight of the brake lever because it is not necessary to increase the thickness of the brake lever more than necessary.
[0018] An invention according to claim 5 is a parking brake device, wherein the brake lever has a clearance in a direction perpendicular to an axial direction of the rotating shaft, and is supported on the teeth portion.
[0019] According to this invention, since the brake lever is supported by the rotating shaft via the teeth portion, it is possible to support the brake lever by the rotating shaft even if the brake lever is formed with a thin thickness, thereby reducing the weight of the brake lever.
[0020] An invention according to claim 6 is a parking brake device, wherein the first projecting portions of the pair of base plates clamp only the teeth portion while one of the first projecting portions is inserted through the clearance.
[0021] When two plates are clamped together, there is a possibility that the two plates are moved or twisted to each other, however, according to this invention, it is possible to reliably prevent backlash because only a single teeth portion is clamped.
[0022] An invention according to claim 7 is a parking brake device, wherein a thickness at a portion supported on the rotating shaft of the teeth portion is formed to be greater than a thickness in the vicinity of the rotating shaft of the brake lever.
[0023] According to this invention, since a thickness at the portion supported on the rotating shaft of the teeth portion is formed to be greater than a thickness in the vicinity of the rotating shaft of the brake lever, burring or the like is not necessary for the teeth portion, thereby reducing machining operations or the like.
[0024] An invention according to claim 8 is a parking brake device, wherein the rotating shaft is located between the pair of base plates, wherein the teeth portion is rotatably supported on the rotating shaft, and wherein the brake lever and the teeth portion respectively include shaft holes which are flush with each other and slide with respect to the rotating shaft.
[0025] According to this invention, since both the brake lever and the teeth portion are supported by the rotating shaft, they can be supported with thickness of two members of the brake lever and the teeth portion, thereby supporting the brake lever in a stable manner.
Advantageous Effects of Invention
[0026] According to the present invention, it is possible to provide a parking brake device which can be composed of a lightweight brake pedal.
BRIEF DESCRIPTION OF DRAWINGS
[0027] FIG. 1 is a left side view showing a parking brake device according to an embodiment of the present invention;
[0028] FIG. 2 is a right side view showing the parking brake device according to the embodiment of the present invention;
[0029] FIG. 3 is a left side view of a state of removing a left side base plate of the parking brake device according to the embodiment of the present invention;
[0030] FIG. 4 is a right side view of a state of removing a right side base plate of the parking brake device according to the embodiment of the present invention;
[0031] FIG. 5 is a schematic cross-sectional view taken along a line A-A in FIG. 1 ;
[0032] FIG. 6 is an operation explanatory view of the parking brake device;
[0033] FIG. 7 is a schematic cross-sectional view showing a parking brake device according to a modified example of the embodiment of the present invention;
[0034] FIG. 8 is a perspective cross-sectional view showing a main part of a parking brake device according to another embodiment of the present invention;
[0035] FIG. 9 is a cross-sectional view showing a support structure of a brake pedal in the other embodiment of the present invention; and
[0036] FIG. 10 is a cross-sectional view showing a support structure of a brake pedal in a modified example of the other embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0037] Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 6 . Note that, in the present embodiment, a foot-operated parking brake device 1 which is operated by a driver's foot will be described as an example, however, it may be, for example, a lever-type parking brake device which is provided in an instrument panel of a vehicle and is operated by a driver's hand.
[0038] FIG. 1 is a left side view showing a parking brake device according to the present embodiment, and FIG. 2 is a right side view showing the parking brake device according to the present embodiment. Note that, in FIG. 1 , a front side in a direction perpendicular to a sheet is a left side in a vehicle width direction, and in FIG. 2 , a front side in a direction perpendicular to a sheet is a right side in a vehicle width direction. Further, in FIGS. 1 and 2 ( FIGS. 3 and 4 as well), a dash panel 100 side is a front side of the vehicle. Note that, the dash panel 100 is, for example, located in front of a driver's seat, and is a part constituting a vehicle body, which partitions a vehicle compartment space and a power plant accommodating space (driving source accommodating space) in which an engine, a motor, or the like is mounted.
[0039] As shown in FIGS. 1 and 2 , the parking brake device 1 is disposed at the foot of the driver's seat, and is configured to include a brake pedal 2 (brake lever), a left base plate 3 , a right base plate 4 (sometimes collectively referred to as a pair of base plates 3 , 4 ), a return spring 5 , and the like. Note that, FIGS. 1 and 2 ( FIGS. 3 and 4 as well) show when the brake pedal 2 is in an initial state (when the brake pedal 2 is not depressed, and a braking force is not generated).
[0040] The brake pedal 2 is adapted to be depressed by the driver's foot, and is formed to be elongated from a rear lower side toward a front upper side so as to be substantially W-shaped in a side view by press molding of a single steel plate. That is, the brake pedal 2 in the present embodiment is not a combination of two plates, but is made of a single plate.
[0041] Further, the brake pedal 2 is rotatably supported by the pair of base plates 3 , 4 via a center pin G (rotating shaft), and in the initial state, one end (a lower end) thereof is located at the most rear side, and the other end (an upper end) thereof is located at the most front side (dash panel 100 side). Furthermore, the lower end of the brake pedal 2 is, for example, provided with a rubber pedal pad 2 a.
[0042] The pair of base plates 3 , 4 are, for example, formed by press molding of steel plates, and are disposed on the left and right sides of the brake pedal 2 . Further, as shown in FIG. 1 , the left base plate 3 is formed with a plate portion 3 a and a plate portion 3 b so as to be in a substantial V-shape in a side view. As a reference of the center pin G, the plate portion 3 a extends obliquely upward toward the dash panel 100 (in a direction along the brake pedal 2 ), and the plate portion 3 b extends obliquely downward toward the dash panel 100 (in a direction substantially perpendicular to the brake pedal 2 ) and is formed wider than the plate portion 3 a.
[0043] Further, as shown in FIG. 2 , the right base plate 4 is formed with a plate portion 4 a and a plate portion 4 b so as to be in a substantial V-shape in a side view. As a reference of the center pin G, the plate portion 4 a extends obliquely upward toward the dash panel 100 (in the direction along the brake pedal 2 ), and the plate portion 4 b extends obliquely downward toward the dash panel 100 (in the direction substantially perpendicular to the brake pedal 2 ) and is formed wider than the plate portion 4 a . Note that, the left base plate 3 and the right base plate 4 are configured to have substantially the same shape in a side view.
[0044] Further, as shown in FIG. 1 , the left base plate 3 is fastened to the dash panel 100 via bolts or the like at a front end 3 a 1 of the plate portion 3 a and a front end 3 b 1 of the plate portion 3 b . Further, as shown in FIG. 2 , the right base plate 4 is fastened to the dash panel 100 via bolts or the like at a front end 4 a 1 of the plate portion 4 a and a front end 4 b 1 of the plate portion 4 b . In particular, the front ends 3 a 1 , 3 b 1 , 4 a 1 , 4 b 1 are respectively formed to be bent in a direction along the dash panel 100 , and the bent formed front end portions are fastened to the dash panel 100 via the bolts or the like. Note that, in the present embodiment, points P 1 , P 2 (see FIG. 1 ) and points P 3 , p 4 (see FIG. 2 ), where the front ends 3 a 1 , 3 b 1 , 4 a 1 , 4 b 1 of the pair of base plates 3 , 4 and the dash panel 100 are fastened to each other, correspond to vehicle body side attachment points of the base plates 3 , 4 .
[0045] The return spring 5 is, for example, made of a coil-shaped one, and one end 5 a thereof is hooked to a cable guide 20 to be described later, while the other end 5 b thereof is hooked to a hole (not shown) of a plate portion 3 b 2 (see FIG. 2 ) which is formed integrally with the plate portion 3 b of the left base plate 3 . By elastic restoring force of the return spring 5 , an urging force in a return direction (clockwise direction in FIG. 2 ) is always applied to the brake pedal 2 .
[0046] FIG. 3 is a left side view of a state of removing a left side base plate of the parking brake device according to the present embodiment, and FIG. 4 is a right side view of a state of removing a right side base plate of the parking brake device according to the present embodiment.
[0047] As shown in FIG. 3 , in the brake pedal 2 , a concentric circular through-hole 2 b with a diameter greater than a diameter of the center pin G is formed around the center pin G. Further, in the brake pedal 2 , a connecting hole 2 c having a diameter smaller than that of the through-hole 2 b is formed on one side (the pedal pad 2 a side) with respect to the through-hole 2 b , and a connecting hole 2 d is formed on the other side with respect to the through-hole 2 b . Note that, FIG. 3 is a state of removing the left base plate 3 , and shows a state in which an annular clearance CL is formed between the through-hole 2 b and a periphery of the center pin G of the brake pedal 2 , and further shows a state in which connecting pins 6 , 6 to be described later are inserted into the connecting holes 2 c , 2 d.
[0048] Further, an upper front end of the brake pedal 2 is formed with an arcuate contact portion 2 e which is in contact with a peripheral surface of a regulating pin 9 firmly fixed to the right base plate 4 . The regulating pin 9 has a function of stopping the brake pedal 2 at an initial position thereof when the brake pedal 2 rotates back in a counterclockwise direction in FIG. 3 by the elastic restoring force of the return spring 5 , and is firmly fixed between the plate portion 4 a of the right base plate 4 shown in FIG. 3 and the plate portion 3 a (see FIG. 4 ) of the left base plate 3 shown in FIG. 4 . Note that, the regulating pin 9 is located in the vicinity of the dash panel 100 (the vicinity of the points P 1 , P 3 ), and is adapted to come into contact with the brake pedal 2 at a position away from the center pin G of the brake pedal 2 .
[0049] Further, as shown in FIG. 3 , the parking brake device 1 includes a brake cable 10 , a cable guide 20 , and a ratchet mechanism 30 .
[0050] The brake cable 10 is configured to include a cable attachment portion 11 , an outer cable 12 , and an inner cable 13 .
[0051] The cable attachment portion 11 is one to fix an end portion (one end) of the outer cable 12 , and is, for example, fixed between the plate portion 3 b (see FIG. 1 ) of the left base plate 3 and the plate portion 4 b of the right base plate 4 by means of screws (not shown). Further, the cable attachment portion 11 is substantially T-shaped in a side view, and an opening 11 a through which the inner cable 13 is pulled out is disposed to face substantially upward.
[0052] For example, the outer cable 12 extends to the vicinity of brake devices (not shown, drum brakes or disc brakes) of left and right rear wheels, while enclosing the inner cable 13 .
[0053] An end portion (One end) of the inner cable 13 is pivotally connected to an upper end of the brake pedal 2 via a pivot pin 13 p . Note that, the upper end portion of the brake pedal 2 is, for example, partially folded to form plate-like portions facing each other, and the pivot pin 13 p is inserted into a hole 2 f (see FIG. 3 ) and a hole 2 g (see FIG. 4 ) which are formed in the plate-like facing portions, so as to connectively support the inner cable 13 in a rotatable manner.
[0054] Note that, although not shown, the other end of the inner cable 13 is connected to the brake devices (not shown) of the left and right rear wheels via an equalizer mechanism. By depressing the brake pedal 2 to pull the inner cable 13 , the brake devices (not shown) are adapted to exert braking forces in a different system from a foot brake system.
[0055] The brake guide 20 is adapted to vary a lever ratio to be described later, and is fixed to a left side surface 2 LF of the brake pedal 2 . The cable guide 20 includes a substantially arcuate winding portion 21 which is wound with the inner cable 13 when the brake pedal 2 is depressed, and a guide portion 22 for guiding the inner cable 13 to the winding portion 21 .
[0056] Note that, the cable guide 20 is, for example, composed of two plate members, to be formed by bonding both ends of the two plate members to each other, and is formed with a space (not shown) for guiding the inner cable 13 in a front-rear direction between the both ends thereof. Further, the cable guide 20 is configured such that the inner cable 13 is arcuately wound along a line indicated by a code L in FIG. 3 .
[0057] The winding portion 21 shows substantially fan shape in a side view, and is disposed so as to be along a circumferential direction of the through-hole 2 b in the vicinity in front of the through-hole 2 b . The guide portion 22 extends obliquely upward and forward so as to be away from the center pin G at an upper end of an outer peripheral edge of the winding portion 21 , and is configured such that a tip end thereof is located on the dash panel 100 side relative to the inner cable 13 at the initial position of the brake pedal 2 . Further, the one end 5 a of the return spring 5 described above is hooked to a tip end 22 a of the guide portion 22 .
[0058] In this manner, in the parking brake device 1 according to the present embodiment, by depressing the brake pedal 2 , the inner cable 13 is moved rearward along the guide portion 22 , to be in contact with the winding portion 21 . With this configuration, the ratio (lever ratio) varies between before and after the inner cable 13 comes into contact with the winding portion 21 (variable ratio). Note that, that the ratio varies means that a relationship between a pulling amount of the inner cable 13 and a stroke amount during depression of the brake pedal 2 varies.
[0059] As shown in FIGS. 3 and 4 , the ratchet mechanism 30 has a function of holding the brake pedal 2 at the angle when depressed by the driver, and is composed of a ratchet plate 31 (teeth portion), a ratchet pawl 32 (pawl portion), a stopper plate 33 , a support pin 34 , a turnover spring 35 , and the like.
[0060] As shown in FIG. 4 , the ratchet plate 31 is fixed to a right side surface 2 LR of the brake pedal 2 . That is, the ratchet plate 31 includes a fixed portion 31 a fixed to the brake pedal 2 , and a ratchet teeth 31 f formed with a plurality of continuous teeth meshing with the ratchet pawl 32 . The ratchet teeth 31 f are located below the center pin G in the vertical direction (up-down direction).
[0061] The fixed portion 31 a is formed with a shaft hole 31 b through which the center pin G is inserted, and connecting holes 31 c , 31 d are formed at positions corresponding to the connecting holes 2 c , 2 d (see FIG. 3 ). Further, the fixed portion 31 a has an extending portion 31 e having a substantial U-shape in a side view, and a lower end outer edge portion of the extending portion 31 e is formed with the ratchet teeth 31 f . The ratchet teeth 31 f of the ratchet plate 31 is formed so as to have an arc shape around the center pin G, and is adapted to rotate with a rotation operation of the brake pedal 2 when the brake pedal 2 is depressed.
[0062] The ratchet pawl 32 is swingably supported between the pair of base plates 3 , 4 via the support pin 34 . That is, the ratchet pawl 32 is formed with a long-hole 32 a , and by inserting the support pin 34 with a play into the long-hole 32 a , the ratchet pawl 32 is swingably supported by the support pin 34 . Further, the ratchet pawl 32 has a pawl 32 b (see FIG. 3 ) meshing with the ratchet teeth 31 f of the ratchet plate 31 . Furthermore, the ratchet pawl 32 is located between (substantially between) the cable attachment portion 11 and the ratchet plate 31 in the vertical direction (up-down direction).
[0063] The stopper plate 33 is fixed to the ratchet pawl 32 , and is configured to swing together with the ratchet pawl 32 , so that a swing fulcrum of the ratchet pawl 32 is changed in response to a depression state of the brake pedal 2 .
[0064] The support pin 34 is supported by shaft holes (not shown) formed in the pair of base plates 3 , 4 , and thus connects between the pair of base plates 3 , 4 .
[0065] The turnover spring 35 is, for example, hung over both the right base plate 4 and the ratchet pawl 32 .
[0066] The ratchet pawl 32 and the support pin 34 are disposed between the center pin G of the brake pedal 2 and the attachment points P 1 , P 2 (P 3 , P 4 ) to the dash panel 100 of the base plate 3 ( 4 ). In other words, the ratchet pawl 32 and the support pin 34 are located between the center pin G and the attachment points P 1 , P 2 (P 3 , P 4 ) in the front-rear direction of the vehicle.
[0067] When the driver depresses the brake pedal 2 during stopping (parking) of the vehicle, the ratchet pawl 32 urged by the turnover spring 35 is engaged with the ratchet teeth 31 f of the ratchet plate 31 , so that return of the brake pedal 2 is prevented. At this time, the stopper plate 33 is moved downward with respect to the support pin 34 , so that the turnover spring 35 is inverted to urge the ratchet pawl 32 in an opening direction. On the other hand, when the driver depresses the brake pedal 2 again during starting of the vehicle, the ratchet pawl 32 urged by the turnover spring 35 is separated from the ratchet plate 31 , and when the driver releases the depression force, the brake pedal 2 urged by the return spring 5 is rotated toward the initial state. When the brake pedal 2 is returned to the initial state, the stopper plate 33 (i.e., the ratchet pawl 32 ) is rotated by a collision with a projecting piece formed on the brake pedal 2 , and the turnover spring 35 is inverted again, to urge the ratchet pawl 32 in the engagement direction (for example, see Japanese Patent Application Publication 2011-189907).
[0068] FIG. 5 is a schematic cross-sectional view taken along a line A-A in FIG. 1 . Note that, the cross-sectional view shown in FIG. 5 shows a simplified cross-sectional shape of the brake pedal 2 and the pair of base plates 3 , 4 .
[0069] As shown in FIG. 5 , the connecting holes 2 c , 2 d of the brake pedal 2 and the connecting holes 31 c , 31 d of the ratchet plate 31 are respectively connected to each other via the connecting pins 6 . Further, the center pin G is slidably inserted into the shaft hole 31 b formed in the ratchet plate 31 , and the center pin G is supported by the pair of base plates 3 , 4 . Note that, the center pin G is inserted into a shaft hole 3 g formed in the left base plate 3 and a shaft hole 4 g formed in the right base plate 4 , and is firmly fixed to the pair of the base plates 3 , 4 at both ends of the center pin G.
[0070] In this manner, the parking brake device 1 according to the present embodiment is configured such that the brake pedal 2 is not directly rotatably supported by the pair of the base plates 3 , 4 , but is rotatably supported by the center pin G via the ratchet plate 31 .
[0071] As a result, by increasing a thickness t 1 of a portion supported on the center pin G of the ratchet plate 31 to be greater than a thickness t 2 in the vicinity of the center pin G of the brake pedal 2 (t 1 >t 2 ), burring or the like is not necessary for the ratchet plate 31 , thereby reducing machining operations or the like.
[0072] In addition, although not shown, the brake pedal 2 may be provided with a parking brake sensor for detecting that the brake pedal 2 is depressed. The parking brake sensor can, for example, turn on a parking indicator (lamp) provided in meters and gauges, by depressing the brake pedal 2 to turn on the sensor (switch).
[0073] Next, an operation of the parking brake device 1 according to the present embodiment will be described with reference to FIG. 6 . Note that, FIG. 6 shows a state where the left base plate 3 is removed, and a state after rotation of the ratchet mechanism 30 of the brake pedal 2 and a state after rotation of the return spring 5 are not shown.
[0074] When the driver depresses the brake pedal 2 from the initial state after parking a car (vehicle), as shown in FIG. 6 , the brake pedal 2 is rotated in the clockwise direction around the center pin G, and the pivot pin 13 p is rotated, and thus the inner cable 13 is swung rearward while being pulled out from the outer cable 12 . In this case, an angle (a crossing angle) θ formed by a line L 1 connecting the center pin G and the pivot pin 13 p , and a line connecting the center pin G and one end 12 s of the outer cable 12 is an obtuse angle at the initial stage, and is increased in response to depression of the brake pedal 2 , and thus a lever ratio (a ratio of a depression amount of the brake pedal 2 to a pulled-out amount of the inner cable 13 ) is gradually increased.
[0075] Then, when the driver further depresses the brake pedal 2 , as shown by two-dot chain lines in FIG. 6 , the inner cable 13 comes into contact with the winding portion 21 of the cable guide 20 , and is then wound around the winding portion 21 of the cable guide 20 . In the present embodiment, the lever ratio increases until the inner cable 13 comes into contact with the winding portion 21 of the cable guide 20 , but starts to gradually decrease from the time (winding start point P) when the inner cable 13 starts to be wound around the winding portion 21 of the cable guide 20 .
[0076] In this manner, in an early stage of depression of the brake pedal 2 , operability is improved because the pulled-out amount of the inner cable 13 is increased. Further, in a middle stage of depression of the brake pedal 2 , a sufficient parking brake force is ensured because the pulled-out amount of the inner cable 13 is decreased (that is, because the tensile force is increased). Then, in a last stage of depression of the brake pedal 2 , reliable parking brake is achieved because the pulled-out amount of the inner cable 13 is increased (because increase of the lever ratio is suppressed) as compared to the middle stage of depression.
[0077] As described above, the parking brake device 1 according to the present embodiment includes: the brake pedal 2 which is rotatable in a predetermined angle range from an initial position with respect to the dash panel 100 ; the pair of base plates 3 , 4 which are fixed to the dash panel 100 and rotatably supports the brake pedal 2 ; the ratchet plate 31 which is formed with the ratchet teeth 31 f and rotates together with the brake pedal 2 ; the support pin 34 for connecting the pair of base plates 3 , 4 to each other; and the ratchet pawl 32 (pawl 32 b ) which is swingably supported by the support pin 34 and meshes with the ratchet plate 31 (ratchet teeth 310 , wherein the support pin 34 and the ratchet pawl 32 are arranged to be located between the center pin G (rotating shaft) of the brake pedal 2 and the attachment points P 1 , P 2 , P 3 , P 4 (vehicle body side attachment points) to the dash panel 100 of the pair of base plates 3 , 4 .
[0078] In this manner, by placing the support pin 34 and the ratchet pawl 32 on the pair of base plates 3 , 4 , it is not necessary to provide a pair of pedal plates as in the prior art. That is, by connecting the pair of base plates 3 , 4 to each other via the support pin 34 , and by placing the support pin 34 and the ratchet pawl 32 between the center pin G of the brake pedal 2 and the attachment points P 1 , P 2 , P 3 , P 4 to the dash panel 100 of the pair of base plates 3 , 4 in the front-rear direction of the vehicle, it is possible to employ the brake pedal 2 which is formed by press molding of a single steel plate, thereby reducing the weight of the brake pedal 2 .
[0079] Further, since the ratchet pawl 32 is disposed not on the brake pedal 2 but on the base plate 3 ( 4 ), it is possible to reduce the weight of the brake pedal 2 also in this respect. In this manner, it is possible to reduce the weight of the brake pedal 2 in a state where a variable ratio mechanism can be used.
[0080] Further, by connecting the pair of base plates 3 , 4 to each other via the support pins 34 , the support pin 34 contributes to the pair of base plates 3 , 4 as a reinforcing member, and it is possible to increase rigidity in a case where a force in a twisting direction is applied to the pair of base plates 3 , 4 during depression of the brake pedal 2 .
[0081] Further, the parking brake device 1 according to the present embodiment includes: the brake cable 10 , in which one end 12 s (see FIG. 6 ) of the outer cable 12 is attached to the pair of base plates 3 , 4 via the cable attachment portion 11 , and one end of the inner cable 13 is supported by the brake pedal 2 ; and the cable guide 20 which is provided to the brake pedal 2 and is wound with the inner cable 13 , wherein the ratchet plate 31 and the ratchet pawl 32 are located below the inner cable 13 in a state where the inner cable 13 is wound around the cable guide 20 (winding portion 21 ), and wherein the ratchet pawl 32 is located between the center pin G of the brake pedal 2 and the cable attachment portion 11 in the front-rear direction of the vehicle. Note that, to be located below the inner cable 13 means that when the inner cable 13 is wound around the cable guide 20 , the ratchet plate 31 and the ratchet pawl 32 are located below a portion wound around the cable guide 20 of the inner cable 13 in the vertical direction (up-down direction).
[0082] As a result, since the inner cable 13 does not contact the ratchet plate 31 and the ratchet pawl 32 even if the inner cable 13 is wound around the cable guide 20 , it is possible to achieve both a guide function for the inner cable 13 by the cable guide 20 and a placement of the ratchet pawl 32 on the pair of base plates 3 , 4 .
[0083] Further, since the ratchet pawl 32 is not placed on the brake pedal 2 , the cable guide 20 can be provided independently, and thus it is possible to reduce the size of the brake pedal 2 than the prior art, thereby reducing the weight of the brake pedal 2 .
[0084] Meanwhile, in a case where the brake pedal 2 made of a single plate is supported by the center pin G, when reducing the plate thickness of the brake pedal 2 to reduce the weight thereof, there may occur a problem that the brake pedal 2 is inclined or twisted with respect to the center pin G (rotating shaft) when the brake pedal 2 is supported by the center pin G. In order to prevent such a problem, a machining that increases a support surface on the center pin G by cutting and raising an attachment hole to the center pin G by burring or the like has been necessary.
[0085] Therefore, in the present embodiment, the center pin G is placed between the pair of base plates 3 , 4 , and the ratchet plate 31 is rotatably supported on the center pin G, and further the brake pedal 2 is supported by the center pin G via the ratchet plate 31 , and thus it is possible to reduce machining cost because it is not necessary to perform operations such as burring on the brake pedal 2 , and further it is possible to reduce the weight of the brake pedal 2 because it is not necessary to increase the thickness of the brake pedal 2 more than necessary.
[0086] Further, in the present embodiment, since the brake pedal 2 is supported by the ratchet plate 31 by forming the clearance CL in the brake pedal 2 in a direction (radial direction) perpendicular to an axial direction of the center pin G, the brake pedal 2 is supported by the center pin G via the ratchet plate 31 , and thus it is possible to support the brake pedal 2 by the center pin G even if the brake pedal 2 is constructed with a thin wall thickness, thereby reducing the weight of the brake pedal 2 .
[0087] Meanwhile, when both the brake pedal 2 and the ratchet plate 31 are configured to be supported on the center pin G, accuracy of both the shaft hole formed in the brake pedal 2 and the shaft hole 31 b of the ratchet plate 31 is required, however, since only the ratchet plate 31 is supported on the center pin G, the accuracy is not required.
[0088] Further, in the present embodiment, by forming the thickness t 1 (see FIG. 5 ) at the portion supported on the center pin G of the ratchet plate 31 to be greater than the thickness t 2 (see FIG. 5 ) in the vicinity of the center pin G of the brake pedal 2 , burring or the like is not necessary for the ratchet plate 31 , thereby reducing machining operations or the like.
Modified Example
[0089] FIG. 7 is a schematic cross-sectional view showing a parking brake device according to a modified example of the present embodiment. Note that, as with FIG. 5 , FIG. 7 also shows a simplified cross-sectional shape of the brake pedal 2 and the pair of base plates 3 , 4 .
[0090] As shown in FIG. 7 , the brake pedal 2 is formed with a shaft hole 2 s to be pivotally supported on the center pin G. The ratchet plate 31 is formed with the shaft hole 31 b to be pivotally supported on the center pin G. Further, the shaft hole 2 s and the shaft hole 31 b respectively slide with respect to the center pin G and are flush with each other, and it is configured such that both the brake pedal 2 and the ratchet plate 31 are supported on the center pin G.
[0091] As a result, since both the brake pedal 2 and the ratchet plate 31 are supported on the center pin G, it is possible to support the brake pedal 2 in a stable manner by two thicknesses of the brake pedal 2 and the ratchet plate 31 , thereby stably supporting the brake pedal 2 .
Another Embodiment
[0092] FIG. 8 is a perspective cross-sectional view showing a main part of a parking brake device according to another embodiment, and FIG. 9 is a cross-sectional view showing a support structure of a brake pedal in the other embodiment. Note that, FIG. 8 shows the perspective cross-sectional view when the pair of base plates 3 , 4 are cut in a straight line so as to pass through the connecting pin 6 on the pedal pad 2 a side of the brake pedal 2 and the center pin G (rotating shaft) in FIG. 4 . Further, FIG. 8 shows a configuration in which the brake pedal 2 is supported by the center pin G via the ratchet plate 31 .
[0093] As shown in FIG. 8 , the base plate 3 is formed with a first projecting portion 3 c projecting toward a side surface 31 g of the ratchet plate 31 at the outer periphery of the center pin G. Similarly, the base plate 4 is formed with a first projecting portion 4 c projecting toward a side surface 31 h of the ratchet plate 31 at the outer periphery of the center pin G. The first projecting portions 3 c , 4 c are formed in a concave shape so as to show a substantially truncated conical shape which is reduced in diameter toward the side surfaces 31 g , 31 h.
[0094] Further, the base plate 3 is formed with a second projecting portion 3 e projecting toward a side surface 2 h of the brake pedal 2 at an end portion 3 d of the base plate 3 spaced apart from the first projecting portion 3 c . Similarly, the base plate 4 is formed with a second projecting portion 4 e projecting toward a side surface 2 i of the brake pedal 2 at an end portion 4 d of the base plate 4 spaced apart from the first projecting portion 4 c.
[0095] Further, as shown in FIG. 9 , the first projecting portion 3 c is configured such that a tip portion 3 c 1 thereof has a diameter which is inserted into the clearance CL formed in the brake pedal 2 . Note that, the clearance CL has, for example, a circular shape as shown in FIG. 3 . Then, the ratchet plate 31 is configured to be clamped between the first projecting portion 3 c and the first projecting portion 4 c.
[0096] In this manner, by providing the first projecting portions 3 c , 4 c and the second projecting portions 3 e , 4 e (see FIG. 8 ), it is possible to prevent the ratchet plate 31 from being inclined (moved) in a different direction from the rotational direction around the center pin G, that is, in a direction twisted with respect to the center pin G, thereby improving the operability of the brake pedal 2 .
[0097] Further, by providing the first projecting portions 3 c , 4 c and the second projecting portions 3 e , 4 e (see FIG. 8 ), it is possible to support the ratchet plate 31 and the brake pedal 2 connected to the ratchet plate 31 at two points which are spaced apart from each other, thereby stably preventing backlash by preventing the brake lever 2 and the ratchet plate 31 from being inclined (moved) in the different direction from the rotational direction around the center pin G, that is, in the direction twisted with respect to the center pin G.
[0098] Meanwhile, when the two plates (brake pedal 2 , ratchet plate 31 ) are clamped by the first projecting portions 3 c , 4 c , there is a possibility that the two plates are moved or twisted to each other. Therefore, by clamping only the ratchet plate 31 between the first projecting portion 3 c and the first projecting portion 4 c while the first projecting portion 3 c is inserted into the clearance CL (see FIG. 9 ), it is possible to reliably prevent backlash of the brake pedal 2 .
[0099] Note that, in the embodiment shown in FIG. 8 , a case in which the first projecting portions 3 c , 4 c are formed in a concave shape at an entire outer periphery (peripheral edge portion) of the center pin G including the center pin G has been described as an example, however, it is not limited thereto, but may be configured such that annular first projecting portions are formed on only the outer periphery of the center pin G.
[0100] Further, in the embodiment shown in FIGS. 8 and 9 , a configuration in which the first projecting portion 3 c and the first projecting portion 4 c clamp only the ratchet plate 31 has been described as an example, however it is not limited to such a configuration. For example, as a modified example of the other embodiment, as shown in FIG. 10 , it may be configured such that without providing the clearance CL in the brake pedal 2 , on the outer periphery of the center pin G, the side surface 2 i of the brake pedal 2 and the side surface 31 g of the ratchet plate 31 are coupled so as to be in surface contact with each other, while the first projecting portion 3 c is in surface contact with the side surface 2 h of the brake pedal 2 , and the first projecting portion 4 c is in surface contact with the side surface 31 h of the ratchet plate 31 , and thus both the brake pedal 2 and the ratchet plate 31 are clamped by the first projecting portions 3 , 4 .
[0101] The present invention is not limited to the embodiments (including the modified examples). For example, in the present embodiment, a configuration in which the cable attachment portion 11 is fixed to the base plates 3 , 4 has been described as an example, however, it is not limited thereto, but may be configured such that the cable attachment portion 11 is fixed to the dash panel 100 .
[0102] Further, the shape of the clearance CL has been circular, however, it is not limited to such a shape, but may be appropriately changed to be triangular, rectangular, or the like.
REFERENCE SIGNS LIST
[0000]
1 : parking brake device
2 : brake pedal (brake lever)
3 : left base plate (base plate)
3 c : first projecting portion
3 d : end portion
3 e : second projecting portion
4 : right base plate (base plate)
4 c : first projecting portion
4 d : end portion
4 e : second projecting portion
5 : return spring
6 : connecting pin
9 : regulating pin
10 : brake cable
11 : cable attachment portion
12 : outer cable
13 : inner cable
13 p : pivot pin
20 : cable guide
21 : winding portion
22 : guide portion
30 : ratchet mechanism
31 : ratchet plate (teeth portion)
32 : ratchet pawl (pawl portion)
33 : stopper plate
34 : support pin
35 : turnover spring
100 : dash panel (vehicle body)
CL: clearance
G: center pin (rotating shaft)
P 1 , P 2 , P 3 , P 4 : attachment point (vehicle body side attachment point) | A parking brake device comprises: a brake pedal which is capable of pivoting from an initial position in relation to a dash panel in a determined angle range; a pair of base plates which are fixed to the dash panel, and which sandwich and pivotally support the brake pedal; a ratchet plate in which ratchet teeth are continuously formed, and which pivots together with the brake pedal; a support pin which couples the pair of base plates; and a ratchet pawl which is supported by the support pin in a manner so as to be capable of oscillation, and which meshes with the ratchet plate. The support pin and the ratchet pawl are disposed between attachment points at the dash panel side of the base plates and a center pin of the brake pedal. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to the field of television program ratings measurement and more particularly to apparatus for identifying the viewing audience watching TV programs and commercials.
2. Brief Description of the Prior Art
Conventional automatic television ratings monitors include meters to record which channel a TV set is tuned to and the time of day it is so tuned. At a later time, the contents of the log are transmitted to a central computer via telephone lines where local and national program ratings are computed. Conventional meters cannot usually record the composition of the audience actually watching a particular program and cannot discern whether anyone is watching the program or commercials even though the TV set is on and tuned to a particular channel. For this reason, there is a need for apparatus capable of passive, automatic monitoring of the actual viewing audience.
Various meters for automatic monitoring of the viewing audience, otherwise known as "people meters," have been developed by such companies as Arbitron, Nielsen, Audits of Great Britain, Burke, Market index of Finland, and possibly others. Each of these devices requires the active participation of the viewers, and that the viewers must operate push buttons in response to "prompter" signals or when he leaves or returns to watching the TV set. The arrangements for button pushing vary, as do the "prompts" which automatically appear with some of the devices to remind the viewers to push their buttons. However, none of the "prompter" or push button arrangements have been altogether satisfying in audience measuring systems.
SUMMARY OF THE INVENTION
The present invention provides a television receiver having one or more headphones in wireless communication therewith. Each headphone includes position sensor means to detect the placement of the headphones on a wearer's head, receiver means responsive to said sensor means for receiving the wirelessly transmitted audio portion of the program and providing it to the wearer, and identification means responsive to the sensor means for transmitting a signal representative of each headphone. Monitor means connected to the television receiver includes storage means for storing activity status of the headphones, together with clock means for recording times of such activities.
According to one form of the invention, each headphone transmits its signal using unique optical filters and the monitor discriminates among the various headphones by corresponding filters. Another variation includes transmission of a timing signal to the headphones whereby each headphone begins a unique delay to the time when it responds with its own signal.
Another feature of the invention includes spare or guest headphone identifying means by which a family member with a malfunctioning headphone or a guest may log information concerning himself into a store and have a code for a spare headphone wirelessly transmitted to a spare headphone to activate it. The spare remains activated until the sensor indicates the spare has been removed from the head of the viewer.
In another form of the invention, the wireless communications means includes means to poll the headphones using a headphone unique ID signal. A headphone addressed by the poll responds with an acknowledge signal. Guest and spare headphones may be included in the poll list by the viewer using pushbuttons mounted on the monitor to identify himself and the headphone he intends to use.
Another feature includes voice means in the headphone to identify the headphone to the viewer when he puts on the headphone so that the viewer does not accidentally use the wrong headphone.
Non audio signals transmitted to the headphones are preferably multiplexed with the radiated audio signal.
The invention is intended to operate in conjunction with equipment that monitors the ON/OFF status of the TV set and the channel to which the set is tuned from time to time.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a passive viewer meter according to the presently preferred embodiment of the present invention.
FIG. 2 is a schematic diagram of the monitor of a passive viewer meter according to a modification of the present invention.
FIG. 3 is a partial schematic diagram of a headphone for use with the monitor shown in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a passive viewer meter in accordance with the presently preferred embodiment of the present invention. The system includes TV set 10 being viewed; converter 20 to transmit the audio portion of the television program; monitor 30; and at least one headphone 40 adapted to receive and demodulate the transmitted audio portion of the program and present it to the headphone's speakers.
TV set 10 typically comprises a tuner 12 for tuning to one of a set of frequencies either in the VHF or UHF ranges. The tuner's output comprises separable audio and video signals. The video signal is input to a video monitor 14 television screen. The audio signal is demodulated at 16, amplified at 17 and provided to drive speakers 19 through a volume control 18. Some TV receivers include headphone jacks 21 and audio outputs 23. In either case, these outputs would be connected to the audio amplifier 17. Also, some receivers are capable of receiving stereo broadcast signals, in which case there will be multiple audio channels.
In accordance with the present invention, speakers 19 are disconnected from volume control 18, and headphone jacks 21 are disconnected from the audio amplifier 17. Converter 20 is connected to audio output 23, or to amplifier 17 if audio output 23 is not present.
Converter 20 includes a carrier signal generator 22 which generates a carrier signal typically in the range of 40 khz or more for infrared transmission system and a modulator 24 for modulating the carrier with the audio from the TV set. The output of the modulator is provided to an infrared radiating LED 26 which transmits the audio modulated carrier at infrared frequencies as shown at 27. In a typical home environment, a plurality of such diodes are employed, directed in multiple directions so the radiated information will reach the infrared detector on the headphone(s) at a good power level regardless of the orientation of the viewer's head vis-a-vis the TV set.
While the amplitude modulation is shown here and throughout this description, it is understood that other forms of modulation and/or encoding will work equally as well and are deemed within the scope of the present invention. Other forms of modulation include frequency, pulse code and digital, either of the form having a self-clocking code or of the form having a transmitted carrier.
Headphone 40 includes a rechargeable battery 42 having a plug 41 for recharging the headphone's battery when the headphone is not in use. A rack (not shown) may be provided to house the headphones, the rack including a plurality of plugs for recharging the headphone's batteries when not in use.
The output of battery 42 is connected through normally open switch 44 to the other operable devices of the headphone. Switch 44 is closed when the on-head position sensor (detector) 50 determines that the headphone is positioned on the head of a viewer. When the switch 44 is closed by the on-head sensor 50, power is connected to the reception and amplifying components. This permits the transmitted infrared signal 27 bearing the modulated audio signal to be received by an infrared detector diode 46 and demodulated by demodulator 48 under the influence of oscillator 47, matched to the carrier frequency provided by oscillator 22, the output of which is input to a stereo decoder 49 and volume controls 52. Preferably, the volume controls are manually operated from controls (not shown) mounted on the headphone. The output from the volume controls are connected to the headphone's speakers 54.
On-head sensor 50 comprises any suitable device for sensing the position of the headphones on the head of a viewer, such as a differential heat sensor for sensing the body heat of the wearer, or microswitches mounted to the ear pad or head band of the headphone to detect pressure against the user's head. It is preferred the sensor be a low power consuming sensor becasuse it is preferably permanently connected to batteries 41. Carrier signal generator 56 is connected to switch 44 to generate a carrier signal. Code generator 60 provides a modulation signal in the form of a code unique for that headphone unit. The carrier and modulation signals are modulated by modulator 62 and transmitted by LED 64 to monitor 30. The LED preferably transmits signal 65 in the visible range; however, if infrared is used, the carrier must be sufficiently separated in frequency from the carrier of the audio signal infrared signal so as to not cause interference.
Monitor 30 includes a visible or infrared light detector 32 which detects the modulated visible light signal 65 transmitted by the LED 64 and inputs it to a demodulator 34, which demodulates the headphone identification signal from the carrier. The demodulated headphone ID signal is input to code detect circuit 36, which decodes the code. The output of the code detect is provided to store 70, where it is stored, together with the time of day from a time of day clock 39. Channel information is inputted to store 70 from the TV set tuning monitor with which this invention is intended to operate. Optimally, the apparatus of FIG. 1 may be modified by the inclusion of delay circuit 66 between modulator 62 and LED 64, delay 66 being connected to demodulator 48. Also, modulator 24 in converter 20 would be connected to code detect 36 in monitor 30. At preselected intervals (e.g., each 30 seconds) converter 20 transmits a timing signal to all headphones via LED 26 and detector diodes 46. The timing signal is demodulated by demodulator 48 which in turn operates delay circuit 66 to close the connection between modulator 62 and LED 64 after a selected delay and to open the connection shortly thereafter. If each headphone 40 employs a different delay period, each operating headphone will transmit a signal from its LED 64 to detector 32 during a unique time period. The "window" for transmission would be sensed by code detector 36, initiated by modulator 24.
A variation of this optional delay mechanism would include elimination of unique identification codes for the individual headphones and permit identification to be based on the window established by the unique delays.
Another variation would be to employ unique frequencies for carrier communication from LED 64 with a plurality of photocells 32 responsive to individual frequencies for direct input to code detector 36. For example, if each LED 64 emitted a unique color in the visual spectrum, the plurality of photocells with light filters would receive indication only from selected headphones. The several photocells would provide direct input to code detector 36.
If more than one headphone is present for viewers to use, as normally would be the case, the demographic information concerning the wearer of a given headphone (such as age and sex) is recorded in the store 70 and/or code detect 36. In the case of headphones for family members this data could be inputted to store 70 or to the central collection computer at the time of installation of the meter system. In the case of spare and guest headphone, demographic data of the user would have to be recorded along with the headphone ID number at the time viewing commenced. Demographic data can be inputted to store 70 by a keyboard, such as shown in FIG. 2.
Preferably, the spare or guest headphones would not be operable to receive audio unless enabled by the monitor in response to the entry of the demographic data. This requires transmitting a headphone unique ID signal from the monitor to a particular headphone to enable its reception of audio. FIG. 2 illustrates an embodiment for transmitting coded signals to the headphones. The coded signals comprise the aforementioned timing signal or a headphone unique ID signal. As shown in FIG. 2, microprocessor 82 is connected to store 70 and ID modulator 94. Microprocessor 82 receives optional input from keyboard 90, for example, to input demographic data concerning users. A timer may be part of the microprocessor, or be connected to store 70, as in the case of FIG. 1.
The audio signal from the TV set is connected, as before, to modulator 24, which imposes the audio signal on a carrier from oscillator 22. In FIG. 2, however, the output of oscillator 22 is provided to divide-by-three circuit 92 and directly to modulator 94. Modulator 94 modulates the headphone ID signal from microprocessor 82 to the carrier provided by oscillator 22. Thus, the carrier frequency modulating the headphone ID signal is three times that of the carrier modulating the audio. The two modulated carriers are mixed in mixer 96 and are transmitted by LED 26 driven by driver 98.
FIG. 3 illustrates the headphone useful with the apparatus shown in FIG. 2. As in the case of the apparatus shown in FIG. 1, the modulated audio carrier is detected by detector diode 46 and input to demodulator 48 which demodulates the audio for later stereo decoding, amplification and aural transduction as heretofore described. The oscillator 47 is running at three times the carrier frequency of the received audio signal, so divide-by-three circuit 100 is provided to enable demodulation. An additional demodulator 102 demodulates the timing or the headphone unique ID signal transmitted from the monitor at a carrier frequency three times that of the audio carrier. Thus the oscillator 47 is input directly to the second demodulator 102. ID detect circuit 104 compares the received headphone ID code with the unique code for the headphone, and if a match is detected, ID detect circuit 104 sends an ID recognized signal to switch 114, closing it and enabling power to the audio and/or acknowledge circuitry. Switch 114 is held closed by power from the battery through switch 44. Upon opening switch 44 (for example, upon removal of the headphones) switch 114 is also opened.
The circuitry of FIGS. 2 and 3 may also be useful in a polling arrangement wherein the headphones are polled with a headphone unique ID signal. When a headphone receiver recognizes its ID, it responds with an acknowledge signal. New polls are sent after a previous poll has been acknowledged. Thus, the possibility of two headphones trying to transmit simultaneously is eliminated. The microprocessor contains data for each headphone and generates a headphone identification signal for polling the headphones.
The acknowledge circuitry for the polling arrangement would include ID code generator 60, oscillator 56, modulator 62 and LED 64 all shown in FIG. 1. Thus, upon receipt of the poll signal, the headphone acknowledges by transmission of its ID code or an acknowledge code as heretofore described. Guest or spare headphones are included in the poll list in response to the viewer keying in the headphone number when identifying himself. After one or more failures to acknowledge the poll signal, the headphone is removed from the list. If the guest thereafter wishes to recommence viewing, he must identify himself again.
A final feature of the present invention includes a voice synthesizer actuated by the on-head sensor and connected to the headphone speakers for audible identification of the headphone. When the viewer first puts his headphone on, the synthesizer would say "Dad", "Mom", "Red" or the like. | A meter for passively logging the presence of TV viewers including circuitry for disabling the audio of a TV set, a transmitter for wirelessly transmitting the audio to a plurality of headphones, a circuit responsive to the headphones presence upon the head of a viewer for transmitting a headphone ID signal to a monitor, a receiver in the monitor for logging the fact that particular headphones are activated, and a time of day clock for logging the period of time particular headphones are activated. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electronic component having at least two electrode pads on a surface thereof, an assembly comprising such electronic component and metallic soldering elements usually called "solder bumps", and an electronic component unit comprising such electronic component and another electronic component.
2. Description of the Prior Art
In the conventional method of bonding a semiconductor device to a substrate with solder bumps disposed therebetween, as disclosed in U.S. Pat. No. 5,216,278, the bumps are formed on the semiconductor device at predetermined intervals, electrode pads to be soldered are of the same area, and balls for forming the bumps are of the same size. In the conventional method, a semiconductor device having such a junction structure is bonded to a circuit substrate regardless of warpage of the substrate on which electrode pads are also formed, and also regardless of expansion characteristics of the substrate.
FIGS. 8 and 9 show an example of electronic component units comprising a semiconductor package and a circuit substrate which are connected by the above conventional method,
In these drawings, a semiconductor element 1 is mounted on a base 3 and electrically connected to top electrodes 5a of the base 3 by wires 4. The top electrodes 5a of the base 3 are respectively electrically connected to bottom electrodes 5b. The semiconductor element 1, the wires 4 and the base 3 are sealed with a resin 5. Insulating resist 2 is coated on the lower side of the base 3. The surfaces of the lower surface electrodes 5b of the base 3 have portions without the resist 2 which respectively form electrode pads 6. Solder balls 8 are respectively adhered to the pads 6.
On the other hand, resist 2a is coated on the surface of a substrate 9, and the surfaces of electrodes 10 in the substrate 9 have portions without the resist 2a, which respectively form electrode pads 7. The semiconductor package is mounted on the substrate 9 by melting the solder balls 8 by heat and bonding the balls to the pads 7.
A structure electrically connecting a semiconductor package to a circuit substrate via solder bumps exhibits excellent high-speed electrical processing because the wiring length is decreased by an amount corresponding to the lead length and, thus, conforms to a multi-pin structure and the use of multiple pins because many bumps can be formed, as compared with the connection to a circuit substrate through leads. In this bump connection structure, the bump arrangement area is decreased and the packaging density of the package is increased as the diameter of each solder bump is decreased. The suitable size of each bump, therefore, is considered to be 500 to 700 μm. However, a decrease in size of the bumps causes an increase in cost due to the need for advanced bonding technology, and cause a significant decrease in the strength reliability of the bumps. The problem with respect to the reliability is considered particularly significant partly because the difference in thermal expansion between a substrate on which a chip is mounted and a circuit substrate is accommodated by the solder bumps having a low strength. This is also because warpage invariably remains in the substrate, and the warped substrate is bonded to the circuit substrate, so that tensile loads are apt to be applied to the bumps.
SUMMARY OF THE INVENTION
It is an object of the present invention to solve the above problems of the prior art and to provide a bump connection structure with high reliability.
According to a first feature of the present invention, there is provided an electronic component unit comprising:
a first electronic component having an internal electric circuit therein;
a second electronic component having an internal electric circuit therein and disposed in substantially parallel relationship to said first electronic component;
at least two electrode pads provided on a surface of said first electronic component facing said second electronic component and electrically connected to the internal electric circuit of said first electronic component, one of said at least two pads being disposed adjacent a central portion of said first electronic component, the other pad being disposed adjacent an outer peripheral edge of said first electronic component;
at least two electrode pads provided on a surface of said second electronic component facing said first electronic component, said at least two pads being respectively disposed substantially in alignment with the pads of said first electronic component; and
metallic bonding elements disposed between said first and second electronic components for electrically and mechanically connecting together the respective pads of said first electronic component and the pads of said second electronic component;
the ratio of the surface area of one of the pads of at least one of said first and second electronic components to the volume of the metallic bonding element connected to said one pad is different from the ratio of the surface area of the other pad of said one electronic component to the volume of the metallic bonding element connected to said other pad;
each of the pads of said first and second electronic components being bonded to an associated metallic bonding element over substantially the whole area of the pad, whereby the shape of the metallic bonding element connected to said one pad of at least one of said first and second electronic components is different from the shape of the metallic bonding element connected to said other pad.
According to the electronic component unit of the present invention having the above structure, the shapes of the at least two metallic bonding elements can be selected so that they are suitable for, for example, the thermal expansion characteristics of the electronic component unit, and so that, of the metallic bonding elements respectively connected to the at least two pads of at least one of the two electronic components, the metallic bonding element disposed adjacent the outer peripheral edge of the one electronic component has higher durability to stress than the other metallic bonding element. This contributes to an improvement in the reliability of solder connections for electrically and mechanically connecting the two electronic components.
In an electronic component unit in accordance with a preferred embodiment of the present invention, the surface area of the one pad of the at least one of the electronic components is different from the surface area of the other pad, and the volume of the metallic bonding element connected to the one pad of the at least one of the electronic components is substantially the same as the volume of the metallic bonding element connected to the other pad.
In the electronic component unit, the surface area of the one pad may be either greater or smaller than the surface area of the other pad.
In an electronic component unit in accordance with another preferred embodiment of the present invention, the surface area of the one pad of the at least one of the electronic components is substantially the same as the surface area of the other pad, and the volume of the metallic bonding element connected to the one pad of the at least one of the electronic components is different from the volume of the metallic bonding element connected to the other pad.
In each of the electronic component units in accordance with both embodiments, the first electronic component may be a semiconductor package comprising a substrate and a semiconductor chip, the substrate having first and second surfaces, the at least two pads being provided on the first surface, and the semiconductor chip being mounted on the second surface. The second electronic component is a circuit substrate.
Alternatively, in the electronic component unit, the first electronic component may be a semiconductor chip and the second electronic component may be a substrate.
In the electronic component unit of the present invention, each of the first and second electronic components may preferably have at least three pads. In this case, the pad intervals may be different or changed from the central portions toward the outer peripheral edges of the electronic components.
Each of the metallic bonding elements preferably comprises a solder material containing at least one metal selected from the group consisting of Pb, Sn, Ag, Au, In and Sb.
The metallic bonding element connected to the one pad of the at least one of the first and second electronic components may comprise a solder material having a melting point different from that of the solder material of the metallic bonding element connected to the other pad.
Each of the pads may preferably have a two layer structure comprising a Ni layer and an Au layer.
In the electronic component unit of the present invention, the first electronic component may preferably have many pads including the at least two pads, the many pads being respectively disposed at intersections of phantom longitudinal and lateral lines which form a lattice pattern, and the second electronic component may have many pads disposed substantially in alignment with the pads of the first electronic component. The ratios of the areas of the pads to the volumes of the metallic bonding elements may preferably change in the direction from the central portions toward the outer peripheral edges of the electronic components.
The ratios of the areas of the pads to the volumes of the metallic bonding elements may increase or decrease in the direction from the central portions toward the outer peripheral edges of the electronic components.
In accordance with a second feature of the present invention, there is provided an electronic component having an internal electric circuit therein and adapted to be electrically and mechanically connected to another electronic component through metallic bonding elements, said component having:
a surface to be connected to said another electronic component; and
at least two pads electrode disposed on said surface and electrically connected to said internal electric circuit;
each of said at least two electrode pads having a surface having a property of being wetted with a molten metal of said metallic bonding elements;
said at least two electrode pads being adapted to be electrically and mechanically connected to said another electronic component through said metallic bonding elements;
one of said at least two pads being disposed adjacent a center of said surface, the other pad being disposed adjacent an outer edge of said surface; and
the surfaces of said at least two pads having different areas.
Therefore, if solder balls used for forming the metallic bonding elements respectively connected to the pads have the same volume and are melted to form bumps, the resultant shapes of the bumps are different from each other. This consequently provides advantages the same as those obtained from the first feature of the present invention.
In the electronic component, the surface area of the one pad may be either greater or smaller than the surface area of the other pad.
Each of the pads may preferably have a two layer structure comprising a Ni layer and an Au layer.
Many pads including the at least two pads may preferably be provided on the surface, the many pads may be respectively disposed at intersections of phantom longitudinal and lateral lines which form a lattice pattern, and the pad interval may vary in the direction from the central portion toward the outer peripheral edge of the surface.
In accordance with a third feature of the present invention, there is provided an electronic component assembly comprising:
an electronic component having an internal electric circuit therein;
at least two electrode pads electrically connected to said internal electric circuit and provided on a surface of said electronic component so as to be connected to another electronic component, one of said at least two pads being disposed adjacent a center of said surface, the other pad being disposed adjacent an outer edge of said surface; and
metallic bonding elements respectively disposed on said at least two pads to form bumps;
said at least two pads having surfaces having a property of being wetted with a molten metal of the metallic bonding elements; and
the ratio of the area of said one pad to the volume of the metallic bonding element connected to said one pad being different from the ratio of the area of said other pad to the volume of the metallic bonding element connected to said other pad.
This structure of the present invention also provides advantages the same as those obtained from the first and second features of the present invention.
In the electronic component assembly, the electronic component may be a semiconductor package comprising a substrate and a semiconductor chip, the substrate may have first and second surfaces, the at least two pads may be provided on the first surface, and the semiconductor chip may be mounted on the second surface.
Alternatively, in the electronic component assembly, the electronic component may be a semiconductor chip and the at least two pads may be provided on a surface of the semiconductor chip.
In the electronic component assembly, the electronic component may be a substrate and the at least two pads may be provided on a surface of the substrate.
In the electronic component assembly, the surface area of the one pad may be different from the surface area of the other pad.
In the electronic component assembly, the volume of the metallic bonding element connected to the one pad may be substantially the same as the volume of the metallic bonding element connected to the other pad.
In an electronic component assembly in accordance with a preferred embodiment of the present invention, at least three pads are provided on the surface, and the pad interval changes in the direction from the central portion toward the outer peripheral edge of the surface.
In the electronic component assembly, each of the metallic bonding elements may comprise a solder material containing at lest one metal selected from the group consisting of Pb, Sn, Ag, Au, In and Sb.
In the electronic component assembly, the metallic bonding element disposed on the one pad may comprise a solder material having a melting point different from the melting point of the solder material of the metallic bonding element disposed on the other pad.
In the electronic component assembly, each of the pads may have a two layer structure comprising a Ni layer and an Au layer.
In the electronic component assembly, many pads including the at least two pads may preferably be provided on the surface, the many pads may be respectively provided on the intersections of phantom longitudinal and lateral lines which form a lattice pattern, and the ratios of the areas of the pads to the volumes of the metallic bonding elements may change in the direction from the central portion toward the outer peripheral edge of the surface. The ratios of the areas of the pads to the volumes of the metallic bonding elements may increase in the direction from the central portions toward the outer peripheral edges of the electronic components, or may decrease in the direction from the central portion toward the outer peripheral edge of the surface.
The above and other objects, features and advantages of the present invention will be made more apparent from the description of preferred embodiments with reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary sectional view of an electronic component unit in accordance with an embodiment of the present invention;
FIG. 2 is a bottom view of a semiconductor package of the electronic component unit shown in FIG. 1, showing electrode pads provided on the bottom of the package;
FIG. 3 is a flow chart showing the process of forming solder bumps on the pads;
FIG. 4 is a drawing illustrating the concentrations of stresses caused in solder bumps having different shapes;
FIG. 5 is a graph showing the relation between the shapes of bumps and the temperature cycle lives thereof;
FIG. 6 is a sectional view of an electronic component unit in accordance with another embodiment of the present invention;
FIG. 7 is a sectional view of an electronic component unit in accordance with a further embodiment of the present invention;
FIG. 8 is a sectional view of the electronic component unit provided with solder junction portions formed by the conventional method; and
FIG. 9 is an enlarged fragmentary partial sectional view of a portion of the electronic component unit shown in FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(Embodiment 1)
FIG. 1 is a sectional view of a semiconductor device in accordance with an embodiment of the present invention. In FIG. 1, a semiconductor chip 1 is bonded by a bonding agent 2 to a wiring surface of a substrate 3 having electrical wiring formed thereon. An insulating paste is used as the bonding agent 2. The substrate 3 comprises a plate of glass fiber/epoxy resin material on which two to ten electric wiring layers are provided. Alternatively, the substrate 3 may comprise paper/phenolic resin.
Pad wires 4 on the semiconductor chip 1 are connected to upper electrodes of the substrate 3 by bonding. Each of the wires 4 comprises a gold or aluminum wire having a diameter of 25 or 30 μm. The wires 4 and the semiconductor chip 1 are protected by resin bonding or sealed by embedding them in a molded resin 5. Electrical signals are supplied from the semiconductor chip 1 to the electrodes of the substrate 3 through the wires 4 and reach lower electrode pads 6 through layered wiring in the substrate serving as conduction portions. Each of the pads 6 forms a bump forming region.
As shown in FIG. 2, the electrode pads 6 are disposed at equal intervals of 1.3 mm on intersections of phantom longitudinal and lateral lines which form a lattice. The pads 6 are each formed preferably by forming a Ni plated layer on a Cu wiring of the substrate and then forming an Au plated layer on the Ni layer. With the pad interval of 1.3 mm, the pads 6 are of a circular shape and have diameters which vary from 0.4 mm to 0.65 mm in seven stages with an increment of 0.05 mm in the direction from the center to the outer edge of the substrate 3. Returning to FIG. 1, solder balls 8 are respectively disposed on the thus formed pads 6 to form bumps. In this embodiment, each of the solder balls used for forming the electrode bumps has a diameter of 0.6 mm.
The pads of the substrate are bonded to electrodes pads 7 (bump forming regions) on a large circuit substrate 9 for mounting (mounting substrate) by melting the solder balls 8. Each of the pads 7 on the circuit substrate 9 defines a circular region having the same size as that of the pad 6 disposed in opposite relationship thereto on the substrate 3.
The solder balls 8 are previously arranged in a cassette corresponding to the arrangement of the pads 6 of the substrate 3 and then are transferred to the lower side of the substrate 3 to which solder paste is coated. Since the paste coated on the pads 6 alone has viscosity, the solder balls 8 are provisionally fixed to predetermined positions of the substrate 3, i.e., to the pads 6.
FIG. 3 is a flow chart showing a typical process of bonding the solder balls used in the present invention. Namely, the solder balls 8 are prepared in Step 21 and then arranged in a cassette in Step 23. On the other hand, a solder paste is coated in Step 24 on the chip mounting substrate 3 prepared in the Step 22. The solder balls 8 are then transferred to the substrate 3 (Step 25), followed by drying (Step 26) and heating in a furnace (Step 27) to form bumps (Step 28). Thereafter, the electrode pads 7 of another component (circuit substrate 9) to be bonded are aligned to and bonded to the balls 8 on the substrate 3, i.e., the thus formed bumps. A body to be bonded is not limited to the substrate 3, and the balls may be transferred to any bodies to be bonded (Step 25).
This bonding is performed by placing the substrate 3, having the bumps formed by the solder balls 8 on the lower side thereof, and the circuit substrate 9 such that the bumps 8 on the substrate 3 respectively contact the pads 7 of the circuit substrate 9 to form an assembly, heating the assembly in a reflow furnace at a temperature higher than the melting point of the solder bumps to re-flow the solder, taking out the assembly from the furnace and then cooling the assembly.
In the embodiment shown in FIG. 1, as described above, the electrode pads 6 on the lower surface of the substrate 3 have circular shapes, and the areas of the pads decrease stepwise in the direction from the center (the point of the intersection of longitudinal and widthwise center lines C L1 and C L2 shown in FIG. 2) to the outer edge of the substrate 3. On the other hand, since the solder balls 8 used for forming the bumps have substantially the same diameters, the volumes of the solder balls which adhere to all pads 6 of the substrate 3 are substantially the same. Further, the surfaces of the electrode pads 6 of the substrate 3 which respectively form the bump forming regions comprise Au films and thus have a property of being easily wetted with melted solder. The areas and wettability of the electrode pads 7 formed on the surface of the circuit substrate 9 are the same as those of the pads 6. For these reasons, when the assembly is heated to a temperature higher than the melting point of the solder bumps 8, the solder bumps are melted and respectively adhered and bonded to all areas of the pads 6 respectively associated with the bumps as well as to all areas of the pads 7 respectively associated with the pads 6. However, the melted solder is not adhered to portions of the surfaces of the substrate 3 and the circuit substrate 9 where the electrode pads 6 and 7 are absent. Since the area of the pad 6d adjacent to the outer edge of the substrate 3 is greater than the area of the pad 6a in the central portion of the substrate 3, the amount of the melted solder adhered to the pad 6d is greater than the amount of the melted solder adhered to the pad 6a. Similarly, the amount of the melted solder adhered to the pad 7d adjacent to the outer edge of the circuit substrate 9 is greater than that the pad 7a in the central portion of the substrate 9. The thus-formed bump 8d has a shape (a so-called "hand drum shape") in which the diameter of the central portion in the vertical direction is smaller than the diameter of each of the pads 6d and 7d. Each of the bumps 8a respectively adhered to the pads 6a in the central portion of the substrate 3 has a shape (a shape close to a sphere) in which the diameter of the central portion in the vertical direction is greater than the diameter of each of the pads 6 and 7. Each of the bumps 8b and 8c adhered to the pads 6b and 6c has a shape intermediate the shapes of the bumps 8a and 8d.
The relation between the shape of a bump and the life (durability to stress) is described below with reference to FIGS. 4 and 5. FIG. 4 shows bumps C and D as examples. The contact angles of bump C with respect to the substrate 3 and the circuit substrate 9 are designated by θ c1 and θ c2 , respectively, while the contact angles of bump D with respect to the substrate 3 and the circuit substrate 9 are designated by θ d1 and θ d2 , respectively. As is apparent from FIG. 4, the contact angles θ c1 and θ c2 are smaller than the contact angles θ d1 and θ d2 , respectively.
The substrate 3 and the circuit substrate 9 expand with heat, the amounts of the thermal expansions of the substrate 3 and the circuit substrate 9 are different because the thermal expansion coefficients thereof are different. The relative displacement between the substrate 3 and the circuit substrate 9 due to the difference in thermal expansion therebetween causes stresses in all bumps. For the bump C having the smaller contact angles θ with respect to the substrates 3 and 9, the stresses caused by the relative displacement are concentrated in the corners of the junctions between the bump C and the substrates 3 and 9, thereby easily damaging the bump C and the junctions between bump C and the substrates 3 and 9. On the other hand, for the bump D having the relatively larger contact angles θ, the stress is concentrated in the central portion (an intermediate portion between the substrates 3 and 9) of the bump D as viewed in the vertical direction thereof. The more the shape of a bump is close to a hand drum shape, the more the stress is concentrated in the central portion of the bump as viewed in the vertical direction thereof.
FIG. 5 shows the relation between strain and stress in bumps of various shapes and the temperature cycle lives of the bumps. This relation was obtained when various bumps were subjected to relative displacements of the same amounts. As is apparent from FIG. 5, assuming that the relative displacements applied to the bumps are the same, the operative lives of the bumps increase, and the reliability of solder junctions thus increase, as the shapes of the bumps change from a spherical shape to a hand drum shape.
The relative displacement between the substrates 3 and 9 due to the-difference in the thermal expansion is small in the central portions of these substrates, while the relative displacement is large in the portions of the two substrates adjacent the outer edges thereof. In FIG. 4, arrows C 1 and C 2 indicate a relative displacement caused between the substrates 3 and 9 due to the difference in the thermal expansion which is applied to the bump C, and arrows D 1 and D 2 indicate a relative displacement caused between the substrates 3 and 9 due to the difference in the thermal expansion which is applied to the bump D. Since the bump D is more distant from the central portions of the substrate 3 and the circuit substrate 9 (i.e., portions having substantially no relative displacement due to the difference in the thermal expansion between the substrate 3 and the circuit substrate 9) than the bump C is, i.e., bump D is closer to the outer edges of the substrates 3 and 9, the relative displacement D 1 -D 2 is greater than the relative displacement C 1 -C 2 . This is true with the embodiment of the present invention shown in FIG. 1. Namely, in the embodiment shown in FIG. 1, the relative displacement between the substrates 3 and 9 increases in the direction from the central portions of the substrates 3 and 9 (portions with substantially no relative displacement due to the difference in the thermal expansion therebetween) toward the outer edges thereof. Therefore, the stresses caused in the bumps adjacent the outer edges of the substrates 3 and 9 are greater than the stresses caused in the bumps adjacent the central portions thereof. However, since the shapes of the bumps 8 change from spherical to a hand drum shape in the direction from the central portions of the substrates 3 and 9 toward the outer edges thereof, the bumps adjacent the outer edges can resist larger stress and relative displacement.
The solder junctions, i.e., the bumps 8, serve as means for electrically connecting the circuit substrate 9 and the substrate 3 of the semiconductor chip package. However, since stresses are caused in the connecting means due to thermal deformation of the two substrates 3 and 9, the reliability in respect of strength of the connecting means is considered most significant. In the solder junctions according to the present invention, since the bumps in which larger stresses are caused have higher durability, as described above, the durability of the solder junctions as a whole between the two substrates is improved, with an increase in reliability, as compared with the conventional solder junctions. The present invention thus permits a practical use of a high-performance semiconductor package suitable for multi-pin packaging and high-speed processing.
In addition, in solder-mounting of packages such as QFP (Quad Flat Package), SOP (Small Outline Package), BGAP (Ball Grid Array Package), etc., it was difficult to prepare bumps having different shapes in a single package for decreasing stress. However, the present invention can easily change the shapes of bumps in a component of a BGAP without using a special jig or apparatus and, thus, enables the advantageous practical use of the BGAP as a multi-pin, package which can be made at high speed.
It is also possible to ensure amounts of solder necessary for forming bumps by applying thick layers of solder to the pads by a printing method in place of the use of the solder balls 8. A substrate 3 to which solder is thus applied and a circuit substrate 9 are placed opposite to each other and soldered through a re-flow process to form a solder connection. In this connection structure, each of the bumps adjacent the outer peripheries of the substrates has a hand drum shape.
Some semiconductor packages are liable to warp in an angular manner (the central portion is projected upwardly) according to the internal structures thereof. In such a case, since the circuit substrate 9 has rigidity and is flat, tensile loads more easily occur in the bumps in the central portion of the package. Therefore, the pads in the central portion of the package are made larger than the pads adjacent the outer periphery of the package so that each of the bumps in the central portion of the package has a hand drum shape.
In regard to the relations among the areas of the pads 6 of the substrate 3, the areas of the pads 7 of the circuit substrate 9 and the diameters of the solder balls 8, the areas of the pads 7 of the circuit substrate 9 may be varied, while the sizes of the pads 6 of the substrate 3 and the diameters of the balls 8 are constant. Alternatively, the diameters of the solder balls 8 may be varied while the areas of the pads 6 of the substrate 3 and the areas of the pads 7 of the circuit substrate 9 are constant. Further, the sizes of the pads 6 of the substrate 3 may be different while the areas of the pads 7 of the circuit substrate 9 and the diameters of the solder balls 8 are constant.
(Embodiment 2)
FIG. 6 is a sectional view of a semiconductor device in which, after wire bonding, a semiconductor chip 1 is die-bonded to a substrate 3' of a biphenyl resin and then sealed in a resin 5. In FIG. 6, electric signals are passed through internal layer wiring of the substrate 3' to lower electrode pads 6. The pads 6 are arranged at equal intervals of 1.3 mm at intersections of phantom lines which form a lattice pattern. When the interval of the pads 6 is 1.3 mm, each of the pad regions has a circular form. The diameters of the pads disposed within a region of the substrate 3' which is inward of the midway between the center and the outer edge of the substrate are each 0.5 mm, and the diameters of the pads within the outer half area of the substrate are each 0.6 mm. Each of solder balls 8a used for forming bumps has a diameter of 0.6 mm. Each of the solder balls 8a adjacent the center of the substrate 3' comprises Sn/Ag (95/5) and has a melting point 221° C., while each of the solder balls 8b adjacent the outer edge comprises Sn/Pb (60/40) and has a melting point 183° C. The solder balls 8 are all previously arranged in a cassette corresponding to the arrangement of the pads 6 of the substrate and then are transferred to the substrate 3' to which paste is applied. The substrate 3' to which the solder balls 8 are applied and the circuit substrate 9 are placed opposite to each other and then soldered together through a re-flow process.
When the substrates 3 and 9 which are placed one on the other are slowly taken out from the reflow furnace, the solder (Sn/Ag: 95/5) having the higher melting point is first solidified and the solder (Sn/Pb: 60/40) having the lower melting point is then solidified.
There is no difficulty in use of solder containing In and Sn as the solder materials having different melting points. When solder materials having different melting points are used, the diameters of balls of different solder materials may be varied, while the areas of the pads 6 of the substrate and the areas of the pads of the circuit substrate 9 are constant. Alternatively, the areas of the pads of the substrate 3' and the areas of the pads of the circuit substrate 9 may be varied, while the diameters of the balls of different solder materials are constant.
(Embodiment 3)
FIG. 7 is a sectional view showing a state where an Si chip 1' is directly mounted on a ceramic four-layer wiring substrate 10 and connected thereto. The Si chip 1' contains functional units for operation, memory and control which are connected by a wiring network. Pads 6' at the wiring end are arranged in a lattice pattern. The pads 6' are formed by laminating thin metallic films and applying an Au film to the outermost layer of the laminated films. Each of the pad regions in the central portion of the chip 1' has a rectangular form of 60 μm×60 μm, the sizes of the pad regions being changed stepwise in the direction from the central portion toward the outer edge of the chip 1'. Each of the solder balls 8 has a composition consisting of Pb/Sn: 5/95 and a diameter of 60 μm. These solder balls were arranged in a cassette corresponding to the positions of pads 7 of the substrate 10. The sizes of the pads 7 of the substrate 10 respectively correspond to the pads 6' of the chip 1'. After the substrate 10 and the cassette are placed opposite to each other, they are put in a furnace for melting the solder balls to transfer the solder to the pads 7 of the ceramic substrate 10. The Si chip 1' with the pads 6' is then placed on the substrate 10, and they are bonded.
There is no difficulty in use of two or three types of balls having different melting points, rather than balls comprising a single material, as the solder balls 8 for forming bumps. In some cases, the sizes of the pads 7 of the substrate 10 and the pads 6' of the chip 1' may be constant, or they may change stepwise, or the areas of the pads 7 of the substrate 10 may be about 1.5 times as large as the areas of the pads 6' of the chip 1'. | An electronic component unit is provided with two electronic components which are disposed in parallel with each other and each of which has an internal electric circuit therein. Electrode pads are provided on the opposed surfaces of the two electronic components and are electrically connected to the internal electric circuits. The pads on one of the electronic components are respectively electrically and mechanically connected to the corresponding pads on the other electronic component by solder bumps. The areas of the pads increase or decrease stepwise in the direction from the central portions toward the outer peripheral edges of the two electronic components, while the volumes of the solder bumps are constant. Alternatively, the volumes of the solder bumps decrease or increase in the direction from the central portions toward the outer peripheral edges of the two electronic components, while the areas of all pads are constant. Each of the pads of the two electronic components is bonded to an associated solder bump over the whole area of the pad, whereby the shapes of the solder bumps respectively connected to the pads of the two electronic components change in the direction from the central portions toward the outer peripheral edges of the two electronic components to provide the solder bumps with different durabilities to stress, thereby assuring high reliability of the connection between the two electronic components. | 8 |
This application claims priority from Provisional Application Ser. No. 60/188,596 filed Jan. 14, 2000, which is incorporated herein by reference.
BACKGROUND
1. Field
The present invention is directed to a hinge, and in particular, to a hinge providing two pivot axes for two degrees of movement and greater range of motion.
2. Prior Art
Enclosures utilize hinges on covers or doors to provide access to the interior of the enclosure. Hinges often mount along the side of the enclosure so that the door does not close under its own weight. It can be appreciated that a device for preventing an enclosure door from closing and swinging freely would be advantageous to provide access to the interior of the enclosure for an extended period of time. Normal door and hinge construction often do not have closure devices and the balance and weight of the door prevent accidental closure. However, in some instances, it may be advantageous to have a door that includes a structural stop that allows opening and closing, but requires greater force to close so that the door may be held in an open position. This is especially important in outdoor conditions where wind may engage the planar surface area of the door and tend to open or close a door. Another common problem with doors and the hinges is providing sufficient mobility to the cover. In hinge and door combinations wherein the door opens only approximately 180 degrees, the door is extended away from the enclosure and as it is exposed, the door may be subject to closure from the wind or may endure forces in an opposite direction to closing that may cause damage to the hinge or even break off the hinge. This situation also occurs in enclosures having a cover on the top that opens and the door lies substantially horizontal and exposed in the open position. Although there are doors that open to a greater range of motion, workers often will place objects on the door or lean on the door in the open position, often damaging the hinge or breaking the door.
Door and hinge systems are known that provide a greater range of motion. However, such systems typically require special mounting arrangements and decrease the utility or the exterior appearance. Such systems may also limit the access to the interior of the enclosure. In addition, the systems do not provide any resistance to the door closing, so that the door may still accidentally swing shut such as when exposed to wind forces. Further disadvantages of such systems are the type of motion required often causes damage to gaskets that are wiped or rubbed by the cover during some portion of the opening and closing motion.
It can be seen then that a new and improved closure and hinge system is needed. Such a system should provide free range of motion so that the door may open against the side of the closure to minimize wind effect. Such a system should also provide resistance to accidental closure and provide a range of motion that does not damage or wear gaskets on the enclosure cover. The present invention addresses these as well as other problems associated with enclosures and hinges.
SUMMARY OF THE INVENTION
The present invention relates to a hinge, and in particular to a compound hinge, that provides two axes of rotation and a wide range of motion between the hinged elements.
The compound hinge includes a first base hinge link mounting to a first element. The first link includes raised knuckle portions for receiving a hinge pin therethrough. The base portion has recesses formed therein for receiving mounting devices such as screws or bolts for attachment to the first element. Intermediate the knuckles are arcing surfaces configured for receiving and aligning lug portions of a second link. The receiving portions are proximate a pair of opposed stop members that flex slightly and are flexed when pushed by the corresponding lugs. The stop portions act as a toggle to retain the hinge in position. The knuckles may also include stop portions for positioning the second link relative to the first link. A second link includes two sets of knuckles for receiving hinge pins. The first knuckle is configured for aligning with and having orifices coaxial with the knuckles of the first link. The second link is aligned so that the first set of knuckles and second set of knuckles are parallel with lugs extending substantially perpendicular to and aligned with the axes of the knuckles. The lugs are configured to extend into the receiving portions of the first link. The first knuckle is aligned with the knuckles of the first element and the second set of knuckles on the second link receive the pin for attaching to the second element. In this manner, the second link is hinged relative to the first link and the second link is also hinged relative to the second element. The first knuckle also includes complementary stop portions cooperating with the stop portions of the knuckles of the first link to limit relative rotation. The knuckles may also form a toggle device in one embodiment, providing further rotational resistance at a predetermined rotational position.
When assembled, the lugs engage the receiving surface and are held in place by the stop portions of the base on the first link member. As the cover or door is opened and rotated relative to a second link, it will reach its full range of motion, but it will be possible to open the door further relative to the first element, such as a housing. At this point, continued rotation will press the lugs against the stop elements and cause the stop elements to flex slightly until the lugs push beyond the stop elements. The second hinge member is then free to rotate relative to the first hinge member and an additional range of rotation is achieved.
To close the hinge, the second element rotates relative to the second hinge member, wherein the complementary stop portions engage and resist rotation. However, as further rotation occurs and the second element reaches its full range of motion relative to the second hinge member, further rotation of the second element causes the lugs to flex the stop elements and allow the lugs to push past the stop portions and return to the original position.
The arrangement of the present invention provides a simple, reliable hinge that provides a wide range of motion. In addition, the toggling effect from the lugs engaging the stop elements act as a retainer to hold the door in either the opened or closed position. However, with continued pressure, the door can be easily closed. The present invention is easy to assemble and can be retrofitted to other existing door and enclosures.
These features of novelty and various other advantages that characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings that form a further part hereof, and to the accompanying descriptive matter, in that there is illustrated and described a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an end sectional view of a compound hinge according to the principles of the present invention in a closed position;
FIG. 2 shows an end sectional view of the hinge shown in FIG. 1 in a partially open position;
FIG. 3 shows an end sectional view of the hinge shown in FIG. 1 in a fully open position;
FIG. 4 shows an end sectional view of the hinge shown in FIG. 1 in a partially open position;
FIG. 5 shows a perspective view of a first link for the compound hinge shown in FIG. 1;
FIG. 6 shows a sectional view of the first link taken along line 6 — 6 of FIG. 5;
FIG. 7 shows a perspective view of a second link for the hinge shown in FIG. 1 complementary to the link shown in FIG. 5;
FIG. 8 shows a sectional view of the second link taken along line 8 — 8 of FIG. 7;
FIG. 9 shows a bottom plan view of a door for an enclosure according to the principles of the present invention;
FIG. 10 shows a sectional view of the door taken along line 10 — 10 of FIG. 9;
FIG. 11 shows a top plan view of an enclosure according to the principles of the present invention;
FIG. 12 shows a sectional view of the enclosure taken along line 12 — 12 of FIG. 11;
FIG. 13 shows an end sectional view of a second embodiment of a compound hinge according to the principles of the present invention in a closed position;
FIG. 14 shows an end sectional view of the hinge shown in FIG. 13 in a partially open position;
FIG. 15 shows an end sectional view of the hinge shown in FIG. 13 in a fully open position;
FIG. 16 shows a perspective view of a first link for the compound hinge shown in FIG. 13;
FIG. 17 shows a sectional view of the first link taken along line 17 — 17 of FIG. 16;
FIG. 18 shows a perspective view of a second link for the hinge shown in FIG. 13 complementary to the link shown in FIG. 16; and
FIG. 19 shows a perspective view of the second link for the hinge shown in FIG. 13 complementary to the link shown in FIG. 16 with a pin element replacing a flange portion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the Figures, and in particular to FIG. 1, there is shown a portion of an enclosure 20 having a compound hinge 22 . The hinge 22 pivotally connects a cover or door 26 to a housing 24 . As shown in FIGS. 2-4, the compound hinge 22 provides two separate axes of rotation, providing a greater range of motion and freedom of movement between the door 26 and the housing 24 .
Referring now to FIG. 9, the door 26 is shown in greater detail. The door typically includes bracing around the periphery thereof, the door forms a channel 42 receiving a gasket 44 , as shown in FIG. 10, for forming a seal with the housing 24 , as shown in FIG. 1 . As shown in FIG. 9, the cover includes recesses 46 formed along one edge of the door 26 for mounting the hinge 22 and aligned bores 48 for receiving a hinge pin 28 (not shown in FIG. 9) for providing pivotal movement between the hinge 22 and the door 26 . Along the opposite edge of the door 26 is a latch 40 .
Referring now to FIGS. 11 and 12, the door receiving portion of the housing or enclosure 24 is shown. Although the housing 24 may be a molded monolithic element, it may include a collar 30 forming a rectangular opening fitting against upper edges of sides of the housing 24 , as shown in FIG. 12 . The collar 30 includes an inner ridge 32 that extends upward and engages the gasket 44 in the closed position, as shown in FIG. 1 .
The collar 30 also may include mounting holes 38 and alignment studs 34 that engage the base of the first link member, as explained hereinafter. The collar 30 also forms a channel 36 that inserts over the top of the wall edges of the housing 24 .
Referring now to FIGS. 5 and 6, a first link member 50 is shown. The first link member 50 includes a base portion 52 having a pair of mounting holes 58 formed therethrough. The mounting holes 58 are aligned even with first hinge knuckles 54 that are coaxially aligned to receive a hinge pin 28 . The first knuckles 54 include stop portions 56 of about 90 degrees. The radially extending end surfaces of the stop portions 56 cooperate with complementary surfaces on a second link member, as explained hereinafter. Intermediate the first knuckles 54 are lug receiving recesses 60 formed in the base portion 52 . The lug receiving recesses 60 are receive the corresponding lugs of the second link, as explained hereinafter. Stop fingers 62 are spaced apart from the lug receiving recesses 60 . The stop fingers 62 act as a surface engaging the lugs. With spaces on both sides of the fingers 62 and with the fingers being attached at only one end, the fingers 62 flex, allowing the lugs to toggle so that the second link may rotate, as explained hereinafter.
Referring to FIG. 7, a second link member 70 is shown that is configured for pivotally mounting, as shown in FIGS. 1-4, to the door 26 and the first link member 50 . The second link member 70 includes a second knuckle 72 , third knuckles 74 and lug portions 76 . The second knuckle 72 includes a bore 88 formed therethrough and is configured to receive a hinge pin 28 for pivotally mounting to the cover 26 . The second knuckle 72 includes an arcing surface 78 to provide clearance during rotation relative to the cover 26 . Ends of the second knuckle 72 include stop portions 92 of approximately 90 degrees. The radial end surfaces of the stops 92 are complementary to and cooperate with the ends of the stop portions 56 . Referring again to FIG. 7, third knuckles 74 include an arcing outer surface 82 providing for rotation relative to the base 52 of the first link member 50 . The third barrel 74 also includes a bore 90 receiving a hinge pin for connection to the first knuckle 54 of the first link member 50 . Extending downward from the lower portion of the third barrel 74 are the lugs 76 . The lugs 76 include a camming surface 84 forming a corner 86 . The lugs 76 are spaced and configured for inserting into the recesses 60 on the first link member 50 . The second link member 70 is aligned relative to the first link member 50 by the corner portion 86 of the lugs 76 engaging the corresponding stop fingers 62 . The rotation can be accomplished by the lugs 76 pushing against the stop members 62 until the fingers 62 flex and allow rotation. The camming surface 84 rotates, sliding against the flexed associated stop finger 62 .
Referring again to FIG. 1, with the compound hinge 22 in the closed position, the cover 26 is shut against the housing 24 so that the gasket 44 presses against the ridge 32 of the collar 30 to form a seal. The second link 70 is in a substantially vertical position with the camming surface 84 of the lug 76 resting against the lug engaging surfaces 60 . The corners 86 of the lugs 76 rest against the stop finger 62 of the first link member 50 .
The radially extending ends of the stop portions 92 of the second knuckle 72 of the second link member 70 cooperate with the corresponding stop portions 56 of the first link member 50 to prevent further rotation in the clockwise direction, as taken from the end view in FIG. 1 .
As the cover 26 is opened, the cover 26 rotates relative to the second link member 70 , which remains stationary from the closed position. The resistance of the fingers 62 engaging the lugs 76 prevents rotation of the second link member 70 relative to the first link member 50 while the cover 26 rotates with less resistance.
The cover 26 reaches its maximum range of motion relative to the second link member 70 at approximately 180 degrees of travel by the outer edge of the recessed portion 46 of the cover 26 engaging the outer side of the second link 70 . Further rotation of the cover 26 relative to the second link member 70 is not possible so that in normal use, the cover 26 tends to stay at the position shown in FIG. 2 . Further rotational force applied to the cover 26 tends to rotate the second link member 70 in a counter clockwise direction, as shown in FIG. 2 . This pressure causes a torque around the hinge pin 28 extending through the first and second knuckles, applying pressure against the fingers 62 . As the lugs 76 push the fingers 62 and cause the fingers 62 to flex out of the way, the hinge 20 passes through a toggle point until the cover 26 reaches the position shown in FIG. 3 . This provides approximately a 270 degree range of motion. At the position shown in FIG. 3, the cover 26 is substantially parallel to and extending along the edge of the housing 24 so that there can be almost no effect from wind catching the door and closing it.
When the cover 26 is closed, the stop fingers 62 are again pushed by the lugs 76 , but in the opposite direction and resist clockwise rotation, as shown in FIG. 4 . However, the door 26 is free to rotate above the axis of rotation passing through the second knuckle 72 and rotate back to the position shown in FIG. 4 . The cover 26 rests against the side of the second link 70 and further rotation of the cover 26 relative to the second link member 70 is not possible. In addition, the fingers 62 resist rotation so that the door will not close until additional pressure is applied and the fingers 62 are forced to flex by the lugs 76 . As the fingers 62 flex to the right as viewed in FIGS. 1-4, the lugs 76 can travel back to the position shown in FIG. 1 and the cover 26 is again closed.
However, the additional resistance needed to flex the fingers 62 provides slightly increased resistance so that the cover 26 stays in the open position without the additional force to overcome the resistance being applied.
Referring to FIGS. 13-19, there is shown a second embodiment of a compound hinge, generally designated 120 , in accordance with the principles of the present invention. The compound hinge 120 is similar to the hinge 20 , except that a toggle device 180 is added to provide more rotational resistance for holding the hinge in a predetermined position. The toggle device 180 includes a recess 182 formed in a first knuckle 154 of a first hinge member 150 , and a second knuckle 172 of a second hinge member 170 . The arcing periphery of the first knuckle 154 , or the complementary surface of the second knuckle 172 , includes a raised flange portion 184 which is configured for extending partially into a complementary recess 182 in the other of the first knuckle 154 or second knuckle 174 at the toggle position.
When the toggle device 180 is engaged, as shown in FIGS. 13 and 14, the first and second knuckles 154 and 172 have greater resistance to relative rotation. As the cover 26 is rotated about the second hinge member 170 , the first and second knuckles 154 and 172 have a mechanical stop which prevents the first hinge member 150 and second hinge member 170 from rotating relative to one another. Further rotation requires slightly more effort to disengage the toggle assembly 180 and allow rotation between the first hinge member 150 and the second hinge member 170 . As shown in FIG. 18, the flange portion 184 may be molded into the second knuckle 172 . In addition, as shown in FIG. 19, the second knuckle 172 may include a recess 186 with a pin member 188 extended into both the recess 182 and the recess 186 . As with the flange 184 , the pin member 188 also provides resistance and the same toggle effect. The toggle assembly 180 provides proper resistance so that the hinge 120 may be held in a predetermined position. Although the toggle assembly 180 is shown at the apex of the first knuckle 154 , it can be appreciated that, if a toggle position is required at a different location along the range of rotation, it may be easily moved. In addition, the recess 182 and raised portion 184 may be reversed while still achieving the desired toggle effect.
The design of the present invention provides a simple hinge mechanism that allows a 270 degree range of motion. In addition, the collar 30 and hinge 20 or 120 provide for retrofitting enclosures to accept such a system. The system also has rotation about a two different axes and fingers that act as a stop member that prevents the door from swinging closed without force sufficient to cause flexure of the fingers 62 . Since the cover 26 rotates about an axis remote from the enclosure housing 24 , the cover does not rub the gaskets, so that a better and longer seal is maintained.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in that the appended claims are expressed. | A compound hinge system includes a first link and a second link. The first link includes knuckles and arcing engaging surfaces next to stop portions that are configured for receiving engaging lug portions on a second link member. A second link member includes first and second sets of knuckles. One of the sets of knuckles cooperates with a hinged pin to pivot relative to the first link while the second set of knuckles receives a hinge pin to pivot relative to the second element. The lugs slide relative to the engaging surface and push against the stop portions to flex them outward and require additional force to move between various stops in the range of motion. | 8 |
RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 387,079, filed June 10, 1982, abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to novel substituted 5-(pyrrol-2-oyl)-1,2-dihydro-3H-pyrrolo [1,2-a]pyrrole derivatives and their corresponding salts, esters, nitriles, amides and substituted amides. Unlike the known pyrrolo[1,2-a]pyrrole derivatives of U.S. Pat. No. 4,097,579, which are limited to 5-unsubstituted pyrryl derivatives, the new compounds of the present invention have 5-pyrryl groups substituted with various groups including alkyl, 5-S-alkyl, ##STR1## 5-SO 2 -alkyl, 5-alkyl, 5-N-alkyl, 5-O-alkyl or 5-halo. It has been a well-known fact that such hetero-substituted pyrroles are difficult to prepare due to the sensitive nature of the pyrrole system. Furthermore, the compounds of this invention are found to possess higher analgesic/anti-inflammatory activities but exhibit much lower ulcerogenic irritation than the prior art compounds. For a chronic disease, for example, arthritis, it is crucial that the anti-inflammatory/analgesic agent be administered routinely and regularly at an effective dosage level without causing gastric irritation or ulcer. Accordingly, it is an object of the present invention
(1) to provide novel nonsteroidal anti-inflammatory and analgesic agents with high potency but lower ulcerogenic side effect;
(2) to develop processes for the preparation of the novel 5-(substituted pyrrol-2-oyl)-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole derivatives;
(3) to provide methods of application of the novel compounds in the treatment of inflammatory diseases, the relief of pain and fever or inhibition of platelet aggregation; and
(4) to provide pharmaceutical compositions and formulations for the administration of these novel compounds.
DETAILED DESCRIPTION OF THE INVENTION
This invention relates to novel 5-(substituted pyrrol-2-oyl)-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole derivatives of the structural formula: ##STR2## or a pharmaceutically acceptable salt, ester or amide thereof wherein
R is
(a) hydrogen;
(b) loweralkyl especially C 1-6 linear or branched alkyl such as methyl, ethyl, propyl, isopropyl, t-butyl, pentyl, and hexyl;
(c) lowercycloalkyl especially C 3-6 cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl;
(d) lower(cycloalkyl-alkyl) especially C 4-8 (cycloalkyl-alkyl) such as cyclopropylmethyl, cyclopentylmethyl, cyclohexylmethyl and cyclohexylethyl;
(e) loweralkenyl especially C 2-8 alkenyl such as 2-propenyl, 2-methyl-2-butenyl and 3-ethyl-2-pentenyl;
(f) halo-loweralkyl especially halo C 1-6 alkyl such as chloromethyl, trifluoromethyl, 1-chloroethyl and 2,2-difluorobutyl; or
(g) phenyl- or substituted phenyl-loweralkyl especially phenyl-C 1-3 alkyl such as benzyl, 4-chlorobenzyl, 2-fluorobenzyl, and phenylpropyl.
groups (a)-(g) above being unsubstituted or substituted by loweralkyl, loweralkoxy, halo, cyano, carboxy, sulfonamino, carbamoyl, sulfonyl, sulfinyl, azido, amino, substituted amino such as loweralkylamino or diloweralkylamino, haloalkyl, carboxyalkyl, carbamoylalkyl, N-sustituted carbamoylalkyl or a combination thereof;
R 1 is hydrogen, haloloweralkyl or loweralkyl especially C 1-6 alkyl as previously defined;
R 2 Z can be at any available ring positions and R 2 is R as previously defined;
n is 1 to 3;
R 3 is
(a) hydroxy;
(b) loweralkoxy especially C 1-6 alkoxy as defined previously;
(c) amino;
(d) loweralkylamino especially C 1-6 alkylamino such as cyclohexylamino, methylamino, isopropyl amino, n-butylamino or t-butylamino;
(e) diloweralkylamino especially di(C 1-6 alkyl)amino such as diethylamino, or dimethylamino;
(f) morpholinyl;
(g) bis(hydroxyloweralkyl)amino especially bis(hydroxy C 1-6 alkyl)amino such as bis(hydroxyethyl)amino;
(h) loweralkylcyclohexylamino especially C 1-6 alkylcyclohexyamino such as methylcyclohexylamino; or
(i) glucosamino;
(j) lower(alkanoyloxyalkoxy), especially C 1-6 (alkanoyloxyalkoxy) such as 1-(pivaloyloxy)ethoxy or 1-(acetoxy)ethoxy;
(k) aroyloxylweralkoxy especially 1-(benzoxy)ethoxy;
(l) lower(alkoxycarbonyloxyalkoxy) especially C 1-6 (alkoxycarbonyloxyalkoxy) such as 1-(ethoxycarbonyloxy)ethoxy;
(m) aryloxycarbonyloxyloweralkoxy especially aryloxycarbonyl C 1-6 alkoxy such as 1-(benzyloxycarbonyloxy)ethoxy;
(n) tri(loweralkylamino)loweralkoxy especially tri (C 1-6 alkoxy such as choline-oxy;
(o) lower(alkanoylaminoalkoxy), especially C 1-6 (alkanoylaminoalkoxy) such as acetamidoethoxy;
(p) imidoloweralkoxy especially imido C 1-6 alkoxy such as 1-(succinimido)ethoxy;
(q) heterocyclyloxy, for example, phthalidyloxy, or 2-pyridyloxy;
(r) hydroxyloweralkoxy especially hydroxy C 1-6 alkoxy such as hydroxypropoxy;
(s) loweralkoxyalkoxy especially C 1-6 (alkoxyalkoxy) such as methoxyethoxy, ethoxyethoxy or methoxymethoxy;
(t) di(loweralkylamino)loweralkoxy especially di(C 1-6 alkylamino) C 1-6 alkoxy such as dimethylamino ethoxy, dimethylamino-propoxy, or diethylamino propoxy;
(u) N-pyrrolidinylloweralkoxy especially N-pyrrolidinyl C 1-6 alkoxy such as N-pyrrolidinylethoxy or N-pyrrolidinyl methoxy and N-methyl-2-pyrrolidinylmethoxy;
(v) N-piperidinylloweralkoxy especially N-piperidinyl C 1-6 alkoxy such as N-piperidinylethoxy;
(w) N-morpholinylloweralkoxy especially N-morpholinyl C 1-6 alkoxy such as N-morpholinylethoxy; or
(x) 4-methyl-1-piperazinylloweralkoxy especially 4-methyl-1-piperazinyl C 1-6 alkoxy such as 4-methyl-1-piperazinylethoxy;
Y is oxygen, sulfur, sulfinyl, sulfonyl, CH 2 --or hydrogen providing that when Y is hydrogen, R does not exist; and
Z is --O--, --S--, --SO--, --SO 2 --, --NH--, --CH 2 or halo especially fluoro, chloro or bromo providing that when Z is halo, R 2 does not exist.
The preferred embodiment of this invention comprises compounds of formula (I) wherein
R is
(a) hydrogen or C 1-6 alkyl as previously defined;
(b) C 2-4 alkenyl such as 2-propenyl or propenylmethyl;
(c) halo-C 1-6 alkyl as previously defined; or
(d) phenyl-C 1-3 alkyl such as benzyl;
R 1 is hydrogen or C 1-6 alkyl;
R 2 Z is at position 5, i.e. adjacent to N and is R as defined above;
n is 1;
R 3 is hydroxy, C 1-6 alkoxy, or lower(alkanoylaminoalkoxy), especially C 1-6 alkanoylaminoalkoxy such as acetamidoethoxy;
Y is oxygen, sulfur, CH 2 -, or H when R is absent; and
Z is --S--, --CH 2 --, or halo when R 2 is absent.
The most preferred embodiment of this invention comprises compounds of structural formula (I) wherein R 1 is C 1-3 alkyl especially methyl or absent;
R 1 is hydrogen or methyl;
R 2 Z is at position 5 and R 2 is hydrogen, methyl, or absent;
n is 1;
R 3 is hydroxy, C 1-6 alkoxy or acetamidoethoxy;
Y is oxygen, CH 2 --, or H with the proviso that when Y is H, R is absent; and
Z is --S--, --CH 2 --, or halo with the proviso that when Z is halo, R 2 is absent.
The representative compounds of this invention comprise:
(1) 5-(5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(2) ethyl 5-(5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(3) 5-(5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid; or
(4) ethyl 5-(5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(5) 5-(5-isopropyl-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(6) ethyl 5-(5-isopropyl-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate; or
(7) 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(8) ethyl 5-(1-methyl-5-methylthio-2-pyrroyl-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(9) 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(10) ethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(11) 5-(1-methyl-5-isopropyl-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(12) ethyl 5-(1-methyl-5-isopropyl-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(13) 5-(1-methyl-5-ethylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(14) 5-(1-methyl-5-n-propylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(15) 5-(1-methyl-5-methoxy-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(16) 5-(1-methyl-5-ethoxy-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(17) 5-(1-methyl-5-n-propyloxy-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(18) 5-(1-trifluoromethyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid;
(19) ethyl-5-(1-methyl-5-ethylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(20) ethyl 5-(1-methyl-5-n-propylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(21) ethyl 5-(1-methyl-5-methoxy-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(22) ethyl 5-(1-methyl-5-ethoxy-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(23) ethyl 5-(1-methyl-5-n-propyloxy-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate;
(24) ethyl 5-(1-trifluoromethyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate; or
a sodium or lysine salt of the carboxylic acids described above.
It is intended that compounds of the present invention include their corresponding optical isomers (d-, l-, or dl-form) especially the l-isomers. The asymmetric center of the compound is as shown below at carbon number one: ##STR3##
The novel compounds of the present invention can be prepared by the precursor IIa as shown in the following scheme: ##STR4## wherein R, Y, R 1 , R 2 , Y and Z are as previously defined and R 4 is hydrogen, loweralkyl especially C 1-6 alkyl such as methyl, ethyl, isopropyl, t-butyl, pentyl, or cyclohexyl, and R 5 is hydrogen, t-butyl, benzhydryl or other acid-removable protecting groups which can be removed under mild conditions.
According to the scheme above, IIa is decarboxylated under neutral, acidic or basic conditions or by itself (neat). When the decarboxylation is conducted under basic conditions, the precursor of formula IIa is usually heated with a base (Table II) in an appropriate solvent at about 50°-250° C. preferably about 90°-150° C. for about 0.5-48 hours or until the decarboxylation is substantially complete.
The most commonly utilized solvents comprise
(1) water;
(2) C 1-5 alkanol especially methanol, ethanol, isopropanol and t-butyl alcohol;
(3) lower ketone, e.g., acetone and methylethylketone;
(4) lower ether including 1,2-dimethoxyethane, tetrahydrofuran (THF), dioxane and diglyme;
(5) a mixture of at least two of the solvents described in (1) to (4) especially aqueous solutions thereof.
TABLE I
Organic Bases Used in Decarboxylation
Tri-(loweralkyl)amine, e.g.,
triethylamine
pyrrolidine
pyridine
collidine
When acidic decarboxylation is applied, for example, IIa is refluxed in trifluoroacetic acid to give Ia which is then subject to various known modifications such as hydrolysis (when R 4 is not H), ammonialysis, ester exchange etc. to afford (I). Other acids may also be used. For example, those listed below in Table II.
TABLE II
Acids Used in the Decarboxylation
(1) An acid of the structural formula: ##STR5## wherein R 6 and R 8 independently are hydrogen or halo such as iodo, bromo, chloro or fluoro preferably chloro or fluoro; and R 7 is H, C 1-6 alkyl, halo especially chloro or fluoro, or halo-C 1-6 alkyl such as trifluoromethyl, trichloromethyl, 1,1-difluoroethyl, or 1-chloro-1-fluoropropyl or the like.
(2) Preferred Acids:
Acetic acid
Chloroacetic acid
Chlorodifluoroacetic acid
Dichloroacetic acid
Difluoroacetic acid
Trifluoroacetic acid
Trichloroacetic acid
Pentafluoropropanoic acid
The acidic decarboxylation may be conducted in an acid or in an inert solvent containing the acid. The solvents which are often used are illustrated below in Table III.
TABLE III
Solvents for the Acidic Decarboxylation
Toluene
Benzene
Xylene
Tetrahydrofuran
1,2-Dimethoxy-ethane
Dioxane
Methylene chloride
Acetic Acid
The decarboxylation temperatures may vary with the acids or solvents being used. Usually the temperatures range from about 30° to about 120° C. Under the optimum conditions, i.e., in refluxing trifluoroacetic acid with or without solvent, the temperature ranges from about 35° to about 75° C.
Generally, the decarboxylation is substantially complete after heating at an appropriate temperature for about 1 to about 20 hours or under more favorable conditions, about 0.5 hours to about 5 hours.
The prescursors of formula IIa are readily prepared from condensation between a pyrrolo[1,2-a]-pyrrole moiety and a substituted pyrrole derivative as shown below in scheme (a): ##STR6## wherein R, R 1 , R 2 , R 4 , R 5 , Y and Z are as previously defined.
Alternatively where Z is --S--, --O--, or --NH--, IIa may be obtained via the following scheme (b): ##STR7##
The starting materials (IIIa and IIIb) are known or readily preparable by procedures described in copending application Ser. No. 373,692, filed May 31, 1982 (our Case 16617IA) and U.S. Pat. No. 4,097,579. These two disclosures are herein incorporated by reference.
The pharmaceutically acceptable salts of the acids of the Formula I are readily prepared by conventional procedures well-known in the art. For example, an acid of Formula I is treated with an appropriate amount of a base, such as an alkali or alkaline earth metal hydroxide, e.g. sodium hydroxide, potassium hydroxide, calcium hydroxide, or an organic base such as an amine, e.g., triethylamine, lysine, dibenzylethylenediamine, piperidine, pyrrolidine, benzylamine and the like.
The pharmaceutically acceptable esters of the acids of structural formula (I) are prepared by conventional methods. For example,
(1) A compound of Formula (I) is treated with a lower alkanol or phenol in the presence of an acid such as sulfuric acid, hydrochloric acid and any one or a combination of the acids illustrated above in Table (II) or ion exchange resins.
(2) A compound of Formula (I) is converted to an acid halide such as acid chloride or bromide via treatment with a halogenating agent such as thionyl chloride or phosphorus pentachloride, followed by reaction with an alcohol or a phenol. Other well-known methods such as those included in the "Compendium of Organic Synthetic Methods," I. T. Harrison et al., Wiley-Interscience, p. 272 (1971), may also be used.
Similarly, the pharmaceutically acceptable amides of the acids of Formula (I) are readily prepared by conventional methods. For example, the halides of the acids of Formula (I) can be treated with ammonia or substituted amines such as ethylamine, benzylamine or glucosamine to afford the corresponding amides. Other methods involving treatment of the acids with an amine in the presence of a catalyst such as DDC or tosylchloride may also be used.
The following examples are provided for illustrating but not limiting, the scope of the present invention.
EXAMPLE 1
Step A: Preparation of 1-Methyl-2-thiocyanopyrrole
Under nitrogen atmosphere, to a mixture of 25 g of KSCN in 60 ml of dry methanol at -78° C. was added 20 g of Br 2 dissolved in 45 ml of methanol. The resulting yellow solution was stirred for 5-10 minutes and 10.1 g of 1-methylpyrrole added in one portion. The mixture was allowed to warm to room temperature and stirred for an additional hour. The mixture was poured into 600 ml of ice-water and extracted twice with 200 ml of methylene chloride. The methylene chloride layer was washed, dried and then concentrated to yield 16.1 g of light yellow oil that turns reddish upon standing.
Step B: Preparation of 1-methyl-2-methylthiopyrrole
Under nitrogen atmosphere, to a mixture of 6.9 g of 1-methyl-2-thiocyanopyrrole and 14.2 g of CH 3 I at -30° C., 5.4 g of sodium methoxide was added an the temperature allowed to rise to 0° C. The reaction mixture boiled (exothermic reaction). Stirring was continued for 3 hours at ambient temperature. The filtrate was desolventized under reduced pressure to yield 5.75 g of light yellow oil. This product (clean by NMR) could be distilled at T 40° C. under vacuum and stored over K 2 CO 3 at 0° C.
Step C: Preparation of 1-methyl-5-methylthiopyrrole-2-acid chloride
To a solution of 12.7 g of 1-methyl-2-methylthiopyrrole in 100 ml of dry ether stirred over an atmosphere of nitrogen at 0° C., 11 g of phosgene dissolved in 20 ml of ether was added. This mixture was stirred at 0° C. for 4 hours and ambient temperature for 14 hours. Residual phosgene was removed with N 2 and solvent distilled off. The resulting solid product was recrystallized from hexane to yield 17 g of pink long needles, m.p. 67°-70° C.
Step D: Preparation of Ethyl 1-(2-hydroxyethyl)-3-carboethoxy-4-methylpyrrole-2-acetate
To a solution of 1500 ml of ethanolamine in 1250 ml of water at -20° C., 505 g of diethyl-1,3-acetonedicarboxylate was added and the mixture stirred for 125 minutes at 0° C. and then treated with 237 g of 1-chloroacetone. The reaction temperature was maintained below 10° C. After additional stirring at room temperature for 5 hours, the mixture was poured to 2 1 HCl-6 Kg ice and stirred for about 1/2 hour. The mixture was filtered and the residue washed thoroughly with H 2 O, and then hexane to yield 200 g of white product. m.p. 133°-135° C.
Step E: Preparation of Ethyl 1-(2-mesyloxyethyl)-3-carboethoxy-4-methylpyrrole-2-acetate
Ethyl 1-(2-hydroxyethyl)-3-carboethoxy-4-methylpyrrole-2-acetate (101.7 g) in 800 ml of dry methylene chloride at -10° C. was treated with 56 ml of triethylamine followed by addition dropwise 31 ml of methanesulfonyl chloride. After 30 minutes of stirring at room temperature, 250 ml of water was added and the organic layer separated and washed with water (3×300 ml ), dried over Na 2 SO 4 and evaporated under reduced pressure to yield 121.3 g of ethyl 1-(2-mesyloxyethyl)-3-carboethoxy-4-methyl-pyrrole-2-acetate as white crystals from ethylacetate hexane, m.p. 66°-68° C.
Step F: Preparation of Ethyl 1-(2-iodoethyl)-3-carboethoxy-4-methylpyrrole-2-acetate
Ethyl 1-(2-mesyloxyethyl)-3-carboethoxy-4-methylpyrrole-2-acetate (11.6 g) and 27 g of NaI was heated to reflux with 150 ml of acetonitrile for 1 hour. Solvent was removed by distillation and the residue triturated with water. The insoluble product was separated by filtration, air dried and crystallized from methylenechloride/hexane to yield 14.9 g of ethyl 1-(2-iodoethyl)-3-carboethoxy-4-methylpyrrole-2-acetate as a white solid.
Step G: Preparation of Diethyl 1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1,7-dicarboxylate
Ethyl 1-(2-iodoethyl)-3-carboethoxy-4-methyl-pyrrole-2-acetate in 65 ml of dry dimethylformamide was treated with 1.6 g NaH (60% in mineral oil) and stirred for 60 minutes at room temperature. The mixture was quenched with 100 ml of water and extracted with ethylacetate (3×100 ml). The ethyl acetate layer was washed with water, dried over MgSO 4 , filtered and evaporated to dryness to yield 6.4 g of crude diethyl 1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1,7-dicarboxylate to be used in the next step without further purification.
Step H: Preparation of Diethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1,7-dicarboxylate
Diethyl 1,2-dihydro-3H-pyrrolo-[1,2-a]-6-methylpyrrole-1,7-dicarboxylate (22.2 g) and 16 g of 1-methyl-5-methylthiopyrrole-2-acid chloride were dissolved in 250 ml of methylene chloride at 0° C. followed by dropwise treatment with 22 ml of SnCl 4 in 45 ml of methylene chloride. After additional stirring at ambient temperature for 3 hours, 250 ml 3N HCl was added and then stirred for 1 hour. The organic layer was separated, washed with water, dried over Na 2 SO 4 , filtered through silica and the filtrate mixed with equal volume of hexane and distilled to remove most of the methylene chloride and cooled to yield 30.5 g of diethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1,7-dicarboxylate as white crystals, m.p. 142°-3° C.
Step I: Preparation of 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo [1,2-a]-pyrrole-1,7-dicarboxylic acid
Diethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1,7-dicarboxylate (25 g) in 200 ml methanol, 50 ml H 2 O and 25 g KOH were heated to reflux for 8 hours. The resulting mixture was treated with 200 ml of std. NaCl and distilled to remove the methanol. The mixture was acidified with 6N HCl while stirring and then cooled. The crystalline mass obtained was separated by filtration, air dried and recrystallized from ethylacetate-ethanol to yield 21 g of 5-(1-methyl-5 -methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]-pyrrole-1,7-dicarboxylic acid, m.p. 212°-3° C.
Step J: Preparation of ethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylate-7-carboxylic acid
A solution of 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1,7-dicarboxylic acid (20 g) and 20 g of resin (Biorad AG 50W-XB, 20-50 mesh) in 500 ml of abs. ethanol was heated to reflux until the reaction was complete by TLC (6hrs). The solution was filtered hot and the crystalline product formed was recovered by a second filtration to yield 17.5 g of ethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]-pyrrole-1-carboxylate-7-carboxylic acid, m.p. 209°-211° C.
Step K: Preparation of ethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylate
Ethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate-7-carboxylic acid (1.65 g neat) was heated at 240° C. until bubbling of CO 2 stops (30 minutes). The resulting residue was then dissolved in 30 ml of methylene chloride and passed through a short column of silica. The filtrate was mixed with an equal volume of hexane and then distilled to its initial volume. Cooling gave 1.1 g of ethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylate as white crystals, m.p. 101°-2° C.
Following substantially the same procedure but using 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1,7-dicarboxylic acid as the starting material, there was obtained 5-(5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid.
EXAMPLE 2
5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylic acid
Ethyl 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate (500 mg) was stirred with 10 ml of methanol and 10 ml of 10% NaOH for two hours. 200 ml of saturated sodium chloride solution was added to the resulting mixture and the methanol distilled off under reduced pressure. The aqueous solution was acidified with 3N HCl while stirring, cooled and the resulting precipitate collected by filtration. The residue was washed with water, air dried and recrystallized from ethylacetate-hexane to yield 450 mg of 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid, m.p. 182°-184° C.
Alternatively, the title compound is prepared by decarboxylating of the corresponding diacid 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1,7-dicarboxylic acid in trifluoroacetic acid at about 30°-40° C. until the reaction is substantially complete. The mixture was quenched with water, extracted with methylene chloride and the methylene chloride layer was washed several times with 5% aqueous NaHCO 3 solution, dried and evaporated to yield 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylic acid.
EXAMPLE 3
Ethyl-5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole[1,2-a]pyrrole-1-carboxyate
Step A: Preparation of diethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2a]pyrrole-1,7-dicarboxylate
A solution of 16 g of diethyl 1,2-dihyro-3H-pyrrole[1,2a]-6-methylpyrrole-1,7-dicarboxylate-5-acid chloride and 6 g of 1-methyl-5-chloropyrrole in 100 ml methylene chloride was treated with 15 ml SnCl 4 at -35° C. and stirred at room temperature for 4 hours and worked up as described in Example 1, Step H to yield 14 g of crude product consisting of two compounds (α and β isomers). The α isomer was separated by column chromatography using silica gel as the solid support and 40:60 (ethyl acetate:hexane) as the mobile phase. The diester was crystallized from methylene chloride-hexane to yield 6.9 g of diethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2a]pyrrole-1,7-dicarboxylate, m.p. 124°-6° C.
Step B: Preparation of 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2a]pyrrole-1,7-dicarboxylic acid
6.0 g of the diester was hydrolyzed as in Example 1, Step I and 5.2 g of 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2-a]pyrrole-1,7-dicarboxylic acid was obtained.
Step C: Preparation of ethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2-a]pyrrole-1-carboxylate-7-carboxylic acid
A solution of 5 g 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1,7,dicarboxylic acid in 100 ml of ethanol was treated with 5 g of resin and was monoesterified as in Example 1, Step J, to yield 3.8 g of ethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2-a]pyrrole-1-carboxylate-7-carboxylic acid, m.p. 185°-187° C.
Step D: Preparation of ethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole[1,2,-a]pyrrole-1-carboxylate
Following substantially the same procedure as described in Example 1, Step K, ethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylate-7-carboxylic acid (3.5 g) was decarboxylated at 200° C. to afford 2.5 g of ethyl-5-(1-methyl-5-chloro-2-pyrroyl]-1,2-dihydro-6-methyl-3H-pyrrole[1,2-a]pyrrole-1-carboxylate.
EXAMPLE 4
N-acetylaminoethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2-a]pyrrole-1-carboxylate
A solution of 0.5 g of 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole[1,2-a]pyrrole-1-carboxylic acid 0.26 g N-acetylaminoethanol, 0.5 g DCC and 0.11 g of N,N-dimethylaminopyridine in 35 ml of methylene chloride was stirred at room temperature for 16 hours. The dicyclohexyl urea formed was filtered off and the residue dissolved in ether washed with water, 3×50 ml 5% acetic acid, 5% NaHCO 3 , dried and evaporated. Crystallization from ethylacetate gave 401 mg of N-acetylaminoethyl 5-(1-methyl-5-chloro-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylate, m.p. 156°-157° C.
EXAMPLE 5
Lysine salt of 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2-a]pyrrole-1-carboxylic acid
A solution of 0.5 g of 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2-a]pyrrole-1-carboxylic acid and 0.24 g lysine in 20 ml of methanol was stirred at 40° C. for 1 hour and then cooled and ether added slowly. The resulting precipitate was collected by filtration to afford 0.70 g of the Lysine salt.
Mass under m/e (M + -H 2 O), 446.
EXAMPLE 6
5-(1-methyl-5-methylsulfinyl-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrole-[1,2-a]pyrrole-1-carboxylic acid
A solution of 0.2 g of 5-(1-methyl-5-methylthio-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]-pyrrole-1-carboxylic acid in 20 ml chloroform and a few drops of dimethylsulfoxide was treated with 0.1 g of m-chloroperbenzoic acid (MCPBA) and stirred overnight. Hexane was then added carefully, and the mixture was cooled and the resulting yellow crystals was collected by filtration to give 195 mg of 5-(1-methyl-5-methylsulfinyl-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylic acid. m/e 334.
Similarly the corresponding sulfone is prepared by a similar procedure using 0.2 g of (MCPBA). After refluxing overnight, there is obtained 5-(1-methyl-5-methylsulfonyl-2-pyrroyl)-1,2-dihydro-6-methyl-3H-pyrrolo- [1,2-a]pyrrole-1-carboxylic acid.
The novel compounds of this invention are anti-inflammatory, and analgesic agents of value in the treatment of a wide variety of conditions where one or more of the symptoms of pain or inflammation are manifested, e.g., rheumatoid arthritis, osteoarthritis, gout, infectious arthritis, rheumatic fever and pain symptoms associated with other diseases. Furthermore, at similar dosage levels, they are found to be unexpectedly more effective than the prior art compound (U.S. Pat. No. 3,952,012), but exhibit a much lower incidence of undesirable gastric side effects. These observations are substantiated by side-by-side comparative data as shown below in Table IV.
______________________________________ ##STR8## (THLF(UD.sub.50).sup.a PBQ.sup.b (ED.sub.50) Adjuvant (ED.sub.50).sup.cCompound mg/kg mg/kg mg/kg______________________________________Prior ArtCompoundRZ = H 10 1 30R.sup.4 = C.sub.2 H.sub.5 No protection from bone and cartilage destruction at 30 mg/kgRZ = CH.sub.3 S 15 -- --R.sup.4 = HRZ = CH.sub.3 S 90R.sup.4 = C.sub.2 H.sub.5 0.17 7.5 Protection from bone and cartilage destruction at 10 mg/kgRZ = Cl 15R.sup.4 = H 2.1 --______________________________________
a. Gastric Hemorrhage:
The GHLF test is conducted according to the following procedure:
Rats (Sprague-Dawley, Males, 120-180 gm) were fasted overnight and dosed orally with drug suspended in 0.5% methylcellulose. The drug concentration was adjusted so that each animal received 1.0 ml/100 gm body weight. Four hours later the animals were killed by asphixiation in carbon dioxide, the stomachs removed, cut open and everted. The mucosal lining was washed and examined under 3X magnification. The lesions are indentified as perforations of the gastric mucosa many of which perforate right through the wall of the stomach.
The results are expressed in two ways, the average number of lesions per stomach, and the number of animals in the group showing at least one lesion.
b. Inhibition of phenylbenzquinone (PBQ) writhing in mice:
Groups of 10 male mice (C.B.L., CD 1 , 18-22 grams) were food deprived overnight prior to the experiments. Test substances, suspended or dissolved in 1% methylcellulose, were administered orally (0.1 ml/10 grams body weight) at various times prior to administration of PBQ (2.0 mg/kg i.p.). The mice were placed in individual boxes and observed for 10 minutes (5 to 15 minutes after PBQ). The number of "writhes" (abdominal contraction, lordosis and hindlimb extension) for each animal was recorded and the group means and standard errors were calculated. The means obtained from drug treated groups were compared with the vehicle control mean values and percent inhibition of writhing was calculated as follows: ##EQU1##
c. Rat adjuvant arthritis test (adjuvant)
The test was done in accordance with procedures well-known in the art (see: C. A. Winter, Arthr. Rheum 9, 394-404 (1966).
For treatment of inflammation, fever or pain, the compounds of the invention may be administered orally, topically, parenterally, by inhalation spray or rectally in dosage unit formulations containing conventional non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles. The term parenteral as used herein includes subcutaneous injections, intravenous, intramuscular, intrasternal injection or infusion techniques. In addition to the treatment of warm-blooded animals such as mice, rats, horses, dogs, cats, etc., the compounds of the invention are effective in the treatment of humans.
The pharmaceutical compositions containing the active ingredient may be in a form suitable for oral use, for example, as tablets, troches, lozenges, aqueous or oily suspensions, dispersible powders or granules, emulsions, hard or soft capsules, or syrups or elixirs. Compositions intended for oral use may be prepared according to any method known to the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from the group consisting of sweetening agents, flavoring agents, coloring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparation. Tablets contain the active ingredient in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture of tablets. These excipients may be for example, inert diluents, such as calcium carbonate, sodium carbonate, lactose, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example, maize starch, or alginic acid; binding agents, for example starch, gelatin or acacia, and lubricating agents, for example magnesium stearate, stearic acid or talc. The tablets may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate may be employed.
Formulations for oral use may also be presented as hard gelatin capsules wherein the active ingredient is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules wherein the active ingredient is mixed with water or an oil medium, for example peanut oil, liquid paraffin, or olive oil.
Aqueous suspensions contain the active materials in admixture with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, sodium alginate, polyvinylpyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be a naturally-occurring phosphatide, for example lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides, for example polyoxyethylene sorbitan monooleate. The said aqueous suspensions may also contain one or more preservatives, for example ethyl, or n-propyl, p-hydroxybenzoate, one or more coloring agents, one or more flavoring agents, and one or more sweetening agents, such as sucrose or saccharin.
Oily suspension may be formulated by suspending the active ingredient in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, or in a mineral oil such as liquid paraffin. The oily suspensions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as those set forth above, and flavoring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an antioxidant such as ascorbic acid.
Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those already mentioned above. Additional escipients, for example sweetening, flavoring and coloring agents, may also be present.
The pharmaceutical compositions of the invention may also be in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, for example olive oil or arachis oils, or a mineral oil, for example liquid paraffin or mixtures of these. Suitable emulsifying agents may be naturally-occurring gums, for example gum acacia or gum tragacanth, naturally-occurring phosphatides, for example soy bean, lecithin, and esters or partial esters derived from fatty acids and hexitol anhydrides, for example sorbitan mono-oleate, and condensation products of the said partial esters with ethylene oxide, for example polyoxyethylene sorbitan monooleate. The emulsions may also contain sweetening and flavoring agents.
Syrups and elixirs may be formulated with sweetening agents, for example glycerol, sorbitol or sucrose. Such formulations may also contain a demulcent, a preservative and flavoring and coloring agents. The pharmaceutical compositions may be in the form of a sterile injectable aqueous or oleagenous suspension. This suspension may be formulated according to the known art using those suitable dispersing or wetting agents and suspending agents which have been mentioned above. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example as a solution in 1,3-butane diol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil may be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid find use in the preparation of injectables.
The compounds of the invention may also be administered in the form of suppositories for rectal administration of the drug. These compositions can be prepared by mixing the drug with a suitable non-irritating excipient which is solid at ordinary temperatures but liquid at the rectal temperature and will therefore melt in the rectum to release the drug. Such materials are cocoa butter and polyethylene glycols.
For topical use, creams, ointments, jellies, solutions or suspensions, etc., containing the anti-inflammatory agents are employed.
Dosage levels of the order to 0.2 mg to 140 mg per kilogram of body weight per day are useful in the treatment of the above-indicated conditions (10 mg to 7 gms. per patient per day). For example, inflammation is effectively treated and anti-pyretic and analgesic activity manifested by the administration from about 0.5 to 50 mg of the compound per kilogram of body weight per day (25 mg to 3.5 gms per patient per day). Advantageously, from about 2 mg to about 20 mg per kilogram of body weight per daily dosage produces highly effective results (50 mg to 1 gm per patient per day).
The amount of active ingredient that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. For example, a formulation intended for the oral administration of humans may contain from 5 mg to 5 gm of active agent compound with an appropriate and convenient amount of carrier material which may vary from about 5 to about 95 percent of the total composition. Dosage unit forms will generally contain between from about 25 mg to about 500 mg of active ingredient.
It will be understood, however, that the specific dose level for any particular patient will depend upon a variety of factors including the activity of the specific compound employed, the age, body weight, general health, sex, diet, time of administration, route of administration, rate of excretion, drug combination and the severity of the particular disease undergoing therapy. | Substituted 5-(pyrrol-2-oyl)1,2-dihydropyrrolo[1,2-a]-pyrrole derivatives have been prepared via decarboxylation of the corresponding 1,7-dicarboxylate prepared from condensation of a dialkyl 1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-7-dicarboxylate-7-carboxylic acid with an appropriately substituted 2-pyrroyl chloride, or conversely, an acid chloride of the former bicyclic compounds with a substituted pyrrole. The compounds are analgesic and anti-inflammatory agents of high activities but low ulcerogenic side effects. | 8 |
BACKGROUND OF THE INVENTION
Electric door strikes are commonly used in various places of business where it is desired to control entry into a secured area by means of a remote switch. As an example, the lobby of a building might be separated from the rest of the facility by a door that is secured by an electric door strike. When an individual or group of individuals has been cleared for entry into the main part of the building, the receptionist or security guard depresses a momentary switch causing the door strike to be unlocked for a set period of time. The door strike then returns automatically to the locked condition.
There are four general versions or operating modes of the electric door strike, commonly referenced as follows:
Fail Secure/Direct Control
Fail Secure/Timed Release
Fail Safe/Direct Control
Fail Safe/Timed Release
In the Fail Secure mode, a loss of power leaves the door strike in the locked condition. The solenoid that drives the strike may be powered only briefly to unlock the door, and, because of the low duty cycle, the average power demand is low. In certain applications (i.e. employer entrance doors) the fail secure strike may be powered for eight or more hours. Reducing the voltage to a "hold-in level" after initial pull in is useful here also.
In the Fail Safe mode, the door strike is unlocked by a loss of power. Fail Safe strikes are powered continuously except while the door is unlocked. This constitutes a high duty cycle with relatively high average power demands. To prevent overheating in this operating mode, the voltage supplied to the solenoid should be reduced to a holding voltage after pull-in.
Under Direct Control, the strike is held in an unlocked condition as long as the switch is depressed. When the switch is released, the strike returns to the locked condition. Depressing the switch removes power to unlock for Fail Safe and applies power to unlock for Fail Secure.
In the Fail Secure/Timed Release mode or the Fail Safe/Timed Release mode, the doorstrike remains unlocked for a set period of time following a momentary switch closure. Again, power is removed to unlock under Fail Secure and is applied to unlock under Fail Safe.
The installers of electric door strikes are constantly confronted by a number of complications that arise because of the variety of operating modes. In addition, there is a lack of standardization in the industry relative to supply voltage for strike operation. Some strikes are designed to operate at 12, or 24 or up to 40 volts dc; others are designed for 12, 16 or 24 volts ac. Supply voltage from 12 to 40 volts dc or 12 to 28 volts ac may be present at a particular location, and the installer needs to match the device to the available voltage. One customer may require a relatively short release time; another may want a considerably longer release time. Because of the limited versatility and adjustability of prior art and presently available electric door strikes, the installer is required to stock a supply of the various versions of door strikes, and in some cases complicated adjustments have to be made at the site.
The goal of the present invention is to provide a versatile power and control circuit for an electric door strike that is immediately operable from any of the aforementioned voltage sources and is readily adaptable at the site for operation in any of the four different modes with readily adjustable release times. In addition, the present invention is directed toward the provision of a highly efficient power supply that permits miniaturization and prevents overheating in the confined space that is available for installation in the door jamb. The unit also minimizes heating of the door strike by reducing operating voltage to a hold-in level after initial powering.
SUMMARY OF THE INVENTION
In accordance with the invention claimed, a versatile, adaptable, adjustable and highly efficient power and control circuit is provided for an electric door strike.
It is, therefore, one object of this invention to provide an improved power and control circuit for an electric door strike.
Another object of this invention is to incorporate in such a power and control circuit the versatility and adaptability required for operation in any of the four common operating modes, namely Fail Secure/Direct Control, Fail Secure/Timed Release, Fail Safe/Direct Control and Fail Safe/Timed Release.
A further object of this invention is to provide in such a power and control circuit simple and convenient means for adjustment of release times over the expected range of customer requirements.
A still further object of this invention is to provide in such a power and control circuit a capability for operation from a variety of voltage or power sources including 12 to 40 volts dc and 12 to 28 volts
Yet another object of this invention is to provide such a power and control circuit in a highly efficient form that permits miniaturization and operation in the very confined quarters available in an ordinary door jamb.
A still further object of this invention is to reduce heating of the control circuit of an electric door strike by switching to a hold-in voltage.
Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be more readily described by reference to the accompanying drawings in which:
FIG. 1 is a schematic drawing of the power and control circuit of the invention;
FIG. 2 shows successive voltages or states of various elements of the power and control circuit through a complete cycle of operation for the Fail Secure/Direct Control operating mode;
FIG. 3 shows successive voltages or states of various elements of the power and control circuit through a complete cycle of operation for the Fail Secure/Timed Release operating mode;
FIG. 4 shows successive voltages or states of various elements of the power and control circuit through a complete cycle of operation for the Fail Safe/Direct Control operating mode; and
FIG. 5 shows successive voltages or states of various elements of the power and control circuit through a complete cycle of operation for the Fail Safe/Timed Release operating mode.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings by characters of reference, FIG. 1 discloses the electric door strike power and control circuit of the invention. The circuit comprises a power stage 20, a pulse width modulator (PWM) 21 and an operational control circuit 22 comprising first and second timers U1 and U2, and associated resistors and capacitors.
Power stage 20 comprises a bridge rectifier BR1, a PNP transistor Q2, an LC filter, L1 and C4, a filter capacitor C1, a recovery diode CR1, Q2 base-emitter resistor R1, Q2 base resistor R2, and solenoid recovery diode CR2.
The ac terminals 23 and 24 of bridge rectifier BR1 are connected to the ac or dc power source Vs, either directly (for Timed Release modes) or through a switch S3 (for Direct Control modes). The negative dc terminal 25 of bridge BR1 is connected to circuit ground 26 and the positive dc terminal 27 of BR1 is connected to the emitter 28 of Q2. Filter capacitor C1 is connected across the positive and negative terminals of bridge rectifier BR1 to provide a low ac impedance for the pulsed dc currents that are drawn from the power source as Q2 is turned ON and OFF by pulse width modulator 21. Filter capacitor C1 also filters the full-wave rectified voltage from bridge BR1. The collector 29 of Q2 is connected to the cathode of CR1 and to one end of L1. The other end of L1 is connected to the positive terminal of capacitor C4. The anode of CR1 and the negative terminal of C4 are connected to circuit ground 26. The base 31 of Q2 is connected to output terminal, pin 9 of PWM 31 by 510 ohm base resistor R2. A 1 K base-emitter resistor R1 is connected from base 31 to emitter 28 of Q2.
Pulse-width modulator U3 may be an integrated circuit of the type described as an MC34060A in the 4th Edition of Motorola's Linear/Switchmode Voltage Regulator Handbook (c Motorola Inc., 1989, P.O. Box 20912; Phoenix, Ariz. 85036).
Application information and specifications for the MC34060A are given on pages 443-453 of the above reference handbook where the circuit is described as follows:
The MC34060A is a fixed-frequency pulse width modulation control circuit, incorporating the primary building blocks required for the control of a switching power supply. . . . An internal-linear sawtooth oscillator is frequency-programmable by two external components, R T and C T . The approximate oscillator frequency is determined by: ##EQU1##
Output pulse width modulation is accomplished by comparison of the positive sawtooth waveform across capacitor C T to either of two control signals. The output is enabled only during that portion of time when the sawtooth voltage is greater than the control signals. Therefore, an increase in control-signal amplitude causes a corresponding linear decrease of output pulse width.
In the ordinary use of the pulse width modulator as a control circuit for a switching power supply, the pulse width modulator pulses the pass transistor ON and OFF at a fixed frequency and continuously adjusts the duty cycle (ratio of ON time to OFF time) as needed to regulate the output voltage to a fixed level.
In the case of the present invention, Q2 is the pass transistor. The pulsed dc voltage delivered by Q2 is filtered by L1 and C4. As Q2 is turned OFF, the energy stored in L1 tends to sustain the current through L1, and recovery diode CR1 provides a path for inductor current during the OFF time of Q2.
To facilitate a clearer understanding of the control exercised by operational control circuit 22 over pulse width modulator 21, details of the internal circuits of the pulse width modulator are shown in FIG. 1. The following features are incorporated.
1. A reference regulator (REF REG) 32 that supplies a precise +5 volts as a reference for the switching regulator;
2. A saw-tooth oscillator, (OSC) 33 with its frequency determined by external resistor R T and capacitor C T ;
3. A dead time comparator (DEAD TIME COMP) 34 which limits the maximum duty cycle of the switching regulator;
4. A pulse width modulator comparator, (PWM COMP) 35 which compares the output of an error amplifier with the output of the sawtooth oscillator, its output going high when the error amplifier output exceeds the instant voltage level of the sawtooth waveform;
5. Two error amplifiers, each driving the positive input of PWM COMP 35 through a diode OR gate (CR2, CR3) the first error amplifier being designated ERR AMP1 and the second, ERR AMP 2;
6. A NOR gate 36 with two input terminals, one connected to the output of DEAD TIME COMP 34 and the other connected to the output of PWM COMP 35;
7. An NPN transistor Q1 with its base controlled by the output of NOR gate 36.
Operational control circuit 22 enables the switching regulator comprising power stage 20 and pulse width modulator 21 as required to effect the desired operation of the electric door strike. Each operating cycle controlling the unlocking of the strike and the subsequent return of the strike to the locked condition is initiated by the actuation of a momentary switch, S1, S2 or S3. The timing required for the Timed Release modes is effected by means of the timers U1 and U2.
Timers U1 and U2 may be of the type described as a 555 timer on pages 9-3 to 9-8 of Fairchild's 1982 NA Linear data book (copyright 1982 Fairchild Camera and Instrument Corporation, 313 Fairchild Drive, Mountain View, Calif. 94042).
The 555 timer is an integrated circuit described in the data book as "a very stable controller for producing accurate time delays or oscillations. In the time delay mode, the delay time is precisely controlled by one external resistor and one capacitor; . . . By applying a trigger signal, the timing cycle is started and an internal flip-flop is set, immunizing the circuit from any further trigger signals".
During the delay time, the output terminal of the timer is at a positive voltage approaching the supply voltage (Vcc); at the end of the timing period the output falls to very nearly zero volts, depending on the value of current sink. Additional details of 555 timer operation are found in the Fairchild data book referenced earlier.
Timer U1 has its positive supply terminal, Vcc pin 8 connected to +5 V REF REG output 37 and its ground terminal, pin 1 connected to circuit ground 26. Adjustable timing resistor RT1 is connected from pins 6 and 7 to REF REG output 37 and timing capacitor CT1 is connected from pins 6 and 7 to circuit ground 26. Resistors R14 and R16 are serially connected from REF REG output 37 to ground 26 and the junction 38 between these two resistors is connected to the trigger terminal T R (pin 2 of U1) to bias the trigger terminal to +2.5 V. Momentary switch S1 has one terminal connected to ground 26; the other connected to U1 trigger terminal T r through a series capacitor, C8. The junction 39 of S1 and C8 is connected to REF REG output 37 through resistor R15. U1 output terminal (pin 3) is connected by series 100 K resistors R9 and R10 to REF REG output 37. An 0.1 μF capacitor C7 is connected from junction 39 to ground 26.
Timer U2 has its Vcc terminal, (pin 8) connected to +5 REF REG output 37. Its reset terminal R (pin 4) is also connected to REF REG output 37 through 47 K resistor R17. A capacitor C11 is connected from U2 pin 4 to ground 26. Ground pin 1 of U2 is connected to ground 26. An adjustable timing resistor RT2 is connected from U2 pins 6 and 7 to REF REG output 37 and a 4.7 μF timing capacitor C 2 is connected from pins 6 and 7 to ground 26. A 47 K resistor, R18 is connected from U2 trigger terminal T r (pin 2) to REF REG output 37 and momentary switch S2 is connected from pin 2 to ground 26. A capacitor C15 is connected from pin 2 to REF REG output 37. Output terminal 3 of U2 is connected through series 100 K resistors R11 and R13 to REF REG output 37. U2 output pin 3 is connected to the cathode of blocking diode CR3. A resistor R19 is connected to the anode of CR3 and to REF REG output 37. The anode of CR3 connects through C4 to pin 2 of U1.
Pulse width modulator 21 has its positive supply terminal (Vcc), pin 10 connected to the positive dc terminal of BR1. The frequency of OSC 33 is set by timing resistor R T 3, connected from pin 6 to ground 26 and timing capacitor C T 3, connected from pin 5 to ground 26. Ground pin 7 and deadtime control pin 4 are connected to ground 26. Resistors R3, R4A and R4B form a feed-back divider network connected from the power stage 20 output (VSOL) to ground 26 with the junction of R3, R4A and R4B connected to the non-inverting (+) input of ERR AMP 1. R4B may be disconnected at the installation site to alter the level of the regulated output voltage as needed to match the voltage rating of the solenoid. The inverting (-) input terminal of ERR AMP 1 is connected to +5 V REF REG output 37 by 4.7 K resistor R7 and to timer U1 output pin 3 by 13 K resistor R5. A stabilizing network C5 and R6 is connected from ERR AMP1 inverting input (pin 2) to PWM compensation terminal, pin 3. The non-inverting (+) input terminal (pin 14) of ERR AMP2 is connected to the junction 41 of R11 and R13; the inverting (-) input terminal (pin 13) of ERR AMP 2 is connected to the junction 42 of R9 and R10.
Operation of the electric door strike power and control circuit occurs as follows:
For the Fail Secure/Direct Control mode, switch S1 is not used and junction 39 is connected directly to ground 26. Switch S2 is also unused or not present, and operation is under the control of a normally open momentary switch S3 connected in series with ac or dc supply voltage Vs.
Operation in this mode is shown in FIG. 2 where voltages or states at various points in the circuit are shown for each successive stage of circuit operation. In FIG. 2, each column of voltages and states corresponds to a particular time interval. The first column of values shows voltages and states for the period prior to the closing of S3. The second column shows voltages and states for the period beginning with the closing of S3 and ending with the subsequent opening or release of S3. The third column shows voltages and states following the release of S3.
If S3 is still close when U1 times out, VSOL is removed. This is useful for allowing a strike to be energized for only a fixed time. In this configuration, trigger for U1 is provided at power-up by C7.
With switch S3 open all circuit voltages are at zero volts as indicated by the first column of FIG. 2. Because in the Fail Secure mode the door strike is held in the locked or latched condition by the return spring with no voltage applied to the solenoid, the strike is locked as indicated.
When S3 is closed, voltage is abruptly applied to the circuit and the conditions shown in the second column of FIG. 2 are set. With the trigger input of U1 (junction 39) tied to ground, the output of U1 is switched high as supply voltage is applied to U1 (output approaching +5 V). The output of U2 remains low. Both ends of divider R9/R10 are now at or near +5 V. ERR AMP 2 (-) is thus at +5 V (approx.) while ERR AMP 2 (+) is at +1.7 volts (With junction 39 at ground and U2 output low, junction 41 is set at 1/3 of +5 V by divider R11, R12, R13.) With ERR AMP 2 (-) more positive than ERR AMP 2 (+), the output of ERR AMP 2 (V3) is low. ERR AMP 1 now has complete control of the switching regulator. Solenoid voltage (VSOL) is at the full regulated level and the strike is unlocked. Note that if ERR AMP 2 output is high and more positive than the sawtooth oscillator output present at the negative input of PWM COMP 35, the output of PMM COMP 35 will be high also, causing the output of NOR gate 36 to be low. This condition turns Q1 and thus Q2 OFF for the remainder of the oscillator sawtooth period. Where the output of ERR AMP 2 is low (as in the present condition), ERR AMP 1 has control and controls the PWM duty cycle as appropriate to regulate the output of stage 20 to a voltage level determined by the reference voltage at pin 2 of PWM 21 and feedback divider R3/R4.
When S3 is released (opened) power is removed from the circuit, circuit voltages return to zero and the return spring drives the strike to the locked condition.
For the Fail Secure/Timed Release mode, power is continuously applied. Switch S3 remains closed or not present. Normally open momentary switch S1 is connected as shown in FIG. 1 from junction 39 to ground 26. Switch S2 is unused. Operation in this mode is shown in FIG. 3.
As shown in the first column of values during the period preceding the closing of S1, the outputs of U1 and U2 are at zero volts. Resistors R15, R11, R12 and R13 form a voltage divider between the +5 V output 37 of REF REG 32 and ground which sets the voltage at junction 41 and (ERR AMP 2) non-inverting or positive input at approximately 3.1 volts. Resistors R9 and R10 form a voltage divider which sets the voltage at junction 42 (and the inverting or negative input of ERR AMP 2) to 2.5 volts. With the non-inverting input of ERR AMP 2 being more positive than the inverting input, ERR AMP 2 output is high causing Q1 and Q2 to be turned off. Power stage output (VSOL) is thus at zero volts and the strike is locked.
When S1 is depressed (closed), R12 is pulled to ground (0 volts) and the voltage at the non-inverting input of ERR AMP 2 drops to 1.7 volts. At the same time, C8 couples a negative pulse to the trigger input (T r ) of U1. U1 responds as the trigger input drops below 1/3 the supply voltage (1.67 volts in this case). The output of U1 now switches to high (approaching +5 V). This takes both ends of R9/R10 voltage divider high, setting the inverting input of ERR AMP 2 to approximately +5 volts. With its inverting input more positive than its non-inverting input, ERR AMP 2 output goes low, allowing ERR AMP 1 to control the output of power stage 20. U1 has also placed both ends of the R5/R7 voltage divider at or near +5 volts. The output of power stage 20 is thus commanded to the full pull-in voltage for proper operation. The solenoid now drives the strike to the unlocked position.
The output of U1 remains high for a period of time equal to 1.1×R T 1×C T 1 which may be set at the desired value, typically between two and seven seconds.
At the end of the set period, the output of U1 returns low. If S1 has been released (opened), initial conditions are restored and power is removed from the strike. If S1 is still closed, the voltage at the inverting input of ERR AMP 2 returns to 2.5 volts. This is still greater than the 1.7 volts at the non-inverting input, so ERR AMP 1 retains control. With the output of U1 low, R5 and R7 set the voltage at the reference input (inverting input) of ERR AMP 1 to 3.75 volts, reducing the output of power stage 20 to the holding voltage. Releasing S1 now restores initial conditions, removing power from the strike, allowing the spring to return the strike to the locked condition.
Operation under Fail Safe/Direct Control is illustrated in FIG. 4. Junction 39 is tied to ground 26 as in the case of Fail Secure/Direct Control. Input power is supplied through a normally closed momentary switch S3. The outputs of U1 and U2 are low. The ERR AMP 2 inverting input is at 2.5 volts and the non-inverting input is at 1.7 volts causing ERR AMP 2 output to be low. ERR AMP 1 is thus in control and regulating output voltage, VSOL, to the holding voltage. For Fail Safe the strike is locked or latched when the solenoid is energized. The strike is thus held in the locked condition.
When S3 is depressed (opened), power is removed from the circuit and from the strike as shown in the second column of values of FIG. 4. With power removed, the return spring drives the strike to the unlocked condition.
When S3 is subsequently released (closed), power is restored to the circuit. With U1's trigger, T R , clamped to ground via C7, the output of U1 goes high as supply voltage rises. When the output of U1 goes high, both ends of the R9/R10 divider go high and the inverting input of ERR AMP 2 goes to 5 volts (more positive than the non-inverting input), and the output of ERR AMP 2 goes low, yielding control of the regulation loop to ERR AMP 1. While the output of U1 is high, the reference voltage at the inverting input of ERR AMP 1 is high and full pull-in voltage is delivered to the solenoid. The strike is thus driven by the solenoid to the locked condition.
The output of U1 remains high for a period equal to 1.1×R T 1×C T 1 holding VSOL to the full pull-in voltage. At the end of this period, the output of U1 falls to 0 volts, causing V5 to drop to 3.75 volts. This, in turn, causes the power stage output, VSOL to drop to the hold-in voltage. The strike now remains in the locked condition until the next operation of S3.
Operation under Fail Safe/Timed Release is illustrated in FIG. 5. For this mode of operation, power is continuously applied. Switch S3 is not present or is shorted out. Junction 39 is connected to ground 26 and operation is controlled by means of normally open momentary switch S2. The outputs of U1 and U2 are low as shown in the first column of values of FIG. 5. The inverting and non-inverting input terminals of ERR AMP 2 are at 2.5 volts and 1.7 volts, respectively, causing the output of ERR AMP 2 to be low and yielding control of the power stage to ERR AMP 1. With the output of U1 low, the power stage is at the holding level and the strike is locked.
A momentary closure of S2 triggers U2 causing the output of U2 to go high, initiating conditions shown in the second column of values of FIG. 5. The inverting and non-inverting inputs of ERR AMP 2 are at 2.5 volts and 3.3 volts, respectively. With the non-inverting input higher than the inverting input, ERR AMP 2 output goes high, taking control from ERR AMP 1 and turning off the power stage output. As voltage is thus removed from the solenoid, the return spring unlocks the strike.
The output of U2 remains high for a period of time equal to 1.1×R T 2×C T 2. At the end of this period, the output of U2 falls to zero. If S2 is still closed, the trigger input T r , of U2 is still low and the output of U2 remains high. The solenoid voltage remains at zero volts and the strike remains unlocked until S2 is released.
If S2 has opened at the end of the U2 time-out period, or at the time S2 is opened subsequent to time-out, the output of U2 falls to zero. This returns the non-inverting input of ERR AMP 2 to 1.7 v and control output voltage is yielded to ERR AMP 1.
The falling edge of U2's output triggers U1 via C14 and CR4 causing the output of U1 to go high. Conditions are now set as shown in the third column of values of FIG. 5.
With the inverting input higher than its non-inverting input, ERR AMP 2's output is low and ERR AMP 1 regulates output voltage. As long as the output of U1 remains high, the power stage output is regulated to the full pull-in voltage, energizing the solenoid and locking the strike. At the end of the U1 time-out period (1.1×R T 1×C T 1) the output of U1 falls to zero volts, taking V5 to 3.75 volts and causing the power stage output to be regulated to the reduced holding voltage.
The strike remains in the locked condition until the next operation of S2.
The electric door strike power and control circuit of the invention has been shown to be readily adaptable for operation in each of the four operating modes as illustrated in FIGS. 2-5. As these operating modes are considered, the following control characteristics may be noted:
For Fail Secure modes, the strike is locked when solenoid is not energized; for Fail Safe modes the strike is unlocked when the solenoid is not energized.
For Direct Control modes the unlocking operations are initiated and controlled by S3 which is normally open for Fail Secure and normally closed for Fail Safe.
For Fail Secure/Timed Release the unlocking operation is initiated by normally open momentary switch S1 and for Fail Safe/Timed Release the unlocking operation is initiated by normally open momentary switch S2.
Timer U1 controls the duration of the unlocked period for Fail Secure/Timed Release; timer U2 controls the duration of the unlocked period for Fail Safe/Timed Release.
For Fail Safe operating modes, full output (or pull-in) voltage is first applied to the solenoid as the strike is returned to the locked condition. The solenoid voltage is then reduced to a lower hold-in voltage to prevent over-heating of the solenoid and power stage 20 during the long periods of time between unlocked intervals.
The state of U1 determines the level of voltage delivered to the solenoid. When the output of U1 is high, full output or holding voltage is supplied; when the output of U1 is low, the reduced holding voltage is applied for the duration of the full output or pull-in.
The time-out periods of U1 and U2 are readily adjustable at the installation site as appropriate for the intended operating mode. Switches S1, S2 and S3 are external to the door strike assembly. For these reasons, a standard power and control circuit suffices for all four operating modes.
A versatile, adaptable and efficient power and control circuit is thus provided in accordance with the stated objects of the invention, and while the specifics of the circuit have been defined in great detail, various changes and modifications of the circuit involving interconnections between the integrated circuits, U1, U2 and the pulse width modulator 21, addition of noise suppression capacitors or resistance value changes may become apparent to those skilled in the art. These and other changes and modifications may be made without departing from the spirit of the invention or from the scope of the appended claims. | This invention discloses a versatile power and control circuit for an electric door strike that is operable in four different modes with readily adjustable release times. In addition, the invention is directed toward the provision of a highly efficient power supply that permits miniaturization and prevents overheating in the confined space that is available for installation in a door jamb. | 4 |
FIELD OF THE INVENTION
This invention relates to charge coupled device (CCD) technology, and more particularly to charge coupled semiconductor structures for use in image and/or dynamic storage applications.
DESCRIPTION OF THE PRIOR ART
Charge coupled devices have become well known in the prior art. There is continued investigation of CCD's for use in slow scan TV cameras, document readings, and other high sensitivity imaging applications. CCD's are also under investigation and study for use in memory systems and for shift register applications. Even though the CCD concept is relatively new, it is under continuous study and development for application in a large number of areas.
Charge coupled devices are basically metal-insulator-semiconductor devices which belong to a general class of structures which store and transfer information in the form of electrical charge. The charge-coupled device has been distinguished by the property that the semiconductor portion of devices is substantially homogenously doped, with regions of different conductivity being required only for injecting or extracting charges. A typical semiconductor charge-coupled device shift register is described, for example, in Boyle et al., Bell System Technical Journal, 49, 587, 1970. Basically, the CCD comprises a structure wherein a plurality of metal electrodes are disposed in a row over an insulator (dielectric) which in turn overlies and is contiguous with the surface of a semiconductor body. Sequential application of voltages to the metal electrodes induces potential wells adjacent the surface of the semiconductor body in which packets of excess minority carriers can be stored and between which these packets can be transferred. To insure composite directionality of charge packet transfer, the transfer potential well must be asymmetrical at least during the transfer operation. As discussed by W. S. Boyle and G. S. Smith in an article entitled "Charge Coupled Semiconductor Devices" B.S.T.J. April, 1970, pages 587-593, it was considered that at least three phase clock pulses are required to provide the requisite asymmetry for a uniform dielectric thickness under the gate electrode and a homogeneous semiconductor.
However, the three phase system suffers from the disadvantage of long bit lengths as defined by the accumulative width of the electrodes together with the spacing therebetween and a complex clocking requirement.
A two-phase CCD has the advantage of simpler clocking requirements and is generally fabricated by the use of overlapping gate electrodes and/or non-uniform dielectric thicknesses under the gate or transfer electrodes so that appropriately asymmetrical potential can be formed whenever a voltage is applied to any gate electrode. In any event, as in the three phase configuration, the bit length is defined by the accmulative width of the electrodes and the spacing therebetween. As is obvious, and reduction in the bit length of a CCD structure would permit greater densification of devices in an integrated structure and also improve the data transfer rate.
Also, charge coupled devices have been described for adaptation to the fabrication of an imaging array where for example a parallel readout of the array is first made to adjacent shift register with serial readout thereof to a sensing circuit. Typical imaging arrays are disclosed and described in U.S. Pat. Nos. 3,781,574 and 3,826,296 which employs a parallel readout of all active sensor elements in a row to a shift register stage with subsequent serial readout to the edge of the array where each charge packet is then transferred to a column transfer line and serial CCD shift register coupled to a simple readout circuit. Also, to increase the speed of the readout from the imaging array and minimize smearing of detected images, M. F. Tompsett et al. describe in an article entitled "Charge-Coupling Improves Its Image, Challenging Video Camera Tubes", on pages 162-169, Electronics, Jan. 18, 1973, another concept of information transfer from a scan area image into some bulk memory. One of these approaches is called a line-address scheme and the other is the frame-transfer scheme. In the frame-transfer scheme, the image area is distinct from the storage area, whereas in the line-address scheme, the image and storage areas are one and the same. The line-address approach affords almost half the chip size and resultant advantages such as better yields and cost reductions. In the line-address approach, in reported literature, an area image is first integrated for a time period, T 1 , in the image area. At the end of the integration period, data transfer period, T 2 , begins. During the transfer period, each line of the imaging area and storage area is transferred to a linear shift register at one end of the image/storage area and then transferred out to the output circuit to a bulk memory. For reducing image smearing to negligible proportions, the image integration period must be much greater, practically about 100 times, than that of the data transfer period. A reduction in the transfer period obviously affords a proportionate reduction in integration time. Accordingly, any reduction in the transfer of data from the imaging array would provide enhanced operation thereof.
SUMMARY OF THE INVENTION
Generally, the invention comprehends the fabrication of a charge coupled device incorporating in the body regions of a semiconductor substrate regions of different concentration of the same conductivity determining impurity or dopant in correlation with superposed phase electrodes which enables the compaction of the electrodes together with substantially zero spacing (e.g. 2,000 Angstroms) therebetween and the created asymmetrical depletion regions formed under them. Enhanced operation of the structure of this invention is affected by segmentation thereof with discrete or independent reading of information in each segmented portion of the CCD channel. This may be effected by physical segmentation of the CCD channel into sub-units, or by inducing flow of information in opposite directions from a predetermined point in the CCD channel with appropriate sensing of information at the distal downstream cells of the unit.
Accordingly, it is an object of this invention to provide a semiconductor device containing an improved charge-coupled array.
It is another object of this invention to provide a charge-coupled array which uses a semiconductor body having different doping levels therein aligned to the phase electrodes.
It is a further object of this invention to provide a high density charge-coupled array which has, by virtue of the short bit length, a high data transfer rate.
It is still another object of this invention to describe the process for producing this improved semi-conductor device.
The foregoing and other objects, features and advantages of this invention will be apparent from the following more particular description of preferred embodiments of the invention as illustrated in the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIGS. 1-8 are schematic cross-sectional views illustrating various stages in the fabrication of a CCD array in accordance with this invention.
FIGS. 8A and 8B depict waveforms illustrating the operation of the CCD array shown in FIG. 8.
FIG. 9 is a schematic cross-sectional view illustrating another embodiment in accordance with this invention.
FIGS. 10-10B are simplified drawings of the electrode structure and operation of a prior art CCD array.
FIGS. 11-11B are simplified electrode configurations and phase operation thereof in accordance with another embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Although this invention will be described in conjunction with a charge coupled device structure fabricated in a monocrystalline semiconductor substrate of silicon, it is to be understood that any semiconductor material may be used for the fabrication of CCD devices in accordance with this invention which is capable of supporting surface charges of the type required in charge coupled structures. It should also be understood that the drawings employed herein are used to merely illustrate the invention and accordingly are not drawn to scale but rather designed merely to illustrate the principle of the invention by depicting only a small portion of a semiconductor substrate or chip which may be on the order of 200 by 200 mils.
As shown in the drawings, fabrication begins with a monocrystalline silicon substrate 1 on which is sequentially formed a thin, thermal oxide layer 2 of about 2,000 Angstroms and an overlying layer 3 of a pyrolytically deposited silicon oxide layer of about 8,000 Angstroms.
It should be noted and recognized that while a P-type semiconductor substrate is shown and described by way of example, an N-type semiconductor or semi-insulating mediums are also equally adaptable to the principles of the invention. Accordingly, it is to be understood that opposite type conductivity materials, as well as other insulation such as silicon nitride alone or in conjunction with silicon dioxide in composite form can also be utilized.
Further, it is to be understood that the fabrication of CCD devices in accordance with this invention employs conventional semiconductor fabrication techniques which are varied and well known in the art and consequently form no part of the present invention.
After formation of the thermal and pyrolytic oxide layers 2 and 3, the structure is overcoated with a suitable photoresist which is exposed and developed to provide a resist mask 4 defining a suitable opening for etching through the thermal and pyrolytic oxide layers 2 and 3 to bare a portion 5 of the top surface of semiconductor substrate 1.
In the next operation, a thin thermal oxide layer 6 of about 300 Angstroms is grown on the substrate surface 5 to serve as a screen for ion implantation. The second layer of a photoresist 8 is deposited over the structure, inclusive of the thin oxide layer 6 with suitable exposure and development to form windows 7. The substrate or wafer 1 is then ion implanted with an impurity determining ion such as boron through the exposed portion of screen oxide layer 6 to form doped regions 9, the remainder of the ions being captured by photoresist layer 8. Typically, the thickness of region 9 will be about 2000 Angstroms, with the surface concentration about five times the concentration of P-substrate. As indicated, a typical impurity to be ion implanted is boron resulting in regions 9 having a P-type impurity concentration higher than the bulk of silicon substrate 1.
The formation of the ion implanted regions 9 is followed by stripping of the photoresist 8 and etching away of the screen oxide layer 6. This is followed by growth of a thin thermal oxide layer 10 of about 300 Angstroms over the exposed silicon substrate. In the next operation, the silicon oxide layer 10 is covered with a silicon nitride layer 10A of about 300 Angstroms in accordance with well known and conventional chemical vapor deposition techniques. In the next operation, a polycrystalline silicon layer 11 of about 7,000 Angstroms heavily doped with N-type impurities is formed over the entire surface in a manner well known in the semiconductor art.
Windows 12 are next formed in the polycrystalline layer 11 by first depositing a layer 13 of pyrolytic silicon dioxide with a thickness of about 1,000 Angstroms over the top surface of the polycrystalline silicon 11. Selected portions of the silicon dioxide layer 13 are then removed from the top surface of the polycrystalline silicon 11 using well known photolithographic techniques to leave a pattern of the silicon dioxide layer 13 defining suitable openings for access to the portions of the polysilicon layer to be removed. The exposed portion of the polycrystalline silicon layer 11 is then removed down to the thin nitride layer 10A. Next, the photoresist is stripped away and the exposed layer of the nitride layer 10A is etched, followed by the etching away of the exposed portion of the thermal oxide layer 10 and the remainder of the oxide layer 13. Suitable etchants for etching silicon nitride and silicon dioxide are hot phosphoric acid and buffered hydrofluoric acid, respectively. The N+ regions 14 and 15 are then formed in the bare portions of the semiconductor substrate 1 by standard diffusion or ion implantation techniques followed by the usual drive indiffusion step. For the described semiconductor body 1, arsenic is preferably used as a dopant to create the N+ regions 14 and 15. The surface concentration of the N+ dopant is about 5 × 10 20 atoms/cc, the final junction depth of the N+ regions being about 1 micron. It will be understood that the polysilicon is also simultaneously doped at this point with the N+ dopant. After the creation of the N+ regions 14 and 15, the exposed surfaces of substrate 1 and the polysilicon 11 are thermally oxidized to obtain a layer of silicon dioxide 15A of about 3,000 Angstroms in thickness. As will be appreciated, the dopant is driven in during the oxidation and can be further driven in in an inert atmosphere subsequent to reoxidation.
It is to be understood that the formation of doped regions 14 and 15 comprises means for injecting and detecting minority carriers in the CCD device which are well known in the art and form no part of the present invention. It is also to be understood that another method of supplying minority carriers is due to generation of whole-electron pairs by photon absorption and, accordingly, it will be appreciated that the invention described herein is comprehended for use as a line or area imaging device.
Using photoresist, a selective etching operation is now successively performed in the top oxide layer 15A and the polycrystalline silicon layer 11 to define polycrystalline silicon electrodes 11A. This is followed by subjecting the unit to thermal oxidation to form layers 16 of silicon dioxide around the sides and the top of the polycrystalline silicon electrodes 11A. As will be appreciated, no oxide is grown or formed on the exposed portions of the thin silicon nitride layers 10A.
A further photoresist layer 19 is formed over the structure and suitably developed in the configuration shown in FIG. 7 for ion implantation of regions 17 in a continuation from the ion implanted regions 9 with slight overlap at portion 18. The ion implanted region 17 is sufficiently doped with an ion of the same conductivity determining type as region 9 but in higher concentration normally about five times higher than that of region 9 with about the same depth as region 9.
After the last ion implantation step, the photoresist layer 19 is removed and a new photoresist layer 21 is applied for the formation of the contact 22. Electrode 23 of a conductive aluminum/silicon composition in a thickness of about 1 micron is obtained by depositing the aluminum/silicon composition by conventional evaporation techniques used in metallizing integrated circuits. The specific electrode configuration or pattern is defined on the aluminum/silicon by photolithographic masking and etching processes. An indicated previously, this involves applying a photoresist to the surface, exposing the photoresist to light through a mask of the pattern desired, and then developing the photoresist. The portion of the aluminum/silicon layer not protected by the photoresist pattern is removed with a suitable etchant.
As will be appreciated for imaging applications, the field or transfer electrode 23 must be at least semitransparent (ideally 100% transparent), and accordingly may be fabricated by use of very thin layers of chromium, nichrome, and/or gold of about 100 Angstroms in total thickness. It may be also expected that indium oxide, layers of which exhibit very high optical transmission coefficients, may also be used typically in a thickness of about 0.5 microns (5,000 Angstroms).
A portion of the final structure is shown in FIG. 8 with its operation illustrated by depletion or potential profiles of FIGS. 8A and 8B.
FIG. 9 illustrates another embodiment of this invention in which the above CCD structures (as well as heretofore conventional structures) can be segmented into sub-channels where data can be inputted at terminals 22A and 22B and sensed at each of output terminals 25A and 25B. As will be appreciated, when the CCD structures are adapted for imaging applications, plural portions of the information can be shifted towards output terminals 25A and 25B reducing the time for transferring of information. The segmentation on the CCD channel is formed by formation of a heavily doped P++ region 26 by conventional photolithographic techniques at any appropriate point in the fabrication of the device. These P-type diffusions are known as channel stops which create potential barriers at an intermediate point of the CCD channel as illustrated schematically in FIG. 9. As will be understood, the purpose of the channel stop diffusion is to prevent flow of charge from one portion of the channel to the succeeding portion of the channel. The impurity concentration of the P-type channel stop diffusion should be sufficiently high (e.g. about two or three orders of magnitude higher than the substrate impurity concentration to a depth of about 5,000 Angstroms) so that the voltage of transfer electrodes 11A and 23 which pass over the diffusions will cause substantially no depletion to occur and therefore effective potential barriers will be obtained where desired.
It may be noted with respect to the CCD devices in accordance with this invention that, for a given state of the art in photolithography, width W and spacing S being the minimum allowable width and spacing for polysilicon thin film patterns, the above process will provide a bit length of about W + S. For example, a state of the art provides the attainment of W of about 0.2 mils and spacings of about 0.15 mils, then the above process provides a bit length of about 0.35 mils.
Also, the invention provides a CCD structure amenable to simple two-phase clocking or uni-phase clocking where one-phase is dc. For two-phase clocking, the phase identified as phase 1 must have voltage amplitudes higher than phase 2 inasmuch as substrate surface under phase 1 gates is heavier in doping compared to phase 2 areas. Directionality required in two-phase or uni-phase clocking is provided by the proposed structure through unequal doping of the substrate surface (i.e., regions 9 and 17 under phase 1 electrodes and regions 17 and 20 under phase 2 electrodes). It is also to be understood that although the process as described above will yield surface channel operation of charge coupled devices, a buried channel operation can be readily obtained through a 1-3 micron layer of N doping on the P - substrate. Also, the structures are characterized with self-aligned FET type circuitry whose simultaneous fabrication is directly provided by the described process.
FIG. 11 illustrates another embodiment of this invention in which multi-directional bit flow can be induced in a CCD channel, with operational comparison illustrated with respect to conventional electrode phase operation illustrated in FIG. 10. Although any electrode configuration can be employed, the multi-directional induced bit flow is illustrated with respect to electrodes 32X to 32N and 31X to 31N. In the specific form shown, the charge storage electrodes comprise electrode pairs with each pair including a polysilicon electrode such as 31 which is spaced, in a stepped manner, relatively close to a semiconductor substrate and a metal electrode 32, as of aluminum, which is also spaced in a stepped manner close to the substrate. This pair of electrodes is driven by the same voltage phases such as phase 1, and the other adjacent pairs by phase 2 which form an asymmetrical potential well in a substrate for storage and shifting of charges in conjunction with voltage phase 2. The conventional configuration of electrodes and their connection to a source of phase clock pulses is shown in FIG. 10 in conjunction with potential or depletion profiles of FIGS. 10A and 10B. The invention as illustrated in FIG. 11 comprehends a substantially identical configuration of electrodes concentrically configured about an intermediate point 35 of the CCD channel into concentric groups 30 and 31 with the utilization of one of electrodes 32 as a control electrode 3A so as to induce bit flow in a channel in opposite directions away from the intermediate point 35. The depletion or potential profiles of the operation of the structure of FIG. 11 is shown in FIGS. 11A and 11B.
It is to be understood that while the invention has been particularly shown and described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. | A semiconductor integrated charge coupled device is disclosed having an optimized minimum bit length for two-phase operation. Minimum spacing between created depletion regions and electrodes is obtained by having different ion implanted doping levels in the structure in correlation to overlying phase electrodes.
Also disclosed is means for segmenting a charge coupled device channel with provision for sensing of data in each channel segment to increase the speed of transfer of information from the device.
Also disclosed is a novel correlation of transfer or control electrodes of a CCD device with a source of phase clock pulses to provide directionality in a single CCD channel. | 7 |
RESERVATION OF COPYRIGHT
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office patent file or records, as it becomes available to the public, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to engines and, particularly, to a small engine fuel injection system.
2. Description of Related Art
Small single and twin cylinder engines fueled by propane are in common use in such applications as floor buffing, commercial carpet cleaning and the like. Propane is used in these applications since it is inherently cleaner burning than gasoline, especially in an area of carbon monoxide exhaust emissions.
In such small engines, the propane fuel is typically metered to the engine either by a Venturi mixer or a variation of that principle, a spudded carburetor. Such systems are highly affected by small variations such as air cleaner restriction, regulator pressure drift, or fuel hose restriction. In addition these systems do not provide a consistent and predictable air/fuel mixture throughout the entire range of operating conditions. In addition, such systems do not allow for any monitoring of fuel system operation. Deteriorated engine tune, fuel composition deviation, altitude, or other conditions which could lead to undesirably high levels of CO (carbon monoxide) emission.
Closed loop fuel controls for large engines, in which feedback is provided concerning the actual air/fuel calibration, particularly for engines in motor vehicles, are known. In such modern fuel-injected engines, the primary input used to determine the amount of fuel required by the engine (i.e., determination of the pulse width for the fuel injectors) is a "speed density" reading. This is calculated using engine RPM (revolutions per minute) and the manifold absolute pressure (MAP) sensor voltage. The manifold absolute sensor voltage is a signal indicative of engine manifold pressure during intake and compression. In more advanced engines, additional sensor inputs such as intake air temperature, engine coolant temperature, and the like are used, but RPM and MAP are the principal inputs. In a multi-cylinder engine, the MAP voltage signal is fairly constant and thus is readily detectable, since the individual cylinder firings average out. For example, in an 8 cylinder engine, as illustrated in FIG. 1a, the MAP voltage signal is virtually a straight line, assuming constant throttle and engine load settings.
However, as can be seen in FIG. 1b, in single cylinder engines there is considerable pulsation and variation in the MAP voltage signal. Such extreme variation makes calculation of the proper fuel injector pulse width very difficult. One approach which has been attempted is to take the minimum and the maximum MAP voltages and average them to obtain a value to calculate fuel flow. However, this approach is suboptimal in achieving the proper fuel ratios.
Accordingly, there is a need for a closed loop fuel control system for small single and twin cylinder engines. There is similarly a need for a closed loop fuel injection system for a single cylinder engine which employs the MAP signal to achieve proper fuel ratio control.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention is obtained when the following detailed description is considered in conjunction with the following drawings in which:
FIGS. 1a and 1b are diagrams of MAP signal voltage versus crankshaft rotation from the preceding intake cycle;
FIG. 2 is a diagram of the use of MAP signal voltage to determine correct fuel injector pulsing according to an embodiment of the present invention;
FIG. 3 is a block diagram illustrating a fuel injection system according to an embodiment of the present invention;
FIG. 4 is a more detailed block diagram illustrating a carburetor and cylinder for use in a fuel injection system according to the embodiment of FIG. 3;
FIG. 5 is a block diagram of a fuel injection controller according to the embodiment of FIG. 3;
FIG. 6 is a flow chart illustrating a method for fuel injection according to the embodiment of FIG. 3; and
FIG. 7 is a flow chart illustrating a method for fuel injection according to the embodiment of FIG. 3.
SUMMARY OF THE INVENTION
These and other problems in the prior art are overcome in large part by a small engine fuel injection system according to the present invention. A method according to one embodiment of the present invention employs the minimum MAP voltage signal to calculate the pulse width for a fuel injector. More particularly, a fuel injection system according to an embodiment of the present invention uses the RPM and MAP sensor inputs to calculate the amount of fuel required for the next spark firing. A pulse width modulated solenoid is provided which receives fuel vapor and injects fuel into the throttle body.
During the intake stroke, cylinder suction causes the pressure in the intake manifold to drop and reach a minimum. This minimum approximates the cylinder pressure when the valve is closed and thus is directly related to the amount of air in the cylinder. A controller for the fuel injector system samples the MAP sensor voltage between the firings. This minimum MAP value is compared to the minimum from the previous firing to identify compression spark firing or waste spark firing. By comparing the two minima, the controller identifies the correct pressure value and synchronizes the fuel delivery to the correct spark.
A look-up table having RPM and MAP voltages as inputs is provided to determine the correct fuel injector pulse widths. A correction table stores values to compensate for performance variations. Finally, a gain correction is provided to compensate for engine variations.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the drawings and with particular attention to FIG. 2, a schematic showing use of the MAP signal and spark firing relative to fuel injector pulsing is shown. The schematic 1000 includes the MAP signal voltage 1001 versus crankshaft rotation. The MAP signal voltage 1001 has minima 1004, 1006. The MAP signal voltage also has a relatively steady state value 1002. The MAP signal voltage 1001 has minima at 1004, 1006 due to the intake stroke. More particularly, during the intake stroke, the cylinder suction causes the pressure in the intake manifold to drop and reach the minimum value. The minima 1004, 1006 approximate the cylinder pressure when the valve is closed and thus directly relate to the amount of air and fuel in the cylinder. Compression or ignition spark firings 1010a, 1010b normally occur after the dip in the manifold pressure (i.e., after the minima 1004, 1006). By contrast, the waste spark firings 1008a, 1008b occur at the steady state manifold pressure 1002. By detecting the minima 1004, 1006, the fuel injector system identifies the correct pressure value synchronizing the fuel delivery to the correct spark. Thus, after the ignition sparks 1010a, 1010b, fuel injector pulses 1012a and 1012b are provided, respectively.
As will be described in greater detail below, a fuel injection controller 102 (FIG. 3) in a system according to one embodiment of the present invention samples the MAP sensor voltage from two milliseconds after every firing until the next firing at a 2 KHZ rate. The fuel injection controller 102 adds four samples in sequence and compares them to the next four saving the minimum. The minimum MAP sensor voltage value is then compared to the minimum from the previous firing to identify the compression spark firing or waste spark firing. By comparing the two minima, the fuel injection controller 102 synchronizes the fuel pulses and uses the correct pressure value to compute the necessary amount of fuel in a look-ahead fashion (i.e., the fuel need from a look-up table is determined the previous cycle; correction is provided for load changes, based on the MAP voltage, as will be discussed in greater detail below).
When a compression minimum is detected, the fuel injection controller 102 accesses a fuel look-up table (not shown) to determine the width of the subsequent fuel pulse. As part of this process, as will be described in greater detail below, the fuel injection controller 102 uses the RPM and minimum MAP value to calculate the amount of fuel which is to be provided. An analog circuit converts the received magneto primary coil voltage, which is representative of the engine RPM, to a 5 V square wave. The resulting clean and conditioned square wave is then sent to the fuel injection controller for timing measurements.
The correct pulse width can be determined through interpretation of the actual MAP pressure and the RPM. More particularly, the fuel look-up table of pulse width values is stored in processor-accessible memory. Nine values of MAP and four RPM values, defining 36 cells, are used. Each cell corresponds to a fuel injector pulse width. If the MAP and RPM measured values do not correspond to their tabular coordinates, interpolation may be used. It is noted that greater or fewer than nine MAP values and four RPM values may be employed.
In addition, the fuel injection controller 102 uses an oxygen sensor 110 input to determine whether the air/fuel ratio in the exhaust is richer or leaner than stoichiometry and provides a correction, stored in an integrator register (not shown), to the values in the fuel look-up table. The value in the integrator register is centered at 128, which corresponds to no correction. In one embodiment, the total control range is plus or minus 25%. The oxygen sensor 110 voltage is sampled after every firing. If the oxygen sensor 110 voltage corresponds to lean, the fuel injection controller 102 increments the value in the integrator register and if the oxygen sensor voltage corresponds to rich, decrements the value in the integrator register. The integrator value is multiplied with the output from the fuel look-up table, thereby increasing or decreasing fuel injector pulse width. The entire table (i.e., each cell) is updated by this integrator value. This type of continuous update causes the air/fuel ratio to hover around very close to the desired stoichiometric air/fuel ratio.
In addition to the integrator register, a correction table is used to correct individual values in the look-up table. The correction table is similar to having a separate integrator value for each cell of the fuel look-up table. If the operating point of the integrator register is away from center by a predetermined amount, the cell in the fuel look-up table closest to the working conditions will be corrected to the "actual" value (i.e., shifted by the integrator amount) and stored in the correction table, thus reshaping the fuel pulse width to the particular engine and hardware. The values in the correction table are stored in EEPROM for more correct tables in future operations.
In addition to the integrator register and correction table, a fuel map gain correction is provided. The fuel map gain correction is another correction factor, but one which modifies the entire fuel look-up table. The fuel map gain correction is used to compensate for fuel look-up table "drift," which can result if the entire table has drifted from its predetermined settings. More particularly, if the total sum of shifts in the correction table is larger than a predetermined amount, the entire fuel look-up table will be updated by the gain correction factor. In one embodiment, the threshold sum of shifts is 10.
Turning now to FIG. 3, a block diagram illustrating a fuel injection system 100 including a fuel injection controller 102 according to the present invention is shown. The fuel injection system 100 includes a controller 102 which is configured to receive inputs from a 12-volt battery (not shown), a primary signal from the magneto (not shown) as well as having a ground input. In addition, the fuel injection controller 102 is configured is receive an input from an oxygen sensor 110 positioned within an exhaust manifold 112 of the engine. A vacuum hose 120 connects the fuel injection controller 102 to the carburetor 116. The vacuum hose 120 provides the MAP input to the fuel injection controller. A muffler is coupled to the exhaust manifold. A propane tank 128 provides fuel for the carburetor 116.
More particularly, the fuel injection controller 102 controls an electric shut-off valve 126 or fuel lock-off solenoid. When zero RPM are detected, the fuel injection controller 102 causes the fuel to turn off by controlling the ground to the solenoid. A fuel pressure regulator 124 is also provided to regulate (i.e., maintain consistent pressure) the flow of fuel to a fuel injector 122. The fuel injector 122 includes a pulse width modulated solenoid with a peak-and-hold driver (not shown). The fuel injector 122 is coupled to a fuel inlet pipe 118 to direct the fuel to a carburetor 116. An air cleaner 114 is further coupled to the carburetor 116. The engine 104 is provided with one or more spark plugs 106. As will be discussed in greater detail below, the fuel injection controller 102 is configured to determine pressure within the engine manifold 104 and cause the fuel injector 122 to inject fuel from the propane tank 128 at appropriate intervals and pulse width. As will be discussed in greater detail below, the fuel injection controller 102 is configured to deliver one fuel pulse for every two revolutions of the engine.
The fuel injection controller 102 is further provided with a "SNIP loop", which is essentially a switch activatable by a user, for example. Activation of the SNIP loop allows a user to deactivate an engine shut-off feature. More particularly, the fuel injection controller 102 is configured to shut off the engine if the reading from the oxygen sensor indicates that the engine has been running rich for a programmable predetermined period. In addition, the fuel injection controller 102 is configured to shut off the engine if the vacuum hose is not connected and the MAP reading is relatively steady. Activation of the SNIP loop (e.g., by cutting a wire) causes this feature to be deactivated.
A more detailed diagram of the fuel injection system of FIG. 3 is illustrated in FIG. 4. The vacuum hose 120 is provided from the carburetor 116 to the fuel injection controller 102. The vacuum hose 120 delivers the intake pressure to the MAP sensor in the fuel injection controller 102 as will be described in greater detail below. As shown, air is provided from the air cleaner 114 via a duct 130 into a air/fuel chamber 132. The fuel/air chamber 132 receives fuel from the fuel inlet pipe 118. A valve 134 regulates the introduction of the air/fuel mixture into the intake 135 and the cylinder 137.
Turning now to FIG. 5, a block diagram of the fuel injection controller 102 is shown. At the heart of the fuel injection controller 102 is a control processor 300. The control processor 300 may be any of a variety of commonly available 8, 16, or 32-bit microprocessors or microcontrollers such as the Motorola HC05 or the Microchip 16 C xx processors. The control processor 300 includes an internal EPROM (not shown) used to store the fuel look-up table. The control processor 300 is coupled to an electrically erasable programmable read-only memory (EEPROM) 302, which is used to store look-up and correction tables for determining the width of fuel injection pulses. The control processor 300 is further configured to receive the SNIP loop input for de-activating the shut-off process discussed above. When the SHIP loop feature has been deactivated, the shut-off conditions merely cause the engine check light to light up.
The fuel injection controller 102 is configured to receive an engine vacuum reading from the vacuum hose 120 (FIG. 3). The engine vacuum reading is provided to the MAP sensor 304 which converts the pressure reading to an output voltage. The MAP sensor 304, in turn, provides the resulting MAP voltage signal to a scaling and calibrating amplifier 306, which provides a signal to the control processor 300. As discussed above, the control processor 300 uses the MAP voltage signal to distinguish the compression spark from the waste spark and causes the fuel to pulse a predetermined time after detection (e.g., 3 milliseconds). The control processor 300 thus synchronizes the fuel pulse to the compression spark. As will be discussed in greater detail below, the MAP voltage is further used as an input to a fuel look-up table stored in EEPROM 302 (and transferred to RAM on start-up) used to achieve the appropriate stoichiometric air-to-fuel ratio.
The control processor 300 is further coupled to receive a battery voltage signal. The battery voltage is used to open the fuel injector 122. Different voltages will vary the time required to open the injector and thus affect pulse width (i.e., pulse width varies inversely with battery voltage). The control processor 300 compensates for different (10-14 V) battery voltages by increasing or decreasing pulse width based on the detected voltage.
The control processor 300 is further coupled to an engine check light output 316 which is configured to be ON when the RPM signal is off. Further, an injector driver 318 is provided for driving the fuel injector 122, and a safety circuit 312 and solenoid driver 314 are provided for activating the safety shut-off valve 126. The safety circuit 312 is configured to cause the safety shut-off valve 126 to close when there is no RPM signal and when the control processor 300 has not enabled fuel flow.
The control processor 300 is further configured to receive a magneto input (i.e., the RPM or tachometer reading) via a signal conditioning circuit 310 which provides the tachometer signal to the control processor 300 and the safety circuit 312. The signal conditioning circuit 310 is provided to filter noise and ringing, so as to ensure a single 5 V pulse per spark. The fuel injection controller is configured to deliver one fuel pulse every two revolutions of the engine, three milliseconds after the control processor 300 and in one embodiment uses a peak-and-hold scheme to drive the fuel injector 122. While a saturated coil-type driver could be used, the peak-and-hold scheme is superior with respect to faster opening and closing times and heat build-up in the injector coil. More particularly, at the initiation of the fuel pulse, full battery voltage is applied to the fuel injector 122, until current reaches 2.4 amperes. After this peak current has been reached, the current is dropped back to 0.75 amperes to hold the injector open. Finally, a "kick-back" clamp at 25 V and 0.1 ms voltage use time protects the injector driver 318 and minimizes radio frequency interference.
The control processor 300 receives the oxygen sensor signal via a filter 308, which is provided for signal conditioning. The oxygen sensor signal produces a high voltage (˜0.6-0.9 V) when the air/fuel ratio is rich and a low voltage (˜0.2 V) when the air/fuel ratio is lean. The control processor 300 tries to maintain a stoichiometric air/fuel ratio by varying the fuel pulse width. The fuel pulse width is derived from a fuel table stored in control processor's internal memory EPROM, which is transferred to RAM during use.
The EEPROM 302 stores the correction table which has 36 cells (i.e., nine MAP values by four RPM values which are loaded at start-up). Each fuel look-up table value corresponds to a fuel injector pulse width. Thus, if the reading of the MAP value and the RPM value fall within a particular range, the fuel injector will be driven at a particular pulse width as defined by the value in the fuel look-up table.
The signal from the oxygen sensor 110 is used to provide a correction to the table value. More particularly, the oxygen sensor voltage is sampled after every spark firing (i.e., waste and compression) The oxygen sensor voltage corresponds to a low air/fuel ratio (i.e., less than 0.2 volts) if the engine is running lean and a high voltage (i.e., 0.6 to 0.9 volts) if the engine is running rich. The control processor 300 is provided with an internal register referred to as the "integrator register." The integrator register stores a value centered at 128. The integrator register value is incremented if the engine is running lean and decremented if the engine is running rich. The value from the integrator register is multiplied with the values in the fuel look-up table such that the fuel level is adjusted depending on whether the engine is running lean or rich (i.e., pulse width is decreased if the engine is running rich and increased if the engine is running lean).
The EEPROM 302 further stores a correction table used to provide "local" correction. The correction table is employed when the fuel table output at a particular RPM and MAP is off-center by more than three integrator counts (i.e., if the integrator register value is less than 126 or greater than 131). In that case, the entry in the fuel look-up table at that particular cell is adjusted so as to try to maintain the integrator register value at center. The values of the correction table are stored in the EEPROM 302 for use after the battery voltage has been removed and applied again.
Finally, a fuel map gain correction factor is used to provide an overall correction to each value in the look-up table if the total from all correction table shifts is richer by 10 counts or more from center. In this case, the gain correction factor will increase. Thus, an overall offset for the fuel table may be corrected by use of the fuel map gain correction factor. Value maintenance for this function is stored in the EEPROM.
Turning now to FIG. 6, a flow chart illustrating operation of an embodiment of the present invention is shown. More particularly, in a step 602, the control processor 300 receives the magneto signal via the signal conditioning unit 310. The magneto or RPM signal indicates when a spark has fired. Upon firing of the sparks, the control processor 300 samples the MAP sensor voltage in a step 604. As discussed above, the MAP sensor is provided to receive the engine vacuum signal into the MAP sensor 304 which then provides the signal to the calibrating and scaling amplifier 306 and then to the control processor 300.
The control processor 300 then stores the minimum value of the samples in a step 606. The newly sampled minimum is then compared with a previously stored minimum in a step 608. If the new minimum is greater than the previous minimum, then in a step 610, the control processor 300 determines that a compression firing has occurred and, in a step 614, pulses the fuel injector. If, however, in step 610 the control processor 300 had determined that the new minimum was not greater than the previous minimum, then the control processor 300 will replace the previous minimum with the new minimum, and will continue sampling.
As discussed above, the control processor 300 uses the MAP sensor voltage to synchronize the pulse firings with the compression spark. The MAP sensor voltage, the RPM level and an oxygen sensor input, as well as a battery voltage input, are also used to determine a width of the fuel injector pulse. More particularly, turning now to FIG. 7, a flowchart 700 illustrating the use of the above-mentioned inputs and a fuel look-up table in order to determine fuel injector pulse width is shown. In a step 702, the control processor 300 reads the battery voltage, which is used to open the fuel injector (i.e., pulse the solenoid). As noted above, too high a battery voltage can result in too short a pulse; too low a battery voltage can result in too long a pulse. Accordingly, the control processor 300 adjusts the fuel pulse width to compensate for differing battery voltages, in a step 704.
After start-up, the control processor 300 further reads the RPM level from the magneto and signal conditioning unit 310, and the MAP voltage level from the MAP sensor 304. More particularly, the control processor 300 identifies a start-up condition from key on until about 1000 RPM, during which the pulse is wider than at other times.
Then, the RPM level and the MAP voltage are used to determine the fuel injector pulse width. More particularly, after the first fuel injection pulse, the length or duration of each subsequent pulse is increased until a maximum is reached. Thereafter, the succeeding pulses are narrowed until the minimum is reached again and the process is repeated. This sweep cycling continues until an RPM of greater than 1000 is detected, indicating that the engine has started. This permits fast and reliable start up under varying conditions. Once the RPM level and MAP voltage level have been read, the control processor 300 accesses the fuel look-up table, in a step 708, for the appropriate pre-set fuel injector pulse width. The oxygen level in the engine is read in a step 710. The control processor 300 determines whether the engine is running rich or lean in a step 712. If the oxygen level indicates that the engine is running rich, the integrator register value is decremented, in a step 716. However, if the reading from the oxygen sensor indicates that the engine is running too lean, the integrator register value is incremented in a step 714. The resulting adjustments in the integrator register are applied to each cell in the look-up table, in a step 718. The processor then determines whether or not the value in the integrator register is off-center by more than 3 integrator counts, in a step 720. If the value in the integrator register is off-center, then the current cell is adjusted, with the update being stored in the correction table, in a step 722. The control processor 300 then sums the number of counts by which all the cells in the correction table are off-center in a step 724. If, in a step 726, the summation indicates that the total difference between the correction table shifts and the fuel look-up table is more than a predetermined number or threshold (for example, 10), then the control processor 300 shifts the entire table in a step 728. Finally, the appropriate cell value from the look-up table is applied to pulse the fuel injector, in a step 730.
The invention described in the above detailed description is not intended to be limited to the specific form set forth herein, but is intended to cover such alternatives, modifications and equivalents as can reasonably be included within the spirit and scope of the appended claims. | A fuel injection system for small engines. A controller is provided to monitor manifold absolute pressure, engine RPM and engine oxygen levels. Fuel injector pulses are synchronized to minima in the manifold absolute pressure signal. The width of the pulses is varied depending upon the manifold absolute pressure, the engine RPM, and the oxygen level. In addition, a plurality of correction factors are available to adjust the pulse width depending on engine performance. | 5 |
FIELD OF THE INVENTION
The present invention is generally directed to a compact disc holder and, more particularly, a compact disc holder having first and second disc supporting surfaces.
BACKGROUND OF THE INVENTION
In recent years, it is well recognized that compact discs have come into wide spread use for a variety of different purposes. They are typically of a standard diameter and thickness and are used to a significant extent for computer programs and data, and for use with so-called "multi-media" equipment. In these applications, compact discs are being used to an ever expanding degree due to the amount of program and data information that can be stored thereon.
Of course, compact discs are recognized as having many other uses that are equally well known. Perhaps the best known use is as a medium for recording and replaying music, although compact discs are also widely used for digitally recording visible subject matter such as photographs and the like. For all such uses, there is a need to be able to store compact discs in a manner that will protect them from damage.
In connection with the problem of storage, it is not uncommon for compact discs to be acquired by a consumer on a one-at-a-time or few-at-a-time basis. It is also the case that, as compact discs are increasingly coming into use for such a wide variety of different applications, there is a need to be able to effectively store compact discs in a highly organized and protected manner, particularly since compact discs tend to be expensive and oftentimes are quite difficult to replace. For these reasons, there has been a significant need for an organized, expansible, inexpensive system for facilitating the storage and retrieval of compact discs.
In recent years, and cognizant of the growing need, there have been a vast number of different proposals for storing compact discs. Unfortunately, they all have numerous drawbacks inasmuch as they are typically either complicated and expensive to manufacture, or they do not adequately function to store compact discs in a protected but organized fashion. As a result, it is recognized that there has remained a significant need for a compact disc holder that is entirely satisfactory in every respect.
The present invention is directed to overcoming one or more of the foregoing problems and achieving one or more of the resulting objects.
SUMMARY OF THE INVENTION
It is a principal object of the present invention to provide a compact disc holder that can be inexpensively manufactured. It is a further object of the present invention to provide a compact disc holder that has first and second opposed disc-supporting surfaces. It is an additional object of the present invention to provide a compact disc holder that supports compact discs in superposed relation.
Accordingly, the present invention is directed to a compact disc holder comprising a single thickness panel having a first surface and a second surface opposite the first surface. The first surface has first retention means for releasably retaining a compact disc and the second surface has second retention means for releasably retaining a compact disc. With this arrangement, the compact disc holder contemplates the retention means being disposed on the first and second surfaces to support compact discs in superposed relation.
In the exemplary embodiment, the single thickness panel is formed of thermoformed plastic having a single thickness sufficient to be flexible but self-supporting. It is also advantageous for the first and second retention means to each comprise positive projections on the first and second surfaces, respectively, which are preferably offset one from the other. In addition, the first and second retention means advantageously support compact discs on a common axis transverse to the first and second surfaces.
In the preferred embodiment, the first and second retention means each comprise a pair of circumferentially spaced retaining segments on the respective ones of the first and second surfaces that releasably retain compact discs in first and second planes that are generally parallel. The retaining segments on the respective ones of the first and second surfaces together advantageously comprise alternating positive projections and negative recesses defining superposed circular disc retention areas on each of the first and second surfaces. Also, the retaining segments on the respective ones of the first and second surfaces are advantageously positioned so as to be diametrically opposed with each of the retaining segments being formed so as to extend about the corresponding one of the circular disc retention areas by approximately 90°. Still additionally, the retaining segments on the respective ones of the first and second surfaces each preferably include a disc retaining lip which is spaced from but ramped downwardly and inwardly toward the corresponding one of the first and second surfaces.
As for the last-mentioned feature, the disc retaining lips on the respective ones of the first and second surfaces are preferably positioned so as to be diametrically opposed with each of the disc retaining lips being formed so as to extend about the corresponding one of the retaining segments by less than 90°.
As for other features, the compact disc holder preferably includes a peripheral disc supporting segment on the first and second surfaces radially adjacent each of the retaining segments which together comprise alternating positive projections and negative recesses thereby further defining the superposed circular disc retention areas. The supporting segments on the respective ones of the first and second surfaces are advantageously diametrically opposed one from the other with each of the supporting segments extending about the corresponding one of the retaining segments through an arc of approximately 90°. The compact disc holder also preferably includes a segmented disc hub support radially inwardly of each of the retaining segments on each of the first and second surfaces which together comprise alternating positive projections and negative recesses centrally disposed in each of the circular disc retention areas. With this arrangement, the disc hub supports on the respective ones of the first and second surfaces are advantageously diametrically opposed one from the other with each of the disc hub supports extending about the corresponding one of the circular disc retention areas by approximately 90°.
In a most highly preferred embodiment, the compact disc holder is suitable for use with a binder and includes a thermoformed leaf having a marginal edge for cooperation with the binder and a positively projecting hinging rib on at least one of the first and second surfaces generally adjacent the marginal edge. It is also advantageous for the marginal edge to have a plurality of holes for cooperation with the binder. Still additionally, the compact disc holder advantageously has a slot in an outermost surface of each of the retaining segments which extends generally tangential to the corresponding one of the circular disc retention areas so as to be diametrically opposed to releasably receive diagonally opposite comers of a booklet.
Other objects, advantages and features of the present invention will become apparent from a consideration of the following specification taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a compact disc holder in accordance with the present invention;
FIG. 2 is a side elevational view of the compact disc holder of FIG. 1;
FIG. 3 is a plan view of one quadrant of a compact disc retention means shown supporting a booklet; and
FIG. 4 is a cross-sectional view taken generally along the line 4--4 of FIG. 3 shown supporting a compact disc.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In the illustrations given, and with reference first to FIGS. 1 and 2, the reference numeral 10 designates generally a compact disc holder in accordance with the present invention which comprises a single thickness panel 12 having a first surface 14 and a second surface 16 opposite the first surface 14. The first surface 14 has first retention means generally designated 18 for releasably retaining a compact disc and the second surface 16 has second retention means generally designated 20 for releasably retaining a compact disc (see, also, FIGS. 3 and 4). The first and second retention means 18 and 20 are disposed on the respective surfaces 12 and 14 so as to support compact discs in superposed relation. The compact disc holder 10 is such that the single thickness panel 12 may suitably be formed of a material such as thermoformed plastic having a single thickness so as to be flexible while at the same time self-supporting (see, also, FIG. 4). As will be appreciated from FIG. 2, the compact disc holder 10 preferably is arranged such that the first and second retention means 18 and 20 support compact discs on a common axis 22 which extends transverse to the first and second surfaces 14 and 16.
Referring to FIG. 1-4, the first and second retention means 18 and 20 each will be understood to comprise positive projections 24 and 26 on the respective ones of the first and second surfaces 14 and 16 of the single thickness panel 12. The first and second retention means 18 and 20 can also be seen to be circumferentially offset in alternating relation, one from the other, on the respective ones of the first and second surfaces 14 and 16 by considering their relative positions as perhaps best shown in FIG. 1. As will now be clear from the illustrations and description, the first and second retention means 18 and 20 each comprise a pair of circumferentially spaced retaining segments 24 and 26 on the respective ones of the first and second surfaces 14 and 16.
Still referring to FIG. 1, the retaining segments 24 and 26 on the respective ones of the first and second surfaces 14 and 16 together comprise alternating positive projections and negative recesses defining superposed circular disc retention areas 28 and 30 on each of the first and second surfaces 14 and 16. In other words, the retaining segments 24 on the first surface 14 comprise positive projections relative to that surface and negative recesses relative to the second surface 16 whereas the retaining segments 26 on the second surface 16 comprise positive projections relative to that surface and negative recesses relative to the first surface 14. Moreover, as will be appreciated from FIG. 1, the retaining segments 24 and 26 on the respective ones of the first and second surfaces 14 and 16 are diametrically opposed with each of the retaining segments 24 and 26 extending about the corresponding one of the circular disc retention areas 28 and 30 by approximately 90°.
As best shown in FIG. 4, the retaining segments such as 26 on the respective ones of the first and second surfaces 14 and 16 each include a disc retaining lip such as 32 which is spaced from but ramped downwardly and inwardly toward the corresponding one of the first and second surfaces such as 16. The disc retaining lips such as 32 on the respective ones of the retaining segments 24 and 26 are diametrically opposed with each of the disc retaining lips such as 32 extending circumferentially about the corresponding one of the retaining segments such as 26 by an amount less than 90° (see, also, FIG. 3). By reason of the ramped surfaces such as 32a which extend downwardly and inwardly toward the corresponding surface such as 16, the diametrically opposed nature of the disc retaining lips such as 32 facilitate the insertion and removal of compact discs from the compact disc holder 10.
In this connection, and as previously mentioned, the single thickness panel 12 is preferably formed of a material such as thermoformed plastic so as to be flexible while at the same time self-supporting. This makes it possible for the compact disc to cause a slight separation as it is pressed inwardly toward the circular disc retention areas such as 30 by reason of the engagement of the peripheral edge of the compact disc with the corresponding ramped surfaces such as 32a. By reason of the flexible but self-supporting nature of the panel 12, the disc retaining lips such as 32 separate diametrically to permit passage of the compact disc to a position below the disc retaining lips such as 32.
As best shown in FIGS. 3 and 4, the compact disc holder 10 preferably includes a peripheral disc supporting segment such as 34 on the first and second surfaces 14 and 16 radially adjacent each of the retaining segments 24 and 26 which also together comprise alternating positive projections and negative recesses thereby further defining the superposed circular disc retention areas 28 and 30. The supporting segments such as 34 on the respective ones of the first and second surfaces 14 and 16 are diametrically opposed, one from the other, with each of the supporting segments such as 34 extending about the corresponding one of the retaining segments 24 and 26 through an arc of approximately 90°. Still referring to FIGS. 3 and 4, the compact disc holder 10 also includes a segmented disc hub support such as 36 radially inwardly of each of the retaining segments 24 and 26 on each of the first and second surfaces 14 and 16 which also together comprise alternating positive projections and negative recesses centrally disposed in each of the circular disc retention areas 28 and 30. The disc hub supports such as 36 on the respective ones of the first and second surfaces 14 and 16 are diametrically opposed one from the other with each of the disc hub supports such as 36 extending about the corresponding one of the circular disc retention areas 28 and 30 by approximately 90°.
As will be appreciated by referring to FIGS. 1 and 2, the first and second disc-supporting surfaces 14 and 16 are such as to define respective first and second generally parallel surface planes which necessarily cause the compact discs (see, also, FIG. 4) to be retained in respective first and second generally parallel disc planes. These planes are, of course, closely adjacent and parallel to the corresponding ones of the closely adjacent first and second generally parallel surface planes. As previously described, the positively-projecting retention means 24 and 26 of the first and second disc-supporting surfaces 14 and 16 are offset one from the other and, in particular, are circumferentially offset in alternating relation to grip compact discs so as to maintain them in generally parallel disc planes.
While not limited to any particular application, the compact disc holder 10 is well suited for use with a binder in which case the panel 12 may advantageously be formed as a thermoformed leaf. The thermoformed leaf 12 will be seen to have a marginal edge generally designated 37 for cooperation with a binder (not shown) and, for this purpose, the compact disc holder 10 may also include a hinging rib such as 38 on at least one of the first and second surfaces 14 and 16 generally adjacent the marginal edge 37. In addition, and as clearly shown in FIG. 1, the compact disc holder 10 may also include a plurality of holes such as 40 in the marginal edge 37 of the thermoformed leaf 12 for cooperation with a binder.
In the preferred embodiment, the first and second disc-supporting surfaces 14 and 16 each have positively-projecting retention means 24 and 26 for releasably retaining at least a pair of compact discs such that each of the pair of compact discs supported on the first surface 14 is in generally superposed relation with one of the pair of discs supported on the second surface 16. It will, thus, be appreciated that the compact disc holder 10 is well suited for supporting a total of four compact discs in such manner that each of the surfaces 14 and 16 is adapted to support two such discs. As will also be appreciated from FIGS. 1, 3 and 4, the retaining segments such as 24 and 26 each have an outermost surface such as 42 and 44 with a slot such as 46 and 48 extending generally tangential to the corresponding one of the circular disc retention areas such as 28 and 30 so that the slots 46 and 48 in the respective pairs of retaining segments 24 and 26 are diametrically opposed to releasably receive diagonally opposite corners of a booklet (see, especially, FIG. 3).
From the foregoing description, it will now be appreciated that the present invention makes it possible to utilize a single thickness of thermoformed plastic to provide functional storage for compact discs on both sides of a panel or leaf. This is accomplished using alternating positive projections and negative recesses which are so arranged as to permit nesting for shipment by reason of aligning the positive projections on one surface of one panel with the negative recesses of the opposite surface of an adjacent panel. Moreover, since it can be formed of thermoformed plastic, the compact disc holder can be inexpensively manufactured of recycled polystyrene with the thickness of the panel or leaf being selected such that there is a degree of flexibility while also providing self-supporting characteristics.
While not previously mentioned, the positive projections can have relatively large area flat surfaces to protect adjacent discs from one another. It is also contemplated that the thermoformed panel or leaf can have other embossments or ribs to provide additional rigidity if desired. Still further, booklets can be attached to the positive projections by a release adhesive rather than utilizing the tangential slots as an alternative.
With regard to the disc retaining lip and segmented disc hub support, they are provided to support the optical surface in slightly spaced relation to the remainder of the circular disc retention areas. They, too, comprise alternating positive projections and negative recesses as previously described. As a result of these features of construction, the disc retaining lips and segmented disc hub supports only contact the peripheral edge and central hub of the compact disc and not the optical surface.
As will finally be appreciated, the compact disc holder of the present invention is well suited for use with a binder wherein four compact discs can easily be supported on each thin panel or leaf in physically isolated relation to those on adjacent thin panels or leaves thereby maximizing storage capacity in a safe and highly economical manner.
While in the foregoing there has been set forth a preferred embodiment of the invention, it will be appreciated that the details herein given may be varied by those skilled in the art without departing from the true spirit and scope of the appended claims. | In order to releasably retain compact discs in an orderly fashion, a compact disc holder includes a single thickness panel having a first surface and a second surface opposite the first surface. The first surface has a first retention assembly for releasably retaining a compact disc and the second surface has a second retention assembly for releasably retaining a compact disc. With this arrangement, the retention assemblies are disposed on the respective surfaces of the single thickness panel to support compact discs in generally superposed relation. | 6 |
FIELD
[0001] The instant invention is in the field of wall construction. More specifically, the instant invention relates to modular panels for wall construction such as leave-in-place forms for poured concrete walls and more specifically to panels used to form wall corners.
BACKGROUND OF THE INVENTION
[0002] Forms for poured concrete walls comprising interlocking hollow blocks are known, see, for example, U.S. Pat. Nos. 4,703,602; 5,086,600; 5,855,102; 5,992,102 and 6,536,172. Forms for poured concrete walls comprising modular panels are known, see, for example, U.S. Pat. Nos. 4,884,382; 5,570,552; 5,983,585; 6,405,505 and especially 7,320,201. However, none of the prior art technology optimizes injection molding technology for wall corner applications.
SUMMARY OF THE INVENTION
[0003] An important benefit of the instant invention is that it allows a single user to incorporate several phases of construction into a single phase, thereby creating a finished wall having a corner. The instant invention is a kit for forming a hollow block assembly to be used to construct a wall having a corner, the kit comprising: at least two face panels, at least one inner left corner panel, at least one inner right corner panel, at least one outer left corner panel, at least one outer right corner panel and a plurality of fasteners, each panel comprising a plurality of spaced apart flanges extending from and attached to each panel so that a hollow block structure is assembled when the flanges of the panels are connected together, directly or indirectly, by the fasteners, wherein the panels are molded of a resin selected from the group consisting of a thermoplastic resin and a thermoset resin, wherein the flanges of the panels are integrally molded with the panels, wherein each flange of the panels is perforated therethrough with a plurality of apertures and wherein each fastener is a snap-lock strap molded of a resin selected from the group consisting of a thermoplastic resin and a thermoset resin and comprising projections therefrom molded integrally therewith, the projections dimensioned to be an interference fit when pressed through an aperture of a flange so that a hollow block structure is assembled when the projections of the straps are pressed through the apertures of the flanges of the panels, each left corner panel having a left corner edge, each right corner panel having a right corner edge, the left and right corner edges dimensioned to interconnect so that a hollow block structure having a corner is assembled when the projections of the straps are pressed through the apertures of the flanges of the face and corner panels.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a perspective rear view of a face panel of the prior art showing four flanges extending therefrom;
[0005] FIG. 2 is a perspective front view of a face panel of the prior art;
[0006] FIG. 3 is a perspective view of a snap-strap of the prior art;
[0007] FIG. 4 is a top view of the snap-strap of FIG. 3 ;
[0008] FIG. 5 is a side view of the snap-strap of FIG. 3 ;
[0009] FIG. 6 is a an end view of a pair of face panels of FIG. 1 attached to each other using snap-straps as shown in FIG. 3 ;
[0010] FIG. 7 is an end view from the other end of the assembly shown in FIG. 6 ;
[0011] FIG. 8 is a top view of two of the assemblies of FIGS. 6 and 7 engaged end to end and also showing a number of insulation panels;
[0012] FIG. 9 is a perspective view of a prior art base-plate system for use with the block assembly of the prior art;
[0013] FIG. 10 is a perspective view of a prior art half block outer corner for use with the block assembly of the prior art;
[0014] FIG. 11 is a perspective view of a prior art full block outer corner for use with the block assembly of the prior art; X
[0015] FIG. 12 is a perspective view of a prior art inner corner for use with the block assembly of the prior art;
[0016] FIG. 13 is a perspective view of a prior art end cap for use with the block assembly of the prior art;
[0017] FIG. 14 is a perspective view of a prior art top cap for use with the block assembly of the prior art;
[0018] FIG. 15 is a perspective view of a prior art perforated strap for use in the prior art;
[0019] FIG. 16 is a perspective view of a press-fit fastener for use in the prior art;
[0020] FIG. 17 is a perspective rear view of another prior art face panel of the prior art showing four flanges extending therefrom;
[0021] FIG. 18 is an end view of a pair of the face panels of FIG. 17 attached to each other using steel concrete reinforcing rods;
[0022] FIG. 19 is a perspective view of a preferred inner right corner panel of the instant invention;
[0023] FIG. 20 is a perspective view of a preferred inner left corner panel of the instant invention;
[0024] FIG. 21 is a perspective view of the panels of FIGS. 19 and 20 connected together to form a preferred inner corner of the instant invention;
[0025] FIG. 22 is a perspective view of a preferred outer left corner panel of the instant invention;
[0026] FIG. 23 is a perspective view of a preferred outer right corner panel of the instant invention;
[0027] FIG. 24 is a perspective view of the panels of FIGS. 22 and 23 connected together to form a preferred outer corner of the instant invention;
[0028] FIG. 25 is a perspective view of a face panel of the instant invention having aligning tabs on each side thereof;
[0029] FIG. 26 is a perspective view of a preferred snap-strap of the instant invention; and
[0030] FIG. 27 is a side view of the snap-strap of FIG. 26 .
DETAILED DESCRIPTION
[0031] Referring now to FIG. 1 , therein is shown a perspective rear view of a preferred face panel 10 of the prior art molded of a thermoplastic polymer or resin such as, without limitation thereto, impact modified polystyrene, polyethylene, PVC, PVC structural foam or a thermoset resin such as, without limitation thereto, a phenol-formaldehyde resin. The face panel 10 has four flanges 11 extending perpendicularly therefrom and integrally molded therewith. Each flange 11 is perforated therethrough with a plurality of apertures 12 . One side of the panel 10 has an alignment tab 13 . Referring now to FIG. 2 , therein is shown a perspective front view of the face panel of 10 of FIG. 1 . It should be understood that the face panels of the prior art can be made of any suitable material such as, without limitation thereto, galvanized sheet steel, sheet aluminum and wood or wood compositions such as chip board. Preferably, the face panels of the prior art are made of thermoplastic or thermoset resins. It should be understood that when the panels and/or fasteners of the prior art are made of molded thermoplastic, then recycled thermoplastic can be used to help advance the quality of the environment.
[0032] Referring now to FIG. 3 , therein is shown a perspective view of a preferred “snap-strap” 17 of the prior art molded of a thermoplastic polymer or resin such as, without limitation thereto, a plasticized polyvinyl chloride material or a thermoset resin such as, without limitation thereto, a polyurethane resin. The strap 17 comprises projections 18 therefrom molded integrally therewith. The projections 18 are dimensioned to be an interference fit when pressed through an aperture 12 of a flange 11 of the face panel 10 shown in FIG. 1 . FIG. 4 shows a top view of the snap-strap 17 of FIG. 3 . FIG. 5 shows a side view of the snap-strap 17 of FIG. 3 .
[0033] Referring now to FIG. 6 , therein is shown an end view of a hollow block structure 19 assembled when the projections 18 of the snap-straps 17 are pressed through the apertures of the flanges 11 of the face panels 10 . Referring now to FIG. 7 , therein is shown an end view of the hollow block structure 19 of FIG. 6 from the other end. In use, a number of block structures 19 are arrayed in a horizontal course with the side aligning tabs 13 fitted under the adjoining face panel. Then another horizontal course of block structures 19 is pressed in staggered fashion above the first course so that locking tabs 15 (also called snap buttons herein) of the face panels 10 engage with the holes or openings 16 in the upper aligning tabs 14 . Then, if desired, additional horizontal courses of block structures 19 are laid until the wall or footing form is as high as desired. Reinforcing steel rods can, of course, be inserted as desired as the courses are laid. If larger panels are used, then a wall can be formed from one course of the block structures of the prior art.
[0034] Referring again to FIG. 5 , it will be noted that the preferred shape of the projections 18 is in the form of a chevron in cross-section. However, it should be understood that other shapes (such as a spheroid) can be used if desired. The outside diameter of the projections 18 is somewhat larger than inside diameter of the apertures 12 so that the projections 18 are an interference fit when the projections 18 are pressed through the apertures 12 to assemble the block structure 19 of FIG. 6 .
[0035] Referring again to FIG. 1 , it is preferable to mold four flanges 11 from the face plate 10 as shown so that half or even quarter blocks can be assembled by sawing the face plate 10 in half or in quarters. Although the block assembly 19 of FIGS. 6 and 7 is assembled from identical face plates 10 , it should be understood that a face plate which is a mirror image of the face plate 10 is preferred so that the side aligning tabs of a block assembly face the same direction.
[0036] Referring now to FIG. 8 , therein is shown a top view of two of the assemblies 19 of FIGS. 6 and 7 engaged end to end. Closed cell polystyrene foam thermal-insulation panels 20 are then inserted as shown and are highly preferred as providing not only thermal insulation but added strength to the form to withstand the hydraulic pressure of the fluid concrete poured into the form before the fluid concrete cures. And, if larger panels are used, then an insulated wall, insulated with, for example and without limitation thereto, fiberglass or blown-in cellulose insulation, can be formed from one course of the block structures of the prior art even if the wall is not filled with concrete.
[0037] The exterior and/or interior of the face panels of the prior art are preferably “finish-faced”. The term “finish-faced” means an external surface not requiring further finishing. Such an external surface could be, for example and without limitation thereto, a stucco type of surface or vertical lines that could-disguise, if desired, the vertical joints of the wall. The face panels can, of course, be molded of a colored thermoplastic or thermoset polymer or resin so that the finished wall does not require painting. The prior art can be used, of course, to make footings, foundation walls and walls above grade.
[0038] An important benefit of the prior art is that by the use of snap-straps of different lengths, walls and the like can be constructed of different thicknesses. The use of relatively long face panels of appropriate design permits the ready adaptation of the prior art to the construction of curved walls.
[0039] Referring now to FIG. 9 , therein is shown a base-plate system 21 for use with the hollow blocks of the prior art. The base-plate system 21 consists of a front face 22 and a rear face 23 connected by snap straps 24 (all of which are preferably injection molded of a thermoplastic or thermoset resin). In use, the base plate system 21 can be, for example, grouted to a footing. The locking tabs ( 15 of FIG. 6 ) of the first course of hollow blocks of the prior art are then located over and pressed into the holes 25 in the front and rear faces 22 and 23 . Alternatively, the first course of hollow blocks of the prior art can simply be grouted to the footing.
[0040] Referring now to FIG. 10 , therein is shown a perspective view of a preferred half block outer corner 26 for use with the hollow blocks of the prior art which is preferably also molded of a thermoplastic or thermoset resin. Referring now to FIG. 11 , therein is shown a perspective view of a preferred full block outer corner 27 for use with the hollow blocks of the prior art which is preferably also molded of a thermoplastic or thermoset resin. Referring now to FIG. 12 , therein is shown a perspective view of a preferred full inner corner 28 for use with the hollow blocks of the prior art which is preferably also molded of a thermoplastic or thermoset resin. Referring now to FIG. 13 , therein is shown a perspective view of a preferred end cap 29 for use with the hollow blocks of the prior art (which is preferably also molded of a thermoplastic or thermoset resin) if it is desired to end a wall or footing. The end cap 29 can be held in place by screws, not shown, driven through the end of a hollow block to engage the tabs 29 a of the end cap 29 . Referring now to FIG. 14 , therein is shown a perspective view of a preferred top cap 29 for use with the hollow blocks of the prior art (which is preferably also molded of a thermoplastic or thermoset resin) if it is desired to finish the top of a wall or footing. The top cap 29 preferably has locking tabs (like the locking tabs 15 of FIG. 1 ) molded with the skirt 30 a of the top cap 29 to engage with the holes in the aligning tabs of the hollow block of the prior art.
[0041] The snap strap 17 of FIG. 3 is an example of a fastener for the indirect connection of a flange of one face panel to a flange of another face panel. Referring now to FIG. 15 , therein is shown a strap 31 perforated therethrough with apertures 32 . Of course, the flanges of the face plates discussed above can be molded or otherwise formed to have projections which are dimensioned to be an interference fit when pressed through the apertures 32 of the strap 31 . And, of course, the flanges of one panel can have apertures while the corresponding flanges of the other panel can be molded or otherwise formed to have projections which are dimensioned to be an interference fit when pressed through said apertures. However, referring now to FIG. 16 , therein is shown a “X-Mass Tree Clip” fastener” 33 available from K-International of Gurnee, Ill. Thirty two of such fasteners 33 can be used to attach one face plate 10 of FIG. 1 to another face plate 10 of FIG. 1 by pressing said fasteners through the apertures 32 of the strap 31 of FIG. 15 and the apertures 12 of the face plate 10 of FIG. 1 to produce a block assembly similar to the block assembly 19 of FIG. 6 . The outside diameter of the chevrons 34 of the fastener 33 are dimensioned to be an interference fit in the apertures 32 and 12 . A simple length of wire can be used as a fastener to attach one panel to another panel by passing the wire through the apertures of the flanges of the panels and bending the wire around the apertures. The fastener 33 is but one example of a whole family of press-fit fasteners which are commercially available. For example, and without limitation thereto, said K-International offers snap rivets, Viking clips, quick grip fasteners, dart clips, ratchet rivet fasteners and arrow clips. And, of course, conventional fasteners such as nuts and bolts can also be used.
[0042] Referring now to FIG. 17 , therein is shown a perspective rear view of a preferred face panel 35 of the prior art molded of a thermoplastic polymer or resin such as, without limitation thereto, impact modified polystyrene, polyethylene or a thermoset resin such as, without limitation thereto, a phenol-formaldehyde resin. The face panel 35 has four flanges 40 extending perpendicularly therefrom and integrally molded therewith. Each flange 40 is perforated therethrough with a plurality of apertures 41 . Each panel 35 has side aligning tabs 36 , upper aligning tabs 39 , holes 38 and locking tabs 37 . Two panels 35 can be joined together by pressing fasteners 33 of FIG. 16 through the apertures 41 of each face plate 35 . Alternatively, any desired fastener can be used for this purpose.
[0043] Referring now to FIG. 18 , when it is desired to produce a poured reinforced concrete wall, a preferred fastener for connecting the face panels together is a number of steel concrete reinforcing rods 42 positioned in the apertures 41 of the panels 35 of FIG. 17 . Preferably, the outside diameter of the rods 42 is smaller than the inside diameter of the apertures 41 .
[0044] Referring again to FIGS. 10-12 , the molds needed to mold such prior art corner panels have been found to be more complex than desired. Referring now to FIGS. 19-24 , therein is shown a preferred means of forming a wall having a corner according to the instant invention. The molds needed to mold the panels shown in FIGS. 19-24 are less complex than the molds needed to mold the panels shown in FIGS. 10-12 . Otherwise, the teachings above regarding the system shown in FIGS. 1-18 apply to the panels and straps of FIGS. 19-24 .
[0045] Referring now to FIG. 19 , therein is shown a perspective view of a preferred inner right corner panel 43 of the instant invention. In most respects the panel 43 is the similar to the panel 10 of FIG. 1 . However the panel 43 has perforated projections 44 attached to the panel 43 at the inside left edge thereof Referring now to FIG. 20 , therein is shown a perspective view of a preferred inner left corner panel 46 of the instant invention. In most respects the panel 46 is the similar to the panel 10 of FIG. 1 . However the panel 46 has snap-lock projections 47 attached to the panel 46 at the inside right edge thereof Referring now to FIG. 21 , therein is shown a perspective view of the panels of FIGS. 19 and 20 connected together to form a preferred inner corner of the instant invention. The perforated projections 44 and snap-lock projections 47 of FIGS. 19 and 20 are not critical in the instant invention and any suitable substitute joining system can be used (such a single hinge pin or a dovetail joint) as long as the panels 43 and 46 interconnect at the appropriate edges thereof.
[0046] Referring now to FIG. 22 , therein is shown a perspective view of a preferred outer left corner panel 49 of the instant invention. In most respects the panel 49 is the similar to the panel 10 of FIG. 1 . However the panel 49 has perforated projections 50 attached to the panel 49 at the inside right edge thereof. Referring now to FIG. 23 , therein is shown a perspective view of a preferred outer right corner panel 51 of the instant invention. In most respects the panel 51 is the similar to the panel 10 of FIG. 1 . However the panel 51 has snap-lock projections 52 attached to the panel 51 at the inside left edge thereof. Referring now to FIG. 24 , therein is shown a perspective view of the panels of FIGS. 22 and 23 connected together to form a preferred outer corner of the instant invention. The perforated projections 50 and snap-lock projections 52 of FIGS. 22 and 23 are not critical in the instant invention and any suitable substitute joining system can be used (such a single hinge pin or a dovetail joint) as long as the panels 43 and 46 interconnect at the appropriate edges thereof.
[0047] Referring now to FIG. 25 , therein is shown a perspective view of a face panel 54 of the instant invention. The face panel 54 is similar in most respects to the face panel 10 of FIG. 1 but the face panel 54 has aligning tabs 55 and 56 on each side thereof The face panel 54 has utility when used with the assemblies shown in FIGS. 21 and 24 to form a wall having a corner.
[0048] Referring now to FIG. 26 , therein is shown a perspective view of a preferred snap-strap 57 of the instant invention having molded in place flexible projections 58 and a molded reinforcement section 59 . Referring now to FIG. 27 , therein is shown a side view of the snap-strap of FIG. 26 .
CONCLUSION
[0049] While the instant invention has been described above according to its preferred embodiments, it can be modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the instant invention using the general principles disclosed herein. Further, the instant application is intended to cover such departures from the present disclosure as come within the known or customary practice in the art to which this invention pertains and which fall within the limits of the following claims. | A kit for forming a hollow block assembly to be used to construct a wall having a corner, the kit consisting of face panels, right and left corner panels and a plurality of fasteners, each panel comprising a plurality of spaced apart flanges extending perpendicularly from and attached to each panel so that a hollow block structure is assembled when the flanges of the panels are connected together, directly or indirectly, by the fasteners, the right and left corner panels being dimensioned to interconnect at the edges thereof to form a corner section of a wall. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to insulated glass and more particularly to spacers and muntins used within insulated glass.
Insulated glass is well known and widely used in a variety of applications such as doorlights. Insulated glass includes a pair of panes or panels of glass separated by a spacer. Typically, the spacer is aluminum and extends around the perimeter of the assembly, defining a space between the glass panes. The panels are adhered and sealed to the spacer to secure the assembly together. A desiccant is included within the spacer to absorb moisture within the insulated glass space. The space may be filled with an inert gas to enhance the insulation effect.
Often a muntin or grille also is included within the insulated glass. Typically, such an “internal” muntin is aluminum and is positioned between the panes within the confines of the spacer to provide an aesthetically pleasing appearance to the window. Such a construction is illustrated, for example, in U.S. Pat. No. 3,308,593, issued Mar. 14, 1967 to Smith and entitled “Panel For Inclusion In A Unit To Be Installed In A Building Opening.” Unfortunately, the inclusion of the muntin is relatively expensive and labor intensive. Care must be taken during the manufacture of the muntin and the assembly of the insulated glass to ensure that the muntin is properly fabricated and positioned within the assembly. Aesthetics are important to the commercial success of the insulated glass.
SUMMARY OF THE INVENTION
The aforementioned problems are overcome in the present invention wherein a spacer unit is provided that is a one-piece, integral unit including both a spacer portion and a muntin portion. The spacer unit may be fabricated, for example, of injection-molded plastic. The spacer portion is continuous and extends around the entire perimeter of the insulated glass. The muntin portion is integral with the spacer. The glass panels are adhered to the spacer portion. The muntin portion is suspended within the space between the glass panels, and the muntin portion is spaced from the glass panels.
The present invention produces an insulated glass with an internal muntin that is simpler and less expensive than prior art insulated glass. It also provides improved aesthetic and functional benefits. The seal of the glass panels to the spacer is enhanced at the corner because the spacer portion is continuous at the corners. The spacing of the muntin portion from the glass panels reduces “rattling.” Molding the spacer and muntin of plastic and spacing the muntins from the glass reduces thermal transmission through the insulated glass. Because the product includes a plastic spacer, it is less likely to generate condensation than prior art assemblies using aluminum spacers. Further, because the muntin is integral with the spacer, assembly joints are eliminated to enhance aesthetics.
These and other objects, advantages, and features of the invention will be more fully understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective exploded view of the insulated glass of the present invention shown in conjunction with a doorlight frame;
FIG. 2 is a perspective view of the insulated glass of the present invention;
FIG. 3 is a sectional view taken along line III—III in FIG. 2;
FIG. 4 is a sectional view similar to FIG. 3 showing an alternative embodiment of the muntin cross-section; and
FIG. 5 is a sectional view taken along line V—V in FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An insulated glass (also referred to as IG) constructed in accordance with a preferred embodiment of the invention is illustrated in the drawings and generally designated 10 . The insulated glass 10 includes a spacer unit 12 and a pair of glass panes or panels 14 and 16 adhered to opposite sides thereof. The spacer unit 12 includes a peripheral spacer portion 20 and an internal muntin portion 30 . The panels 14 and 16 are adhered to the spacer portion 20 and are spaced from the muntin portion 30 .
FIG. 1 illustrates the insulated glass 10 in conjunction with a pair of doorlight frame halves 17 and 18 . The frame halves 17 and 18 are generally well known to those skilled in the art and therefore will not be described in detail. For example, the frame halves can be constructed in accordance with U.S. Pat. No. 5,644,881 issued Jul. 8, 1997 to Albert J. Neilly and entitled “Window Frame with Integral Connectors,” the disclosure of which is incorporated by reference.
The glass panes or panels 14 and 16 also are generally well known to those skilled in the art and can be any known glazing panel. For example, the glass used in the described embodiment of the invention is a fully tempered glass that is ⅛ inch thick, such as that sold by AFG of Kingsport, Tenn. Other materials can and are substituted for the glass panels. Other suitable materials include polycarbonates, acrylics, plastics, and virtually any other translucent or transparent material.
The spacer unit 12 is new to the present invention and includes a spacer portion 20 and a muntin portion 30 . The spacer portion 20 includes a body 21 having a pair of opposite channels 22 and 23 to which the panels 14 and 16 are adhered. The cross section of the spacer portion 20 is uniform throughout the entire perimeter of the spacer unit 12 . The channels 22 and 23 are slightly concave to receive sealant between the spacer portion 20 and the panels 14 and 16 . In the preferred embodiment, the body portion 21 maintains the panels 14 and 16 a fixed distance apart of approximately ¾ inch. The spacing may vary depending on the particular application. The spacer portion 20 includes an interior face 25 and an exterior face 24 . The interior face 25 defines a pair of grooves 26 and 27 , which extend the full perimeter of the spacer portion 20 to receive a desiccant or desiccant matrix 40 .
The muntin or grille portion 30 includes one or more horizontal muntins 31 and/or one or more vertical muntins 32 . The muntins 31 and 32 visually divide the insulated glass 10 into evenly sized smaller panes. However, the muntin could be constructed to visually divide the area into any desired pattern. As illustrated in FIG. 3, all of the muntins 31 and 32 are generally rectangular in cross section and are spaced from the glass panels 14 and 16 so that the panels do not and cannot engage the muntins. This construction prevents the muntins from rattling against the glass when the assembly is subjected to lateral forces, such as when a door opens or shuts. As disclosed, the depth D of the muntins is ⅜ inch.
The cross section of the muntins can be varied as desired, for example, for strength and aesthetics. FIG. 4 illustrates an alternative cross section for the muntins 32 ′. This cross section is useful when the muntins are intended to simulate the appearance of wood moldings. The alternative muntin 32 ′ also is spaced from both of the glass panels 14 and 16 and as a depth generally the same as that of muntin 32 .
Assembly and Operation
The assembly of the insulated glass 10 is perhaps best illustrated in FIG. 5 . As a preliminary step, a caulk-type desiccant matrix 40 is applied to the spacer unit 12 in either or both of the grooves 26 and 27 . The currently preferred desiccant is that sold under the designation Adco Therm Desiccant Matrix by Adco of Michigan Center, Mich. Other appropriate desiccants and desiccant matrices will be known to those skilled in the art. The desiccant matrix 40 may be applied in either, both, or neither of the grooves 26 and 27 ; and the desiccant may extend for all or any portion of the perimeter of the spacer portion 20 . It also is foreseen that the desiccant could be molded into the plastic of which the spacer 12 is fabricated.
Butyl adhesive or sealant 50 is applied to the faces 22 and 23 of the spacer portion 20 . The butyl 50 extends around the entire perimeter of the spacer portion 20 . The adhesive in the preferred embodiment is that sold under the designation 2000HS by Adco of Michigan Center, Mich. Other appropriate sealants are and will be known to those skilled in the art.
The panels 14 and 16 with the spacer unit 12 are laid up as a sandwich. Optionally, an edge sealant (not shown) such as polysulfide can be applied to the edge of the insulated glass 10 . The entire assembly is run through pinch rollers or other appropriate equipment to improve proper adhesion of the components and to ensure consistent thickness of the glass assemblies.
Because the spacer unit 12 is fabricated of an integral, one-piece construction, the assembly has several advantages. First, the spacer portion 20 is continuous around the entire perimeter of the insulated glass 10 , including in the corners. This eliminates the requirement of corner keys between individual spacer elements as are conventional in the art. Second, the muntin portion 30 is integrally and automatically provided within the insulated glass 10 as the spacer unit 12 is put into position. The positions of all muntins 31 and 32 are properly provided, and the muntins are not fragile as in prior constructions. Accordingly, the possibility of misaligning or damaging the muntin during assembly is virtually eliminated. Also, the absence of fabrication joints between crossing muntins 31 and 32 and between the muntin portion 30 and the spacer portion 20 enhances the aesthetics. Third, the spacing of the muntin portion 30 from the panels 14 and 16 ensures that the muntins do not rattle against the panes if the insulated glass is subjected to a lateral force, for example, as might occur when a window or door is slammed open or shut. Fourth, because the spacer unit 12 is plastic, thermal transmission is reduced. In summary, the insulated glass 10 with the spacer unit 12 is easier to assemble, has fewer components, is less subject to damage or failure, is more aesthetically pleasing, and provides improved thermal transmission properties than previously known insulated glass with aluminum spacers and internal muntins.
The above description is that of a preferred embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law, including the doctrine of equivalents. | An improved insulated glass including a spacer unit and a pair of glazing panels bonded to opposite sides thereof. The spacer unit includes a peripheral spacer portion and a muntin portion within the spacer portion. The spacer unit is a one-piece, injection-molded unit, and consequently the spacer portion and the muntin portion form an inseparable integrated whole. | 4 |
This is a division of co-pending application Ser. No. 075,401 filed on July 20, 1987, now U.S. Pat. No. 4,814,213.
BACKGROUND OF THE INVENTION
Decorative glass assemblies are utilized in many situations including as door lights and as door side glass units. Leaded glass assemblies using multiple pieces of bevelled glass have been used in the past and are very beautiful but very expensive. Many prior art alternative assemblies use a flat glass sheet with bevelled glass bonded to it or wood or wood-like grilles, which are normally positioned on the surface of the glass sheet and secured to the perimeter. These grlles damage easily, are difficult to clean and lack appeal.
SUMMARY OF THE INVENTION
The present invention is directed to a bevelled glass assembly which is tempered. It provides a lightweight and attractive alternative to both leaded glass and prior art grille assemblies.
The bevelled glass assembly, according to the present invention, includes a sheet of annealed glass which has at least one first longitudinally extending groove ground into one surface. The groove comprises an array of paralled surface striations which enhance optical reflections. At least one longitudinally extending second groove intersects the first groove. The second intersecting groove also includes an array of parallel surface striations. The sheet of annealed glass containing the ground grooves is tempered.
In making the bevelled glass assembly, a sheet of flat glass is annealed and the intersecting grooves are ground within one surface of the glass sheet, the grooves including the arrays of parallel surface striations. The glass is then polished. The tempering is performed after the grinding of the intersecting grooves and the polishing of the glass sheet.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a bevelled glass assembly, according to the present invention;
FIG. 2 is a fragmentary cross-sectional view, shown on an enlarged scale taken along the line 2--2 of FIG. 1;
FIG. 3 is a fragmentary perspective view taken roughly along the line 3--3 of FIG. 1, shown on an enlarged scale;
FIG. 4 is a fragmentary view of another embodiment of a bevelled glass assembly, according to the present invention, with a portion of the peripheral frame removed;
FIG. 5 is a fragmentary perspective view, similar to FIG. 3, and showing a bevel groove having a generally trapezoidal cross section; and
FIG. 6 is a fragmentary cross-sectional view of another embodiment of the present invention showing a double pane insulated bevelled glass assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A bevelled glass assembly, according to the present invention, is generally indicated in FIG. 1 by the reference number 10. The bevelled glass assembly 10 comprises a sheet of annealed glass 11. Preferably the glass sheet 11 is flat plate glass manufactured by a float glass process. The glass sheet 11 preferably has a relatively low lead content of less than 15% lead, by weight. After its initial manufacture, the flat plate glass is annealed. It is found that a glass thickness of between 0.125 inch and 0.250 inch is preferable for the bevelled glass assemblies 10, when they are utilized in connection with residential or commercial door or window applications.
A first set of longitudinally extending grooves 12 are ground into a surface 13. Referring to FIG. 3, the grooves 12 comprise an array of parallel surface striations 14. The parallel surface striations 14 enhance optical reflections giving pleasing aesthetics to the assembly 10.
In the FIG. 1 embodiment, the grooves 12 are ground to a depth of 0.062 inch on a glass sheet having a thickness of 0.188 inch. The width of the groove 12 is 0.375 inch. The grooves can be V-shaped, curved, trapezoidal or some other cross-sectional shape. Referring to FIG. 5, a groove 15 has a trapezoid cross section.
Referring to FIG. 1, at least one second longitudinal groove 16 intersects the first set of grooves 12. In the FIG. 1 embodiment, the grooves 12 and 16 are perpendicular, however, intersections forming nonperpendicular relationships or diamond shape relationships are also within the scope of the present invention.
The second intersecting longitudinally extending groove 16 also is comprised of an array of parallel surface stiations and has a depth and width complementary with the depth and width of the grooves 12, recited above.
After the longitudinally extending grooves 12 and 16 are ground, the glass sheet 11 is polished and tempered.
Referring to FIG. 1, the glass sheet 11 has a peripheral edge 18. The edge corners may be radiused or ground to aid the tempering process. Ends 19 of the grooves 12 and 16 are spaced from the peripheral edge 18. In the FIG. 1 embodiment, the ends 19 are 0.50 inch from the peripheral edge 18.
A second embodiment of a bevelled glass assembly, according to the present invention, is indicated in FIG. 4 by the reference number 30. The bevelled glass assembly 30 includes a sheet of annealed glass 31 having a surface 32. A first set of longitudinally extending grooves 33 are ground in the surface 32 of the sheet of annealed glass 31. Each of the longitudinally extending grooves 33 comprises an array of parallel surface striations. An intersecting second set of grooves 35 are ground in the surface 32 in a perpendicular relationship to the first set of grooves 33. The grooves 33 and 35 include ends 36 which are located adjacent a peripheral edge 37 of the glass sheet 31.
In the embodiment shown in FIG. 4, the bevelled glass assembly 30 includes a peripheral frame 39 which surrounds the peripheral edge 37 of the glass sheet 31. Perferably, the peripheral frame 39 extends inwardly past the ends 36 of the grooves 33 and 35. The frame 39 may be constructed of several materials, including woods, plastic resins having a wood-like appearance and metals.
After the grooves 33 and 35 are ground into the surface 32 of the glass sheet 31, the sheet 31 is polished and the glass tempered prior to installation of the peripheral frame 39.
Another embodiment of the invention is shown in FIG. 6. A bevelled glass sheet 46, similar to the bevelled glass sheet 11, shown in FIG. 1, is spaced from an unbevelled sheet of flat glass 47 forming an air space 48. The sheets 46 and 47 are held apart by a spacer 50. Sealing material 51 is placed between the sheets 46 and 47, adjacent the spacer 50. The sheets 46 and 47 are received by a peripheral frame 52 to form an insulated glass assembly 53.
It has been found that an observer looking through the bevel on a first surface 55 of the assembly 53 perceived an unexpected enhanced image through the second surface 56 onto the third surface 57. Therefore, the assembly 53 has excellent optical appeal. The placement of the bevel grooves on the inside or second surface 56 of the sheet 47 does not substantially change the visual effect. However, it has been found that the feel of the groove when touched enhances the appeal of the assembly 53.
It has been found that the bevelled glass assemblies 10, 30 and 53 constructed according to the present invention, provide a lightweight and lower cost alternative to, for example, prior art leaded glass assemblies. | A bevelled glass assembly and method of making is disclosed. A sheet of annealed glass has at least one groove ground on one surface. At least one other groove intersects the first groove. Both grooves define an array of parallel striations. The sheet of glass is then tempered. The sheet of glass is normally surrounded by a frame. | 1 |
BACKGROUND AND SUMMARY
U.S. Pat. No. 4,086,829 discloses a ratchet wrench having a handle which may be turned about its own axis to rotate the transversely-directed head of the wrench, as long as the resistance to head rotation is below a preselected torque load level, to tighten or loosen a nut or other workpiece. The wrench thus has two operating modes: a first mode in which rotation is imparted to the head by turning the handle about its longitudinal axis, and a second mode in which rotation is imparted to the head by oscillating the handle back and forth in a conventional ratchet wrenching operation. The two modes are non-interfering so that, for example, during the ratcheting operation there will be insufficient feedback to cause the handle to twist in the user's hand.
This invention is concerned with a wrench which has the dual operating modes of the wrench of U.S. Pat. No. 4,086,829 but which has important structural differences which yield improved clutch action, increased handle strength, reduced exposure to damage, increased protection against contact by fluids that might adversely affect wrench operation, and significantly lower manufacturing costs.
The improved wrench of this invention has a single-piece handle which is solid throughout substantially its entire length, thereby yielding greater strength and reduced manufacturing costs in comparison with a centrally-bored handle of machined, two-piece construction. The clutch mechanism is disposed within and protected by the head housing, along with other components of the wrench's operating mechanism. Since the handle is formed in one piece and requires no machining or drilling in production, it may be drop-forged for even greater strength and dependability.
In brief, the ratchet wrench includes an elongated handle with a head assembly at one end of that handle, the head assembly comprising a head housing rotatably receiving the end of the handle, a drive member carried by the housing for rotation about an axis transverse to the axis of the handle, and a ratchet-equipped coupling assembly operatively joining the drive member and housing for rotation of the drive member one way or the other about the transverse axis in response to oscillation of the handle. Within the head housing is a clutch assembly which couples the handle and the drive member for simultaneous rotation about their respective axes only below a preselected torque load level. Specifically, the clutch assembly includes a clutch sleeve and a clutch body interposed between and operatively connected to the handle and the drive member, respectively, the sleeve being slidable relative to the clutch body when the preselected torque load level is exceeded. In the disclosed embodiment, the sleeve is provided at opposite ends with a pair of inwardly tapering frusto-conical clutch surfaces and the clutch body takes the form of a clutch nut and a clutch gear having frusto-conical outer surface portions received in the ends of the sleeve and frictionally engaging the tapered surfaces of that sleeve. Adjustable connecting means extend through the sleeve to join the clutch nut and clutch gear for limited axial adjustment while at the same time securing such parts against independent relative rotation. The torque load level may therefore be varied by adjusting the connecting means and the force with which the conical surfaces of the clutch nut and clutch gear engage the sleeve. The sleeve is in turn formed of a tough, durable, but slightly deformable material, such as nylon or other polymeric material having similar characteristics, so that the outward forces exerted upon the sleeve by the clutch nut and clutch gear will cause the sleeve's outer surface to tightly engage the inner surface of the cavity of the handle in which the clutch assembly is located. The adjustable connecting means therefore performs the dual functions of setting the torque load limit of the clutch and locking the sleeve against rotation relative to the handle.
Other features, objects, and advantages will become apparent from the specification and drawings.
DRAWINGS
FIG. 1 is a fragmentary side elevational view, taken partly in section, showing the operating mechanism of a wrench embodying the invention.
FIG. 2 is a bottom elevational view of the wrench.
FIG. 3 is an exploded perspective view of the wrench.
FIG. 4 is an enlarged fragmentary longitudinal sectional view showing details of the clutch assembly.
DETAILED DESCRIPTION
Referring to the drawings, the numeral 10 generally designates a speed handle ratchet wrench having an elongated handle 11 and a head assembly 12 disposed at one end of the handle. The handle, shown most clearly in FIG. 3, takes the form of a solid and generally cylindrical bar which may have its outer surface knurled at one end 11a to provide a non-slipping surface for gripping the handle. The opposite end 11b is provided with a recess or cavity 13 and an annular groove 14. The entire end portion 11b is received within the housing 15 of the head assembly with retaining rings 16 and 17 being located in groove 14 to retain the end portion 11b of the handle within the head housing while at the same time permitting relative rotation of the parts. If desired, for purposes of balance and appearance, the shank portion 11c of the handle may be reduced in diameter as illustrated most clearly in FIG. 3. Since the handle is solid, and may be drop-forged for even greater strength, such a reduction in size and weight may be achieved without any objectable reduction in strength.
Head housing 15 defines a chamber 18 having a cylindrical portion 18a for rotatably receiving end portion 11b of the handle (FIG. 1). Cavity 18 also includes a second portion 18b disposed at right angles to portion 18a for rotatably receiving drive member 19. The drive member includes a square lug portion 20 at its exposed lower end, a bevel gear portion 21 at its opposite end, and an enlarged sprocket or toothed wheel portion 22 intermediate its ends. The sprocket is engagable with a pawl 23 which is adjustable into either of two positions by means of an external selector level 24. When the lever is in the position shown in solid lines in FIG. 2, the pawl locks the sprocketed drive member in one direction so that as the handle 11 is oscillated the drive member will be rotated in a clockwise direction (when viewed from above) to tighten nuts or other work objects, whereas if the lever 24 is shifted into the other position depicted by broken lines in FIG. 2, oscillation of the handle will cause the drive member 19 to be rotated in a reverse or counterclockwise direction (when viewed from above) to loosen such work objects. A spring loaded detent 25 holds the pawl in each of its selected positions of adjustment. Since the detent, pawl, and drive member are all quite conventional in structure and operation, and are typically found in any standard reversible ratchet wrench, discussion of such elements in greater detail is believed unnecessary herein.
A suitable cover 26 may be secured to the underside of the head housing 15 by means of screws 27 (FIG. 2) threaded into openings 28 of the housing, or by any other appropriate connecting means.
A clutch and power-transmitting assembly 30 is located within the chamber 18 of head housing 15. Referring to FIG. 1, it will be observed that the clutch assembly is in fact almost completely encased within recess 13 in end portion 11b of the handle which is in turn received within the chamber 18 of the head housing. Consequently, the load-limiting clutch assembly is fully protected by both the handle and the head housing.
The clutch assembly 30 consists essentially of a clutch sleeve 31 and a clutch body 32, the latter in turn being composed of a clutch gear 33, clutch nut 34, and connecting means 35. The clutch sleeve has a cylindrical outer surface 31a dimensioned to be received within cylindrical recess 13 of the handle, and has an axial bore defined by frusto-conical portions 31b tapering inwardly from opposite ends of the sleeve to join an intermediate central portion 31c (FIG. 4). Ideally, the sleeve is formed of a tough polymeric material such as nylon which is capable of limited expansion; however, other types of materials might conceivably be used.
Clutch nut 34 has a frusto-conical outer surface 34a which mates with one of the frusto-conical end surfaces of the sleeve. Similarly, clutch gear 33 has a frusto-conical outer surface 33a which mates with surface 31b at the opposite end of the sleeve. The clutch gear 33 and clutch nut 34 are maintained in coaxial relation with the sleeve 31 by means of connecting means 35, such connecting means also serving the additional purposes of locking the nut and gear against independent rotation while at the same time allowing limited axial adjustment of the spacing between such parts. Referring to FIGS. 3 and 4, it will be seen that the connecting means takes the form of a screw 36 and a tubular hub 37. The hub is secured to the clutch gear 33 by being test fitted therein; however, other means may be used to join the hub and gear together and, if desired, the two parts may even be formed integrally. In any event, the gear hub has a central bore 37a which rotatably receives the shank of screw 36. The end portion 37b of the hub projecting from the frusto-conical portion of the clutch gear 33 is non-circular (preferably square) in cross sectional outline and is slidably received within a square opening 34b extending inwardly from the reduced end of clutch nut 34. The nut is also provided with a threaded axial bore 34c for threadedly receiving the end of screw 36 (FIG. 4). Consequently, when the parts are assembled as shown, the tightening of screw 36 draws the coaxial clutch gear 33 and clutch nut 34 towards each other and into increasingly tight engagement with the frusto-conical inside surfaces of clutch sleeve 31. The outward force tends to cause radial expansion of the sleeve; however, such expansion is limited not only by the material from which the sleeve is formed but also by the close fit between the sleeve's outer surface and the cylindrical wall of recess 13. Consequently, tightening of screw 36 also has the effect of locking sleeve 31 in place within the recess 13 of handle 11.
It will be appreciated that relative rotation of the sleeve 31 and handle 11 may be insured against by forming one or both of the contacting surfaces so that rotational sliding movement is not possible even before tightening of screw 36. For example, surface 31a of the sleeve, as well as the opposing surface of the recess 13, might be splined, roughened, or formed in non-circular cross sectional configuration. As a practical matter, it has been found that if the handle is cast, and cavity 13 is not reamed or at least not polished, the surface of that cavity effectively prevents any relative rotation of sleeve 31 when screw 36 is tightened to cause limited expansion of that sleeve. Therefore, during operation of the wrench, the slipping action of the clutch will occur entirely between the frusto-conical surfaces of gear 33 and nut 34 and the mating frusto-conical surfaces of the clutch sleeve 31.
Should the cylindrical surface of handle recess 13 be polished, and especially if the frusto-conical surfaces of the sleeve 31, gear 33, and nut 34 are longitudinally grooved, roughened, or formed in non-circular cross sectional outline, the sleeve 31 may be assembled to rotate with the gear and nut, and the clutching/slipping action would then take place between the outer cylindrical surface 31a of the sleeve and the cylindrical surface of recess 13.
During fabrication of the wrench, screw 36 is tightened to achieve a preselected torque load limit. While adjustment of that limit by the user would not normally be anticipated, it is believed apparent that if retaining rings 16 and 17 are designed for ease of removability, or if some other means is selected for detachably securing the handle 11 and head housing 15 together, such adjustment may be readily effected. It will also be noted that even with the construction shown, a user may adjust the torque limit of the wrench by removing cover 26 and drive member 19 and then inserting a suitable right-angled screw driver into the cavity 18 of the head housing to loosen or tighten the adjustment screw.
The wrench is used in essentially the same manner as disclosed in my aforementioned U.S. Pat. No. 4,086,829. For example, if a nut is to be tightened by the wrench, the user first fits the nut upon the threaded end of the bolt, then engages the wrench with the nut in the usual manner, and then rotates handle 11 about its own longitudinal axis to cause limited tightening of the nut. As soon as the torque load limit is reached, further rotation of the handle will cause the clutch to slip, a fact which may be readily ascertained by tactile sensation through the handle. Final tightening of the nut is then accomplished by using the wrench in its conventional manner, oscillating the handle back and forth about the transverse axis (such axis being represented by line 39 in FIG. 3) of the wrench to rotate the drive member 19 and the nut to which it is coupled. As the handle swings in one direction to tighten the nut, the ratchet means secures the drive member against rotation with respect to the head assembly; as the handle swings in the opposite direction, such relative rotation is permitted and, as a result, rotational movement will be imparted to clutch gear 33 within the head housing 15. Rotational movement is not transmitted to handle 11, however, because of the slipping action of the clutch occasioned by the fact that the torque load limit is exceeded when the wrench is normally gripped and operated in its oscillatory mode.
While in the foregoing I have disclosed an embodiment of the invention in considerable detail for purposes of illustration, it will be understood by those skilled in the art that many of these details may be varied without departing from the spirit and scope of the invention. | An improved speed handle ratchet wrench that can be used in either of two distinct modes of operation to rotate the drive member at the head end of the wrench. A clutch assembly disposed within the head housing transmits axial rotation of the handle to the drive member below a selected torque load level during the first operating mode, and prevents handle rotation under normal circumstances in response to oscillation of the handle in the second operating mode. The clutch assembly includes a clutch sleeve and a pair of coaxial clutch member having frusto-conical surfaces engagable with the inside surfaces of the sleeve. Torque adjustment is achieved by moving the coaxial members towards or away from each other to vary the frictional engagement between such members and the sleeve. | 1 |
FIELD OF THE INVENTION
The present invention is generally related to an automatic focusing mechanism, and more particularly related to an automatic focusing mechanism driven by an electromagnetic force.
DESCRIPTION OF THE RELATED ART
Automatic focus is a technique widely used in many imaging equipments such as cameras, camcorders, mobile-telephones and devices with video capturing capabilities. Since devices with portability capability are increasingly desired by users, the trends of an automatic focusing mechanism in such devices are moving towards smaller form factor and lighter weight. The automatic focusing mechanism in a conventional method generally utilizes a motor to control the lens group to move along an optical axis so as to change the distance between the lens group and the sensor (such as CCD or CMOS). However, because of the size of the motor, it is difficult to further reduce the size of the focusing mechanism.
There are many automatic focus techniques proposed without using a motor diver, such as using an electromagnetism force inducing from an electromagnetic field to drive the lens group. FIG. 1 duplicates a drawing in a Chinese patent publication No.: CN1203362C that includes a sensor 11 , a base plate 12 , a sensor housing 13 , a light filter 14 , an elastic part 16 , lens 17 , a lens vane 18 , a winding coil 19 and a magnet 20 . The wire at the outside of the elastic part 16 is connected to the electrical wire so as to provide an electric current. The current via the elastic part 16 feeds into a roll-type coil twisting onto the outside of lens vane 18 . The electromagnetism force can be produced by the interaction between the magnetic field inducted from the coil and the magnet 20 connected around the coil 19 or the inherent field by the permanent magnetic, then forcing the lens vane 18 to move up or down. Thus, the distance between the lens 17 fixed on the lens vane 18 and image sensor 11 can be adjusted.
The prior art as described above takes out the motor and utilizes the electromagnetism force to move the lens group, so it may reduce the size of the focusing mechanism at a certain level. However, it needs a fixed mechanism that combines the lens group and the magnet or coil so as to drive the lens moving in synchronization. To keep the optical path unblocked, the fixed mechanism could only be positioned on the side of the lens group, which not only increases the difficulty to assemble such a fixed mechanism but also makes it difficult to further reduce the size of the focusing mechanism.
SUMMARY OF THE INVENTION
This section is for the purpose of summarizing some aspects of the present invention and to briefly introduce some preferred embodiments. Simplifications or omissions in this section as well as the title and the abstract of this disclosure may be made to avoid obscuring the purpose of the section, the title and the abstract. Such simplifications or omissions are not intended to limit the scope of the present invention.
Generally speaking, techniques for automatic focusing using an electromagnetic force are disclosed. An automatic focusing mechanism comprises a plurality of lenses and an image sensor disposed along an optical axis, an electromagnetic driving device for generating an electromagnetic force to drive the image sensor to move along the optical axis, and a position-limited device for limiting the movement of the image sensor along the optical axis. The image sensor is driven by the electromagnetic force and moved along the optical axis, and the distance between the lenses and the image sensor is properly adjusted, thereby realizing automatic focusing.
The present invention may be implemented in various forms including a method, an apparatus or a part of a system. According to one embodiment, the present invention is an automatic focusing mechanism comprising: a lens group arranged along an optical axis; an image sensor arranged along the optical axis; an electromagnetic driver for inducing an electromagnetic force to drive the image sensor to move along the optical axis; and a spacing restrictor for limiting an movement of the image sensor along the optical axis.
One of the objects in the present invention is to make it possible to further reduce the size and weight of the focusing mechanism.
Another one of the objects in the present invention is to provide low noise in the operation of automatic focus.
Yet another one of the objects in the present invention is to provide a simple mechanism movement and fast speed in focusing adjustment.
Other objects, features, and advantages of the present invention will become apparent upon examining the following detailed description of an embodiment thereof, taken in conjunction with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which:
FIG. 1 is a perspective view of an automatic focusing apparatus according to a prior art system;
FIG. 2 is a block diagram of an exemplary auto-focus control part according to one embodiment of the present invention;
FIG. 3 is a cross-sectional view of an exemplary automatic focusing mechanism according to one embodiment of the present invention;
FIG. 4 is an exploded view of the automatic focusing mechanism of FIG. 3 ;
FIGS. 5 a and 5 b show different numbers of flexible PCBs being assembled on the automatic focusing mechanism of FIG. 3 ;
FIG. 6 illustrates different shapes of the flexible PCB of the automatic focusing mechanism of FIG. 3 ;
FIG. 7 is a cross-sectional view of an automatic focusing mechanism according to another embodiment of the present invention; and
FIG. 8 is a block diagram showing an automatic focusing algorithm used in the automatic focusing mechanism of FIG. 7 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The detailed description of the invention is presented largely in terms of procedures, steps, logic blocks, processing, and other symbolic representations that directly or indirectly resemble the operations of data processing devices coupled to networks. These process descriptions and representations are typically used by those skilled in the art to most effectively convey the substance of their work to others skilled in the art. Numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will become obvious to those skilled in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, components, and circuitry have not been described in detail to avoid unnecessarily obscuring aspects of the present invention.
Reference herein to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Further, the order of blocks or steps in process flowcharts or diagrams representing one or more embodiments of the invention do not inherently indicate any particular order nor imply any limitations in the invention.
Referring now to the drawings, in which like numerals refer to like parts throughout the several views. FIG. 3 shows a cross-sectional view of an exemplary automatic focusing mechanism according to one embodiment of the present invention. FIG. 4 shows the corresponding exploded view of the automatic focusing mechanism of FIG. 3 . The embodiment in FIG. 3 or 4 includes a lens group 1 , a lens sleeve 2 , an image sensor 3 , a PCB (printed circuit board) substrate 4 , a flexible PCB 5 , an external PCB 6 , a drive coil 7 , a permanent magnetic 8 and a base frame 9 .
The lens group 1 is fixed inside the lens sleeve 2 . The position of the lens sleeve 2 , the external PCB 6 and the base frame 9 form a housing. In one embodiment, the lens sleeve 2 , the external PCB 6 and the base frame 9 are rigidly positioned to act like an enclosed empty cavity. An optical path passes only into such a cavity through an aperture on the front of the lens sleeve 2 . The lens group 1 and image sensor 3 are positioned along an optical axis 11 , and both of them are collimated with the aperture center. The image sensor 3 is soldered on the PCB substrate 4 , and its center is aligned with the optical axis 11 . The drive coil 7 is fixed on one side of the PCB substrate 4 but on the opposite side the image sensor 3 is assembled. The drive coil 7 also movably surrounds the permanent magnetic 8 . The flexible PCB 5 is welded between the PCB substrate 4 and the external PCB 6 respectively. One end of the flexible PCB 5 being connected to the PCB substrate 4 is connected to both the image sensor 3 and drive coil 7 so as to transmit the electrical signals of the image sensor 3 and supply a driving current to the drive coil 7 .
The flexible PCB 5 provides the function of extending the PCB substrate 4 electronically as well as keeping the position of the image sensor 3 . To prevent the center of image sensor 3 from deviating from the optical axis 11 in a focusing operation, the orientation of a resultant force from the distortion of the flexible PCB 5 should point along the optical axis 11 . This can be solved by deploying two or four flexible PCBs in a symmetrical pattern as illustrated in FIGS. 5 a and 5 b , respectively. Additionally, the center of the image sensor 3 integrated with the PCB substrate 4 and the center of the drive coil 7 should be coincided with the optical axis 11 .
The flexible PCB 5 used in one embodiment is a type of printed circuit board that provides flexibility and distortion with repeatability. Examples of such a printed circuit board is a type of flexible PCB named after Mil-P-50884-Type-1, provided by Mod-tronic Instrument Ltd. in US, and manufactured by the way of sandwiching a copper thin sheet into a polyimide layer. In one embodiment, its thickness of the flexible PCB 5 is about 0.14 millimeter. The more distortion a flexible PCB presents, the stronger the force is generated from the flexible PCB. To enhance the distortion magnitude when the PCB is pressed, the flexible PCB may be bent into a V-shape, a W-shape or a multi-pleat shape illustrated respectively in FIG. 6 . When the flexed flexible PCB is being pressed, the bending angles change, resulting in the flexible PCB being stretched or distorted thus to cause a movement.
In operation, the positions of the lens group 1 , the permanent magnetic 8 and the external PCB 6 are relatively fixed. The image sensor 3 is driven by the electromagnetic force inducted from the permanent magnetic 8 and the drive coil 7 , moving along the optical axis to achieve focusing. As shown in FIG. 2 , light signals of images pass through the lens group 1 and are focused onto the image sensor 3 . The optical image is converted to the digital image signal by the image sensor 3 , where the digital image is synchronized horizontally and vertically. Such a digital image signal is transmitted to the external PCB 6 via the flexible PCB 5 , and arrives to a central processor (such as a digital signal processor or a CPU of a PC) via other interface circuits. The central processor is configured not only directly to display the digital image signal on a display screen but also judge whether the digital imaging system is focused. If the image is out of focus, the central processor outputs a control signal which is transformed into a positive or a negative DC voltage by a direct current drive circuit and such a DC voltage will act onto the drive coil 7 . Based on the right-hand rule in electromagnetism, the coil inducts an electromagnetic field with S or N polarity whose direction is decided by the direction of the current. The interaction between the electromagnetic field and the permanent magnetic 8 can cause a force to move the image sensor 3 up and down or back and forward along the optical axis so as to adjust a distance between itself and the lens group 1 .
To balance the movement of the image sensor 3 , the flexible PCB 5 provides an elasticity force that acts as a function of counterbalance. The distortion magnitude of the flexible PCB 5 is increased with the increased electromagnetic force. The elasticity force and the electromagnetic force are balanced with each other to guarantee the image sensor 3 to be fixed at a position. At the same time, the symmetrical positions of the flexible PCBs prevent the center of image sensor 3 from deviating from the optical axis in a focusing operation. Because the current in the coil can be continuously adjusted, a high precision of optical focusing can be achieved.
FIG. 7 shows another embodiment in which one side of a spacing restrictor, a flexible film 5 ′, is connected between the PCB substrate 4 , and the external PCB 6 . Depending on an exact implementation, the flexible film 5 ′ may be made from polyester, nylon, rubber or polyamine. To prevent the center of image sensor 3 from deviating from the optical axis in a focusing operation, the orientation of the combined forces generating from the distortion of the flexible film 5 ′ should be aligned along the optical axis. Similar to the embodiment of FIG. 3 , two or four flexible film 5 ′ may be positioned around the image sensor 3 in a symmetric pattern so that the orientation of the combined forces generating from the distortion of the flexible film 5 ′ are collimated along the optical axis.
In operation, the flexible film 5 ′ is caused to be tensed or released so the center of the image sensor 3 can be located securely along the optical axis 11 . It should be noted that the flexible film 5 ′ is not to be distorted in a sense of it being bent into a V-shape, a W-shape or a multi-pleat shape. The flexible film 5 ′ is only to be stretched. Since the flexible film 5 ′ does not provide the electronic connections, a set of flexible wires 10 is provided in this embodiment to control the image sensor and to lead the image signals out therefrom. The permanent magnet 8 is fixed on one side of the PCB base plate 4 on which the image sensor 3 is settled. The coil 7 is fixed on the base frame 9 , and the permanent magnet 8 is movably mounted around the coil 7 .
In operation, the position between the lens group 1 , the drive coil 7 and the external PCB 6 are properly disposed, and the image sensor 3 is driven by the electromagnetism force inducted from the permanent magnetic 8 and the drive coil 7 , periodically oscillating along the optical axis. The magnitude of moving the image sensor 3 should cover a range that all scenes can be focused onto the image sensor 3 (e.g., between one and two focal lengths when there is a single lens in a lens group), and its oscillating period should be longer than the exposure time of the image sensor 3 to guarantee the exposure stability. In one embodiment, the oscillating period is made 100 times longer than the exposure time. The light signal is impinged upon the oscillating image sensor 3 via lens group 1 , and the image signal is generated and transmitted to the external PCB 6 via the wire set 10 , and it arrives to the central processor (such as a DSP in a digital camera or a CPU in a PC) via other interface circuitry.
In one embodiment, the drive current in this embodiment is provided with a fixed period. The movement of the image sensor 3 along the optical axis is substantially the same in each period. The central processor periodically samples and processes the received digital image signal for calculating an optimal focalized time point. FIG. 8 shows an automatic focus algorithm adopted in this embodiment, where the horizontal axis stands for time t, and the vertical axis represents the displacement s of the image sensor 3 . In the first oscillation period, the digital image signals are obtained at t=0 and other time intervals t 11 , t 12 and t 13 , respectively. Then the processor is configured to judge whether the image is a focalized one at the time nodes by a degree of the image sharpness or blurring. If the image is out of focus, the processor is configured to compute where the focalized point should be supposed to present in which time intervals among 0˜t 11 , t 11 ˜t 12 , t 12 ˜t 13 , t 13 ˜T (The image at T is similar to the one at 0). In the next oscillation period, the process reselects the digital images in narrowed range, for example, at the three moments of t 21 , t 22 , t 23 which are located near the time interval where the focusing point is likely to occur (e.g., t 11 ˜t 12 ), which is estimated from the previous period. Repeatedly judging whether the image is focused at the moment t 21 , t 22 , t 23 , the focusing point can be located in terms of the time interval. If the image is still out of focus, then the processor is configured to reevaluate the focalized point supposed to present in the time intervals t 11 ˜t 21 , t 21 ˜t 22 , t 22 ˜t 23 and t 23 ˜t 12 . Similar operation may be repeated until a reasonable focalized point and corresponding moment t v are obtained. Subsequently, the focused photograph may be taken at the t v moment in the next period.
One of the features in the focusing algorithm used in this embodiment is a one-to-one mapping relationship between the displacement of the image sensor 3 and each of the sampled moments in a period. Because of the unique structure to control the movement of the image sensor in the embodiment, this one-to-one mapping relationship is to be maintained in all periods. Hence, as long as the accurate moment t v in focus is found in a period, the focusing operation is essentially finished. It may also be noticed that there is no need to adjust the current in the drive coil by judging the defocused degree to change the distance between the lens group 1 and the image sensor. Compared with the focusing mechanism by changing the drive current, the operation of this embodiment is simple, although it needs the image sensor 3 to expose constantly or in movement. To ensure the clear imaging, the oscillating period is limited by the exposure time, so does the focusing time. This embodiment is effective with a short exposure time, such as CCD image sensor, high-speed camera or other applications without a high demand for a focusing time.
It should be noted that other focusing algorithms may be used to accomplish the focusing operation, such as exposure at each moment when the oscillating amplitude almost turns to the maximum, and changing the oscillating magnitude by altering the value of the drive current. Although in a sense this approach is similar to the embodiment of FIG. 3 , the difference is that the exposure process is operated in a static state in the embodiment of FIG. 3 while the exposure process of the embodiment of FIG. 7 is at the moment that the sensor may be still moving (the moving speed at the position of the maximum magnitude is the slowest in all movements).
As a spacing restrictor, the flexible film 5 ′ provides an elasticity force that is as a function of counterbalance from the mechanic perspective. The distortion magnitude of the flexible film 5 ′ enhances with the increased electromagnetic force. The varying process of the resultant force from the elasticity and electromagnetism force decides the movement of the image sensor 3 along the optical axis. At the same time, the symmetrical arrangement of the flexible film 5 ′ prevents the center of the image sensor 3 from deviating from the optical axis in a focusing operation.
One of the features in the present invention is that the gravitation of the image sensor 3 integrated with the corresponding accessories is much smaller than the electromagnetism force and the elastic force from the distortion of the flexible PCB 5 or the flexible film 5 ′. Therefore, the automatic focusing mechanism in the present invention would not result in an offset when the gravitation direction is not aligned with the optical axis, and the offset between the center of the image sensor 3 and the optical axis also can be avoided.
The present invention has been described in sufficient detail with a certain degree of particularity. It is understood to those skilled in the art that the present disclosure of embodiments has been made by way of examples only and that numerous changes in the arrangement and combination of parts may be resorted without departing from the spirit and scope of the invention as claimed. While the embodiments discussed herein may appear to include some limitations as to the presentation of the information units, in terms of the format and arrangement, the invention has applicability well beyond such embodiment, which can be appreciated by those skilled in the art. Accordingly, the scope of the present invention is defined by the appended claims rather than the forgoing description of embodiments. | An automatic focusing mechanism comprises a plurality of lenses and an image sensor disposed along an optical axis, an electromagnetic driving device for generating an electromagnetic force to drive the image sensor to move along the optical axis, and a position-limited device for limiting the movement of the image sensor along the optical axis. The image sensor is driven by the electromagnetic force and moved along the optical axis, and the distance between the lenses and the image sensor is properly adjusted, thereby realizing automatic focusing. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority of U.S. Provisional Patent Application No. 61/300,442 filed on Feb. 1, 2010, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a heat transfer device useful for removing the heat generated from a heat source. The present invention provides structures comprising anisotropic thermal conducting substance in a heat transfer device, thereby directing the heat away from the heat source at high efficiency.
[0004] 2. Description of the Prior Art
[0005] A typical heat transfer devices such as the heat sink for the cooling of an electronic device comprise metal structure for directing the heat from a heat source to a larger distributed area for dissipation. The heat conducting materials are typically isotropic that direct heat in all directions according to the temperature gradient. In such devices and structures, the heat transfer is limited by the temperature gradient according to the thermal distribution of the isotropic thermal material. In a heat transfer device comprising a heat pipe, a cooling substance and an associated structure for directing the cooling substance are provided. Multiple phases with phase transitions of the cooling substance combined with capillary action provide a directed heat transfer, thereby improving the heat removal and the efficiency to direct the heat to a longer distance away from the heat source. In such devices, the coexistence of two phases and the channeling of the cooling substance creates a temperature distribution that does not follow the isotropic temperature gradient, and the heat transfer efficiency may exceed the isotropic thermal conduction. However, various boundaries and interfaces, the interaction between the container and the cooling substance are still limited by the isotropic thermal conduction. Such limitation is a major obstacle in improving the heat transfer efficiency.
[0006] As the technology drives to continue scaling down in size and scaling up in capacity, the advanced CPU, high speed mobile transmitters, CPV, high power or high density LEDs, are operating at a power density exceeding 100 W/cm2. In some applications, a thermal management to handle a power density exceeding 300 W/cm2 is in critical need. The temperature is becoming a critical limiting factor for the electronic device to continue to scale down in size or scale up in capacity. The present invention provides structures and methods to improve the efficiency and rate of heat transfer applicable for the cooling of a heat source.
SUMMARY OF THE INVENTION
[0007] The present invention provides a thermal transfer device having anisotropic thermal conducting substance disposed at various face to enhance the directional heat transfer and provide a high heat exchange efficiency.
[0008] An object of the present invention is a thermal transfer device having anisotropic thermal conducting substance along the surfaces of both sides of a heat absorption layer. On one side, the surface is in contact with a cooling substance. On the other side, the surface is made to contact a heat source.
[0009] The present invention further provides structures comprising anisotropic heat conducting substance on both sides of the heat absorption layer.
BRIEF DESCRIPTION OF THE DRAWING
[0010] FIG. 1 a is schematic diagram of a preferred embodiment of the present invention.
[0011] FIG. 1 b is schematic diagram of a preferred embodiment of the present invention.
[0012] FIG. 1 c is schematic diagram of a preferred embodiment of the present invention.
[0013] FIG. 2 is a schematic diagram of a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] A micro structure in this description refers to a structure having features on the order of a micrometer or smaller. Similarly, a nano structure comprises features on the order of a nano meter or smaller. An example of a micro structure is micro pores. A nano tube is an example for a nano structure, and is also a micro structure.
[0015] An anisotropic heat (or thermal) conducting substance provides a higher thermal conductance in one direction, hereinafter referred to as the longitudinal direction, than in at least a direction perpendicular to such direction. The direction of higher thermal conductance of an anisotropic thermal substance is herein referred to as the longitudinal direction, and the directions perpendicular to a longitudinal direction is hereinafter referred to as transversal directions. An anisotropic thermal conducting substance may possess a single longitudinal direction, such as in carbon nanotubes where the longitudinal direction is along the tube, or multiple longitudinal directions, such as in graphite where the direction of higher thermal conductance may be any direction along the graphite plane.
[0016] The present invention is herein described in detail in reference to the drawings.
[0017] FIGS. 1 a to 1 c illustrate a preferred embodiment of the present invention, wherein 100 is a heat transfer device comprising an absorption section 110 and a dissipation section 120 , wherein the absorption section comprises an absorption layer 101 having a first face 102 and a second face 103 on opposite sides of said absorption layer 101 ; wherein said first face is made for contacting a heat source 150 . The dissipation section 120 is to be maintained in contact with a temperature lower than the heat source so that the heat is removed from the dissipation section. The first face 102 is so prepared that a heat source 150 of which the heat is to be removed by the device 100 may be attached to the surface of 102 , either directly or with an intermediate structure or layer between 150 and 102.
[0018] The heat transfer device 100 provides a means 105 for directing a cooling substance to or away from said absorption layer, and to directed said cooling substance to or away from the dissipation 120 ; as illustrated in FIG. 1 , the open space 105 provides a path for the cooling substance to move from the absorption section 110 to the dissipation section 120 . Since the absorption section 110 continues to absorb heat from the heat source 150 , a distribution and pressure difference is maintained between the absorption section 110 and the dissipation section 120 , providing a driving force to move the cooling substance away from the absorption section 110 .
[0019] In FIG. 1 , 106 is a structure comprising an anisotropic thermal conducting substance. The anisotropic thermal conducting substance provides a substantially higher thermal conductance in one direction (the longitudinal direction) than at least a transversal direction. Structure 106 is placed along the surface of second face 103 of the heat absorption layer 101 , and is in contact with the second face 103 . A preferred embodiment of the anisotropic thermal conducting substance comprises microstructures such as graphite and carbon nano structures, or a combination of the micro and nano structures. A preferred embodiment for the structure 106 comprises a layer of the anisotropic thermal conducting substance. The layer may be fabricated by directly depositing onto the surface of the face 103 , or by attaching a preformed film or slab onto the surface of 103 . Another preferred embodiment of structure 106 comprises a plurality of leaves or blades, wherein each leave or blade comprises a composite of the anisotropic thermal substance.
[0020] The anisotropic thermal conducting substance provides a substantially higher thermal conductance in one direction (the longitudinal direction) than at least one of the transversal directions. In carbon nano tubes, the thermal conductance alone the tube is substantially higher than all the transversal directions. In graphite, the thermal conductance is substantially higher along the graphite plane. In such embodiment comprising graphite, the longitudinal direction may be a selected direction parallel to the graphite plane, and the thermal conduction is lower in the direction perpendicular to the graphite plane.
[0021] In a preferred embodiment, the micro or nano structures, such as graphite or carbon nano tubes, are preferentially arranged to be substantially perpendicular to the surface of the second face 103 .
[0022] A preferred embodiment of the anisotropic thermal conducting substance comprises one of the group of graphite, carbon nano tube, graphene, charcoal layer, charcoal sheet, similar tubular or layered, or sheet of carbon structures, or aforementioned substance containing partial substitutes for carbon.
[0023] The anisotropic thermal conducting substance may have one direction of higher thermal conductance as in carbon nanotubes. In such case, a structure arranged to having the longitudinal direction substantially perpendicular to the surface of contact is represented by 106 in both FIGS. 1 a and 1 b . Where the anisotropic thermal substance has more than one direction of higher thermal conductance, such as in graphite where the thermal conductance is higher along the graphite plane, FIGS. 1 b and 1 c represent a preferred embodiment of the structure 106 , wherein the graphite plane is arranged parallel to the direction of the path connecting the absorption section and the dissipation section.
[0024] The directional thermal conduction resulted from the design of the anisotropic thermal conduction structure at the internal wall of the heat transfer device enhances the adiabatic transfer of the cooling substance back to the heat absorption region and toward the dissipation region, thereby enhancing the cooling and dissipation efficiency.
[0025] FIG. 2 illustrates another preferred embodiment of the present invention wherein a structure 212 comprising an anisotropic thermal conducting substance is placed along the first face 102 of the heat absorption layer 101 . The anisotropic thermal substance provides a thermal conductance substantially higher in one direction (longitudinal) than in at least a transversal direction. In a preferred embodiment, the anisotropic thermal conducting substance in the structure 212 is arranged in a manner that the longitudinal direction with substantially higher thermal conductance is substantially perpendicular to the surface of said first face 102 .
[0026] Another embodiment of the present invention provides structure or layer in contact with at least one of the two faces 102 and 103 of the absorption layer, wherein the structure or layer contains carbon nano-structures or graphite.
[0027] The structure or layer comprising anisotropic thermal conducting substance may be formed directly onto the surface of the faces 102 and 103 . The method of formation includes gas or liquid phase chemical deposition, such as CVD, electrolytic coating, and MOCVD. In one embodiment of the direct formation embodiments, the section of the layer forming the absorption or dissipation section, or the entire absorption or dissipation section is placed in a chemical ambient for direct deposition to the designated surfaces. Examples of direct deposition to the designated surface include the deposition of carbon nano tubes in MOCVD.
[0028] In another embodiment, the anisotropic thermal substance is provided in a layer of pre-form, wherein the pre-form is attached to the surface where needed to provide a highly directional thermal conduction or insulation whichever is preferred.
[0029] In one preferred embodiment, the structure comprising an anisotropic thermal conduction substance is a layer of high carbon-containing substance such as graphite and carbon nanotubes. It is conceivable that the present invention applies to similar structures and substance wherein some of the carbon atoms are replaced by other elements such as metals.
[0030] Another embodiment of the present invention provides a heat transfer device comprising a heat absorption layer wherein both sides of such layers comprise a plurality of micro or nano-structure attached thereto; said micro or nano structure having a dimension substantially greater in one direction (longitudinal) than in a transversal direction, and wherein the thermal conductance is substantially higher along the longitudinal direction than a transversal direction.
[0031] A preferred embodiment of the heat transfer device according to the previous paragraph provides an arrangement wherein the longitudinal direction is substantially perpendicular to the surface of the absorption layer or dissipation layer.
[0032] Another preferred embodiment provides a heat transfer device according to above description wherein the micro or nano-structure comprises a composite containing more than fifty percent of carbon. The carbon-containing substance may have part of the carbons replaced by substitutes such as metallic atoms.
[0033] Although various embodiments utilizing the principles of the present invention have been shown and described in detail, it is perceivable those skilled in the art can readily devise many other variances, modifications, and extensions that still incorporate the principles disclosed in the present invention. The scope of the present invention embraces all such variances, and shall not be construed as limited by the number of elements, specific arrangement of groups as to rows and column, and specific circuit embodiment to achieve the architecture and functional definition of the present invention. | An isotropic thermal conducting material are arranged in a heat dissipating device to create directional adiabatic heat transfer. In one embodiment, a preferential heat conduction is provided between a heat source and an absorption layer, an absorption layer and a cooling substance, and a cooling substance and a dissipation layer. Structures are further provided to create adiabatic channeling between an absorption and a dissipation. | 5 |
This is a continuation division of application Ser. No. 08/021,594, filed Feb. 24, 1993, now abandoned.
DESCRIPTION
The invention relates to an apparatus and a process for classifying the contents of non-disposable beverage bottles and containers. particularly for food industry products, but also those of the chemical industry. Apart from the problem solved in U.S. patent application No. 905,470 now U.S. Pat. No. 5,305,887 and German patent application P 4203274.1 of pollutant identification and classification linked with the sorting out e.g. from filling lines of bottles/containers contaminated with pollutants, the economic aspect is of major significance. It requires that the products belonging to the particular non-disposable bottle/container do not lead to a discharge. In the beverage or drinks industry this means that e.g. petrol or diesel-contaminated bottles/containers are discharged, but that drink contents such as e.g. citrus flayours or harmless fermentation products such as e.g. ethanol do not lead to a discharge. Thus, e.g. the content limonene, which is in part contained in higher concentrations in soft or sweet drinks is detected as a "good" substance and this also applies with regards to ethanol, provided that the concentrations are relatively low in accordance with the fermentation processes taking place.
However, to make the problem posed more difficult the presence of ethanol must lead to a discharge if the concentrations are so high that it is not possible to exclude that these are not pure fermentation products, but instead detergents or spirit, which can lead to flavour falsifications on refilling the bottle/container with the new product. The same applies in connection with the contamination with cleaning agents which, for odour concealment purposes, are mixed with high limonene percentages and due to the cleaning chemical constituents must be removed from the process.
The considerable complication of the set problem compared with U.S. patent application No. 905,470 is inter alia that above a given concentration a substance classified as "good" must lead to a "bad" characterization and therefore to a discharge.
WO 88/00862 discloses processes for determining contaminated and uncontaminated containers, which do not give satisfactory results inconnection with the above set problem.
For solving this problem according to the invention the sums are formed from positive functions of differences between associated ordinate values of the actual on-line measured spectra and those in the memory and the substance having the smallest sum value or total is considered to be detected.
According to a preferred development the "good" and "bad" substances identified by special "fingerprints" according to U.S. patent application No. 905,470 are in each case detected as belonging to one or other category and thresholds are used as a criterion for non-discharge or discharge. These thresholds are chosen in such a way that for concentrations above or below preselected concentrations a discharge does or does not take place.
In the special case of citrus flayours, e.g. limonene this means that according to the invention firstly the citrus component is detected as a "good" substance and in the next process stage detection takes place to establish whether the concentration is below a threshold S 1 , which is e.g. so chosen that it is not exceeded for soft drinks of all types and does not lead to a discharge.
However, if the limonene concentration is above S 2 , an additional check is made according to the invention to establish whether e.g. limonene-mixed cleaning agents are present. On exceeding a threshold S 2 , which is below the limonene concentration of standard cleaning agents, the particular bottle/container is discharged in accordance with the present invention. The same applies e.g. for ethanol, which is formed in small concentrations during the fermentation of soft drinks and remains in the drink filling line when below the threshold S 3 , but on exceeding the threshold S 4 leads to a discharge, because e.g. spirit, highly concehtrated alcoholic liquors, wine, etc. can be present as ethanol-containing, flavour-falsifying substances.
To be able to carry out the classification according to the invention with a probability bordering on certainty in the constituent groups:
______________________________________"true pollutants", e.g. acetone, petrol, diesel, methanol, xylene, benzene, toluene, etc. and mixtures thereof,"camouflaged pollutants" such as limonene-mixed cleaning agents, ethanol-mixed detergents, etc."bottle/container-specific products" such as e.g. soft drinks, mineral waters fruit juices, etc.,______________________________________
According to the invention effective measures are provided for selective substance detection. In addition, the invention proposes processes and apparatuses for the concentration determination of the aforementioned components, i.e. for precise classification into "bottle/container-specific products" below the threshold S 1 , S 3 and including fermentation products thereof and "true" or "camouflaged" pollutants above the threshold S 2 , S 4 .
Building up on the technical teaching of U.S. patent application No. 905,470, the pollutant detection is decisively improved according to the invention, in that the substance-specific spectra obtained by spectral processes in the ultraviolet, visible, infrared and microwave spectral ranges, undergo a novel evaluation process. The latter is based on the comparison of the actual spectra measured on a bottle/container sample with spectra filed in a memory taking place in such a way that according to the invention a comparison is made to establish whether the actually measured and stored values coincide as regards:
the positions of the maxima and minima on the wavelength scale, the half-intensity widths, i.e. the wavelength intervals at half the height,
the base widths, i.e. the wavelength intervals within which there is a spectrum,
the amplitude ratios of the maxima present,
the amplitude ratios of the minima present,
the amplitude ratios of maxima and minima.
As a result of these measures it is ensured that the necessary on-line evaluation is made possible for the first time with the high bottle capacities of up to 50,000 bottles per hour in the drinks industry using a single sensor system and at the same time with an acceptable computing expenditure, i.e. greatly reduced computation activity.
As the incorrect discharge or elimination of bottles, i.e. without any need for the same, leads to additional manual work in the drinks industry causing inadmissible additional costs, in order to avoid these costs the invention provides further measures which, in conjunction with the aforementioned measures, increase to almost 100% the reliability of selective substance detection. According to the invention the spectra are scanned in point pairvise manner and the following processes are used in the comparison between the actually measured and stored spectra:
determination of the sum of the standard deviations of all the individual points,
determination of the sum of the differences of all the individual points.
The substance within the numerous stored substances is considered to be detected in which the above quantities have a minimum and in which the maximum is below a number to be set by the plant operator.
According to a further development of the invention the quotients between the actual and the stored spectra are formed and the resulting quotient function evaluated.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in greater detail hereinafter relative to the drawings, wherein show:
FIG. 1 is the different limonene concentrations in a soft drink or a domestic cleaning agent with the thresholds S 3 and
S 4 .
FIG. 2 is the different ethanol concentrations in a fermented soft drink or a high percentage alcoholic liquor with the thresholds S 3 and S 4 .
FIG. 3 is the selective substance identification over selected spectral parameters.
FIG. 4 is the selective substance identification over the sum of the standard deviations and the selective substance identification over the sum of the differences.
FIG. 5a is a quotient formation between the spectra of different substances.
FIG. 5b is a quotient formation between spectra of identical substances.
FIG. 6 is a diagram of the overall arrangement of the system according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a spectral distribution of the gaseous phase of limonene in a multipurpose cleaner (1) and a soft drink (2) obtained with an arrangement according to U.S. patent application No. 905,470. It can be seen that the limonene concentration in the multipurpose cleaner (1) is much higher than in the soft drink (2). As a result of the inventive introduction of the thresholds S 1 (3) and S 2 (4) limonene-camouflaged pollutants (1) can be discharged, whereas limonene-mixed soft drinks (2) can remain in the bottle/container. The threshold S 1 (3) is such that it is above the limonene concentration of all soft drinks. The threshold S 2 (4) is fixed in such a way that the limonene concentration of the particular cleaning agent (1) etc. is above the threshold S 2 (4). This also applies with respect to the ethanol concentrations of a fermented soft drink (5) and a high percentage alcoholic liquor (6) shown in FIG. 2. As the liquor is above the threshold S 4 (7), the associated bottle is discharged. However, the bottle with the fermented soft drink remains in the filling line, because the maximum ethanol concentration (5) is below the threshold S 3 (8).
FIG. 3 shows the substance identification according to the invention over selected spectral parameters using the example of the pollutant pentachlorophenol. For this purpose a check is initially made as to establish which substance, contained in a library, has maximum (9,10,11,12) or minima (13,14) at the same wavelengths as the actually determined substance. A check is then made as to whether the ratios of the relative maxima (15,16,17,18,19), e.g. (15):(16), (15):(17), (15):(18), (15):(19), (16):(17), (16):(18), (16):(19), (17):(18), (17):(19), (18):(19) coincide within certain predeterminable limits with the quotients filed in the memory. Finally a check is made as to whether the ratios of the amplitudes (20,21) of the minima, i.e. (20,21) in the predetermined limits coincide with the stored quotients. To further increase identification certainty the corresponding ratios can be formed from the minimum and maximum amplitude values. Further characteristic features can be gathered from the half-intensity widths (22,23) and the base width (24), e.g. at 10% of the maximum amplitude.
According to the invention and FIG. 4 the sum of the standard deviations or the sum of the absolute values of the differences between the actual spectrum (24) and the spectra (25) filed in the memory is formed. FIG. 4 shows as an example a spectrum (25) for limonene from the memory as compared with the actually measured limonene spectrum (24). The formation of the sum of the standard deviations ##EQU1## sum of the differences ##EQU2## of both spectra in both cases leads to minimum values of the sums or totals compared with the cases in which spectra of different substances are compared and in which:
E 76 =δ.sub.ι ·1·n.sub.ι =extinction
δ.sub.ι =absorption coefficient
1=optical wavelength
n.sub.ι =number of pollutant molecules/cm 3 .
FIG. 5a shows the result of quotient formation (39) between spectra of different substances, in this case benzene (37) and acetone (38), FIG. 5b gives the corresponding result of quotient formation of a spectrum from the memory (41) and an actual spectrum (42) for the same substances, such as e.g. limonene. According to the invention, for simple evaluation purposes the total of the individual values of the quotient spectrum is formed, the maximum sum characterizing the identical substance.
The overall system according to the invention is shown in FIG. 6. A source (27) for producing electromagnetic radiation in the ultraviolet, infrared and microwave range irradiates the bottle (31)/container to be tested in accordance with the beam path (28) or the beam path of the scattered or reflected beam (33). The changes in the spectral composition of the radiation brought about by the contents (32) or the pollutants are analysed by the spectrometer modules I,II (30,29). The resulting spectra are comDared on-line by a signal processor (35) with the known spectra stored in a spectrum memory (34). If the marginal conditions for a bottle/container discharge are fulfilled, by means of an instruction to the machine control (36) the discharge mechanism (37) is activated and the bottle is discharged. | The invention relates to a process and an apparatus for the selective on-line identification and distinguishing of pollutants and contents in bottles/containers in filling systems in the beverage or drinks industry using the absorption, reflection and scattering of electromagnetic waves from the UV to the microwave range, characterized in that characteristic value pairs/ranges of wavelength and amplitude are used for identification and distinguishing. | 6 |
BACKGROUND OF THE PRESENT INVENTION
This invention relates to a disk information recording medium. More particularly, the present invention relates to an information recording disk, which limits the eccentric distance between the center position of a positioning signal for an information convertor and the center position of rotation of an information recording disk and is suitable for positioning highly accurately and at a high speed the information convertor, to its production method and to an information recording apparatus using the information recording disk.
When information is recorded or reproduced by positioning a rotary magnetic disk and a radially moving information convertor, the information convertor must be positioned highly accurately to a desired information track. The positioning method of the information convertor has changed from an early open loop method to a closed loop servo method using a positioning signal. To obtain still higher accuracy, attempts have been made, recently, to dispose the positioning signal on the recording track, or very close to it on the surface on which the information is to be recorded and reproduced. The positioning signal is detected by the information convertor itself, or a position reference detector disposed on the information convertor, or very close to it.
In optical disk apparatuses such as a compact disk (CD), for example, tracking grooves are formed on the recording surface and information pits are formed on, or in the proximity of, the grooves. The information convertor is positioned to this tracking groove and records or reproduces the information pit at a predetermined position.
In magnetic disk storage, an apparatus for accomplishing a high track density uses a positioning signal at a predetermined angle position of each recording track, detects this positioning signal by a magnetic head for recording and reproducing the information, and positions the magnetic head to the recording track by use of this detection signal, as disclosed, for example, in Japanese Patent Publication No. 54872/1982.
SUMMARY
In the optical disk apparatus, for example, reproduction or recording/reproduction of the information on the optical disk is onducted at present by use of one information convertor. For this reason, the eccentric distance between the information recording track and the rotary spindle of the disk has not been a great problem. However, as the information capacity becomes greater, it will become necessary to fit a plurality of information recording surfaces to the same rotary spindle and to record and reproduce the information by a plurality of information convertors which are moved integrally on the same moving mechanism. In this case, since the positioning signal on each information recording surface is formed at the time of production of the positioning information recording disk, these positioning signals have large eccentric distances between them. When the information convertor is electrically switched to record/reproduce the information on the different recording surfaces, the eccentric distance described above must be corrected and the switching time is long. Furthermore, if the angle position of the information recording start point on each information recording surface is different, a waiting time until the information convertor and the information recording disk reach the desired rotating angle position is further necessary.
If the rotating speed of the information recording disk becomes high, the difficulty of following, with the eccentric distance described above, becomes great even in the conventional apparatus where one information convertor is used for one surface, and the drop of following accuracy occurs in the information recording track.
In the recording disk apparatus, the positioning signal has been recorded conventionally by a magnetic head of a write apparatus for the positioning signal after fixing the disk to the spindle, even where the positioning signal is disposed on each information recording surface. In this case, the eccentric distance of the positioning track on each information recording surface can be reduced but a long period of time is necessary for recording the positioning signal. Particularly when the track density becomes great and the total number of tracks increases, there occurs the problem that the information write time becomes extremely long. On the other hand, Japanese Patent Laid-Open No. 280026/1986 discloses a protecting pattern of the magnetic disk surface and also a positioning pattern. In this case, since the positioning signal is formed before the magnetic disk is fixed to the spindle, the difficulty of track following for each information recording surface is a problem in the same way as in the case of the optical disk apparatus described already.
It is an object of the present invention to eliminate the write time of the positioning signal after the assembly of the recording disk to an information recording apparatus and reduce the waiting time at the time of switching by an information convertor.
The objects of the present invention described above can be accomplished for an information recording disk by forming a substrate fixing position reference with a predetermined positional relationship with respect to a positioning signal of an information convertor on the information recording disk, at the time of production, and arranging this substrate fixing position reference of the information recording disk in a predetermined positional relationship with respect to the spindle of the information recording apparatus.
In an information recording disk of the type which obtains a positioning signal of an information convertor by the change of a surface shape or a material on the information recording surface of a disk substrate, the present invention provides an information recording disk characterized in that the eccentric distance between the center of rotation of the positioning signal and the center position of the inner or outer diameter of the disk substrate is made to be smaller than half the repeating unit length of the positioning signal of the information convertor in a radial direction.
In the information recording disk of the present invention, the positioning signal of the information convertor is provided to the front and reverse surfaces of the disk substrate and their eccentric distances from the center position is made to be smaller than half the repeating unit length of the positioning signal of the information convertor in the radial direction.
In the information recording disk of the present invention, the start position of the positioning signal of the information convertor in the circumferential direction is preferably made to be coincident on the front and reverse surfaces of the disk substrate within 10 μm.
In the information recording disk of the present invention, the position reference representing the position of the positioning signal of the information convertor in the radial direction is provided on the same plane as the information recording surface. The position reference for aligning the position in the radial direction or the position reference for aligning the rotation angle position in the circumferential direction is preferably disposed on the inner diameter portion or outer diameter portion of the disk substrate, respectively, and these position references can be accomplished by disposing at least one notch on the inner or outer peripheral edge portion of the disk substrate, for example.
In a production method of an information recording disk for obtaining a positioning signal of an information convertor on an information recording surface of the disk substrate by the change of a surface shape or a material, the production method of the present invention comprises forming a position reference for position alignment for either one, or both, of the position in the radial direction and the position of a rotating angle in the circumferential direction on the inner or outer diameter of the disk substrate, supporting a mask for fixing the positioning signal to the information recording surface, and aligning the corresponding position reference of the mask for fixing the positioning signal with the position reference in the radial direction and with the position reference of the rotating angle in the circumferential direction so that the eccentric distance between the center position of the inner or outer diameter of the disk substrate and the center position of the positioning signal is made to be smaller than half the repeating unit length of the positioning signal of the information convertor in the radial direction.
In the production method of the information recording disk, the information recording disk of the present invention can be produced by the steps of forming a notch or notches on either one, or both, of position alignment and angle alignment of the positioning signal for positioning the information convertor on the inner or outer diameter edge portion or portions of a disk blank leaving a finish allowance with respect to a final dimension, positioning the disk blank to the spindle of a rotary working machine having a position alignment portion corresponding to the notch for angle alignment of the disk blank by use of the rotary working machine so that it has a predetermined relation with the spindle, and conducting a surface finish of the inner and outer diameter edge portions of the disk blank.
In the production method of the information recording disk of the present invention, the information recording disk can be produced by the steps of forming a notch or notches on either one, or both, of position alignment and angle alignment of the positioning signal for the information convertor on the inner or outer diameter edge portion of a disk blank while leaving a finish allowance with respect to a final dimension, positioning the disk blank to the spindle of a rotary working machine having a position alignment portion corresponding to the notch/notches for angle alignment of the disk blank by use of the rotary working machine so that it has a predetermined relation with the spindle, and conducting a surface finish of the information recording surface of the disk blank.
Furthermore, the present invention includes an information recording apparatus for recording and reproducing information by fixing at least two information recording disks of the present invention to the same spindle, which includes making the eccentric distance of the positioning signal of the information convertor on the information recording surface of each of the information recording disks smaller than half the repeating unit length of the positioning signal of the information convertor in the radial direction.
In the information recording apparatus of the present invention, the error of the rotation start position of the positioning signal of the information convertor on the information recording surface of each information disk is preferably below 20 μm.
The information recording of the present invention includes positioning a positioning track on the information disk surface to the center of an information disk holding portion with an error smaller than half the repeating unit length of the positioning signal of the information convertor in the radial direction by notches on the inner diameter edge portion of the information recording disk and projections disposed on the information recording disk holding portion to correspond to the notches.
The information recording apparatus of the present invention includes a cylindrical hub for supporting the information recording disks, at least one projection formed on the surface of the cylindrical hub in parallel with the axis of rotation and aligning the horizontal position by biasing the notch at the inner diameter portion of the plurality of information recording disks to the projection of the cylindrical hub.
Furthermore, the information recording apparatus of the present invention includes positioning accurately the angle positions of the positioning tracks of the plurality of information disks in the circumferential direction by the notches of the inner diameter edge portions of the information recording disks and the projections of the cylindrical hub corresponding thereto, and preferably includes biasing the projections of the cylindrical hub to the notches, disposed at substantially the opposite positions to the notches by use of a flexible member such as a leaf spring.
In the information recording disk of the present invention which holds a positioning signal of an information convertor on the information recording surface of a disk substrate by the change of a surface shape or a material, the eccentric quantity between the center of rotation of the positioning signal and the center position of the inner or outer diameter of the disk substrate is preferably smaller than half the repeating unit length of the positioning signal of the information convertor in a radial direction by use of a fixing position reference of the disk substrate having a predetermined relation with the center of the position reference track on the information recording disk. Accordingly, the information convertor can be positioned rapidly to the position of a target recording track.
In the recording disk apparatus, having a carriage that moves a plurality of information converters simultaneously, it is necessary to consider according to the present invention the difference in eccentric distances of the positioning signal center of symmetry among information carrying surfaces (including recording disks having information carrying surfaces on opposed surfaces of a disk). In this case, it is necessary to select information recording disks having information carrying surfaces where the maximum eccentric distance among positioning signal centers of symmetry of said information carrying surfaces is smaller than half the repeating unit length of the positioning servo signal means in the radial direction and to fix the recording disks on the recording apparatus.
To omit the selection process before fixing recording disks on the recording apparatus, recording disks having the eccentric distance between the positioning signal center of symmetry from the center of rotation smaller than a quarter of the repeating unit length of the positioning servo signal means in the radial direction should be made in the manufacturing process of the recording disks.
In the recording disk apparatus, having a carriage that moves a plurality of information converters independently from each other, it is not necessary to consider the difference in eccentric distances of positioning centers of symmetry among information carrying surfaces. In this case, the merit of the present invention in making the eccentric distance between positioning signal centers of symmetry from the center of rotation smaller than half the repeating unit length of the positioning servo signal means in the radial direction is still attainable.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects, features and advantages of the present invention will become more clear from the following detailed description of a preferred embodiment, shown in the drawing, wherein:
FIG. 1 is a schematic view showing the structure of a magnetic disk illustrating an Embodiment of the present invention;
FIG. 2 is an enlarged view of a portion A shown in FIG. 1;
FIG. 3 is a schematic view showing the cross-sectional shape of the recording zone of the magnetic disk, taken along dotted line III--III in the radial direction of the disk shown in FIG. 2;
FIG. 4 is a flow chart showing the production steps for the magnetic disk of the present invention;
FIG. 5 is a schematic view showing the magnetic disk of the present invention fixed to a hub of a recording apparatus;
FIG. 6 is a schematic view showing the magnetic disk of the invention and another example of fixing to the hub;
FIG. 7 is a schematic view showing the magnetic disk of the invention and another example fixing to the hub;
FIGS. 8(a) and (b) are schematic views showing the magnetic disks of the invention and another hub fixing method;
FIG. 9 is a schematic view showing another example of the servo information of the present invention and;
FIG. 10 shows a magnetic disk storage that employs the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows the information recording surface of the magnetic disk 10 illustrated in this embodiment, by way of example. Recording tracks 20 are formed on the information recording surface within a recording zone 24, with a track pitch of 10 μm, and concentrically with one another with a predetermined gap between them. Each recording track 20 is alternately composed of servo sectors 22 and data sectors 21 in the clockwise direction from an index line 23 as the reference of the start of recording. In this embodiment, one track circumference consists of 17 sets of servo sectors 22 and data sectors 21. Four notches 31, 32, 33 and 34 are formed at an inner diameter portion 30 having a radius of 20 mm.
FIG. 2 is an enlarged view of the portion A of FIG. 1. In the data sector 21, the recording tracks 20 are formed 7 μm wide with a predetermined 3 μm wide gap in such a manner as to interpose track separators 20a between them. The index line 23 consists of patterns in the radial direction having an equal angular gap of 5 μm wide. Only three patterns are shown in FIG. 3. The servo sector 22 consists of servo information 22a and servo separators 22b for separating the servo sector from the data sector 21. The servo information 22a consists of a leading edge portion 22c extending in the radial direction of the magnetic disk 10 and a trailing edge portion 22d having a corrugated pattern which comes in and out for each track center and repeats this every two track pitches. Each servo information 22a consists of three equidistant 10 μm gap patterns extending in the radial direction. The servo separator 22b consists of two equidistant 5 μm wide patterns extending in the radial direction and analogous to the index line 23. When the radius R of the innermost recording track 20 of the recording zone 24 of the magnetic disk 20 to the center line is 38 mm, the total circumference of the inner track containing seventeen sets of data sectors, servo sectors 22 and index lines 23 is 239 mm, and 1% of 239 mm/17=14 mm, that is, 0.14 mm is preferred.
FIG. 3, as the circumferential width of each set of one servo sector 22 and one index line 23, is a cross sectional view of the recording zone 24 in the radial direction. In the drawing, an under layer 11a consisting of a 0.5 μm-thick Cr film is disposed on a disk substrate 11 made of Al, and Co-Ni magnetic films (0.05 μm thick and 7 μm wide) 12 constituting the recording tracks (track pitch T=10 μm) and the track separators (0.1 μm thick and 3 μm wide) 20a are alternately formed [TPI (Track/inch)=2,500] on the surface of the under layer 11a. Furthermore, a protective film 13 consisting of a 0.03 μm-thick carbon is formed on the top of the above mentioned assembly. The track separator 20a projects 0.05 μm from the magnetic film portion 12. The pattern portions of the servo information 22a and index line 23 in FIG. 2 are all formed in the same way as the track separators 20a and each projects by a predetermined distance (e.g. 0.05 μm) from the surface of the magnetic layer 12.
The notch 31 shown in FIG. 2 is cut 1 mm deep into the inner diameter portion 30 of the magnetic disk 10 and is formed in such a manner that the leading edge 31a of the notch 31 exists on the extension (represented by one dot-chain line in FIG. 2) of the leading edge 23a of the last index line 23 in the clockwise direction among the patterns of the index line 23, and thus the notch and index line 23 have a predetermined value of relative positional relation.
The bottom 31b of the notch 31 is spaced a predetermined distance X of 17 mm from the innermost corrugation 21c of the servo information 22a of the servo sector 22. As shown in FIGS. 1 and 5, the notch 32 is cut into the inner diameter portion 30 at the position 90° clockwise from the notch 31, and the bottom portion 32b of notch 32 is spaced the distance X of 17 mm from the center position (circumferential dot-dash line in FIG. 2 at radius R) of the information track 20 corresponding to the innermost corrugation 21c. The notches 33 and 34 are formed on the inner diameter portions 30 on the diameter lines spaced apart by 180° from the notches 31 and 32, respectively. The depth of these notches 33, 34 from the inner diameter portion 30 to the bottom in the radial direction is greater than the depth of the notch 31 (e.g. 1 mm).
The width of the notches 32, 33 and 34 in the tangential direction is greater than that of the notch 31.
The opposite surface of each magnetic disk 10 is symmetric with the just described disk surface with respect to a neutral center plane that is in parallel with the disk surface.
Next, an embodiment of the production method of the information recording disk in accordance with the present invention will be explained. FIG. 4 shows an example of the production steps of the magnetic disk in accordance with the method of the present invention.
At step (1), rough machining of a press-punched aluminum blank is conducted so that surface coarseness, plate thickness and inner and outer dimensions are finished to be greater than finish dimensions for the thus formed substrate.
At step (2), the narrow notch 31 and the wide notches 32, 33 and 34 are cut into the inner diameter portion 30 of the substrate. The width of each of the notches 32, 33 and 34 is greater by 0.5 mm than that of the notch 31. The notches 33 and 34 are cut to be 0.5 mm deeper than the notches 31 and 32 so that the radial distance (bottom to bottom) D 1 between the notches 31 and 33 and between the notches 32 and 34 is D 1 =D-(2X)+0.5 mm, where D is the diameter of the innermost track, e.g., D=38 mm×2=76, and X is defined in FIG. 2, e.g., X=17 mm.
Next, at step (3), the bottom 31b of the notch 31 and the bottom 32b of the notch 32 are fixed to the projection of a lathe corresponding to a radius of rotation R 1 (=R - X) which is smaller by X (17 mm) than the radius R (38 mm;=D (76 mm)/2) to the center line of the innermost track. Then the inner and outer diameters are machined and their corners are chamfered.
The machining method of the inner and outer diameters and the formation method of the notches are not limited to the methods described above. It is possible, for example, to machine the inner and outer diameters first and then to machine highly accurately the notches by use of a jig borer, for example. In this case, a tool having a diameter of at least 2 mm is preferably used as the tool of the jig borer in order to improve machining accuracy.
At step (4), the bottom 31b of the notch 31 and the bottom 32b of the notch 32 are positioned on a projection of a precision diamond lathe and fixed by a vacuum chuck. The projection of the lathe is retreated and the surface is smoothed by diamond turning the first substrate in the same way as machining of the inner and outer diameters of the disk substrate. After one of the surfaces of the disk substrate is turned in this manner, the notches 31 and 32 are similarly positioned to the projection of the lathe to position the other surface of the disc substrate to be smoothed and turned after retreating the projection of the lathe. In this manner, both surfaces of the disk substrate are smoothed. Any oil or the like adhering to the substrate is cleaned and washed off in step (5).
At step (6), a base plating film consisting of Ni--P alloy is formed on both surfaces of the disk substrate by electrolysis plating.
At step (7), the Ni--P plating film on both surfaces of the disk substrate is smoothly polished.
At step (8), an alumina (Al 2 O 3 ) film is formed in a thickness of 0.15 μm on the Ni--P plating film on both surfaces of the disk substrate.
Subsequently, a photoresist film is formed at step (9) by spin coating on the A1 2 0 3 film on both surfaces of the disk.
This photoresist film is exposed to the patterns shown in FIGS. 1 ˜3 at step (10) to form the resist patterns. At this time the disk substrate is held by support rods thinner than the disk at three points on the outer diameter of the disk substrate. Photomasks having set patterns are positioned to both surfaces of the disk substrate by the use of the leading edge portion 31a of the notch 31, the bottom portion 31b of the notch 31 and the bottom portion 32b of the notch 32 as the positioning references. After air between the two photomasks is evacuated, the photomasks are brought into close contact with the photoresist. Then, exposure is carried out by irradiating light to both surfaces. The diameter of the innermost recording track of the photomask is D (e.g. 76 mm) and the distance from it to the bottom portion 31b of the notch 31 and to the bottom portion 32b of the notch 32 is X (e.g. 17 mm).
Here, contact exposure is used, but as an alternative the set pattern can be exposed by projection exposure. At this time the disk substrate is positioned for each surface by pushing the three points, that is, the leading edge portion 31a of the notch 31 of the disk substrate, the bottom portion 31b of the notch 31 and the bottom portion 32b of the notch 32, to the reference pins of the exposure apparatus and the exposure pattern position is positioned to the reference mark of the exposure apparatus whose relative position with the reference pins is in advance clarified, by use of the alignment mark on the mask. After exposure of one surface, the other surface is exposed in the same way by use of the corresponding photomask.
The photoresist film exposed in the manner described above is developed at step (11) and the photoresist film at portions other than the set positions is removed. The alumina film at portions where the photoresist film does not remain is removed by plasma etching at step (11) to form a set alumina film pattern. At this time the photoresist film remaining on the alumina film is not removed.
Next, at step (12), a magnetic layer consisting of a thin metal film is formed in a thickness of 0.1 μm by sputter deposition on the surface of the disk. At this time the magnetic layer is formed on the Ni--P plating film from which the alumina film was removed by step 11 and on the photoresist film remaining on the alumina film after step 11.
At step (13), the photoresist film is removed by use of an organic solvent. At this time the magnetic layer formed on the photoresist film is removed together with the photoresist film and the alumina film is exposed. In this manner the patterns of the alumina film and magnetic layer are formed on the surfaces of the disk substrate.
At next step (14), a thin carbon film as a protective layer is formed in a thickness of 0.04 μm by sputter deposition on the entire surface of the alumina film and magnetic layer.
At final step (15), a small amount of a liquid lubricant is coated on the surface of the protective film to complete the magnetic disk of the present invention.
The steps 6 to 15 are basically well known as conventional for a thin film sputtered disk. The steps 8 to 14 are basically the production steps disclosed in Japanese Patent Laid-Open No. 0026/1986. The present invention differs from the basics of these steps in the step (10) for positioning the patterns formed on the surface of the magnetic disk to the notches 31 and 32 formed on the inner diameter portion 30 of the magnetic disk substrate 11. This step needs the formation step (2) of the notches and step (3) can insure concentricity of the inner and outer diameters of the magnetic disk by utilizing these notches. Furthermore, step (4) can limit the eccentric distance between the center of machining of the machining work and the recording tracks 20 to a low level.
Next, an example of the magnetic disk using the present invention will be explained.
The basic construction of the magnetic disk in this embodiment uses as a whole a substantially conventional apparatus but has its characterizing feature in the mechanism which fixes the magnetic disks to a rotatable hub.
FIG. 5 shows the magnetic disk as viewed from above the spindle 51. The hub 50 is fixed to the spindle 51. The diameter of the outer diameter portion 40 of the hub 50 is smaller by about 5 mm than the diameter (e.g. 40 mm) of the inner diameter portion 30 of the magnetic disk 10. The magnetic disk 10 comes into contact with the hub 50 only at the three points, that is, the leading edge portion 31a of the notch 31 in the inner diameter portion 30, the bottom portion 31b of the notch 31 and the bottom portion 32b of the notch 32, and thereby its horizontal position in the plane of FIG. 5 that is perpendicular to the spindle 51 is limited. Four projections 41, 42, 43 and 44 are formed on the outer diameter portion 40 of the hub 50 at positions 90° from each other. The outer diameter portion of each of these four projections is machined to define a radius of rotation R 1 when the spindle 51 is fixed to a bearing. This value can be known easily by measuring the gap of the outer diameter portions between the projections 41 and 43 or between the projections 42 and 44 that exist on the same diameter. As a result, high precision machining of R 1 can be guaranteed. The notch 31 is combined with the projection 41. The leading edge portion 41a of the projection 41 contacts the leading edge portion 31a of the notch 31 along surfaces that are highly precision-machined in parallel with the spindle 51.
The other projections 42, 43 and 44 are combined with the notches 32, 33 and 34, respectively. Since the width and depth of the notches 33 and 34 are greater than those of the notches 31 and 32, they do not come into contact with the projections 43 and 44 so that the horizontal position of the magnetic disk 10 can be restricted by the projections 41 and 42. A leaf spring 52 is interposed between the projections 43 and 44 and generates a force that biases the notches 31 and 32 toward the hub projection 41 and projection 42, to prevent the deviation of the magnetic disk 10 in the horizontal direction at the time of rotational acceleration or deceleration of the spindle 51, and to establish reliable contact with the three points described above.
The width of the notch 32 is greater by 0.5 mm than that of the notch 31. Therefore, when the leading edge portion 31a of the notch 31 is brought into contact with the leading edge portion 41a of the projection 41, the notch 32 contacts only at its bottom portion with the projection 42, and therefore the notch 32 and projection 42 do not interfere with the contacting between edge portions 31a and 41a.
Since the magnetic disk 10 is fixed to the hub 50 as described above, the bottom portions of the notches 31 and 32 are fixed onto the radius R 1 from the center of rotation. Since the innermost recording track is spaced by the distance X from the bottom portions of the notches 31 and 32, it is fixed at the distance of R 1 +X=R from the center of rotation. Since each recording track 20 inside the recording zone 24 on the magnetic disk 10 is formed equidistantly, the centers of all the tracks are in agreement with the center of rotation. This also holds true exactly of the plurality of magnetic disks 10 stacked on the same hub 50, and in this manner, the recording tracks on these magnetic disks 10 can be assembled with all their centers in agreement with the center of rotation.
As to the angular position of the index lines 23 inside the plane of the magnetic disk 10, since the leading edge portion 31a of the notch 31 on the extension of the index line is brought into contact with and biased to the leading edge portion 41a of the projection 41 formed in parallel with the spindle, the plurality of magnetic disks stacked on the same hub 50 can all be set to the same angular position.
Since the notches 31 and 32 are positioned by the projections 41 and 42 as described above, respectively, these plurality of magnetic disks 10 are stacked on the hub 50 while inserting therebetween spacers having a predetermined size in order to keep the gaps between adjacent disks constant, and the stacked disks and spacers are fixed by a fixing screw from above through a hub cover. The magnetic head is floated by rotating the magnetic disk assembly. The alumina pattern inclusive of the track separators 20a project by 0.05 μm above the top surface of the magnetic layer 12, but this does not hinder floating of the magnetic head if the minimum value of the floating spacing is above this 0.05 μm value.
Under this state, the position of the servo information 22a of each servo sector on the magnetic disk 10 must be detected. Therefore, a predetermined current is caused to flow through each magnetic head in the same direction so as to magnetize the adjacent magnetic layer in the same direction. This operation is repeated with a value not exceeding the minimum track width of each magnetic head, and changing the radial position so that the magnetic layers of entire recording zones 24 are magnetized in the same direction. Since each magnetic layer is discontinuous in each servo sector 22 and index line 23, the output corresponding to each pattern position of the magnetic layer can be detected by the magnetic head. In other words, since the patterns of the servo information 22a are continuous lines in the radial direction at the leading portion 22c throughout all the recording tracks, a predetermined start of the signal output is produced at all the radial positions, but since the patterns come in and out alternately on the center line of each track at the trailing portion 22d, the shapes of the signal outputs are different depending on the radial positions. The peak values or shapes of these two outputs are determined by the time positions of the trailing portion 22d and they become equal to each other when the magnetic head reaches the center line of each track. Therefore, the difference of the peak values of the two pulse outputs having different time positions from the trailing portion 22d of the pattern of each servo information 22a is generated by a position information circuit and the positioning mechanism is driven so that this value becomes zero. In this manner, the magnetic head can be positioned to the center line of each information track. The output signal reproduced in this case is the same as the so-called "tri-bit" pattern that has been obtained by conventional magnetic write/read and its basic operation can be easily understood by those skilled in the art.
On the other hand, at the portion of the data sector 21, the magnetic film pattern is only the track separators 20a and all of them are formed in the circumferential direction and do not have magnetic discontinuous points. Accordingly, leakage flux does not occur and the magnetic head reproduces only the data signal.
In the magnetic disk recording apparatus of this embodiment, the radial position on the positioning mechanism of one magnetic head is assembled so that it is in high precision conformity with others. In other words, the plurality of magnetic heads on one head support mechanism are aligned and fixed highly accurately at their radial positions with one another at the time of assembly of the magnetic head and when they are fixed to the magnetic head positioning mechanism, they are fixed after their radial positions are adjusted in the same way as has been made in the conventional disk pack exchange type magnetic disk recording apparatuses.
The re-positioning time of the switching from one to another of the magnetic heads can be shortened by forming the two positioning notches on the inner diameter portion and bringing the positioning pattern on the magnetic disk into conformity with the rotation driving center of the magnetic disk recording apparatus. However, the present invention is not particularly limited to this structure. For example in FIG. 6, the magnetic disk 10 can be positioned to the hub 66 of the recording apparatus by aligning the horizontal position with three notches 61, 62 and 63, in the disk 10 and by one each straight line surfaces 60 , 68, 67 and a projection having contact portion 64 as shown in FIG. 6. Leaf spring 65 biases the contact portion at the terminal end of the projection radially against the adjacent bottom surface of notch 63, biases surface 68 against the adjacent surface of notch 62 and biases surface 60 against the adjacent surface of notch 61.
As shown in FIG. 7, it is possible to form only one notch 70 in the inner diameter of the magnetic disk 10, to align the rotation angle position of the magnetic disk by this notch 70 and to align the radial position by two projections 71 and 72 formed on the hub 74.
Furthermore, it is possible to fix positioning keys 81 and 84 rigidly on the outer diameter portion of the hub 86 and to make positioning at three points by biasing with a spring urged piston 87 and spring 88, that is, the side surfaces 82, 83 of key 81 contact the surface notch 80 of the magnetic disk, 10 and the outer diameter surface of the other key 84 contacts the inner diameter 85 of disc 10, as shown in FIGS. 8(a) and 8(b).
It is further possible to use a positioning mark disposed in advance on the surface of the magnetic disk, not shown, in place of the notch on the inner diameter portion as the positioning reference, to detect optically the positioning mark of the magnetic disk when the disk is fixed to the hub of the magnetic disk recording apparatus and to position the inside surface of the magnetic disk to the center of rotation. In these cases described above, positioning at the time of production of the magnetic disk uses fully the positioning reference in accordance with the method described above.
Though this embodiment has been described with reference to the pattern shown in FIG. 2, the patterns of the magnetic layer/alumina film are not particularly limited thereto and a grid-like pattern which switches at the center of each track center may be used for the servo information as shown in FIG. 9. These patterns repeat every second track, and the magnetic head might be positioned to tracks other than the desired track at the time of switch of the magnetic heads if the eccentric distance between the center of the recording track 20 and the center of rotation of the hub 50 exceeds the width of one track. However, the arrangement wherein the repeating length of the servo information pattern exceeds the two tracks is well known to those skilled in the art. It is possible, for example, to use three or more kinds of gaps between the leading edge portion and trailing edge portion of the servo information 22a in place of the two kinds shown in FIG. 2. In these cases, the magnetic head, even when it is switched, can be positioned to the desired track if the eccentric distance between the center of the recording track 20 and the center of rotation of the hub 50 is below 1/2 of the repeating unit.
FIG. 10 shows a magnetic disk storage that utilizes the present invention. Six magnetic recording disks 10, each having magnetic recording tracks 20, are made by the above described method using a pattern of a change in shape or materials. They are stacked on the hub 50 while inserting spacers having a predetermined size between the disks in order to keep their gaps constant, and they are fixed by a fixing screw 54 from above through a hub cover 53.
Hub 50 is supported on journal bearing 130 and rotated by the drive motor 120 in the housing 100. Magnetic tracks shown in FIGS. 1,2, or 9 are fabricated on the recording surfaces of magnetic disks 10. The disks are fixed on the hub within small errors of eccentricity as previously explained. Information is recorded and/or reproduced on the magnetic tracks by magnetic heads 90.
Twelve magnetic heads 90 are placed on both sides of the six magnetic recording disks. They are supported by leaf springs 91 and are mounted on the support arm 92. All the magnetic heads 90 are fixed on the carriage 200 simultaneously. The magnetic heads are positioned to a desired recording track by the accessing of carriage 200 which moves to the radial direction of the magnetic recording disks by the actuating mechanism 110.
The recording and/or reproducing position of the twelve magnetic recording heads are aligned to make the error of eccentricity of all the disks within 1 micrometer at the time of fixing the magnetic heads on the carriage.
The apparatus are equipped within the housing 100 and dust particles from outside the housing are kept out through the filter unit 105 and the inside air pressure is kept the same as that of the outside.
Though the description given above deals with the case where the present invention is applied to the magnetic disk and to the magnetic disk recording apparatus, the information recording method is not particularly limited thereto, and exactly the same effect can of course be obtained when an optical recording system is employed.
In accordance with the present invention described above in detail, the information recording disk having the recording tracks formed on its information recording surface can be fixed to the spindle with a small eccentric distance between the center of the recording track and the center of rotation of the information recording disk. Accordingly, the following error of the access mechanism can be reduced. Even when a plurality of information recording disks are fixed to the same spindle, the centers of the recording tracks on all the disks can be accurately brought into conformity with one another. Therefore, when at least two recording/reproduction mechanisms corresponding to these information recording disks are mounted to one driving mechanism and positioning in the radial direction is carried out, the positioning time can be reduced remarkably even when the recording/reproduction mechanism is switched from one to the other. Furthermore, when recording/reproduction of one track is complete and shifts to the recording track of the next information recording disk surface, the waiting time until the start of the recording/reproduction start position of that disk surface can be shortened.
In accordance with the present invention, the position reference signal pattern on each recording track is formed at the time of production of the information recording disk. Therefore, it is not necessary to form the position reference signal after the assembly of the recording apparatus and the assembly step of the recording apparatus can be simplified.
In the magnetic disk structure of the present invention, the alumina film projects from the magnetic layer and prevents the contact of the head with the magnetic layer. Accordingly, it is possible to remarkably reduce the probability that the information recorded on the magnetic layer cannot be reproduced due to sliding contact with the magnetic head. Since the patterns of track separators and servo sectors are simultaneously formed, alignment accuracy of the recording track center with the servo information can be improved more highly than when only the track separator portion is formed on the magnetic disk surface and the servo information is recorded after the assembly of the recording apparatus.
In accordance with the present invention, machining of the inner and outer diameters of the information recording disk can be made by utilizing the same positioning information as that used for the recording track and the eccentric distance between the inner and outer diameters can be reduced when the disks are assembled to the recording apparatus and the rotating vibration of the recording apparatus during the high speed rotation can be reduced. Furthermore, the recordable range of each information recording surface can be expanded.
In the present invention, each information recording disk is biased to the hub and its position in the surface direction is aligned, and the movement of the disk, even when acceleration is applied thereto at the start/end of rotation, can be prevented. Accordingly, the fixing force for fixing the disk to the hub can be reduced, deformation of the hub and disk due to the fixing force can be reduced and planar accuracy can be improved. Moreover, since deformation of the hub can be reduced, strength of the hub can be reduced and the constituent components can be made light in weight and compact in size.
In accordance with the present invention, furthermore, an extremely easy-to-use and highly reliable information recording apparatus can be accomplished because it uses the information recording disk(s) which has the recording tracks formed in advance on its information recording surface(s) and makes it possible to make high precision positioning.
While a preferred embodiment has been set forth along with modifications and variations to show specific advantageous details of the present invention, further embodiments, modifications and variations are contemplated within the broader aspects of the present invention, all as set forth by the spirit and scope of the following claims. | In the information recording disk, the positioning signal of the information convertor is provided permanently, as a change in shape or material, to the front and reverse surfaces of the disk substrate and their eccentric distances from the center position is made to be smaller than half the repeating unit length of the positioning signal of the information convertor in the radial direction. The start position of the positioning signal in the circumferential direction is preferably made to be coincident on the front and reverse surfaces of the disk substrate within 10 μm. The position reference for aligning the position in the radial direction or the position reference for aligning the rotation angle position in the circumferential direction is preferably disposed on the inner diameter portion or outer diameter portion of the disk substrate, respectively, and these position references can be accomplished by disposing at least one notch on the inner or outer peripheral edge portion of the disk substrate. | 6 |
BACKGROUND OF THE INVENTION
The invention is based on a fuel injection pump as defined hereinafter.
Before fuel injection pumps of this kind, embodied as multi-cylinder pumps having a series of pump elements, are put into operation, an exact association of the individual control slides with respect to the various control openings must be made, since during pump operation the individual control slides are displaced simultaneously and in common by the rotary shaft, for variation of the instant of injection or the injection quantity. Even slight errors in this association, that is, differences in the desired control points of the various control slides with respect to one another, can lead to considerable errors in the control of injection onset or injection quantity, which in turn can for instance lead to rough engine operation or excessively noisy combustion.
These deviations in the association of the individual control slides with respect to one another are due to tolerances originating in the machining or assembly process, or in the pump drive shaft, and the deviations can be superimposed on one another. These deviations must be eliminated, by positioning the control slides uniformly with respect to the control openings before the pump is put into operation.
In a known fuel injection pump of this generic type (German Offenlegungsschrift 35 22 414), the driver tang is secured to a clamping ring encompassing the rotary shaft; once the clamping ring is loosened, the position of the tang, and thus the axial position of the control slide relative to the rotational position of the rotary shaft, can be varied. Not only does the adjusted position between the driver arm and rotary shaft shift on its own, given the heavy loads and constant jarring that a fuel injection pump undergoes, but adjustment is also a relatively labor-intensive operation because it requires making a direct comparison between the various pump elements; moreover, when the clamping rings are adjusted on the rotary shaft, they may exert torque upon the shaft that can lead to further errors in adjustment A further disadvantage is that the adjustment can be done only in the installed condition; only then can the individual association between the change in rotational position of the rotary shaft and the clamping ring, on the one hand, and the change in axial position of the control slide, on the other, be reliably performed, which has the disadvantage that for adjustment, an intervention into the suction chamber must be made when it is at feed pump pressure.
In another known fuel injection pump of this generic type (German Offenlegungsschrift 35 40 052), the driver arm is disposed eccentrically on a spindle that penetrates the rotary shaft radially and is clamped to it with a tightening nut. When the spindle is rotated, which is done by engaging a slit with a screwdriver after the tightening nut is loosened, the driver arm is adjusted as a function of its eccentricity with respect to the axial position of the control slide. In this known apparatus as well, the fact that the adjustment, once made, loosens on its own again is all the more disadvantageous, the smaller the friction faces involved in the tightening of the spindle. Also, once again this adjustment can be performed only with the rotary shaft in its installed state, and once again the suction chamber, which is under pressure, must be opened up.
In yet another known fuel injection pump of this generic type (European patent application 0181 402), a fork-like device having a gripper insert acts as the driver element; it is connected to the rotary shaft either with a tubular clamp, in which case the rotary shaft is round in cross section, or via a bolt, disposed on the face end of the forked lever facing the rotary shaft, which in that case has a polygonal cross section. Although in the first case adjustment is relatively simply done by rotating the "tubular clamp" on the rotary shaft, there is still the danger that jarring in such systems easily loosens the clamp tension and can cause the control slide association to change, possibly in the direction of increasing fuel quantity, which will cause the engine to race. The second case is extremely unfavorable in terms of force transmission, because the area of contact, between the lever and the rotary shaft, that is operative in the longitudinal direction of the lever is relatively narrow, and moreover, as noted above, the desired adjustability is not available.
OBJECT AND SUMMARY OF THE INVENTION
The fuel injection pump according to the invention has the advantage over the prior art that a very accurate adjustment is attained by means of a permanent deformation, which does not change from jarring or loads during operation and is extremely favorably attained. This deformation is performed with the rotary shaft in the disassembled state, after the axial deviations have been measured with the rotary shaft in the assembled state. The forces required for the plastic deformation are must greater than those for actuating the control slides, which precludes material deformation during operation. Above all, the fastening element can have a non-releasable connection with the rotary shaft.
In an advantageous feature of the invention, a bolt that penetrates the rotary shaft and can be riveted or screwed to it is used as the fastening element. For the adjustment according to the invention, the driver arm can advantageously be rigidly joined to the rotary shaft, for instance with rivets. Naturally the connection can also be effected by hard soldering or welding, but that has the disadvantage of involving an additional heat treatment.
In a further advantageous feature of the invention, a flattened face or recess is provided on the rotary shaft in the vicinity of the bolt, and there is at least one protrusion limiting the flattened face or recess on at least one side, and a complementary feature is provided on the bolt, serving to secure the bolt against relative rotation. For example, if the rotary shaft has a circular cross section, then the flattening can be obtained by removing material transversely to the axis of the rotary shaft; the segmental surface then formed between the remaining cylindrical surface and flattened face acts as a stop against rotation, to which end, however, the fastening element on which the driver arm is disposed is profiled accordingly, for instance having a square profile. With a rotary shaft of profiled cross section, for instance a rectangular or square cross section, the profiled faces can serve as a flattened face; if they are suitably embodied, for instance as longitudinal recesses, and if the fastening element is profiled for cooperation with them, then a means of fixation against relative rotation is attained.
In a major feature of the invention, the driver arm is tapered toward the free end, and the longitudinal cross section is preferably paraboloid, so that a uniform bending tension is exerted on the arm length when the driver arm is deformed. With this kind of third-order paraboloid, the force during the cold deformation is introduced at the apex, resulting in a uniform deformation over the entire bending range, that is, over the bendable length of the driver arm. The result, above all, is that fissures and hence permanent damage to the driver arm are not produced (see DubbelTaschenbuch fur den Maschinenbau [Dubbel's Handbook of Mechanical Engineering], Volume 1, 1955, pages 131 and 346). In the vicinity of the bendable arm length, instead of being embodied as a paraboloid the driver arm can be embodied approximately as a cone, which is particularly easy, because the free end of the driver arm becomes a reinforced, cylindrical tang.
In another advantageous feature of the invention, the fastening element is a sleeve, encompassing the rotary shaft and having a thin, deformable section disposed between two reinforced collars at its ends. One collar is fastened to the rotary shaft in a manner fixed against relative rotation, while the other collar is merely supported on the shaft and carries the driver arm. Naturally, this embodiment is possible only with a round rotary shaft, to enable the corresponding relative rotation of the second collar. To facilitate the plastic deformation, slits or bores may be provided in the deformable section.
In a further feature of the invention, which is equally applicable to the above-mentioned features, the free end of the driver arm has a cylindrical tang, on which a slide block that engages a transverse groove in the control slide is supported with a central bore; the slide block is secured against axial displacement on the tang. This advantageously makes for a line contact between the slide block and the control slide groove, which reduces wear.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical cross section through a fuel injection pump according to the invention;
FIG. 2 is a perspective view showing two variants of the first exemplary embodiment;
FIG. 3 is a section taken along the line II of FIG. 2;
FIG. 4 is a corresponding section taken through a third variant of the second exemplary embodiment; and
FIG. 5 is a perspective view of the second exemplary embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The fuel injection pump shown in FIG. 1 is equally applicable for both exemplary embodiments of the invention. In this pump, a plurality of cylinder liners 2 are disposed in line in a housing 1, only one of them being visible because of where the section is taken. In each of the cylinder liners 2, one pump piston 3 is driven for its axial motion forming the working stroke by a camshaft 6, via an interposed roller tappet 4 having a roller 5, counter to the pump feed pressure and counter to the force of a spring 7. Recesses in the cylinder liners 2 and hollow spaces in the housing 1 defined a suction chamber 8, for the pump elements embodied by the cylinder liners 2 and pump pistons 3. One control slide 9 is axially displaceably disposed on each of the pump pistons 3, in the recesses of the cylinder liners 2. The suction chamber 8 is closed at its longitudinal ends by bearing plates 11, one of which is shown in plan view, and in which a rotary shaft 12 disposed in the suction chamber 8 is supported. A transverse groove 13 in the control slide is engaged by a driver tang 14 of a driver arm 15 of the rotary shaft 12, the tang being joined to the rotary shaft with a fastening element 16.
The pump piston 3, the cylinder liner 2 and a pressure valve 17 define a pump work chamber 18, from which a pressure conduit 19 leads to a pressure line, not shown, that ends at an injection valve of the engine. Provided in the pump piston 3 are a blind bore 22, which terminates at the face end of the pump piston and discharges into the pump work chamber 18, and a tranverse bore 23, which discharges into oblique grooves 24; one oblique groove 24 each is disposed on opposite sides of the jacket face of the pump piston 3. These oblique grooves 24 terminate at the bottom in countersunk bores 21 and cooperate with radial bores 25 of the control slide 9.
To secure the control slide 9 against rotation as it is axially displaced on the pump piston 3, and to assure precise association of the oblique grooves 24 with respect to the radial bores 25, the control slide 9 has a protrusion 26, with which it engages a longitudinal groove 27 of the cylinder liner 2.
The pump piston 3 has flattened faces 28 on its lower end, which are engaged by a bushing 31 that is rotatable in a known manner by a governor rod 29, so that an axial displacement of the governor rod 29 causes a rotation of the pump piston 3 and hence a change in the association of the oblique grooves 24 relative to the radial bores 25.
A suction bore 32 extends in the cylinder liner 2 and in the pump housing 1, betwen the suction chamber 8 and the pump work chamber 18; this bore 32 is opened by the pump piston 3 when it is at bottom dead center (as shown in the drawing).
The supply of fuel to the suction chamber 8 is effected via the longitudinal groove 27 from an inflow conduit 33, which extends in a tube 34 that is disposed in the housing 1 and has branch openings 35 toward the longitudinal grooves 27.
OPERATION
This fuel injection pump functions as follows:
Toward the end of the intake stroke, or at the bottom dead center position of the pump piston 3, fuel flows via the oblique grooves 24, the transverse bore 23 and the blind bore 22 as well as the suction bore 32 into the work chamber 18 and fills it. Then as soon as the roller tappet 4 is displaced upward via the roller 5, in the course of further rotation of the camshaft 6, the pump piston 3 positively displaces fuel from the pump work chamber 18. Until the oblique grooves 24 and the countersunk bores 21 have become entirely immersed in the control slide 9, pumping takes place from the pump work chamber via the above-described route, back to the suction chamber 8; initially, a certain quantity is still positively displaced back via the suction bore 32. As long as the oblique grooves with the countersunk bores 21 are completely immersed in the control slide 9, an injection pressure can build up in the pump work chamber 18; after that, the pumping of fuel to the engine takes place via the pressure conduit 19. This actual injection stroke of the pump piston 3 is interrupted whenever the oblique grooves 24 coincide with the radial bores 25, causing the fuel to be pumped back into the suction chamber 8 from the pump work chamber 18.
Depending on the rotational position of the pump piston 3, which is determined by the governor rod 29, this actual injection stroke is of variable length, because as a function of this rotational position, the oblique grooves 24 coincide with the radial bores 25 only after a certain length of stroke. This determines the injection quantity. The injection onset, contrarily, is determined by the axial position of the control slide 9, which in turn is determined by the rotary shaft 12, that is, by its driver arm 15 and driver tang 14. The higher the level to which the control slide is displaced, the later does the injection onset occur (which takes place when the oblique grooves 24 become immersed in the control slide 9), and correspondingly the later does the injection cease, so that the fuel quantity, which is determined by the rotational position of the pump piston 3, remains unaffected. This onset or end of injection must agree, for all the pump elements of one row.
Since dimensional deviations within a given tolerance range are unavoidable in the manufacture and assembly of a fuel injection pump, they must be corrected before the fuel injection pump is used on the engine. That is, at a particular rotational position of the rotary shaft 12, all the control slides 9 must assume specific axial positions with respect to the oblique grooves 24, so that the angular difference of the cylinders with respect to one another at the onset of pumping is always uniform. This is attained in that the position of the driver tang 14 with respect to the rotational position of the rotary shaft 12 is changed by adapting the position of the various driver tangs to one another or to the control slides 9; this is done by deforming the driver arm 15 or fastening element 16.
In the first exemplary embodiment, shown in FIGS. 2-4, this change is done by bending the driver arm 15. In FIG. 2, a portion of the rotary shaft 12 is shown, having two built-in driver arms 15, which are secured to the rotary shaft 12 via a fastening element 16 that is disposed at intervals on the rotary shaft 12. The fastening element 16 has a flange 36 which is proximate to this end, that rests on a flattened face 37 of the rotary shaft 12. The fastening itself may be rigid or releasable, for instance being in the form of a screwed, riveted or soldered connection. If a riveted connection is used, the loosening of which could allow rotation of the driver arm, then the flange 36 may have a profiled cross section, so that it is supported on at least one of the segmental faces 38 of the flattened face 37 and is prevented from rotating on its own. If the driver arm 15 were to rotate, the intentional bending that is performed might take place in the opposite direction from that desired.
In the two variants shown in FIG. 2, a separate driver is provided for transmitting the rotational motion from the driver arm 15 to each control slide 9. In the first variant, on the right in FIG. 2, the driver 39 is embodied as an annular collar, rounded in spherical segmental form on the outside, which is formed onto the driver tang 14 and is secured against falling out. In the second variant shown in FIG. 2, the driver 41 is embodied as a slide block and is secured against axial displacement and hence against falling out, by means of a locking key 42 and with a certain amount of rotational play, on the end of the driver arm 15 embodied as a driver tang.
In FIG. 3, this variant is shown in section; the dot-dash line indicates the directions in which the bending is possible, and how the position of the slide block 41 would change in each case.
In the third variant of this first exemplary embodiment, shown in FIG. 4, the rotary shaft 112 is embodied as a profiled bar of rectangular cross section, in which there is a longitudinal groove 43. This longitudinal groove has a bottom face 44 and side faces 45. The fastening element 116 is embodied as a rivet, with a flange 136 of square cross section, so that the side faces of the flange 136 cooperate with the side faces 45 of the longitudinal groove 43 in such a way that the driver arm 115 is prevented from rotating. The driver arm 115 itself is embodied conically, in the ideal case parabolically, with a cross section that tapers away from the rotary shaft. In the ideal case, that is, the parabolic case, this assures that with forces engaging the free end of the driver arm 115 in order to bend it, constant bending tensions will prevail over the entire bendable arm length, which above all prevents breakage or unilateral overloading of the driver arm 115. The slide block 41 is once again embodied as in the second variant of FIG. 2; however, the driver arm 115 is provided with a flange 46 that in combination with the locking key 42 determines the axial position of the slide block 41.
In FIG. 5, the second exemplary embodiment is shown, in which the driver arm 215 is secured on a ring 47 that is joined via a sleeve 48 to a second ring 49. Preferably the rings and the sleeve are all in one piece, the rings 47 and 49 being embodied as collars of this sleeve 48. The slide block 41, as in the second variant of FIG. 2, is fastened to the driver arm 215. The rings 47, 49 and sleeve 48 are threaded onto the rotary shaft 212, which in this case is again of circular cross section, and the ring 49 is firmly clamped via at least one screw 51. Bores 52 are also provided in the sleeve, for the sake of intentionally weakening a portion the sleeve 48. For the desired plastic deformation, the ring 47 is rotated relative to the ring 49, so that the sleeve portion 48 is rotated slightly in a helical manner, and the driver arm 215 undergoes the desired change in position relative to the rotational position of the rotary shaft 212.
Thus, it is believed to be apparent from the foregoing that one pertinent aspect of this application involves a sleeve which surrounds the rotary shaft with each end of the sleeve being rigidly secured to a respective collar. One of the collars is affixed to the rotary shaft and the other of the collars carrying a radially extending driver tang, the arrangement being such that the collars have an initial angular relationship. The driver tang is positioned in a transverse groove in a control slide. The sleeve is provided with means to permanently absorb a relative twist therein whereby upon being relatively twisted, the collars will thereafter remain in a specific relative angular relationship by virtue of the permanent absorption by the sleeve of a twist .
The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | A fuel injection pump for internal combustion engines having a plurality of pump elements disposed in a row, the onset and end of supply of each being effected by means of a respective control slide that is axially displaceable on the pump piston and by the control of relief conduits for the pump work chamber. The control slides are actuated via a rotary shaft; upon rotation of the rotary shaft, the control slides are axially displaced via driver arms secured on the rotary shaft. To adjust the axial position of the individual control slides relative to one another, the driver arms are permanently deformed in the axial direction of the control slides. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims the benefit of provisional application Ser. No. 60/816,524, filed Jun. 26, 2006, for all useful purposes, and the specification and drawings thereof are included herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to smokable products, such as cigarettes, and in particular to methods and processes that reduce the content of certain harmful or carcinogenic substances, including polycyclic aromatic hydrocarbons (PAHs), especially benzo[a]pyrene (BaP) in both mainstream smoke (MS) and side stream smoke (SS).
BACKGROUND OF THE INVENTION
[0003] Smokable products, such as cigarettes and tobacco, contain carcinogenic compounds including polycyclic aromatic hydrocarbons (PAHs). Finding approaches to reduce the levels of these carcinogenic compounds has long been a goal in this technical art.
[0004] One approach to removing undesired components from cigarettes and tobacco smoke is the use of catalysts. Palladium catalyst systems have been proposed for cigarettes. Examples of background art in this technical area include the following U.S. patents: U.S. Pat. No. 4,257,430 to Collins et al.; U.S. Pat. No. 4,248,251 to Bryant et al.; U.S. Pat. No. 4,235,251 to Bryant et al.; U.S. Pat. No. 4,216,784 to Norman et al.; U.S. Pat. No. 4,177,822 to Bryant et al.; and U.S. Pat. No. 4,055,191 to Norman et al., each of which is incorporated by reference in its entirety. These early attempts at incorporating catalytic systems into mass-produced cigarettes have met with limited success. Therefore, there is a need in the art for a catalytic system that reduces the levels of certain carcinogenic or otherwise undesirable components from tobacco smoke, and which is amenable to use in mass-produced cigarettes, is desirable.
[0005] A more recent example of background art in this technical area is U.S. Pat. No. 6,789,548 to Bereman et al., which relates to a method for making a composition for smokable materials in general and in particular to catalytic systems that reduce the content of certain harmful or carcinogenic substances. Specifically, Bereman et al. discloses palladate salts, especially ammonium salts such as ammonium tetrachloropalladate and ammonium hexachloropalladate. In fact, many other background art approaches in this art area use hexachloropalladate forms which typically require high levels of Chloride and high pH solutions. Typically, these higher pH solutions are needed in order to achieve high solubility for the palladium. However, such high pH hexachloropalladate solutions can have dramatic negative effects on equipment and/or required additional steps be added to the process.
[0006] Further, Bereman et al. discloses that, on preferred embodiments, a catalyst system including catalytic metallic and/or carbonaceous particles and a nitrate or nitrite source is incorporated into the smokable materials so as to reduce the concentration of certain undesirable components in the resulting smoke (e.g., PAHs). Other background art approaches also require the use of nitrate to achieve their required reductions in PAHs.
[0007] Furthermore, Bereman discloses in embodiments wherein the particles are metallic; the particles are preferably prepared by heating an aqueous solution of a metal ion source and a reducing agent. Other previous patents have required the heating be between 50 and 90 degrees C. in order to aid in converting most of the soluble palladium to insoluble palladium. The additional requirements of adding nitrate/nitrite and heating, as discussed above, are examples of steps that are added to the process for treating smokable materials in the background art.
[0008] Therefore, there is a need in the art for an apparatus and method for application of palladium salts to smokable materials without the detrimental effects of high pH and additional preparation or processing steps often required with background art concentrations of hexachloropalladate. In addition, there is a need in the art for a method where no nitrate materials are required in order to achieve the necessary PAH reductions. Further, there is a need in the art for a palladium salt solution that can be applied without any additional heat requirements in order to convert soluble palladium into insoluble palladium. Furthermore, there is a need in the art for a Pd Salt solution that does not need to be mixed with other solvents or casings to achieve the desired affects. That is, so the normal tobacco casings and flavors can be processed separately and so that no catalytic effects are created due to these components.
SUMMARY OF THE INVENTION
[0009] The present invention provides improvements to apparatus and methods for the process of applying palladium salts to tobacco cut filler so that polycyclic aromatic hydrocarbons (PAHs) can be reduced in both mainstream (MS) and sidestream (SS) cigarette smoke. The reduction in PAHs is observed in the total particulate matter (TPM) of the mainstream (MS) and sidestream (SS) smoke. Additionally, substantial reductions in heavy metals and Ames biological activity can be achieved when the palladium salt solution is applied and processed in accordance with the present invention. The present invention provides these improvements by using a preferred ratio of palladium (Pd) salt to Chloride (Cl) that is specifically designed to allow for high palladium solubility. Further, the present invention provides an apparatus and method for applying the palladium salt solution while minimizing the number of processing steps required. Moreover, the present invention avoids any potential increase in Nitric Oxide (NO) in smoke since nitrate is not used.
[0010] One embodiment of the present invention is an apparatus for applying a Pd salt solution comprising: a cutter unit; a feeder unit; a Pd Salt Solution Preparation Unit; a Pd Application Cylinder; a dryer; and a Final Flavoring cylinder, wherein the cutter unit receives and prepares tobacco cut filler; the feeder unit receives and feeds the tobacco cut filler from the cutter unit to the Pd Salt Solution Application Cylinder, the Pd Salt Solution Application Cylinder receives and sprays the tobacco cut filler with a metered Pd Salt solution from the Pd Salt Solution Preparation unit, the dryer unit receives and dries sprayed tobacco cut filler from the Pd Application Cylinder, and the Final Flavoring Cylinder receives dried tobacco cut filler from the dryer unit.
[0011] Preferably the Pd Application Cylinder is a rotating cylinder that allows tobacco cut filler to enter with some residence time such that a set of spray nozzles can apply Pd Solution to the tobacco cut filler. Further, preferably the Final Flavoring Cylinder is a rotating cylinder that allows tobacco cut filler to enter with some residence time such that a set of spray nozzles can apply final flavoring to the tobacco cut filler.
[0012] In addition, a preferred embodiment of the Pd Salt Solution Preparation unit further comprises a Pd Salt Solution Source, a Pd Concentration Metering Unit; a Pd De-ionized Water Source; a De-ionized Water Metering Unit; a Pd Salt Solution Tank; and a Pd Salt Solution metering unit, wherein the Pd Concentration Metering Unit and the De-ionized Water Metering Unit are configured to provide metered amounts of the Pd Salt Solution Source and the De-ionized Water Source, respectively, as inputs to the Pd Solution Tank, and the Pd Salt solution Metering Unit is configured to provide the metered Pd Salt solution to the Pd Application Cylinder.
[0013] Preferably the Pd Concentration Metering Unit is a volumetric feeding system that is based on a ratio of De-ionized water-to-Pd Solution. Further, the De-ionized Water Metering Unit is preferably a volumetric flowmeter that ensures the proper ratio of de-ionized water-to-Pd Solution. A non-limiting example of such a unit is a turbine flowmeter. Preferably, the Pd Solution Tank is made of plastic or other similar materials (e.g., metals such as Hastelloy ‘C’) and includes means for agitating. Non-limiting example of plastic would be polypropylene and means for agitating would include but are not limited to a mixer, stirrer and other well known means for mixing/agitating a solution. Preferably the Pd Salt Solution metering unit is a mass flow meter that applies the correct amount of Pd Solution depending on flowrate of tobacco cut filler entering the Pd Application Cylinder.
[0014] Another embodiment of the present invention is a method for applying the palladium salt solution comprising: preparing tobacco cut filler; feeding the tobacco cut filler to a Pd Application Cylinder; metering an amount of Pd Salt solution from a Pd Salt Solution tank; spraying the tobacco cut filler with the metered amount of Pd Salt Solution in a Pd Application Cylinder; and other, drying the sprayed tobacco cut filler in a drying unit; and processing the dried tobacco cut filler. Non-limiting examples of standard drying techniques include, but are not limited to, rotating a cylinder or drum as hot air passes through the cylinder or drum; and drive off water or other liquids from tobacco cut filler until you reach a desired degree of dryness.
[0015] Preferably, the present invention uses filler that can be wetted with the palladium solution starting with tobacco cut filler at 12% oven volatiles (OVs) up to and including 45% OV, depending on the level of palladium required in the final tobacco filler. This range of OVs gives great latitude in achieving the proper percentage of palladium in the final tobacco filler. Preferably, the concentration for palladium salts relative to tobacco weight is between 0.01% and 0.15%.
[0016] Preferably, the present invention uses palladium (Pd) in the form of tetracholorpalladate along with salts that include, but are not limited to, potassium, ammonia and sodium. In particular, examples using potassium tetrachloropalladate are presented below. The present invention maintains a proper ratio of chlorine (Cl)-to-palladium (Pd) (i.e., Cl:Pd) by maintaining a proper solution pH and achieves >99% palladium solubility. This ratio of Cl:Pd not only provides extremely high palladium solubility but also provides extended shelf life without any precipitation.
[0017] In examples given below, testing showed that extended use of tetrachloropalladate solutions caused pitting and damage to industry standard stainless steel cylinder and wetted parts. This is due to the fact that the chloride content in the solution attacks the chromium in the stainless steel. Other metals such as inconel and monel also show similar behavior. In addition, Hastelloy ‘C’ was used for all metal wetted parts.
[0018] The apparatus and method of the present invention allows the palladium salt solution to be applied without any additional solution preparation. Despite the pH of the solution (i.e., in the range of 2.5-4.5) being fairly acidic, application and processing of smoking materials with the palladium solution of the present invention: (1) does not show any increase in overall tobacco pH; (2) does not affect the level of reducing sugars; and (3) does not negatively affect previously added casings or downstream flavor addition. Moreover, the apparatus and method for applying the palladium solution of the present invention in a separate step from casing addition requires no other additional processing steps.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The invention can be described in greater detail with the aid of the following drawings.
[0020] FIG. 1 is an exemplary block diagram showing the functional blocks used to implement the apparatus of the present invention;
[0021] FIG. 2 is an exemplary flow diagram presenting the method of the present invention;
[0022] FIG. 3 is a exemplary block diagram of the testing sequences used in a Palladium Application Study;
[0023] FIG. 4 is an exemplary block diagram for the Casing Train measurement;
[0024] FIG. 5 is an exemplary block diagram for the Drying Train measurement;
[0025] FIG. 6 is test data from the Pd Level testing;
[0026] FIG. 7 is test data from the pH Level testing; and
[0027] FIG. 8 is test data from the Nitrate Nitrogen testing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] The exemplary system block diagram of FIG. 1 shows the apparatus of the present invention. In particular, FIG. 1 presents an apparatus for application comprising a cutter unit 1 ; a feeder unit 3 ; a Pd Salt Solution Preparation Unit 5 ; a Pd Application Cylinder 7 ; a dryer unit 9 ; and a Final Flavoring Cylinder 11 . As shown in FIG. 1, the cutter unit 1 receives and a cut prepared filler and is connected to the feeder unit 3 . The feeder unit 3 receives tobacco cut filler 4 from the cutter unit 1 and feeds filler 8 to the Pd Salt Solution Application Cylinder 7 . The Pd Salt Solution Application Cylinder 7 receives filler 8 from the feed unit 3 and sprays the filler 8 with a metered Pd Salt solution 12 from the Pd Salt Solution Preparation unit 5 . The dryer unit 9 receives sprayed filler 16 from the Pd Salt Solution Application Cylinder 7 and dries the sprayed filler 16 . The Final Flavoring Cylinder 11 receives the dried filler 20 from the dryer unit 9 and sprays final flavor on filler 24 and sends to processed tobacco cut filler storage.
[0029] As discussed above, the metered Pd salt solution 12 is applied to the filler 8 in the Pd Application Cylinder 7 . A metered Pd Salt solution 12 can be provided at the time of application by the Pd Application Cylinder 7 from the Pd Solution Tank(s) 17 of the Pd Salt Solution Preparation Unit 5 , as shown in FIG. 1.
[0030] Alternatively, as shown in FIG. 1, the Pd Salt Solution 12 can be made ahead of time as a concentrated Pd Salt solution 28 supplied by a concentrated Pd Salt Source 13 . The amount of concentrated Pd Salt Solution 28 is determined by a Pd Concentration Metering Unit 15 connected to the concentrated Pd Salt Source 13 . The metered concentrated Pd Salt Solution 36 is provided to the Pd Salt Solution Tank(s) 17 . The concentration of the concentrated Pd Salt Solution 36 can be diluted further to provide a predetermined concentration of Pd Salt Solution 12 with De-ionized water 32 supplied from a De-ionized Water Source 19 . The amount of De-ionized water 32 provided to the Pd Salt Solution Tank(s) 17 is metered by a De-ionized Water Metering Unit 21 . A Pd Salt Solution Metering Unit 23 provides a predetermined concentration of Pd Salt Solution 40 as the metered Pd Salt Solution 12 that is received by the Pd Application Cylinder 7 for spraying onto the tobacco cut filler 8 .
[0031] FIG. 2 is an exemplary flow diagram presenting the method of the present invention. In particular, FIG. 2 shows a method for applying a palladium salt solution where step 51 is preparing tobacco cut filler. In step 53 of FIG. 2, the tobacco cut filler is fed to a Pd Application Cylinder. Metering an amount of Pd Salt solution from a Pd Salt Solution tank occurs in step 55 of FIG. 2 and spraying the tobacco cut filler with the metered amount of Pd Salt Solution occurs in a Pd Application Cylinder in step 57 . The sprayed tobacco cut filler is dried in a drying unit in step 59 . Finally, further processing of the dried tobacco cut filler is performed in step 61 , as shown in FIG. 2.
EXAMPLES
[0032] The following example test results are provided to experimentally verify the performance of the present invention. As shown in FIG. 3, five different test runs were made for a Palladium Application study. Each trial used standard tobacco cut filler. The first run, as shown in the “Control 1 ” example of FIG. 3, was processed as normal using standard casings, flavors and targets. The next series of tests, as shown in “Control 2 ,” “Control 3 ,” “Test 1 ,” and “Test 2 ” examples of FIG. 3, were planned to determine what starting OV was needed for application of palladium solution in order to achieve the best possible reductions in PAH's. The different starting OV's of the tobacco cut filler used were 12.5% and 21.5%. In each case either de-ionized water (i.e., see “Control 2 ” and “Control 3 ” of FIG. 3) or palladium solution (i.e., see “Test 1 ” and “Test 2 ” of FIG. 3) were applied. The amount of palladium in solution was designed so that the final filler target of 750 ppm was achieved. The difference between how the two different starting OV's were processed required that the filler be dried down to 12.5% (i.e., see “Control 2 ” and “Test 1 ” of FIG. 3) from its normal exit cutter OV of 21.5%. Therefore, additional handling and processing was required in order to complete the testing using a starting OV of 12.5%.
[0033] Following the first standard control test, two control tests (i.e., “Control 2 ” and “Control 3 ” of FIG. 3) were run with de-ionized water applied to the tobacco cut filler at a starting OV of 12.5% and 21.5%, respectively. Finally, two palladium application tests (i.e., “Test 1 ” and “Test 2 ” of FIG. 3) were run at the different starting OV's. For each of the two tests using de-ionized water and the two tests with palladium solution the moisture of the tobacco cut filler exiting the application cylinder was measured to be around 30%.
[0034] FIG. 4 is an exemplary flow diagram for the method of casing train measurement. The palladium solution used was a concentrated potassium tetrachloropalladate (K2PdC14) as indicated at the Pd Casing Tank of FIG. 4. The concentration of the solution was diluted with de-ionized water. The amount of dilution depends on the concentration of Pd in the initial solution that is required to achieve a final Pd filler target of 750 ppm. This high exiting OV required that the filler be dried down to proper levels prior to final processing. Samples were taken at several key points in the process as indicated by references A, 1 of FIG. 4. In addition, references B and D refer to locations used for sampling filler to be analyzed. Further, reference 2 refers to sample points where wipe samples were taken. This included Exit Cutter, Exit Dryer (1st pass), Exit Final Weighbelt (1st pass), Exit Dryer (2nd pass) and Exit Final Weighbelt (2nd pass).
[0035] An explanation is required regarding the sample locations A, 1 of FIG. 4 for the different tests. Since the first standard control test was processed under normal conditions the sampling locations were Exit Cutter (1 st pass), Exit Dryer (1 st pass) and Exit Final Weighbelt (1 st pass). For the tests using a starting OV of 12.5%, the sampling locations were Exit Cutter, Exit Dryer (1 st pass), Exit Final Weighbelt (1 st pass), Exit Dryer (2 nd pass) and Exit Final Weighbelt (2 nd pass). For the tests using a starting OV of 21.5%, the sampling locations were Exit Cutter, Exit Final Weighbelt (1 st pass), Exit Dryer (2 nd pass) and Exit Final Weighbelt (2 nd pass). Therefore, for comparison purposes, the Exit Dryer (1 st pass) for the first standard control test and the Exit Dryer (2 nd pass) for all the other runs are equivalent.
[0036] In general, filler samples were tested for a variety of constituents. The filler was tested for levels of Pd, pH, PG, Glycerin, Total reducing sugars, Glycyrrhizic acid, Theobromine, Total alkaloids, Sugars (individual-fructose, glucose and sucrose), Nitrate Nitrogen, Phosphorus, Soluble Ammonia, TSNA's and OV's. All results are displayed on a dry weight basis. Cigarettes were made from the filler from each run. The cigarettes were tested for PAHs, TSNAs, Phenols, VOCs, and Carbonyls. All data was put on a per mg/Tar (FTC) basis.
[0037] FIG. 5 is an exemplary flow diagram for the method of drying train measurement. Once the tobacco filler was sprayed with the palladium solution, it was fed back to be dried and then to have final flavoring and processing completed. Samples were taken at several points in the process as indicated by references A and 1 of FIG. 5. Sample locations C, D refer to the locations where cut filler samples were taken for filler analysis. Sample locations at references 3 , 4 , 5 refer to locations where wipe samples were taken to have analyzed for palladium levels for purpose of effectiveness before and after cleaning of equipment. The description of casing and drying train measurements is discussed above.
[0038] In particular, FIG. 6, FIG. 7 and FIG. 8 address detailed results for Pd level, pH level and Nitrate Nitrogen tests. Overall, test results would help to determine what effect the additional drying step from using a starting OV of 12.5% had as well as the possible effect of palladium on additional processing, casings and flavors. It should also be noted that although the same tobacco was used for each run that the starting levels of some constituents varied greatly. However, in the comparison between the tests the change from exit cutter to exit final Weighbelt was measured and compared. This step allows a true comparison for any changes between tests.
[0039] The data in FIG. 6 shows that final filler target of 750 ppm Pd was achieved for the starting OV test of 21.5% (785 ppm), however, was slightly higher for the 12.5% OV test (866 ppm). The reason for the slightly higher level is due to differences in expected OV's exit dryer. However, the results of FIG. 6 show that this did not have a net difference on the overall analysis.
[0040] FIG. 7 shows that, although the pH of the palladium salt solution is approximately 3.3, the pH of the palladium salt solution did not seem to have an effect on the pH of the overall filler as compared to the controls using either de-ionized (DI) water or the first standard control test. The final pH of the standard filler was 5.56 while the pH levels for the 12.5% and 21.5% were 5.52 and 5.57, respectively.
[0041] FIG. 8 shows the results of the Nitrate Nitrogen tests. For nitrate nitrogen there did not seem to be any difference between the first standard control test run and the run at 21.5%. The run at 12.5% did show a larger decrease in the nitrate nitrogen level than the other tests even though the starting level was identical to the first standard control test run and the other palladium run.
[0042] In addition to the results discussed above, it has been determined that there is a point at which adding more palladium may not increase PAH reduction. Further, wipe sample data shows that in order to clean equipment and run another product (i.e., non-palladium) requires extensive cleaning. Thus, most likely a separate line should be used for processing palladium filler.
[0043] In a separate test, Metals in Smoke were examined. TABLE 1 below shows the results of these tests. A test was run to determine if the amount of Pd applied to tobacco cut filler affected different smoke constituents. For example, the levels of certain heavy metals are listed below. The only difference between the control and test conditions is the palladium that is applied. The control included only spraying de-ionized water not a palladium solution in order to that all tests achieved a similar final wetted OV for the tobacco cut filler.
[0000]
TABLE 1
METALS IN SMOKE TEST RESULTS
Control
500 PPM
600
750
1000 PPM
Arsenic
2.4
1.6
1.4
1.4
1.3
Cadmium
21.8
14.8
12.5
12.5
10.3
(ng/cigt)
Lead (ng/cigt)
7.2
<3.30
<3.30
<3.30
<3.30
Reductions in Arsenic ranged from 33 to 46%. Cadmium ranged from 32 to 53%. Lead was reduced by at least 56% (LOD was limited to 3.30 ng/cigt).
[0044] The foregoing description illustrates and describes the present invention. Additionally, the disclosure shows and describes only the preferred embodiments of the invention, but as mentioned above, it is to be understood that the invention is capable of use in various other combinations, modifications, and environments and is capable of changes or modifications within the scope of the inventive concept as expressed herein, commensurate with the above teachings and/or skill or knowledge of the relevant art. The embodiments described hereinabove are further intended to explain best modes known of practicing the invention and to enable others skilled in the art to utilize the invention in such, or other embodiments and with the various modifications required by the particular applications or uses of the invention. Accordingly, the description is not intended to limit the invention to the form or application disclosed herein. Also, it is intended that the appended claims be construed to include alternative embodiments. | An apparatus and method for the process of applying palladium salts to tobacco cut filler and other smokable products so that polycyclic aromatic hydrocarbons (PAHs) can be reduced in both mainstream (MS) and sidestream (SS) cigarette smoke. The reduction in PAHs is observed in the total particulate matter (TPM) of the mainstream (MS) and sidestream (SS) smoke. Additionally, substantial reductions in heavy metals and Ames biological activity can be achieved when the palladium salt solution is applied and processed in accordance with the present invention. The present invention provides these improvements by using a preferred ratio of palladium (Pd) salt to Chloride (Cl) that is specifically designed to allow for high palladium solubility. Further, the present invention provides an apparatus and method for applying the palladium salt solution while minimizing the number of processing steps required | 0 |
TECHNICAL FIELD
[0001] The present invention relates to a natural stone development method which enables natural stones used particularly on exterior wall and interior wall coatings to be mounted easily.
BACKGROUND OF THE INVENTION
[0002] Today coating is performed by mounting natural stones and so on mechanically to surfaces, walls or facades particularly in high buildings because of their advantages. A material similar to hollow profile is placed which is mounted upon being suspended on column, wall and similar parts of a building in order that firstly the coating member is mounted to the building during coating. By means of the said material, isolation material can be placed between building and coating member easily.
[0003] A connection piece which may have various shapes is mounted on profiles mounted in a hollow way. In order that the said piece and the natural stone, in other words the coating member, are coupled; holes or channels with various depths are usually made on corresponding long parallel edges and connection between the afore-mentioned piece and the connection piece is realized by placing coupling members such as pin, bar to the said holes. Then the holes are fixed upon being filled with adhesive material optionally or fixed using a material, which is known in the state of the art, called as silicone sheath. In the event that, the said coupling technique is used, it is required to leave joint space between the pieces because of the coupling members. This has two major disadvantages in general terms. Firstly, the fact that the said hole is filled with a joint filling material primarily leads to great expense of workmanship and material and also renewal and maintenance costs in years. The second disadvantage is due to the fact that resistance of material decreases and it wears off in time because of exposure to environmental factors such as rain, wind in the event that the holes remain open.
[0004] If it is not desired to leave joint space in the said coupling technique; preferably the members with a blind-ended tip having a bolt shape are fixed to grooves, which are located on the back surface to the back surface of the natural stone in other words the coating member and opened through an additional processing by means of an adhesive. The members fixed to the rear surface of the stone are fixed to connection pieces, which are located on the hollow profile, by means of connection members such as nut preferably. Because the said process is carried out under construction site conditions it leads to loss of workmanship, time and waste.
[0005] In using natural stone or another material on facade coatings, adjustments allow thickness of 3 centimetres at minimum due to natural conditions. And this leads to difficulty of transportation and installation resulting from weight.
[0006] In another method used in the state of the art, coupling is provided by pushing the material among the lip-like structure which is mounted mutually by opening channel thoroughly on the sides thereof with 3 centimetres thickness. And this leads to the fact that a dimensional difference in profile and building facade is reflected on surface and integrity of surface and level cannot be ensured.
[0007] The Chinese patent document no. CN101793083 discloses a connectable natural stone and a production method of this natural stone. The said natural stone comprises: a stone body which has a polished flat surface provided with a groove on thereof; a resin inside the groove; and a connection which is formed between the groove and the resin along the groove direction. The connectable natural stone comprises steps of: polishing one surface of the natural stone to be flat and forming a groove on this surface; putting a rod-like die, which is immiscible with the resin inside the groove, wherein two ends thereof extend out of two ends of the groove; fully filling the groove with heated and melted resin and drawing the rod-like die out of the groove when the resin is cooled and subjecting it to a certain degree to form a connection. The connecting hole is formed on the natural stone and the fixed part is placed on the connecting hole.
[0008] The Japanese patent document no. JPH10237846 discloses a natural stone block. There is a hole provided on the natural stone. An adhesive is filled into the said hole and a reinforcement in form of a deformed bar is buried and fixed to the said hole.
SUMMARY OF THE INVENTION
[0009] An objective of the present invention is to realize a natural stone development method which enables natural stones used particularly on exterior wall and interior wall and all kinds of coatings to be mounted easily.
[0010] Another objective of the present invention is to realize a method which enables to reinforce natural stones used on facade or wall coatings.
[0011] Another objective of the present invention is to realize a method which enables to reduce cost of workmanship occurring during facade or wall coatings.
[0012] Another objective of the present invention is to realize a method which enables to reduce loss of time and waste experienced during facade or wall coatings.
[0013] Another objective of the present invention is to realize a method which enables to prevent cracks that may occur on the coating material provided on the coated facade or wall in time.
DETAILED DESCRIPTION OF THE INVENTION
[0014] “A development method for mounting natural stones on facade coatings easily” realized to fulfill the objectives of the present invention is shown in the figure attached, in which:
[0015] FIG. 1 is a flowchart of the inventive method.
[0016] The inventive method ( 100 ) comprises steps of:
opening at least one channel on the back surface of natural stone block ( 101 ); placing reinforcement and suspension member, wherein connection members which ensure fixing onto the connection pieces located on the wall whereon coating will be made, into the channels opened on the block ( 102 ).
[0019] In the inventive method ( 100 ); at least one channel is opened on the natural stone, which will be used in facade coating, surface that is not visible from outside when it is coated by means of any method in the state of the art ( 101 ). The said channel can have regular geometrical shapes such as cylindrical, spherical or irregular shapes such as grid pattern or spiral. Depth of the channel opened on the natural stone can have any depth which depends on thickness of the natural stone and varies from application to application. After channel is opened on the natural stone ( 101 ); reinforcement and suspension member, wherein connection members which ensure fixing onto the connection pieces located on the wall whereon coating will be made, are placed into the channels opened ( 102 ). The reinforcement and suspension member, which is embedded into the channel opened on the natural stone, is a profile thickness of which can be adjusted based on the thickness of the natural stone; has a thickness between preferably 3 to 10 millimetres; manufactured from an organic or inorganic material such as aluminium or glass fiber; and has high strength in the inventive method ( 100 ). Shape of the said reinforcement and suspension member is equal or too close to the shape of the channel opened on the natural stone. In a preferred embodiment of the invention, the reinforcement and suspension member has a thickness equal to the thickness of the channel opened or less than it. In a preferred embodiment of the invention, the reinforcement and suspension member is attached into the channel by means of an organic or inorganic adhesive such as epoxy or polyester. With the connection members located on various points of the reinforcement and suspension member, the natural stone can be coupled by any suspension system in the state of the art and thus it is save on both workmanship and time during facade coating. In a preferred embodiment of the invention, the connection piece provided on the reinforcement and suspension member is preferably a suspension-bolt system.
[0020] The reinforcement and suspension member used in the inventive method ( 100 ) has a shape which is identical or very similar with a slot such as channel, grid located behind the natural stone. The reinforcement and suspension member is a single piece in a preferred embodiment of the invention and coupling pieces which can be coupled to each other is obtained in order to increase number of connection members on thereof in alternative embodiments of the invention. Amount of load which can be taken and carried (tolerable) in a point way is increased by means of increasing the number of connection members on the reinforcement and suspension member. In addition to this, the coating material also strengthens structurally upon the number of connection members increases. Thickness of the said reinforcement and suspension member can change in itself, connection members are not located in symmetrical places and one of them can be located at the top and the other can be located at the bottom. In an embodiment of the invention, the reinforcement and suspension member has a rough surface so that the surface adsorption can be enhanced.
[0021] Due to the fact that durability and strength of natural stone, which is obtained by placing the reinforcement and suspension member to the channels formed on thereof, is enhanced by means of the reinforcement and suspension member with the inventive method ( 100 ); natural stones having dimensions thinner than coating members in the state of the art can be used in coating process. Thus, problems that may occur due to weight of natural stone in transportation and installation are avoided.
[0022] With the inventive method ( 100 ), no thickness difference occurs on the natural stone surface because the actual mounting holes of the natural stone obtained by placing the reinforcement and suspension member to the channels formed on thereof are connected to the reinforcement and suspension member located in the natural stone. Therefore, a substantial convenience is provided in packaging and transportation processes.
[0023] It is possible to develop various embodiments of the inventive method ( 100 ), it cannot be limited to examples disclosed herein and it is essentially according to claims. | The present invention relates to a natural stone development method which enables natural stones used particularly on exterior wall and interior wall and all kinds of coatings to be mounted easily. With the inventive method, natural stones used on wall coatings are reinforced. In addition; the inventive method also enables to reduce cost of workmanship occurring during facade or wall and all kinds of coatings, loss of time and waste experienced. | 4 |
PRIORITY
[0001] This application claims priority under 35 U.S.C. § 119 to an application entitled “Apparatus and Method for Encoding/Decoding Space-Time Low Density Parity Check Code with Full Diversity Gain” filed in the Korean Intellectual Property Office on Feb. 6, 2004 and assigned Serial No. 2004-7978, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to a mobile communication system, and in particular, to an apparatus and method for encoding and decoding a space-time Low Density Parity Check (LDPC) code having a full diversity gain.
[0004] 2. Description of the Related Art
[0005] In communications, it is most important to efficiently and reliably transmit data over a channel. In the next generation multimedia mobile communication into which active research is currently being made, it is necessary to increase system efficiency using a channel coding technique appropriate for the system, as there is an increased demand for a high-speed communication system capable of processing and transmitting a variety of information such as image and radio data beyond that of the early voice-oriented service.
[0006] Unlike a wired channel environment, a wireless channel environment existing in a wireless communication system inevitably from suffers errors caused by various conditions such as multipath interference, shadowing, propagation attenuation, interference, and fading. These errors commonly cause an information loss in the transmitted data. The information loss seriously distorts actual transmission signals, causing a reduction in entire performance of the mobile communication system.
[0007] Generally, in order to reduce the information loss, various error-control techniques are used according to characteristics of channels to increase reliability of the mobile communication system. The most typical error-control technique uses an error correction code.
[0008] Mobile communication systems use diversity schemes in order to remove communication instability caused by fading, and a space diversity scheme, one of the diversity schemes, uses multiple antennas.
[0009] Generally, the space diversity schemes are classified into a reception diversity scheme using multiple reception antennas, a transmission diversity scheme using multiple transmission antennas, and a Multiple-Input Multiple-Output (MIMO) scheme using multiple reception antennas and multiple transmission antennas. The MIMO scheme is a kind of Space-Time Coding (STC) scheme, and the STC scheme extends a time-domain coding scheme to a space-domain coding scheme by transmitting signals encoded with a predetermined coding scheme using multiple transmission antennas, thereby achieving a low error rate.
[0010] FIG. 1 is a block diagram schematically illustrating a transmitter in a conventional mobile communication system using an STC scheme. Referring to FIG. 1 , the transmitter includes an encoder 110 , a spatial mapper 120 , a plurality of signal mappers of first to M th signal mappers 130 - 1 -to 130 -M, and a plurality of transmission antennas (Tx.ANT) of first to M th transmission antennas Tx.ANT# 1 to Tx.ANT#M.
[0011] Upon receiving information data, the encoder 110 encodes the received information data into coded symbols at a predetermined coding rate with a predetermined coding scheme, and outputs the coded symbols to the spatial mapper 120 . For example, if the information data is comprised of k bits and the coding rate is k/N, the encoder 110 encodes the k-bit information data into N coded symbols.
[0012] The spatial mapper 120 spatial-maps the coded symbols output from the encoder 110 with a predetermined spatial mapping scheme such that the coded symbols can be transmitted via the M transmission antennas, and outputs the spatial-mapped signals to their associated signal mappers. There are various possible spatial mapping schemes used by the spatial mapper 120 , and it will be assumed in FIG. 1 that the spatial mapper 120 spatial-maps the coded symbols output from the encoder 110 in their output order. For example, if it is assumed that a coded symbol stream output from the encoder 110 is C=[c1,c2, . . . ,c N ], an output of the spatial mapper 120 becomes an
M × N M
space-time codeword matrix defined as Equation (1).
C = [ c 1 c M + 1 … c N - M + 1 c 2 c M + 2 … c N - M + 2 … c M c M + M … c N ] ( 1 )
[0013] Because the number of the transmission antennas is M, the spatial mapper 120 sequentially spatial-maps the coded symbols output from the encoder 110 in their output order, divides the spatial-mapped symbols into M signals, and outputs the M signals to the first to M th signal mappers 130 - 1 to 130 M associated thereto. The first to M th signal mappers 130 - 1 to 130 -M each signal-map the signals output from the spatial mapper 120 with a predetermined signal mapping scheme, and transmit the signal-mapped signals over the air via their associated transmission antennas Tx.ANT# 1 to Tx.ANT#M. Here, the first to M th signal mappers 130 - 1 to 130 -M each signal-map input signals according to a constellation for the predetermined signal mapping scheme, and output the signal-mapped signals to the first to M th transmission antennas Tx.ANT# 1 to Tx.ANT#M, respectively. Each of the first to M th signal mappers 130 - 1 to 130 -M signal-maps an input signal with a Binary Phase Shift Keying (BPSK) scheme, which shifts a phase in association with a transmission sign using a carrier having constant amplitude and phase, if the number of bits constituting the input signal is n=1; signal-maps the input signal with a Quadrature Phase Shift Keying (QPSK) scheme, if the number of bits constituting the input signal is n=2; and signal-maps the input signal with an 8-ary Quadrature Amplitude Modulation (8QAM) scheme if the number of bits constituting the input signal is n=3.
[0014] In FIG. 1 , because k-bit information data is transmitted via M transmission antennas, its coding rate is
M × k M .
[0015] FIG. 2 is a block diagram schematically illustrating a receiver in a conventional mobile communication system using an STC scheme. Referring to FIG. 2 , the receiver includes a plurality of reception antennas Rx.ANT of first to P th reception antennas Rx.ANT# 1 to Rx.ANT#P, a detector 210 , a spatial demapper 220 , a space-time decoder 230 , and a spatial mapper 240 . Although it is assumed in FIG. 2 that the number P of reception antennas in the receiver is different from the number M of transmission antennas in the transmitter, the number of reception antennas in the receiver may be equal to the number of transmission antennas in the transmitter.
[0016] The signals transmitted by the transmitter via a plurality of transmission antennas (the first to M th transmission antennas Tx.ANT# 1 to Tx.ANT#M) are received at the receiver through the first to P th reception antennas. The first to P th reception antennas output their received signals to the detector 210 . The detector 210 detects transmission signals transmitted by the first to M th transmission antennas from the received signals output from the first to P th reception antennas, and outputs the detected transmission signals to the spatial demapper 220 .
[0017] The spatial demapper 220 spatial-demaps the signals output from the detector 210 with a spatial demapping scheme corresponding to the spatial mapping scheme used in the transmitter, and outputs the spatial-demapped signal to the space-time decoder 230 . The space-time decoder 230 decodes the signal output from the spatial-demapper 220 with a decoding scheme corresponding to the coding scheme used in the transmitter. When there is no error caused by the wireless channel environment, the signal output from the space-time decoder 230 is equal to the information data in the transmitter. Actually, however, because errors occur in the wireless channel environment, the space-time decoder 230 can perform iterative decoding for reliable decoding.
[0018] For the iterative decoding, the space-time decoder 230 outputs the signal decoded with a decoding scheme corresponding to the coding scheme used in the transmitter, to the spatial mapper 240 . The spatial mapper 240 spatial-maps the signal output from the space-time decoder 230 with a spatial mapping scheme corresponding to the spatial mapping scheme used in the transmitter, and outputs the spatial-mapped signal to the detector 210 in order to perform iterative decoding. The application of the iterative decoding increases the decoding reliability of information data. Thereafter, the signal decoded in the space-time decoder 230 through the iterative decoding is output as the information data.
[0019] The term “space-time code” refers to a code encoded with the STC scheme, and the STC scheme, as described above, supplementally acquires additional information by extending a time-domain coding scheme to a space-domain coding scheme. That is, the STC scheme not only reduces an error rate by providing additional information in the time domain, but also increases a diversity gain in the space domain, thereby enabling correct signal decoding. Because the diversity gain corresponds to a slope of a signal-to-noise ratio (SNR) and an error rate of a space-time code, expressed with a log scale, when the space-time code is designed, maximization of the diversity gain (hereinafter, referred to as “full diversity gain”) is the most important factor for determining performance of the space-time code.
[0020] In order to acquire the full diversity gain, the following Space-Time Code Design Conditions 1-3 should be satisfied in a process of designing the space-time code.
[0021] Space-Time Code Design Condition 1
[0022] In order to obtain the full diversity gain, a matrix B(c,e) should have a full rank for particular space-time codeword ‘c’ and space-time codeword ‘e’. Here, the matrix B(c,e) is a matrix representing a difference between the space-time codeword ‘c’ and the space-time codeword ‘e’.
[0023] Space-Time Code Design Condition 2 should be satisfied, especially when signals are mapped using the BPSK scheme.
[0024] Space-Time Code Design Condition 2
[0025] A space-time codeword has a full diversity gain, when all non-zero space-time codeword matrixes ‘c’ have a full rank in a binary field.
[0026] Space-Time Code Design Condition 3 should be satisfied, especially when signals are mapped using the QPSK scheme.
[0027] Space-Time Code Design Condition 3
[0028] A space-time codeword has a full diversity gain, when a space-time codeword matrix Φ(c) obtained by mapping all non-zero space-time codeword matrixes ‘c’ in a binary field has a full rank.
[0029] As described above, the space-time code is designed to have a full rank in order to acquire a full diversity gain. That is, the space-time code is designed such that its generation matrix (G) has a full rank.
[0030] The next generation communication system is developing into an advanced communication system providing high-speed, high-capacity data services having various qualities-of-service (QoS). In the high-speed, high-capacity data services, an information loss during transmission is fatal to the services. Therefore, error correction capability of the error correction code functions as an important factor of determining the entire QoS. Typically, the error correction code includes a turbo code and a low density parity check (LDPC) code.
[0031] It is well known that the LDPC code is superior in performance gain to a convolutional code that is conventionally used for error correction, during high-speed data transmission. More specifically, the LDPC code is advantageous in that it can efficiently correct an error caused by noises occurring in a wireless channel, thereby increasing the reliability of data transmission. In addition, the LDPC code can be decoded using an iterative decoding algorithm based on a sum-product algorithm on a factor graph. Because a decoder for the LDPC code uses the sum-product algorithm-based iterative decoding algorithm, it is lower in complexity to a decoder for the turbo code. In addition, the decoder for the LDPC code is easy to implement a parallel processing decoder, as compared with the decoder for the turbo code.
[0032] The turbo code has excellent performance approximating a channel capacity limit of Shannon's channel coding theorem, and the LDPC code known to have the highest performance shows performance having a difference of only about 0.04 [dB] at a channel capacity limit of Shannon's channel coding theorem at a bit error rate (BER) 10 −5 , using a block size 10 7 . Shannon's channel coding theorem shows that reliable communication is possible only at a data rate not exceeding a channel capacity.
[0033] Generally, although a random code having a very large block size shows performance approximating a channel capacity limit of Shannon's channel coding theorem, when a MAP (Maximum A Posteriori) or ML (Maximum Likelihood) decoding method is used, it is actually impossible to implement the decoding method because of its heavy calculation load.
[0034] The LDPC code is defined by a parity check matrix in which the majority of elements have a zero value and a minority of elements except the elements having the zero value has a non-zero value, for example, a value of 1. In the following description, it will be assumed that a non-zero value is a value of 1. Because the parity check matrix of the LDPC code has a small weight, it is possible to perform decoding through iterative decoding even in a block code having a relatively long length. If a block length of the block code is continuously increased, the block code exhibits performance approximating a capacity limit of a Shannon channel, like the turbo code. Herein, the term “weight” refers to the number of elements having a non-zero value among the elements constituting the parity check matrix. Therefore, the next generation communication system tends to actively use the LDPC code as the error correction code.
[0035] However, when the LDPC code performs encoding using the generation matrix like the space-time code, performance of the LDPC code cannot be guaranteed. That is, the LDPC code, as described above, is advantageous in that it has low decoding complexity because of the small weight of the parity check matrix, but when the parity check matrix is converted to a generation matrix, a weight of the generation matrix increases, causing an increase in decoding complexity.
[0036] As a result, when the space-time code is designed using the LDPC code, it is difficult to apply the foregoing design conditions proposed for the generation matrix of a general space-time code. Therefore, there is a demand for a scheme in which a space-time code using the LDPC code can acquire the full diversity gain, i.e., for a parity check matrix capable of acquiring the full diversity gain.
SUMMARY OF THE INVENTION
[0037] It is, therefore, an object of the present invention to provide an apparatus and method for encoding and decoding a space-time LDPC code acquiring a full diversity gain in a mobile communication system.
[0038] It is another object of the present invention to provide an apparatus and method for encoding and decoding a space-time LDPC code having a correlation between a plurality of transmission antennas in a mobile communication system using the plurality of transmission antennas.
[0039] It is further another object of the present invention to provide a method for designing a parity check matrix of a space-time LDPC code acquiring a full diversity gain in a mobile communication system.
[0040] In accordance with one aspect of the present invention, there is provided a method for generating a parity check matrix of a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The method comprises the steps of determining a size of a parity check matrix such that the size of the parity check matrix corresponds to a coding rate used when information data is encoded into a space-time LDPC code; determining a length of a codeword of the space-time LDPC code; dividing the parity check matrix having the determined size into a first partial matrix corresponding to the information data and a second partial matrix corresponding to a parity corresponding to the information data; generating a third partial matrix having even-numbered columns of the first partial matrix; generating a fourth partial matrix having odd-numbered columns of the second partial matrix; generating a fifth partial matrix obtained by combining the third partial matrix with the fourth partial matrix; generating a sixth partial matrix having odd-numbered columns of the first partial matrix; generating a seventh partial matrix having even-numbered columns of the second partial matrix; generating an eighth partial matrix obtained by combining the sixth partial matrix with the seventh partial matrix; generating a ninth partial matrix obtained by exclusive-ORing the first partial matrix and the second partial matrix; and generating the parity check matrix such that the fifth partial matrix and the eighth partial matrix have a predetermined rank in the ninth partial matrix and a binary field.
[0041] In accordance with another aspect of the present invention, there is provided a method for generating a parity check matrix of a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The method comprises the steps of determining a size of a parity check matrix such that the size of the parity check matrix corresponds to a coding rate used when information data is encoded into a space-time LDPC code; determining a length of a codeword of the space-time LDPC code; dividing the space-time LDPC code into a real-part space-time LDPC code and an imaginary-part space-time LDPC code; dividing the real-part space-time LDPC code into a first codeword transmitted via a first transmission antenna and a second codeword transmitted via a second transmission antenna; dividing the imaginary-part space-time LDPC code into a third codeword transmitted via the first transmission antenna and a fourth codeword transmitted via the second transmission antenna; dividing the parity check matrix into a first partial matrix corresponding to the first codeword and the third codeword and a second partial matrix corresponding to the second codeword and the fourth codeword; and generating the parity check matrix such that the first partial matrix, the second partial matrix, and a third partial matrix obtained by exclusive-ORing the first partial matrix and the second partial matrix have a predetermined rank in a binary field.
[0042] In accordance with further another aspect of the present invention, there is provided a method for encoding a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The method comprises the steps of receiving information data; generating an LDPC code by encoding the information data such that a fifth partial matrix obtained by combining a second partial matrix having even-numbered columns of a first partial matrix corresponding to the information data with a fourth partial matrix having odd-numbered columns of a third partial matrix corresponding to a parity, and an eighth partial matrix obtained by combining a sixth partial matrix having odd-numbered columns of the first partial matrix with a seventh partial matrix having even-numbered columns of the third partial matrix correspond to a ninth partial matrix obtained by exclusive-ORing the first partial matrix and the third partial matrix and a parity check matrix having a predetermined rank in a binary field; and generating a space-time LDPC code by spatial-mapping the LDC code according to a predetermined spatial mapping scheme.
[0043] In accordance with further another aspect of the present invention, there is provided a method for encoding a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The method comprises the steps of receiving information data; generating an LDPC code by encoding the information data such that a first partial matrix corresponding to a first codeword and a third codeword, a second partial matrix corresponding to a second codeword and a fourth codeword, and a third partial matrix obtained by exclusive-ORing the first partial matrix and the second partial matrix correspond to a parity check matrix having a predetermined rank in a binary field; and generating a space-time LDPC code by spatial-mapping the LDPC code according to a predetermined spatial mapping scheme; wherein the space-time LDPC code is divided into a real-part space-time LDPC code and an imaginary-part space-time LDPC code, the real-part space-time LDPC code is divided into a first codeword transmitted via a first transmission antenna among the plurality of transmission antennas and a second codeword transmitted via a second transmission antenna among the plurality of transmission antennas, and the imaginary-part space-time LDPC code is divided into a third codeword transmitted via the first transmission antenna and a fourth codeword transmitted via the second transmission antenna.
[0044] In accordance with further another aspect of the present invention, there is provided an apparatus for encoding a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The apparatus comprises an LDPC encoding part for receiving information data, and encoding the information data into an LDPC code according to a control signal; a spatial mapper for generating a space-time LDPC code by spatial-mapping the LDPC code according to a predetermined spatial mapping scheme; and a controller for generating the LDPC code by encoding the information data such that a fifth partial matrix obtained by combining a second partial matrix having even-numbered columns of a first partial matrix corresponding to the information data with a fourth partial matrix having odd-numbered columns of a third partial matrix corresponding to a parity, and an eighth partial matrix obtained by combining a sixth partial matrix having odd-numbered columns of the first partial matrix with a seventh partial matrix having even-numbered columns of the third partial matrix correspond to a ninth partial matrix obtained by exclusive-ORing the first partial matrix and the third partial matrix and a parity check matrix having a predetermined rank in a binary field.
[0045] In accordance with further another aspect of the present invention, there is provided an apparatus for encoding a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The apparatus comprises a space-time LDPC encoder for receiving information data, encoding the information data into an LDPC code according to a control signal, and generating a space-time LDPC code by spatial-mapping the LDPC code according to a predetermined spatial mapping scheme; and a controller for generating an LDPC code by encoding the information data such that a first partial matrix corresponding to a first codeword and a third codeword, a second partial matrix corresponding to a second codeword and a fourth codeword, and a third partial matrix obtained by exclusive-ORing the first partial matrix and the second partial matrix correspond to a parity check matrix having a predetermined rank in a binary field; wherein the space-time LDPC code is divided into a real-part space-time LDPC code and an imaginary-part space-time LDPC code, the real-part space-time LDPC code is divided into a first codeword transmitted via a first transmission antenna among the plurality of transmission antennas and a second codeword transmitted via a second transmission antenna among the plurality of transmission antennas, and the imaginary-part space-time LDPC code is divided into a third codeword transmitted via the first transmission antenna and a fourth codeword transmitted via the second transmission antenna.
[0046] In accordance with further another aspect of the present invention, there is provided a method for decoding a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The method comprises the steps of: (a) detecting a reception signal from signals received via corresponding reception antennas; (b) performing spatial mapping node decoding based on a detected value of the received signals; (c) decoding the spatial-mapped-node-decoded signal according to a predetermined parity check matrix; (d) if probability values of the signals decoded according to the parity check matrix satisfy a predetermined iterative decoding stop condition, hard-deciding the probability values and outputs the hard-decided probability values as information data; and (e) if the probability values do not satisfy the iterative decoding stop condition, repeatedly performing the steps (b) and (c) until the probability values satisfies the iterative decoding stop condition.
[0047] In accordance with further another aspect of the present invention, there is provided an apparatus for decoding a space-time low density parity check (LDPC) code in a mobile communication system including a transmitter using a plurality of transmission antennas and a receiver using a plurality of reception antennas. The apparatus comprises a detector for detecting a reception signal from signals received via corresponding reception antennas; a spatial mapping node decoder for performing spatial mapping node decoding based on a detected value of the received signals; an LDPC decoding part for decoding the spatial-mapped-node-decoded signal according to a predetermined parity check matrix; and a controller for performing a control operation such that if probability values of the signals decoded according to the parity check matrix satisfy a predetermined iterative decoding stop condition, the probability values are hard-decided and output as information data, and if the probability values do not satisfy the iterative decoding stop condition, the spatial mapping node decoding process and the decoding process are repeatedly performed until the probability values satisfies the iterative decoding stop condition.
BRIEF DESCRIPTION OF THE DRAWINGS
[0048] The above and other objects, features, and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:
[0049] FIG. 1 is a block diagram schematically illustrating a transmitter in a conventional mobile communication system using an STC scheme;
[0050] FIG. 2 is a block diagram schematically illustrating a receiver in a conventional mobile communication system using an STC scheme;
[0051] FIG. 3 is a diagram illustrating a parity check matrix of a conventional (8, 2, 4) LDPC code;
[0052] FIG. 4 is a diagram illustrating a factor graph of the (8, 2, 4) LDPC code illustrated in FIG. 3 ;
[0053] FIG. 5 is a block diagram schematically illustrating a transmitter according to an embodiment of the present invention, wherein a BPSK scheme is used as a signal mapping scheme;
[0054] FIG. 6 is a block diagram schematically illustrating a transmitter according to an embodiment of the present invention, wherein a QPSK scheme and a 4QAM scheme are used as a signal mapping scheme;
[0055] FIG. 7 is a flowchart illustrating an operation of a receiver in a mobile communication according to an embodiment of the present invention; and
[0056] FIG. 8 is a block diagram schematically illustrating a receiver in a mobile communication system according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0057] Preferred embodiments of the present invention will now be described in detail herein below with reference to the annexed drawings. In the following description, a detailed description of known functions and configurations incorporated herein has been omitted for conciseness.
[0058] The present invention proposes a scheme for encoding/decoding a space-time code using a low density parity check (LDPC) code as an error correction code (hereinafter referred to as a “space-time LDPC code”). In particular, the present invention proposes a scheme for encoding and decoding the space-time LDPC code having a full diversity gain.
[0059] Before a description of the present invention is given, the LDPC code will be described in detail. The LDPC code can be decoded using an iterative decoding algorithm based on a sum-product algorithm on a factor graph. Because a decoder for the LDPC code uses the sum-product algorithm-based iterative decoding algorithm, it is lower in complexity to a decoder for the turbo code. In addition, the decoder for the LDPC code is easy to implement a parallel processing decoder, compared with the decoder for the turbo code. When the LDPC code is expressed with a factor graph, there are cycles on the factor graph of the LDPC code, and it is well known that iterative decoding on the factor graph of the LDPC code where cycles exist is suboptimal. Also, it has been experimentally proven that the LDPC code has excellent performance through iterative decoding.
[0060] The LDPC code, proposed by Gallager, is defined by a parity check matrix in which the majority of elements have a zero value and a minority of elements except the elements having the zero value has a non-zero value, for example, a value of 1. In the following description, it will be assumed that a non-zero value is a value of 1.
[0061] Because the parity check matrix of the LDPC code has a small weight, it is possible to perform decoding through iterative decoding even in a block code having a relatively long length. If a block length of the block code is continuously increased, the block code exhibits performance approximating a capacity limit of a Shannon channel, like a turbo code. Herein, the term “weight” refers to the number of elements having a non-zero value among the elements constituting the parity check matrix. For example, an (N, j, k) LDPC code is a linear block code having a block length N, and is defined by a sparse parity check matrix in which each column has j elements having a value of 1, each row has k elements having a value of 1, and all of the elements except for the elements having the value of 1 have a value of 0.
[0062] FIG. 3 is a diagram illustrating a parity check matrix of a conventional ( 8 , 2 , 4 ) LDPC code as an example of an (N, j, k) LDPC code. Referring to FIG. 3 , a parity check matrix H of the (8, 2, 4) LDPC code includes 8 columns and 4 rows, wherein a weight of each column is fixed to 2 and a weight of each row is fixed to 4. Because the weight of each column and the weight of each row in the parity check matrix are regular as stated above, the (8, 2, 4) LDPC code becomes a regular LDPC code. However, if a weight of each column and a weight of each row in the parity check matrix are irregular, the LDPC code becomes an irregular LDPC code.
[0063] FIG. 4 is a diagram illustrating a factor graph of the (8, 2, 4) LDPC code of FIG. 3 . Referring to FIG. 4 , a factor graph of the (8, 2, 4) LDPC code includes 8 variable nodes of x 1 400 , x 2 402 , x 3 404 , x 4 406 , x 5 408 , x 6 410 , x 7 412 , and x 8 414 , and 4 check nodes 416 , 418 , 420 , and 422 . When an element having a value of 1, i.e., a non-zero value, exists at a point where an i th column and a j th row of the parity check matrix of the (8, 2, 4) LDPC code cross each other, a branch is created between a variable node x i and a j th check node.
[0064] Because the parity check matrix of the LDPC code has a very small weight, it is possible to perform decoding through iterative decoding even in a block code having a relatively long length, and if a block length of the block code is continuously increased, the block code exhibits performance approximating a capacity limit of a Shannon channel, like a turbo code. MacKay and Neal have proven that an iterative decoding process of an LDPC code using a flooding transfer technique is approximate to an iterative decoding process of a turbo code in terms of performance.
[0065] Accordingly, the present invention proposes a space-time LDPC encoding and decoding scheme capable of obtaining a full diversity gain when transmitting an LDPC code, thereby improving performance via a plurality of transmission antennas Tx.ANT.
[0066] FIG. 5 is a block diagram schematically illustrating a transmitter according to an embodiment of the present invention, wherein a Binary Phase Shift Keying (BPSK) scheme is used as a signal mapping scheme. Referring to FIG. 5 , the transmitter includes a serial-to-parallel (S/P) converter 500 , a memory 502 , a controller 504 , a first LDPC encoder (LDPC encoder # 1 ) 506 , a second LDPC encoder (LDPC encoder # 2 ) 508 , a spatial mapper 510 , a plurality of, for example, 2 signal mappers of first signal mapper (signal mapper # 1 ) 512 and second signal mapper (signal mapper # 2 ) 514 , and a plurality of transmission antennas Tx.ANT, for example, 2 of first and second transmission antennas Tx.ANT# 1 and Tx.ANT# 2 . It will be assumed herein that the first and second signal mappers 512 and 514 each perform signal mapping using the BPSK scheme.
[0067] The memory 502 stores a parity check matrix based on a space-time LDPC code design method proposed in the present invention. The parity check matrix based on the space-time LDPC code design method proposed in the present invention will be described in detail later. When information data ‘s’ is generated, the information data ‘s’ is delivered to the S/P converter 500 , and the S/P converter 500 parallel-converts the information data ‘s’ into first information data s 1 and second information data s 2 .
[0068] The first information data s 1 is input in common to the first LDPC encoder 506 and the spatial mapper 510 , and the second information data s 2 is input in common to the second LDPC encoder 508 and the spatial mapper 510 . The first LDPC encoder 506 , under the control of the controller 504 , encodes the first information data s 1 into an LDPC codeword, i.e., an LDPC coded symbol, according to a predetermined coding rate, and outputs the LDPC codeword to the spatial mapper 510 . The controller 504 controls the first LDPC encoder 506 according to the parity check matrix stored in the memory 502 such that the first LDPC encoder 506 generates an LDPC codeword corresponding to the parity check matrix. For example, if it is assumed that the first information data s 1 is comprised of k bits and the coding rate is ½, the number of bits output from the first LDPC encoder 506 becomes N=2k. Here, the LDPC codeword output from the first LDPC encoder 506 becomes a first parity p 1 , which is a part of a parity based on the entire information data ‘s’.
[0069] Similarly, the second LDPC encoder 508 , under the control of the controller 504 , encodes the second information data s 2 into an LDPC codeword, i.e., an LDPC coded symbol, according to a predetermined coding rate, and outputs the LDPC codeword to the spatial mapper 510 . The controller 504 controls the second LDPC encoder 508 according to the parity check matrix stored in the memory 502 such that the second LDPC encoder 508 generates an LDPC codeword corresponding to the parity check matrix. For example, if it is assumed that the second information data s 2 includes k bits and the coding rate is ½, the number of bits output from the second LDPC encoder 508 becomes N=2k. The LDPC codeword output from the second LDPC encoder 508 becomes a second parity p 2 , which is a part of a parity based on the entire information data ‘s’.
[0070] The parity check matrix stored in the memory 502 will be expressed as H, and the parity check matrix H is divided into an information part H s corresponding to the information data and a parity part H p corresponding to the parity, and can be expressed as shown in Equation (2).
H=[H s H p ] (2)
[0071] A size of the parity check matrix H is determined according to a coding rate of the transmitter and a size corresponding to a length of a space-time LDPC codeword, which is a final codeword. Herein, the 2-bit LDPC codeword output from the first LDPC encoder 506 will be referred to as a “first LDPC codeword c 1 ,” and the 2-bit LDPC codeword output from the second LDPC encoder 508 will be referred to as a “second LDPC codeword c 2 .” The first LDPC codeword c 1 includes a k-bit information codeword s 1 and a k-bit parity codeword p 1 , and the second LDPC codeword c 2 includes a k-bit information codeword s 2 and a k-bit parity codeword p 2 Therefore, the first LDPC codeword c 1 and the second LDPC codeword c 2 can be expressed as shown in Equation (3).
c 1 =[s 1 p 1 ]c 2 =[s 2 p 2 ] (3)
[0072] A relationship between the first LDPC codeword c 1 and the second LDPC codeword c 2 and the parity check matrix H is defined as shown in Equation (4).
H·c 1 =[H s H p ]·[s 1 p 1 ] T =0 H·c 2 =[H s H p ]·[s 2 p 2 ] T =0 (4)
[0073] The spatial mapper 510 spatial-maps the first LDPC codeword c 1 output from the first LDPC encoder 506 and the second LDPC codeword c 2 output from the second LDPC encoder 508 into space-time LDPC codewords C with a predetermined spatial mapping scheme, and outputs the space-time codewords C to their associated signal mappers so that the space-time codewords C are transmitted via the first and second transmission antennas, respectively. There are various spatial mapping schemes in which the spatial mapper 510 spatial-maps the first LDPC codeword c 1 and the second LDPC codeword c 2 . It will be assumed herein that the spatial mapper 510 performs spatial mapping based on a spatial mapping scheme described below.
[0074] The spatial mapper 510 performs spatial mapping such that an even-numbered information bit s e 1 constituting an information codeword s 1 of the first LDPC codeword c 1 output from the first LDPC encoder 506 , an even-numbered information bit s e 2 constituting an information codeword S 2 of the second LDPC codeword c 2 output from the second LDPC encoder 508 , an odd-numbered parity bit p 0 1 constituting a parity codeword p 1 of the first LDPC codeword c 1 output from the first LDPC encoder 506 , and an odd-numbered parity bit p 0 2 constituting a parity codeword p 2 of the second LDPC codeword c 2 output from the second LDPC encoder 508 are transmitted via the first transmission antenna. Further, the spatial mapper 510 performs spatial mapping such that an even-numbered parity bit p e 2 constituting a parity codeword p 2 of the second LDPC codeword c 2 output from the second LDPC encoder 508 , an even-numbered parity bit p e 1 constituting a parity codeword p 1 of the first LDPC codeword c 1 output from the first LDPC encoder 506 , an odd-numbered information bit s o 2 constituting an information codeword S 2 of the second LDPC codeword c 2 output from the second LDPC encoder 508 , and an odd-numbered information bit s o 1 constituting an information codeword s 1 of the first LDPC codeword c 1 output from the first LDPC encoder 506 are transmitted via the second transmission antenna.
[0075] When the first LDPC codeword c 1 and the second LDPC codeword c 2 are spatial-mapped in this manner, an output of the spatial mapper 510 becomes a space-time LDPC codeword C, which is a 2×k matrix, and can be expressed as shown in Equation (5).
C = [ s 1 e s 2 e p 1 o p 2 o p 2 e p 1 e s 2 o s 1 o ] ( 5 )
[0076] Because the first and second signal mappers 512 and 514 each signal-map input signals with the BPSK scheme, the space-time LDPC codeword C should satisfy a binary rank design rule. That is, as described above, if all non-zero space-time codeword matrixes have a full rank in a binary field, the space-time codeword has a full diversity gain. Therefore, in order to have a full diversity gain, the space-time LDPC codeword C should have a full rank in the binary field, and thus, the parity check matrix H should be designed to satisfy the following Parity Check Matrix Design Condition 1.
[0077] Parity Check Matrix Design Condition 1
[0078] H 1 =[H s e H p o ], H 2 =[H s o H p e ] and H s ⊕H p should have a full rank in the binary field.
[0079] In Parity Check Matrix Design Condition 1, the matrix H 1 =[H s e H p o ] is a matrix obtained by combining a matrix H s e having even-numbered columns in the matrix H s with a matrix H p o having odd-numbered columns in the matrix H p , and the matrix H 2 =[H s o H p e ] is a matrix obtained by combining a matrix H s o having odd-numbered columns in the matrix H s with a matrix H p e having even-numbered columns in the matrix H p . When the parity check matrix H is designed to satisfy Parity Check Matrix Design Condition 1 in this manner, signals transmitted via different transmission antennas of the transmitter are linearly independent of each other. Therefore, although a signal transmitted via any one of the transmission antennas experiences serious fading, a receiver can overcome an error caused by the fading.
[0080] The encoding process of the space-time LDPC code described in connection with FIG. 5 will be summarized herein below.
[0081] The parity check matrix H designed to satisfy Parity Check Matrix Design Condition 1 is stored in the memory 502 , and the controller 504 performs a control operation such that the first LDPC encoder 506 and the second LDPC encoder 508 each encode their input information data according to the parity check matrix H stored in the memory 502 . The spatial mapper 510 , under the control of the controller 504 , spatial-maps LDPC codewords ‘c’, i.e., the first LDPC codeword c 1 and the second LDPC codeword c 2 , output from the first LDPC encoder 506 and the second LDPC encoder 508 in their output order, and outputs the first LDPC codeword c 1 and the second LDPC codeword c 2 to the first signal mapper 512 and the second signal mapper 514 , respectively.
[0082] The first signal mapper 512 and the second signal mapper 514 each signal-map the signals output from the spatial mapper 510 with the BPSK scheme. The first signal mapper 512 transmits its signal-mapped signal over the air via the first transmission antenna, and the second signal mapper 514 transmits its signal-mapped signal over the air via the second transmission antenna.
[0083] FIG. 6 is a block diagram schematically illustrating a transmitter according to an embodiment of the present invention, wherein a Quadrature Phase Shift Keying (QPSK) scheme and a 4-ary Quadrature Amplitude Modulation (4QAM) scheme are used as the signal mapping scheme. Referring to FIG. 6 , the transmitter includes a serial-to-parallel (S/P) converter 600 , a memory 602 , a controller 604 , a real-part space-time LDPC encoder 606 , an imaginary-part space-time LDPC encoder 608 , a plurality of signal mappers, for example, 2, of first and second signal mappers 610 and 612 , and a plurality of transmission antennas, for example, 2, of first and second transmission antennas Tx.ANT# 1 and Tx.ANT# 2 . It will be assumed herein that the first and second signal mappers 610 and 612 each perform signal mapping using any one of the QPSK scheme and the 4QAM scheme.
[0084] The memory 602 stores a parity check matrix based on a space-time LDPC code design method proposed in the present invention. The parity check matrix based on the space-time LDPC code design method proposed in the present invention will be described in detail later.
[0085] Upon receiving information data ‘s’, the S/P converter 600 parallel-converts the information data ‘s’ into real-part information data s 1 and imaginary-part information data SQ.
[0086] The real-part information data s 1 is input to the real-part space-time LDPC encoder 606 , and the real-part space-time LDPC encoder 606 , under the control of the controller 604 , encodes the real-part information data s 1 into an LDPC codeword, i.e., an LDPC coded symbol, according to a predetermined coding rate, generates a space-time LDPC codeword by performing real-part space-time LDPC coding, and outputs the space-time LDPC codeword to the first signal mapper 610 and the second signal mapper 612 . The controller 604 controls the real-part space-time LDPC encoder 606 according to the parity check matrix stored in the memory 602 so that the real-part space-time LDPC encoder 606 generates a space-time LDPC codeword corresponding to the parity check matrix. For example, if it is assumed that the real-part information data s 1 includes k bits and the coding rate is ½, the number of bits output from the real-part space-time LDPC encoder 606 becomes N=2k. As a result, output data of the real-part space-time LDPC encoder 606 becomes a 2k-bit space-time LDPC codeword. The space-time LDPC codeword output from the real-part space-time LDPC encoder 606 is denoted by C 1 , and the space-time LDPC codeword C 1 is divided into C I 1 transmitted via the first transmission antenna and C I 2 transmitted via the second transmission antenna.
[0087] Also, the imaginary-part information data s Q is input to the imaginary-part space-time LDPC encoder 608 , and the imaginary-part space-time LDPC encoder 608 , under the control of the controller 604 , encodes the imaginary-part information data s Q into an LDPC codeword, i.e., an LDPC coded symbol, according to a predetermined coding rate, generates a space-time LDPC codeword by performing imaginary-part space-time LDPC coding, and outputs the space-time LDPC codeword to the first signal mapper 610 and the second signal mapper 612 . The controller 604 controls the imaginary-part space-time LDPC encoder 608 according to the parity check matrix stored in the memory 602 so that the imaginary-part space-time LDPC encoder 608 generates a space-time LDPC codeword corresponding to the parity check matrix. For example, if it is assumed that the imaginary-part information data s Q includes k bits and the coding rate is ½, the number of bits output from the imaginary-part space-time LDPC encoder 608 becomes N=2k. As a result, output data of the imaginary-part space-time LDPC encoder 608 becomes a 2k-bit space-time LDPC codeword. The space-time LDPC codeword output from the imaginary-part space-time LDPC encoder 608 is denoted by C Q , and the space-time LDPC codeword C Q is divided into C Q 1 transmitted via the first transmission antenna and C Q 2 transmitted via the second transmission antenna.
[0088] If the parity check matrix stored in the memory 602 is denoted by H, the parity check matrix H is divided into a first part H 1 corresponding to a codeword transmitted via the first transmission antenna and a second part H 2 corresponding to a codeword transmitted via the second transmission antenna. The first part H 1 and the second part H 2 constitute a space-time LDPC codeword, and can be expressed as shown in Equation (6).
H=[H 1 H 2 ] (6)
[0089] A size of the parity check matrix H is determined according to a coding rate of the transmitter and a size corresponding to a length of a space-time LDPC codeword, which is a final codeword. The space-time LDPC codeword C 1 generated from the real-part space-time LDPC encoder 606 and the space-time LDPC codeword C Q generated from the imaginary-part space-time LDPC encoder 608 can be expressed as shown in Equation (7).
C 1 = [ c I 1 c I 2 ] , C Q = [ c Q 1 c Q 2 ] ( 7 )
[0090] Here, a relationship between the space-time LDPC codeword C 1 and the space-time LDPC codeword C Q and the parity check matrix H is defined as shown in Equation (8).
H·C 1 =[H 1 H 2 ]·[c I 1 c I 2 ] T =0 H·C Q =[H 1 H 2 ]·[c Q 1 c Q 2 ] T =0 (8)
[0091] The first signal mapper 610 signal-maps the C I 1 output from the real-part space-time LDPC encoder 606 and the C Q 1 output from the imaginary-part space-time LDPC encoder 608 in accordance with Equation (9), and transmits the signal mapping result via the first transmission antenna.
( - 1 ( 2 ) ) C I 1 + j ( - 1 ( 2 ) ) C Q 1 ( 9 )
[0092] The second signal mapper 612 signal-maps the C 2 output from the real-part space-time LDPC encoder 606 and the C Q 2 output from the imaginary-part space-time LDPC encoder 608 in accordance with Equation (10), and transmits the signal mapping result via the first transmission antenna.
( - 1 ( 2 ) ) C I 2 + j ( - 1 ( 2 ) ) C Q 2 ( 10 )
[0093] In this case, a space-time LDPC codeword C, which is a 2×k matrix, can be expressed as shown in Equation (11).
C = [ c I 1 + j c Q 1 c I 2 + j c Q 2 ] ( 11 )
[0094] However, because the first signal mapper 610 and the second signal mapper 612 each perform signal mapping with any one of the QPSK scheme and the 4QAM scheme, the space-time LDPC codeword C should satisfy a QPSK binary rank design rule. That is, as described above, when all non-zero space-time codewords are mapped in a binary field, if the mapped space-time codeword has a full rank in the binary field, the space-time codeword has a full diversity gain. Therefore, in order to have a full diversity gain, the space-time LDPC codeword C should have a full rank in the binary field, and thus, the parity check matrix H should be designed so as to satisfy the following Parity Check Matrix Design Condition 2.
[0095] Parity Check Matrix Design Condition 2
[0096] The real-part space-time LDPC codeword C 1 and the imaginary-part space-time LDPC codeword C Q obtain a full diversity gain in the binary field, and H 1 , H 2 , and H 1 ⊕H 2 should have a full rank in the binary field.
[0097] In Parity Check Matrix Design Condition 2, the matrix H 1 denotes a parity matrix corresponding to a codeword transmitted via the first transmission antenna in the matrix H, and the matrix H 2 denotes a parity matrix corresponding to a codeword transmitted via the second transmission antenna in the matrix H.
[0098] The encoding process of the space-time LDPC code described in connection with FIG. 6 will be summarized herein below.
[0099] The parity check matrix H designed to satisfy Parity Check Matrix Design Condition 2 is stored in the memory 602 , and the controller 604 performs a control operation such that the real-part space-time LDPC encoder 606 and the imaginary-part space-time LDPC encoder 608 each encode their input information data according to the parity check matrix H stored in the memory 602 . The space-time LDPC codeword C 1 and the space-time LDPC codeword C Q output from the real-part space-time LDPC encoder 606 and the imaginary-part space-time LDPC encoder 608 are input to the first signal mapper 610 and the second signal mapper 612 , under the control of the controller 604 .
[0100] The first signal mapper 610 and the second signal mapper 612 each signal-map the space-time LDPC codeword C 1 and the space-time LDPC codeword C Q output from the real-part space-time LDPC encoder 606 and the imaginary-part space-time LDPC encoder 608 with any one of the QPSK and 4QAM schemes. The first signal mapper 610 transmits its signal-mapped signal over the air via the first transmission antenna, and the second signal mapper 612 transmits its signal-mapped signal over the air via the second transmission antenna.
[0101] FIG. 7 is a flowchart illustrating an operation of a receiver in a mobile communication system according to an embodiment of the present invention. Referring to FIG. 7 , in step 700 , the receiver receives signals transmitted by its corresponding transmitter via a plurality of reception antennas, for example, P, of first to P th reception antennas prepared therein. In step 702 , the receiver detects received signals based on the signals received via the first to P th reception antennas. There are various possible schemes for detecting the received signals, and it is assumed in FIG. 7 that the received signals are detected with the following scheme.
[0102] In step 704 , the receiver performs spatial mapping node decoding on the detected received signals. Here, the spatial mapping node decoding refers to an operation detecting a message transmitted from a spatial mapping node to a first LDPC decoder (not shown) and a second LDPC decoder (not shown) based on a message transmitted from a reception node to the spatial mapping node, a decoded output value for a first LDPC codeword, i.e., a decoded output value of the first LDPC decoder for decoding the first LDPC codeword, and a decoded output value for a second LDPC codeword, i.e., a decoded output value of the second LDPC decoder for decoding the second LDPC codeword. In step 706 , the receiver performs a decoding process on the first LDPC codeword, i.e., performs a first LDPC decoding process. In step 708 , the receiver performs a decoding process on the second LDPC codeword, i.e., performs a second LDPC decoding process. After steps 706 and 708 , the receiver proceeds to step 710 .
[0103] In step 710 , the receiver determines if a decoding stop condition is satisfied based on the results of the first LDPC decoding process and the second LDP decoding process. The decoding stop condition is given to determine if a predetermined iteration number has arrived or a decoding result up to now satisfies the parity check matrix H. That is, the receiver stops the decoding operation when the number of decoding processes exceeds the iteration number or the decoding result up to now satisfies the parity check matrix H.
[0104] If it is determined in step 710 that the decoding stop condition is satisfied, in step 712 , the receiver calculates a decoded value based on the decoding result up to now, i.e., the result value of the first LDPC decoding process and the result value of the second LDPC decoding process. In step 714 , the receiver performs hard decision on information data based on the calculated decoded value, and then ends all of the decoding processes.
[0105] However, if it is determined in step 710 that the decoding stop condition is not satisfied, the receiver returns to step 704 . That is, the receiver performs iterative decoding on the initially received signal, thereby improving its decoding performance.
[0106] FIG. 8 is a block diagram schematically illustrating a receiver in a mobile communication system according to an embodiment of the present invention. Referring to FIG. 8 , the receiver includes a plurality of reception antennas, for example, 2, of first and second reception antennas, a detector 800 , a spatial mapping node decoder 802 , a controller 804 , a memory 806 , a first LDPC decoder (LDPC decoder # 1 ) 808 , a second LDPC decoder (LDPC decoder # 2 ) 810 , and a hard decision unit 812 .
[0107] The first and second reception antennas each receive signals transmitted by a corresponding transmitter, and output the received signals to the detector 800 . The detector 800 detects transmission signals transmitted from first and second transmission antennas of the transmitter, from the received signals output from the first and second reception antennas, and outputs the detected signals to the spatial mapping node decoder 802 . The spatial mapping node decoder 802 receives the signal output from the detector 800 , spatial-demaps an estimation value detected by the detector 800 for the signals transmitted from the first transmission antenna and the second transmission antenna, and outputs the spatial demapping result to the first LDPC decoder 808 and the second LDPC decoder 810 . Although the signal input to the spatial mapping node decoder 802 includes only the signal output from the detector 800 at first, it later includes not only the signal output from the detector 800 , but also the signals output from the first LDPC decoder 808 and the second LDPC decoder 810 .
[0108] The first LDPC decoder 808 performs LDPC decoding on the signal output from the spatial mapping node decoder 802 with a decoding scheme corresponding to an encoding scheme used in a first LDPC encoder based on a parity check matrix designed in a space-time LDPC encoder of the transmitter. When the transmitter uses the QPSK scheme as a signal mapping scheme as described in connection with FIG. 6 , the first LDPC decoder 808 performs a decoding operation corresponding to an encoding operation of the real-part space-time LDPC encoder 606 . That is, the controller 804 controls the first LDPC decoder 808 to perform a decoding process according to a parity check matrix designed to obtain a full diversity gain, stored in the memory 806 .
[0109] Similarly, the second LDPC decoder 810 performs LDPC decoding on the signal output from the spatial mapping node decoder 802 with a decoding scheme corresponding to an encoding scheme used in a second LDPC encoder based on the parity check matrix designed in the space-time LDPC encoder of the transmitter. When the transmitter uses the QPSK scheme as a signal mapping scheme as described in connection with FIG. 6 , the second LDPC decoder 810 performs a decoding operation corresponding to an encoding operation of the imaginary-part space-time LDPC encoder 608 . That is, the controller 804 controls the second LDPC decoder 810 to perform a decoding process according to the parity check matrix designed to obtain a full diversity gain, stored in the memory 806 .
[0110] A detailed description will now be made of operations of the detector 800 and the spatial mapping node decoder 802 .
[0111] A transmission signal transmitted at a particular time t will be defined as a 2-element transmission signal vector x t , and a reception signal received at the particular time t will be defined as a 1-element reception signal vector y t . Because the transmission signal vector x t is transmitted via two transmission antennas of first and second transmission antennas, it includes two elements.
[0112] A channel that the transmission signal experiences is a fading channel, the fading channel will be expressed as a 1×2 matrix Ω t , and a noise component will be expressed as a 1-elemetn noise vector n t . Then, a relation of Equation (12) is given.
y t =Ω t x t +n t (12)
[0113] In Equation (12), the transmission signal vector x t can be expressed as x t =(x t 1 ,x t 2 ) considering the signals transmitted via the first and second transmission antennas at a time t. Here, x t 1 denotes a signal transmitted via the first transmission antenna at the time t, and x t 2 denotes a signal transmitted via the second transmission antenna at the time t. Therefore, for the transmission signal vector x t =(x t 1 ,x t 2 ), a probability vector P t for the reception signal vector y t can be expressed as shown in Equation (13). For convenience, it will be assumed herein that the signal mapping scheme used by the transmitter is the BPSK scheme, and the QPSK scheme rather than the BPSK scheme can also be used as the signal mapping scheme.
P t =( P t ( x t 1 =1 ,x t 2 =1), P t ( x t 1 =−1 ,x t 2 =−1), P t ( x t 1 =1 ,x t 2 =−1), P t ( x t 1 =−1 ,x t 2 =−1)) (13)
[0114] As shown in Equation (13), for the transmission signal vector x t =(x t 1 ,x t 2 ), the probability vector P t for the reception signal vector y t includes 4 elements. Because the transmitter uses the BPSK scheme as its signal mapping scheme, the probability vector P t includes 4 elements. As a result, the reception signal vector y t becomes a message detected for the detector 800 .
[0115] When x t =(x t 1 ,x t 2 )=(i,j),(i,jε−1,1), each of the 4 elements of the probability vector Pt can be calculated by Equation (14).
P t ( x t 1 =i, x t 2 =j )= Pr ( x t 1 =i, x t 2 =j|y t ) (14)
[0116] In Equation (14), Pr denotes an operator for calculating probability. As described above, the detector 800 detects the probability vector P t , and outputs the detected probability vector P t to the spatial mapping node decoder 802 .
[0117] A log likelihood ratio (LLR) message output from the spatial mapping node decoder 802 to the first LDPC decoder 808 , transmitted from the first transmission antenna, can be expressed as shown Equation (15).
L t 1 = log Pr ( x t 1 = + 1 ❘ y t ) Pr ( x j t = - 1 ❘ y t ) = log ∑ x t 2 ∈ { - 1 , 1 } Pr ( x t 1 = + 1 , x t 2 ❘ y t ) Pr ( x t 2 ❘ y t ) ∑ x t 2 ∈ { - 1 , 1 } Pr ( x j t = - 1 , x t 2 ❘ y t ) Pr ( x t 2 ❘ y t ) ( 15 )
[0118] In Equation (15), Pr(x k 2 |y k ) can be detected from the output values of the first LDPC decoder 808 and the second LDPC decoder 810 . Also, an LLR message transmitted from the second transmission antenna can be detected in the same method as the method for detecting the LLR message transmitted from the first transmission antenna. The LLR message transmitted from the second transmission antenna is input to the second LDPC decoder 810 .
[0119] Above, a description has been made of operations of the detector 800 and the spatial mapping node decoder 802 when the transmitter uses the BPSK scheme as its signal mapping scheme. Next, a description will be made of operations of the detector 800 and the spatial mapping node decoder 802 when the transmitter uses the QPSK scheme as its signal mapping scheme.
[0120] For a transmission signal vector x t =((x t 1 ) I ,(x t 1 ) Q ,(x t 2 ) I ,(x t 2 ) Q ) transmitted by the transmitter, a probability vector P t for a reception signal vector y t received at the receiver can be expressed as shown in Equation (16).
P t =( P t (( x t 1 ) I =1,( x t 1 ) Q =1,( x t 2 ) I =1,( x t 2 ) Q =1 , . . . , P t ( x t 1 ) I =−1,( x t 1 ) Q =−1,( x t 2 ) I =−1,( x t 2 ) Q =−1)) (16)
[0121] As shown in Equation (16), for the transmission signal vector x t =((x t 1 ) I ,(x t 1 ) Q ,(x t 2 ) I ,(x t 2 ) Q ), the probability vector P t for the reception signal vector y t includes 16 elements. Because the transmitter uses the QPSK scheme as its signal mapping scheme, the probability vector P t includes 16 elements. As a result, the reception signal vector y t becomes a message detected for the detector 800 .
[0122] When x t =((x t 1 ) I ,(x t 1 ) Q ,(x t 2 ) I ,(x t 2 ) Q )=(i,j,k,l),(i,j,k,lε−1,1), each of the 16 elements of the probability vector P t can be calculated by Equation (17).
P t (( x t 1 ) I =i ,( x t 1 ) Q =j ,( x t 2 ) I =j ,( x t 2 ) Q =1)= Pr (( x t 1 ) I =i ,( x t 1 ) Q =j ,( x t 2 ) I =k ,( x t 2 ) Q =1 |y t ) (17)
[0123] As described above, the detector 800 detects the probability vector P t , and outputs the detected probability vector P t to the spatial mapping node decoder 802 . A real-part LLR message output from the spatial mapping node decoder 802 to the first LDPC decoder 808 , transmitted from the first transmission antenna, can be expressed as shown in Equation (18).
( L t 1 ) I = log Pr ( ( x t 1 ) I = + 1 ❘ y t ) Pr ( ( x t 1 ) I = - 1 ❘ y t ) = log ∑ ( x t 1 ) Q , ( x t 2 ) I , ( x t 2 ) Q ∈ { - 1 , 1 } Pr ( ( x t 1 ) I = + 1 , ( x t 1 ) Q ( x t 2 ) I , ( x t 2 ) Q ❘ y t ) Pr ( ( x t 1 ) Q ( x t 2 ) I , ( x t 2 ) Q ❘ y t ) ∑ ( x t 1 ) Q , ( x t 2 ) I , ( x t 2 ) Q ∈ { - 1 , 1 } Pr ( ( x t 1 ) I = - 1 , ( x t 1 ) Q ( x t 2 ) I , ( x t 2 ) Q ❘ y t ) Pr ( ( x t 1 ) Q ( x t 2 ) I , ( x t 2 ) Q ❘ y t ) ( 18 )
[0124] In Equation (18), Pr((x t 1 ) Q , (x t 2 ) I , (x t 2 ) Q |y k ) can be detected from the output values of the first LDPC decoder 808 and the second LDPC decoder 810 . Also, an imaginary-part LLR message transmitted from the first transmission antenna, a real-part LLR message transmitted from the second transmission antenna and an imaginary-part LLR message transmitted from the second transmission antenna can be detected in the same method as the method for detecting the real-part LLR message transmitted from the first transmission antenna. The LLR message transmitted from the second transmission antenna is input to the second LDPC decoder 810 .
[0125] The first LDPC decoder 808 and the second LDPC decoder 810 decode a first LDPC codeword and a second LDPC codeword based on the output value of the spatial mapping node decoder 802 , and the decoded signals are input back to the partial mapping node decoder 802 and the hard decision unit 812 , thereby increasing reliability of initially estimated signals. The hard decision unit 812 performs a hard decision on the signals output from the first LDPC decoder 808 and the second LDPC decoder 810 , finally restoring the signals into information data.
[0126] As described above, the present invention newly proposes a parity check matrix capable of encoding and decoding a space-time LDPC code having a full diversity gain, thereby maximizing error correction capability and entire system performance. In addition, because the LDPC scheme is used as a coding scheme of a space-time code, it is possible to encode and decode the space-time code to improve performance with a relatively simple hardware structure.
[0127] While the present invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims. | In a mobile communication system including a transmitter and a receiver, an LDPC code is generated by encoding received information data such that a fifth partial matrix obtained by combining a second partial matrix having even-numbered columns of a first partial matrix corresponding to the information data with a fourth partial matrix having odd-numbered columns of a third partial matrix corresponding to a parity, and an eighth partial matrix obtained by combining a sixth partial matrix having odd-numbered columns of the first partial matrix with a seventh partial matrix having even-numbered columns of the third partial matrix correspond to a ninth partial matrix obtained by exclusive-ORing the first partial matrix and the third partial matrix and a parity check matrix having a predetermined rank in a binary field. A space-time LDPC code is generated by spatial-mapping the LDPC code according to a predetermined spatial mapping scheme. | 7 |
FIELD OF THE INVENTION
[0001] During the manufacture of paper, a web of paper fibers derived from wood sources and also from recycled paper sources is typically formed on the surface of a fabric mesh which is used to drain excess water from the web. The drained web of fibers is then introduced into a series of rolls, some of which are covered by continuous belts of fabric or felt. As the paper web is fed through the rolls and between the layers of felt, pressure is applied to the paper web which forces water from the web.
[0002] The fabrics are composed of various types of polyester or polyamide filaments of varying diameters or denier. The fabrics may be woven together into a mesh or needled into a mesh base to form a batt. It is highly desirable that these fabrics remain clean during their service lives. A clean fabric will facilitate proper drainage of water from the paper web. Proper drainage of water from the paper web will allow the paper web to attain optimum strength and allow it to be dried more easily in subsequent paper manufacturing operations. Improved paper strength results in fewer paper breaks, allowing for uninterrupted machine operation and is a desired characteristic of the final paper product.
[0003] The paper fiber web, which is carried by the forming fabric and press fabrics, often contains undesirable contaminants. These include materials that may come from recycled fiber sources and include: inks, resins, hot melt and pressure sensitive adhesives, styrene butadiene, polystyrene, vinyl acrylates, rubber, waxes, and polyethylene. These materials are commonly known as stickies. Contaminants may also come from natural fiber sources and include: fatty acids salts and their esters, and abietic acid salts and their esters. These materials are commonly known as pitch. Finally, some contaminants are introduced during processing and include: wet strength resins, latexes, vinyl acrylates and paper sizing agents. These contaminants are also known as white pitch. These materials may contaminate the fabrics used to carry the paper web. They may coat the fabrics, impeding drainage and uniform paper formation, or they may completely obstruct the fabric in certain areas causing the appearance of light spots or holes in the paper web which greatly detract from the aesthetic and functional properties of the paper as well as causing the paper to break more easily from that point onward.
[0004] Typically, these contaminants are removed after deposition. Cleaning chemicals and solvents are often used, either continuously or intermittently during the production of paper, or when the papermaking equipment is not in production. These materials have varying degrees of success depending on the nature of the contaminant and the cleaning method employed. In many cases, powerful solvents and caustic materials are needed to remove the contaminants. These negatively impact paper mill wastewater treatment facilities, as well as requiring more stringent occupational health and safety precautions.
[0005] Applying cationic polymers to the surface of papermaking fabrics prevents the accumulation of deposits. Further, anionic surfactants as well as cationic polymers may be separately applied to a papermaking fiber slurry or directly to papermaking surfaces to prevent contamination, as described in Driesbach U.S. Pat. No. 5,556,510. This patent does not disclose the method for making a stable product from a combination of cationic polymer and anionic surfactant, the residual charge on the cationic polymer or the nature of the hydrophilic moieties on the anionic surfactant. In addition, it has been postulated that when cationic polymers alone are applied to a papermaking surface that the cationic polymers adsorb onto the papermaking surface and also attract anionic surfactants from the aqueous component of the fiber slurry or paper web (D. T. Nguyen, TAPPI June 1998). These methods also present problems. Applying an anionic surfactant along with a cationic polymer, as described by Driesbach, presents stability problems. These materials are typically incompatible and will not form a stable mixture. This makes the application of this mixture difficult when applied as either a single product or when the cationic polymer and anionic surfactant are applied separately.
[0006] When only a cationic polymer is applied to a papermaking fabric the efficacy of the polymer is dependent on the nature of the anionic species in the papermaking furnish. This furnish will vary and may diminish the effectiveness of the polymer. According to generally accepted theories, the cationic polymer should nave some cationic nature to ensure that it is suitably attracted to the anionic surface of a papermaking fabric.
[0007] Hence, it would be beneficial for ease of application to have a stable product with a balanced cationic charge that could be applied to a papermaking surface, which would incorporate both a cationic polymer and anionic surfactant with the specific properties needed to impart optimum contaminant resistant properties to the papermaking fabric.
SUMMARY OF THE INVENTION
[0008] The present invention is premised on the realization that cationic polymer and anionic surfactants interact to form a hydrophilic layer on a negatively charged surface such as that found in papermaking. By applying such a product to a papermaking surface such as a felt or forming fabric, it is possible to impart a deposition resistance to that surface. This deposition resistance may be achieved by continuously coating the surface of the fabric with a liquid mixture including a cationic polymer, a non-ionic surfactant and an anionic surfactant. The amount of the anionic surfactant relative to the cationic polymer is such that the cationic polymer retains a substantial portion of its positive charge, generally 1.0%-50%.
[0009] More preferably, the cationic polymer is a polydiallyldimethylammonium chloride and the anionic surfactant is a carboxylated linear alcohol, although a wide variety of other polymers and surfactants can be employed. The ability to apply a single stable product with specially selected anionic surfactants is a benefit in terms of ease of application and uniformity of the anionic surfactants which are complexed by the cationic polymer. Without limiting the generality of this invention, it has been discovered that anionic surfactants which contain a hydrophilic portion and, more specifically, a portion of the molecule which consists of ethylene oxide monomer adducts, is particularly well suited for the purposes of the invention. Alternatively, a sulfo oxo moiety may be used in the surfactant to achieve similar results.
[0010] The invention will be further appreciated in light of the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The FIGURE is a diagrammatic of a papermaking process.
DETAILED DESCRIPTION
[0012] The present invention is a method of improving the deposition resistance of papermaking fabric. This is accomplished by applying the composition of the present invention directly to the papermaking fabric by spraying or with applicator rolls. The composition of the present invention comprises a cationic polymer in combination with a non-ionic surfactant and an anionic surfactant.
[0013] A wide of variety of cationic polymers can be used in the present invention. In general, these cationic polymers must be water soluble and are formed from cationic monomer units or both cationic and non-ionic monomer units. By the term cationic, it is meant that the monomer unit includes a group that either carries a positive charge or that has basic properties and can be protonated under mild acidic conditions.
[0014] Suitable polymers include cationic addition and condensation polymers. The polymer will generally be composed partially of vinyl addition polymers of cationic and optionally non-ionic vinyl monomers.
[0015] One preferred class is the quaternary ammonium polymers. These quaternary ammonium polymers are generally derived from ethylenically unsaturated monomers containing a quaternary ammonium group or obtained by reaction between an epihalohydrin and one or more amines such as those obtained by reaction between a polyalkylene polyamine and epichlorohydrin or by reaction between epichlorohydrin, dimethyl amine and either ethylenediamine or polyalkylene polyamine.
[0016] Cationic polymers are disclosed in U.S. Pat. No. 5,368,694 the disclosure of which is incorporated herein by reference. Generally, with all these, the molecular weight must be such that the polymer is water soluble or dispersible.
[0017] Other suitable cationic polymers include cationized polyacrylamides including polyacrylamides cationized with dimethylsulfate or methyl chloride by the Mannich reactions to varying degrees to achieve varying degrees of cationicity, polymers derived from quaternized dimethyl aminoethylacrylate, dicyanamide-formaldehyde condensates using one or both of formic acid and ammonium chloride as reactants, cationic cellulose starch compounds, carboxylated starch, xanthan gum, guar gum and polyacrylic acid. One preferred cationic polymer is polydiallyldimethylammonium chloride.
[0018] A wide variety of non-ionic surfactants can be used in the present invention. These include ethoxylated fatty alcohols which are either linear or branched and which may have a carbon chain length of anywhere from 8 to 22 carbons. The degree of ethoxylation may vary from 3 moles to 22 moles of ethylene oxide per mole of alcohol. These would include the Rexonic® and Neodol® line of linear alcohol ethoxylates. Ethoxylated adducts of alkyl phenols as well as ethoxylated polyhydric alcohols including sorbitols or sorbitan esters may be used. Additional non-ionic surfactants include polyethylene oxide/polypropylene oxide block copolymers which would include the Pluronic® line of surfactants as well as ethoxylated versions of fatty acids and polyethylene glycol esters of phosphates, polyethylene glycol esters of fatty acids including esters derived from one mole of polyethylene glycol and one or two moles of fatty acids, tristyrylphenol ethoxylates and alkylpolyglycosides.
[0019] Generally the HLB of these surfactants will be from 7 to 18 with a preferred range being from about 11 to 13. Preferred nonionics include Rexonic® N23-6.5 and Neodol™ N23-6.5.
[0020] The third component of the present invention is an anionic surfactant. Suitable anionic surfactants include water soluble or water dispersible alkylarylsulfonates, sulfonated amines and amides, carboxylated alcohol ethoxylates, diphenylsulfonate derivatives, lignin and lignin derivatives, phosphate esters, soaps of process rosin, sulfates and sulfonates of ethoxylated alkyl phenols, sulfates of ethoxylated alcohol, sulfonates of napthalene and alkylnapthalene, polyethoxy carboxylic acid alcohols from the Neodox™ or Sandopan™ line of products, alky ether sulfates, alkyl benzene sulfonates, alkyl sulfonates, alkyl phosphates, alkyl sulfates, alpha olefin sulfonates, diphenyloxide disulfonates sulfosucinnates, ethoxylated sulfosucinnates and succinamates. One preferred surfactant of the present invention is a carboxylic acid capped ethoxylated tridecyl alcohol. A surfactant which incorporates a polyoxytheylene component in addition to an anionic component is particularly suited for this invention in that it allows a stable product to be more easily formulated as well as conferring a hydrophillic property to the papermaking surfaces on which it is applied in conjunction with a cationic polymer.
[0021] Preferably, the composition comprises polydiallyidimethylammonium chloride in combination with trideceth (7) carboxylic acid and linear alcohol ethoxylate such as Rexonic® N23-6.5 or Neodol® N23-6.5. Alternatively, a secondary alkane sulfonate sodium salt based on n-paraffin sodium (C14-C16 Alkyl Sec Sulfonate) such as Hostapur SAS 60 may be used as the anionic surfactant.
[0022] The amount of anionic surfactant to cationic polymer should be established so that the cationic polymer retains a significant portion of its cationic charge. Generally from 10%-80% of its positive charge should be maintained after the addition of the anionic surfactant.
[0023] With only the above three components, the composition will be very acidic. The pH of the composition can be raised by the addition of water soluble bases such as sodium or potassium hydroxide, sodium or potassium carbonate, ammonia, organic amines such as triethanolamine, diethanolamine, monoethanolamine, or morpholine as well as other compatible bases. Sufficient base can be added to establish a desired pH of from about 3 up to about 10 depending on preference for the particular papermaking operation.
[0024] The composition of the present invention will generally include 2% to 20% by weight cationic polymer, 2% to 40% by weight nonionic surfactant, 0.5% to 10% anionic surfactant 0% to 5% base with the remainder water.
One preferred formulation is as follows: Agefloc WT 40HB (40% active) 5% Rexonic N23-6.5 (100% active) 7.4% Sandopan DTC Acid (90% active) or 1.1% Hostapur SAS 60 (60% active)
with the remainder water. This is further diluted to obtain the desired application or use concentration. Generally, the use concentration will be 2-10,000 ppm (actives) and, preferably, 30 to 100 ppm actives.
[0025] The FIGURE is a diagrammatic depiction of a press felt system for use in the present invention. The press felt system 10 includes an upper press felt run 12 . As shown in the drawing, the paper travels in the direction of arrow 14 .
[0026] Low pressure fan shower 16 and high pressure needle showers 18 apply the treatment agent of the present invention to the return runs 22 of the upper and lower press felt runs. Alternately, coating rollers can be employed. This, of course, is a diagrammatic depiction of a press felt run and is intended merely for use in explaining the present invention.
[0027] The present invention will be further appreciated in light of the following detailed example.
EXAMPLE 1
[0000] Mill Type: Linerboard
[0000] Furnish: 100% OCC
[0000] Application Location: Bottom of former before the first sheet side return roll.
[0028] Problem: Stickies would accumulate on the forming fabric usually within 6-24 hours of having been cleaned. These stickies originated from the old corrugated cardboard furnish that was being used. These stickies manifested themselves as large diameter “patches” on the surface of the wire, severely impeding the drainage of the paper slurry on the forming fabric and decreasing sheet quality. The only way to clean them was through the use of an aliphatic solvent cleaner. Other methods which had been tried as traditional passivation chemistry using cationic polymers alone or traditional cleaners either did not work or caused the deposition to occur in other places on the machine. The cost of the program was becoming prohibitive and required an excessive amount of solvent.
[0029] The above preferred formulation was applied to a shower just slightly ahead of where the solvent was being applied at the rate of 100 ml/min and optimized to 60 ml/min. The deposition problem diminished dramatically in an unexpected way such that the solvent cleaning frequency has been reduced to only once per week rather than 2-3 times per day. This has resulted in a solvent use reduction of 90% and a cost reduction of approximately 10%.
[0030] This method is a radical departure from the typical solvent cleaning methods previously used to deal with pitch and stickies. Instead of dissolving the pitch and stickies, this method prevents deposition. This, in turn, reduces the use of solvents, which is desirable in itself. It also reduces cost and improves efficiency.
[0031] This has been a description of the present invention along with the preferred method of practicing the present invention. However, the invention itself should be defined by the appended claims WHEREIN | Pitch and sticky accumulation on papermaking fabric is reduced by applying a solution or dispersion of a cationic composition to the fabric. The cationic composition includes a cationic polymer, a nonionic surfactant and an anionic surfactant and retains a net cationic charge. Preferably, this is continuously applied during the papermaking process. | 3 |
[0001] This patent application is a continuation-in part of mainly PCT application PCT/IL 01/00981 which was filed in Israel on Oct. 24, 2001, which claims priority from Israeli patent application 139234 of Oct. 24, 2000 and from US provisional patent application 60/266,732 of Feb. 5, 2001.
[0002] This patent application is also a continuation-in part of PCT application PCT/IL 01/00330 which was filed in Israel on Apr. 9, 2001, which claims priority from Israeli patent application 135556 of Apr. 9, 2000 and from Israeli patent application 139234 of Oct. 24, 2000 and from US provisional patent application 60/266,732 of Feb. 5, 2001.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to cellular phones, and more specifically to a system and method for exposing the user's brain to much less microwave radiation than ordinary cellular phones with the help of a proxy device.
[0005] 2. Background
[0006] Mobile or cellular telephones are becoming more common and popular amongst all sectors of the population for business and private conversations, including many children. There are hundreds of millions of users around the world already, and more than 300,000 new users are joining each day. For example in Britain, cellular phones have become the most popular gift for children and there are now more than 500,000 children in Britain alone who are using cellular phones. There is much concern that the microwave emissions from the cellular antenna that is held close to user's head may have deleterious effects on the user, such as tumors, Altzheimer, and other medical and psychological problems. For example, just on October 1999, Dr. George Carlo, head of the Cellular Research Institute in Washington came up with frightening results: He found that the usage of cellular phones increases the chance for brain tumors and also may cause genetic damage. Altogether, since 1997, more and more research has increased the suspicions that the electromagnetic emissions of cellular phones to the brain are dangerous. Already in December 1996 an article published in LA Times showed suspicions that it might cause also Altzheimer disease. In Scandinavia in recent years there have been even more warnings about these possible dangers. Also, many people are complaining about headaches after using cellular phones. Recent studies, such as described in an article by Allan Frey in Environmental Health Perspectives of March 1988, and in Dr. George Carlo's book, Cell Phones: Invisible hazards in the wireless age, published in 2001, have shown that even short time exposure to microwave radiation at the level and frequencies typical of cellular phone quickly causes a breakdown of the Blood-Brain-Barrier, which protects the brain from carcinogens and other toxins in the blood stream, and this is suspect of being the main mechanism that might cause both cancer and the headaches.
[0007] Many have searched for methods for protecting the cellular phone users from this radiation. One of the most common ways to try to avoid these problems until recently has been the usage of headsets—personal earphones with microphone. On Apr. 4, 2000 it was published worldwide that a research conducted by the “Which?” consumer Magazine in Britain found that unfortunately instead of protecting the users of cellular phones from the electromagnetic radiation (and especially the microwave radiation), in fact the earphone and its cable can act as an Antenna and expose the user to up to even 3 times more dangerous radiation than when using the cellular phone directly without the external earphone. Furthermore, this emission goes directly to the brain. This finding is extremely shocking and intolerable since so many people have been buying these earphones because of publications that they prevent or reduce the exposure to the radiation of the cellular phones. In addition to this, the report of the independent expert committee on cellular phones hired by the British government, published on May 11, 2000, estimated that children are even more vulnerable to the effects of the cellular phone radiation than adults.
[0008] In addition to this, according to an article in the Israeli newspaper Maariv from Aug. 4, 2000, a medical doctor from Baltimore just sued a number of cellular companies for 800 million dollars, claiming that it caused him brain tumor. He also appeared on TV and called to the public to stop using cellular phones and not to give them to children. Also, according to the Baltimore Sun of Jan. 17, 2001, Peter Angelos recently joined the $800 million lawsuit by the Baltimore neurologist, and plans to file additional class-suits against members of the US mobile phone industry. These latest developments will probably also cause the cellular companies to be much more willing to adopt safer solutions.
[0009] One possible solution is using a special headset (with at least 1 earphone and microphone) where the cable is based on non-metallic conductors, such as sound conductors (e.g. a hollow air tube) or optic fiber(s), as described in a separate patent application by the present inventor.
[0010] Another possible solution, offered recently by Erikson and a few additional companies, is to use a headset based on bluetooth technology. Bluetooth technology can broadcast only to a small distance (typically up to about 10 meters), and therefore, although it also uses microwave radiation, its levels are much lower than cellular phones—between 1-10 milliwatts, compared to up to 2 watts in cellular phones, so the levels of radiation should be 100-1000 times lower. An additional advantage is that the cellular phone itself can be even in your suitcase or bag while answering calls through the headset. On the other hand, if you want to initiate a call in this way while the phone is not in your hands (especially when it is in your bag or suitcase), you need to use voice commands for dialing, which is what Erikson offers, eventhough probably cheaper versions will be available without this additional option. Bluetooth technology also has a built-in automatic encryption and decryption and a built-in ability to automatically jump between many channels of different frequency (typically at least 80 channels) in order to avoid conflict and interference with other nearby bluetooth devices. This is supposed to be the new state of the art for cellular headsets in about 2 years from now.
SUMMARY OF THE INVENTION
[0011] The present invention is a reverse and a more sophisticated solution that complements the above described bluetooth headset solution. Since many people don't like using headsets at all because they feel they are less convenient and because many cheap headsets use earphones and microphones of poor hearing quality (compared to the level of the built-in microphone and speaker in the phone itself), the present solution solves the problem also for all those people that prefer to use the phone directly without the earphones.
[0012] More specifically, the level of microwave radiation to which the user is exposed near his brain is reduced by a large factor by enabling the phone to communicate with a very near proxy device by using low levels of radiation to communicate wirelessly with the proxy device or using an alternative method with no metallic wire and no radiation to communicate with the proxy device. This can be done in a number of preferable ways:
[0013] 1. The cellular phone is redesigned so that instead of using an ordinary cellular phone antenna it can use preferably a bluetooth chip or any other device for short range low energy wireless communication, and instead of communicating with the cellular company's nearest cell or cells (as a normal cellular phone would do), it can communicate with a proxy device, which is a transducer that on one hand transfers information from and to the cellular phone through another bluetooth chip or similar device, and on the other hand communicates preferably through a normal cellular antenna with the cellular company's nearest cell(s) instead of the cellular phone. Also, preferably, the recharger unit of the cellular phone is redesigned so that it has two sockets, one for the cellular phone and one for the proxy, and so both can be recharged at the same time, or for example the cellular phone or the proxy can have a separate recharge socket of their own, so that the two devices can be connected to the recharger in serial mode instead of in parallel. Another possible variation is that preferably, the phone has also its normal antenna and its related circuits, and preferably is able to sense if there is any temporary problem with the proxy device and if for some reason the proxy device cannot be reached or does not function, the phone can then preferably temporarily revert to normal operation and communicate with the cellular company's nearest cells normally. In such a case, preferably a sound and/or light will flash, alerting the user that he is again exposed to the microwave radiation. Preferably, in this case, the warning sound will keep repeating every few seconds, thus reminding the user all the time that he is currently using the phone in potentially unsafe mode. Preferably, the cellular phone and the proxy set both have a matching private encryption key, and will refuse to communicate with a pair that does not fit. Preferably, this private encryption key can be easily added or changed, for example by use of EPROM, in each of the two members of the pair (the phone or the proxy) in case the other member (the phone or the proxy) was lost or damaged. The use of the proxy will be OK also when the cellular phone is used for data communication (instead of voice communication), such as Internet access, because the bluetooth and similar technologies can transfer at least 1 Megabit per second and will probably improve further in the future. Another possible variation is that, when using the cellular phone for data communication, since the phone is typically in the user's hand and away from his head, the user might be given the choice also on purpose to work without the proxy and temporarily disable the warning. However, this is not recommended, since for viewing the cellular phone's screen the cellular phone might still be held relatively close to the user's head. Another possible variation of this solution is that the phone does not have a normal cellular antenna and its circuitry and always relies on the proxy to communicate with the cellular company's cells, and preferably is based on maximum energy saving and therefore preferably also has a smaller rechargeable battery and/or can work longer before recharging is needed, so that it is preferably considerably lighter than a normal cellular phone. This can be accomplished for example by using CMOS circuits as much as possible and PWM (Pulse width Modulation) and also for example a Piezoelectric speaker or for example a speaker based on a small air-tube that goes into the ear like in hearing aids for the deaf, which saves energy, etc. (However, such an invasive device would be of course less desirable). If PWM is used, it can be used for example while communicating between the phone and the proxy, or the communication can be any other communication such as for example the standard Bluetooth protocol, and in that case the PWM can be used for example inside the phone itself to transfer the information in an energy-efficient manner to the speaker. An additional preferable way of saving energy is for example to automatically reduce the duty cycle of the transmitter (or stop it completely) when the user is not talking, and when he starts to talk it is quickly restarted. This might cause a few milliseconds of speech at the start of a new speech to become lost, but that is negligible. In some embodiments these energy-efficiency principles can be used also with the other solutions and especially for example solution number 2, so that when the phone is held near the user's head and communicates with the proxy it works in the energy efficient mode, and for example when the proxy is used as headset it also consumes as little energy as possible, thus preferably extending time until recharge is needed. If such methods of energy saving are applied for example to bluetooth or other short range low energy wireless headsets, then the battery can be either a single-use battery, preferably one that can last a long period such as for example a few months (for example with up to 3 hours talk-time per day) with the efficient circuit, or a rechargeable battery that preferably can also last relatively long with the efficient circuit until recharge is needed. This is considerably better than the state of the art of having to recharge after at most a few hours of talk. However, since for example in current day bluetooth chips typically most of the energy is used by the RISC processor, it might be difficult to considerably save energy this way, whereas other methods such as for example UWB or other pulse based carrier-free technologies can be much more energy efficient. Preferably, the phone can also fold open into a shape of a headset or have part of it extended and be conveniently hung on the ear or on the head, preferably with an appropriate band or hook, and so the phone itself can function dually both as a hand-held phone and as a hands-free headset device, which is also very useful for example when driving, so that the driver does not need to dial first with the phone and then look for the headset and insert it, as is typically done in the present state of the art normal type of earphones. Preferably, the phone is made even lighter by making it for example thinner, and possibly also somewhat smaller. This variation has the advantage (compared to solution number 2) that only one (preferably high quality) speaker and earphone are needed in the system and only one cellular antenna and it's circuitry and it's required battery are needed in the system. In this variation, if the phone is used also for Internet access, then preferably the proxy itself has also a display screen, which is preferably bigger than the phone's display screen, and preferably also a convenient keyboard, so that the user can either hold the phone in his hand for Internet access, or use it as headset and hold the proxy in the hand for viewing the screen and keying commands. Another possible variation is that the phone fits over the proxy like a phone cover, like a two-part phone, so when the user opens the phone to initiate or answer a call it feels like picking up the phone's cover. In this case preferably the phone is recharged from a recharge socket on the proxy itself, which is most natural in this case and gives the user a feeling of normally recharging the phone, while actually he is recharging both the phone and the proxy. Another possible variation is for example the opposite, so that the proxy is recharged through the phone. This type of two-part phone configuration could be used also for example with normal Bluetooth or UWB headsets or other wireless headsets or for example optic fiber headsets, so that when the user picks up the phone's cover he is actually picking up the headset. Another possible variation is that preferably the proxy contains preferably just the transducer, and preferably only the phone contains the screen and the phone can be used preferably either for talking or for sliding the Internet or both at the same time, and in addition the phone can be used for example with a normal hands-free earphone or with a wireless earphone. If used with a wireless earphone then the phone can for example communicate with both the earphone and the proxy by bluetooth or similar device. Another possible variation is to add to the cellular phone and/or to the proxy for example volume control and/or pitch control, which are currently unavailable in cellular phones and in cellular earphones, in order to improve further the sound quality for example when it is difficult to hear. This can be used for example in solution 1 or in solution 2 , and also for example with any cellular phone or headset independently of any other features of this invention. Another possible variation which can be used with this and/or with any of the other solutions is that the phone and/or the proxy can be used to signal to the other device to emit a sound so that the user can find it if he misplaced it and has in his hand just one of the two devices. This feature can be used also independently of any other feature of this invention and also used for example with normal wireless or bluetooth or similar device headsets. Of course, various combinations of the above and additional variations can also be used.
[0014] 2. Same as solution 1, except that the phone has also the cellular antenna and its related circuits and the proxy device is preferably shaped like a headset (preferably at least in one of its states, such as for example when unfolded) and has also a preferably high-level microphone and earphone and can also function dually—in this case as either a proxy device, or as a headset. In this solution the proxy is preferably light in weight. When the user opens the phone and uses it normally, the proxy device preferably functions as described in solution number 1 (At least regarding some of the variations described in solution 1). On the other hand, if the user wants to put away the cellular phone and use a headset, he can use the proxy device as a headset and then the proxy device preferably disables its cellular antenna and the communication with the cellular company's cells and activate its speaker and earphone, and the cellular phone preferably deactivates it's own speaker and earphone and reactivate it's normal cellular antenna and related circuitry and communicates with the cellular company's nearest cells. By this sophisticated way the user can always have very low radiation levels both if he uses the phone directly and if he uses the proxy as headset. Another possible variation is that preferably, since the proxy device has already also the normal antenna and its related circuits, it also is able to sense if there is any temporary problem with the cellular phone, and if for some reason the cellular phone cannot be reached or does not function, the headset can then temporarily communicate directly with the cellular company's nearest cells. In such a case, preferably it will for example indicates a sound from its earphone, alerting the user that he is again exposed to the microwave radiation, and preferably keep repeating this sound every few seconds, reminding the user all the time that he is currently using the headset in potentially unsafe mode. In this solution, preferably both the proxy and the cellular phone can also talk to other bluetooth or similar devices in the home or in the office, so for example they can automatically (or for example by changing a switch or pressing some key(s)) communicate with the computer or with the regular phone base, when they also have a bluetooth chip or similar device. Since the rechargeable batteries required for the communication with the cellular company's cells might make the proxy device heavier, which makes it less convenient to use as an earphone, preferably the proxy uses lighter batteries, such as for example the new patented Hydrogen based batteries from Nec, which also have a much faster recharge time than ordinary batteries, and also preferably uses more energy efficient speaker and earphone. Another possible variation is that the proxy is composed of two easily detouchable parts, so that preferably one part contains the heavier battery needed for cellular communications and the cellular antenna and its circuitry, and the other part contains at least the earphone and microphone and a lighter battery, and preferably when the parts are physically coupled they are electrically connected, and when the user wants to use the proxy as headset he can remove and use just the needed part. Of course, various combinations of the above and additional variations can also be used.
[0015] 3. The cellular phone itself does not have to be changed and the two bluetooth chips or similar devices are not necessary, and instead the proxy is capitalizing on the cellular phone's ability to lower its radiation level automatically depending on the distance to the nearest cell. In this solution the proxy preferably imitates the cell by making the phone believe that it is talking to a very close cell, and on the other hand it communicates with the cellular company's cell, as in solution 1. The ability to implement solution number 3 might depend on the cellular communication protocol with the cell and on the extent and range by which the cellular phone is able to lower its radiation levels for very close cells. This solution can be useful for dealing for example with some currently existing cellular phones. However, cellular phones can be optimized to take more advantage of this, so that if for example a normal cellular phone might not go below a certain energy level in any case (because with normal cells for example a certain minimal distance might be assumed), a cellular phone can be designed so that it can reduce the energy level of the normal antenna to the very low levels needed to communicate for example with a proxy device that is just a few meters or less away. Preferably for example when a few users are close to each other the proxies and/or the phones (for example if the phone is redesigned for this) can use preferably automatic frequency hoping and/or encryption like in Bluetooth, in order to help privacy and/or avoid disturbances between the devices. Also, if the phone is redesigned, preferably it is also able to indicate to the user for example by a flashing sound or light if the proxy device cannot be reached or is malfunctioning, so that the user knows that he might now be exposed to the normal cellular radiation.
[0016] 4. Solution number 4 is similar to solution number 1, except that the proxy device is preferably physically coupled to the cellular phone at any convenient position or angle and extends the position of the cellular antenna away from the user's head as far as conveniently possible, preferably on a non-metallic rod, such as plastic. Preferably, this angle can be changed by the user in various directions, preferably by using a ball-type hinge. So, for example, the proxy can position the cellular antenna upwards away from the head, or downwards, at the opposite direction than usual, as far from the brain as conveniently possible. Preferably, this rod can be easily made longer or shorter by the user (preferably by telescopic design, or for example by being divided into several parts with one or more hinges between each two parts, so that it can be folded and unfolded in various ways). However, in this solution the cellular antenna's distance from the brain might be smaller than in the other solutions, so the reduction of the level of radiation that the user's brain is exposed to might be smaller than in the other solutions. Preferably, the proxy can be also easily removed from its position on the phone and can also be used further away from the user's head, as in solution 1. Preferably, for recharging, the proxy can either be removed from its position on the phone and moved to the appropriate socket, or for example an auxiliary wire can be used that is removed when not recharging.
[0017] 5. Solution number 5 is the same as solution number 1, except that instead of the bluetooth or other short range wireless device it uses optic fiber or fibers for the communication between the cellular phone and the proxy device. Preferably, the optic fiber can be easily and modularly replaced if damaged. One of the possible variations in this case and/or for example with solution no. 6 is to use for example in any of the connected devices a passive reflective microphone that works for example by a membrane that reflects a light beam back through one or more optic fibers, in order to save energy.
[0018] 6. Solution number 6 is the same as solution number 2, except that instead of the bluetooth or other short range wireless device it uses optic fiber or fibers for the communication between the cellular phone and the proxy device. Preferably, the optic fiber and can be easily replaced if damaged.
[0019] 7. Solution number 7 is the similar to solution number 4, except that instead of the bluetooth or other wireless device it uses optic fiber or fibers for the communication between the cellular phone and the proxy device. Preferably, the optic fiber can be folded or released (for example around part of the proxy, or around a small wheel which is attached either to the phone or to the proxy, preferably with a spring), so that the proxy can also be used further away from the user's head, as in solution 4. Preferably, the optic fiber can be easily replaced if damaged.
[0020] If for example infrared or other light wavelength is used for the short range communication instead of electromagnetic communications, in any of the variations without optic fibers, there are a number of possible ways for enabling automatic frequency hoping in order to avoid interference between users who are close to each other, or in other words, improve privacy and avoid cross-talk with devices of nearby users. This can be done for example by encrypting the communication between the phone and the proxy, preferably in a different way for each pair. One preferable way of accomplishing the preferably automatic frequency selection for example with visible light or infrared is for example to use LED arrays or matrices (for example in a chip) with a preferably large number of LEDs of different frequencies each, so that the appropriate LEDs can be easily chosen. Another preferably way of doing this is to use for example a smaller set of LEDs and use various power combinations to create the desired combined frequency, similar to a color pixel on a color LCD screen, preferably with a lens or prism that combines the lights together. Another possible way of accomplishing this is for example to use a set of differently colored filters in front of a LED or LEDs covering a certain range of frequencies so that different filters or combinations of filters can be automatically chosen and moved (for example by rotation) in order to change the frequency. Similarly, the light decoders in these solutions are preferably capable of similarly tuning-in to the chosen frequency, for example by a using a similar matrix of detectors, each responsive to a given frequency, or using a smaller set of detectors and measuring the amplitude in each of them, or using a similar set of changeable filters in front of the detectors. Another possible variation is using for example tunable diodes. Another possible way to avoid collisions with other devices is for example to use, instead of or in addition to frequency hopping, a choice of different broadcast characteristics, such as for example using fatter or thinner bits, or using different bit placement within each frame of communication. Various combinations of these solutions can also be used. These solutions can be used also independently of any other features of this invention and can be used for example also for free-air optical communication between normal headsets and cellular phones.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 is a schematic block diagram of a preferable arrangement of the system.
[0022] [0022]FIG. 2 is a schematic illustration of preferable changes in the cellular phone's design and function in solution number 1.
[0023] [0023]FIG. 3 is a schematic illustration of a preferable proxy device's design and function in solution number 1.
[0024] [0024]FIG. 4 is a schematic illustration of preferable changes in the cellular phone's design and function in solution number 2.
[0025] [0025]FIG. 5 is a schematic illustration of a preferable proxy device's design and function in solution number 2.
[0026] [0026]FIG. 6 is a schematic illustration of a preferable proxy device's design and function in solution number 3.
[0027] [0027]FIG. 7 is a schematic block diagram of a preferable variation where the proxy contains just a transducer and the phone can use a separate headset.
[0028] [0028]FIG. 8 is an illustration of a preferable variation where the proxy device is coupled to the cellular phone and extends the position of the cellular antenna away from the user's head, as for example in solutions 4 & 7.
IMPORTANT CLARIFICATION AND GLOSSARY
[0029] Throughout the patent when variations or various solutions are mentioned, it is also possible to use various combinations of these variations or of elements in them, and when combinations are used, it is also possible to use at least some elements in them separately or in other combinations. These variations are preferably in different embodiments. In other words: certain features of the invention, which are described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. All these drawings are just exemplary diagrams. They should not be interpreted as literal positioning or shapes or angles or sizes of the various parts, such as the blutooth chip, the antennas, etc. Also, throughout this patent, including its summary and the claims, when the words “on one end” or “on the other end” or “at one end” or “at the other end” or “on one hand” or “on the other hand” are used, they are meant conceptually and not literally—so for example the bluetooth and the cellular antenna on the proxy are not necessarily positioned opposite to each other physically. Also, throughout this patent including its summary and the claims, whenever the word “bluetooth” is used it means either bluetooth or any other device for short range low energy wireless communication at any acceptable frequency (including, for example, also infra-red), and including for example UWB (Ultra Wide Band) or any other type of pulse-based communication. Also, whenever the word “cell” or “cells” is used throughout this patent, including the summary and the claims, it means interchangeably either cell or cells and it means all types of communication cells wherever they are, such as for example cells on the ground, cells in the air, such as on balloons, satellites, etc. Also, the term “optic fiber” or “optic fibers” or “fiber optic” as used throughout the text, including the claims, are always meant interchangeably to be either optic fiber or optic fibers. Also, the term “cellular phone” or “mobile phone” or “wireless phone” or “phone” or “telephone” as used throughout the patent, including the claims, can mean any device for communications through wireless and/or cellular technology, including for example Internet-enabled cellular phones, such as the Japanese DoCoMo, 3 rd Generation cellular communication devices, palm computers communicating by cellular and/or wireless technology, etc. Whenever the words “he” or “his” or “him” is used about the user, it is just for clarity and convenience, and it refers of course also to female users. The various reversals in roles between the phone and the headset or proxy can be described also in terms of transferring various features between them. So for example the phone can be described alternatively as a headset which has been given most or all of the features of a phone until it becomes practically a phone, and vice versa.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] All of the descriptions in this and other sections are intended to be illustrative examples and not limiting.
[0031] Referring to FIG. 1, the cellular phone ( 1 ) communicates (both ways—to and from) through short range low energy wireless communication ( 2 ) with the proxy device ( 3 ), which communicates on its other end through normal cellphone microwave broadcast ( 4 ) (both ways—to and from) with the cellular company's nearest cell or cells ( 5 ).
[0032] Referring to FIG. 2, the cellular phone ( 21 ) contains a bluetooth chip or similar device ( 22 ) and uses it to communicate (both ways—to and from) with the proxy device ( 31 in FIG. 3) instead of communicating normally with the cellular company's nearest cell or cells ( 5 in FIG. 1). In another possible variation, preferably, it has also still the normal cellular antenna and its related circuitry ( 23 ), so that it can communicate normally with the cellular company's nearest cell or cells ( 5 in FIG. 1) whenever it is unable to reach the proxy ( 31 in FIG. 3) for any reason. In such a case, preferably it will flash a sound and/or light ( 24 ), in order to alert the user that he is again exposed to the microwave radiation, and preferably keep repeating the sound every few seconds to alert the user that he is still in unsafe mode. Preferably, this will be a short high pitch beep from its built-in speaker.
[0033] Referring to FIG. 3, the proxy device ( 31 ) contains a bluetooth chip or similar device ( 32 ) and uses it to communicate (both ways—to and from) with the cellular phone ( 21 in FIG. 2) on one hand, and on the other hand has a typical cellular phone's antenna and related circuitry ( 33 ) for communicating (both ways—to and from) with the cellular company's nearest cell or cells ( 5 in FIG. 1). Preferably, it uses a CPU or CPUs ( 34 ) for its cellular protocol and for converting information (to and from) between the protocols of its two ends.
[0034] Referring to FIG. 4, the cellular phone ( 41 ) contains a bluetooth chip or similar device ( 42 ) and uses it to communicate (both ways—to and from) with the proxy device ( 51 in FIG. 5) instead of communicating normally with the cellular company's nearest cell or cells ( 5 in FIG. 1). It has also still the normal cellular antenna and its related circuitry ( 43 ), so that it can communicate normally with the cellular company's nearest cell or cells ( 5 in FIG. 1) whenever it senses that the user is communicating with it through the proxy device ( 51 in FIG. 5) (acting as headset) instead of directly, and preferably also whenever the user is using the cellular phone directly but the phone is unable to reach the proxy ( 51 in FIG. 5) for any reason. In the second case, preferably it will flash a sound and/or light ( 44 ), in order to alert the user that he is again exposed to the microwave radiation. The cellular phone has the appropriate logic, preferably in its CPU or CPUs ( 49 ), to operate in 2 different modes when communicating with the proxy ( 51 in FIG. 5), so that in mode 1 (when the user is using the phone directly) the phone preferably activates normally its built-in speaker ( 46 ) and microphone ( 47 ), disables its normal cellular antenna and related circuitry ( 43 ), and preferably tells the proxy device ( 51 in FIG. 5) through a special signal or signals on the bluetooth or similar channel to act as normal proxy. Preferably, the cellular phone can detect that it is being used directly by the user through either the fact that it is open and/or some keys have been pressed or through receiving a signal or signals from the proxy ( 51 in FIG. 5) (through the bluetooth or similar channel) indicating that the proxy is not currently being used as a headset. In mode 2 (when the user is using the proxy device ( 51 in FIG. 5) as headset), preferably the cellular phone_ deactivates its built-in speaker ( 46 ) and microphone ( 47 ), activates its normal cellular antenna and related circuitry ( 43 ), and preferably tells the proxy device ( 51 in FIG. 5) through a special signal or signals on the bluetooth channel to act as headset. Preferably, the cellular phone can detect that it is not being used directly by the user through either the fact that it is closed and/or no keys have been pressed or through receiving a signal or signals from the proxy ( 51 in FIG. 5) (through the bluetooth or similar channel) indicating that the proxy is indeed currently being used as a headset. Preferably, the logic will also alert the user though an appropriate message to any situation where the proxy ( 51 in FIG. 5) and cellular phone are not in compatible modes and are unable to agree on the mode for some reason.
[0035] Referring to FIG. 5, the proxy device ( 51 ) contains a bluetooth chip or similar device ( 52 ) and uses it to communicate (both ways—to and from) with the cellular phone ( 41 in FIG. 4) on one hand, and on the other hand has a typical cellular phone's antenna and related circuitry ( 53 ) for communicating (both ways—to and from) with the cellular company's nearest cell or cells ( 5 in FIG. 1). Preferably, it uses a CPU or CPU's ( 54 ) for its cellular protocol and for converting information (to and from) between its two protocols. In addition to this, it also has a preferably high level earphone ( 55 ) and microphone ( 56 ) and preferably it has the shape of a headset, or for example it folds when used as normal proxy and opens to the shape of a headset when used as headset. The proxy device also has the appropriate logic, preferably in its CPU or CPUs ( 54 ), to operate in 2 different modes when communicating with the cellular phone ( 41 in FIG. 4), so that in mode 1 (when the user is using the phone directly) the proxy preferably deactivates its earphone ( 55 ) and microphone ( 56 ), activates its normal cellular antenna and related circuitry ( 53 ), and preferably tells the cellular phone ( 41 in FIG. 4) through a special signal or signals on the bluetooth or similar channel that it is currently functioning as normal proxy. Preferably, the proxy device can detect that it is being used as normal proxy through either the fact that it is in closed position and/or some switch has been changed or through receiving a signal or signals from the cellular phone ( 41 in FIG. 4) (through the bluetooth or similar channel) indicating that the phone is currently being used directly by the user. In mode 2 (when the user is using the proxy device as headset), preferably the proxy activates its earphone ( 55 ) and microphone ( 56 ), deactivates its normal cellular antenna and related circuitry ( 53 ), and preferably tells the cellular phone ( 41 in FIG. 4) through a special signal or signals on the bluetooth channel that it is currently being used as headset. Preferably, the proxy device can detect that it is currently being used by the user as headset through either the fact that it is open and/or some switch has been changed or through receiving a signal or signals from the cellular phone ( 41 in FIG. 4) (through the bluetooth channel) indicating that the phone is currently regarding the proxy as a headset. Preferably, the logic will also alert the user though an appropriate message to any situation where the proxy and cellular phone ( 41 in FIG. 4) are not in compatible modes and are unable to agree on the mode for some reason. Preferably, since it has also already the cellular antenna and its related circuitry ( 53 ), it can also sense whenever the cellular phone ( 41 in FIG. 4) is unreachable or does not function for some reason and then it can temporarily communicate directly with the cellular company's nearest cell or cells ( 5 in FIG. 1). In such a case, preferably it will indicate a sound (preferably a short high pitch beep from its normal earphone), in order to alert the user that he is again exposed to the microwave radiation, and preferably keep repeating this sound every few seconds to alert the user that he is still in unsafe mode. Preferably, this Proxy device has also voice command activation in order to dial automatically when used as headset, however, it might have also a small set of keys that enable the user to dial directly if for some reason the voice activation does not function. The logic for the voice command activation may be either in the proxy or in the cellular phone. Or it might have the set of keys instead of the voice command
[0036] Referring to FIG. 6, the proxy device ( 61 ) can have for example two cellular antennas and use one of them ( 62 ) to communicate (both ways—to and from) with the cellular phone ( 1 in FIG. 1) on one hand, and use the second cellular antenna ( 63 when communicating with the cellular phone and for converting) on the other hand for communicating (both ways—to and from) with the cellular company's nearest cell or cells ( 5 in FIG. 1). Preferably, it uses a CPU or CPUs ( 64 ) for imitating the appropriate cell protocols information (to and from) between its two protocols. Another possible variation is that for making it cheaper, the proxy has just one cellular antenna instead of two. In that case, preferably in different embodiments, it can use for example fast timesharing so that the same antenna can communicate intermittently with the cellular phone ( 1 in FIG. 1) and with the cellular company's cell or cells ( 5 in FIG. 1), or use different frequencies to communicate at the same time both with said cellular phone ( 1 in FIG. 1) and with the cellular company's cells ( 5 in FIG. 1).
[0037] Referring to FIG. 7, the cellular phone ( 1 ) communicates (both ways—to and from) through short range low energy wireless communication ( 2 ) with the proxy device ( 3 ), which communicates on its other end, typically through normal cellphone microwave broadcast ( 4 ) (both ways—to and from) with the cellular company's nearest cell or cells ( 5 ). In this variation the proxy preferably includes just the transducer, in other words it just translates between the two communication protocols, using a normal cellular antenna on one end and a bluetooth chip or other short range low energy wireless communication device on the other end. The phone ( 1 ) preferably contains the short range communication device instead of the cellular antenna, in order to save energy & cost and preferably contains a lighter battery. In addition to this, the phone ( 1 ) can also communicate with optional headset ( 7 ) for example through short range low energy wireless communication or through normal wire ( 6 ).
[0038] Referring to FIG. 8, the proxy device ( 83 ) is preferably physically coupled to the cellular phone ( 81 ) at any convenient position or angle and extends the position of the cellular antenna ( 84 ) away from the user's head as far as conveniently possible, preferably on a non-metallic rod ( 82 ), such as plastic. Preferably, this angle can be changed by the user in various directions, preferably by using a ball-type hinge. So, for example, the proxy ( 83 ) can position the cellular antenna ( 84 ) upwards away from the head, or downwards, at the opposite direction than usual, as far from the brain as conveniently possible. Preferably, this rod ( 82 ) can be easily made longer or shorter by the user (preferably by telescopic design, or for example by being divided into several parts with at least one hinge between each two parts, so that it can be folded and unfolded in various ways). However, in this solution the cellular antenna's distance from the brain might be smaller than in the other solutions, so the reduction of the level of radiation that the user's brain is exposed to might be smaller than in the other solutions. Preferably, the proxy can be also easily removed from its position on the phone and can also be used further away from the user's head, as described in solution 1 of the patent summary. Preferably, for recharging, the proxy can either be removed from its position on the phone and moved to the appropriate socket, or for example an auxiliary wire can be used that is removed when not recharging.
[0039] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications, expansions and other applications of the invention may be made which are included within the scope of the present invention, as would be obvious to those skilled in the art. | Cellular phones are becoming more common and popular amongst all sectors of the population for business and private conversations, including many children, with about 500 Million users worldwide, and about 300,000 new joiners each day. There is much concern and there is already some accumulating evidence that the Microwave emission transmitted by the cellular antenna that is held close to user's head may have deleterious effects on the user, such as for example brain or eye cancer, and possibly even more so for children. One of the most common ways to try to avoid these problems has been the usage of personal earphones with microphone, but on Apr. 4, 2000 it was published worldwide that a research conducted by the “Which?” consumer Magazine in Britain found that in fact the earphone and its cable can act as an Antenna and also expose the user to the microwave radiation. The present invention solves the above problem in using earphones with cellular phones by a reverse and more sophisticated solution than short range wireless earphones, and also solves the problem that many people don't like using headsets at all. | 7 |
[0001] The disclosure of Japanese Patent Application Nos. 2006-0009362 filed Jan. 18, 2006, 2006-009382 filed Jan. 18, 2006, and 2006-009434 filed Jan. 18, 2006, including specifications, drawings and claims is incorporated herein by reference in their entirety.
BACKGROUND
[0002] The present invention relates to an antenna device operable to receive an electric wave of digital radio broadcasting.
[0003] A digital radio receiver which is operable to receive a satellite wave or ground wave and allows a person to hear digital radio broadcasting has been developed, and has been put to practical use in United States. The digital radio receiver can be mounted on a mobile station, such as a vehicle, or can be installed inside a building to receive an electric wave the frequency band of which is about 2.3 GHz and to allow a person to hear the radio broadcasting. Since the frequency of the received electric wave is about 2.3 GHz, a received wavelength (resonant wavelength) λ is about 128.3 mm. In addition, once the satellite wave is received at the earth station, the frequency thereof is shifted a little and is retransmitted as a linearly polarized wave that is the ground wave.
[0004] Since an electric wave having a frequency band of about 2.3 GHz is used in the digital radio broadcasting, it is preferable that an antenna device receiving the electric wave is installed outdoors. Therefore, when the digital radio receiver is mounted on a vehicle or the like, it is provided, for example, in the outside of the vehicle such as a roof thereof in many cases. On the other hand, when the digital radio receiver is used inside a building, the antenna device is installed in a roof, a balcony or the like in many cases.
[0005] Here, the directional sensitivity of this type of antenna device is omni-directional. However, in order to ensure the best sensitivity, the antenna device is required to be constructed such that the wave angle of the antenna device is adjusted to avoid an electric wave shielding object. The related-art antenna device for home use which has an angle adjustment function is disclosed in, for example, Japanese Patent Publication No. 2004-289514A. The related-art antenna device disclosed in Japanese Patent Publication No. 2004-289514A includes a base portion, and an antenna portion the angle of which is adjustable with respect to the base portion via a hinge portion. The hinge portion has a hinge base, two hinge bushes, two coil springs, two washer, and two screws. The hinge base is formed on an end of a ceiling surface of the base case of the base portion, and has two tapered shafts protruding from both ends of the hinge base, respectively. Each of the hinge bushes has a tapered inner peripheral surface and is fitted into each of the shafts of the hinge base. The coil spring is fitted into each of the shafts on which the hinge bush is mounted. A screw is fastened via the washer to an end surface of each of the shafts on which the hinge bush and the coil spring are mounted. The biasing force of the spring generates a frictional force between the outer peripheral surface of the shaft of the hinge base and the inner peripheral surface of the hinge bush when the hinge bush rotates. The antenna portion is joined to the hinge bush and is capable of being opened and closed at an arbitrary angle relative to the base portion. The frictional force between the shaft of the hinge base and the hinge bush causes the antenna device to be fixed at a constant angle without rotation when an external force is not applied thereto. On the other hand, when an external force larger than the frictional force between the shaft of the hinge base and the hinge bush is applied to the antenna portion, the antenna portion rotates, and can be adjusted to an arbitrary angle. The angle adjustment is performed as follows, for example. A user manually adjusts the angle of the antenna portion such that the best level of a broadcasting signal or the best sound quality of audio information received by a digital radio receiver is maintained, while confirming the level or the sound quality.
[0006] As described above, in the related-art antenna device including the example described in Japanese Patent Publication No. 2004-289514A, the number of the hinge bush, the coil spring, the washer, and the screw is two, respectively. For this reason, it is disadvantageous in decreasing the size and the weight of the antenna device. Also, since the cost of parts is high and since a number of manufacturing processes are required, it is disadvantageous the decreasing the cost thereof.
[0007] A satellite wave, especially a circularly polarized wave is used for digital radio broadcasting. As disclosed in Japanese Patent Publication No. 2005-20644A, an related-art antenna device including an antenna module corresponding to the circularly polarized wave has a ground plate, an antenna plate disposed to face the ground plate at a distance therefrom, an antenna probe disposed between the ground plate and the antenna plate, and a probe holder made of resin for holding the antenna probe. The probe holder is formed with a groove portion in which the antenna probe is to be disposed. A member made of an insulating material, such as a tape, for electrically insulating the antenna probe and the antenna plate is attached onto the ceiling surface of the probe holder in which the antenna probe is to be disposed.
[0008] For the purpose of realizing miniaturization, lightness, reliability, and cost reduction of the antenna device including the related-art antenna device disclosed Japanese Patent Publication No. 2005-20644A, it is effective to realize miniaturization, lightness, reliability, and cost reduction of the antenna module. Specifically, it is considered that, for example, the ground plate and the antenna plate is miniaturized. However, in a case where the ground plate and the antenna plate are miniaturized, there is a possibility that an electrostatic capacitance of the antenna module, which is required for the antenna device to exhibit a sufficient gain, may decrease.
[0009] An antenna device used for a GPS (global positioning system) using a satellite wave similarly to a digital radio broadcasting system, particularly an antenna device suitable for being installed on a roof of a vehicle is disclosed in Japanese Patent Publication No. 2005-109688A. The related-art antenna device disclosed in Japanese Patent Publication No. 2005-109688A includes a top cover, a bottom cover, an antenna module, a packing member, and a signal line. Since the packing member is disposed in a connecting portion between the bottom plate and the top plate to ensure adherence therebetween to perform a water-proof function, it is also called as a water-proof packing. The packing member has a generally angular-shaped plate part including a wide angular-shaped frame part and a bush part covering the periphery of the signal line in the position of a cut-out portion formed in the top cover. Since the frame part and the bush part are integrally formed with each other, the number of parts and manufacturing processes is small compared to a case in which the both members are separately formed. The water-proof function is realized as follows. A water-proof rib having an angular and frame shape is formed inside the top cover to correspond to the angular-shaped frame part of the plate part of the packing member. The-packing member and the bottom plate are fastened to the top cover with a plurality of screws. The fastening pressure at this time causes the leading end of the water-proof rib of the top cover to be pressed against the angular-shaped frame part of the packing member, thereby realizing the water-proof function.
[0010] As described above, in the antenna device including the related-art antenna device disclosed in Japanese Patent Publication No. 2005-109688A, when the fastening pressures by the plurality of screws are different from one another or the fastening pressures by the screws are too large, there is a possibility that a gap may be formed between the water-proof rib formed in the top cover and the packing member. As a result, there is a possibility that the water-proof property realized by the packing member may deteriorate.
SUMMARY
[0011] It is therefore an object of the present invention to provide an antenna device which is small in size and light in weight, and which is low in cost because the cost of parts and the number of manufacturing processes is small.
[0012] It is also an object of the invention to provide an antenna device which is small in size, light in weight and low in cost, while the antenna device can exhibit a high gain.
[0013] It is also an object of the invention to provide an antenna device having an excellent water-proof property.
[0014] In order to achieve the above described objects, according to the invention, there is provided an antenna device, comprising:
[0015] a base portion;
[0016] a hinge portion formed on the base portion;
[0017] an antenna portion attached to the hinge portion so as to be pivotable thereabout, wherein:
[0018] the hinge portion includes:
a hinge base having a first shaft formed on one end thereof, a second shaft formed on the other end thereof, and a first protrusion formed on an outer periphery of the second shaft; and a hinge bush rotatably mounted on the first shaft and engaged with the antenna portion;
[0021] the antenna portion is formed with a hole surrounding the outer periphery of the second shaft;
[0022] a projection is formed on an inner periphery of the hole; and
[0023] the first protrusion is brought into contact with the projection when the antenna portion is pivoted so as to define a predetermined angle with respect to the base portion.
[0024] According to the invention, there is also provided antenna device, comprising:
[0025] an antenna portion;
[0026] a hinge portion formed on the antenna portion;
[0027] a base portion attached to the hinge portion so as to be pivotable thereabout, wherein:
[0028] the hinge portion includes:
a hinge base having a first shaft formed on one end thereof, a second shaft formed on the other end thereof, and a first protrusion formed on an outer periphery of the second shaft; and a hinge bush rotatably mounted on the first shaft and engaged with the base potion;
[0031] the base portion is formed with a hole surrounding the outer periphery of the second shaft;
[0032] a projection is formed on an inner periphery of the hole; and
[0033] the first protrusion is brought into contact with the projection when the base portion is pivoted so as to define a predetermined angle with respect to the antenna portion.
[0034] The antenna portion may be operable to pivot about the hinge portion in a first direction.
[0035] The hinge base may have a second protrusion formed on the outer periphery of the second shaft.
[0036] The antenna portion may have a wall portion formed on the inner periphery of the antenna portion.
[0037] The wall portion may be brought into contact with the second protrusion so that the antenna portion is not pivot in the first direction when the antenna portion defines a right angle with respect to the base portion.
[0038] The base portion may be operable to pivot about the hinge portion in a first direction.
[0039] The base portion may have a wall portion formed on the inner periphery of the base portion.
[0040] The wall portion is brought into contact with the second protrusion so that the base portion is not pivot in the first direction when the base portion defines a right angle with respect to the antenna portion.
[0041] The hinge bush may be comprised of at least one of ABS resin, ASA resin, and PC resin.
[0042] With this configuration, the antenna device is small in size and is light in weight, and the antenna device is low in cost the cost of parts is low and the number of manufacturing processes is small.
[0043] According to the invention, there is also provided an antenna device, comprising:
[0044] a ground plate adapted to be electrically grounded;
[0045] an antenna plate;
[0046] an antenna probe feeding to the antenna plate;
[0047] a probe holder which is comprised of resin, interposed between the ground plate and the antenna plate, and holding the antenna probe, wherein:
[0048] an area of the probe holder is equal to or larger than at least one of an area of the ground plate and an area of the antenna plate.
[0049] A face of the probe holder, which opposes the antenna plate may be formed with a groove.
[0050] The antenna probe may be inserted into the groove.
[0051] A projection may be formed in the groove so as to hold the antenna probe in the groove
[0052] A depth of the groove and a position in the groove where the projection is formed may be set so that the antenna probe is disposed at a predetermined distance from the antenna plate so as to be electrically insulated from the antenna plate.
[0053] The antenna device may further comprise:
[0054] a ground member which is comprised of metal, disposed under the ground plate, and an area of which is equal to or larger than the ground plate, wherein:
[0055] electric potential of the ground member is equal to electric potential of the ground plate.
[0056] The ground member may include at least one of a metal sheet, a metal sheet adhered on a bottom cover of the antenna device, and conductive coating material coating the bottom cover of the antenna device.
[0057] With this configuration, the antenna device is small in size, is light in weight and is low in cost, while the antenna device can exhibit a high gain. Further, the antenna device exhibits an excellent shielding effect against both an incoming noise and a radiation noise.
[0058] According to the invention, there is also provided An antenna device, comprising:
[0059] a first cover;
[0060] a second cover coupled to the first cover and defining a space therebetween;
[0061] an antenna module accommodated in the space;
[0062] a signal line electrically connected to the antenna module and led out from the space;
[0063] a packing member interposed between the first cover and the second cover so as to close the space in a waterproofing manner, wherein:
[0064] the packing member includes a frame portion formed with a groove and a bush portion into which the signal line fitted; and
[0065] the second cover includes a rib fitted into the groove.
[0066] A width of the groove may be substantially equal to a thickness of the rib.
[0067] The antenna module may be accommodated within the frame.
[0068] The packing member may be comprised of silicone rubber.
[0069] The rib may include a rib end portion disposed in the vicinity of the bush portion.
[0070] The groove may include a groove end portion disposed in the vicinity of the bush portion.
[0071] The rib end portion may be fitted into the groove end portion.
[0072] The antenna device according to the present invention has an excellent water-proof property.
BRIEF DESCRIPTION OF THE DRAWINGS
[0073] The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:
[0074] FIG. 1 is a schematic exploded view showing an antenna device according to an embodiment of the present invention;
[0075] FIGS. 2A and 2B are respectively a perspective view and a partially enlarged view showing a packing member of the antenna device shown in FIG. 1 ;
[0076] FIGS. 3A to 3 D are respectively a plan view, a cross-sectional view, another cross-sectional view, and a partially enlarged view showing the packing member shown in FIG. 1 ;
[0077] FIGS. 4A to 4 E are respectively a bottom view, a cross-sectional view, a plan view, another bottom view, and a partially enlarged view showing the top cover of the antenna device shown in FIG. 1 ;
[0078] FIG. 5 is a partial cross-sectional view showing a water-proof structure of the antenna device according to the embodiment of the present invention;
[0079] FIGS. 6A and 6B are views showing an angle adjusting structure of the antenna device according to the embodiment of the present invention;
[0080] FIGS. 7A and 7B are alternative views showing an angle adjusting structure of the antenna device according to the embodiment of the present invention;
[0081] FIGS. 8A and 8B are further alternative views showing an angle adjusting structure of the antenna device according to the embodiment of the present invention; and
[0082] FIGS. 9A to 9 C are respectively a plan view, a cross-sectional view, and another cross-sectional view showing a probe holder of the antenna device according to the embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0083] Hereinafter, an embodiment of an antenna device according to the invention will be discussed with reference to the accompanying drawings.
[0084] An antenna device according to the present invention is an antenna device for a digital radio receiver, and particularly an antenna device for home use assuming that the antenna device is also installed in outdoor places, such as a roof and a balcony, in addition to indoors, and is connected to a digital radio receiver installed indoors.
[0085] The directional sensitivity of the antenna device is omni-directional. However, in order to ensure best sensitivity, it is desirable that the antenna device is constructed such that the attachment angle of the antenna device is adjusted to avoid an electric wave shielding object. For this reason, the present antenna for home use has an angle adjustment function.
[0086] As shown in FIG. 1 , the antenna device according to the present invention has the angle adjustment function. Specifically, the present antenna device has a base portion 20 which can be attached to a wall surface or the like, an antenna portion 10 accommodating an antenna module 13 , and a hinge portion 30 for connecting the antenna portion 10 to the base portion 20 such that the angle therebetween can be adjusted.
[0087] The base portion 20 includes a base case 21 and a base plate 22 . The base case 21 and the base plate 22 are coupled together using a plurality of screws 23 . Four rubber pads 24 are adhered to the base plate 22 . The present antenna device can be mounted inside an oriel window of a building. Further, the base plate 22 is provided with hooking holes 222 , the present antenna device can be hooked and attached to screws or hooks provided in a wall.
[0088] The antenna portion 10 includes a top cover 11 , a bottom cover 12 , an antenna module 13 which is mounted inside the top cover, a packing member 14 , and a ground sheet 17 (the detailed description thereof will be made below). The top cover 11 and the bottom cover 12 are coupled together by a plurality of screws 18 .
[0089] The packing member 14 is made of, for example, a resin material, such as silicone rubber or EPDM rubber(ethylene propylene rubber). Since the packing member 14 is arranged at a connecting portion between the bottom cover 12 and the top cover 11 to ensure the adherence therebetween to perform a water-proof function, it is also called as a water-proof packing. As shown in FIG. 2A , the packing member 14 has a frame part 141 having a rectangular frame shape with large width, and a bush part 142 covering the periphery of a signal line (not shown) at the position of a cut-out part 123 formed at the top cover 11 . Since the packing member 14 is constructed such that the frame part 141 and the bush part 142 are integrally formed, the number of parts and manufacturing processes is small compared to the case in which both the members are separately formed. The packing member 14 is useful in terms of miniaturization, lightness, reliability, and cost reduction.
[0090] The present antenna device has a water-proof structure realizing a water-proof function between the top cover 11 and the bottom cover 12 . As shown in FIGS. 4A to 4 E, a water-proof lib 113 protruding in a generally rectangular frame shape is formed inside the top cover 11 . On the other hand, as shown in FIGS. 2B, 3A to 3 D, the generally rectangular-shaped frame part 141 of the packing member 14 is provided with a generally rectangular and frame-shaped groove 141 a which corresponds to the protruded water-proof rib 113 having the generally rectangular frame shape. When the bottom cover 12 and the top cover 11 are assembled together with the packing member 14 therebetween, a leading end of the water-proof lib 113 of the top cover 11 , as shown in FIG. 5 , fits into the groove 141 a of the frame part 141 of the packing member 14 . Further, when the top cover 11 and the bottom cover 12 are fastened together using the plurality of screws 18 , the water-proof rib 113 is pressed against the groove 141 a , thereby realizing the water-proof function. The width of the groove 141 a is substantially equal to the thickness of the water-proof rib 113 .
[0091] Further, in the generally rectangular-shaped frame part 141 of the packing member 14 , as shown in FIG. 3D , a groove end 141 b which continues from the groove 141 a is formed to the vicinity of the bush part 142 . The groove end 141 b has a pocket shape. On the other hand, as shown in FIG. 4E , a rib end 114 which continues from the water-proof rib is formed inside the top cover 11 . In the protruded portion of the signal line, the bush part 142 is fitted into a bush accommodating portion of the top cover 11 , thereby exhibiting a water-proof effect, as well as the rib end 114 is fitted into the groove end 141 b , thereby increasing a water-proof property.
[0092] In the water-proof structure of the present antenna device, the contact area between the packing member 14 and the water-proof rib 113 is large. For this reason, any gap is not created between the water-proof rib 113 of the top cover 11 and the packing member 14 , even in a case in which the fastening pressures by the plurality of screws 18 are different from one another, or the fastening pressures by the screws 18 are relatively large. Therefore, the present antenna device has an excellent water-proof property. Further, when the water-proof rib 113 of the top cover 11 fits into the groove 141 a of the packing member 14 , the packing member 14 is not dislocated in the horizontal direction.
[0093] In the present antenna device, the angle of the antenna portion 10 with respect to the base portion 20 can be adjusted via the hinge portion 30 . As shown in FIGS. 1, 6A and 6 B, the hinge portion 30 includes a hinge base 31 , a hinge bush 32 , a coil spring 33 , a washer 34 and a screw 35 . The hinge base 31 is provided at an end of a ceiling surface of a base case 21 of the base portion 20 , and extends parallel to the ceiling surface of the base case 21 . An end of the hinge base 31 is formed with a first shaft 312 . The first shaft 312 has a base 312 a having a tapered outer peripheral surface and a shaft-body-shaped leading end 312 b extending from the base 312 a . The hinge bush 32 is made of a low frictional resin material, such as ABA, ASA, or PC, has a tapered inner peripheral surface, and is fitted around the base 312 a of the first shaft 312 such that it can rotate with friction. The coil spring 33 is fitted onto the leading end 312 b on which the hinge bush 32 is mounted. The screw 35 is fastened via the washer 34 to an end surface of the first shaft 312 on which the hinge bush 32 and the coil spring 33 is mounted. The biasing force of the coil spring 33 generates a frictional force between the outer peripheral surface of the base 312 a of the first shaft 312 and the inner peripheral surface of the hinge bush 32 to cause the hinge bush 32 to slide with respect to the first shaft 312 .
[0094] The hinge bush 32 is sandwiched and fixed between the top cover 11 and the bottom cover 12 . The frictional force between the base 312 a of the first shaft 312 and the hinge bush 32 causes the antenna portion 10 to be fixed at a constant angle without rotation when an external force is not applied thereto. On the other hand, the antenna portion 10 can be rotated and adjusted to an arbitrary angle when an external force larger than the frictional force between the base 312 a of the first shaft 312 and the hinge bush 32 is applied thereto.
[0095] In the present invention, the angle of the hinge portion 30 can be adjusted within a range of 0 to 90 degrees. The angle adjustment is performed as follows, for example. A user manually adjusts the angle of the antenna portion 10 such that the best level of a broadcasting signal or the best sound quality of audio information received by a digital radio receiver via the present antenna device is maintained, while confirming the level or the sound quality.
[0096] Further, in the present invention, the hinge base may be formed at an end of the antenna, and the hinge bush may be fixed to an end of the base portion.
[0097] In the angle adjusting structure of the present antenna device, the number of the hinge bush 32 of the hinge portion 30 , the coil spring 33 , the washer 34 , and the screw 35 is one, respectively. Therefore, the antenna device is small in size and is light in weight, and the antenna device is low in cost since the cost of parts is low and the number of manufacturing processes is small.
[0098] Further, As shown in FIGS. 7A and 7B and FIGS. 8A and 8B , the other end of the hinge base 31 is formed with a second shaft 313 . The second shaft 313 has a pair of cantilever pieces 313 a formed by splitting the end of a shaft body of the second shaft, and a convex portion 313 b formed on an outer peripheral surface of one of the cantilever pieces. The cantilever piece 313 a functions as a cantilever spring. On the other hand, inner peripheral surface portions 122 are formed at ends of the top cover 11 and the bottom over 12 so as to surround the second shaft. Each inner peripheral surface portion 122 has a protrusion 122 a formed corresponding to a predetermined position of the convex portion 313 b when the antenna portion 10 is opened and closed with respect to the base portion 20 . In the present embodiment, the predetermined position of the convex portion 313 b is a position just before the angle of the antenna portion 10 with respect to the base portion 20 becomes 0 degree. When the antenna portion 10 is closed toward 0 degree as shown in FIGS. 8A and 8B from a state where the antenna device is opened as shown in FIGS. 7A and 7B , the convex portion 313 b supported by the cantilever piece 313 a rides over the protrusion 122 a . At this time, a click feeling is created. Further, when the antenna portion 10 is completely closed at 0 degree, the convex portion 313 b supported by the cantilever piece 313 a is regulated by the protrusion 122 a . Therefore, the antenna portion 10 is not inadvertently opened (floated) as long as an external force exceeding the elastic force of the cantilever piece 313 a is not applied thereto.
[0099] The second shaft 313 further includes a second convex portion 313 c formed on an outer peripheral surface of the root thereof. On the other hand, the inner peripheral surface portion 122 further has a wall portion 122 b which abuts on the second convex portion 313 c to prevent the antenna portion 10 from having an angle larger than 90 degrees when the antenna portion 10 forms an angle of 90 degrees with respect to the base portion 20 .
[0100] In addition, in the present invention, the second shaft along with the hinge base may be formed in the antenna portion, while the inner peripheral surface portion may be formed in the base portion. Further, any one of the convex portion formed in the second shaft and the protrusion formed in the inner peripheral portion has preferably a low frictional property.
[0101] As shown in FIG. 1 , the antenna module 13 includes a ground plate 134 , an antenna plate 131 , an antenna probe 132 , a probe holder 133 , an LNA (low noise amplifier) 137 , and a shielding case 138 .
[0102] The ground plate 134 is made of metal, and has a generally square shape. The antenna plate 131 is made of metal, has a generally square shape, and is arranged to face the ground plate 134 with a distance therebetween. The antenna probe 132 is made of metal and is located between the ground plate 134 and the antenna plate 131 . The probe holder 133 is made of ABS resin, has a generally cubic shape, and holds the antenna probe 132 in a fixed position.
[0103] The plate surface area of each of the ground plate 134 and the antenna plate 131 is made smaller than that of the related-art antenna device. When the ground plate and the antenna plate are miniaturized, there is a possibility that the electrostatic capacitance of the antenna module decreases and the antenna device does not exhibit a sufficient gain. However, the present antenna device increases a specific dielectric constant between the ground plate 134 and the antenna plate 131 to ensure a sufficient electrostatic capacitance. For this reason, the present antenna device can exhibit a high gain. Specifically, the probe holder 133 provided between the ground plate 134 and the antenna plate 131 has a size equal to or lager than the facing area between the ground plate 134 and the antenna plate 131 . That is, most of the space between the ground plate 134 and the antenna plate 131 is filled with resin member (probe holder 133 ). Since the resin has a specific dielectric constant larger than that of air, the antenna module 13 has a sufficient electrostatic capacitance.
[0104] As shown in FIG. 9A to 9 C, a generally L-shaped groove 133 b is formed in a ceiling surface of the probe holder 133 . The antenna probe 132 is inserted into the groove 133 b . Since a protrusion 133 c is formed in the groove 133 b , the antenna probe 132 inserted into the groove 133 b is securely held within the groove 133 b without being removed unnecessarily. The depth of the groove 133 b and the height of the protrusion 133 c are set such that the antenna probe 132 held by the probe holder 133 and the antenna plate 131 are spaced from each other with a predetermined distance therebetween and are electrically insulated from each other. For this reason, an insulating member needs not to be mounted on the antenna probe held by the probe holder, whereby the number of parts of the antenna device may be reduced.
[0105] An end of the antenna probe 132 and a signal line (not shown) are electrically connected to the LNA 137 . The shielding case 138 is soldered to the LNA 137 . The LNA 137 covered with the shielding case 138 is adhered to the ground plate 134 with an insulating tape 136 . The ground plate 134 to which the LNA 137 is adhered is attached to the inside the top cover 11 with a plurality of screws 135 . The signal line is led out of the antenna portion 10 via the bush part 142 of the packing member 14 located in the cut-out position formed in the bottom cover 12 .
[0106] As described above, the plate surface area of each of the ground plate 134 and the antenna plate 131 is smaller than that of the conventional one. When the ground plate is miniaturized, there is a possibility that the shielding effect against an incoming noise and a radiation noise may deteriorate. However, since the present antenna device includes an additional ground means, it has a shielding effect against the incoming noise and the radiation noise. That is, the ground means is composed of a ground sheet 17 shown in FIG. 1 . The ground sheet 17 is composed of an aluminum adhesive seal, has a size equal to or larger than the area of the ground plate 134 , and is adhered to an inner bottom surface of the bottom cover 12 . The ground sheet 17 is arranged in a state in which it is spaced with a predetermined distance from the ground plate 134 and the shielding case 138 . The additional ground means according to the present invention may be a metal plate or conductive paint applied onto the inner bottom surface of the bottom cover 12 . The conductive paint may contain, for example, copper or aluminum.
[0107] The present invention has been described with reference to the preferred embodiment, but the present invention is not limited the above-described embodiment. For example, the present invention is not limited to a home antenna for a digital radio receiver and may be applied to an antenna device for receiving a GPS signal, and an antenna device for mobile communication for receiving satellite waves and ground waves. | A hinge portion is formed on the base portion. An antenna portion is attached to the hinge portion so as to be pivotable thereabout. The hinge portion includes a hinge base having a first shaft formed on one end thereof, a second shaft formed on the other end thereof, and a first protrusion formed on an outer periphery of the second shaft, and a hinge bush rotatably mounted on the first shaft and engaged with the antenna portion. The antenna portion is formed with a hole surrounding the outer periphery of the second shaft. A projection is formed on an inner periphery of the hole. The first protrusion is brought into contact with the projection when the antenna portion is pivoted so as to define a predetermined angle with respect to the base portion. | 7 |
BACKGROUND
[0001] Minimally-invasive medical therapies are increasingly gaining importance. In the treatment of coronary heart disease, the surgical bypass operation on the heart is clearly declined in favor of balloon dilation (PTCA=percutaneous transluminal coronary angioplasty) and the insertion of a stent. In arterial fibrillation, ablation in the atrium has established itself in recent years. Minimally-invasive procedures are also clearly increasing in the fields of biopsies, spinal column therapies and tumor ablation.
[0002] Medical imaging that shows the vessels, organs and medical instruments in the organism in real time remains a requirement in all minimally-invasive interventions. Image artifacts thereby arise due to body and organ movement (for example due to breathing). For example, given a lung tumor the tumor moves between 1 and 2 cm during one breathing cycle.
[0003] Modern imaging devices such as computer tomographs have what is known as respiration gating; the breathing cycle is thereby taken into account in the image reconstruction, and the radiologist acquires exposures in which the movement artifacts that arise due to breathing have been corrected.
[0004] A solution which takes into account the respiratory movement in radiation therapy is known from U.S. Pat. No. 5,764,723, “Apparatus and Method to Gate a Source for Radiation Therapy”.
[0005] In biopsies or tumor ablation, the therapy needle must still be introduced manually by the physician into the organ area to be treated. For this the patient is required to hold his breath, or the physician attempts to insert the needle while estimating the breathing cycle. This method is very dependent on the cooperation of the patient and the manual / surgical skill of the physician.
[0006] The solution described in pending Siemens AG German Patent Application 2008P0365 DE, (“Movement-Controlled, in Particular Breathing-Controlled Needle Guidance”), improves the guidance of rigid instruments in an organism and reduces the requirements for the cooperation readiness of the patient or the skillfulness of the physician. However, one disadvantage is that the respiratory movement of the patient must be correctly detected.
SUMMARY
[0007] It is an object to find a solution that permits a safe insertion and guidance of an instrument, independent of the patient and the skill of the physician.
[0008] In a method or system for minimally-invasive therapy on a patient, a minimally-invasive therapy apparatus is provided. While performing the minimally-invasive therapy on the patient with the minimally-invasive therapy apparatus, the patient is ventilated with a jet ventilator to reduce a magnitude of the patient's breathing and increase a frequency of the patient's breathing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a side partial cross-sectional view illustrating a prior art jet ventilator needle injecting pulsating ventilated air into a nose of a patient;
[0010] FIG. 2 is a graph showing a normal breathing curve and tumor movement during needle insertion into the tumor without respiration or with conventional respiration according to the prior art;
[0011] FIG. 3 is a graph showing a breathing curve and tumor movement when a jet ventilation device is employed during needle insertion into a tumor;
[0012] FIG. 4 is a schematic illustration of a jet ventilator being used for a patient to be scanned by a robotic x-ray radiator and detector system with an associated image system connected to the jet ventilator for processing control;
[0013] FIG. 5 is a schematic illustration of the patient being respirated with a jet ventilator and undergoing a scan with a robotic x-ray radiation and detector during robotic needle insertion, such as into a tumor, and the use of a data bus for processing control by the use of the jet ventilator with at least one or more system modules;
[0014] FIG. 6 is a block diagram of a first embodiment of a patient positioning table and a robotic x-ray detector system wherein a data bus with other system modules is connected with the jet ventilator via a gating image connection unit; and
[0015] FIG. 7 is a second embodiment of a patient positioning table and robotic x-ray detector system where the jet ventilator is connected to a data line with other system modules via a physiological signal processing unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to preferred embodiments/best mode illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, and such alterations and further modifications in the illustrated devices and such further applications of the principles of the invention as illustrated as would normally occur to one skilled in the art to which the invention related are included.
[0017] According to one preferred embodiment, the patient is respirated with what is known as a jet (high-frequency) ventilator during an intervention (advantageously for a needle insertion and guidance procedure such as into a tumor).
[0018] Such a jet ventilator is available from the company http://www.acutronic-medical.ch or http://www.bunl.com/controls.html. U.S. Pat. No. 5,239,994, “Jet Ventilator System”, also discloses a jet ventilator. This document is incorporated herein.
[0019] Due to the high-frequency respiration (60 to 700 respiration cycles per minute) and reduced magnitude of the respiration, a distinct rising and falling of the ribcage no longer occurs, rather only a high-frequency oscillation of the lungs with very small movement amplitude that barely causes interfering image artifacts.
[0020] Two techniques can thereby be used: a) insertion of a respiration tube through the nose (see “Effectiveness of transnasal jet Ventilation—a teaching aid”, James R. Boyce); or b) insertion of a respiration tube via the trachea (see “Conventional Methods are Unsuccessful Provide Oxygenation and Ventilation When A Safe, Quick, and Temporary Way To: *Percutaneous Transtracheal Jet Ventilation”, Rajesh G. Patel). Technique a) above is preferred.
[0021] Particularly advantageous is the integration of this device into an angiographic/cardiological x-ray system comprised of high voltage generator, x-ray radiator(s), radiation diaphragm, image display unit(s), patient table, radiator and detector tripod with a digital image system, in particular a DynaCT and/or DynaCT Card x-ray device (of Siemens AG). A device with which both angiographic x-ray exposures and CT-like images can be re-constructed is disclosed in DE 102005016472 “Operating Method for an X-ray System, Corresponding Operating Method for a Computer and Corresponding Subjects”. A gating signal can thereby additionally be derived by the jet ventilator and be taken into account in the image reconstruction. The respiration curve can be displayed at the imaging unit.
[0022] The guidance of the instrument (needle) can thereby be implemented by hand by the medical personnel or via a needle guidance robot that does not need to be respiration-controlled due to the low movement amplitude. Alternatively, a signal can additionally be lifted from the jet ventilator in order to further improve the robot control.
[0023] For example, the high-frequency respiration can be used by such methods in the following methods or combinations: a) x-ray systems; b) sonography, including IVUS; c) radioscopy (fluoroscopy); d) angiographic and cardiological x-ray systems; e) optical coherence tomography (OCT); f) positron emission tomography (PET); g) SPECT; h) computer tomography; i) nuclear magnetic resonance tomography, including intravascular/intracardial MR; j) optical exposures, including endoscopy; k) fluorescence and optical markers (molecular imaging); and l) radiation therapy or particle therapy
[0024] A great advantage of the preferred embodiment lies in the avoidance of movements of the ribcage with large amplitude, which cause unwanted organ, tumor and vessel movements during the intervention.
[0025] Preferred embodiments will now be described in greater detail with respect to FIGS. 1-7 .
[0026] FIG. 1 shows a prior art jet ventilator 10 with a ventilator output 11 comprising a hose 11 A and needle 11 B inserted at a nose 100 A of a patient 100 .
[0027] FIG. 2 shows a known prior art relationship between movement of a tumor 7 A, 7 B as a result of respiration of a patient having a breathing curve 5 without respiration or with a conventional prior art respirator A needle robot 6 must therefore track the movement of the tumor, which is very disadvantageous as previously indicated.
[0028] FIG. 3 shows a needle robot 6 for injecting a needle into a tumor 4 A, 4 B which does not move nearly as much as the tumor does in previous FIG. 2 since a jet ventilation is employed so that the patient's breathing curve has much smaller peaks and valleys as indicated at 3 . Thus with the preferred embodiment, it is much easier for the needle robot to insert a needle to take a sample from the tumor over a time period corresponding to a plurality of small undulations of the patient's breathing curve 3 .
[0029] FIG. 4 shows an illustration of a patient 12 respirated, such as by a needle to the patient's nose, via a ventilator output line 11 to a jet ventilator 10 . The patient lies on a table 16 for undergoing an x-ray scan by use of a floor-mounted articulated arm robot 15 with a C-shaped arm 15 A with x-ray radiator 15 B and detector 15 C.
[0030] The jet ventilator 10 has a signal output time 10 A connected via an interface 13 between the jet ventilator 10 and an image system 14 for the x-ray system 15 . Thus the ventilator can control the image system to take a count of even small undulations in the patient's breathing curve.
[0031] In FIG. 5 a system is provided with a robot 1 for insertion of an intervention needle 2 with movement compensation. As shown in FIG. 5 , the patient 12 may undergo an x-ray radiation scan for needle guidance by the robotic system 15 during the intervention with the needle robot 1 for example to obtain a biopsy from a patient's tumor while the patient 12 is being ventilated by a jet ventilator 10 via ventilator output line 11 and ventilator needle 11 B. The x-ray radiator system 15 with x-ray radiator 15 B and detector 15 C is used to continuously image the procedure to insure proper replacement of the needle into the tumor while the patient is being respirated by the jet ventilator.
[0032] In FIG. 5 , the jet ventilator 10 connects an output signal line 10 A through interface 13 to an interface unit 30 for movement sensor and movement evaluation. Interface 30 is connected to a data bus 3 which also connects to: a synchronization unit 31 for movement deactivation, image correction, and robot control; a robot unit 32 ; an image processing unit 33 with movement correction; and a planning unit 34 for planning the intervention, and determination of start and target coordinates for guidance of the needle 2 of the needle robot 1 . The method with jet-ventilator will also work without a needle robot when the operator uses his hands
[0033] A patient-proximal control unit 300 for the x-ray system 15 with C-shaped arm 15 A and the needle robot 1 is provided for proper placement of the patient 12 on the patient table 16 with respect to the needle robot 1 and the x-ray system 15 .
[0034] FIG. 6 is a first embodiment of a patient 12 on a patient table 16 using a jet ventilator 10 via ventilator output line 11 while undergoing an x-ray scan with a robotic x-ray unit 15 having C-shaped arm 15 A with x-ray radiator 15 B and detector 15 C. Jet ventilator 10 is connected via signal output 10 A through an interface 13 to an image correction unit 21 operating on the gating principle. As in FIG. 5 , the patient is lying on patient table 16 and is being imaged by use of the x-ray system 15 . A high voltage generator 26 connects with detector 15 C and is controlled by a system controller 27 connected to the patient table 16 control input. A power supply unit 18 is also provided for the system.
[0035] As shown in FIG. 6 , a common data bus 17 is provided connected to a number of units. The data bus 17 connects to a display unit for x-ray images 19 with an associated user I/O unit 20 . The aforementioned image correction unit 21 also connects to the data bus 17 . The same is true of a physiological signal processing unit 22 and an image processing unit for x-ray images 24 (including 3D reconstruction and with soft tissue processor).
[0036] A pre-processing unit for x-ray images unit 23 connects to the x-ray radiator 15 B and also to the data bus 17 .
[0037] The aforementioned system controller 27 connects to the data bus 17 along with a calibration unit 25 , image data memory 28 , and interface for patient data and image data 29 . This interface has an input and output for CT or MR exposures and an input and output for HIS.
[0038] FIG. 7 is a second embodiment employing the jet ventilator 10 ventilating, via ventilator output line 11 , a patient 12 undergoing an x-ray scan with robotic x-ray unit 15 having C-shaped arm 15 A with x-ray radiator 15 B and detector 15 C. The jet ventilator 10 has a signal output at 10 A connected through an interface 13 to a physiological signal processing unit (respiration, CO 2 ). An output of the unit 22 connects to a common data bus 17 . A power supply unit 18 is also provided.
[0039] Also connected to the data bus 17 are the same units 18 , 19 , 20 , 21 , 23 , 24 , 25 , 27 , 25 , 28 , and 29 described for FIG. 6 . A high voltage generator 26 and system controller 27 are also provided connected to the patient table 16 , as was the case in FIG. 6 .
[0040] While preferred embodiments have been illustrated and described in detail in the drawings and foregoing description, the same are to be considered as illustrative and not restrictive in character, it being understood that only some possible embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention both now or in the future are desired to be protected. | In a method or system for minimally-invasive therapy on a patient, a minimally-invasive therapy apparatus is provided. While performing the minimally-invasive therapy on the patient with a minimally-invasive therapy apparatus, the patient is ventilated with a jet ventilator to reduce a magnitude of the patient's breathing and increase a frequency of the patient's breathing. | 0 |
BACKGROUND OF THE INVENTION
The invention relates to a process and to a device for measuring the thickness of transparent materials. More particularly, but not exclusively, the invention concerns the thickness measurement of glass materials and, even more precisely, the thickness measurement of flat glass, in particular float glass.
The general quality requirements demanded by customers and the savings which can be made by keeping to the bottom of the thickness tolerance range require very rigorous monitoring of thickness in the mass production of flat glass.
Of the techniques normally used for measuring thickness, the most precise methods which can be used in transparent media are optical methods. Among these, interferometric techniques, previously limited to laboratory measurements, have progressively found industrial applications.
For example, document FR-A-2 435 019 proposes a technique for measuring the thickness of a thin film which consists in exposing the thin film to infrared light spectroscopically split by rapid scanning over a range of wavelengths which is predetermined as a function of the nature of the film so as to create a spectrum of interference fringes between the reflected rays, the extreme points of which are determined. The technique is limited to thicknesses necessarily smaller than 30 μm. It consists in counting the interference fringes of rays reflected by the surfaces of the film. Such a method cannot be used for measuring the thickness of flat glass on a float glass production line whose thickness varies from less than 1 mm to 2 cm.
Another document, WO 95/22740, describes an interference method for determining the wall thickness of bottles during their manufacture.
The process is characterized in that a light beam with modulated optical frequency is emitted, in that two light beams or rays, reflected by each of the surfaces of a wall of a material, are received, in that interference is created between them and in that the path difference δ of the interference signal is determined. A laser diode is used as the illumination source, and this is modulated by modulation of the optical frequency of the beam. Of the rays scattered by the two walls, two parallel rays are selected. The device of the invention makes it possible to take measurements 0.3 msec apart on each sensor. It is thus possible to explore every millimetre of the periphery of a bottle in rotation.
This technique, in which measurements are taken using isolated rays scattered by the surfaces, requires relatively powerful lasers (>30 mW), which may present drawbacks. It will be difficult to use the same method with parallel reflected beams because of the prismaticity of the support and, in particular, of float glass which is always prismatic in the edge zones.
Although providing good precision on the absolute thickness measurement, the method of WO 95/22740 is less well suited to following local thickness variations. This type of measurement is, however, very important for detecting the drifts in the nominal thickness of flat glass on its production line as early as possible. Furthermore, the method of WO 95/22740 does not make it possible to measure thicknesses smaller than 0.7 mm.
SUMMARY OF THE INVENTION
The object of the invention to which the present patent application relates is to develop the techniques above while improving their performance.
The invention proposes a process for measuring the thickness (e) of a transparent material with refractive index (n), in which a light beam with modulated optical frequency is focused, where two light beams or rays, reflected by each of the surfaces of the transparent material, are received, where interference between them is created, where the number of oscillations per modulation period of the interference signal is determined and where the path difference (δ) between the two beams and the thickness (e) of the transparent material are deduced, and in which the phase shift (Δφ) of the said interference signal is also determined.
This determination of the phase shift between the two signals recorded in succession can then be used to deduce other characteristics of the said material. It may in particular be applied to the precise measurement of local thickness variations, in particular of a strip of float glass. Similarly, it is proposed to apply it to measuring the thickness of a thin transparent material, preferably more than 0.2 mm.
The process of the invention is characterized in that the light beam with modulated optical frequency is emitted by a laser diode with distributed Bragg reflector (DBR).
Another characteristic is that the beams reflected by the surfaces of the transparent material are received after specular reflection and, lastly, another is that the focused light beam converges before reaching the surfaces of the transparent material so that it is divergent at the surfaces of the said transparent material which it reaches.
All these characteristics, taken in isolation or as a group, make it possible to obtain the local thickness variations by receiving the interference signal on a detector followed by:
digitizing the signal if necessary;
obtaining the ratio of the interference signal to the modulation of the intensity;
band-pass filtering the ratio;
determining the extrema of the resultant signal for the measurement at time k;
determining the time between the corresponding extrema of two successive measurements (k and k+1);
calculating the ratio of the preceding time to the corresponding period and multiplying it by 2 π to obtain the phase shift Δφ;
calculating the thickness variation by the formula: Δ e = λ 0 · Δ ϕ 4 n π
with:
λ 0 =wavelength of a laser diode without modulation,
Δφ=phase shift,
n=refractive index.
By virtue of this method of evaluating the thickness variations, the process of the invention makes it possible to monitor them with precision better than 1.10 −8 m. Such precision very advantageously makes it possible to measure, for example, dioptric defects of float glass. The dioptric defect is, as is known, mathematically connected with the second derivative of the thickness profile.
The invention also relates to the device intended to implement the process. It has, in particular, a light source with DBR laser diode, means for receiving an interference signal and a computer which successively:
digitizes the signals;
takes the ratio of the interference signal and the intensity modulation;
band-pass filters the digitized ratio;
determines the extrema;
determines the time between the corresponding extrema of two successive measurements (k and k+1);
takes the ratio of the preceding times to the corresponding periods and multiplies it by 2 π to obtain the phase shift;
calculates the thickness variation by the formula: Δ e = λ 0 · Δ ϕ 4 n π
In one variant, the device has fibre-optic waveguides for transporting the light emitted by the laser diode and/or reflected by the surfaces of the transparent object. This technique makes it possible to work in hostile environments, such as in heat or in dust. It is thus possible to take measurements as soon as the sample to be monitored, for example float glass, leaves its processing device, in particular the float bath.
One variant also has avalanche photodiodes as the reception means.
The figures and the description which follow will make it possible to understand how the invention operates and to appreciate the advantages thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the optical principle of the measurement device.
FIG. 2 represents the interference zone of plane glass with parallel faces;
FIG. 3 represents the same zone with the reception lens; for its part;
FIG. 4 shows the interference fringes in a plane P of the said interference zone;
FIG. 5 presents a schematic view of the electronic device for processing the optical signal.
FIG. 6 shows the indexes of the extrema for two successive measurements (k and k+1) in the case of emission DBR laser diode;
FIG. 7 and FIG. 8 represent the signals V int , V mod and V div with a conventional laser diode, respectively for 1.67 mm and 3.83 mm;
FIGS. 9 and 10 represent, for a DBR laser diode, the division signal during the modulation rise, respectively for flat glass with thickness 1.67 mm and 3.83 mm; and
FIG. 11 shows a thickness profile measured according to the invention in comparison with manual measurements.
DETAILED DESCRIPTION OF THE INVENTION
During the manufacture of flat glass, it is necessary to measure the thickness profile of the float strip for two reasons: quality control and hot process control.
For quality control, the monitoring of the thickness profile of the float strip is currently carried out on-line (square) using commercial instruments. These operate either by absorption of gamma radiation or by optical means.
Instruments which operate by absorption of gamma radiation certainly do not have a future because instruments using a radioactive source are required to be phased out owing to restrictive national and international regulations.
Instruments which operate by optical means use a geometrical optics method. A laser beam reflected by the glass gives two spots which correspond to the two faces. The distance between these two spots is proportional to the thickness of the glass.
These instruments are unreliable because they are sensitive to the distance from the glass and, above all, to the tilt of the glass. They are also difficult to adjust. The major drawback with these instruments is that they do not have sufficient accuracy, especially for thin and ultra thin glass, that is to say with a thickness less than 0.5 mm.
In order to control the process, it is preferable to install an instrument for hot thickness measurement, that is to say immediately after the float outlet. This will make it possible to monitor the thickness profile immediately after each adjustment in the float, without having to wait for the glass to leave the lehr in order to be able to monitor it. It would thus be possible to obtain better adjustment for the float, so that the thickness profile is flatter and the thickness is at the lower limit of the specification. This would lead to a considerable weight saving.
Hot thickness monitoring will also make it possible to reduce the production losses when changing thickness, especially for thick glass.
It is therefore necessary to develop a sensor capable of measuring the thickness profile when hot as well as when cold, which is reliable, robust, accurate (±0.005 mm) and economical.
It is well known that, at the output of an interferometer illuminated by a monochromatic source, the interference signal received by a photodetector is given by: V int ∝ I 0 ( 1 + C · cos ( 2 π λ δ ) ) , ( 1 )
the sign ∝ indicating “proportional to”.
Interference techniques are well known, in particular from the document WO 95/22740 which describes the use of interference when employing a source with modulated optical frequency.
In an interferometer, if the optical frequency or 1/λ can be modulated by linear modulation in the shape of a symmetrical triangle, the following can be written: 1 λ = 1 λ 0 + g 0 ( t ) · 1 T / 2 ( 2 )
Here, λ 0 denotes the initial laser wavelength without modulation, g 0 (t) represents the shape with which 1/λ is modulated as a function of time, denoted by t, and T represents the period of the triangular modulation.
In this case, for a fixed path difference δ, the interference signal varies as a function of the wavelength which is time-modulated. This is a heterodyne interference phenomenon.
Substituting equation (2) into equation (1) gives, for time t, the interference signal during the rise or fall of the signal given by: V int ∝ I o ( 1 + C · ( ϕ 0 + g 1 ( t ) ) ) ( 3 )
where: ϕ 0 = 2 π λ 0 δ (3-1) g 1 ( t ) = 2 π g 0 ( t ) T / 2 δ (3-2)
For a conventional laser diode, on condition that there is no mode jumping, the wavelength is linearly modulated: 1 λ = 1 λ 0 + Δ ( 1 λ ) · t T / 2 ( 4 )
In this case: V int ∝ I 0 ( 1 + C · cos ( ϕ 0 + ω t ) ) ( 5 )
with: ϕ 0 = 2 π λ 0 δ (6-1) ω = 2 π · Δ ( 1 λ ) δ T / 2 (6-2)
From equation (5), it can be seen that when using a conventional laser diode, linear modulation of the optical frequency (or 1/λ) leads to a sinusoidal signal whose angular frequency is ω. During a half-period of the triangular modulation, there are N oscillations: N = ω · T / 2 2 π
which gives: N = Δ ( 1 λ ) · δ = Δ λ λ 0 2 · δ ( 7 )
where Δλ represents the wavelength excursion without mode jumping of a conventional laser diode.
It should be emphasized here that the number N is not necessarily an integer. It is proportional to the path difference δ. It is a useful working parameter because it is normalized in relation to the modulation frequency 1 /T.
Knowing the characteristics of the laser diode used, that is to say Δλ and λ 0 , measuring N (number of oscillations per half-period of the triangular modulation) makes it possible to determine the path difference δ.
For our application, the glass can be regarded as a reflection interferometer. If light is incident on a pane of glass, it will be reflected by the two faces of the glass. These two reflections interfere with a path difference:
δ=2ne (8)
where n and e respectively represent the refractive index and the thickness of the glass.
By measuring the path difference δ, and knowing the refractive index n of the glass, the thickness e can be deduced. In contrast to the relative measurement method which will be set out in the paragraph below, the measurement taken is an absolute measurement.
If a more in-depth analysis of equation (5) is made, it can be seen that the signal has not only an angular frequency ω which is proportional to the thickness, but also a phase φ 0 which is proportional to the path difference δ, and therefore to the thickness e (see equation (3-1)).
Measuring the angular frequency ω or N allows us to determine the thickness e of the glass. At the same time, measuring the phase variation gives us access to information about the variation in thickness.
For measurement k and measurement k+1, which are two successive measurements, if the sensor is moved relative to a sample of glass, the corresponding thicknesses are respectively e (k) and e (k+1) and the corresponding phases are respectively φ 0(k) and φ 0(k+1) . The following is obtained: ϕ 0 ( k ) = 2 0 2 ne ( k ) and ϕ 0 ( k + 1 ) = 2 0 ne ( k + 1 )
The phase shift is given by: Δ ϕ ( k ) = ϕ 0 ( k + 1 ) - ϕ 0 ( k ) = 2 π λ 0 2 n · Δ e ( k ) ( 9 )
with:
Δ e (k) =( e (k+1) −e (k) ) (10)
It should be recalled that λ 0 is the wavelength of the laser diode without modulation, and is therefore a fixed parameter. Knowing the refractive index n of the glass, measuring the phase shift allows us to determine the thickness variation Δe (k) at measurement k according to equation (9).
For a phase shift of 10°, which is readily measurable, if the index of the glass is 1.52 and the wavelength λ 0 780 nm, the thickness variation is 7 nm. The method therefore has a capacity for measuring thickness variations which is better than 10 nm, i.e. 1.10 −8 m. This capacity allows us to measure the dioptric defects of float glass, for example.
The invention is based on the principle which has just been explained.
In a variant, instead of a conventional laser diode it uses a DBR laser diode (Distributed Bragg Reflector—See T. HIRATA, M. MAEDA, M. SUEHIRO, H. HOSOMATSU “Fabrication and Characterisation of GaAs-AlGaAs Tunable Laser Diodes with DBR and Phase-Control Sections Integrated by Compositional Disordering of a Quantum Well”, IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 27, N° 6, JUNE 1991).
For a typical conventional laser diode with λ 0 =780 nm and Δλ=0,24 nm, the following is obtained for e=1 mm:
N=1.2
A typical DBR laser diode has the following characteristics: λ 0 =850 nm and Δλ=2 nm, and the following is obtained for e=1 mm:
N=8.4
It may be noted that by using a DBR laser diode, even for a thickness of 0.5 mm, there are still more than 4 oscillations for taking a frequency measurement in order to determine the thickness, which is quite comfortable. It is therefore possible to measure the thickness of glass which is thin or even ultra thin (0.2 mm).
It should, however, be emphasized that unlike with the conventional laser diode, the wavelength modulation of a DBR laser diode is not linear for a linear modulation of the current. In other words, the function g 0 (t) in expression (2) is a non-linear function of time for a DBR laser diode.
In general, the interference signal can be represented by:
V int ∝I 0 (1+C·cos (φ 0 +e·g(t))) (11)
with:
g ( t )= b 1 t+b 2 t 2 +b 3 t 3 + . . . for DBR laser diode (12)
and: g ( t ) = ( 2 π · Δ ( 1 λ ) 2 n T / 2 ) t for conventional laser diode ( 13 )
FIG. 1 presents the optical system in a schematic form.
The light source, a conventional laser diode or DBR laser diode, is shown at 1. The image of its output A is formed at B by a lens 16 . The position of the point B in relation to the sample of glass 2 is not arbitrary. The fact that this new light source gives a divergent beam in the glass makes it possible to obtain a sizeable interference zone, represented at 3 in FIG. 2, even in the case when the glass is prismatic, which can reduce the aperture of the zone 3 . The detection part of the signal is thus not at risk of being outside the zone where the measurement is possible, even in the very prismatic parts of a strip of float glass, at the edges.
The light sources used in the tests were either a conventional laser diode HL 7851 G (Hitachi) with a power of 50 mW and a wavelength λ of 780 nm, or an 852 nm Yokogawa YL 85 XT DBR laser diode.
In order to avoid excessive heating of the optoelectronic systems, a variant of the invention proposes that optical fibres be employed when using the method of the invention in hot production zones. The light from a laser diode is then coupled into a single-mode optical fibre, which is not represented in the figures.
The light rays output from the secondary source B are reflected by the two surfaces of the sample (specular reflection which gives an intensity much greater than that of rays scattered by the surfaces as in the prior art. The invention is, however, also compatible with scattered rays).
The reflected beams seem to come from two point sources B 1 and B 2 (FIG. 2 ), the distance between them being proportional to the thickness e of the sample, which is what is actually to be measured. For the measurement, the emission side and the reception side of the system are combined in FIG. 1, the rectangle 4 containing all of the device according to the invention. In addition to the emission part described above, the reception part therefore also lies in it. There is thus a lens 6 which focuses at C an element C′ of the interference zone 3 , either directly onto the detection component or, as in FIGS. 1 and 3, onto the input of a multi-mode optical fibre 5 . The optical fibre is connected to a detector; an avalanche photodiode (APD) is advantageously used.
FIG. 4 represents a section of the interference zone 3 at the point C′ picked up by the lens 6 . The indication Φ C′ represents what is actually “seen” by the lens 6 and the optical fibre 5 .
The measurement system is represented in FIG. 5 . What is essential is a computer 8 , for example a PC, which manages the optoelectronic devices and analyses and processes the detected optical signal. The light source 1 , a conventional or DBR laser diode lying inside the electronics unit 11 , is powered by a power supply unit 9 . The latter receives a modulation signal V mod from the computer 8 via the cable 10 . The optical signal output by the laser diode 1 is transmitted by the single-mode optical fibre 12 which runs through a sheath 7 as far as the measurement head 4 . The multimode other optical fibre 5 which passes through the same sheath 7 collects the optical signal at C and transmits it to the detector 13 , which is preferably an avalanche photodiode.
The PC system is in fact a signal processing system. It comprises:
a divider card,
digital signal processing software.
These two parts will be dealt with in more detail in the next paragraph.
The heterodyne interferometry method uses linear current modulation to modulate the laser diode wavelength. The laser diode light intensity is, however, also time-modulated.
Re-examining expression (11), which applies for a conventional laser diode and also for a DBR laser diode, it can be seen that if the intensity I 0 is time-modulated in any way, it will not be possible to extract the terms (angular frequency and phase) of the sinusoidal signal.
For a conventional laser diode, a linear current modulation leads to a linear modulation of the intensity I 0 . In the case of a DBR laser diode, however, a linear current modulation leads to a non-linear modulation of the intensity I 0 .
The solution to this problem consists in dividing the interfering signal by the intensity modulation V mod =I 0 (t). In this case, the followings obtained: V div = V int V mod ∝ 1 + C · cos ( ϕ 0 + e · g ( t ) ) ( 14 )
with:
g ( t )=b 1 t+b 2 t 2 +b 3 t 3 + . . . for DBR laser diode (15-1)
and: g ( t ) = ( 2 π · Δ ( 1 λ ) 2 n T / 2 ) t for conventional laser diode (15-2)
The division signal obtained is independent of the modulation of the laser diode intensity. It is now only a pure sinusoidal signal, which allows us to utilize it and determine the thickness.
In the specific case of the sensor given, the division is performed digitally by a DIVIDER electronics card in PC format. Installed in a PC, it carries out the division and at the same time also provides the source of triangular modulation V mod for the laser diode power supply. This divider card is denoted 14 in FIG. 5 .
The PC receives the division result transmitted by the DIVIDER. The digital processing can then begin in the unit 15 .
For our application, the triangular modulation frequency may be 2 kHz. For a modulation rise or fall, 250 division points are available.
The first processing operation is band-pass filtering. This leads to elimination of some of the noise and the DC level of V div , but without thereby deforming the sinusoidal signal.
The second processing operation consists in determining the positions of the extrema, that is to say the numerical indices (between 1 and 250) of maxima and minima in the sinusoidal signal. The last processing operation is for determining the thickness.
For a rising or falling division signal V div , the indices for the extrema can be expressed by a vector M. FIG. 6 shows these indices of the extrema for two successive measurements k and k+1. In this figure, a frequency modulation (concertina effect) can be seen, which corresponds to the case of a DBR laser diode. Nevertheless, this frequency modulation may represent the general case of the signal, both for a conventional laser diode and for a DBR laser diode.
For measurement k, a vector M k is obtained which contains L indices of the extrema:
M k =[m j k ]=[m 1 k , m 2 k , m 3 k , m 4 k , . . . , m L k ]
where:
1<m j k <250 and 1≦j≦L
In order to measure the thickness per se (absolute measurement), the following procedure is adopted.
Since the division signal is in digital form, the time term (t) loses its traditional meaning. The concept of time is replaced by an integer which varies from 1 to 250.
Knowing the function g(t) according to expression (14), the following is obtained:
e·[g ( m j+1 k )− g ( m j k )]=π (16)
This means that for the two successive extrema corresponding respectively to t=m j k and t=m j+1 k , the phase changes by π or 180°. Since for a given thickness and for a given laser diode there are L extrema, the thickness e can be determined in terms of least squares by minimizing the function below: Y = ∑ j = 1 L - 1 [ e · ( g ( m j + 1 k ) - g ( m j k ) ) - π ] 2
The minimum of the function Y exists when dY/de=0, which gives: e = π ∑ j = 1 L - 1 ( g ( m j + 1 k ) - g ( m j k ) ) ∑ j = 1 L - 1 ( g ( m j + 1 k ) - g ( m k k ) ) 2 ( 17 )
This formula for determining thickness applies both for a conventional laser diode and for a DBR laser diode.
In order to carry out the measurement of thickness variations (relative measurement), it is necessary to calculate the derivative of the thickness profile.
For measurement k+1, the following is obtained:
M k+1 =[m j k+1 ]=[m 1 k+1 , m 2 k+1 , m 3 k+1 , m 4 k+1 , . . . , m L k+1 ]
If vector M k from measurement k is recorded in the memory of the computer, the phase shift between measurement k+1 and measurement k is given by: Δϕ ( k ) = ϕ 0 ( k + 1 ) - ϕ 0 ( k ) = 2 π m k k + 1 - m j k m j + 2 k + 1 - m j k + 1 ( 18 )
This is true so long as m j k+1 and m j k both correspond to the maximum or both to the minimum of a sinusoid.
Hence, if the thickness of the glass has not varied by more than λ 0 /(4n), the thickness variation between the measurement k+1 and measurement k is, according to expression (9): Δ e ( k ) = Δ e ( k + 1 ) - Δ e ( k ) = λ 0 2 n Δϕ ( k ) 2 π ( 19 )
This formulation for determining the derivative of the thickness profile applies both for a conventional laser diode and for a DBR laser diode.
All that remains is to combine the calculation mode for the “absolute” thickness with that for the “relative” thickness in order to obtain a complete unique result.
The thickness profile can be given by:
e (k) =e (1) +Δe (k) (20)
with: Δ e ( k ) = ∑ j = 2 k Δ e ( j - 1 ) ( 21 )
where e (1) denotes the thickness at the first measurement (k=1). Here, k designates the measurement number and naturally represents time.
The relative measurement mode makes it possible to obtain the thickness variation profile Δe (k) with sub-micron precision. All that remains to be done in order obtain the final thickness profile is to find the constant e (1) .
The absolute measurement mode allows us to determine e (1) . In order to do this, it is sufficient to take one measurement in absolute mode before the relative measurements. In practice, however, one measurement taken at random is not stable, in view of the phenomena perturbing the signal during the measurement.
One of the remedies to this problem is to take the average of a certain number of measurements in absolute mode, which directly gives the constant e (1) . However, the thickness variation of the product may not always allow enough time to make a large number of measurements and take their average. It seems to us that the best solution consists in determining the constant e (1) by the least squares method.
For a thickness profile measurement, a thickness profile in absolute mode is obtained at M measurement points:
e A(k) for k=1 to M
The thickness variation profile at M measurement points is thus obtained in relative mode:
Δe (k) for k=1 to M
Here, k=1 and k=M correspond respectively to the start and the end of the profile.
It is necessary to find the constant e (1) such that [e (1) +Δe (k) ] is as close as possible to e A(k) in terms of least squares. The constant e (1) can therefore be determined by minimizing the following function: Q = ∑ k = 1 M [ ( e ( 1 ) + Δ e ( k ) ) - e A ( k ) ] 2
The minimum of this function exists for dQ/de (1) , which leads e ( 1 ) = 1 M ∑ k = 1 M ( e A ( k ) - Δ e ( k ) ) ( 22 )
To summarize, it may be stated that the thickness profile on a float line can be measured in the following way:
1) the measurements are taken while the sensor is moving transversely over the strip,
2) the absolute and relative measurements are taken for all the measurement points on the strip, which gives us the thickness profile e A(k) in absolute mode and the thickness variation profile Δe (k) in relative mode,
3) the final thickness profile is [e (1) +Δe (k) ] where e (1) is determined by expression (22).
In order to verify the method of the invention, various tests were carried out.
First, a measurement series was taken using a conventional laser diode, on flat glasses with various thicknesses between 1 mm and 20 mm. FIG. 7 shows the interference signal V int , the modulation signal V mod and the division signal V div for a thickness of 1.67 mm and FIG. 8 for a thickness of 3.83 mm.
The method shows measurement precision of the same order as that of a micrometer screw gauge, ±5 μm.
Using a DBR laser diode, a series of measurements was taken on flat glasses with various thicknesses between 0.3 mm and 5 mm. FIG. 9 and FIG. 10 show the signals for a thickness of 1.67 mm and a thickness of 3.83 mm.
Comparing FIGS. 7 and 9, it is easy to see that during a rise (or fall) of the triangular modulation, for the same thickness, there are many more oscillations with a DBR laser diode than with a conventional laser diode. At the same time, the concertina effect on the division signal obtained with the DBR laser diode is clearly visible, which reflects the nonlinearity of the function g(t) for the DBR laser diode.
The measurement of thickness with a DBR laser diode requires, above all, accurate knowledge of the function g(t), that is to say the nonlinearity of wavelength modulation by linear current modulation. This function can be determined by mathematical fitting. This consists in determining all the parameters in the following expressions: V div = V int V mod ∝ 1 + C · cos ( ϕ 0 + e · g ( t ) )
with:
g ( t )= b 1 t+b 2 t 2 +b 3 t 3 + . . . (°/mm) for t=1 to 250
so that the mathematical division signal above is as close as possible to the experimental one in terms of least squares. With the experimental division signal for a thickness of 1.67 mm (see FIG. 9 ), the following is obtained for a given DBR laser diode:
b 1 =3.57897, b 2 =0.022936, b 3 =4.81 10 −5 and b n =0 for n>3
Knowing the function g(t), the thickness of the glass to be measured can be determined by expression (17).
FIG. 11 shows the experimental results of a measurement taken across the width of a strip of float glass which was moving while the device of the invention travelled across its width. The abscissa shows the width of the strip, from 0 to 350 cm, and the ordinate shows the thickness in mm. The diamond points represent the measurements taken with a micrometer screw gauge. It can be seen that the precision of the measurement according to the invention is better since it is possible to interpolate between two manual measurements taken to one hundredth of a millimetre.
The invention thus makes it possible to monitor the thickness of the float glass during production with excellent precision. By virtue of the invention, it is also possible to take this measurement at high temperatures, that is to say before the glass enters the annealing lehr. The process controllers can then react to the production parameters straight away, which greatly limits waste and, in general, improves quality. | The invention relates to a process and to a device for measuring the thickness of transparent materials. More particularly, but not exclusively, the invention concerns the thickness measurement of glass materials and, even more precisely, the thickness measurement of flat glass, in particular float glass. According to the invention, a light beam with modulated frequency is focused, two light beams or rays reflected by each of the surfaces of the transparent material are received, interference is created between them, the number of oscillations per modulation period of the interference signal is determined, the path difference (δ) between the two beams and the thickness (e) of the transparent material are deduced and the phase shift (φ) of the said interference signal is determined. This determination of the phase-shift between the two signals each coming from one of the surfaces of the transparent material can then be used to deduce other characteristics of the said material. It may in particular be applied to the precise measurement of local thickness variations, in particular of a strip of float glass. Similarly, it is proposed to apply it to measuring the thickness of a thin transparent material, preferably more than 0.2 mm. | 6 |
This application is the national phase under 35 U.S.C. §371 of PCT International Application No. PCT/DE99/02876 which has an International filing date of Sep. 10, 1999, which designated the United States of America.
FIELD OF THE INVENTION
The invention relates to a method for measuring the rotation speed of an induction machine whose stator is connected via a controllable AC controller to a single-phase or polyphase AC power supply system. The invention also relates to a device for determining the rotation speed of an induction machine.
BACKGROUND OF THE INVENTION
It is known for controllable AC controllers to be used for matching the electric volt-amperes supplied to an induction machine to the respectively prevailing load conditions, in particular during starting and braking.
Such a microprocessor-controlled AC controller or soft starter, as is known for example from EP 0 454 697 B1, operates using the phase-gating principle and is used essentially for smooth starting and stopping of three-phase asynchronous machines. Three sets of active devices, in general each including two back-to-back connected thyristors, are generally actuated by a microprocessor for this purpose.
The control device in the known three-phase controller has no information about the present rotation speed of the machine. With certain mechanical load conditions, this can lead to poor operation of the overall drive. When stopping a pump drive, an abrupt drop in rotation speed can occur, which can lead to extremely high pressures in the pipeline system and thus to severe mechanical loads, and even to destruction of the system. A corresponding situation applies to the starting of drives when a sudden rise in the rotation speed occurs.
If the rotation speed is known, the control device, generally a microprocessor, can be used to provide rotation speed control which allows largely smooth starting and stopping of the drive, even when the mechanical load conditions are poor.
DE 27 15 935 A1 discloses a starting monitor for asynchronous machines, in which the phase angle between the current and voltage is determined. This is used to derive binary information about the starting of the machine. If starting does not take place within a specific time period, the machine is disconnected from the power system once again in order to avoid thermal overloads.
In U.S. Pat. No. 5,548,197A, the current zero crossings of the three stator currents are detected using, inter alia, the voltage which can be measured across the thyristors for this purpose. Two immediately successive current zero crossings are used to form an error signal by subtracting the times of the zero crossings from one another and then subtracting one-sixth of the power supply system period. The error signal, which fluctuates about the zero point, is subjected to frequency analysis, and the rotation speed of the rotor is determined from this. Power supply system disturbances can in this case result in corruption of the measurement signal.
A method which measures the polarity of the induced terminal voltage during the process of stopping an induction machine by means of a three-phase controller and which determines the rotation speed from the time difference between the polarity changes of the individual voltages is described in EP 0 512 372 B1. In any case, during the stopping process, there are time periods in which the induction machine is disconnected from the power supply system and in which, in consequence, no currents flow in the stator either. There is thus no need to interrupt the current supply solely to measure the rotation speed. In this case, in order to brake the induction machine, specific trigger sequences of thyristors are defined in advance, and the time offset of the respective polarity change is evaluated as the frequency for determining the rotation speed. On the other hand, no method is specified for general starting and stopping.
U.S. Pat. No. 5,644,205A and DE 195 03 658 C3 each indicate a method for measuring the rotor angular velocity for machines using frequency-changing control. These methods use the frequency of the induced voltage once the power supply has been disconnected from the machine to determine the rotor angular velocity. Owing to the considerably different functional principles of frequency changers and three-phase controllers, the method of producing a stator without current, which is known from the cited documents, cannot be transferred to machines controlled by three-phase controllers.
SUMMARY OF THE INVENTION
Against the background of the prior art, the invention is now based on the object of specifying a method for measuring the rotation speed of an induction machine, which can be carried out easily during acceleration during the starting of the induction machine and in which there is no need for any additional measured value sensors for detecting the rotation speed. Furthermore, the invention is based on the object of specifying a device for controlling such an induction machine.
According to the invention, the first-mentioned object is achieved by a method for measuring rotation speed of an induction machine whose stator is connected, via a controllable AC controller having active device arrangements, to an AC power supply. The method includes controlling the active device arrangements to disconnect the stator from the AC power supply system for at least one predetermined time period (Δt), which is less than half of a period (T) of a voltage of the AC power supply system, by controlling the active device arrangements; measuring in the time period (Δt), a voltage which is induced in the stator by rotary movement of a rotor and using the measured voltage to determine components of a stator voltage space vector; and determining a rotation frequency of the stator voltage space vector from the measured voltage, and deriving the rotation speed of the induction machine therefrom. In the method for measuring the rotation speed of an induction machine whose stator is connected via a controllable AC controller to a single-phase or polyphase AC power supply system, the stator is disconnected from the AC power supply system for at least a predetermined time period by controlling the active devices in the AC controller. At least one stator voltage, which is induced in the stator by the rotary movement of the rotor, is measured in this time period. The measured values obtained in this way are used to determine the frequency of this stator voltage, and the rotation speed of the induction machine is derived from this.
The stator is thus temporarily placed in a situation where no current is flowing during acceleration of the induction machine. During the time period in which no stator current is flowing, a slowly decaying direct current flows in the rotor. As a result of this, the rotor can be regarded as a rotating magnet with virtually constant magnetic flux, with respect to the rotor coordinate system. The rotation induces voltages (terminal voltages) across the stator terminals of the induction machine, whose frequency corresponds to the product of the known number of pole pairs p and the mechanical rotation speed to be measured.
According to the invention, the rotation speed of the rotor is detected using the frequency of the stator voltage space vector, which can be determined on the basis of the induced voltage, during a time period which is produced deliberately with the aid of the controllable AC controller and in which no current flows in the stator. According to the invention, the time duration of this time period is shorter than the time duration of half the period of the power supply system voltage, in order to influence the operation of the drive only to a minor extent.
For the same reasons, in a further preferred refinement of the invention, the rotation speed measurement in accordance with the abovementioned method is repeated after specific time periods, which are preferably 5 to 15 times the period of the power supply system voltage.
Thyristors are preferably used as the active device arrangements, and the induction machine is disconnected from the AC power supply system by omitting the trigger signals required to trigger the thyristors.
In one particularly preferred refinement of the invention, in order to resume the power supply system operation of the induction machine in the case of a three-phase induction machine, the first trigger signal for the first-opened first active device arrangement in one phase is delayed by a multiple of half the power supply system period with respect to the last trigger signal for this first active device arrangement. At the same time as the renewed triggering of this first active device arrangement, a second active device arrangement is triggered, which is an active device arrangement that is triggered subsequently in normal operation. The third active device arrangement is triggered one-sixth of the power supply system period after the triggering of the first active device arrangement, with the trigger signal sequence which was present before the disconnection then being reproduced. This measure ensures that the interruption in the voltage supply to the induction machine which follows the rotation speed measurement has as little influence as possible on the continued operation of the induction machine.
In a further advantageous refinement of the method, during the time period during which no current is flowing in the stator in the case of a polyphase AC power supply system, the terminal voltages which are in each case induced in the stator windings between the stator terminals are measured. The angle of the space vector of the induced stator voltage is in each case calculated, in particular, from the measured values of the terminal voltage.
For discrete-time sampling of the induced terminal voltage, the clock rate is in this case defined such that the associated angles of the space vector of the induced stator voltage are calculated for as many times as possible within the time period. The determined angles of the space vector are associated, within the time period during which no current is flowing in the stator, with a straight line from whose gradient the rotation speed of the induction machine is determined.
According to the invention, the second-mentioned object is achieved by a device for determining rotation speed of an induction machine whose stator is connected via an AC controller to an AC power supply system. The device includes a control device for controlling the AC controller, and for disconnecting the stator from the AC power supply system for a predetermined time period (Δt), which is shorter than half a period (T) of a voltage of the AC power supply system, by controlling active device arrangements of the AC controller; a voltage measurement device for measuring at least one terminal voltage which is induced in the stator by rotary movement of a rotor in the time period (Δt); and a computation device for calculating a frequency of the measured terminal voltage and for calculating the rotation speed of the induction machine from the calculated frequency, wherein a control signal for the control device is present at one output of the computation device, the control signal being derived from the rotation speed and being passed to the control device. The device for controlling an induction machine, whose stator is connected via an AC controller to a single-phase or polyphase AC power supply system, contains a control device for controlling the AC controller and for disconnecting the stator from the AC power supply system for a predetermined time period by opening the active device arrangements in the AC controller. It further includes a voltage measurement device for measuring at least one stator voltage which is induced in the stator by the rotary movement of the rotor in this time period. Finally, a computation device is included, for calculating the frequency of this stator voltage from the measured values obtained in this way, and for calculating the rotation speed of the induction machine from this frequency.
In one preferred embodiment, the rotation speed is used to derive a control signal for the control device. This control signal is produced at one output of the computation device and is passed via a control line to the control device.
Further preferred embodiments of the device are evident from the subsequent description of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to explain the invention further, reference is made to the exemplary embodiment in the drawing, in which:
FIG. 1 shows a device according to the invention for controlling a three-phase induction machine, illustrated in the form of a schematic block diagram.
FIG. 2 shows the currents flowing in the stator windings, plotted in the form of a graph with respect to time.
FIG. 3 shows the terminal voltages measured between each of the terminals of the stator, likewise plotted in the form of a graph with respect to time.
FIG. 4 shows the time profile of the angle of the space vector of the induced voltage, likewise in the form of a graph.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
According to FIG. 1, an induction machine 2 , in the example of a three-phase asynchronous machine, is connected via a three-phase AC controller 4 (three-phase controller) to the phases L 1 , L 2 , L 3 of a three-phase power supply system. Each phase L 1 , L 2 , L 3 has an associated active device arrangement V 1 , V 2 , V 3 which, in the exemplary embodiment as shown in FIG. 1, each include two back-to-back parallel connected thyristors 6 . The triggering electrodes of the thyristors 6 are connected to a control device 8 , which produces the trigger signals required to trigger the thyristors 6 , in a predetermined time sequence.
A voltage measurement device 10 is connected between each of the stator terminals K 1 , K 2 , K 3 of the induction machine 2 , at whose output the terminal voltages u K12 , u K23 , u K31 which occur in each case between the relevant two stator terminals K 1 , K 2 , K 3 are produced. As an alternative to this, the voltages between a stator terminal K 1 , K 2 , K 3 and a neutral conductor, which is not shown in the figure, can also in each case be measured and used to derive the terminal voltages u K12 , u K23 , u K31 .
The outputs of the voltage measurement devices 10 are connected to a computation device 12 in which the analog voltage signals u K12 , u K23 , u K31 , which are, for example, present continuously at the input, are processed further. The computation device 12 contains a first computation unit 14 in which the terminal voltages u K12 , u K23 , u K31 , which are present in the form of analog measured value signals, are subjected to a coordinate transformation in the process of which the components u sx and u sy of the space vector u s < of the induced stator voltage and, from this, the angle γ of the space vector u s < of this stator voltage, are calculated. The values obtained in this way for the angle γ of the space vector u s < are written continuously to a memory 16 .
The memory 16 is followed by a second computation unit 18 , in which the angles γ stored in the memory 16 are read and are used to calculate the rotation speed n of the induction machine 2 . The values for the angle γ written to the memory 16 are in this case processed further in the second computation unit 18 only in a time period in which it is certain that there is no current flowing in the stator of the induction machine 2 . The read process and computation process in the second computation unit 18 are in this case initialized by the control device 8 , in which the program routine for the measurement sequence is stored. A control signal which corresponds to the rotation speed n is produced at the output of the computation device 12 and is passed to one input of the control device 8 , where it is evaluated in order to control the induction machine 2 .
The second computation unit 18 is thus initialized only in a time period in which it is certain that no stator currents i 1 , i 2 , i 3 are flowing in the phases L 1 , L 2 , L 3 .
In the graph in FIG. 2, it can be seen that no current is flowing in the stator of the induction machine in a time period Δt. Thus, all the stator currents i 1 , i 2 , i 3 are equal to zero in this time period Δt.
The situation where no current flows in the stator is now produced first of all by not passing any trigger pulses to the thyristors 6 (FIG. 1 ). This leads to initial extinguishing of the current in one of the three stator windings, in the example the current i 3 in the phase L 3 at the time to (initial extinguishing phase). The currents i 1 , i 2 in the two remaining windings or phases L 1 , L 2 are then extinguished at the time t 1 , so that no current is flowing in the stator in the time period Δt between t 1 and t 2 , and the evaluation of the terminal voltage u K12 , u K23 , u K31 can start.
The stator voltage induced at the terminals of the electrical machine, in the stator coordinate system and when no current is flowing in the stator, is given by: u s ∠ = L h · t ( i R ∠ · j · ϒ ) u s ∠ - space vector of the stator voltage L h - main inductance of the machine i R ∠ - space vector of the rotor current γ - rotation angle of the rotor current space vector with respect to the stator coordinate system
The following expression is obtained by differentiation: u s ∠ = L h · ( j · ϒ · i R ∠ t + j · ω · j · ϒ · i R ∠ )
ω - Electrical angular velocity of the rotor , where ω = γ t
Since the rate of change of the decaying rotor direct current is negligibly small in comparison to the change resulting from the rotation, the first summand in the bracket in the above equation can be ignored, resulting in:
u
s
<
≡j·L
h
·ω·e
j·γ
·i
R
<
It follows from this that the angle between the stator voltage space vector u s < and the rotor current space vector i R < related to the stator is constant, and that the frequency of the induced terminal voltage u K12 , u K23 , u K31 corresponds to the electrical angular velocity of the rotor. FIG. 3 shows the waveform of the terminal voltages u K12 , u K23 , u K31 .
The position of the stator voltage space vector u s < is now determined from the three measured terminal voltages u K12 , u K23 , u K31 by means of a coordinate transformation, which is known per se: u s ∠ = u SX + j · u SY = ( 2 3 · u K12 - 1 3 · u K23 - 1 3 ) + j · ( 1 3 · u K23 - 1 3 · u K31 ) u SX - x - component of the stator voltage space vector u s ∠ u SY - y - component of the stator voltage space vector u s ∠ u K12 , u K23 , u K31 - voltages which can be measured between the stator terminals K1 , K2 and K3
The physical orientation (angle) γ of the stator voltage space vector u s < is obtained from the known relationship: γ = arg ( u s ∠ ) = arctan ( u SY U SX )
A number of measured values of the physical position of the stator voltage space vector u s 2 are obtained by determining the terminal voltages u K12 , u K23 , u K31 and calculating the angle γ within the time period Δt within which no current is flowing in the stator, a number of times. These measured values are shown plotted with respect to time in the graph in FIG. 4 . Ideally, at a constant speed, these values produce a straight line G, whose gradient α corresponds directly to the sought electrical angular velocity ω of the rotor.
In order to obtain a reliable measured value for the electrical rotor angular velocity and to minimize the influence of measurement errors, the gradient is determined with the aid of a comparison straight line, which can be obtained from the recorded angle values by appropriate mathematical methods, preferably by minimizing the squares of the errors.
The mechanical rotor angular velocity is now obtained from the electrical rotor angular velocity simply by dividing by the known number of pole pairs p in the induction machine.
In order to keep the influence on the drive of the time period during which no current is flowing low, the sets of active devices must be retriggered such that the torque and stator currents respond approximately as if no rotation speed measurement had been carried out.
According to FIG. 2, this can be done by increasing the triggering time t 3 of the last triggering (but which was not carried out) of the initially extinguishing active device arrangement V 3 by half the power supply system period T (=180°) and placing it at the time t 2 =t 3 +T/2. In order to obtain a stator current flow after this retriggering, the retriggering of the active device arrangement V 1 which follows the initially extinguishing active device arrangement V 3 in the power supply system rotation direction also being placed at the triggering time t 2 which results from this. When the current flow starts in response to the first retriggering, the actual rotation speed measurement is terminated, since the induced terminal voltages are once again governed by the stator current flowing and thus do not include any measurement signal containing the rotor angular velocity.
Thus, depending on the type of electrical machine and the load conditions, approximately one-third of a power supply system period is available for the rotation speed measurement. This is completely sufficient for the described method.
The remaining active device arrangement V 2 is triggered with a delay of one-sixth of the power supply system period (=60°) with respect to the initially extinguishing active device set at the time t 4 , resulting in the recreation of the normal cycle of active device triggering processes.
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. | In order to measure the rotation speed of an induction machine whose stator is connected via a controllable AC controller to a single-phase or polyphase AC power supply system, the stator is disconnected from the AC power supply system for at least a predetermined time period (Δt). This is preferably achieved by opening active devices in the AC controller, with at least one stator voltage, which is induced in the stator by the rotary movement of the rotor, being measured in this time period (Δt). The measured values are used to determine the frequency of the stator voltage and to derive the rotation speed of the induction machine. | 7 |
This application is a continuation-in-part of U.S. patent application Ser. No. 08/518,020, filed Aug. 22, 1995, now U.S. Pat. No. 5,611,845.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a novel method and apparatus for life support systems for supplying a pressurized diver's breathing gas for underwater divers and, more particularly, to a subassembly equipment package useable by dive shops, remote sites, diver boats, live aboards and the like for incorporation into the novel apparatus of the present invention whereby an advantageous life support system for supplying diver's breathing gas can be readily produced.
2. Description of Related Art
Techniques for producing a mixture of oxygen enriched air, known in the art as EAN x (enriched air nitrox), have been known for many years, as well as the advantages of using such enriched air as a diver's breathing gas. However, the life support systems for producing same have utilized the concept of enriching air by adding pure oxygen to it. Such a system is disclosed by U.S. Pat. No. 4,860,803 to Wells, which shows oxygen injected into a stream of ambient air in order to produce an oxygen enriched air mixture. The mixture is compressed and delivered to storage or scuba cylinders for use in diving or other applications. A source of oxygen appropriate for injection into the ambient air stream is needed in this known system and, consequently, not only is a great deal of caution required during generation of the oxygen enriched air mixture to avoid explosions and other problems typically associated with the use of oxygen, but, even more important, such systems require oxygen cleaning which is a drawback.
SUMMARY OF THE INVENTION
Accordingly, it is a principal object of the present invention to provide a method and apparatus for life support systems for supplying or producing a diver's breathing gas, DNA x , that avoids the problems and drawbacks of the prior art and functions in a more efficacious and versatile manner.
It is a further object of this invention to provide an improved life support system for enhancing the oxygen content of air to generate a pressurized enhanced oxygen air mixture suitable for a diver's breathing purposes, which does not require the use of oxygen supplied from a separate oxygen source. The DNA x (Denitrogenated Air Nitrox) is produced by an enhancement technique as opposed to an enrichment technique.
It is another object of this invention to provide such a life support system in a convenient equipment package which is easily transportable and can be installed together with other on-site equipment to create the apparatus and method of the present invention in a dive shop, diver's boat, remote site and other such locations.
According to the present invention, these and other objects are accomplished by the provision of a unique equipment package that includes a special permeable membrane gas separation system, such as the one supplied by PERMEA, INC. of St. Louis, Mo. and sold under the trade name PRISM Membrane System. The PERMEA, INC. PRISM Alpha Membrane System uses thousands of membrane fibers each having an axially through lumen that are bundled into and appropriately sealed in a cylinder. Air is introduced axially into one end of the cylinder and oxygen and a portion of the nitrogen permeate through the fibers and are drawn off through a radial outlet that communicates with the annular space surrounding the fibers. Nitrogen passes axially through the fibers and is discharged axially at the other end of the cylinder. This membrane system is disclosed in U.S. Pat. No. 4,894,068 which is incorporated herein by reference. Other similar membrane systems using bundles of hollow fibers are shown, e.g., in U.S. Pat. No. 5,226,931.
The package also includes an entry conduit for higher pressure air provided with an on-off valve that leads to a thermostatically controlled heat exchanger via a pressure regulator that expands the air with cooling to a lower pressure, i.e., a corresponding drop in temperature and pressure. The discharge of the lower pressure, temperature controlled air of the heat exchanger is passed through a carbon filter, and into one end of the membrane gas separation system cylinder. As noted, nitrogen is discharged from the other end of the cylinder and the discharge is controlled by a manually or automatically controllable needle valve.
The enhanced oxygen air (DNA x ), sometimes referred to herein simply as Nitrox, is discharged radially from the cylinder through a low pressure conduit and monitored by a low pressure oxygen analyzer. This equipment package is connected at the utilization site with a high pressure compressor driven by a suitable prime mover via an overpressure valve set at a predetermined value above the design pressure in the low pressure conduit. The high pressure Nitrox (DNA x ) is filtered in a known CGA Grade E filtration system. The output of the filtration system is distributed by appropriate valving to either a high pressure compressed DNA x storage cylinder or to a fill station provided with a pressure gauge and a high pressure oxygen analyzer. Also, a high pressure compressed air storage cylinder serving as a supply to the equipment package is, by appropriate valving, also available to the fill station.
As noted, the package includes a pressure regulator for reducing a feed air pressure of from 175-6000 p.s.i.g. to a pressure in a range of 50-400 p.s.i.g. Depending upon the characteristics of the gas separation membrane system, the heat exchanger will adjust the feed air temperature to the design temperature of the membrane by either heating or cooling the feed air after reduction of the high pressure feed air to a low pressure. This pressure reduction selectively produces a cooling effect. The oxygen content of the DNA x discharged from the package is controllable by adjusting the reduced pressure or temperature of the feed air into the gas separation membrane system. The preferred way, however, is to adjust the rate of discharge of the nitrogen from the membrane system, and, to this end, an adjustable valve, preferably a needle valve, is placed in the nitrogen discharge line. Manipulation of the needle valve controls the nitrogen discharge flow rate, which, in turn, controls the oxygen concentration of the enhanced oxygen air, (DNA x ), passing from the package. The nitrogen flow rate is directly proportional to the oxygen content, i.e., a greater flow rate produces a greater oxygen content at the DNA x outlet.
In other systems according to the invention, the feed air to the pressure regulator can be obtained from a low pressure compressor, optionally via a volume tank. In this case, the output of the low pressure compressor is feed air at 50-175 p.s.i.g. Also, the DNA x discharging from the gas membrane separation system can be fed, via a suitable overpressure (relief) valve to a low pressure compressor and then to a DNA x storage or volume tank via filters. The output from the DNA x volume tank can be used directly by an underwater working diver with a full face mask connected by a breathing tube and flow control valve to the DNA x volume tank.
Other and further objects and advantages of the present invention will become more apparent and evident from the following description of a preferred embodiment and best mode when taken in conjunction with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view in side elevation showing the novel subassembly equipment package of the invention.
FIG. 2 is a block diagram of a novel embodiment of the method and apparatus according to the present invention.
FIG. 3 is a view in side elevation showing a novel oxygen sensor as used in the equipment package of FIG. 1.
FIG. 4 is a view in axial section of a fitting used with the oxygen sensor of FIG. 3.
FIG. 5 is a block diagram showing another novel embodiment of the method and apparatus according to the present invention.
FIG. 6 is a block diagram showing still another novel embodiment of the method and apparatus according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIG. 2, a novel embodiment of the apparatus and method according to the present invention is shown and consists of an equipment package 10 (a subassembly) that receives high pressure, compressed air from compressed air tank 12 via line 14 and valve 16. Nitrogen is discharged or exhausted from package 10 via line 18 and valve 20. Nitrox, enhanced oxygen air (DNA x ) is discharged or exhausted from package 10 via line 22 and overpressure valve 24, and is connected to the inlet of a high pressure compressor 26 driven by a suitable prime mover (not shown). The high pressure compressed DNA x passes through filter 28 and exhausts through line 30 via valves 32 and 34 to a high pressure compressed DNA x storage cylinder 36. Branch line 38 connects line 30 to a DNA x fill station 42 via valve 40. Fill station 42 is provided with a high pressure gauge 44 and a high pressure oxygen analyzer 46. Scuba tanks 48 (only one shown) are filled at the fill station 42 via line 50 and control valve 52. High pressure DNA x from storage cylinder 36 can pass to the fill station via line 30, branch line 54 and valve 56 coupled to branch line 38. Compressed air from cylinder 12 can pass to the fill station 42 via branch line 58 and valve 60, if it is desired to fill tanks with compressed air.
Reverting now to FIG. 1, line 14 from tank 12 couples to package 10 via line 100, which may be simply a continuation of line 14. An on-off valve 102 is coupled to line 100 to control the flow rate.
The high pressure feed air from tank 12 supplied through the air inlet line 100 is at a pressure of from 175-6000 p.s.i.g. but preferably from 1000 to 4500 p.s.i.g. Line 101 connects valve 102 to a pressure regulator 104 controlled, by operation of a rotatable knob 106, to adjust or reduce the pressure of the high pressure feed air supplied through the inlet line 100 to a low pressure of from about 50 to about 400 p.s.i.g., but preferably from 100-300 p.s.i.g. which is the preferred range. A first gauge 108 provides a high pressure inlet reading, in p.s.i.g., and a second gauge 110 provides a reduced pressure reading for the low pressure feed air exiting the pressure regulator. The reduction in pressure through valve 104 selectively produces a cooling of the low pressure feed air depending upon the selected pressure drop.
Low pressure cooled feed air exits the pressure regulator 104 and is introduced via tube 112 axially into an elongated copper tube 114 about 2-21/2 inches in diameter serving as a heat exchanger. The low pressure air passes axially down the tube 114 which is appropriately baffled to first lead the air down and then up to a radial discharge port near the top of tube 114, which port is connected with line 116. Tube 114 is jacketed with insulation 118 throughout most of its length (about 95%) and is provided with resistance heating bands 120 axially spaced on tube 114. A pair of wires 122 carry electricity to bands 120 from a manually controllable thermostat 124, controlled by knob 126. An electric power cord 134 supplies power via thermostat 124 to the resistance heating bands 120. Alternatively, the heating of the air can be effected by a resistance coil positioned axially in tube 114 with wires 122 connected through the wall of tube 114 in an insulated and gas tight manner. The air is heated to from about 80° F. to about 150° F. and preferably in the range of from about 90° F. to about 125°.
Low pressure air is discharged from tube 114 through line 116 which connects into a carbon filter 128 designed to remove hydrocarbons. A thermocouple 130 is mounted on filter 128 and is exposed to the air passing therethrough. The output of thermocouple 130, which senses the air temperature, is connected to the thermostat 124, via leads 132. The heated low pressure air exhausting or discharging from filter 128 is led by line 136 to the top of a gas separation membrane system in the form of an elongated plastic (PVC) tube 140 having aluminum end caps 142, 144 at its ends.
The gas separation membrane system shown in FIG. 1 consists of a bundle of hollow fibers contained in the tube 140 and this system is sold by Permea, Inc. under the trade name PRISM Alpha Membrane Separator. The fibers are sealed together at their ends and sealed in the tube 140 spaced slightly from caps 142, 144. Entry into the tube 140 of low pressure heated air is axially at one end with discharge of nitrogen being axially at the other end. Since oxygen migrates through the walls of the hollow fibers faster than nitrogen, the oxygen and some nitrogen is collected in the annular space surrounding the hollow fibers. The nitrogen that traverses the hollow fibers collects at the other end. Nitrogen, containing less than about four percent oxygen, passes out of tube 140 through line 146 having a manually or automatically adjustable needle valve 148 interposed therein to control the flow rate. The nitrogen exhausting from line 146 is a waste gas and couples with line 18 of FIG. 2 to lead the nitrogen to a location where it can be dispersed in the ambient without danger to life due to suffocation or oxygen deprivation.
Tube 140 is jacketed with insulation 150 extending coextensive with jacket 118 of tube 114. A temperature gauge 190 is tapped into line 136 where it connects into the center of cap 142 to provide a visual reading of the temperature of the low pressure heated air as it enters the gas separation membrane system.
The DNA x that collects in the annular space in tube 140 is withdrawn through radial port 152 defined or formed in the wall of tube 140 and passes into a plastic tube 154, one end of which contains an enlarged cross section 156 within which is mounted a one-way check valve consisting of valve seat 158, stemmed valve element 160 and a spring 162 biasing the element 160 against seat 158 with a force of about 1-3 p.s.i, but preferably 0.5 p.s.i. The end of tube 154 is closed by a porous resilient filter 164, such as plastic foam, to filter ambient air entering tube 154 against the force of the one-way check valve. The other end of the tube 154 is connected to corrugated tube 166 which couples to or is simply a continuation of line 22 of FIG. 2. A nipple or projection 168 containing a monitoring orifice is mounted on the tube 154 adjacent to radial port 152, on its downstream side, that is, toward tube 166. The orifice is exposed to the interior of tube 154 and, therefore, a small quantity of DNA x will flow through the orifice. A tube 170 friction fits into projection 168 and couples the downstream side of the orifice and projection 168 to the inlet 172 of a low pressure, temperature compensated, oxygen sensor 174. Sensor 174 consists of a housing into which a fitting 176 is received in a gas tight fashion which is coupled to tube 170 and provides an exhaust port 178. Also, mounted on the housing of sensor 174 is an on-off contact switch 180, a digital display 184, a calibration knob 182 to "zero" or set the digital display 184 to ambient O 2 conditions, and, within the sensor 174, an oxygen sensor, a battery, appropriate electronics, as known, and leads connecting all components.
A pair of rails 200 are provided for mounting the components of the package. Rails 200 are U shaped channel sections of extruded aluminum having plastic end caps 202. The open mouth of the rails 200 faces horizontally and is slightly closed or narrowed by inwardly directed flanges 204. Clamps, in the form of bent bars 206 of aluminum, are notched to be received in rails 200 and engaged with flanges 204 and extend around tubes 140 and 114, defining bent flanges 208 that are coupled by nut and bolt assemblies 210. Thermostat 124 is attached to the top of top rail 200 as viewed in FIG. 1 by a conventional attachment. Tube 146 can be brought to either rail with needle valve 148 being clamped to the rail by a conventional clamping means. Tube 170 is received in projection 168 in a friction fit that provides a substantially gas tight coupling while being removable from projection 168 simply by pulling out. Tube 170 can be reinserted into projection 168 simply by pushing in. The reason for this is that the oxygen sensor 174 is delicate and needs to be handled separately from the remainder of the package when it is being moved about, such as when installed. In the manner described, sensor 174 and tube 170 can be readily decoupled.
The high pressure compressed air in tank 12 is at a pressure of from about 175-1000 as a minimum to about 6000 p.s.i.g. and preferably from about 1000 to about 4500 p.s.i.g. Regulator valve 104 regulates the feed air from high pressure of tank 12 by expanding the high pressure compressed air and dropping the pressure into the low pressure range of from about 50 to about 400 p.s.i.g., and, preferably, from about 100 to about 300 p.s.i.g. When the high pressure is dropped to the low pressure, considerable cooling is effected. Heater 114 adjusts the temperature of the low pressure air to from about 90° F. to about 125° F. This combination of pressure and temperature optimizes the efficiency of the Permea Gas Separation Membrane System, which is the preferred membrane system. The pressure of the DNA x exiting the port 152 is from about 0.5 to 5 p.s.i.g., the preferred range is from about 1 to about 2.5 p.s.i.g., and the best operating condition is from 1 to 2 p.s.i.g. The monitoring orifice in projection 168 meters the DNA x at the rate of from about 0.25 liters per minute to about 0.5 liters per minute when the pressure at the exit port 152 is from about 1 to about 2 p.s.i.g. and, to insure control, a pressure gauge 240 is tapped into tube 154 in the immediate vicinity of port 152. The pressure, temperature and other operating conditions including flow rate of the package are adjustably controlled to achieve the exit pressure at port 152 of from about 1 to about 2 p.s.i.g.
The one-way check valve in tube 154 serves as a safety for the compressor 26 when the package is connected into the system of FIG. 2. The valve element 160 is biased by spring 162 to open at 0.5 p.s.i.g. to admit ambient air when a negative pressure is in tube 154. Filter 164 is a porous resilient plastic foam mass and serves to keep out dust, dirt and other foreign matter. When compressor 26 is started and insufficient DNA x is exhausting through port 152, and when the pressure in tube 154 is less than ambient by 0.5 p.s.i.g. or more, the one-way check valve will open and admit ambient air to insure a proper compressor loading. The one-way check valve will close when the DNA x pressure in tube 154 is equal to or greater than ambient pressure (atmospheric).
The output pressure of the compressor 26 is from about 600 p.s.i.g. to about 4500 p.s.i.g. but could be higher depending on the rating of the tank 36 and scuba tank 48. Also, overpressure valve 24 is set at 0.5-4 p.s.i. above the pressure of the DNA x in line 22 which is the same as exiting port 152. The heat setting for valve 24 is 2.8 p.s.i. The enhanced oxygen content of the DNA x exiting through port 152 is adjustably controlled by changing the operating conditions of the package, i.e., by controlling pressure, temperature and flow rate. The best mode contemplated for controlling oxygen content of the DNA x is to manually adjust the exhaust flow rate of the nitrogen in line 146 by manually and selectively adjusting the position of needle valve 148 while visually monitoring the digital display of oxygen sensor 174. There is a slight time delay in the procedure, so adjustment of the needle valve 148 needs to be effected stepwise with small delays to allow the system to equilibrate, i.e., come to equilibrium. The preferred oxygen concentrations in the DNA x are 32%, 36% and 40% although others may be selected.
Referring now to FIGS. 3 and 4, a novel low pressure, temperature compensated, oxygen sensor 300 is shown. This sensor is used for sensor 174 in the equipment package of FIG. 1. As shown, sensor 300 is a box-like structure or housing consisting of a bottom part 302 and a top part 304 joined together by hinge member 306 consisting of a pair of spaced ears 308 attached to top part 304, a projection 310 attached to the bottom part 302 which fits between the ears 308 and a hinge pin 312 holding the ears 308 and projection 310 together in a relatively rotatable relationship. The joint 322 between the bottom and top parts is on an oblique line extending downwardly from the hinge member 306. A projection 314 in the form of an ear is attached to the top surface of top part 304 and an endless cord 318 is looped through hole 316 formed in projection 314. Bead 320 is slidably carried by the cord 318 to adjust the loop in contact with ear 314.
A clamp member 324, consisting of mutually engaging hook elements, the outer one 326 of which is pivoted to a support plate 325 mounted on bottom part 302 by a pivot pin 328, and the inner one being a hook 327 formed on top part 304, serves to effect closure of top part 304 to bottom part 302. The joint between the top and bottom parts 304, 302 is flanged or thickened as indicated by reference numeral 330 and one flange is provided with an endless groove or depression for receiving a gasket or sealing ring. When the parts are pivotally brought together and clamped by clamp member 324, the gasket is compressed and a substantially liquid tight seal is effected.
A bore 334 is formed through the front wall of bottom part 302 with an annular plug 336 fitted and sealed into bore 334 and having a slightly elevated inner annular rim 338 immediately surrounding the bore 334. A digital display 340, e.g., an LED, is located on the front wall or face of the bottom part 302 below plug 336. A contact on-off switch 342 slightly projects from the side wall of bottom part 302 opposite clamp member 324. A rotatably mounted calibration knob 344 is mounted on the top wall of top part 304.
A feed plug 350 is shown in axial section in FIG. 4, which is received in the bore 334. The function of feed plug 350 is to connect with line 170 of FIG. 1 and to bring the metered DNA x into the bore 334 where it is contacted with the oxygen sensor 354 mounted in bottom part 302 on the inside of the wall surrounding the bore 334 in a gas tight manner. Plug 350 consists of an outer cylinder 360 of plastic and an integral inner cylinder 362 of plastic having a reduced section so that the cylinders define between them a shoulder 364. An axial bore 366 extends from the free end of cylinder 362 back into cylinder 360 and terminates spaced from the free end of cylinder 360. A metal tube 368 is radially received in cylinder 360 and extends into bore 366 where it is bent 90° at 370 to then be directed axially through the bore to terminate at the free end of cylinder 362. A plastic sleeve 372 is fitted over the radially projecting end of tube 368 to facilitate coupling to tube 170. An annular space 374 is defined between the axial extension of tube 368 and the wall of bore 366. A radial bore 376 in cylinder 360 communicates space 374 with the ambient. The outer peripheral surface of cylinder 362 substantially midway between shoulder 364 and the free end of cylinder 362 defines a peripheral groove 378 extending in a plane normal to the axis of cylinder 362. An O-ring seal 380 is received in groove 378. A second O-ring seal 382, of smaller diameter, is received on the periphery of cylinder 362 and sits at the junction of shoulder 364.
The plug 350 is received in the bore 334 with cylinder 362 projecting into bore 334 and with the free end of cylinder 362 lying in close proximity with oxygen sensor 354. DNA x metered into tube 170 passes into metal tube 368 and is exhausted from the other end of tube 368 at the free end of cylinder 362 in close proximity to oxygen sensor 354. DNA x leaving tube 368 eventually passes back through annular space 374 and bore 376 to be exhausted to the ambient. Cylinder 362 force fits into bore 334 and O-ring 380 bears against the wall of annular plug 336 defining bore 334 to effect a gas tight seal. O-ring 382 bears against raised rim 338 to reinforce the gas tight seal.
The electronics of the oxygen sensor are contained on a board 390 mounted in the lower region of the inside wall of the bottom part 302. A power supply in the form of a battery 392 is wedged on opposite sides by foam plastic pieces 394 into the inside of the top part 304. Electric leads 396, 398, 400 and 402 connect calibration knob 344, battery 392, on-off contact switch 342 and temperature compensated oxygen sensor 354, respectively, to the circuit board 390. The electronics of the circuit board 390 are known in the art.
The life support embodiment shown in FIG. 5 consists of a low pressure compressor 400 receiving ambient air as an inlet via line 402. The output from compressor 400 (from about 50-about 175 p.s.i.g.) is directed by line 404 to volume tank 406, line 408 to grade E filters 410 and by line 412 to pressure regulator valve 414 which reduces the pressure to >50 to <175 p.s.i.g. with some cooling. The cooled expanded feed air passes by line 416 to gas separation membrane system 420 as previously described. A temperature gauge 418 monitors and displays the temperature. The nitrogen discharge from system 420 passes via line 422 in which manually or automatically controllable needle valve 424 is interposed.
The DNA x discharged from membrane system 420 passes by line 426 through an overpressure valve 428 to a high pressure compressor 430. The output of compressor 430, compressed air at from about 600-4500 or greater p.s.i.g. passes to high pressure, grade E filters 432 via line 434. A low pressure oxygen sensor 440 monitors line 426. Ambient air can be drawn into line 426 through a check valve 436 via line 438 as previously described. The output of filters 432 is fed by line 442 to storage tank 444 for storing high pressure DNA x . A fill station 446 provided with a temperature gauge 448, a high pressure oxygen sensor 450 and a fill valve 452 is connected to tank 444 by line 454. Branch line 456 with on-off valve 458 provides a bypass to tank 444, e.g., if it is desired to go directly to fill station 446 or provide other utilization of the high pressure DNA x .
The life support embodiment of FIG. 6 consists of an ambient air line 500 input to low pressure compressor 502 which outputs via line 504 to volume tank 506, line 508, grade E filters 510 and line 512 to pressure regulator 514. Line 516 with temperature gauge 518 leads to membrane system 520. Nitrogen discharge is via line 522 and needle valve 524. DNA x discharge is via line 526 which is monitored by low pressure oxygen sensor 528 and into which line 530 connects to allow ambient air to be drawn in via check valve 532. An overpressure valve 534 is interposed in line 526. To this point the components and parameters are the same as described in FIG. 5.
A low pressure compressor 540 receives the output of line 526 and outputs a compressed DNA x having a pressure from about 50-about 175 p.s.i.g. which passes via line 542 to low pressure grade E filters 544 and line 546 and then to storage tank 548 for low pressure DNA x . Line 550 connects tank 548 through a flow regulator 552 with a flexible breathing tube 554 leading to a full face mask 556 on a diver 558 working or swimming under the surface 560 of a body of water 562. Bypass branch line 564 connects to line 546 and has a control valve 566 interposed therein.
Although the foregoing description has been with reference to a vertical orientation for the equipment package illustrated in FIG. 1, the orientation can be horizontal or at any angle. Also, the gas separation membrane systems of the type used by the method and apparatus of the invention, namely, a bundle of hollow fibers, operate within the temperature ranges stated in the foregoing except in one case. In this case, the operating temperature ranges from about 35° F. to about 50° F. When this membrane system is used in the invention, the heat exchanger of the equipment package will cool or heat as necessary to adjust the low pressure feed air to the appropriate operating temperature for the membrane system.
Although the invention has been described herein by reference to a preferred embodiment, nevertheless, changes and modifications are possible as will be evident to those skilled in this art. Such changes and modifications which do not depart from the spirit, scope and teachings are deemed to fall within the purview of the appended claims. | A system that includes an equipment package for separating nitrogen from air to produce enhanced oxygen air for use by divers. The package is combined with a pressure storage tank for air that is coupled to the package. A pressure storage tank is provided for enhanced oxygen air. A fill station including a high pressure gauge and a high pressure oxygen sensor is provided to fill divers' tanks. A compressor receives the enhanced oxygen air from the package and delivers high or low pressure enhanced oxygen air to the pressure storage tank via a pressure filter. Valving is provided for selectively controlling the flow in the system. | 2 |
BACKGROUND
[0001] The present disclosure relates to a chemical composition for semiconductor cleaning processes, and more particularly, for a post chemical mechanical planarization (CMP) cleaning, which can be used in advanced semiconductor fabrication and packaging.
[0002] Post CMP cleaning is perhaps one of the most critical steps in reliability improvement for semiconductor fabrication and packaging. For semiconductor substrate with copper interconnects architecture, Cu corrosion and surface residuals associated with post chemical-mechanical planarization cleaning are quite often the major reliability detractor to such an extent that its cleanness improvement becomes the most pivotal step in the successful qualification and implementation of the technology.
[0003] With the ever shrinking ground rule, new challenges emerge and new types of post-CMP cleaning related corrosion and residuals are observed in advanced technology nodes such as 22 nm and beyond. Ultra-low K dielectric with even higher porosity is adopted as interline dielectric materials. However, such type dielectrics become more affinitive to the post-CMP cleaning residue which leads to dielectric constant increase. Meanwhile, to meet demanding scale own feature size as well as electric performance, Cu barrier switches from traditional TaN/Ta to TiN, Ru, RuN, RuTa, RuTaN, W, WN, Co, TaRu, CuMn, CuAl, or CuFO, etc. Their electrochemistry associated potential corrosion needs to be taken care of along with Cu corrosion inhibition. Furthermore, in fine pitch Cu interconnects, the electric potential becomes greater while the diffusion path becomes shorter, creating an environment that will expedite the formation of corrosion-related defects such as hollow metal and dendrites. As a result, interline dielectric constant instability, Cu and Cu barrier corrosion becomes increasing critical in that such defects are generated during cleaning and the queue time which ultimately leads to reliability failure in the cause of time delayed dielectric breakdown (TDDB) and/or electric migration (EM) tests.
[0004] Since CMP is the final and enabling process before one level of Cu interconnect is fully defined, not only can it generate residuals during the process per se (e. g. polish residues), but it will also reveal defects generated from prior processing steps, such as post-RIE cleaning, Cu barrier deposition, and Cu plating. Therefore, not only must the post Cu CMP cleaning process clean up the residuals generated by CMP, but it must also render sufficient compatibility with prior processes to prevent exacerbating pre-existing defects incoming to CMP.
[0005] In general, CMP slurries frequently include one or more corrosion inhibitors which selectively form a temporary protective coating on the copper interconnect surface. However, if an organic coating should remain on the copper interconnect surface after the cleaning process, the presence of such a coating can interfere with subsequent steps, e.g., chemical vapor deposition (CVD), and with the ultimate performance of the copper interconnect. In post CMP cleaning processes, therefore, it is an imperative to minimize organic(s) remaining or no-detectable coating on the copper surfaces, but with sufficient protection to copper (including Cu barrier) interconnect.
[0006] Furthermore, corrosion inhibitors in post-CMP composition have the tendency of breakdown or oxidized while exposed to the air or oxygen saturated solution. Antioxidant or reduction agent often included in post-CMP solution to eliminate or reduce the level of oxidant. At the same time to minimize Cu oxidation introduced Cu loss and line surface roughness.
[0007] Accordingly, there remains a critical need for a unique post-CMP cleaning composition capable of providing synergistic functions as of residual removal, post-CMP temporary organic coating minimization, as well as Cu (including Cu barrier) corrosion inhibition without compromising performances of nano devices.
[0008] In the present disclosure, a cleaning composition, which is applied to the post chemical-mechanical planarization process of a semiconductor substrate containing a damascene metal structure, is provided. A cleaning composition may contain various chemicals that perform different functions during the cleaning process. A cleaning composition must contain a cleaning agent that removes polish residuals, such as CMP slurry particles, polish pad debris, polished metals and low-K dielectrics, from the surface of semiconductor substrate with damascene Cu interconnects. A cleaning composition may contain chelating agent, a combination of chelating agents, corrosion-inhibitor, and/or antioxidant. The cleaning agent of the current disclosure efficiently clean the surface of the planarized substrate by removing CMP slurry particles, cleaning residual metal and dielectrics, as well as minimizing temporary organic protective coating from surfaces of semiconductor substrate. A chelating agent or combined chelating agents form multi chemical bonds with transition metal ions to prevent re-deposition. Corrosion inhibitor together with antioxidant function by either deposit a few molecular thick layer of film on upmost metal surface or reduce oxygen to prevent oxidation or electrochemical reaction without adversely affecting the physical properties of contact interfaces of back-end-of-line buildups. To prevent foreign materials redeposit back onto low-k (or ultra low-k) dielectric surfaces, inhibitor and/or antioxidant also function as a wetting agent to lower the surface tension of dielectrics.
BRIEF DESCRIPTION OF DRAWINGS
[0009] FIG. 1 is a cross section representation illustrating a structure including an interconnect dielectric material having at least one opening present therein and located atop a semiconductor substrate that can be employed in one embodiment of the present disclosure.
[0010] FIG. 2 is a cross section representation illustrating the structure of FIG. 1 after forming a contiguous diffusion barrier liner material on exposed surfaces thereof.
[0011] FIG. 3 is a cross section representation illustrating the structure of FIG. 2 after depositing a conductive metal-containing material and performing chemical-mechanical planarization.
[0012] FIG. 4 is a cross section representation illustrating the structure of FIG. 3 after performing the post metal CMP cleaning process using present disclosure composition.
[0013] FIG. 5A shows results of breakdown accumulative vs. aging time with 3.63 volt bias at 125° C.
[0014] FIG. 5B shows results of time-to-breakdown at 63.2 percentile vs. voltage at 30° C.
DETAILED DESCRIPTION OF THE INVENTION
[0015] The present disclosure, which provides a post chemical-mechanical planarization cleaning composition for advanced interconnect technology, will now be described in detail with introduction of Cu interconnect containing wafer substrate formation by referring to the following discussion and drawings that render a background to the present disclosure. It is noted that the drawings of the present application are provided for illustrative purposes only and, as such, the drawings are not drawn to scale. In the following description, some specific details are set forth, such as particular structures, components, materials, dimensions, and processing steps, in order to provide a thorough understanding and application background of the present disclosure.
[0016] Reference is first made to FIGS. 1-4 which illustrates an embodiment in which a planarized interconnect structure is first formed, and then subjected to the post metal CMP cleaning process with present disclosure of cleaning composition. Although the description and drawings illustrate using the composition of the present disclosure on a planarized interconnect structure, the post-CMP cleaning composition can be used in other structures in which a metal interconnect embedded layer is subjected to chemical-mechanical planarization.
[0017] Referring first to FIG. 1 , there is an illustrated structure including an interconnect dielectric material 12 having at least one opening 14 present therein and located atop a semiconductor wafer, i.e., substrate, 8 that can be employed in cleaning process with cleaning composition of the present disclosure.
[0018] Examples of semiconductor materials that may be used as the semiconductor substrate 8 include, but are not limited to, Si, SiGe, SiGeC, SiC, Ge alloys GaAs, InAs, InP, SiO 2 , quartz, and alumina, zirconia, sapphire, magnesia, aluminum nitride, tungsten carbide, silicon nitride, and silicon carbide, and other II/V or II/VI compound substrates. In one embodiment, the semiconductor substrate 8 may comprise a bulk semiconductor substrate. In another embodiment, the semiconductor wafer 8 may comprise multilayers of semiconductor materials. In yet a further embodiment of the present disclosure, the semiconductor substrate 8 may comprise a semiconductor-on-insulator substrate such as, for example, a silicon-on-insulator semiconductor (SOI) substrate or a silicon germanium-on-insulator substrate.
[0019] A blanket layer of interconnect dielectric material is then formed atop the semiconductor substrate 8 . In some embodiments, an etch stop layer 10 can be formed between the semiconductor wafer 8 and the blanket layer of interconnect dielectric material. When present, the etch stop layer 10 may comprise a dielectric material such as, for example, SiC, Si 4 N 3 , SiO 2 , a carbon doped oxide, a nitrogen and hydrogen doped silicon carbide SiC(N,H), silicon nitride, silicon oxynitride and multilayers thereof. The etch stop layer 10 can be formed by a deposition process including, for example, chemical vapor deposition (CVD), plasma enhanced chemical deposition (PECVD), chemical deposition, evaporation and coating. When present, the thickness of the etch stop layer 10 is from 10 nm to 75 nm. Other thicknesses that are greater than or lesser than the thickness range mentioned above can also be used for the etch stop layer 10 .
[0020] The blanket layer of interconnect dielectric material may comprise any interlevel or intralevel dielectric including inorganic dielectrics or organic dielectrics. The blanket layer of interconnect dielectric material may be porous or non-porous. Some examples of suitable dielectrics that can be used as the blanket layer of interconnect dielectric material include, but are not limited to, SiO 2 , silsesquixoanes, C doped oxides (i.e., organosilicates) that include atoms of Si, C, O and H, thermosetting polyarylene ethers, or multilayers thereof. The term “polyarylene” is used in this application to denote aryl moieties or inertly substituted aryl moieties which are linked together by bonds.
[0021] The blanket layer of interconnect dielectric material typically has a dielectric constant that is about 4.0 or less, with a dielectric constant of about 2.8 or less being even more typical. These dielectrics generally have a lower parasitic crosstalk as compared with dielectric materials that have a higher dielectric constant than 4.0. The thickness of the blanket layer of interconnect dielectric material may vary depending upon the dielectric material used as well as the exact number of dielectrics within blanket layer of interconnect dielectric material. Typically, and for normal interconnect structures, the blanket layer of interconnect dielectric material has a thickness from about 200 to about 1000 nm. The blanket layer of interconnect dielectric material may be formed utilizing a deposition process including, for example, CVD, PECVD, chemical solution deposition, evaporation and spin-on coating.
[0022] The blanket layer of interconnect dielectric material is then subjected to a single or damascene process to form interconnect dielectric material 16 having at least one opening 14 therein. A single damascene process includes lithography and etching, while a dual damascene includes an iteration of lithography and etching. Lithographic includes forming a blanket layer of photoresist material (not shown) atop the blanket layer of interconnect dielectric material, exposing the photoresist material to a desired pattern of radiation, and then developing the exposed resist. Etching may include a dry etch such as, for example, reaction ion etching (RIE), ion beam etching, plasma etching and laser ablation. During one of the etch processes used to pattern the interconnect dielectric material, or in a separate etch there from, at least one portion of the etch stop layer 10 that is located at a lower segment of the at least one opening 14 and beneath the now patterned interconnect dielectric material 12 can be opened, as shown in FIG. 1 . The at least one opening 14 can be a via opening, a line (i.e., trench) opening, or a combined via (V) and line (L) opening as shown in FIG. 1 .
[0023] Referring now to FIG. 2 , there is illustrated the structure of FIG. 1 after forming a contiguous diffusion barrier liner material 16 on exposed surfaces of the structure including the uppermost surface of the interconnect dielectric material 12 and the sidewall surface of the interconnect dielectric material 12 within each opening 18 . The contiguous diffusion barrier liner material 16 may comprise Ta, TaN, Ti, TiN, Ru, RuN, RuTa, RuTaN, W, WN Co, TaRu, CuMn, CuAl, or CuFO, or any other material that can serve as a barrier to prevent conductive metal atoms from diffusing there through. Combinations of these materials can also be used forming a multilayered stacked diffusion barrier liner material. The contiguous diffusion barrier liner material 16 can be formed utilizing a deposition process such as, for example, atomic layer deposition (ALD), CVD, PECVD, physical vapor deposition (PVD), and sputtering. The thickness of the contiguous diffusion barrier liner material 16 may be from 5 nm to 50 nm. Other thicknesses that are greater than or lesser than the thickness range mentioned above can also be used for the contiguous diffusion barrier liner material 16 .
[0024] Referring to FIG. 3 , there is illustrated the structure of FIG. 2 after depositing a conductive metal-containing material and performing chemical-mechanical planarization. In the drawing, element 18 refers to a metal structure that comprises a remaining portion of the conductive metal-containing material after planarization, while element 16 ′ denotes a remaining portion of the contiguous diffusion barrier liner material 16 after planarization. The remaining portion of the contiguous diffusion barrier material 16 ′ is continuously present in the at least one opening 14 . Moreover and following planarization, the uppermost surfaces of the metal structure 18 and the remaining portion of the contiguous diffusion barrier material 16 ′ are coplanar with an uppermost surface of the interconnect dielectric material 12 .
[0025] The conductive metal-containing material used in forming the metal structure 18 includes a conductive metal, an alloy comprising at least two conductive metals, a conductive metal silicide or combinations thereof. In one embodiment of the present disclosure, the conductive metal-containing material used in forming the metal structure 18 comprises Cu, W and/or Al. In yet another embodiment of the present disclosure the conductive metal-containing material used in forming the metal structure 18 comprises Cu or a Cu alloy such as, for example, AlCu. The conductive metal-containing material is filled into the remaining portions of the at least one opening 18 in the interconnect dielectric material 16 utilizing a deposition process including, but not limited to, CVD, PECVD, sputtering, chemical solution deposition and plating. When plating is used, a plating seed layer can be formed prior to plating.
[0026] After deposition, a portion of the conductive metal-containing material extends outside of the at least one opening 14 onto portions of the contiguous diffusion barrier liner material 16 that are located on the uppermost surface of interconnect dielectric material 12 . This ‘excess’ portion of the conductive metal-containing material that extends outside of the at least one opening 14 and the portions of the contiguous diffusion barrier liner material 16 that are located on the uppermost surface of interconnect dielectric material 12 are then removed by chemical-mechanical planarization(CMP).
[0027] CMP is performed in any conventional polishing tool and a wide variety of conditions, i.e., polishing pressure, speeds, and polishing pads, as known to those skilled in the art can be employed. Also, various polishing slurries such as, for example, an alumina-based slurry and/or a silica-based slurry can be used. The CMP process can be conducted in two steps or three steps. In either embodiment, the final step of the CMP process removes at least the portions of the contiguous diffusion barrier liner material 16 that are located on uppermost surface of interconnect dielectric material 12 .
[0028] Referring now to FIG. 4 , there is illustrated the structure of FIG. 3 after performing the post metal CMP cleaning process with the composition of present disclosure. The post metal CMP cleaning process typically includes two steps of post CMP cleaning processes with the present disclosure composition. The first step may include two or more rounds of brush cleaning. During first around of clean cycle, a planarized semiconductor substrate containing at least one metal structure (one example being the structure shown in FIG. 3 ) is subjected to a brush clean with the present disclosure composition spraying towards the wafer surface through a nozzle. Approximately 2 liters of cleaning composition is consumed along with brushing to remove relative large particles and residuals from substrate surface. The second round of cleaning process basically repeats the same process as round one but more for fine particles and residuals removal. Both brush clean is performed in a roller brush station which includes at least one roller brush. The roller brush used in the brush clean step usually is comprised of a plastic. During the brush clean in the present disclosure composition, particles and residues are removed from the planarized surface of a semiconductor substrate containing at least one metal structure. The removal occurs by dissolving and brushing. However, cleaning process doesn't limited to brush cleaning. The second step is dipping cleaning. Post-CMP semiconductor substrate is immersed in a cleaning tank and exposed to present disclosure composition while continuously spinning. Dipping step is for finer residue and water mark removal from semiconductor substrate.
[0029] The term “post-CMP particles and residues” is used herein to mean and include all of the types of undesirable materials that are typically generated from polishing slurry, copper oxides, barrier metals, interline dielectrics, chemical reaction by-products from etching and ashing processes, and degraded foreign materials from brush, etc. They must be taken into account in designing the cleaning composition.
[0030] The present disclosure composition employed for the post CMP cleaning process provide efficacious cleaning to remove particles and residues from substrate surface consist of metal, dielectric and temporary no-detectable protective coating ( FIG. 4, 20 ) during the cleaning process. The term “No-detectable coating” used herein to mean that the protective coating is insignificant to the extent that it is no long capable of being detected by measurement as of electrochemical impedance spectroscopy. No-detectable coating may have similar chemical constituents as of corrosion inhibitors in CMP slurry and/or present disclosure composition.
[0031] The present disclosure composition is particularly useful for removing residues, e.g., post-CMP residues or residues from a microelectronic device structure formed post-etching or post-ashing without damaging the interconnect metals (e.g., copper), barrier layers(e.g., TaN, Co, RuTaN, etc.), and low-k dielectric materials.
[0032] The present disclosure composition is also particularly useful for removing residues, e.g., post-CMP, post-ashing or post etching particles and residues from Si interposer, quartz interposer, ceramic interposer, polymer interposer, as well as any dielectric buildup interposer on various substrates without damaging the interconnect metals (e.g., copper, aluminum, gold, etc.), barrier layers (e.g., passivated SiO 2 ), dielectric, and low-k dielectric materials.
[0033] A present disclosure composition used for post-CMP cleaning of a copper interconnect containing semiconductor substrate comprises at least:
[0034] (A) An alkaline aqueous solution in nature with a pH value in the range of 8.5-13.5. CMP slurry particles is stabilized in alkaline solution due to surface charge which results in repulsion from the water surface. An organic base and balance water are used for pH adjustment. The organic bases include, but not limited to, quaternary amine, including tetrahexylammonium hydroxide (THAH), tetramethylammonium hydroxide (TMAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), tetraethylammonium hydroxide (TEAH), trimethylphenylammonium hydroxide (TMPAH), tris(2-hydroxyethyl)methylammonium hydroxide (THEMAH), hexadecyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide (BTEAH), benzyltrimethylammonium hydroxide (BTMAH), benzylbis(2-hydroxyethyl)methylammonium hydroxide, tributylmethylammonium hydroxide (TBMAH), ammonium hydroxide, tetrabutylphosphonium hydroxide (TBPH), (2-hydroxyethyl) trimethylammonium hydroxide, (2-hydroxyethyl) triethylammonium hydroxide, (2-hydroxyethyl) tripropylammonium hydroxide, trimethyl-3-hydroxybutyl ammonium hydroxide, trimethyl-4-hydroxybutyl ammonium hydroxide, ethyltrimethylammonium hydroxide, diethyldimethylammonium hydroxide, 3-(trifluoromethyl) phenyltrimethylammonium hydroxide, and combinations thereof. The amount of organic base may be in a range from about 1.0 wt % to about 20 wt %, based on the total weight of the cleaning composition, but preferably from 1 wt % to about 10 wt %.
[0035] (B) A chelate agent, which helps prevent re-deposition of removed metal onto the wafer or interposer surface through metal complexation, includes, but not limited to, N,N,N′-trimethyl-N′-(2-hydroxyethyl) ethylenediamine, N,N-dimethylethylenediamine, N,N′-dimethylethanolamine, isobutanolamine, isopropanolamine, 2-(diethylamino) ethanol, aminoethylethanolamine, N-methylaminoethanol, aminoethoxyethanol, dimethylaminoethoxyethanol, diethanolamine, N-methyldiethanolamine, monoethanolamine, triethanolamine, 1-amino-2-propanol, 2-amino-1-butanol, isobutanolamine, triethylenediamine, EDTA, CDTA, HIDA, and N-AEP, 1-methoxy-2-aminoethane, tetraethylenepentamine (TEPA), gluconic acid, tartaric acid, dimethyl glyoxime, formic acid, fumaric acid, glutamic acid, glutamine, glutaric acid, glyceric acid, glycerol, glycolic acid, glyoxylic acid, histidine, iminodiacetic acid, isophthalic acid, itaconic acid, lactic acid, leucine, lysine, maleic acid, maleic anhydride, malic acid, malonic acid, mandelic acid, 2,4-pentanedione, phenylacetic acid, phenylalanine, phthalic acid, proline, propionic acid, pyrocatecol, pyromellitic acid, quinic acid, serine, sorbitol, succinic acid, terephthalic acid, trimellitic acid, trimesic acid, and combinations thereof. The amount of chelating agent(s) may be in a range of 1.0 wt % to 10 wt %, preferably 0.05 wt % to 5 wt % of total weight of disclosed cleaning composition.
[0036] (C) An corrosion inhibitor, which protects metal surface from attacking through oxidation and/or galvanic corrosion without compromising interference to atop dielectric deposition from CVD or PECVD, includes, but not limited to, purine compound, such as purine, guanine, hypoxanthine, xanthine, caffeine, uric acid, pyrimidine, aronixil, thonzylamine, buspirone, enazadrem, isoguanine, and methylated or deoxy derivatives thereof; ribosylpurine compound, such as N-ribosylpurine, adenosine, guanosine, 2-aminopurine riboside, 2-methoxyadenosine, and methylated or deoxy derivatives thereof, such as N-methyladenosine, N,N-dimethyladenosine, trimethylated adenosine. The corrosion inhibitors may comprise the combination of the aforementioned inhibitors, derivatives of aforementioned inhibitors, degraded products of aforementioned inhibitors, and oligomers of the aforementioned inhibitors. The inhibitors may be in a range of 0.0 wt % to 5.0 wt % of the total weight of post-CMP cleaning composition.
[0037] (D) An antioxidant, which reduces oxidant level in present disclosure composition, includes, but not limited to, gallate compound, such as ethyl gallate, propyl gallate, butyl gallate, octyl gallate, dodecyl gallate, catechin gallate, gallocatechin gallate; epicatechin, quercetin, resveratrol, menthol, hesperitin; and organic acid compounds, such as ascorbic acid, garlic acid. The antioxidants may comprise the combination of the aforementioned antioxidants, derivatives of aforementioned antioxidants, degraded products of aforementioned antioxidants, and oligomers of the aforementioned antioxidants. The antioxidants may be in a range of 0.0 wt % to 2.0 wt % of the total weight of post-CMP cleaning composition.
[0038] Preferred cleaning compositions comprise 1.0 wt % to 20 wt % of aqueous tris(2-hydroxyethyl) methylammonium hydroxide; 1.0 wt % to 10 wt % n,n-dimethylethylenediamine; 0.0 wt % to 2.0 wt % corrosion inhibitor from the group consisting guanosine, guanine, n-methyladenosine, xanthine and combinations thereof; 0.0 wt % to 1 wt % antioxidant from the group consisting ethyl gallate, quercetin, resveratrol and combinations thereof; and balance deionized water. Some preferred embodiments contain mixtures of more than one chelating agent and/or corrosion-inhibitor and/or antioxidant.
[0039] A present disclosure composition is easily formulated by simple addition of the respective ingredients and mixing to homogeneous condition. Furthermore, the compositions may be readily formulated as single-package formulations or multi-part formulations that are mixed at or before the point of use, e.g., the individual parts of the multi-part formulation may be mixed at the tool or in a storage tank upstream of the tool. The concentrations of the respective ingredients may be widely varied in specific multiples of the composition, i.e., more dilute or more concentrated, and it will be appreciated that the compositions described herein can variously and alternatively comprise, consist or consist essentially of any combination of ingredients consistent with the disclosure herein.
[0040] Present disclosure compositions described herein can be further diluted with, for example, deionized water, prior to the post-CMP cleaning process. The cleaning compositions are diluted before use or replenished during or after use wherein up to 500 parts water is added to the composition within about one day prior to the beginning of cleaning process with the resulting mixture. At other times the dilution water can be added to the composition within about one hour prior to the initiation of cleaning process with the resulting mixture. Satisfactory results have been observed with composition dilution factors of from about 1 to about 200.
[0041] As applied to semiconductor manufacturing operations, the cleaning compositions described herein are usefully employed to clean post-CMP, post-RIA and post-ashing residues from the surface of the microelectronic substrate containing metal interconnect structures. The cleaning compositions do not damage dielectric or low-k dielectric materials or corrode metal interconnects fabricated on substrates. Moreover, the cleaning compositions are compatible with the barrier liner material, wherein the barrier liners comprise at least one species selected from the group consisting of Ru, Co, W, Mo, Ta, Rh, Mn, TaN, SiO 2 , alloys thereof, and combinations thereof.
Example
[0042] The present disclosure is illustrated in more detail in the following example, which is for illustrative purposes and should not be construed as limiting the scope of the present disclosure.
[0043] A preferred cleaning composition comprising 8.0 wt % Tris(2-hydroxyethyl) methylammonium Hydroxide, 4.5 wt % N,N-dimethylethylenediamine, 0.2 wt % guanosine, 0.05 wt % ethyl gallate and balance deionized water was used for the post-CMP cleaning.
[0044] A Cu/ULK (SiOCH based ultra low-k film, k=2.4) patterned Si wafer substrate featured with 22 nm gate length and 40 nm line width were used for the post CMP cleaning test. Typically, ULK is a dielectric material of silsesquixoanes, C doped oxides (i.e., organosiliates) with high porosity which has a k-value less than 2.5. The wafers were polished using a CMP wafer polisher with a standard polishing recipe. After polishing, the wafers were cleaned with the present disclosure composition.
[0045] The post metal CMP cleaning process includes, as a first step, subjecting a planarized semiconductor wafer containing at least one metal structure (shown in FIG. 3 ) to a brush clean in present disclosed composition medium. This brush clean may be performed once or multiple times. The brush clean is performed in a roller brush station with mirror-like setting brushing both sides of a wafer. Within the roller brush station and during the brush clean process, the present disclosed composition medium can be continuously or intermediately introduced onto the planarized surface of the semiconductor wafer containing at least one metal structure by one or more spray nozzles. The brush clean can be performed at nominal room temperature from 15° C. to 40° C. Other temperatures can be employed as long as the temperature is not above the boiling point of the acidic medium. The brush clean step of the post metal CMP cleaning process of the present disclosure can be performed in an inert ambient such as, for example, N 2 , He and/or Ar.
[0046] The dipping, as a second step, of the post1 CMP cleaning process is performed in a tank that is capable of having one or more CMP processed semiconductor wafers immersed therein. The tank is equipped with a bleed line (for removing a quantity of present disclosure composition from the tank) and a feed line (for introducing a quantity of present disclosure composition into the tank). In some embodiments, the present disclosure composition is continuously being replenished by opening and closing the bleed/feed lines. During dipping process, the CMP processed semiconductor wafer is continuously spun during the dipping step.
[0047] Wafers with Cu metallization based on 22 nm design rules were utilized for the experiments. All wafers were polished with an alumina-based Cu slurry and then a silica-based barrier slurry. Two commercial available post-CMP cleaners (commercial cleaner I and commercial cleaner II) and the present invented post-CMP cleaning solution were processed on the polished wafers during first step and second step post-CMP cleanings. TDDB reliability tests are conducted on the cleaned wafers featured 22 nm node Cu interconnect. TDDB test results of breakdown cumulative vs. time with 3.63 volt at 125° C. and time-to-breakdown at 63.2 percentile vs. time at 30° C. are shown in FIG. 5A and FIG. 5B , respectively. Results indicate that TDDB reliabilities from present disclosure composition cleaned wafers outperform that from the commercial available cleaners I & II processed wafers while tested on the same Cu interconnect macro of large W1-chain. | This disclosure relates post chemical mechanical planarization cleaning composition of semiconductor substrate for advanced electronics fabrication and packaging. It provides novel corrosion inhibition and quality upmost Cu-low K surfaces to the demanding reliability of nano device and Cu interconnection. Its efficacious cleaning without changing of ultra-low K dielectric and interfering with ultimate electronics performance also offers a cleaning solution to the Cu-low K structure of post reactive ion etching as well as resist ashing in semiconductor fabrication process flow. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to an immunologic adjuvant and, more particularly to novel glycolipid immunologic adjuvant and to improved vaccine formulations containing a novel glycolipid immunologic adjuvant.
Broadly considered, the vaccines utilized at the present time are "fluid vaccines." The term "fluid vaccine" designates a suspension of an immunogenic or desensitizing agent in water or in a medium comprising a single, aqueous, liquid phase. The principal purpose for employment of an immunologic adjuvant is to achieve a more durable immunity of a higher level employing a smaller antigenic mass in a fewer number of doses than could be achieved by administration of the equivalent aqueous antigen. It may be noted that development of an immunologically satisfactory and pharmacologically acceptable adjuvant is a prime essential for the preparation of workable multivalent killed virus vaccines which are effective and practical in the prevention of viral, bacterial, mycoplasmal or rickettsial diseases.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide new glycolipid compounds. Another object is to provide methods for preparing these glycolipid compounds. A further object is to provide vaccine compositions containing these glycolipid compounds. These and other objects of the present invention will be apparent from the following description.
SUMMARY OF THE INVENTION
Glycolipid compounds of the formulae ##STR3## wherein R is ##STR4## are useful immunologic adjuvants in vaccines.
DETAILED DESCRIPTION
The glycolipid compounds of the present invention which are useful as immunologic adjuvants are prepared starting from per-O-acetyl-1-thioglycopyranose and 6-(5-cholesten-3β-yloxy)hexyl iodide. Equimolar amounts of the foregoing compounds may be condensed in an inert, non-polar solvent such as a halogenated solvent, e.g., dichloromethane or chloroform in the presence of a base such as, e.g., triethylamine, 1,5-diazabicyclo[5.4.0]-undec-5-ene, or 1,5-diazabicyclo[4.3.0]-non-5-ene. The reaction may be carried out at from about 10° to about 30° C. under an inert atmosphere. Depending upon the base employed the reaction may take from about half an hour to about a few days. Thus, when employing 1,5-diazabicyclo[5.4.0]-undec-5-ene, or 1,5-diazabicyclo[4.3.0]-non-5-ene the reaction is usually completed in from about 0.5 to about 3 hours, while when employing triethylamine the reaction is usually completed in from about 1 to about 3 days. Following the reaction the solution is washed with water and dried if the solvent was a halogenated solvent, or if the solvent was tetrahydrofuran, the solution is evaporated to dryness and the residue is partitioned between dichloromethane and water. The dried solution is concentrated to a syrup which is put on a silica gel column and eluted with chloroform followed by 1-2% ethanol in chloroform. The desired fractions are pooled and evaporated to give the blocked product 6-(5-cholesten-3β-yloxy)hexyl per-O-acetyl-1-thio-glycopyranoside which is deblocked by basic ion exchange treatment or sodium methoxide in methanol to give the desired final product.
The novel adjuvants of the invention may be employed to potentiate the antibody response of antigenic materials. The term "antigen" and "antigenic material" which are used interchangeably herein include one or more non-viable immunogenic or desensitizing (anti-allergic) agents of bacterial, viral or other origin. The antigen component of the products of the invention may consist of a dried powder, an aqueous solution, an aqueous suspension and the like, including mixtures of the same, containing a non-viable immunogenic or desensitizing agent or agents.
The aqueous phase may conveniently be comprised of the antigenic material in a parenterally acceptable liquid. For example, the aqueous phase may be in the form of a vaccine in which the antigen is dissolved in a balanced salt solution, physiological saline solution, phosphate buffered saline solution, tissue culture fluids or other media in which the organism may have been grown. The aqueous phase also may contain preservatives and/or substances conventionally incorporated in vaccine preparations. The adjuvant emulsions of the invention may be prepared employing techniques well known to the art.
The antigen may be in the form of purified or partially purified antigen derived from bacteria, viruses, rickettsia or their products, or extracts of bacteria, viruses, or rickettsia, or the antigen may be an allergen such as pollens, dusts, danders, or extracts of the same or the antigen may be in the form of a poison or a venom derived from poisonous insects or reptiles. In all cases the antigens will be in the form in which their toxic or virulent properties have been reduced or destroyed and which when introduced into a suitable host will either induce active immunity by the production therein of antibodies against the specific microorganisms, extract or products of microorganisms used in the preparation of the antigen, or, in the case of allergens, they will aid in alleviating the symptoms of the allergy due to the specific allergen. The antigens can be used either singly or in combination for example, multiple bacterial antigens, multiple viral antigens, multiple mycoplasmal antigens, multiple rickettsial antigens, multiple bacterial or viral toxoids, multiple allergens or combinations of any of the foregoing products can be combined in the aqueous phase of the adjuvant composition of this invention. Antigens of particular importance are derived from bacteria such as B. pertussis, Leptospira pomona and icterohaemorrhagiae, S. typhosa, S. paratyphi A and B, C. diphtheriae, C. tetani, C. botulinum, C. perfringens, C. feseri and other gas gangrene bacteria, B. anthracis, P, pestis, P. multocida, V. cholerae, Neisseria meningitidis, N, gonorrheae, Hemophilus influenzae, Treponema pollidum, and the like; from viruses as polio virus (multiple types), adeno virus (multiple types), parainfluenza virus (multiple types), measles, mumps, respiratory syncytial virus, influenza (various types), shipping fever virus (SF 4 ), Western and Eastern equine encephalomyelitis, Japanese B. encephalomyelitis, Russian Spring Summer encephalomyelitis, hog cholera virus, Newcastle disease virus, fowl pox, rabies, feline and canine distemper and the like viruses, from rickettsiae as epidemic and endemic typhus or other members of the spotted fever group, from various spider and snake venoms or any of the known allergens for example from ragweed, house dust, pollen extracts, grass pollens and the like.
The following examples illustrate the present invention without, however, limiting the same thereto. All temperatures are expressed in degrees celsius.
EXAMPLE 1
6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-L-fucopyranoside
A. 6-(5-Cholesten-3β-yloxy)hexyl 2,3,4-tri-O-acetyl 1-thio-β-L-fucopyranoside
2,3,4-Tri-O-acetyl-1-thio-β-L-fucopyranose (10 mmol) is treated with 6-(5-cholesten-3β-yloxy)hexyl iodide (10 mmol) in dichloromethane (30 ml) containing triethylamine (10 mmol). The reaction takes place in 1 day at room temperature under nitrogen. The resulting solution is washed with distilled water (20 ml) and dried with anhydrous sodium sulfate. The filtered solution is concentrated to form a syrup which is put on a silica gel column and eluted with chloroform followed by 1.0% ethanol in chloroform. The fractions containing the title compound, as determined by thin layer chromatography, are pooled and evaporated to give the title compound in 61% yield [α] D -4° (c 1.5, chloroform).
B. 6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-L-fucopyranoside
The blocked product from Step A is stirred with a basic ion exchange resin, Bio-Rad AG 1-X2 (OH), in ethanol-tetrahydrofuran or sodium methoxide in methanol to give the title compound as needles, yield 80%, m.p. 110°-112° (ethyl acetate), [α] D -11° (c 1.43, chloroform).
EXAMPLE 2
6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-D-glucopyranoside
A. 6-(5-Cholesten-3β-yloxy)hexyl 2,3,4,6-tetra-Oacetyl-1-thio-β-D-glucopyranoside
The product of Example 1A is repeated except using 2,3,4,6-tetra-O-acetyl-1-thio-β-D-glucopyranose (10 mmol) in lieu of 2,3,4-tri-O-acetyl-1-thio-β-L-fucopyranose and using 1,5-diazabicyclo[5.4.0]-undec-5-ene (10 mmol) in lieu of triethylamine. The reaction takes place in 2 hours at room temperature under nitrogen. The title compound is obtained in 86% yield, m.p. 101°-102.5° (methanol), [α] D -36° (c 1.59, chloroform).
B. 6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-D-glucopyranoside
The title compound is obtained following the procedure of Example 1B, yield 62%, m.p. 110° (aqueous isopropanol), [α] D -41° (c 1.07, chloroform), R f 0.27 (chloroform-methanol, 9:1).
EXAMPLE 3
6-(5-Cholesten-3β-yloxy)hexyl 2-acetamido-2-deoxy-1-thioβ-D-glucopyranoside
A. 6-(5-Cholesten-3β-yloxy)hexyl 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-1-thio-β-D-glucopyranoside
The procedure of Example 1 is repeated except using 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-1-thioβ-D-glucopyranose (10 mmol) in lieu of 2,3,4-tri-O-acetyl-1-thio-β-L-fucopyranose and using tetrahydrofuran (30 ml) in lieu of dichloromethane, and upon completion of the reaction, the mixture is evaporated to dryness and the residue partioned between dichloromethane (30 ml) and water (20 ml) and dried before forming the syrup which is put on the silica gel column. The title compound is obtained in 90% yield, m.p. 176°-179°, [α] D -43° (c 1.5, chloroform).
B. 6-(5-Cholesten-3β-yloxy)hexyl 2-acetamido-2-deoxy-1-thio-β-D-glucopyranoside
The title compound is obtained following the procedure of Example 1B, yield 77%, m.p. 183°-187° (dec) (methanol), [α] D -36° (c 1.5, dimethylsulfoxide), R f 0.48 (chloroform-methanol-water (80:20:2).
EXAMPLE 4
6-(5-Cholesten-3β-yloxy)hexyl 2-acetamido-2-deoxy-1-thio-β-D-galactopyranoside
A. 6-(5-Cholesten-3β-yloxy)hexyl 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-1-thio-β-D-galactopyranoside
The procedure of Example 2A is repeated except using 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-1-thio-β-D-galactopyranose (10 mmol) in lieu of 2,3,4,6-tetra-O-acetyl-1-thio-β-D-glucopyranose. The title compound is obtained as a crystalline material, yield 43%, m.p. 130°-133° (ethanol), [α] D -37° (c 1.5, chloroform).
B. 6-(5-Cholesten-3β-yloxy)hexyl 2-acetamido-2-deoxy1-thio-β-D-galactopyranoside
The title compound is obtained folllowing the procedure of Example 1B, yield 85%, m.p. 241°-243°, [α] D -35° (c 1.5, N,N-dimethylformamide).
EXAMPLE 5
6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-D-xylopyranoside
A. 6-(5-Cholesten-3β-yloxy)hexyl 2,3,4-tri-O-acetyl-1thio-β-D-xylopyranoside
The procedure of Example 2A is repeated except using 2,3,4-tri-O-acetyl-1-thio-β-xylopyranose in lieu of 2,3,4,6-tetra-O-acetyl-1-thio-β-D-glucopyranose. The title compound is obtained in 65% yield, m.p. 106°-108° (methanol), [α] D -56° (C 1.55, chloroform).
B. 6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-D-xylopyranoside
The title compound is obtained as a crystalline material following the procedure of Example 1B, m.p. 115° (methanol), [α] D -45° (c 1.47,
EXAMPLE 6
6-(5-Cholesten-3β-yloxy)hexyl 1-thio-α-L-arabinopyranoside
A. 6-(5-Cholesten-3β-yloxy)hexyl 2,3,4-tri-O-acetyl1-thio-α-L-arabinopyranoside
The procedure of Example 2A is repeated except using 2,3,4-tri-O-acetyl-1-thio-α-L-arabinopyranose (10 mmol) in lieu of 2,3,4,6-tetra-O-acetyl-1-thio-β-D-glucopyranose. The title compound is obtained in 64% yield, [α] D -22° (c 1.88, chloroform).
B. 6-(5-Cholesten-3β-yloxy)hexyl 1-thio-α-L-arabinopyranoside
The title compound is obtained following the procedure of Example 1B, yield 83%, [α] d -18° (c 2.0, chloroform).
EXAMPLE 7
6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-lactoside
A. 6-(5-Cholesten-3β-yloxy)hexyl hepta-O-acetyl-1-thio-β-lactoside
The procedure of Example 2A is repeated except using hepta-O-acetyl-1-thio-β-lactose (10 mmol) in lieu of 2,3,4,6-tetra-O-acetyl-1-thio-β-D-glucopyranose. The title compound is obtained in 46% yield, [α] D -22° (c 1.55 chloroform).
B. 6-(5-Cholesten-3β-yloxy)hexyl 1-thio-β-lactoside
The title compound is obtained as a crystalline material following the procedure of Example 1B, m.p. 189°-192° (aqueous isopropanol), [α] D -21° (c 1.63, dimethylsulfoxide), R f 0.26 (chloroform-methanol-water, 80:20:2).
EXAMPLE 8
2-S-[6-(5-Cholesten-3β-yloxy)hexyl]-2-thio-β-D-N-acetylneuraminic acid
A. 6-(5-Cholesten-3β-yloxy)-hexane-1-thiol
Thiourea (7.5 g) is added to a solution of 6-(5-cholesten-3β-yloxy)hexyl iodide (15 g, 25.3 mmol) in tetrahydrofuran (200 ml) and the mixture is heated with stirring under reflux for 6 hours. The solution is concentrated to a residue which is triturated with anhydrous ether. The solid is filtered and dissolved in chloroform (100 ml). This solution is added to a solution of potassium metabisulfite (15 g) in water (100 ml). The mixture is heated under reflux in a nitrogen atmosphere for 20 minutes. The organic layer is washed with water, dried, and concentrated to dryness. The crude material is put on a silica gel column and eluted with 5% ethyl ether in peteroleum ether. The dried fractions are pooled and concentrated to give the title compound (11 g, 86% yield), m.p. 89°-90°.
B. Methyl 4,7,8,9-tetra-O-acetyl-N-acetyl-2-S-[6-(5-cholesten-3β-yloxy)hexyl]-2-thio-D-neuraminate
Boron trifluoride etherate (700 μl, 5.5 mmol) is added to a solution of methyl 2,4,7,8,9-penta-O-acetyl-N-acetyl-D-neuraminate (1.01 g, 1.96 mmol) and 6-(5-cholesten-3β-yloxy)-hexane-1-thiol (0.98 g, 1.96 mmol) in dry chloroform (5 ml). The mixture is stirred under nitrogen for 5 hours at room temperature, and washed with aqueous sodium bicarbonate and water. The dried solution is concentrated to a residue which is put on a silica gel column and eluted with chloroform-ethyl ether-methanol (31:10:1). The β-anomer is isolated as a glass (400 mg), [α] D -38.5° (c 1.5, chloroform).
C. 2-S-[6-(5-Cholesten-3β-yloxy)hexyl]-2-thio-β-D-N-acetylneuraminic acid
A solution of the blocked glycolipid (46 mg) in dry methanol (8 ml) containing sodium methoxide (3 mg) is kept for 3 hours at room temperature. The medium is adjusted to pH 9 by gradual addtion of 2.5 N sodium hydroxide (10 drops). The suspension is stirred for 16 hours and tetrahydrofuran (20 ml) is added to dissolve the precipitates. The solution is de-ionized with acidic resin, filtered, and concentrated to dryness. The residue is triturated with ethyl ether-petroleum ether to give the title compound (30 mg, 80% yield).
EXAMPLE 9
An aqueous suspension of the final product of Example 1 in phosphate buffered saline (PBS) is sterile filtered and added in levels of 0.005 mg and 0.05 mg to 2 samples of bivalent whole influenza vaccine (A Victoria and B Hong Kong strains). Similar adjuvant vaccine preparations are prepared using the final products of examples 2-8. | Glycolipid compounds of the formulae ##STR1## wherein R is ##STR2## are useful immunologic adjuvants in vaccines. | 0 |
TECHNICAL FIELD
[0001] The present invention relates to a drive device for use on a vehicle with an electric motor, which includes at least a drive motor as a drive source that is coupled to a drive wheel by constant velocity universal joints.
BACKGROUND ART
[0002] Some vehicles such as automobiles or the like include a drive motor as a drive source. Actually, there are known in the art hybrid automobiles having an engine and a drive motor and vehicles with an electric motor, such as electric automobiles (or fuel-cell electric automobiles) having only a drive motor as a drive source.
[0003] Such vehicles with an electric motor are generally propelled when their drive wheels (tires) are rotated under rotational forces that are transmitted from the drive motor through constant velocity universal joints to the drive wheels.
[0004] One known technology of the kind described above is a drive mechanism for electric automobiles as disclosed in Japanese Laid-Open Patent Publication No. 04-325803, for example. As shown in FIG. 11 , the drive mechanism includes a motor case 1 and a stator 3 with coils 2 wound thereon, the stator 3 being pressure-fitted in the motor case 1 . The motor case 1 houses therein a cup-shaped rotor 4 of an air-core motor which rotates under magnetic forces from permanent magnets 5 . A motor-side constant velocity universal joint 6 is fixed to an inner surface of the bottom of the cup-shaped rotor 4 and coupled to an end of a drive shaft 7 whose other end is connected to a tire 9 through a tire-side constant velocity universal joint 8 .
[0005] The drive shaft 7 has a portion extending into the air core of the cup-shaped rotor 4 . The length of the drive shaft 7 can be made more than twice the length of the drive shaft in conventional drive mechanisms.
SUMMARY OF INVENTION
[0006] According to the above drive mechanism, the cup-shaped rotor 4 that is disposed in the motor case 1 makes it possible to provide an air-core motor. However, since the air core is included in the motor, the motor in its entity is considerably large in radial directions.
[0007] It is a general object of the present invention to provide a drive device for a vehicle with an electric motor, which does not need an air core therein.
[0008] A major object of the present invention is to provide a drive device for a vehicle with an electric motor, which is reduced in size and weight.
[0009] Another object of the present invention is to provide a drive device for a vehicle with an electric motor, which can maintain the stroke of a drive shaft.
[0010] Still another object of the present invention is to provide a drive device for a vehicle with an electric motor, which is capable of well increasing an output torque.
[0011] The present invention is concerned with a drive device for use on a vehicle with an electric motor, which includes at least a drive motor as a drive source that is coupled to a drive wheel by an inboard constant velocity universal joint, a drive shaft, and an outboard constant velocity universal joint.
[0012] According to an embodiment of the present invention, the inboard constant velocity universal joint is housed in an inner circumferential region of the drive motor, and includes an outer cup having, on an inner circumferential surface thereof, a sliding surface held in sliding contact with a joint member and having an outer circumferential surface rotatably supported on an inner circumferential surface of the drive motor.
[0013] The outer cup of the inboard constant velocity universal joint is rotatably supported on the inner circumferential surface of the drive motor. Therefore, the rotational force of the drive motor is directly transmitted to the outer cup. Therefore, the drive force is reliably and easily transmitted to the inboard constant velocity universal joint, and the drive device does not need the conventional air core and hence is reduced in size and weight.
[0014] Furthermore, the joint member of the inboard constant velocity universal joint is housed within the inner circumferential region of the drive motor, thus allowing the drive shaft to well maintain a stroke.
[0015] In the drive device, preferably, a speed reducer mechanism is housed in the inner circumferential region of the drive motor, the speed reducer mechanism reducing speed of rotation of the drive motor and transmitting the rotation to the inboard constant velocity universal joint.
[0016] According to another embodiment of the present invention, the inboard constant velocity universal joint includes an outer cup housing a joint member therein, and a shaft projecting axially outwardly from a bottom of the outer cup. The drive device further comprises a speed reducer mechanism coupled to the shaft and housed in an inner circumferential region of the drive motor.
[0017] With the above arrangement, the rotational force of the drive motor is directly transmitted to the outer cup by the speed reducer mechanism. Therefore, the drive force is reliably and easily transmitted to the inboard constant velocity universal joint.
[0018] Therefore, the drive device does not need the conventional air core and hence is reduced in size and weight. It is possible for the drive device to well increase the output torque with a speed reduction ratio set by the speed reducer mechanism.
[0019] In the drive device, the speed reducer mechanism should preferably comprise a sun gear mounted on a rotor of the drive motor, a planet gear supported on a carrier which is fixed to the shaft, an internal gear fixed to a stator of the drive motor. Preferably, the sun gear, the planet gear, and the internal gear are housed in an inner circumferential region of the rotor.
BRIEF DESCRIPTION OF DRAWINGS
[0020] FIG. 1 is a view of a vehicle incorporating a drive device for a vehicle with an electric motor according to a first embodiment of the present invention;
[0021] FIG. 2 is a schematic cross-sectional view of the drive device;
[0022] FIG. 3 is a schematic cross-sectional view of a drive device for a vehicle with an electric motor according to a first modification of the first embodiment;
[0023] FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3 , showing a speed reducer mechanism of the drive device;
[0024] FIG. 5 is a schematic cross-sectional view of a drive device for a vehicle with an electric motor according to a second modification of the first embodiment;
[0025] FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 5 , showing a speed reducer mechanism of the drive device;
[0026] FIG. 7 is a view of a vehicle incorporating a drive device for a vehicle with an electric motor according to a second embodiment of the present invention;
[0027] FIG. 8 is a schematic cross-sectional view of the drive device;
[0028] FIG. 9 is a cross-sectional view taken along line IX-IX of FIG. 8 , showing a speed reducer mechanism of the drive device;
[0029] FIG. 10 is a view showing the manner in which the speed reducer mechanism operates; and
[0030] FIG. 11 is a view of a drive mechanism disclosed in Japanese Laid-Open Patent Publication No. 04-325803.
DESCRIPTION OF EMBODIMENTS
[0031] Drive devices for a vehicle with an electric motor according to preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
[0032] As shown in FIG. 1 , a drive device 10 for a vehicle with an electric motor according to a first embodiment of the present invention is mounted on a vehicle 11 having a drive wheel DW that is coupled to the drive device 10 through a drive shaft 12 .
[0033] The drive wheel DW is resiliently supported on a vehicle body by a suspension SP. The suspension SP includes a link mechanism L coupling the drive wheel DW to the vehicle body and a shock absorber SA that absorbs vibrations applied to the drive wheel DW.
[0034] An inboard joint (inboard constant velocity universal joint) 16 that is coupled to a drive motor 14 is connected to one end of the drive shaft 12 . The inboard joint 16 comprises a tripod constant velocity universal joint, for example. The other end of the drive shaft 12 is connected to an outboard joint (outboard constant velocity universal joint) 17 that is coupled to the drive wheel DW.
[0035] As shown in FIG. 2 , the one end of the drive shaft 12 has a splined shaft 18 , and the inboard joint 16 has a joint member, e.g., a spider 20 , fitted over the splined shaft 18 . The spider 20 has a plurality of, e.g., three, trunnions 22 integral with the outer circumferential surface thereof, the trunnions 22 being angularly spaced at predetermined angular intervals (equal angular intervals).
[0036] Ring-shaped rollers 26 are rotatably supported on the outer circumferential surfaces of the respective trunnions 22 by respective rolling members (needles, rollers, or the like) 24 .
[0037] The inboard joint 16 has a bottomed hollow cylindrical outer cup 28 having a shaft 30 integral with one end (bottom end) thereof and an open opposite end.
[0038] The outer cup 28 has an inner circumferential region 32 with a plurality of, e.g., three, guide grooves 34 defined therein in which the rollers 26 are rollingly movable. The guide grooves 34 are angularly spaced at equal angular intervals and extend axially of the outer cup 28 .
[0039] A boot 36 has opposite ends fastened respectively to the tip of the open end of the outer cup 28 and the drive shaft 12 by respective bands 38 .
[0040] The drive motor 14 includes a motor case 40 made up of a first case member 40 a and a second case member 40 b . The second case member 40 b houses therein a plurality of coils 44 disposed in an annular pattern, making up a stator 42 . The coils 44 are connected to a drive circuit 46 , and the stator 42 includes a Hall device 48 for detecting a magnetic field.
[0041] The drive motor 14 comprises a brushless motor. The Hall device 48 detects a magnetic field for the drive circuit 46 to determine timings to control and switch between S and N poles.
[0042] A rotor 50 is disposed in the stator 42 . The rotor 50 includes the outer cup 28 and a plurality of permanent magnets 52 directly fixed to the outer circumferential surface of the outer cup 28 . The outer cup 28 is rotatably supported in the first case member 40 a and the second case member 40 b by a plurality of angular bearings 54 . The permanent magnets 52 are disposed in an annular pattern on the outer circumferential surface of the outer cup 28 , with their S and N poles alternating with each other.
[0043] Operation of the drive device 10 thus constructed will be described below.
[0044] The drive motor 14 , which comprises a brushless DC motor, has its S and N poles controlled and switched over by the drive circuit 46 . The outer cup 28 is rotated under repulsive and attractive forces generated between the coils 44 and the permanent magnets 52 with the S and N poles alternating with each other on the outer circumferential surface of the outer cup 28 .
[0045] The rotational force is transmitted from the outer cup 28 to the drive shaft 12 through the spider 20 with the rollers 26 held in sliding contact with the inner circumferential region 32 of the outer cup 28 . The rotational force is then transmitted to the drive wheel DW that is coupled to the outboard joint 17 connected to the drive shaft 12 (see FIG. 1 ), thereby propelling the vehicle.
[0046] According to the first embodiment, the outer cup 28 of the inboard joint 16 is rotatably supported in an inner circumferential region of the motor case 40 of the drive motor 14 by the angular bearings 54 .
[0047] The outer cup 28 with the permanent magnets 52 disposed on the outer circumferential surface thereof serves as the rotor 50 . The rotational force of the drive motor 14 is directly transmitted to the outer cup 28 . Therefore, the drive force (rotational force) is reliably and easily transmitted to the inboard joint 16 , and the drive device 10 does not need the conventional air core and hence is reduced in size and weight.
[0048] The spider 20 as the joint member of the inboard joint 16 is housed within an inner circumferential region of the drive motor 14 , thus allowing the drive shaft 12 to well maintain a stroke.
[0049] FIG. 3 is a schematic cross-sectional view of a drive device 60 for a vehicle with an electric motor according to a first modification of the first embodiment.
[0050] Those parts of the drive device 60 which are identical to those of the drive device 10 according to the first embodiment are denoted by identical reference characters, and will not be described in detail below. Similarly, those parts of a second modification of the first embodiment, to be described later, which are identical to those of the drive device 10 according to the first embodiment, will not be described in detail below.
[0051] The drive device 60 includes a drive motor 62 having a stator 42 and a rotor 64 . The rotor 64 has a shaft 66 rotatably supported centrally in a motor case 40 by angular bearings 54 , and a ring 68 of a relatively large diameter is integrally joined to an inner end of the shaft 66 . A plurality of permanent magnets 52 are disposed in an annular pattern on the outer circumferential surface of the ring 68 , with their S and N poles alternating with each other.
[0052] A speed reducer mechanism 72 is disposed between an outer cup 70 of an inboard joint 16 and the rotor 64 . As shown in FIGS. 3 and 4 , the speed reducer mechanism 72 has a sun gear 74 fixed to the rotational central axis of the rotor 64 , a plurality of, e.g., three, planet gears 76 rotatably supported on an end face 70 a of the outer cup 70 , and an internal gear 78 having teeth on its inner circumferential region and extending in a direction perpendicular to the end face 70 a of the outer cup 70 . The planet gears 76 are held in mesh with the sun gear 74 and the internal gear 78 .
[0053] According to the first modification, the rotor 64 rotates under a switching action of the drive circuit 46 . The sun gear 74 fixed coaxially to the rotor 64 rotates in the direction indicated by the arrow a 1 in FIG. 4 , for example.
[0054] The planet gears 76 are held in mesh with the sun gear 74 . When the sun gear 74 rotates in the direction indicated by the arrow a 1 , a rotational force in the direction indicated by the arrow b 1 is applied to each of the planet gears 76 . The planet gears 76 are also held in mesh with the internal gear 78 .
[0055] The planet gears 76 are rotatably supported on the end face 70 a of the outer cup 70 , and the internal gear 78 is directly disposed in the outer cup 70 . Therefore, the outer cup 70 rotates in the direction indicated by the arrow c in FIG. 4 . The speed reducer mechanism 72 reduces the speed based on the gear ratios between the sun gear 74 , the planet gears 76 , and the internal gear 78 .
[0056] According to the first modification, as described above, the speed reducer mechanism 72 is effectively to increase the ability to transmit the rotational force from the drive motor 62 to the inboard joint 16 and also to be able to set a torque and a rotational speed to desired levels.
[0057] FIG. 5 is a cross-sectional view of a drive device 90 for a vehicle with an electric motor according to a second modification of the first embodiment.
[0058] The drive device 90 includes a drive motor 92 having a stator 42 and a rotor 94 . The rotor 94 has a shaft 96 rotatably supported axially centrally in a motor case 40 . A ring 68 and an enlarged boss 98 are integrally joined to an inner end of the shaft 96 .
[0059] The drive device 90 includes a speed reducer mechanism 100 . As shown in FIGS. 5 and 6 , the speed reducer mechanism 100 has a sun gear 102 on an outer circumferential surface of the enlarged boss 98 of the rotor 94 , a plurality of, e.g., three, planet gears 106 supported on an outer cup 104 of the inboard joint 16 , and an internal gear 108 disposed on the motor case 40 .
[0060] The planet gears 106 are rotatably mounted on a carrier 110 fixed to the tip end of the outer cup 104 , and are angularly spaced at equal angular intervals. The internal gear 108 is disposed on the tip end of an inner circumferential of a hollow cylindrical member 112 that extends from an inner circumferential end of a second case member 40 b into a first case member 40 a.
[0061] According to the second modification, for example, the rotor 94 rotates in the direction indicated by the arrow a 2 in FIG. 6 under a switching action of the drive circuit 46 . The sun gear 102 on the enlarged boss 98 of the rotor 94 now rotates in the direction indicated by the arrow a 2 , and the planet gears 106 that are held in mesh with the sun gear 102 rotate in the direction indicated by the arrow b 2 .
[0062] The planet gears 106 are held in mesh with the internal gear 108 on the hollow cylindrical member 112 of the motor case 40 . Therefore, when the planet gears 106 rotate in the direction indicated by the arrow b 2 , the outer cup 104 is caused by the carrier 110 to rotate in the direction indicated by the arrow d, which is opposite to the direction indicated by the arrow c.
[0063] According to the second embodiment, therefore, the rotation of the drive motor 92 is reduced in speed and reliably transmitted to the inboard joint 16 , thereby offering the same advantages as those of the first embodiment
[0064] A second embodiment of the present invention will be described below. Those parts of the second embodiment which are identical to those of the drive device shown in FIGS. 1 through 6 are denoted by identical reference characters, and will not be described in detail below.
[0065] As shown in FIG. 7 , a drive device 210 for a vehicle with an electric motor according to the second embodiment is mounted on a vehicle 11 having a drive wheel DW that is coupled to the drive device 210 through a drive shaft 12 .
[0066] The drive wheel DW is resiliently supported on a vehicle body by a suspension SP. The suspension SP includes a link mechanism L coupling the drive wheel DW to the vehicle body and a shock absorber SA that absorbs vibrations applied to the drive wheel DW.
[0067] An inboard joint (inboard constant velocity universal joint) 216 that is coupled to a drive motor 214 is connected to one end of the drive shaft 12 . The inboard joint 216 comprises a tripod constant velocity universal joint, for example. The other end of the drive shaft 12 is connected to an outboard joint (outboard constant velocity universal joint) 17 that is coupled to the drive wheel DW.
[0068] As shown in FIG. 8 , the one end of the drive shaft 12 has a splined shaft 18 , and the inboard joint 216 has a joint member, e.g., a spider 20 , fitted over the splined shaft 18 . The spider 20 has a plurality of, e.g., three, trunnions 22 integral with the outer circumferential surface thereof, the trunnions 22 being angularly spaced at predetermined angular intervals (equal angular intervals). The inboard joint 216 may comprise any of various conventional constant velocity universal joints.
[0069] Ring-shaped rollers 26 are rotatably supported on the outer circumferential surfaces of the respective trunnions 22 by respective rolling members (needles, rollers, or the like) 24 .
[0070] The inboard joint 216 has a bottomed hollow cylindrical outer cup 228 having a shaft 230 integrally projecting axially outwardly from a bottom (one end) thereof and an open opposite end.
[0071] The outer cup 228 has an inner circumferential region 232 with a plurality of, e.g., three, guide grooves 34 defined therein in which the rollers 26 are rollingly movable. The guide grooves 34 are angularly spaced at equal angular intervals and extend axially of the outer cup 228 .
[0072] A boot 36 has opposite ends fastened respectively to the tip of the open end of the outer cup 228 and the drive shaft 12 by respective bands 38 .
[0073] The drive device 210 includes a speed reducer mechanism 240 coupled to the shaft 230 of the outer cup 228 and housed in an inner circumferential region of the drive motor 214 . The drive motor 214 has a motor case 242 having a bottomed hollow cylindrical shape. The motor case 242 includes a disk-shaped bottom 242 a on one end thereof.
[0074] As shown in FIGS. 8 and 9 , the motor case 242 houses therein a plurality of coils 246 disposed in an annular pattern, making up a stator 244 . The coils 246 are connected to a drive circuit, not shown. The drive motor 214 comprises a brushless DC motor, for example.
[0075] A rotor 248 is disposed in an inner circumferential region of the stator 244 . As shown in FIG. 8 , the rotor 248 has a shaft 252 rotatably supported centrally in the bottom 242 a of the motor case 242 by a bearing 250 . The shaft 252 has an integral ring 256 of a relatively large diameter joined thereto through a disk 254 . An enlarged boss 258 is disposed inwardly of the shaft 252 and integrally coupled coaxially therewith.
[0076] The ring 256 accommodates therein a plurality of permanent magnets 260 disposed in an annular pattern with their S and N poles alternating with each other. The rotor 248 may comprise a laminated assembly of magnetic steel sheets, rather than the permanent magnets 260 .
[0077] The speed reducer mechanism 240 has a sun gear 262 on an outer circumferential surface of the enlarged boss 258 of the rotor 248 , a plurality of, e.g., three, planet gears 264 supported on the outer cup 228 of the inboard joint 216 , and an internal gear 266 disposed on the motor case 242 . In the speed reducer mechanism 240 , the sun gear 262 , the planet gears 264 , and the internal gear 266 are housed in an inner circumferential region of the rotor 248 .
[0078] The planet gears 264 are rotatably mounted on a carrier 268 fixed to the tip end of the shaft 230 of the outer cup 228 , and are angularly spaced at equal angular intervals (see FIGS. 8 and 9 ). As shown in FIG. 8 , a disk 270 has a radially outer end integrally or separately joined to an open end of the motor case 242 and a radially inner end that is integrally joined to a tubular member 272 . The internal gear 266 is disposed on an inner circumferential surface of the tubular member 272 .
[0079] The shaft 230 of the outer cup 228 is rotatably supported in the motor case 242 by bearings 274 disposed between the shaft 230 and the tubular member 272 . The enlarged boss 258 of the rotor 248 is relatively rotatably held in engagement with the tip end of the shaft 230 .
[0080] Operation of the drive device 210 thus constructed will be described below.
[0081] When an electric current flows through the coils 246 of the stator 244 , they generate electromagnetic forces in the drive motor 214 . The rotor 248 including the ring 256 is rotated under repulsive and attractive forces generated between the coils 246 and the permanent magnets 260 with the S and N poles alternating with each other on the ring 256 .
[0082] As shown in FIG. 10 , when the rotor 248 rotates in the direction indicated by the arrow a 3 , for example, the sun gear 262 on the enlarged boss 258 of the rotor 248 rotates in unison with the rotor 248 in the direction indicated by the arrow a 3 .
[0083] The planet gears 264 are held in mesh with the sun gear 262 . When the sun gear 262 rotates in the direction indicated by the arrow a 3 , a rotational force in the direction indicated by the arrow b 3 is applied to each of the planet gears 264 . The planet gears 264 are also held in mesh with the internal gear 266 . The internal gear 266 is disposed on the inner circumferential surface of the tubular member 272 fixed to or integral with the motor case 242 .
[0084] When the planet gears 264 rotate in the direction indicated by the arrow b 3 , therefore, the outer cup 228 is caused by the carrier 268 to rotate in the direction indicated by the arrow a 3 . The speed reducer mechanism 240 reduces the speed based on the gear ratios between the sun gear 262 , the planet gears 264 , and the internal gear 266 .
[0085] The rotational force is transmitted from the outer cup 228 to the drive shaft 12 through the spider 20 with the rollers 26 held in sliding contact with the inner circumferential region 232 of the outer cup 228 . The rotational force is then transmitted to the drive wheel DW that is coupled to the outboard joint 17 connected to the drive shaft 12 (see FIG. 7 ), thereby propelling the vehicle.
[0086] According to the second embodiment, as shown in FIG. 8 , the speed reducer mechanism 240 is coupled to the shaft 230 that projects axially outwardly from the bottom of the outer cup 228 of the inboard joint 216 , and housed in an inner circumferential region of the drive motor 214 . Consequently, the rotational force from the drive motor 214 is directly transmitted through the speed reducer mechanism 240 to the outer cup 228 , so that the drive force can reliably and easily be transmitted to the inboard joint 216 .
[0087] Therefore, the drive device 210 does not need the conventional air core and hence is reduced in size and weight. It is possible for the drive device 210 to well increase the output torque with a speed reduction ratio set by the speed reducer mechanism 240 . | The present invention relates to a drive device for a vehicle with an electric motor, for which at least a drive motor is utilized as a drive source, and the drive motor and a drive wheel are connected by means of a constant velocity universal joint. The drive device is provided with a drive motor. A drive shaft is connected to the drive motor via an inboard joint. The inboard joint is housed at the inner periphery section of the drive motor. An outer cup, a constituent of the inboard joint, is provided with a guide race on the inner periphery section in order for a roller member to slide. The outer periphery section of the outer cup is rotatably supported by the inner periphery section of the drive motor. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of German Patent Application No. DE 10 2007 014 835.8-16 filed on Mar. 19, 2007, hereby incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates to an air conditioning unit for the conditioning of vehicles. Such air conditioning units are used in vehicles for conditioning the air in the passenger compartment, providing the passengers with a comfortable atmosphere while through conditioning the air at defined places preventing the window glasses from becoming fogged and, if necessary, enabling that the window glasses can be efficiently made free from ice. De-icing also helps enhance the safety of the vehicle passengers in bad weather conditions.
BACKGROUND OF THE INVENTION
[0003] Generally, in vehicles there is a demand that because of the great number of technical components used in modern vehicles optimization is performed with regard of the space requirements of the individual components in order to be able to realize the desired functional variety by installing the appropriate components. Therefore, large-volume components for conditioning the air such as mixing chambers, flow guiding and vortexing devices, as they are known from stationary air conditioning units, cannot be used because of the space conditions.
[0004] Another important demand of vehicle air conditioning units is, among others, that the different air outlets of the air conditioning unit should be provided with air tempered differently depending on the position and function of the respective outlet. There is no question that the individual temperatures can be controlled within certain limits by means of damper doors and various control mechanisms but in general, there is a demand of providing the air flows to the respective outlets with preset temperature according to the respective requirement profile. Layering the air flows allows reducing the space requirements, making the saved volume available for other components in the vehicle.
[0005] Prior art knows various approaches to establish air flow layering.
[0006] One known basic principle is tapping hot air in a zone above a heat exchanger and direct said hot air through a hot air channel toward the defroster air outlets, which are situated in the upper part of the air conditioning device. Typically, the inlet of the hot air channel is below one of the air outlets into the footwell of the passenger compartment. Therefore, the temperature of the respective outlet leading into the footwell is reduced whereas the temperature of the defroster air outlet below that the hot air channel ends is increased. Temperature layering between footwell and defroster air outlets is improved by installing this type of hot air channel.
[0007] As the hot air flowing within the hot air channel is not influenced by the cold air outside the channel, a hot air channel is an efficient method of improving temperature layering. Provided that the hot air channel is given the adequate shape, pressure loss and noise level of the air conditioning device are only marginally increased, or even reduced.
[0008] If, however, the automobile manufacturer demands less temperature layering over the whole control region of the mixing door for the air conditioning device, no satisfying result can be reached with a hot air channel tapping hot air below the footwell air outlet, only directing this air toward the defroster channel. Neither the amount of hot air that reaches the defroster air outlet, nor the direction in that the air is distributed after having left the hot air channel can be controlled. The temperature of the air flowing toward the dashboard and the outlets for the driver and the passenger cannot be influenced using this type of hot air channel.
[0009] Frequently it is necessary to insert air baffles in order to further enhance temperature layering, especially for controlling the temperature of the air flowing toward the dashboard and the footwell. Depending on dimensions and arrangement of said baffles, pressure losses and noise level of the air conditioning device will be noticeably raised and in addition, space requirements of the devices are increased.
[0010] EP 1 405 743 B1 discloses a device for heating and/or air conditioning a vehicle interior with reduced pressure losses. It is proposed to connect a cold air chamber and a hot air chamber with two additional mixing chambers that feed the accompanying air outlets. Additional providing mixing chambers does have the desired result of ensuring a defined homogeneous temperature at the respective air outlets but this solution is inevitably coupled with increased installation space or additional inserts, leading to increased noise when operated.
[0011] From DE 10 337 196 A1 an air conditioning device, especially a heating or air conditioning system for vehicles is known, which has a casing provided with heat exchangers and means for dividing an air flow into two hot air partial flows heatable in the heat exchanger and into two cold air partial flows bypassing the heat exchanger. For that to be achieved two air mixing chambers are provided with a hot air partial flow and a cold air partial flow being combined in each chamber. The air mixing chambers are equipped with air inlets for the partial air flows and air outlets for mixed air to be fed to the seat areas. In order to be capable to control the temperature of the air in the footwell of the passenger cell independent of the temperature on the central level as well as in the head area, the mixed air flows exiting separately through the outlets of the two air mixing chambers are fed to the seat area in such a manner that the air flow exiting from one air mixing chamber flows into the bottom region of the seat area and the air flow exiting from the other air mixing chamber flows into the top region of the seat area.
[0012] This proposed solution has the particular disadvantage that room is needed for the split off, separately led cold air flows, which results in additional channels, hence additional installation space.
[0013] Further, DE 10 161 753 A1 discloses a heating or air conditioning system for vehicles that is provided downstream of a heater with an upper mixing chamber and a lower mixing chamber, each feedable through an upper cold air channel and a lower cold air channel, said channels situated above or below, respectively, the heater. From the lower mixing chamber, air can be directed through flow chambers positioned to the side of the heater to both the footwell of the passenger compartment and the connections of the defroster nozzles positioned on top. This heating or air conditioning system therefore allows very sensitive control of up to eight climate zones.
[0014] This solution, however, has the structural disadvantage that again the partial air flows are first separated and through own channels directed to a corresponding air chamber each and then are re-united so that the controlled amount of air at the desired temperature is accordingly available at the air outlets.
[0015] In general, the known solutions have the following disadvantages:
[0016] Due to the additional components proposed to be inserted in the air conditioning systems for achieving layering by means of channels or air guiding baffles, more acoustic problems are brought up.
[0017] Moreover, in most cases these solutions are characterized by that they include additional components in form of system parts and elements, which naturally has additional costs and mounting expenditure and accordingly additional maintenance efforts as well, as a consequence.
[0018] Also, from the view of fluid mechanics, the additional inserts in the system lead to increased pressure drop resulting in increased power demand and eventually, increased energy consumption, hence reduced efficiency of the whole motor vehicle.
SUMMARY OF THE INVENTION
[0019] Now, the object of the invention is to provide an air conditioning unit that almost without additional inserts, oriented on demand and functions, provides air flows with the desired temperature at the individual air outlets, while keeping the space requirements of the air conditioning unit very low.
[0020] The problem is solved according to the invention by that the vehicle air conditioning unit is provided with means for cooling and heating air and has a casing with at least three air outlets, whereby as a means for heating the air at least one heating heat exchanger is provided that in its vertical extension has at least one cold air passage, whereby one cold air passage is disposed between two heating paths. As a means for cooling the air, an evaporator is provided that in direction of the air flow is disposed upstream of the heating heat exchanger in such a way that after the heating heat exchanger there is a temperature-layered air flow, the layers of which are wholly or partly assigned directly to the air outlets.
[0021] The concept of the invention is that already due to the arrangement and establishment of the components that control the temperature of the air, i.e. heat exchanger and evaporator, the air conditioning unit is established such that a natural layering according to the requirement profile of the air outlets is already given by design, without additional mixing zones and additional channels being needed.
[0022] The requirement profile of the air outlets defines the temperature of the air flow in the order of a hot air flow to the defroster outlet, a colder air flow to the passenger outlet and the driver outlet, respectively, and a warmer air flow again to the footwell outlet. Eventually, the solution according to the invention realizes the principle that each air outlet more or less has its own heat exchanger that is already is effective due to the arrangement and forced passage of the components in the defined direction from the air inlet at the evaporator to the air outlets after the heating heat exchanger, although in the end the individual heat exchanger zones are combined with each other by function, and thus are established efficiently saving components.
[0023] The concept of the invention is realized by that a heating heat exchanger is used that is equipped with a cold air passage. Hence the cold air is not led past the heat exchanger as in solutions of prior art, but it is led passing through the heat exchanger. Therefore the heat exchanger has been separated, according to the invention, to form several, at least two heating zones between which a cold air passage is provided.
[0024] The heating heat exchanger is designed such that the cold air passage divides the heat exchanging area of the heating heat exchanger in a ratio of 1/3 to 2/3. Alternatively, the cold air passage can also be disposed centrally in the heating heat exchanger, thus dividing the heat exchanging capacity into two parts. Depending on the requirement profile of the air outlets assigned to the air layers, also a ratio of division of the heat exchanging area by the cold air flow(s) adapted to the corresponding requirement profile is possible.
[0025] Usually, the air conditioning device has three outlet planes, one for the footwell region, preferably arranged in the lower area of the device, one for the defroster region in the upper area of the device, and one for the ventilation of the passengers over the dashboard region, arranged mainly centrally seen in side view.
[0026] The division of the heat exchanging area of the heating heat exchanger is chosen such that both hot regions, the defroster region and the footwell region, are assigned each to a heating zone of the heat exchanger so that two heating paths for the hot air flows are defined, which are separated from the cold air layer disposed in the central region between said hot air flows.
[0027] Because of that a layering is established in the air conditioning device that corresponds to the layering of the outlets. Upstream of the heating heat exchanger there is a temperature control door system that controls the air mass flows through both elements of the heat exchanger and through the cold air passage, respectively, in the usual manner. The arrangement of the temperature control system is chosen such that inflow into the cold path and the hot paths as free as possible from losses and noise is achieved. Temperature control is advantageously realized by temperature control doors and/or temperature control slides. Assumed to be particularly preferred is a combination of a temperature control door and a temperature control slide. In a preferred embodiment, a temperature control slide accommodation chamber is provided to accommodate the temperature control slides in a “full-hot position”
[0028] An alternative embodiment is that the heating heat exchanger is provided with several cold air paths. The cold air paths in the heating heat exchanger are preferably established to be thermally insulated from the heating heat exchanger using a frame or the like, in order to keep heat transmission to the cold air flow through the heating heat exchanger as low as possible, or to completely prevent it, respectively.
[0029] Air distribution doors are added immediately at the air outlets in a usual way so that the air flows at the air outlets can be controlled.
[0030] As usual, the heating heat exchanger itself is constructed of side tanks, which are connected through flat pipes. Between the flat tubes fins are established enlarging the heat exchanger surface. The air flow passes the fin structure picking up heat from the heating heat exchanger. In the region of the cold air passages preferably, there are no flat pipes so that a cost-effective embodiment of such a heat exchanger is, in particular, that in a central area, the heat exchanger is not provided with either flat pipes or fins.
[0031] In principle, the heating paths for heating the air flows could also be established using separate heating heat exchangers connected with each other. This embodiment is included in the invention as specified by the concept, but is a more complex and hence more costly solution to be mentioned, however, for the sake of completeness.
[0032] Another advantageous embodiment of the invention is that the heating heat exchanger is provided with additional heaters.
[0033] According to an embodiment of the invention, PTC-heating heat exchangers are used as additional heaters, or the heating heat exchanger itself is established as a PTC-heating heat exchanger. It is particularly comfortable, according to an advantageous embodiment of the invention, that the heating path that corresponds with the bottom outlet, in addition to the heating heat exchanger, is equipped with an additional heater. Often the passengers of the vehicle welcome a slightly increased temperature realized in the footwell zone.
[0034] Another advantageous embodiment of the invention is that in a portion of the cold air passage, a cold air channel entrance is disposed that enables cold air to be tapped of the cold air passage. This cold air channel can directly be run to an outlet of the air conditioning device so that it is possible to provide one or several outlets with an air flow at a defined lower temperature.
[0035] The solution according to the invention has various advantages.
[0036] Because inserts in the air conditioning device are dispensed with, the flow path can be designed more efficient so that the pressure losses of the system are minimized. This results in lower energy consumption.
[0037] Running the cold air path through the heating heat exchanger results in an improved cold air flow compared to the solutions of prior art, because the air can be passed at lower losses and noise.
[0038] Refraining from additional inserts also means reduced components, hence lower material and manufacture costs as well as reduced expenditure for maintenance and repair.
[0039] It is a decisive advantage that the overall size of such an air conditioning device can be reduced compared to other solutions, which is particularly important in the field of vehicle building.
[0040] Further, the natural layering of the individual air flows ensures in an especially advantageous manner that the requirements of automatic control can be met even by the pre-set layering without posing bigger problems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] Further details, features, and advantages of the present invention will become apparent from consideration of the following description when taken in connection with the accompanying drawings in which is shown:
[0042] FIG. 1 is an air conditioning device in central sectional view, with a heating heat exchanger having a cold air passage;
[0043] FIG. 2 is a heating heat exchanger having a cold air passage;
[0044] FIG. 3 is an air conditioning device in central sectional view, with a heating heat exchanger having two cold air passages; and
[0045] FIG. 4 is a PTC-heating heat exchanger having two cold air passages.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0046] In FIG. 1 an air conditioning device is shown in central sectional view.
[0047] According to the concept of the invention, both heating paths and the cold air passage as well are arranged such that they meet the requirements of layering and correspond to the outlet positions. The arrangement of the temperature control system is chosen such that inflow into the cold air path is as free of losses and noise as possible. In a preferred embodiment of the invention three single doors are used that separately control the three air layers of the total flow. In the alternative version shown in FIG. 1 a temperature control slide 5 in conjunction with a temperature control door 15 are used as temperature control elements that are connected to each other via a kinematic mechanism.
[0048] The air conditioning device essentially includes an evaporator 1 and a heating heat exchanger 2 , both arranged in a casing 4 . The casing 4 is provided with three air outlets 7 , 8 , 9 . The direction of the air flow is indicated by the arrow marked with the numeral 3 . In direction of air flow 3 upstream of the heating heat exchanger 2 , there is the temperature control slide 5 and in the lower part, the temperature control door 15 . In its central area, the heating heat exchanger 2 is provided with a cold air passage 12 . Due to the division of the heating heat exchanger 2 by the cold air passage 12 , a heating path 10 is formed in the upper zone of the heating heat exchanger 2 and a heating path 11 is formed in the lower zone of the heating heat exchanger 2 . The heating paths 10 , 11 heat the air that passes through the respective zones of the heat exchanger. The cold air passage 12 enables cold air to pass, which has entered the air conditioning device over the evaporator 1 . The cold air flows via the cold air passage 12 through the heating heat exchanger 2 without picking up a noticeable amount of heat. The air outlets are equipped with air distribution doors 6 . According to the concept of the invention, a layered flow develops due to the segmentation of the heating heat exchanger 2 . The advantageous effect now is that the temperature of the air layers meets the requirement profile of the assigned air outlets 7 , 8 , 9 .
[0049] The air outlet 7 is the defroster outlet where hot air should exit preferably for de-icing the window glasses and keeping them transparent. This hot air develops from a partial air flow of the air that has entered the air conditioning device over the evaporator 1 , where the air first is cooled and dried while the partial air flow is then heated via the heating path 10 of the heating heat exchanger 2 . Hence, this partial air flow is hot and dry.
[0050] At the air outlet 8 , the passenger- or driver outlet, the exiting air must not be too hot as persons often find it uncomfortable when they are hit by too hot air in the chest and face areas. Therefore it is desired that the air layer exiting through the air outlet 8 is not heated to the same extent as the air exiting through the defroster outlet 7 . To this end, in the heating heat exchanger 2 there is the cold air passage 12 . The air cooled in the evaporator 1 first flows through the heating heat exchanger 2 without being heated markedly, then mixing only little with both adjacent hotter air flows. Depending on the requirement profile, heating of this air flow can of course be varied via a corresponding position of the temperature control elements 5 and 15 .
[0051] Finally, at the air outlet 9 , i.e. the bottom outlet for the footwell zone of the vehicle, again hotter air is desired, as passengers welcome this as a rule. The hot air required for this air outlet is available after the air having entered the air conditioning device over the evaporator 1 has been heated over the heating path 11 . The air heated in the heating path 11 as the lowest layer of the air flow eventually flows to the bottom outlet 9 , there exiting from the air conditioning device. In the example of embodiment, an additional heater 19 is installed for additional heating the air for the footwell zone, which exits from the bottom outlet 9 .
[0052] In the example of embodiment, the cold air passage 12 segments the heating heat exchanger into a heat exchanging region for the heating path 10 and a heat exchanging region for the heating path 11 . The accompanying heat exchanging surface is about ⅓ of the capacity of the heating heat exchanger 2 for the heating path 10 , ⅔ of the capacity of the heating heat exchanger 2 for the heating path 11 .
[0053] The temperature control slide and temperature control door 5 and 15 are coupled such that the temperature can be set by means of one actuator. Alternatively, in order to establish a certain layering, the individual doors can be actuated using separate actuating motors, which if necessary can be operated synchronously. The cold air passage 12 is arranged in the heating heat exchanger 2 such that both a layering of the air flow is achieved and, if required, the cold air flow can reach the air outlet 8 almost uninfluenced.
[0054] The cold air passage 12 is separated by a frame not shown from the heating heat exchanger 2 , the frame insulating the cold air from the hot inner walls of the heating heat exchanger 2 and also serving as a stop for the temperature control doors 15 or temperature control slides 5 .
[0055] In FIG. 2 a segmented heating heat exchanger 2 is shown. The heating heat exchanger 2 essentially includes two side tanks 18 that are connected to each other by flat pipes 20 . Fins (not shown) are disposed between the individual flat pipes, the fins enlarging the heat exchanging surface that transmits heat from the heating medium flowing through the flat pipes to the air.
[0056] The heating heat exchanger 2 , in the form shown, is provided with a heating path 10 and a heating path 11 , with a cold air passage 12 in between. The cold air passage 12 is established by that in this area no flat pipes 20 are disposed.
[0057] FIG. 3 an air conditioning unit is shown in central sectional view, which allows achieving an a bit more expensive but also more precise control of the temperatures of the air layers, compared with the embodiment previously described. In this embodiment, apart from the elements that have already been shown and described in FIG. 1 , a heating heat exchanger 2 is disposed that has two cold air passages 12 and 13 . Thus, for the heating heat exchanger 2 three heating paths 10 , 11 , 14 and two cold air passages 12 and 13 follow. Upstream of the heating heat exchanger 2 a temperature control slide 5 is arranged as temperature control element, provided with cut-outs corresponding with the cold air passages 12 and 13 . For accommodation of the temperature control slide 5 , a temperature control slide accommodation chamber 17 is provided in the area of the casing 4 above the heating heat exchanger 2 .
[0058] The temperature control slide 5 makes possible to completely close the heating paths 10 , 11 and 14 , and at the same time, to release the cold air passages 12 and 13 . On the other hand, in the case of maximum heating of the air, the temperature control slide 5 is totally moved in the temperature control slide accommodation chamber 17 of the casing 4 so that the heating paths 10 , 11 and 14 are completely opened, whereas the cold air passages 12 and 13 are closed.
[0059] In FIG. 4 a PTC-heating heat exchanger 2 is shown that, similar to the liquid-based heating heat exchangers, is provided with geometrically equally shaped openings for the cold air passages 12 and 13 , as well as the heating paths 10 , 11 and 14 . The PTC-heating element can also be established as additional heater geometrically corresponding with the heating heat exchanger 2 , in the direction of air flow 3 arranged downstream of the heating heat exchanger 2 . The PTC-heating element essentially includes two headers 16 , between which heat exchanging elements are disposed.
NOMENCLATURE
[0000]
1 evaporator
2 heating heat exchanger
3 direction of air flow
4 casing
5 temperature control slide
6 air distribution doors
7 air outlet, defroster outlet
8 air outlet, passenger-, driver outlet
9 air outlet, bottom outlet
10 heating path
11 heating path
12 cold air passage
13 cold air passage
14 heating path
15 temperature control door
16 header
17 temperature control slide accommodation chamber (pocket)
18 side tank
19 additional heater
20 flat pipes | The invention relates to an air conditioning unit provided with means for cooling and heating air, including a casing with a plurality of air outlets. At least one heating heat exchanger is provided that in its vertical extension has at least one cold air passage whereby, the one cold air passage is disposed between two heating paths. An evaporator is provided, downstream of which in direction of the air flow the heating heat exchanger is disposed, such that after the heating heat exchanger there is a temperature-layered air flow, the layers of which are wholly or partly assigned directly to the air outlets. | 1 |
PRIORITY DOCUMENT
This patent application claims priority of Provisional Patent Application No. 61/978,313 entitled, “Lightweight and thermally efficient LED down light” filed on Apr. 11, 2014.
FIELD OF THE INVENTION
The present invention relates generally to a lightweight LED lighting module with improved thermal efficiency that can be used in retrofit recessed down light can applications or for new down light installations.
BACKGROUND OF THE INVENTION
Incandescent tungsten filament lamps were the first source of light that was created. These incandescent lamps were later used on dimmers that controlled the amount of power going into the lamps to provide dimming of the light output and for energy savings. HID or metal halide lamps and fluorescent lamps were later discovered that offered increased lamp life and brighter outputs over the incandescent lamps. These HID or fluorescent lamps operated with a ballast that first ignited an arc and then limited the power to the lamp to keep the arc operating. Certain HID or fluorescent lamps could be used with special dimming ballasts that could be dimmed for additional energy savings.
More recently, advances in LED brightness and efficacy have allowed LED lamps and LED modules to be developed that could offer even longer lamp life and brighter outputs when properly configured, to compete with HID or fluorescent lamps. A driver is used to provide the correct power to the LEDs either through PWM, constant voltage, or constant current. The LED lamps and LED modules could be hard-wired directly to the driver in an internal or external configuration, or can be eliminated with the use of dimmable AC LEDs and special IC chips. The drivers could be made dimmable for use with the already inherent nature of energy savings provided by the LEDs.
For new designs and ease of retrofits, it is desirable to have one LED light or LED module that can be installed into existing incandescent, compact fluorescent or HID fixtures to ultimately create a longer lasting and energy efficient LED light fixture.
The present invention provides for an LED light or LED module that allows an end user to have a retrofit LED lamp option to existing halogen, compact fluorescent, or HID fixtures. The same present invention also provides for an LED light or LED module option that allows an end user to readily install a new LED light or LED module as a recessed down light for new installations.
Lastly, the present invention will provide for a thermally efficient, better, and lightweight LED light that can be installed in multiple applications including new recessed down light installations with very low ceiling height clearances.
DESCRIPTION OF THE RELATED ART
Companies including Lighting Science Group and Commercial Electric for Home Depot among many others, offer LED down light fixtures that can be use in existing fixtures as retrofits or as an LED fixture in new recessed down light installations. However, all of these models use external bulky and heavy heat sinks attached to a separate plate positioned at the rear of the fixtures to provide cooling for the LEDs. The additional heat sinks add extra and unnecessary weight, and additional cost to the fixtures. The height of the heat sink in some fixtures also makes the LED down light fixtures higher than necessary, thereby preventing its use in very low profile ceiling or wall mount applications. Some background on a typical two piece configuration for a recessed LED down light can be found in U.S. Pat. No. 8,201,968 issued to Maxik et al. titled, “Low Profile Light” and assigned to Lighting Science Group Corporation, and also in U.S. Pat. No. 8,672,518 issued to Boomgaarden et al. titled, “Low Profile Light and Accessory Kit for the same” that is also assigned to Lighting Science Group Corporation.
The present invention is an improvement over other inventions. It uses a single unitary metal dish preferably made of aluminum for better thermal conductivity and makes the overall LED fixture more lightweight. The metal dish can be made from different manufacturing processes including, but not limited to deep draw, stamping, spinning, metal forming, and other methods for making this multipurpose combination heat sink and trim assembly for the mounting of an LED board or LED arrays. This metal dish eliminates the need for having a separate trim ring and heat sink, thereby reducing overall weight and cost of the LED light or LED module. Having a single piece also allows for better thermal conductivity of the LED board or LED arrays where heat from the LEDs are cooled directly by the metal dish into the trim ring of the LED light or LED module without the need to go through multiple surfaces offering better and more efficient thermal transfer. In addition, the metal dish also serves as the means for mounting the entire LED light or LED module to a junction box for new installation applications, or the attachment of removable metal springs or clips and brackets for retrofit applications into existing lighting down light can fixtures.
The device of the present invention consists primarily of a main metal dish. The main metal dish serves multiple purposes. Primarily, it serves as an immediate surface in which to mount an LED printed circuit board or a COB or chip-on-board LED module array, and serve as a thermally conductive heat sink. The circuit board contains at least one string of LEDs or LED arrays. Likewise the COB may contain at least one string of LEDs or LED arrays. The second purpose is to provide a decorative trim ring for LED light fixture for retrofit and new installation applications. Lastly, the main metal dish contains screw clearance holes for mounting to different size junction boxes for new installations, and also has provisions on it for the mounting of removable brackets, clips, and springs, or for the attachment of only springs provided for retrofitting the complete LED light assembly into an existing recessed down light can. Provisions are also provided on the main metal dish for the mounting of an LED light engine, an optional external driver, and a diffusion lens.
The preferred embodiment of the present invention consists of a main combination heat sink and trim ring metal dish, removable mounting clips or springs, LED light engine, diffusion lens, and an external AC to DC dimmable LED driver.
An alternate embodiment of the present invention consists of a main combination heat sink and trim ring metal dish, removable mounting clips or springs, dimmable AC LED light engine with internal controller, and a diffusion lens.
SUMMARY OF THE INVENTION
The device of the present invention includes in its most basic form, a main metal dish, removable springs, an LED light engine, an optional LED driver, and a diffusion snap-in lens.
The preferred embodiment is therefore a dimmable device that has a. combination heat sink and trim ring main metal dish for mounting an LED circuit board or LED light engine to one side of the dish. The circuit board contains at least one string of LEDs or LED arrays. Likewise the COB may contain at least one string of LEDs or LED arrays. Removable brackets containing springs or separate spring clips are attached to the opposite side of the dish for allowing the LED fixture to be installed into an existing down light can in a retrofit application. For new installations of the LED fixture mounted straight to a junction box, the removable brackets containing the springs or separate spring clips are not used. An optional AC to DC dimmable driver is mounted on the same side as the removable brackets containing springs or separate spring clips. This external LED driver is then connected to the LED light engine consisting of at least one string of LEDs or LED arrays mounted to a circuit board, or a chip-on-board (COB) LED array. Lastly, a separate diffusion lens made preferably out of plastic to maintain an overall lower weight to the LED fixture is attached to the main metal dish on the same side as the LED light engine to protect the LEDs from dust and damage and also to diffuse the light that is emitted out the front of the LEDs mounted to a circuit board.
The alternate embodiment is therefore a dimmable device that has a. combination heat sink and trim ring main metal dish for mounting a dimmable AC LED circuit board or dimmable AC LED light engine to one side of the dish. The circuit board contains at least one string of AC LEDs or AC LED arrays. Likewise the AC COB may contain at least one string of LEDs or LED arrays. Removable brackets containing springs or separate spring clips are attached to the opposite side of the dish for allowing the dimmable AC LED fixture to be installed into an existing down light can in a retrofit application. For new installations of the dimmable AC LED fixture mounted straight to a junction box, the removable brackets containing the springs or separate spring clips are not used. No external driver is used with a dimmable AC LED circuit board. Instead, an on-board controller or ASIC or other means to control the LEDs including transistors or MOSFET devices may be used to operate the LEDs directly. The elimination of an external LED driver removes added weight and cost, and provides for an overall lower profile LED light in general. Lastly, a separate diffusion lens made preferably out of plastic to maintain an overall lower weight to the dimmable AC LED fixture is attached to the main metal dish on the same side as the dimmable AC LED light engine to protect the dimmable AC LEDs from dust and damage and also to diffuse the light that is emitted out the front of the dimmable AC LEDs mounted to a circuit board.
OBJECT OF THE INVENTION
It is an object of the present invention to provide a dimmable device that will work in a retrofit and in a new installation application.
It is another object of the present invention to provide a dimmable device that will fit into most existing down light can fixtures as a direct retrofit.
It is yet another object of the present invention to provide a dimmable device that can be installed into a wide variety of different junction boxes for new installations.
It is also another object of the present invention to provide a dimmable device that will provide a very lightweight LED light option for both retrofit and new installations.
It is also yet another object of the present invention to provide a dimmable and thermally efficient LED light option for both retrofit and new installations.
It is a final object of the invention to provide a dimmable device that will have a lower installed height profile for installation in tight overhead ceiling or wall installations.
While the novel features of the invention are set forth particularly in the appended claims, the invention, both as to organization and content, will be better understood and appreciated along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the preferred embodiment of the present invention of a 4″ LED light in front, side, and isometric views showing the main metal plate, removable mounting bracket and springs, LED circuit board (not shown), optional external dimmable LED driver, and a diffusion lens.
FIG. 2 shows the preferred embodiment of the present invention of a 4″ LED light in back, side, and isometric views showing the main metal plate, removable mounting bracket and springs, LED circuit board (not shown), optional external dimmable LED driver, and a diffusion lens.
FIG. 3 shows an alternate embodiment of the present invention of a 4″ LED light in front, sides, and isometric views showing the main metal plate, removable mounting bracket and springs, dimmable AC LED circuit board (not shown), and a diffusion lens.
FIG. 4 shows an alternate embodiment of the present invention of a 4″ LED light in back, sides, and isometric views showing the main metal plate, removable mounting bracket and springs, dimmable AC LED circuit board (not shown), and a diffusion lens.
FIG. 5 shows a typical diffusion lens that can be used in both embodiments of the present inventions of a 4″ LED light as shown in FIGS. 1, 2, 3, and 4 .
FIG. 6 shows the preferred embodiment of the present invention of a 6″ LED light in front, side, and isometric views showing the main metal plate, removable mounting bracket and springs, LED circuit board (not shown), optional external dimmable LED driver, and a diffusion lens.
FIG. 7 shows the preferred embodiment of the present invention of a 6″ LED light in back, side, and isometric views showing the main metal plate, removable mounting bracket and springs, LED circuit board (not shown), optional external dimmable LED driver, and a diffusion lens.
FIG. 8 shows an alternate embodiment of the present invention of a 6″ LED light in front, sides, and isometric views showing the main metal plate, removable mounting bracket and springs, dimmable AC LED circuit board (not shown), and a diffusion lens.
FIG. 9 shows an alternate embodiment of the present invention of a 6″ LED light in back, sides, and isometric views showing the main metal plate, removable mounting bracket and springs, dimmable AC LED circuit board (not shown), and a diffusion lens.
FIG. 10 shows a typical diffusion lens that can be used in both embodiments of the present inventions of a 6″ LED light as shown in FIGS. 6, 7, 8, and 9 .
FIG. 11 shows an engineering testing record of the thermals done on the LEDs of a circuit board installed in a 4″ LED light of the preferred embodiment of the present invention as shown in FIGS. 1 and 2 .
FIG. 12 shows an engineering testing record of the thermals done on the LEDs of a circuit board installed in a 6″ LED light of the preferred embodiment of the present invention as shown in FIGS. 6 and 7 .
The foregoing has outlined rather broadly, the features and technical advantages of the present invention, so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art will appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. Those skilled in the art will also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.
DETAILED DESCRIPTION
Although the present invention has been described in terms of the presently preferred embodiments, it is to be understood that such disclosure is not to be interpreted as limiting. Various alterations and modifications will no doubt become apparent to those skilled in the art after having read the above disclosure. Accordingly, it is intended that the appended claims be interpreted as covering all alterations and modifications as fall within the true spirit and scope of the invention.
FIG. 1 shows the preferred embodiment of the present invention of a 4″ LED light 10 in front, side, and isometric views. LED light 10 consists of a main metal dish 15 with four mounting clips 20 center around the periphery of metal dish 15 . Clips 20 are preferably made of steel spring material and fastened to metal dish 15 . An LED circuit board or COB 25 (not shown) is attached to the opposite side of metal dish 15 . Power wires from LED circuit board or COB 25 (not shown) are fed through a clearance passage hole 30 to the back of metal dish 15 for direct connection to an external LED driver 35 . Mounting screw clearance holes 40 are provided on metal dish 15 for attaching LED light 10 to a standard junction box (not shown). Lastly, diffusion lens 45 (not shown) is attached to the front of metal dish 15 to cover and protect LED circuit board or COB 25 (not shown) from dust and damage and provides the proper optics to project an even and diffused light from LED light 10 .
FIG. 2 shows the preferred embodiment of the present invention of a 4″ LED light 10 in back, side, and isometric views. LED light 10 consists of a main metal dish 15 with four mounting clips 20 centered on the periphery of metal dish 15 . Clips 20 are preferably made of steel spring material and fastened to metal dish 15 . An LED circuit board or COB 25 (not shown) is attached to the opposite side of metal dish 15 . Power wires from LED circuit board or COB 25 (not shown) are fed through a clearance passage hole 30 to the back of metal dish 15 for direct connection to an external LED driver 35 . Mounting screw clearance holes 40 are provided on metal dish 15 for attaching LED light 10 to a standard junction box (not shown). Lastly, diffusion lens 45 is attached to the front of metal dish 15 to cover and protect LED circuit board or COB 25 (not shown) from dust and damage and provides the proper optics to project an even and diffused light from LED light 10 .
FIG. 3 shows an alternate embodiment of the present invention of a 4″ LED light 50 in front, side, and isometric views. LED light 50 consists of a main metal dish 55 with four mounting clips 60 centered on the periphery of metal dish 55 . Clips 60 are preferably made of steel spring material and fastened to metal dish 55 . A dimmable AC LED circuit board or AC COB 65 (not shown) is attached to the opposite side of metal dish 55 . Power wires from dimmable AC LED circuit board or AC COB 65 (not shown) are fed through a clearance passage hole 70 to the back of metal dish 55 for direct connection to AC power (not shown). Mounting screw clearance holes 75 are provided on metal dish 55 for attaching LED light 50 to a standard junction box (not shown). Lastly, diffusion lens 80 (not shown) is attached to the front of metal dish 55 to cover and protect dimmable AC LED circuit board or AC COB 65 (not shown) from dust and damage, and provides the proper optics to project an even and diffused light from LED light 50 .
FIG. 4 shows an alternate embodiment of the present invention of a 4″ LED light 50 in back, side, and isometric views LED light 50 consists of a main metal dish 55 with four mounting clips 60 center around the periphery of metal dish 55 . Clips 60 are preferably made of steel spring material and fastened to metal dish 55 . A dimmable AC LED circuit board or AC COB 65 (not shown) is attached to the opposite side of metal dish 25 . Power wires from dimmable AC LED circuit board or AC COB 65 (not shown) are fed through a clearance passage hole 70 to the back of metal dish 55 for direct connection to AC power (not shown). Mounting screw clearance holes 75 are provided on metal dish 55 for attaching LED light 50 to a standard junction box (not shown). Lastly, diffusion lens 80 is attached to the front of metal dish 55 to cover and protect dimmable AC LED circuit board or AC COB 65 (not shown) from dust and damage, and provides the proper optics to project an even and diffused light from LED light 50 .
FIG. 5 shows a typical diffusion lens 45 , 80 that can be used in both preferred and alternate embodiments of the present inventions of a 4″ LED light 10 , 50 as shown in FIGS. 1, 2, 3, and 4 . Diffusion lens 45 , 80 is shown with a front convex side 85 and a back concave side 90 . Back concave side 90 faces the LEDs (not shown) and protects them. Diffusion lens 45 , 80 is preferably made out of a plastic material to be lightweight and will diffuse the light beam projected out by the LEDs (not shown) from front convex side 85 . There is also provided on diffusion lens 45 , 80 mounting tabs 95 for secure and tool free attachment of the diffusion lens 45 , 80 to LED light 10 , 50 . It should be noted that someone skilled in the arts can use other means for attaching the diffusion lens 45 , 80 to the LED light 10 , 50 besides incorporating mounting tabs 95 including, but not limited to glue, adhesive, friction lock, screw and thread, tape, press fit, etc.
FIG. 6 shows the preferred embodiment of the present invention of a 6″ LED light 100 in front, side, and isometric views. LED light 100 consists of a main metal dish 105 with two sets of mounting brackets 110 and springs 115 each centered on the periphery of metal dish 105 . Mounting brackets 110 are made of metal and springs 115 are preferably made of spring steel attached to mounting brackets 110 and all fastened to metal dish 105 . An LED circuit board or COB 120 (not shown) is attached to the opposite side of metal dish 105 . Power wires from LED circuit board or COB 120 (not shown) are fed through a clearance passage hole (not shown) to the back of metal dish 105 for direct connection to an external dimmable LED driver 125 . Mounting screw clearance holes 130 are provided on metal dish 105 for attaching LED light 100 to a standard junction box (not shown). Lastly, diffusion lens 135 is attached to the front of metal dish 105 to cover and protect LED circuit board or COB 120 (not shown) from dust and damage, and provides the proper optics to project an even and diffused light from LED light 100 .
FIG. 7 shows the preferred embodiment of the present invention of a 6″ LED light 100 in back, side, and isometric views. LED light 100 consists of a main metal dish 105 with two sets of mounting brackets 110 and springs 115 each centered on the periphery of metal dish 105 . Mounting brackets 110 are made of metal and springs 115 are preferably made of spring steel attached to mounting brackets 110 and all fastened to metal dish 105 . An LED circuit board or COB 120 (not shown) is attached to the opposite side of metal dish 105 . Power wires from LED circuit board or COB 120 (not shown) are fed through a clearance passage hole (not shown) to the back of metal dish 105 for direct connection to an external dimmable LED driver 125 . Mounting screw clearance holes 130 are provided on metal dish 105 for attaching LED light 100 to a standard junction box (not shown). Lastly, diffusion lens 135 is attached to the front of metal dish 105 to cover and protect LED circuit board or COB 120 (not shown) from dust and damage, and provides the proper optics to project an even and diffused light from LED light 100 .
FIG. 8 shows an alternate embodiment of the present invention of a 6″ LED light 140 in front, side, and isometric views. LED light 140 consists of a main metal dish 145 with two sets of mounting brackets 150 and springs 155 each centered on the periphery of metal dish 145 . Mounting brackets 150 are made of metal and springs 155 are preferably made of spring steel attached to mounting brackets 150 and all fastened to metal dish 145 . A dimmable AC LED circuit board or AC COB 160 (not shown) is attached to the opposite side of metal dish 145 . Power wires from dimmable AC LED circuit board or AC COB 160 (not shown) are fed through a clearance passage hole (not shown) to the back of metal dish 145 for direct connection to AC power (not shown). Mounting screw clearance holes 165 are provided on metal dish 145 for attaching LED light 140 to a standard junction box (not shown). Lastly, diffusion lens 170 is attached to the front of metal dish 145 to cover and protect dimmable AC LED circuit board or AC COB 160 (not shown) from dust and damage, and provides the proper optics to project an even and diffused light from LED light 140 .
FIG. 9 shows an alternate embodiment of the present invention of a 6″ LED light 140 in back, side, and isometric views. LED light 140 consists of a main metal dish 145 with two sets of mounting brackets 150 and springs 155 each centered on the periphery of metal dish 145 . Mounting brackets 150 are made of metal and springs 155 are preferably made of spring steel attached to mounting brackets 150 and all fastened to metal dish 145 . A dimmable AC LED circuit board or AC COB 160 (not shown) is attached to the opposite side of metal dish 145 . Power wires from dimmable AC LED circuit board or AC COB 160 (not shown) are fed through a clearance passage hole (not shown) to the back of metal dish 145 for direct connection to AC power (not shown). Mounting screw clearance holes 165 are provided on metal dish 145 for attaching LED light 140 to a standard junction box (not shown). Lastly, diffusion lens 170 is attached to the front of metal dish 145 to cover and protect dimmable AC LED circuit board or AC COB 160 (not shown) from dust and damage, and provides the proper optics to project an even and diffused light from LED light 140 .
FIG. 10 shows a typical diffusion lens 135 , 170 that can be used in both preferred and alternate embodiments of the present inventions of a 6″ LED light 100 , 140 as shown in FIGS. 6, 7, 8, and 9 . Diffusion lens 135 , 170 is shown with a front convex side 175 and a back concave side 180 . Back concave side 180 faces the LEDs (not shown) and protects them. Diffusion lens 135 , 170 is preferably made out of a plastic material to be lightweight and will diffuse the light beam projected out by the LEDs (not shown) from front convex side 175 . There is also provided on diffusion lens 135 , 170 mounting tabs 185 for secure and tool free attachment of the diffusion lens 135 , 170 to LED light 100 , 140 . It should be noted that someone skilled in the arts can use other means for attaching the diffusion lens 135 , 170 to the LED light 100 , 140 besides incorporating mounting tabs 185 including, but not limited to glue, adhesive, friction lock, screw and thread, tape, press fit, etc.
FIG. 11 shows an engineering testing record of the thermals done on the LED circuit board installed in a 4″ LED light 10 , 50 of the preferred embodiment of the present invention as shown in FIGS. 1 and 2 . The LEDs used in the test are 5630 mid-power LEDs from Seoul Semiconductor with an operational temperature rating of 70.0 deg. C. Note that any industry 5630 or similar LED package can be used and should produce similar results. From the test data, one can see that the maximum temperature measured at the LED was 64.7 degrees Celsius at an ambient temperature of 23.7 degrees C. Normalized to 25.0 deg. C., the maximum LED temperature for the 4″ LED light 10 , 50 is 66.0 deg. C., which is below the 70.0 deg. C. rated operating temperature of the Seoul Semiconductor 5630 mid-power LEDs.
FIG. 12 shows an engineering testing record of the thermals done on the LED circuit board installed in a 6″ LED light 100 , 140 of the preferred embodiment of the present invention as shown in FIGS. 6 and 7 . The LEDs used in the test are 5630 mid-power LEDs from Seoul Semiconductor with an operational temperature rating of 70.0 deg. C. Note that any industry 5630 or similar LED package can be used and should produce similar results. From the test data, one can see that the maximum temperature measured at the LED was 66.4 degrees Celsius at an ambient temperature of 23.8 degrees C. Normalized to 25.0 deg. C., the maximum LED temperature for the 6″ LED light 100 , 140 is 67.6 deg. C., which is below the 70.0 deg. C. rated operating temperature of the Seoul Semiconductor 5630 mid-power LEDs.
It will be understood that various changes in the details, materials, types, values, and arrangements of the components that have been described and illustrated in order to explain the nature of this invention may be made by those skilled in the art without departing from the principle and scope of the invention as expressed in the following claims. | A lightweight and thermally efficient LED lighting module is disclosed for recessed down light can retrofits, or as new down light installations mountable to different size junction boxes consisting of a combination heat sink and trim ring unitary metal dish for the attachment of at least one LED array mounted to a circuit board, or at least one chip-on-board or COB LED array, further including at least two removable springs or clips, junction box mounting screw clearance holes, an optional external dimmable LED driver, and a diffusion lens cover installed to the front of the LED lighting module. | 5 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 12/658,702 filed Feb. 12, 2010, which claims the 5 benefit of U.S. Provisional Patent Application No. 61/207,709, filed Feb. 13, 2009; each of which are incorporated herein by reference in their entirety for all purposes.
FIELD OF THE INVENTION
[0002] The present invention relates generally to fertilizers. More specifically, the invention relates to unmanipulated manure from confined animal feeding operations (CAFOs) and manure-based fertilizers, and to the use of a urea formaldehyde polymer based additive for manure-based fertilizers that reduces odor.
BACKGROUND OF THE INVENTION
[0003] According to municipalities, government agencies, environmentalists and the public in general, odor and potential pollution sources emanating from livestock, for example, hog, dairy, feedlot and poultry, facilities are the main issues that the livestock industry needs to address in order to sustain its development. The most intense source of odor from livestock facilities occurs during manure handling in barns, feed lots, hog confinement buildings, poultry houses, lagoons, litter/manure piles and during land application.
[0004] There are numerous known methods for treating manure including 1) mechanical separation, 2) aerobic treatment; 3) anaerobic treatment; 4) composting; 5) filtration, osmosis and ultrafiltration processes; 6) drying and fertilizers production; 7) biological treatment; and 8) flotation processes. The present invention relates to additives for manure to treat and reduce odor.
[0005] U.S. Pat. No. 1,915,240 teaches a sewage purification method which comprises mixing lime and ferric chloride with raw sewage, which deodorizes the waste and causes floc formation. The floc is then oxidized and sterilized before being allowed to settle for subsequent removal and dewatering.
[0006] U.S. Pat. Nos. 3,619,420 and 3,640,820 teach a sewage treatment process wherein treated sludge is converted to an active substance by heat treatment and returned to the sewage treatment tank, thereby improving the operational efficiency of the method.
[0007] U.S. Pat. No. 4,309,291 teaches a method of continuous flow flocculation and clarification wherein waste water is flocculated by subjecting the mixture to continuous, turbulent flow to and from a settling tank. Clarified effluent and settled flocculent are continuously discharged from the settling tank.
[0008] U.S. Pat. No. 4,111,800 teaches a process for treating municipal solid waste and raw sewage sludge wherein municipal waste is mixed with cellulose-containing solid waste.
[0009] U.S. Pat. No. 4,180,459 teaches a process of making agricultural products from organic sewage sludge comprising treating sewage sludge with FeCI3 and CaO from various sources, preferably from sugar refining for flocculation. It is of note that the sewage sludge is characterized as “acidic conditioned sludge” having a pH of between 3.0-5.7.
[0010] U.S. Pat. No. 4,209,393 teaches using coal as a sewage sludge additive rather than activated carbon.
[0011] U.S. Pat. No. 4,212,732 teaches a raw liquid waste treatment process wherein ash and activated carbon are added to raw sewage to promote settling of flocculent.
[0012] U.S. Pat. No. 4,670,158 teaches a method of wastewater treatment wherein lime and phosphoric acid are added to wastewater to promote flocculation. In this method, the pH of the wastewater is adjusted to be within 7.0-10.0, preferably 8.5-9.0 with phosphoric acid.
[0013] U.S. Pat. No. 5,698,110 teaches a deodorizing composition for treating animal waste comprising a mixture of lime and cellulose so that the waste can subsequently be used as fertilizer.
[0014] U.S. Pat. No. 5,897,785 teaches a process for treating animal waste wherein waste is diluted with water and exposed to radiation to eliminate pathogens. High charge, cationic polymers are then added to the waste such that polymerized solids are formed which are then separated from the waste.
[0015] U.S. Pat. No. 5,958,758 teaches a process for treating animal waste wherein sulfide utilizing bacteria are added to the waste followed by the addition of organic digesting bacteria and lytic enzymes.
[0016] U.S. Pat. No. 6,033,570 teaches a process for the treatment of liquid hog manure in which cellulosic material is added to promote removal of solids from the liquid.
[0017] U.S. Pat. Nos. 6,039,875 and 6,214,230 teach the use of bacterially-generated polymers as coagulants for the removal of suspended solids from wastewater.
[0018] U.S. Pat. Publication 2006/0108291 discloses a method of treating manure with lime and coagulating agents.
SUMMARY OF THE INVENTION
[0019] The present invention is a method of odor control comprising applying a urea formaldehyde polymer additive to manure in an amount sufficient to reduce or eliminate odor. More specifically, the present invention is a method of odor control comprising applying a urea formaldehyde polymer additive to manure, wherein the polymer optionally contains NBPT and/or DCD. The polymer, and the polymer optionally containing NBPT and/or DCD can be a dry solid, or it can be suspended in a liquid and applied to unmanipulated liquid or solid manure.
DETAILED DESCRIPTION OF THE INVENTION
[0020] All percentages are by weight unless otherwise indicated. The additive of the present invention is a urea formaldehyde polymer (UFP) which may be a polymethyl urea resin. The UFP has approximately about 1.0 to 0.01 wt. % reactive methylol groups. The preferred UFP is marketed as PERGOPAK M® 2, a trademark of Albemarle Corporation, which contains from about 10 to 15% water and has about 0.6% reactive methylol groups. It has primary particles of 0.1 to 0.15 micrometers, forming agglomerates of 3.5 to 6.5 micrometers diameter on average. Alternatively, the UFP is the unrefined precursor to PERGOPAK M® 2, sometimes referred to as “the filter cake”, and contains from about 40 to 80 wt. % water. When the UFP is used in an aqueous fertilizer formulation, based on the dry weight of the UFP, the amount of UFP is from about 0.01 to about 12 wt. %, and more preferably in the range of about 0.01 to 1.2 wt. %. If the filter cake is used, greater amounts by weight must be used to achieve the desired results, because of the higher water content of the UFP filter cake.
[0021] Optionally, the UFP can be used as a solid urea fertilizer with an aqueous urea formaldehyde (UF) solution or mixture. An example of an aqueous UF solution is UF85, which is a commercially-available solution containing about 25 wt. % urea, about 60 wt. % formaldehyde, and about 15% water, available under the trademark STA-FORM 60®. The aqueous UF solution can be present in the solid urea fertilizer in the range of about 0.01 to 10.0 wt. %. Preferably, the aqueous UF solution or mixture is present in the range of about 0.1 to 1.0 wt. %. When both the UFP and the UF mixture or solution are used, the ratio of the two can range from about 2:1 to 1:100 UFP to UF mixture or solution.
[0022] The solid, flowable UFP can be treated with a urease inhibitor, such as N-(nbutyl) thiophosphoric triamide (NBPT), a nitrification inhibitor, such as dicyandiamide (DCD), herbicides, pesticides, micronutrients, etc., before or after combining with the urea source. Alternatively, additional components can be added after the UFP has been combined with the urea source, before granulating the product. Optionally, an aqueous UF solution or mixture may be added to the solid, flowable UFP before granulation.
[0023] The additive of the present invention may be a fluid fertilizer composition comprising an aqueous solution of urea or urea ammonium nitrate (UAN), NBPT and DCD. The NBPT is incorporated into the fluid fertilizer composition by preparing a dry flowable additive by coating a dry UFP with a concentrated solution of NBPT in a liquid amide solvent, such as an N-alkyl pyrrolidone. The NBPT is present in the amount of about 0.40 to about 7.0 wt. %. The UFP is present in the range of about 3 to 15 wt. %. Optionally, solid DCD is blended with this dry mixture to further coat the polymer, in the range of about 40 to 85 wt. %. Prior to application, the dry additive is blended with aqueous urea or urea ammonium nitrate (UAN) at the level of from about 0.25 to 1.5 wt. % to form the fluid urea-containing fertilizer composition. The balance of the composition consists primarily of water; an N-alkyl pyrrolidone may also be present in small quantities. The composition may optionally also contain a suspending agent, such as clay, as well as other additives, such as a herbicide, a dye, an NBPT stabilizer, or a micronutrient.
[0024] Commercially available products that are suitable as odor control additives are Agrotain® Plus and Agrotain® DC, a trademark of Agrotain International L.L.C. Both products are solids that contain UFP and NBPT, or a combination of UFP, NBPT and DCD. Their compositions are:
Agrotain® DC:
NBPT 59-61% UFP 39-40% Dye 0.1%
Agrotain® Plus
NBPT 6.41% DCD 81.435% UFP 12.055% Dye 0.1%
[0034] They can be applied neat, or they can be applied after mixing with water, UAN, other fertilizer components or additional solvents.
EXAMPLES OF THE INVENTION
[0035] The following examples are to illustrate the invention, and are not to limit the scope of the claims in any manner.
[0036] In a field test, 240 pounds of Agrotain® Plus (a NBPT, DCD and UFP mixture) were added to 1000 gallons of water. This mixture was added to 810 tons of unmanipulated swine manure. This is an application rate of 0.0147 wt. % for Agrotain® Plus. Breaking down the Agrotain® Plus down into individual components yields an application rate of 0.0009 wt. % for UFP, an application rate of 0.012% of DCD, and an application rate of 0.0009 wt. % NBPT. After application of Agrotain® Plus, a marked reduction of odor was noted.
[0037] In the following laboratory-administered test, the additives, below, were mixed with hog manure (wet) at an application rate of 0.009 wt. % for UFP, 0.12 wt. % for DCD, and 0.009 wt. % for NBPT. The resulting mixtures were evaluated for odor control by a blind sniff test. The results of the test are given in Table 1, below.
[0038] The application rate is from about 0.1 to about 0.0001 wt. % for the UFP to the manure. Preferably, the application rate is from about 0.01 to about 0.0005 wt. % UFP to manure.
[0000]
TABLE 1
The Effect of Additives on Odor
Additive
UFP
NBPT
DCD
Reduced Odor
Agrotain ® Plus
Yes
Yes
Yes
Yes
Agrotain ® DC
Yes
Yes
No
Yes
PERGOPAK M ® UFP
Yes
No
No
Yes
PERGOPAKM ®
Yes
No
No
Yes
Filtercake UFP
Control—no additive
No
No
No
No | A method of odor control comprising applying a urea formaldehyde polymer additive to manure in an amount sufficient to reduce or eliminate odor, wherein the polymer optionally contains NBPT and/or DCD, where the polymer can be a dry solid, or it can be suspended in a liquid and applied to unmanipulated liquid or solid manure. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to a lock fitted to a door and comprising a bolt movable in a straight line between an extended position and a retracted position, means for urging the bolt to its extended position, means for returning the bolt from its extended position to its retracted position, movably coupled to the bolt, a combination disk, comprising a notch and stop means, mounted for rotation on a shaft, a drive disk mounted for rotation on said shaft comprising stop means cooperating with those of the combination disk in a given relative angular position of these disks, and first means for cooperating with said bolt traction means, means for rotating the drive disk, second means for cooperating with said bolt traction means, adapted so as to be received in said notch in a given angular position of the combination disk, obtained by actuating said operating means in accordance with a coded combination, these second means being movable between a position in which they are situated outside the notch and hold the bolt traction means away from the drive disk and a position in which they are situated in the notch and allow cooperation between the bolt traction means and said first means of the drive disk, the bolt then being able to be moved to its retracted position by rotation of the drive disk.
A lock of this type is known more particularly from the document US-A-4 147 045 and operates satisfactorily.
However, it reveals a few drawbacks in use.
In such a lock, the bolt is held in a retracted position by the user who immobilizes the means for operating the drive disk, for example an operating handle. Since the bolt traction means cooperate with the drive disk, they are prisoners of this latter and effectively retain the bolt in the retracted position.
At this stage, the authorized user may block the operating handle by any appropriate means for preventing subsequent closure of the lock and thus avoid having to dial the coded combination the next time he accedes to the door.
In addition, when a finger is provided for scrambling the combination disk, mounted on the bolt for striking the combination disk when the bolt is extended, the user may try to partially neutralize the scrambling effect by braking the movement of the operating handle when it returns to an angular position corresponding to closure of the door, namely by braking the movement of the bolt traction means.
SUMMARY OF THE INVENTION
The problem which the invention attempts to solve is then that of separating the operating handle from the bolt once the lock has been opened.
This problem is solved by providing in the lock means adapted for locking the bolt in its retracted position, means for moving the bolt traction means away from the drive disk when the bolt is in the retracted position, and means adapted for unlocking the bolt once the door has been opened then closed again.
Advantageously, the bolt locking means comprise a rocking lever mounted for pivoting in the bolt and returned resiliently towards the bolt, and stop means mounted on the rocking lever and adapted for cooperating with stop means provided on the bolt, and said bolt unlocking means comprise a pusher mounted for pivoting on the rocking lever and adapted for cooperating with a door casing or a mobile keeper during closure of the door so as to cause the rocking lever to pivot so as to move said stop means of the rocking lever away from the bolt.
Advantageously, said means for moving away the bolt traction means comprise a finger mounted for pivoting on the bolt, a spring mounted fixedly in the lock and adapted for cooperating with the finger when the bolt is in the retracted position, sO as to return the finger in a direction of rotation in which this latter moves said bolt traction means away from the drive disk.
Advantageously, the lock comprises an auxiliary bolt movable in a straight line between an extended position and a retracted position and means for urging it to its retracted position said drive disk being in contact with the auxiliary bolt and adapted for cooperating therewith so that, with said bolt in the retracted position, the auxiliary bolt is in its extended position if the drive disk is in an angular position in which it cooperates with said bolt traction means and the auxiliary bolt is in its retracted position in the opposite case.
Advantageously, the lock comprises scrambling means for modifying randomly the angular position of the combination disk on closure of the door, these scrambling means comprising a finger mounted on the bolt so as to be able to pivot parallel thereto and be urged towards the combination disk, said finger penetrating into said notch in the combination disk when the bolt is in the retracted position and driving the combination disk over a random angular portion when the bolt moves to its extended position.
BRIEF DESCRIPTION OF THE DRAWINGS
The following description is relative to a preferred but non limitative embodiment with reference to the accompanying drawings.
FIG. 1a is an exploded perspective view of a first portion of the lock.
FIG. 1b is an exploded perspective view of a second portion of the lock,
FIGS. 2a and 2b are top views of the lock in the closed position,
FIGS. 3a and 3b are views corresponding to FIGS. 2a, 2b when the lock is in the open position,
FIGS. 4a and 4b are views corresponding to FIGS. 2a, 2b when the combination allowing opening of the lock has been made,
FIGS. 5 to 7 are cross sectional views through lines V--V, VI--VI, VII--VII of FIGS. 2a or 2b, FIG. 8 is a top view showing the parts visible in FIGS. 2a or 2b,
FIG. 9 is a perspective view of the bolt of the traction hook and of the scrambler, seen from their face not visible in FIG. 1a,
FIG. 10 is a perspective view of the lock cooperating with a door closure bar mechanism,
FIGS. 11 and 12 are top views of a variant of the lock, in two different operating positions, and
FIG. 13 is a perspective view of an auxiliary bolt used in this variant.
To help understanding, FIGS. 2a, 3a, 4a only show the bottom-most parts of the lock situated in the lock case, whereas FIGS. 2b, 3b, 4b only show the other more outwardly situated parts in the case of the lock.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The lock shown in the figures comprises a parallelepipedic case 1 formed of a bottom 2 and four sidewalls 3, 4, 5 , 6. As shown in the figures, the case is oriented in use so that its bottom 2 and its two opposite sidewalls 3, 5 are vertical. The vertical wall 3 comprises two rectangular apertures 7, 8 disposed at the side of each other and extending vertically.
Bottom 2 has, in three of its corners, a hole 9, 10 and 11 for fixing to a door and, in its central part, a hole 12. It further has a pluralitY of posts 13 to 19 extending perpendicularly and several studs 20 to 22, post 19 having a collar 19a at its base.
A reciprocating assembly 30 comprises a plate bent into an L shape so as to define two vertical faces 31, 32. Face 31 has two oblong holes 33, 34 formed side by side and extending vertically, whose dimensions are adapted for receiving respectively post 13 and the collar 19a of post 19 of case a finger 35 extending horizontally in the plane of face 31 from its edge opposite the other face 32, a lower notch 36 adjacent the bend of the reciprocating assembly 30 and an upper notch 37. ,Face 31 of the reciprocating assembly 30 further comprises a perpendicular finger 38 disposed above and in line with the oblong hole 33.
A projection 41 carried by face 31 forms, with face 32, a fork receiving a horizontal shaft 42 parallel to face 31. A mobile wedge 45 and a helical spring 43 are mounted side by side on shaft 42 (figures 1a and 5). Spring 43 bears by one end on face 31 and by the other end on a laterally projecting shoulder 46 provided on the mobile wedge 45.
The mobile wedge 45 has a recess 47 opening both into its upper face and its side face opposite shoulder 46, which is intended for cooperating with a stop pin 44 projecting perpendicularly from face 32. The mobile wedge 45 is therefore returned resiliently to a horizontal position in which it abuts the stop pin 44, but it may be pushed downwards so as to pivot in a clockwise direction (FIG. 5) through a certain angle at least.
The reciprocating assembly 30 is intended to be applied on the bottom 2 of case 1 by means of a spacer 39 in the form of a cylinder mounted on post 19 and whose outer diameter is greater than the oblong hole 34. Spacer 39 is fixed by screw 40 cooperating with a threaded portion of post 19. The reciprocating assembly 30 bears against the two studs 21, 22 of case 1 so that it can only make a vertical translational movement between a top position (FIG. 2a) and a bottom position (3a) in each of which one end of the oblong holes 33, 34 abuts respectively against post 13 and against the collar 19a of post 19.
A rocker arm 50 in the form of an L disposed in a vertical plane has two holes 51, 52, a perpendicular finger 53 disposed at the lower part of the rocking lever 50 and a perpendicular projection 54. A pusher 55 has a thickened portion 56 at one end, a rounded portion 57 turned downwardly at the opposite end and a hole 58 in a central region. A pin 59 passes through hole 58 of pusher 55 and hole 51 of the rocking lever 50. The rocking lever 50 is mounted for rotation by its hole 52 on post 17 of case 1, between a straight position (FIG. 3a) and an inclined position (FIG. 2a). It is returned resiliently to the straight position by a helical spring 60 mounted on post 15 and one end of which bears on post 18 of the case and the other end on a sidewall of the rocking lever 50. Rotation of the rocking lever 50 in a clockwise direction is limited by stud 20 against which the upper part of the rocking lever abuts its rotation in an anti-clockwise direction is limited by the sidewall 3 of case 1. The pusher passes, with its rounded end 57, through aperture 7 in all the angular positions of the rocking lever 50. It may pivot with respect to the rocking lever 50 about the pin 59. Because of the presence of its thickened portion 56, the pusher 55 tends to rotate in a clockwise direction under the effect of gravity. Its rotation in an anti-clockwise direction is only limited by the upper part of sidewall 3 of the case, against which its thickened portion 56 will abut. Its rotation in a clockwise direction is limited either by projection 54 of the rocking lever 50 against which it abuts when the rocking lever is in the vertical position (FIG. 3a), or by the upper edge of the aperture 7 against which it abuts when the rocking lever 50 is in the inclined position (FIG. 2a).
A bolt 70 with the general shape of an L on its side comprises a front parallelepipedic end 71 intended to pass through the aperture 8 in case 1 for cooperating with a bar operating device described subsequently. It has a stop face in the extended position 72 and a stop face in the retracted position 73 which are vertical and turned towards the parellelepipedic end 71 and a slanted stop face 74 turned towards its rear end which is intended to cooperate with the finger 38 of the reciprocating assembly 30.
On its main face turned outwardly of case 1, bolt 70 has two studs 75, 76 adjacent the front end 71 and a stud 77 adjacent the rear end. On its main face opposite thereto, it has a rear stud 78 disposed lower and more to the rear than stud 77 (FIG. 2b), and a vertical shoulder 79 which means that the rear part of bolt 71 is thinner than its front part (FIGS. 8 and 9).
A scrambling finger 80 has a hole 82 by which it is mounted for pivoting on stud 78 of bolt 70 by being rotated towards the front end 71 of the bolt. On its main face turned towards the bottom of case 1 and in its upper part, the scrambling finger 80 comprises a projecting shoulder 81 extending horizontally.
A traction hook 90 has at one end a hole 93 and, at the opposite end, and on its main face turned towards the bottom of case 1, a projecting shoulder 91 extending along a curved line, as shown in FIGS. 4b and 9. This hook is mounted for pivoting on stud 76 of bolt 70, so as to be turned rearwardly of the bolt and with interpositioning of a spacing washer 92 whose thickness corresponds to that of shoulder 91 of the traction hook 90.
A disengagement finger 94 has a hole 95 by which it is mounted for pivoting on stud 77 of bolt 70. A spacing washer 96 is also mounted on stud 77 so as to cap the disengagement finger 94.
A blade spring 85 having a general V shape has two branches, one of which is deformed so as to form a gripper 86 for surrounding post 14 of case 1.
A spacing washer 97 has a re-entrant shoulder at both ends, one being received in hole 11 at the bottom of case 1 and the other receiving a helical spring 98.
Bolt 70, equipped with the scrambling finger 80, with the traction hook 90 and the disengagement finger 94 is disposed in case 1, in front of the reciprocating assembly 30 and the rocking lever 50. These parts are shown in FIG. 8, where it can be seen that the shoulder 79 of bolt 70 advantageously allows the scrambling finger 80 to be partiallY housed.
Bolt 70 may be moved in a straight line in case 1 between an extended position (FIG. 2b) and a retracted position (FIG. 3b). In these two positions, its front end 71 bears on the lower edge of the aperture 8 of case 1. Furthermore, the blade spring 85 bears by one of its branches on the sidewall 4 of the case and by the other on stud 75 of bolt 70, so that the bolt 70 is returned resiliently to its extended position. As will be mentioned hereafter, the rear part of the bolt is supported by an aperture 191 in a plate 190 covering the lock. In addition, in the retracted position of bolt 70, the helical spring 98 bears by one of its ends on the sidewall 5 of the case and by the other end on the disengagement finger 94 and tends to cause this latter to pivot in a clockwise direction.
In the extended position, bolt 70 abuts with its stop face 72 against the sidewall 3 of the case. Before the combination of the lock has been formed for opening it (FIGS. 2a and 2b) and as mentioned hereafter, the reciprocating assembly 30 is in the top position and the mobile wedge 45 which it carries is then situated behind the rear end of bolt 70 : it follows that bolt 70 cannot be pushed manually towards its retracted position for it would abut against the mobile wedge 45. On the other hand, once the combination is formed, bolt 70 may be retracted at most until it abuts with its rear end against the spacer socket 97.
In a way known per se, the lock comprises several apertured combination disks 100 (figures 1b and 2a), which are open along a radial slit 101 and which have a notch 102 on their radial outer edge; in accordance with the invention, however, one of the ends 103 of the notch is connected to the outer edge of the disk along a radius intended to cooperate with finger 38 of the reciprocating assembly 30. In line with slit 101, each combination disk has a hole 104 for moving it away by means of a key. Apertured cores 110, whose outer diameter is a little greater than the inner diameter of the combination disks, may thus be mounted by resilience therein. Each core has on one face a finger 111 parallel to the axis of the core and on the other face an annular flange 112 itself carrying a finger 113 extending radially outwardly.
In a way also known per se, the lock comprises secondary apertured drive disks 120, having on their radially inner edge a notch 121 and, opposite thereto, a finger 122 extending parallel to the axis of the disks. Furthermore, a main drive disk 130 (FIGS. 1b and 3b) is provided whose structure is specific to the present invention. It is formed of two disks 140, 150 applied permanently one against the other and having different outer diameters, the smallest diameter disk 140 having a cut-out 141 opening outwardly and towards its radially outer edge, disk 150 having a similar cut-out 151 disposed in line with the cut-out 141, and whose bottom 152 extends peripherally along an arc of a circle of a radius equal to the radius of the other disk 140. The cut-out 151 extends over an angular portion greater than that along which cut-out 141 extends. Moreover, disk 140 has a circular central thickened portion 142 and disk 150 has a finger 153 parallel to its axis. Finally, the main drive disk 130 as a whole comprises a through hole 131 of square section.
An apertured spacer disk 160 has, seen in a top view, an external shape and size identical to those of disk 150, so in particular cut-out 161. It has in addition, an aperture 162 extending along a circle portion defined by an angular sector a little greater than that along which the cut-out 151 in disk 150 extends.
Spacer plates 170, known per se, are interposed between the combination disks 100 and the secondary drive disks 120 on the one hand ,and between the spacer disk 160 and the secondary adjacent drive disk 120. Some have bosses 171 distributed peripherally for bearing on the adjacent spacer plate or on the spacer disk 160. Each spacer plate has two lower holes 172 through which pass the posts 15, 16 of case 1 and a mid-height hole 173 disposed opposite the hole 104 in the combination disks 100.
The combination disks 100, cores 110, the main 130 and secondary 120 drive disks and the spacer plates 170 are fitted on the post 13 of case 1, with previous interpositioning of a washer 180. A cover plate 190 holds all the parts of the lock applied against each other in case 1. It is held in position by screwing on to the three posts 14 to 16 of the case. It has a horizontal aperture 191 in its right hand upper part which is intended to guide and support stud 77 of bolt 70 during the translational movement thereof.
The lock as a whole is fixed to a door panel 200 by means of threaded posts 201 secured to this panel, one of them passing through the spacer socket 97, these posts cooperating with nuts 202. A control knob 210 for the lock comprises a cylindrical surface 211 graduated circumferentially and a square section rod 212 passing through the door panel 200 for cooperating with the square hole 131 in the main drive disk 130. A cylindrical housing 220 is adapted for receiving and masking the graduated portion 211 of the control knob 210. It has a notch 221 in its upper part allowing the graduated surface 211 to be observed solely by the user of the lock and positioning of the knob 210 opposite a mark 222. Housing 220 is fixed by appropriate means to the door panel 200 and the knob 210 is coupled to housing 220 by appropriate means -so as to only allow rotation of the knob with respect to the housing.
In operation, when knob 210 is rotated in a clockwise direction, it drives the main drive disk 130. At a given moment during such rotation, finger 153 of the main drive disk 130 abuts against one end 163 of the aperture 162 of the spacer disk 160 and then rotates this latter. The arrangement is such that the notches 151 and 161 in the respective disks 130, 160 then occupy the same angular position.
On the other hand, when the main drive disk 130 is rotated in an anti-clockwise direction, its finger 153 abuts against the other end 164 of aperture 162 of the spacer disk 160 and then rotates this latter (FIG. 2b). The arrangement is such that notches 151 and 161 of respective disks 130, 160 are then offset angularly, so that notch 151 is masked by the spacer disk 160.
Furthermore, and in a way known per se, finger 153 of the main drive disk 130 abuts against the finger 122 of the secondary drive disk 120 which begins to rotate. When notch 121 of this disk abuts, by one end, against the radial finger 113 of the adjacent core 110, this latter rotates in its turn. Similarly, the axial finger 111 of core 110 drives the adjacent secondary drive disk 120, which drives the adjacent core 110. Since the combination disks 100 are fast with the cores 110, they rotate so that the angular position of their notch 102 is modified. Also in a way known per se, for opening the lock, it is necessary first of all to position the bottom-most combination disk 100 in the case so that its notch 102 is in the top position (FIGS. 3a and 4a), for example by rotating the knob 210 in a clockwise direction. Then the second combination finger 100 is positioned by rotating the knob in an anti-clockwise direction.
As is clear from FIG. 10, and in this embodiment, a mechanism for closing the door is mounted on the panel of the door, beside the case 1 of the lock. In a way known per se, this mechanism comprises a keeper 230 extending substantially in the plane of the lock, which has one L shaped end 231 with a rectangular opening 232 for receiving the end 71 of the bolt 70, and another end, also with a rectangular opening 233. This keeper is mounted for pivoting in its plane on a shaft 234.
Above and below shaft 234 two bars 240, 250 are mounted for pivoting by one end about two shafts 241, 251 and extend respectively upwards and downwards and are intended to cooperate with keepers provided in a casing of the door. A vertical bracket 260 in the form of an L has on one leg a pin 261 adapted for moving in the opening 233 of keeper 230 and on another leg two horizontal bolts 262, 263 disposed one below the other and adapted for cooperating with two corresponding keepers provided on the casing of the door.
A handle 270 is used for rotating keeper 230. In a way also known per se, rotation of handle 270 in the direction of arrow 271 (FIG. 10) allows the bars 240, 250 and bolts 262, 263 to be driven in the direction of arrows 272 so as to move them away from the keepers with which they cooperate, and rotation of the handle in the opposite direction results in causing them to penetrate into the keepers.
According to the invention, the L shaped end 231 of keeper 230 has a perpendicular screw 235 projecting outwardly which is immobilized by a nut 236.
The operation of the lock as a whole will now be described. It will be considered that the lock is closed (FIGS. 2a, 2b). Bolt 70 is in the extended position, in which it penetrates into opening 232 in keeper 230. The disengagement finger 94 hangs under the effect of its own weight, for spring 98 does not cooperate with it. The relative position of the drive disk 130 and of the spacer disk 160 then depends on the direction of rotation in which knob 210 was last rotated. Such as shown in FIG. 2b, it has been considered that the knob has been rotated in an anti-clockwise direction, so that the two disks 130, 160 are offset angularly and the finger .38 of the reciprocating assembly 30 may then either bear on both of them, as shown in FIG. 2b, or bear on disk 160 alone if the knob is rotated through about 180° in an anti-clockwise direction and if notch 151 faces the finger 38 of the reciprocating assembly 30. In both cases, finger 38 is supported at the same height so as to be situated a little above the combination disks 100 (FIG. 2a). With this arrangement, it is not possible to attempt to discover the coded combination of the lock by rotating knob 210: in known locks, where finger 38 rested on the combination disks, it was possible to hear the impact of finger 38 rubbing against one or other of the notches 102 of these disks.
The reciprocating assembly is therefore in the top position so that the mobile wedge 45 is situated behind the bolt 70, preventing this latter from being pushed inwardly of the lock. The scrambling finger 80 rests by its shoulder 81 on the face 31 of the reciprocating assembly 30. The combination disks 100 are in a random angular position.
The traction hook 90 rests by its shoulder 91 on finger 38 of the reciprocating assembly 30 and is therefore held in a top position not allowing it to penetrate into the notch 141 in the drive disk 130.
Finally, the rocking lever 50 bears by its finger 53 under bolt 70 (FIG. 2a) and is therefore held in a slanted position so that pusher 55 is almost completely retracted into the lock and is not in contact with the screw 235 carried by the keeper 230.
We will now consider that the coded combination has been made by rotating knob 210 (FIGS. 4a and 4b) in one direction and in the other alternately, and for the last time in an anti-clockwise direction. Notches 102 of the two combination disks 100 are therefore aligned in the top position. Knob 210 was then rotated in a clockwise direction so that notch 151 is progressively no longer masked by the spacer disk 160, and so that the finger 38 on the reciprocating assembly 30 falls on the bottom 152 of notch 151 whose radial distance is identical to that of the bottom of notches 102 in the combination disks 100 in FIG. 4a, finger 38 is therefore at the bottom of notches 102.
Consequently, the traction hook 90 has pivoted under the effect of gravity until it abuts against the bottom of notch 141 of the main drive disk 130 : it will in fact be noted that, in FIG. 4b, the traction hook 90 is no longer supported by the finger 38 of the reciprocating assembly 30.
Another consequence is that the reciprocating assembly 30 has moved to its low position. The scrambling finger 80 is therefore no longer supported by the reciprocating assembly 30 and bears on the combination disks 100. Furthermore, the mobile wedge 45 has moved to its low position in which it no longer prevents retraction of bolt 70.
Such as shown in FIGS. 4a, 4b, the lock is ready to be opened. It is sufficient to continue rotating knob 210 in a clockwise direction so as to drive the traction hook 90 towards the right and so cause retraction of bolt 70. The progressive retraction of bolt 70 has three successive effects : firstly the scrambling finger 80 moves back, its free end sliding over the combination disks 100 until it falls into the notch 102 thereof secondly, finger 53 of the rocking lever 50 "falls" in the shoulder of bolt 70 defined by the stop face 73 since this finger rubs against the bolt while being resiliently urged to rotate anti-clockwise finally, since the traction hook moves rightwards (FIG. 4b), it pushes the disengagement finger 94 against the effect of spring 98.
At the moment when the user releases knob 210, spring 98 causes the disengagement finger 94 to pivot in a clockwise direction, the disengagement finger itself causing the traction hook 90 to pivot in an anti-clockwise direction so that this latter leaves the notch 141 of the main drive disk 130 and comes against the sidewall 4 of the lock case 1.
The situation then obtained is illustrated in FIGS. 3a, 3b. The bolt is held in the retracted position by the finger 53 of the rocking lever 50. It will be noted that knob 210 can then only be rotated through an angular portion corresponding to that over which notch 151 of the main drive disk extends. In fact, in one direction as in the other, the edges of notch 151 tend to raise finger 38 now, this latter cannot be raised for it abuts against the slanting stop face 74 of bolt 70. This prevents an attempt by the user to lift finger 38 so as to lift the scrambling finger 80 and avoid scrambling of the combination disks 100.
Once the lock is opened, the keeper 230 may be rotated in a clockwise direction (FIGS. 3a, 3b) from a horizontal position (FIG. 10) by means of the handle 270. In fact, the bolt 70 no longer passes through opening 232 in keeper 230 and the screw 235 of the keeper abuts, during rotation, against pusher 55 which retracts while pivoting in an anti-clockwise direction. The door is then open.
To close the door again, handle 270 is rotated and so is keeper 230 in an anticlockwise direction. Screw 235 comes into abutment against the rounded end 57 of pusher 55. Now, this latter cannot pivot in a clockwise direction since it bears against the projection 54 of the rocking lever 50, so that the rocking lever is pushed in a clockwise direction against the effect of spring 60. The result is that the finger 53 of the rocking lever 50 is released from the stop face 73 of bolt 70 : the bolt is then pushed instananeously towards its extended position by the blade spring 85.
During extension of bolt 70, the scrambling finger 80 is driven leftwards in FIG. 3a, so that it pushes the combination disks 100 which rotate randomly through a certain angle. In practice, it has been observed that the different combination disks did not exactly cover the same path, so that their notches 102 are no longer aligned.
Since the combination disks 100 are rotated anti-clockwise, through the rounded end 103 of the notch 102 they push the finger 38 of the reciprocating assembly 30 back to its top position. Furthermore, with the traction hook 90 moving away from the disengagement finger 94, it is no longer supported thereby and comes into abutment against finger 38 of the reciprocating assembly 30.
The situation then obtained is the initial situation illustrated in FIGS. 2a, 2b.
In this embodiment, it has been ascertained that extension of bolt 70 takes place more slowly than rising of the reciprocating assembly 30. That means that the mobile wedge 45 abuts against the rear part of bolt 70 during rising of the reciprocating assembly 30. But since this wedge is mounted for pivoting, the mechanism of the lock is not locked, the mobile wedge 45 being pushed back downwards through a certain angle.
It will be noted that, in the absence of the disengagement finger 94, the traction hook 90 would remain in the notch 141 of the drive disk 130 after the lock has been opened, which would allow the user, by immobilizing knob 210, to prevent the automatic extension of bolt 70 when closing the door. The result would be that the lock would not be closed and the combination disks 100 would not be scrambled. In fact, it is therefore preferable to provide a disengagement finger 94.
In a way known per se, modification of a coded combination of the lock is achieved by introducing through the rear of the lock a key or rod passing through the hole 12 in case 1, holes 104 in the combination disks 100 and holes 173 in the spacer plates 170. The combination disks are then moved aside and their cores 110 may be rotated by operating knob 210. Finger 35 of the reciprocating assembly 30 advantageously rests on the key during this operation since it is situated in line with hole 12 in case 1 (FIG. 2a) : the reciprocating assembly 30 is therefore held in the top position, so that the traction hook 90 is moved away from the drive disk 130 which may rotate freely.
In another embodiment of the invention, no door closure mechanism is provided at the side of the lock so that the bolt of the lock cooperates directly with the fixed keeper of a door casing, the knob serving as handle for opening the door. In this case, the means for unlocking the bolt in the retracted position, for example a pusher, are adapted for cooperating with the fixed keeper.
The above described lock operates satisfactorily. However, it may be discovered that after opening the lock, the traction hook 90 can only be withdrawn from the main drive disk 130 if the user has previously released knob 210. FIG. 11, showing a lock modification including all the elements of the first lock, and in which the unchanged elements bear the same references as in the first lock, illustrates the state of the lock after opening but before the user has released knob 210 (figure 1b).
In this situation, the traction hook 90 is held prisoner in notch 1410 of the main drive disk 1300. Thus, although the disengagement finger 94 bears on the traction hook 90, it cannot cause it to pivot in an anti-clockwise direction. This is what allows the user to prevent the automatic extension of bolt 70 during closure of the door and thus prevent closure of the lock and scrambling of the combination disks.
The lock shown in FIGS. 11 and 12 is adapted for forcing the user to release the knob 210 before the door can be opened. The main drive disk 1300 comprises, like that 130 of the preceding lock, two disks applied side by side 1400, 1500 and it differs therefrom in that its disk 1400 comprises a second V shaped notch 1420, defined by two faces 1421, 1422. An auxiliary bolt 700 is provided in the form of a T comprising a leg 701 and two arms 702, 703, one cf which 703 is extended by a finger 704 of smaller width, rounded at its end.
The auxiliary bolt 700 is mounted in the lock, against the face of bolt 70 turned outwardlY of the lock. Its arm 702 passes through an aperture 800 formed in case 1000, below aperture 8. Its arm 703 is guided between the base of the traction hook 90 and post 15. Its leg 701, turned towards the sidewall of case 1000 extends between the sidewall 3 and the base of the traction hook 90. Thus, the auxiliary bolt 700 may slide in a direction parallel to the sliding direction of bolt 70.
A helical spring 1600 is mounted on post 14 and comprises two legs 1601, 1602 one of which bears on the sidewall 4 of case 1000 and the other on a side face of leg 701 of the auxiliary bolt 700, turned towards the sidewall 3 of case 1000, so that the auxiliary bolt is urged to a retracted position. Thus, finger 704 of the auxiliary bolt bears against the side face of disk 1400. In the situation shown in FIG. 11 where the user has not released knob 210 (figure 1b), finger 704 bears on the unnotched portion of the side surface of disk 1400, so that arm 702 of the auxiliary bolt 700 extends outwardly of case 1000 beyond bolt 70, until it passes through an aperture 2321 formed in keeper 2300, below aperture 2320 intended to receive the bolt 70. Under these conditions, the user cannot open the door.
On the contrary, in FIG. 12, the user has released knob 210 so that the traction hook 90 has come out of notch 1410 : the lock is in a condition similar to that shown in FIG. 3b. It is now notch 1420 of disk 1400 which faces the finger 704 of the auxiliary bolt 700. The auxiliary bolt 700 thus released allows it to slide to a retracted position in which it bears against face 1422 of notch 1420 and where it no longer cooperates with keeper 2300 : the user can then open the door. | A lock comprising notched combination disks, a bolt movable in translation and urged to its extended position which may be moved solely when a coded combination has been formed by rotation of the combination disks, and means for driving the bolt to its retracted position. In accordance with the invention, the lock comprises means for locking the bolt in the retracted position, means for making said bolt drive means inoperative when the bolt is in its retracted position, and means for unlocking the bolt once the door has been opened then closed again. | 4 |
[0001] This application is based on Japanese Patent Application Nos. 2004-269868 and 2004-269881 filed on Sep. 16, 2004 in Japanese Patent Office, the entire content of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a recording medium conveying device, particularly to a recording medium conveying device which conveys a recording medium in accordance with image recording.
[0003] An image recording apparatus such as an ink jet printer is equipped with a recording medium conveying device which conveys a recording medium in accordance with image recording (see the Patent Documents 1 and 2, for examples.) The recording medium conveying device has a master roll holding section that holds the master roll of the recording medium upstream of the platen which is positioned in an image recording area of the image recording apparatus, and it also has an ejecting section that ejects the recording medium after recording an image downstream of the platen.
[0004] If the recording medium is lifted in this operation, the distance between the recording head and the recording medium becomes non-uniform, resulting in image quality degradation. Accordingly, the recording medium conveying device conveys the recording medium along the platen so as to maintain flatness.
[0005] [Patent Document 1] Tokkai No. 2000-326572
[0006] [Patent Document 2] Tokkai No. 2003-137464
[0007] However, an ink jet printer may record images on various different kinds of recording media and, because the stiffness of a recording medium is different from type to type, the recording medium may be lifted on the platen depending on its stiffness.
[0008] For example, a recording medium with high stiffness can be conveyed smoothly without being in tension because of its high stiffness, but a recording medium with low stiffness cannot be conveyed at a stable feed rate if no tension is added to the medium. Accordingly, if the conveyance path is so designed that the recording medium is tilted upward in the traveling direction when it enters the platen, tension is added by the weight of the recording medium itself. However, if a recording medium with high stiffness is conveyed on this conveyance path, there is a possibility that the recording medium is lifted from the platen because of its stiffness when it transfers from the tilted portion onto the platen. On the other hand, when the recording medium is ejected after having an image recorded, a recording medium with high stiffness can be ejected smoothly without added tension because of its high stiffness. In case of ejecting a recording medium with low stiffness, however, if no tension is added, buckling may be caused by the conveyance resistance to the recording medium when it is separated from the platen. This buckling may cause the recording medium to rub against the discharge surface of the recording head, possibly resulting in recording medium jamming.
[0009] If the conveyance path is so designed that the recording medium is tilted downward in the traveling direction when the recording medium separates from the platen, tension is added by the weight of the recording medium itself. However, if a recording medium with high stiffness is conveyed on this conveyance path, the recording medium may be lifted from the platen because of its form maintaining force due to the stiffness when the recording medium hangs down, and may rub against the discharge surface of the recording head, possibly resulting in recording medium jamming.
SUMMARY OF THE INVENTION
[0010] An object of the present invention is to ensure conveyance accuracy and smooth ejection of recording medium having different stiffness.
[0011] A recording medium conveying device comprising: a master roll holder to hold a master roll of a recording medium; a platen to support the recording medium supplied from the master roll holder in an image recording section; a conveyance roller positioned upstream of the platen to convey the recording medium by providing driving force to the recording medium and a guide positioned near the platen to guide the recording medium, wherein the guide changes the angle of the recording medium against the platen according to the stiffness of the recording medium.
[0012] A recording medium conveying device as set forth in an embodiment of the invention (the first embodiment) comprises; a master roll holding section that holds a master roll of the recording medium, a conveyance roller located upstream of the platen of the image recording apparatus, that adds a driving force to the recording medium and conveys it, an entrance section that guides the recording medium from the master roll holding section to the conveyance roller; and the entry angle with the platen in the entrance section at which the recording medium enters the conveyance roller, is freely changeable corresponding to the stiffness of the recording medium.
[0013] According to an embodiment of the invention, since the entry angle is changed in the entrance section corresponding to the stiffness of the recording medium, the entry angle suitable for each kind of recording medium can be set. Accordingly, the entry angle can be so changed as to add tension for a recording medium with low stiffness, and the entry angle can be so changed as to prevent lifting from the platen and maintain flatness of a recording medium with high stiffness. Thus, even for recording media with different stiffness, conveyance accuracy can be ensured.
[0014] A recording medium conveying device as set forth in another embodiment of the invention (the second embodiment) comprises; a master roll holding section that holds a master roll of the recording medium, a conveyance roller located downstream of the master roll holding section that adds a driving force to the recording medium and conveys it to the platen of the image recording apparatus, an ejection section that ejects the recording medium after recording downstream of the platen, and the tilt angle of the recording medium in the ejection section is freely changeable corresponding to the stiffness of the recording medium.
[0015] According to an embodiment of the invention, since the tilt angle is changed in the ejection section corresponding to the stiffness of the recording medium, a tilt angle suitable for each recording medium can be set. Accordingly, the tilt angle can be so changed as to add tension to a recording medium with low stiffness, and the tilt angle can be so changed as to prevent lifting from the platen and to maintain flatness of the recording medium with high stiffness. Thus, even for a recording medium with different stiffness, smooth ejection can be ensured.
[0016] According to the present invention, since the entry angle or tilt angle can be so changed that tension is added to a recording medium with low stiffness, and since the entry angle or tilt angle can be so changed that lifting from the platen is prevented and flatness is maintained of a recording medium with high stiffness, conveyance accuracy and smooth ejection can be ensured for recording media with different stiffness.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic structural view of an image recording apparatus equipped with a recording medium conveying device according to this embodiment.
[0018] FIG. 2 explains the stiffness of the recording medium conveyed on the recording medium conveying device in FIG. 1 .
[0019] FIG. 3 is a block diagram showing the structure of the major control of the first embodiment of the image recording apparatus 1 in FIG. 1 .
[0020] FIG. 4 is a block diagram showing the structure of the major control of the second embodiment of the image recording apparatus 1 in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] Further preferred embodiments of the invention to solve the above problems will now be explained.
[0022] In the recording medium conveying device of the invention, the guide is structured so that the entry angle or tilt angle can be so changed that the recording medium becomes parallel to the platen for a recording medium with high stiffness, and that the recording medium with low stiffness becomes perpendicular to the platen.
[0023] When the recording medium with high stiffness is conveyed, according to the embodiment of the invention, the entry angle and/or tilt angle are/is so changed that the recording medium becomes parallel to the platen, which means that a conveyance path and/or ejection path without a tilt are/is formed in immediately upstream and/or downstream of the platen. When there is no tilt in the path like the above, lifting of a recording medium with high stiffness from the platen can be prevented.
[0024] On the other hand, when a sheet of recording medium with low stiffness is conveyed, the entry angle is so changed that the recording medium becomes perpendicular to the platen, which means that tension is added to the recording medium upstream of the conveyance roller by its own weight. When tension is added to the recording medium with low stiffness like the above, feed rate can be kept stable. In the ejection path, on the other hand, when a sheet of recording medium with low stiffness is conveyed, the tilt angle is so changed that the recording medium becomes perpendicular to the platen, which means that tension is added to the recording medium downstream of the platen by its own weight. When tension is added to the recording medium with low stiffness like the above, smooth ejection is ensured without buckling.
[0025] In the recording medium conveying device of the first embodiment, multiple master roll holding sections are installed vertically, and the upper master roll holding section holds a master roll of recording medium with higher stiffness than the recording medium held in a lower master roll holding section.
[0026] Generally speaking, since sheets of recording medium with low stiffness are more frequently used than sheets of recording medium with high stiffness, it requires frequent master roll changes, as a matter of course. In addition, since a master roll of recording medium is very heavy, changing the roll becomes difficult if the master roll holding section is located high in the apparatus. If the recording medium with stiffness higher than that of recording medium held in the lower holding section is held in the upper master roll holding section, which means that if the recording medium roll with low stiffness requiring more frequent changes is located lower, operator burden of the change work can be reduced.
[0027] The recording medium conveying device in the second embodiment has a winding section positioned below the ejection section to wind recording medium when the tilt angle is changed to vertical.
[0028] According to the embodiment, since the winding section winds the recording medium under the ejection section, a recording medium with low stiffness can be wound after tension is provided. Generally, a recording medium with low stiffness is more frequently used and becomes easier to handle in a state after being wound like this.
[0029] The recording medium conveying device of the invention is provided with a control section that controls the entrance section and/or the ejection section so that the entry angle and/or tilt angle correspond(s) to the stiffness of the recording medium.
[0030] According to the invention, since the control section controls the entrance section so that the entry angle corresponds to the stiffness of the recording medium, automatic entry angle changes become possible. On the other hand, since control section controls the ejection section so that the tilt angle corresponds to the stiffness of the recording medium, automatic tilt angle change in the ejection path becomes possible.
[0031] Next, the first embodiment and the second embodiment will be explained in detail.
The First Embodiment
[0032] The first embodiment is the recording medium conveying device equipped with an entrance section in which the entry angle with the platen, at which the recording medium enters the conveyance roller, is freely changeable corresponding to the stiffness of the recording medium, which is described hereunder.
[0033] The recording medium conveying device of the present invention is described hereunder, using the attached figures.
[0034] FIG. 1 is the image recording apparatus 1 equipped with the recording medium conveying device of this embodiment. As shown in FIG. 1 , the image recording apparatus 1 is equipped with a case 3 that encloses the recording medium conveying device 2 , platen 4 that is supported above the case 3 and supports the recording medium P or Q horizontally from beneath, and recording head 5 that is located above the platen 4 and emits ink onto the recording medium P or Q supported by the platen 4 .
[0035] The recording medium conveying device 2 has two master roll holding sections 21 and 22 , located vertically, each of that holds each master roll P 1 and Q 1 of the recording media P and Q. Among the two master roll holding sections 21 and 22 , the upper master roll holding section 21 holds the master roll P 1 of the recording medium P having higher stiffness than the recording medium Q held in the lower master roll holding section 22 .
[0036] In the meantime, stiffness of recording medium is explained here. “Stiffness” is generally understood as one of the indexes for evaluating the strength as to how an article will not bend against a bending force, and its quantitativeness is in a range of comparative relativity. The quantitative value of the stiffness is measured for example by a method shown in FIG. 2 . Different types of recording media R of the same size (A4, for example) are prepared. Each type of the recording media is placed on a level table 100 . In this procedure, the recording medium R shall be placed on the table 100 so that approximately a half length of the recording medium R projects out of the table 100 . The portion projecting out of the table 100 hangs down by its own weight. Provided that the horizontal distance from the tip of this hanging recording medium to the table 100 is X and the vertical distance from the tip to the upper surface of the table 100 is Y, the quantitative value is expressed as Y/X. For example, in case of a recording medium having little stiffness such as tarpaulin, X becomes smaller and so the quantitative value approximates to ∞; in case of a recording medium having high stiffness such as coated paper, Y becomes smaller and so the quantitative value approximates to 0.
[0037] The degree of stiffness of the recording media P and Q are judged by this measurement method, and the master roll P 1 of the recording medium P having high stiffness is held in the upper master roll holding section 21 and the master roll Q 1 of the recording medium Q having low stiffness is held in the lower master roll holding section 22 as shown in FIG. 1 .
[0038] The lower master roll holding section 22 is equipped with an unwinding section 23 that unwinds the master roll Q 1 in accordance with the feed rate of the recording medium Q, dancer roller 24 that is moved up and down by the unwound recording medium Q, and guide roller 25 that guides the recording medium Q from the master roll Q 1 to the dancer roller 24 . This master roll holding section 22 is constructed as a separate unit, and so it can be removed freely from the case of the image recording apparatus 1 .
[0039] The upper master roll holding section 21 is equipped with an oil damper 26 that adds load torque to the master roll P 1 of the recording medium P.
[0040] Then, the recording medium conveying device 2 is equipped with a conveyance roller 6 upstream of the platen 4 that adds drive force to the recording medium P or Q to convey them. In the upstream position of the conveyance roller 6 , there is provided an entrance section 7 that guides the recording medium P or Q from the master roll holding section 21 or 22 to the conveyance roller 6 .
[0041] The entrance section 7 is equipped with an entry angle changing member 71 as the guide of the entrance that supports the recording medium P or Q from below and also changes the entry angle against the conveyance roller 6 . The entry angle changing member 71 swings around its one end on the conveyance roller 6 side as a swinging axis. In addition, the corners of the other end of the entry angle changing member 71 are made arc-shaped.
[0042] The entrance section 7 is also equipped with an adjusting member 72 that is located under the conveyance roller 6 and adjusts the tilt angle of the entry angle changing member 71 . The tip of the adjusting member 72 is connected with the other end of the entry angle changing member 71 . On the other hand, the base end of the adjusting member 72 rotates as it travels horizontally. When the base end of the adjusting member 72 travels horizontally, the entry angle changing member 71 is swung because the tip of the adjusting member 72 is connected with the other end of the entry angle adjusting member 71 . In this embodiment, the base end of the adjusting member 72 is designed to stop at three points within its traveling range so that the entry angle can be changed at three steps by the entry angle changing member 71 .
[0043] In the above description, the entry angle means an angle of the recording medium P or Q with the flat surface of the platen 4 , that is, the horizontal surface at which the recording medium enters the conveyance roller 6 . The entry angle α 1 at the first step is set at 0 up to 45 degrees excluding 45 degrees, the entry angle α 2 at the second step is set at 45 up to 76 degrees excluding 76 degrees, and the entry angle α 3 at the third step is set at 76 to 90 degrees. In FIG. 1 , the entry angle changing member 71 and adjusting member 72 shown in solid line represent the third step setting at the entry angle α 3 , the entry angle changing member 71 a and adjusting member 72 a shown in alternate long and short dash line represent the second step setting at the entry angle α 2 , and the entry angle changing member 71 b and adjusting member 72 b shown in alternate long and short dash line represent the first step setting at the entry angle α 1 . Since the entry angle α 1 at the first step is set to 0 degree in this embodiment, the entry angle α 1 is not shown in FIG. 1 . These entry angles can be changed corresponding to the stiffness of the recording media P and Q. The entry angle α 1 at the first step is employed for the recording medium the quantitative value of which mentioned above (Y/X) is more than 0 but less than 1 (for example, coated paper, glossy paper, polycarbonate, etc.); the entry angle α 2 at the second step is employed for the recording medium the quantitative value of which is more than 1 but less than 4 (for example, supported glossy vinyl chloride, PET, Yupo synthetic paper, etc.); and the entry angle α 3 at the third step is employed for the recording medium the quantitative value of which is more than 4 (for example, tarpaulin, vinyl chloride sheet, etc.).
[0044] A recording medium the quantitative value of which is less than 1 is generally judged to have high stiffness. When a recording medium having high stiffness like this is conveyed, if the entry angle is so changed that the recording medium becomes parallel to the platen 4 , a conveyance path without a tilt is formed in immediately upstream of the platen 4 , which is preferable because lifting of the recording medium with high stiffness on the platen 4 can be prevented. That is, a preferable entry angle α 1 of the first step setting is 0 degree.
[0045] On the other hand, recording medium the quantitative value of which is more than 4 is generally judged to have low stiffness. When a recording medium having low stiffness like this is conveyed, if the entry angle is so changed that the recording medium becomes perpendicular to the platen 4 , it is preferable because tension is added to the recording medium upstream of the platen 4 by its own weight. That is, a preferable entry angle α 3 of the third step setting is 90 degrees.
[0046] Then, downstream of the platen 4 of the recording medium conveying device 2 , there is provided an ejection guide 81 that forms an ejection path of the recording media P and Q. The ejection guide 81 is constructed to swing around its one end on the platen 4 side as a swinging axis so that its position can be switched to the horizontal position (solid line in FIG. 1 ) or vertical position (alternate long and short dash line in FIG. 1 ). The ejection guide 81 is set to the horizontal position for ejecting the recording medium P with high stiffness and to the vertical position for ejecting the recording medium Q with low stiffness.
[0047] Under the ejection guide 81 , there is also provided a winding section 9 that winds up the recording section Q with low stiffness.
[0048] FIG. 3 is a block diagram showing the construction of the major control of the image recording apparatus 1 . As shown in FIG. 3 , the image recording apparatus 1 is equipped with a control section 10 that controls each drive source. The control section 10 is electrically connected with an adjusting member drive source 11 for moving the adjusting member 72 of the entrance section 7 horizontally, input section 12 to which an instruction of the operator is inputted, unwinding section 23 , recording head 5 , conveyance roller 6 , winding section 9 , and memory 13 . Other sections than the above such as drive sections of the image recording apparatus 1 are also connected with the control section 10 . The control section 10 controls each device and component in accordance with the control program and control data stored in the memory 13 .
[0049] Control data includes, for example, angle data that relate the afore-mentioned entry angles α 1 , α 2 and α 3 of each step with the types of the recording media P and Q.
[0050] Next, the operation of the recording medium conveying device 2 of this embodiment is described hereunder.
[0051] For conveying the recording medium P, the operator pulls out the recording medium P from the master roll P 1 held in the master roll holding section 21 as much as it can be conveyed by the conveyance roller 6 . In this procedure, the operator inputs the type of the recording medium P from the input section 12 . Upon this input, the control section 10 determines the entry angle based on the angle data in the memory 13 and the input data. When the first step entry angle α 1 is selected, for example, the control section 10 controls the adjusting member drive source 11 to move the adjusting member 72 up to a position where the tilt angle of the entry angle changing member 71 becomes the first step entry angle α 1 and stop it there. Here, the operator sets the ejection guide 81 to the horizontal position.
[0052] When the adjusting member 72 has stopped and the ejection guide 81 has been set, the operator instructs to start image recording from the input section 12 . Based on the input, the control section 10 controls the recording head 5 and conveyance roller 6 to emit ink onto the recording medium P to record images, while feeding the recording medium P intermittently. The recording medium P recorded with images is conveyed along the ejection guide 81 , keeping its horizontal position, and placed on a table (not shown).
[0053] On the other hand, for conveying the recording medium Q, the operator pulls out the recording medium Q from the master roll Q 1 held in the lower master roll holding section 22 via the guide roller 25 and dancer roller 24 as much as it can be conveyed by the conveyance roller 6 . In this procedure, the operator inputs the type of the recording medium Q from the input section 12 . Upon this input, the control section 10 determines the entry angle based on the angle data in the memory 13 and the input data. When the third step entry angle α 3 is selected, for example, the control section 10 controls the adjusting member drive source 11 to move the adjusting member 72 up to a position where the tilt angle of the entry angle changing member 71 becomes the third step entry angle α 3 and stops it there. Here, the operator sets the ejection guide 81 to the vertical position.
[0054] When the adjusting member 72 has stopped and the ejection guide 81 has been set, the operator instructs to start image recording from the input section 12 . Based on the input, the control section 10 controls the recording head 5 , conveyance roller 6 , unwinding section 23 and winding section 9 to emit ink onto the recording medium Q to record images, while feeding the recording medium Q intermittently. The recording medium Q recorded with images is conveyed along the ejection guide 81 , while hanging down vertically, and wound on the winding section 9 .
[0055] As described above, according to the recording medium conveying device 2 of this embodiment, the entry angle can be set suitable for different types of recording media P and Q because the entry angle is changed by the entrance section 7 corresponding to the stiffness of the recording media P and Q. Accordingly, the entry angle can be so changed that tension is added for the recording medium Q with low stiffness, and the entry angle can be so changed that lifting from the platen 4 is prevented and flatness is maintained for the recording medium P with high stiffness. Thus, conveyance accuracy can be ensured for the recording media P and Q with different stiffness.
[0056] In addition, since the control section 10 controls the entrance section 7 so that the entry angle becomes corresponding to the stiffness of the recording media P and Q, automatic entry angle change becomes possible.
The Second Embodiment
[0057] The second embodiment is the recording medium conveying device equipped with the ejection section in which the tilt angle in the ejection path is freely changeable corresponding to the stiffness of the recording medium, which is described hereunder.
[0058] Downstream of the platen 4 of the recording medium conveying device 2 , there is provided an ejection section 8 that forms an ejection path of the recording media P and Q. The ejection section 8 is equipped with an ejection guide 81 that supports the recording medium P or Q from below and forms the ejection path, and an ejection guide drive source 82 that swings the ejection guide 81 around its one end on the platen 4 side as a swinging axis (see FIG. 3 ).
[0059] The ejection guide 81 is swung by the ejection guide drive source so that its position can be switched to two positions: the horizontal position (sold line in FIG. 1 ) or vertical position (alternate long and short dash line in FIG. 1 ). Accordingly, the ejection section 8 changes the tilt angle in the ejection path of the recording media P and Q corresponding to the stiffness of the recording media P and Q.
[0060] In the above description, the tilt angle means an angle of the recording media P and Q with the flat surface of the platen 4 , that is, the horizontal surface at which the recording medium passes the ejection guide 81 . For example, the first tilt angle α 1 ′ when the ejection guide 81 is positioned flat is 0 degree. The second tilt angle α 2 ′ when it is positioned vertical is 90 degrees. This tilt angle can be changed corresponding to the stiffness of the recording media P and Q. The tilt angle α 1 ′ is employed for the recording medium the quantitative value of which mentioned above (Y/X) is more than or equal to 0 but less than 4 (for example, coated paper, glossy paper, polycarbonate, supported glossy vinyl chloride, PET, Yupo synthetic paper, etc.); and the tilt angle α 2 ′ is employed for the recording medium the quantitative value of which is more than 4 (for example, tarpaulin, vinyl chloride sheet, etc.).
[0061] It is preferable for smooth conveyance of the recording media P and Q that the surface of the ejection guide 81 is positioned lower than the surface of the platen 4 being arc-shaped with its swelling surface facing upward.
[0062] The winding section 9 is installed under the ejection section 8 to wind the recording medium Q when the tilt angle of the ejection path is changed to 90 degrees.
[0063] FIG. 4 is a block diagram showing the construction of the major control of the image recording apparatus 1 . As shown in FIG. 4 , the image recording apparatus 1 is equipped with a control section 10 that controls each drive source. The control section 10 is electrically connected with the input section 12 to which an instruction of the operator is inputted, unwinding section 23 , recording head 5 , conveyance roller 6 , winding section 9 , ejection guide drive source 82 , and memory 13 . Other sections than the above such as drive sections of the image recording apparatus 1 are also connected with the control section 10 . The control section 10 controls each device and component in accordance with the control program and control data stored in the memory 13 .
[0064] Control data includes, for example, angle data that relate the afore-mentioned first tilt angles α 1 ′ and second tilt angle α 2 ′ with the types of the recording medium.
[0065] Next, the operation of the recording medium conveying device 2 of this embodiment is described hereunder.
[0066] For conveying the recording medium P, the operator pulls out the recording medium P from the master roll P 1 held in the master roll holding section 21 as much as it can be conveyed by the conveyance roller 6 . In this procedure, the operator inputs the type of the recording medium P from the input section 12 . Upon this input, the control section 10 determines the tilt angle of the ejection path based on the angle data in the memory 13 and the input data. When the first tilt angle α 1 ′ is selected, for example, the control section 10 controls the ejection guide drive source 82 to swing the ejection guide 81 so that the ejection path is tilted at the first tilt angle α 1 ′ and stop it there. Thus, with the first tilt angle α 1 ′, the recording medium P is ejected through the ejection path where the recording medium P is parallel to the platen 4 .
[0067] Here, the operator moves the adjusting member 72 horizontally so that the tilt angle of the entry angle changing member 71 of the entrance section 7 becomes corresponding to the recording medium P.
[0068] When the adjusting member 72 has moved and the ejection section 8 has been set, the operator instructs to start image recording from the input section 12 . Based on the input, the control section 10 controls the recording head 5 and conveyance roller 6 to emit ink onto the recording medium P to record images, while feeding the recording medium P intermittently. The recording medium P recorded with images is conveyed along the ejection section 8 , keeping its horizontal position, and placed on a table (not shown).
[0069] On the other hand, for conveying the recording medium Q, the operator pulls out the recording medium Q from the master roll Q 1 held in the lower master roll holding section 22 via the guide roller 25 and dancer roller 24 as much as it can be conveyed by the conveyance roller 6 . In this procedure, the operator inputs the type of the recording medium Q from the input section 12 . Upon this input, the control section 10 determines the tilt angle of the ejection path based on the angle data in the memory 13 and the input data. When the second tilt angle α 2 ′ is selected, for example, the control section 10 controls the ejection guide drive source 82 to swing the ejection guide section 81 so that the ejection path is tilted at the second tilt angle α 2 ′ and stop it there. Thus, with the second tilt angle α 2 ′, the recording medium Q is ejected through the ejection path where the recording medium Q is perpendicular to the platen 4 .
[0070] Here, the operator moves the adjusting member 72 horizontally so that the tilt angle of the entry angle changing member 71 of the entrance section 7 becomes corresponding to the recording medium Q.
[0071] When the adjusting member 72 has moved and the ejection section 8 has been set, the operator instructs to start image recording from the input section 12 . Based on the input, the control section 10 controls the recording head 5 , conveyance roller 6 , unwinding section 23 and winding section 9 to emit ink onto the recording medium Q to record images, while feeding the recording medium Q intermittently. The recording medium Q recorded with images is conveyed along the ejection section 8 , while hanging down vertically, and wound on the winding section 9 .
[0072] As described above, according to the recording medium conveying device 2 of the second embodiment, the tilt angle can be set suitable for different types of recording media P and Q because the tilt angle is changed by the ejection section 8 corresponding to the stiffness of the recording media P and Q. Accordingly, the tilt angle can be so changed that tension is added for the recording medium Q with low stiffness, and the tilt angle can be so changed that lifting from the platen 4 is prevented and flatness is maintained for the recording medium P with high stiffness. Thus, smooth ejection can be ensured for the recording media P and Q with different stiffness.
[0073] In addition, when the recording medium P with high stiffness is conveyed, the tilt angle is so changed that the recording medium P becomes parallel to the platen 4 , which means that a conveyance path without a tilt is formed in immediately upstream of the platen 4 . When there is no tilt in the path like the above, lifting of the recording paper P with high stiffness from the platen 4 can be prevented.
[0074] On the other hand, when the recording medium Q with low stiffness is conveyed, the tilt angle is so changed that the recording medium Q becomes perpendicular to the platen 4 , which means that tension is added to the recording medium Q downstream of the platen 4 by the own weight. When tension is added to the recording medium Q with low stiffness like the above, generation of buckling can be prevented and accordingly smooth ejection can be ensured.
[0075] Since the winding section 9 located under the ejection section 8 winds up the recording medium Q with low stiffness, winding up the recording medium Q while adding tension to it becomes possible. Generally speaking, recording medium Q with low stiffness is used more frequently, but winding it up like the above facilitates easy handling.
[0076] In addition, since the control section 10 so controls the ejection section 8 that the tilt angle corresponds to the stiffness of the recording media P and Q, automatic tilt angle change of the ejection path becomes possible.
[0077] Needless to say, the present invention is not limited to the above embodiments but is modifiable as needed.
[0078] For example, although the recording medium conveying device 2 is equipped with two master roll holding sections 21 and 22 in the first embodiment, three or more master roll holding sections can be provided. Even in this case, it is preferable that a master roll of a recording medium with higher stiffness is held in an upper master roll holding section than a master roll holding section where a master roll of a recording medium with lower stiffness is held. In this construction, it is preferable that the master roll section in the lowest position is constructed as a separate unit and can be removed freely from the case like the master roll section 22 in this embodiment.
[0079] Further, in both the first embodiment and the second embodiment, guides the inclination angle of which is changeable are mounted on the entrance section and the ejection section, however they can be mounted on either the entrance section or the ejection section. The adjusting member drive source 11 for the entrance guide drive is connected to the control section 10 electrically in the first embodiment, and the ejection guide drive source 82 for the ejection guide drive is connected to the control section 10 electrically in the second embodiment. However, both the drive sources can be connected to the control section 10 .
[0080] In addition, although the entry angle is changed at three steps in the first embodiment, changing the entry angle to the most appropriate one for each type of the recording medium is possible if the relationship between the type of recording medium and the suitable entry angle for each type is kept as the angle data. In this data, the entry angle α n for each type is calculated as α n =a tan(Y/X) based on the quantitative value (Y/X) of each type.
[0081] In addition, although the tilt angle is changed at two steps in the second embodiment, changing the tilt angle to the most appropriate one for each type of the recording medium is possible if the relationship between the type of recording medium and the suitable tilt angle for each type is kept as the angle data. In this data, the tilt angle αn′ for each type is calculated as α n ′=a tan(Y/X) based on the quantitative value (Y/X) of each type. | A recording medium conveying device comprising: a master roll holder to hold a master roll of a recording medium; a platen to support the recording medium supplied from the master roll holder in an image recording section; a conveyance roller positioned upstream of the platen to convey the recording medium by adding driving force to the recording medium and a guide positioned near the platen to guide the recording medium, wherein the guide changes an angle of the recording medium against the platen according to a stiffness of the recording medium. | 1 |
[0001] This application claims the priority of U.S. provisional application No. 60/256,924, filed Dec. 21, 2000, the disclosure of which is expressly incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to electrodeposition process technology and, more particularly, to an electrodeposition process and apparatus that yield planar deposition layers.
[0004] 2. Description of Related Art
[0005] A conventional semiconductor device generally includes a semiconductor substrate, usually a silicon substrate, and a plurality of sequentially formed dielectric interlayers, such as silicon dioxide interlayers, and conductive paths or interconnects made of conductive materials. The interconnects are usually formed by filling a conductive material in trenches etched into the dielectric interlayers. In an integrated circuit, multiple levels of interconnect networks laterally extend with respect to the substrate surface. The interconnects formed in different layers can be electrically connected using vias or contacts. A conductive material filling process of filling such features, i.e. via openings, trenches, pads or contacts, can be carried out by depositing a conductive material over the substrate including such features. Excess conductive material on the substrate can then be removed using a planarization and polishing technique such as chemical mechanical polishing (CMP).
[0006] Copper (Cu) and Cu alloys have recently received considerable attention as interconnect materials because of their superior electromigration and low resistivity characteristics. The preferred method of Cu deposition is electrodeposition. During fabrication, copper is electroplated or electrodeposited on substrates that are previously coated with barrier and seed layers. Typical barrier materials generally include tungsten (W), tantalum (Ta), titanium (Ti), their alloys and their nitrides. A typical seed layer material for copper is usually a thin layer of copper that is CVD or PVD deposited on the aforementioned barrier layer.
[0007] There are many different Cu plating system designs. For example, U.S. Pat. No. 5,516,412, issued on May 14, 1996 to Andricacos et al., discloses a vertical paddle plating cell that is configured to electrodeposit a film on a flat article. U.S. Pat. No. 5,985,123, issued on Nov. 16, 1999 to Koon, discloses yet another vertical electroplating apparatus which purports to overcome the non-uniform deposition problems associated with varying substrate sizes.
[0008] During the Cu electrodeposition process, specially formulated plating solutions or electrolytes are used. These solutions or electrolytes contain ionic species of Cu and additives to control the texture, morphology, and plating behavior of the deposited material. Additives are needed to make the deposited layers smooth and somewhat shiny.
[0009] [0009]FIGS. 1 through 2 exemplify a conventional electrodeposition method and apparatus. FIG. 1A illustrates a substrate 10 having an insulator layer 12 formed thereon. Using conventional etching techniques, features such as a row of small vias 14 and a wide trench 16 are formed on the insulator layer 12 and on the exposed regions of the substrate 10 . Typically, the widths of the vias 14 are sub-micronic. The trench 16 shown in this example, on the other hand, is wide and has a small aspect ratio. The width of the trench 16 may be five to fifty times or more greater than its depth.
[0010] [0010]FIGS. 1B-1C illustrate a conventional method for filling the features with copper material. FIG. 1B illustrates that a barrier/glue or adhesion layer 18 and a seed layer 20 are sequentially deposited on the substrate 10 and the insulator 12 . After depositing the seed layer 20 , as shown in FIG. 1C, a conductive material layer 22 (e.g., a copper layer) is partially electrodeposited thereon from a suitable plating bath or bath formulation. During this step, an electrical contact is made to the copper seed layer 20 and/or the barrier layer 18 so that a cathodic (negative) voltage can be applied thereto with respect to an anode (not shown). Thereafter, the copper material layer 22 is electrodeposited over the substrate surface using plating solutions, as discussed above. By adjusting the amounts of the additives, such as chloride ions, a suppressor/inhibitor, and an accelerator, it is possible to obtain bottom-up copper film growth in the small features.
[0011] As shown in FIG. 1C, the copper material 22 completely fills the vias 14 and is generally conformal in the large trenches 16 , because the additives that are used are not operative in large features. Here, the Cu thickness t1 at the bottom surface of the trench 16 is about the same as the Cu thickness t2 over the insulator layer 12 . As can be expected, to completely fill the trench 16 with the Cu material, further plating is required. FIG. 1D illustrates the resulting structure after additional Cu plating. In this case, the Cu thickness t3 over the insulator layer 12 is relatively large and there is a step height s 1 from the top of the Cu layer on the insulator layer 12 to the top of the Cu layer 22 in the trench 16 . For IC applications, the Cu layer 22 needs to be subjected to CMP or other material removal processes so that the Cu layer 22 as well as the barrier layer 18 on the insulator layer 12 are removed, thereby leaving the Cu layer only within the features 14 and 16 . These removal processes are known to be quite costly.
[0012] Methods and apparatus to achieve a generally planar Cu deposit as illustrated in FIG. 1E would be invaluable in terms of process efficiency and cost. The Cu thickness t5 over the insulator layer 12 in this example is smaller than the traditional case as shown in FIG. 1D, and the step height s 2 is also much smaller than the step height s 1 . Removal of the thinner Cu layer in FIG. 1E by CMP or other methods would be easier, providing important cost savings.
[0013] In U.S. Pat. No. 6,176,992 B1 entitled “Method and Apparatus for Electrochemical Mechanical Deposition”, commonly owned by the assignee of the present invention, an electrochemical mechanical deposition (ECMD) technique is disclosed that achieves deposition of the conductive material into cavities on a substrate surface while minimizing deposition on the field regions by polishing the field regions with a pad as the conductive material is deposited, thus yielding planar copper deposits. The plating electrolyte in this application is supplied to the small gap between the pad and the substrate surface through a porous pad or through asperities in the pad.
[0014] Co-pending U.S. patent application Ser. No. 09/511,278, entitled “Pad Designs and Structures for a Versatile Materials Processing Apparatus” filed Feb. 23, 2000, now U.S. Pat. No. 6,413,388 B1, which is commonly owned by the assignee of the present invention, describes various shapes and forms of holes in pads through which electrolyte flows to a wafer surface.
[0015] Another invention described in U.S. patent application Ser. No. 09/740,701, entitled “Plating Method and Apparatus That Creates a Differential Between Additive Disposed on a Surface and a Cavity Surface of a Work Piece Using an External Influence”, filed Dec. 18, 2000, provides a method and apparatus for “mask-pulse plating” a conductive material onto a substrate by intermittently moving the mask, which is placed between the substrate and the anode, into contact with the substrate surface and applying power between the anode and the substrate during the process. Yet another invention described in U.S. patent application Ser. No. 09/735,546, entitled “Method of and Apparatus for Making Electrical Contact to Wafer Surface For Full-Face Electroplating or Electropolishing”, filed Dec. 14, 2000, now U.S. Pat. No. 6,482,307, provides complete or full-face electroplating or electropolishing of the entire wafer frontal side surface without excluding any edge area for the electrical contacts. This method uses an anode having an anode area, and electrical contacts placed outside the anode area. During the process, the wafer is moved with respect to the anode and the electrical contacts such that a full-face deposition over the entire wafer frontal surface is achieved. Another non-edge-excluding process described in U.S. patent application Ser. No. 09/760,757, entitled “Method and Apparatus for Electrodeposition of Uniform Film with Minimal Edge Exclusion on Substrate”, filed Jan. 17, 2001, also achieves full-face deposition with a system having a mask or a shaping plate placed between the wafer frontal surface and the anode. The mask contains asperities allowing electrolyte flow. In this system, the mask has a larger area than the wafer surface. The mask is configured to have recessed edges through which electrical contacts can be contacted with the front surface of the wafer. In this system, as the wafer is rotated, the full surface of the wafer contacts with the electrolyte flowing through the shaping plate, achieving deposition.
[0016] [0016]FIG. 2A shows a schematic depiction of a prior art electrodeposition system 30 . In this system, a wafer 32 is held by a wafer holder 34 with the help of a ring clamp 36 covering the circumferential edge of the wafer 32 . An electrical contact 38 is also shaped as a ring and connected to the (−) terminal of a power supply for cathodic plating. The wafer holder 34 is lowered into a plating cell 40 filled with plating electrolyte 42 . An anode 44 , which makes contact with the electrolyte 42 , is placed across from the wafer surface and is connected to the (+) terminal of the power supply. The anode 44 may be made of the material to be deposited, i.e. copper, or may be made of an appropriate inert anode material such as platinum, platinum coated titanium or graphite. A plating process commences upon application of power. In this plating system, the electrical contact 38 is sealed from the electrolyte and carries the plating current through the circumference of the wafer 32 .
[0017] [0017]FIGS. 1A through 1E show how the features on the wafer surface are filled with copper. For this filling process to be efficient and uniform throughout the wafer, it is important that a uniform thickness of copper be deposited over the whole wafer surface. Also, the resulting thickness uniformity of the plating process, i.e. the uniformity of thickness t3 in FIG. 1D and the uniformity of the thickness t5 in FIG. 1E, needs to be very good (typically less than 10% variation, and preferably less than 5% variation) because a non-uniform copper thickness causes problems during the CMP process.
[0018] As shown in FIG. 2B, in order to improve uniformity of the deposited layers, shields 46 may be included in the prior art electroplating system such as that shown in FIG. 2A. In such systems, either the wafer 32 or the shield 46 may be rotated. Such shields are described, for example, in U.S. Pat. No. 6,027,631 to Broadbent, U.S. Pat. No. 6,074,544 to Reid et al., and U.S. Pat. No. 6,103,085 to Woo et al. Further, in such systems, electrical thieves can be used for electrodepositing materials. Such thieves are described, for example, in U.S. Pat. Nos. 5,620,581 and 5,744,019 to Ang, U.S. Pat. No. 6,071,388 to Uzoh, and U.S. Pat. Nos. 6,004,440 and 6,139,703 to Hanson et al.
[0019] In view of the foregoing, there is a need for alternative electrodeposition processes and systems that deposit uniform conductive films and have the ability to change deposition rates on various portions of a substrate during the deposition process.
SUMMARY OF THE INVENTION
[0020] In one aspect of the present invention, a system for electrodepositing a conductive material on a surface of a wafer is provided. The system includes an anode, a mask having upper and lower surfaces, a conductive mesh positioned below the upper surface of the mask or shaping plate, and an electrolyte. The mask includes a plurality of openings extending between the upper and lower surfaces, and the mask is supported between the anode and the surface of the wafer. The conductive mesh is positioned below the upper surface of the mask such that the plurality of openings of the mask defines a plurality of active regions on the conductive mesh. The conductive mesh is connected to a first electrical power input. The liquid electrolyte flows through the openings of the mask and through the active areas of the mesh so as to contact the surface of the wafer.
[0021] Another feature of the invention is the provision of an apparatus which can control thickness uniformity during deposition of conductive material from an electrolyte onto a surface of a semiconductor substrate. The apparatus includes an anode which can be contacted by the electrolyte during deposition, a cathode assembly including a carrier adapted to carry the substrate for movement during deposition, a conductive element permitting electrolyte flow therethrough, and a mask lying over the conductive element. The mask has openings, permitting electrolyte flow therethrough, which define active regions of the conductive element by which a rate of conductive material deposition onto the surface can be varied. A power source can provide a potential between the anode and the cathode assembly so as to produce the deposition.
[0022] Preferably, the conductive element is a conductive mesh, and includes a plurality of electrically isolated sections. At least one isolation member or gap can separate the electrically isolated sections. The electrically isolated sections can be connected to separate control power sources.
[0023] In one configuration, the conductive element can be sandwiched between top and bottom mask portions which together define the mask. The conductive element could be placed under a lower surface of the mask. One of the electrically isolated sections may circumferentially surround another of the electrically isolated sections.
[0024] The electrically isolated sections could be irregularly shaped. Alternatively, one of the electrically isolated sections can be ring shaped while the other of these sections is disc shaped. The electrically isolated sections could additionally define adjacent strips.
[0025] At least one control power source can be used to supply a voltage to at least one of the electrically isolated sections to vary the rate of conductive material deposition onto a region of the substrate surface. In one configuration, the rate can be increased or decreased. Apparatuses such as those mentioned can be used to control thickness uniformity during conductive material deposition in a process including contacting the anode with the electrolyte, providing a supply of the electrolyte to the substrate surface through the conductive element and through the mask lying over the conductive element, providing a potential between the anode and the surface, and supplying a voltage to the conductive element in order to vary the conductive material deposition rate.
[0026] Uniform electroetching of conductive material on the wafer surface by reversing polarities of the anode and the cathode assembly is also within the scope of this invention. A process for establishing a relationship between deposition currents in active regions on the conductive mesh and thicknesses of the conductive material deposited onto the semiconductor substrate surface is also contemplated.
[0027] These and other features, aspects and advantages of the present invention will become better understood with reference to the drawings and the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] [0028]FIG. 1A is a partial sectional view of a semiconductor substrate with an overlying insulator layer including trenches and vias.
[0029] [0029]FIGS. 1B and 1C are cross sectional views illustrating a conventional method for filling trenches and vias, such as those of FIG. 1A, with a conductive material.
[0030] [0030]FIG. 1D is a cross sectional view showing a structure similar to that of FIG. 1C but after additional conductive material deposition.
[0031] [0031]FIG. 1E is a view similar to FIG. 1D but showing a structure with a reduced conductive material thickness over an insulator layer.
[0032] [0032]FIG. 2A is a schematic illustration, in cross section, of a known electrodeposition system.
[0033] [0033]FIG. 2B is a schematic illustration similar to FIG. 2A but showing a system which includes shields intended to improve deposition uniformity.
[0034] [0034]FIG. 3 is a schematic cross sectional illustration of one embodiment of an electrodeposition system according to this invention.
[0035] [0035]FIG. 4 shows the system of FIG. 3 when used to provide substantially flat conductive material deposition.
[0036] [0036]FIG. 5 is a top plan view of a conductive mesh, with irregularly shaped electrically isolated sections, which can be used in the embodiment of FIGS. 3 and 4.
[0037] [0037]FIG. 6A is an enlarged cross sectional view showing a combined mask and mesh structure in proximity with a front surface of a semiconductor substrate.
[0038] [0038]FIG. 6B is an enlarged view of section 6 B appearing in FIG. 6A.
[0039] [0039]FIG. 6C is a partial plan view along line 6 C- 6 C of FIG. 6B.
[0040] [0040]FIG. 7 shows another embodiment of a combined mask and mesh structure.
[0041] [0041]FIG. 8A is a top plan view of a conductive mesh similar to that of FIG. 5 but in which the electrically isolated sections are not irregularly shaped.
[0042] [0042]FIG. 8B shows the mesh of FIG. 8A as sandwiched between top and bottom mask portions in proximity with a front surface of a semiconductor substrate.
[0043] [0043]FIG. 9A is a top plan view of a conductive mesh with electrically isolated sections which define adjacent strips.
[0044] [0044]FIG. 9B is a view similar to that of FIG. 8B but showing the mesh of FIG. 9A as sandwiched between top and bottom mask portions.
[0045] [0045]FIG. 9C is a plan view along line 9 C- 9 C of FIG. 9B.
[0046] [0046]FIG. 10 is a schematic illustration of one system by which a mesh in accordance with any of the previously described embodiments can be energized.
[0047] [0047]FIG. 11 is a schematic illustration of another system in which multiple meshes are multiplexed through multiple switches.
[0048] [0048]FIG. 12 is an enlarged view of part of the system shown in FIG. 11.
[0049] [0049]FIG. 13 is a view similar to FIG. 12 showing a switch in a position by which copper is plated from a mesh onto a wafer as well as from an anode onto the wafer.
[0050] [0050]FIG. 14 is a view similar to FIG. 13 but showing the switch in a position by which copper is plated to the mesh so that less plating occurs on the wafer.
[0051] [0051]FIG. 15 is a schematic illustration of another system which can be used to correlate plating current to plated metal thickness measurements.
DETAILED DESCRIPTION OF THE INVENTION
[0052] The present invention provides a method and a system to control the uniformity of a conductive material layer deposited on a surface of a semiconductor. The invention can be used with ECMD, mask pulse plating and full face plating as well as plating systems that deposit conformal films. The deposition process of the present invention advantageously achieves deposition of a conductive material in a plurality of cavities, such as trenches, vias, contact holes and the like, on a surface of a semiconductor wafer.
[0053] As is known, during an electrodeposition process of a surface of a wafer, the current density applied to the surface is substantially greater at the periphery of the surface than the center of the surface. In the prior art, this higher current density results in an increased deposition rate of the deposited film at the periphery of the wafer as compared to the wafer center. With the present invention, the film thickness difference between the interior and the periphery of the wafer may be eliminated with use of the combination of the perforated plate or a mask and a conductive mesh of the present invention during the electrodeposition. The combination of the perforated plate and the conductive mesh facilitates uniform deposition of the conductive material.
[0054] Further, in another embodiment, the present invention achieves deposition of the conductive material through the combination of the perforated plate and the conductive mesh into the features of the surface of the wafer while minimizing the deposition on the top surface regions between the features by contacting, sweeping and/or polishing of the surface with the perforated plate of the present invention. For systems that can deposit planar films, i.e., ECMD, mask pulse plating and full face plating, the thickness uniformity can be controlled to a certain extent through designing the shape, size and location of the openings in the mask, pad or shaping plates that are employed. Although effective for a given process parameters, such approaches may not be flexible enough to have a dynamic control over the uniformity of the deposition process.
[0055] The apparatus and the process of the present invention exhibit enhanced deposition characteristics resulting in layers having flatness previously unattainable and conductive layers with materials characteristics surpassing that of prior art layers that have been produced using prior art processes and devices.
[0056] Reference will now be made to the drawings wherein like numerals refer to like parts throughout. As shown in FIG. 3, an electrodeposition system 100 of the present invention may preferably comprise a cathode assembly 102 and an anode assembly 104 . The system 100 may be used to deposit a conductive material such as copper on a semiconductor wafer such as silicon wafer. Although copper is used as an example, the present invention may be used for deposition of other common conductors such as Ni, Pd, Pt, Au and their alloys. The cathode assembly 102 of the electrodeposition system 100 may be comprised of a wafer carrier 106 , shown in FIG. 3 holding an exemplary wafer 108 , which is attached to a carrier arm 110 . The carrier arm may rotate or move the wafer 108 laterally or vertically.
[0057] The anode assembly 104 of the system 100 may be comprised of an anode 112 , preferably a consumable copper anode, a mask, and a conductive mesh 115 of the present invention. The mask, as shown, is in the form of a mask plate 114 . The anode 112 may preferably be placed into an enclosure such as an anode cup 116 which may be enclosed by the mask plate 114 and the conductive mesh 115 as in the manner shown in FIG. 3. The mask plate 114 and the mesh 115 are both perforated plates. The mask plate preferably comprises a first mask portion 114 a or a top mask portion and a second mask portion 114 b or a bottom mask portion. The mesh 115 may be interposed or sandwiched between the top and bottom portions 114 a , 114 b . The mask plate 114 may comprise a plurality of openings or asperities 117 which allow a copper plating electrolyte 118 to flow through the mask plate 114 and the mesh 115 , and wet the front surface 108 a of the wafer 108 and deposit material on the front surface 108 a of the wafer under applied potential. The asperities 117 in the top and bottom mask portions may generally be aligned to allow electrolyte flow through the top and bottom mask portions 114 a , 114 b . However, their partial alignment or placement in any other way that still allows electrolyte flow through the top mask portion 114 a to the wafer surface is also within the scope of this invention. During the electrodeposition process, the wafer surface 108 a may be kept substantially parallel to an upper surface 119 of the mask plate 114 and rotated. It should be understood that what counts is the relative motion between the wafer surface and the pad surface. This motion can be a rotational motion or a rotation motion with linear translation.
[0058] The mesh 115 may have first and second sections 115 a and 115 b that are electrically isolated from each other by an isolation member 115 c . The isolation member 115 c may be a gap separating both sections. The first section 115 a may be connected to a first control power source V 1 and the second section may be connected to a second control power source V 2 . If the control power supplies impart a negative voltage on the mesh sections, this results in some material deposition on the sections 115 a and 115 b during the electrodeposition, i.e. some deposition is “stolen” directly across from these sections. On the other hand, if a positive voltage is applied to the mesh with respect to the wafer surface, the section of the wafer across from the section of the mesh with positive voltage receives more plating. As will be described below, with the applied power V 1 and in combination with the functionalities of the mask asperities, the first section 115 a of the mesh 115 may, for example, control the thickness at the periphery of the front surface 108 a of the wafer 108 . In this respect, the second power V 2 on the second section 115 b controls the thickness on the center or near center regions of the front surface 108 a . During the deposition process, the electrolyte 118 is pumped into the anode cup 116 through a liquid inlet 121 in the direction of arrow 122 , and then in the direction of arrows 123 so as to reach and wet the surface 108 a of the wafer 108 which is rotated. The anode 112 is electrically connected to a positive terminal of a power source (not shown) through an anode connector 124 . The wafer 108 is connected to a negative terminal of the power source (not shown) . The anode 112 may have holes in it (not shown). Additionally, the anode may have an anode bag or filter around the anode to filter particles created during the deposition process. The mask plate 114 and the anode cup 116 may have bleeding openings (not shown) to control the flow of electrolyte.
[0059] As shown in FIG. 4, a planar electrodeposition process can also be employed. In this case, the cathode assembly 102 may be lowered toward the anode assembly 104 and the front surface 108 a of the wafer 108 is contacted with the upper surface 119 of the mask 114 while the wafer 108 is rotated. In this embodiment, the mask 114 may be made of a rigid material such as a hard dielectric material, or, optionally, the upper surface 119 of the mask 114 may contain rigid abrasive materials. During this process, addition of mechanical polishing or sweeping provides substantially flat deposition layers with controlled thickness.
[0060] [0060]FIG. 5 exemplifies the conductive mesh 115 and the sections 115 a and 115 b separated by the isolation member 115 c . The mesh 115 comprises openings 126 allowing electrolyte to flow through the openings. The mesh 115 may be made of platinum or platinum coated titanium mesh or other inert conductive materials. After a cycle of 5 to 50 uses, the polarity of the system may be reversed and the mesh can be cleaned for another cycle of uses. The number of possible cycles, before cleaning, depends on the use of the mesh and the size of the mesh. Although two regions are shown in FIG. 5, the use of more than two regions is within the scope of this invention.
[0061] As shown in FIGS. 6A-6C, the mesh 115 may be placed between the top and bottom mask portions 114 a , 114 b using suitable fastening means or may be formed as an integral part of the mask 114 . As shown in FIGS. 6B-6C, in side view and plan view respectively, when the mesh 115 and the mask 114 are combined, the openings 117 through the mask 114 define a plurality of active regions 130 on the mesh 115 . During electrodeposition, when a negative potential is applied to the mesh 115 , material deposition onto the active regions 130 occurs. If a positive voltage is applied, the active regions 130 of the mesh 115 become anodic and cause additional deposition on the wafer surface right above them. By varying the size and shape of the openings 117 , the size and shape of the active regions 130 are changed. This, in turn, varies the deposition rates on the front surface 108 a of the wafer 108 and hence alternatively controls the film thickness.
[0062] [0062]FIG. 7 illustrates another embodiment of a combined structure of the mask 114 and the mesh 115 . In this embodiment, the mesh 115 is placed under a lower surface 128 of the mask plate 114 . It is also within the scope of the present invention to position a plurality of meshes between the upper surface 119 and the lower surface 128 of the mask 114 . Each of a plurality of meshes may be isolated from each other with a layer of mask, and each mesh may have a sequentially applied different power during the electrodeposition process to control the deposition rate.
[0063] [0063]FIGS. 8A and 8B show another embodiment of the conductive mesh. In this embodiment, a mesh 131 comprises a first section 131 a and a second section 131 b isolated from one another by an isolation member 131 c . The first section 131 a is ring shaped and is fed by a first control power V 1 . As shown in FIG. 8B, the first section 131 a controls the deposition thickness at a periphery 132 of the wafer 108 . The second section 131 b , which is disc shaped, controls the deposition thickness at the center 134 of the wafer 108 by a second control power V 2 .
[0064] [0064]FIG. 9A-9C show another embodiment of a mesh 136 comprising a first section 136 a and a second section 136 b isolated from one another by an isolation member 136 c . The first and second sections 136 a , 136 b are both strip shaped and may be used with a mask 138 , which may have a circular or rectangular shape, having openings 140 . Similar to the previous embodiments, the mask 138 may comprise a top portion 138 a and a bottom portion 138 b , and the mesh 136 may be sandwiched between the top and bottom portions 138 a , 138 b . As shown in FIGS. 9B and 9C, the first section 136 a is aligned with a first end 142 of the mask 138 to control the deposition thickness at the periphery 132 of the wafer 108 which rotates during the electrodeposition process. The wafer 108 may be also moved in the direction Y. Similarly, the second section 136 b is aligned with the center 144 of the mask 138 to control the deposition thickness of the center 134 of the wafer 108 .
[0065] Of course, a uniform electroetching of the wafer surface by reversing polarities of the system 100 described above is also within the scope of this invention.
[0066] [0066]FIG. 10 shows one embodiment of energizing the sections of the mesh described in the previous embodiments. In this embodiment, an exemplary mesh 150 may be interposed between a top portion 152 a and a bottom portion 152 b of a mask plate. The mask plate comprises a plurality of asperities 154 defining active areas 156 on the mesh 150 . The mesh comprises a first or peripheral section 150 a and a second or central section 150 b which are isolated from one another by an isolation member 150 c . A first power source Va is connected to a wafer 158 , having a conductive surface 158 a and an anode of an anode cup (not shown) of an electrodeposition system such as those described with regard to FIGS. 3-4. The first power source Va may also be connected to the first section 150 a or the second section 150 b of the mesh 150 through a switch S 2 . A second power source Vb is connected to the wafer 158 and the first section 150 a or the second section 150 b of the mesh 150 through the switch S 1 .
[0067] Accordingly, if the switch S 1 connects node D to node A, no voltage is applied to the mesh 150 . If the switch S 1 connects node D to node B, a positive voltage is applied to the section 150 a of the mesh 150 . Accordingly, additional deposition is achieved in the section or sections AA on the wafer surface 158 a . Each section AA is positioned right across from a section 150 a of the mesh 150 . If the switch S 1 connects node D to node C, the section BB on the wafer receives the additional deposit.
[0068] If the switch S 2 connects node H to node E, regular deposition commences on the wafer surface 158 a . If switch S 2 connects node H to node G, section 150 a of the mesh 150 is rendered cathodic, and therefore attracts deposition, reducing the amount of deposit on the section AA of the wafer surface 158 a . Similarly, if S 2 connects node H to node F, deposition on the section BB of the wafer surface 158 a is reduced. Thus, the deposition rates in both sections AA and BB of the wafer can be controlled by selecting the proper positions for the switches S 1 and S 2 .
[0069] Only one power supply is required if one multiplexes the meshes M 1 , M 2 , M 3 . . . M n through switches S 1 , S 2 , S 3 . . . S n as shown in FIGS. 11-14. Also, measuring the current through a series of resistors would be useful for designing better mask patterns in the system. This is especially required for the present cell design because it is a complex cell to computer model and the potential field is not uniform across the system.
[0070] Everything can be done with one power supply if many switches are used, as shown in FIG. 11. For example, looking at one micro-plating cell M 1 as shown in FIG. 12, switch S 1 can be used to change the amount of deposition on the cathode section over micro-plating cell M 1 . In one case, shown in FIG. 13, when the switch S 1 is switched to the V A position, mesh M 1 is at potential V A , and copper plates both from the mesh to the cathode and from the anode to the cathode.
[0071] When the switch S 1 is switched to the V C position as shown in FIG. 14, the mesh M 1 is at a cathode potential and copper substantially plates to the mesh. To control thicknesses on different sections of the wafers, the duty cycles of switched meshes can be modulated in these regions.
[0072] If the switch S 1 is in the not connected (N C ) position, and is not connected to V A or V C , then copper will plate as in a normal system.
[0073] Substantially isolated meshes, one for each opening in the mash, can also be used to determine the local current density of each opening in the mesh. Measuring this is helpful in designing and testing new mask patterns to get optimized or better control on the plated thickness uniformity.
[0074] For one cell, referring to FIG. 15, in a first step, the voltage drop across the R 1 resistor is determined and the plating current for the particular cell is determined. This operation is then repeated in subsequent steps for every cell. Results are then mapped and compared to plated metal thickness measurements.
[0075] It should be understood, of course, that the foregoing relates to preferred embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. | An apparatus which can control thickness uniformity during deposition of conductive material from an electrolyte onto a surface of a semiconductor substrate is provided. The apparatus has an anode which can be contacted by the electrolyte during deposition of the conductive material, a cathode assembly including a carrier adapted to carry the substrate for movement during deposition, and a conductive element permitting electrolyte flow therethrough. A mask lies over the conductive element and has openings permitting electrolyte flow. The openings define active regions of the conductive element by which a rate of conductive material deposition onto the surface can be varied. A power source can provide a potential between the anode and the cathode assembly so as to produce the deposition. A deposition process is also disclosed, and uniform electroetching of conductive material on the semiconductor substrate surface can additionally be performed. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation, under 35 U.S.C. §120, of copending international application No. PCT/EP2013/074819, filed Nov. 27, 2013, which designated the United States; this application also claims the priority, under 35 U.S.C. §119, of German patent application No. DE 10 2012 222 019.4, filed Nov. 30, 2012; the prior applications are herewith incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a sealed plate heat exchanger comprising a frame body consisting of two frame plates, between which a plate stack of a plurality of heat exchange plates is arranged, means for feeding and discharging the heat exchange fluids that flow through the space between the heat exchange plates, and means for applying force to the frame plates, by way of which a pressure can be exerted on the plate stack.
[0003] Plate heat exchangers contain a stack of heat exchange plates, between which heat transfer takes place. These plates are generally provided with a profile or with flow ducts and through-openings for the media.
[0004] With plate heat exchangers, a basic distinction can be made between gasket-free and gasketed (sealed) designs. In the gasket-free configuration, the spaces between the plates are gasketed by the plates being rigidly connected, for example by welding, soldering or fusion technology.
[0005] In the gasketed designs, gaskets, generally elastomer-based gaskets, are used to seal and separate the media chambers between the different plates.
[0006] Depending on the media between which the heat exchange takes place, metals or metal alloys such as steel can be used as the material for the plates, or if the media are particularly corrosive, ceramic materials such as graphite or silicon carbide or fiber-reinforced ceramic materials can also be used.
[0007] Owing to their high brittleness, graphite-containing or ceramic plate materials such as graphite or silicon carbide place particularly high demands on the seal between the individual plates.
[0008] Such plate heat exchangers are generally produced in gasketed configurations owing to the brittleness of the graphite-containing or ceramic materials and to the fact that it is difficult to join these materials.
[0009] Moreover, gasketed plate heat exchangers are advantageous in that it is easier than in gasket-free configurations to separate the plates for removal or cleaning or for replacing individual plates.
[0010] In these plate heat exchangers in particular, a fluoropolymer, preferably based on polytetrafluoroethylene (PTFE), or graphite-based materials are generally used as the material for the gasket material. PTFE is highly ductile and only forms a low gasket thickness owing to its flow properties. As a result of this very low thickness of the gasket material, it is critical to ensure sufficient surface pressure on the gasket in order to achieve reliable sealing and to prevent leakages during operation.
[0011] The surface pressure is generally brought about by arranging the plate stack of the heat exchanger between two frame plates, between which the plates are clamped with an adequate force.
[0012] To apply the force for this clamping, tie rods are often used in combination with helical springs, which are arranged at a certain distance from the edge of the heat exchange plates.
[0013] European patent application EP 0 203 213 A1 (commonly assigned) describes plate heat exchangers constructed from at least three parallel plate elements which are spaced apart from one another and made of a corrosion-resistant material, and from means for feeding and discharging the heat exchange fluids which flow through the space between the plates, the plate elements being produced from a graphite body bound to a fluoropolymer.
[0014] German published patent application DE 10 2006 009 791 A1 describes a composite heat exchanger intended for use in the manufacture of chemical equipment and consisting of a metal frame body and a plate stack made of fiber-reinforced or monolithic ceramic, the stacked plates forming at least two duct systems which are arranged one above the other in any given number of layers in a manner separated by at least one plate and are delimited at opposite ends of the plate stack by cover plates which receive supply and outflow devices. In the regions surrounding the flow region and the through-openings for the media, the heat exchange plates comprise rectangular grooves in which sealing systems are arranged.
[0015] The structural configuration of the pressure-bearing components in commercially available gasketed plate heat exchangers, in particular those comprising plates based on graphite-containing or ceramic materials such as graphite, silicon carbide or fiber-reinforced ceramic materials, is only suitable for larger models to a limited extent, because when the size of the structure is increased, specifically when the plate width and/or plate length is increased, the bending of the frame plates is increased in the regions that are critical for sealing the heat exchanger, and leakages can thus occur in the heat exchanger.
SUMMARY OF THE INVENTION
[0016] It is accordingly an object of the invention to provide a plate heat exchanger in sealed configuration which overcomes the above-mentioned and other disadvantages of the heretofore-known devices and methods of this general type and which provides for a gasketed plate heat exchanger in which the above-mentioned problems are avoided or at least reduced.
[0017] With the foregoing and other objects in view there is provided, in accordance with the invention, a gasketed plate heat exchanger, comprising:
[0018] a frame body having two frame plates;
[0019] a plate stack of a plurality of graphite-containing or ceramic heat exchange plates disposed between the two frame plates;
[0020] means for feeding and discharging heat exchange fluids that flow through spaces formed between the heat exchange plates;
[0021] seals disposed for sealing between the heat exchange plates of the plate stack; and
[0022] force application devices configured to apply force to the frame plates of the frame body and for exerting pressure on the plate stack, wherein a centroid of a surface of at least one of the force application devices for applying force to the frame plate lies within an area produced from a linear projection of a surface area of the plate stack onto a corresponding the frame plate.
[0023] In other words, the gasketed plate heat exchangers according to the invention comprise a frame body consisting of two frame plates, between which a plate stack of a plurality of heat exchange plates is arranged, and means for feeding and discharging the heat exchange fluids that flow through the space between the heat exchange plates, means for applying force to the frame plates, by means of which a pressure can be exerted on the plate stack, and means for sealing between the heat exchange plates of the plate stack.
[0024] In contrast with the known heat exchangers of a similar construction, in the plate heat exchangers according to the invention at least one force application device is arranged such that the centroid of the surface for applying force to a frame plate is within the area produced from the linear projection of the surface area of the plate stack onto the corresponding frame plate. The term “centroid” is to be understood as the center of mass of the respective surface.
[0025] In the known plate heat exchangers having a gasketed configuration, the force is applied to the frame plates in such a way that force is applied to the frame plates via connecting elements which interconnect the two frame plates outside the surface area of the heat exchange plates, and thus a pressure is also exerted on the plate stack of the heat exchange plates. Here, the centroid of the force application surface is outside the area produced from the linear projection of the surface area of the plate stack onto the corresponding frame plate. Depending on the design, this construction results in bending of the frame plates as a result of the applied force, which is most pronounced in the central part of the frame plates. The frame plates bend more the wider and/or longer the frame plates are, i.e. the problem is more severe in larger heat exchangers than in smaller devices.
[0026] This bending leads to a sealing force or to a pressure on the gasket surface that is insufficient in the central region of the plate stack of the heat exchange plates to achieve perfect sealing in this region. Since the thickness of the gasket materials used is only very low, as mentioned above, this can result in mixing of the media between which heat is intended to be exchanged, and this leads to malfunction of the entire system and of all downstream units.
[0027] Hitherto, the aforementioned problems have limited the maximum size of plate heat exchangers of this design having heat exchange plates which are based on graphite, silicon carbide or other ceramic materials and produced in a gasketed construction.
[0028] The plate heat exchangers according to the present invention are distinguished in that at least one of the force application devices is arranged such that the centroid of the surface for applying force to a frame plate is within the area produced from the linear projection of the surface area of the plate stack onto the corresponding frame plate.
[0029] In the context of the present invention, the centroid of the force application surface is to be understood as being the geometric center of gravity of the corresponding surface that corresponds mathematically to the average of all the points in the area. The geometric center of gravity corresponds to the center of mass of a physical body which consists of a homogenous material. In symmetrical figures, this center of gravity can be obtained by appropriate geometric considerations; in the case of asymmetrical surfaces, it can be obtained by integration.
[0030] The center of gravity of a non-equilateral polygon can be calculated from the Cartesian coordinates of the corners; the center of gravity in regular polygons corresponds to the center of the circumcircle thereof.
[0031] In rectangles, parallelograms or squares, the center of gravity is obtained, for example, from the point of intersection of the diagonals. In triangles, the geometric center of gravity is the common point of intersection of the three medians. In circular surfaces, the geometric center of gravity is the center of the circle.
[0032] Therefore, when the shape of the force application surface is known, a person skilled in the art can determine the geometric center of gravity of the surface and design at least one force application device such that the geometric center of gravity of its force-applying surface is within the area produced from the linear projection of the surface area of the plate stack onto the corresponding frame plate.
[0033] In the context of the present invention, the surface area of the plate stack is to be understood as the area defined by the main dimensions of the plate stack or of the individual heat exchange plates. This surface area includes any notches, drilled holes, etc. present in the plate stack or in the individual heat exchange plates, and differs in this respect from the surface area of the plate stack which is defined by the outer contour of the plate stack or of the heat exchange plates and thus does not include any notches or recesses that may be present. Plate heat exchangers according to the invention comprise at least one force application device designed as described above, although it is also possible and covered by the present invention to design a plurality of force application devices in this manner.
[0034] Preferably, said force application device or said possible plurality of force application devices is/are arranged such that the force application surface is in the edge region of the surface area of the plate stack of the heat exchange plates, more preferably in the upper or lower region of the heat exchange plates, in which region the means for feeding and discharging the heat exchange fluids which flow through the space between the heat exchange plates are preferably also arranged. Good sealing is particularly essential in this region between the through-openings since this is where the heat exchange fluid flows are introduced into the plates, it being imperative to prevent said fluids from mixing or coming into contact with one another.
[0035] In principle, it would also be possible to arrange force application devices at different points such that the center of gravity of the force application surface is arranged according to the invention. Generally, however, the result of this would be that the ducts provided in the plates, in which ducts the fluid media flow, would accordingly have to be designed such that they are not disrupted by the force application devices. In addition, arranging the force application devices in this way would require providing the heat exchange plates with holes or openings in the region of the ducts, which is generally not preferable.
[0036] In general, therefore, it is more preferable to provide the force application devices such that none of the fluid-carrying ducts touch in the heat exchange plates of the plate stack.
[0037] Suitable force application devices in the plate heat exchangers according to the present invention are known per se to a person skilled in the art and are described in the patent literature, and there is therefore no need to go into further detail here. A person skilled in the art will use a suitable force application devices according to the respective application
[0038] According to one embodiment, the heat exchange plates can be provided with recesses or grooves, in which a sub-element, arranged between the frame plates, of a force application device is arranged. Said sub-element is guided through a hole or recess in the frame plates and end elements are connected to the sub-element such that a force can be exerted on the frame plate. Since the sub-element is arranged between the frame plates within the surface area of the heat exchange plates of the plate stack either completely or in part, the centroid of the force application surface of the corresponding means is within the area produced from the linear projection of the surface area of the plate stack or of the heat exchange plate onto the frame plate.
[0039] In an embodiment of this type, tie bolts are preferred force application devices. Tie bolts are understood in this case to be a means which can absorb tensile stresses. Preferably, tie bolts consisting of round metal rods are used, said tie bolts extending between the frame plates and comprising, at the end, devices which can be used to clamp the two frame plates with a defined force by means of the tie bolt. The precise structural design is selected depending on the respective application on the basis of specialist knowledge.
[0040] In the force application device, the centroid of the force application of which is within the area produced from the linear projection of the surface area of the plate stack or of the heat exchange plates onto the frame plate, the tie bolt arranged between the two frame plates is preferably positioned in a groove in the upper or lower side of the heat exchange plates, such that, in spite of the arrangement according to the invention of the force application devices, individual heat exchange plates can still be replaced without having to completely disassemble the plate heat exchanger. In principle, it is also possible for a blind hole to be provided in the upper region of the heat exchange plates, through which hole the tie bolt in guided. However, this then necessitates complete disassembly of the plate heat exchanger when replacing individual plates.
[0041] The tie bolt can be guided through the frame plates in a groove in a similar manner as in the heat exchange plates, or a corresponding hole can also be provided in the frame plate.
[0042] According to another embodiment of a plate heat exchanger according to the invention, the elements, arranged between the frame plates, of at least one force application device arranged according to the invention are designed such that they are located completely outside the surface area of the plate stack, or possibly even outside the surface area spanned by the frame plate. By means of an appropriate structural design, the force application onto the frame plate is designed according to the invention such that the requirement according to the invention is met. This can be achieved, for example, by the elements engaging around the frame plate in the manner of a clip and being attached to the frame plate such that the requirement according to the invention in terms of the centroid of the force application surface is met. Appropriate structural designs are known to a person skilled in the art, who will design a suitable means depending on the specific situation.
[0043] According to a further embodiment, at least two force application devices are interconnected on the frame plate by means of a clip or the like. This clip can then additionally be connected to the frame plate, for example in the center thereof, so as to apply force, whereby the center of gravity of the force application surface also comes to rest as required according to the invention.
[0044] According to a further, particularly preferable embodiment of the present invention, at least one of the frame plates comprises webs and/or ribs mounted thereon or rigidly connected thereto. Said webs or ribs further increase the stability and thus allow for use at even higher pressures. They can be produced from any material. Preferably, however, the webs and/or ribs are produced, in a similar manner as with the frame plates, from metals or metal alloys such as steel, or from plastics materials reinforced with fibers, in particularly carbon fibers, glass fibers or aramid fibers.
[0045] A person skilled in the art can design variants of the above-mentioned embodiments on the basis of his expertise. It is essential that the centroid of the force application surface of at least one force application device is within the area produced from the linear projection of the surface area of the plate stack or of the heat exchange plates onto the frame plate.
[0046] In structural terms, the connection dimensions of the means for feeding and discharging the fluid media and the type and shape of the force application devices create a minimum distance between the force application devices and the means for feeding and discharging fluid flows.
[0047] The shape of the force application surface is not subject to any particular restriction, but is preferably substantially rectangular, elliptical, circular, or in the shape of a regular polygon. Here too, a person skilled in the art will select and use a suitable means, in line with structural specifications, according to the desired application.
[0048] According to a preferred embodiment, the distance of the center of the force application device, the centroid of which is within the area produced from the linear projection of the surface area of the plate stack or of the heat exchange plates onto the frame plate, to the closest edge of the surface area of the stack of heat exchange plates is at least half the longest diagonal that can be formed in the force application surface.
[0049] According to a further preferred embodiment, the force application surface of the means does not intersect with the surface area of the closest means for feeding and discharging the fluid media.
[0050] Through-openings which are not restricted in any particular way in terms of cross section and which can be substantially circular, elliptical, rectangular, or in the shape of a polygon are preferably used as feeding and discharging means. The shape of the feeding and discharging means is not critical for the desired effect of improved sealing.
[0051] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0052] Although the invention is illustrated and described herein as embodied in a plate heat exchanger having sealed construction, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0053] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0054] FIG. 1 is a side view of a plate heat exchanger according to the invention;
[0055] FIG. 2 is a view of the region of a heat exchanger plate, in which it is possible to see the means for feeding and discharging the fluid media and the course of the sealing means provided between the plates;
[0056] FIG. 3 is a front view of the end face of a frame plate of a plate heat exchanger in which three force application devices are arranged according to the prior art; and
[0057] FIG. 4 is a corresponding view of a preferred variant of a plate heat exchanger according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0058] Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown a plate heat exchanger 1 according to the invention comprising a frame body 2 consisting of two frame plates 3 . A plate stack of heat exchange plates 4 is arranged between the frame plates 3 . A force application device 7 is also shown.
[0059] FIG. 2 shows the contours of a heat exchange plate 5 of a plate stack 4 (not shown) comprising means 6 for feeding and discharging fluid media and a sealing means 8 . It can be seen that the sealing means 8 separates the feeding means and discharging means 6 from one another in a sealed manner.
[0060] FIG. 3 shows the contours of a frame plate 3 and a heat exchange plate 5 and two means 6 for feeding and discharging fluid media, and three force application means or force application devices 7 denoted by way of black circles. It can be seen how the center of gravity of the force application surface in all the force application devices is outside the area produced by a linear projection of the surface area of the heat exchange plate 5 onto the frame plate 3 .
[0061] FIG. 4 shows the contours of a frame plate 3 and of a heat exchange plate 5 , means 6 for feeding and discharging fluid media, and a plurality of force application devices 7 . It can be seen how one force application device 7 (the one in the center of the upper row) is arranged such that the centroid of the force application surface thereof is completely within the area produced from the linear projection of the surface area of the heat exchange plate 5 or of the plate stack 4 (not shown) onto the frame plate 3 . FIG. 4 also shows a plate width B and a plate length L.
[0062] The material of the heat exchange plates 5 in the plate heat exchangers according to the invention can be selected by a person skilled in the art from the materials which are known for this purpose and described in the prior art. The advantages of the design according to the invention are particularly effective when the plates are made from a graphite body impregnated with a polymer, a graphite body bound to a polymer, or from silicon carbide or a composite fiber ceramic.
[0063] Preferred graphite-based materials preferably contain at least 50, more preferably at least 55 wt. % graphite.
[0064] Suitable materials as a graphite base in the form of polymer-bound graphite bodies can be obtained under the brand name Diabon® F, and graphite bodies impregnated with polymers, in particular with phenol resins, are commercially available under the brand name Diabon® NS, both from the company SGL Carbon of Wiesbaden, Germany.
[0065] Owing to the brittleness and material properties of all these materials, it is advantageous or necessary to design a plate heat exchanger which is to be built based on said materials in a gasketed construction, and the advantages of the present invention come into effect.
[0066] The advantages of the above materials are based on their extraordinarily high corrosion resistance and temperature resistance, for which reason plate heat exchangers made of such materials can be advantageously used in particular when corrosive media or high temperatures are used.
[0067] The frame plates 3 of the plate heat exchangers 1 according to the invention have to absorb significant forces owing to the clamping from the force application devices 7 , and therefore have to be structured to have corresponding levels of stability. Here too, a person skilled in the art will base their selection of the suitable material on the specific application of the plate heat exchanger 1 . On a merely representative basis, suitable materials for frame plates of the frame body 2 in this case are metals or metal alloys such as steel, or plastics materials reinforced with fibers, in particular carbon fibers, glass fibers or aramid fibers. It is primarily important in any case that the frame plates 3 can absorb the active forces such that the bending does not exceed certain limit values.
[0068] In any case, it is extremely important that the maximum bending generally reached in the center of the frame plate 3 is kept lower than the thickness of the sealing material used, otherwise leakages occur.
[0069] Since the materials used for sealing generally have a thickness of no more than 0.3 mm, preferably no more than 0.15 mm, the maximum bending of the frame plates 3 should also be below 0.3 mm, more preferably below 0.15 mm, to reliably ensure the leak-tightness of the plate heat exchanger 1 .
[0070] Any sealing material that has the appropriate corrosion-resistance for the desired use and guarantees durable sealing under operating conditions can be used as seals 8 . Preferred materials for the seals 8 are in particular fluorine-based polymers or graphite-based materials. Preferred fluoropolymers are polytetrafluoroethylene (PTFE) or polyvinylidene fluoride (PVDF). Appropriate materials are known to a person skilled in the art and are commercially available from many vendors.
[0071] According to a preferred embodiment, the gaskets used to achieve reliable sealing between each two heat exchange plates 5 can be designed as flat gaskets and inserted into peripheral grooves having a rectangular cross section. In this case, the thickness of the flat gaskets is selected such that said gaskets protrude out of the grooves and the leak-tightness is thus produced when the heat exchange plate stack 5 is clamped.
[0072] In principle, however, it is also possible to design the sealing means 8 as a sealing cord which can be placed in a simple manner between the heat exchange plates and guided through the force application to form a reliable seal.
[0073] The plate heat exchangers 1 according to the invention can be produced having larger plate widths B and/or plate lengths L than was possible hitherto in such products. Since the bending when force is applied via the corresponding clamps 7 increases as the plate width B and/or plate length L increases, until now plate heat exchangers having a gasketed construction and heat exchange plates based on graphite, silicon carbide or other ceramic or fiber-reinforced materials could only be produced having a limited size, which was determined on the basis that the maximum bending of the frame plates 3 was not permitted to exceed the above-mentioned values. By increasing the thickness of the frame plates 3 or increasing the rigidity of the materials, it is possible to obtain some improvement in this respect. Nevertheless, with the plate heat exchangers 1 according to the present invention, larger plate widths B and/or plate lengths L can be achieved in any case while using the same material, since the maximum bending can be considerably reduced owing to the arrangement, according to the invention, of at least one force application device 7 .
[0074] Tests have shown that the plate width B and/or plate length L can be increased by at least 20-30% without having to anticipate a higher degree of bending than in the plate heat exchangers of the same design according to the prior art. Therefore, under constant process conditions (pressure, temperature), a corresponding increase in the heat exchanger capacity can be achieved.
[0075] A further advantage of the plate heat exchangers 1 according to the invention is that the larger plate width B and/or plate length L allows the required footprint of the plate heat exchangers 1 to be considerably reduced for a desired heat exchange capacity, which is particularly advantageous in existing systems, of which the capacity is intended to be increased. These configurations often do not offer the possibility of providing a correspondingly larger footprint for increasing the heat exchanger capacity.
[0076] Overall, the plate heat exchangers 1 according to the present invention can therefore achieve heat exchanger capacities which, in relation to the required footprint for installing the corresponding heat exchanger, cannot be achieved by the heat exchangers of the same design according to the prior art.
[0077] The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:
[0078] 1 plate heat exchanger
[0079] 2 frame body comprising two frame plates
[0080] 3 frame plate
[0081] 4 plate stack consisting of heat exchange plates
[0082] 5 heat exchange plate
[0083] 6 means for feeding and discharging fluid media
[0084] 6 a through-openings
[0085] 7 force application device, force application means
[0086] 8 seal, sealing means
[0087] 9 recess or groove for receiving a sub-element
[0088] 10 a webs
[0089] 10 b ribs
[0090] B plate width
[0091] L plate length | A sealed plate heat exchanger includes a frame body with two frame plates and a plate stack between the frame plates. The plate stack is formed of a plurality of heat-exchange plates. Fluid channels allow feeding and leading away of heat exchange fluids that flow through the intermediate space between the heat-exchange plates. Devices for applying force to the frame plates, apply pressure to the plate stack. Seals are provided for sealing between the heat-exchange plates of the plate stack. A center of area of the area of the force application to the frame plate lies within an area that results from a linear projection of the area of the plate stack onto the frame plate. | 5 |
The U.S. Government has rights in this invention pursuant to Contract No. DE-AC04-76DP00789 between the U.S. Department of Energy and AT&T Technologies, Inc.
FIELD OF THE INVENTION
This invention relates to the mapping of thermal fronts associated with enhanced oil recovery operations by controlled source audio frequency magnetotelluric techniques, and to methods for enhancing the sensitivity of this technique.
BACKGROUND OF THE INVENTION
The mapping of thermal fronts associated with enhanced oil recovery (EOR) techniques from the surface has important application to improved reservoir stimulation. The present state of the art involves the drilling of monitor wells or the use of geophysical electromagnetic techniques. Monitor wells, however, can only provide local spot information, and the other techniques are not maximally effective nor sensitive.
U.S. Pat. No. 4,271,904 discloses a method of monitoring the progress and pattern of a combustion or flame front advancing through a combustible subterranean carbonaceous stratum, and for controlling the progress of the front. More particularly this patent teaches a method of monitoring the pattern and spatial orientation of a flame front during in situ retorting of oil shale, and injecting and controlling the flow of fuel or flue gases into the retort to control the speed, extent and uniformity of the flame front. The patented invention is based on a finding that rubblized shale makes a poor electrical coupling with the solid walls of the retort. However, as the shale burns, the flame front becomes a better electrical conductor. The front appears from the surface to be a plane of electrically conductive material embedded in the ground that changes position as the front moves. Resonance coil and resistance probe methods are suggested for electrical detection of the flame front.
The '904 patent also considers methods for controlling movement of the flame front. These involve the pumping of fuel and diluent gases through gas shafts into specified areas of the retort.
U.S. Pat. No. 3,986,556 to Haynes discloses the injection of a finely divided catalyst into a porous and permeable hydrocarbon bearing stratum in the earth. The catalyst promotes cracking of the heavy hydrocarbons within the reservoir, but there is no disclosure concerning monitoring the front as it progresses.
Controlled source audio frequency magnetotelluric surveys seek to map the shape and structure of objects below the surface of the earth from measurements made of the electromagnetic waves scattered by such an object. See generally, G. V. Keller and F. C. Triscknecht, Electromagnetic Methods in Geophysical Prospecting (New York: Pergamon Press, 1966), p 197; S. H. Ward Theory, Vol II of Mining Geophysics (The Society of Exploration Geophysicist, 1967), p 228; and W. M. Telford et al., Applied Geophysics (New York: Cambridge University Press), p 500.
For effective application of CSAMT surveying techniques to thermal front mapping, however, a substantial contrast in the resistivities of the surrounding media and the zone to be mapped must be present. Usually, this contrast must exceed that which is naturally inherent to the site to be surveyed.
SUMMARY OF THE INVENTION
In a method of use aspect, the present invention relates to a method for enhancing the resistivity contrasts of a thermal front produced by an enhanced oil recovery technique, to allow thermal front detection by a controlled source audio frequency magnetotelluric (CSAMT) technique. The method comprises the steps of: (a) removing core and conate water samples from the oil production recovery area; (b) selecting a dopant material having a high cation exchange capacity from the group consisting of montmorillonite, illite, and chlorite clays; said material being soluble in said conate water in sufficient concentration as to decrease the resistivity of the core sample by at least a factor of two while simultaneously remaining able to pass through said core without significantly plugging it as determined by a flowing permeability test; (c) preparing a CSAMT-determined topological resistivity map of the recovery area; (d) introducing a solution of said dopant material effective to alter the resistivity associated with the thermal front, which in the case of the steam flood technique is diluted from about 300:1 to 10:1 in water, into the injection well in a tertiary production field in an air/gas-to-water ratio by volume of about 1000 to 1; (e) preparing a CSAMT-determined topological resistivity map of the recovery area while said solution is flowing therethrough; and (f) mathematically comparing the maps from step (c) and step (e) to determine the location of the thermal front.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
This invention is directed to a method for enhancing the resistivity contrast of thermal fronts for mapping with controlled source audio frequency magnetotelluric techniques. Generally, a material with a high cation exchange capacity (CEC) is injected into an injection well at the beginning or during the lifetime of a flooding process (fire flood, steam flood, water flood, etc.). This material produces a bank of ions that will be swept along, forming the leading edge of the flood. The existence of these ions in the front will make the front much more conductive than it would have been without these ions, i.e., this region of lowered resistivity will serve as a marker of the leading edge of the front. This marker would then enhance the detection capability of any instrument on the surface of the earth used to measure electromagnetic changes within an underground stratum. The enhancement allows better resolution of fronts at shallower depths and allows fronts at deeper depths to be mapped. Knowing the location of the fronts thus provides effective control of the flooding process.
In the CSAMT technique, the primary electromagnetic (EM) field is produced by a long dipole (e.g., 610 m, 2000 ft) laid out on the surface of the earth and grounded at both ends. A transmitter operating at selected frequencies (for example, at about 42-2048 Hz) is located at the center of the dipole. The transmitting antenna is located some distance (e.g., 305-1520 m, 1000-5000 ft) from the area to be interrogated. For example, the receiving antenna might consist of a relatively short dipole (e.g., 2-20 m, 6-66 ft) in contact with the earth at both ends to measure the electric field parallel to the transmitting antenna and a magnetometer to measure the magnetic field perpendicular to the transmitting antenna and in the plane of the earth. Measurements of the electric and magnetic fields are made at various frequencies and at selected locations over the area to be interrogated. More accurate measurements can be made if several orientations are available.
The critical factor in applying the CSAMT method is the change in electrical resistivity of the oil zone during a thermal EOR process. For a steam flood, the presence of the heated water, especially after contamination by formation material, will lower the resistivity of the oil zone. As the high-resistance oil is removed from the zone and replaced with the injected steam/hot water, the resistivity should decrease even further.
The inverse appears to be true for a fire-front EOR process. As the fire front moves through a region, some of the in-place oil is first vaporized, and lighter fractions are carried ahead of the front by the combustion gases and the unused injected air. Thus, in front of the fire zone, water from the combustion process and stripped ground water are moved into the formation. This may result in a lowered resistivity. Behind the fire zone, the oil and water saturation are almost zero. There, only the high-resistance rock remains. Just in front of the fire zone, coke is formed and then consumed. The resistivity of the fire front will be variable, depending upon the complex combustion chemistry.
Thus, the signature for a steam drive will be an apparent low resistivity that rather quickly returns, at the edge of the steam front, to the background resistivity or lower. For a fireflood, the signature will be a zone of high resistivity that changes in a short distance to an area of lower resistivity, with a return to the background resistivity moving away from the injection well.
The ability to track in situ enhanced oil recovery processes using EM techniques is not a new idea. Kraft made a detailed model study in which he set up a finite element model of the physical conditions that might be encountered, G. D. Kraft, "Two Dimensional Finite Element Electrical Resistivity Modeling of Axially Symmetric Structures," M. S. Dissertation, Penn. State Univ., November 1976. One of the problems he studied was a highly conductive layer of resistive overburden. He indicated that the changes in the apparent resistivity were large enough to be measurable. However, for the pancake disk conductive zone considered, the changes in the resistivity, ρ a , did not correspond spatially with those of the disk. In this case, the conducting disk was at 600 meters (1,969 feet). Only when the conducting zone is much nearer to the surface would the changes in ρ a be expected to give a one-to-one mapping.
A detailed study by Goldstein and Strangway established limits for the most favorable application of the CSAMT mapping, M. A. Goldstein and D. W. Strangway, "Audio-Frequency Magnetotellurics with a Grounded Electric Dipole Source," Geophysics, Vol. 40 August 1975, pp 669-683. The resistivity ρ a in ohm-meters is related to two perpendicular components of the electric and magnetic field, e.g., E x and H y , by ##EQU1## where E x is in V/m, H y is measured in amp-turns/m, and f is the frequency in H z . The skin depth, Δ, the thickness of a homogeneous material of apparent resistivity ρ a required to attenuate the electromagnetic force (EMF) intensity by l/e, is given by ##EQU2## The EMF from the transmitting dipole can be divided into a near field (<3δ from the dipole) and a far field (>3δ ) because the functional dependency of the electric and magnetic fields changes with distance from the source. Only when measurements are made in the far field will the apparent resistivities calculated using Eq. (1) correspond to the true resistivities associated with plane-wave solutions of EM field equations. However, the near-field measurements yield a more sensitive indication of changes in formation resistivities.
Prior work by the inventors and their coworkers at Sandia National Laboratories, Albuquerque, N. Mex., in this area has been reported in Sandia Reports SAND 81-2497, March, 1982 "Sandia Heavy Oil Subprogram FY81 Annual Report", SAND 82-1699, Nov. 1982, "Measurements for the BETC in Situ Combustion Experiment", SAND 83-0117, April, 1983, "Sandia Heavy Oil Subprogram FY82 Annual Report, and in SPE 1051, a paper entitled "Measurement of Formation Resistivity Changes Induced by In-Situ Combustion", the latter paper being presented at the 57th Annual Fall Technical Conference and Exhibition of the Society of Petroleum Engineers of AIME, New Orleans, LA, Sept. 26-29, 1982. These prior reports provide details of work in this field leading to development of the present invention and the disclosure of these prior reports are specifically incorporated into this disclosure by reference.
With the foregoing theory in mind, the following discussion presents a preferred method for practicing the subject matter of the present invention.
Initially, a core sample material is taken from the oil field in which the thermal front recovery process is being, or will be, practiced. The core material is removed by conventional methods, and is typically sampled from several locations within the recovery area, preferably prior to the primary oil production processes. Thus, reference core samples may be available at the time that the tertiary recovery methods are begun. The core sample material typically includes a sand or carbonate matrix, along with oil, conate water and other fines, including minute trace materials of various types. For purposes of the present invention, only about 1 to 11/2 feet of core material are necessary along with approximately 1 liter or less of conate water. If core samples must be taken for the tertiary recovery methods described below, a conventional cutter is used that drills down through overlying formations, and is optimally extracted from one site near the middle of the recovery area. In oil fields known to have various core sample compositions, more than one core may preferably be prepared.
Next, a material having a high cation exchange capacity is selected that will flow through the core material without plugging. Generally preferred are clay materials such as montmorillonites, illites, and chlorites. These are conventional compounds known to have a high cation exchange capacity, and are composed of anhydrous aluminosilicates having a variable ionic content of heavy metals including iron and magnesium and other elements such as calcium and sodium. For the purposes of the present invention, other materials having a high cation exchange capacity may be equivalent, but generally speaking, the clay type materials mentioned above are adequate and preferred. Other cation exchange materials may be selected from the literature such as Lithology by Kern C. Jackson, published by McGraw-Hill, (1970), Table 3-1, page 100.
Because the chemistry of the core material is complex, a minimal amount of trial and error is necessary to select the appropriate cation exchange material that is optimally effective in a given core sample. However, the types of clay materials are generally found in several varieties, and are known in the art, and differ according to their source or origin. Using small aliquots of conate water, it is generally preferable to try five or six types of clays, most preferably of the montmorillonite type to determine the highest solubility of each type in a given sample of conate water. These cation exchange materials then are ranked in decreasing order of solubility.
Next, conventional flowing permeability tests are performed in a laboratory to determine which of the preferred, most soluble cation exchange materials flow through the core sample of about 1 to 11/2 feet in length, preferably without causing plugging or gumming. These flow tests are commercially run by various laboratories. For example, Core Labs, is a testing company with offices in all major oil field areas and routinely performs such testing.
Initially, several samples of conate water with a saturated level of the selected cation exchange material are run through the core sample. The purpose of this testing is to avoid selecting a dopant cation exchange material that may significantly change the permeability of the rock in situ in the reservoir. If the selected cation exchange materials cause plugging of the test core sample in saturated solution, their concentrations are decreased gradually in order to determine the maximum concentration at which a given cation exchange material will flow without plugging when dissolved in the conate water.
Once acceptable concentrations of the preferred and ranked materials having high cation exchange capacity have been determined, the resistivity of the core sample is also measured in the laboratory while a given conate sample having one of the cation exchange materials is flowing through it.
The measured resistivity of the core material sample generally changes while the conate material with dopant is flowing through it, optimally a change by a factor of 5 is preferred; however, decreased resistivity by a factor of up to 1000 has been achieved in the laboratory. Impedance bridges such as the conventional four-point resistivity bridge may be utilized for purposes of laboratory resistivity measurements. The Hewlett-Packard Company makes such impedance bridges, and other sources for this equipment are known to workers in the field.
For use in the field, the selected cation exchange material is prepared by diluting the optimized concentration in conate water by a factor of from about 300:1 to 10:1, preferably from about 100:1 to 10:1. The dilutions are made in water. Although more concentrated solutions are effective in the methods of the present invention, saturated solutions and those of higher concentration are generally too expensive, and dilutions of about 100:1 work effectively in the field. Because the material having the high cation exchange capacity is introduced into the tertiary recovery area for a time period of ten days to about two weeks, an adequate reservoir of doped solution must be prepared and stored on site.
Once the dopant solution is selected and prepared, its use in the field varies somewhat depending on the type of tertiary recovery process involved. For example, if the steam flood technique is to be utilized, the dopant solution is injected in line with the steam to be introduced through the injection well. Generally, there is a steam generator in line at the top of the well which enters the injection well through a series of pipes and valves, etc., known as the "christmas tree". The dopant solution is injected into a selected valve, typically under pressure, so that it mixes with and is vaporized into the steam stream and carried down-hole into the formation. A continuous flow of steam and dopant solution is maintained while measurements are made over the approximately 10 day to two week period of the testing. Preferably, many tests would be made to detect the first pass of the thermal front once the cation exchange material has been introduced. However, this practice is not cost effective. In practice, while the dopant is being injected, many CSAMT measurements are made from the surface and the data analyzed, as discussed below. A map of the resistivities of various sites within the recovery area is also made, prior to introduction of the dopant, as a control.
Once the dopant is introduced into the injection well, the steam associated with this recovery technique interacts with the oil and other materials in the oilbearing underground formation. The oil and other hydrocarbons are volatilized and driven by the force of the steam away from the injection well. Several production wells, sometimes referred to as collection wells, are located in a particular pattern around the injection well. For example, the 5-spot pattern is commonly utilized in the field. Various types of injection production well systems are disclosed, for example, in U.S. Pat. Nos. 3,986,556 and 4,271,904. Thus, the steam introduced into the injection well forces its way through the underground formation toward the production well, and usually is injected at a constant rate. The steam condenses along the thermal front, which is the zone at which the steam condenses into water. This front moves at a slower rate away as the distance from the injection well increases. It is the location of this thermal front to which the methods of the present invention are directed.
At the thermal front, typically, the resistivity drops as the dopant solution moves past. As resistivity measurements are made by the CSAMT technique following the commencement of the introduction of materials having high cation exchange capacity, a topological map of the recovery area is made. These resistivity measurements are compared with those of the same sites prior to commencement of the test. The background, or control measurements, are divided into the new measurements, and where the resistivity drops (i.e., regions where the data ratio is less than one), this indicates the location of the thermal front. Where the ratio remains constant, this indicates that steam has not passed by that point.
The data is gathered during an approximately ten day to two week time period, which is required to map a large field. As noted above, doped solution is injected into the steam line for the entire testing duration. The map which is prepared may have up to about 300 to 400 positions and 2,000 to 3,000 data points are commonly gathered. As discussed above, the thermal front represents the point at which colder rock condenses the steam. This leading edge also indicates the point to which petroleum or conate water has been driven. Data analysis of the location of the thermal front provides useful data for several purposes. Primarily, it identifies the location of the thermal fronts to monitor production from the recovery area. Additionally, by determining the areas into which steam has flowed, it allows chemicals to be introduced into the steam flow in order to plug those parts of the reservoir where steam is undesirably flowing, i.e., by conventional blocking techniques. Additionally, it allows for the optimized placement of production wells in order to efficiently tap the petroleum volatilized and driven forward by the steam flood procedure.
The two general types of steam flood techniques--the steam flood which involves a continuous flow of steam, and the "huff and puff" which involves a two to three month steam treatment with interspersed three month soaking periods--are effectively monitored by the methods of the present invention. Additionally, water flood tertiary recovery procedures may also be utilized for purposes of the present invention, and for this procedure water containing the doping cation exchange materials are dissolved into the water introduced through the injection well. The various techniques of the fire flood procedure may also be utilized with the methods of the present invention. These include the dry-forward, wet-forward and reverse combustion procedures.
A typical dopant solution may include, for example about 5 to 100, preferably about 10 milligrams per liter, of the dopant in water. This solution would then be introduced such as in a stream flow, for example, in a gas/air-to-water ratio by volume of about 1000 to 1. This will decrease the resistivity at the thermal front by a substantial amount, perhaps by a factor of up to about 10,000. Model calculations indicate that this will then increase the existing sensitivity of CSAMT surveys of thermal fronts by a factor of up to about 100. In addition, because a series of measurements could be made before and also during the dopant-water injection, the exact location of the thermal front can be found by simple subtraction or renormalization techniques. Thus, locating the thermal front is greatly facilitated by the methods of the present invention.
CSAMT equipment necessary for monitoring is commercially available and well known in the art. There are several CSAMT equipment packs available on the market, some being microprocessor controlled and facilitate the data collection component of the procedure. Field grade equipment is also available, as are basic components of the CSAMT system which are commercially available from the Zonge ENG. Co., for example.
The following example is presented to illustrate the invention and is not considered to be limiting thereon. Parts are by weight unless unless otherwise indicated.
EXAMPLE
In this experiment, the resistivity of the formation was measured as a fire front passed through in a dry forward burn as described for example in Sandia Report No. 82-874, J. R. Wayland, D. O. Lee, P. C. Montoya, "Measurement of Resistivity Changes Induced by In Situ Combustion". There was a two decade increase as the firefront moved past the measuring electrodes. Water was then injected which contained 10 milligrams per liter of montmorillonite clay with an air-to-water ratio by volume of 100 to 1. The resistivity of the firefront decreased by a factor of 10 4 . Thus the improvements of the inventive method are apparent.
From the foregoing description and discussion, one skilled in the art can easily ascertain the central characteristics of this invention. For the purposes of the methods of the invention, the exact composition of the cation exchange material is not critical, as long as the material has a high exchange capacity and flows effectively through core material samples, thereby increasing the laboratory measurements of resistivity in the sample. Accordingly, and without departing from the spirit and scope of the invention discussed above, various changes and modifications of the methods of the present invention may be made to adapt them to various particular usages and conditions. Thus, the the foregoing discussion of the preferred specific embodiments are, therefore, to be construed as merely illustrative and not limitative of the disclosure in any way whatsoever. | A method for enhancing the resistivity contrasts of a thermal front in an oil recovery production field as measured by the CSAMT technique is disclosed. This method includes the steps of:
(a) preparing a CSAMT-determined topological resistivity map of the production field;
(b) introducing a solution of a dopant material into the production field at a concentration effective to alter the resistivity associated with the thermal front; said dopant material having a high cation exchange capacity which might be selected from the group consisting of montmorillonite, illite, and chlorite clays; said material being soluble in the connate water of the production field;
(c) preparing a CSAMT-determined topological resistivity map of the production field while said dopant material is moving therethrough; and
(d) mathematically comparing the maps from step (a) and step (c) to determine the location of the thermal front.
This method is effective with the steam flood, fire flood and water flood techniques. | 4 |
FIELD OF THE INVENTION
The invention relates to the technical field of plate bending, in particular to a full-automatic luminous character enclosing machine used for enclosing edge of a stereoscopic luminous character.
BACKGROUND OF THE INVENTION
In recent years, stereoscopic luminous characters become the first choice for billboards because of their attractive and high-grade appearances and low cost. The edge of a stereoscopic luminous character is usually made to form a grooved character with an aluminum alloy sheet and a stainless steel sheet, and the intermediate part is filled by an LED luminous board or a common plastic sheet. The main work of making a stereoscopic luminous character edge is edge enclosure which mainly includes edge bending and arc curving. Traditional edge bending and arc curving are manual processes or using a cutting blade to carry out grooving followed by machining, thereby costing time and labor and having ugly appearance. Using a stainless steel sheet to make a grooved character requires high-pressure water jet to make a hollow-out character, and the high-pressure water jet has the power usually over 10 KW and is not so fast in cutting speed, therefore its cost is high and energy consumption is large. After the hollow-out character is made by cutting, an edge band needs to be welded to form a character shell. Edge band welding costs time and labor and has heat emission. Some advertisement companies use very thick stainless steel for making a hollow-out character to show their high-grade produces, and it costs long cutting time and high energy consumption. In order to provide a special device, the applicant has disclosed a stereoscopic luminous character enclosing machine (patent No.: 200710113527.5), which includes a feeding unit mounted on a main board of a machine body, a groove-cutting unit and an arc-curving unit, wherein the groove-cutting unit includes a traversing rack and an elevating rack mounted on the traversing rack, the traversing hack and the elevating rack are respectively driven by a motor through a ball screw, a motor-driven saw disc is mounted on the elevating rack, an arc-curving pressure roller elevating unit is mounted on the traversing rack, and an arc-curving pressure roller capable of passing through the main board of the machine body is disposed on the upper end of the arc-curving pressure roller elevating unit. This luminous character enclosing machine has the disadvantages as follows: first, heat is easily generated during cutting due to use of the saw disc for grooving, resulting in discoloration of a stainless steel band, and thus the machine is not suitable for groove-cutting of a stainless steel band; second, when a luminous character edge is completed, manual breaking is needed, which is unfavorable for automatic operation of the whole machine.
SUMMARY OF THE INVENTION
The object of the invention is to provide a luminous character enclosing machine suitable for making a stainless steel luminous character edge.
In order to realize the object, the provided luminous character enclosing machine includes an upper supporting plate and a lower supporting plate which are installed on a machine frame, and a plate inlet and a plate outlet are formed respectively on two ends of the upper and lower supporting plates. A feeding unit and an arc-curving unit are arranged in succession from the plate inlet to the plate outlet. The machine is structurally characterized in that a grooving unit and a plate-clamping unit mounted between the upper supporting plate and the lower supporting plate are disposed between the feeding unit and the arc-curving unit, and in addition, a grooving driving device for driving the grooving unit to move is mounted on the machine frame.
With the above structure, because the grooving unit and the plate-clamping unit arranged between the upper supporting plate and the lower supporting plate are disposed between the feeding unit and the arc-curving unit, and the machine frame is further provided with the grooving driving device for driving the grooving device to move and can control the grooving driving device to drive the grooving unit to move up and down, the grooving unit can groove a plate when doing up-down movement. Since such grooving mode is cold processing mode, it can neither cause discoloration of the stainless steel plate due to heat generation, nor result in knife broken due to high speed rotation of a saw blade and the hardness of the stainless steel. The invention is simple in structure and convenient to operate and especially suitable for grooving of a stainless steel character edge.
The grooving unit includes a vertical plate fixedly mounted between the upper supporting plate and the lower supporting plate, the vertical plate is connected to a tool holder which is capable of sliding vertically, a grooving tool is mounted on the tool holder, and the lower end of the tool holder is dynamically connected to the grooving driving device.
The grooving driving device includes a main motor fixedly mounted on the lower part of the machine frame, a gear is disposed on the power output shaft of the main motor, the lower part of the tool holder is provided with a rack engaged with the gear, and both sides of the rack is provided with guide fixing plates fixedly mounted on the machine frame.
As an improvement of the invention, a tool feed adjusting unit is further mounted on the vertical plate and includes an adjusting plate parallel to the vertical plate, the adjusting plate is connected to the vertical plate via a guide pin, the tool holder is slidably connected to the adjusting plate, an adjusting cylinder is mounted on the outer side surface of the vertical plate, the piston rod of the adjusting cylinder can pass through the vertical plate and extends to the adjusting plate, and a rubber spring is mounted on the guide pin positioned on the inner side of the adjusting plate.
The plate-clamping unit includes a back plate mounted between the upper supporting plate and the lower supporting plate, guide bolts capable of sliding pass through and are mounted on the back plate, pressure plates are fixedly disposed on the inner ends of the guide bolts, the outer end of the guide bolts are fixedly connected to a cylinder, the piston rod of the cylinder is capable of extending to the back plate, and springs are arranged between the pressure plates and the back plate.
The arc-curving unit includes guide rollers which are oppositely and fixedly disposed between the upper supporting plate and the lower supporting plate, the guide rollers provide a passage for a plate to pass through, arc-curving sleeves are sleeved outside the guide rollers, the front parts of the arc-curving sleeves form a plate inlet, the guide rollers have guide plates extending towards the plate inlet, the rear parts of the arc-curving sleeves form a corresponding plate outlet, the transverse width of the plate inlet is much larger than the width of the plate outlet, the side walls of the arc-curving sleeves at the outlet of the passage are respectively provided with press-curving rolling balls capable of rolling, and the arc-curving sleeves are dynamically driven by a servo motor fixedly mounted under the machine frame.
As a further improvement of the invention, a shearing unit is also mounted on the machine frame and includes a rotating shears mounted between the upper supporting plate and the lower supporting plate, the rotating shears is formed by an inner cylinder and an outer cylinder which coaxially rotate and are sleeved together, the front parts of the inner cylinder and the outer cylinder form a plate inlet, the cylinder /ails of the rear parts of the inner cylinder and the outer cylinder are oppositely provided with cutting edges, the outer surfaces of the lower parts of the cylinder walls of the inner cylinder and the outer cylinder are respectively provided with a transmission gear, the lower part of the cylinder wall of the outer cylinder is provided with a notch capable of exposing the lower part of the cylinder wall of the inner cylinder, both sides of the outer cylinder are respectively provided with a transmission rack engaged with the transmission gear, and the transmission racks are dynamically driven by a shearing motor to move in the same direction.
The inner cylinder is sleeved outside the arc-curving sleeves and coaxial with the arc-curving sleeves.
A groove-cutting unit is further mounted on the machine frame and positioned between the feeding unit and the grooving unit, the groove-cutting unit includes a supporting frame and a pressure plate device which are mounted on the machine frame, and an elevating device, a rotating device and a cutting device are mounted on the supporting frame.
The elevating device includes an elevating motor mounted on the machine frame, a transmission belt in transmission connection with the elevating motor, and an elevating frame slidably mounted on the supporting frame, wherein the elevating frame is fixedly connected with the transmission belt, and the other end of the transmission belt is provided with an iron counterweight through a pulley; the rotating device includes a rotating motor fixedly mounted on the elevating frame, and a turn table is disposed on the power output shaft of the rotating motor; the cutting device includes a cutting motor fixedly mounted on the turn table, the cutting motor is in a transmission connection with a cutting tool holder, the cutting surface of the cutting tool holder and the axial line of the power output shaft of the rotating motor are in the same plane; the pressure plate device includes a support connection plate mounted between the upper supporting plate and the lower supporting plate, rotating pressure feet are mounted on the support connection plate and fixedly disposed between the upper supporting plate and the lower supporting plate via rotating shafts, springs are arranged between the rotating pressure feet and the support connection plate whereby a plate passage is formed between the pressure feet and the support connection plate, the lower parts of the rotating pressure foot abut against a pressing plate articulated on the lower supporting plate, and the lower part of the pressing plate abuts against a pressing can driven by a groove-cutting pressure motor.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is further described in connection with the accompanying drawings:
FIG. 1 is a structure diagram of the invention;
FIG. 2 is a structure diagram taken in A direction in FIG. 1 ;
FIG. 3 is a structure diagram taken in B direction in FIG. 1 ;
FIG. 4 is a structure diagram taken in C direction in FIG. 1 ;
FIG. 5 is a structure diagram taken in D direction in FIG. 1 ;
FIG. 6 is a structure diagram taken in E direction in FIG. 1 ; and
FIG. 7 is a sectional structure diagram taken along F-F in FIG. 6 .
Wherein, 1 is machine frame, 2 is upper supporting plate, 3 is lower supporting plate, 4 is main motor, 5 is gear, 6 is rack, 7 is grooving head, 8 is guide fixing plate, 9 is guide roller, 10 is cut groove, 11 is vertical plate, 12 is inner cylinder, 13 is tool holder, 14 is back plate, 15 is pressure plate, 16 is cylinder, 17 is top spring, 18 is guide bolt, 19 is electric control cabinet, 20 is adjusting plate, 21 adjusting cylinder, 22 guide pin, 23 is guide plate, 24 is arc-curving sleeve, 25 is servo motor, 26 is groove-cutting pressure motor, 27 outer cylinder, 28 is cutting edge, 29 is transmission gear, 30 is transmission rack, 31 is shearing motor, 32 is supporting frame, 33 is elevating motor, 34 is transmission belt, 35 is elevating frame, 36 is iron counterweight, 37 is rotating motor, 38 is turn table, 39 is cutting motor, 40 is cutting tool holder, 41 is raw material rotary disc, 42 is guide wheel group, 43 is driving roller, 44 is driving motor, 45 is support connection plate, 46 is rotating pressure foot, 47 is spring, 48 is rotating shaft, 49 is pressing plate, 50 pressing cam, 51 is slide rail, 52 is slide block, 53 is rubber spring, 54 is press-curving rolling hall, 55 is notch, 56 is grooving tool, 57 is grooving tool fixing plate, and 58 is positioning sleeve.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The luminous character enclosing machine as shown in the drawings includes an upper supporting plate 2 and a lower supporting plate 3 which are mounted on a machine frame 1 oppositely, the left sides of the upper supporting plate and the lower supporting plate form a plate inlet, and the right sides of the upper supporting plate and the lower supporting plate form a plate outlet. A feeding unit, a groove-cutting unit, a grooving unit, an arc-curving unit and a shearing unit (the positions of the groove-cutting unit and the grooving unit can be exchanged, and the positions should be determined to facilitate convenient installation and maintenance) are disposed in succession on the upper supporting plate and the lower supporting plate from the left to the right. The feeding unit includes a raw material rotary disc 41 fixedly mounted on the lower supporting plate 3 and provided with a plate-stretch opening, guide wheel groups 42 are correspondingly arranged in pair between the upper supporting plate and the lower supporting plate, four to six groups of driving rollers 43 are disposed between the upper supporting plate and the lower supporting plate and dynamically driven by a driving motor 44 , the driving motor 44 is fixedly mounted on the machine frame 1 and drives the driving rollers 43 to rotate through a gear-rack transmission mechanism, and the driving rollers in each group are arranged oppositely and rotate in opposite directions to drive a plate to move forward. A grooving driving device and a plate-clamping unit are disposed on the machine frame 1 , as shown in FIGS. 1 , 3 , 4 and 5 , a vertical plate 11 is arranged between the upper supporting plate and the lower supporting plate, the grooving driving device includes a maim motor 4 fixedly mounted under the machine frame 1 , the power output shaft of the main motor 4 is equipped with a gear 5 , a tool holder 13 is slidably connected to the vertical plate 11 , the lower part of the tool holder 13 is provided with a rack 6 which is engaged with the gear 5 , both sides of the rack 6 are provided with guide fixing plates 8 which are fixedly mounted on the machine frame 1 to ensure engagement between the rack 6 and the gear 5 whereby the rack 6 drives the tool holder 13 to move up and down, and the guide fixing plates 8 are fixedly on the machine frame 1 . The vertical plate 11 is equipped with a tool feed adjusting device which includes an adjusting plate 20 parallel to the vertical plate 11 , a vertical slide rail 51 is disposed on the adjusting plate 20 , the tool holder 13 is provided with a slide block 52 slidably fitted with the slide rail 51 , a grooving tool 56 is fixedly mounted on the tool holder 13 , an adjusting cylinder 21 is mounted on the outer side surface of the vertical plate 11 , the piston rod of the adjusting cylinder 21 can passes through the vertical plate 11 and extends to the adjusting plate 20 , a rubber spring 53 is disposed on a guide pin 22 positioned on the inner side of the adjusting plate 20 to ensure the distance and parallelism between the vertical plate 11 and the adjusting plate 20 , and a positioning sleeve 58 is also mounted on the guide pin 22 positioned between the vertical plate 11 and the adjusting plate 20 . The plate-clamping unit includes a back plate 14 fixedly mounted between the upper supporting plate and the lower supporting plate, a pair of pressure plates 15 which are symmetrically disposed and a cylinder supporting frame for a cylinder 16 are respectively mounted on both sides of the back plate 14 and guidably fixed via guide bolts 18 , the upper part and the lower part of the back plate 14 are respectively provided with four slidable guide bolts 18 , the inner ends of the guide bolts 18 are fixed to the pressure plates 15 , the outer ends of the guide bolts 18 are fixedly connected to the cylinder supporting frame, the piston rod of the cylinder 16 passes through the cylinder supporting frame and can extend to the back plate 14 , the two pressure plates 15 respectively correspond to the upper end and the lower end of the back plate 14 , the two pressure plates 15 and the upper part and the lower part of the back plate 14 are correspondingly provided with counterbores in which springs 17 are fixedly mounted to enable the pressure plates 15 and the hack plate 14 to form a plate passage between thereof, and the guide bolts 18 pass through the springs 17 . When the cylinder 16 is inflated, the piston rod of the cylinder acts on the back plate 14 , and then the pressure plates 15 comes close to the hack plate 14 along the lower supporting plate 3 to clamp a plate.
Referring to FIG. 6 and FIG. 7 , the arc-curving unit includes guide rollers 9 fixedly mounted between the upper supporting plate and the lower supporting plate, the guide rollers 9 provide a passage for a plate to pass through, arc-curving sleeves 24 are sleeved outside the guide rollers 9 , the front parts of the arc-curving sleeves 24 form a plate inlet, guide plates 23 extending to the plate inlet are arranged on the guide rollers 9 , the rear parts of the arc-curving sleeves 24 form a corresponding plate outlet, the transverse width of the plate inlet is much larger than the width of the plate outlet, the side wall of the arc-curving sleeves 24 at the outlet of the passage are respectively provided with press-curving rolling balls 54 capable of rolling, and the arc-curving sleeves 24 are dynamically driven by a servo motor 25 fixedly mounted under the machine frame 1 . A shearing unit is also mounted on the machine frame 1 and includes a rotating shears mounted between the upper supporting plate and the lower supporting plate, the rotating shears is formed by an inner cylinder 12 and an outer cylinder 27 which coaxially rotate and are sleeved together, the front parts of the inner cylinder 12 and the outer cylinder 27 form a plate inlet, the cylinder walls of the inner cylinder 12 and the outer cylinder 27 are oppositely provided with cutting edges 28 , the outer surfaces of the lower parts of the cylinder walls of the inner cylinder 12 and the outer cylinder 27 are respectively provided with a transmission gear 29 , the lower part of the cylinder all of the outer cylinder 27 is provided with a notch 55 capable of exposing the lower part of the cylinder wall of the inner cylinder 12 , both sides of the outer cylinder 27 are respectively provided with a transmission rack 30 engaged with the transmission gear 29 , the transmission racks 30 are dynamically driven by a shearing motor 31 to move in the same direction, the shearing motor 30 drives two rotating wheels in opposite directions to drive the transmission racks 30 such that the two transmission racks 30 can move in the same direction, the outer cylinder 27 is sleeved outside the arc-curving sleeve 24 and coaxial with the arc-curving sleeves 24 , and alternatively, the shearing unit and the arc-curving unit can be disposed separately such that a plate can be sheared after being arc-bent, so the operations of edge bending and arc curving of a stereoscopic luminous character edge is completed.
As shown in FIG. 1 and FIG. 2 , the groove-cutting unit includes a supporting frame 32 and a pressure plate device which are mounted on the machine frame 1 , and an elevating device, a rotating device and a cutting device are mounted on the supporting frame 32 . The elevating device includes an elevating motor 33 mounted on the machine frame 1 , a transmission belt 34 which is in transmission connection with the elevating motor 33 , and an elevating frame 5 slidably mounted on the supporting frame 32 , wherein the elevating frame 35 is fixedly connected with the transmission belt 34 , and the other end of the transmission belt 34 is provided with an iron counterweight 36 through a pulley; the rotating device includes a rotating motor 37 fixedly mounted on the elevating frame 35 , and a turn table 38 is disposed on the power output shaft of the rotating motor 37 ; the cutting device includes a cutting motor 39 fixedly mounted on the turn table 38 , the cutting motor 39 is in a transmission connection with a cutting tool holder 40 , a cutting shaft where the cutting tool holder 40 is positioned is fixedly mounted on two fixing plates which are fixedly disposed below the turn table 38 , a cutting blade is mounted on the cutting tool holder 40 , and the cutting surface of the cutting tool holder 40 and the axial line of the power output shaft of the rotating motor 37 are in the same plane; the pressure plate device includes a support connection plate 45 mounted between the upper supporting plate and the lower supporting plate, a pair of rotating pressure feet 46 are symmetrically mounted on the support connection plate 45 and fixedly disposed between the upper supporting plate and the lower supporting plate via rotating shafts 48 , springs 47 are arranged between the rotating pressure feet 46 and the support connection plate 45 whereby a plate passage is formed between the pressure feet 46 and the support connection plate 45 , a pressing plate 49 tightly abuts against the lower parts of the rotating pressure feet 46 , the middle part of the pressing plate 49 is articulated on the lower supporting plate 3 , and the lower part of the pressing plate 49 abuts against a pressing cam 50 driven by a groove-cutting pressure motor 26 .
A stereoscopic luminous character edge is enclosed with the invention as follows: a stainless steel band stretches out of the plate outlet of the raw material rotary disc 41 and is driven to move forward by the driving rollers 43 after passing through the guide wheel groups 42 , the grooving unit is started when the stainless steel band arrives at the grooving unit (the groove-cutting unit is not started temporarily because raw material is a stainless steel band), and the cylinder 16 is inflated simultaneously so that the piston of the cylinder 16 butts the back plate; because the pressure plates 15 and the cylinder 16 are mounted on both side of the back plate 14 and fixed by guide bolts 18 , the pop springs 17 between the pressure plates 15 and the back plate 14 are pressed whereby the stainless steel plate is held tightly by the pressure plates 15 and the back plate 14 , the tool holder 13 moves downward dynamically driven by the grooving driving device, and the grooving tool 56 mounted on the tool holder 13 can groove the stainless steel band. The stainless steel band is grooved for many times (generally twice) due to high hardness. After the grooving driving device drives the tool holder 13 to groove downward, the main motor 4 rotates reversely to drive the tool holder 13 to move upward when arriving at a certain position, in order to prevent the grooving tool 56 from touching the stainless steel band to cause scratches or non-collinear grooving lines when the tool holder 13 moves upward. The grooving tool 56 is fixedly mounted on a grooving tool fixing plate 57 , the upper end of the grooving tool fixing plate 57 is articulated on the tool holder 13 , the rear end of the grooving tool 56 extends into the tool holder 13 , and the grooving tool 56 and the grooving tool fixing plate 57 can rotate away from the stainless steel plate along the hinge shaft thereof, such that the tool holder 13 can not touch the stainless steel plate when moving upward. When the tool holder 13 moves up to a certain height, the main motor 4 rotates reversely again to drive the tool holder 13 to move downward for second grooving, the adjusting cylinder 21 is started simultaneously, the vertical plate 11 is fixedly mounted between the upper supporting plate and the lower supporting plate such that the piston of the adjusting cylinder 21 butts the adjusting plate 20 , the adjusting plate 20 moves forward a distance along the lower supporting plate 3 to adjust the amount of feed of the tool holder 13 whereby the grooving depth of the stainless steel band is increased to meet the requirement of edge bending (the adjusting plate moves forward a minimal distance, so that it can not affect the transmission connection between the gear 5 and the rack 6 ). Because the guide pin 22 passing through the adjusting plate 20 and the vertical plate 11 is provided, and the rubber spring 53 is arranged on the guide pin 22 positioned on the inner vertical surface of the adjusting plate 20 , the adjusting plate 20 moves forward a distance and can ensure the parallelism between the adjusting plate and the vertical plate 11 , so that the two grooving operations can be at the same grooving line. The rubber spring 53 plays a role of restoring the adjusting cylinder 21 after adjusting the feed of the grooving tool, and simultaneously the rubber spring 53 springs the adjusting plate 20 back to the original position such that grooving can be carried out at another position of the stainless steel character edge band. Arc curving is then carried out at a specified position of the stainless steel band with the arc-curving unit, and finally, the stainless steel character edge is cut by the shearing unit to complete the molding of the whole character edge.
Groove-cutting process of a plate is carried out as follows: an aluminum strip stretches out of the plate-stretch opening of the raw material rotary disc 41 and is driven to move forward by the driving rollers 43 after passing through the guide wheel groups 42 . When the plate moves to the groove-cutting unit and needs to be cut, the groove-cutting pressure motor 26 is started to drive the pressing cam 50 to rotate a certain angle to push the lower end of the pressing plate 49 a distance, and because the middle part of the pressing plate 49 is articulated on the lower supporting plate 3 , the upper part of the pressing plate 49 presses the two rotating pressure feet 46 , and the two rotating pressure feet 46 come close to the support connection plate 45 such that a plate passage becomes narrower to tightly hold the plate. The cutting motor 39 is started simultaneously to drive the cutting tool holder 40 to rotate, and the elevating motor 33 is started whereby the transmission belt 34 drives the cutting tool holder 40 to move downward and cut the plate; when the plate needs to be grooved on both sides, the upper supporting plate 2 is provided with cut grooves 10 , and after the elevating motor 33 drives the cutting tool holder 40 to a certain height, the rotating motor 37 is started to drive the cutting tool holder into the cut groove 10 to cut the other side of the plate, and because the cutting surface of the cutting tool holder 40 and the axial line of the power output shaft of the rotating motor 37 are in the same plane, the two cut grooves can be ensured to be on the both sides of the same position when the cutting blade mounted on the cutting tool holder 40 cut both sides of the plate. The rotating motor 37 can freely rotate at any angle under electric control to carry out grooving of different depths and directions, thereby meeting the grooving requirements of different character edge plates.
The operations of arc curving and cutting of a character edge band are realized with the arc-curving unit and the cutting unit as follows: a character edge hand plate enters arc-curving sleeves 24 from the guide plates 23 , the side walls of the arc-curving sleeves 24 at the plate outlet are longitudinally and evenly provided with press-curving rolling balls 55 , when a control program controls a servo motor 25 to rotate at a certain angle according to the requirement of a character, the arc-curving sleeves 24 rotate accordingly, and because the guide rollers 9 in the arc-curving sleeve 24 are fixed, the press-curving rolling balls 54 press the plate and bend the plate to a certain angle, and the rotation of the press-curving rolling balls 54 can eliminate sliding friction between the press-curving rolling balls and the plate during arc curving. After the arc curving is completed, the shearing motor 31 is started to drive the two transmission racks 30 to move in the same direction such that the inner cylinder 12 and the outer cylinder 27 rotate in opposite directions, the cutting edges 28 of the inner cylinder 12 and the outer cylinder 27 interact on each other to cut the character edge band to finish the molding of the character edge band.
In the invention, all motors and grooving driving devices such as the cylinder 16 are operated and controlled by an electric control cabinet 19 through electric control, and because the control principles and processes are well know in the prior art, there is no need to go into details here. | A luminous character enclosing machine has an upper supporting plate ( 2 ) and a lower supporting plate ( 3 ) which are installed on a machine frame ( 1 ). A plate inlet and a plate outlet are formed respectively on two ends of the upper and lower supporting plates. A feeding unit, a grooving unit, an arc-curving unit, and a plate-clamping unit arranged between the two supporting plates are provided in succession from the plate inlet to the plate outlet. A grooving driving device is installed on the machine frame, and drives the grooving device to move up and down. This kind of grooving mode is a cold processing mode, heat generation during working which makes color of the stainless steel plates change is avoided, and a phenomenon of knife broken due to high speed rotation of a saw blade and the hardness of the stainless steel is prevented. The machine is simple in structure and convenient to operate. | 1 |
This is a continuation application of U.S. patent application Ser. No. 08/859,185, filed Jun. 20, 1997, the disclosure of which is incorporated by reference.
BACKGROUND TO THE ART
The current means of combating migraine attacks include simple analgesics such as aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDS) and paracetamol, taken at the earliest signs of an attack [1,2,3]. Aspirin, paracetamol and phenacetin have long been among the most commonly used members of the NSAIDS class. Amongst the newer NSAIDS are ibuprofen, ketoprofen, mefenamic acid, diflunisal, naproxen and piroxicam. The most widely used NSAIDS available over the counter that have fewer gastro intestinal side effects than aspirin are paracetamol and ibuprofen.
Combined preparations of paracetamol or aspirin with an anti-emetic agent such as buclizine or metoclopramide, have been used to alleviate the nausea symptoms that often accompanied a migraine attack. Commercially, they are available as Migraleve Duo®, Paramax®, Migravess®. Narcotic analgesics such as codeine have also been employed together with NSAIDS to obtain synergistic analgesia, for example Migraleve Yellow®, co-codamol.
Gastric stasis, commonly present in migraine[4], causes the poor absorption of the analgesics. Dispersible and effervescent formulations have been used in an attempt to overcome this [4]. Metoclopramide, an anti-emetic, also relieves gastric stasis which has been found useful counteracting the reduced analgesic effects of paracetamol in migraine attacks [1,4,5].
Attacks who do not respond to analgesics may be treated with ergot preparations such as ergotamine tartrate. Newer alternatives to ergot compounds for acute migraine are the selective serotonin 5HT1 agonist, for example Sumatriptan® [6,7]. Recent trials reported that oral 100 mg sumatriptan to be as effective as aspirin 900 mg plus 10 mg metoclopramide for initial attacks and more effective in subsequent attacks [8].
The use of metoclopramide combined with either paracetamol, or aspirin has already been disclosed. Domperidone is a dopamine antagonist but is less likely than metoclopramide to produce extra pyramidal side effects since it does not cross the blood brain barrier. It stimulates gastro-intestinal mobility and is used in the management of nausea and vomiting. The activity of domperidone on the gastro intestinal mobility could enhance the rate of absorption of the analgesics. In Cephalagia 13 (2), 124-7 (1993), the safety and efficacy of separately administered domperidone in combination with paracetamol in the treatment of acute attack of migraine was demonstrated. The method of making a film coated tablet containing paracetamol and domperidone is disclosed in WO95/22974.
As far as the inventor knows, the art has never suggested that domperidone either be added to selected NSAIDS, which differ substantially in chemical structure from paracetamol; or be added to selected NSAIDS together with selected narcotic analgesic drugs. Also, the prior art does not suggest the use of any two-component composition of a selected NSAID and domperidone; and three-component of a selected NSAID, a selected narcotic analgesic and domperidone to hasten the analgesic response and to manage nausea symptoms in migraine attacks.
DETAILED DESCRIPTION OF THE INVENTION
The NSAIDS for use in the compositions and methods of the present invention can be selected from the following categories:
1) the propionic acid derivatives
2) the acetic acid derivatives;
3) the fenamic acid derivatives;
4) the biphenylcaboxylic acid derivatives;
5) the oxicams.
All the contemplated compounds can be used at appropriate dosage levels for the purpose in the composition of the present invention. The compounds in groups 1 to 4 typically contain a carboxylic acid function; however, those acids are sometimes administered in the form of their pharmaceutically acceptable salts, e.g. sodium salts.
The propionic acid derivatives for use herein include, but are not limited to, ibuprofen, naproxen, benoxaprofen, flurbiprofen, fenoprofen, fenbufen, ketoprofen, indoprofen, pirprofen, carprofen, oxaprozin, prapoprofen, miroprofen, tioxaprofen, suprofen, alminoprofen, tiaprofenic acid, fluprofen, and bucloxic acid. Structurally related propionic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group. Presently preferred members of the propionic acid group include ibuprofen, naproxen, flurbiprofen, fenoprofen, ketoprofen and fenbufen.
The acetic acid derivatives for use herein include, but not limited to, indomethacin, sulindac, tolmetin, zomepirac, diclofenac, fenchlofenac, alchlofenac, ibufenac, isoxepac, furofenac, tiopinac, zidometacin, acemetacin, fentiazac, clidanac and oxipinac. Structurally related acetic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group. Presently, preferred members of the acetic acid group include tolmetin sodium, zomepinac sodium, sulindac and indomethacin.
The fenamic acid derivatives for use herein include, but are not limited to, mefenamic acid, meclofenamic acid, flufenamic acid, niflumic acid and tolfenamic acid. Structurally related fenamic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to encompassed by this group. Presently, preferred members of the fenamic acid group include mefenamic acid and meclofenamate sodium (meclofenamic acid, sodium salt).
The biphenylcarboxylic acid derivatives for use herein include, but are not limited to, diflunisal and flufenisal. Structurally related biphenylcarboxylic acid derivatives having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group. Preferred members of this group are diflunisal and flufenisal.
The oxicams for use herein include, but are not limited to, piroxicam, sudoxicam, isoxicam. Structurally related oxicams having similar analgesic and anti-inflammatory properties are also intended to be encompassed by this group. A preferred member of this group is piroxicam.
The narcotic analgesics for use in the present invention are orally active narcotic agonists. Suitable agonist-antagonist for use herein include orally analgesically active antagonists of the nalorphine type, notably pentazocine; and orally analgesically active antagonists of the morphine type, notably buprenorphine. Another suitable agonist-antagonist is meptazinol. Suitable narcotic agonists for use herein include orally analgesically active members of the morphine group, notably codeine, oxycodone, dihydrocodeine, dextropropoxyphene, papaveretum and tramadol. In many instances, the narcotic analgesics for use herein are administered in the forms of their pharmaceutically acceptable acid addition salts, e.g. codeine sulphate, codeine phosphate, dihydrocodeine tartrate and tramadol hydrochloride. Structurally related analogues to the aforementioned compounds having similar analgesic property are also intended to be encompassed by this group.
For compounds (NSAIDS or narcotic analgesics) which have optically active centre(s), the invention refers to the racemate as well as the pure (−) or (+) optical isomeric forms.
The domperidone or its analogues used herein is intended to encompass not only domperidone as the anhydrous powder but any salt or derivatives or any compounded mixture thereof which is non toxic, pharmaceutically acceptable and which has gastric motility stimulating activity to enhance absorption of the co-administered analgesic(s) in gastric stasis and anti-emetic property. Presently, the preferred salt of domperidone is maleate.
The term “selected NSAID” as used herein is intended to mean any non-narcotic analgesic/nonsteroidal anti-inflammatory compound within one of the five structural categories indicated hereinabove. Similarly, the term “selected narcotic analgesic” as used herein is intended to mean any orally analgesically active narcotic analgesic, be it an orally active narcotic agonist having oral analgesic activity. The terms “selected NSAID” and “selected narcotic analgesic” are used for the sake of simplicity in the discussion which follows.
When a selected NSAID or NSAID plus a selected narcotic analgesic is combined with domperidone in accord with the present invention, the following results may be produced:
The analgesic/anti-inflammatory effect of the selected NSAID as a single active or NSAID plus a selected narcotic analgesic can be brought on more quickly;
the nausea symptom experienced in acute migraine attacks can be averted or alleviated.
For patients suffering migraine headache, the time from administration of medication to the onset of effective relief is clearly of paramount importance. The hastening of the onset analgesia by combining domperidone with a selected NSAID or a selected NSAID plus a selected narcotic analgesic according to the present invention is therefore can be very significant.
The precise amount of NSAID or narcotic analgesic drug for use in the present compositions will vary depending, for example, on the specific drug chosen, the condition for which the drug is administered. Generally speaking, the selected NSAID or narcotic analgesic can be employed in any amount known to be an effective analgesic and anti-inflammatory amount.
Typical effective analgesic amounts of presently preferred NSAIDs/narcotic analgesic for use in unit dose compositions of the invention can be found in the British National Formulary, American Hospital Formulary, Martindale Extra Pharmacopoeia, e.g. 50-600 mg Ibuprofen. In a two component composition of a selected NSAID and domperidone and a three component composition of a selected NSAID, a selected narcotic analgesic and domperidone, the daily analgesic dose for each analgesic will generally not exceed their daily analgesic dosages. The ratio of a selected NSAID to a selected narcotic analgesic may vary depending on the particular drugs selected and the required analgesic response.
While the compositions of the invention are preferably for oral use, they may also be formulated for and administered by other methods which are known for administering analgesics, e.g. suppositories. Also, the preferred dosage levels mentioned earlier are used in adults; paediatric compositions would contain proportionally less of the active ingredients.
The compositions of the present invention can be conveniently administered by any route of administration suitable for the selected NSAID and/or selected narcotic analgesic component, e.g. oral or rectal. Preferably, the combination is formulated with any suitable nontoxic pharmaceutically acceptable inert carrier material. Such carrier materials are well known to those skilled in the art.
In a typical preparation for oral administration, e.g. tablet or capsule, the selected NSAID in an effective analgesic/anti-inflammatory amount and domperidone in an amount sufficient to hasten its onset and/or to control nausea and vomiting; or the selective NSAlD in an effective analgesic/anti-inflammatory amount together with a selected narcotic analgesic in an amount sufficient to enhance the analgesic response and domperidone in an amount sufficient to hasten its onset and/or to control nausea and vomiting; are combined with any oral nontoxic pharmaceutically acceptable inert carrier such as lactose, starch (pharmaceutical grade), dicalcium phosphate, calcium sulphate, kaolin, mannitol and powder sugar.
Additionally, when required, suitable binders, lubricants, disintegrating agents, colouring agents and coating agents can also be included. Typical binders include starch, gelatine, sugars such as sucrose, molasses and lactose, natural and synthetic gums such as acacia, sodium alginate, carboxymethylcellulose, methylcellulose, polyvinylpyrrolidone, polyethylene glycol, ethylcellulose and waxes. Typical lubricants for use in the dosage forms can include, without limitation, boric acid, sodium benzoate, sodium acetate, sodium chloride, leucine and polyethylene glycol. Suitable disintegrators can include, without limitation, starch, methylcellulose, agar, bentonite, cellulose, wood products, alginic acid, guar gum, citris pulp, carboxymethylcellulose and sodium lauryl sulphate. Sweetening and flavouring agents and preservatives may be included, particularly when a liquid dosage form is formulated, e.g. syrup, suspension and elixir. When the dosage form is a capsule, it may contain, in addition to the above type, a liquid carrier such as fatty oil. Various other materials may be present as coatings or to otherwise modify the physical form of the dosage unit.
REFERENCES
1) Atkinson R, Appenzeller O (1984). Headache. Postgrad Med J; 60: 841-846.
2) Diamond S, Milistein E (1988). Current concepts of migraine therapy. J. Clin Pharmacol; 28: 193-199.
3) Anonymous (1984). Drugs for migraine. Med Lett Drugs Ther; 26: 95-96.
4) Clough C (1989). Treating migraine. Br Med J; 299: 141-142.
5) Peatfield R (1983). Migraine: Current concepts of pathogenesis and treatment. Drugs; 26: 364-371.
6) Pearce JMS (1991). Sumatriptan in migraine. Br Med J; 303: 1941.
7) Fullerton T, Gengo F M (1992). Sumatriptan: a selective 5-hydroxytryptamine receptor agonist for the acute treatment of migraine. Ann Pharmacother; 26: 800-808.
8) The oral Sumatriptan and Aspirin plus Metoclopramide Comparative Study Group (1992). A study to compare oral sumatriptan with oral Aspirin plus oral metoclopramide in the acute treatment of migraine. Eur Neurol; 32:177-184. | The present invention provides a method for eliciting an onset hastened analgesic and anti-inflammatory response and combating nausea in acute migraine attacks. This method comprises administering a pharmaceutical composition comprising more than one active ingredient, wherein said more than one active ingredient consist essentially of:
(i) domperidone or an analogue thereof in an amount sufficient to hasten the onset of the analgesic and anti-inflammatory response and to combat nausea in an acute migraine attack, and
(ii) a NSAID, a pharmaceutically acceptable salt thereof or a pure (−) or pure (+) optical isomeric form thereof in an analgesically and anti-inflammatory effective amount, wherein said NSAID is selected from the group consisting of proprionic acid derivatives, acetic acid derivatives, fenamic acid derivatives, biphenylcarboxylic acid derivatives and oxicams. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 USC 119 (a)-(d) to Korea Application No. 10-2008-0119772 filed on Nov. 28, 2008, the contents of which are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
The present invention relates to a TRPA1 activity inhibitor, more precisely isopentenyl pyrophosphate, a compound for suppressing TRPA1 mediated pain by inhibiting TRPA1 activity and a novel use of the same.
TRPA1 (transient receptor potential cation channel, subfamily A, member 1) was first found in 2003 owing to the studies in the fields of human physiology and pharmacology. TRPA1 is activated as it recognizes diverse stimuli such as low temperature stimulus, inflammatory stimulus, and mechanical stimulus, etc. And by the activation of TRPA1, the human body feels pain. TRPA1 belongs to thermoTRP family (temperature-sensitive transient receptor potential ion channels) that is the pain receptor family recognizing temperature and painful stimuli. Researches expect that human pain recognition mechanism can be explained by disclosing functions of TRPA1, the pain receptor, and additionally the pursuing goal of pain relief can be achieved by the development of a TRPA1 regulator.
There is no report on an endogenous pain inhibitor, yet. Studies have been actively going on different types of pain, but mechanisms of pain regulators in vivo have not been disclosed yet. Prostaglandin generated by inflammation and its metabolites and aldehydes are known as pain inducing materials.
To understand basic techniques used for the development of a pain inhibitor based on the TRPA1 specific inhibitor, it is important to understand the characteristics of TRPA1. TRPA1 is an ion channel and its activation makes cations migrate into sensory neurons, changing of cell membrane currents. The changes of cell membrane currents result in the generation of active potential, which is at last transferred to the brain to recognize pain. One of the techniques to measure TRPA1 activation is patch-clamp electrophysiological technique measuring the changes of membrane currents after amplifying thereof. And another technique to measure TRPA1 activation is to measure intracellular calcium level based on the fact that TRPA1 is involved in the migration of cations such as calcium ions. The first technique is superior in sensitivity to the second one, but the second technique is superior in high speed to the first one, so that they are complementary to each other. Such techniques to measure TRPA1 activation can be executed by the support of animal neuron culture technique, cell line culture technique, TRPA1 DNA control and transfection techniques. Various TRPA1 specific inhibitor candidates and a standard activator are administered to TRPA1 over-expressing cells and then inhibiting effect of TRPA1 activation therein is measured to select a proper TRPA1 inhibitor and determine its capacity.
The present inventors constructed a cell line expressing TRPA1 and treated the cell line with isopentenyl pyrophosphate and cinnamaldehyde known as a TRPA1 activator. Then, responses therein were compared. At last the present inventors completed this invention by confirming that isopentenyl pyrophosphate inhibited TRPA1 activity and thus it could be effectively used as an inhibitor of TRPA1 mediated pain.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method for inhibiting TRPA1 (transient receptor potential cation channel, subfamily A, member 1) activity using isopentenyl pyrophosphate.
It is another object of the present invention to provide a method for screening a TRPA1 activity inhibitor using isopentenyl pyrophosphate.
It is also an object of the present invention to provide a method for inhibiting pain of a subject using isopentenyl pyrophosphate.
To achieve the above objects, the present invention provides a method for inhibiting TRPA1 (transient receptor potential cation channel, subfamily A, member 1) activity using isopentenyl pyrophosphate.
The present invention also provides a method for screening a TRPA1 activity inhibitor comprising the following steps;
1) constructing a transformant by transfecting a host cell with a plasmid harboring the polynucleotide encoding TRPA1;
2) treating the transformant with TRPA1 specific activator and TRPA1 activity inhibitor candidates as the experimental group, and treating the transformant with TRPA1 specific activator and isopentenyl pyrophosphate as the control;
3) measuring TRPA1 ion channel activities in the experimental group and in the control group of step 2); and
4) comparing the results of step 3) and selecting TRPA1 activity inhibitor candidates from the experimental group that demonstrated lower or similar TRPA1 ion channel activity, compared with the control.
The present invention further provides a method for inhibiting pain containing the step of administering a pharmaceutically effective dose of isopentenyl pyrophosphate to a subject.
Isopentenyl pyrophosphate of the present invention can regulate pain caused by TRPA1, so that it can be effectively used for the development of a pain inhibitor which is effective but has less side effects.
BRIEF DESCRIPTION OF THE DRAWINGS
The application of the preferred embodiments of the present invention is best understood with reference to the accompanying drawings, wherein:
FIG. 1 is a diagram illustrating that TRPA1 specific activity induced by cinnamaldehyde in mTRPA1 cell line was inhibited by isopentenyl pyrophosphate (CA: cinnamaldehyde).
FIG. 2 is a diagram illustrating that TRPA1 activity was specifically inhibited by isopentenyl pyrophosphate in mTRPA1 cell line dose-dependently.
FIG. 3 is a diagram illustrating that pain induced by cinnamaldehyde under normal or inflammatory condition was inhibited by isopentenyl pyrophosphate (CAR: carrageenan, CFA: complete Freund's adjuvant):
a: 100 μM of isopentenyl pyrophosphate and 300 μM CA; b: 300 μM of CA and 300 μM of CA+100 μM of isopentenyl pyrophosphate; c: 50 μl of CAR+300 μM of CA+100 μM of isopentenyl pyrophosphate and 10 μl of CFA+300 μM of CA+100 μM of isopentenyl pyrophosphate; and, d: histogram illustrating the results of 10-minute reaction in FIG. 3 a - FIG. 3 c (The time required was statistically calculated by T-test, for which CA alone was regarded as standard).
FIG. 4 is a diagram illustrating the changes of avoidance time from temperature stimulus by isopentenyl pyrophosphate under inflammatory condition:
Control: carrageenan not treated group CAR: carrageenan treated group CAR+IPP: carrageenan and isopentenyl pyrophosphate treated group CAR+AP18: carrageenan and AP18 treated group.
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention is described in detail.
The present invention provides a method for inhibiting TRPA1 activity containing the step of treating isopentenyl pyrophosphate to isolated sensory neurons expressing TRPA1.
In a preferred embodiment of the present invention, it was confirmed that TRPA1 activity induced by cinnamaldehyde known as a TRPA1 specific activator was inhibited by isopentenyl pyrophosphate dose-dependently (see FIGS. 1 and 2 ). It was also confirmed that isopentenyl pyrophosphate inhibited TRPA1 mediated pain (see FIG. 3 ). Therefore, the said isopentenyl pyrophosphate can be effectively used for inhibiting TRPV3 activity.
The preferable concentration of isopentenyl pyrophosphate was 10-100 μM. In a preferred embodiment of the present invention, the TRPA1 inhibitor was confirmed to inhibit TRPA1 activity at micro-molar concentration range (see FIG. 2 ).
Isopentenyl pyrophosphate of the present invention can be formulated for oral administration, for example powders, granules, tablets, capsules, suspensions, emulsions, syrups and aerosols, and for parenteral administration, for example external use, suppositories and sterile injections, etc.
Solid formulations for oral administration are powders, granules, tablets, capsules, soft capsules and pills. Liquid formulations for oral administration are suspensions, solutions, emulsions and syrups, and the above-mentioned formulations can contain various excipients such as wetting agents, sweeteners, aromatics and preservatives in addition to generally used simple diluents such as water and liquid paraffin. For formulations for parenteral administration, powders, granules, tablets, capsules, sterilized suspensions, liquids, water-insoluble excipients, suspensions, emulsions, syrups, suppositories, external use such as aerosols and sterilized injections can be prepared by the conventional method, and preferably skin external pharmaceutical compositions such as creams, gels, patches, sprays, ointments, plasters, lotions, liniments, pastes or cataplasms can be prepared, but not always limited thereto. Water insoluble excipients and suspensions can contain, in addition to the active compound or compounds, propylene glycol, polyethylene glycol, vegetable oil like olive oil, injectable ester like ethylolate, etc. Suppositories can contain, in addition to the active compound or compounds, witepsol, macrogol, tween 61, cacao butter, laurin butter, glycerogelatin, etc.
The present invention also provides a method for screening a TRPA1 activity inhibitor comprising the following steps:
1) constructing a transformant by transfecting a host cell with a plasmid harboring the polynucleotide encoding TRPA1;
2) treating the transformant with TRPA1 specific activator and TRPA1 activity inhibitor candidates as the experimental group, and treating the transformant with TRPA1 specific activator and isopentenyl pyrophosphate as the control;
3) measuring TRPA1 ion channel activities in the experimental group and in the control group of step 2); and
4) comparing the results of step 3) and selecting TRPA1 activity inhibitor candidates from the experimental group that demonstrated lower or similar TRPA1 ion channel activity, compared with the control.
In a preferred embodiment of the present invention, it was confirmed that TRPA1 activity induced by cinnamaldehyde known as a TRPA1 specific activator was inhibited by isopentenyl pyrophosphate dose-dependently (see FIGS. 1 and 2 ). It was also confirmed that isopentenyl pyrophosphate was inhibited TRPA1 mediated pain in animal models (see FIG. 3 ). Therefore, the said isopentenyl pyrophosphate can be effectively used for the screening of a TRPA1 activity inhibitor.
The host cell herein is preferably any cell line that can be used for the study of calcium channel activity and high throughput screening, for example HEK, CHO, HeLa, and RBL-2H3, but not always limited thereto.
The TRPA1 specific activator of step 2) is cinnamaldehyde or acetaldehyde.
The measuring of ion channel activity of step 3) can be performed by whole cell voltage clamp technique or calcium imaging.
The preferable concentration of isopentenyl pyrophosphate is 0.1-100 μM.
The preferable concentration of isopentenyl pyrophosphate is 10-100 μM. In a preferred embodiment of the present invention, the TRPA1 inhibitor was confirmed to inhibit TRPA1 activity at micro-molar concentration range (see FIG. 2 ).
The present invention also provides a method for inhibiting pain containing the step of administering a pharmaceutically effective dose of isopentenyl pyrophosphate to a subject.
In a preferred embodiment of the present invention, it was confirmed that isopentenyl pyrophosphate inhibited TRPA1 mediated pain in animal models (see FIG. 3 and FIG. 4 ). So, the said isopentenyl pyrophosphate can be effectively used as a composition for inhibiting pain.
The pain herein is mediated by TRPA1 activity.
The subject herein is one of vertebrates and preferably mammals and more preferably selected from such test animals as rats, rabbits, guinea pigs, hamsters, dogs and cats, and most preferably apes such as chimpanzees and gorillas. The composition of the present invention can be administered orally or parenterally. For example the possible administration pathway can be oral administration, rectal administration, intravenous injection, intramuscular injection, hypodermic injection, intrauterine injection or intracerebroventricular injection. The composition for inhibiting pain of the present invention can be administered alone or treated together with surgical operation, hormone therapy, chemo-therapy and biological regulators.
The effective dosage of the composition of the present invention can be determined by those in the art according to condition and weight of a patient, severity of a disease, type of a drug, administration pathway and duration. Preferably, the composition of the present invention can be administered by 0.0001-100 mg/kg per day, and more preferably by 0.001-100 mg/kg per day. The administration frequency is once a day or a few times a day.
The composition for inhibiting pain can include, in addition to isopentenyl pyrophosphate, one or more effective ingredients having the same or similar function to isopentenyl pyrophosphate. The composition of the present invention preferably includes isopentenyl pyrophosphate by 0.0001-10 weight % and more preferably 0.001-1 weight % for the total weight of the composition.
The composition of the present invention can additionally include generally used carriers, excipients, disintegrating agents, sweetening agents, lubricants, flavors and diluents. The carriers, excipients and diluents are exemplified by lactose, dextrose, sucrose, sorbitol, mannitol, xylitol, erythritol, maltitol, starch, acacia rubber, alginate, gelatin, calcium phosphate, calcium silicate, cellulose, methyl cellulose, microcrystalline cellulose, polyvinyl pyrrolidone, water, methylhydroxybenzoate, propylhydroxybenzoate, talc, magnesium stearate and mineral oil. The disintegrating agent is exemplified by sodium carboxy methyl starch, crospovidone, croscarmellose sodium, alginic acid, calcium carboxymethyl cellulose, sodium carboxymethyl cellulose, chitosan, guar gum, low-substituted hydroxypropyl cellulose, magnesium aluminum silicate, polacrilin potassium, etc.
The composition for inhibiting pain of the present invention can be provided as a pharmaceutical composition. The pharmaceutical composition of the present invention can additionally include a pharmaceutically acceptable additive, which is exemplified by starch, gelatinized starch, microcrystalline cellulose, lactose, povidone, colloidal silicon dioxide, calcium hydrogen phosphate, lactose, mannitol, taffy, Arabia rubber, pregelatinized starch, corn starch, cellulose powder, hydroxypropyl cellulose, Opadry, sodium carboxy methyl starch, carunauba wax, synthetic aluminum silicate, stearic acid, magnesium stearate, aluminum stearate, calcium stearate, white sugar, dextrose, sorbitol, talc, etc. The pharmaceutically acceptable additive herein is preferably added by 0.1-90 weight part to the pharmaceutical composition.
The composition for inhibiting pain of the present invention can be provided as a composition for health food.
Isopentenyl pyrophosphate of the present invention can be used as food additive. In that case, isopentenyl pyrophosphate can be added as it is or as mixed with other food components according to the conventional method. The mixing ratio of active ingredients can be regulated according to the purpose of use (prevention or health enhancement). In general, to produce health food or beverages, isopentenyl pyrophosphate is added preferably by 0.2-20 weight % and more preferably by 0.24-10 weight %. However, if long term administration is required for health and hygiene or regulating health condition, the content can be lower than the above but higher content can be accepted as well since isopentenyl pyrophosphate has been proved to be very safe.
The health food of the present invention can additionally include various flavors or natural carbohydrates, etc, like other beverages. The natural carbohydrates above can be one of monosaccharides such as glucose and fructose, disaccharides such as maltose and sucrose, polysaccharides such as dextrin and cyclodextrin, and glucose alcohols such as xilytole, sorbitol and erythritol. Besides, natural sweetening agents such as thaumatin and stevia extract, and synthetic sweetening agents such as saccharin and aspartame can be included as a sweetening agent. The content of the natural carbohydrate is preferably 0.01-0.04 weight part and more preferably 0.02-0.03 weight part in 100 weight part of the health food of the present invention.
The food herein is not limited. For example, isopentenyl pyrophosphate of the present invention can be added to meat, sausages, bread, chocolates, candies, snacks, cookies, pizza, ramyuns, flour products, gums, dairy products including ice cream, soups, beverages, tea, drinks, alcohol drinks and vitamin complex, etc, and in wide sense, almost every food applicable in the production of health food can be included.
In addition to the ingredients mentioned above, the health food of the present invention can include in variety of nutrients, vitamins, minerals, flavors, coloring agents, pectic acid and its salts, alginic acid and its salts, organic acid, protective colloidal viscosifiers, pH regulators, stabilizers, antiseptics, glycerin, alcohols, carbonators which used to be added to soda, etc. The health food of the present invention can also include natural fruit juice, fruit beverages and/or fruit flesh addable to vegetable beverages. All the mentioned ingredients can be added singly or together. The mixing ratio of those ingredients does not matter in fact, but in general, each can be added by 001-0.1 weight part per 100 weight part of the health food of the present invention.
Practical and presently preferred embodiments of the present invention are illustrative as shown in the following Examples, Experimental Examples and Manufacturing Examples.
However, it will be appreciated that those skilled in the art, on consideration of this disclosure, may make modifications and improvements within the spirit and scope of the present invention.
Example 1
Construction of Cell Lines Transfected with TRPA
HEK293T cell line (ATCC CRL-11268) was transiently transfected with plasmid DNA containing polynucleotide encoding rTRPA1 (SEQ. ID. NO: 1).
Particularly, the HEK293T cell line was transiently transfected with 3 μg/35 mm dish of pcDNA5/FRT vector containing polynucleotide encoding mTRPA1, and 600 ng/well of pCDNA3 (Invitrogen Corp., USA; containing green fluorescent protein (GFP) cDNA) using Fugene6 (Roche Diagnostics, USA) according to manufacturer's instruction. The transformed cells were cultured in DMEM/F12 medium containing 10% FBS and 1% penicillin/streptomycin in a CO 2 incubator for 24 hours. The cells were smeared on poly-L-lysine-coated glass coverslips, followed by further culture for 10-24 hours.
Example 2
Statistical Treatment
All the results of examples were statistically analyzed by two-tailed, unpaired Student's-t-test and the results were presented by mean±S.E.M. (**p<0.01, and *p<0.05).
Example 3
TRPA1 Activity Inhibition by TRPA1 Inhibitor
<3-1> Treatment of Compounds
The mTRPA1 transfected cell line (n=73) prepared in Example 1 was treated with 300 μM of cinnamaldehyde (CA; MP Biomedicals, USA), during which 100 μM of isopentenyl pyrophosphate (Biomol, USA) was treated for a certain period of time. Stock solutions were made using water or ethanol, and were diluted with test solutions before use.
<3-2> Measurement of Intracellular Calcium Level Changes by Calcium Imaging
Calcium imaging was performed with the transfected cell line treated by the method of Example <3-1>.
Particularly, the transfected cell line of Example <3-1> was loaded with Fluo-3AM (5 μM; Sigma Aldrich, USA) in the bath solution (140 mM NaCl, 5 mM KCl, 2 mM CaCl 2 , 1 mM MgCl 2 , 10 mM HEPES; adjusted to pH 7.4 with NaOH) containing 0.02% pluronic acid (Invitrogen, USA) at 37° C. for 1 hour. Calcium imaging was performed with LSM5 Pascal confocal microscope (Carl Zeiss, Germany), and time-lapse images (excitation 488 nm/emission 514 nm) were collected every 3 seconds using Carl Zeiss ratio tool software (Carl Zeiss, Germany). Mean value curve of calcium influx responses was made by Hill plot.
As a result, as shown in FIG. 1 , TRPA1 activity induced by cinnamaldehyde was inhibited by isopentenyl pyrophosphate.
Example 4
TRPA1 Activity Over TRPA1 Inhibitor Concentration
The TRPA1 transfected cell line (n=73-127) prepared in Example 1 was treated with 300 μM of CA and 1, 10 and 100 μM of isopentenyl pyrophosphate. Calcium imaging was performed with the transfected cell line.
As a result, as shown in FIG. 2 , TRPA1 activity induced by cinnamaldehyde was inhibited by isopentenyl pyrophosphate in the mTRPA1 cell line dose-dependently.
Example 5
Pain Relieving Response by TRPA1 Inhibitor Examined by Animal Test
<5-1> Inducement of Inflammatory Sensitization
Inflammatory sensitization by isopentenyl pyrophosphate was investigated. Particularly, 50 μl of 1% carrageenan (CAR, Sigma Aldrich, USA) was injected to the right hind paws of mice 3 hours before the isopentenyl pyrophosphate injection or 10 μl of CFA (complete Freund's adjuvant; Sigma Aldrich, USA) was injected 24 hours before the isopentenyl pyrophosphate injection. At this time, 10 mM cinnamaldehyde was diluted in PBS containing 0.5% Tween 80 for injection. Before the experiment, the mice were adapted for one hour to the experimental environment. 10 μl of vehicle (saline containing 3% DMSO and 0.5% Tween 80) alone or 10 μl of vehicle containing isopentenyl pyrophosphate (3 mM) was injected to the right hind paws of the mice.
<5-2> Investigation of Acute Licking/Flicking Behaviors
The time spent for the hind paw licking/flicking behaviors in mice were measured according to the method of Bandell M, et al. ( Neuron 41:849-857, 2004) and Moqrich A, et al. ( Science 307:1468-1472, 2005), for 10 minutes.
Control: non-treatment; Experimental group 1. 100 μM of isopentenyl pyrophosphate; Experimental group 2. 300 μM of CA; Experimental group 3. 300 μM of CA+100 μM of isopentenyl pyrophosphate; Experimental group 4. 50 μl of CAR+300 μM of CA+100 μM of isopentenyl pyrophosphate; and, Experimental group 5. 10 μl of CFA+300 μM of CA+100 μM of isopentenyl pyrophosphate.
As a result, as shown in FIG. 3 , unlike isopentenyl pyrophosphate, cinnamaldehyde increased the time spent for the behaviors ( FIG. 3 a ), and co-treatment of cinnamaldehyde and isopentenyl pyrophosphate reduced the time spent for the behaviors ( FIG. 3 b ).
When carrageenan or CFA was injected to cause inflammation, the time spent for the behaviors which had been increased by cinnamaldehyde was also reduced by isopentenyl pyrophosphate ( FIG. 3 c ). The result of 10 minute-reaction induced in animals was also consistent with the result shown in FIG. 3 d.
In addition, when CAR and CFA alone were injected and when isopentenyl pyrophosphate alone was treated, the time spent for the behaviors was not increased (no data).
<5-3> Analysis of Sensitivity to Thermal Stimulation
To investigate inhibition of inflammatory sensitization induced by isopentenyl pyrophosphate, 10 μl of 0.1% carrageenan (CAR; Sigma Aldrich, USA) was injected into the right hind paws of mice three hours before the isopentenyl pyrophosphate injection. 10 μl of isopentenyl pyrophosphate was injected into the experimental group at the concentration of 1 mM. Equal amount of AP18 (Biomol, USA), the TRPA1 specific inhibitor, was injected into the positive control. Avoidance time was measured by using thermal stimulator (Ugo basile plant test, Italy). Each group was composed of 5 mice and beam injection was performed four times, which were averaged. As a result, as shown in FIG. 4 , the mice injected with carrageenan were more sensitive to thermal stimulation than the mice not-treated. In the meantime, the mice co-treated with carrageenan and isopentenyl pyrophosphate (IPP) of the present invention demonstrated significantly reduced sensitivity against thermal stimulation. Particularly, AP18 known as a TRPA1 specific inhibitor exhibited almost no effects. On the other hand, isopentenyl pyrophosphate of the present invention demonstrated significant effect, suggesting that it had excellent pain relieving effect, compared with the conventional TRPA1 inhibitors.
The Manufacturing Examples of the composition for the present invention are described hereinafter.
Manufacturing Example 1
Preparation of Pharmaceutical Formulations
<1-1> Preparation of Powders
Isopentenyl pyrophosphate 2 g Lactose 1 g
Powders were prepared by mixing all the above components, which were filled in airtight packs according to the conventional method for preparing powders.
<1-2> Preparation of Tablets
Isopentenyl pyrophosphate 100 mg Corn starch 100 mg Lactose 100 mg Magnesium stearate 2 mg
Tablets were prepared by mixing all the above components by the conventional method for preparing tablets.
<1-3> Preparation of Capsules
Isopentenyl pyrophosphate
100 mg
Corn starch
100 mg
Lactose
100 mg
Magnesium stearate
2 mg
Capsules were prepared by mixing all the above components, which were filled in gelatin capsules according to the conventional method for preparing capsules.
<1-4> Preparation of Pills
Isopentenyl pyrophosphate 1 g Lactose 1.5 g Glycerin 1 g Xylitol 0.5 g
Pills were prepared by mixing all the above components according to the conventional method for preparing pills. Each pill contained 4 g of the mixture.
<1-5> Preparation of Granules
Isopentenyl pyrophosphate
150 mg
Soybean extract
50 mg
Glucose
200 mg
Starch
600 mg
All the above components were mixed, to which 100 mg of 30% ethanol was added. The mixture was dried at 60° C. and the prepared granules were filled in packs.
Manufacturing Example 2
Preparation of Dairy Products
5˜10 weight part of isopentenyl pyrophosphate of the present invention was added to milk. Health enhancing dairy products such as butter and ice cream were prepared with the milk mixture according to the conventional method.
Manufacturing Example 3
Preparation of Beverages
<3-1> Preparation of Health Beverages
Isopentenyl pyrophosphate
1000
mg
Citric acid
1000
mg
Oligosaccharide
100
g
Maesil ( Prunus mume ) Extract
2
g
Taurine
1
g
Purified water
up to 900
Ml
The above constituents were mixed according to the conventional method for preparing health beverages. The mixture was heated at 85° C. for 1 hour with stirring and then filtered. The filtrate was loaded in 2 liter sterilized containers, which were sealed and sterilized again, stored in a refrigerator until they would be used for the preparation of a composition for health beverages. The constituents appropriate for favorite beverages were mixed according to the preferred mixing ratio but the composition ratio can be adjusted according to regional and national preferences, etc.
Those skilled in the art will appreciate that the conceptions and specific embodiments disclosed in the foregoing description may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present invention. Those skilled in the art will also appreciate that such equivalent embodiments do not depart from the spirit and scope of the invention as set forth in the appended Claims. | The present invention relates to a TRPA1 activation inhibitor, more precisely a TRPA1 activity inhibitor containing isopentenyl pyrophosphate and a method for inhibiting pain containing the step of administering isopentenyl pyrophosphate to a subject. Isopentenyl pyrophosphate of the present invention can regulate pain caused by TRPA1, so that it can be effectively used for the development of a pain inhibitor which is effective but has less side effects. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent application Ser. No. 14/065,708, filed on Oct. 29, 2013, which is a continuation of U.S. patent application Ser. No. 13/453,767, filed on Apr. 23, 2012 and issued as U.S. Pat. No. 8,571,286, which is a continuation of U.S. patent application Ser. No. 12/114,627, filed on May 2, 2008 and issued as U.S. Pat. No. 8,165,363, which claims priority to U.S. Provisional Patent App. No. 60/916,252, filed on May 4, 2007, all of which are hereby incorporated herein by reference in their entireties.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention generally relates to pathology and microscopy and more particularly relates to improvements in quality assurance for pathology using digital microscopy.
[0004] 2. Related Art
[0005] The diagnosis of glass microscope slides by a pathologist is known to be subjective. Many factors contribute to this lack of objectivity, including the training and skill of the pathologist and the quality of the glass slides from which the diagnosis was made. While use of tissue processing instruments and automatic staining equipment has increased the quality and consistency of slide preparations, a significant portion of glass slides that are read by pathologists are still suboptimal and may contribute to inaccurate interpretations.
[0006] One of the possible contributing factors to the subjectivity of reading pathology slides is the lack of standardization of the microscope, a tool that has been in use for hundreds of years and which is not recognized as an approved medical device. Pathologists are free to use whatever microscope they want to read glass slides and are expected to know how to keep their microscope in optimal (Koehler) alignment, what objectives lenses with what numerical apertures are best suited for different specimen types, and to be aware when the bulb in their microscope needs to be replaced (because the color temperature of the illuminating light will change the color in the image they observe through the microscope). Many pathologists' microscopes are not maintained in optimal working condition or furnished with optimal objective lenses, thus compromising spatial details and color fidelity that may be essential to making more accurate diagnoses.
[0007] Another likely contributing factor to the subjectivity of pathology is deficiencies in glass slide quality, which can include over- or under-staining (i.e., too dark or too light), tissue folds, sections that are too thick or too thin, bubbles, debris as well as variations in image quality observed between slides prepared by different autostainers. There is little a pathologist can do to overcome the challenges of a poorly prepared glass slides (“garbage in/garbage out”), other than to try to make adjustments in the optical properties of the microscope (adjust condenser, increase/decrease light) to try and ameliorate glass slide quality problems.
[0008] Referring to FIG. 1 , a flow diagram illustrating a conventional process for quality assurance using glass slides is shown. Initially, in step 100 a glass slide is prepared and then in step 110 the quality of the slide is inspected and assessed. In a typical laboratory, a histotechnologist screens the glass slides to assess slide quality, as shown in step 120 , and rejects sub-optimal slides before they are read by a pathologist. Rejected slides result in re-cuts and the preparation of new, presumably higher quality, glass slides. In some cases, the slides can be fixed, e.g., by restaining if the staining is too light. This is shown in step 130 . Finally, when a glass slide is acceptable, the slide is reviewed and interpreted by a pathologist in step 140 .
[0009] This conventional process suffers from the inability of the histotechnologist to carefully review every area of a glass slide (some labs process hundreds or thousands of slides every day). The conventional process additionally suffers from the increasing shortage of qualified histotechnologists, and pressure on laboratories to continually improve productivity. Furthermore, the overall aging of the population and the associated increased incidence of cancer (and surgical biopsies) only exacerbate the challenges of quality-assuring glass slides before they are read by a pathologist due to the significant increase in the number of glass slides that are prepared.
[0010] Therefore, what is needed is a system and method that overcomes these significant problems found in the conventional systems as described above.
SUMMARY
[0011] Accordingly, described herein are systems and methods for improving quality assurance in pathology using digital slide tools for assessing slide quality to trigger (i) preparation of new glass slides, (ii) re-scanning of glass slides, or (iii) enhancement of digital slides prior to interpretation by the pathologist. Digital slides created by slide scanning instruments contribute to improved diagnosis by pathologists by providing an automatic, systematic, objective, and consistent means for digital slide creation and analysis, enabling the use of computer implemented image analysis and image correction tools.
[0012] A digital pathology system (slide scanning instrument and software) assesses and improves the quality of a digital slide. The improved digital slide has a higher image quality that results in increased efficiency in the interpretation of such digital slides when they are viewed on a monitor by a pathologist. These improved digital slides yield a more objective diagnosis than reading the corresponding glass slide under a microscope.
[0013] Other features and advantages of the present invention will become more readily apparent to those of ordinary skill in the art after reviewing the following detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The details of the present invention, both as to its structure and operation, may be gleaned in part by study of the accompanying drawings, in which like reference numerals refer to like parts, and in which:
[0015] FIG. 1 is a flow diagram illustrating a conventional process for quality assurance using glass slides;
[0016] FIG. 2 is a flow diagram illustrating a process for quality assurance using digital slides according to an embodiment of the invention;
[0017] FIG. 3 is a flow diagram illustrating an alternative process for quality assurance using digital slides according to an embodiment of the invention;
[0018] FIG. 4 is a flow diagram illustrating an alternative process for quality assurance using digital slides according to an embodiment of the invention;
[0019] FIG. 5 is a network diagram illustrating a digital pathology system for improved quality assurance in pathology according to an embodiment of the invention; and
[0020] FIG. 6 is a block diagram illustrating an example computer system that may be used in connection with various embodiments described herein.
DETAILED DESCRIPTION
[0021] Certain embodiments as disclosed herein provide for systems and methods for quality assurance in pathology. After reading this description it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example only, and not limitation. As such, this detailed description of various alternative embodiments should not be construed to limit the scope or breadth of the present invention as set forth in the appended claims.
[0022] FIG. 2 is a flow diagram illustrating a process for quality assurance using digital slides according to an embodiment of the invention. The illustrated process can be carried out by a digital pathology system such as that later described with respect to FIG. 5 . Initially, in step 200 the glass slide is prepared in the conventional manner. Next, in step 210 the glass slide is scanned (digitized) to create a high quality digital slide image of the glass slide at a diagnostic resolution for the tissue type. Once the digital slide is created, computer implemented digital slide analysis tools are automatically applied to the slide in step 220 to assess the quality of the digital slide image. For example, the color and focus of a digital slide can be analyzed by quality modules that consider image attributes that include the contrast, brightness and spatial resolution of individual and groups of pixels in the digital slide image. If the quality of the digital slide is insufficient, as determined in step 230 , the corresponding glass slide can be rejected and an operator can prepare a new glass slide. If the quality of the digital slide is sufficient for diagnosis, as determined in step 230 , then the digital slide can be analyzed and interpreted by a pathologist, who views the digital slide on the monitor at a local or remote viewing station. Alternatively, glass slides in which the quality of the corresponding digital slide is determined to be sufficient by the computer implemented digital slide analysis tools, could be interpreted by a pathologist using a microscope.
[0023] In one embodiment, the digital slide quality assessment is made by comparing objective characteristics of the digital slide against a predetermined set of criteria. Advantageously, this provides a consistent and standard level of quality in any digital slide image that can be systematically applied to all digital slides destined for review by a pathologist.
[0024] Additionally, in one embodiment the digitizing and automatic assessment of the digital slide may be employed for the sole purpose of removing this task from the histotechnologist, thereby allowing that person to perform other tasks and improve efficiencies. In such an embodiment, the histologist may be notified of borderline quality slides in order to make the final determination of quality for a significantly fewer number of glass slides.
[0025] FIG. 3 is a flow diagram illustrating an alternative process for quality assurance using digital slides according to an embodiment of the invention. The illustrated process can be carried out by a digital pathology system such as that later described with respect to FIG. 5 . The process in FIG. 3 is initially similar to the process described with respect to FIG. 2 so only the differences will be described here.
[0026] Once the glass slide is prepared and digitized and analyzed by the digital slide analysis tools and quality modules, if the quality of the digital slide is insufficient, as determined in step 330 , the digital slide image can be rejected and an operator can rescan the glass slide. This can be more efficient if, for example, the digital slide image was rejected due to problems with focus or even problems with too much staining. In one embodiment, a rescan of a glass slide with too much staining can be done with decreased light during scanning in order to account for the over staining. Advantageously, this saves significant time in the overall process and also saves the native tissue source and other goods used in glass slide preparation.
[0027] Once a digital image of sufficient quality is created, as determined in step 330 , the system next applies computer implemented digital slide enhancement tools to improve the quality of the digital slide image even further, as shown in step 340 . For example, the colors of stains can be enhanced or even changed to provide more color contrast in counterstained samples. After the quality assured and image enhanced digital slide is ready, then in step 350 the digital slide can be analyzed and interpreted by a pathologist, who views the digital slide on the monitor at a local or remote reviewing station.
[0028] In one embodiment, when a digital slide meets the predetermined quality criteria and is then improved by computer implemented digital enhancement, the improved digital slide is fed into a clinical decision support system that guides the pathologist through the process of making an interpreting the slide in order to arrive at a diagnosis for the slide, or the case associated with the slide.
[0029] A few variations in the process shown in FIG. 3 are also possible. For example, if the image quality of the digital slide as determined in step 320 is poor then a new glass slide maybe prepared rather than rescanning the original glass slide. Additionally, providing digital enhancements to the digital slide image is not a necessary step in the process although it provides potentially significantly improved images and can facilitate a more accurate diagnosis by the pathologist.
[0030] In one embodiment, the quality assurance system described herein includes using the slide scanning instrument to assess the quality of the glass slide being scanned, and in the event that the glass slide fails predetermined quality criteria, the scanning parameters of the scanning instrument are modified to create a digital slide with improved quality. For example, a slide that is over stained (too dark) would be automatically re-scanned with less light. The determination of whether the glass slide meets predetermined quality criteria can be achieved by initially scanning the glass slide at low or high power and then performing certain types of image analysis on the resulting image to determine, as in the above example, if the slide is too dark.
[0031] FIG. 4 is a flow diagram illustrating an alternative process for quality assurance using digital slides according to an embodiment of the invention. The illustrated process can be carried out by a digital pathology system such as that later described with respect to FIG. 5 . Initially, in step 400 a glass slide is digitized and then in step 410 the digital slide is automatically evaluated against a set of predetermined criteria to assess the digital slide quality. In step 420 , slides that meet or exceed the objective baseline for digital slide quality are then digitally enhanced where possible and then the digital slide is provided to a pathologist for review and analysis, as shown in step 430 .
[0032] Advantageously, the embodiment shown in FIG. 4 is a highly streamlined computer implemented process. A plurality of slides may be provided to the digital microscopy system for automatic serial or parallel scanning that results in the digital slides being provided to a local or remote pathologist for analysis and diagnosis.
[0033] In one embodiment, examples of the types of enhancements made in step 420 to improve the digital slide image prior to diagnosis by a pathologist include enhancement of contrast, color, elimination of defects, and the like including other image processing techniques.
[0034] For example, color space standardization can be used to transform the digital slide image into a standardized or non-standardized (and better) color space. Doing so can ensure that digital slides displayed on a monitor appear more consistent in color than the corresponding glass slides would appear under a microscope. Additionally, image processing can apply image enhancement filters (e.g., sharpening, deconvolution, etc.) to the digital slide to enhance spatial details that are not readily apparent to the naked eye. Also, quality assessments can be computed to provide the pathologist an objective computer-generated measure of digital slide quality that informs the pathologist about the underlying integrity of the digital slide. This can be particularly advantageous to a pathologist because knowing that the digital slide quality is suboptimal (e.g, because of poor sample preparation) can be helpful to a pathologist. For example, if the result of a diagnosis of a suboptimal digital slide required surgery, the pathologist may instead order a new glass slide to be prepared and digitized in order to conduct a second review and analysis of the tissue.
[0035] Image pattern recognition can also be employed, for example, as part of a decision support system, to automatically identify for a pathologist those regions of a digital slide which have diagnostic significance. This can be very helpful and provide a pathologist with the ability to interrogate regions of one or more digital slides in priority order. Additionally, content based image retrieval can be extremely useful by providing the pathologist with previously diagnosed (i.e., “solved” cases) that have similar image patterns to the digital slide being analyzed. In one embodiment, a database of digital slides or other images can be accessed to retrieve digital slides or other images that show characteristics similar to the digital slide under review.
[0036] FIG. 5 is a network diagram illustrating a digital pathology system 500 for improved quality assurance in pathology according to an embodiment of the invention. In the illustrated embodiment, the system 500 comprises a slide scanner 510 that is communicatively coupled with a slide reviewer station 520 via a network 530 .
[0037] The slide scanner 510 can be any of a variety of digital slide creation systems including image tiling systems, array scanning systems, or line scanning systems, including line scanning systems utilizing time-delay-integration (“TDI”). The line scanning systems are preferred because they create digital slides more rapidly and also because the resulting digital slide images have a much higher quality both in terms of better focus and reduced artifacts such as stitching that are typically introduced by image tiling systems.
[0038] The slide scanner functions to digitize a glass slide and store the digital slide in the data storage area 515 . Also stored in the data storage area 515 are digital slide analysis tools and modules that can be implemented by the slide scanner 510 to assess the quality of a digital slide. Additionally, digital slide enhancement tools and modules that can be implemented by the slide scanner 510 to improve the quality of a digital slide are also stored in the data storage area 515 . These analysis and enhancement tools may also be stored in a separate local or remote data storage area (not shown), for example to conserve processor power at the scanning station and to allow another device to perform the analysis and enhancement functions.
[0039] The slide reviewer station 520 can be in communication with the slide scanner 510 either directly (not shown) or via the network 530 , which may be a local or wide area network, public or private network, and may or may not include that global combination of networks that is commonly known as the Internet. The slide reviewer station 520 is configured with its own data storage area 525 and allows a pathologist or other analyst (e.g., histotechnologist) to review digital slides that are stored at the slide scanner 510 or at the slide reviewer station 520 .
[0040] In one embodiment, slides are digitally scanned, their image quality is assessed and slides with sufficient quality are digitally enhanced and then subsequently sent via a network to the reviewing station of a pathologist for analysis. This entire process can be automated, for example by the presence of a barcode on the glass slide that provides information about where the send the enhanced digital slide image for analysis by the pathologist.
[0041] FIG. 6 is a block diagram illustrating an example computer system 550 that may be used in connection with various embodiments described herein. For example, the computer system 550 may be used in conjunction with the slide scanner system or slide reviewer system previously described with respect to FIG. 5 . Other computer systems and/or architectures may also be used, as will be clear to those skilled in the art.
[0042] The computer system 550 preferably includes one or more processors, such as processor 552 . Additional processors may be provided, such as an auxiliary processor to manage input/output, an auxiliary processor to perform floating point mathematical operations, a special-purpose microprocessor having an architecture suitable for fast execution of signal processing algorithms (e.g., digital signal processor), a slave processor subordinate to the main processing system (e.g., back-end processor), an additional microprocessor or controller for dual or multiple processor systems, or a coprocessor. Such auxiliary processors may be discrete processors or may be integrated with the processor 552 .
[0043] The processor 552 is preferably connected to a communication bus 554 . The communication bus 554 may include a data channel for facilitating information transfer between storage and other peripheral components of the computer system 550 . The communication bus 554 further may provide a set of signals used for communication with the processor 552 , including a data bus, address bus, and control bus (not shown). The communication bus 554 may comprise any standard or non-standard bus architecture such as, for example, bus architectures compliant with industry standard architecture (“ISA”), extended industry standard architecture (“EISA”), Micro Channel Architecture (“MCA”), peripheral component interconnect (“PCI”) local bus, or standards promulgated by the Institute of Electrical and Electronics Engineers (“IEEE”) including IEEE 488 general-purpose interface bus (“GPIB”), IEEE 696/S-100, and the like.
[0044] Computer system 550 preferably includes a main memory 556 and may also include a secondary memory 558 . The main memory 556 provides storage of instructions and data for programs executing on the processor 552 . The main memory 556 is typically semiconductor-based memory such as dynamic random access memory (“DRAM”) and/or static random access memory (“SRAM”). Other semiconductor-based memory types include, for example, synchronous dynamic random access memory (“SDRAM”), Rambus dynamic random access memory (“RDRAM”), ferroelectric random access memory (“FRAM”), and the like, including read only memory (“ROM”).
[0045] The secondary memory 558 may optionally include a hard disk drive 560 and/or a removable storage drive 562 , for example a floppy disk drive, a magnetic tape drive, a compact disc (“CD”) drive, a digital versatile disc (“DVD”) drive, etc. The removable storage drive 562 reads from and/or writes to a removable storage medium 564 in a well-known manner. Removable storage medium 564 may be, for example, a floppy disk, magnetic tape, CD, DVD, etc.
[0046] The removable storage medium 564 is preferably a computer readable medium having stored thereon computer executable code (i.e., software) and/or data. The computer software or data stored on the removable storage medium 564 is read into the computer system 550 as electrical communication signals 578 .
[0047] In alternative embodiments, secondary memory 558 may include other similar means for allowing computer programs or other data or instructions to be loaded into the computer system 550 . Such means may include, for example, an external storage medium 572 and an interface 570 . Examples of external storage medium 572 may include an external hard disk drive or an external optical drive, or and external magneto-optical drive.
[0048] Other examples of secondary memory 558 may include semiconductor-based memory such as programmable read-only memory (“PROM”), erasable programmable read-only memory (“EPROM”), electrically erasable read-only memory (“EEPROM”), or flash memory (block oriented memory similar to EEPROM). Also included are any other removable storage units 572 and interfaces 570 , which allow software and data to be transferred from the removable storage unit 572 to the computer system 550 .
[0049] Computer system 550 may also include a communication interface 574 . The communication interface 574 allows software and data to be transferred between computer system 550 and external devices (e.g. printers), networks, or information sources. For example, computer software or executable code may be transferred to computer system 550 from a network server via communication interface 574 . Examples of communication interface 574 include a modem, a network interface card (“NIC”), a communications port, a PCMCIA slot and card, an infrared interface, and an IEEE 1394 fire-wire, just to name a few.
[0050] Communication interface 574 preferably implements industry promulgated protocol standards, such as Ethernet IEEE 802 standards, Fiber Channel, digital subscriber line (“DSL”), asynchronous digital subscriber line (“ADSL”), frame relay, asynchronous transfer mode (“ATM”), integrated digital services network (“ISDN”), personal communications services (“PCS”), transmission control protocol/Internet protocol (“TCP/IP”), serial line Internet protocol/point to point protocol (“SLIP/PPP”), and so on, but may also implement customized or non-standard interface protocols as well.
[0051] Software and data transferred via communication interface 574 are generally in the form of electrical communication signals 578 . These signals 578 are preferably provided to communication interface 574 via a communication channel 576 . Communication channel 576 carries signals 578 and can be implemented using a variety of wired or wireless communication means including wire or cable, fiber optics, conventional phone line, cellular phone link, wireless data communication link, radio frequency (RF) link, or infrared link, just to name a few.
[0052] Computer executable code (i.e., computer programs or software) is stored in the main memory 556 and/or the secondary memory 558 . Computer programs can also be received via communication interface 574 and stored in the main memory 556 and/or the secondary memory 558 . Such computer programs, when executed, enable the computer system 550 to perform the various functions of the present invention as previously described.
[0053] In this description, the term “computer readable medium” is used to refer to any media used to provide computer executable code (e.g., software and computer programs) to the computer system 550 . Examples of these media include main memory 556 , secondary memory 558 (including hard disk drive 560 , removable storage medium 564 , and external storage medium 572 ), and any peripheral device communicatively coupled with communication interface 574 (including a network information server or other network device). These computer readable mediums are means for providing executable code, programming instructions, and software to the computer system 550 .
[0054] In an embodiment that is implemented using software, the software may be stored on a computer readable medium and loaded into computer system 550 by way of removable storage drive 562 , interface 570 , or communication interface 574 . In such an embodiment, the software is loaded into the computer system 550 in the form of electrical communication signals 578 . The software, when executed by the processor 552 , preferably causes the processor 552 to perform the inventive features and functions previously described herein.
[0055] Various embodiments may also be implemented primarily in hardware using, for example, components such as application specific integrated circuits (“ASICs”), or field programmable gate arrays (“FPGAs”). Implementation of a hardware state machine capable of performing the functions described herein will also be apparent to those skilled in the relevant art. Various embodiments may also be implemented using a combination of both hardware and software.
[0056] Furthermore, those of skill in the art will appreciate that the various illustrative logical blocks, modules, circuits, and method steps described in connection with the above described figures and the embodiments disclosed herein can often be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled persons can implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the invention. In addition, the grouping of functions within a module, block, circuit or step is for ease of description. Specific functions or steps can be moved from one module, block or circuit to another without departing from the invention.
[0057] Moreover, the various illustrative logical blocks, modules, and methods described in connection with the embodiments disclosed herein can be implemented or performed with a general purpose processor, a digital signal processor (“DSP”), an ASIC, FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor can be a microprocessor, but in the alternative, the processor can be any processor, controller, microcontroller, or state machine. A processor can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
[0058] Additionally, the steps of a method or algorithm described in connection with the embodiments disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium including a network storage medium. An exemplary storage medium can be coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The processor and the storage medium can also reside in an ASIC.
[0059] The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent a presently preferred embodiment of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art and that the scope of the present invention is accordingly not limited. | Systems and methods for analyzing digital slide images. In an embodiment, a digital slide image is acquired from a specimen on a slide. Then, until it is determined that a quality of the digital slide image is sufficient, the quality of the digital slide image is determined and the digital slide image is reacquired. Once it is determined that the quality of the digital slide image is sufficient, the digital slide image and a measure of the quality of the digital slide image is provided to one or more recipients. | 6 |
FIELD OF INVENTION
This invention relates to seafood processing and more particularly to the extraction of meat from crab claws.
BACKGROUND OF INVENTION
The removal of meat from the bodies and appendages of crustaceans such as crabs have historically been accomplished by hand. This is particularly true in removing the meat from blue crabs found on the eastern seaboard of the United States which are considerably smaller than dungeness and snow crab found on the West Coast of the country.
Skilled workers, commonly referred to as crab pickers, work in crab houses picking the cooked crab meat from the bodies of the crabs. Machines and apparatuses have been developed to separate edible crab meat from nonedible portions of the crab body but almost invariably more fragments of crab shells are found in the meat following this process than is found in crab meat hand picked by crab pickers.
There is a considerable amount of meat in the bodies of East Coast blue crabs and is relatively easy to extract by hand. The claws of these crabs, however, are relatively small, certainly as compared to the claws of dungeness and snow crabs, and are hard and difficult to crack. For this reason, blue crab claws are quite often frozen and sold separately as hors d'oeuvres or the like due to the difficulty of extracting meat therefrom.
A number of machines and apparatuses have been developed for extracting meat from the appendages of crustaceans but a majority of these have been for removing the meat from the legs and claws of the large dungeness, snow and king crab, rather the much smaller pincer claws of the eastern blue crab. These various crab claw meat extracting apparatuses cut the shell or the entire claw to expose the meat in the interior of such claw. This cutting process is usually circumventially around the claw to separate one end from the other end or a transverse cut through the entire claw. In either case, rather large areas of claw shell are cut which greatly increases the chance of splintered shell or shell dust from contaminating the claw meat being extracted.
CONCISE EXPLANATION OF PRIOR ART
U.S. Pat. No. 4,785,502 to Howard discloses an apparatus for extracting the meat from crustacean appendages including the utilization of pressurized air injected into the appendage to expel the meat therefrom.
U.S. Pat. No. 4,021,886 to Crepeau discloses an apparatus for scoring crab claws circumventially so that one end of the shell can be separated from the other end. See particularly FIG. 5.
U.S. Pat. No. 3,135,992 to Fredrickson discloses a method of producing shelled crab claws including bisecting the shell of the bulb portion of a king crab claw longitudinally to expose the meat within the claw. See particularly FIG. 11.
U.S. Pat. No. 4,316,306 to Huebotter discloses a method and apparatus for holding the pincer carrying leg of a crab for splitting the leg and pincer longitudinally to expose the meat therein. See particularly FIG. 5.
U.S. Pat. No. 4,003,103 to Wenstrom et al discloses an apparatus for separating edible crab meat from nonedible body portions of cooked crabs after the top shell has been removed therefrom.
U.S. Pat. No. 4,124,920 discloses a method of separating edible crab meat from nonedible body portions of cooked crabs which is a division of U.S. Pat. No. 4,003,103 and is based on a continuation-in-part thereof.
U.S. Pat. No. 4,535,507 is a method and apparatus for removing lump meat from blue crabs including cutting the crabs so that they can be hand picked with a special tool.
U.S. Pat. No. 3,022,175 is a method of preparing king crab legs including freezing of the same and enclosing such legs in a moisture impervious sheet.
U.S. Pat. No. 2,784,447 is a crab cleaning machine for removing the top shells and gills of crabs and washing the same in an automatic operation.
U.S. Pat. No. 3,750,234 to Rodgers et al discloses a crab picking machine wherein cooked crabs are elevated and allowed to fall on a shaker screen wherein the fall impact breaks up the crabs allowing the parts to be separated.
U.S. Pat. No. 3,455,668 to Wenstrom discloses an apparatus for separating edible crab meat from nonedible portions from cooked crab bodies including violently impacting such crabs against a chamber wall.
Finally, U.S. Pat. No. 4,321,730 to Tolley et al discloses a core box supporting means for vibratory type processing machines where meat is removed from the body of crabs.
BRIEF DESCRIPTION OF INVENTION
After much research and study into the above-mentioned problems, the present invention has been developed to extract meat from crab claws in a highly-efficient manner while reducing to an absolute minimum the chance of pieces of shell contaminating such meat.
The above is accomplished by sizing the crab claws from which the meat is to be extracted, cutting the pincer end of the claws and the body joint end of the attached claw arm so that the interior of the claws and claw arms communicate with the exterior thereof, moving the thus prepared claws to an endless conveyor with inverted V-shape openings therein, holding the claws and attached arms on said conveyor and rapidly vibrating the same to remove the crab meat from the interior thereof, and discharging the empty shells from said conveyor.
The above is accomplished with a minimum of labor while removing larger amounts of meat than can ordinarily be removed by hand, with few or no pieces of shell contaminating the meat, in much less time than such process can be accomplished manually.
In view of the above, it is an object of the present invention to provide a highly-efficient means and method of extracting meat from crab claws.
Another object of the present invention is to provide a means and method of extracting meat from crab claws with a minimum amount of cutting of the claw shell.
Another object of the present invention is to provide a means and method of extracting meat from crab claws including cutting of the ends of the pincers of the claw and the end of the claw arm adjacent the body joint followed by placing the joined crab claw and arm in an inverted V holder and vibrating the same to remove the claw meat therefrom.
Another object of the present invention is to place a joined crab claw and arm on an inverted V in cross section holder with the knuckle joint therebetween being at the apex of the V and cutting the pincer end of the claw and the body joint end of the arm prior to vibrationally removing the meat from said claw and arm.
Other objects and advantages of the present invention will become apparent and obvious from a study of the following description and accompanying drawings which are merely illustrative of such invention.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of the crab claw meat extractor of the present invention;
FIG. 2 is a somewhat schematic side elevational view of the crab claw conveyor along with the claw cutting means;
FIG. 3 is a sectional view taken through lines 3--3 of FIG. 2;
FIG. 4 is a top perspective view of the crab claw carrier;
FIG. 5 is an enlarged sectional view of the crab claw carrier mounted on the chain drive of the claw conveyor;
FIG. 6 is an elevational view of a crab claw including its pincer and claw arm disposed on the crab claw carrier;
FIG. 7 is a top plan view of a claw receiving pad;
FIG. 8 is a sectional view taken through lines 8--8 of FIG. 7; and
FIG. 9 is a somewhat schematic sectional view of the crab meat extracting apparatus of the present invention.
DETAILED DESCRIPTION OF INVENTION
With further reference to the drawings, the crab claw meat extractor of the present invention, indicated generally at 10, includes a crab claw cutting portion, indicated generally at 11 and a meat extraction portion, indicated generally at 12.
The crab cutting portion 11 includes work tables 13 on opposite sides thereof with a crab claw conveyor 14 therebetween.
The worktables 13 are provided at a convenient height that workers can take crab claws from the worktables 13 and place the same on the crab claw conveyor 14 as will hereinafter be described in greater detail.
The crab claw conveyor 14 includes a carrier chain 15 that is trained over sprockets 16 and 17, idler sprocket 18 and drive sprocket 19. Drive sprocket 19 is operatively attached to drive motor 20 in the normal manner. Since the operation of drive chains, sprockets and drive motors are well known to those skilled in the art, further detailed discussion of the same is not deemed necessary.
A plurality of crab claw carriers 21 are provided and are operatively mounted on drive chain 15. These crab claw carriers are inverted V-shaped in cross section with sloping sides 22 with a peak 23.
The rear of each of the crab claw carriers has an end wall 24 with forwardly rolled flanges 25 as can clearly be seen in FIG. 4.
The crab claw cutting portion 10 of the present invention includes a conveyor loading station 26, a claw cutting station 27 and a claw from waste separating station 28.
The meat extraction portion 12 includes a carrier belt loading station 29, a meat from shell separating station 30 and a claw shell waste removal station 31.
Disposed between conveyor chain sprockets 16 and 17 is a chain bar 32 which supports the conveyor chain 15. The conveyor chain 15 is adapted to move in the direction shown by arrow 33 in FIG. 2.
Near the end of the direction of travel of the conveyor chain 15, and in the area adjacent sprocket 17 which reverses the direction of travel of said chain, are a pair of cutting motors 34 and 35. Each of these motors has a drive shaft 34' and 35', respectively, with circularly cutting blades 36 and 37 operatively mounted thereon.
Each of the cutting motors 34 and 35 are mounted on support means 38 and 39 that are pivoted as indicated at 38' and 39'. The end of each of the support means 38 and 39, opposite their respective pivots 38' and 39', are connected to threaded jack shafts 40 and 41, respectively. When the handles 40' and 41' of the respective jack shafts 40 and 41 are manipulated, the motors 34 and 35 can be raised or lowered as can clearly be seen in FIG. 3.
An inverted V-shaped-in-cross-section crab claw hold-down bar 42 is provided above the conveyor chain 15 and its associated crab claw carriers 21 in the claw cutting station 27. This hold-down bar 42 is mounted on downwardly biased springs 43 on hold-down bar frame 44. This arrangement allows the hold-down bar to hold the claws in place during the cutting operation due to the bias of springs 43 while at the same time allowing said bar to floatingly ride thereon to automatically adjust to slight changes in the size of the claws passing thereunder as will hereinafter be described in greater detail.
The common blue crab that is commercially harvested from the Gulf and Atlantic Coasts has five pairs of legs. The front pair of legs, commonly referred to as crab claws, indicated generally at 64, are pincer carrying and include a crab claw arm 45 that has a body joint end 46 with the other end connected to knuckle joint 47. The opposite side of this joint is connected to the pincer 48. The pincer includes a stationary jaw 49 and a movable jaw 50.
When the body joint 46 of the claw arm 45 and at least a portion of the jaws 49 and 50 are cut from the crab claw 64, the waste is ejected through chute 51 in the bottom of cutting station 27 into either a receptacle (not shown) or onto a cross conveyor 51' for removal. The thus cut crab arm 45 and pincer 48 with the connecting joint 47 are then dropped off the end of conveyor 14 adjacent sprocket 17 and pass out slide chute 52 onto the side trays 29' of the carrier belt loading station 29.
A relatively wide conveyor belt 53 is operatively mounted on support rollers 54 and 55. Since conveyor belts and support rollers are well known to those skilled in the art, further detailed discussion of this part of the present invention are not deemed necessary.
Spaced along and supported by conveyor belt 53 are a plurality of claw receiving pads 55. These pads can either be mounted on the conveyor belt 53 or they can be part of said belt. These pads are preferably made from neoprene or similar material and have a plurality of paired openings extending outwardly from each other at an angle that will allow the arm 45 and pincer 48 of the crab claw 64 to be inserted thereinto with the knuckle joint 47 at the apex of the openings.
The claw receiving pads of areas 55 are preferably rectangular in shape and are so sized that they fit within the shaker box 57 operatively mounted within the meat separating station 30.
Inside the shaker box 57 and above the claw receiving pads 55 is a hold-down means 59. This hold-down means can be a neoprene pad or the like that can be either inflated or lowered into contact with the crab claws 64 disposed in the slanted, paired openings 56.
A shaker means 62 is operatively attached to shaker box 57 to vibrate the same between 1,500 and 5,000 vibrations per minute to shake the crab meat from the claw arm and pincer. One method of vibrating the crab meat from the connected arm and pincer would be the vibratory apparatus disclosed in U.S. Pat. Number 4,003,103 (now expired). Other vibratory means could, of course, be used to obtain the same results.
A lateral or cross conveyor 58 can be provided under the shaker box 57 to remove the extracted crab meat to an area for packing or further processing. Cross conveyors of this type are well known to those skilled in the art and further detailed discussion of the same is not deemed necessary.
The process of removing the crab meat from the claw arm and pincer is an incremental process with the pad 55 moving in place within shaker box 57, the hold-down means 59 moving against the pad 55, the pad 55 being vibrated to remove the crab meat from the pincer and arm, and then the hold-down cushion moving out of contact with such pad and the same moving from the shaker box and the next pad moving thereinto. As this process continues each pad will move around the end support roller 54 and will be inverted as can clearly be seen on the right hand side of the sectional schematic of FIG. 9. A means is then used to remove the arm and pincer shells of the crab claws 64 from each of the pads. This can be accomplished through the use of high pressure fluids such as air or water nozzles 60 which are aimed down the bore of each of the openings 56 in pad 55. These shells will fall into chute 61 and from there onto cross conveyor 62 for removal and disposal.
When any given pad 55 moves back in place adjacent the side trays 29' of station 29, the same is ready for reloading with the trimmed crab claws 64.
The means or method of using the crab claw meat extractor of the present invention includes taking a plurality of crab claws 64, including pincers and attached arms, that have been graded to the same size and placing such graded claws on the work tables 13 of the conveyor loading station 26. Workers standing on either side thereof can then place multiple crab claws 64 on the crab claw carrier 21 mounted on the conveyor drive chain 15. When one of the crab claw carriers 21 is full then the next one is filled, etc. The crab claw conveyor 14 moves steadily in the direction of the arrow 23 and each of the claw carriers 21 passes under spring-biased hold-down bar 42 when it enters the claw cutting station 27.
The handles 40' and 41' of the respective threaded jack shafts 40 and 41 are adjusted to set the position of the respective cutting motors 34 and 35 and their associated blades 36 and 37 to the correct height for the size crab claws 64 being processed at the time.
As the claws pass through the cutting station 27, the cutting blade 36 will sever the pincer jaws 49 and 50 at the preset location and blade 37 will sever the body joint end 46 of the crab claw arm 45 opposite knuckle joint 47. The cut or waste jaws 49 and 50 and arm end 46 will drop through chute 51 and either into a receptacle (not shown) or onto a lateral conveyor 51' to remove the same for disposal.
As the crab claw carrier 21 with its associated trimmed crab claws 64 passes around sprocket 17, which is past hold-down bar 42, such crab claws will fall into slide chute 52 and be deposited on the trays 29' at the belt loading station 29.
Workers standing on either side of the side trays 29' can take the crab claws 64 and insert the claw arm in one of the paired holes 56 and the pincer in the other with the knuckle joint 47 at the top.
Once each of the pads 55 has been filled, it can be moved by conveyer 53 until it enters the meat-from-shell separating station 30. At that point the hold-down cushion 59 presses down against the pad 55 and its inserted crab claws. With the cushion in place to hold the crab claws in the holes 56 of pad 57, the shaker box is vibrated in the range of 1,500 to 5,000 vibrations per minute for a predetermined period of time until the meat within the crab claw pincer and arm has vibrated therefrom and has fallen onto lateral conveyor 58. The hold-down cushion 59 is then raised and the pad thereunder moved in the direction shown by arrow 33' a distance equal to the length of the pad so that the next pad is disposed beneath the hold-down cushion 59. The shaking process is then repeated.
As the pads 55 with their associated de-meated pincer and arm shells moves above disposal chute 61, fluid jets 60 of water, air or the like are directed down the bore of each of the angled holes 56 to remove such shells therefrom. Once the holes have been emptied, the pad above the chute will move therefrom as the shaker process is completed for subsequent pads. The cross or lateral conveyor 56 can be used to remove the empty shells for disposal.
As the empty pads 55 move around roller 54 and are again adjacent to the side trays 29' of the belt loading station 29, the workers (not shown) can again fill such pads so that the vibratory crab claw meat removal process can sequentially be continued until all the crab claws 64 have had the meat extracted therefrom.
From the above it can be seen that the present invention provides a highly efficient method of extracting the meat from crab claws including the pincer portions and arm portions thereof. The apparatus for accomplishing this operates in an endless cycle and is simple and yet highly efficient. The present invention provides a means for extracting the meat from crab claws with very little if any contamination of shells with the meat during such process.
The present invention can, of course, be carried out in other ways than those herein set forth without departing from the spirit and essential characteristics of such invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein. | This invention is a means and method for mechanically removing the meat from crab claw pincers and their attached claw arms. This is accomplished by placing the claws on a conveyor and holding the same in position prior to and during cutting of the claw pincer jaw ends and attached claw arm body joint ends. The cut claws are placed in paired diverging openings in pads with the cut ends disposed downwardly. The pads are then conveyed into a vibratory meat extracter where the meat within the cut claws is extracted therefrom prior to removing the remains of the claws from the pad and returning such pad for reloading. | 0 |
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/099,827, filed Sep. 10, 1998.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a method and apparatus for downhole safety valve remediation using controlled detonation of a measured explosive charge.
2. Description of the Related Art
Subsurface safety valves are commonly used in wells to prevent uncontrolled fluid flow through the well in the event of an emergency, such as to prevent a well blowout. Conventional safety valves use a flapper, which is biased by a spring to a normally closed position, but is retained in an open position by the application of hydraulic fluid operating on a rod piston connected to the flapper valve from the earth's surface. A typical surface controlled subsurface safety valve (“SCSSV”) is shown and described in U.S. Pat. No. 4,161,219, which is commonly assigned hereto.
Through normal operation of a well, scale and other debris can build up on the inner surface of the well tubing. In addition to the well tubing surface build-up, however, scale, asphaltines, and other debris can also build up within the bore of the safety valve as well as on the mechanical parts of the safety valve, themselves, to render the safety valve either more difficult to operate or even totally inoperative. Various methods and apparatus have been employed to remediate safety valves after such a scale or debris build-up. For example, coiled tubing has been used in connection with an orifice nozzle to remove the scale or debris build-up with fluid pressure. Further, a running tool may be used to remediate the valve. The running tool may have a tool profile adapted to mate with a well profile associated with the desired valve. When the tool reaches the desired location within the well, the tool may then be engaged within the well profile and mechanical force is applied to the tool, jerking the tool back and forth in hopes of freeing the valve from the binding force of the scale or other debris build-up. As an additional example, in the event the valve is stuck in the closed, or sealing, position a simple rod may be lowered into the well to the desired location within the safety valve and mechanical force is applied to mechanically beat downward on the flapper or other sealing member within the valve body in hopes that the mechanical force will overcome the binding force of the scale or other debris build-up within the valve.
There are other safety valve failures or problems that may arise that require safety valve remediation in a typical well operation. For example, a typical safety valve, as described above, may be maintained in its open position by maintaining hydraulic pressure through a hydraulic control line within the well casing extending from the safety valve to a source of hydraulic pressure at the well surface. In the event of, for example, a hydraulic pressure leak in the hydraulic control line or a hydraulic pump failure, hydraulic pressure may not be maintained to the safety valve. In such a situation, it may not be possible to maintain the safety valve in its fully open position in which case production fluid may be partially or completely restricted through the safety valve. It may not be possible or desirable to remove the safety valve in such a situation; therefore, various methods and apparatus have been employed to remediate safety valves in such a situation. Typically, a wireline inset valve may be inserted into the safety valve to lock out the valve to maintain the valve in its open position and permit production fluid to continue to flow through the valve. However, such methods and apparatus may be expensive and may not be desirable in a particular application.
Explosive charges have been employed in certain well operations, particularly in certain downhole electric line well operations. Previously, explosive charges have been used, for example, to: perforate well casing and any surrounding formation to permit fluid flow into the well casing from the formation; set and release packers for sealing off between the well casing and production tubing extending through the casing; and break up scale or other debris build-up from, for example, threaded tools or tubing joints to facilitate removing the tools or tubing string from the well. However, explosive forces have not heretofore been incorporated in a method or apparatus for remediation of downhole safety valves. In the case of scale and other debris build-up removal, it has not heretofore been possible or practical to effectively control the explosive forces within the safety valve body to remove the scale or other debris build-up while preventing undesirable destruction or damage to the safety valve or to lockout a defective safety valve while preventing or minimizing damage to proximate tubing or other apparatus within the well.
The prior methods and apparatus have not previously provided an adequate remediation solution for safety valves. Accordingly, there has developed a need to provide a method and apparatus for downhole safety valve remediation using precisely controlled explosive forces to remove scale and other debris build-up or to lockout a defective safety valve. The present invention has been contemplated to meet this need.
SUMMARY OF THE INVENTION
In a broad aspect, the invention is a downhole safety valve remediation method using detonation of an explosive charge to break up scale, asphaltics, and/or other debris build-up from within and around the safety valve. In another aspect, the invention is a downhole safety valve remediation apparatus having a means for pre-determining certain well conditions that must exist before permitting detonation of an explosive charge so that the charge may be precisely located before detonation, which is used to break up the scale, asphaltics, and/or other debris build-up from within and around the safety valve.
In another aspect, the invention is a downhole safety valve remediation method using detonation of an explosive charge to lock out the safety valve so that hydraulic pressure is not required to maintain the safety valve in its open position. In another aspect, the invention is a downhole safety valve remediation apparatus having a means for predetermining certain well conditions that must exist before permitting detonation of an explosive charge so that the charge may be precisely located before detonation, which is used to lock out the safety valve so that hydraulic pressure is not required to maintain the safety valve in its open position.
In another aspect, the invention is a downhole safety valve remediation apparatus, comprising: a location means for locating a desired position within a well associated with the safety valve for detonation of an explosive charge proximate thereto, the charge being pre-selected to achieve a desired level of concussive force within the safety valve to effect remediation thereof.
In another aspect, the invention is a downhole safety valve remediation apparatus, comprising: a firing control unit; a lengthwise member connected to and extending generally away from the firing control unit; a length of primer cord operatively connected to the firing control unit and having an explosive length thereof wrapped around the lengthwise member; and a length of friction tape wrapped around the lengthwise member along the explosive length of primer cord. The firing control unit may further comprises a firing head and a detonator; and the firing head may include: a battery section housing a battery; a memory and control section, operatively connected to the battery for storing pre-selected fining parameters and for selectively controlling the flow of current between the battery and the detonator; and a monitoring section, operatively connected to the memory section for monitoring well conditions related to the pre-selected firing parameters. Further, the memory and control section may control current flow in response to the well conditions, and the memory and control section may provide current flow between the battery and the detonator when the well conditions monitored by the monitoring section are within the pre-selected firing parameters stored in the memory and control section. Still further, the firing head may further include a voltage step-up section provided between the battery section and the detonator for increasing the voltage provided between the battery and the detonator, whereby the voltage may be increased to a value of approximately 186 volts in certain preferred embodiments.
In still another aspect, the invention is a method for remediation of downhole safety valves, comprising the steps of: providing a downhole tool having an explosive charge connected thereto; lowering at least a portion of the downhole tool into a well to a position proximate the downhole safety valve to be remediated; and detonating the explosive charge. The explosive charge may be detonated using a firing control unit, which may comprise a firing head and a detonator. The firing head may include: a battery section housing a battery; a memory and control section, operatively connected to the battery for storing pre-selected firing parameters and for selectively controlling the flow of current between the battery and the detonator; and a monitoring section, operatively connected to the memory section for monitoring well conditions related to the pre-selected firing parameters. Further, the firing control unit may be located on the wireline tool proximate the explosive charge and the firing control unit may be remotely located from the explosive charge or located proximate the well surface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational side view, showing a downhole safety valve remediation apparatus of the present invention.
FIG. 1A is a partial elevational side view of the shot rod of the present invention wrapped with an explosive length of primer cord with lengths of common electrical tape and friction tape also wrapped co-extensively therearound.
FIG. 1B is a partial elevational view of an explosive length of primer cord, showing layers of common electrical tape and friction tape disposed thereon, respectively.
FIG. 1C is an elevational view of a length of primer cord, including a fuse length and an explosive length having layers of common electrical tape and friction tape disposed thereon, respectively.
FIG. 1D is a cross-sectional view taken along section A—A of FIG. 1, showing the cross- sectional configuration of the flow-through orienting sleeve of the present invention.
FIG. 2 is an elevational side view, partially in cross-section, showing the explosive portion of the remediation apparatus of the present invention lowered into a desired position within a safety valve to be remediated.
FIG. 3 is a cross-sectional side view of a detonator section of the remediation apparatus of the present invention.
FIG. 4 is a partial elevational side view of the firing head section of the remediation apparatus of the present invention.
FIG. 5 is a schematic diagram of the interoparability of various components of the remediation apparatus of the present invention.
While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to those embodiments. On the contrary, it is intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a downhole safety valve remediation apparatus of the present invention is shown. The downhole safety valve remediation apparatus preferably includes a location means 20 , or locators, for locating a desired position A within a well. The desired position A may be associated with a safety valve B (FIG. 2 ), and (as shown in FIG. 2) is preferably a position proximate to or within the interior of the safety valve B, itself. Using the method and apparatus of the present invention, the position within or otherwise associated with the safety valve may be selected with a relatively high degree of accuracy for detonation of an explosive charge proximate thereto. In addition to the selection of the position of the charge within or otherwise associated with the safety valve B prior to detonation, the charge itself may be pre-selected to achieve a precise, measured, and desired level of concussive force within the safety valve B to effect remediation thereof. Various types and intensities of charges may be selected depending on the particular form of safety valve remediation desired.
In one embodiment, the location means 20 may be of the variety commercially known as Micro-Smart SMART Blaster available from Micro-Smart System, Inc., Houston, Tex. 77053 and as disclosed and described in U.S. Pat. No. 5,369,579 to Anderson, the disclosure of which is incorporated by reference as though set forth fully herein. However, many other location means 20 , or locators, may be used. In a particular embodiment, as shown in FIG. 1, the apparatus of the present invention may comprise a firing control unit 100 ; a lengthwise member 200 , or shot rod, connected to and extending generally away from the firing control unit 100 ; a length of primer cord 300 operatively connected to the firing control unit 100 and having an explosive length el (FIG. 1C) thereof wrapped around an explosive portion 220 of the lengthwise member 200 ; and a length of friction tape 320 wrapped around the lengthwise member 200 along the explosive length el of primer cord 300 . In addition, it may be desirable to provide a length of common electrical tape 310 between the primer cord 300 and the friction tape 320 (see FIGS. 1 A- 1 C).
Preferably, with reference to FIGS. 1 and 3, the firing control unit 100 further comprises a firing head 111 and a detonator 134 , which may be located in a firing head section 110 and a detonator section 120 , respectively. Referring now to FIG. 4, the firing head 111 may preferably include: a battery section 500 ; a memory and control section 510 ; and a monitoring section 520 . In a particular embodiment, the battery section 500 may house or otherwise contain a battery 501 , which preferably may be a 5 cell lithium battery rated for temperatures up to 325°.
Preferably, the memory and control section 510 is operatively connected to both the battery 501 and the detonator 134 (FIG. 3) and includes a solid state non-volatile electronic memory 511 for acquiring and storing multiple sets of downhole data before, during, and after explosive detonation. The stored data may be retrieved after detonation by use of a computer after recovery of the remediation apparatus from the well bore for subsequent computer analysis. The memory and control section 510 may further include an electronic control circuit operatively connected to the electronic memory 511 and the monitoring section 520 described hereafter for providing electrical current from the battery 501 to the detonator 134 (FIG. 3) in response to the parameters stored in the electronic memory 511 .
The monitoring section 520 may include a variety of parameter measurement devices 521 , 522 , 523 . For example, in a particular embodiment a motion sensor 521 may be provided for measuring motion of the remediation apparatus within the well bore. A clock timer 522 may also be provided for measuring elapsed time between certain measured events such as cessation and resumption of motion of the remediation apparatus. A temperature sensor 523 may further be provided to measure the well bore temperature proximate the remediation apparatus. A static pressure transducer 524 may also be provided to measure the static pressure within the well bore proximate the remediation apparatus. In addition, other desired parameters may be measured using appropriate sensors known in the art.
The memory and control section 510 preferably provides current to the detonator 134 when the measured parameters fit within the pre-selected range of parameters stored in the electronic memory 511 by use of a central processing unit (“CPU”) 525 or fire control 525 , which receives and processes electronic logic signals being continuously received from the motion sensor 521 , clock timer 522 , pressure sensor 524 , temperature sensor 523 , or other parameter measurement devices. The CPU 525 generates an electronic detonation signal permitting electrical initiation of the detonator 134 by the electrical energy of the battery 501 only when the signal output of these sensors 521 , 523 , 524 and the clock timer 522 collectively provide the CPU 525 with firing logic signals which establish approval for the downhole detonation. If a logic signal from either of these control modules 521 - 524 is in the non-firing mode, the CPU 525 will not output a firing signal to the detonator 134 .
In a particular embodiment, a voltage step-up device 526 may be provided in connection with the firing head 111 between the battery section 500 and the detonator 134 to step up, or increase, the voltage between the battery 501 and the detonator 134 . By way of illustration only, in a particular embodiment, the voltage may be increased from about 13 volts to about 186 volts, which may improve the effectiveness or efficiency of the detonator 134 . The step up device 526 may be a resistorized device module 526 , which may include an arrangement of resistors to step up the voltage selectively applied to the detonator 134 .
Referring now to FIG. 3, in a particular embodiment the detonator 134 may be provided in a detonation chamber 136 of detonator section 130 , and may receive electrical current from the firing head 111 to initiate detonation. In a preferred embodiment, the detonator 134 is a resistor, which preferably is rated at 51 ohms. A suitable detonator 134 may be of the type generally available from Ensign-Bickford as Model No. EP105. The detonator 134 is operably connected to an explosive charge 600 , which in a preferred embodiment may be a length l of primer cord 300 in electrical contact with the detonator 134 by use of a crimp 135 or other standard fastener known in the art. With reference to FIG. 1C, in such an embodiment, the length l of primer cord 300 may comprise a fuse length fl and an explosive length el. As shown in FIG. 3, electrical current from the firing head 111 may be provided to detonator 134 through a coupling 121 , which in a particular embodiment may be a specially adapted knuckle joint 121 , through which an electrical conduit 131 is provided. Firing head 111 may include a threaded fastener portion 112 for threadable engagement within a threaded fastener portion 113 of connecting section 122 adapted to receive firing head 111 . Firing head 111 may include a coaxial electronic connector 123 from which a first and a second electrical conductor 125 and 126 , respectively, may extend within a sealed chamber 124 before passing through electrical conduit 131 provided in the specially adapted knuckle joint 121 . The knuckle joint 121 may comprise a socket portion 127 associated with the connecting section 122 , having an electrical conduit 139 formed therethrough and ball portion 132 associated with detonator section 130 , having the electrical conduit 131 formed therethrough.
The electrical conductors 125 and 126 extend from the coaxial connector 123 , through the chamber 124 , through the electrical conduits 131 , 139 formed in the ball and socket portions 132 , 127 , respectively, through the electrical conduit 133 formed in the detonator section 130 , and into the detonation chamber 136 formed in the detonator section 130 , and finally connect to electrical contacts associated with the detonator 134 . The coupling 121 permits the detonator section 130 and the shot rod 200 to move with respect to the firing head 111 upon detonation and firing of the charge 600 . Electrical current passed to the detonator 134 causes the detonator 134 to heat up, thereby igniting a section of the primer cord 300 . With reference to FIG. 1C, the fuse length fl of the primer cord 300 then burns as a fuse to the explosive length el of the primer cord 300 , as will be described in greater detail hereinbelow.
Referring now to FIG. 1, the shot rod 200 , or other lengthwise member 200 , may be operatively connected to the detonator section 120 , in the embodiment shown having a separate detonator section 120 , or is otherwise connected to the firing head 111 of the present invention. The fuse length fl of primer cord 300 may extend from the detonator 134 to a desired charge location 220 on the shot rod or lengthwise member 200 . The charge 600 used may comprise an explosive length el of primer cord 300 , which, as shown at the bottom of FIG. 1, in a particular embodiment may be spirally wrapped about the circumference of the lengthwise member 200 proximate the charge location 220 . Pre-measured gaps g may be provided between successive wraps, or windings, depending on the particular explosive characteristics desired. The type of primer cord 300 used, the explosive length el of the primer cord 300 , and the gap width g between successive wraps, or windings, thereof may be selected to achieve a predicted and controlled concussive force in the vicinity of the charge 600 . The explosive length el of the primer cord 300 may be distinguished from the fuse length fl primarily in that the explosive length el may be wrapped with a length of common electrical tape 310 and/or a length of friction tape 320 (see, e.g., FIG. 1 C), which will cause the primer cord 300 to explode with a concussive force rather than burn as a fuse.
By way of illustration only, in a preferred embodiment for locking out a defective safety valve, an approximately 70 inch length l of 80 grain/ft primer cord 300 may be wrapped along an approximately ½ inch diameter shot rod 200 having a length of approximately 5 ft. The primer cord 300 may be wrapped along an approximately thirty-inch explosive length of the shot rod 200 having a gap width g of approximately one inch. The explosive length el of primer cord 300 is then co-extensively wrapped with a length of common electrical tape 310 and a length of friction tape 320 .
Referring now to FIG. 2, the shot rod 200 is then lowered, preferably attached to the firing control unit 100 to a desired location A within an upper and lower boundary of a hydraulic chamber 700 of the safety valve B but not in a flow tube 710 in the safety valve B. Electrical detonation of the fuse length fl of primer cord 300 , which separates the detonator 134 from the explosive length el of primer cord 300 , is then provided to cause the fuse length fl of the primer cord 300 to burn as a fuse to the explosive length el of the primer cord 300 , at which point the explosive length el of the primer cord 300 explodes to create a concussive force proximate the charge 600 proximate to or within the hydraulic chamber 700 of the safety valve B. The concussive force may then cause the safety valve B to expand in diameter, thereby rendering the safety valve B inoperable, preferably locking it in the open position.
By way of another illustration only, in a preferred embodiment for removing scale or other debris build-up within the safety valve B, an approximately 70 inch length l of 40 grain/ft primer cord 300 may be wrapped along an approximately ½ inch diameter shot rod 200 having a length of approximately 5 ft. The primer cord 300 may be wrapped along an approximately thirty-inch explosive length el of the shot rod 200 having a gap width g of approximately one inch. The explosive length el of the primer cord 300 is then co-extensively wrapped with a length of common electrical tape 310 and a length of friction tape 320 .
The shot rod 200 is then lowered, preferably attached to the firing control unit 100 to a desired location A proximate to and preferably within an upper and lower boundary of the hydraulic chamber 700 of the safety valve B but not in the flow tube 710 . Electrical detonation of the fuse length fl of primer cord 300 is then provided to cause the fuse length fl of the primer cord 300 to burn as a fuse to the explosive length el of primer cord 300 , at which point the explosive length el of primer cord 300 explodes to create a concussive force proximate the charge 600 within the hydraulic chamber 700 of the safety valve B.
Referring to FIGS. 1 and 1D, a flow-thru orienting sleeve 400 may be provided and disposed around the shot rod 200 to assist in lowering the apparatus of the present invention to the desired location A (FIG. 2) within the well. The flow-thru orienting sleeve 400 may include a plurality of flanges 410 , which extend outwardly to increase the effective outer diameter of the shot rod 200 to minimize undesirable contact of the shot rod 200 with components within the well bore. A space 420 is provided between the flanges 410 to permit fluids to pass through the orienting sleeve 400 and along shot rod 200 as the apparatus of the present invention is lowered into place and then removed. The concussive force may then cause the scale or other debris build-up to be dislodged from within the safety valve B.
As will be readily perceived by one skilled in the art, various selections and combinations of explosive length, grain density, gap widths, and other criteria may be made to achieve varying degrees of remediation. Further, repeated application of the explosive forces may be required to remediate certain safety valves. For example, excessive scale or other debris build-up may be present. In such a circumstance, repeated low-level explosive charges may be used to loosen the build-up without damaging the safety valve. It should also be noted that, in a particular embodiment, other forms of detonation and types of charges may also be used to achieve the particular result desired.
It is to be understood that the invention is not limited to the exact details of construction, operation, exact materials or embodiments shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art. Accordingly, the invention is therefore to be limited only by the scope of the appended claims. | In a broad aspect, the invention relates to a method and apparatus for downhole safety valve remediation using a measured, controlled, explosion to remove scale and/or other debris from within or around the downhole safety valve or for explosively locking out the safety valve in an open position. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a division of co-pending U.S. application Ser. No. 12/986,502 filed Jan. 7, 2011, which in turn claims priority to U.S. Provisional App. No. 61/293,354 filed Jan. 8, 2010. Both of said applications are incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
BACKGROUND OF THE DISCLOSURE
[0003] In recent years, various pneumatic grain conveying systems have been employed for conveying grain to and from a grain storage bin or the like. These prior pneumatic grain conveying systems typically employed a positive displacement blower for forcing air into a closed duct or pipe system. Grain to be conveyed was introduced into the piping downstream of the blower by means of a so-called airlock grain inlet or other grain infeed device, which fed the grain into the pipe system in such a manner that the grain was entrained by the air flowing through the pipe system and in such a manner that the pressurized air was not lost thus maintaining the conveying capacity of the pneumatic conveying system. Downstream from the grain inlet the piping system may be directed upwardly, for example, along the sidewall of a grain bin, and along the sloped, conical grain bin roof to a center grain inlet opening in the roof, where a so-called deadhead deflector or a cyclone diffuser was positioned so as to allow the pressurized air to be vented to the atmosphere and to direct the grain into the grain inlet in the grain bin roof. Such pneumatic grain conveying systems have the advantage of moving the grain within a cushion of air that minimizes damage to the grain, as compared to mechanical grain auger conveyors or other types of mechanical grain conveying systems.
[0004] However, such pneumatic grain conveying systems, especially such pneumatic grain conveying systems having high capacity (e.g., 2,500 bushels/hour), require a powerful electric motor (e.g., up to 75 horsepower) for powering the positive displacement blower. Such motors are expensive. It is thus desirable to utilize the same motor and the same airlock grain infeed unit to convey grain to a plurality of grain storage bins. Heretofore, this has been accomplished by providing separate piping systems from the air lock to the various grain storage bins with a complex manifold/distributor, such as shown in FIG. 2 of the instant drawings and as will be hereinafter described, so as to permit the pressurized air duct from the grain infeed airlock to be selectively connected in an air tight fashion to a desired or selected piping system for a selected one of the plurality of grain storage bins. Not only did this prior manner of connecting the pressurized air conveying system to the piping system for a selected grain storage bin require the complex manifold/distributor, but it also required separate piping runs from the grain inlet airlock to each of the grain storage bins with each of these piping runs having a horizontal run along the ground and a vertical run along the vertical sidewall and conical roof of each bin. In turn, this added to the expense and complexity of such prior pneumatic conveying systems. These multiple runs of piping along the ground often interfered with vehicles which require close access to the grain bins. Still further, it has been found that such manifold/distributor systems are sometimes difficult to operate and they often require that the blower and airlock infeed be shut down while making a change from conveying to one bin and then to another bin.
SUMMARY OF THE DISCLOSURE
[0005] A pneumatic conveying system is disclosed for conveying a dry flowable or granular product, such as grain, from a grain inlet device to a selected one of a plurality of grain bins or other storage vessels. The system includes a blower for forcing air under pressure into a conveyor piping system. A grain inlet device is located downstream from the blower. The piping system has a portion leading from the grain inlet to an inlet in a first one of the vessels. A discharge/bypass valve is connected to a portion of the piping system leading from the grain inlet so as to receive the granular product being conveyed therethrough with the valve having a discharge outlet for discharging the granular product into the vessel and a by-pass outlet for by-passing the first vessel and delivering the granular product to a second vessel. The valve is installed on the vessel such that the discharge outlet is in communication with the interior of the vessel. The valve further has an inlet coupling operatively connected to the piping system and an outlet coupling operatively connected to another portion of the piping system downstream of the valve leading to another of the vessels. The valve has a sleeve movable between a discharge position in which the inlet coupling is disconnected from the outlet coupling such that the granular product is discharged from the piping system into the valve and then is discharged into the vessel and a by-pass position in which the inlet and outlet couplings are operatively connected so that the granular product is conveyed through the valve and into the piping system downstream from the valve. The by-pass outlet comprises the outlet coupling.
[0006] In one embodiment, the housing for the valve can be provided with a hopper. The hopper opens into the valve housing below the valve to be in communication with the interior of the vessel. The hopper can receive granular product from an auger, which need not be permanently affixed to the hopper. In this manner, the granular product can be delivered to the vessel via an auger without having to remove the discharge/by-pass valve.
[0007] A method of selectively conveying this granular product to a selected one of the vessels is also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a diagrammatic side elevational view of a typical pneumatic grain conveying system having a positive displacement blower forcing pressurized air into a piping system with an airlock grain infeed downstream from the blower, with a piping system conveying the grain upwardly along the vertical sidewall and along the conical roof of a first grain storage bin (only half of which is illustrated) or other receiving vessel to a so-called grain discharge/by-pass valve of the present disclosure mounted on a center grain inlet in the roof of the first bin, with a reach of piping extending from the outlet of the discharge/by-pass valve to a deadhead deflector mounted on a center grain inlet of a second grain storage bin (again, only one half of the bin is illustrated) or other vessel so that with the discharge/by-pass valve on the first bin in its discharge position grain may be discharged into the first grain bin and so that with the discharge/by-pass valve in its by-pass position grain may by-pass the first bin to be discharged into the second bin;
[0009] FIG. 2 is a perspective view of a prior art manifold/distributor assembly for connecting the pressurized air duct downstream from the airlock grain infeed to a selected one of a plurality of air conveying ducts or piping systems for conveying the grain to a selected one of a plurality of grain storage bins;
[0010] FIG. 3 is a perspective side elevational view of a first embodiment of a discharge/bypass valve of the present disclosure with the valve in a discharge position to discharge grain into the bin on which the valve is mounted;
[0011] FIG. 4 is a perspective view of a portion of the valve shown in FIG. 3 with the exterior housing of the valve removed to better illustrate the components within the housing with these components arranged in a by-pass position so that grain conveyed to the valve will not be discharged into the grain bin on which it is installed but rather will by-pass the grain through the valve into a piping run that will convey the grain to another grain storage bin, with the components of the valve including a rack and pinion linear drive for axially moving a sleeve between a by-pass position (as shown in FIG. 4 ) in which the grain is pneumatically conveyed through the valve and a discharge position, as shown in FIGS. 3 , 5 and 6 , in which grain is discharged into the bin below the valve;
[0012] FIG. 5 is another view of the valve as shown in FIG. 4 with its components arranged in their discharge position with a flapper diverter member disposed at the outlet end of the above-noted sleeve so as to direct grain conveyed through the sleeve downwardly into the bin on which the valve is mounted;
[0013] FIG. 6 is a view similar to FIG. 5 in which the flapper diverter member is raised clear of the end of the sleeve so as to permit the sleeve to be moved axially to be coupled to the piping downstream of the valve when the sleeve is in its by-pass position;
[0014] FIG. 7 is a perspective view of a second embodiment of the valve;
[0015] FIG. 8 is a perspective view of the second embodiment of the valve with portions of the outer housing removed to illustrate internal components, where the above-described flapper diverter member is replaced by curved grain diverter member selectably movable between a discharge position, as shown in FIGS. 8 and 9 , in which, with the sleeve in its above-described by-pass position, grain may flow through the valve to a grain bin downstream from the first bin;
[0016] FIG. 9 is a view similar to FIG. 8 on a somewhat enlarged scale illustrating the axially movable sleeve in its retracted discharge position with the curved grain diverter member in its diverting position;
[0017] FIG. 10 is a view similar to FIG. 9 , on an enlarged scale and with a side wall of the curved grain diverter member removed to better illustrate the curved plate of the diverter member;
[0018] FIG. 11 is a view similar to FIG. 9 with the curved diverter member moved clear of the sleeve and with the sleeve axially extended so as to form a fluid tight (or air-tight) connection between the inlet and outlet couplings so that grain may by-pass the discharge outlet of the bin on which the valve is installed to be delivered to another bin;
[0019] FIG. 12 is a perspective view of a third embodiment of the valve provided with a hopper to enable a bin on which the valve is placed to alternatively be filled by means of a traditional transport auger;
[0020] FIG. 13 is a perspective view of the valve of FIG. 12 , but taken from an opposite side of FIG. 12 ;
[0021] FIG. 14 is a perspective view of the valve of FIG. 12 with portions of the housing removed to show an internal wall of the valve; and
[0022] FIGS. 15 and 16 are cross-sectional views taken along lines 15 - 15 and 16 - 16 , respectively of FIG. 12 , but wherein the curved diverter plate of the valve of FIG. 12 is replaced with an inclined diverter plate.
[0023] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0024] The following detailed description illustrates the claimed invention by way of example and not by way of limitation. This description will clearly enable one skilled in the art to make and use the claimed invention, and describes several embodiments, adaptations, variations, alternatives and uses of the claimed invention, including what we presently believe is the best mode of carrying out the claimed invention. Additionally, it is to be understood that the claimed invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The claimed invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting
[0025] Referring now to the drawings and particularly to FIG. 1 , a pneumatic grain conveying system, as indicated in its entirety at 1 , is shown to be installed on a plurality of grain storage bins or vessels 3 and 5 . Two grain bins 3 and 5 are shown, but those of ordinary skill in the art will understand that additional grain bins can be connected to one another in the manner that bin 3 is connected to bin 5 . As is typical, each of the grain bins has a vertical sidewall 7 , a sloped conical roof 9 , and a grain inlet 11 at the peak of the conical roof.
[0026] The pneumatic grain conveying system 1 includes a motor and blower assembly 13 (preferably a positive displacement blower), which forces pressurized air into a conveyor piping system 15 . The blower and motor are controlled by a control panel 17 . Downstream of the blower, a so-called airlock/grain infeed unit 19 is provided for introducing grain (or other granular, powdered or pulverulent flowable material capable of being pneumatically conveyed) to be introduced into the pressurized air stream moving through piping system 15 . Piping system 15 includes a horizontal run 21 leading to a horizontal-to-vertical elbow 23 , which in turn is connected to a vertical run 25 extending upwardly along the sidewall 7 of the first grain bin. The piping system further includes a sloped run 25 along the conical roof 9 of the first grain bin toward the inlet 11 of the first grain bin.
[0027] A discharge/by-pass valve 27 is installed in register with the grain inlet 11 of the first grain bin. The valve 27 has an inlet 29 coupled to the downstream end of the sloping run 25 and an outlet 31 coupled to pneumatic conveyor tube 33 extending from the valve 27 to a deadhead deflector 35 installed on the grain inlet 11 of the second grain bin 5 . This deadhead deflector 35 allows the pressurized air to escape to the atmosphere thus disrupting the flowing airstream in the conveyor piping run 33 and deflects the grain conveyed through piping run to be discharged into the second grain bin. While not illustrated, it will be understood that in place of the deadhead deflector 35 installed on the grain inlet 11 of the second grain bin, another valve 27 may be installed on the grain inlet of the second bin and another run of piping (not shown) may be connected to the outlet end 31 of this other valve 27 , where this other run of piping leads to the grain inlet 11 of another (i.e., a third) grain bin (not shown) so that grain conveyed to the second bin via the piping run 33 may be selectively discharged into the second bin or may be selective by-passed to the next grain bin. In this manner, the pneumatic conveying system 1 utilizing valves 27 may selectively convey grain to any one of a plurality of grain bins merely by operating the valves 27 installed on the grain inlets 11 of the grain bins upstream of the selected bin to be in their by-pass positions and by operating the valve 27 (or a deadhead valve 35 ) installed on the selected bin in its discharge position. As will become apparent, the discharge/by-pass valves 27 can be operated to selectively alter the bin or vessel in which the grain is to be deposited without the need to shut down the pneumatic conveying system.
[0028] In FIG. 2 , a prior art distributor manifold/selector valve assembly is indicated in its entirety by reference character 201 . The distributor manifold/selector valve 201 includes a frame 203 having a base plate 205 , a head plate 207 , and elongate spacer members 209 extending between the base plate and the head plate. An inlet piping section 211 is adapted to be connected to the pneumatic piping system 15 downstream from airlock grain in feed unit 19 . Preferably, the distributor/manifold assembly 201 is installed adjacent the first grain bin. The head plate 207 has a plurality of manifold ports 213 (six such ports are shown) such that a selected piping run, as indicated at 215 a , 215 b , 215 c , may be operatively connected to the inlet piping section 211 . Each of these last-noted piping runs leads to a respective grain bin so that grain may be selectively conveyed to that grain bin. A selector pipe 217 coupled to the inlet pipe 211 may be selectively coupled to a selected one of the manifold ports 213 , and thus to a selected one of the piping runs 215 a , 215 b or 215 c so as to convey grain to the grain bin corresponding to that piping run.
[0029] Referring now to the valve 27 installed on the first grain bin (as shown in FIG. 1 ), a first embodiment of the valve is illustrated in FIGS. 3-6 . As shown best in FIG. 3 , the valve 27 includes an exterior housing 37 having a top housing panel 39 , side panels 41 , an outlet end plate 43 , an inlet end plate 45 , a bottom plate (not shown in FIGS. 3-6 ), and a bottom hopper discharge chute 47 defining a discharge outlet through which grain is discharged into the grain inlet 11 of the bin supporting the valve 27 . The inlet end plate 45 has an inlet coupling tube 51 adapted to be coupled to the sloped piping reach 25 , and the outlet end plate 43 has an outlet coupling tube 49 adapted to be coupled to piping run 33 . As will become apparent, the outlet coupling tube defines a by-pass outlet of the valve 27 . The inlet coupling tube 51 is rigidly and sealably secured to its inlet plate 45 and the outlet coupling 49 is rigidly and sealably secured to its outlet plate 43 with the inlet and outlet coupling tubes being substantially coaxial with respect to one another and with a space between their inner ends, as shown in FIGS. 5 and 6 . As indicated at 52 a and 52 b , internal support plates support the inner ends of tubes 49 and 51 , respectively, within housing 37 .
[0030] A valve member, shown as a sleeve 53 in the drawings, is axially movable relative to the inlet and outlet coupling tubes 49 and 51 by means of an actuator (a linear actuator as will be hereinafter described), as generally indicated at 55 , as shown in FIGS. 4-6 . The sleeve valve member 53 is movable in an axial direction with respect to the inlet and outlet coupling tubes between a first or by-pass position (more specifically, an extended coupling position as shown in FIG. 4 ) in which grain conveyed to valve 27 will be conveyed through or by-passed through the valve to the next grain storage bin downstream from the bin on which the valve 27 is installed, and a second or discharge position (more specifically, a retracted position as shown in FIGS. 3 , 5 and 6 ). With the sleeve 53 axially uncoupled from inlet coupling tube 51 , the pressurized air within the piping system 15 will be discharged into housing 37 , which is vented to the atmosphere and so that the grain entrained in the air stream flowing through the inlet coupling tube 51 will fall by gravity downwardly into the discharge chute 47 . The linear actuator 55 is also operable so as to axially move the sleeve 53 from its retracted discharge position (as shown in FIGS. 3 , 5 and 6 ) to its extended by-pass position (as shown in FIG. 4 ) in which the sleeve is sealably coupled to the inlet tube 51 . With the sleeve in its by-pass position, the pressurized air stream and the grain entrained therein will be conveyed through the valve 27 and will be conveyed via piping run 33 to the next grain storage bin. Although the sleeve 53 is shown to be moved toward and away from the inlet coupling tube 51 by the actuator 55 , the valve sleeve could alternatively be positioned over the inlet coupling tube, so that the actuator 55 moves the sleeve 53 toward and away from the outlet coupling tube 49 .
[0031] As shown in FIGS. 4-6 , the linear actuator, as generally indicated at 55 , comprises a rack and pinion mechanism having a rack 57 attached to the bottom of sleeve 53 and a pinion 59 journalled on a shaft 61 supported by bearings 63 carried by the housing side walls 41 . The shaft 61 may be selectively rotated by means of a sheave 64 , wheel, or the like attached to one end of the shaft 61 . The sheave may be rotated by any suitable means, such as an electric motor (not shown), or by means of a chain or belt and pulley arrangement (also not shown) that may be manually operated from ground level. Alternatively, the linear actuator may be a fluid cylinder (not shown), such as an air or pneumatic cylinder, that may be remotely actuated so as to move the sleeve 53 between its extended by-pass position and its retracted discharge position. Further, those skilled in the art will recognize that other well known linear actuators, such as a screw drive or the like, may be used. Such linear actuators thus constitute a means for selectively moving the sleeve 53 in an axial direction between its extended by-pass position and its retracted discharge position so that grain may be selectively discharged into the bin below the valve 27 or by-passed to the next bin downstream from the bin on which the valve 27 is installed.
[0032] A block 60 is mounted to the sleeve 53 and a post 62 extends forwardly from the block. The post 62 slides through an alignment hole in the support plate 52 b , to ensure axial alignment of the sleeve 53 with the inlet coupling tube 51 as the sleeve 53 is moved to its extended position in which the sleeve 53 is connected to the inlet coupling tube 51 . The exit end of the inlet coupling tube 51 is tapered to facilitate guiding of the sleeve 53 over the inlet coupling tube when the sleeve is moved to its extended position. The ends of the sleeve 53 can also be tapered.
[0033] The sleeve 53 has an inner diameter greater than the outer diameter of the inlet coupling tube 51 and the outlet coupling tube 49 . The inlet and outlet coupling tubes 51 and 49 are of generally the same inner and outer diameter. The sleeve 53 can thus slide over both the inlet and outlet coupling tubes. The sleeve 53 is provided with internal O-rings 54 at both ends of the sleeve. The O-rings form an air-tight seal between the sleeve 53 and both the inlet and outlet coupling tubes 51 and 49 when the sleeve 53 is in the extended position. This substantially eliminates air (and thus air pressure) loss when the sleeve is in the extended position, to facilitate the transport of the product to the second bin. Although the O-rings are described as being internal O-rings on the sleeve 53 , the O-rings could be external O-rings on the inlet coupling tube and the outlet coupling tube. Any other desired means to form an air-tight seal between the sleeve 53 and the inlet and outlet coupling tubes may also be used. As can be appreciated, the valve 27 provides for an air-tight or pneumatically sealed connection when the sleeve 53 is in its extended position, and an unsealed, atmospheric connection when the sleeve 53 is retracted.
[0034] As further shown in FIGS. 3-6 , a diverter or deflector member 65 , illustratively shown as a flapper or plate, is mounted on a shaft 67 above the sleeve 53 for movement between a raised, retracted position (as shown in FIGS. 4 and 6 ) in which the diverter member is clear of the sleeve and a lowered, diverting position (as shown in FIGS. 3 and 5 ) in which the diverter member 65 is positioned in a discharge space between the retracted sleeve 53 and the outlet end of inlet coupling tube 51 so that grain conveyed through the inlet coupling tube 51 will impinge against the diverter member and be directed downwardly into discharge chute 47 . The diverter member 65 is pivoted from its lowered position to its raised position by the axial movement of the sleeve 53 . That is, as the sleeve 53 is moved axially to its extended by-pass position, the sleeve 53 will engage the diverter member 65 and pivot the diverter member to the raised position. The diverter member 65 is gravity biased toward its lowered, diverting position by means of its own weight, but it will be apparent to one skilled in the art that the movement of the diverter member could be mechanically coupled to the linear actuator to provide a positive engagement and retraction of the diverter. A counterweight 69 can be affixed to one end of the shaft 67 on the exterior of housing 37 . This counterweight also serves as a flag or visual indicator visible from the ground to indicate to an operator whether the sleeve 53 is in its discharge or by-pass position.
[0035] Referring now to FIGS. 7-10 , a second embodiment of the discharge/bypass valve is indicated in its entirety by reference character 27 ′. The valve 27 ′ is similar to valve 27 , as described above, except the flapper diverter member 65 has been replaced by a curved diverter member 71 . The other components of the alternate discharge/bypass valve 27 ′ are similar to the corresponding components of the valve 27 and thus will not be again described. More specifically, the curved diverter member 71 has a curved deflector plate 73 within a diverter housing 75 , as perhaps best shown in FIGS. 10 and 11 . The curved plate 73 could be replaced with a sloped or inclined plate 73 ′ as shown in FIG. 15 or a flat plate. With sleeve 53 in its retracted position clear of the inlet coupling 51 , the diverter housing 75 , which is mounted on shaft 67 for selective rotatary movement about the shaft, is movable between a lowered discharge position (as shown in 8 and 9 ) and a raised position (as shown in FIG. 11 ). In the lowered position, the curved plate 73 is positioned downstream from the inlet coupling tube 51 so that grain discharged from the inlet coupling tube impinges against the curved plate 73 and is directed downwardly into the discharge chute 47 . The diverter housing 75 is also rotatably movable from its above-described lowered discharge position to a raised retracted position (as shown in FIG. 11 ) in which the sleeve 53 may be moved from its retracted discharge position to its extended by-pass position in which it is axially, sealably coupled to inlet coupling tube 51 so that grain may be conveyed through the valve 27 ′ and into piping run 33 to the next grain storage bin. As with the diverter member 65 , the diverter member 71 is pivoted from its lowered position to its raised position by the sleeve 53 . It will be understood that the diverter member 71 may be gravity biased toward its lowered discharge position in the same manner as flapper diverter member 65 , as above described, and likewise may be mechanically coupled to the linear actuator as previously described. Also, it will be understood that when sleeve 53 is axially moved from its retracted discharge position to its by-pass position in which it is in axial coupling engagement with inlet tube 51 , the housing 75 is moved to its retracted position clear of the end of the sleeve. The valve 27 ″ also includes the flag or indicator 69 which is rotationally fixed to the shaft 67 to indicate the position of the diverter member 71 .
[0036] Referring now to FIGS. 12-14 , a third embodiment of the discharge/bypass valve is indicated in its entirety by reference character 27 ″. The valve 27 ″ is substantially the same as the valve 27 ′. The difference between the valves 27 ″ and 27 ′ lies in the housing of the two valves. The housing 37 ″ of the valve 27 ″ is provided with an intermediate section 81 between the discharge chute 47 ″ and the couplings 49 , 51 and the sleeve 53 . This intermediate section 81 is defined by front and back walls 83 a,b and end walls 85 . At least one of the front and back walls, and preferably both of the front and back walls, are provided with an aperture 87 ( FIG. 14 ). With reference to FIGS. 12 and 13 , the aperture of the front wall 83 a is closed by a plate 89 , and the aperture of the back wall 83 b is covered with a side hopper 91 . The hopper 91 opens into the housing 37 ″ below the elements of the valve (i.e., below the inlet and outlet couplings 51 , 49 and the sleeve 53 ). The opening to the hopper 91 is closed by a cover plate 93 . The cover plate 93 can be removed to open the hopper 91 . With the hopper opened, the bin on which the valve 27 ″ is mounted can be filled by means of a traditional auger. In this instance, the outlet of the auger would be just above, or received within, the opening to the hopper 91 . The auger need not be permanently affixed to the hopper 91 . The cover plate 93 is shown to be secured to the hopper by means of bolts, which would need to be removed to open the hopper for use. The hopper cover 93 can be hinged to the frame of the hopper, such that the cover 93 can be opened and closed either from ground level. The provision of the aperture 87 on both the front and back walls 83 a,b allows for the hopper to be mounted to either the front or the back wall. It also allows for the hopper to be moved from the front to the back wall, should that be desired. Additionally, if desired, a hopper 91 could be mounted to both the front and back walls.
[0037] With reference to FIG. 14 , the intermediate section 81 is provided with a vertical internal plate 95 . The internal plate 95 is positioned to be generally flush with the inlet of the outlet coupling (and the end of the sleeve 53 when in the retracted position). In this way, the plate 95 will keep grain away from the linear actuator (i.e., the rack and pinion).
[0038] With reference to FIGS. 12 and 14 , the sheave 64 is mounted to the shaft 61 ″ by means of a bolt 97 which passes through a passage in the shaft 61 ″. The opposite end of the shaft 61 ″ includes a corresponding passage. This allows for the sheave 64 to be positioned on either side of the valve housing 37 ″, or to be moved from one side to the other. Similarly, the counterweight 69 , which serves as an indicator flag, can be mounted on either side of the housing, or moved from one side of the housing to the other.
[0039] The diverter members 65 and 71 are described to be moved from their lowered positions to their raised positions by the sleeve 53 as the sleeve moves to its by-pass position. However, the diverter members could be connected, for example by way of linkages, to the linear actuator, such that the diverter member is directly moved by the linear actuator.
[0040] It will be recognized that regardless of the embodiment of the valve 27 , 27 ′, or 27 ″ that is utilized, the valve may be operated by its linear actuator 55 from the ground level without the necessity of shutting down the blower 13 . This aids in switching the discharge of grain from one bin to another.
[0041] While the valves 27 and 27 ′ of the present disclosure have been described in the environment of conveying grain to grain storage bins, those of ordinary skill in the art will appreciate that the air conveying system 1 may be used to convey other particulate or granular, fluent materials, such as powered materials or plastic pellets or the like that are capable of being pneumatically conveyed. Additionally, it will be appreciated that the grain storage bins may be any desired vessel for receiving the particulate or powdered material.
[0042] Still further, those of ordinary skill in the art will recognize that the slidable sleeve 53 type diverter valve may be replaced with other types of diverter valves. For example, a rotary diverter valve, such as shown in U.S. Pat. No. 5,070,910 may be used to divert the flow of grain within valve 27 between a discharge position and a by-pass position. Further, a flapper-type diverter valve, such as shown in FIGS. 7-8B of U.S. Pat. No. 6,964,544 may also be used to divert the flow of grain within valve 27 between a discharge position and a by-pass position. U.S. Pat. Nos. 5,070,910 and 6,964,544 are herein incorporated by reference in their entirety. But neither of the above referenced valves provides a pneumatically sealed connection in only one selectable position and an unsealed, atmospheric connection in another selectable position. For the valves of the two referenced patents to work according to the valves 27 , 27 ′ or 27 ″, the valves would have to be modified such that in a first position, the path between the inlet and a first outlet is sealed (i.e., air tight), and such that in a second position, the valve inlet is open to the atmosphere.
[0043] As various changes could be made in the above constructions without departing from the broad scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | A pneumatic conveying system is disclosed for conveying a granular product, such as grain, from a grain inlet device to a selected one of a plurality of grain bins or other storage vessels. The system includes a blower for forcing air under pressure into a conveyor piping system. A grain inlet device is located downstream from the blower. The piping system has a portion leading from the grain inlet to an inlet in a first one of the vessels. A discharge/bypass valve is connected to a portion of the piping system leading from the grain inlet so as to receive the granular product being conveyed therethrough with the valve having a discharge outlet for discharging the granular product into the vessel. The valve is installed on the vessel such that the discharge outlet is in communication with the interior of the vessel. The valve further has an inlet coupling operatively connected to the piping system and an outlet coupling operatively connected to another portion of the piping system downstream of the valve leading to another of the vessels. The valve has a sleeve movable between a discharge position in which the inlet coupling is disconnected from the outlet coupling such that the granular product is discharged from the piping system into the valve and then is discharged into the vessel and a by-pass position in which the inlet and outlet couplings are operatively connected so that the granular product is conveyed through the valve and into the piping system downstream from the valve. | 8 |
[0001] The present invention relates to a prosthetic openwork knit for the treatment of urinary incontinence and/or prolapse, particularly for producing bands or tapes for urethral support in the treatment of female stress incontinence, and the treatment of what are generally mainly female pelvic floor disorders, also known as prolapse.
BACKGROUND OF THE INVENTION
[0002] The surgical treatment of female stress incontinence usually involves the use of reinforcements in the form of tapes placed underneath the middle urethra. The central part of the implant is placed below this organ and may be in contact with it in order to support it while the lateral parts of the implant are attached to stable anatomic parts such as the abdominal wall, the posterior face of the OS pubis, or the obturator membrane, for example by means of staples, sutures or simple tissue anchoring.
[0003] As far as the treatment of prolapse is concerned, part of the implant is positioned against or near the organ to be supported and part against stable anatomic parts such as the abdominal wall, the posterior face of the OS pubis, the obturator membrane, the promontory of the sacrum, or the sacrosciatic ligaments, for example by means of staples, sutures or simple tissue anchoring.
[0004] As is known, such a support implant must satisfy many demands, and in particular must have appropriate mechanical strength, particularly in the longitudinal direction, and be biocompatible and flexible. These support implants must also be macroporous so as to integrate intimately and quickly into the receiver's tissues without interfering with the hollow viscera with which they are in contact when implanted. These implants are advantageously made from biocompatible monofilament in order to develop the least possible surface area that could encourage bacterial colonization. These support implants may be suturable. The implants may also advantageously be relatively inextensible longitudinally so that they can easily be pulled along sometimes tortuous anatomical paths. Lastly, it is desirable that these support implants be adapted to the anatomy and morphology of the patient in both breadth and length.
DESCRIPTION OF THE PRIOR ART
[0005] One essential property of these implants is their mechanical strength, which must be very great in order to support the organs to be treated. To increase this strength, it has been proposed that the amount of material used in the implants be increased, as by using thicker and therefore stronger yarns, or by making a denser lattice.
[0006] However, since such implants are designed to be left permanently in the patient's body, it is undesirable to increase the amount of material used in these treatments, such being contrary to present-day criteria of tolerance and of tissue integration of support and reinforcement implants.
[0007] Another problem that occurs with support tapes is their curling. For the purposes of the present application, “curling” means the spontaneous rolling up of the tape upon itself, about its longitudinal axis, when stretched in the direction of its length. In this form, these implants must maintain adequate mechanical (particularly strength) properties while minimizing the release of particles, that is ends of yarns when under stress and must allow mechanically stable tissue anchoring.
[0008] There is therefore a need for a knit, especially one that is macroporous and made from monofilament, that can be used to produce support implants, particularly in the form of tapes, having both excellent mechanical strength and the least possible mass per unit area.
[0009] It is an object of the present invention to fulfill this need by providing a knit having a particular arrangement of yarns, in particular having at least one meshing sheet and at least two non-meshing sheets, making it possible to produce support tapes that have great mechanical strength and are very lightweight and stable.
SUMMARY OF THE INVENTION
[0010] The present invention relates to a prosthetic openwork knit for the treatment of urinary incontinence and/or prolapse, based on an arrangement of yarns of a biocompatible polymer comprising at least one first sheet defining a first chain structure, in which knit said arrangement of yarns further comprises at least two non-meshing sheets, of partial weft, the number of chain yarns in said chain structure being from 6 to 12.
[0011] The present invention also relates to the use of a prosthetic knit as above to obtain a prosthetic product for surgical use, particularly to obtain a support implant for the treatment of stress urinary incontinence and/or prolapse.
[0012] The knit according to the invention can be used directly as a support implant for the treatment of stress urinary incontinence and/or prolapse or may be cut up transversely to obtain such an implant.
[0013] The invention also relates to a support implant for the treatment of stress urinary incontinence and/or prolapse, which is obtained by cutting transversely a prosthetic knit as above.
[0014] The present invention also relates to a method of producing a prosthetic openwork knit as above that comprises the following steps:
a) a knitted structure is produced on a warp or Raschel machine as a first sheet threaded continuously or as needed and obtained from a first guide bar, the chart followed for the knitting of the yarns of said first sheet leading to the formation of a chain, and at least a first non-meshing sheet and a second non-meshing sheet, said non-meshing sheets being threaded continuously or as needed, each said non-meshing sheet being obtained from a guide bar, the chart followed for the knitting of the yarns of each non-meshing sheet being such that for every n yarns (A) of the chain structure, n ranging from 6 to 12, every yarn of said non-meshing sheets that approaches chain yarn n+1 (A 1 , A 11 , A 12 ) turns back one hundred and eighty degrees at said chain yarn n+1, said chain yarn n+1 being termed the free chain yarn, and b) said free chain yarns are unroved along the length of the knitted structure obtained in step a) and said free chain yarns are removed to produce knits in which the number of chain yarns is from 6 to 12.
[0017] The knit or implant according to the invention has excellent mechanical strength, in particular an excellent tensile strength, can be relatively inelastic, and is therefore ideal for producing a support implant for the treatment of stress urinary incontinence and prolapse, without the use of a protective sheath being necessary.
[0018] Moreover, because of the specific arrangement of yarns which it comprises, particularly due to the presence of two non-meshing sheets, the knit or implant according to the invention is very light, yet has sufficient mechanical strength to support the organs to be treated. Thus, the knit or implant according to the invention includes a minimal amount of yarn and therefore of material but is nevertheless strong enough to support the organs to be treated.
[0019] In particular, the presence of two non-meshing sheets, generally two intersecting non-meshing sheets, i.e. their respective guide bars move symmetrically with respect to each other and are offset one with respect to the other in the direction of production of the knitted structure on the knitting machine, makes it possible to obtain knits and/or tapes and/or implants that have good resistance to lateral compression. Consequently, when the two opposite longitudinal edges of a knit, tape and/or implant according to the invention, obtained from said knitted structure, are compressed, for example between two fingers, this knit, tape and/or implant retains roughly the same width. The loss of width of a knit, tape and/or implant according to the invention when its two opposite longitudinal edges are squeezed between two fingers is preferably less than 10%. The knit, tape and/or implant according to the invention therefore has great stability during manipulation, passage through any auxiliary equipment (the eye of a needle, a canula or the like) and in the tissues of the patient (limiting the string effect).
[0020] Owing to its particular arrangement of yarns, there is therefore no risk of unroving of the knit, tape and/or implant according to the invention.
[0021] Again, owing to its method of production, this knit has edges that are atraumatic and stable, meaning that it will not fray or release particles and can therefore be introduced into the tissues without a protective sheath. In addition, all the knits, tapes or implants obtained from one knitted structure have uniform heat-setting and are easy to handle.
[0022] In the present application the expression “prosthetic knit” means a knit designed to be implanted into a human or animal in the form of a prosthesis or in the form of any other articles fashioned at least partly with said knit.
[0023] In the present application the expression “openwork knit” means a knit whose structure or structures create cells or holes through the thickness of the knit, and these cells or holes can act as channels leading from one side of the knit to the other. Such an openwork (or “macroporous”) knit will integrate better into the tissues.
[0024] The expression “meshing sheet” means, in the present application, a sheet of yarns in which the chart followed for the knitting of the yarns leads to the formation of meshes. As is known, a chain-structured sheet is a meshing sheet, whereas sheets with partial weft are non-meshing sheets.
[0025] In the present application the expression “free chain yarn” means a chain yarn with no weft yarn completely passing through it, in other words a chain yarn in which, all the way along the longitudinal dimension of the knitted structure, any weft yarn approaching and interacting with this chain yarn, for example by being linked to it, then turns back one hundred and eighty degrees on reaching this chain yarn.
[0026] In the present application,
the mass per unit area of a knit is measured in accordance with standard ISO 3801, the tensile strength of a knit in the longitudinal direction and in the transverse direction is measured in accordance with standard ISO 13934-1, and the elongation under 2 daN in the longitudinal dimension is measured in accordance with standard ISO 13934-1.
[0030] Preferably the number of chain yarns in the knit according to the invention is from 8 to 11, and is preferably 9. With about this number of chain yarns it is possible to obtain a knit that has good mechanical strength in the length direction and good longitudinal and transverse stability.
[0031] The knit is preferably based on monofilament or multifilament yarns of a biocompatible polymer material selected from polypropylene, polyester, polyamide and blends thereof. Said biocompatible polymer is advantageously polypropylene.
[0032] In another embodiment, the knit according to the invention is based on monofilament or multifilament yarns of a biocompatible and bioresorbable polymer.
[0033] In yet another embodiment, the knit according to the invention can be made from a blend of bioresorbable biocompatible yarns and non-bioresorbable biocompatible yarns. It is thus possible to make temporarily reinforced implants whose skeleton must remain permanently inside the patient's body for a permanent minimal support.
[0034] The knit according to the invention is preferably based on monofilament yarns having a diameter of from 0.05 mm to 0.15 mm, preferably approximately 0.10 mm.
[0035] With such a diameter, associated with the particular arrangement of yarns of the knit according to the invention, it is possible to achieve excellent mechanical strength without having to add to the amount of material by using thick yarns.
[0036] The knit according to the invention preferably has a thickness of from 0.20 mm to 0.40 mm, preferably approximately 0.30 mm.
[0037] In a preferred embodiment of the invention, the knit comprises cells having a diameter of from 0.3 to 1.5 mm, preferably of from 0.3 to 0.9 mm. With such a structure there is improved tissue anchoring.
[0038] The knit according to the invention preferably has a width of from 0.6 cm to 1.5 cm.
[0039] The knit according to the invention preferably has a mass per unit area which is from 40 to 75 g/m 2 , and is preferably from 50 to 60 g/m 2 .
[0040] Advantageously, the tensile strength of the knit according to the invention in the longitudinal and transverse directions, measured according to standard ISO 13934-1 is from 20 to 90 N, preferably from 40 to 90 N, preferably from 55 to 75 N, and more preferably from 60 to 70 N.
[0041] The knit or implant according to the invention therefore combines excellent mechanical strength, or tensile strength, with a small mass per unit area, while being relatively inelastic and insensitive to the modifications associated with the conditions of use such as curling, stringing or deformations in the transverse direction, and release of particles. An implant of this kind is advantageous because it can be used to give efficient support to the organs to be treated while minimizing the mass of the implanted foreign body.
[0042] The knit according to the invention preferably has an extension under 2 daN in the longitudinal direction, measured according to standard ISO 13934-1, of less than or equal to 15%, more preferably less than or equal to 10%.
[0043] The knit according to the invention preferably comprises a first non-meshing sheet and a second non-meshing sheet, said first non-meshing sheet being in accordance with the chart 1-1/3-3/2-2/0-0//, said second non-meshing sheet being in accordance with the chart 3-3/2-2/0-0/1-1//.
[0044] Such charts are highly advantageous because they keep the chain yarns better in position, have excellent transverse and longitudinal mechanical strength, and keep the cells as large as possible, without adding material.
[0045] In an embodiment of the invention, the knit according to the invention has a number of stitch courses per centimeter ranging from 13 to 18. Preferably, this number of stitch courses per centimeter is 15. Such a number of stitch courses per centimeter allows a better holding and a better fixing of the knitted structure. The knit according to the invention is not loose and is quite dense.
[0046] The knit according to the invention is preferably heat-set.
[0047] In one embodiment of the invention, the knit according to the invention has a length of from 10 to 50 cm and constitutes a support implant for the treatment of stress urinary incontinence and/or prolapse.
[0048] In another embodiment of the invention, an implant according to the invention is made by cutting the knit according to the invention in the transverse direction. The implant according to the invention preferably has a length of from 10 to 50 cm.
[0049] The knit according to the invention is preferably produced by a method comprising the following steps:
a) a knitted structure is produced on a warp or Raschel machine as a first sheet threaded continuously or as needed and obtained from a first guide bar, the chart followed for the knitting of the yarns of said first sheet leading to the formation of a chain, and at least a first non-meshing sheet and a second non-meshing sheet, said non-meshing sheets being threaded continuously or as needed, each said non-meshing sheet being obtained from a guide bar, the chart followed for the knitting of the yarns of each non-meshing sheet being such that for every n yarns (A) of the chain structure, n of from 6 to 12, every yarn of said non-meshing sheets that approaches chain yarn n+1 (A 1 , A 11 , A 12 ) turns back one hundred and eighty degrees at said chain yarn n+1, said chain yarn n+1 being termed the free chain yarn, and b) said free chain yarns are unroved along the length of the knitted structure obtained in step a) and said free chain yarns are removed to produce knits in which the number of chain yarns is from 6 to 12.
[0052] Therefore, according to the method of manufacturing the knit according to the invention, all the chain yarns, be they free or not, are knitted with the same guide bar.
[0053] The value n is preferably from 8 to 11 and, more preferably, n is 9.
[0054] In a preferred embodiment of the method according to the invention, the yarns of the first chain-structured sheet are knitted in accordance with a chart 1-0/0-1//, the yarns of the first non-meshing sheet are knitted in accordance with a chart 1-1/3-3/2-2/0-0//, and the yarns of the second non-meshing sheet are knitted in accordance with a chart 3-3/2-2/0-0/1-1//.
[0055] Preferably, the guide bar of the first chain-structured sheet is continuously full-threaded, the guide bar of the first non-meshing sheet is threaded continuously 1 full, 1 empty, 3 full, 1 empty, 1 full, 3 empty, and the guide bar of the second non-meshing sheet is threaded continuously 1 full, 1 empty.
[0056] The two guide bars of the two non-meshing sheets advantageously move in partial weft under three needles, symmetrically with respect to each other, each offset with respect to the other in the direction of production of the knitted structure. Such a knitting pattern, with the weft bars moving symmetrically with respect to each other and therefore intersecting each other, holds the chains more securely and therefore has better resistance to lateral compression of the knits, implants and/or tapes according to the invention obtained from this knitted structure.
[0057] The knitted structure preferably undergoes heat-setting between step a) and step b). The knitted structure is thus easy to manipulate, particularly in the unroving step. Also, all knits and implants according to the invention obtained from any one heat-set knitted structure have uniform heat-setting, which ensures better uniformity of the physical and mechanical properties from one tape to the next following unroving.
BRIEF DESCRIPTION OF THE DRAWINGS
[0058] A clearer understanding of the invention will be gained from the description which follows with reference to the accompanying drawings:
[0059] FIG. 1 is a simplified diagram of a knitted structure comprising a first sheet of chain structure and two non-meshing sheets from which the knit according to the invention can be obtained;
[0060] FIG. 2 shows a knitted structure from which the knits according to the invention can be obtained, from which two free chain yarns have been partially unroved;
[0061] FIG. 3 is the drawing of a view under an Itashi S 800 scanning electron microscope, enlarged 20×, of the unroving of a free chain yarn from a knitted structure, enabling knits according to the invention to be obtained;
[0062] FIG. 4 is the drawing of a view under an Itashi S 800 scanning electron microscope, enlarged 20×, of the center of a knit or implant according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0063] In FIG. 1 , E-E′ shows, for a knitted structure from which a knit according to the invention can be obtained, the transverse direction or dimension of the knit; F-F′ the longitudinal direction or dimension of the knit; and G-G′ the diagonal direction or dimension of the knit.
[0064] This figure shows the movements of the chain yarns and weft yarns for a knitted structure from which a knit according to the invention can be obtained, having a chain sheet and two non-meshing sheets. Yarns A and A 1 of the chain structure are shown in thick solid lines. Yarn A 1 is a free chain yarn within the meaning of the present invention. The yarns of the first non-meshing sheet are shown in thin solid lines: these are the B yarns. The yarns of the second non-meshing sheet are shown in broken line: these are the C yarns.
[0065] In this example, the first guide bar, corresponding to the chain structure, is continuously full-threaded. The second guide bar, corresponding to the first non-meshing sheet and to the B yarns, is threaded continuously 1 full, 1 empty, 3 full, 1 empty, 1 full, 3 empty. The third guide bar, corresponding to the second non-meshing sheet and to the C yarns, is continuously threaded 1 full, 1 empty.
[0066] The knitting charts for these three sheets are as follows:
the chain sheet (yarns A and A 1 ): 1-0/0-1//; the first non-meshing sheet (B yarns): 1-1/3-3/2-2/0-0//; the second non-meshing sheet (C yarns): 3-3/2-2/0-0/1-1//.
[0070] Thus, as FIG. 1 shows, no weft yarn passes all the way through chain yarn A 1 ; in other words, each weft yarn, that is any B or C yarn, approaching said chain yarn A 1 , is optionally linked with said chain yarn A 1 , and then turns back one hundred and eighty degrees at this chain yarn A 1 .
[0071] The free chain yarn A 1 can thus be unroved without affecting the adjacent chain yarns A, which are not free within the meaning of the present application, and therefore without destroying the structure of the knit on either side of this yarn A 1 . When this chain yarn A 1 is pulled, the part of the knit lying on the left of this yarn A 1 separates from the part lying on the right of this yarn A 1 without unroving these two parts.
[0072] Moreover, because any weft yarn that approaches yarn A 1 turns back one hundred and eighty degrees at this yarn A 1 , the edges of the separated parts have only one yarn B or C turning back through one hundred and eighty degrees and they are therefore smooth. No fraying occurs.
[0073] Such unroving of a free chain yarn A 1 from a knitted structure from which a knit according to the invention can be obtained is visible in FIG. 3 , which is the drawing of a photograph, taken with an Itashi S 800 scanning electron microscope, enlarge 20×, of an unroved part of such a knitted structure according to FIG. 1 and Example 1 of the present application. At the top of the figure, yarn A 1 is unroved and the knitted parts on either side of this yarn A 1 are intact. Their edges are smooth, only a C yarn does a one hundred and eighty degree turn. No yarn of the knit is cut or fraying. As appears clearly from FIG. 3 , thanks to the specific threading of the yarns of the non-meshing sheets, the yarn C doing a one hundred and eighty degree turn at the edge of a separated part is integral with the core of said separated part, that is to say with the knit according to the invention. In this figure, yarn A 1 is in the process of being unroved. Hence, at the bottom of the figure, yarn A 1 is still knitted to the C yarns approaching it.
[0074] When unroving is complete, that is to say, when yarn A 1 has been unroved all the way down the length of the knitted structure, yarn A 1 is removed from said knitted structure and the two knitted parts lying on either side of this yarn A 1 are completely separated. Repeating this unroving process on a second free chain yarn will completely separate a band from said knitted structure, this band being the knit according to the invention. The distribution of the A 1 yarns predetermines with great precision the width of each tape.
[0075] FIG. 2 shows diagrammatically a knitted structure 2 from which knits 1 according to the invention can be obtained. Two of the free chain yarns, yarns All and A 12 , are partially unroved. Complete unroving of these free chain yarns A 11 and A 12 thus produces a knit 1 according to the invention, that is a tape that can be used in the treatment of female stress urinary incontinence. Such tapes can also be used in the treatment of prolapse.
[0076] The center of a knit, tape or implant according to the invention is shown in FIG. 4 , which is the drawing of a photograph taken under an Itashi S 800 scanning electron microscope, enlarged 20×. The knit or implant according to the invention corresponds to an area of said knitted structure 2 between two consecutive free chain yarns. The knit or implant does not therefore itself include any free chain yarns. There is therefore no risk of it unroving.
EXAMPLE
[0077] A knitted structure from which a knit according to the invention can be obtained was made from 0.10 mm-diameter polypropylene monofilament yarn on a Raschel machine, with one chain sheet and two non-meshing sheets, in accordance with the following charts for the different sheets:
the chain sheet: 1-0/0-1//; the first non-meshing sheet: 1-1/3-3/2-2/0-0//; the second non-meshing sheet: 3-3/2-2/0-0/1-1// .
[0081] The first guide bar, corresponding to the chain structure, was continuously full-threaded. The second guide-bar, corresponding to the first non-meshing sheet, of partial weft, was continuously threaded 1 full, 1 empty, 3 full, 1 empty, 1 full, 3 empty. The third guide bar, corresponding to the second non-meshing sheet, of partial weft, was continuously threaded 1 full, 1 empty. The two partial wefts were threaded in such a way as to move under nine chain yarns, this making it possible eventually to obtain separate tapes, each about 1 cm wide. Thus, in this example, 1 chain yarn out of 10 was a free chain yarn within the meaning of the invention. The gage used was 24 needles.
[0082] The guide bars of the two non-meshing sheets moved in partial weft under three needles, symmetrically to each other, offset from each other in the direction of production of the knitted structure.
[0083] This knitted structure corresponds to the structure shown in FIG. 1 of the present application.
[0084] As it came off the machine, the knitted structure went through a heat-setting operation.
[0085] From this knitted structure, knits or tapes were produced by unroving at least two consecutive free chain yarns. The knits or tapes had the following characteristics:
thickness: approximately 0.3 mm; diameter of cells: approximately 1 mm; width: approximately 1 cm; mass per unit area: approximately 50 g/m 2 ; tensile strength measured in accordance with method ISO 13934-1 on a tape 1 cm wide by 20 cm long: 66 N.
[0091] The knit or tape produced in this way by unroving at least two preferably consecutive free chain yarns from said knitted structure exhibits excellent tensile strength and is thus highly suitable for use as, or for the production of, a support implant for the treatment of stress urinary incontinence and prolapse.
[0092] For example, an implant having a length of 20 cm, or 30 cm or indeed 40 cm can be prepared from this tape. Such an implant has a very low mass per unit area. The amount of material implanted into the patient's body is therefore minimal.
[0093] Furthermore, owing to its method of manufacture, this implant has little elasticity and its edges, particular its longitudinal edges, are atraumatic, which means that it can be implanted without a protective sheath. Also, all knits, tape or implants obtained from the same knitted structure have uniform heat-setting and are easy to manipulate. | The present invention relates to a prosthetic openwork knit for the treatment of urinary incontinence and/or prolapse, based on an arrangement of yarns of a biocompatible polymer comprising at least one first sheet defining a first chain structure, in which knit said arrangement of yams further comprises at least two non-meshing sheets, of partial weft, the number of chain yarns in said chain structure being from 6 to 12. The invention also relates to a support implant for the treatment of stress urinary incontinence and/or prolapse obtained from this knit, and to the method of producing such a knit. | 3 |
This application is a continuation of application Ser. No. 08/036,270, filed Mar. 24, 1993 (abandoned).
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for operating a gas turbine group.
2. Discussion of Background
In a thermal power station installation, in particular an air storage installation, particular problems can arise with respect to the turbine cooling. These occur because of the very high pressure ratios of approximately 30:1 to 70:1 necessary for compatibility with an economically tolerable compressed-air reservoir. This very high pressure ratio demands, again for economic reasons, at least one reheat stage in the turbine expansion. The heat or temperature drop for the high-pressure turbine, referred to below as the HP turbine, is then substantially smaller than that of the low-pressure turbine, referred to below as the LP turbine. In an air storage gas turbine, in which the compressor is equipped with an intercooling system, compressed air is delivered to a storage cavern by the electrical machine, operated as a motor. An air/water heat exchanger cools the heated compressed air coming from the last compressor unit for the purpose of reducing its specific volume and transfers the heat into a pressurized-water accumulator installation, the corresponding shut-off elements being open during this so-called charge operation.
If electrical energy now has to be generated from the stored compressed air, the compressor group is shut down by means of a control system. The turbine group which, for example, comprises an HP turbine, an LP turbine and the electrical machine, now operated as a generator, is started by opening the corresponding closing element. This takes place initially simply by means of compressed air from the reservoir, which compressed air is preheated in the heat exchanger by the stored hot water. The production of electrical energy can be undertaken after ignition in the combustion chamber. It is, however, also possible to let the installation operate as a through-connected gas turbine by appropriate disposition of the shut-off elements and couplings. It is then possible to store some air at the same time or to extract some from the cavern.
Such an installation can no longer meet the present-day economic specifications with respect to reducing the fuel consumption and the position is aggravated by the fact that such installations are not in a position to satisfy the maximum pollutant emission figures which now have to be demonstrated. It is, in fact, correct that a waste heat boiler can be added for generating steam. The steam generated in this way can be supplied to a steam turbine group or it is directly supplied to the gas turbine group in accordance with known methods. The question of whether one or the other method of utilizing the steam is preferred depends on the duration of the turbine operation. Steam injection is correct for less than approximately 2-4 hours per day.
If such a thermal power station installation is now optimized, the hot gas temperatures corresponding to the prior art at inlet to the HP turbine produce such a high outlet temperature of the combustion gases from the HP turbine that these gases cannot be used directly as coolant for the LP turbine. For this reason, the turbine is usually cooled by cooling air which is extracted before the cavern of the air storage installation, as is usual for the cooling of turbines. In through-connected gas turbine operation, it is of course possible to avoid throttling losses by extracting the cooling air leading to the turbine at a compressor location which is appropriate with respect to pressure. Whereas, for a given mixed temperature at inlet to the turbine, the consumption of cooling air for the turbine reduces the turbine efficiency mainly because of mixing losses, the consumption of cooling air for the LP turbine has very disadvantageous effects because this cooling air bypasses the HP turbine and, therefore, does no work in it.
SUMMARY OF THE INVENTION
Accordingly, one object of this invention, as claimed in the claims, is to propose measures, in a method of the type quoted at the beginning, which introduce an improvement in the economy and minimize the pollutant emissions by cooling one or a plurality of structures in the gas turbine group and can, in consequence, obviate the disadvantages presented above.
The essential advantage of the invention may be seen in the fact that the cooling of the structures, for example the heat generator at the low-pressure end, the LP turbine, etc takes place by means of a certain quantity of exhaust gases from the HP turbine, this partial gas flow being preferably led through a heat exchanger before it is used, there being a flow of cooling air from the gas turbine group or from the air storage installation through this heat exchanger.
Furthermore, there is no difficulty about activating a steam quantity from the steam cycle as the cooling medium for the heat exchanger.
A further possibility consists in effecting the cooling of the partial gas flow directly by spraying in water and/or steam.
A further advantage of the invention may be seen in the fact that the partial gas flow can flow through the gas turbine group structures to be cooled in parallel or in series.
Advantageous and expedient further developments of the solution to the object of the invention are claimed in the further claims.
BRIEF DESCRIPTION OF THE DRAWING
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing, wherein the single FIGURE shows a circuit by means of which the cooling of the LP turbine is effected by means of exhaust gases from the HP turbine.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawing, the FIGURE shows an air storage gas turbine comprising a gas turbine group 32, an air storage installation 34 and a steam cycle 33, in which the exhaust gases from the gas turbine group 32 are thermally utilized in the manner of a combined installation. A compressor group, in the gas turbine group 32, comprising a first compressor 1a, a second compressor 1b and an intercooler 2 connected between them, compresses the induced air 3 and delivers it via a conduit 4 into a cavern 5 of the air storage installation 34. This delivery of the compressed air to the cavern 5 takes place via a further conduit 6 which branches off from the first conduit 4. The conduit 4 is also the delivery line to a first heat generator 7 of the gas turbine group 32, a series of actuating elements undertaking the operational interconnection of the conduits 4, 6.
The conduit 6 to the cavern 5 has, firstly, an actuating element 8 immediately after it branches from the conduit 4, two further actuating elements 9, 10 upstream and downstream of the same ensuring that the respective conduit can be switched on. Delivery of the compressed air to the cavern 5 takes place when the first actuating element 9 in the conduit 4 and the actuating element 8 in the conduit 6 are open whereas the second actuating element 10 in the conduit 4 remains closed. The installation is through-connected and operated as a pure gas turbine group by closing the actuating element 8 in the conduit 6 and simultaneously opening the two actuating elements 9, 10.
A heat exchanger 11, which is connected to a heat accumulator 13 via a conduit system 12, acts downstream of the actuating element 8 in the conduit 6 to the cavern 5. This accumulator 13 accepts the compression enthalpy of the last compressor stage 1b, the compressor being driven by the electrical machine 14, operating as a motor and the energy to be stored being therefore drawn from the electrical grid. The compression enthalpy contained in the heat accumulator 13 is re-supplied to the cold storage air during discharge operation so that the work capacity of the cold storage air increases.
It has been found that further raising the temperature of the working medium by means of a heat generator, perhaps operated with a gaseous fuel, increases the work capacity by a further significant amount. This is of great economic advantage because the additional investment is small compared with the gain in work. This is the only possible way of operating an air storage power station profitably. Account must also, however, be taken of the fact that the air pressure must be set as high as possible in order to keep the costs of the cavern 5 as low as possible; 50 to 70 bar is the rule. Such a high pressure, however, favors the occurrence of NO x in the first heat generator 7 upstream of an HP turbine 15 to which these hot gases are to be admitted. This is not permissible from the ecological point of view. Help can be provided by appropriate means, such as spraying in ammonia at a suitable location.
What does have to be provided, on the other hand, relates to the cooling of the thermally loaded units the gas turbine group 32. The figure shows a circuit in which the cooling of the LP turbine 19 takes place by means of exhaust gases from the HP turbine 15. A partial gas flow is taken from the HP turbine 15 at an appropriate extraction location 16 via a cooling gas conduit 17 and is led to a heat exchanger 20. The remaining, major exhaust gas flow from the HP turbine 15 is led into a further downstream heat generator 18 in which this exhaust gas is again thermally prepared before it is admitted to the LP turbine 19. The heat exchanger 20 mentioned acts in the air conduit 4, the exhaust gas flow 17, which is much too hot for cooling purposes, being cooled by heat exchange with the relatively cold compressed air 4. The heat exchanger 20 can also, of course, be located in a partial flow of the air conduit 4, which partial flow is then appropriately more strongly heated. This relatively strongly preheated working air can then be introduced at an appropriate location into the heat generator 7 at the high-pressure end via a conduit, which is not represented. Account has then to be taken of the fact that the air flowing through the conduit 4 has relatively low temperatures.
The heat exchanger 20 can be operated with a relatively cold air mass flow both in through-connected operation of the gas turbine group 32 and in discharge operation of the air storage installation 34. In through-connected operation of the gas turbine group 32, the intercooling in the compressor group, by the intercooler 2, ensures that the temperature level remains low. In discharge operation of the air storage installation 34, a temperature level of approximately 200° C. is present, which lies substantially below the usual cooling air temperature level of 360°-400° C.
In order to increase the pressure drop of the cooling flow, the partial cooling gas quantity 17, which is extracted from the HP turbine 15 for purposes of cooling the various structures of the gas turbine group, is preferably extracted before the end of expansion of the turbine 15, as is symbolized by the tapping conduit 27.
The structures mentioned can be connected in parallel or in series, depending on the degree of thermal loading and the cooling potential of the partial cooling gas quantity 17. In the case of parallel connection, the partial cooling gas flow 23 is divided, for example after the booster fan 26, into two flows of which one flows through the LP turbine 19 for cooling purposes and the other flow 23a flows through the heat generator 18 at the low-pressure end. In this configuration, the actuating element 10b upstream of the LP turbine 19 is open whereas the other actuating element 10a, downstream of the heat generator 18, is closed. In the case of series connection, the actuating element 10b is closed. The whole of the partial cooling gas flow 23 flows to the heat generator 18 via the conduit 23a and subsequently to the LP turbine 19 via a further conduit 23b. It is clear that in the configuration last mentioned, the actuating element 10a downstream of the heat generator 18 is open.
Furthermore, it is obvious that the cooling technique in the heat generator 18 depends on the type of cooling used for the structures, i.e. whether the cooling is carried out in parallel or in series. The pressure drops of this partial cooling gas flow can also be achieved by means of a booster fan 26 which is placed somewhere in the supply 23 of the cooled exhaust gas flow to the LP turbine, i.e. in the turbine cooling air 21, preferably at the coldest location of this supply conduit 23.
In addition, it is possible to let the heat exchanger 20 mentioned act in a fuel flow 31 without difficulty--which is advantageous when a gaseous fuel is involved--instead of placing it in the air conduit 4. The heating of the fuel just mentioned then takes place at the same time.
In an additional variant which is not represented, it is also possible to place the heat exchanger 20 in a main flow or auxiliary flow of the steam cycle. The recooling of the exhaust gas flow in the supply conduit 23 can also be effected, as an alternative to or cumulative with the heat exchanger 20, by spraying in a certain quantity of water or steam 24, it then being possible without difficulty--to omit the heat exchanger 20 completely in certain cases. Due to the measure mentioned last, there is an increase in the cooling medium flow for the LP turbine 19 so that the extraction at the end of expansion 16 must, if need be, be throttled. It is preferable to keep the amount of water or steam 24 sprayed in small because, in addition to the loss of water, it also causes a reduction in the efficiency. On the other hand, it should be mentioned that the electrical power generated is increased by this measure.
Where steam 24 is sprayed in, a maximized, desired increase in pressure for the cooling gas distribution in the LP turbine 19 can be achieved with the aid of a jet apparatus or a mixing location 25. The steam 24 to be sprayed in can be of any given origin. It is advantageous to extract it from the exhaust heat boiler 29 or from the steam turbine 30 of the steam cycle 33, such a steam cycle being described, for example, in EP-B1-0 150 340.
The reduction in the temperature in the exhaust gas flow 17 to the level necessary for cooling the LP turbine 19 can also take place by an admixture of colder air, which can take place via the water or steam supply 24. In the through-connected gas turbine operation, this air is preferably extracted at an appropriate tapping location 28 in the compressor 1b. The extraction can also, of course, take place from the air conduit 4, the function of the jet apparatus 25 for increasing the pressure of the cooling air being then applied in this case also.
A cleaning unit 22 placed in the supply conduit 23 of the exhaust gas flow to the LP turbine 19 ensures that the turbine exhaust gases used for cooling can, depending on the fuel used, be cleaned.
Another favorable solution for the turbine and heat generator cooling, particularly in the case of combined installations, can take place by means of steam.
The fuel 31 necessary for feeding the heat generator 7 at the high-pressure end and the heat generator 18 at the low-pressure end is, in order to minimize energy losses, preheated as far as possible in counterflow to the combustion gases in the waste heat boiler 29 of the steam process 33 unless, as described above, it is used for recooling the turbine cooling air 21.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practised otherwise than as specifically described herein.
______________________________________Designation list______________________________________ 1a, 1b Compressors 2 Intercooler 3 Induced air 4 Air conduit from the compressor 5 Cavern 6 Air conduit from and to the cavern 7 Heat generator 8, 9, 10 Actuating elements10a, 10b Actuating elements11 Heat exchanger12 Conduit system in the cavern region13 Heat accumulator14 Electrical machine15 High-pressure turbine16 Cooling gas extraction location17 Cooling gas conduit18 Heat generator19 Low-pressure turbine20 Heat exchanger21 Cooled exhaust-gas flow22 Cleaning unit23 Cooling gas flow23a, 23b Cooling gas flows24 Water or steam conduit25 Jet apparatus or mixing location26 Booster fan27 Tapping conduit28 Tapping location29 Waste heat boiler30 Steam turbine31, 31a Fuel conduits32 Gas turbine group33 Steam cycle34 Air storage installation______________________________________ | In a method for operating a gas turbine group (32) having an integrated steam process (33) and having an air storage installation (34), a partial mass flow (17) is extracted from a high-pressure turbine (15) of the gas turbine group (32) and passed through a heat exchanger (20) for cooling one or a plurality of structures of the gas turbine group (32). This heat exchanger (20) is operated by a cooler medium (4, 6). The partial mass flow (17) cooled in this way is subsequently passed through the structures (18, 19) to be cooled of the gas turbine group (32). By this means, the cooling is achieved of, in particular, the structures installed downstream of the high-pressure turbine (15). The heat generator (18) connected downstream and the low-pressure turbine (19) can be connected in parallel or in series. It is therefore possible to achieve cooling of the loaded structures of the gas turbine group (32) without, in the process, affecting the working gas balance of the installation. | 5 |
TECHNICAL FIELD
[0001] This document generally describes friction and wear reduction techniques for equipment positionable in a wellbore, more particularly friction and wear reduction techniques using graphene as a lubricant.
BACKGROUND
[0002] In connection with the recovery of hydrocarbons from the earth, wellbores are generally drilled using a variety of different methods and equipment. According to one common method, a roller cone bit or fixed cutter bit is rotated against the subsurface formation to form the wellbore. The drill bit is rotated in the wellbore through the rotation of a drill string attached to the drill bit and/or by the rotary force imparted to the drill bit by a subsurface drilling motor powered by the flow of drilling fluid down the drill string and through downhole motor.
[0003] Frequently, as a well is being drilled, a string of coupled casing is run into the open-hole portion of the well bore and cemented in place by circulating cement slurry in the annulus between the exterior of the casing string and the wall of the wellbore. This is done by methods known in the art and for drilling purposes known in the art. Then the wellbore is drilled deeper. When drilling deeper, the rotating drill string is run through the interior of the casing string with the bit on the bottom of the drill string. The drill string comprises drill pipe joints joined together at tool joints (i.e. thread connections) and is rotated by the drilling rig at the surface. As the drill string is rotated the drill pipe, and more particularly the larger outside diameter portion of the tool joints may rub against the interior wall of the casing.
[0004] Rotating drill strings, like all moving mechanisms, exhibit friction that can result in mechanical wear of either or both the casing and the drill string. Friction and mechanical wear can cause drilling inefficiencies, due to increased power needed to overcome frictional resistance or due to maintenance or repair of assemblies due to wear.
DESCRIPTION OF DRAWINGS
[0005] FIG. 1 is a diagram of an example drilling rig for drilling a wellbore.
[0006] FIG. 2 is a flow diagram of an example process for a friction and wear reduction technique for downhole tools disposed in a wellbore.
[0007] FIG. 3 is a flow diagram of an example subsequent operation for friction and wear reduction techniques for downhole tools disposed in a wellbore.
[0008] FIG. 4 is a flow diagram of an example process for the application of lubricant for downhole tools.
DETAILED DESCRIPTION
[0009] FIG. 1 is a diagram of an example drilling rig 10 for drilling a wellbore 12 . The drilling rig 10 includes a drill string 14 supported by a derrick 16 positioned generally on an earth surface 18 . The wellbore 12 is at least partly lined by a casing 34 . The drill string 14 extends from the derrick 16 into the wellbore 12 through a bore in the casing 34 . The lower end portion of the drill string 14 includes at least one drill collar 20 , and in some implementations includes a subsurface drilling fluid-powered motor 22 , and a drill bit 24 . The drill bit 24 can be a fixed cutter bit, a roller cone bit, or any other type of bit suitable for drilling a wellbore. A drilling fluid supply system 26 circulates drilling fluid (often called “drilling mud”) down through a bore of the drill string 14 for discharge through or near the drill bit 24 to assist in the drilling operations. The drilling fluid then flows back toward the surface 18 through an annulus 28 formed between the wellbore 12 and the drill string 14 . The wellbore 12 can be drilled by rotating the drill string 14 , and therefore the drill bit 24 , using a rotary table or top drive, and/or by rotating the drill bit with rotary power supplied to the subsurface motor 22 by the circulating drilling fluid.
[0010] To reduce the amount of friction between the drill sting 14 and the casing 34 , a lubricant layer 60 is applied to the outer surface 19 of the drill string 14 , and a lubricant layer 62 is applied to an inner surface 21 of the bore of the casing 34 . In some embodiments, the lubricant layers 60 , 62 can be layers of graphene.
[0011] In some embodiments, graphene can be applied to the inner surface 21 of the casing 34 and the outer surface 19 of the drill string 14 to form the lubricant layers 60 , 62 . For example, graphene in a powdered form may be sprinkled, blasted, power coated, or otherwise applied to the casing 34 and the drill string 14 . In another example, the casing 34 and the drill string 14 may be contacted (e.g., rubbed) with solid graphite to leave behind graphene layer as the lubricant layers 60 , 62 . In some embodiments, graphene can be suspended in a liquid (e.g., ethanol) to form a graphene suspension, and the suspension can be sprayed onto the inner surface of the casing 34 and the outer surface 19 of the drill string 14 to form the lubricant layers 60 , 62 . For example, the graphene suspension may be sprayed using commercially available air-powered or airless sprayers.
[0012] In some implementations, commercially available solution processed graphene (SPG) containing graphene monolayer flakes dispersed in ethanol having a weight concentration of graphene as 1 mg/L can be used on the inner walls of the casing 34 , liners and risers, and/or on the outer surface 19 of the drill string 14 at the start of a drilling operation. SPG can be sprayed or sprinkled on the intended steel surfaces using any appropriate commercially available spraying or sprinkling systems.
[0013] In some implementations, graphene can provide improved tribological properties, and the application of graphene on contacting downhole surfaces can reduce friction and wear. In some implementations, the contact between the casing 34 and the drill string 14 downhole can wear out lubricant layers 60 , 62 , and replenishment of the lubricant coatings, e.g., graphene, may be provided. The lubricant layers 60 , 62 can be reapplied by sprinkling solution-processed graphene on drill pipes, drill collars, the bottom hole assembly, or other downhole tools when they are tripped out of the wellbore 12 so that a fresh coating can be established. In some implementations, solution processed graphene can be added on a continuous basis to the circulating drilling fluid to help replenish the worn out graphene coatings downhole.
[0014] In some implementations, the application of a protective graphene layer can reduce the coefficient of friction during rotary operations, as well as reduce the sliding friction during tripping or during sliding drilling. In some implementations, the application of protective graphene layers can also reduce the wear on the inner surface 21 of the casing 34 , wear on the drill string 14 , as well as the mechanical wear of bottom hole assembly tools during drilling operations. In some implementations, application of graphene can improve the wellbore integrity and the life of downhole tools/tubulars, e.g., measurement-while-drilling tools, logging while drilling tools, stabilizer blades, connection subs, bits, teeth, rotary steerable systems, drill pipes, heavy weight drill pipes, drill collars.
[0015] A monitor 70 measures an indicator of mechanical wear between the drill string 14 and the casing 34 . In some implementations, the monitor 70 can measure a concentration of one or more predetermined materials suspended in the drilling fluid and corresponding to at least one of the drill string 14 and the casing 34 . For example, the drill string 14 and the casing 34 may be constructed of known materials (e.g., steel, iron, aluminum, ceramic), and the monitor 70 may be configured to detect and measure amounts of the known materials worn off from the downhole components and suspended in drilling fluid that flows to the surface from downhole. The concentrations of such known materials may be measured over time to estimate an amount of wear that has occurred along the drill string 14 and the casing 34 .
[0016] In some implementations, the monitor 70 can measure an amount of torque developed between the drill string 14 and the casing 34 . For example, the amount of torque developed between the drill string 14 and the casing 34 may be used to estimate the amount of wear that has occurred along the drill string 14 and the casing 34 and/or estimate the downhole friction acting between them.
[0017] In some implementations, the monitor 70 can indicate one or more mechanical dimensions of the drill string 14 and/or the casing 34 . For example, the drill string 14 may start its service life with an initial outer diameter that gradually shrinks as friction and mechanical wear erode away the outer surfaces of the drill string 14 . In another example, the casing 34 may start its service life with an initial inner diameter that gradually grows as friction and mechanical wear erode away the inner surface of the casing 34 . The monitor 70 may be configured to measure these and/or other mechanical dimensions of the drill string 14 and/or the casing 34 to determine an amount of wear that has occurred along the drill string 14 and/or the casing 34 .
[0018] In some example drilling operations, the casing 34 , liners, or risers can run in the wellbore 12 according to a drilling program. The drill string 14 can be tripped in to the wellbore 12 to drill the well. The downhole wear in casings can be monitored by the monitor 70 by running in logs (e.g., ultrasonic imager log, caliper log) to measure the inside diameter of the casing 14 . Based on the log readings, percent of casing wear volume can be estimated using wear models. In some examples, if the percent of casing wear volume is more than a tolerance amount, e.g., 20%, then steps to mitigate this wear can be taken. Such steps may involve adding commercially available SPG to the circulating drilling fluid so that it can replenish the lubricating layers 60 , 62 . However, in examples in which the drilling program permits, the drill string 14 can be tripped out to reapply SPG on the outer surface 19 to further mitigate wear.
[0019] In some implementations, casing wear can be monitored or estimated by inspecting the drilling fluid for steel shavings, visually or using any other appropriate inspection technique. For example, collected steel shavings can be used to estimate the casing wear volume, and if beyond tolerance, then mitigation steps can be taken. In such examples, if the application of SPG does not show any improvement in downhole casing wear, then the concentration of graphene in the SPG solution can be increased.
[0020] FIG. 2 is a flow diagram of an example process 200 for a friction and wear reduction technique for downhole tools disposed in a wellbore, such as those discussed in the descriptions of FIG. 1 . Though depicted sequentially as a matter of convenience, at least some of the actions shown can be performed in a different order and/or performed in parallel. Additionally, some embodiments may perform only some of the actions shown. In some embodiments, the operations of FIG. 2 , as well as other operations described herein, can be implemented as instructions stored in a computer-readable storage medium and executed by a processor,
[0021] The process 200 starts by providing an outer tubular member having a bore with an inner surface (block 205 ). For example, the casing 34 of FIG. 1 has the inner surface 21 along the bore. A first lubricant layer is applied to at least a portion of the inner surface of the outer tubular member (block 210 ). For example, a layer of graphene can be applied (e.g., sprayed, sprinkled, rubbed) onto the inner surface 21 as the layer 62 . The outer tubular member is then positioned in at least a portion of the wellbore (block 215 ). For example, the casing 34 can be placed in the wellbore 12 .
[0022] The process 200 continues by providing a drilling assembly including an inner member having an outer surface, said inner member having a central longitudinal axis aligned with a central longitudinal axis of the outer member (block 220 ). For example, the drill string 14 may be provided, and the drill string 14 has the outer surface 19 . A second lubricant layer is applied to at least a portion of the outer surface of the inner member (block 225 ), and the inner member is inserted into the bore of the outer tubular member (block 230 ). For example, a layer of graphene can be applied (e.g., sprayed, sprinkled, rubbed) onto the outer surface 19 as the lubricant layer 60 , and then the drill string 19 can be inserted into the bore of the casing 34 .
[0023] A drilling fluid is provided through the bore of the drilling assembly (block 235 ). For example, drilling fluid can be circulated through the bore of the drill string and returned back to the surface through the annulus between the drill string and the casing in a conventional drilling operation in block 235 .
[0024] An indicator of at least one of mechanical wear and friction between the outer member and the inner member is measured (block 245 ). For example, the monitor 70 can be used to measure an indicator of mechanical wear between the drill string 14 and the casing 34 . If the measured indicator is determined (block 250 ) to have not exceeded a predetermined threshold level, then a subsequent action is not triggered in response to the determining (block 255 ). If the measured indicator is determined (block 250 ) to have exceeded the predetermined threshold level, then a subsequent operation is triggered in response to determining that the measured indicator exceeds the predetermined threshold level (block 260 ).
[0025] In some embodiments, the measured indicator can be a concentration of one or more predetermined materials suspended in the drilling fluid and corresponding to at least one of the outer member and the inner member. For example, as the drill string 14 and the casing 34 wear, some of the material used to construct the drill string 14 and the casing 34 may be worn off and enter the drilling fluid. In some examples, the worn material may be suspended in the drilling fluid. In some examples, the worn material may mix with the drilling fluid. In some examples, the worn material may interact chemically with one or more compounds or elements of the drilling fluid. As the drilling fluid recirculates back to the surface, the worn material or evidence of it is carried to the surface as well. In some embodiments, the monitor 70 can be configured to detect the worn material or evidence of it, for example, using a magnetometer, a spectrometer, reagent testing, or any other appropriate technique for detecting materials carried by the drilling fluid. In some implementations, when a predetermined amount of material is detected in the drilling fluid, a subsequent operation may be triggered. For example, graphene may be added to drilling fluid or graphene may be re-applied to the drill string 14 by tripping it out.
[0026] In some embodiments, the measured indicator can be a measured amount of torque developed between the inner member and the outer member. For example, the monitor 70 can measure the amount of torque that is developed between the drill string 14 and the casing 34 . The measured torque can be used to determine an amount of friction between the drill string 14 and the casing 34 and/or can be used as an indicator of the amount of wear for the drill string 14 and the casing 34 . In some implementations, when a predetermined amount of torque is measured, a subsequent operation may be triggered. For example, graphene may be added to drilling fluid or graphene may be re-applied to the drill string 14 by tripping it out.
[0027] In some embodiments, the measured indicator can be one or more mechanical dimensions of at least one of the outer member and the inner member. For example, the monitor 70 or a human operator can use a caliper, gauge, or other appropriate device to measure the physical dimensions of the inner surface 21 of the casing 34 and/or the outer surface 19 of the drill string 14 . In operation, as the drill string 14 and the casing 34 wear, the dimensions of the inner surface 21 may generally increase (e.g., the bore within the casing 34 may gradually get larger) and/or the dimensions of the outer surface 19 may decrease (e.g., the drill string 14 may erode). In some implementations, when a predetermined amount of wear is detected, a subsequent operation may be triggered. For example, graphene may be added to drilling fluid or graphene may be re-applied to the drill string 14 by tripping it out.
[0028] In some implementations, drilling parameters such as torque, hook load, and weight-on-bit can be monitored to estimate the downhole friction acting on the drill string. If, for example, the drill string experiences 20% higher torque than normal during the drilling activity, steps to mitigate the downhole friction should be taken. The steps to reduce friction, as described above, can include adding SPG to the circulating drilling fluid or if applicable in the drilling program, tripping out the drill string to reapply SPG on the outer surfaces. In another example, if the drilling rig is working near its rated torque capacity, then the drill string can be tripped out to reapply SPG on its outer walls.
[0029] Another example method to monitor downhole friction can include estimating the friction factor using appropriate models. For example, a friction factor of higher than 0.5 in the cased hole section may suggest that the drill string should be tripped out to reapply SPG. Even higher values of friction factors, e.g., 0.8 or 0.9, can be addressed by using relatively higher concentrations of graphene in the SPG solution. If selected concentrations of graphene used in SPG do not help mitigate downhole friction, the concentration of graphene in SPG can be further increased.
[0030] In various implementations, the wear on the drill string 14 , including the drill pipe body, tool joints and the any other component in the bottom hole assembly, can be monitored by inspecting visually, or by using any other appropriate inspection technique, to analyze the wear on the drill string 14 when it is tripped out during drilling operations. In some implementations, measuring the wall thickness of the drill pipe or any component in the bottom hole assembly can be one of the techniques used to determine the wear in the drill string 14 . For example, a 5% or greater reduction in wall thickness may indicate a need for reapplication of SPG on the outer surface 19 . Additionally, areas on the drill string that display shine and wear due to downhole friction may be selected for reapplication of SPG solution to replenish the worn away layers of graphene to mitigate friction.
[0031] FIG. 3 is a flow diagram of an example subsequent operation 300 for friction and wear reduction techniques for downhole tools disposed in a wellbore. In some implementations, the subsequent operation 300 may be the subsequent operation triggered in block 260 of FIG. 2 .
[0032] The operation 300 starts by extracting the inner member from the bore (block 305 ). For example, the drill string 14 of FIG. 1 can be extracted from the casing 34 . A lubricant layer is then applied to the outer surface (block 310 ) and the inner member is re-inserted into the bore. For example a layer of graphene can be re-applied (e.g., sprayed, sprinkled, rubbed) onto the outer surface 19 , and then the drill string 14 can be re-inserted into the casing 34 .
[0033] In another implementation, the subsequent operation triggered in block 360 of FIG. 2 can include increasing a concentration of graphene suspended in the drilling fluid. For example, when the monitor 70 determines that indications of friction or wear have exceeded a predetermined threshold, the monitor 70 can transmit a signal as an indicator to additional equipment or human operators that one or more lubricants, such as graphene, should be added to the drilling fluid being pumped downhole to carry the lubricant to the inner surface 21 and/or the outer surfaces 19 .
[0034] FIG. 4 is a flow diagram of an example process 400 for the application of lubricant for downhole tools, such as those described in FIG. 1 . Graphene monolayer flakes dispersed in ethanol can be applied on steel surfaces by spraying or sprinkling SPG on the intended steel surfaces using any appropriate commercially available spraying or sprinkling systems. Application of this graphene-containing ethanol solution on the steel surfaces, and further evaporation of the liquid ethanol part, leaves behind few layers of graphene on the steel surfaces. In some implementations, reapplication of spraying SPG can be done based on field measurements and/or estimation of downhole friction and wear parameters as explained in the description of the process 400 below.
[0035] The process 400 starts in block 401 during the drilling of any appropriate oil or gas well at a well site. Lubricant layers of graphene can be applied to the tubulars used during the drilling operation, e.g., casings, liners, risers and the drill string including the bottom hole apparatus (BHA). At block 402 , casings, liners, and risers are used in any appropriate drilling operation and can experience contact with the drill string on their inner walls. At block 404 , SPG is sprayed on the inner as well as outer walls of the casings, liners and risers that are run in for drilling the well. Inner walls may have contact with the outer body of the drill string during the drilling operation, and as such graphene may be used to reduce wear and friction. Outer walls may have contact with the inner walls of the previously run in casings, liners, and risers in the well when a new set is being run in to be installed. In such example situations, graphene can help reduce friction and wear between the outer body of the casing run in and the inner body of the previously installed casing.
[0036] The casings, liners, and risers are run into the hole after application of SPG solution on the inner and outer was at block 405 . At block 408 , the downhole casing, liner, and riser wear are measured or estimated using calipers or other techniques as practiced in the industry.
[0037] At block 411 the measured and estimated values of downhole friction and wear are compared with predetermined tolerance limits set for the operation. If the predetermined tolerance limits have not been exceeded, then the drilling operation continues at block 414 , e.g., until the target depth is reached. If the predetermined tolerance limits have been reached at block 411 , then SPG can be added to the circulating drilling fluid to replenish the graphene layers that have worn out due to downhole contact. After addition of the SPG, drilling can continue at block 414 until the target depth. Further monitoring of friction and wear can be done to determine the effectiveness of adding SPG. In some implementations, if the predetermined tolerance limits have been reached at block 411 , then the drill string can be tripped out at block 413 in order to replenish the graphene layers that have been worn out due to downhole contact. After tripping out, SPG can be sprayed again on the outer walls of the drill string to replenish the graphene layers in block 406 . The drill string can be subsequently tripped in to continue with the drilling operation in block 407 . In some implementations, the operations of blocks 412 and 413 can be followed separately or together to reduce the downhole friction and wear.
[0038] If tripping out is required as a part of the drilling operation at block 415 , for example to change the bit or BHA or due to any other operational reason, the wear on the drill string is measured or estimated at block 416 . If tripping out of the drill string is not required at block 415 , then additional monitoring of the drilling parameters and wear is done while continuing to drill ahead to the target depth.
[0039] Referring now to block 403 , the drill string including the BHA is used in any appropriate drilling operation to reach the target depth. The outer wall of the drill string can experience contact with the inner wall of the casings, liners, and risers during the drilling operation. To reduce friction and wear due to such contact, at block 406 SPG is sprayed on the outer wall of the drill string including the BHA before tripping it in the wellbore at block 407 .
[0040] As drilling operations progress toward the target depth, the drilling parameters are monitored at block 409 to determine if the efficiency of the drilling operation may be improved and/or downhole friction and wear may be reduced, by taking further steps to lubricate surfaces of the drill string. At block 410 , the downhole friction experienced in the riser and the cased hole section (e.g., due to contact with the outer wall of the drill string) is estimated using techniques known in the industry.
[0041] At block 411 the measured and estimated values of downhole friction and wear are compared with predetermined tolerance limits set for the operation. If the predetermined tolerance limits have not been exceeded, then the drilling operation continues at block 414 . If the predetermined tolerance limits have been reached at block 411 , then the drill string is tripped out at block 413 in order to replenish the graphene layers that have been worn out due to downhole contact. After tripping out, SPG is sprayed again on the outer walls of the drill string to replenish the graphene layers in block 406 . The drill string is subsequently tripped in to continue with the drilling operation in block 407 . In some implementations, if the predetermined tolerance limits have been reached at block 411 , then SPG can be added to the circulating drilling fluid to replenish the graphene layers that have worn out due to downhole contact. After addition of the SPG, drilling can continue at block 414 until the target depth. In some implementations, the operations of blocks 412 and 413 can be followed separately or together to reduce the downhole friction and wear.
[0042] If at block 415 , it is determined that the drill string does not need to be tripped out, then the drilling parameters are monitored again at block 409 . If at block 415 , it is determined that the drill string does need to be tripped out, then the wear on the drill string is measured or estimated at block 416 . If at block 417 the measured wear on the drill string is determined to be higher than predetermined tolerance limits, then SPG is sprayed on the outer walls of the drill string at block 406 to replenish the worn out graphene layers. If the measured wear is within the predetermined tolerance limits, then the drill string is tripped back in at block 407 to continue the drill operation, e.g., to reach the target depth.
[0043] Although a few implementations have been described in detail above, other modifications are possible. For example, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Accordingly, other implementations are within the scope of the following claims. | The subject matter of this specification can be embodied in, among other things, a method that includes providing an outer tubular member having a bore with an inner surface, applying a lubricant layer to at least a portion of the inner surface of the outer tubular member, positioning the outer tubular member in at least a portion of the wellbore, providing a drilling assembly including an inner member having an outer surface, applying a lubricant layer to at least a portion of the outer surface of the inner member, inserting the inner member into the bore of the outer tubular member, providing a drilling fluid through the bore of the drilling assembly, rotating the inner member relative to the outer member, measuring an indicator of mechanical wear between the outer member and the inner member, determining that the measured indicator exceeds a predetermined threshold level, and triggering a subsequent operation. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to wheeled vehicles and in particular to trailered vehicles and the inclusion of means therewith for externally greasing the inner and outer wheel bearings of each wheel without removing the bearings.
One problem faced by the trailer owner is that of failed wheel bearings and axles and which arise from insufficient lubrication. This problem is of particular concern to the fisherman, in that with the insertion and removal of the trailer from the water, especially when the wheel bearings and grease are hot, the wheel grease tends to wash from the wheel hub and/or water is trapped in the hub with resulting rusting and accelerated wear. The rental trailer industry also shares in this problem, but there it is a consequence of protracted maintenance cycles. The resulting shortage of lubricant causing higher operating temperatures and resultant bearing failure. Some of the results in either case being worn bearings, pitted bearing races and/or possibly damaged wheel hubs, requiring the replacement thereof and/or oftentimes the replacement of the wheel's entire backing plate.
In order to alleviate the foregoing problems, a number of devices have been developed and which are disclosed in a number of U.S. Patents, for example, U.S. Pat. Nos. 3,077,948; 3,395,015; 3,649,080; 3,395,950; 3,955,852; 4,106,816; and 4,190,133. A feature common to each of the foregoing devices is that of including a zerk fitting in a special dust cap that mounts over the wheel hub and axle end. Grease injected into the grease fitting then permeates through the entire hub to grease the inner and outer bearings. In practice, however, with the buildup of old grease, this oftentimes does not occur and instead the new grease tends to build up in the region of the outer bearing, with no grease permeating to the inner bearing. Also and where water has leaked into the hub, as the old grease and water is forced out of the hub with the addition of new grease, it tends to ruin the inner grease seal. Thus, wheel failure tends to occur at the inner bearing and race.
Two attempts to overcome this problem can be seen in U.S. Pat. Nos. 3,460,874 and 3,642,237 and wherein zerk fittings have been mounted in the projecting external portion of the wheel hub itself and which ostensively permits the introduction of grease in between the bearings. Again, however, as the grease ages, one is not always certain that the newly injected grease will migrate to each of the wheel bearings, but may rather only collect in the middle region opposite the internal sides of the two bearings.
It is for the foregoing reasons that the present invention contemplates a modification of a conventional wheel hub and backing plate to permit the application of grease directly at each of the inner and outer bearings and thereby ensure proper bearing lubrication and the prolongation of the wheel's life. It achieves this end by providing grease ports that are accessible from the front of the wheel, but which channel the grease to the inner and outer bearings.
The above objects, advantages and distinctions, as well as the construction of the present invention, will however be described in greater detail hereinafter with respect to the appended drawings. Before referring thereto, it is to be recognized though that the following description is made with respect to the presently preferred embodiment only and is not intended to in any way be self-limiting.
SUMMARY OF THE INVENTION
Apparatus for lubricating the bearings of a wheeled vehicle directly at the front and rear bearings without removing the bearings from the wheel. In one embodiment, the apparatus includes a zerk fitting mounted along the elongated outer wall of the wheel hub adjacent the front or outer bearing. In diametrically opposed relation thereto, a pressure relief valve is mounted and which completes the flow path and assures unimpeded flow of lubricant to the outer bearing. A second zerk fitting extends through the wheel rim and backing plate to a grease channel containing weldment mounted to the backing plate, and wherein the grease channel opens to the rear or inner bearing. An appurtenant pressure relief valve containing weldment mounted in diametrically opposed relation to the second inlet fitting assures grease flow to and about the inner bearing. The invention is thus mountable to any wheeled vehicle, either as manufactured or in a retrofit fashion.
In another embodiment, and in lieu of a stamped steel hub, a cast metal hub includes a hollow chamber in flow communication with a zerk fitting containing a bored lug bolt. Grease may thereby be directed through the lug bolt and chamber to an inlet port adjacent the inner bearing. A pressure relief channel opposite the inlet port and passing through a second hollow chamber and lug bolt, complete the flow path.
In yet another embodiment, a brake drum assembly contains a pair of press fit studs and wherein each stud has a zerk fittng mounted in a longitudinal bore therethrough. A hollow tube connected to the other end of one of the studs couples admitted grease to an inlet port through the hub adjacent the inner wheel bearing. An opposed outlet port coupled to a second tube and the other stud provide a pressure relief path.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of the invention in partial cutaway in a typical wheel hub and backing plate relative to a wheel and tire.
FIG. 2 shows a partial cross-section view of the wheel hub of FIG. 1.
FIG. 3 shows a cross-section view of a cast backing plate and hub having molded grease conveying cavities and ported lug bolts opening thereto.
FIG. 4 shows a cross-section view of a brake drum and hub assembly including ported, press fit studs with tubular grease channels.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a partially sectioned perspective view is shown of a typical trailer wheel 2 and mating wheel hub 4 that has been modified to include the present invention. Before addressing the details thereof, however, it is to be recognized that the present invention would typically be included with each wheel hub 4 of a vehicle. Consequently and since the construction would be similar for each other wheel, the following description will be directed to a single hub only.
Accordingly, FIG. 1 depicts a conventional wheel rim 5 and to which is mounted a tire 6 of an appropriate size. The wheel rim 5 is mounted to the wheel hub 4 and its associated backing plate 8 via a plurality of lug nuts 10 that are threadably secured to a number of press fit studs 12 which project from the backing plate 8. Alternatively, it is to be recognized that a number of lug bolts that mate with a number of threaded holes in the backing plate 8 might be used to secure the wheel 5 to the backing plate 8. A dust cover (not shown) mounted to the end of the wheel hub 4 protects the interior of the hub 4 from dirt and other debris that might otherwise accumulate and/or find its way into the hub 4 with deleterious effects to the bearing and/or axle 25 contained therein. As mentioned and for a boat trailer, a particular concern is that after towing the boat to a launching site and upon backing the trailer into the water and launching the boat, the lubricant can wash away and/or water can become trapped in the hub.
In order to overcome this problem and ensure that sufficient lubricant is maintained in the cavity of the wheel hub 4, a pair of inlet zerk fittings 16 and 18 are mounted to the wheel hub 4 and backing plate. Specifically, a first inlet zerk fitting 16 is mounted to the exposed outer portion of the hub 4 adjacent the front or outer bearing (not shown). In diametrically opposed relation thereto, a zerk-type pressure relief valve 20 is also mounted to the hub 4. Thus, upon injecting grease into the zerk fitting 16, the grease collects inside the hub 4 around the outer bearing and upon filling the space, the old grease is pushed through the pressure relief valve 20. This condition indicating that sufficient lubricant has been injected. Alternatively, grease may ooze from around the outer washer 19 and castellated nut 21, that hold the front bearing in place relative to the axle 25, and which condition also demonstrates proper lubrication.
The second inlet zerk fitting 18 is mounted through a hole 19 in the wheel rim 2 and is threadably coupled to the backing plate 8 and a standoff or weldment 22 that is secured thereto. This fitting permits the further lubrication of the rear or inner wheel bearing. Specifically, the weldment 22 includes an internal grease conveying channel (not shown) that terminates at a port adjacent the inner bearing. A further ported channel in a second diametrically opposed weldment 23 opens from the wheel hub 4 and terminates in a pressure relief valve 24. Thus, upon injecting grease through the zerk fitting 18, it fills the interior of hub 4 and the space around the inner wheel bearing. At the same time the old grease is pushed through the pressure relief fitting 24. Consequently, the present invention not only permits the greasing of each wheel's outer wheel bearing, but also the inner wheel bearing, without removing the bearings from the wheel.
As previously mentioned, the prior art principally provides for a modified dust cover, including a zerk fitting and pressure relief valve. In theory, an operator is supposed to be able to inject grease at the zerk fitting and be assured that due to the pressure of the grease gun, the grease will flow through the front bearing to completely fill the wheel hub and thereby also lubricate the rear bearing. Concurrently, old grease will ooze from a relief valve in the dust cover. While this may occur with the first greasing of the wheel hub 4, as the wheel grease ages and hardens, more often than not, it has been found that the fresh grease will not penetrate the front bearing to replenish the grease in the wheel hub. Rather, the grease only collects within the dust cover, adjacent the outer bearing, without lubricating the inner bearing.
Turning attention next to FIG. 2, a partial crosssection view is shown through the wheel 5 and hub 4 of FIG. 1. For purposes of clarity, however, the wheel studs 12, nuts 10, axle 25 and various other details have not been shown. From FIG. 2, it is to be noted that the zerk fitting 16 for the outer bearing 30 is mounted to the wheel hub 4 just back of the outer bearing 30. Similarly, the outer pressure relief valve 20, which comprises a zerk fitting with its innards removed, is mounted in opposed relation to the zerk fitting 16. The fittings 16 and 20 are in turn mounted to the hub 4 by boring and tapping appropriately sized holes through the wheel hub 4, before threadably securing each thereto. Upon injecting grease through the inlet zerk fitting 16, it collects inside the wheel hub 4 in surrounding relation to the axle 25 and outer wheel bearing 30. Once enough grease has collected to cause the interior pressure to rise, the residue begins to ooze from the relief valve 20.
The rear bearing 34, in turn, is greased via the channel containing weldments 22 and 23 secured to the backing plate 8 and the hub 4. The channel 36 in the upper weldment 22 is aligned with a hole bored and tapped through the backing plate 8 and the zerk fitting 18 is mounted thereto. The other end of the channel 36 is aligned with a hole 37 bored through the hub 4 adjacent the inner wheel bearing 34. The grease channel 40 of the opposed weldment 23 is similarly aligned at one end with a hole 39 bored through the bottom of the hub 4 and at the other end with a hole bored and tapped through the backing plate 8 and wherein a second pressure relief zerk-type valve 24 is mounted. Thus, upon injecting grease at the zerk fitting 18, it passes through the grease channel 36 and collects in the region adjacent the inner wheel bearing 34. An inner grease seal 44, surrounded by a press fit metal retainer 45 and mounting against the rear bearing 34 and about the axle 25, prevents the grease from being ejected therefrom. Instead, and once the interior of the hub 4 is filled, the grease is forced out through the channel 40, until it appears at the pressure relief valve 24.
While over time the grease may still harden and/or run from the wheel hub 4, now at least the operator has a readily available mechanism for ensuring proper lubrication to the outer and inner bearings 30 and 34, without having to remove the wheel 2 and individually repack the bearings of each wheel. Because of the time involved in the latter operation, the present invention finds particular savings to the rental trailer industry as well as to the fisherman. Now too the wheel bearings can be lubricated with relative ease and with the assurance of fewer costly breakdowns.
Turning attention next to FIG. 3, an alternative embodiment of the invention is shown in cross-section relative to a commercially available cast wheel hub/backing plate assembly 50 that includes a hub portion 54 and a backing plate portion 56. Extending rearwardly from the assembly 50 are a number of cast strengthening ribs 52 that extend between the backing plate portion 56 and the hub portion 54. These strengthening ribs 52 are typically radially disposed about the inner surface of the backing plate portion 56 and serve to support the backing plate portion 56 against encountered road stresses. As typically constructed, each rib 52 also includes a hollow interior cavity 57 that is unconnected to any other portion of the assembly 50.
For purposes of the present invention, the assembly 50 has been modified by re-positioning the threaded lug bolts 58 let through the backing plate portion 56 so that at least two of the holes 58 open up into the hollow cavities 57 of two of the strengthening ribs 52. Ports 60 and 62, in turn, are let through the hub portion 54 to the cavities 57 adjacent the space in the hub portion 54 whereat the inner bearing is positioned. Upon thus injecting grease into the upper hollow cavity 57, it is directed through the port 60 adjacent the inner bearing. Upon filling this space, the old grease is forced out through port 62 and the lower cavity 57.
In this latter regard, FIG. 3 also discloses the modification of two of the typical lug bolts used therewith. Specifically, the upper and lower lug bolts 64 and 66 have been modified to include longitudinal grease conveying bores 68 and 70. An inlet zerk fitting 66 mounted to the outer end of the upper bore 68 directs grease flow through the bore 68 and thence via the hollow chamber 57 and port 60 to the inner bearing.
A diametrically opposed pressure relief path is also provided. Specifically, the lower relief port 62 extends from the interior of the hub portion 54 to the lower hollow cavity 57 and thence to the second lug bolt 66 and via its grease conveying bore 70 to a zerk-type pressure relief fitting 72. Thus, lubricant is again directed to the region adjacent the inner bearing. While not shown, it is also to be appreciated that the assembly of FIG. 3 would typically include a pair of zerk fittings in the outer surface of the hub portion 54 in the fashion of FIG. 1. These fittings, as before, permitting the lubrication of the outer bearings.
Turning attention next to FIG. 4, a cross-section view is shown through yet another embodiment of the invention. In this embodiment, the invention is combined with a typical knock-out type hub 80 and brake drum 82 that migt be encountered with trailers having electric brakes. For this embodiment, a pair of threaded studs 84 and 86 are press fit into the outer annular portion 87 of the hub 80 and mount through mating holes 88 provided in the surface of the brake drum 82. As in FIG. 1, lug nuts 10 mount to the studs 84 and 86 and secure the wheel 5 and tire thereto. In passing, it is also to be noted that the studs 84 and 86 could be threadably secured to the backing plate portion 87, if they were of that type.
As should be apparent from FIG. 4, the studs 84 and 86 have also been modified in a fashion similar to that of the lug bolts 64 and 66 of FIG. 3 so as to provide longitudinal grease channels 90 and 92 therethrough. Mounted now however to the rear of the studs 84 and 86 are short holow tubes 94 and 96 and which are in flow communication with the bores 92 and 94 of the respective studs 84 and 86. The opposite ends of the tubes 88 and 90, in turn, mount through ports 98 and 100 let into the hub portion 80 adjacent the space occupied by the inner bearing and, as before, ensure that grease is provided thereto. Thus, new grease is admitted via the upper zerk fitting 96 and is conveyed via the tube 94 to the rear bearing while old grease is caused to flow out through tube 96 and pressure relief valve 98.
From the foregoing embodiments of FIGS. 1 to 4, it should be apparent that the invention is adaptable to a variety of available wheel assemblies. Even though too the invention has been described with respect to various presently preferred embodiments, it is to be appreciated that still other modifications may be made thereto without departing from the spirit and scope of the invention and whereby a wheel's inner and outer bearings may be lubricated without removing the bearings form the hub. Accordingly, the following claims should be interpretted so as to include all those equivalent embodiments within the spirit and scope thereof. | Apparatus mounting to the bearing containing hub of a wheeled vehicle and accessible from the front of each wheel for lubricating the inner and outer wheel bearings. A first zerk fitting and pressure relief valve coupled to the outside of the hub assure the lubrication of the outer bearing. A second zerk fitting mounting through the wheel rim and backing plate and opening to a grease conveying channel at the interior or the hub adjacent the inner bearing assure the lubrication thereof. In various alternative embodiments, the grease conveying channel is incorporated into appurtenant lug bolts, threaded studs, hollow wheel cavities and tubular extensions. | 1 |
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