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CROSS-REFERENCES
The present application is related to copending application Ser. No. 07/967,419 filed Oct. 28, 1992, U.S. Pat. No. 5,251,557, entitled "Sewing Machine With an Edge Guiding Device to Guide One or More Plies of Material" by inventor Gunter Rohr. U.S. Pat. No. 5,251,557 claims priority under the German application P 42 26 161.9 filed on Aug. 7, 1992. U.S. Pat. No. 5,251,557 is hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates to a method and device for automatically aligning a work piece and positioning the aligned work piece at the stitch forming location of a sewing machine.
Prior art reference U.S. Pat. No. 4,467,734, discloses an edge guide and material advancing device for seaming a tubular work piece and forming a fold at its edge. The tubular work piece is manually located on the sewing machine work surface, such that it is in the proper location to commence the sewing operation. After positioning the work piece, but before commencing the sewing cycle, a work positioning device is activated which moves a portion of the material and creates a surplus of material near the work piece edge. The work piece edge is not moved from its original location. This surplus of material acts as a material buffer or storage zone which facilitates the aligning of the work piece edge by making possible a shifting of the work piece edge without having to shift the entire work piece in a direction transverse to the sewing direction. In accordance with the invention of this prior art patent the plies of material to be stitched are properly aligned and manually located at the stitch forming location by the sewing machine operator. Thus this prior art reference does not eliminate the tedious and time consuming task that is eliminated by the subject invention.
When seaming two plies of cloth together, a sewing machine operator manually aligns the leading and margin edges of the plies of cloth, in the relative positions that they are to have when stitched together, and then locates the aligned plies under the presser foot of the sewing machine. This is a very tedious and time consuming portion of a sewing operation and the operator must be highly skilled to perform this operation efficiently and properly.
For the foregoing reasons, there is a need for a device and method that will automatically align both the leading and the margin edges of the work piece and then position the work piece in the correct relationship at the stitch forming location prior to commencement of the sewing operation.
SUMMARY OF THE INVENTION
The present invention is directed to an apparatus and method that satisfies this need. The method of the present invention includes the step of placing a ply of material to be sewed under an edge guiding device where it is detected by a first sensor. The first sensor activates gripper wheels that cause the first ply of material to move in the direction normal to the direction of feed and cause the margin edge of the ply of material to move toward a second sensor. When the margin edge of the ply of material is sensed by the second sensor the gripper wheels are stopped. Ply feeding wheels are then actuated that function to feed the ply of material toward the stitch forming location. The leading edge of the ply is sensed when it arrives at a third sensing device that is located a known distance from the stitch forming location. The ply feeding wheels continue to feed the ply past the third sensing device toward the stitch forming location for a predetermined distance. When multiple plies of material are to be stitched together these steps are then repeated or performed simultaneously for the second and subsequent plies of material that are to be stitched together. When all plies of material are properly aligned and located at the stitch forming location the presser foot is lowered and the sewing operation commences. An advantage of this method is that a tedious and time consuming element of the sewing operation is accomplished automatically and quickly. This not only makes the sewing operation less tedious for the operator but permits less skilled operators to perform the sewing operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a sewing machine that has the automatic ply aligning and positioning mechanism of this invention mounted thereon.
FIG. 2 is a front view of an edge guiding device of the type used in the automatic ply aligning and positioning mechanism of this invention.
FIG. 3 is a cross section view of the edge guiding device seen in FIG. 2.
FIG. 4 is an end view of the feeding and gripper wheel head of the edge guiding device seen in FIG. 2.
FIG. 5 is a top view of the work surface area of the sewing machine seen in FIG. 1.
FIG. 6 is a diagrammatic end view illustration of the material loading and stitch forming areas of the sewing machine seen in FIG. 1.
FIG. 7 is a block diagram of the control system for the automatic ply aligning and positioning mechanism.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
There is shown in FIG. 1 a front view of a sewing machine 100 having a sewing head 102 and a base 104. The sewing machine 100 has an upper edge guiding device 106 and a lower edge guiding device 108 mounted thereon. The sensors and retractable plates, which are unique to this invention, are not visible in this view. The subject invention can be used with an over edge sewing machine or any other type sewing machine.
An isolated view of upper edge guiding device 106 is shown in FIG. 2. The upper 106 and lower 108 edge guiding devices are structurally identical and thus only the upper will be discussed in detail. It should be noted that the edge guiding devices are disclosed in the above identified copending U.S. Pat. No. 5,251,557, and reference may be had to that U.S. Patent for a more complete disclosure of the structural components of these devices. It should also be noted that in U.S. Pat. No. 5,251,557 the edge guiding devices are elevated out of contact with the work piece and not actuated until the sewing operation commences and then function to maintain the margin edge of the material in proper alignment and feed the material along the line of feed at the proper rate. In the subject application the edge guiding devices perform the function of aligning the plies of material and then locating the aligned plies under the stitch forming mechanism. In accordance with this invention when the sewing process begins the edge guiding devices perform the same function as disclosed in the above referenced Application. The edge guiding device 106 has a first stepper motor 110 for driving the feeding wheel 13 that functions to advance the ply of material in the material feed direction and a second stepper motor 112 for driving the gripper wheels 4 that function to move the ply of material normal to the material feed direction. The stepper motors 110 and 112, which are conventional and not a part of this invention, can be controlled to rotate a specific number of rotations or fraction of a rotation. Thus, depending upon the diameter of the drive element and the drive ratios, a ply of material can be advanced a specific distance upon transmitting an actuation instruction to the stepper motor to run a specific number of steps.
The entire device 106 is supported at one end on a horizontal pivot shaft 114. The other end, which is the material engaging head of the device, rests on the main ply separator plate 1. The material engaging head can be lifted off the main ply separator plate 1 by pivoting the entire device about horizontal pivot shaft 114. The upper edge guiding device 106 can rely upon gravity or can include a mechanical device, such as a spring or an air cylinder, to assist in forcing the material engaging head into contact with the main ply separator plate 1. The lower edge guiding device 108 must include a mechanical device, such as a spring or air cylinder, to bias its material engaging head into contact with the main ply separator plate 1.
FIG. 3 is a cross section view of the upper edge guiding device 106 seen in FIG. 2. A housing 118 has the first stepper motor 110 mounted to its outer surface. First stepper motor 110 has an output shaft 116 with a pinion 117 secured thereto. A hollow shaft 119 is mounted for rotation by bearings 120 in the housing 118 and has a pinion 122 secured thereto. Pinion 122 is mechanically connected by way of a toothed belt 124 to pinion 117. Rotary drive is transmitted from stepper motor 110 through toothed belt 124 to the hollow shaft 119. A feeding wheel 13 is fixed to the free end of hollow shaft 119 and thus rotates therewith. The feeding wheel 13 has a plurality of openings 130 formed therein in which gripper wheels 4 are mounted for rotation on shafts 132. The peripheral edges of gripper wheels 4 are in driving engagement with worm gear 128 and are caused to rotate thereby. Worm gear 128 is secured to the free end of shaft 126 that is mounted for rotation within the hollow shaft 119.
The housing 118 is secured to one end of second stepper motor 112 by bolts 134. The other end of second stepper motor 112 is pivotally mounted to the base 104 of the sewing machine 100 about a pivot shaft 114. The output shaft 138 of second stepper motor 112 is secured to shaft 126 by a coupler 140. The feeding wheel 13 of upper edge guiding device 106 can be lifted off main ply separator plate 1 by pivoting the edge guiding device 106 upwardly about shaft 114.
FIG. 4 which is an end view of the feeding wheel 13 includes a ply of material designated 142 between the peripheral edge of feeding wheel 13 and a reaction plate 143. Reaction plate 143 has a cylindrical shaped concave surface 144 that cooperates with the peripheral edges of gripper wheels 4 to grip the material 142 so as to feed it in the precise amount intended. As a result of the concave shape of surface 144 a plurality of gripper wheels 4 can be in engagement with the material 142 at the same time which enhance the control and precision of this feed.
The sensors used in the device of this invention are of the retroreflector type in which emitted rays are reflected back to the sensor. The emitted rays are directed at a highly reflective surface, or a surface to which reflective tape has been applied. When the ply of material moves into the area where the rays are directed there is a change in the rays that are reflected back to the sensor. This change is detected by the sensor and the change is transmitted to the control system.
Diffuse type sensors could also be used. Diffuse type sensors recognize characteristics of a particular type of surface that they are intended to sense and do not require the presence of a highly reflective surface.
An example of the invention, in which a first top ply of material and a second bottom ply of material are to be stitched together, will be discussed with referring to FIGS. 5 and 6. This example can be applied to a sewing operation in which a single ply of material is being stitched or an operation in which more than two plies of material are being stitched together.
FIG. 5 is a top view of the sewing machine taken along a plane above the pressor foot 164. In this view only the upper edge guiding device 106 is visible. The top feeding wheel 13 with several top gripper wheels 4 are seen, at the free end of hollow shaft 119. The upper edge guiding device 106 overlies the main ply separator plate 1. The feeding wheel 13 is resting on surface 144 of the reaction plate 143. A top ply present sensor or first sensor 5 overlies the main ply separator plate 1. The first ply of material is placed on main ply separator plate 1 and moved to the right until it is under the upper feeding wheel 13. Depending upon the thickness of the ply of material, it may be necessary to raise the feeding wheel 13 by pivoting the upper edge guiding device 106 about its pivot 114. In so placing the first ply of material it passed under the first sensor 5 which recognized that a ply of material is now present and caused the top gripper wheels 4 to be actuated. Top gripper wheels 4 are actuated to rotate in the direction to move the material to the right, as seen in FIG. 5.
The term "margin edge" when used in this patent means the edge of the material that extends along the direction of material feed. The term "leading edge" when used in this patent means the leading edge of the material, that is in most instances, normal to the direction of material feed.
As the gripper wheels 4 move the top ply of material to the right the margin edge of the material approaches the top sensor or second sensor 10. When the second sensor 10 recognizes the margin edge of the top ply of material it causes the drive to the top gripper wheels 4 to be stopped. Thus the movement of the material in the direction lateral to the feed direction stops when the margin edge of the material is located below second sensor 10. Although the movement of the material to the right has been stopped, the top gripper wheels 4 remain under the control of second sensor 10. If the material were to move back to the left, sensor 10 would detect this and cause gripper wheels 4 to move the ply of material to the right until it is returned to its desired location.
When the margin edge of an individual ply of material is recognized by its sensor then the drive to its feeding wheel is actuated. In the example being discussed the drives to upper feeding wheel 13 and bottom feeding wheel 14 are actuated independently to move the materials toward the pressor foot 164 or stitch forming area. During the movement of the material toward the pressor foot 164 movement of the margin edge of the material drifts to the right or left will be detected by sensor 10 and corrected by gripper wheels 4.
A top ply plate 8 includes an edge 150 that overlies the top surface of main ply separator plate 1. As can be best seen in FIG. 6 top ply plate 8 has a slight downward inclination such that it directs the first ply of material toward the surface of the throat plate 160. A retractable sensor plate 7 is immediately below the top ply plate 8. Retractable sensor plate 7 extends horizontally at a level above the throat plate 160 and feed dogs 162. The top ply plate 8 and the retractable sensor plate 7 converge toward the stitch forming area such that the top ply of material is guided below the raised pressor foot 164 and over the leading edges of the feed dogs 162. Between the upper edge guiding device 106 and the stitch forming area is a third upper sensor 11. As the upper feeding wheel 13 is moving the first ply of material and the lower feeding wheel 14 is moving the second ply of material toward the stitch forming area the leading edges of the first and second plies of material are approaching upper third sensor 11 and lower sixth sensor 12. Provided the third 11 and sixth 12 sensors are directed at points at which the first and second plies of material are under the pressor foot 164, the feeding wheels 13 and 14 can be stopped at the point where the leading edge of the material plies is recognized.
However, the stitch forming area in some sewing machines is very congested and it is difficult to locate the third 11 and sixth 12 sensors close to the stitch forming area. In such situations the third 11 and sixth 12 sensors are located such that they recognize the leading edges of the material plies before they reach the stitch forming area. In this situation the following procedure is followed. When the sensors 11 and 12 recognize the leading edges of the first and second plies of material respectively they will cause the upper and lower feeding wheels 13 and 14 to continue to rotate a predetermined number of degrees which will move the material that they are causing to move a predetermined distance. This predetermined distance is such that the leading edges of the first and second plies of material will be located under the raised pressor foot 164 just short of the center line of the needle 170. This predetermined distance is represented as Y in FIG. 5.
Although, in this discussion the first or top ply of material was placed on the main ply separator plate first and then the second or bottom ply of material, this order could be reversed or both could be done simultaneously. It is important to note that each ply of material is aligned and located in the stitch forming area independently of the other plies.
A second or bottom ply of material 242 is placed against the underside of the main ply separator plate 1 moving it to the right such that it passes between the bottom feeder wheel 14 and the undersurface of main ply separator plate 1. It should be noted that the lower edge gripper device 108 is forced upwardly about its pivot axis such that bottom gripper wheels 2 are biased into engagement with surface 244 of reaction plate 243. Reaction plate 243 is secured to the undersurface of main ply separator plate 1. A bottom ply sensor or fourth sensor 3, as seen in FIG. 6, recognizes the presence of the second or bottom ply of material 242. When the fourth sensor 3 recognizes the presence of the second ply of material it causes the bottom gripper wheels 2 to be actuated. Actuation of bottom gripper wheels 2 causes them to rotate in the direction to move the second ply of material to the right, as seen in FIG. 5. As the second ply of material moves to the right its margin edge approaches bottom or fifth sensor 9. When fifth sensor 9 recognizes the margin edge of the second ply of material 242 it causes the bottom gripper wheels 2 to stop rotating and the feeding wheel 14 is actuated to move the second ply of material toward the stitch forming area.
In this example of the invention two plies of material, a first top ply 142 and a second bottom ply 242, having overlying margin edges are stitched together. However, this invention could utilize additional edge guiding devices in an operation where more plies of material are to be sewed together. Also the invention can be used in a sewing operation in which the margin edges of the plies to be sewed together are parallel but offset from each other. It is also contemplated that for some thick materials or difficult to control materials two or more edge guiding devices could be used in series. For example, several edge guiding devices could be aligned one following another such that there are a plurality of gripper and feeding wheels controlling a ply of material.
As the second ply of material is being moved by the bottom feeding wheel 14 in the direction toward the stitch forming area it encounters bottom ply plate 6 which converges with the undersurface of retractable sensor plate 7 to guide the second ply of material over the leading edge of the feed dogs 162 preventing the leading edge from stumbling or rolling up on the sharp teeth of the feed dog. After the sixth sensor 12 recognizes the leading edge of the second ply of material, the bottom feeding wheel 14 continues to move the second ply of material a predetermined distance Y. When the leading edges of all plies of material, that are to be stitched together, have been advanced distance Y past the last of the sensors, the retractable sensor plate 7 and bottom ply plate 6 are withdrawn and then the pressor foot 164 is lowered and the sewing operation commences. It is important to note that each ply of material is processed independently until it has been located in its proper relationship in the stitch forming area.
As best seen in FIG. 5 the rod 172 of an air cylinder 174 is connected to the right edges of plates 6 and 7. When air cylinder 174 is contracted the plates 6 and 7 are withdrawn from between the overlapped plies of material. The sewing operation is then commenced. The upper and lower edge guiding devices 106 and 108 respectively continue to operate during the sewing operation. The top 4 and bottom 2 gripper wheel function to maintain the first and second plies of material in proper edge alignment while the top 13 and bottom 14 feeding wheels function to feed the material along the line of material feed at a uniform rate that is coordinated with the feed rate of the stitch forming mechanism.
As best seen in FIG. 5 the top surface of the sewing machine includes a throat plate 160 including slots 161 through which feed dog elements 162 project. Throat plate 160 also includes a slot 166 through which the needle 170 moves. In FIG. 6 the needle 170 is illustrated as arcuate shaped however this invention can also be used with sewing machines using straight needles. On the right hand side of the throat plate 160 (FIG. 5) an edge trimmer 176 is shown. The edge trimmer 176 includes a lower fixed knife 178 and an upper moveable trim knife 179. The use of the edge trimmer 176 is optional.
Referring now to FIG. 7 the control system for the device of this invention will be discussed. A synchronizer 302 sends a signal, which indicates the speed at which the stitch forming mechanism of the sewing machine is operating, to the micro processor control system 300. This data is important to the proper operation of edge guiding device because the feeding wheels 13 and 14 must be synchronized with the stitch forming mechanism of the sewing machine. The sensors 3, 5, 9, 10, 11 and 12 each transmit signals to the micro processor control system 300. The signal being transmitted by the sensors changes when a sensor detects the presence of a ply of material. The micro processor is programmed to respond to the changes in the signals that it receives from the sensors by sending operating instructions to various components of the sewing machine and the device for automatically aligning and positioning the plies of material. The micro processor is programmed, for example, in response to a signal from sensor 10 that it has recognized the margin edge of material ply 142, to transmit a signal to the stepper motor 110 to advance or rotate a certain number of steps which will cause the feeder wheel 13 to move the upper ply of material 142 a predetermined distance toward the stitch forming area. This distance can be changed by reprogramming the micro processor. The micro processor control system 300 receives signals from sensors during the sewing operation which it processes and sends appropriate signals to the edge guiding devices to automatically guide the plies of material being stitched and feed them at the appropriate rate.
It is intended that the accompanying drawings and foregoing detailed description is to be considered in all respects as illustrative and not restrictive, the scope of the invention is intended to embrace any equivalents, alternatives, and/or modifications of elements that fall within the spirit and scope of the invention, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A device for aligning the margin and leading edges of plies of material to be sewed and locating the aligned edges at the stitch forming location of a sewing machine. A first sensor for detecting the presence of the work piece and actuating a power driven gripper wheel in response to sensing the work piece. The power driven gripper wheel moves the work piece toward a second sensor that detects the work piece's margin edge and stops the power driven gripper wheel and actuates a power driven feeding wheel that feeds the work piece toward the stitch forming location. A third sensor detects the leading edge of the work piece as it approaches the stitch forming location. Control mechanisms are provided for commencing the sewing operation when the work material is at the stitch forming location. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation in part of application Ser. No. 11/880,363 filed on Jul. 19, 2007.
FEDERALLY SPONSORED RESEARCH
[0002] Not Applicable
SEQUENCE LISTING
[0003] Not Applicable
FIELD OF THE INVENTION
[0004] This invention relates generally to the field of devices that assist physically disabled people to achieve superior results in spite of their physical disability. The instant invention generally relates to sports devices that aid individuals having physical disabilities to participate in sports activities in a superior fashion in spite of their physical disability. This invention more specifically relates to a gripping mitt with a single flap to be utilized in conjunction with paddles for water sports.
BACKGROUND OF THE INVENTION
[0005] Some individuals have impaired hand gripping abilities. The impaired hand gripping ability may be the result of an accident, or nerve damage, or muscle damage or sickness, or arthritis, or carpal tunnel syndrome, or a stroke, or Parkinson's disease, or multiple sclerosis, or overuse of a hand, or other reasons or combinations thereof, etc.
[0006] Many individuals that have impaired hand grips are unable to fully participate in sports related activities because they are unable to adequately grasp handles of sports related devices. Examples of such sports related handles include canoe and/or kayak paddles.
[0007] Often a person with an impaired hand grip may be able to participate in a sports related activity if it were not for the impaired hand grip. The problem of impaired hand grip may be tho only reason a person can not enjoy sports related activities such as paddling a canoe or paddling a kayak.
SUMMARY OF THE INVENTION
[0008] This invention, gripping mitt with flap for water sports, incorporates a water proof mitt that fits over the hand of a user that has difficulty gripping sports related devices such as canoe and/or kayak paddle handles. The mitt is made of a waterproof material such as neoprene. The mitt has a single flap that has a Hook and loop material such as velcro incorporated into the flap. The palm side of the mitt has an opposite “hook and loop” material that holds the single flap in a fastened position. When the gripping mitt with flap is in use, the single flap of the mitt surrounds a paddle handle and holds the paddle so that the user can make paddle strokes. The hook and loop material on the palm of the mitt and the hook and loop material on the single flap provide the gripping force that keeps the hand attached to the paddle.
OBJECTS OF THE INVENTION
[0009] It is an object of the invention to provide a sports gripping mitt with a single flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle.
[0010] It is an object of the invention to provide a sports gripping mitt with a single flap that assists someone with impaired gripping abilities in holding onto a handle of a sports related device such as a canoe paddle.
[0011] It is an object of the invention to provide a sports gripping mitt with a single flap that is easy to place onto and take off a hand of a user.
[0012] It is an object of the invention to provide a sports gripping mitt with a single flap that is relatively easy to manufacture.
[0013] It is an object of the invention to provide a sports gripping mitt with a single flap that would be rugged and reusable.
[0014] It is an object of the invention to provide a sports gripping mitt with a single flap that would not be affected by getting wet and drying out repeatedly.
[0015] It is an object of the invention to provide a sports gripping mitt with a single flap that would be relatively inexpensive to manufacture.
[0016] It is an object of the invention to provide a sports gripping mitt with a single flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle with sufficient gripping forces so that tasks such as paddling a canoe can be done despite the gripping impairment.
[0017] It is an object of the invention to provide a sports gripping mitt with a single flap that is ergonomically designed to assist the user in gripping tasks and also will provide a comfortable fit.
[0018] It is an object of the invention to provide a sports gripping mitt with a single flap that could be easily made to fit many different hand sizes.
[0019] It is an object of the invention to provide a sports gripping mitt with a single flap that can be used on a right hand or a left hand. Separate right hand versions and separate left hand versions are not necessary.
[0020] It is an object of the invention to provide a sports gripping mitt with a single flap that is would enable the user to easily let go of the handle of a sports related device, if so desired.
[0021] It is an object of the invention to provide a sports gripping mitt with a single flap that would enable a variety sports related handles to be securely retained in a users hand even if the user has impaired gripping abilities.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order that the manner in which the above and other objects of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying annexed drawings wherein:
[0023] FIG. 1 is a side view of the sports gripping mitt with flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle.
[0024] FIG. 2 is a top perspective view of a sports gripping mitt with flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. The to dorsal side of the mitt is shown and the user's fingers surround the handle.
[0025] FIG. 3 is a top view of a sports gripping mitt with flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. The dorsal side of the mitt is shown. A wrist tightening strap is in the closed position.
[0026] FIG. 4 is a top view of a sports gripping mitt with flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. The dorsal side of the mitt is shown. A wrist tightening strap is in the open position.
[0027] FIG. 5 is a top view of a sports gripping mitt with flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. The palm side of the mitt is shown. A wrist tightening strap is in the open position.
[0028] The objects and advantages of the invention will become apparent when the drawings are studied in conjunction with reading the following description and also reading the claims.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] In keeping with the requirements of Patent Laws there is described herein below the best mode of the invention that is currently known to the applicant. For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment 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, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0030] With reference now to the drawings, and in particular, to FIGS. 1-5 thereof, the preferred embodiment of the new sports gripping mitt with a single flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. The preferred design embodies the principles and concepts of the present invention and generally designated by the reference number 10 will be described.
[0031] FIG. 1 shown generally at 10 is a side view of the sports gripping mitt with a single flap that assists the wearer in holding onto a handle to of a sports related device such as a canoe paddle. A water proof mitt 12 fits over the hand of a user that has difficulty gripping sports related devices such as canoe and/or kayak paddle handles. The gripping mitt 12 is made of a waterproof material such as neoprene. The neoprene could have a nylon covering on the outside of the mitt as well as the inside of the mitt. Mitt has a dorsal side 13 and a palm side 14 that has hook material 15 . The mitt has a single flap 16 that has loop material 17 . Mitt has a wrist opening 20 for the wrist of a user 21 . The gripping mitt has side stitching 22 . The handle 28 of a paddle is shown with sports gripping mitt 12 with the single flap 16 surrounding the handle 28 . Palm side 14 of mitt 12 has gripping section 29 . When the paddle is in use the hook material 15 on the palm 14 of the gripping mitt 12 and the loop material 17 on the single flap 16 provide the gripping force that keeps the hand attached to the paddle. A wrist tightening strap 30 has hook and loop material 32 and release tab 34 . Mitt 12 has hook and loop material 36 for engaging hook and loop material 32 on tightening strap 30 . Single flap 16 has a quick release tab 16 A.
[0032] FIG. 2 shown generally at 40 is a top side view of the sports gripping mitt with a single flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. A water proof mitt 12 fits over the hand of a user that has difficulty gripping sports related devices such as canoe and/or kayak paddle handles. The gripping mitt 12 has a dorsal side 13 and a palm side 14 that has hook material 15 . The mitt has a single flap 16 that has loop material 17 . Mitt has a wrist opening 20 for the wrist of a user 21 . The gripping mitt has side stitching 22 . The handle 28 of a paddle is shown with sports gripping mitt with flap 12 surrounding the handle 28 . Palm side 14 of mitt 12 has gripping section 29 . When the paddle is in use the hook material 15 on the palm 14 of the gripping mitt 12 and the loop material 17 on the single flap 16 provide the gripping force that keeps the hand attached to the paddle. A wrist tightening strap 30 has hook and loop material 32 and release tab 34 . Mitt 12 has hook material 36 for engaging loop material 32 on tightening strap 30 . Wrist tightening strap 30 is in a tightened position.
[0033] FIG. 3 shown generally at 50 is a top view of the dorsal the sports gripping mitt with flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. A water proof mitt 12 fits over the hand of a user that has difficulty gripping sports related devices such as canoe and/or kayak paddle handles. The gripping mitt 12 is made of a waterproof material such as nylon covered neoprene and has a dorsal side 13 and a palm side (not shown) Mitt has a wrist opening 20 for the wrist of a user. The gripping mitt has side stitching 22 and side stitching 23 . A wrist tightening strap 30 has hook and loop material 32 (not shown) and release tab 34 . Mitt 12 has hook and loop material 36 for engaging hook and loop material 32 (not shown) on tightening strap 30 . Wrist tightening strap 30 is in a tightened position. This embodiment of the gripping mitt has been cut from a single piece of nylon covered material and has folded edge 39 and stitched edges 22 and 23 . Single flap 16 has quick release tab 16 A. Gripping mitt has a single pocket that enclosed the entire hand 51 of a user. The same mitt can be used for a right hand or a left hand. This simplifies the design and manufacturing process.
[0034] FIG. 4 shown generally at 60 is a top view of the dorsal surface 13 of the sports gripping mitt 12 that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. A water proof mitt 12 fits over the hand of a user who has difficulty gripping sports related devices such as canoe and/or kayak paddle handles. The gripping mitt 12 is made of a waterproof material such as nylon covered neoprene and has a dorsal side 13 and a palm side (not shown.) Mitt has a wrist opening 20 for the wrist of a user. The gripping mitt has side stitching 22 and side stitching 23 . A wrist tightening strap 30 has hook and loop material 32 and release tab 34 . Mitt 12 has hook and loop material 36 for engaging hook and loop material 32 tightening strap 30 . Wrist tightening strap 30 is in an unfastened position. Mitt 12 has a slit 35 down the side of the wrist opening 20 to allow greater ease of donning the mitt 12 . This embodiment of the gripping mitt has been cut from a single piece of nylon covered material and has folded edge 39 to and stitched edges 22 . Product names could be printed or stitched on to various parts of the mitt. An example might be WaterSport GripMitt 61 . Company names could be printed or stitched on to various parts of the mitt also. An example might be Island Outfitters 62 .
[0035] FIG. 5 shown generally at 70 is a top view of the palm side of the sports gripping mitt with a single flap that assists the wearer in holding onto a handle of a sports related device such as a canoe paddle. A water proof mitt 12 fits over the hand of a user that has difficulty gripping sports related devices such as canoe and/or kayak paddle handles. The gripping mitt 12 is made of a waterproof material such as nylon covered neoprene and has a dorsal side 13 (not shown) and a palm side 14 that has hook and loop material 15 . The mitt has flap 16 that has hook and loop material 17 . Mitt has a wrist opening 20 for the wrist of a user. The gripping mitt has side stitching 22 . When the paddle is in use the hook and loop material 15 on the palm 14 of the gripping mitt 12 and the hook and loop material 17 on the flap 16 provide the gripping force that keeps the hand attached to the paddle. A wrist tightening strap 30 has hook and loop material 32 (not shown) and release tab 34 . Wrist tightening strap is in an unfastened position. Palm side 14 of mitt 12 has gripping section 29 and an access aperture 71 . Access aperture 71 is located on the gripping section 29 of palm side 14 of mitt 12 . The gripping section 29 is made of a tacky or gripping material on the surface to prevent the paddle shaft from slipping or rotating while being gripped. Gripping section 29 can be made of a separate material and fastened to the palm area by adhesives or by stitching. Gripping section could be made from various materials such as “Dycem” or an non-covered neoprene. Access aperture 17 enables a user to get into the inside of the mitt 12 if so desired. A palm side access opening is important because often someone that has impaired use of a hand has no muscular control of the fingers. Therefore when a gripping mitt is pulled over an impaired hand the fingers will be folded over toward that persons wrist. If the users fingers are folded over, the mitt cannot function properly. A person with one impaired hand can use their other hand and fingers to reach through the palm side access opening, into the inside of the palm side of the mitt to straighten out the bent over fingers so that those fingers are in the proper straightened out position inside the mitt. Alternately, another person could use their hand and fingers to reach through the palm side access opening, into the inside of the palm side of the mitt to straighten out the bent over fingers of a user so that a users fingers are in the proper straightened out position inside the mitt. Access opening could be different lengths for different applications. A three inch long slit would Mitt 12 has a slit 35 down the side of the wrist opening 20 to allow greater ease of donning the mitt 12 . This embodiment of the gripping mitt has been cut from a single piece of nylon covered material and has folded edge 39 and stitched edges 22 . Mitt 12 has an opening finger tip end drain opening 72 to allow water to drain out of the mitt finger tip end of the mitt. Finger tip drain opening 72 could be different sizes. Finger tip drain opening 72 could be as long as the width of said single flap 16 which is 2 and ¼ inches wide. Single flap 16 has a quick release tab 16 A thereon. There could be numerous sizes for mitts with single flaps. A mitt length could be approximately 10 inches long and 6 inches wide. Single flap could be 2 and ¼ wide and 6 inches long. Gripping section could be 5 inches wide and 3 and ½ inches tall. Access opening could be many lengths. A length of 3 inches for an access opening would seem to be a minimum length. However, and access opening could be less than 3 inches if so desired.
[0036] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap is unique and clearly provides a simple solution to an impaired grip problem.
[0037] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap assists the wearer in holding onto a handle of a sports related device such as a canoe paddle.
[0038] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap assists someone with impaired gripping abilities in holding onto a handle of a sports related device such as a canoe paddle.
[0039] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap that is easy to place onto and take off a hand of a user.
[0040] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap that is relatively easy to manufacture.
[0041] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap would be rugged and reusable.
[0042] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap would not be affected by getting wet and drying out repeatedly.
[0043] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap would be relatively inexpensive to manufacture.
[0044] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap assists the wearer in holding onto a handle of a sports related device such as a canoe paddle with sufficient gripping forces so that tasks such as paddling a canoe can be done despite the gripping impairment.
[0045] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap is ergonomically designed to assist the user in gripping tasks and also will provide a comfortable fit.
[0046] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap could be easily made to fit many different hand sizes.
[0047] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap that can be used on a right hand or a left hand. Separate right hand versions and separate left hand versions are not necessary.
[0048] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap would enable the user to easily let go of the handle of a sports related device if so desired.
[0049] It should be very clear from the drawings and the above description that this sports gripping mitt with a single flap would enable many sports related handles to be securely retained in a users hand even if the user has impaired gripping abilities.
[0050] This invention having been described in its presently contemplated best mode, it is clear that it is susceptible to numerous, variations, modifications, modes and embodiments within the ability of those skilled in the art and without departing from the true spirit and scope of the novel concepts or principles of this invention.
[0051] Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. It should be understood that the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. The invention is capable of other embodiments and of being practiced and carried out in various ways. As such, 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. Accordingly, the scope of the invention is defined by the scope of the following claims. | This invention, gripping mitt with single flap for water sports, incorporates a water proof mitt that fits over the hand of a user that has difficulty gripping sports related devices such as canoe and/or kayak paddle handles. The mitt is made of a waterproof material such as neoprene. The mitt has a single flap that has a hook and loop material such as velcro incorporated into the single flap. The palm side of the mitt has an opposite “hook and loop” material that holds the single flap in a fastened position. When the gripping mitt with single flap is in use, the single flap of the mitt surrounds a paddle handle and holds the paddle so that the user can make paddle strokes. The hook and loop material on the palm of the mitt and the hook and loop material on the single flap provide the gripping force that keeps the hand attached to the paddle. The gripping mitt with flap has additional innovative features. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a control system and method of a hybrid vehicle which is driven by an engine and an electric motor, and in particular, to a system and a method for preventing a decrease of the remaining battery charge while driving in a traffic jam.
2. Description of the Related Art
Conventionally, a hybrid vehicle having not only an engine but also an electric motor as the drive source is known.
As a hybrid vehicle, a parallel hybrid vehicle is known that uses an electric motor as an auxiliary drive source for assisting the engine output. In the parallel hybrid vehicle, typically, operation of the engine is assisted using the electric motor during the accelerating operation, while during the decelerating operation, the battery and the like are charged via a regenerating operation, that is, “deceleration regeneration” is performed. According to various control operations including the above, the remaining battery charge (called a “SOC (state of charge)”, hereinafter) of the battery is maintained while also satisfying the driver's demands. An example thereof is disclosed in Japanese Unexamined Patent Application, First Publication, No. Hei 7-123509.
When such a conventional parallel hybrid vehicle drives at a medium or high speed, sufficient regeneration energy can be obtained during deceleration. However, if the vehicle repeatedly starts and stops at a low vehicle speed, problems relating to the power management may occur.
That is, when the vehicle repeatedly starts and stops, decelerating operation starts before the vehicle speed becomes sufficiently high; thus, sufficient regeneration energy cannot be stored. During a traffic jam or the like in which each vehicle has to repeatedly start and stop at a low vehicle speed, sufficient charge (obtained by deceleration regeneration) cannot be obtained.
SUMMARY OF THE INVENTION
In consideration of the above circumstances, an objective of the present invention is to provide a control system and method applied to a hybrid vehicle, by which an excessive decrease of the remaining battery charge can be prevented while driving in a traffic jam.
Therefore, the present invention provides a control system of a hybrid vehicle, wherein:
said hybrid vehicle comprises:
an engine (for example, an engine E in the following embodiment) and a motor (for example, an motor M in the following embodiment) for outputting force for driving the vehicle;
a battery device (for example, a battery 3 in the following embodiment); and
a charging device (for example, the motor M in the following embodiment) for charging the battery device, and
said control system comprising:
a remaining battery charge detecting section (for example, a battery ECU 31 in the following embodiment) for detecting the remaining battery charge (for example, remaining battery charge QBAT in the following embodiment) of the battery device;
a traffic-jam drive determining section for determining whether the vehicle is driving in a traffic jam (refer to step S 105 in the following embodiment); and
a control section for making the charging device charge the battery device if the remaining battery charge of the battery device, detected by the remaining battery charge detecting section, is below a first predetermined value (for example, un upper limit #QBJAM in the following embodiment), and if it is determined by the traffic-jam drive determining section that the vehicle is driving in a traffic jam.
The present invention also provides a control method of a hybrid vehicle having the above structure, comprising the steps of:
detecting the remaining battery charge of the battery device;
determining whether the vehicle is driving in a traffic jam; and making the charging device charge the battery device if the detected remaining battery charge of the battery device is below a first predetermined value, and if it is determined that the vehicle is driving in a traffic jam.
Accordingly, while the battery device is charged, no power is supplied to the motor, so that it is possible to prevent an excessive decrease of the remaining battery charge of the battery device.
In a typical example, the traffic-jam drive determining section comprises:
a maximum speed detecting section (for example, an FIECU 11 in the following embodiment) for detecting a maximum vehicle speed during a single driving operation (or movement) from the vehicle start to stop (for example, a maximum vehicle speed DRVMAX in the following embodiment); and
a throttle opening-degree detecting section (for example, a throttle opening-degree sensor S 6 in the following embodiment) for detecting a degree of throttle opening (for example, the degree of throttle opening TH in the following embodiment) of the engine, and
the traffic-jam drive determining section determines that the vehicle is driving in a traffic jam if the maximum vehicle speed during a single driving operation is equal to or below a predetermined value (for example, an upper limit vehicle speed #VJAMST in the following embodiment), and if the degree of throttle opening is equal to or below a predetermined value (for example, an upper limit degree #THJAM in the following embodiment).
Similarly, the step, of determining whether the vehicle is driving in a traffic jam may comprise the steps of:
detecting a maximum vehicle speed during a single driving operation from the vehicle start to stop;
detecting a degree of throttle opening of the engine; and
determining that the vehicle is driving in a traffic jam if the maximum vehicle speed during a single driving operation is equal to or below a predetermined value, and if the degree of throttle opening is equal to or below a predetermined value.
Accordingly, if it is determined that the vehicle is driving in a traffic jam as described above, and if the remaining battery charge of the battery device is below the first predetermined value, the battery device is charged and thus it is possible to prevent an excessive decrease of the battery device.
In another typical example, the traffic-jam drive determining section comprises:
a maximum speed detecting section for detecting a maximum vehicle speed during a single driving operation from the vehicle start to stop, and
the traffic-jam drive determining section determines that the vehicle is driving in a traffic jam if the maximum vehicle speed during a single driving operation is equal to or below a predetermined value, and if the remaining battery charge of the battery device, detected by the remaining battery charge detecting section, is equal to or below a second predetermined value (for example, remaining battery charge #QBJAMST in the following embodiment) which is smaller than the first predetermined value.
Similarly, the step of determining whether the vehicle is driving in a traffic jam may comprises the steps of:
detecting a maximum vehicle speed during a single driving operation from the vehicle start to stop; and
determining that the vehicle is driving in a traffic jam if the maximum vehicle speed during a single driving operation is equal to or below a predetermined value, and if the detected remaining battery charge of the battery device is equal to or below a second predetermined value which is smaller than the first predetermined value.
According to the above conditions, it can be determined that the remaining battery charge of the battery device has been excessively consumed regardless of the degree of throttle opening, and the battery device can be immediately charged, thereby much more reliably preventing an excessive decrease of the remaining battery charge.
After it is determined that the vehicle is driving in a traffic jam according to any method as explained above, the traffic-jam drive determination may be released if the vehicle speed becomes equal to or above a predetermined value, or if the vehicle speed is below a predetermined value and the degree of throttle opening becomes equal to or above a predetermined value. Accordingly, the traffic-jam drive determination can be quickly released immediately after it is determined that the vehicle has been escaped from the traffic jam.
In the above structure, preferably, the motor also functions as the charging device, and the battery device stores energy generated using the motor as a generator driven by the engine, and energy regenerated via a regenerating operation performed by the motor when the vehicle is decelerating. In this case, the operation of charging the battery device can be reliably performed because the motor which functions as the charging device stops the original motor operation. In addition, the space in the engine room can be effectively used.
In addition, the control section may prohibit or restrict the operation of outputting force by the motor if the remaining battery charge is below the first predetermined value, and if it is determined that the vehicle is driving in a traffic jam.
Similarly, in the control method, the operation of outputting force by the motor may be prohibited or restricted if the remaining battery charge is below the first predetermined value, and if it is determined that the vehicle is driving in a traffic jam.
Furthermore, the control section may set the amount of the charge performed by the charging device to a high charge level if the remaining battery charge is below the first predetermined value, and if it is determined that the vehicle is driving in a traffic jam.
Similarly, in the control method, the amount of the charge performed by the charging device may be set to a high charge level if the remaining battery charge is below the first predetermined value, and if it is determined that the vehicle is driving in a traffic jam.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing the general structure of the hybrid vehicle in an embodiment according to the present invention.
FIG. 2 is a flowchart showing the operation for determining the driving state in a traffic jam.
FIG. 3 is also a flowchart showing the operation for determining the driving state in a traffic jam.
FIG. 4 is a flowchart showing the operation for determining the motor operation mode.
FIG. 5 is also a flowchart showing the operation for determining the motor operation mode.
FIG. 6 is a flowchart showing the operation of the idle mode.
FIG. 7 is also a flowchart showing the operation of the idle mode.
FIG. 8 is a flowchart showing the operation of the idle charge mode.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, an embodiment of the present invention will be explained referring to the figures.
FIG. 1 is a block diagram illustrating a parallel hybrid vehicle in which the embodiment of the present invention is applied, and the vehicle comprises an engine E and an electric motor M. The driving force generated by both the engine E and electric motor M is transmitted via automatic or manual transmission T to the driving wheels (here, front wheels) Wf. At the time of the deceleration of the hybrid vehicle, the driving force is transmitted from the driving wheels Wf to the electric motor M, the electric motor M functions as a generator for generating what is termed regenerative braking force, that is, the kinetic energy of the vehicle body is recovered and stored as electric energy.
The driving of the motor M and the regenerating operation of the motor M are controlled by a power drive unit 2 according to control commands from a motor ECU 1 . A high voltage battery 3 for sending and receiving electric energy to and from the motor M is connected to the power drive unit 2 . The battery 3 includes a plurality of modules connected in series, and in each module, a plurality of cells are connected in series. The hybrid vehicle includes a 12-V auxiliary battery 4 for driving various accessories. The auxiliary battery 4 is connected to the battery 3 via a downverter 5 . The downverter 5 , controlled by an FIECU 11 , reduces the voltage from the battery 3 so as to charge the auxiliary battery 4 .
The FIECU 11 controls, in addition to the motor ECU 1 and the downverter 5 , a fuel supply amount controller 6 for controlling the amount of fuel supplied to the engine E, a starter motor 7 , and ignition timing, etc. Therefore, the FIECU 11 receives (i) a signal from a speed sensor S 1 for detecting vehicle speed V based on the rotation speed of the drive shaft of transmission T, (ii) a signal from an engine (rotational) speed sensor S 2 for detecting engine (rotational) speed NE, (iii) a signal from a shift position sensor S 3 for detecting the shift position of the transmission T, (iv) a signal from a brake switch S 4 for detecting operation of a brake pedal 8 , (v) a signal from a clutch switch S 5 for detecting the operation of a clutch pedal 9 , (vi) a signal from a throttle opening-degree sensor S 6 for detecting the degree of throttle (valve) opening TH, and (vii) a signal from an air-intake passage pressure sensor S 7 for detecting the air-intake passage (negative) pressure PB.
In FIG. 1, a CVTECU 21 controls the CVT (continuously variable transmission), a battery ECU 31 protects the battery 3 , and calculates the state of charge (remaining battery charge) SOC of the battery 3 .
This hybrid vehicle can enter various control modes, such as an “acceleration mode”, a “cruise mode”, a “deceleration mode”, an “idle stop mode”, and an “idle mode”. Referring to the flowchart shown in FIGS. 4 and 5, the process for determining the above four motor control modes will be explained.
First, in step S 101 , it is determined whether the value of flag F_AT is 1. The flag F_AT is provided for determining whether the transmission is CVT (continuous variable transmission) or MT (manual transmission). If the result of the determination in step S 101 is “NO”, that is, if it is determined that the vehicle employs an MT, the operation proceeds to step S 102 . If the result of the determination in step S 101 is “YES”, that is, if it is determined that the vehicle employs a CVT, the operation jumps to step S 116 , where it is determined whether the value of flag F_ATNP is 1. The flag F_ATNP is provided for determining the in-gear state of CVT. If the result of the determination in step S 116 is “NO”, that is, if it is determined that the CVT is in the in-gear state, then in step S 117 , it is further determined whether the value of flag F_VSWB is 1. Here, the flag F_VSWB is provided for determining whether the switch back operation is currently executed (that is, the shift lever is being operated). If the result of the determination in step S 117 is “NO”, that is, if it is determined that the switch back is currently not being executed, then the operation proceeds to step S 104 . If the result of the determination in step S 117 is “YES”, that is, if it is determined that the switch back is currently being executed, then the operation jumps to step S 131 , where the control mode is switched to the idle mode, and the control operation of this flow is terminated.
If the result of the determination in step S 116 is “YES”, that is, if it is determined that the CVT is in the N (neutral) or P (parking) range, the operation jumps to step S 133 , where it is determined whether the value of flag F_FCMG is 1. This flag F_FCMG is provided for determining whether the control of stopping the engine is being performed. If the result of the determination in step S 133 is “NO”, the operation proceeds to step S 131 , while if the result of the determination in step S 133 is “YES”, then the operation proceeds to step S 134 . In the step S 134 , control suitable for the idle stop mode is performed, and the control of this flow is completed. In the idle stop mode, the engine is stopped under specific conditions.
In step S 102 , it is determined whether the value of flag F_NSW is 1. The flag F_NSW is provided for determining whether a neutral position is currently selected. If the result of the determination in step S 102 is “YES”, that is, if it is determined that a neutral position is currently selected, then the operation jumps to step S 133 .
If the result of the determination in step S 102 is “NO”, that is, if it is determined that the current state is the in-gear state, then the operation proceeds to step S 103 , where it is determined whether the value of flag F_CLSW is 1. The flag F_CLSW is provided for determining whether the clutch is currently disengaged. If the result of the determination is “YES”, that is, if it is determined that the clutch is currently disengaged, then the operation jumps to step S 133 .
If the result of the determination in step S 103 is “NO”, that is, if it is determined that the clutch is being engaged, then the operation proceeds to step S 104 . In step S 104 , it is determined whether the current remaining battery charge (i.e., the current state of charge of the battery) QBAT of battery 3 is equal to or above an upper limit #QBJAM (e.g., 30%) of the remaining battery charge. Here, the upper limit #QBJAM is predetermined for determining whether the determination relating to driving in a traffic jam is executed, and #QBJAM is predetermined in consideration of hysteresis. If the result of the determination is “YES”, that is, if the current remaining battery charge QBAT of battery 3 is equal to or above the upper limit #QBJAM of the remaining battery charge, then the operation proceeds to step S 106 .
If the result of the determination in step S 104 is “NO”, that is, if the current remaining battery charge QBAT of battery 3 is not equal to or above an upper limit #QBJAM of the remaining battery charge, then the operation proceeds to step S 105 , where it is determined whether the value of flag F_JAMST is 1. This flag F_JAMST is provided for determining whether the vehicle is driving in a traffic jam. The determination whether the vehicle is driving in a traffic jam will be explained later in detail. If the result of the determination in step S 105 is “YES”, that is, if it is determined that the vehicle is driving in a traffic jam, then the operation proceeds to step S 133 . That is, if the remaining battery charge QBAT of battery 3 is below the upper limit #QBJAM, and if it is determined that the vehicle is driving in a traffic jam, then control suitable for the idle or idle stop mode is performed (see steps S 131 and S 134 ), so that the operation of outputting force by the motor is prohibited.
If the result of the determination in step S 105 is “NO”, that is, if it is determined that the vehicle is not driving in a traffic jam, then the operation proceeds to step S 106 . In step S 106 , it is determined whether the value of flag F_THIDLMG is 1.
The flag F_THIDLMG is provided for determining the idle state. If the result of the determination is “NO”, that is, if it is determined that the degree of throttle opening is minimum (i.e., completely closed), then the operation jumps to step S 118 . If the result of the determination in step S 106 is “YES”, that is, if it is determined that the throttle is not completely closed, then the operation proceeds to step S 107 , where it is determined whether the value of flag F_MAST is 1. This flag F_MAST is provided for determining whether the motor is assisting the motor output.
If the result of the determination in step S 107 is “NO”, the operation jumps to step S 118 , while if the result of the determination in step S 107 is “YES”, then the operation proceeds to step S 108 .
In step S 118 , it is determined whether the value of flag F_AT (for determining the MT/CVT) is 1. If the result of the determination is “NO”, that is, if it is determined that the present, vehicle employs an MT, then the operation proceeds to step S 120 . If the result of the determination in step S 118 is “YES”, that is, if it is determined that the present vehicle employs a CVT, then the operation proceeds to step S 119 . In step S 119 , it is determined whether the value of flag F_ATPR is 1. This flag F_ATPR is provided for determining whether the current position of the CVT is a reverse position. If the result of the determination is “YES”, that is, if it is determined that the current position is the reverse position, then the operation jumps to step S 131 . If the result of the determination in step S 119 is “NO”, that is, if it is determined that the current position is another position, then the operation proceeds to step S 120 .
In step S 108 , it is determined whether the value of flag F_AT (for determining the MT/CVT) is 1. If the result of the determination is “NO”, that is, if it is determined that the present vehicle employs an MT, then the operation proceeds to step S 110 , where regeneration operation is executed during acceleration under some conditions. The operation then proceeds, to step S 111 . In step S 111 , it is determined whether the value of flag F_ACCRGN is 1. This flag F_ACCRGN is provided for determining whether the regeneration is being executed during acceleration. If the result of the determination is “YES”, that is, if it is determined that regeneration is being executed during acceleration, then the operation proceeds to step S 113 . If the result of the determination in step S 111 is “NO”, that is, if it is determined that regeneration is not currently executed during acceleration, then the operation proceeds to step S 112 , where subtraction of a final charge command value REGENF is executed. Here, the final charge command value REGENF indicates the amount of charge to be executed, and value 0 indicates charge is not executed.
The operation then proceeds to step S 113 , where it is determined whether the final charge command value REGENF is equal to or below 0. If it is determined that the final charge command value REGENF is larger than 0, then the operation of the present flow is completed. If it is determined, in step S 113 , that the final charge command value REGENF is equal to or below 0, then the operation proceeds to step S 114 , where control suitable for the acceleration mode is executed. In the next step S 115 , it is determined whether the value of flag F_ACCAST is 1. This flag F_ACCAST is provided for determining whether the engine assisting operation is permitted. If the result of the determination is “YES”, then the operation of this flow is completed. If the result of the determination in step S 115 is “NO”, that is, if the value of flag F_ACCAST is 0, then the operation proceeds to step S 120 . Here, in the above acceleration mode, the engine driving operation is assisted by using motor M.
If the result of the determination in step S 108 is “YES”, that is, if it is determined that the vehicle employs a CVT, then the operation proceeds to step S 109 , where it is determined whether the value of flag F_BKSW is 1. This flag F_BKSW is provided for determining whether the brake is being depressed. If the result of the determination is “YES”, that is, if it is determined that the brake is being depressed, then the operation jumps to step S 120 . If the result of the determination in step S 109 is “NO”, that is, if it is determined that the brake is not currently being depressed, then the operation proceeds to step S 110 .
In step S 120 , it is determined whether vehicle speed VP (detected for controlling the engine) is 0. If the result of the determination is “YES”, that is, if it is determined that the vehicle speed VP is 0, then the operation jumps to step S 133 . If the result of the determination in step S 120 is “NO”, that is, if it is determined that the vehicle speed VP is not 0, then the operation proceeds to step S 121 . In step S 121 , it is determined whether the value of the flag F_FCMG is 1.
If the result of the determination in step S 121 is “NO”, then the operation proceeds to step S 122 . If the result of the determination in step S 121 is “YES”, that is, if it is determined that the relevant flag value is 1, then the operation jumps to step S 134 .
In step S 122 , the engine speed NE is compared with a lower limit engine speed #NERGNLx predetermined for the cruise/deceleration mode. Here, the “x” in #NERGNLx indicates each gear, that is, the lower limit engine speed is predetermined for each gear in consideration of hysteresis.
If it is determined, in step S 122 , that engine speed NE≦lower limit engine speed #NERGNLx, that is, if it is determined that the engine speed is relatively low, then the operation jumps to step S 131 . If it is determined, in step S 122 , that engine speed NE>lower limit engine speed #NERGNLx, that is, if it is determined that the engine speed is relatively high, then the operation proceeds to step S 123 .
In step S 123 , it is determined whether the above vehicle speed VP is equal to or below a lower limit vehicle speed #VRGNBK which a predetermined value provided for determining the brake operation in the deceleration mode. If the result of the determination is “YES”, then the operation jumps to step S 126 , while if the result of the determination in step S 123 is “NO”, then the operation proceeds to step S 124 .
In step S 124 , it is determined whether the value of the above-explained flag F_BKSW for determining the brake state is 1. If the result of the determination in step S 124 is “YES”, that is, if it is determined that the brake is being depressed, then the operation proceeds to step S 125 . If the result of the determination in step S 124 is “NO”, that is, if it is determined that the brake is not currently depressed, the operation jumps to step S 126 .
In step S 125 , it is determined whether the value of flag F_THIDLMG is 1. As explained above, this flag F_THIDLMG is provided for determining the idle state. If the result of the determination is “NO”, that is, if it is determined that the throttle is completely closed, then the operation jumps to step S 130 (where the control suitable for the deceleration mode is performed), and in the next step S 132 , the above-explained regeneration operation, executed under some conditions during acceleration, is performed, and the control operation of this flow is completed. In the deceleration mode, regenerative braking operation using motor M is executed. If the result of the determination in step S 125 is “YES”, that is, if it is determined that the throttle is not completely closed, then the operation proceeds to step S 126 .
In step S 126 , it is determined whether the value of flag F_FC is 1. This flag F_FC is provided for determining whether the fuel cut-off is being executed. If the result of the determination is “YES”, that is, if it is determined that the fuel cut-off is being executed, then the operation jumps to step S 130 . If the result of the determination in step S 126 is “NO”, then the operation proceeds to step S 127 , where subtraction of a final assist command value ASTPWRF is performed. Here, the final assist command value ASTPWRF indicates power to provide assistance, and value 0 indicates the assisting operation is not executed. In the next step S 128 , it is determined whether the final assist command value ASTPWRF is equal to or below 0. If it is determined that ASTPWRF is equal to or below 0, then the operation proceeds to step S 129 , where control suitable for the cruise mode is performed. In this cruise mode, motor M is not driven, and the vehicle is driven using the driving force of engine E. The operation then jumps to step S 132 . If it is determined, in step S 128 , that the final assist command value ASTPWRF is larger than 0, then the control operation of this flow is completed.
Accordingly, (i) if it is determined that the remaining battery charge is below #QBJAM (i.e., “NO” in step S 104 ), and (ii) if the value of flag F_JAMST (for determining whether the vehicle is driving in a traffic jam) is 1 (i.e., “YES” in step S 105 ), then it is determined that the energy charged in battery 3 has decreased due to driving in a traffic jam. Therefore, while the value of flag F_FCMG is 1 under these conditions, the control operation of the idle mode is selected and started so as to charge battery 3 .
Determination in Driving in a Traffic Jam
With reference to FIGS. 2 and 3, the operation for determining whether the vehicle is driving in a traffic jam will be explained.
First, in step S 001 , it is determined whether the vehicle is currently in an operation mode relating to a damage of the engine or motor (including the relevant ECU). If the result of the determination is “YES”, that is, if it is determined that the vehicle is in such a damage mode of the engine or motor, then the operation jumps to step S 018 , where the value of flag F_THJAM is set to 0. This flag F_THJAM is provided for indicating the degree of throttle opening (used for determining the driving state in a traffic jam). The operation then proceeds to step S 021 . In step S 021 , the value of the flag F_JAMST is set to 0, and the operation proceeds to step S 022 .
If the result of the determination in step S 001 is “NO”, that is, if it is determined that the vehicle is not in an operation mode relating to a damage of the engine or motor (including the relevant ECU), then the operation proceeds to step S 002 . In the step S 002 , it is determined whether the value of flag F_VJAMIGST is 1 after the ignition is switched on (from the OFF state). Here, the flag F_VJAMIGST is provided for starting the determination of driving in a traffic jam. If the result of the determination is “YES”, that is, if it is determined that the value of the flag F_VJAMIGST is 1, then the operation proceeds to step S 005 .
If the result of the determination in step S 002 is “NO”, that is, if it is determined that the value of flag F_VJAMIGST is 0, then the operation proceeds to step S 003 , where it is determined whether the value of the current vehicle speed VP is equal to or below a lower limit vehicle speed #VJAMIGST (e.g., 20 km/h) after the ignition is switched on (from the OFF state). Here, the lower limit vehicle speed #VJAMIGST is predetermined for determining whether the determination about driving in a traffic jam is started. If the result of the determination is “NO”, that is, if it is determined that the current vehicle speed VP is larger than #VJAMIGST, then the operation proceeds to step S 004 .
If the result of the determination in step S 003 is “YES”, that is, if it is determined that the current vehicle speed VP is equal to or below #VJAMIGST, then the operation jumps to step S 018 , where the value of the flag F_THJAM for indicating the degree of throttle opening (used for determining driving in a traffic jam) is set to 0. The operation then proceeds to step S 021 , where the value of the flag F_JAMST (for determining whether the vehicle is driving in a traffic jam) is set to 0. The operation then proceeds to step S 022 , where the value of flag F_JAMCHK is set to 1. Here, the flag F_JAMCHK is provided for indicating the execution of the determination about driving in a traffic jam.
In step S 004 , the value of the flag F_VJAMIGST is set to 1, then the operation proceeds to step S 005 , where it is determined whether the current vehicle speed VP is equal to or below an upper value #VJAMST (e.g., 5 km/h). This upper value #VJAMST is a predetermined value provided for executing the determination about driving in a traffic jam, and this value is predetermined in consideration of hysteresis. If the result of the determination is “YES”, that is, if the current vehicle speed VP is equal to or below the upper value #VJAMST, then the operation proceeds to step S 015 . The set value 1 of flag F_VJAMIGST (set in step S 004 ) is maintained until the ignition is switched off.
If the result of the determination in step S 005 is “NO”, that is, if the current vehicle speed VP is larger than the upper value #VJAMST, then the operation proceeds to step S 006 , where it is determined whether the value of flag F_JAMCHK (for indicating the execution of the determination about driving in a traffic jam) is 1. If the result of the determination is “NO”, that is, if it is determined that the value of flag F_JAMCHK is 0, then the operation proceeds to step S 009 .
If the result of the determination in step S 006 is “YES”, that is, if it is determined that the value of the flag F_JAMCHK is 1, then the operation proceeds to step S 007 , where a maximum vehicle speed DRVMAX during a single driving operation (or mevement) from start to stop is set to 0. The operation then proceeds to step S 008 . In step S 008 , the value of flag F_JAMCHK (for executing the determination about driving in a traffic jam) is set to 0, then the operation proceeds to step S 009 .
In step S 009 , it is determined whether the current vehicle speed is equal to or above the maximum vehicle speed DRVMAX during a single driving operation from start to stop. If the result of the determination is “NO”, that is, if the current vehicle speed is smaller than the maximum vehicle speed DRVMAX (during a single driving operation), then the DRVMAX is not updated and the operation proceeds to step S 011 .
If the result of the determination in step S 009 is “YES”, that is, if the current vehicle speed VP is equal to or above the maximum vehicle speed DRVMAX (during a single driving operation), then the operation proceeds to step S 010 , where the DRVMAX is set to the current vehicle speed VP and the operation proceeds to step S 011 .
In step S 011 , it is determined whether the current vehicle speed VP is equal to or above a lower limit vehicle speed #VJAMC (e.g., 20 km/h) for determining whether the vehicle is in a normally driving state. If the result of the determination is “YES”, that is, if the current vehicle speed VP is equal to or above the lower limit vehicle speed #VJAMC, then the operation proceeds to step S 013 .
If the result of the determination in step S 011 is “NO”, that is, if the current vehicle speed VP is below the lower limit vehicle speed #VJAMC, then the operation proceeds to step S 012 . In the step S 012 , it is determined whether the current degree TH of throttle opening is equal to or above a lower limit degree #THJAMC (e.g., 20 degrees) of throttle opening in normal driving. If the result of the determination is “NO”, that is, if the current degree TH of throttle opening is below the lower limit degree #THJAMC, then the operation proceeds to step S 014 .
If the result of the determination in step S 012 is “YES”, that is, if the current degree TH of throttle opening is equal to or above the lower limit degree #THJAMC of throttle opening in normal driving, then the operation proceeds to step S 013 . In step S 013 , the value of the flag F_JAMST is set to 0, then the operation proceeds to step S 014 . In the step S 014 , the value of the above-explained flag F_THJAM is set to 1. The operation of this flow is then completed.
If the result of the determination in step S 005 is “YES”, that is, if the current vehicle speed VP is equal to or below #VJAMST, then the operation proceeds to step S 015 . In the step S 015 , it is determined whether the above-explained maximum vehicle speed DRVMAX (during a single driving operation from start to stop) is equal to or above an upper limit vehicle speed #VJAM (e.g., 18 km/h) for determining driving in a traffic jam. If the result of the determination is “YES”, that is, if the maximum vehicle speed DRVMAX is equal to or above the upper limit vehicle speed #VJAM for determining driving in a traffic jam, then the operation proceeds to step S 018 .
If the result of the determination in step S 015 is “NO”, that is, if the maximum vehicle speed DRVMAX is not equal to or above the upper limit vehicle speed #VJAM, more specifically, if the vehicle drives at a speed by which the vehicle may be driving in a traffic jam, then the operation proceeds to step S 016 . In the step S 016 , it is determined whether the current remaining battery charge QBAT is equal to or below a predetermined value #QBJAMST (e.g., 18%). This value #QBJAMST is predetermined in consideration of hysteresis. If the result of the determination is “YES”, that is, if the current remaining battery charge QBAT is equal to or below the predetermined value #QBJAMST, then the operation proceeds to step S 020 .
If the result of the determination in step S 016 is “NO”, that is, if the current remaining battery charge QBAT is larger than the predetermined value #QBJAMST, then the operation proceeds to step S 017 . In the step S 017 , it is determined whether the current degree TH of throttle opening is equal to or below an upper limit degree THJAM (e.g., 20 degrees) of throttle opening for determining driving in a traffic jam. If the result of the determination is “NO”, that is, if the current degree TH of throttle opening is above the upper limit degree THJAM, then the operation proceeds to step S 018 .
If the result of the determination in step S 017 is “YES”, that is, if—the current degree TH of throttle opening is equal to or below the above upper limit degree THJAM, then the operation proceeds to step S 019 , where the value of the flag F_THJAM (for indicating the degree of throttle opening used for determining the driving state in a traffic jam) is set to 1. The operation then proceeds to step S 020 , where the value of flag F_JAMST is set to 1, and then the operation proceeds to step S 022 .
Therefore, if the maximum vehicle speed DRVMAX (during a single driving operation) is smaller than #VJAM, and if the degree of throttle opening is equal to or below #THJAM, then it is estimated that the vehicle is driving in a traffic jam. In this case, the value of flag F_JAMST (for determining the driving state in a traffic jam) is set to 1 so as to prevent unnecessarily consumption of the power (i.e., energy) charged in battery 3 while driving in a traffic jam.
Additionally, when the maximum vehicle speed DRVMAX (during a single driving operation) is smaller than #VJAM, if the remaining battery charge of battery 3 is equal to or below #QBJAMST (corresponding to the second predetermined value in the present invention), too much of the remaining battery charge of battery 3 has been consumed. Therefore, in this case, the determination about driving in a traffic jam is performed by only referring to the vehicle speed, and the value of flag F_JAMST is set to 1 so as to immediately regain the charged energy.
Idle Mode
Below, the control of the idle mode will be explained with reference to the flowchart shown in FIGS. 6 and 7.
In step S 200 , it is determined whether the current mode is the idle mode. If it is determined that the current mode is the idle mode, then the operation proceeds to step S 202 . If it is determined, in step S 200 , that the current mode is another mode, then in step S 201 , a final idle charge command value IDLRGNF is set to 0, and the operation proceeds to step S 202 . Accordingly, if the idle mode starts by shifting from another mode (other than the idle mode), the initial amount of the idle charge (i.e., the charge operation in the idle mode) is set to 0.
In step S 202 , it is determined whether the value of the flag F_JAMST for determining the driving state in a traffic jam is 1. If the result of the determination is “YES”, that is, if it is determined that the vehicle is driving in a traffic jam, then the operation proceeds to step S 217 , where the control suitable for the idle charge is performed (detailed operation will be later explained). The amount of idle charge is calculated in the idle charge mode in step S 217 , then the operation proceeds to step S 218 . In step S 218 , a torque limit setting operation is performed. In this torque limit setting operation, the upper limit of the torque imposed on the engine is determined so as not to make the engine stall due to the idle charge.
If the result of the determination in step S 202 is “NO”, that is, if it is determined that the vehicle is not driving in a traffic jam, then the operation proceeds to step S 203 , where it is determined whether the value of the flag F_AT is 1. If the result of the determination is “NO”, that is, if it is determined that the vehicle employs an MT, then the operation jumps to step S 208 . If the result of the determination in step S 203 is “YES”, that is, if it is determined that the vehicle employs a CVT, then the operation proceeds to step S 204 . In step S 204 , it is determined whether the value of the flag F_ATNP (for determining the in-gear state of CVT) is 1.
If the result of the determination in step S 204 is “YES”, that is, if it is determined that the CVT is in the N or P range, then the operation jumps to step S 208 . If the result of the determination in step S 204 is “NO”, that is, if it is determined that the CVT is in the in-gear state, then in the next step S 205 , it is determined whether the previous value of the above flag F_ATNP, that is, the flag value in the last (operation) turn of this flow is 1. If the result of the determination is “YES”, that is, if it was determined in the last turn that the CVT was in the N or P range, then the operation jumps to step S 214 .
In step S 214 , the timer value of a non-idle mode selecting timer TIDLOUT for maintaining the non-idle state for a predetermined time is set to a predetermined value #TMIDLOUT. The operation then proceeds to step S 215 , where the final idle charge command value IDLRGNF is set to 0. In the next step S 216 , the mode is shifted to another mode (other than the idle mode), and in step S 219 , the final charge command value REGENF is set to the final idle charge command value IDLRGNF, and in the following step S 220 , the final assist command value ASTPWRF is set to 0. The control operation of this flow is then completed.
If the result of the determination in step S 205 is “NO”, that is, if it was determined in the last turn that the CVT was in the in-gear state (in the last turn), then in the next step S 206 , it is determined whether the value of the flag F_BKSW is 1. If the result of the determination is “YES”, that is, if it is determined that the brake is being depressed, then the operation proceeds to step S 208 . If the result of the determination in step S 206 is “NO”, that is, if it is determined that the brake is not currently being depressed, then the operation proceeds to step S 207 .
In step S 207 , it is determined whether the previous value of flag F_BKSW (i.e., the flag value in the last turn) is 1. If the result of the determination in step S 207 is “YES”, that is, if it was also determined that the brake was being depressed, then the operation jumps to step S 214 . If the result of the determination in step S 207 is “NO”, that is, if it was determined in the last turn that the brake was not being depressed, then the operation proceeds to step S 208 .
In step S 208 , it is determined whether the value of the above-explained flag F_THIDLMG is 1. If the result of the determination is “NO”, that is, if it is determined that the throttle is completely closed, then the operation proceeds to step S 209 . If the result of the determination in step S 208 is “YES”, that is, if it is determined that the throttle is not completely closed, then the operation proceeds to step S 210 . In step S 209 , it is determined whether the previous value of the flag F_THIDLMG in the last turn is 1. If the result of the determination is “NO”, that is, if it was determined in the last turn that the throttle was completely closed, the operation proceeds to step S 211 . If the result of the determination in step S 209 is “YES”, that is, if it was determined in the last turn that the throttle was not completely closed, then the operation jumps to step S 214 .
Also in step S 210 , it is determined whether the previous value of the flag F_THIDLMG in the last turn is 1. If the result of the determination is “NO”, that is, if it was determined in the last turn that the throttle was completely closed, the operation proceeds to step S 214 . If the result of the determination in step S 210 is “YES”, that is, if it was determined in the last turn that the throttle was not completely closed, then the operation jumps to step S 213 . In step S 211 , it is determined whether the previous value of flag F_DECFC is 1. This flag F_DECFC is provided for determining whether the fuel cut-off is being executed during deceleration. If the result of the determination is “YES”, that is, if the flag value is 1, then in the next step S 212 , it is determined whether the current value of the flag F_DECFC is 1. If the result of the determination in step S 211 is “NO”, that is, if the flag value is 0, then the operation proceeds to step S 213 .
If the result of the determination in step S 212 is “YES”, that is, if the relevant flag value is 1, then the operation proceeds to step S 213 . If the result of the determination in step S 212 is “NO”, that is, if the relevant flag value is 0, then the operation proceeds to step S 214 .
In step S 213 , it is determined whether the non-idle mode selecting timer TIDLOUT is 0. If the result of the determination is “YES”, the operation proceeds to step S 217 . If the result of the determination in step S 213 is “NO”, then the operation proceeds to step S 215 .
Accordingly, If the value of flag F_JAMST is 1, the battery 3 can be immediately and reliably charged in the idle charge mode without performing other determination processes included in the idle mode.
Idle Charge Mode
Below, the control of the idle charge mode will be explained with reference to the flowchart in FIG. 8 .
First, in step S 300 , it is determined whether the current SOC (i.e., remaining battery charge) QBAT is larger than a target value #QBNOBJ. This target value #QBNOBJ is predetermined in consideration of hysteresis. If the result of the determination is “YES”, that is, if the current SOC QBAT is large, then the operation proceeds to step S 305 , where an amount IDLRGN of the idle charge is set to 0. The operation then proceeds to step S 309 .
If the result of the determination in step S 300 is “NO”, that is, if the current SOC QBAT is low, then the operation proceeds to step S 330 , where it is determined whether the value of flag F_JAMST is 1. If the result of the determination in step S 330 is “YES”, that is, if it is determined that the vehicle is driving in a traffic jam, then the operation jumps to step S 308 (explained later).
If the result of the determination in step S 330 is “NO”, then the operation proceeds to step S 301 , where it is determined whether the value of the flag F_AT is 1. If the result of the determination is “NO”, that is, if it is determined that the vehicle employs an MT, then the operation jumps to step S 303 .
If the result of the determination in step S 301 is “YES”, that is, if it is determined that the vehicle employs a CVT, then the operation proceeds to step S 302 . In step S 302 , it is determined whether the value of the flag F_ATNP (for determining the in-gear state of CVT) is 1. If the result of the determination in step S 302 is “YES”, that is, if it is determined that the CVT is in the N or P range, then the operation proceeds to step S 303 .
If the result of the determination in step S 302 is “NO”, that is, if the CVT is in the in-gear state, then in the next step S 304 , it is determined whether the value of flag F_ACC is 1. This flag F_ACC is provided for determining whether the air conditioner clutch (switch) is on. If the result of the determination is “NO”, that is, if the air conditioner clutch is off, then the operation proceeds to step S 307 .
If the result of the determination in step S 304 is “YES”, that is, if the air conditioner clutch is on, then the operation proceeds to step S 306 , where the amount DLRGN of the idle charge is set to a low-mode value #IDLRGNL of the idle charge (i.e., set to a low charge level). The operation then proceeds to step S 309 .
In step S 303 , it is determined whether the value of the flag F_ACC is 1. If the result of the determination is “YES”, that is, if the air conditioner clutch is on, then the operation proceeds to step S 307 , where the amount IDLRGN of the idle charge is set to a middle-mode value #IDLRGNM of the idle charge (i.e., set to a middle charge level). The operation then proceeds to step S 309 .
If the result of the determination in step S 303 is “NO”, that is, if the air conditioner clutch is off, then the operation proceeds to step S 308 , where the amount IDLRGN of the idle charge is set to a high-mode value #IDLRGNH of the idle charge (i.e., set to a high charge level). The operation then proceeds to step S 309 . Also when the result of the above step S 330 is “YES”, then the amount IDLRGN of the idle charge is set to the high-mode value #IDLRGNH of the idle charge (i.e., set to a high charge level).
In step S 309 , a very small amount DIDLRGN of the idle charge is set to a predetermined small value #DIDLRGNO of the idle charge, then the operation proceeds to step S 310 . In step S 310 , it is determined whether an idle charge timer value TIDLRGN is 0. If the result of the determination is “NO”, that is, if the idle charge timer value TIDLRGN is not 0, the operation of this flow is completed.
If the result of the determination in step S 310 is “YES, that is, if the idle charge timer value TIDLRGN is 0, then the operation proceeds to step S 311 , where the idle charge timer value TIDLRGN is set to a predetermined small delay-timer value #TMIDLRGN of the idle charge, then the operation proceeds to step S 312 . In step S 312 , it is determined whether the above-explained final idle charge command value IDLRGNF is larger than the amount IDLRGN of the idle charge. If the result of the determination is “YES”, that is, if the final idle charge command value IDLRGNF is larger than the amount IDLRGN of the idle charge, then the operation proceeds to step S 315 .
If the result of the determination in step S 312 is “NO”, that is, if the final idle charge command value IDLRGNF is equal to or below the amount IDLRGN of the idle charge, then the operation proceeds to step S 313 , where the value of the very small amount DIDLRGN of the idle charge is added to the final idle charge command value IDLRGNF, then the operation proceeds to step S 314 .
In step S 314 , it is determined whether the final idle charge command value IDLRGNF is larger than the amount IDLRGN of the idle charge. If the result of the determination is “YES”, that is, if the final idle charge command value IDLRGNF is larger than the amount IDLRGN of the idle charge, then the operation proceeds to step S 317 .
If the result of the determination in step S 314 is “NO”, that is, if the final idle charge command value IDLRGNF is equal to or below the amount IDLRGN of the idle charge, then the operation of this flow is completed.
In step S 315 , the value of the very small amount DIDLRGN of the idle charge is subtracted from the final idle charge command value IDLRGNF, then the operation proceeds to step S 316 . In the step S 316 , it is determined whether the final idle charge command value IDLRGNF is below the amount IDLRGN of the idle charge. If the result of the determination is “NO”, that is, if the final idle charge command value IDLRGNF is equal to or above the amount IDLRGN of the idle charge, then this idle charge operation of this flow is completed.
If the result of the determination in step S 316 is “YES”, then the operation proceeds to step S 317 , where the final idle charge command value IDLRGNF is set to the value of the amount IDLRGN of the idle charge, then the idle charge operation of this flow is completed.
According to the above embodiment, when the remaining battery charge is below #QBJAM, if the maximum vehicle speed DRVMAX (during a single driving operation from start to stop) is below #VJAM, and if the degree of throttle opening is equal to or below #THJAM, then it is estimated that the energy charged in battery 3 has been reduced while the vehicle was driving in a traffic jam. Therefore, in order to charge battery 3 , the operation of the idle charge mode, which is a sub routine in the operation of the idle mode, is executed.
On the other hand, when the remaining battery charge is equal to or below #QBJAMST, if the maximum vehicle speed DRVMAX is below #VJAM, then it is estimated that the energy charged in battery 3 has been reduced while the vehicle was driving in a traffic jam. Therefore, in order to charge battery 3 , the operation of the idle charge mode, which is a sub routine in the operation of the idle mode, is executed regardless of the degree of throttle opening.
In addition, if the remaining battery charge of the battery device is below a predetermined value, and if it is determined that the vehicle is driving in a traffic jam, the motor assisting operation for assisting the engine output may be restricted (i.e., a lower assist level) by setting a higher threshold value which is provided for determining whether the assisting operation is started.
An embodiment of the present invention has been explained with reference to the drawings, but the present invention is not limited to the embodiment, and any design modification or variation is possible within the scope and spirit of the present invention. | A control system and method applied to a hybrid vehicle by which an excessive decrease of the remaining battery charge can be prevented while driving in a traffic jam. In the method, the remaining battery charge of the battery device is detected; and whether the vehicle is driving in a traffic jam is determined; and the charging device is made to charge the battery device if the detected remaining battery charge of the battery device is below a first predetermined value, and if it is determined that the vehicle is driving in a traffic jam. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. provisional patent application Ser. No. 61/143,152, filed Jan. 7, 2009, which is herein incorporated by reference.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] Embodiments of the present invention generally relate to a damper assembly for a vehicle. More specifically, the invention relates to a remotely operated bypass device used in conjunction with a vehicle damper.
[0003] Vehicle suspension systems typically include a spring component or components and a dampening component or components. Typically, mechanical springs, like helical springs are used with some type of viscous fluid-based dampening mechanism and the two are mounted functionally in parallel.
SUMMARY OF THE INVENTION
[0004] The present invention generally comprises a damper assembly having a bypass. In one aspect, the assembly comprises a cylinder with a piston and piston rod for limiting the flow rate of damping fluid as it passes from a first to a second portion of said cylinder. A bypass provides fluid pathway between the first and second portions of the cylinder and may be independent of, or in conjunction with, the aforementioned flow rate limitation. In one aspect, the bypass is remotely controllable from a passenger compartment of the vehicle. In another aspect, the bypass is remotely controllable based upon one or more variable parameters associated with the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] So that the manner in which the above recited features can be understood in detail, a more particular description may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
[0006] FIG. 1 is a section view showing a suspension damping unit with a remotely operable bypass, the bypass in a closed position.
[0007] FIG. 2 is a section view showing the suspension damping unit of FIG. 1 with the bypass in an open position.
[0008] FIG. 3 is a schematic diagram showing a control arrangement for a remotely operated bypass.
[0009] FIG. 4 is a schematic diagram showing another control arrangement for a remotely operated bypass.
[0010] FIG. 5 is a graph showing possible operational characteristics of the arrangement of FIG. 4 .
DETAILED DESCRIPTION
[0011] As used herein, the terms “down” “up” “downward” upward” “lower” “upper” and other directional references are relative and are used for reference only. FIGS. 1 and 2 are section views of a suspension damping unit 100 . The damper includes a cylinder portion 102 with a rod 107 and a piston 105 . Typically, the fluid meters, from one side to the other side of piston 105 , by passing through flow paths 110 , 112 formed in the piston 105 . In the embodiment shown, shims 115 , 116 are used to partially obstruct the flow paths 110 , 112 in each direction. By selecting shims 115 , 116 having certain desired stiffness characteristics, the dampening effects can be increased or decreased and dampening rates can be different between the compression and rebound strokes of the piston 105 . For example, shims 115 are configured to meter rebound flow from the rebound portion 103 of the cylinder 102 to the compression portion 104 of the cylinder 102 . Shims 116 , on the other hand, are configured to meter compression flow from the compression portion of the cylinder to the rebound portion. In one embodiment, shims 116 are not included on the rebound portion side leaving the piston essentially “locked out” in the compression stroke without some means of flow bypass. Note that piston apertures (not shown) may be included in planes other than those shown (e.g. other than apertures used by paths 110 and 112 ) and further that such apertures may, or may not, be subject to the shims 115 , 116 as shown (because for example, the shims 115 , 116 may be clover-shaped or have some other non-circular shape).
[0012] A reservoir 125 is in fluid communication with the damper cylinder 102 for receiving and supplying damping fluid as the piston rod 107 moves in and out of the cylinder. The reservoir includes a cylinder portion 128 in fluid communication with the damper cylinder 102 . The reservoir also includes a floating piston 130 with a volume of gas on a backside (“blind end” side) of it, the gas being compressible as the reservoir cylinder 128 fills with fluid due to movement of the damper rod 107 and piston 105 into the damper cylinder 102 . Certain features of reservoir type dampers are shown and described in U.S. Pat. No. 7,374,028, which is incorporated herein, in its entirety, by reference. The upper portion of the rod 107 is supplied with a bushing set 109 for connecting to a portion of a vehicle wheel suspension linkage. In another embodiment, not shown, the upper portion of the rod 107 (opposite the piston) may be supplied with an eyelet to be mounted to one part of the vehicle, while the lower part of the housing shown with an eyelet 108 is attached to another portion of the vehicle, such as the frame, that moves independently of the first part. A spring member (not shown) is usually mounted to act between the same portions of the vehicle as the damper. As the rod 107 and piston 105 move into cylinder 102 (during compression), the damping fluid slows the movement of the two portions of the vehicle relative to each other due to the incompressible fluid moving through the shimmed paths 110 , 112 (past shims 116 ) provided in the piston 105 and/or through the metered bypass 150 , as will be described herein. As the rod 107 and piston 105 move out of the cylinder 102 (during extension or “rebound”) fluid meters again through shimmed paths 110 and 112 and the flow rate and corresponding rebound rate is controlled by the shims 115 .
[0013] In one embodiment as shown in the Figures, a bypass assembly 150 is designed to permit damping fluid to travel from a first side of the piston to the other side without traversing shimmed flow paths 110 , 112 that may otherwise be traversed in a compression stroke of the damper. In FIG. 1 , the bypass 150 is shown in a closed position (e.g. a valve 170 obstructs fluid passage through entry way 160 ) and in FIG. 2 the bypass is shown in an open position (e.g. valve 170 is open and fluid may flow through passage 160 ). In FIG. 2 , the piston is shown moving downward in a compression stroke, the movement shown by arrow 157 . The bypass includes a cylindrical body 155 that communicates with the damper cylinder 102 through entry 160 and exit 165 pathways. In FIG. 2 , with the bypass open, the flow of fluid through the bypass is shown by arrow 156 . In one embodiment an entry valve 170 is located at the entry pathway 160 with a valve member 175 sealingly disposed and axially movable within the valve body. A needle-type check valve 180 , allowing flow in direction 156 and checking flow in the opposite direction, is located proximate exit pathway 165 . The needle valve sets flow resistance through the bypass 150 during compression and restricts fluid from entering the bypass cylinder 150 during a rebound stroke of the damper piston 105 . In one embodiment the needle valve 180 is spring loaded and biased closed. The initial compression force of the biasing spring 182 is adjusted via adjuster 183 thereby allowing a user to preset the needle valve opening pressure and hence the compression damping fluid flow rate (hence damping rate) through the bypass. The biasing force of the needle valve spring 182 is overcome by fluid pressure in the cylinder 155 causing the needle valve 180 to open during a compression stroke.
[0014] The entry pathway 160 and entry valve 170 in the embodiments shown in FIGS. 1 and 2 , are located towards a lower end of the damper cylinder 102 . In one embodiment, as selected by design, the bypass will not operate after the piston 105 passes the entry pathway 160 near the end of a compression stroke. This “position sensitive” feature ensures increased dampening will be in effect near the end of the compression stoke to help prevent the piston from approaching a “bottomed out” position (e.g. impact) in the cylinder 102 . In some instances, multiple bypasses are used with a single damper and the entry pathways for each may be staggered axially along the length of the damper cylinder in order to provide an ever-increasing amount of dampening (and less bypass) as the piston moves through its compression stroke and towards the bottom of the damping cylinder. Certain bypass damper features are described and shown in U.S. Pat. Nos. 6,296,092 and 6,415,895, each of which are incorporated herein, in its entirety, by reference.
[0015] In one embodiment the bypass 150 , as shown in FIGS. 1 and 2 , includes a fluid (e.g. hydraulic or pneumatic) fitting 201 disposed at an end of the entry valve body 170 . The fluid fitting 201 is intended to carry a control signal in the form of fluid pressure to the valve member 175 in order to move the valve 170 from an open to a closed position. In one embodiment, valve member 175 is biased open by an annular spring 171 located between an upper end of the valve member 175 and the lower axial end face of tube 155 .
[0016] In one example, the valve 170 is moved to a closed position and the bypass feature disabled by remote control from a simple operator-actuated switch located in the passenger compartment of the vehicle. In one embodiment, fluid pressure for controlling (e.g. closing) the valve 170 is provided by the vehicle's own source of pressurized hydraulic fluid created by, for example, the vehicle power steering system. In one embodiment, pneumatic pressure is used to control (e,g, close) the valve 170 where the pneumatic pressure is generated by an on-board compressor and accumulator system and conducted to the valve 170 via a fluid conduit. In one embodiment, a linear electric motor (e.g. solenoid), or other suitable electric actuator, is used to move valve member 175 axially within valve body. A shaft of the electric actuator (not shown) may be fixed to the valve member 175 such that axial movement of the shaft causes axial movement of the valve member 175 . In one embodiment, the electric actuator is configured to “push” the valve member 175 to a closed position and to “pull” the valve member 175 to an open position depending on the direction of the current switched through the actuator. In one embodiment, the valve 170 is spring biased, for example, to an open position as previously described herein, and the actuator, being switched by a potentiometer or other suitable current or voltage modulator, moves the valve member 175 against the biasing spring to a closed position or to some position of desired partial closure (depending on the operation of the switch). Such partial closure increases the compression stiffness of the damper but does not provide the more rigid dampening of complete bypass closure. In such electrical embodiments, the solenoid is wired (e.g. via electrical conduit) into the vehicle electrical system and switched to move the valve 170 as described herein.
[0017] FIG. 3 is a schematic diagram illustrating a sample circuit 400 used to provide remote control of a bypass valve using a vehicle's power steering fluid (although any suitable fluid pressure source may be substituted for reservoir 410 as could an electrical current source in the case of an electrically actuated valve member 175 ). As illustrated, a fluid pathway 405 having a switch-operated valve 402 therein runs from a fluid (or current) reservoir 410 that is kept pressurized by, in one embodiment, a power steering pump (not shown) to a bypass valve 170 that is operable, for example, by a user selectable dash board switch 415 . The valve 402 permits fluid to travel to the bypass valve 170 , thereby urging it to a closed position. When the switch 415 is in the “off” position, working pressure within the damper, and/or a biasing member such as a spring 171 (as described herein in relation to FIGS. 1 & 2 ) or annular atmospheric chamber (not shown), returns the bypass to its normally-open position. Hydraulically actuated valving for use with additional components is shown and described in U.S. Pat. No. 6,073,536 and that patent is incorporated by reference herein in its entirety. While FIG. 3 is simplified and involves control of a single bypass valve, it will be understood that the valve 402 could be plumbed to simultaneously provide a signal to two or more bypass valves operable with two or more vehicle dampers and/or with a single damper having multiple bypass channels and multiple corresponding valves (e.g. 175 ). Additional switches could permit individual operation of separate damper bypass valves in individual bypass channels, whether on separate dampers or on the same multiple bypass damper, depending upon an operator's needs. While the example of FIG. 3 uses fluid power for operating the bypass valve, a variety of means are available for remotely controlling a valve. For instance, a source of electrical power from a 12 volt battery could be used to operate a solenoid member, thereby shifting valve member 175 in bypass valve 170 between open and closed positions. The signal can be either via a physical conductor or an RF signal (or other wireless such as Bluetooth, WiFi, ANT) from a transmitter operated by the switch 415 to a receiver operable on the bypass valve 175 .
[0018] A remotely operable bypass like the one described above is particularly useful with an on/off road vehicle. These vehicles can have as much as 20″ of shock absorber travel to permit them to negotiate rough, uneven terrain at speed with usable shock absorbing function. In off-road applications, compliant dampening is necessary as the vehicle relies on its long travel suspension when encountering off-road obstacles. Operating a vehicle with very compliant, long travel suspension on a smooth road at higher speeds can be problematic due to the springiness/sponginess of the suspension. Such compliance can cause reduced handling characteristics and even loss of control. Such control issues can be pronounced when cornering at high speed as a compliant, long travel vehicle may tend to roll excessively. Similarly, such a vehicle may pitch and yaw excessively during braking and acceleration. With the remotely operated bypass “lock out” described herein, dampening characteristics of a shock absorber can be completely changed from a compliantly dampened “springy” arrangement to a highly dampened and “stiffer” system ideal for higher speeds on a smooth road. In one embodiment where compression flow through the piston is completely blocked, closure of the bypass 150 results in substantial “lock out” of the suspension (the suspension is rendered essentially rigid). In one embodiment where some compression flow is allowed through the piston (e.g. ports 110 , 112 and shims 116 ), closure of the bypass 150 results in a stiffer but still functional compression damper. In one embodiment, the needle valve 180 is tuned (using adjuster 183 ), and the shims 116 sized, to optimize damping when the bypass 150 is open and when bypass 150 is closed based on total anticipated driving conditions. In one embodiment the needle valve adjuster 183 is connected to a rotary electrical actuator so that adjustment of the needle valve4 180 may be performed remotely as disclosed herein referencing the bypass valve 170 .
[0019] In addition to, or in lieu of, the simple, switch operated remote arrangement of FIG. 3 , the remote bypass can be operated automatically based upon one or more driving conditions. FIG. 4 shows a schematic diagram of a remote control system 500 based upon any or all of vehicle speed, damper rod speed, and damper rod position. One embodiment of FIG. 4 is designed to automatically increase dampening in a shock absorber in the event a damper rod reaches a certain velocity in its travel towards the bottom end of a damper at a predetermined speed of the vehicle. In one embodiment the system adds dampening (and control) in the event of rapid operation (e.g. high rod velocity) of the damper to avoid a bottoming out of the damper rod as well as a loss of control that can accompany rapid compression of a shock absorber with a relative long amount of travel. In one embodiment the system adds dampening (e.g. closes or throttles down the bypass) in the event that the rod velocity in compression is relatively low, but the rod progresses past a certain point in the travel. Such configuration aids in stabilizing the vehicle against excessive low rate suspension movement events such as cornering roll, braking and acceleration yaw and pitch and “g-out.”
[0020] FIG. 4 illustrates, for example, a system including three variables: rod speed, rod position and vehicle speed. Any or all of the variables shown may be considered by processor 502 in controlling the valve 175 . Any other suitable vehicle operation variable may be used in addition to or in lieu of the variables 515 , 505 , 510 such as for example piton rod compression strain, eyelet strain, vehicle mounted accelerometer data or any other suitable vehicle or component performance data. In one embodiment, a suitable proximity sensor or linear coil transducer or other electro-magnetic transducer is incorporated in the dampening cylinder to provide a sensor to monitor the position and/or speed of the piston (and suitable magnetic tag) with respect to the cylinder. In one embodiment, the magnetic transducer includes a waveguide and a magnet, such as a doughnut (toroidal) magnet that is joined to the cylinder and oriented such that the magnetic field generated by the magnet passes through the piston rod and the waveguide. Electric pulses are applied to the waveguide from a pulse generator that provides a stream of electric pulses, each of which is also provided to a signal processing circuit for timing purposes. When the electric pulse is applied to the waveguide a magnetic field is formed surrounding the waveguide. Interaction of this field with the magnetic field from the magnet causes a torsional strain wave pulse to be launched in the waveguide in both directions away from the magnet. A coil assembly and sensing tape is joined to the waveguide. The strain wave causes a dynamic effect in the permeability of the sensing tape which is biased with a permanent magnetic field by the magnet. The dynamic effect in the magnetic field of the coil assembly due to the strain wave pulse, results in an output signal from the coil assembly that is provided to the signal processing circuit along signal lines. By comparing the time of application of a particular electric pulse and a time of return of a sonic torsional strain wave pulse back along the waveguide, the signal processing circuit can calculate a distance of the magnet from the coil assembly or the relative velocity between the waveguide and the magnet. The signal processing circuit provides an output signal, either digital or analog, proportional to the calculated distance and/or velocity. Such a transducer-operated arrangement for measuring rod speed and velocity is described in U.S. Pat. No. 5,952,823 and that patent is incorporated by reference herein in its entirety.
[0021] While a transducer assembly located at the damper measures rod speed and location, a separate wheel speed transducer for sensing the rotational speed of a wheel about an axle includes housing fixed to the axle and containing therein, for example, two permanent magnets. In one embodiment the magnets are arranged such that an elongated pole piece commonly abuts first surfaces of each of the magnets, such surfaces being of like polarity. Two inductive coils having flux-conductive cores axially passing therethrough abut each of the magnets on second surfaces thereof, the second surfaces of the magnets again being of like polarity with respect to each other and of opposite polarity with respect to the first surfaces. Wheel speed transducers are described in U.S. Pat. No. 3,986,118 which is incorporated herein by reference in its entirety.
[0022] In one embodiment, as illustrated in FIG. 4 , a logic unit 502 with user-definable settings receives inputs from the rod speed 510 and location 505 transducers as well as the wheel speed transducer 515 . The logic unit is user-programmable and depending on the needs of the operator, the unit records the variables and then if certain criteria are met, the logic circuit sends its own signal to the bypass to either close or open (or optionally throttle) the bypass valve 175 . Thereafter, the condition of the bypass valve is relayed back to the logic unit 502 .
[0023] FIG. 5 is a graph that illustrates a possible operation of one embodiment of the bypass assembly 500 of FIG. 4 . The graph assumes a constant vehicle speed. For a given vehicle speed, rod position is shown on a y axis and rod velocity is shown on an x axis. The graph illustrates the possible on/off conditions of the bypass at combinations of relative rod position and relative rod velocity. For example, it may be desired that the bypass is operable (bypass “on”) unless the rod is near its compressed position and/or the rod velocity is relatively high (such as is exemplified in FIG. 5 ). The on/off configurations of FIG. 5 are by way of example only and any other suitable on/off logic based on the variable shown or other suitable variables may be used. In one embodiment it is desirable that the damper become relatively stiff at relatively low rod velocities and low rod compressive strain (corresponding for example to vehicle roll, pitch or yaw) but remains compliant in other positions. In one embodiment the piston rod 107 includes a “blow off” (overpressure relief valve typically allowing overpressure flow from the compression side to the rebound side) valve positioned in a channel coaxially disposed though the rod 107 and communicating one side of the piston (and cylinder) with the other side of the piston (and cylinder) independently of the apertures 110 , 112 and the bypass 150 .
[0024] In one embodiment, the logic shown in FIG. 4 assumes a single damper but the logic circuit is usable with any number of dampers or groups of dampers. For instance, the dampers on one side of the vehicle can be acted upon while the vehicles other dampers remain unaffected.
[0025] While the examples illustrated relate to manual operation and automated operation based upon specific parameters, the remotely operated bypass can be used in a variety of ways with many different driving and road variables. In one example, the bypass is controlled based upon vehicle speed in conjunction with the angular location of the vehicle's steering wheel. In this manner, by sensing the steering wheel turn severity (angle of rotation), additional dampening can be applied to one damper or one set of dampers on one side of the vehicle (suitable for example to mitigate cornering roll) in the event of a sharp turn at a relatively high speed. In another example, a transducer, such as an accelerometer measures other aspects of the vehicle's suspension system, like axle force and/or moments applied to various parts of the vehicle, like steering tie rods, and directs change to the bypass valve positioning in response thereto. In another example, the bypass can be controlled at least in part by a pressure transducer measuring pressure in a vehicle tire and adding dampening characteristics to some or all of the wheels in the event of, for example, an increased or decreased pressure reading. In still another example, a parameter might include a gyroscopic mechanism that monitors vehicle trajectory and identifies a “spin-out” or other loss of control condition and adds and/or reduces dampening to some or all of the vehicle's dampers in the event of a loss of control to help the operator of the vehicle to regain control.
[0026] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | A damper assembly with a bypass for a vehicle comprises a pressure cylinder with a piston and piston rod for limiting the flow rate of damping fluid as it passes from a first to a second side of said piston. A bypass provides fluid pathway between the first and second sides of the piston separately from the flow rate limitation. In one aspect, the bypass is remotely controllable from a passenger compartment of the vehicle. In another aspect, the bypass is remotely controllable based upon one or more variable parameters associated with the vehicle. | 5 |
BACKGROUND
[0001] The present invention relates to a mold core for molding and controlling the temperature of a hollow structure and to a method for producing such a mold core.
[0002] Mold cores are normally used to produce hollow structures, for example fiber composite structures. A distinction can be made between single-use cores and repeat-use cores, whereby repeat-use cores can be reused while single-use cores are washed out of the finished hollow structure and thereby destroyed after a single use. This can be meaningful if due to the geometry of the hollow structure to be produced there is no possibility of the usual removal of the mold core. Single-use cores can be removed, i.e. rinsed out, chemically, thermally or by means of a liquid and usually consist of a mold core base material and a binding agent.
[0003] German document DE 195 34 836 C2 discloses a water-soluble mold core for injection molding of plastic parts. Enrichment of the mold core material with metal powder particles and other materials is provided in order to improve the processability of the mold core material. Also disclosed is the coating of the mold core with a covering layer which is maximum 0.3 mm thick and has, inter alia, graphite as a constituent part. A further layer is intended to improve the surface quality of the mold core. Thus the, disclosed mold core has the disadvantage, however, that it has no means for heating the hollow structure to be molded. The hardening of the hollow structure thus takes place relatively slowly and lacks any means for guaranteeing even hardening.
[0004] European document EP 1 323 686 B1 discloses a method for producing mold cores which in turn are to be used to form hollow bodies comprising fiber reinforced ceramic materials. Through electrical resistance heating the mold core can be heated. In this connection additional electrically conducting substances are homogeneously mixed with the starting material of the mold core. By means of such mold cores in particular local overheating is to be avoided. However, in practice this is not possible to a sufficient extent.
SUMMARY
[0005] It is thus the object of the present invention to provide a mold core which can be heated so even temperature distribution occurs or a temperature distribution which can be specifically defined as desired results on its outer surface.
[0006] According to the invention this object is achieved by a mold core for molding and controlling the temperature of a hollow structure wherein the mold core comprises an electrically non-conducting or only slightly conducting inner area and an electrically conducting outer area as well as two electrical contacts accessible from outside for applying a voltage, wherein the thickness of the outer area is constant or is specifically varied.
[0007] In some contemplated embodiments of the invention, the outer area of the mold core can consist of a mold core base material that is enriched with electrically conducting material, such as for example conducting carbon black, graphite, short and/or long carbon fibers and/or metal powder or fibers, wherein the proportion of the electrically conducting material is constant or is specifically varied.
[0008] In some a further contemplated embodiments of the invention, a contact surface between the inner area and the outer area is formed to be smooth. “Smooth” is intended here to be interpreted as limited roughness of the contact surface.
[0009] Alternatively, in some contemplated embodiments a contact surface can be produced in the form of fins between the inner area and the outer area. In some particular contemplated embodiments of the invention, a contact surface between the inner area and the outer area is coated with silver varnish. According to further contemplated embodiments of the invention, a mold core is formed as a single-use core and can for example be rinsed out using a liquid.
[0010] The invention further relates to a method for producing a mold core, comprising molding a first body to form an inner electrically non-conducting or only slightly conducting area of the mold core, and applying molding material to the first body to form an outer electrically conducting area of the mold core and attaching two electrical contacts accessible from outside for applying a voltage, wherein the thickness of the outer area is constant or is specifically varied. The thickness can be constant in spatial or area-based terms or can be specifically varied.
[0011] A further aspect of the invention relates to the use of a mold core as described above to mold and control the temperature of a hollow structure, comprising: incorporating a material provided to produce the hollow structure into a mold, incorporating the mold core into the mold, closing the mold and producing an electrical connection for applying a voltage to the two electrical contacts of the mold core to heat the material, and after hardening of the material is complete for the hollow structure, removing the electrical connection and removing the mold core preferably through rinsing out of the hollow structure and the mold. Alternatively the mold core can also only be removed from the hollow structure once this has already been removed from the mold.
[0012] The invention is based upon the surprising recognition that through a multi-layer structure of a mold core due to the formation of an inner and an outer area and an interplay between the thickness of the outer area and the thickness of the inner area the heat production properties of a current flowing therethrough can be influenced and controlled such that at each point, and especially each point of the outer surface, of the mold core a certain quantity of heat can be achieved. The local temperature to be produced can be predefined more precisely than is possible with other known production methods or other known mold cores with comparably low resources. The mold core according to the invention also allows for the particularly efficient heating of a hollow structure as heat is produced directly on the surface of the core where it is required.
[0013] A particularly surprising effect of the invention is found in that the structure comprising two areas allows not only a control of heat distribution but also simultaneously offers thermal insulation of the inner area and thus avoids a heat sink inside the mold core. At the same time there is no unnecessary heating of areas of the mold core which are not in contact with the hollow structure, allowing for the further advantage of efficient energy use. This also offers, in comparison with the use of liquid or other movable heat carriers, the additional advantage that the mold core is particularly simple both in regard to its structure as well as in the steps necessary for its construction.
[0014] A further advantage of the current invention is that the inherit difficulties posed by movable heat carriers in connection with soluble single-use cores are avoided.
[0015] An advantage of the invention lies in that alternative heating methods which provide, for example, metal heating coils in the mold core can only be consistently reconciled with difficulty, and in particular with the dissolution of a single-use core.
[0016] In addition, the present invention allows local thermal expansions and stresses in the mold core to be avoided. As discussed in the above background discussion, it has not been previously possible to date to effectively counteract local thermal expansions, and resulting stresses therefore constitute an unresolved problem according to the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Further features and advantages of the invention follow from the claims and from the following description, in which example embodiments are explained using the schematic drawings in which:
[0018] FIG. 1 is a side view of a mold core according to one contemplated embodiment of the invention in a hollow structure in section; and
[0019] FIG. 2 is a side view of a mold core according to one contemplated embodiment of the invention.
DETAILED DESCRIPTION
[0020] The mold core 10 shown in FIG. 1 is in area contact with a hollow structure 11 or its starting material in a mold (not shown) which is to be molded and temperature-controlled by the mold core. The mold core 10 comprises an inner area 13 and an outer area 12 , wherein the outer area 12 covers the inner area 13 on all sides towards the hollow structure. The mold core 10 can be divided in the embodiment shown into sections of differing thickness of the mold core 10 , that is to say cylindrical sections with different radii. The mold core 10 is thus considerably thinner in the section 19 a than in the section 19 b.
[0021] The outer area 12 preferably consists of molding sand which is enriched with certain electrically conducting materials in order to increase its electrical conductivity. Such a material can, for example, be conducting carbon black or graphite. Alternatively, however, short or long carbon fibers can also be used as can metal powder and/or metal fibers. The inner area 13 preferably consists of molding sand and therefore either does not conduct the electric current or, if it does conduct electric current, then it does so only to a limited extent. The inner area 13 also preferably comprises merely a low heat conductivity. It can be seen in particular from FIG. 1 that the thickness in the radial direction of the outer area 12 can vary locally in relation to the thickness of the inner area 13 . Its thickness for example in the section 19 a is considerably greater than in the section 19 b. A greater thickness results in a lower electrical resistance which in turn leads to a lower heating effect of a current flowing through.
[0022] In some contemplated embodiments the mold core 10 can be formed as a hollow core, wherein the inner area 13 comprises at least in part a hollow chamber.
[0023] For the purpose of electrical resistance heating of the mold core, the outer area 12 is provided with contacts, to which a voltage can be applied. The contacts are not shown in FIG. 1 . However, they can be arranged at any points of the outer area 12 . For example the contacts can be arranged at opposing sides of the mold core. However, depending upon the requirements of the hollow structure to be hardened, a different constellation of the contacts is also conceivable.
[0024] In order to account for the different thermal conductivities of the inner area 13 and the outer area 12 , the contact surface between two areas can be formed to be smooth. A smooth surface is thereby understood to be a surface of limited roughness. Alternatively, the contact surface can be formed with fins or comprise a three-dimensional structure in another way. In particular in this way the contact surface between the inner area 13 and the outer area 12 can be enlarged. In one contemplated embodiment the surface can be enlarged by fin-like contacts, for example by factor 3.4 in comparison with a smooth contact surface. Alternatively, in some contemplated embodiments the contact surface can be provided with a silver varnish coating. This serves in particular as an extensive thermal insulation of the inner area 13 from the outer area 12 in order to be able to adjust the desired heat distribution more precisely.
[0025] The form of the mold core according to the invention can thus be realized as desired both in longitudinal and in transverse directions.
[0026] In one contemplated example embodiment described below, a hollow structure is produced which comprises a hollow space in the form of two coaxially arranged hollow cylinders with differing radii. Subject to the secondary condition that the mold core corresponding to the hollow space is to produce over its whole outer surface an even heat development, it is the intention to determine with given outer dimensions of the mold core the necessary cross-sectional area of the inner area on a certain section. The outer area 12 of the mold core in section 19 a may have an inner radius r inside,1 and an outer radius r outside,1 and in section 19 b an outer radius r outside,2 . The question is then posed as to how large the inner radius r inside,2 in section 19 b must be in order to provide the same heat output in an outward sense. In this connection consider:
[0027] The circumference of a cylinder is given as
[0000] U= 2 π·r
[0028] With increasing circumference U the heat output to be provided necessary to bring about constant temperature control increases linearly. This heat output is, in addition, proportional to the electrical resistance R. Furthermore the cross-sectional area of a cylindrical inner area 13 is proportional.
[0000] A inside =π·r 2 inside ,
[0029] The total cross-sectional area A of a cylinder i amounts to
[0000] A i =π·r 2 outside .
[0030] The cross-sectional area A outside,i of the outer area 12 without the inner area 13 for a cylinder i can thus be indicated as
[0000] A outside,i =A−A inside .
[0000] The electrical resistance of a cylinder i is inversely proportional to the cross-sectional area A outside,i of its outer area 12 . For two cylinders 1 and 2 this equation can be given as
[0000]
A
outside
,
1
A
outside
,
2
=
R
2
R
1
.
[0000] Furthermore the following applies:
[0000]
R
2
R
1
=
U
2
U
1
⇒
A
outside
,
2
=
U
1
U
2
·
A
outside
,
1
.
[0000] The desired radius r inside,2 can be calculated from this equation from
[0000]
A
outside
,
2
=
π
·
r
outside
,
2
2
-
π
·
r
inside
,
2
2
;
U
1
U
2
·
A
outside
,
1
=
2
π
·
r
outside
,
1
2
π
·
r
outside
,
2
·
(
π
·
r
outside
,
1
2
-
π
·
r
inside
,
1
2
)
⇒
r
inside
,
2
=
r
outside
,
2
2
-
r
outside
,
1
r
outside
,
2
·
(
r
outside
,
1
2
-
r
inside
,
1
2
)
[0031] Therefore, with a fixed radius r outside,1 on a first section 19 a of the mold core 10 and fixed radius r outside,2 on a second section 19 b of the mold core 10 the outer radius (=r inside,1 ) of the inner area 13 can be selected on the first section 19 a so that a predetermined heating is produced on the first section 19 a, and the outer radius (=r inside,2 ) of the inner area 13 on the second section 19 b is selected depending on r inside,1 , r outside,1 and r outside,2 such that the same heating is produced on the second section 19 b as on the first section 19 a. The cross-sectional area of the inner and outer area on the section 19 b is thus known.
[0032] According to a contemplated alternative embodiment with square, rectangular or any cross-sectional forms of the mold core, the above equations can be similarly used, wherein merely the correct functions are to be used to calculate the respective cross-sectional area and circumference.
[0033] FIG. 2 depicts a further contemplated embodiment of the invention wherein a mold core 20 is shown with an inner area 23 and an outer area 22 . The areas 22 and 23 have a cross-section in the longitudinal direction of the mold core 20 which continually changes over several sections, for example in the section marked A. Transversely to the longitudinal direction of the mold core the areas 22 and 23 have a rectangular cross-section. FIG. 2 further depicts a temperature profile 21 on the surface of the outer area 22 . This shows for example that in section A, a very much lower temperature prevails than in section B. This difference is due to the fact that the thickness of the outer area 22 in section B is very much smaller than in section A. The outer area 22 thereby has in section B a greater electrical resistance than in section A, whereby this leads, when an electric current flows therethrough, to a higher heating effect and thus to increased temperature. The temperature profile 21 further exhibits a slight increase of temperature in section A of the outer area 22 in the direction of section B. This results from the tapering thickness of the outer area 22 in section A in the direction of section B and is based upon an associated continuous reduction in the electrical resistance of the outer area 22 . The composition of the areas 22 and 23 of FIG. 2 and the remaining properties of the mold core 20 shown can, moreover, comprise the same properties as the mold core 10 of FIG. 1 .
[0034] The above approaches for influencing local heating within a mold core, which—as shown—are based in particular upon an adaptation of the area thicknesses, can be advantageously combined with an enrichment of additional materials in the outer area 12 that differs in spatial or area-related terms. In particular, a particularly great local variation of the area thicknesses according to the above provisions can be weakened in that, through the addition of electrically conducting additional materials in the area in question, the electric conduction properties are adapted so that only a lower variation in area thicknesses is necessary. When selecting such additional materials it is not only electrical conductivity but also heat conductivity that is also to be considered, whereby for example, in case of an increase in the electrical resistance, an improvement in the heat conductivity is to be sought. This requirement is fulfilled, for example, by conducting carbon black, graphite, or carbon fibers, whereby the latter can be present as short or long fibers. Alternatively or additionally metal powder and/or metal fibers can also be used. Finally, combinations of such materials can also be used. Graphite is noted as one such preferable material as it not only has a high heat conductivity and electrical conductivity but also a high temperature resistance as well as a high temperature change resistance. The latter favours an acceleration of heating and cooling phases during the hardening processes of a fiber composite structure. In addition, graphite has a high resistance to oxidation and is particularly resistant to certain chemicals. Graphite can also be produced with high purity levels and is easy to process, environmentally friendly, and is safe with regard to health during processing.
[0035] The invention can be used to produce hollow structures, for example fiber composite structures, in pressure casting methods, or in the field of injection molding processes. In general the invention constitutes an improvement in the production of complex hollow structures, in which it is necessary or advantageous to control temperature.
[0036] In order to produce a mold core according to the above-described embodiments, essentially two steps are necessary. First, the inner electrically non-conducting or only slightly conducting area is formed, wherein, for example, a pressure process is used. Typically the inner area thereby consists of molding sand. Second, the outer electrically conducting area 12 is applied to the inner area 13 so that the outer area 12 covers the inner area 13 . Furthermore, contacts are supplied on the outer area 12 in order to allow the application of a voltage to the outer area 12 . The thicknesses of the two areas are thereby measured to suit the respective requirements of the application, in particular in consideration of the above indications relating to the invention.
[0037] In order to use the mold core according to the invention to mold and control the temperature of a hollow structure 11 to be hardened, according to one contemplated embodiment, initially a substance provided to produce the hollow structure is incorporated into a mold. Subsequently the mold core is embedded in the mold so that it forms with it a cavity. Methods known to those skilled in the art can be used in this connection. Subsequently a voltage is applied to the two contacts of the mold core 12 in order to heat the substance. After complete hardening of the hollow structure 11 , the electrical connection is removed and the mold core 10 —if it is a single-use core—is rinsed out of the hollow structure and the mold or only after removal of the hollow structure from the mold, or—if the core is a reusable core—is removed from the hollow structure 11 and the mold in a different way to allow for later use.
[0038] In the embodiments shown and described above, a mold core is described which constitutes a new and particularly efficient way of achieving a certain distribution for hardening a surrounding fiber composite structure. Besides the aforementioned advantages of the invention, reference is made to a particularly simple, rapid and cost-effective core production which can additionally be advantageously automated. Due to the simple structure, low costs are to be expected in the construction of such a mold core, in particular as the main constituent parts of a corresponding installation merely comprise a power generator and a power control. The aforementioned environmental friendliness of the mold core according to the invention is further based on the fact that no medium for supplying heat to the core is necessary. There is thus no waste product, for which disposal could be expensive.
[0039] The features of the invention disclosed in the present description, in the drawings and in the claims can be used both individually and in any combinations for the realization of the invention in its different embodiments. This invention has been described with reference to several preferred embodiments. Many modifications and alterations will occur to others upon reading and understanding the preceding specifications. It is intended that the invention be construed as including all such alterations and modifications and so far as they come within the scope of the appended claims or the equivalence of these claims. | A mold core for molding and controlling the temperature of a hollow structure comprises an electrically non-conducting or only slightly conducting inner area and an electrically conducting outer area and two electrical contacts accessible from outside for applying a voltage, wherein the thickness of the outer area is constant or is specifically varied. A method for producing a mold core comprises molding a first body to form an inner electrically non-conducting or only slightly conducting area of the mold core and applying molding material to the first body to form an outer electrically conducting area of the mold core and attaching two electrical contacts accessible from outside for applying a voltage, wherein the thickness of the outer area is constant or specifically varied. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a divisional of, and claims benefit and priority of U.S. Non-Provisional patent Application Ser. No. 11/444,603, filed May 31, 2006, entitled “METHODS AND SYSTEMS FOR ANEURYSM TREATMENT USING FILLING STRUCTURES”, which claims benefit and priority of U.S. Provisional Patent Application No. 60/753,327, filed Dec. 22, 2005, entitled “METHODS AND SYSTEMS FOR ENDOVASCULAR ANEURYSM TREATMENT USING FILLING STRUCTURES;” the entire contents of each are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention. The present invention relates generally to medical apparatus and methods for treatment. More particularly, the present invention relates to methods and systems for crossing and filling abdominal and other aneurysms.
[0003] Aneurysms are enlargements or “bulges” in blood vessels which are often prone to rupture and which therefore present a serious risk to the patient. Aneurysms may occur in any blood vessel but are of particular concern when they occur in the cerebral vasculature or the patient's aorta.
[0004] The present invention is particularly concerned with aneurysms occurring in the aorta, particularly those referred to as aortic aneurysms. Abdominal aortic aneurysms (AAA's) are classified based on their location within the aorta as well as their shape and complexity. Aneurysms which are found below the renal arteries are referred to as infrarenal abdominal aortic aneurysms. Suprarenal abdominal aortic aneurysms occur above the renal arteries, while thoracic aortic aneurysms (TAA's) occur in the ascending, transverse, or descending part of the upper aorta.
[0005] Infrarenal aneurysms are the most common, representing about eighty percent (80%) of all aortic aneurysms. Suprarenal aneurysms are less common, representing about 20% of the aortic aneurysms. Thoracic aortic aneurysms are the least common and often the most difficult to treat. Most or all present endovascular systems are also too large (above 12 F) for percutaneous introduction.
[0006] The most common form of aneurysm is “fusiform,” where the enlargement extends about the entire aortic circumference. Less commonly, the aneurysms may be characterized by a bulge on one side of the blood vessel attached at a narrow neck. Thoracic aortic aneurysms are often dissecting aneurysms caused by hemorrhagic separation in the aortic wall, usually within the medial layer. The most common treatment for each of these types and forms of aneurysm is open surgical repair. Open surgical repair is quite successful in patients who are otherwise reasonably healthy and free from significant co-morbidities. Such open surgical procedures are problematic, however, since access to the abdominal and thoracic aortas is difficult to obtain and because the aorta must be clamped off, placing significant strain on the patient's heart.
[0007] Over the past decade, endoluminal grafts have come into widespread use for the treatment of aortic aneurysm in patients who cannot undergo open surgical procedures. In general, endoluminal repairs access the aneurysm “endoluminally” through either or both iliac arteries in the groin. The grafts, which typically have been fabric or membrane tubes supported and attached by various stent structures, are then implanted, typically requiring several pieces or modules to be assembled in situ. Successful endoluminal procedures have a much shorter recovery period than open surgical procedures.
[0008] Present endoluminal aortic aneurysm repairs, however, suffer from a number of limitations. A significant number of endoluminal repair patients experience leakage at the proximal juncture (attachment point closest to the heart) within two years of the initial repair procedure. While such leaks can often be fixed by further endoluminal procedures, the need to have such follow-up treatments significantly increases cost and is certainly undesirable for the patient. A less common but more serious problem has been graft migration. In instances where the graft migrates or slips from its intended position, open surgical repair is required. This is a particular problem since the patients receiving the endoluminal grafts are often those who are not considered good candidates for open surgery. Further shortcomings of the present endoluminal graft systems relate to both deployment and configuration. Current devices are unsuitable for treating many geometrically complex aneurysms, particularly infrarenal aneurysms with little space between the renal arteries and the upper end of the aneurysm, referred to as short-neck or no-neck aneurysms. Aneurysms having torturous geometries, are also difficult to treat.
[0009] For these reasons, it would be desirable to provide improved methods and systems for the endoluminal and minimally invasive treatment of aortic aneurysms. In particular, it would be desirable to provide systems and methods which provide prostheses with minimal or no endoleaks, which resist migration, which are relatively easy to deploy, and which can treat many if not all aneurysmal configurations, including short-neck and no-neck aneurysms as well as those with highly irregular and asymmetric geometries. It would be further desirable to provide systems and methods which are compatible with current designs for endoluminal stents and grafts, including single lumen stents and grafts, bifurcated stents and grafts, parallel stents and grafts, as well as with double-walled filling structures which are the subject of the commonly owned, copending applications described below. The systems and methods would preferably be deployable with the stents and grafts at the time the stents and grafts are initially placed. Additionally, it would be desirable to provide systems and methods for repairing previously implanted aortic stents and grafts, either endoluminally or percutaneously. At least some of these objectives will be met by the inventions described hereinbelow.
[0010] 2. Description of the Background Art. US2006/0025853 describes a double-walled filling structure for treating aortic and other aneurysms. Copending, commonly owned application Ser. No. 11/413,460, describes the use of liners and extenders to anchor and seal such double-walled filling structures within the aorta. The full disclosures of both these pending applications are incorporated herein by reference. WO 01/21108 describes expandable implants attached to a central graft for filling aortic aneurysms. See also U.S. Pat. Nos. 5,330,528; 5,534,024; 5,843,160; 6,168,592; 6,190,402; 6,312,462; 6,312,463; US2002/0045848; US2003/0014075; US2004/0204755; US2005/0004660; and WO 02/102282.
BRIEF SUMMARY OF THE INVENTION
[0011] The present invention provides methods and systems for the treatment of aneurysms, particularly aortic aneurysms including both abdominal aortic aneurysms (AAA's) and thoracic aortic aneurysms (TAA's). Treatments are particularly useful in endoluminal protocols where vascular catheters may be used to advance and manipulate the various system components. In some instances, however, the systems and methods will also be useful for the percutaneous, minimally invasive treatment of aneurysms where the aneurysm may be accessed from the outside through a controlled penetration in the aneurysmal wall.
[0012] Systems according to the present invention comprise a scaffold which is adapted to be placed across the aneurysm to provide one or more blood flow lumens thereacross. The scaffold may be any type of conventional aneurysmal treatment scaffold, including bare stents, grafts, stent-reinforced grafts, double-walled filling structures (as described in detail in copending application Ser. No. 11/413,460, the full disclosure of which has been previously incorporated herein by reference), and the like. Optionally, the scaffold will be coated with, impregnated with, or otherwise adapted to carry a medicament which will be released in the aneurysmal sac after the scaffold is implanted therein. The present invention will primarily rely on stents and grafts which are endoluminally placed to provide the desired blood flow lumen(s) across the aneurysm and to define an aneurysmal space between an outside surface of the scaffold and an inside surface of all or a portion of the aneurysmal wall. As discussed above in the Background section, the aneurysmal space which remains around an aneurysmal scaffold is subject to leakage and in some cases allows for migration of the scaffold from the originally implanted location. Both outcomes are undesirable, and the methods and systems of the present invention will help both seal the aneurysmal space in order to reduce the risk of leakage and help anchor the aneurysmal scaffold in place to reduce the risk of migration.
[0013] The present invention provides for the deployment of one or more expandable structures, such as inflatable balloons or bladders, within the aneurysmal space. The expandable structures are usually placed after deployment of the aneurysmal scaffold and more usually are deployed through the wall of the scaffold into the aneurysmal space. In other instances, however, the space-filling expandable structures may be deployed prior to placement of the aneurysmal scaffold, where such pre-deployed expandable structures may be expanded either before or after deployment of the aneurysmal scaffold. In other instances, the expandable structures of the present invention may be deployed days, weeks, or even longer after an initial endoluminal or other aneurysmal repair. The expandable structures are useful for developing voids which may open around a previously implanted scaffold over time. For such “revision” treatments, the expandable structures may be placed through the aneurysmal scaffold or may be percutaneously placed through the wall of the aneurysm.
[0014] When filling the aneurysmal space after deployment of an aneurysmal scaffold, it is necessary to avoid over pressuring the aneurysmal sac in order to reduce the risk of accidental rupture. The present invention provides different protocols for controlling pressurization within the aneurysmal space as the expandable structure is being expanded. For example, excess expansion medium being fed to one or more of the expandable structures may be selectively bled from the structure if the pressure within the aneurysmal space is excessive. A drain tube or lumen may be connected to the expandable structure while it is being expanded in order to bleed the excess expansion medium. Such selective bleeding could be controlled by a pressure relief valve, a feedback pressure control system, or the like. Alternatively, excessive pressurization within the aneurysmal sac can be controlled by bleeding fluid from the aneurysmal space as the expandable structure is being expanded. Such control could be provided by one or more drain catheters deployed directly into the aneurysmal space and connected to pressure relief valves or active pressure control systems.
[0015] In a first aspect of the present invention, methods are provided for treating an aneurysm in a blood vessel by placing a scaffold across the aneurysm to define an aneurysmal space between an outside surface of the scaffold and an inside surface of the aneurysmal wall. At least one expandable structure is expanded using an expansion medium which passes by or through the scaffold or through the aneurysmal wall to fill at least a portion of the aneurysmal space.
[0016] The scaffold may comprise any conventional vascular scaffold of a type which may be positioned across an aneurysm. For example, the scaffold could comprise a conventional bare metal stent having sufficient length and suitable diameter to be implanted across the aneurysm with a first end anchored in healthy vasculature on one side of the aneurysm and a second end anchored in healthy vasculature on the other side of the aneurysm. Such bare metal stents may be balloon expandable, self-expanding, provide for a ratcheting expansion, or the like. Alternatively, fabric, braid, or other vascular grafts may be anchored in healthy vasculature on either side of the aneurysm, often using barbs, staples, or the like. The graft structures will typically comprise a blood-impermeable wall, and thus the expandable structures will typically be delivered before graft deployment, around a partially deployed graft, or through the aneurysmal wall, as described generally below. In addition to stents and grafts, the present invention can use stent-reinforced graft structures which are typically expanded and anchored within the target blood vessel. Such stent-grafts may also be balloon expandable, self-expanding, or a combination thereof.
[0017] The systems and methods of the present invention may be used to treat aneurysms having a variety of geometries. While the systems and methods are particularly useful for treating aneurysms wherein the enlargement circumscribes the blood vessel (fusiform), such as most aortic aneurysms, they will also be useful for treating various asymmetric aneurysms where the bulge is present over only a portion of the periphery of the blood vessel wall. In all cases, it is generally desirable that the expandable structures occupy at least most and preferably all of the void in the aneurysmal space in order to most effectively inhibit leakage and migration of the scaffold.
[0018] The methods and systems of the present invention are compatible with the use of both single scaffolds and multiple scaffold systems. In treating linear aneurysms, two or more stents, grafts, or other scaffolds may be placed in series in order to span the entire length of the aneurysm. In bifurcated aneurysms, such as abdominal aortic aneurysms, a pair of parallel scaffolds may be placed in the aneurysm and extend from the aorta into each of the iliac branch vessels. Alternatively, bifurcated scaffolds having branch ends may be placed from the aorta into the iliac arteries. When treating such branch vessels, it will also be possible to add stents, cuffs, and other sealing members which extend the length of the scaffold at either end.
[0019] The expandable structures will typically be balloons or other structures which are inflatable with a fluid inflation medium. Such inflatable structures will typically have a fluid impermeable wall which is sufficiently flexible to conform to the aneurysmal wall, the scaffold, and other expandable structure(s) which may be or have been placed in the aneurysmal space. The inflatable structures may be elastic or non-elastic, typically being formed from parylene, polyester (e.g., Dacron®), PET, PTFE, and/or a compliant material, such as silicone, polyurethane, latex, or combinations thereof. Usually, it will be preferred to form at least a portion of the inflatable member partially or entirely from a non-compliant material to enhance conformance of the outer wall of the scaffold to the inner surface of the aneurysm.
[0020] The walls of the expandable structures may consist of a single layer or may comprise multiple layers which are laminated, glued, heat bonded, ultrasonically bonded, or otherwise formed together. Different layers may comprise different materials, including both compliant and/or non-compliant materials. The structure walls may also be reinforced in various ways, including braid reinforcement layers, filament reinforcement layers, and the like.
[0021] The expandable structures of the present invention may also be expanded with non-fluid expansion medium, such as powders, pellets, coils, foams, and the like. In such instances, the expandable structure will not necessarily be formed from an impermeable material, but instead could be formed from lattices, braids, nets, or other permeable or foramenous structures which contain the expansion medium but might permit blood and fluid permeation.
[0022] In some instances, the expandable structure will be extruded in situ, typically at the same time that it is being expanded or inflated with a separate expansion material. Various extrudable polymers exist which can be delivered from a delivery catheter.
[0023] Expanding the expandable structure will usually be performed at least in part using a delivery catheter which both positions and fills the expansion structure within the aneurysmal space. Most commonly, the delivery catheter will be positioned inside of the scaffold and will deliver the expansion medium through the catheter wall. In other instances, however, the delivery catheter may be positioned around one end of the scaffold to permit positioning and filling of the expandable structure before or after the scaffold has been placed. In still further instances, the delivery catheter may be passed through a penetration in the aneurysmal wall to access a void in the aneurysmal space which requires filling.
[0024] In a first exemplary embodiment, the delivery catheter will be used to deliver and position the expandable structure through the scaffold wall after the scaffold has been placed in the aneurysm. The delivery catheter may be passed through a discrete window or opening formed in the scaffold wall which is enlarged relative to other openings and intended particularly for delivering the expandable structure. More typically, however, the delivery catheter will be passed through openings or interstices which are inherently part of the cellular construction of the scaffold. By passing through the cellular openings which are already present, multiple expandable structures may be placed at locations which may be determined during the course of the procedure.
[0025] In alternative protocols, the delivery catheter may be used to place the expandable structure prior to delivery of the scaffold. The scaffold may then be placed so that at least one end of the scaffold is deployed and anchored over the delivery catheter(s). In such instances, the expandable structures will usually be inflated or otherwise expanded after the scaffold is deployed. Alternatively, the expandable structures may be expanded at least partly prior to deployment of the scaffold so long as care is taken not to over pressurize the aneurysmal sac when the scaffold is expanded and implanted.
[0026] In yet another protocol, the delivery catheter may be introduced into the aneurysmal space by passing a cannula or other delivery tube through a penetration in the aneurysmal wall. The cannula may be positioned using thoracoscopic or other minimally invasive techniques in order to access the outside wall of the aneurysm. Such percutaneous deployment of the expandable structures will be particularly suitable for treating patients where a void or expansion of the aneurysmal sac has occurred sometime after a primary treatment.
[0027] Usually, at least two expandable structures will be delivered to substantially fill the aneurysmal space. Often, three, four, five, or even more expandable structures may be delivered. Typically, the treating physician will sequentially deliver multiple expandable structures through the wall of the aneurysmal scaffold while visualizing the aneurysmal space fluoroscopically. A sufficient number of expansion members can then be delivered in order to substantially fill the void within the aneurysmal space, as confirmed by the fluoroscopic visualization. In other instances, two or more expandable structures may be expanded simultaneously, in mixed protocols where expandable structures are sometimes delivered simultaneously and other times delivered sequentially may also be employed.
[0028] In a second aspect of the present invention, systems for treating an aneurysm in a blood vessel comprise a scaffold, and expandable structure, and a delivery catheter. The scaffold may comprise any of the scaffolds generally described above in connection with the methods of the present invention. The delivery catheters will typically comprise a flexible elongate tubular member having at least one lumen therethrough for delivering expansion medium to the expandable structure. In some embodiments, the expandable structure may be initially attached at a distal end of a delivery catheter and the lumen of the delivery catheter used only for delivering the expansion medium to the expandable structure. The expandable structure will be detachable from the delivery catheter after it has been filled and will usually include a self-sealing valve or other attachment port which closes and retains the expansion medium within the structure after detachment of the delivery catheter. In other instances, the delivery catheter may be adapted to deliver both the expandable structure and the expansion medium to the expandable structure. In such instances, the delivery catheter can be used for sequentially delivering two or more expansion structures together with filling of those structures. In still other instances, separate delivery catheters or delivery catheter components may be used for delivering an expandable structure and for filling the expandable structure.
[0029] The systems of the present invention may further comprise a cannula for positioning a delivery catheter and expandable structure percutaneously through the wall of an aneurysm. The cannula will have an axial lumen for containing the expandable structure and/or delivery catheter can be used to access the aneurysm in a conventional manner.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 illustrates a single scaffold placed across an abdominal aortic aneurysm and creating an aneurysmal space around the scaffold.
[0031] FIGS. 2A and 2B illustrate use of a delivery catheter in accordance with the principles of the present invention for positioning and expanding an expandable structure in accordance with the principles of the present invention.
[0032] FIGS. 3 and 4 illustrate use of a single delivery catheter for delivering multiple expandable structures in accordance with the principles of the present invention.
[0033] FIG. 5 illustrates the use of a pair of delivery catheters for delivering multiple expandable structures in accordance with the principles of the present invention.
[0034] FIG. 6 illustrates the use of a pair of delivery catheters for delivering expandable structures through separate parallel scaffolds.
[0035] FIG. 7 illustrates the use of a pair of delivery catheters for delivering multiple expandable structures through a single bifurcated scaffold.
[0036] FIG. 8 illustrates positioning of a valve in an exemplary expandable structure in accordance with the principles of the present invention.
[0037] FIG. 9 illustrates and expandable structure having an axial channel or groove for receiving a deployed scaffold in accordance with the principles of the present invention.
[0038] FIGS. 10A-10E illustrate use of a delivery catheter for extruding pairs of expandable structures in accordance with the principles of the invention.
[0039] FIGS. 11A-11D illustrate delivery of expandable structures where the delivery catheter is placed past one end of a scaffold in accordance with the principles of the present invention.
[0040] FIG. 12 illustrates use of an expandable structure for filling a void region around a double-walled fillable scaffold in accordance with the principles of the present invention.
[0041] FIG. 13 illustrates a cannula which may be used for deploying an expandable structure percutaneously through an aneurysmal wall in accordance with the principles of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0042] Referring to FIG. 1 , in accordance with the principles of the present invention a scaffold 10 is placed within an aneurysm to span the length of the aneurysm between regions of relatively healthy vasculature. Scaffold 10 is illustrated in an abdominal aortic aneurysm AAA and extends from the renal arteries RA to the iliac arteries IA. The scaffold 10 is shown as a bare metal stent which may be balloon expandable or self-expanding within the aneurysm. It will be appreciated, that the scaffold could comprise a more conventional graft structure, a stent-graft structure, and could comprise barbs, hooks, staples, or other elements for anchoring the scaffold within the regions of healthy vasculature. As shown in FIG. 1 , an annular aneurysmal space AS circumferentially surrounds the scaffold 10 . The method and systems of the present invention are intended for at least partially and preferably substantially completely filling the aneurysmal space to reduce the risk of endoleaks and to anchor the scaffold to inhibit migration.
[0043] Referring now to FIGS. 2A and 2B , delivery catheters 12 may be used to both deliver expandable structures 16 and to fill the expandable structures with an expansion medium, for example by using a syringe 20 to deliver the medium through a lumen of the catheter 12 . Most commonly, the distal end 14 of the delivery catheter 12 will be positioned through openings in the cellular structure of the scaffold 10 , as shown in FIG. 2A . Alternatively, as shown in FIG. 2B , a window 18 may be formed within a wall of the scaffold 10 to permit positioning of the distal end 14 of the delivery catheter 12 therethrough. Use of such a window will usually be compatible only with the delivery of single expandable structure 16 which can occupy substantially the entire aneurysmal space AS. Thus, delivery through the normal opening in the cellular structure of a stent or other scaffold 10 will normally be preferred since it allows the physician to deliver and position multiple expandable structures 16 as needed in order to fully occupy the void region of the aneurysmal space AS.
[0044] Use of a single delivery catheter 12 for sequentially positioning a plurality of expandable structures 16 a - 16 c is illustrated in FIG. 3 . A catheter 12 is used to deliver a first expandable structure 16 a , moved and extended out through a different portion of the scaffold 10 , and then used to deliver a second expandable structure 16 b . A third expandable structure 16 c is shown as being inflated and delivered in FIG. 3 . When using a single delivery catheter 12 to deliver multiple expandable structure 16 , it will usually be desirable to employ separate inflatable members with inflation tubes detachably fixed thereto. Thus, the inflatable expansion member 16 can be delivered, inflated with the inflation tube, and then detached and left in place. After withdrawing one inflation tube, a second inflation tube can then be used to deliver a second inflatable expandable structure 16 . Positioning of the expandable structure 16 can be effected by repositioning the delivery catheter 12 and/or extending the inflatable tube (not shown) from the delivery catheter 12 into different regions of the aneurysmal space AS as needed to fill different portions of the space.
[0045] Referring now to FIG. 4 , the catheter 12 of FIG. 3 has been used to deliver additional expandable structures 16 , with a fourth and a fifth expandable structure 16 d and 16 e shown as being deployed. Additional expandable structures 16 will be added until the entire aneurysmal space AS is filled, usually as confirmed under fluoroscopic. A single catheter 12 has been introduced to the aneurysmal space AS through the iliac artery IA.
[0046] Referring now to FIG. 5 , a pair of delivery catheters 12 a and 12 b can be used to simultaneously position two expandable structures 16 . The delivery catheters 12 a and 12 b are introduced through the two iliac arteries IA, and they may be used to both simultaneously and sequentially deliver multiple expandable structures 16 .
[0047] Referring now to FIG. 6 , a pair of delivery catheters 12 a and 12 b can be used simultaneously and/or sequentially deliver multiple expandable structures 16 through a pair of parallel scaffold 22 and 24 . The upper ends of the scaffolds 22 and 24 are positioned in the aorta and anchored above the renal arteries RA, while the lower ends are respectively in the right and left iliac arteries IA. The delivery catheters are introduced through the iliac arteries into the lower ends of the scaffolds 22 and 24 . Similarly, a pair of delivery catheters 12 a and 12 b can be used to deliver multiple expandable structures 16 simultaneously or sequentially through a bifurcated lower end of a bifurcated stent 26 , as shown in FIG. 7 . In all the cases described thus far, the multiple expandable structures 16 are particularly adapted to conform around regions of thrombus T within the aneurysmal space AS.
[0048] The expandable structure 16 can take a variety of forms. As shown in FIG. 8 , expandable structure 16 A comprises an outer wall formed from a flexible material, typically a polymer as described above. A valve structure 30 is provided to detachably secure to the distal end of a delivery catheter or inflation tube. The delivery catheter tube may deliver any one of the expandable media described above, and the valve 30 will usually be self-closing after the delivery catheter inflation tube is detached. As shown in FIG. 9 , and expandable structure 16 B can be shaped from semi-compliant or non-compliant materials to provide a particular filling geometry. The expandable structure 16 B has a C-shaped cross-section which is particularly useful for filling an annular aneurysmal space surrounding a scaffold where the scaffold is received in an axial channel 32 in the expandable structure.
[0049] Referring now to FIGS. 10A to 10E , expandable structures 40 may be extruded around the scaffold 10 . A highly conformable bag may be pushed out from the delivery catheter 12 under pressure from the fill material. As shown in FIG. 10A , a first extrudable expandable structure 40 a is delivered by a first delivery catheter 12 a , so that it expands and conforms to the scaffold 10 , as shown in FIG. 10B . Optionally, a second extrudable expandable structure 40 b may be delivered using a second delivery catheter 12 b , as shown in FIG. 10C . The delivery of extrudable expandable structures may similarly be performed in parallel stents 22 and 24 , as shown in FIG. 10D or in bifurcated stents 26 as shown in FIG. 10E . Once the aneurysmal space AS has been substantially filled, the extrudable expandable structures 40 may be sealed, optionally with a heating element, a clip, an adhesive, or other techniques for terminating the extrusion. The delivery catheters can then be removed, leaving the extruded expandable structures in place.
[0050] As described thus far, the expandable structures 16 have been delivered from a central lumen or passage of the scaffold into the aneurysmal space surrounding the scaffold. As an alternative, the expandable structures may also be delivered by positioning a delivery catheter on the outside of the scaffold, as illustrated generally in FIGS. 11A-11D . Usually, the delivery catheter 12 will be positioned so that the expandable structure 16 is located in the aneurysmal space AS prior to deployment of the scaffold 10 . The expandable structure 16 may then be expanded or partially expanded before placement of the scaffold 10 , but will more usually be expanded after the scaffold 10 has been fully expanded. As shown in FIG. 11A , a single delivery catheter is positioned to deliver a single expandable structure 16 , where the expandable structure 16 is expanded after deployment of a single scaffold 10 . As shown in FIG. 11B , a pair of expandable structures 16 a and 16 b delivered by delivery catheters 12 a and 12 b , respectively, are positioned prior to deployment of the single scaffold 10 . Again, the expandable structure 16 a and 16 b will be expanded after expansion of the scaffold 10 . The use of delivery catheters 12 for delivering single or pairs of expandable structures 16 may also be utilized with parallel scaffolds 22 and 24 , as shown in FIG. 11C , and with bifurcated scaffolds 26 as shown in FIG. 11D . While delivery of only a single or pair of expandable structures 16 is illustrated, it will be appreciated that the delivery catheter 12 , 12 a , or 12 b , could be utilized together with a separate inflation tube for delivering multiple expandable structures through the lumen of the delivery catheter which will remain in place. After the delivery of expandable structures is complete, the delivery catheters 12 may with drawn from the outside of the scaffold 12 , 22 , 24 , or 26 .
[0051] In all deployment protocols described thus far which employ open lattice or mesh scaffolds, it will be appreciated that expansion of the expandable structures within the aneurysmal space may displace fluid or materials present in the aneurysmal space into the lumen of the scaffold. This is advantageous since it reduces the risk of over pressurization of the aneurysmal sac.
[0052] Referring now to FIG. 12 , use of the systems of the present invention for percutaneously accessing and filling a void in an aneurysmal sac after an earlier deployment of a scaffold in sealing system will be described. A double-walled filling structure 50 may be deployed within the abdominal aortic aneurysm AAA, generally as described in prior application Ser. No. 11/413,460, the full disclosure of which has been previously incorporated herein by reference. As the abdominal aortic aneurysm AAA shown in FIG. 12 is quite asymmetric, there may be sometimes be a void region left even after the filling structure 50 has been fully deployed. The present invention provides for percutaneous placement of an expandable structure 52 which is introduced through a penetration formed in the wall of the aneurysm. While shown in connection with the double-walled filling structure 50 , it will be appreciated that such percutaneous introduction of expandable structures may be performed whenever there is a void left at the periphery of the aneurysmal space, or more commonly when such a void occurs sometime after an initial treatment of the aneurysm. The expandable structure 52 may be any of the inflatable or other members described previously, and will typically be introduced using a cannula 54 ( FIG. 13 ) or other tubular introduction device. Cannula 54 carries the expandable structure 52 in a constrained configuration. The expandable structure 52 is connected to an inflation tube 56 or other device for delivering an expansion medium to the expandable structure. Penetration is formed in the wall of the aneurysm by conventional thoracoscopic or other techniques. Once the void is accessed, the cannula may be introduced through the penetration, and the expandable structure 52 advanced out a distal end of the cannula. After the expandable structure is in place, it may be inflated or otherwise expanded through inflation tube 56 . After the expandable structure is fully expanded and/or the void is fully filled, the inflation member 56 may be detached and the expandable structure 52 sealed. Optionally, additional expandable structures may be introduced through the cannula until the entire void region is filled.
[0053] While the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims. | Aneurysms are treated by placing a scaffold across an aneurysmal sac to provide a blood flow lumen therethrough. An aneurysmal space surrounding the scaffold is filled with one or more expandable structures which are simultaneously or sequentially expanded to fill the aneurysmal space and reduce the risk of endoluminal leaks and scaffold migration. The expandable structures are typically inflatable and delivered by delivery catheter, optionally with an inflation tube or structure attached to the expandable structure. | 0 |
FIELD OF THE INVENTION
The present invention relates to integrated circuit manufacture. More particularly, the present invention relates to the post-etch passivation of metalized layers within semiconductors.
BACKGROUND OF THE INVENTION
Solid state devices, including semiconductors and integrated circuit devices (ICs) are manufactured in four distinct stages. They are material preparation, crystal growth and wafer preparation, wafer fabrication, and packaging. Wafer fabrication is the series of processes used to create the semiconductor devices in and on the wafer surface. The polished starting wafers enter fabrication with blank surfaces and exit with the surface covered with hundreds of completed chips.
Wafer fabrication facilities produce billions of chips world-wide, with thousands of different functions and designs. Even with this daunting diversity of device types, the basic processes which are used to form solid state devices are no more than four: layering, patterning, doping, and heat treatment.
Each of these broad processes may be further broken down. One means of patterning one or more layers formed on of a wafer during fabrication is etching. Patterning is often commenced by laying down a mask layer. One type of mask is a photoresist. Etching can be used, in conjunction with other steps such as photoresist deposition, to form a variety of features through one or more layers in an integrated circuit or other solid state device. Some of these layers are metalized, and aluminum is one metal used to form these metalized layers.
The etching of aluminum presents problems that must be overcome in order to reliably produce commercial quantities of solid state devices which are reliable and which achieve the design objectives for the device. During aluminum etching, chlorine is incorporated into the photoresist and a relatively “chlorine-rich” material is deposited on the aluminum sidewalls; this situation is represented graphically in FIG. 1 . The specific composition, thickness, and amount of Cl incorporated in the sidewall deposition is highly dependant on factors such as the type of photoresist and the etch chemistry.
In some cases the sidewall deposition can be relatively thin, e.g. Cl 2 /BCl 3 etching with I-line resist. In other cases the sidewall deposition can be hundreds of angstroms thick, for instance Cl 2 /BCl 3 /CHF 3 etching with DUV resist. For thicker depositions, the typical corrosion passivation processes can result in a situation in which the entire thickness is not depleted of chlorine. Instead, a Cl-depleted region may be formed on an outer layer as a result of the sidewall passivation. This region may be substantially chlorine-free but a “chlorine-rich” rich region exists between the depleted surface and the aluminum line. See FIG. 2 .
In order to limit the deleterious effects of corrosion, especially ongoing corrosion, within the solid state device, one of the steps commonly taken is corrosion passivation. This is especially true of metals which tend to form substantially impermeable oxides, such as aluminum.
In general, corrosion passivation results from allowing the corrosion process to begin while breaking the cycle before a significant amount of corrosion can form. Most prior corrosion passivation procedures depend on a H 2 O-based plasma to react with residual chlorine to form HCl, which is removed from the wafer surface. The photoresist is stripped off with an O 2 -based plasma process either concurrently or in a subsequent processing step. Ideally, this sequence will remove essentially all of the residual chlorine on the wafer. However, it has been observed that such current passivation methodologies may not remove all the chlorine on the surface of a wafer. Accordingly, they may result in a low “corrosion margin”, or the window of time before formation of detectable amounts of corrosion. This is especially true for “next generation” aluminum etch processes which involve DUV photoresists and aluminum etch processes containing CHF 3 or N 2 , all of which result in relatively thick deposition on the aluminum sidewall.
In order to investigate a more effective passivation methodology, it is well to study the formation of “classic” corrosion. An overview of one corrosion mechanism of significant concern in the solid state industry, including a general mechanistic sequence follows. The exact mechanisms for the formation of classic corrosion are complicated and have not been completely elucidated, but a reasonably general mechanistic sequence, with an identification of the critical factors, is presented below.
It is known that substantially any chlorine remaining on the aluminum wafer after the passivation process will result in the formation of corrosion when the wafer is exposed to ambient humidity.
1) Transport of Water to the Wafer Surface: The first step in the formation of corrosion occurs when water from the ambient environment diffuses to the surface of the wafer. The flux of water to the wafer, and the resulting equilibrium surface H 2 O concentration, will be controlled by the absolute concentration of water in the vapor: i.e., the higher the ambient water concentration, the greater the surface concentration of water.
2) H 2 O Diffusion. Before corrosion can form, the water on the surface of the wafer must diffuse to the Cl-rich region. The rate of water diffusion will be effected by temperature. The higher the temperature, the faster the diffusion. The amount of water diffusing into the sidewall will be controlled by the equilibrium concentration of water on the wafer surface. The higher the surface concentration, the larger the H 2 O flux to the corrosion site.
3) The Corrosion Cycle Begins. Water reacts with the residual Cl to form HCl, which further reacts to form corrosion. A typical reaction scheme is presented in Equations1-3:
AlCL 3 +3 H 2 O→Al(OH) 3 +3HCl (I)
Al(OH) 3 +3HCl+3H 2 O→AlCl 3 ·6H 2 O (II)
2AlCl 3 ·6H 2 O→Al 2 O 3 +9H 2 O+6HCl (III)
The rate at which HCl is formed will depend on the concentration of residual chlorine and the amount of water that has diffused through the film. Note that water plays a key role because it acts as a catalyst for the overall corrosion reaction. The rate of each reaction is strongly dependant on the temperature the higher temperature, the faster the reaction. Moreover, while a typical reaction scheme is shown here, other reaction sequences that form corrosion may also be present. The invention taught hereinafter is not necessarily dependent on any one of these reaction sequences.
4) The Corrosion Cycle Accelerates. HCl reacts with pure aluminum to form AL x Cl y , which subsequently reacts with H 2 O to form corrosion and more HCl, see Equation IV below.
3HCl+3H 2 O+Al→AlCl 3 +3H 2 O→Al(OH) 3 +3HCl (IV)
This cycle continues until the corrosion site breaks through the sidewall passivation and continues to grow on the outside of the aluminum line, as shown at FIG. 3 . As the local concentration of water and HCl increases, the amount and rate of corrosion formation also increases. The corrosion cycle will continue for as long as there are present H 2 O, Cl, and Al, which form the reactants. See FIG. 4 .
The typical passivation procedure occurs at conditions that serve to impede the diffusion of water and hence reduce the effectiveness of the passivation process. Specifically, these inefficiencies are as follows:
1) The entire passivation sequence is carried out at low pressure. The typical pressure range s 2-4 Torr. At these low pressures the concentration of water in the chamber is relatively low, which reduces the amount of water transported to the wafer surface, and ultimately lowers the flux of water to the Cl-rich region. This has the effect of slowing the passivation process.
2) The entire passivation sequence is carried out at high wafer temperatures. The wafer temperature range for the typical passivation methodology is 220-275° C. These high temperatures have the effect of driving off H 2 O as well as HCl, which results in a reduction of the amount of water available for participation in the passivation process. This also has the effect of slowing the passivation process.
3) The passivation process is typically a plasma process. The plasma for the typical passivation methodology either consists solely of H 2 O or a mixture with typical photoresist strip gasses including but not limited to O 2 , N 2 , and CF 4 . The products of the plasma process have the effect of oxidizing the metal incorporated into the sidewall passivation during the aluminum etch, which can result in the creation of an “oxidized skin” on the outer surface of the sidewall passivation. See FIG. 2 . This can have the effect of trapping chlorine beneath the skin, thereby setting the stage for future corrosion and decreasing the effectiveness of the H 2 O passivation. This is because the H 2 O must diffuse through the oxidized layer before reacting, and the HCl must diffuse out before it can be removed.
Based on this conceptual understanding, what becomes clear is that temperature and absolute concentration of water in the vapor are critical parameters for the formation of corrosion, and hence for corrosion passivation. Accordingly, it is for the formation of corrosion, and hence for corrosion passivation. Accordingly, it is desirable to control at least one of temperature and absolute concentration to perform a more complete corrosion passivation.
SUMMARY OF THE INVENTION
The present invention teaches a two-step process which maximizes the efficiency of chlorine conversion and removal, and hence corrosion resistance. The two steps thereof are:
Surface Saturation, which preferably occurs at conditions of relatively high pressure and low wafer temperature, with no plasma. The high pressure will maximize the concentration of water in the chamber, while the low wafer temperature will allow the surface of the wafer to become saturated. Surface wafer saturation tends to maximize the rate and amount of water diffusing into the sidewall passivation. The lack of plasma exposure prevents the formation of diffusion-inhibiting “crust” layers. The timing of this step can be varied depending on the amount of residual chlorine present on the wafer, i.e. sidewall passivation thickness.
After surface saturation, a Corrosion Cycle “Quench” is performed where the pressure in the reaction vessel is quickly ramped down, and the wafer temperature is quickly ramped up, again with no plasma. The combination of the pressure drop and the concurrent temperature rise result in the rapid removal of both the water and the HCl from the wafer surface and hence breaks the corrosion cycle. The rate and setpoint which the temperature ramps up to, and the rate and setpoint the pressure ramp down to, represent variables which are used to control how quickly the corrosion cycle is halted. The temperature ramp may be achieved with the use of heat lamps, or some other Rapid Thermal Process methodology, and the pressure ramp controlled, for instance, by controlling the chamber throttle valve or pumping speed.
These and other advantages of the present invention will become apparent upon reading the following detailed descriptions and studying the various figures of the Drawing.
BRIEF DESCRIPTION OF THE DRAWING
For more complete understanding of the present invention, reference is made to the accompanying Drawing in the following Detailed Description of the Invention. In the drawing:
FIG. 1 is a cross section through a sidewall including an aluminum line in an integrated circuit, showing a chlorine-rich area prior to passivation.
FIG. 2 is a cross section through the sidewall including the aluminum line in the integrated circuit, showing a chlorine-depleted layer overlying a chlorine rich passivated area.
FIG. 3 is a cross section through the sidewall including the aluminum line in the integrated circuit, showing the effects of the corrosion cycle on the sidewall.
FIG. 4 is a schematic of the actions of the corrosion cycle applied to an aluminum line in an integrated circuit.
FIG. 5 is a flow chart representation of the process of the present invention.
Reference numbers refer to the same or equivalent parts of the invention throughout the several figures of the Drawing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of this invention is to change the typical passivation step into a two-step process which maximizes the efficiency of chlorine conversion and removal, and hence corrosion resistance. Having reference to FIG. 5, the two steps thereof are discussed as follows:
First Step: Surface Saturation. Step 501 preferably occurs at conditions of relatively high pressure and low wafer temperature, with no plasma. The high pressure will maximize the concentration of water in the chamber, while the low wafer temperature will allow the surface of the wafer to become saturated. Surface wafer saturation tends to maximize the rate and amount of water diffusing into the sidewall passivation. The lack of plasma exposure prevents the formation of diffusion-inhibiting “crust” layers. The timing of this step can be varied depending on the amount of residual chlorine present on the wafer, i.e. sidewall passivation thickness. Thicker passivation would mean a longer saturation time. This step will create the conditions that are the most favorable for initiating the corrosion cycle, which will have the effect of maximizing the efficiency/rate of conversion of chlorine to HCl.
Two separate experiments were performed which clearly indicate that creating a plasma in the corrosion passivation step is not necessary for successful corrosion inhibition. Summaries of the experimental results are as follows:
1) Microwave power experiments. Three corrosion tests were performed at different plasma powers: 1400 W, 700 W, and 0 W, the latter representing no plasma. Upon inspection, no corrosion was observed on any of the wafers. These results, especially the “no plasma” test, represents “proof of principle” that corrosion passivation is achievable without a plasma.
2) Microwave Strip Module Characterization: As part of the initial characterization of the microwave stripper, an experiment was performed on the typical H 2 O passivation process. The goal of the characterization was to obtain trend information for the photoresist strip rate, uniformity of the photoresist strip, and corrosion performance. The analysis of the results of the experiment revealed that the plasma power had no effect on corrosion performance.
The three process “knobs” for performing the present invention are pressure, temperature, and ramp time. While it is contemplated that a wide variety of low process temperatures may be implemented to form the low wafer temperature of step 501 , any temperature above freezing, 0 C., may be implemented. According to another embodiment a range of from 25-60 C. may be used. According to yet another embodiment, substantially any temperature below 275 C. may be utilized, so long as this temperature is lower than the temperature in step 502 , following.
Pressures suitable for performing step 501 are from as low as 1 mTorr, or even lower to as high as 10 atmospheres, or even higher. Again, the principle concern here is that the pressure of step 501 be higher than that at step 502 .
Second step: Corrosion Cycle “Quench”. In step 502 the pressure in the reaction vessel is quickly ramped down, and the wafer temperature is quickly ramped up, again with no plasma. The combination of the pressure drop and the concurrent temperature rise result in the rapid removal of both the water and the HCl from the wafer surface and hence breaks the corrosion cycle. The rate and setpoint which the temperature ramps up to, and the rate and setpoint the pressure ramp down to, represent variables which are used to control how quickly the corrosion cycle is halted. The temperature ramp may be achieved with the use of heat lamps, or some other Rapid Thermal Process methodology, and the pressure ramp controlled, for instance, by controlling the chamber throttle valve or pumping speed.
While it is contemplated that a wide variety of relatively high process temperatures may be implemented to form the high wafer temperature of step 502 , any temperature below about 300 C., may be implemented, so long as the temperature is higher than the temperature of step 501 . According to another embodiment a range of from 25-60 C. may be used. According to yet another embodiment, substantially any temperature above 0 C. may be utilized, so long is this temperature is higher than the temperature in step 501 , preceding.
Pressures suitable for performing step 501 are from as low as 0.1 mTorr, or even lower to as high as 10 atmospheres, or even higher. Again, the principle concern here is that the pressure of step 502 be lower than that at step 501 . The principles of the present invention contemplate a decrease in pressure between steps 501 and 502 by factors as low as 2 or even lower or as high as 10 or even higher.
The ramp time between steps 501 and 502 may be as rapid as 1 second or even lower or as slow as one minute or even higher, or substantially any value therebetween. Examples of the latter include ramp times of between 5 seconds and 45seconds, between 10 seconds and 30 seconds and between 15 seconds and 20 seconds. Ramp times may be limited by equipment capability and the wafer's ability to gain temperature, although no experiments have been conducted with a view to determining minimum or maximum ramp times attainable.
Steps 501 and 502 may advantageously be performed in the same reaction vessel or chamber. Alternatively, the steps may be performed in separate vessels or chambers. Finally, either one or both of steps 501 and 502 may be performed in situ within a vessel or chamber utilized for a preceding or succeeding process step.
After steps 501 and 502 , the photoresist may be stripped via conventional strip chemistries/processes. This new passivation methodology can occur in the same chamber as the photoresist removal. Alternatively, the methodology taught herein may be implemented in a different chamber.
While it is expected that the specific details of any specific two-step methodology performed in accordance with the teachings of the present invention may be application-dependant, it is nevertheless anticipated that the two-step methodology taught herein is superior to the current methodology in passivation efficiency. This translates into throughput gains and/or improved corrosion resistance.
In summary, the main factors which differentiate this invention from the previous corrosion prevention methodologies are as follows: The present invention does not utilize a plasma, where previous methodologies are plasma processes. The present invention involves relatively high process pressures where the previous methodologies are performed at a relatively low process pressures. The present invention utilizes a ramp down of the process pressure where previous methodologies are performed at constant pressure. The present invention utilizes relatively low wafer temperatures where previous methodologies are performed at relatively high wafer temperatures. Finally, the present invention involves a ramp up of the wafer temperature where previous methodologies are performed at substantially constant wafer temperatures.
The present invention has been particularly shown and described with respect to certain preferred embodiments of features thereof. However, it should be readily apparent to those of ordinary skill in the art that various changes and modifications in form and detail may be made without departing from the spirit and scope of the invention as set forth in the appended claims. In particular, the principles of the present invention specifically contemplate the incorporation of one or more of the various features and advantages taught herein on a wide variety of pressures, temperatures, processing equipment, ramp times, wafer designs, and photoresist strip methodologies. Each of these alternatives is specifically contemplated by the principles of the present invention. | A method of improving the post-etch corrosion resistance of aluminum-containing wafers by performing a two-step post-etch passivation sequence which does not involve a plasma. In the first step the pressure is high, relative to typical passivation procedures, and the wafer temperature is relatively low. In the second step, the pressure is ramped down and the wafer temperature is ramped up. This two-step approach results in a more-efficient removal of chlorine from the wafer, and hence improved corrosion resistance. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor device, having a chip-size package structure, and a process for producing the same.
2. Description of the Related Art
A process for producing semiconductor devices comprising assembling semiconductor devices in the wafering step has been developed (Japanese Unexamined Patent Publication (Kokai) No. 10-79362). The process can provide semiconductor devices each having a separate chip-size package structure completed by cutting, and reduce the production costs.
The production process comprises forming a wiring pattern (rewiring pattern), to be connected to electrodes of the semiconductor chip, on an insulating film formed on the semiconductor chip, forming protruded electrodes by plating the wiring pattern, forming a protective film covering the wiring pattern by compression molding, and forming a solder bump for external connection on the end portion of each of the protruded electrodes.
The step of forming a protective film comprises the following procedures.
That is, a top face and a bottom face are heated to about 175° C. A temporary film is absorbed by the top face.
A wafer on which a wiring pattern and protruded electrodes are formed is placed on the bottom face, and a sealing resin is placed on the wafer.
The resin is melted by the heat and pressure of the sealing mold to be spread over the entire wafer, and held within the mold to be cured.
The wafer is taken out of the mold, and the temporary film is peeled off.
A solder bump for external connection is formed on the end portion of each of the protruded electrodes.
However, the conventional process for producing a semiconductor device has been found to have the following problems.
That is, when the process is carried out by compression molding wherein a resin is placed on a wafer, the resin is melted by pressing the resin with a mold, and the molten resin is spread over the entire wafer to form a protective film, the protective film is also placed on the end face of each of the protruded electrodes, and removal of the protective film from the end face becomes incomplete.
Accordingly, when a solder bump 12 is bonded to the end portion of a protruded electrode 10 as shown in FIG. 16, the bond area of the solder bump 12 is reduced by a protective film 14 , and the bond strength becomes insufficient, which causes a problem in reliability.
Moreover, the bonded portion of the solder bump 12 makes an acute angle with the surface of the protruded electrode 12 , which causes the problem that the bump tends to be easily removed by impact.
In addition, the reference numerals 15 , 16 and 18 designate a semiconductor chip, an insulating film formed from a polyimide resin and a rewiring pattern formed on the insulating film 16 , respectively.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a semiconductor device which is excellent in the bond strength of a bump with each of the protruded electrodes and which is highly reliable, and a process for producing the same.
In a semiconductor device according to the present invention wherein a wiring pattern to be connected to an electrode of a semiconductor chip is formed on an insulating film formed on the semiconductor chip surface on which the electrode is formed, protruded electrodes are formed on the wiring pattern, the wiring pattern is covered with a protective film, and a bump for external connection is formed on the end portion of each of the protruded electrodes exposed from the protective film, the bump is formed by bonding the bump to the at least entire end face of each of the protruded electrodes.
Since the bump is bonded to the entire end face of each of the protruded electrodes as described above, the bump is excellent in bond strength.
The bump mentioned above is characterized in that a barrier plated layer is formed on the end face of each of the protruded electrodes, and that the bump is formed in such a manner that the bump is bonded to the entire barrier plated layer.
Since the bump shows good wettability with the barrier plated layer, it is bonded to the entire barrier plated layer.
The protective film is characterized in that the protective film is formed to have a top surface lower than the position at which the bump is bonded to each of the protruded electrodes.
Since the top surface of the protective film is lower than that of the protruded electrodes, the protective film is never placed on the end portion of the protruded electrodes, and the bump is bonded to the entire end face of each of the protruded electrodes.
The protruded electrodes are appropriate when an oxide film is formed on the peripheral surface of each of the protruded electrodes, and when there is a gap between the protective film and the peripheral surface of each of the protruded electrodes.
The protruded electrodes thus become independent of the protective film, and are not influenced thereby even when the coefficient of thermal expansion of the electrodes differs from that of the film. Stress concentration between the protruded electrode and the bump is therefore relaxed, and crack formation and the like, in the bump and in the protective film, can be suppressed.
Furthermore, it is also appropriate in this case to form the protective film in such a manner that the level of the protective film becomes higher than the position at which the bump is bonded to each of the protruded electrodes, and that part of the peripheral surface of the bump is contacted with the protective film.
As a result, a gap between each of the electrodes and the protective film can be closed, and invasion of moisture, etc. can be prevented.
Next, in a process for producing a semiconductor device according to the present invention wherein a wiring pattern to be connected to an electrode of a semiconductor chip is formed on an insulating film formed on the semiconductor chip surface on which the electrode is formed, protruded electrodes are formed on the wiring pattern, the wiring pattern is covered with a protective film, and a bump for external connection is formed on the end portion of each of the protruded electrodes exposed from the protective film, the process comprises the steps of: covering the wiring pattern formed on the insulating film with a resist layer, and forming holes in the resist layer to expose part of the wiring pattern; plating the wiring pattern within the holes to form the protruded electrodes; removing the resist layer; effecting sealing by supplying a resin to the wiring pattern to form a resin layer having a top surface lower than that of the protruded electrodes, thereby forming a protective film; and forming a bump on each of the protruded electrodes in such a manner that the bump is bonded to the at least entire end face of each of the protruded electrodes.
Since the protective film is formed by potting or spin coating to have a top surface lower than that of each of the protruded electrodes, the entire end face of each of the protruded electrodes is exposed, and a bump is bonded to the entire end face, which improves the bond strength of the bump.
Moreover, the process is appropriate when the process comprises plating to form a barrier plated layer on the end face of each of the protruded electrodes, and when the bump is formed in the bump-forming step in such a manner that the bump is bonded to the entire barrier plated layer.
Furthermore, in a process for producing a semiconductor device according to the present invention wherein a wiring pattern to be connected to an electrode of a semiconductor chip is formed on an insulating film formed on the semiconductor chip surface on which the electrode is formed, protruded electrodes are formed on the wiring pattern, the wiring pattern is covered with a protective film, and a bump for external connection is formed on the end portion of each of the protruded electrodes exposed from the protective film, the process comprises the steps of: covering the wiring pattern formed on the insulating film with a resist layer, and forming holes in the resist layer to expose part of the wiring pattern; plating the wiring pattern within the holes to form the protruded electrodes; removing the resist layer; forming the bump on each of the protruded electrodes in such a manner that the bump is bonded to the at least entire end face of each of the protruded electrodes; and effecting sealing, after forming the bump, by supplying a resin to the wiring pattern to form a protective film.
Since the protective film is formed after forming bumps, the bumps each can be formed at a desired position of the protruded electrode, and the bond strength of the bumps can be increased.
Also in this case, the process is appropriate when the process comprises the plating step of forming a barrier plated layer on the end face of each of the protruded electrodes, and when the bump is formed in the bump-forming step in such a manner that the bump is bonded to the entire barrier plated layer.
Furthermore, in a process for producing a semiconductor device according to the present invention wherein a wiring pattern to be connected to an electrode of a semiconductor chip is formed on an insulating film formed on the semiconductor chip surface on which the electrode is formed, protruded electrodes are formed on the wiring pattern, the wiring pattern is covered with a protective film, and a bump for external connection is formed on the end portion of each of the protruded electrodes exposed from the protective film, the process comprises the steps of: covering the wiring pattern formed on the insulating film with a resist layer, and forming holes in the resist layer to expose part of the wiring pattern; plating the wiring pattern within the holes to form the protruded electrodes; removing the resist layer; forming the bump on each of the protruded electrodes in such a manner that the bump is bonded to the at least entire end face of each of the protruded electrodes; forming a photosensitive resist layer to cover the wiring pattern and the protruded electrodes; and effecting photolithography by exposing to light and developing the photosensitive resist layer to form a protective film which covers the wiring pattern and to expose the protruded electrodes.
Since the protective film is formed after forming bumps also in this process, the bumps can be formed without being influenced by the protective film, and the bond strength of the bumps can be increased.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing the step of forming an insulating film on a wafer;
FIG. 2 is a sectional view showing the step of forming a bonded metal layer and a copper layer on an insulating film;
FIG. 3 is a sectional view showing the step of forming a wiring pattern;
FIG. 4 is a sectional view showing the step of forming a protruded electrode;
FIG. 5 is sectional view showing a wafer on which protruded electrodes are formed;
FIG. 6 is a sectional view showing the step of supplying a resin on a wafer in a first embodiment;
FIG. 7 is a sectional view showing the shape of a protruded electrode;
FIG. 8 is a sectional view showing bumps bonded to protruded electrodes, respectively;
FIG. 9 ( a ) and FIG. 9 ( b ) are sectional views each showing the form of a bonded bump;
FIG. 10 is a sectional view showing bumps bonded to protruded electrodes, respectively, in a second embodiment;
FIG. 11 is a sectional view showing the step of supplying a resin on a wafer;
FIG. 12 is a sectional view showing the step of forming a photosensitive resist layer in a third embodiment;
FIG. 13 is a sectional view showing the step of forming a protective film with a photosensitive resist layer;
FIG. 14 is a sectional view showing a gap formed between a protective film and a protruded electrode;
FIG. 15 is a sectional view showing a protrusion formed at the end of a protruded electrode; and
FIG. 16 is a sectional view showing a bump in the prior art.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Appropriate embodiments of the present invention will be explained below in detail based on the attached drawings.
Although a process for forming a rewiring pattern on a wafer is known, the process will be briefly explained by making reference to FIG. 1 to FIG. 4 .
Firstly, as shown in FIG. 1, an insulating film 23 composed of a polyimide resin is formed on a passivation film 21 of a wafer (semiconductor chip) 20 except for the portion for an aluminum electrode 22 .
Secondly, as shown in FIG. 2, a bonded metal layer 25 comprising double layers of titanium and chromium and a copper layer 26 are formed by sputtering.
Next, as shown in FIG. 3, a resist pattern 27 in which the copper layer 26 is exposed in a groove shape in the portion where a wiring pattern (rewiring pattern) is to be formed is formed. A plated film is formed on the copper layer 26 by electroplating of copper while the resist pattern 27 and the copper layer 26 are used as a mask and a conducting layer, respectively, thereby forming a wiring pattern 28 .
The resist pattern 27 is removed.
Next, as shown in FIG. 4, a resist layer 30 is formed on the wiring pattern 28 , and holes 31 are formed in the resist layer 30 to expose part of the wiring pattern 28 .
The wiring pattern 28 within the holes 31 is electroplated with copper to form protruded electrodes 32 .
A barrier plated layer 33 comprising a nickel coating and a gold coating is further formed on the end face of each of the protruded electrodes 32 . The barrier plated layer 33 may also comprise two layer coatings formed with a nickel coating and a palladium coating.
The resist layer 30 is then removed.
The exposed copper layer 26 and the bonded metal layer 25 are removed by etching, thereby isolating the wiring pattern 28 .
The wafer 20 on which the insulating film 23 , the wiring pattern 28 and the protruded electrodes 32 have been formed can thus be obtained (FIG. 5 ).
First Embodiment
Next, as shown in FIG. 6, a resin composed of an epoxy resin, etc. is supplied to the wiring pattern 28 from a nozzle 34 , flattened, and cured to form a protective film 36 . Spin coating is suitable for flattening the resin.
The level of the protective film 36 is made lower than that of the protruded electrodes 32 .
Specifically, when the protruded electrodes 32 are formed by electroplating to make a protrusion, the center of the end face of each of the electrodes becomes protuberant to some extent as shown in FIG. 7 . The protective film 36 is formed in such a manner that the level of the film becomes lower than that of the edge portion of the barrier plated layer 33 .
A solder bump 38 is subsequently formed on each of the protruded electrodes 32 as shown in FIG. 8 .
The solder bump 38 is formed in such a manner that the bump 38 is bonded to the entire barrier plated layer 33 having good wettability (FIG. 9 ( a )). That is, an oxide film is formed on the peripheral surface of the protruded electrode 32 formed with copper. Since the wettability of solder with the oxide film is poor, the solder bump 38 is formed so that the bump is bonded to the entire barrier plated layer 33 . In addition, when a highly active flux is used, the oxide film on the peripheral surface of the protruded electrode 32 is sometimes removed, and the solder bump 38 adheres to the portion where the oxide film has been removed. The state is included in the state where “the bump is bonded to the entire barrier plated layer 33 ” in the present invention (FIG. 9 ( b )).
As explained above, since the bump is formed while the bump is bonded to the entire end face of the protruded electrode 32 , in more detail, the bump is bonded to the entire barrier plated layer, a large bond area is obtained, and the bond strength of the bump 38 can be increased. Moreover, the bond angle made by the solder bump 38 with the protruded electrode does not become an acute angle; therefore, the solder bump is also excellent in strength on impact.
In addition, the entire end face of the protruded electrode 32 designates the entire end face included within the sectional area of the protruded electrode 32 (within the area of the plan view thereof) even when the end face forms a curved surface.
Second Embodiment
FIG. 10 and FIG. 11 show a second embodiment.
In the present embodiment, the solder bumps 38 are firstly formed on the protruded electrodes 32 , respectively, on the wafer 20 shown in FIG. 5, as shown in FIG. 10 .
Similarly to FIG. 9, also in this case, since an oxide film is formed on the peripheral surface of each of the protruded electrodes 32 , the protruded electrodes show poor wettability with solder; therefore, the solder bumps 38 are each determined to be bonded to the entire barrier plated layer 33 .
Next, as shown in FIG. 11, a resin such as an epoxy resin is supplied from a nozzle 34 to the wiring pattern 28 , and cured to form a protective film 36 .
The level of the protective film 36 is arbitrary in this case. That is, since each of the bumps 38 has already been bonded to the protruded electrode 32 to form a necessary bond area, the bond strength of the bumps 38 is not influenced by the protective film 38 .
Third Embodiment
In the present embodiment, the solder bumps 38 are formed on the protruded electrodes 32 , respectively, as shown in FIG. 10 for the second embodiment, and a photosensitive resist layer 40 is formed to cover the wiring pattern 28 and even the top of the solder bumps 38 as shown in FIG. 12 .
Next, as shown in FIG. 13, the photosensitive resist layer 40 is exposed and developed by photolithography to form a protective film 42 which covers the wiring pattern 28 and to disclose the protruded electrodes 32 .
A positive photosensitive resist is used for the photosensitive resist layer 40 . Control of the exposure time can control the depth of exposure, and as a result the thickness of the resist layer, which can be removed by etching, can be controlled.
Furthermore, since the light does not impinge on a portion near the root of each of the solder bumps 38 , the resist layer covering the periphery of the bond portion between each of the solder bumps 38 and the corresponding protruded electrode 32 can be left as shown in FIG. 13, whereby the bond portion can be protected.
The bond strength of the solder bumps 38 can be increased also in the present embodiment.
In each of the embodiments mentioned above, each of the semiconductor devices can of course be completed separately by finally cutting the wafer 20 .
In addition, semiconductor devices can each be completed separately by cutting the wafer first to give separate semiconductor chips, and then following the steps as mentioned above.
In the second embodiment, as shown in FIG. 14, a gap (structure without adhesion) can be formed between the protective film 36 and the peripheral surface of the protruded electrode 32 , depending on the type of resin used.
That is, as explained above, an oxide film is formed on the peripheral surface of the protruded electrode 32 , and some resins show poor wettability with the protruded electrode when the oxide film is formed. As a result, the protective film 36 does not adhere to the peripheral surface of the protruded electrode 32 .
An oxide film may also be positively formed on the peripheral surface of the protruded electrode 32 .
Consequently, the protruded electrode 32 becomes independent of the protective film 36 , and is not influenced thereby even when the coefficient of thermal expansion of the electrode differs from that of the film. Stress concentration in the bond portion between the protruded electrode 32 and the bump 38 is relaxed, and crack formation, and the like, in the bond portion can be suppressed.
Also in this case, it is appropriate to form the protective film 36 in such a manner that its level becomes higher than the position at which the bump 38 is bonded to the protruded electrode 32 , and that part of the peripheral surface of the bump is contacted with the protective film 36 (FIG. 14 ).
As a result, the gap between the protruded electrode 32 and the protective film 36 can be closed, and invasion of moisture, and the like, can be prevented.
FIG. 15 shows another embodiment of the end face shape of the protruded electrode 32 .
In the present embodiment, the end face central portion of the protruded electrode 32 has a still more protuberant shape (protruded portion 32 a).
In order to form such a protruded portion 32 a, the following procedure is recommended. A split 28 a is adhered to the wiring pattern 28 when the protruded electrode 32 is to be formed by plating, and the protruded electrode 32 is formed on the wiring pattern 28 including the slip 28 a by plating. Since the plated coating is formed to have an approximately uniform thickness, the protruded portion 32 a corresponding to the split 28 can be formed.
The split 28 a can be formed by plating during the step of forming the wiring pattern 28 .
Formation of such a protruded portion 32 a can increase the end face area of the protruded electrode 32 , which further increases the bond strength of the bump 38 .
The present invention has been explained above in various ways by making reference to appropriate embodiments. However, the present invention is not restricted to the embodiments, and many modifications of the present invention are naturally possible so long as the modifications do not depart from the spirit and the scope of the invention.
According to the semiconductor device and the production process of the present invention, a semiconductor device excellent in the bond strength of the bumps can be provided. | A semiconductor device excellent in bonding strength of bumps with respective protruded electrodes and having high reliability wherein a wiring pattern 28 to be connected to an electrode 22 of a semiconductor chip 20 is formed on an insulting film 23 formed on the semiconductor chip 20 in which the electrode 20 is formed, protruded electrodes 32 are formed on the wiring pattern 28 , the wiring pattern 28 is covered with a protective film 36 , and a bump 38 for external connection is formed on the end portion of each of the protruded electrodes 32 exposed from the protective film 36 , the bump 38 is formed in such a manner that the bump is bonded to the at least entire end face of each of the protruded electrodes 32. | 7 |
This application is a national phase application filed under 35 USC §371 of PCT Application No. PCT/US2009/038393 with an International filing date of Mar. 26, 2009 which claims priority of U.S. Provisional Application Ser. No. 61/039,758 filed on Mar. 26, 2008. Each of these applications is herein incorporated by reference in their entirety for all purposes.
FIELD OF INVENTION
The subject invention is directed to systems and methods for the production of materials such as polysilicon via chemical vapor deposition in a reactor. More particularly, the subject invention relates to systems and methods for distributing gas to improve flow patterns in a chemical vapor deposition reactor using a silicon standpipe.
DESCRIPTION OF THE RELATED ART
Chemical vapor deposition (CVD) refers to reactions usually occurring in a reaction chamber that involve depositing a solid material from a gaseous phase. CVD can be used to produce high-purity, high-performance, solid materials such as polysilicon, silicon dioxide, and silicon nitride, for example. In the semiconductor and photovoltaic industries, CVD is often used to produce thin films and bulk semiconductor materials. For example, heated surfaces can be exposed to one or more gases. As the gases are delivered into the reaction chamber, they come into contact with heated surfaces. Once this occurs, reactions or decomposition of the gases then occurs forming a solid phase, which is deposited onto the substrate surface to produce the desired material. Critical to this process is the gas flow pattern which influences the rate at which these reactions will take place and the quality of the products.
In polysilicon chemical vapor deposition processes, for example, polycrystalline silicon can be deposited from silane (SiH 4 ), dichlorosilane (SiH 2 Cl 2 ), trichlorosilane (SiHCl 3 ), and tetrachlorosilane (SiCl 4 ) according to the respective reactions. These reactions are usually performed in a vacuum or a pressured CVD reactor, with either pure silicon-containing feedstock, or a mixture of silicon containing feedstock with other gases. The required temperatures for the reactions range from hundreds to over one thousand degrees Celsius. Polysilicon may also be grown directly with doping, if gases such as phosphine, arsine or diborane are added to the CVD chamber.
Gas flow pattern is therefore crucial not only to the growth of polysilicon and other materials, but it also impacts the production rate, product quality, and energy consumption of the overall CVD reactor system.
SUMMARY OF THE INVENTION
The subject invention relates to systems and methods for distributing gas in a chemical vapor deposition reactor, in particular, for improving gas flow in a CVD reactor. Thus, the subject invention can be used to increase efficiency of reactions within CVD reaction chambers, increase the output of solid deposit, improve product quality, and reduce overall operating costs. Also encompassed by the subject invention is that silicon deposited on standpipes in a CVD reactor can be used as additional polysilicon product.
In a reactor system and method according to the subject invention, in particular, a CVD reactor system and method, a standpipe is utilized. The standpipe can be used to inject various reactants into a reaction chamber. The standpipe preferably is made of silicon or other materials. These materials include, without limitation: metals, graphite, silicon carbide, and other suitable materials. The length of the standpipe can range from about 1-2 centimeters up to about a few meters depending on the application. The diameter of the pipe can range from about 1-2 millimeters up to tenths of centimeters depending on the gas flow rate. The thickness of the wall preferably is about 0.1 to about 5.0 millimeters.
The reactor system of the subject invention includes a reaction chamber having at least a base plate fixed within the reaction chamber and an enclosure operably connected to the base plate. One or more filaments are attached to the base plate within the chamber upon which various reactant gases are deposited during a chemical vapor deposition cycle. The filament may be a silicon filament or other desired solid to be fabricated. At least one gas inlet and one gas outlet are connected to the reaction chamber to allow gas flow through the reaction chamber. A window portion or viewing port for viewing an internal portion of the chamber also can be provided. An electrical current source preferably is connected to ends of the filament via electrical feedthroughs in the base plate for supplying a current to heat the filament directly during a CVD reaction cycle. A cooling system for lowering a temperature of the chemical vapor deposition system also can be employed having at least one fluid inlet and at least one fluid outlet.
The standpipe according to the subject invention preferably is operably connected to the at least one gas inlet for injecting gas flow to the reaction chamber. The standpipe preferably includes a nozzle coupler and a pipe body. The length and diameter of the pipe body can be selected based on at least a desired gas flow rate. The nozzle coupler further can include a sealing device such as a gasket for sealing the pipe body to the at least one gas inlet. The standpipe preferably has at least one injection tube within the chamber for distributing a process gas flow. The dimensions of the at least one injection tube are based on a desired flow rate. The injection tube material can be made of silicon or another material.
These and other aspects and advantages of the subject invention will become more readily apparent from the following description of the preferred embodiments taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
So that those skilled in the art to which the subject invention appertains will readily understand how to make and use the method and device of the subject invention without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to certain figures, wherein:
FIG. 1 is a perspective view of a reaction chamber system of the subject invention;
FIG. 2 is an internal perspective view of the reaction chamber of FIG. 1 ;
FIG. 3A is an enlarged cutaway view of a standpipe according to the subject invention;
FIG. 3B is a detailed view of a nozzle coupler attached to a pipe body of the standpipe of FIG. 3A ;
FIG. 3C is an enlarged view of a gasket of the nozzle coupler depicted in FIG. 3B ; and
FIG. 4 is a partial cross-sectional view of the reaction chamber system of the subject invention incorporating multiple standpipes.
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the subject invention are described below with reference to the accompanying drawings, in which like reference numerals represent the same or similar elements.
The subject invention relates to systems and methods for distributing gas in a reactor, in particular, for improving gas flow in a chemical vapor deposition (CVD) reactor. In particular, the subject invention is directed to a system and method for distributing gas in a CVD reactor using a standpipe. The benefits and advantages of the subject invention include, but are not limited to, increased production rates of a solid deposit (e.g. polysilicon), decreased energy consumption, and reduced overall operating costs. While the disclosure of the subject invention is directed toward an exemplary polysilicon CVD reactor system, the system and methods of the subject invention can be applied to any CVD reactor system for which increased gas distribution and improved gas flow patterns are desired, or any reactor system generally.
In an exemplary application, trichlorosilane gas reacts on rods or silicon tube filaments within a reaction chamber to form polysilicon deposits on the thin rods or filaments. The subject invention is not restricted to CVD reactors using polysilicon deposition involving a reaction of trichlorosilane but can be used for reactions involving silane, dichlorosilane, silicon tetrachloride, or other derivatives or combinations of gases, for example, by using thin rods or filaments with large surface area geometries and similar electrical resistivity properties in accordance with the invention. Filaments of various shapes and configurations can be utilized, for example, those disclosed in U.S. Patent Application Publication US 2007/0251455, which is incorporated herein by reference.
Referring to FIGS. 1 and 2 , a chemical vapor deposition (CVD) reactor is shown, in which polysilicon is deposited onto thin rods or filaments according to the subject invention. A reactor system 10 includes a reaction chamber 12 having a base plate 30 , a gas inlet nozzle 24 or process flange, a gas outlet nozzle 22 or exhaust flange, and electrical feedthroughs or conductors 20 for providing a current to directly heat one or more filaments 28 within the reaction chamber 12 , as shown in FIG. 2 . A fluid inlet nozzle 18 and a fluid outlet nozzle 14 are connected to a cooling system for providing fluid to the reaction chamber 10 . In addition, a viewing port 16 or sight glass preferably allows visual inspection of the interior of the reaction chamber 12 , and can optionally be used to obtain temperature measurements inside the reaction chamber 12 .
According to a preferred embodiment of the subject invention as depicted in FIGS. 1 and 2 , the reactor system 10 is configured for bulk production of polysilicon. The system includes the base plate 30 that may, for example, be a single plate or multiple opposing plates, preferably configured with filament supports, and an enclosure attachable to the base plate 30 so as to form a deposition chamber. As used herein, the term “enclosure” refers to an inside of the reaction chamber 12 , where a CVD process can occur.
One or more silicon filaments 28 preferably are disposed within the reaction chamber 12 on filament supports (not shown), and an electrical current source is connectible to both ends of the filaments 28 via electrical feedthroughs 20 in the base plate 30 , for supplying a current to directly heat the filaments. Further provided is at least one gas inlet nozzle 24 in the base plate 30 connectible to a source of silicon-containing gas, for example, and a gas outlet nozzle 22 in the base plate 30 whereby gas may be released from the reaction chamber 12 .
Referring to FIG. 2 , an exemplary standpipe 42 structure is shown, in which a pipe body 44 preferably is operably connected to at least one gas inlet nozzle 24 for injecting various gases into the reaction chamber 12 in conjunction with a CVD reaction occurring in the reaction chamber 12 (see also FIG. 3A ). Although a single injection tube 42 is depicted in FIG. 2 , one or more standpipes can be included in a reaction chamber. For example, referring to FIG. 4 , the single standpipe can be replaced by standpipes 42 . The dimensions of each standpipe or injection tube 42 may vary from about 1-2 cm in length up to a few meters, and about 1-2 mm in diameter to tenths of centimeters, depending upon a desired gas flow design.
The one or more standpipes 42 preferably are used to inject one or more gases to various parts of the reaction chamber 12 , depending upon a desired flow pattern. The standpipe(s) 42 can be attached to the reactor by any known installation mechanism, for example, by screwing a pipe body 44 into an inlet nozzle coupler 25 of the reaction chamber 12 (see FIGS. 3A-3C , as described herein). Because gas flow patterns can be crucial to the growth, production rate, product quality, and energy consumption of polysilicon, the subject invention can be applied to polysilicon manufacturing processes and any other processes that involve silicon or silicon compound deposition. Specifically, it can also be applied to processes where corrosion, contamination, and deposition can occur on the pipe and other shapes of components.
Referring again to FIGS. 3A-3C , various components of the standpipe 42 preferably are made of silicon pipe. Silicon is used as an alternative to non-silicon materials such as stainless steel or other metals that can cause corrosion, contamination, melting and unwanted silicon deposition within the pipe body 44 . At one end of the pipe body 44 , the material from which the pipe body 44 is made is fused with materials that can be machined. These materials include metals, graphite, silicon carbide, and any other suitable material. At the other end, as shown in FIGS. 3A-3C , the pipe body 44 preferably is attached to the nozzle coupler 25 having an appropriate diameter. The nozzle coupler 25 preferably is formed with a gasket 26 for providing an airtight seal between the gas inlet nozzle 24 and a standpipe gas supply source. The length of the pipe body 44 can range from about a few centimeters to about a few meters depending on the application. The diameter of the pipe body 44 can range from about a few millimeters to tenths of centimeters depending on the gas flow rate. The thickness of the pipe body 44 wall preferably is on the order of about a few millimeters or less. The pipe body 44 preferably is made of silicon.
A method for depositing a material in a reactor can include steps of: providing a reaction chamber including at least a base plate fixed within the reaction chamber and an enclosure operably connected to the base plate; attaching at least one filament to the base plate; connecting an electrical current source to the reaction chamber for supplying a current to the filament; connecting a gas source to the reaction chamber to allow gas through the reaction chamber; connecting a standpipe to the gas source for distributing a gas flow within the reaction chamber; and operating the reactor to deposit the material on the at least one filament in the reaction chamber.
An additional benefit of a standpipe of the subject invention is that it can be reused or recycled. During the gas injection process, silicon is deposited on the pipe body 44 . Once the silicon builds up, the silicon can be removed from the pipe bases and used as silicon product.
Although the subject invention has been described with respect to preferred embodiments, those skilled in the art will readily appreciated that changes or modifications thereto may be made without departing from the spirit or scope of the subject invention as defined by the appended claims.
INCORPORATION BY REFERENCE
The entire contents of all patents, published patent applications and other references cited herein are hereby expressly incorporated herein in their entireties by reference. | Systems and methods for the production of polysilicon or another material via chemical vapor deposition in a reactor are provided in which gas is distributed using a silicon standpipe. The silicon standpipe can be attached to the reactor system using a nozzle coupler such that precursor gases may be injected to various portions of the reaction chamber. As a result, gas flow can be improved throughout the reactor chamber, which can increase the yield of polysilicon, improve the quality of polysilicon, and reduce the consumption of energy. | 2 |
TECHNICAL FIELD
The field of the invention is that of forming a plate capacitor having a set of horizontal conductive plates separated by a dielectric (MIM-CAP).
BACKGROUND OF THE INVENTION
High performance (high Q-value) metal-insulator-metal capacitor (MIM cap) is one of the essential passive devices in RF/Analog circuitry. In order to achieve high-Q value, low resistance metal plates are typically used. In prior work, the bottom plate of a metal-insulator-metal (MIM) capacitor is typically made of back end of the line (BEOL) aluminum metal wire on the xth level of the back end (zero-cost). An additional photolithography mask is used for MIM cap top plate formation. This additional top plate mask leads to extra wafer processing cost of about $25/wafer. In the advanced CMOS technologies with Cu BEOL, up to three masks are employed to create high-Q MIM capacitors.
In an effort to reduce cost, vertical parallel plate capacitors (VPP) have been recently developed/introduced in the advanced Analog/RF CMOS technologies. VPPs capacitor plates are made of BEOL Mx wire fingers and vias. Due to scaling of BEOL wiring width and spacing, the capacitance density of VPP becomes appreciable for technologies with minimum features smaller than 0.25 um. However, the performance of a VPP capacitor is limited because of the high resistance associated with metal fingers/vias, which is particularly troublesome for high frequency application.
As a result, a high performance MIM capacitor is still desirable & needed for Analog/RF CMOS technologies.
SUMMARY OF THE INVENTION
The present invention utilizes BEOL wide Cu planes as MIM capacitor electrodes and the existing inter-level dielectric layers as MIM dielectric films; i.e. the thickness of the capacitor plates and of the dielectric is the same in the capacitor as in the rest of the circuit.
The Mx electrodes are tied together to create a parallel plate capacitor. As a result, the resistance of MIM plates according to the present invention is extremely low, which leads to a high performance MIM capacitor.
The capacitance density for the invented MIM increases as the inter-level dielectric films become thinner for more advanced technologies. Moreover, more BEOL metal wiring levels are employed for advanced technologies, which can lead to higher capacitance density for the present invention because more metal levels can be connected together.
To further enhance capacitance density of this zero-cost high-Q MIM capacitor, Vx vias are added through Mx perforation holes (through-vias). The use of through-vias increases capacitive coupling and reduces/eliminates additional wiring area needed for MIM cap plate connection, which again leads to cap density enhancement.
An Ansoft Q3D simulation indicates that capacitance density improvement of greater than 30% is possible compared with through-via practice.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross sectional view of a MIM-Cap with solid plates in the capacitor.
FIG. 2 shows cross sectional view of the same set of plates having perforations.
FIG. 3 shows the plates of FIG. 2 with the holes offset.
FIG. 4 shows the plates with the plates of one polarity being connected by vertical conductors.
FIG. 5 shows the plates with vertical connectors connecting all the plates of each polarity.
FIG. 6 shows a detail of the connection between vertical connectors on adjacent levels.
DETAILED DESCRIPTION
FIG. 1 shows a set of solid plates 50 connected alternately by vertical connection bars 56 . An important feature of this structure compared with prior MIM capacitors is that the thickness 12 of the dielectric between the plates is greater than before because the thickness 12 is the thickness 16 of the back end levels minus the thickness 14 of the interconnects on that back end level; e.g. if the total thickness of the level is 0.5 microns and the thickness of the interconnect on that level is 0.25 microns, then the thickness 12 of the dielectric is also 0.25 microns. Dashed line 10 indicates the top surface of a layer in the back end. A level in the back end containing a capacitor plate will be referred to as a capacitor level. The foregoing means that the capacitance per unit area (capacitance density) is reduced, but that is more than compensated for by the improved reliability provided by the invention. Box 5 represents schematically interconnections on the levels of the BEOL and the remainder of the integrated circuit.
Fabrication of the invented high-Q MIM is fully compatible with Cu BEOL processing. The plates are deposited in apertures in the interlevel dielectric simultaneously with the other interconnects on that level. The blocks labeled 56 that connect the plates of each polarity are schematic representations. They may be vertical bars of metal, vertically aligned damascene conductors, regular interconnects, or any other structure. Preferably, they are vertically aligned dual damascene structures, so that no additional masks or processing steps are needed. No additional processing steps are added in this invented high-Q MIM. An estimate of the capacitance density for six levels of thin metal wire BEOL in 65 nm technology results in cap density of 0.88 fF/μm 2 when no perforation is assumed.
This no perforation assumption is valid for MIMs that require small plates. When MIM plates become large (approximately 20 microns on edge), perforating of copper plates is necessary in order to achieve uniform copper plate thickness. Significant copper plate thinning is expected when large non-perforated Cu plates are used due to the fast Cu polish rate associated with large plates during CMP processing.
However, the capacitance density loss due to perforation is limited. Based on an Ansoft Q3D simulation using design information for a known process using 90 nm ground rules, the loss of capacitance density from perforation is only about ⅓ of the perforation density (for example, the capacitance reduction comparing 38% perforation to no perforation is only 11.5%).
FIG. 2 shows the same plates, illustratively having an area 30 micron 2 while the overlap area is 25 micron 2 , with the addition of a set of holes 51 that are aligned vertically in each plate, regardless of polarity. The holes 51 are separated by solid portions 52 of the plates. Illustratively, the overlap area of the plates of the two polarities is 25 microns 2 and the 30 holes are 0.42 microns by 0.42 microns. The local hole density is 17.6%.
FIG. 3 shows an alternative version in which the holes on alternate plates are staggered, so that a hole 51 on a plate of one polarity is aligned vertically with a solid portion 52 of the plate immediately above and below.
FIG. 4 shows the same hole arrangement as FIG. 3 , but with the addition of 0.14×0.14 micron vertical conductive members (vias) 53 connecting vertically one polarity of plates, whether positive or negative.
FIG. 5 shows the addition of another set of vias 53 to the opposite polarity of plates, so that all plates are connected to plates of the same polarity.
FIG. 6 illustrates a detail of the vertical connectors 53 . Plates 50 -A belong to one of the first and second sets of plates. Plate 50 -B belongs to the other set of plates. Plates 50 are formed by the same damascene technique, well known to those skilled in the art, that forms the other interconnects on this level. Vertical members 53 -A are formed using the dual damascene technique simultaneously with plates 50 -A. At the center of the Figure, plate 50 -B is formed using the same damascene technique and simultaneously member 53 -B is formed in aperture 51 and isolated from plate 50 -B. Optionally, the top of member 53 -B is widened, so that alignment tolerance is provided for the connection with upper member 53 -A. The width of the widened member will be determined by the width of aperture 51 and the ground rules for the gap between 53 -B and the walls of plate 50 -B.
TABLE
Comparison of Capacitance Density
Total
Density
Capaci-
Cap.
Ratio to
Area
tance
Density
Structure
FIG.
Structure Description
μm 2
(fF)
(fF/μm 2 )
1
1
No Perforations
30
16.9779
0.566
N/A
2
18% perf., holes aligned
30
16.2798
0.543
0.959
3
18% perf., holes
30
15.9160
0.531
0.938
staggered
4
18% perf., w/vert. vias,
30
19.3063
0.644
1.138
half plates staggered
5
18% perf., w/vert. vias,
30
22.4531
0.748
1.322
all plates connected
6
38% perf., holes aligned
30
15.0257
0.501
0.885
In all cases in Table I, the overlap area of the plates is 25 micron 2 .
As can be seen in Table I, the perforated but unconnected version of FIG. 2 has 4.1% less capacitance density than the version of FIG. 1 .
Similarly, the perforated and unconnected version of FIG. 3 also has less capacitance density than the embodiment of FIG. 1 . The aligned version of FIG. 1 benefits from the edge capacitance of the holes.
Connecting the vias improves the capacitance ratio substantially, as well as taking up less area after the removal of the vertical connection bars 56 .
As can be seen from example 6 from table I, more perforation in copper plates results in lower capacitance. However, the loss in capacitance is much smaller than one skilled in the art would expect. When copper plates are perforated at 38%, the capacitance loss is approximately 11.5%.
The Figures show an even number of plates in the capacitor. Those skilled in the art will understand that an odd number of plates may also be used, so that the top and bottom plates will have the same polarity, e.g. ground.
While the invention has been described in terms of a single preferred embodiment, those skilled in the art will recognize that the invention can be practiced in various versions within the spirit and scope of the following claims. | A parallel plate capacitor formed in the back end of an integrated circuit employs conductive capacitor plates that are formed simultaneously with the other interconnects on that level of the back end (having the same material, thickness, etc). The capacitor plates are set into the interlevel dielectric using the same process as the other interconnects on that level of the back end (preferably dual damascene). Some versions of the capacitors have perforations in the plates and vertical conductive members connecting all plates of the same polarity, thereby increasing reliability, saving space and increasing the capacitive density compared with solid plates. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to the field of roulette and other casino oriented table games where wagering occurs. Roulette is one of the most popular and well-known casino games steeped in tradition and excitement. In such game, a wheel with colored and numbered areas, e.g., depressions, delineated cages, etc., is spun on its vertical axis after which a ball is introduced upon the moving rotating wheel surface until the ball ultimately comes to rest upon one of such numbered areas.
It is well recognized that as the wheel slows in speed and the movement of the ball moving and/or bouncing along the wheel's surface slows as well, observers, e.g., those bettors playing the game, have a better idea, that is, heightened odds, of choosing which of the numbered or colored areas the ball will ultimately come to rest upon thus determining the winner. The casino employee, dealer or croupier overseeing the table normally controls the movement when no more bets may be placed on the outcome of where the ball will rest and this call or decision is made on the basis of experience and judgment and preferably before the wheel slows to a point where the players can see where or which area of the wheel the ball is going to ultimately rest upon. In other words, the dealer or croupier that is overseeing the table has to not only judge when to terminate further betting based on the speed of the rotating wheel and to some extent the speed and other ball movement, but the croupier must also rule as to whether or not any of the players, i.e., bettors, have improperly placed or withdrawn bets after the “No More Bets” verbal announcement is made. The croupier thus has to observe the ball, the wheel, their relative speeds and movements as well as simultaneously observe whether any bets were made, withdrawn or modified after the “No More Bets” announcement was made.
Although croupiers are skilled, the above duties are demanding and should be carried out in a professional but exciting manner that lends enjoyment to the overall wagering experience. It would, accordingly, be advantageous to provide a system which assists the croupier in his or her duties, e.g., one that would match the wheel's speed to a predetermined speed based on prior experience to a programmed “No More Bets” announcement by a recorded voice or other signal and/or an audible or visual cue to the croupier to make the No More Bets” announcement. Such a system would reduce the croupier's work load, and the casino management could better control the odds by selecting the predetermined wheel speed level at which the “No More Bets” announcement would be made, e.g., the higher the wheel speed, the less likely players could get any feel for where the ball was going thus increasing the odds or at least moving the odds to a point of pure change and vice versa by lowering the predetermined wheel speed.
Another feature of a casino style roulette table is that there is a designated betting area generally rectangular in shape and with a defined perimeter and divided with generally square or rectangular betting areas corresponding to the roulette wheel's numbers and colors and on which betting areas the players place chips in order to register their bets on the outcome of the wheel spin. The players sit adjacent this betting area while the croupier generally sits or stands across from the players and the wheel at the other tableside. Players may place, modify or remove chips at any time prior to the “No More Bets” call by either having the croupier do so or by actually moving their hands across the periphery of the betting area and manipulating the chips into or away from the individual betting areas. Obviously, the croupier has to closely monitor these player actions and be sure no betting takes place after the “No More Bets” call. Thus, anything that would help the croupier perform this duty would be beneficial.
As previously indicated, roulette is a traditional game and actual physical changes to the wheel, the ball or the manner the game is played probably would not be well received; however, features which could add excitement, inform the players about current or upcoming casino events or simply pure advertising that does not interfere with the playing of each wheel spin would generally be welcomed by the players and beneficial to the casino especially if such included paid advertisements. Thus, devising an information and advertisement roulette feature would be advantageous to both the players and the casino as well.
It is, therefore, an object of the present invention to provide a hardware and operational system that addresses the above-indicated concerns to improve the croupier's consistency and monitoring performance and add excitement to the game without detracting from its tradition.
It is also another object of the present invention to incorporate means for determining the ball and/or wheel speed in roulette gaming and to utilize such means in a system for announcing the “No More Bets” cut off.
A still further object of the present invention is to correlate the traditional oral “No More Bets” announcement with a visible announcement display on the betting table itself.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings which illustrate the best mode presently contemplated for carrying out the present invention:
FIG. 1 is a stylized top plan view of a roulette table and wheel incorporating the features of the present invention; and
FIG. 2 is an elevational view of the roulette table and wheel of FIG. 1 as well as a portion of the game room in which such roulette table is housed and showing in particular the laser control unit of the present invention installed in the casino room ceiling and preferably visible to the players at such table.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Players choose or select with number/numbers to place their wager upon the roulette table's betting area. As the dealer or croupier D spins the roulette ball 2 a and the roulette wheel 2 , sensors 3 either positioned within the wheel or outside the wheel detect the ball speed. As the ball revolves around the wheel, players located proximal to the table, e.g., at positions 10 through 16 are placing their bets. Also while bets are being placed, the laser control unit 5 is producing a visible laser display 6 onto a designated area 8 on the roulette table 1 . Low power diode laser systems are commercially available and are suitable for the present purpose, e.g., lasers in the 400 to 700 nanometer range are safe and reliable for the casino's indoor environment.
When the ball slows down to a predetermined speed, the sensor 3 will send a command via a wired connection to the display control computer 4 preferably mounted under the table 1 . The display control computer will send via radio frequency or infrared wireless technology a command for “No More Bets” to the laser control unit 5 . The laser control will outline via a visible beam 6 to the roulette table's betting area 7 a visible message that “No More Bets” are allowed. This message continues to be displayed until the ball permanently falls onto and rests upon the receiving cup or depression of the wheel or cage on the roulette wheel 2 . When the ball falls on such a number on the wheel, the sensors 3 within said wheel sends the ball's position to the display control computer 4 within fractions of a second. The command or ball's position is then sent instantly via infrared or wireless technology to the laser control unit 5 . The laser control unit then produces a visible laser beam to the game table betting area and highlights the winning number as well as all other possible winning combinations. The winning number and combinations can remain highlighted until the ball is removed or by a manual switch device.
The computer 4 may incorporate a sensor for determining the wheel's speed and the ball's position and speed relative to the wheel such that the predetermined speed at which the “No More Bets” signal should be displayed can be determined and repeated during play. Such a sensor is described in U.S. Pat. No. 5,836,583 to Towers and assigned to Technical Casino Services Ltd. of the United Kingdom and the disclosure thereof is hereby incorporated into the present Specification by such specific reference thereto. It should be apparent that the speed of the wheel and/or the speed and motion of the ball or any combination thereof can be used to determine the “predetermined speed” which triggers the above sequences. The casino management by empirical studies can make such predetermined speed and such can be varied dependent on the circumstances of the playing environment, e.g., under normal casino rules, the predetermined speed would be higher than at perhaps a charity event—the important consideration being that the predetermined speed can be varied.
A further feature that is preferably incorporated into the system of the present invention is that the laser upon the “No More Bets” announcement will illuminate the periphery 7 a , of the betting area 7 either by a broadband-shaped circumferential beam which may pulse or by a single light beam which quickly and repeatedly circumambulates the periphery 7 a of the betting area 7 or at least that portion thereof adjacent the players and may alternatively move back and forth along the betting area adjacent the players. This laser lighting beam effect will better enable the croupier to sense motion across the betting area periphery, e.g., caused by bettors improperly adjusting their bets by moving their hands or objects into the betting area.
The preceding system may also be accompanied by a manual system whereby all functions of operating and controlling the laser display are managed by the dealer. As the dealer places the ball on the roulette wheel, the dealer will press the display button on a custom designed keypad. The display computer will then send the message to the laser control unit. The laser control unit then, in turn, presents the display message on the gaming table. When the ball revolving around the wheel slows to the predetermined speed, the dealer will then select the “No More Bets” button on the custom keypad. This will send a command to the laser control unit to highlight the gaming area with the “No More Bets” laser display. When the ball has fallen onto a number within the roulette wheel, the dealer will select the corresponding number on the custom keypad. The laser control unit will then highlight the winning number as well as all other possible winning combinations. The laser will continue to display the winning number and combinations while the dealer is collecting the wagers and makes the payouts to the winning players. The custom keypad also has been designed with calibration and lock buttons to enable the dealer to calibrate the laser to the table layout area at anytime when necessary.
by introducing this technology, the invention will provide for a safer, fairer and add an exciting element to the age old Roulette game. The system does not introduce any physical elements that will hinder play in any way. In fact, there are no moving parts introduced to the game at all. The game remains virtually untouched. The system can also be expanded to include other table games should the casino wish to protect a specific area or zone on a gaming table.
Laser Roulette will add a new element of excitement to the Roulette gaming experience. Laser Roulette will provide for a higher level of security thus making for a more fair and honest game for both the casino and the patron. Laser Roulette will bring more new players to the roulette experience due to the system's ability to show all players the additional winning possibilities they may otherwise not be aware of. The casino is in business to provide customers with a fair and exciting gaming experience. Customers enjoying the excitement that Laser Roulette provides may stay longer at the Roulette table thereby possibly earning more winnings for themselves or the casino. Laser Roulette will provide a more positive effect on the way Roulette is played for many years to come.
While there is shown and described herein certain specific structure embodying this invention, it will be manifest to those skilled in the art that various modifications and rearrangements of the parts may be made without departing from the spirit and scope of the underlying inventive concept and that the same is not limited to the particular forms herein shown and described except insofar as indicated by the scope of the appended claims. | A gaming system for games, including roulette, wherein a projection system, preferably with a laser, is utilized for illuminating selected areas of the roulette game table in order to highlight the winning bets, enhance security, provide for a consistent signal for closing of the betting period, provide advertising, and/or display messages at selected time during or between play of the game determined by sensing the motion of the wheel and/or ball and table activity. | 6 |
BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to buffered bile acid compositions for ingestion by a mammal, a process for preparing said compositions, and a method for treating digestive disorders, impaired liver function, autoimmune diseases of the liver and biliary tract, prevention of colon cancer following cholecystectomy, cystic fibrosis and for dissolving gallstones by administering said compositions to a mammal in need of such treatment.
Reported Developments
It is known in the prior art that ursodeoxycholic acid (hereinafter UDCA or bile acid) administered to mammals can remedy UDCA deficiency caused by various diseased conditions of the liver, such as gallstones, liver toxicity due to toxic metabolites, alcohol induced hang-over, drug related toxicity colon cancer following gallbladder surgery, and deficiency associated with poor digestion of fats and lipids in the intestine. UDCA requires the presence of certain conditions in order for it to be safe and effective as will be described hereunder.
UDCA and other bile salts are produced by the patient's liver, stored in the gallbladder and released into the duodenum in response to a meal, the pH of which is close to neutral or slightly alkaline. Under these basic pH conditions UDCA is soluble and biologically active and digestion of the food by UDCA proceeds normally in the upper segment of the intestine. However, when UDCA is administered exogenously to the patient, the gastric conditions in the stomach, namely the presence of acid, will render the UDCA insoluble. The insoluble UDCA is biologically inactive. Therefore, orally administered UDCA must be protected against gastric inactivation so that it remains intact during its transit through the stomach into the duodenum.
Once the exogenously introduced UDCA reaches the duodenum, another requirement must be satisfied: the UDCA must be released from its protective environment and intimately mixed with the food transferred from the stomach to effect digestion.
U.S. Pat. No. 4,079,125, incorporated herein by reference, addresses these requirements in a composition containing pancreatic enzymes, which closely approximate the behavior of UDCA in the acidic environment of the stomach and in the neutral-to-basic environment of the upper intestine, and provides preparative methods for making the compositions. The compositions provided by said patent comprise: an enzyme concentrate formulated with a binder/disintegrant and is coated with a non-porous, pharmaceutically acceptable enteric coating polymer which is insoluble in the pH range of from about 1.5 to about 5 normally present in gastric fluids, and soluble at a pH of from about 6 to about 9, the normal pH range for mammalian intestinal fluids. The orally administered composition passes through the stomach while being protected against the acidic environment by its acid-insoluble coating which then disintegrates in the neutral to basic environment of the upper intestine releasing the enzymes from the composition. The process of making the compositions includes the provision of using a solvent and avoiding the presence of water in the blending step of the enzyme/binder/disintegrant, since it is believed that water deactivates some of the enzymes.
It is known that ursodeoxycholic acid is capable of augmenting liver function, dissolving gallstones and improving the nutritional state of patients having cystic fibrosis caused by hepatobiliary complications. (See for example: Ursodeoxycholic acid dissolution of gallstones in cystic fibrosis. Sahl, B., Howat, J., Webb, K., Thorax, 43:490-1 (1988); Effects of Ursodeoxycholic Acid Therapy for Liver Disease Associated with Cystic Fibrosis. Colombo, C., Setchell, K. D., Podda, M., Crosignani, A., Roda A., Curcio, L., Ronchi, M. and Giunta, A., The Journal of Pediatrics, 117:482-489 (1990); Effects of Ursodeoxycholic Acid Treatment of Nutrition and Liver Function in Patients with Cystic Fibrosis and Longstanding Cholestasis. Cotting, J., Lentze, M. J. and Reichen, J., Gut 31:918-921 (1990). Also, UDCA has recently gained acceptance as an effective therapeutic modality to dissolve small to medium size cholesterol gallstones in gallstone afficted patients. (See for example: The Effect of High and Low Doses of Ursodeoxycholic Acid on Gallstone Dissolution in Humans, Salen, G., Colalillo, A., Verga, D., Bagan, E., Tint, G. S. and Shefer, S., Gastro., 78:1412-1418 (1980); Ursodeoxycholic Acid: A Clinical Trial of a Safe and Effective Agent for Dissolving Cholesterol Gallstones, Tint, G. S., Salen, G., Colalillo, A., Graber, D., Verga, D. Speck, J. and Shefer, S., Annals of Internal Medicine, 91:1007-1018 (1986); Clinical Perspective on the Treatment of Gallstones with Ursodeoxycholic Acid, Salen, G., J. Clin. Gastroenterology, 10 (Suppl. 2):S12-17 (1988); Nonsurgical Treatment of Gallstones, Salen, G. and Tint, G. S., New England J. Med., 320:665-66 (1989); and Reducing Cholesterol Levels, A. H. Weigand, U.S. Pat. No. 3,859,437. The recommended dosage is 10 to 15 mg/kg of body weight. In some patients much higher dosages (for example, about 30 mg/kg of body weight) are required to achieve limited benefits. However, in some patients undesirable side effects (such as severe diarrhea) seriously limit the use of this drug. The reasons for this wide variation of dosage requirements for therapeutic effectiveness and associated side effects are not completely understood. One hypothesis is that the acidic form of UDCA is only partially neutralized in the upper intestine to its sodium salt form. Many patients, such as patients with cystic fibrosis, pancreatitis or Billroth I & II and many elderly are deficient in bicarbonate secretion and lack neutralization capacity. These patients will only partially benefit from UDCA therapy. The insoluble acidic form of UDCA is poorly absorbed from the intestine, and a good portion of the administered dosage is excreted intact with feces. When a higher dosage of the acidic form of UDCA is administered to the patient, a large portion of it is neutralized in the distal parts of the intestine which in turn induces diarrhea, a highly undesirable side effect. Also, if the acidic form of UDCA is to be converted into its salt form in the duodenum, it will temporarily exhaust the buffering capacity of the duodenum and it will render the upper intestine partially acidic. The acidic pH impedes the function of the pancreatic enzymes and UDCA cannot emulsify fats and facilitate the hydrolysis of lipids. Furthermore, the many therapeutic benefits derived from the salt forms of UDCA cannot be realized. Accordingly, the salt forms of UDCA should be administered to patients in need of UDCA, since only the ionized, i.e. salt form of UDCA possess the desirable biological characteristics in the upper intestine, including the following: 1) is readily absorbed from the intestine; 2) inhibits cholecystokinin release by the intestinal mucosa, thus ameliorating pain and producing symptomatic relief; 3) enhances the flow of bile which cleanses the liver cells from accumulated toxic metabolites and thus reduces liver toxicity and autoimmune diseases of the liver and biliary tract; 4) prevents the binding and absorption of deoxycholic acid in the colon, thus prevents colon cancer development; 5) prevents the crystallization of cholesterol into gallstones; 6) emulsifies fats; and 7) facilitates the hydrolysis of fat globules. U.S. Pat. No. 3,859,437 recommends the administration of a "small but effective amount sufficient to effect a reduction in the cholesterol level of said human being, of the compound 3α, 7β-dihydroxy-5β-cholanic acid (UDCA) and the non-toxic pharmaceutically acceptable salts thereof". However, administering the salt form of UDCA to patients has no advantage over the acidic form of UDCA and does not accomplish the desired result since the salt form of UDCA is converted back to the acidic form of UDCA by gastric acidity. Furthermore, the salt forms, i.e., sodium or potassium, of UDCA are extremely bitter-tasting, and in most patients cause esophageal reflux, nausea and vomiting. Because of these highly undesirable organoleptic and gastric side effects, the salt forms of UDCA have not gained therapeutic utility in the treatment of biliary diseases.
It has now been discovered that the problems associated with tablets and capsules containing UDCA may be overcome in a composition containing buffered-UDCA instead of the acidic form of UDCA. In accordance with the discovery, UDCA is first buffered, processed into microspheres, and then coated with an acid-resistant polymer coating. Such composition overcomes the herein-described problems: 1) the polymer coating protects the buffered-UDCA from gastric acidity and neutralization of the buffer by the gastric acid; and 2) once the microspheres pass through the stomach in the duodenum, the protective coating dissolves in the neutral-to-alkaline range of the upper intestine. The microspheres disintegrate and release the buffered-UDCA into the intestine within ten to thirty minutes. Once the buffered-UDCA is released from the microspheres, the UDCA is rapidly neutralized to its soluble salt form and the composition also provides extra buffering capacity to neutralize the acid chyme.
It has also been discovered that the buffered-UDCA composition can be prepared into microtablets and microspheres in the presence of moisture without inactivation of the bile acid composition thereby resulting in products that do not crumble upon drying or disintegrate upon initiation of the polymer coating procedure. This discovery is contrary to the teaching of the aforementioned U.S. Pat. No. 4,079,125 which requires complete exclusion of water (anhydrous condition) during the process of preparing pancreatic enzyme-containing microtablets and microspheres. It was found that anhydrous conditions leads to products that are extremely friable, tend to crumble into pieces upon drying in a fluidized bed dryer or a conventional coating pan and disintegrate upon initiation of the polymer coating step. This results in large amounts of dust and agglomeration of the beads into multiplets during the process as well as improper doses of buffered-UDCA upon administration to the patient when quality control fails adequately to sort-out and discard said rejects. The bitter taste and associated gastric disadvantages of UDCA are also eliminated by the polymer coating which prevents solubilization of the product in the mouth and stomach of the patient.
Still further, it has been discovered that microspheres in the range of 10 to 40 mesh size can be prepared utilizing buffered-UDCA as seeds to build up the microspheres. Such small particle size microspheres are especially beneficial for treating bile acid deficiencies in cystic fibrosis children.
SUMMARY OF THE INVENTION
This invention will be described with particular reference to ursodeoxycholic acid, however, it is to be understood that other bile acids may be used as well.
In accordance with one aspect of the invention, there is provided a microencapsulated, polymer-coated composition comprising buffered-UDCA in a novel pharmaceutical dosage form. In another aspect, the invention provides a process for preparing buffered-UDCA for use in said composition. In still another aspect, the invention provides a process for the preparation of gastric acid-resistant polymer-coated buffered-UDCA-containing microspheres and microtablets. In its final aspect the invention provides a method for treating bile acid deficiencies associated with biliary diseases in mammals, such as gallstones, liver toxicity due to toxic metabolites and autoimmune diseases of the liver and biliary tract, alcohol induced hang-over, drug related toxicity prevention of colon cancer following cholecystectomy, and deficiency associated with poor digestion of fats and lipids in the intestines.
Preparation of Buffered UDCA Microspheres and Microtablets
Recognizing the above limitations of UDCA it has now been discovered that by micropulverizing the UDCA in the presence of a suitable buffer salt one can obtain ultrafine particles of the buffered-UDCA that will readily dissolve in the intestinal juices under physiological conditions. The micropulverized and buffered-UDCA is physically converted into microspheres of 10 to 40 mesh size by a process of granulation with suitable solvents and polymeric binders, extruded into segments of 0.2 to 0.5 mm and rounded into spherical particles. The microspheres are coated with a gastric acid impermeable polymer coating that protects the buffered-UDCA from gastric acidity during gastric transit and releasing the buffered-UDCA in the duodenum under neutral condition. Once the buffered-UDCA is released from the microspheres into the upper intestine it is instantly converted to the Na-UDCA in situ. With the delivery of buffered-UDCA into the duodenum in its biologically active state, one can achieve hitherto unrealized benefits of Na-UDCA over the insoluble and poorly absorbed acidic form of UDCA.
As previously indicated, only the salts of UDCA are absorbed from the intestine, while the acidic form of UDCA is passed through the intestine intact, unless it is converted to the sodium salt by intestinal buffers. However, many patients, such as patients with cystic fibrosis, pancreatitis, Billroth I and II diseases and some elderly people, are deficient in bicarbonate secretion and lack neutralization capacity to convert the acidic form of UDCA to the sodium salt of UDCA. These patients will only partially benefit from the insoluble acidic form of UDCA therapy. The buffered-UDCA-containing composition of the present invention overcomes this problem by the buffer converting the UDCA into Na-UDCA in situ. Additionally, the composition also provides extra buffering capacity to neutralize the acid chyme that is present in the intestine.
The buffered-UDCA composition is microencapsulated and coated with an acid resistant polymer coating, which protects the composition from gastric acid. The polymer-coated microcapsules are tasteless and the problem associated with the offensive bitter taste of the uncoated acidic form or the uncoated salts of UDCA is thereby alleviated.
The microcapsules uniformly disperse with the food in the stomach and deliver high levels of biologically active UDCA into the duodenum. Once in the duodenum, the polymer coating dissolves within about 10 to 30 minutes and the buffered-UDCA is released to be converted into the soluble salt of UDCA in situ. The soluble and biologically active UDCA enhance digestion of fats and lipids. As a result, the natural digestive conditions in the intestine are reestablished. Epigastric pain, cramps, bloating, flatulance and stool frequency associated with maldigestion of fatty foods are reduced.
Soluble salts of UDCA formed by the presence of a buffer are absorbed more efficiently and in a greater quantity from the intestine than the insoluble acidic form of UDCA, resulting in a more efficient stimulation of the liver enzymes to conjugate ursodiol (UDCA). The increased concentration of the conjugated ursodiol stimulates bile flow, enhances the displacement of toxic bile acid metabolites from the hepatocytes, decreases cholesterol secretion into bile, alters the cholesterol/phospholipid ratio of secreted bile and decreases the absorption of dietary biliary cholesterol from the intestine. The overall result is decreased biliary cholesterol saturation, increased bile flow, dissolution of already formed cholesterol gallstones and protection of the liver from accumulated toxic metabolites.
Compositions of Buffered-UDCA
The composition containing buffered-UDCA comprises a blend of ingredients and a coating therefor expressed in weight per weight percentages based on the total weight of the composition:
a) from about 60 to about 89% of a buffered-UDCA mixture in a 1 to 1 neutralization equivalent ratio in a micropulverized powder form;
b) up to about 5% of an additional buffering agent selected from the group consisting of about 0.25 to about 5.0% sodium carbonate (anhydrous powder), sodium bicarbonate, potassium carbonate and potassium bicarbonate and from about 0.25 to about 1.5% tromethamine, diethanolamine and triethanolamine;
c) from about 1.0 to about 16% of a disintegrant selected from the group consisting of starch and modified starches, microcrystalline cellulose and propylene glycol alginate;
d) from about 2.0 to about 19% of an adhesive polymer selected from the group consisting of polyvinylpyrrolidone, hydroxypropyl cellulose, cellulose acetate phthalate, methyl cellulose and propylene glycol alginate; and
e) from about 8.0 to about 16% of a non-porous, pharmaceutically acceptable gastric acid-resistant polymer-coating which contains less than 2% talc and which is insoluble in the pH range of from about 1.5 to about 5 but is soluble in the pH range of from about 5.5 to about 9.
The Process of Making the Microsphere
In accordance with the present invention, the buffered-bile acid composition is prepared by a process comprising the steps of:
a) blending dry, micropulverized powdery ingredients selected from the group consisting of (i) from about 60 to about 89% w/w of a buffered/bile acid in a 1 to 1 neutralization equivalent ratio; (ii) up to 5% of an additional buffering agent selected from the group consisting of from about 0.25 to about 5.0% w/w sodium carbonate (anhydrous), sodium bicarbonate, potassium carbonate and potassium bicarbonate and from about 0.25 to about 1.5% w/w tromethamine, diethanolamine and triethanolamine; (iii) of from about 1.0 to about 16% w/w a disintegrant selected from the group consisting of starch and modified starches, microcrystalline cellulose and propylene glycol alginate; and (iv) from about 2.0% to about 19% w/w of an adhesive polymer selected from the group consisting of polyvinylpyrrolidone, cellulose acetate phthalate, hydroxypropyl cellulose, methylcellulose and propylene glycol alginate;
b) wetting said blended ingredients with a liquid to cause the blend to stick together, wherein said liquid is selected from the group consisting of: 1%-25% w/w ethanol/75%-99% w/w 2-propanol/0.2%-2% w/w water; 98%-99% w/w 2-propanol/0.2%-2% w/w water; 1%-25% w/w methanol/0.2%-2% w/w water/75%-98% w/w 2 propanol/1%-5% w/w ethylacetate;
c) granulating or extruding the liquid-wetted blend through a 10 to 18 mesh S/S screen;
d) converting the granules to a uniform diameter particle size;
e) compacting the uniform particles to spherical particles;
f) drying the spherical particles;
g) separating the spherical particles if not of uniform size according to desired sizes using U.S. Standard sieve screens;
h) coating the particles with a gastric acid-resistant polymer that dissolves under neutral or slightly basic conditions; and
i) drying the polymer-coated spherical particles.
DETAILED DESCRIPTION OF THE INVENTION
In preparing the buffer-UDCA containing microspheres of the present invention utilizing the extrusion, uni-sizer and marumerization process (later described) moisture must be included in the liquid or solvent-adhesive composition to render the adhesive polymer sticky enough to bind the buffered-UDCA containing micropulverized fluffy powder into a pliable, solid mass. This prevents the crumbling of the microspheres during the drying and coating process as well as allows the preparation of much smaller particle size microspheres, i.e. in the range of 10 to 80 mesh. Accordingly, it was found that the moisture level during the preparation of the composition should be in the range of from about 0.2% w/w to about 2.5% w/w, preferably, in the range of 0.2% w/w to 1.5% w/w, and most preferably in the range of 0.2% w/w to 1.0% w/w. When the compositions contained such amounts of moisture, the microspheres were found to be stable on aging and the integrity of the microsphere was preserved.
Further reference is now made to the process of preparing compositions of the present invention.
The process of manufacturing the microspheres comprises the following steps:
a) The dry, micropulverized powdery ingredients are blended together in a conventional blender.
b) The blend is then wetted with a suitable liquid, hereinbefore described, that causes the dry blend to stick together. The stickiness of the blend can be tested by compressing a handful of the blend in the palm of the hand. If the composition is compressible and sticks together, but readily crumbles when squeezed between the fingers, sufficient liquid has been added to the composition for processing in the subsequent granulation step.
c) The blend is granulated or extruded though a 10 to 18 mesh S/S screen using an oscillating/reciprocating granulator or a twin-screw extruder at a medium-to-high speed.
d) The granulated particles are classified in a so-called uni-sizer vessel that rotates at 15 to 45 rpm for about 5 to 10 minutes. The particles in this vessel are converted to a uniform diameter particle size.
e) The uniform particles are then compacted in a marumerizer, which is essentially a cylindrical vessel with a rotating disk at the bottom thereof, for about 15 to 90 seconds. An alternative method of compacting the microspheres can also be accomplished in a rotating conventional coating pan. In this case, the particles are tumbled in the pan for about 15 to 30 minutes, with occasionally wetting the particles with a fine mist of the liquid composition (described in (b) under the Summaey of the Invention)
f) The spherical particles are dried in an oven under a stream of dry air not exceeding 35° C. and 40% relative humidity.
g) The microspheres are separated according to the desired sizes using U.S. Standard sieve screens.
h) The microspheres having 10 to 20 and 30 to 40 mesh size are separately coated with an acid-resistant polymer in a fluidized bed coating equipment, or in a conventional coating pan according to standard operating procedures as described in the manufacturer's instruction manual.
i) The polymer-coated microspheres are then dried in an oven under a stream of warm and dry air, not exceeding 35° C. and 40% relative humidity until all the volatile substances (moisture and solvents) are removed.
The following examples will further serve to illustrate the compositions of the present invention wherein the compositions and the process of preparing them will be described with reference to microsphere forms; however, it is to be noted that the microtablet form of the composition and the process of making it is also intended to be covered by the present invention. The process of making the microtablet form of the composition is analogous to that of making the microspheres with the exception that the 20 to 80 mesh particles are compressed together into microtablets of 0.5 mm to 2.5 mm with a suitable tablet press and polymer coated, and should be understood by those skilled in the art.
EXAMPLE I
Formula Composition (microspheres)
______________________________________ A (uncoated) B (coated)Ingredients % w/w % w/w______________________________________Disintegrant 6.0 5.2Buffered-UDCA (micronized) 89.0 76.7Buffering agent (anhydrous) 2.0 1.7Adhesive Polymer 3.0 2.6Polymer coat/talc mixture 13.8______________________________________
EXAMPLE II
Formula Composition (microspheres)
______________________________________ A (uncoated) B (coated)Ingredients % w/w % w/w______________________________________Disintegrant 9.0 7.6Buffered-UDCA (micronized) 82.0 69.5Buffering agent (anhydrous) 1.0 0.8Adhesive Polymer 8.0 6.8Polymer coat/talc mixture 15.3______________________________________
EXAMPLE III
Formula Composition (microtablets)
______________________________________ A (uncoated) B (coated)Ingredients % w/w % w/w______________________________________Disintegrant 3.0 2.7Buffered-UDCA (micronized) 89.0 82.1Buffering agent (anhydrous) 1.0 0.9Adhesive Polymer 3.0 2.7Lubricant (stearic acid) 1.0 0.9Polymer coat/talc mixture 10.7______________________________________
The microtablets are prepared by the following procedure: 1) grinding the dry blend of buffered-UDCA/buffer/disintegrant in a centrifugal mill or impact pulverizer to a uniform particle size; 2) spraying the powdery mix with a fine mist of the adhesive polymer/liquid mixture; 3) and drying the composition, followed by blending the dried composition with a lubricant and compressing the free flowing powder into microtablets of 1.5 mm×2.0 mm with appropriate punches and dies and using a tableting press as described in U.S. Pat. No. 4,828,843 (Pich et al.) which is hereby incorporated by reference. The microtablets are polymer-coated with a gastric acid-resistant polymer as described above in The Process of Making the Microspheres.
EXAMPLE IV
Formula Composition (polymer coated microspheres)
______________________________________Ingredients % w/w______________________________________Buffered-UDCA starting seed (20-40 mesh) 12.8Disintegrant 2.3Buffering agent (anhydrous) 1.1Buffered-UDCA (micronized) 69.0Adhesive polymer mixture 4.1Polymer coat/talc mixture 10.7______________________________________
The microspheres of Example IV were prepared by employing a conventional coating pan. The microspheres were built up to larger particle sizes by placing the buffered-UDCA containing 30 to 40 mesh starting seeds in the rotating coating pan, wetting the microspheres with the liquid/adhesive polymer-containing mixture, followed by slowly dusting the buffered UDCA/buffer/disintegrant composition over the tumbling and flowing buffered-UDCA containing seeds. The sequence of these steps is repeated until the seeds are built up into microspheres having diameters in the range of 10 to 20 mesh, preferably 14 to 16 mesh.
An alternate procedure for the preparation of the microspheres in Example IV was carried out in fluidized bed coating equipment (Glatt Mfg. Co.) using a Wurster column. The starting seeds were placed in the equipment and fluidization was started. The buffered-UDCA/disintegrant/buffer/adhesive polymer mixture was sprayed on the fluidized microspheres as a homogeneous mixture at a rate that allowed the growth of the starting seeds to larger microspheres.
EXAMPLE V
Preparation of Buffered-UDCA Containing Starting Seeds
______________________________________Ingredients % w/w______________________________________Buffered-UDCA (micronized) 60.7Disintegrant 16.0Buffering agent (anhydrous) 4.6Adhesive polymer 18.7______________________________________
The process of making the buffered-UDCA containing starting seeds consisted of: 1) micropulverizing the buffered-UDCA blend in a centrifugal grinder or an impact pulverizer and blending the resultant buffered-UDCA, disintegrant and the buffering agent together for 10 minutes; 2) spraying the composition with the adhesive polymer mixture until the powdery blend agglomerated; and 3) granulating or extruding the liquid moistened composition through a 10 to 18 mesh S/S screen using an oscillating/reciprocating granulator or a twin-screw extruder. The subsequent processing steps were the same as outlined in Steps a through g in "The Process of Making the Microspheres" under Summary of the Invention.
Reference is now made to the ingredients used in the above examples:
Bile Acids: ursodeoxycholic acid, glycyl and tauroursodeoxycholic acids.
Disintegrant: Explotab (Mendell, Inc.) and microcrystalline cellulose.
Buffering agents: from about 0.25% to about 5.0% w/w %, sodium carbonate (anhydrous), sodium bicarbonate, potassium carbonate, potassium bicarbonate and based on the total weight of the composition; from about 0.25% to about 1.5% w/w % tromethamine, diethanolamine and triethanolamine based on the total weight of the composition.
Adhesive Polymeric Agents: Hydroxypropyl cellulose (Klucel HF, Hercules Co.), poly-vinyl pyrrolidone (Plasdone, GAF Co.), a 60:40 blend of methyl cellulose and ethyl cellulose (Dow Chem. Co.), hydroxypropyl methyl cellulose (Grades 50 and 55, Eastman Kodak Co.), cellulose acetate phthalate (Eastman Kodak Co.) and propylene glycol alginate (Kelco Co.).
Acid-resistant polymers to coat the microspheres and microtablets: hydroxypropyl methyl cellulose phthalate, Grades 50 and 55 (Eastman Kodak Co., or Shin-Etsu Chemical Co., Ltd.), Aquateric® aqueous enteric coating polymer dispersion (FMC Corp.), Eudragit® acrylic based polymeric dispersion (Rohm Pharma GMBH, Germany), and cellulose acetate phthalate (Eastman Kodak Co.). The following example will further illustrate the composition of the acid-resistant polymer-coatings:
EXAMPLE VI
______________________________________ % w/w______________________________________Cellulose acetate phthalate (CAP)* 7.5Diethyl phthalate (DEP) 2.0Isopropyl alcohol (IPA) 45.0Ethylacetate (EtoAc) 45.0Talc, USP 0.5______________________________________ *When the hydroxypropyl methyl cellulose phthalate was replaced with cellulose acetate phthalate, an equally suitable acidresistant polymercoating was obtained, as long as talc was also included in the composition. The presence of talc with the film forming polymer caused th deposition of an acidimpermeable polymer coat. When Aquateric ® or Eudragit ® aqueous enteric coating polymer dispersion was employed in place of hydroxypropyl methyl cellulose phthalate (HPMCP ), the microspheres were first sealed with a thin layer coat of the HPMCP (2-4% w/w of the microspheres) followed by coating with the Aquateric ® or Eudragit ®. The advantage of using an aqueous based polymeric dispersion is to saave on solvents that are evaporated during the solvent based coating step and cust down on environmental pollution.
Distribution of microspheres according to sizes is shown in Table I.
TABLE I______________________________________Distribution of the Microspheres According to Sizes Example IB Example IIBMesh Size (mm) Microspheres (%) Microspheres (%)______________________________________10 2.00 6.2 3.314 30.0 57.020 0.84 53.8 32.740 0.42 10.0 7.0______________________________________
Method of Treating UDCA Deficiency
The composition of the present invention are orally administerable to patients having UDCA deficiency in an effective amount to treat such deficiency. The compositions are tasteless unlike the insoluble acidic form of UDCA administered per se which is associated with an offensive bitter taste. This advantage increases patient compliance in taking the medication. The microspheres are administerable admixed with food or they may be filled into gelatin capsules for administration in a conventional manner. In both methods of administration the microcapsules pass through the stomach intact, being protected by their acid-resistant coating. While in the stomach, the microcapsules uniformly disperse with the food therein and pass into the duodenum to deliver high levels of biologically active UDCA. In the duodenum the polymer coating dissolves within ten to thirty minutes and the UDCA is released.
The total amount of the composition required to be administered to a bile acid deficient patient will vary with the severity of the conditions, age and other physical characteristics of the patent. Physicians will prescribe the total amount, the dosage, the frequency of administration on a patient by patient basis. Generally, for bile acid deficient patients, from about 0.15 to about 0.75 grams of the composition are administered once or twice a day. Larger amount may, however, be required for certain conditions, such as for dissolving gallstones.
For ease of administration of the compositions it is preferred to use gelatin capsules containing about 0.25 to 0.4 grams microspheres or microtablets. Gelatin capsules which disintegrate in the acidic environment of the stomach are well-known and utilized in the prior art. Microtablets are of small size, having a diameter between about 1 to 5 mm and a thickness between 0.5 to 4 mm. The tablet is prepared by conventional tableting procedure. However, the compositions of the present invention in the form of very small particle sizes may be used per se. For example, young children, handicapped individuals with certain diseases and elderly patients are unable to swallow big gelatin capsules. Microspheres of very small size of the present invention could then be administered to these patients with liquid food, such as milk, apple sauce and semi-solid foods.
The advantages of the polymer-coated microspheres and microtablets over capsules and large tablets are well recognized in the administration of therapeutic medications. The microspheres and mini tablets disperse uniformly with the food in the stomach due to the smaller particle size of these particles and are more uniformly coated with the polymer-coating because of their spherical shape. They also release their UDCA content more readily than compressed large tablets or capsules. The microspheres are protected from gastric acidity by the acid-resistant polymer-coating during gastric transit. Once the microspheres reach the duodenum, the polymer-coating dissolves under neutral-to-slightly-alkaline conditions and the microspheres discharge their buffered-UDCA content in the upper intestine within minutes. The micropulverized UDCA is instantly neutralized by the provided buffer and converted to the Na-UDCA in situ. This release and instant neutralization of UDCA to its ionized form (Na-UDCA) results in an efficient emulsification of fats and lipids, digestion of the emulsified lipids by pancreatic lipase, liquefaction of mucus that obstructs the intestinal mucosa and acceleration of the enzymatic digestion of mucopolysaccharides. As a result of this synergetic interaction between bile salts and pancreatic enzymes, mucus is lysed, and the receptor sites on the intestinal villi are exposed to the outer environment. The unblocked receptors can bind essential metabolites and transport them through the intestinal membrane into portal circulation. The net result is the normalization of the intestinal digestive function, enhanced absorption of the liberated metabolites and the amelioration of the dyspeptic symptoms associated with the upper gastrointestinal tract. | Disclosed are gastric acid-resistant polymer-coated buffered-bile acid compositions, process for their preparations and methods of treating digestive disorders, impaired liver function, autoimmune diseases of the liver and biliary tract, prevention of colon cancer following cholecystectomy, cystic fibrosis, dissolving gallstones and regulating dietary cholesterol absorption by administering said compositions to a mammal in need of such treatment. | 8 |
SUMMARY OF INVENTION
In the preservation and restoration of organic material containing art objects a number of expedients are already well known.
For example, it is well known to neutralize acid traces in drawings on paper by immersing the drawings in a weak magnesium carbonate solution saturated with carbon dioxide, and then carefully drying the drawings. Such treatment will neutralize acid present in the paper and will largely guard against future deterioriation.
However, when deterioration has already occurred, the restorer faces difficulties. Even if the further acid hydrolysis of the cellulose and if the external appearance of art object is restored to its original state, the internal strength of the material may be so damaged as to prevent exhibition. For example, a textile hanging could be restored by reweaving small portions thereof with the same type of threads and yarns, in the same size, color, texture and touch as used in the original, but te restored hanging might have too little internal strength to permit it to be hung for an exhibition.
It is an object of the instant invention to strengthen organic material containing art objects by incorporating into the material of the object a small amount of an unsaturated resin, which is polymerized in situ by irradiation with large amounts of ionizing radiation, such as x-rays, gamma rays, beta rays or high speed electrons from an electron accelerator. No catalyst or accelerator is utilized to accomplish the polymerization, and therefore damage to the art object by highly reactive catylists or accelerators, such as organic peroxides, is avoided. The ionizing radiation not only polymerizes the unsaturated resin, but also sterilizes the art object by killing any living worms, insects eggs, molds, mildew, fungi, spores, or other biological vectors.
The nature of the resin utilized in the practice of the invention depends upon the nature of the organic material containing art object.
If the art object is a tapestry or dress which should have some degree of flexibility, so that it can drape naturally, a low impregnation with an unsaturated silicone resin can be used. The cured resin is very pliable and, because of both the pliability and the low amount of impregnation, the feel or hand of the fabric is not materially changed. The low impregnation, however, strengthens and consolidates the fibers.
If the art object is a painting on canvas, where the painting itself is stiff and not subject to folding and draping, a styrene/unsaturated polyester resin or a methyl methacrylate monomer can be used. The cured resin has a stiffness appropriate to that of the art object.
In the case of art objects made of cellulose materials, such as etchings, points and delicate wood carvings, the resin can be a polyester resin, in which case a graft polymerization between the cellulose and the copolyester resin takes place, producing a molecular bond between the cellulose and the resin.
The kind of radiation utilized to produce the polymerization depends on the nature of the art object.
If the art object is three dimensional, a source of penetrating radiation can be used, as this ensures that the interior of the object will get sufficient exposure. Such radiation is most conveniently supplied by a gamma ray source such as a Cobolt 60 source (the most common type) or other radioactive isotope source, or from an industrial X-ray generator.
If the art object has little depth in one direction, as in the case of a flat painting on canvas, a source of lesser penetration can be used. Such a source would be a radioactive beta emitter or an electron accelerator biased by a high voltage source such as a Van der Graff generator.
From the foregoing, it is evident that the resin used in the new process is utilized as a binding agent to consolidate the material of the object into a stronger structure. The binding may be within a single substance, such as a sheet of paper, or it can be between different substances, such as flakes of paint and the wood panel substrate from which they have loosened.
DETAILED DESCRIPTION
Three embodiments of the invention in practice will now be described under headings set forth below.
TAPESTRY
The tapestry is first restored to its original state as much as possible by utilizing a skilled rug restorer to replace a reweave any missing portions of the tapestry, utilizing threads and yarns which duplicate the original in all pertinant characteristics. These characteristics include color, size, material, twist and lay of the threads and the yarns. Many of the threads and yarns will have to be made up from raw materials and natural dyes for the specific repair. It is noted that skilled artisans, who restore burns and tears in expensive clothing and rugs, can be located in the classified telephone directories under a heading such as "Weaving and Mending" and "Carpet and Rug Reweaving". Such artisans have the necessary skills, qualifying them to work on the analogous task of restoring a damaged, precious tapestry, under the direction of a conservator.
The tapestry is then carefully cleaned by use of a mild solvent, such as a highly purified straight chain paraffinic oil which is chemically neutral, which will completely evaporate at temperatures which will not injure the tapestry, and which will not break down or react to form deleterious products. Chlorinated dry cleaning solvents should be avoided because of the chlorine content and ordinary Stoddard dry cleaning solvent should be avoided because it does not completely evaporate at room temperatures.
If the tapestry will be hung in a public hall, it must be protected from moths, and a suitable mothproofing can be given as part of the cleaning operation. A prefered treatment is with "Eulan CN", which is an anionic agent containing, as the active ingredient, sodium pentachlorodihydroxytriphenyl methane sulfonate. This treatment provides a permanent mothproofing and is compatible with natural fibers, natural dyes, acid or chrome dyes and with anionic and non-ionic surfactants. Although this treatment is not compatible with basic dyes, cationic surfactants or albumin based sizes and leveling agents, these last named items are infrequent and are not found in antique tapestries.
The cleaned and repaired tapestry is then subjected to a low impregnation of a highly purified unsaturated silicone resin. It is prefered to utilize a grade of silicone resin which is government-approved for the making of items in contact with food or living tissue, such as the flexible tubing used in liquid food packaging equipment of surgical implants.
The resin is applied in a measured and uniformly distributed manner to the tapestry, preferably by being applied in separate measured amounts to separately measured sub-areas of the tapestry, either by careful brushing or by a spray technique.
The tapestry is permitted to be at rest for a time, during which the resin migrates to produce a uniform impregnation. It has been found that if the tapestry is subjected to a rough vacuum, such as that provided by a Boekel water aspirator or a mechanical fore pump, either immediately before or during the impregnation, that the resin is absorbed more rapidly and uniformly.
Once impregnated, the resin is polymerized in situ by application of ionizing radiation. The total exposure to radiation is adjusted to about 5000000 RAD, and is supplied by a radioisotope. A convenient isotope to use a Cobalt 60 , since the isotope is in regular use for industrial X-raying of heavy metal welds, so that, for a single use, it is both possible and cheaper to rent the source rather than to purchase it. If a source is to be purchased, another isotope, of lesser penetrating power, and possibly shorter half life, might be preferable, as determined by factors such as the cost of the isotope needed to give the required exposure within an economical period, and the expected length of use of the isotope before it is returned for burial.
The polymerized silicone resin acts to consolidate and bind together the fibers of the tapestry with a soft and yielding bond. It is important that the resin have a considerably lower Young's modulous than do the fibers of the tapestry. Thus, when the fabric is handled, the fibers are not subject to a point like concentration of stress, but, instead, the stress is distributed across the entire extent of the fiber-resin interface. This avoids the problems which would be met with a strong rigid adhesive, which would split and render appart the weaker fibers.
If the tapestry is so weakened that it is apt to break from handling, despite the impregnation, it can be supported between two layers of undyed and unsized silk crepeline or organdy, stitched to each other, through the tapestry, with silk thread. The support thus provided is almost invisible. However, the support thusly provided is pointlike in nature, that only those points that which the two layers of silk are stitched to each other, thus creating points of increased stress on the weakened tapestry. It is therefore preferable to provide a more uniform support, by adhering the fabric of the tapestry to a backing of fiberglass cloth, utilizing a suitable adhesive of the type commonly used by conservators in museums. The adhesive can be a thermoplastic one based on beeswax, such as are routinely used to reline paintings on canvas, or it can be based on a synthetic resin.
OIL PAINTING ON CANVAS
The general procedure in treating an oil painting is analogous to that of the tapestry, described above. However, because the canvas on which an oil painting lies is almost pure cellulose, while tapestries usually have only a minor amount of cellulose, and because the canvas of oil paintings is, unlike a tapestry, not subject to much bending or folding, a different resin is used.
Initially the painting is cleaned and then restored at least in part. If there is a severe problem of exfoliation of the paint, it is advisable to reserve the restoration of the original appearance to the last.
The painting is then turned face down on a table, adapted for use as a vacuum table, onto a new sheet of parting material, such as Mylar film. It is advisable to wax the film before use with a tiny amount of hard wax which is then polished away with clean cloths, in the same manner that the professional photographer waxes and polishes his ferrotype tins. This will prevent any sticking of the fragile paint surface to the film on the table during subsequent treatment.
Any previously applied lingings at the back of the painting are then removed. In the case of some old paintings, linings have been added at various times so that in some instances the canvas layers are almost a centimeter thick.
The exposed original canvas is cleaned on its back face in preparation for application of the resin.
The resin used in this instance is a low impregnation of an unsaturated purified polyester resin. This resin has the property that when it polymerizes under the action of ionizing radiation, it will not only link up with itself but it will also graft-polymerize by linking polyester molecules to cellulose molecules. The resin is applied to the cleaned back face of the original canvas, and then polymerized, using the same technique as used with the tapestry.
The polyester resin can be assisted, in its migration within the oil paint layers and canvas of the painting, by pulling a vacuum on the table, before the ionized radiation is applied, holding the vacuum for a period, and then releasing the vacuum.
Before lifting the impregnated painting off the parting sheet, it is advisable in some instances to apply a supporting lining, utilizing standard museum techniques. The fact that the painting is on a vacuum table assists in the application of the lining.
After the painting is pulled off the parting sheet, the paint and original canvas are found to be consolidated and structurally stronger than before. The amount of polyester used is not sufficient to change the sheen of the painting surface.
Final restoration of the face of the painting to its original appearance, if necessary, is then made.
WOOD CARVING
A wood carving which has suffered insect and mold attack and contains some spongy and rotten parts presents problems because of the three-dimensional arrangement of differently affected parts.
After the surface of the carving has been restored to its original appearance as much as possible, the carving is impregnated with a mixture of styrene/unsaturated polyester resins, or a methyl-methacrylate monomer. A prefered way to do this is by immersion and vacuum impregnation. In the case of very large carvings, such as totem poles, vacuum impregnation may be impossible and injection of the resins through bored holes or brushing of the resin is used.
The excess resin is thereafter removed by careful wiping with cloths and repeated dusting with fine dry sawdust, so that the carving finally is returned to its just-previously restored appearance. That is, no excess resin produces any sheen of its own on the surface of the wood carving.
The wood carving, at this stage, is subject to ionizing radiation to polymerize the resin impregnation, thereby restoring strength and integrity to damaged areas. | A method for treatment of an organic material containing art object, such as a wood carving, a painting on wood or canvas, a textile hanging or a tooled leather saddle, for preservation and restoration thereof. The method includes the steps of partially impregnating the art object with an unsaturated resin and exposing the partially impregnated art object to a large dose of radiation to polymerize the resin, without addition of any catalysts and without the production of any significant exothermic reaction. The polymerized resin strengthens the art object and the radiation sterilizes the art object, destroying insects, molds, and other destructive biological vectors. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to a modifier for modifying the polyester fiber as well as preparation method and application of the same.
BACKGROUND OF THE INVENTION
[0002] It is well known that the polyester fiber is poor at hygroscopicity, antistatic property, decontaminating property, and bulky and soft property. The aminosilane emulsion is used as a main assistant in its after finish. However, the aminosilane emulsion can improve the polyester fiber in hand feeling rather than it's antistatic and anti-contaminating properties. Therefore, the current commercially available textile products made of the polyester fiber are poor at wearing, antistatic, and anti-contaminating properties, and may do certain harm to the human health.
SUMMARY OF THE INVENTION
[0003] A first purpose of the present invention is to provide a modifier for modifying the polyester fiber to make it healthy and comfortable.
[0004] The following technical solution is adopted in the present invention to achieve the above purpose: The modifier includes the following components based on parts by weight: 10˜25 parts of ethylene glycol, 15˜25 parts of dimethyl terephthalate, 1˜50 parts of two-polyether-end organosilicon, 0.2˜1 part of metal acetate as a catalyst, and 80˜170 parts of compounds selected from one, two or more kinds of two-hydroxy-end polyethers with a molecular weight of 1000˜20000 and a general formula of (I), (II) or (III);
[0000] H(OCH 2 CH 2 ) m OH (I);
[0000] H(OCH 2 CH(CH 3 )) n OH (II); and
[0000] H(OCH 2 CH 2 ) p (OCH 2 CH(CH 3 )) q OH (III);
[0005] where m, n, p and q stand for number of the repeating unit.
[0006] A second purpose of the present invention is to provide a method of preparing the modifier as described above.
[0007] The following technical solution including the following steps is adopted in the present invention to achieve the above purpose:
[0008] 1) Each of the components is weighed as required;
[0009] 2) glycol and the compounds selected from one, two or more kinds of two-hydroxy-end polyethers with a general formula of (I), (II) or (III) are added into a reactor, which is then heated; the reactor is vacuum-pumped when its temperature rises to 60˜80°, making vacuum degree inside the reactor up to −0.090˜0.095 Mpa; then the reactor is heated further to 80˜100° until the materials inside are dehydrated completely; air is introduced into the reactor, which is then heated to 100˜120°; dimethyl terephthalate, two-polyether-end organosilicon and the catalyst are added into the reactor, which is then heated further to 150˜190° to make the materials in the reactor completely esterificated;
[0010] 3) the materials completely esterificated in the reactor are added into a polymerizer; the materials are polymerized under −0.08˜−0.1 MPa vacuum degree and 200˜300° temperature conditions with the catalyst, producing a polyester/polyether/organosilicon terpolymer with a molecular weight of 1000˜50000; and then the polymerizer is cooled down to 100˜160° to discharge the materials, producing the modifier product as required.
[0011] A third purpose of the present invention is to provide some typical applications of the modifier in modification of the polyester fiber, so as to make the modified polyester fiber possess many good properties.
[0012] 1) Application as a bulking finishing agent: The bulking finishing agent contains 5˜10% (weight ratio) of the modifier and the remaining of water.
[0013] 2) Application as a smooth hydrophilic finishing agent: The smooth hydrophilic finishing agent contains 5˜10% (weight ratio) of the modifier and the remaining of water. It can make the modified polyester fiber not only bulky and soft, but also smooth and hydrophilic.
[0014] 3) Application as a durable antistatic agent: The durable antistatic agent contains 5˜10% (weight ratio) of the modifier, 20˜50% (weight ratio) of tertiary amine salt polymer, and the remaining of water. It can make the modified polyester fiber not only bulky and soft but also antistatic. The tertiary amine salt polymer is alkyl tertiary amine chloride or alkyl tertiary amine nitrate.
[0015] 4) Application as a decontaminating finishing agent: The decontaminating finishing agent contains 5˜10% (weight ratio) of the modifier, 2˜5% (weight ratio) of glycerin or ethylene glycol or fluororesin, and the remaining of water. It can make the modified polyester fiber not only bulky and soft but also more decontaminating.
[0016] 5) Application as a bath anti-creasing agent: The bath anti-creasing agent contains 5˜10% (weight ratio) of the modifier, 0.5˜3% (weight ratio) of polyacrylamide, and the remaining of water. It can make the modified polyester fiber not only bulky and soft but also anti-creasing.
[0017] 6) Application as a hydrophilic anti-creasing high-temperature levelling agent: The hydrophilic anti-creasing high-temperature levelling agent contains 3˜20% (weight ratio) of the modifier. It can make the modified polyester fiber not only bulky and soft but also higher in the dyeing quality.
[0018] 7) Application of the modifier in the dyeing process of the polyester fiber fabric. This application has the following features: The modifier and dyes as well as other assistants (e.g. levelling agent) are added together in the dyeing process at the dyeing temperature of 60˜130°, with weight of the modifier being 0.05˜5% of that of the fabric.
[0019] 8) Application of the modifier in the dipping process of the polyester fiber fabric. This application has the following features: The modifier is added into the dipping liquid in the dipping process, with weight of the modifier being 0.055% of that of the fabric.
[0020] 9) Application of the modifier in the padding process of the polyester fiber fabric. This application has the following features: The modifier is added into the padding tank in the padding process, with weight of the modifier being 0.05˜5% of that of the fabric.
[0021] The relevant contents in the above technical solutions are explained as below:
[0022] 1. In the above solutions, the two-polyether-end organosilicon is an organosilicon with the following general formula:
[0000]
[0023] where R 1 and R 2 respectively stand for an alkoxy with 1˜10 carbon atoms, and R 3 , R 4 , R 5 and R 6 for hydrogen, methyl, and ethyl, with the typical compounds shown as below:
[0000]
[0024] 2. In the above solutions, the reactor is heated. The reactor is vacuum-pumped when its temperature rises to 60˜80°, making vacuum degree inside the reactor up to −0.090˜−0.095 Mpa. Here the moisture has started to be evaporated. In order to make the moisture evaporated completely, the reactor needs to be heated further to 80˜100°. Then the discharge valve is opened to introduce air into the reactor.
[0025] 3. In the above solutions, the metal acetate catalyst includes zinc acetate, calcium acetate, magnesium acetate, and potassium acetate.
[0026] The present invention has the following beneficial effects: the modifier of the present invention can modify the polyester fiber, making the modified polyester fiber good at hand feeling (bulky, soft and smooth), antistatic property, decontaminating property, and washability, thus greatly improving comfortability of the fabric made of the modified polyester fiber. Besides, the present invention further discloses that various kinds of reinforced modifiers are prepared with the modifier as the mother liquid to further improve the effect of modifying the polyester fiber, such as a reinforced bulking finishing agent, a reinforced smooth hydrophilic finishing agent and a reinforced durable antistatic agent.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0027] The present invention will further be described in detail below with reference to examples.
Example 1
[0028] 1) The following materials are weighed as required: 800 g polyglycol with a molecular weight of 10000˜20000 (a compound with a general formula of H(OCH 2 CH 2 ) m OH), 150 g ethylene glycol, 150 g polyether dihydric alcohol with a molecular weight of 1000˜5000 (a compound with a general formula of H(OCH 2 CH(CH 3 )) n OH), 80 g two-polyether-end organosilicon, 180 g dimethyl terephthalate, and 5 g catalyst of magnesium acetate;
[0029] 2) polyglycol, ethylene glycol, and polyether polyhydric alcohol are added into the reactor, which is then heated; the reactor is vacuum-pumped when its temperature rises to 75°, making vacuum degree inside the reactor up to −0.090 Mpa; then the reactor is heated further to 90° until the materials inside are dehydrated completely; the reactor is heated to 102°; dimethyl terephthalate, two-polyether-end organosilicon and magnesium acetate are added into the reactor, which is then heated further to 150°; the materials in the reactor are pressed into the polymerizer after their complete esterification; the materials are polymerized under −0.095 MPa vacuum degree and 220° temperature conditions with magnesium acetate as the catalyst, producing the polyester/polyether/organosilicon terpolymer with a molecular weight of 1000˜50000 after complete polymerization; and then the polymerizer is cooled down to 140° to discharge the materials, producing the product.
Example 2
[0030] 1) The following materials are weighed as required: 900 g polyglycol with a molecular weight of 4000˜8000 (a compound with a general formula of H(OCH 2 CH 2 ) m OH), 120 g ethylene glycol, 120 g polyether dihydric alcohol with a molecular weight of 11000˜15000 (a compound with a general formula of H(OCH 2 CH(CH 3 )) n OH), 200 g two-polyether-end organosilicon, 165 g dimethyl terephthalate, and 5 g calcium acetate;
[0031] 2) polyglycol, ethylene glycol, and polyether polyhydric alcohol are added into the reactor, which is then heated; the reactor is vacuum-pumped when its temperature rises to 78°, making vacuum degree inside the reactor up to −0.093 Mpa; then the reactor is heated further to 95° and, after being kept at the temperature for 55 minutes, further to 104°; dimethyl terephthalate, two-polyether-end organosilicon and calcium acetate are added into the reactor, which is then heated further to 155°; the reactor is kept at this temperature for 75 minutes to make the materials in the reactor completely esterificated; then the materials esterificated in the reactor are pressed into a polymerizer; the materials are polymerized completely under −0.098 MPa vacuum degree and 240° temperature conditions with calcium acetate as the catalyst, producing the polyester/polyether/organosilicon terpolymer with a molecular weight of 5000˜40000; and then the polymerizer is cooled down to 150° to discharge the materials, producing the product.
Example 3
[0032] 1) The following materials are weighed as required: 1000 g polyglycol with a molecular weight of 1000˜5000 (a compound with a general formula of H(OCH 2 CH 2 ) m OH), 100 g ethylene glycol, 100 g block polyether of ethylene glycol and propylene glycol with a molecular weight of 5000˜9000 (an atactic copolymer with a general formula of H(OCH 2 CH 2 ) p (OCH 2 CH(CH 3 )) q OH), 150 g two-polyether-end organosilicon, 150 g dimethyl terephthalate, and 10 g zinc acetate;
[0033] 2) polyglycol, ethylene glycol, and the block polyether of ethylene glycol and propylene glycol are added into the reactor, which is then heated; the reactor is vacuum-pumped when its temperature rises to 80°, making vacuum degree inside the reactor up to −0.095 Mpa; then the reactor is heated further to 100° and, after being kept at the temperature for 60 minutes, further to 106°; dimethyl terephthalate, two-polyether-end organosilicon and zinc acetate are added into the reactor, which is then heated further to 160° to make the materials in the reactor completely esterificated; then the materials esterificated in the reactor are pressed into a polymerizer; the materials are polymerized completely under −0.1 MPa vacuum degree and 250° temperature conditions with zinc acetate as the catalyst, producing the polyester/polyether/organosilicon terpolymer with a molecular weight of 1000˜50000; and then the polymerizer is cooled down to 100° to discharge the materials, producing the product.
[0034] The present invention adopts the two-step production process for the following two reasons:
[0035] 1. In the production process, the esterification by-product is methanol, while the polymerization by-product is ethylene glycol; when the by-products (methanol and ethylene glycol) are produced and recovered in one and the same reactor system, cross contamination will occur, and distillation purification is again required. However, purity of the esterification by-product of methanol in the multiple-step process can reach over 90%, and purity of the polymerization by-product of ethylene glycol over 99%, which allow these by-products to be used as raw materials without distillation purification. Direct circular utilization can not only simplify the production process, but also follow the environmental protection trend of saving energy and decreasing consumption.
[0036] 2. In the one-step production process, with the polymerization degree increasing in the polymerization process, molecular weight of the materials will increase, and so will viscosity of the materials. The motor of the reactor is usually shut down because of overload, and cannot be started again, which results in a serious quality problem.
[0037] For example, for a 3-ton esterification reactor, if viscosity of the reactants is very low, a 5 KW motor will be enough to satisfy the requirements; for a 3-ton polymerizer, with the polymerization degree increasing, molecular weight of the materials will increase, and so will viscosity of the materials, which requires a motor of over 18.5 KW to guarantee the normal production; under normal conditions, the polymerization needs higher motor power, while the esterification lower motor power, and the stirring speed has to be fast; with the multiple-step process, the production cost can then be lowered and the quality control points increased.
[0038] The polyester fiber can be modified with the modifier produced by the production process of the present invention, making the modified polyester fiber hygroscopic, bulky and soft, thus greatly improving comfortability of the fabric made of the modified polyester fiber. In addition, the present invention further discloses that various kinds of reinforced modifiers are prepared with the modifier as the mother liquid for modifying the polyester fiber, such as a reinforced bulking finishing agent, a reinforced smooth hydrophilic finishing agent and a reinforced durable antistatic agent, as shown in the following examples.
Example 4
[0039] Bulking finishing agent: 8% (mass percent concentration) bulking finishing agent is produced by adding water to the modifier obtained from Example 1, and used in the dipping process of terry after the dyeing process at a dosage of 3% (o.m.f o.w.f, ; then the terry is dehydrated, dried and set at 50°×30 min. This bulking finishing agent can make the terry product not only bulky and soft but also smooth. O.W.F. (On weight the fabric) refers to weight of the consumption relative to weight of the fabric. For example, under certain conditions, 4% (owf) dye is consumed for dyeing 100 kg shell fabric, meaning that 100×0.04=4 kg dye is needed for dyeing this amount of shell fabric.
Example 5
[0040] Bulking finishing agent: 5% (mass percent concentration) bulking finishing agent is produced by adding water to the modifier obtained from Example 2, and used in the dipping process of the terry after the dyeing process.
Example 6
[0041] Smooth hydrophilic finishing agent: 7% (mass percent concentration) smooth hydrophilic finishing agent is produced by adding water to the modifier obtained from Example 2, and used in the dipping process of plush after the dyeing process at a dosage of 4% (o.m.f); then the plush is dehydrated, dried and set at 50°×30 mm. This smooth hydrophilic finishing agent can make the modified plush not only bulky and soft but also smooth and hydrophilic.
Example 7
[0042] Smooth hydrophilic finishing agent: 10% (mass percent concentration) smooth hydrophilic finishing agent is produced by adding water to the modifier obtained from Example 1, and used in the dipping process of the plush after the dyeing process.
Example 8
[0043] Durable antistatic agent: The smooth hydrophilic finishing agent is prepared by 8 parts of the modifier obtained from Example 2, 30 parts of WX-680A, and 62 parts of water, and used in the padding process of suede after the dyeing process at a dosage of 30 g/L, one dipping one padding (with a padding remaining rate of 70%-75%); finally the suede is dehydrated, dried, and set. This durable antistatic agent can make the modified polyester fiber not only bulky and soft but also antistatic.
Example 9
[0044] Durable antistatic agent: The smooth hydrophilic finishing agent is prepared by 5 parts of the modifier obtained from Example 3, 40 parts of WX-680A, and 55 parts of water, and used in the padding process of the suede after the dyeing process.
Example 10
[0045] Decontaminating finishing agent: The decontaminating finishing agent is prepared by 10 parts of the modifier obtained from Example 1, 1 part of glycerin, and 89 parts of water, and used in the padding process of knitting cloth after the dyeing process at a dosage of 30 g/L, one dipping one padding (with a padding remaining rate of 70%-75%); finally the knitting cloth is dehydrated, dried, and set. The decontaminating finishing agent can make the modified polyester fiber not only bulky and soft but also more decontaminating.
Example 11
[0046] Decontaminating finishing agent: The decontaminating finishing agent is prepared by 6 parts of the modifier obtained from Example 3, 3 part of glycerin, and 91 parts of water, and used in the padding process of the knitting cloth after the dyeing process.
Example 12
[0047] Bath anti-creasing agent: The bath anti-creasing agent is prepared by 8 parts of the modifier obtained from Example 2, 1 part of polyacrylamide, and 91 parts of water, and used in the dyeing-bathing blend in one step process of the terry at a dosage of 4% (o.w.f); then the terry is dyed, reducingly cleaned, dehydrated, dried, and set; that is, the modifier can be used together with polyacrylamide in one solution in a high-temperature/high-pressure dyeing machine, making the terry not only bulky and soft and anti-creasing but also improved in preventing the stiff hand feeling of polyacrylamide during usage.
Example 13
[0048] Bath anti-creasing agent: The bath anti-creasing agent is prepared by 9 parts of the modifier obtained from Example 1, 0.5 part of polyacrylamide, and 90.5 parts of water, and used in the dyeing-bathing blend in one step process of the terry.
Example 14
[0049] Hydrophilic anti-creasing high-temperature levelling agent: 10% (mass percent concentration) hydrophilic anti-creasing high-temperature levelling agent is produced by adding water to the modifier obtained from Example 1, and used in the dyeing-bathing blend in one step process of the terry at a dosage of 4% (o.w.f); then the terry is dyed, reducingly cleaned, dehydrated, dried, and set; this hydrophilic anti-creasing high-temperature levelling agent can make the modified polyester fiber not only bulky and soft but also higher in the dyeing quality, making the dyed fabric more even and bright in color.
Example 15
[0050] Hydrophilic anti-creasing high-temperature levelling agent: 20% (mass percent concentration) hydrophilic anti-creasing high-temperature levelling agent is produced by adding water to the modifier obtained from Example 2, and used in the dyeing-bathing blend in one step process of the terry.
Example 16
[0051] The polyester fiber modifier obtained from Example 1, the disperse dye red of C.I. Disperse Red 60 (60756), and the levelling agent of 600# sulfonation are added together in the dyeing process at the dyeing temperature of 120°, with weight of the modifier being 0.3% of that of the fabric.
Example 17
[0052] The polyester fiber modifier obtained from Example 3, the disperse dye red of C.I. Disperse Blue 20, and the levelling agent of 600# sulfonation are added together in the dyeing process, with weight of the modifier being 4% of that of the fabric.
Example 18
[0053] The modifier obtained froth Example 1 is applied in the dipping process of the polyester fiber fabric. This application is characterized in that the modifier is added into the dipping liquid in the dipping process, with weight of the modifier being 4% of that of the fabric.
Example 19
[0054] The modifier obtained from Example 3 is applied in the dipping process of the polyester fiber fabric. This application is characterized in that the modifier is added into the dipping liquid in the dipping process, with weight of the modifier being 0.4% of that of the fabric.
Example 20
[0055] The modifier obtained from Example 2 is applied in the padding process of polyester fiber fabric. This application is characterized in that the modifier is added into the padding tank in the padding process, with weight of the modifier being 3.5% of that of the fabric.
Example 21
[0056] The modifier obtained from Example 3 is applied in the padding process of polyester fiber fabric. This application is characterized in that the modifier is added into the padding tank in the padding process, with weight of the modifier being 0.05% of that of the fabric. | The present invention discloses a modifier for modifying the polyester fiber as well as preparation method and application of the same. The modifier contains ethylene glycol, two-hydroxy-end polyether, dimethyl terephthalate, two-polyether-end modified organosilicon, and metal acetate catalyst. A two-step continuous production process is adopted. The first step is esterification; that is, ethylene glycol, two-hydroxy-end polyether, dimethyl terephthalate, and two-polyether-end organosilicon are added into a reactor, and have an esterification reaction in the presence of the catalyst. In the second step, the materials produced by the esterification is transported to a polymerizer, and have a polymerization reaction under the conditions of high temperature, vacuum and catalyst, producing the high molecular weight polyester/polyether/organosilicon terpolymer with a molecular weight of 1000˜50000 as the desired modifier. This modifier can be used either directly or in combination with some other substances such as surfactants, so as to modify the polyester fiber. | 3 |
BACKGROUND OF THE INVENTION
This invention pertains to single hole mountable mixing faucets for washbasins and the like.
Single hole mixing faucets are known which include a hollow mounting base on a valve body through which connecting pipes and an actuating linkage for a drain valve in the washbasin are passed and which further include a discharge arm swivelable about a swivel axis.
With these devices however it is necessary to provide the sanitary pipe fittings with a fixed base section projecting out of the washbasin and to locate the actuating device for the linkage of the washbasin drain valve nearby. The swivel outlet can be positioned above the base section on the sanitary pipe fitting.
It is one object of the invention to simplify the single hole mixing battery described above and to design it so as to permit an optimum design.
SUMMARY OF THE INVENTION
A single hole mixing valve in accordance with the invention has a discharge arm which surrounds a valve body and the actuating linkage extends out of the assembly through a guide hole in discharge arm such that the linkage and discharge arm swivel together.
An arrangement in accordance with the invention permits optimum styling of the visibly located pipe fitting sections so that the drain valve actuating facility can be realized with the simplest possible means.
In an embodiment of the invention, the drain valve actuating device is a pull rod accommodated in the guide hole positioned approximately vertically in the cylindrical portion of the discharge arm whereby the deflection occurring during swivel motion is compensated for by suitable allowed clearance in the guide hole. To permit deflection of the actuating linkage a ball and socket joint is interposed in the linkage in the region of the mounting base. The section of the linkage accommodated by the pipe fitting housing can alternatively be made of an elastically flexible material. It is then possible to save using a separate ball and socket joint.
BRIEF DESCRIPTION OF THE DRAWINGS
A design example of the invention is shown by means of a longitudinally sectioned single handle mixing valve in the drawing and is described in detail below.
DETAILED DESCRIPTION
The single handle mixing valve includes a valve body 1 in which is inserted a valve unit taking the form of a cartridge 101. The valve unit can be operated by an operating lever 103 with a valve top 102 rotatably located on valve body 1.
The valve body has a hollow mounting base 2 with mounting hardware for mounting on a washbasin etc. Through the hollow mounting base 2 are passed the connecting pipes 5 for hot and cold water as well as an actuating linkage 4 for a drain valve in the washbasin which is not shown in the drawing. Above the valve body a discharge arm 3 sealed with cylindrical guides is mounted on valve body 1 so as to swivel about an inclined swivel axis 11. The discharge arm 3 in the area of the valve body takes the form of a cylindrical section which surrounds the entire body 1. On the side of the cylindrical portion 31 opposite to discharge arm 3 actuating linkage 4 is lead out of the pipe fitting with the necessary clearance in an approximately vertically positioned guide hole 9 and the end section of this linkage has an operating knob 41. So that the actuating linkage 4 can execute suitable deflection when discharge arm 3 is swivelled, a ball and socket joint 8 is interposed in the region of the mounting base 2. To permit satisfactory function of the pull rod the swivel range of the discharge arm is limited to stop elements not represented in detail in the drawing.
The mixing valve represented has the following principle of operation:
with operating level 103 it is possible by means of upward or downward movement to determine the rate of flow of the water discharged from the discharge arm 3 through an outlet nozzle 32, whilst the mixture ratio and the water mixture temperature of the water emerging can be determined by swivelling about swivel axis 11. The hot and cold water supplied in connecting pipes 5 is introduced separately into cartridge 101 and passes as mixed water out of passages 6 in valve body 1 into discharge arm 3 which surrounds this section of the valve body sealed with seal rings 7. The bottom section of cylindrical portion 31 is not impinged upon by the water and serves particularly to accommodate actuating linkage 4. When with the aid of operating knob 41 the actuating linkage 4 is pulled out of the pipe fitting, the drain valve in the washbasin not shown in the drawing is closed so that the water emerging from outlet nozzle 32 can be collected by the washbasin. The drain valve is opened by pushing actuating linkage 4 back into the pipe fitting. | A mixing faucet of the single hole mounting type and having a swivelable discharge arm includes an actuating linkage for a drain valve which is swivelable with the drain arm. | 5 |
RELATED APPLICATIONS
The following applications are related to this application and are filed on the date herewith. The disclosure of each of these related applications is incorporated by reference: Ser. No. 09/315,277, filed May 20, 1999 titled “METHOD FOR CHANGING COMMUNICATION IN A COMMUNICATION SYSTEM, AND COMMUNICATION SYSTEM THEREFOR”; Ser. No. 09/315,696, filed May 20, 1992, now U.S. Pat. No. 6,192,037 titled “METHOD FOR ESTABLISHING COMMUNICATION IN A PACKET NETWORK”; Ser. No. 09/314,908, filed May 20, 1999, titled “METHOD FOR RETRANSMITTING A DATA PACKET IN A PACKET NETWORK”; Ser. No. 09/315,314, filed May 20, 1999, titled “COMMUNICATION NETWORK METHOD AND APPARATUS”; Ser. No. 09/315,467, filed May 20, 1999, titled “METHOD AND SYSTEM FOR PROCESSING INTELLIGENT NETWORK COMMANDS IN A COMMUNICATIONS NETWORK”; Ser. No. 09/315,653, filed May 20, 1999, titled “METHOD AND SYSTEM FOR NETWORK SERVICE NEGOTIATION IN A TELECOMMUNICATIONS SYSTEM”; Ser. No. 09/315,309, filed May 20, 1999, titled “SESSION BASED BILLING IN A COMMUNICATION SYSTEM”; Ser. No. 09/315,466, filed May 20, 1999, titled “METHOD AND SYSTEM FOR INTRODUCING NEW SERVICES INTO A NETWORK”.
FIELD OF THE INVENTION
The present invention relates generally to a communications system, and more particularly, to a method and apparatus for routing data within the communications system. Still more particularly, the present invention relates to a method and apparatus for increasing the quality of a network transmission between a first node a second node, and a method for providing soft handoff in a cellular communications system.
BACKGROUND OF THE INVENTION
In a conventional telecommunications switching network, a communications path must be established in a source node and a destination node before data, such as facsimile, email, or voice, can be distributed along the established path. A propagation delay occurs across the network when setting up and releasing a communication path. Conventional telecommunications switching systems, upon deriving a destination of a telephone call, must send a message to a remote database system to request routing information for a particular call. Remote database systems provide a menu of routing information, and routing information is selected from the database system according to the request from a telecommunications switching system.
Code division multiple access (CDMA) systems must support the transport of digitally encoded information that is in packet form. In addition, CDMA systems must support multiple duplicated streams of this information, known as soft handoff, and carry this information in an efficient manner over transport links within the system. Large CDMA systems may require different networking technology. Implementation of an Internet Protocol (IP) based network can solve transparency issues with the network by providing the inter networking function above the physical and transport network layers. The cost of network equipment in a CDMA system is a problem because of the large number of network paths required because of the use of soft handoff. Another problem with the large number of network paths in a CDMA system is the complexity of manipulation and management of these paths in a connection oriented implementation. IP allows a connection less or routed architecture that greatly simplifies network implementation. Unlike other technologies such as Asynchronous Transfer Mode (ATM), the use of differentiated services to assign and/or control quality of service (QoS) enables this to be done in a connectionless manner in the core network where bandwidth is prevalent.
In addition, a routed network enables a peer-to-peer network element relationship rather than the classical hierarchical network. A peer-to-peer network allows for entity relationships such as client/server which offers improved and flexible possibilities for scalability and network robustness.
It is, therefore, desirable to have an improved method and apparatus for routing packet data in a communications system, wherein the quality of a network transmission between a first node and a second node is increased.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objects, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
FIG. 1 depicts a block diagram of a communications system in which the present invention may be implemented;
FIG. 2 depicts a block diagram of data structures according to the present invention used to transfer data within a communications system;
FIG. 3 depicts a block diagram of an embodiment of the present invention;
FIG. 4 depicts a block diagram of an alternate embodiment of the present invention; and
FIG. 5 depicts a more detailed block diagram of an embodiment of the present invention as it relates to a CDMA system.
DETAILED DESCRIPTION OF THE INVENTION
With reference now to the figures, and in particular with reference to FIG. 1, a communications system 100 is depicted in which the present invention may be implemented. Communications system 100 includes an interconnect network, which may be a packet system but which in the preferred embodiment is an IP network which processes data streams from various sources, such as voice, data, image, and video. IP network 102 receives and sends data to and from cellular regions 104 and 106 . Cellular region 104 includes base termination sites (BTSs) 108 - 112 , which send and receive radio signals to and from mobile telephones and packetize the communications content of the radio signals into electronic data transported within data packet units. The packets are sent to IP network 102 over the span lines connecting BTSs 108 - 112 . These span lines may be T 1 or E 1 lines connecting the BTS to IP network 102 . Similarly, cellular region 106 contains BTSs 114 - 118 , which also receive radio signals, packetize these signals into data packet units, and send the data packet units to IP network 102 over the span lines connecting BTSs 114 - 118 to IP network 102 .
Data can be sent to mobile telephone units, such as mobile unit 120 , from IP network 102 through transmissions from BTSs located in each of the cellular regions. A mobile unit 120 traveling within cellular region 106 transmits radio signals for a call that may be received by more than one BTS, such as BTSs 116 and 118 . Each BTS receiving a radio signal from mobile unit 120 will transmit data to IP network 102 , via the span lines. At some point, only one of the two BTSs will receive radio signals from the mobile unit 120 because the mobile unit 120 will have traveled out of the range of that BTS. Similarly, a mobile unit may receive a radio signal from more than one BTS depending on the location of mobile unit 120 . This receiving of radio signals at multiple BTSs for a signal call is associated with soft handoff (SHO).
With reference now to FIG. 2, a block diagram of data structures used to transfer data in communications system 100 in FIG. 1 is depicted according to the present invention. Packet 200 is an electronic data packet in the form of a code division multiple access (CDMA) packet received within one of the BTSs shown in FIG. 1, such as BTS 118 . Packet 200 includes data streams associated with CDMA. When received at BTS 118 , packet 200 is transformed into a packet data unit (PDU) 202 . PDU 202 is sent to IP network 102 . PDU 202 is an example of the data structure used within IP network 102 to carry data from source nodes to destination nodes. PDU 202 comprises a content which includes a header portion 204 and, a payload portion 206 . Header portion 204 includes information used to route the PDU 202 along with other overhead information. Data is placed within payload portion 206 .
With reference now to FIG. 3, a communications system 300 is depicted in which the present invention may be implemented. Communications system 300 includes an IP network 302 which processes data streams from various sources, such as voice, data, image, and video. IP network 302 receives and sends data to and from cellular regions 304 and 306 . IP network 302 includes access node/router 303 , which sends and receives data streams to and from base termination sites 308 and 318 . Cellular region 304 includes base termination site (BTS) 308 , which sends and receives radio signals to and from mobile telephones and packetizes the communications content of the radio signals into electronic data transported within data packet units. The packets are sent to IP network 302 over the span lines connecting BTSs 308 and 318 . Alternatively, the packets may be sent over fiber, microwave, etc. Similarly, cellular region 306 contains BTS 318 , which also receives radio signals, packetizes signals into data packet unit, and sends the data packet units to IP network 302 over the span lines connecting BTS 318 to IP network 302 . With regard to downlink traffic, access node/router 303 receives an incoming data stream from a node within IP network 302 , the data stream having a content including a header portion and a payload portion. Within node 303 , two packets are created having the content, one of the packets being sent to BTS 308 and the other of the packets being sent to BTS 318 . In the preferred embodiment, the two packets are transmitted via two different logical channels over a shared broadband spectrum to a second node, which, as shown in FIG. 3, is mobile unit 320 . At mobile unit 320 , an estimated packet is created having an estimate of the content in response to the two packets received from BTS 308 and BTS 318 . In a CDMA system, the creation of an estimated packet includes aligning the packets received from BTS 308 and BTS 318 , and summing the packets received from BTS 308 and BTS 318 . In an alternate embodiment, a quality of service (QoS) function may be added, the QoS function being described in more detail below.
Referring to FIG. 4, a block diagram of an alternate embodiment of the present invention is shown at 400 , wherein access node/router 404 receives an incoming data stream from selection/distribution node 402 , the data stream having a content. Within node 404 , the data packet is replicated, whereby two packets are created having the content, one of the packets being sent to transmitter 406 and the other of the packets being sent to transmitter 408 . Subsequently, the replicated packet is sent or transmitted to node 410 . At node 410 , an estimated packet is created having an estimate of the content in response to the two packets received from transmitters 406 and 408 . In an alternate embodiment, a quality of service function 412 may be added, the quality of service function 412 providing a mechanism to weigh the cost of resources and the system availability of resources. This facilitates the decision to maintain or remove one or more of the multiple paths being used in the network connection between nodes 404 and 410 . For example, a decision can be made about the quality of each of the multiple paths, thereby enabling one of the paths to be selected over another one of the paths or even enabling one of the paths to be torn down.
With reference now to FIG. 5, a block diagram of an embodiment of the present invention as it relates to a CDMA system is shown wherein soft handoff with paths including BTS-A and BTS-B is shown. As seen in FIG. 5, in the preferred embodiment, each physical bearer end point will be individually IP addressable. For example, in BTS-A 504 , channel 1 has the IP address IP:A 1 , channel 2 has the IP address IP:A 2 , etc. In BTS-B 506 , channel 1 has the IP address IP:B 1 , channel 2 has the IP address IP:B 2 , etc. Referring to the selector 508 , the address for channel (N) is IP:S(N). Referring to the vocoder 510 , the IP address of vocoder (N) is IP:V(N). Traffic is routed among the physical elements via standard IP routing and, in the preferred embodiment, by a connectionless IP protocol such as UDP for transport of bearer traffic. For example, uplink traffic (e.g., BTS to vocoder) is routed as follows:
channel element BTS-A- 1 to selector channel 1 (source IP address IP:A 1 , destination IP address IP:S 1 )
channel element BTS-B- 1 to selector channel 1 (source IP address IP:B 1 , destination IP address IP:S 1 )
selector channel 1 to vocoder 1 (source IP address IP:S 1 , destination IP address IP:V 1 )
The reverse is generally true for the downlink except that in the preferred embodiment, IP multicast such as Internet Group Management Protocol (IGMP) is used to allow the distribution function to provide a copy of an incoming sample stream to each of the multiple BTSs involved in soft handoff. In this case, channel element BTS-A- 1 (IP:A 1 ) and channel element BTS-B- 1 (IP:B 1 ) belong to a common multicast group that the distribution function (selector channel 1 ) sends to. As the call configuration changes, soft handoff legs add and drop, and BTS channel elements enter and leave the multicast group, respectively.
Referring back to FIG. 5, the following description pertains to tracing the voice path through the system 500 for the downlink. Voice will flow from the PSTN (not shown) to vocoder 510 . An alternative flow may be from the internet or other multimedia device through unit 518 and then to selection/distribution unit 508 . Voice can be carried by that path as well (e.g., voice over IP). The voice stream thereafter gets fed over to the selection/distribution unit 508 . More particularly, the voice stream flows out the IP path coupling vocoder 510 and IP routing/switching unit 514 and thereafter gets routed to selection distribution unit 508 . In other words, the voice stream is essentially an IP datagram that is routed to a specific selection/distribution unit that is handling this particular call. The data packet is thereafter replicated via IGMP in one of the access node/routers 512 , 516 or IP routing/switching unit 514 .
IP routing/switching unit 514 and access nodes 512 , 516 essentially provide media adaptation and IP datagram routing. IP routing/switching unit 514 in essence just takes in an IP datagram and routes it. Access nodes or routers 512 , 516 typically bring in a plurality of fairly low speed links such as T 1 and multiplexes those at that point.
Subsequently, the replicated packet is sent via different paths to BTS-A 504 and BTS-B 506 . Thereafter, each of the BTSs 504 and 506 will take the payload out of the packet and convert the payload into a form that is suitable for wireless transmission and thereafter transmit the packet in a synchronized fashion or a timed aligned fashion to the mobile subscriber unit 502 . It should be noted that the same flow as described above for a voice path could occur for data such as data off of the internet or a multi-media service as shown at alternative data path unit 518 .
It is contemplated that the mobile subscriber 502 itself be the IP capable end point. In that instance, mobile subscriber 502 is then the multicast group and the BTSs 504 and 506 then act as multicast routing proxies as members of the IP network. As a mobile moves (hands off) from one BTS to another, the multicast routing tree is updated as other BTSs get involved and/or leave the call.
IP multicast via a protocol such as internet group management protocol (IGMP) can also be used to distribute control messages, such as mobile paging requests, from a central control function such as controller 520 to the BTSs 504 and 506 . For example, each paging area may correspond to a unique multicast group. BTSs that belong to a given paging area would join the multicast group associated with that area. Each BTS may be a member of multiple paging areas and thus would belong to multiple multicast groups. To deliver a page, the controller 520 would send a page control message to the multicast group associated with the paging area to be paged. Only the BTSs that need to actually page the subscriber will receive the page control message. Simple broadcast can also be used for this function or when the page is effectively a “page all” request. The aforementioned also may be applied to realize other features such as short message service (SMS).
The foregoing description of a preferred embodiment of the invention has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen and described to provide the best illustration of the principles of the invention and its practical application, and to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. | A method and apparatus for routing packet data in a communications system. The method includes receiving a first path packet at first node, the first path packet having a content, creating two packets having the content, sending the two packets via different paths to a second node, and creating an estimated packet including an estimate of the content in response to the two packets received at the second node. In addition, a method for providing soft handoff in a cellular communication system is provided, the method including receiving a first path packet at a first node, the first path packet having a content within the first node, creating two packets having the content, sending the two packets to a transmitter, transmitting the two packets via two different radio channels to a second node, and creating an estimated packet including an estimate of the content in response to the two packets received at the second node. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a Non-provisional of, and claims benefit and priority to, U.S. Provisional Patent Application No. 62/122,209 filed on Oct. 14, 2014, the entirety of which is hereby incorporated by reference herein.
BACKGROUND
Embodiments disclosed herein generally relate to fire-tube boilers and provide solutions to the problem of cleaning the interior surface of fire-tubes with a lighter weight, easier to use machine.
The general construction of a fire-tube boiler is a tank of water penetrated by tubes that carry the hot flue gases from the boiler's combustion chamber. The tank is usually cylindrical for the most part (being the strongest practical shape for a pressurized container) and this cylindrical tank may be either horizontal or vertical. In a fire-tube boiler a large number of fire-tubes are arranged in a boiler drum for generating a large amount of steam (hot water) for its size as compared to flue boilers. Hot combustion gases pass through fire-tubes running through the sealed boiler drum containing water. The heat of the gases is transferred to the water through the walls of the tubes ultimately creating steam. The many small tubes offer far greater heating surface area for the same overall boiler volume. In operation, surface area heat transfer efficiency is diminished by buildup on the fire-tube interior surfaces by products of corrosion, oxidation, soot, and chemical reactions. Fire-tube boiler cleaning machines are available for tube cleaning, however, such machines are very heavy and hard to use in tight spaces or on elevated catwalks, platforms, or scaffolding. Machine weight is determined by the physics of pushing a rigid cleaning brush in a forward stroke down the full length of a tube by means of a steel tape. The steel tape needs to be thick and heavyweight to resist the significant compressive forces encountered in pushing the brush along the tube. Additionally, the machine needs sufficient mass (weight) to withstand the high loads developed on the brush forward stroke.
Some embodiments disclosed herein deal with the main problem of conventional fire-tube cleaners, i.e., the weight of the cleaner and component parts. Solutions disclosed herein provide a unique and brilliant way of substituting fire-tube boiler mass for the mass needed by conventional machines to withstand the high loads developed on the brush forward stroke. Embodiments disclosed herein generally, for example, take advantage of boiler mass by providing a machine for tube cleaning on reverse stroke.
SUMMARY
Fire-tube cleaners according to embodiments described herein utilize lightweight, high strength components to propel a unique easy-push, clean on return stroke brush for tube cleaning. Brush design minimizes friction resistance on the forward stroke of the cleaning cycle, thereby substantially reducing compressive force on the tape pushing the brush and eliminating tendency of tape to collapse, buckle, or bind within a tube. On the return cleaning stroke the tape is in constant tension and can easily handle the forces involved. A preferred embodiment is designed for modern package boilers usually having tubes of maximum length of sixteen (16) feet and of outside diameter of two inches (2″) to two and one half inches (2½″).
An operator of the fire-tube cleaner according to some embodiments pre-sets the distance the tape and brush travel according to boiler tube length thereby allowing the operator to concentrate on machine and cleaning cycle. This feature eliminates operator need to concentrate on machine distance monitor to avoid cleaning brush slamming into the far side of the boiler damaging boiler cover, insulation, cleaning brush, etc.
The machine may also or alternatively include a distance monitor on both sides of the machine, a centrally located rear-mounted operating switch, and a main drive-train of motor, gearbox, clutch, and final drive located within the machine protecting the operator from moving parts and hot (e.g., one hundred and eighty degrees Fahrenheit (180° F.)) exposed drive motor. The machine allows for quick change of steel tape without the need for machine disassembly.
An easy-push, clean on return stroke brush reduces push force through fire-tubes. The brush may be mounted on a restricted movement swivel that allows the brush to fold over passing down the tube, and to setup and remain upright on the return stroke.
Specific examples are included in the following description for purposes of clarity, but various details can be changed within the scope of the present invention.
OBJECTS OF THE INVENTION
An object of the invention is to provide a machine for cleaning tubes.
An object of the invention is to provide a machine for cleaning fire-tubes that cleans tubes on brush return stroke thereby to take advantage of boiler mass and reduce cleaning machine mass.
Another object of the invention is to provide a lightweight fire-tube cleaner with reduced resistance on brush push stroke and with tube cleaning occurring on the return stroke.
Another object of the invention is to provide a fire-tube cleaning machine with lightweight, high strength steel tape to propel brush down the tube.
Another object of the invention is to provide fire-tube cleaning machine with preset travel distance for tape selected according to fire-tube length.
Another object of the invention is to provide for tube cleaning machine with drive train located within the machine for operator protection.
Other and further objects of the invention will become apparent with an understanding of the following detailed description of the invention or upon employment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
An understanding of embodiments described herein and many of the attendant advantages thereof may be readily obtained by reference to the following detailed description when considered with the accompanying drawings, wherein:
FIG. 1 is a perspective view of a preferred embodiment of a fire-tube cleaner according to some embodiments;
FIG. 2 is a side elevation view of the fire-tube cleaner of FIG. 1 with first side cover plate removed to illustrate interior components;
FIG. 3 is a reverse side perspective view of the fire-tube cleaner of FIG. 1 and FIG. 2 with second side cover plate removed to illustrate interior components;
FIG. 4A is fragmentary side view of interior working components of a distance indicator;
FIG. 4B is a perspective view of interior working components of a distance indicator;
FIG. 5 is a front elevation view of the distance indicator cover shown in FIG. 1 and FIG. 4B ;
FIG. 6 is a fragmentary perspective view of a steel tape reel in open position for change of tape;
FIG. 7 is a fragmentary perspective view of a steel tape reel in closed position for tape operation in tube cleaning;
FIG. 8 is a perspective view of a cleaning brush in a position for feeding into a fire-tube on forward stroke; and
FIG. 9 is a perspective view of a cleaning brush in a position for cleaning a fire-tube on return stroke.
DETAILED DESCRIPTION
Referring to FIG. 1 , FIG. 2 , and FIG. 3 of the drawings, a fire-tube cleaning machine 10 includes housing 12 defined by confronting shell members 12 a - b defining an interior space 14 for placement of cleaner operating components 16 including drive-train 18 and tape reel 20 with drum drive gear 20 a . The housing further includes carry handle 12 c , cover plate 12 d for access to tape anchor 36 (also shown in FIG. 6 and FIG. 7 ), vacuum connection 12 e , and cleaner switch console 12 f . The shell members 12 a - b are secured to each other by suitable fasteners (not shown) at multiple locations 12 g.
A tape 22 and brush and/or brush assembly 24 may be housed in a deployment member in the form of a tape outlet barrel 26 that extends from the housing 12 for insertion into individual fire-tubes 28 so as to position tape 22 and brush assembly 24 at tube entry 28 a . The tape outlet barrel 26 serves as a vacuum conduit for carrying dislodged soot from each tube 28 to a vacuum source (not shown) at vacuum connection 12 e.
A distance indicator 30 (described in detail below) may be affixed to a side of housing 12 exterior for pre-setting distance of tape travel according to length of boiler fire-tubes 28 .
Layout of interior components according to some embodiments is shown in FIG. 2 and FIG. 3 including tape reel 20 with its drive gear 20 a and tape anchor 36 , and tape reel drive train 18 .
Drive train 18 may include, for example, an electric drive motor 18 a suitably powered with drive shaft 18 b rotating at one end a cooling fan 18 c , and worm gear box 18 d at other end. Output pinion 18 f is positioned between gear box 18 d and clutch 18 e . Out-put pinion 18 f is driven by worm gear (not shown; housed inside of the worm gear box 18 d ) to power drive chain or belt 18 g for turning tape reel 20 by its drive gear 20 a . Power switch 32 has forward, center, and reverse positions for directing rotation of the drive motor 18 a . Tape reel 20 is equipped with a reel stop 20 c for stopping the reel 20 (e.g., by a stop surface 20 cx engaging with a stop portion 20 x of the reel 20 , such as by the reel stop 20 c rotationally engaging therewith by rotating about a stop pivot 20 cy ) so tape holder or anchor 36 may be stopped/located at housing access panel 12 d (e.g., for access to allow tape changeover and/or maintenance or adjustment).
The distance indicator 30 on one or both sides of the housing 12 sets the distance of payout of tape 22 on brush forward stroke according to the length of fire-tubes 28 in a particular boiler (not shown). Referring to FIG. 4A , the distance indicator 30 has a first limit switch 30 i providing an “off” function for the drive motor 18 a at the end of a length of tape 22 paid out on forward stroke. The operator uses forward/reverse switch 32 on return stroke to pull tape 22 and brush assembly 24 in a cleaning pass through a fire-tube 28 . On return stroke the distance indicator 30 trips a second limit switch 30 j for providing an “off” function for drive motor 18 a . A distance adjustment control knob 30 m ( FIG. 1 ) is movable through an adjustment arc defined by an arced slot 30 k ( FIG. 1 and FIG. 4B ) in distance indicator 30 for setting payout distance of the tape 22 .
Reel drive gear or sprocket 20 a is fitted with distance indicator drive pinion 20 d for powering distance indicator 30 . Distance indicator 30 includes outer cover 30 a secured by retaining bolt 30 b at socket 30 c formed in a housing shell member 12 a or 12 b with indicator sprocket gear 30 e ( FIG. 4B ) meshed with teeth of the distance indicator drive pinion 20 d . Inner web 30 f ( FIG. 4B ) of the indicator sprocket gear 30 e is provided with a movable forward actuator 30 g (also shown in FIG. 2 as engaged with first limit switch 30 i —although with the indicator sprocket gear 30 e is not shown in FIG. 2 ) and a stationary or fixed rearward actuator 30 h cooperating with the first or forward limit switch 30 i and with the second or rearward limit switch 30 j , which may for example, comprise micro-switches. Forward actuator 30 g comprises an arcuate bar at a first fixed radius R 1 from sprocket center 30 b - 1 (e.g., coincident with a center axis of the retaining bolt 30 b ), the bar being slidable along the arced slot 30 k formed in the sprocket web 30 f . The forward actuator fixed radius R 1 is equal to a distance between the sprocket center 30 b - 1 and a contact surface of the first limit switch 30 i . Forward actuator 30 g and forward limit switch 30 i cooperate (e.g., as depicted in FIG. 2 ) to stop tape 22 and brush assembly 24 forward movement into the fire-tube 28 . Rearward actuator 30 h is affixed to circular rib 30 n (and/or comprises a raised portion of the circular rib 30 n ) positioned on inner web 30 f at a second fixed radius R 2 from sprocket center 30 b - 1 . The second fixed radius R 2 is equal to a distance between the sprocket center 30 b - 1 and the rearward limit switch 30 j.
FIG. 1 and FIG. 5 show distance indicator cover 30 a with slot 30 k and indicator knob 30 m . The distance travelled forward into a tube by tape 22 and brush assembly 24 in a tube cleaning pass is selected by moving knob 30 m (and accordingly the attached/cooperative forward actuator 30 g ) along slot 30 k . As shown in FIG. 5 , indicator cover 30 a has indicia “I” arranged along its circumference with a portion of indicia “I”, i.e., labels representing numbers/settings seven (7) through sixteen (16), arranged alongside slot 30 k . The indicia “I” correlates to tube length, and by positioning knob 30 m adjacent a specific value representing a desired/known tube length, the operator thus selects distance cleaning brush assembly 24 travels on forward stroke. The knob 30 m has a threaded connection (not shown) with forward actuator 30 g for tightening forward actuator 30 g in selected position in the slot 30 k . In operation, rearward actuator 30 h stops tape movement when sprocket 20 a (e.g., via engagement of the distance indicator drive pinion 20 d ) brings the rearward actuator 30 h into contact with the rearward limit switch 30 j , as occurs when the tape 22 and brush assembly 24 are withdrawn from a tube 28 . Forward movement of tape 22 and brush assembly 24 in another tube 28 occurs with forward actuation of operating switch 32 by machine operator. Forward movement of tape 22 and brush assembly 24 continues for a pre-selected distance corresponding to the dialed-in position of forward actuator 30 g . Forward movement of tape 22 and brush assembly 24 stops when movable forward actuator 30 g trips the forward limit switch 30 i . At this point operator uses main switch 32 to reverse tape 22 and brush assembly 24 movement drawing them rearward in a cleaning pass through a tube 28 .
FIG. 6 and FIG. 7 show tape reel or drum 20 for forward unwinding and reverse rewinding of tape 22 for cleaner operation. Tape 22 may comprise a stainless steel band having strength and stiffness capable of pushing tube cleaning brush assembly 24 described herein through the length of a fire-tube 28 , of pulling the brush assembly 24 back through the tube 28 in a cleaning stroke, and having a suitable level of pliability to coil about the tape reel 20 . While typical fire-tube cleaning tape (not shown) must be designed of a sufficient width and thickness to provide approximately two hundred (200) pounds of push force, for example, the tape 22 in accordance with embodiments herein may generally be about half the width and thinner than typical tape, such that the tape 22 of the fire-tube cleaning machine 10 described herein may be designed and configured to maintain structural integrity upon an application of approximately one hundred (100) pounds of push-force. In such a manner, for example, the tape 22 may be approximately one half the weight of typical tapes, significantly reducing the overall wright of the fire-tube cleaning machine 10 as compared to previous cleaning machines for fire-tubes.
In some embodiments, on reverse stroke the reel stop 20 c positions tape notches 22 a adjacent access panel 12 d . Tape 22 has end notches 22 a for engagement with a movable anchor 36 fitted to the reel 20 . A spring loaded platform 36 a positions anchor pins 36 b in engagement with notches 22 a for securing tape 22 to reel 20 . Platform 36 a is lowered to disengage pins 36 b from notches 22 a when tape 22 is replaced. Spring 36 c urges platform 36 a and pins 36 b into normal position of anchoring pins 36 b to tape notches 22 a . Cover plate 12 d ( FIG. 1 and FIG. 3 ) provides access to platform 36 a and tape notches 22 a so that tape 22 can be changed without dismantling the cleaner housing 12 . Rollers 34 remove binding friction on the tape 22 when outward bound into a tube 28 .
FIG. 8 and FIG. 9 illustrate brush assembly 24 of cleaning brush 24 a and brush head 24 b . Cleaning brush 24 a is attached to tape 22 by means of brush head 24 b . Brush head 24 b comprises an elongate block 24 c with center recess 24 d for insertion and securing tape end 22 b to the block 24 c using suitable fasteners 24 e . Block end 24 f has spaced arms 24 g - h defining between them a socket 24 i for receiving cleaning brush subassembly of brush 24 a and brush post 24 j . Brush post 24 j is nested within socket 24 i and secured to arms 24 g - h by pivot pin 24 k for pivotal movement of brush 24 a and brush post 24 j from horizontal to vertical positions of FIG. 8 and FIG. 9 , respectively. Brush subassembly has normal position as shown in FIG. 8 , and sets up to vertical position when tape 22 is in reverse stroke pulling brush 24 a through a fire tube 28 . The brush 24 a itself is mounted by securing bolt 24 m on brush post 24 j for free-wheeling rotation about brush axis X-X′. In some embodiments, the term “vertical” may be descriptive of (and/or specifically defined as) the brush 24 a being oriented such that a centerline of the securing bolt 24 m (not separately labeled) is oriented along the X-X′ axis. According to some embodiments, the term “horizontal” may be descriptive of (and/or specifically defined as) the brush 24 a being oriented such that the centerline of the securing bolt 24 m (not separately labeled) is oriented perpendicular to the X-X′ axis.
The brush 24 a includes cleaning strips or blades 24 n of suitable material extending radially from brush axis X-X′. The brush strips 24 n may be pitched at an angle to brush axis X-X′ to promote rotation and cleaning action of the brush 24 a as it travels in reverse stroke through a fire-tube 28 .
The underside of brush head 24 b defines a recess 24 p to accommodate positioning of the brush 24 a horizontally ( FIG. 8 ). The tape 22 and brush assembly 24 are in position of FIG. 8 on forward stroke for pushing brush 24 a through a fire-tube 28 to initiate cleaning operation. For a reverse stroke or cleaning pass, the tape 22 pulls brush 24 a back through a fire-tube 28 . In this cleaning pass, the brush 24 a pivots to vertical ( FIG. 9 ) with brush tips (not separately labeled) engaging interior fire-tube surface (not shown) while rotating and scrubbing soot and other dirt and contaminants (not shown) from the tube 28 . A vacuum source (not shown) secured to machine vacuum connection 12 e draws scrubbed material (not shown) from fire-tube 28 through machine barrel 26 .
In use of the fire-tube cleaning machine 10 , an operator sets distance indicator 30 according to fire-tube length for a particular boiler (not shown). With brush assembly 24 in position of FIG. 8 , operator advances the brush assembly 24 in a forward stroke by reeling out the tape 22 the set distance. Diametrically opposed edges of brush blades 24 n slip along interior fire-tube surface with minimum resistance. Here the chief requirement of the machine 10 is for a tape 22 of sufficient strength to push against this minimum resistance. The need for a massive conventional machine to support a forward stroke cleaning pass is eliminated. For cleaning the fire-tube 28 , the tape 22 is pulled through reverse stroke with brush assembly 24 setting up to position of FIG. 9 with entire complement of blade tips scrubbing tube interior. On the reverse pass, the boiler (not shown) provides mass and cleaning machine 10 provides lightweight, high strength structure for pulling brush 24 a back through each tube 28 .
Various changes may be made to the structure embodying the principles of the embodiments described herein without deviating from the scope of the overall invention. The foregoing embodiments are set forth in an illustrative and not in a limiting sense. The foregoing description has particular reference to cleaning boiler fire-tubes, however, it is understood that the cleaning machine described herein may be used for a wide variety of tube cleaning applications.
The present disclosure provides, to one of ordinary skill in the art, an enabling description of several embodiments and/or inventions. Some of these embodiments and/or inventions may not be claimed in the present application, but may nevertheless be claimed in one or more continuing applications that claim the benefit of priority of the present application. Applicants intend to file additional applications to pursue patents for subject matter that has been disclosed and enabled but not claimed in the present application. | A tube cleaning machine in which cleaning interior tube surfaces occurs by a forward non-cleaning pass of cleaning implement through work tube followed by reverse cleaning pass where implement engages and cleans interior surface. Cleaning implement has first position for forward pass producing minimum engagement of interior fire-tube surface, and a second position for reverse pass of full cleaning engagement with interior fire-tube surface. A distance indicator enables operator to select distance of forward pass of cleaning implement to correspond with tube length. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to the field of nonaqueous electrolytic solutions and batteries using the same. More particularly, this invention pertains to nonaqueous electrolytic solutions comprising (a) one or more solvents; (b) one or more ionic salts; and (c) one or more nitrogen silylated compounds. Rechargeable batteries comprising such nonaqueous electrolytic solutions are disclosed herein as well as methods of making nonaqueous electrolytic solutions with nitrogen silylated compounds to scavenge moisture and free acid in lithium batteries and lithium ion batteries.
[0003] 2. Description of Related Art
[0004] Electric current producing cells such as batteries consist of pairs of electrodes of opposite polarity separated by electrolytic solution, which includes a solvent and a solute. The charge flow between electrodes is maintained by an ionically conducting solute, i.e., a salt. The non-aqueous electrolytic solutions, which are used in lithium and lithium ion batteries, are made by dissolving lithium salts in a variety of organic solvents. In particular, nonaqueous electrolytes comprising lithium hexafluorophosphate (LiPF 6 ) exhibit very good electrochemical stability and conductivity. However, LiPF 6 is not thermally stable and readily decomposes by hydrolysis, as set forth in the following well-known reactions:
LiPF 6 →LiF+PF 5 (1)
LiPF 6 +H 2 O→2HF+LiF+POF 3 (2)
[0005] Thermal decomposition of LiPF 6 occurs at elevated temperatures (Reaction 1), and is accelerated in solution due to the reactions of PF 5 and solvents. Hydrolysis (Reaction 2) generally occurs due to moisture and acidic impurities in the lithium salt and electrolytic solution. Accordingly, both water and hydrogen fluoride (HF) are undesirable in lithium and lithium-ion battery systems. The strong acid HF is especially harmful to batteries because it reacts with electrode active materials and corrodes the solid electrolyte interface (SEI), which results in poor battery performance. Thus the performance of such an electrolytic solution, and hence of a battery made therewith, is not optimal.
SUMMARY OF THE INVENTION
[0006] The present invention provides a stable nonaqueous electrolytic solution for use in secondary batteries, and a secondary battery using the same. In particular, the present invention provides a secondary battery comprising an anode, a cathode, and an electrolytic solution. The electrolytic solution comprises a non-aqueous solvent, a salt, and a nitrogen silylated compound. It is believed that the use of a nitrogen silylated compound in a secondary battery is novel. A battery made with the non-aqueous electrolytic solution comprising a nitrogen silylated compound has a long cycle life and high discharge capacity retention. The present invention provides a nonaqueous electrolytic solution comprising a nitrogen silylated compound. The nitrogen silylated compound acts as a scavenger for moisture and free acid in lithium batteries and lithium ion batteries.
[0007] The present invention provides a nonaqueous electrolytic solution comprising a nitrogen silylated compound. Nitrogen silylated compounds, which are electrically neutral, act as scavengers for moisture and free acid in electrolytic solutions and lithium ion batteries.
[0008] The electrolytic solution in the present invention comprises (a) one or more solvents and (b) one or more lithium salts; and (c) one or more nitrogen silylated compounds. Typical lithium salts include LiPF 6 , LiBF 4 , LiB(C 2 O 4 ) (i.e. LiBOB), however others may be used. Solvents include ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethylmethyl carbonate (EMC), gamma-butyrolactone (GBL), methyl butyrate (MB), and propyl acetate (PA), however other non-aqueous solvents could be used. The nitrogen silylated compound has Formula (I) wherein R 1 , R 2 , and R 3 are each independently a C 1 -C 20 hydrocarbon residue.
[0009] In particular, the invention provides a secondary battery comprising an anode, a cathode comprising lithium, and an electrolytic solution. The electrolytic solution comprises a non-aqueous solvent, a salt, and an nitrogen silylated compound having the formula (I) wherein R 1 , R 2 , and R 3 are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, and aryl residue, wherein X and Y are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, aryl, —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, —NR 9 —, —NR 10 R 11 , —PR 12 —, and —Si(R 13 R 14 ). Substituents R 9 to R 14 are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, and aryl. Substituent Z is selected from the group consisting of nothing, a direct bond between X and Y, —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, —N(R 15 )—, —NR 16 R 17 , —PR 18 —, —Si(R 19 R 20 )—, and [C(R 21 ) 2 ] m —. Substituents R 15 to R 21 are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, and aryl, and m is a number from 1 to 6.
[0010] The invention further includes a method of making a lithium battery or lithium ion battery comprising providing an electrolytic solution comprising a non-aqueous electrolytic solvent and a lithium containing salt, and an additive having the formula (I) wherein R 1 , R 2 , and R 3 are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, and aryl residue, wherein X and Y are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, aryl, —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, —NR 9 —, —NR 10 R 11 , —PR 12 —, and —Si(R 13 R 14 )—. Substituents R 9 to R 14 are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, and aryl. Substituent Z is selected from the group consisting of nothing, a direct bond between X and Y, —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, —N(R 15 )—, —NR 16 R 17 , —PR 18 —, —Si(R 19 R 20 )—, and [C(R 21 ) 2 ] m —. Substituents R 15 to R 21 are each independently selected from the group consisting of hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, and aryl, and m is a number from 1 to 6; laminating and winding a cathode, a first porous separator, an anode, and a second porous separator; placing the wound laminated electrodes and separators in a battery case; infusing the electrolytic solution into the battery case, and sealing the battery case containing the electrodes, electrolytic solution and separators.
[0011] These and other features and advantages of the present invention will become readily apparent to those skilled in the art upon consideration of the following detailed description that described both the preferred and alternative embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a graphical depiction of the charge and discharge capacities over 100 cycles of charge and discharge of the battery of Example 5.
[0013] FIG. 2 is a graphical depiction of the discharge capacity of working Examples 2, 4, 5, and 9, over a 100 cycle trial.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The following embodiments describe the preferred and alternative modes presently contemplated for carrying out the invention and are not intended to describe all possible modifications and variations consistent with the spirit and purpose of the invention. These and other features and advantages of the present invention will become more readily apparent to those skilled in the art upon consideration of the following detailed description that described both the preferred and alternative embodiments of the present invention.
[0015] Nitrogen silylated compounds are strongly hygroscopic. Upon contact with residual moisture in an electrolytic solution, they form a siloxyl compound and an amine compound. The latter product can then react with the free acid in the electrolytic solution to form a quaternary ammonium salt. In this way, both the moisture and free acid content in the electrolytic solution decreases.
[0016] Broadly, a secondary battery (and a method of making such a battery) is disclosed, which comprises an anode, a cathode and an electrolytic solution. The electrolytic solution comprises a non-aqueous solvent, a solute (i.e., a salt) and a nitrogen silylated compound additive. These major ingredients are detailed hereinbelow.
[0017] Nitrogen silylated compound. The nitrogen silylated compound may be represented by the general Formula (I):
[0018] In the formula, R 1 , R 2 and R 3 are each independently a hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl or aryl. Further, any of R 1 , R 2 and R 3 may optionally contain at least one —O—, —S—, —CO—, —CO 2 ——, —SO—, —SO 2 —, —NR 4 —, —NR 4 R 5 , —PR 6 —, or —Si(R 7 R 8 )— moiety, wherein R 4 to R 8 are each independently a hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl or aryl group, and may optionally contain at least one —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, amine, phosphorous linkage or silica linkage. It is possible for each of R 1 , R 2 , and R 3 to be the same residue. R 1 , R 2 and R 3 are preferably C 1 to C 12 residues, and more preferably C 1 to C 6 residues, and most preferably a C 1 residue (i.e., methyl). By “alkyl”, “alkenyl”, and “aryl” are also comprehended such residues having substituents, i.e., substituted alkyl, substituted alkenyl and substituted aryl. Each of R 1 , R 2 , and R 3 may be saturated or unsaturated. Saturated residues are preferred.
[0019] Further, X and Y are each independently a hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, aryl group, or may optionally contain one of —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, —NR 9 —, —NR 10 R 11 , —PR 12 —, or —Si(R 13 R 14 )— moiety, wherein R 9 to R 14 is independently a hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, or aryl. Any of R 9 to R 14 may optionally contain at least one —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, amine, phosphorous linkage or silica linkage. It is possible for each of X and Y to be the same residue.
[0020] Substituent Z may be nothing or a direct bond between X and Y, or may be one of —O—, —S—, —CO—, —CO 2 —, —SO—, —SO 2 —, —N(R 15 )—, —NR 16 R 17 , —PR 18 —, —Si(R 19 R 20 )—, or —[C(R 21 ) 2 ] m —, wherein R 15 to R 21 are each independently a hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, or aryl, and m is a number from 1 to 6.
[0021] In a preferred embodiment, the non-aqueous electrolytic solution comprises about 0.01 to about 10 wt %, preferably about 0.05 to about 5 wt % and more preferably about 0.1 to about 3 wt % of one or more nitrogen silylated compounds.
[0022] The electrolytic solutions comprising a nitrogen silylated compound have a low level of residual moisture and acids thereby limiting or reducing decomposition and hydrolysis of the lithium salts, and therefore, of the electrolytic solutions. Preferred embodiments of the invention are described below for the treatment of LiPF 6 based electrolytes but the invention is not limited thereto and may be used with lithium salts in general such as LiBF 4 , LiAsF 6 , LiSbF 6 , LiBOB, LiCF 3 SO 3 , LiN(SO 2 CF 3 ) 2 , and others, as well as combinations of such salts.
[0023] The nitrogen silylated compounds useful herein include:
Combinations of these compounds may also be used.
[0024] Salts. The salts herein are ionic salts containing at least one metal ion. Typically this metal ion is lithium (Li + ). The salts herein function to transfer charge between the anode and the cathode of a battery. One class of salts includes lithium salts that are perhalogenated, or peroxidated, for example, LiPF 6 , LiBF 4 , LiAsF 6 , LiTaF 6 , LiAlCl 4 , Li 2 B 10 Cl 10 , LiClO 4 , LiCF 3 SO 3 , LiN(SO 2 C m F 2m+1 )(SO 2 C n F 2n+1 ), and LiC(SO 2 C k F 2k+1 )(SO 2 C m F 2m+1 )(SO 2 C n F 2n+1 ), wherein k=1-10, m=1-10, and n=1-10, respectively; LiN(SO 2 C p F 2p SO 2 ), and LiC(SO 2 C p F 2p SO 2 )(SO 2 C q F 2q+1 ) wherein p=1-10 and q=1-10; LiPF x (R F ) 6-x , and LiBF y (R F ) 4-y , wherein R F represents perfluorinated C 1 -C 20 alkyl groups or perfluorinated aromatic groups, x=0-5 and y=0-3. Another class of salts useful herein includes lithium salts of chelated orthoborates and chelated orthophosphates (collectively hereinafter, “ortho-salts”), including lithium bis(oxalato)borate (LiBOB), lithium bis(malonato)borate (LiBMB), lithium bis(difluoromalonato)borate (LiBDFMB), lithium (malonato oxalato)borate (LiMOB), lithium (difluoromalonato oxalato)borate (LiDFMOB), lithium tris(oxalato)phosphate (LiTOP), and lithium tris(difluoromalonato)phosphate (LiTDFMP). Any combination of two or more of the aforementioned salts may also be used. Most preferably the salt comprises LiPF 6 .
[0025] Broadly, the concentration of salts in the electrolytic solution is about 0.01-2.5 M (moles per liter). Preferably the total of all salts in the electrolytic solution is about 1 wt % to about 50 wt %, preferably about 3 wt % to about 35 wt % and more preferably about 5 wt % to about 25 wt %.
[0026] Solvent. The solvent is a non-aqueous, aprotic, polar organic substance which dissolves the salt at room temperature, i.e., about 23° C. Blends of more than one solvent may be used. Generally, solvents may be carbonates, carboxylates, lactones, phosphates, five or six member heterocyclic ring compounds, and organic compounds having at least one C 1 -C 4 group connected through an oxygen atom to a carbon. Lactones may be methylated, ethylated and/or propylated. Useful solvents herein include ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, tetrahydrofuran, 2-methyl tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, 1,2-dimethoxyethane, 1,2-diethoxyethane, 1,2-dibutoxyethane, acetonitrile, dimethylformamide, methyl formate, ethyl formate, propyl formate, butyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, butyl butyrate, γ-butyrolactone, 2-methyl-γ-butyrolactone, 3-methyl-γ-butyrolactone, 4-methyl-γ-butyrolactone, β-propiolactone, δ-valerolactone, trimethyl phosphate, triethyl phosphate, tris(2-chloroethyl)phosphate, tris(2,2,2-trifluoroethyl)phosphate, tripropyl phosphate, triisopropyl phosphate, tributyl phosphate, trihexyl phosphate, triphenyl phosphate, tritolyl phosphate, and combinations thereof. Other solvents may be used so long as they are non-aqueous and aprotic, and are capable of dissolving the salts.
[0027] Overall, the non-aqueous electrolytic solution comprises about 20 wt % to about 99 wt %, preferably about 50 wt % to about 97 wt % and more preferably about 70 wt % to about 95 wt % of one or more solvents. In a preferred embodiment, the solvent is selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC) and combinations thereof. In another preferred embodiment, the solvent comprises about 1-60% wt % EC, and about 1-99 wt % DMC, and about 1-99 wt % EMC. In another preferred embodiment, the non-aqueous solvent comprises EC, DMC and EMC in a weight ratio of 1:1:1.
[0028] Cathode. The cathode comprises a lithium metal oxide compound. In particular, the cathode comprises at least one lithium mixed metal oxide (MMO). Lithium MMOs contain at least one other metal selected from the group consisting of Mn, Co, Cr, Fe, Ni, V, and combinations thereof. For example the following lithium MMOs may be used in the cathode: LiMnO 2 , LiMn 2 O 4 , LiCoO 2 , Li 2 Cr 2 O 7 , Li 2 CrO 4 , LiNiO 2 , LiFeO 2 , LiNi z Co 1-z O 2 (0<z<1), LiFePO 4 , Li 3 VPO 4 , LiMn 0.5 Ni 0.5 O 2 , LiMn 1/3 Co 1/3 Ni 1/3 O 2 , LiNi r Co s Me t O 2 wherein Me may be one or more of Al, Mg, Ti, B, Ga, or Si and 0<r,s,t<1, and LiMc 0.5 Mn 1.5 O 4 wherein Mc is a divalent metal, and mixtures thereof.
[0029] Anode. The anode may comprise carbon or compounds of lithium. The carbon may be in the form of graphite. Lithium metal anodes may be used. Lithium MMOs such as LiMnO 2 and Li 4 Ti 5 O 12 are also envisioned. Alloys of lithium with transition or other metals (including metalloids) may be used, including LiAl, LiZn, Li 3 Bi, Li 3 Cd, Li 3 Sd, Li 4 Si, Li 4.4 Pb, Li 4.4 Sn, LiC 6 , Li 3 FeN 2 , Li 2.6 Co 0.4 N, Li 2.6 Cu 0.4 N, and combinations thereof. The anode may further comprise an additional material such as a metal oxide including SnO, SnO 2 , GeO, GeO 2 , In 2 O, In 2 O 3 , PbO, PbO 2 , Pb 2 O 3 , Pb 3 O 4 , Ag 2 O, AgO, Ag 2 O 3 , Sb 2 O 3 , Sb 2 O 4 , Sb 2 O 5 , SiO, ZnO, CoO, NiO, FeO, and combinations thereof.
[0030] Either the anode or the cathode, or both, may further comprise a polymeric binder. In a preferred embodiment, the binder may be polyvinylidene fluoride, styrene-butadiene rubber, polyamide or melamine resin, and combinations thereof.
[0031] The electrolytic solution in the present invention may further comprise one or more additives, such as a vinyl compound (e.g. vinylene carbonate, vinyl ethylene carbonate) to help generate a stable solid electrolyte interface at the surface of the graphite anode so as to increase the cycle life characteristic of the battery, and/or a sultone (e.g., 1,3-propane sultone, and 1,4-butane sultone) to prevent or to reduce gas generation of the electrolytic solution as the battery is charged and discharged at temperatures higher than ambient temperature, and/or an aromatic compound (e.g., biphenyl and cyclohexylbenzene) to prevent overcharge or overdischarge of the battery.
[0032] It is envisioned that the electrolytic solutions and batteries discussed herein have a wide range of applications, including, at least, radios, televisions, calculators, wrist watches, hearing aids, electronics such as computers, cell phones, games etc, and transportation applications such as battery powered and/or hybrid vehicles.
[0033] Examples. The following compositions represent exemplary embodiments of the invention. They are presented to explain the invention in more detail, and do not limit the invention.
[0034] (1) Preparation of the Non-aqueous electrolytic solutions. The starting point for the examples was to blend a solvent mixture of EC/DMC/EMC (1:1:1 by weight) which were commercially available under the Purolyte® name from Ferro Corporation, and then LiPF 6 was added until a non-aqueous electrolytic solution having a LiPF 6 concentration of 1.0 M was obtained. This formed the non-aqueous electrolytic solution used in the Comparative Example. For the Working Examples, the nitrogen silylated compounds in Table 1 were added to obtain a solution with the indicated concentrations in wt % of the overall solution. The blending and testing was carried out at room temperature. A battery using each of these non-aqueous electrolytic solutions was also made.
TABLE 1 Additive type and amount used in 2032 coin cell type batteries. Example Additive Name Additive Amount Example 1 1-Trimethylsilyl-2-pyrrolidinone 0.3 wt % Example 2 3-Trimethylsily-2-oxazolidinone 0.3 wt % Example 3 1-Trimethylsily-1,2,4-triazole 0.3 wt % Example 4 1-Trimethylsilyl pyrrolidine 0.3 wt % Example 5 4-Trimethylsilyl morpholine 0.3 wt % Example 6 3-Trimethylsily-2-oxazolidinone 1.0 wt % Example 7 1-Trimethylsily-1,2,4-triazole 1.0 wt % Example 8 1-Trimethylsilyl pyrrolidine 1.0 wt % Example 9 4-Trimethylsilyl morpholine 1.0 wt % Comparative None None Example
[0035] (2) Preparation of a Cathode. A positive electrode slurry was prepared by dispersing LiCoO 2 (positive electrode active material, 90 wt %), poly(vinylidenefluoride) (PVdF, binder, 5 wt %), and acetylene black (electro-conductive agent, 5 wt %) into 1-methyl-2-pyrrolidone (NMP). The slurry was coated on aluminum foil, dried, and compressed to give a cathode. The cathode was die-cut into discs by a punch with a diameter of 12.7 mm.
[0036] (3) Preparation of an Anode. Artificial graphite (as negative electrode active material, 95 wt %) and PVdF (as binder, 5 wt %) were mixed into NMP to give a negative active material slurry which was coated on copper foil, dried, and pressed to give a negative electrode. The anode electrode was die-cut into discs by a punch with a diameter of 14.3 mm.
[0037] (4) Assembly of a Lithium Ion Secondary Battery. In a dry box under an argon atmosphere, a lithium ion secondary battery was assembled using a 2032 type coin cell. That is, a cathode was placed on a cathode can, and a microporous polypropylene film (25 μm thickness and 19.1 mm diameter) was put thereon as a separator. It was pressed with a polypropylene gasket, and then an anode was placed. A stainless steel spacer and spring were put thereon to adjust a thickness and to make a good contact. An electrolytic solution of the Examples or the Comparative Example was added and let it absorbed inside the battery. Then, an anode cover was mounted thereon to seal the battery by a crimper, thus completing the assembly of the coin type lithium ion secondary battery.
[0038] (5) Testing of the Batteries. Evaluation of the aforementioned assembled batteries (e.g., Working Examples and Comparative Example) was carried out in the order (A) initial charging and discharging (confirmation of capacity) and (B) life cycle test.
[0039] A. Capacity Confirmation. Initial charging and discharging of the aforementioned assembled batteries were performed according to the constant current/voltage charging and constant current discharging method at room temperature. The battery was first charged up to 4.2 Volts (V) at a constant current rate of 0.5 mA/cm 2 (milliamps per square centimeter). After reaching 4.2 V, the battery was continually charged at a constant voltage of 4.2 V until the charging current reached 0.1 mA or less. Then the battery was discharged at a constant current rate of 0.5 mA/cm 2 until the cut-off voltage 3.0 V reached. Standard capacity (C) of a nonaqueous electrolyte secondary battery was 3.4 mAh (milliamp hours).
[0040] B. Life Cycle Test. Life cycle testing was conducted over 100 cycles at room temperature by charging the aforementioned initially charged/discharged batteries at a constant current rate of C/2 (1.7 mA) to 4.2 V and then charged at a constant voltage of 4.2 V till the current reached 0.1 mA or less. After that the battery was discharged at a constant current rate of C/2 (1.7 mA) until the cut-off voltage 3.0 V reached. Discharge capacity retention rate of cycle life (%)=(n th cycle discharge capacity/1 st cycle discharge capacity)×100%. First cycle efficiency is cycle discharge capacity/1st cycle charge capacity×100%. Table 2 displays the results of the life cycle testing.
TABLE 2 Life Cycle Testing Results for 1.0 M LiPF 6 and various methyl nitrogen silylated compounds in EC/DMC/EMC (1:1:1 by weight) Discharge 1 st cycle discharge 1 st cycle capacity retention Example capacity (mAh) efficiency 50 th cycle 100 th cycle Example 1 3.38 91.4% 78.0% — Example 2 3.62 91.7% 88.0% 85.2% Example 3 3.55 91.3% 84.0% 75.6% Example 4 3.56 94.1% 90.1% 84.8% Example 5 3.53 94.6% 94.9% 92.5% Example 6 3.55 89.3% 76.7% — Example 7 3.50 90.6% 86.8% 82.0% Example 8 3.42 91.5% 87.2% 87.2% Example 9 3.39 91.7% 88.7% 88.1% Comparative 3.38 94.5% 82.0% 80.4% Example
[0041] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and illustrative example shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general invention concept as defined by the appended claims and their equivalents. | The invention relates to the use of a nitrogen silylated compound as additive in a nonaqueous electrolytic solution. The electrolytic solution is suitable for use in electrochemical cells such as lithium and lithium ion batteries. Batteries using this electrolytic solution have long cycle life and high capacity retention. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. patent application Ser. No. 12/289,959 filed on Nov. 7, 2008, which is a divisional of U.S. patent application Ser. No. 11/125,098, filed on May 10, 2005, which is a divisional of U.S. patent application Ser. No. 10/368,351, filed on Feb. 20, 2003, which is a Continuation-in-Part of U.S. patent application Ser. No. 10/305,979, filed Nov. 29, 2002 the disclosures of which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
1. Field of Invention
The invention relates to an ink-jet head for printing by ejecting ink onto a print medium, and to an ink-jet printer having the ink-jet head.
2. Description of Related Art
In an ink-jet printer, an ink-jet head distributes ink supplied from an ink tank to pressure chambers. The ink-jet head selectively applies pressure to each pressure chamber to eject ink through a nozzle. As a means for selectively applying pressure to the pressure chambers, an actuator unit may be used in which ceramic piezoelectric sheets are laminated.
As an example, a generally known ink-jet head has one actuator unit in which continuous flat piezoelectric sheets extending over a plurality of pressure chambers are laminated. At least one of the piezoelectric sheets is sandwiched by a common electrode which is common to many pressure chambers and is being kept at the ground potential, and many individual electrodes, i.e., driving electrodes, disposed at positions corresponding to the respective pressure chambers. When a individual electrode on one face of the sheet is set at a potential different from that of the common electrode on the other face, the part of piezoelectric sheet being sandwiched by the individual and common electrodes and polarized in its thickness, is expanded or contracted in its thickness direction as an active layer by the so-called longitudinal piezoelectric effect. This causes the volume of the corresponding pressure chamber to change, so that the ink can be ejected toward a print medium through a nozzle communicating with the pressure chamber.
In the above-described ink-jet head, to ensure good ink ejection performance, the actuator unit must be accurately positioned to a passage unit so that the individual electrodes must be at predetermined positions corresponding to the respective pressure chambers in a plan view.
Generally, in an ink-jet head such as the one described above, the passage unit in which ink passages including pressure chambers have been formed is manufactured separately from the actuator unit. The passage unit is then bonded with an adhesive to the actuator unit so that the pressure chambers are close to the actuator unit. This bonding process is done by matching a mark formed on the passage unit against a mark formed on the actuator unit.
Generally, the piezoelectric sheets of the actuator unit are manufactured through a sintering process while the passage unit is laminated with metallic sheets. Therefore, as the size of the piezoelectric sheets increases, the positional accuracy of the electrodes decreases. Thus, the longer the head is, the more difficult the positioning process is between the pressure chambers in the passage unit and the individual electrodes in the actuator unit. As a result, the manufacturing yield for the printer heads is reduced.
Furthermore, because the actuator unit it is made of ceramic, it is an expensive and very brittle component. In particular, in the actuator unit having a polygonal shape, the corners can easily brake. The breakage loss causes the manufacture cost to increase. Further, the actuator unit requires very delicate handling to ensure that a corner does not collide against another component. This makes the ink-jet head assembling difficult.
SUMMARY OF THE INVENTION
An objective of the invention is to provide an ink-jet head in which an actuator unit has been accurately positioned relative to a passage unit.
Another objective of the invention is to provide an ink-jet head having an actuator unit that is difficult to brake.
According to one aspect of the invention, a printhead module includes a plurality of rows of printhead nozzles, at least some of the rows including at least one displaced row portion, the displacement of the row portion including a component in a direction normal to that of a pagewidth to be printed, wherein the displaced row portions of at least some of the rows are different in length than the displaced row portions of at least some of the other rows.
BRIEF DESCRIPTION OF THE DRAWINGS
Various exemplary embodiments of the invention will be described in detail with reference to the following figures, in which:
FIG. 1 is a general view of an ink-jet printer including ink-jet heads according to a first exemplary embodiment of the invention;
FIG. 2 is a perspective view of an ink-jet head according to a first embodiment of the invention;
FIG. 3 is a sectional view taken along line III-III in FIG. 2 ;
FIG. 4 is a plan view of a head main body included in the ink-jet head of FIG. 2 ;
FIG. 5 is an enlarged view of the region enclosed with an alternate long and short dash line in FIG. 4 ;
FIG. 6 is an enlarged view of the region enclosed with an alternate long and short dash line in FIG. 5 ;
FIG. 7 is a partial sectional view of the head main body of FIG. 4 ;
FIG. 8 is an enlarged view of the region enclosed with an alternate long and two short dashes line in FIG. 5 ;
FIG. 9 is a partial exploded view of the head main body of FIG. 4 ;
FIG. 10 is an enlarged sectional view when laterally viewing the region enclosed with an alternate long and short dash line in FIG. 7 ;
FIG. 11 is a plan view of a head main body included in an ink-jet head according to a second exemplary embodiment of the invention;
FIG. 12 is a bottom view of the head main body of FIG. 11 ;
FIG. 13 is a cross-sectional view of the head main body of FIG. 11 ;
FIG. 14 is an enlarged view of the region Q enclosed with an alternate long and short dash line in FIG. 13 ;
FIG. 15 is a partial sectional view of the head main body of FIG. 11 ;
FIG. 16 is an enlarged sectional view illustrating the detailed construction of an actuator unit in the head main body of FIG. 11 ;
FIG. 17 is an enlarged plan view of an actuator unit in the head main body of FIG. 11 ;
FIG. 18 is an enlarged plan view showing a seam portion between two actuator units of FIG. 17 ;
FIG. 19 is an enlarged plan view of an actuator unit according to a modification of a second exemplary embodiment of the invention;
FIG. 20 is an enlarged plan view showing a seam portion between two actuator units of FIG. 19 ;
FIG. 21A is a plan view of a head main body included in an ink-jet head according to a modification of the invention, in which four actuator units are arranged;
FIG. 21B is a plan view of a head main body included in an ink-jet head according to another modification of the invention, in which four actuator units are arranged;
FIG. 22 is a plan view of a head main body included in an ink-jet head according to a third exemplary embodiment of the invention;
FIG. 23 is a bottom view of the head main body of FIG. 22 ;
FIG. 24 is a cross-sectional view of the head main body of FIG. 22 ;
FIG. 25 is an enlarged view of the region E enclosed with an alternate long and short dash line in FIG. 24 ;
FIG. 26 is a partial sectional view of the head main body of FIG. 22 ;
FIG. 27 is an enlarged sectional view illustrating the detailed construction of an actuator unit in the head main body of FIG. 22 ;
FIG. 28A is a schematic view illustrating the profile of an actuator unit included in the head main body of FIG. 22 ;
FIG. 28B is a schematic view illustrating the profile of an actuator unit as a modification;
FIG. 29A is a plan view of a modification of the head main body of FIG. 22 , which includes heptagonal actuator units;
FIG. 29B is a plan view of an actuator unit included in the head main body of FIG. 29A ;
FIG. 30A is a plan view of another modification of the head main body of FIG. 22 , which includes octagonal actuator units;
FIG. 30B is a plan view of an actuator unit included in the head main body of FIG. 30A ;
FIG. 31A is a plan view of still another modification of the head main body of FIG. 22 , which includes partially rounded actuator units;
FIG. 31B is a plan view of an actuator unit included in the head main body of FIG. 31A ; and
FIG. 32 is a schematic view of a principal part of an ink-jet printer according to the fourth exemplary embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 1 to 10 , an ink-jet head will be described as a reference for understanding ink-jet heads according to various exemplary embodiments of the invention. FIG. 1 is a general view of an ink-jet printer having ink-jet heads according to a first exemplary embodiment of the invention. The ink-jet printer 101 shown in FIG. 1 is a color ink-jet printer having four ink-jet heads 1 . In this printer 101 , an image recording medium feed unit 111 and an image recording medium discharge unit 112 are disposed in left and right portions of FIG. 1 , respectively.
In the printer 101 , an image recording medium transfer path is provided extending from the image recording medium feed unit 111 to the image recording medium discharge unit 112 . A pair of feed rollers 105 a and 105 b is disposed immediately downstream of the image recording medium feed unit 111 for pinching and advancing an image record medium sheet, such as a paper. In various exemplary embodiments, the image recording medium includes, for example, a sheet of paper, card stock, photo paper, a transparency, or the like.
The image recording medium is transferred by the pair of feed rollers 105 a and 105 b from the left to the right in FIG. 1 . In the middle of the image recording medium transfer path, two belt rollers 106 and 107 and an endless transfer belt 108 are disposed. The transfer belt 108 is wound on the belt rollers 106 and 107 to extend between them. The outer face, i.e., the transfer face, of the transfer belt 108 has been treated with silicone or like material. Thus, an image recording medium fed through the pair of feed rollers 105 a and 105 b can be held on the transfer face of the transfer belt 108 by the adhesion of the silicone treated face. In this state, the image recording medium is transferred downstream (rightward) by driving one belt roller 106 to rotate clockwise in FIG. 1 (the direction indicated by an arrow 104 ).
Pressing members 109 a and 109 b are disposed at positions for feeding an image recording medium onto the belt roller 107 and taking out the image recording medium from the belt roller 106 , respectively. Either of the pressing members 109 a and 109 b can be for pressing the image recording medium onto the transfer face of the transfer belt 108 so as to prevent the image recording medium from separating from the transfer face of the transfer belt 108 . Thus, the image recording medium securely adheres to the transfer face.
A peeling device 110 is provided immediately downstream of the transfer belt 108 along the image recording medium transfer path. The peeling device 110 peels off the image recording medium, which has adhered to the transfer face of the transfer belt 108 , from the transfer face to transfer the image recording medium toward the rightward image recording medium discharge unit 112 .
Each of the four ink-jet heads 1 has, at its lower end, a head main body 1 a . Each head main body 1 a has a rectangular section. The head main bodies 1 a are arranged close to each other with the longitudinal axis of each head main body 1 a being perpendicular to the image recording medium transfer direction (perpendicular to FIG. 1 ). That is, this printer 101 is a line type printer. The bottom of each of the four head main bodies 1 a faces the image recording medium transfer path. In the bottom of each head main body 1 a , a number of nozzles are provided, each having a small-diameter ink ejection port. The four head main bodies 1 a eject ink of magenta, yellow, cyan, and black, respectively. However, various other embodiments of the invention are not limited by the above described colors or order.
The head main bodies 1 a are disposed such that a narrow clearance must be formed between the lower face of each head main body 1 a and the transfer face of the transfer belt 108 . The image recording medium transfer path is formed within the narrow clearance. In this construction, while an image recording medium that is being transferred by the transfer belt 108 passes immediately below the four head main bodies 1 a in order, the inks are ejected through the corresponding nozzles toward the upper face, i.e., the print face, of the image recording medium to form a desired color image on the image recording medium.
The ink-jet printer 101 is provided with a maintenance unit 117 for automatically carrying out maintenance of the ink-jet heads 1 . The maintenance unit 117 includes four caps 116 for covering the lower faces of the four head main bodies 1 a , and a purge system (not shown).
During ink-jet printer 101 operation, the maintenance unit 117 is at a position immediately below the image recording medium feed unit 117 (withdrawal position). When a predetermined condition is satisfied after finishing the printing operation (for example, when a state in which no printing operation is performed continues for a predetermined time period or when the printer 101 is powered off), the maintenance unit 117 moves to a position (cap position) immediately below the four head main bodies 1 a . At this cap position, the maintenance unit 117 covers the lower faces of the head main bodies 1 a with the respective caps 116 to prevent ink in the nozzles from becoming dry.
The belt rollers 106 and 107 and the transfer belt 108 are supported by a chassis 113 . The chassis 113 is put on a cylindrical member 115 disposed under the chassis 113 . The cylindrical member 115 is rotatable around a shaft 114 provided at an off center position of the cylindrical member 115 . Thus, by rotating the shaft 114 , the level of the uppermost portion of the cylindrical member 115 can be changed to move up or down the chassis 113 accordingly. When the maintenance unit 117 is moved from the withdrawal position to the cap position, the cylindrical member 115 must have been rotated at a predetermined angle in advance so as to move down the transfer belt 108 and the belt rollers 106 and 107 by an applicable distance from the position illustrated in FIG. 1 . A space for the movement of the maintenance unit 117 is thereby ensured.
In the region surrounded by the transfer belt 108 , a nearly rectangular global change guide 121 (having its width substantially equal to that of the transfer belt 108 ) is disposed at an opposite position to the ink-jet heads 1 . The guide 121 is in contact with the lower face of the upper part of the transfer belt 108 to support the upper part of the transfer belt 108 from the inside.
With reference to FIGS. 2 and 3 , the construction of each ink-jet head 1 according to this embodiment will be described in more detail. The ink-jet head 1 according to this embodiment includes a head main body 1 a having a rectangular shape in a plan view and extending in a main scanning direction, and a base portion 131 for supporting the head main body 1 a . The base portion 131 further supports driver ICs 132 for supplying driving signals to individual electrodes 35 a and 35 b (shown in FIG. 6 and FIG. 10 ), and substrates 133 .
Referring to FIG. 2 , the base portion 131 includes a base block 138 partially bonded to the upper face of the head main body 1 a to support the head main body 1 a , and a holder 139 bonded to the upper face of the base block 138 to support the base block 138 . The base block 138 is a nearly rectangular member having substantially the same length of the head main body 1 a . The base block 138 is made of metal material such as stainless steel and functions as a light structure for reinforcing the holder 139 . The holder 139 includes a holder main body 141 disposed near the head main body 1 a , and a pair of holder support portions 142 each extending on the opposite side of the holder main body 141 to the head main body 1 a . Each holder support portion 142 is configured as a flat member. The holder support portions 142 extend along the longitudinal direction of the holder main body 141 and are disposed in parallel with each other at a predetermined interval.
Skirt portions 141 a in a pair, protruding downward, are provided in both end portions of the holder main body 141 a in a direction perpendicular to the main scanning direction. Each skirt portion 141 a is formed through the length of the holder main body 141 . As a result, in the lower portion of the holder main body 141 , a nearly rectangular groove 141 b is defined by the pair of skirt portions 141 a . The base block 138 is received in the groove 141 b . The upper surface of the base block 138 is bonded to the bottom of the groove 141 b of the holder main body 141 with an adhesive. The thickness of the base block 138 is slightly larger than the depth of the groove 141 b of the holder main body 141 . As a result, the lower end of the base block 138 protrudes downward beyond the skirt portions 141 a.
Within the base block 138 , as a passage for ink to be supplied to the head main body 1 a , an ink reservoir 3 is formed as a nearly rectangular space or hollow region extending along the longitudinal direction of the base block 138 . Openings 3 b (see FIG. 4 ) are formed in the lower face 145 of the base block 138 , each communicating with the ink reservoir 3 . The ink reservoir 3 is connected with a not-illustrated main ink tank or ink supply source through a supply tube (not shown) within the printer main body. Thus, the ink reservoir 3 is appropriately supplied with ink from the main ink tank.
In the lower face 145 of the base block 138 , the surrounding of each opening 3 b protrudes downward from the surrounding portion. The base block 138 is in contact with a passage unit 4 (see FIG. 3 ) of the head main body 1 a at the only vicinity portion 145 a of each opening 3 b of the lower face 145 . Thus, the region of the lower face 145 of the base block 138 other than the vicinity portion 145 a of each opening 3 b is distant from the head main body 1 a . Actuator units 21 are disposed within the distance.
To the outer side face of each holder support portion 142 of the holder 139 , a driver IC 132 is attached with an elastic member 137 such as a sponge being interposed between them. A heat sink 134 is disposed in close contact with the outer side face of the driver IC 132 . The heat sink 134 is made of a nearly rectangular member for efficiently radiating heat generated in the driver IC 132 . A flexible printed circuit (FPC) 136 , which acts as a power supply member, is connected to the driver IC 132 . The FPC 136 connected with the driver IC 132 is bonded to, and electrically connected with, the corresponding substrate 133 and the head main body 1 a by soldering. The substrate 133 is disposed outside the FPC 136 above the driver IC 132 and the heat sink 134 . The upper face of the heat sink 134 is bonded to the substrate 133 with a seal member 149 . The lower face of the heat sink 134 is also bonded to the FPC 136 with a seal member 149 .
A seal member 150 is disposed between the lower face of each skirt portion 141 a of the holder main body 141 and the upper face of the passage unit 4 , to sandwich the FPC 136 . The FPC 136 is fixed to the passage unit 4 and the holder main body 141 by the seal member 150 . Therefore, even if the head main body 1 a is elongated, the head main body 1 a can be prevented from bending, the interconnecting portion between each actuator unit and the FPC 136 can be prevented from being stressed, and the FPC 136 can be securely held in place.
Referring to FIG. 2 , near each lower corner of the ink-jet head 1 along the main scanning direction, six protruding portions 30 a are disposed at regular intervals along the corresponding side wall of the ink-jet head 1 . These protruding portions 30 a are provided at both ends in the sub scanning direction of a nozzle plate 30 in the lowermost layer of the head main body 1 a (see FIGS. 7A and 7B ). The nozzle plate 30 is bent by about 90 degrees along the boundary line between each protruding portion 30 a and the other portion. The protruding portions 30 a are provided at positions corresponding to the vicinities of both ends of various image recording mediums to be used for printing. Each bent portion of the nozzle plate 30 has a shape not right-angled but rounded. This configuration makes it difficult for an image recording medium to jam, which typically occurs in known devices because the leading edge of the image recording medium, which has been transferred to approach the head 1 , is stopped by the side face of the head 1 .
FIG. 4 is a schematic plan view of the head main body 1 a . In FIG. 4 , an ink reservoir 3 formed in the base block 138 is conceptually illustrated with a broken line. Referring to FIG. 4 , the head main body 1 a has a rectangular shape in the plan view extending in the main scanning direction. The head main body 1 a includes a passage unit 4 in which a large number of pressure chambers 10 and a large number of ink ejection ports 8 at the front ends of nozzles (see FIGS. 5 , 6 , and 7 ), are formed as described later. Trapezoidal actuator units 21 arranged in two lines in a crisscross manner are bonded onto the upper face of the passage unit 4 . Each actuator unit 21 is disposed such that its parallel opposed sides (upper and lower sides) extend along the longitudinal direction of the passage unit 4 . The oblique sides of each neighboring actuator units 21 overlap each other in the lateral direction of the passage unit 4 .
The lower face of the passage unit 4 corresponding to the bonded region of each actuator unit 4 is made into an ink ejection region. In the surface of each ink ejection region, a large number of ink ejection ports 8 are arranged in a matrix, as described later. In the base block 138 disposed above the passage unit 4 , an ink reservoir 3 is formed along the longitudinal direction of the base block 138 . The ink reservoir 3 communicates with an ink tank (not shown) through an opening 3 a provided at one end of the ink reservoir 3 , so that the ink reservoir 3 is always filled up with ink. In the ink reservoir 3 , pairs of openings 3 h are provided in regions where no actuator unit 21 is present, so as to be arranged in a crisscross manner along the longitudinal direction of the ink reservoir 3 .
FIG. 5 is an enlarged view of the region enclosed with an alternate long and short dash line in FIG. 4 . Referring to FIGS. 4 and 5 , the ink reservoir 3 communicates through each opening 3 b with a manifold channel 5 disposed under the opening 3 b . Each opening 3 b is provided with a filter (not shown) for catching dust and dirt contained in ink. The front end portion of each manifold channel 5 branches into two sub-manifold channels 5 a . Below each single actuator unit 21 , two sub-manifold channels 5 a extend from each of the two openings 3 b on both sides of the actuator unit 21 in the longitudinal direction of the ink-jet head 1 . That is, below the single actuator unit 21 , four sub-manifold channels 5 a in total extend along the longitudinal direction of the ink-jet head 1 . Each sub-manifold channel 5 a is filled up with ink supplied from the ink reservoir 3 .
FIG. 6 is an enlarged view of the region enclosed with an alternate long and short dash line in FIG. 5 . Referring to FIGS. 5 and 6 , on the upper face of each actuator unit 21 , individual electrodes 35 a , each having a nearly rhombic shape in a plan view, are regularly arranged in a matrix. In addition, individual electrodes 35 b having the same shape as the individual electrodes 35 a are disposed in the actuator unit 21 to vertically overlap the respective individual electrodes 35 a . A large number of ink ejection ports 8 are regularly arranged in a matrix in the surface of the ink ejection region corresponding to the actuator unit 21 of the passage unit 4 . In the passage unit 4 , pressure chambers (cavities) 10 , each having a nearly rhombic shape in a plan view but somewhat larger than that of the individual electrodes 35 a and 35 b , are regularly arranged in a matrix. In the passage unit 4 , apertures 12 are also regularly arranged in a matrix. These pressure chambers 10 and apertures 12 communicate with the corresponding ink ejection ports 8 . The pressure chambers 10 are provided at positions corresponding to the respective individual electrodes 35 a and 35 b . In a plan view, the large part of the individual electrode 35 a and 35 b is included in a region of the corresponding pressure chamber 10 . In FIGS. 5 and 6 , for ease of understanding, the pressure chambers 10 , the apertures 12 , etc., are illustrated with solid lines, although they should be illustrated with broken lines because they are within the actuator unit 21 or the passage unit 4 .
FIG. 7 is a partial sectional view of the head main body 1 a of FIG. 4 along the longitudinal direction of a pressure chamber. As shown in FIG. 7 , each ink ejection port 8 is formed at the front end of a tapered nozzle. Each ink ejection port 8 communicates with a sub-manifold channel 5 a through a pressure chamber 10 (length: 900 μm, width: 350 μm) and an aperture 12 . Thus, within the ink-jet head 1 , ink passages 32 , each extending from an ink tank to an ink ejection port 8 through an ink reservoir 3 , a manifold channel 5 , a sub-manifold channel 5 a , an aperture 12 , and a pressure chamber 10 are formed.
Referring to FIG. 7 , the pressure chamber 10 and the aperture 12 are provided at different levels. Therefore, in the portion of the passage unit 4 corresponding to the ink ejection region under an actuator unit 21 , an aperture 12 communicating with one pressure chamber 10 can be disposed within the same portion in plan view as a pressure chamber 10 neighboring the pressure chamber 10 communicating with the aperture 12 . As a result, because the pressure chambers 10 can be arranged close to each other at a high density, high resolution image printing can be achieved with an ink-jet head 1 having a relatively small work area.
In the plane of FIGS. 5 and 6 , pressure chambers 10 are arranged within an ink ejection region in two directions, i.e., a direction along the longitudinal direction of the ink-jet head 1 (first arrangement direction) and a direction somewhat inclining from the lateral direction of the ink-jet head 1 (second arrangement direction). The first and second arrangement directions form an angle theta θ somewhat smaller than the right angle. The ink ejection ports 8 are arranged at 50 dpi in the first arrangement direction. On the other hand, the pressure chambers 10 are arranged in the second arrangement direction such that the ink ejection region corresponding to one actuator unit 21 include twelve pressure chambers 10 . Therefore, within the whole width of the ink-jet head 1 , in a region of the interval between two ink ejection ports 8 neighboring each other in the first arrangement direction, there are twelve ink ejection ports 8 . At both ends of each ink ejection region in the first arrangement direction (corresponding to an oblique side of the actuator unit 21 ), the above condition is satisfied by making a compensation relation to the ink ejection region corresponding to the opposite actuator unit 21 in the lateral direction of the ink-jet head 1 . Therefore, in the ink-jet head 1 , by ejecting ink droplets in order through a large number of ink ejection ports 8 arranged in the first and second directions with relative movement of an image recording medium along the lateral direction of the ink-jet head 1 , printing at 600 dpi in the main scanning direction can be performed.
Next, the construction of the passage unit 4 will be described in more detail with reference to FIG. 8 . FIG. 8 is a schematic view showing the positional relation among each pressure chamber 10 , each ink ejection port 8 , and each aperture (restricted passage) 12 . Referring to FIG. 8 , pressure chambers 10 are arranged in lines in the first arrangement direction at predetermined intervals at 50 dpi. Twelve lines of pressure chambers 10 are arranged in the second arrangement direction. As the whole, the pressure chambers 10 are two-dimensionally arranged in the ink ejection region corresponding to one actuator unit 21 .
The pressure chambers 10 are classified into two types, i.e., pressure chambers 10 a , in each of which a nozzle is connected with the upper acute portion in FIG. 8 , and pressure chambers 10 b , in each of which a nozzle is connected with the lower acute portion. Pressure chambers 10 a and 10 b are arranged in the first arrangement direction to form pressure chamber lines 11 a and 11 b , respectively. Referring to FIG. 8 , in the ink ejection region corresponding to one actuator unit 21 , from the lower side of FIG. 8 , there are disposed two pressure chamber lines 11 a and two pressure chamber lines 11 b neighboring the upper side of the pressure chamber lines 11 a . The four pressure chamber lines of the two pressure chamber lines 11 a and the two pressure chamber lines 11 b constitute a set of pressure chamber lines. Such a set of pressure chamber lines is repeatedly disposed three times from the lower side in the ink ejection region corresponding to one actuator unit 21 . A straight line extending through the upper acute portion of each pressure chamber in each pressure chamber lines 11 a and 11 b crosses the lower oblique side of each pressure chamber in the pressure chamber line neighboring the upper side of that pressure chamber line.
As described above, when viewing perpendicularly to FIG. 8 , two first pressure chamber lines 11 a and two pressure chamber lines 11 b , in which nozzles connected with pressure chambers 10 are disposed at different positions, are arranged alternately to neighbor each other. Consequently, as the whole, the pressure chambers 10 are arranged regularly. On the other hand, nozzles are arranged in a concentrated manner in a central region of each set of pressure chamber lines constituted by the above four pressure chamber lines. Therefore, in case that each four pressure chamber lines constitute a set of pressure chamber lines and such a set of pressure chamber lines is repeatedly disposed three times from the lower side as described above, there is formed a region where no nozzle exists, in the vicinity of the boundary between each neighboring sets of pressure chamber lines, i.e., on both sides of each set of pressure chamber lines constituted by four pressure chamber lines. Wide sub-manifold channels 5 a extend there for supplying ink to the corresponding pressure chambers 10 . In this ink-jet head, in the ink ejection region corresponding to one actuator unit 21 , four wide sub-manifold channels 5 a in total are arranged in the first arrangement direction, i.e., one on the lower side of FIG. 8 , one between the lowermost set of pressure chamber lines and the second lowermost set of pressure chamber lines, and two on both sides of the uppermost set of pressure chamber lines.
Referring to FIG. 8 , nozzles communicating with ink ejection ports 8 for ejecting ink are arranged in the first arrangement direction at regular intervals at 50 dpi to correspond to the respective pressure chambers 10 regularly arranged in the first arrangement direction. On the other hand, while twelve pressure chambers 10 are regularly arranged also in the second arrangement direction forming an angle θ with the first arrangement direction, twelve nozzles corresponding to the twelve pressure chambers 10 include ones each communicating with the upper acute portion of the corresponding pressure chamber 10 and ones each communicating with the lower acute portion of the corresponding pressure chamber 10 , as a result, they are not regularly arranged in the second arrangement direction at regular intervals.
If all nozzles communicate with the same-side acute portions of the respective pressure chambers 10 , the nozzles are regularly arranged also in the second arrangement direction at regular intervals. In this case, nozzles are arranged so as to shift in the first arrangement direction by a distance corresponding to 600 dpi printing resolution per pressure chamber line from the lower side to the upper side of FIG. 8 . Contrastively in this ink-jet head, because four pressure chamber lines of two pressure chamber lines 11 a and two pressure chamber lines 11 b constitute a set of pressure chamber lines and such a set of pressure chamber lines is repeatedly disposed three times from the lower side, the shift of nozzle position in the first arrangement direction per pressure chamber line from the lower side to the upper side of FIG. 8 is not always the same.
In the ink-jet head 1 , a band region R will be discussed that has a width (about 508.0 μm) corresponding to 50 dpi in the first arrangement direction and extends perpendicularly to the first arrangement direction. In this band region R, any of twelve pressure chamber lines includes only one nozzle. That is, when such a band region R is defined at an optional position in the ink ejection region corresponding to one actuator unit 21 , twelve nozzles are always distributed in the band region R. The positions of points respectively obtained by projecting the twelve nozzles onto a straight line extending in the first arrangement direction are distant from each other by a distance corresponding to a 600 dpi printing resolution.
When the twelve nozzles included in one band region R are denoted by ( 1 ) to ( 12 ) in order from one whose projected image onto a straight line extending in the first arrangement direction is the leftmost, the twelve nozzles are arranged in the order of ( 1 ), ( 7 ), ( 2 ), ( 8 ), ( 5 ), ( 11 ), ( 6 ), ( 12 ), ( 9 ), ( 3 ), ( 10 ), and ( 4 ) from the lower side.
In the thus-constructed ink-jet head 1 , by properly driving active layers in the actuator unit 21 , a character, an figure, or the like, having a resolution of 600 dpi can be formed. That is, by selectively driving active layers corresponding to the twelve pressure chamber lines in order in accordance with the transfer of a print medium, a specific character or figure can be printed on the image recording medium.
By way of example, a case will be described wherein a straight line extending in the first arrangement direction is printed at a resolution of 600 dpi. First, a case will be briefly described wherein nozzles communicate with the same-side acute portions of pressure chambers 10 . In this case, in accordance with transfer of an image recording medium, ink ejection starts from a nozzle in the lowermost pressure chamber line in FIG. 8 . Ink ejection is then shifted upward with selecting a nozzle belonging to the upper neighboring pressure chamber line in order. Ink dots are thereby formed in order in the first arrangement direction with neighboring each other at 600 dpi. Finally, all the ink dots form a straight line extending in the first arrangement direction at a resolution of 600 dpi.
On the other hand, in this ink-jet head, ink ejection starts from a nozzle in the lowermost pressure chamber line 11 a in FIG. 8 , and ink ejection is then shifted upward with selecting a nozzle communicating with the upper neighboring pressure chamber line in order in accordance with transfer of a print medium. In this embodiment, however, because the positional shift of nozzles in the first arrangement direction per pressure chamber line from the lower side to the upper side is not always the same, ink dots formed in order in the first arrangement direction in accordance with the transfer of the print medium are not arranged at regular intervals at 600 dpi.
More specifically, as shown in FIG. 8 , in accordance with the transfer of the print medium, ink is first ejected through a nozzle ( 1 ) communicating with the lowermost pressure chamber line 11 a in FIG. 8 to form a dot row on the print medium at intervals corresponding to 50 dpi (about 508.0 μm). Next, as the print medium is transferred and the straight line formation position has reached the position of a nozzle ( 7 ) communicating with the second lowermost pressure chamber line 11 a , ink is ejected through the nozzle ( 7 ). The second ink dot is thereby formed at a position shifted from the first formed dot position in the first arrangement direction by a distance of six times the interval corresponding to 600 dpi (about 42.3 μm) (about 42.3 μm×6=about 254.0 μm).
Next, as the print medium is further transferred and the straight line formation position has reached the position of a nozzle ( 2 ) communicating with the third lowermost pressure chamber line 11 b , ink is ejected through the nozzle ( 2 ). The third ink dot is thereby formed at a position shifted from the first formed dot position in the first arrangement direction by a distance of the interval corresponding to 600 dpi (about 42.3 μm). As the print medium is further transferred and the straight line formation position has reached the position of a nozzle ( 8 ) communicating with the fourth lowermost pressure chamber line 11 b , ink is ejected through the nozzle ( 8 ). The fourth ink dot is thereby formed at a position shifted from the first formed dot position in the first arrangement direction by a distance of seven times the interval corresponding to 600 dpi (about 42.3 μm) (about 42.3 μm×7=about 296.3 μm). As the print medium is further transferred and the straight line formation position has reached the position of a nozzle ( 5 ) communicating with the fifth lowermost pressure chamber line 11 a , ink is ejected through the nozzle ( 5 ). The fifth ink dot is thereby formed at a position shifted from the first formed dot position in the first arrangement direction by a distance of four times the interval corresponding to 600 dpi (about 42.3 μm) (about 42.3 μm×4=about 169.3 μm).
After this, in the same manner, ink dots are formed with selecting nozzles communicating with pressure chambers 10 in order from the lower side to the upper side in FIG. 8 . In this case, when the number of a nozzle in FIG. 8 is N, an ink dot is formed at a position shifted from the first formed dot position in the first arrangement direction by a distance corresponding to (magnification n=N−1)×(interval corresponding to 600 dpi). When the twelve nozzles have been finally selected, the gap between the ink dots to be formed by the nozzles ( 1 ) in the lowermost pressure chamber lines 11 a in FIG. 8 at an interval corresponding to 50 dpi (about 508.0 μm) is filled up with eleven dots formed at intervals corresponding to 600 dpi (about 42.3 μm). Therefore, as the whole, a straight line extending in the first arrangement direction can be drawn at a resolution of 600 dpi.
Next, the sectional construction of the ink-jet head 1 will be described. FIG. 9 is a partial exploded view of the head main body 1 a of FIG. 4 . FIG. 10 is an enlarged sectional view when laterally viewing the region enclosed with an alternate long and short dash line in FIG. 7 . Referring to FIGS. 7 and 9 , a principal portion on the bottom side of the ink-jet head 1 has a layered structure laminated with ten sheet materials in total, i.e., from the top, an actuator unit 21 , a cavity plate 22 , a base plate 23 , an aperture plate 24 , a supply plate 25 , manifold plates 26 , 27 , and 28 , a cover plate 29 , and a nozzle plate 30 . Of them, nine plates other than the actuator unit 21 constitute a passage unit 4 .
As described later in detail, the actuator unit 21 is laminated with five piezoelectric sheets 41 to 45 (see FIG. 10 ) and is provided with electrodes so that only the uppermost layer and the second layer neighboring the uppermost layer include portions to be active when an electric field is applied (hereinafter, simply referred to as “layer including active layers (active portions)”) and the remaining three layers are inactive. The cavity plate 22 is made of metal, in which a large number of substantially rhombic openings are formed corresponding to the respective pressure chambers 10 . The base plate 23 is made of metal, in which a communication hole between each pressure chamber 10 of the cavity plate 22 and the corresponding aperture 12 , and a communication hole between the pressure chamber 10 and the corresponding ink ejection port 8 are formed. The aperture plate 24 is made of metal, in which, in addition to apertures 12 , communication holes are formed for connecting each pressure chamber 10 of the cavity plate 22 with the corresponding ink ejection port 8 . The supply plate 25 is made of metal, in which communication holes between each aperture 12 and the corresponding sub-manifold channel 5 a and communication holes for connecting each pressure chamber 10 of the cavity plate 22 with the corresponding ink ejection port 8 are formed. Each of the manifold plates 26 , 27 , and 28 is made of metal, which defines an upper portion of each sub-manifold channel 5 a and in which communication holes are formed for connecting each pressure chamber 10 of the cavity plate 22 with the corresponding ink ejection port 8 . The cover plate 29 is made of metal, in which communication holes are formed for connecting each pressure chamber 10 of the cavity plate 22 with the corresponding ink ejection port 8 . The nozzle plate 30 is made of metal, in which tapered ink ejection ports 8 each functioning as a nozzle are formed for the respective pressure chambers 10 of the cavity plate 22 .
Sheets 21 to 30 are positioned in layers with each other to form such an ink passage 32 as illustrated in FIG. 6 . The ink passage 32 first extends upward from the sub-manifold channel 5 a , then extends horizontally in the aperture 12 , then further extends upward, then again extends horizontally in the pressure chamber 10 , then extends obliquely downward in a certain length away from the aperture 12 , and then extends vertically downward toward the ink ejection port 8 .
Referring to FIG. 10 , the actuator unit 21 includes five piezoelectric sheets 41 , 42 , 43 , 44 , and 45 having the same thickness of about 15 μm. These piezoelectric sheets 41 to 45 are made into a continuous layered flat plate (continuous flat layers) that is disposed so as to extend over many pressure chambers 10 formed within one ink ejection region in the ink-jet head 1 . Because the piezoelectric sheets 41 to 45 are disposed so as to extend over many pressure chambers 10 as continuous flat layers, the individual electrodes 35 a and 35 b can also be arranged at a high density by using, e.g., a screen printing technique. Therefore, the pressure chambers 10 formed at positions corresponding to the individual electrodes 35 a and 35 b can also be arranged at a high density. This makes it possible to print a high-resolution image. In this embodiment, each of the piezoelectric sheets 41 to 45 is made of a lead zirconate titanate (PZT)-base ceramic material having ferroelectricity.
Between the uppermost piezoelectric sheet 41 and the piezoelectric sheet 42 neighboring downward the piezoelectric sheet 41 , an about 2 micron-thick common electrode 34 a is interposed formed on the whole of the lower and upper faces of the piezoelectric sheets. Also, between the piezoelectric sheet 43 neighboring downward the piezoelectric sheet 42 and the piezoelectric sheet 44 neighboring downward the piezoelectric sheet 43 , an about 2 μm-thick common electrode 34 b is interposed formed like the common electrode 34 a . On the upper face of the piezoelectric sheet 41 , an about 1 μm-thick individual electrode 35 a is formed to correspond to each pressure chamber 10 (see FIG. 6 ). The individual electrode 35 a has a similar shape (length: 850 μm, width: 250 μm) to that of the pressure chamber 10 in a plan view, so that a projection image of the individual electrode 35 a projected along the thickness direction of the individual electrode 35 a is included in the corresponding pressure chamber 10 . Further, between the piezoelectric sheets 42 and 43 , an about 2 micron-thick individual electrode 35 b is interposed formed like the individual electrode 35 a . No electrode is provided between the piezoelectric sheet 44 neighboring downward the piezoelectric sheet 43 and the piezoelectric sheet 45 neighboring downward the piezoelectric sheet 44 , and on the lower face of the piezoelectric sheet 45 . Each of the electrodes 34 a , 34 b , 35 a , and 35 b is made of; e.g., a silver-palladium (Ag—Pd)-base metallic material.
The common electrodes 34 a and 34 b are grounded in a region (not shown). Thus, the common electrodes 34 a and 34 b are kept at the ground potential at a region corresponding to any pressure chamber 10 . The individual electrodes 35 a and 35 b in each pair corresponding to a pressure chamber 10 are in contact with leads (not shown) wired within the FPC 136 independently of another pair of individual electrodes so that the potential of each pair of individual electrodes can be controlled independently of that of another pair. The individual electrodes 35 a and 35 b are connected to the driver IC 132 through the leads. In this case, the individual electrodes 35 a and 35 b in each pair vertically arranged may be connected to the driver IC 132 through the same lead. In a modification, many pairs of common electrodes 34 a and 34 b each having a shape larger than that of a pressure chamber 10 so that the projection image of each common electrode projected along the thickness direction of the common electrode may include the pressure chamber, may be provided for each pressure chamber 10 . In another modification, many pairs of common electrodes 34 a and 34 b each having a shape somewhat smaller than that of a pressure chamber 10 so that the projection image of each common electrode projected along the thickness direction of the common electrode may be included in the pressure chamber, may be provided for each pressure chamber 10 . Thus, the common electrode 34 a or 34 b may not always be a single conductive sheet formed on the whole of the face of a piezoelectric sheet. In the above modifications, however, all the common electrodes must be electrically connected with one another so that the portion corresponding to any pressure chamber 10 may be at the same potential.
In the ink-jet head 1 , the piezoelectric sheets 41 to 45 are polarized in their thickness direction. That is, the actuator unit 21 has a so-called unimorph structure in which the upper (i.e., distant from the pressure chamber 10 ) three piezoelectric sheets 41 to 43 are layers wherein active layers are present, and the lower (i.e., near the pressure chamber 10 ) two piezoelectric sheets 44 and 45 are made into inactive layers. Therefore, when the individual electrodes 35 a and 35 b in a pair are set at a positive or negative predetermined potential, if the polarization is in the same direction as the electric field for example, the electric field-applied portion in the piezoelectric sheets 41 to 43 sandwiched by the common and individual electrodes works as an active layer (pressure generation portion) and contracts perpendicularly to the polarization by the transversal piezoelectric effect. On the other hand, because the piezoelectric sheets 44 and 45 are not influenced by an electric field, they do not contract in themselves. Thus, a difference in strain perpendicular to the polarization is produced between the upper piezoelectric sheets 41 to 43 and the lower piezoelectric sheets 44 and 45 . As a result, the whole of the piezoelectric sheets 41 to 45 is ready to deform into a convex shape toward the inactive side (unimorph deformation). At this time, as illustrated in FIG. 10 , the lowermost face of the piezoelectric sheets 41 to 45 is fixed to the upper face of the partition (the cavity plate) 22 partitioning pressure chambers, as a result, the piezoelectric sheets 41 to 45 deform into a convex shape toward the pressure chamber side. Therefore, the volume of the pressure chamber 10 is decreased to raise the pressure of ink. The ink is thereby ejected through the ink ejection port 8 . After this, when the individual electrodes 35 a and 35 b are returned to the same potential as that of the common electrodes 34 a and 34 b , the piezoelectric sheets 41 to 45 return to the original shape and the pressure chamber 10 also returns to its original volume. Thus, the pressure chamber 10 draws ink through the manifold channel 5 .
In another driving method, all the individual electrodes 35 a and 35 b are set in advance at a different potential from that of the common electrodes 34 a and 34 b . When an ejecting request is issued, the corresponding pair of individual electrodes 35 a and 35 b is once set at the same potential as that of the common electrodes 34 a and 34 b . After this, at a predetermined timing, the pair of individual electrodes 35 a and 35 b is again set at a potential different from that of the common electrodes 34 a and 34 b . In this case, at the timing when the pair of individual electrodes 35 a and 35 b is set at the same potential as that of the common electrodes 34 a and 34 b , the piezoelectric sheets 41 to 45 return to their original shapes. The corresponding pressure chamber 10 is thereby increased in volume from its initial state (the state that the potentials of both electrodes differ from each other), to draw ink from the manifold channel 5 into the pressure chamber 10 . After this, at the timing when the pair of individual electrodes 35 a and 35 b is again set at the different potential from that of the common electrodes 34 a and 34 b , the piezoelectric sheets 41 to 45 deform into a convex shape toward the pressure chamber 10 . The volume of the pressure chamber 10 is thereby decreased and the pressure of ink in the pressure chamber 10 increases to eject the ink.
On the other hand, in case where the polarization occurs in the reverse direction to the electric field applied to the piezoelectric sheets 41 to 43 , the active layers in the piezoelectric sheets 41 and 42 sandwiched by the individual electrodes 35 a and 35 b and the common electrodes 34 a and 34 b are ready to elongate perpendicularly to the polarization by the transversal piezoelectric effect. As a result, the piezoelectric sheets 41 to 45 deform into a concave shape toward the pressure chamber 10 . Therefore, the volume of the pressure chamber 10 is increased to draw ink from the manifold channel 5 . After this, when the individual electrodes 35 a and 35 b return to their original potential, the piezoelectric sheets 41 to 45 also return to their original flat shape. The pressure chamber 10 thereby returns to its original volume to eject the ink through the ink ejection port 8 .
Next, a manufacturing method of the ink-jet head 1 will be described.
To manufacture the ink-jet head 1 , the passage unit 4 and each of the actuator units 21 are separately manufactured and then both are bonded to each other. To manufacture the passage unit 4 , each plate 22 to 30 forming the passage unit 4 is subjected to etching using a patterned photoresist as a mask, to form openings illustrated in FIGS. 7 and 9 in the respective plates 22 to 30 . Next, the nine plates 22 to 30 are placed in layers with adhesives being interposed so as to form therein ink passages 32 . The nine plates 22 to 30 are thereby bonded to each other to form a passage unit 4 .
To manufacture each actuator unit 21 , a conductive paste to be individual electrodes 35 b is first printed in a pattern on a ceramic green sheet to be a piezoelectric sheet 43 . In parallel with this, conductive pastes to be common electrodes 34 a and 34 b are printed in a pattern on ceramic green sheets to be piezoelectric sheets 42 and 44 . After this, five green sheets to be piezoelectric sheets 41 to 45 are positioned in layers with a jig. The layered structure obtained is then baked at a predetermined temperature. After this, individual electrodes 35 a are formed on the piezoelectric sheet 41 of the baked layered structure. For example, the individual electrodes 35 a may be formed in the manner that a conductive film is plated on the whole of one surface of the piezoelectric sheet 41 and then unnecessary portions of the conductive film are removed by laser patterning. Alternatively, the individual electrodes 35 a may be formed by depositing a conductive film on the piezoelectric sheet 41 by PVD (Physical Vapor Deposition) using a mask having openings at portions corresponding to the respective individual electrodes 35 a . To this process, the manufacture of the actuator unit 21 is completed.
Next, the actuator unit 21 manufactured as described above is bonded to the passage unit 4 with an adhesive so that the piezoelectric sheet 45 may be in contact with the cavity plate 22 . At this time, both are bonded to each other based of positioning marks formed on the surface of the cavity plate 22 of the passage unit 4 and the surface of the piezoelectric sheet 41 , respectively.
After this, through-holes used for connecting vertically arranged corresponding individual electrodes 35 a and 35 b with each other are formed. The through-holes are then filled up with a conductive material. After this, an FPC 136 , used for supplying electric signals to the individual electrodes 35 a and 35 b and the common electrodes 34 a and 34 b , is bonded onto and electrically connected with bonding positions corresponding to the respective electrodes on the actuator unit 21 by soldering. Further, through a predetermined process, the manufacture of the ink-jet head 1 is completed.
As described above, unlike the other electrodes, individual electrodes 35 a to be the piezoelectric sheets 41 to 45 are not baked together with the ceramic materials. The reason for this is because the individual electrodes 35 a are exposed, they are apt to evaporate at a high temperature upon baking. As a result, it is difficult to control their thickness in comparison with the other electrodes 34 a , 34 b , and 35 b being covered with ceramic materials. However, even the thickness of the other electrodes 34 a , 34 b , and 35 b may somewhat decrease upon baking. Therefore, it is difficult to form them into a small thickness if keeping the continuity after baking is taken into consideration. Contrastively, because the individual electrodes 35 a are formed by the above-described technique after baking, they can be formed into a smaller thickness than the other electrodes 34 a , 34 b , and 35 b . Thus, in the ink-jet head 1 , by forming the individual electrodes 35 a in the uppermost layer to have smaller thickness than the thickness of the other electrodes 34 a , 34 b , and 35 b , the deformation of the piezoelectric sheets 41 to 43 including active layers is difficult to be restricted by the individual electrodes 35 a . Therefore, the electrical efficiency and the area efficiency of the actuator unit 21 are improved.
In the ink-jet head 1 , because the piezoelectric sheets 41 to 43 having active layers and the piezoelectric sheets 44 and 45 as the inactive layers are made of the same material, the material need not be changed in the manufacturing process. Thus, they can be manufactured through a relatively simple process, which may reduce the manufacturing cost. Furthermore, because each of the piezoelectric sheets 41 to 43 including active layers and the piezoelectric sheets 44 and 45 as the inactive layers has substantially the same thickness, a further reduction of cost can be achieved by simplifying the manufacturing process. This is because the thickness control can be more easily performed when the ceramic materials to be the piezoelectric sheets are applied to be put in layers.
Furthermore, in the ink-jet head 1 , separate actuator units 21 corresponding to the respective ink ejection regions are bonded onto the passage unit 4 , and are arranged along the longitudinal direction of the passage unit 4 . Therefore, each of the actuator units 21 , which may be uneven in dimensional accuracy and in positional accuracy of the individual electrodes 35 a , 35 b because they are formed by sintering or the like, can be positioned to the passage unit 4 independently from another actuator unit 21 . Thus, even in case of a long head, the increase in shift of each actuator unit 21 from the accurate position on the passage unit 4 is controlled, and both can accurately be positioned to each other. Therefore, even for individual electrodes 35 a , 35 b that are relatively apart from a mark, the individual electrodes 35 a and 35 b can not be shifted considerably from the predetermined position to the corresponding pressure chamber 10 . Thus results in good ink ejection performance and an improved manufacture yield of the ink-jet heads 1 .
In contrast to the above, if a long-shaped actuator unit 4 is made like the passage unit 4 , the more the individual electrodes 35 a and 35 b are apart from the mark, the larger the shift of the individual electrodes 35 a and 35 b is from the predetermined position on the corresponding pressure chamber 10 in a plan view when the actuator unit 21 is laid over the passage unit 4 . This causes, the ink ejection performance of a pressure chamber 10 to deteriorate, which also decreases the ink ejection performance of the ink-jet head 1 .
In addition, in the ink-jet head 1 constructed as described above, by sandwiching the piezoelectric sheets 41 to 43 by the common electrodes 34 a and 34 b and the individual electrodes 35 a and 35 b , the volume of each pressure chamber 10 can easily be changed by the piezoelectric effect. Further, because each of the piezoelectric sheets 41 to 43 having active layers is in a shape of a continuous flat layer, this can be easily manufactured.
Furthermore, the ink-jet head 1 has the actuator units 21 each having a unimorph structure in which the piezoelectric sheets 44 and 45 near each pressure chamber 10 are inactive and the piezoelectric sheet 41 to 43 distant from each pressure chamber 10 include active layers. Therefore, the change in volume of each pressure chamber 10 can be increased by the transversal piezoelectric effect. As a result, in contrast to an ink-jet head in which a layer including active layers is provided on the pressure chamber 10 side and a inactive layer is provided on the opposite side, the voltage to be applied to the individual electrodes 35 a and 35 b and/or high integration of the pressure chambers 10 can be lowered. By lowering the voltage to be applied, the size of the driver for driving the individual electrodes 35 a and 35 b can be reduced, thus reducing costs. In addition, each pressure chamber 10 can be reduced. Furthermore, even when the pressure chambers 10 are highly packed, a sufficient amount of ink can be ejected. Thus, leads to a decrease in the size of the head 1 and a highly dense arrangement of printing dots.
Further, in the ink-jet head 1 , each actuator unit 21 has a substantially trapezoidal shape. The actuator units 21 are arranged in two lines in a crisscross manner so that the parallel opposed sides of each actuator unit 21 extend along the longitudinal direction of the passage unit 4 , and the oblique sides of each neighboring actuator units 21 overlap each other in the lateral direction of the passage unit 4 . Because the oblique sides of each neighboring actuator units 21 overlap each other, when the ink-jet head 1 moves along the lateral direction of the ink-jet head 1 relatively to a print medium, the pressure chambers 10 along the lateral direction of the passage unit 4 can compensate each other. As a result, high-resolution printing, can be achieved by using a small-size ink-jet head 1 with a very narrow width.
Furthermore, because many pressure chambers 10 neighboring each other are arranged in a matrix in the passage unit 4 , the pressure chambers 10 can be disposed within a relatively small size at a high density.
In the above-described ink-jet head 1 , trapezoidal actuator units are arranged in two lines in a crisscross manner. However, each actuator unit may not be trapezoidal. Further, actuator units may be arranged in only one line along the longitudinal direction of the passage unit. Actuator units may be arranged in three or more lines in a crisscross manner.
FIG. 11 shows is a plan view of a head main body of an ink-jet head according to second exemplary embodiment of the invention. In the ink-jet head and ink-jet printer according to this second exemplary embodiment, because the parts other than the head main body are similar to those of the above-described first embodiment, the detailed description thereof will be omitted.
Referring to FIG. 11 , a head main body 201 of an ink-jet head according to this embodiment has a rectangular shape in a plan view extending in a main scanning direction. The head main body 201 includes a passage unit 204 in which a large number of pressure chambers 210 and a large number of ink ejection ports 208 are formed, as will be described later. Onto the upper face of the passage unit 204 , two actuator units 221 (In FIG. 11 , the right and left ones are denoted by reference numerals 221 a and 221 b , respectively) are bonded so as to neighbor each other. Each actuator unit 221 is disposed so that its one side B extends along the longitudinal direction of the head main body 201 . The neighboring actuator units 221 are disposed so as to be aligned with each other along the width (shorter length) direction of the head main body 201 with their oblique sides C being close to each other. An ink supply port 202 is open in the upper face of the passage unit 204 . The ink supply port 202 is connected with an ink supply source through a passage (not shown).
As shown in FIG. 12 , which representing the head main body 201 viewed from the printing face side, two ink ejection regions R 1 are provided in the lower face of the passage unit 204 to correspond to the respective regions where the actuator units 221 are disposed. A large number of small-diameter ink ejection ports 208 are arranged in the surface of each ink ejection region R 1 .
This exemplary embodiment shows a case of monochrome printing. Thus, the ink supply port 202 is supplied with a single color ink (e.g., black). To perform multicolor printing, head main bodies 201 corresponding in number to colors (for example, in case of four colors of yellow, cyan, magenta, and black, four head main bodies 201 ) are aligned along the lateral direction of the passage unit. The head main bodies 201 are supplied with color inks different from one another to print.
FIG. 13 is a sectional view illustrating the internal construction of the passage unit 204 . Referring to FIG. 13 , a manifold channel 205 is formed in the passage unit 204 . The manifold channel 205 communicates with an ink supply source through the ink supply port 202 , as a result, the manifold channel 205 is always filled up with ink. The ink supply port 202 is preferably provided with a filter for catching dust and dirt contained in ink.
The manifold channel 205 is formed in the most part of passage unit 204 to extend over the two ink ejection regions R 1 . In part of the manifold channel 205 corresponding to each ink ejection region R 1 , a large number of slender island portions 205 a are formed to be arranged at regular intervals. The length of each island portion 205 a is along the longitudinal direction of the passage unit 204 . In this construction, ink supplied through the ink supply port 202 passes between each neighboring island portions 205 a in the manifold channel 205 , and then it is distributed to pressure chambers 210 formed in the passage unit 204 in each ink ejection region R 1 .
Referring to FIG. 15 , each ink ejection port 208 is made into a tapered nozzle. The ink ejection port 208 communicates with a manifold channel 205 through a pressure chamber 210 having a substantially shape in a plan view and an aperture 212 . In this construction, ink is supplied from the manifold channel 205 to the pressure chamber 210 through the aperture 212 . By driving an actuator unit 221 , energy is applied to the ink in the pressure chamber 210 to eject the ink through the ink ejection port 208 .
FIG. 14 illustrates a detailed construction of the region denoted by reference Q in FIG. 13 . As shown in FIG. 14 , in a region of the upper face of the passage unit 204 corresponding to an ink ejection region R 1 , a large number of pressure chambers 210 are arranged in a matrix adjacent to or neighboring each other. Because the pressure chambers 210 are formed at a different level than that of the apertures 212 (as illustrated in FIG. 15 ), an arrangement such as that illustrated in FIG. 14 is possible in which each aperture 212 connected with a pressure chamber 210 overlaps another pressure chamber 210 . As a result, a dense arrangement of the pressure chambers 210 can be closely or densely arranged, which reduces the size of the head main body 201 and increases the resolution of the formed image.
FIG. 15 illustrates a specific construction of a passage from a manifold channel 205 to an ink ejection port 208 . Referring to FIG. 15 , the passage unit 204 is laminated with nine sheet materials in total, i.e., a cavity plate 222 , a base plate 223 , an aperture plate 224 , a supply plate 225 , manifold plates 226 , 227 , and 228 , a cover plate 229 , and a nozzle plate 230 . The above-described actuator units 221 are bonded to the upper face of the passage unit 204 to form a head main body 201 . The detailed construction of each actuator unit 221 will be described later.
An opening is formed in the cavity plate 222 to form a pressure chamber 210 as described above. A tapered ink ejection port 208 is formed in the nozzle plate 230 using a press. Communication holes 251 are formed through each of the plates 223 to 229 between the plates 222 and 230 . The pressure chamber 210 communicates with the ink ejection port 208 through the communication holes 251 . An aperture 212 is formed as an elongated hole in the aperture plate 224 . One end of the aperture 212 is connected with an end portion of the pressure chamber 210 (opposite to the end portion connecting with the ink ejection port 208 ) through a communication hole 252 formed in the base plate 223 . The aperture 212 is used to properly control the amount of ink to be supplied to the pressure chamber 210 and to prevent too much or too little ink from being ejected or released through the ink ejection port 208 . A communication hole 253 is formed in the supply plate 225 . The communication hole 253 connects the other end of the aperture 212 with the manifold channel 205 .
Each of the nine plates 222 to 230 forming the passage unit 204 is made of metal. The pressure chamber 210 , the aperture 212 , and the communication holes 251 , 252 , and 253 are formed by selectively etching each metallic plate using a mask pattern. The nine plates 222 to 230 are arranged in layers and bonded to each other so that the passage as illustrated in FIG. 15 is formed therein.
Referring to FIG. 16 , each actuator unit 221 includes five piezoelectric sheets 241 to 245 having the same thickness of about 15 microns (μm). The piezoelectric sheets 241 to 245 are made into continuous flat layers. One actuator unit 221 is disposed to extend over many pressure chambers 210 formed in one ink ejection region R 1 of the head main body 201 . This can lead to a highly dense arrangement of individual electrodes 235 a and 235 b in the actuator unit 221 . Each of the piezoelectric sheets 241 to 245 is made of a lead zirconate titanate (PZT)-base ceramic material having ferroelectricity.
Between the first and second piezoelectric sheets 241 and 242 from the top, an about 2 μm-thick common electrode 234 a is interposed formed on substantially the entire of the lower and upper faces of the piezoelectric sheets. Between the third and fourth piezoelectric sheets 243 and 244 , an approximately 2 μm-thick common electrode 234 b is also interposed. On the upper face of the first piezoelectric sheet 241 , an about 1 μm-thick individual electrode 235 a is formed to correspond to each pressure chamber 210 . As illustrated in FIG. 13 , the individual electrode 235 a has a similar shape to that of the pressure chamber 210 in a plan view, although the individual electrode 235 a is slightly smaller than the pressure chamber 210 . The individual electrode 235 a is disposed such that the center of the individual electrode 235 a coincides with the center of the corresponding pressure chamber 210 . Further, between the second and third piezoelectric sheets 242 and 243 , an about 2 μm-thick individual electrode 235 b is arranged and formed like the individual electrode 235 a . The portion where the individual electrodes 235 a and 235 b are disposed corresponds to a pressure generation portion A for applying pressure to ink in the pressure chamber 210 . No electrode is provided between the fourth and fifth piezoelectric sheets 244 and 245 , and on the lower face of the fifth piezoelectric sheet 245 . Each of the electrodes 234 a , 234 b , 235 a , and 235 b is made of, e.g., an Ag—Pd-base metallic material.
The common electrodes 234 a and 234 b are grounded in a region (not shown). Thus, the common electrodes 234 a and 234 b are kept at the ground potential at a region corresponding to any pressure chamber 210 . In order that the individual electrodes 235 a and 235 b in each pair corresponding to a pressure chamber 210 can be controlled in potential independently of another pair, they are connected with a suitable driver IC through a lead provided separately for each pair of individual electrodes 235 a and 235 b.
In the head main body 201 , the piezoelectric sheets 241 to 245 are to be polarized in their thickness. That is, the actuator unit 221 has a so-called unimorph structure in which the upper (i.e., distant from the pressure chamber 210 ) three piezoelectric sheets 241 to 243 are layers including active layers, and the lower (i.e., near the pressure chamber 210 ) two piezoelectric sheets 244 and 245 are made into inactive layers.
In this structure, when the individual electrodes 235 a and 235 b in a pair are set at a positive or negative predetermined potential, if the polarization is in the same direction as the electric field for example, the portion (an active layer, i.e., a pressure generation portion) in the piezoelectric sheets 241 to 243 sandwiched by the common and individual electrodes contracts perpendicularly to the polarization. On the other hand, because the inactive piezoelectric sheets 244 and 245 are affected by an electric field, they do not contract in themselves. Thus, a difference in strain is produced along the polarization between the upper piezoelectric sheets 241 to 243 and the lower piezoelectric sheets 444 and 245 . As a result, the piezoelectric sheets 241 to 245 are ready to deform into a convex shape toward the inactive side (unimorph deformation). At this time, because the lower face of the lowermost piezoelectric sheet 245 is fixed to the upper face of the partition dividing pressure chambers 210 , the pressure generation portion A of the piezoelectric sheets 241 to 245 deforms into a convex shape toward the pressure chamber 210 side to decrease the volume of the pressure chamber 210 . As a result, the pressure of ink is raised and ink is ejected through the ink ejection port 208 . After this, when a driving voltage is no longer applied to the individual electrodes 235 a and 235 b , the piezoelectric sheets 241 to 245 return to the original shape and the pressure chamber 210 also returns to its original volume. Thus, the pressure chamber 210 draws ink therein through the manifold channel 205 .
Next, the shape of the two actuator units 221 a and 221 b and the arrangement of individual electrodes 235 a and 235 b , i.e., the pressure generation portions A, will be described. FIG. 17 illustrates the shape of an actuator unit 221 a and the arrangement of pressure generation portions. FIG. 18 shows the relation between a seam portion between the actuator units 221 a and 221 b and pressure generation portions in an additional region.
The head main body 201 includes two actuator units 221 a and 221 b as described above. The two actuator units 221 a and 221 b have a similar shape and arrangement for pressure generation portions A.
As illustrated in FIGS. 11 and 17 , the actuator unit 221 a has a rectangular shape is disposed so that its side B extends in parallel with the longitudinal direction of the passage unit 204 and its other side C inclines to the longitudinal direction of the passage unit 204 . As illustrated in FIG. 17 , in the actuator unit 221 a , two regions P 1 and P 2 are provided which are separated in the lateral direction of the passage unit 204 by a straight line along the longitudinal direction of the passage unit 204 . That is, the regions P 1 and P 2 neighbor each other in the lateral direction of the passage unit 204 .
In region P 1 , a large number of pressure generation portions A 1 are arranged to neighbor each other in a matrix along the longitudinal direction of the passage unit 204 and along the other side C of the rectangle.
In region P 2 , pressure generation portions A 2 are arranged to neighbor each other in a matrix only in the vicinity of a corner D of the rectangle near to the actuator unit 221 b.
As shown in FIG. 18 , when the two actuator units 221 a and 221 b are arranged in line along the longitudinal direction of the passage unit 204 , the pressure generation portions A 2 of the additional region P 2 provided in the actuator unit 221 a are in a place corresponding to a region (shown as hatched region G in FIG. 18 ) where no pressure generation portion A can be disposed in the basic region P 1 because it is in the seam between the actuator units 221 a and 221 b . That is, the pressure generation portions A 2 of the additional region P 2 are disposed to correspond to a gap portion G between the pressure generation portions A 1 of the region P 1 provided in the actuator unit 221 a and the pressure generation portions A 1 of the region P 1 provided in the neighboring actuator unit 221 b . Thus, although no separate actuator unit is provided for ejecting ink through the gap portion G, the head main body 201 print through the longitudinal direction of the passage unit without any breaks.
In other words, because no pressure generation portion can be disposed in the region (region G) near the seam portion between the actuator units 221 a and 221 b , no pressure chamber 210 and no ink ejection port 208 also can be disposed in that region. Therefore, if the pressure generation portions A 2 were not disposed in the additional region P 2 provided in the actuator unit 221 a , printing in the portion corresponding to the gap portion G cannot be done. As a result, a portion where ink ejection cannot occur is produced in the seam portion between the actuator units 221 a and 221 b . However, because the pressure generation portions A 2 are disposed in the additional region P 2 provided in the actuator unit 221 a in a portion overlapping that region G in the lateral direction of the passage unit, there is no portion where ink ejection cannot occur. As a result, an image without any breaks can be formed on an image recording medium.
As described above, in this embodiment, the actuator unit 221 includes lines in each of which a large number of pressure generation portions A 1 and A 2 are arranged along the longitudinal direction of the passage unit 204 . Regarding the lengths of these lines along the longitudinal direction of the passage unit 204 , each line in the basic region P 1 is longer than each line in the additional region P 2 . Further, as for the number of lines along the lateral direction of the passage unit 204 , the number of lines in the additional region P 2 is the same as the number of lines that might exist in the length of the corresponding region G along the lateral direction of the passage unit 204 . Therefore, if an imaginary straight line is drawn to extend along the lateral direction of the passage unit 204 , the number of lines that the imaginary straight line crosses in the region where the neighboring actuator units 221 a and 221 b overlap each other is the same as the number of lines that the imaginary straight line crosses in the region where the neighboring actuator units 221 a and 221 b do not overlap each other.
The above-described feature can be achieved by arranging two actuator units 221 a and 221 b having the same construction. Thus, the arrangement of parts can be simplified and the cost and the number of process steps necessary for designing or manufacturing the actuator units 221 a and 221 b can be reduced.
Various exemplary arrangement of pressure generation portions A in the actuator unit 221 are described below. As shown in FIG. 19 , an exemplary arrangement of pressure generation portions in an actuator unit 255 is provided. FIG. 20 shows the relation between a seam portion between actuator units and pressure generation portions in an additional region in the arrangement of FIG. 19 .
The actuator unit 255 a of FIG. 19 is divided into three regions P 11 , P 12 , and P 13 in the lateral direction of the passage unit. The middle region P 11 in the lateral direction of the passage unit is used as a basic region and the remaining regions P 12 and P 13 are used as additional regions.
In the basic region P 11 , similar to the arrangement of FIG. 17 , a large number of pressure generation portions A 11 are arranged neighboring each other in a matrix along the longitudinal direction of the passage unit and along the other side C of the rectangle. In an additional region P 12 , pressure generation portions A 12 are arranged neighboring each other in a matrix in the vicinity of an acute corner D of the rectangle near to the actuator unit 255 b . In the other additional region P 13 , pressure generation portions A 13 are arranged neighboring each other in a matrix in the vicinity of an acute corner D of the rectangle far from the actuator unit 255 b.
Therefore, as illustrated in FIG. 20 , the pressure generation portions A 12 of the additional region P 12 of the actuator unit 255 a and the pressure generation portions A 13 of the additional region P 13 of the actuator unit 255 b are disposed in a gap portion G between the pressure generation portions A 11 of the basic region P 11 provided in the actuator unit 255 a and the pressure generation portions A 11 of the basic region P 11 provided in the neighboring actuator unit 255 b . Thus, the head main body 201 can be provided such that ink can be ejected with any breaks through the longitudinal direction of the passage unit.
Further, this embodiment can have the same advantages as those of the above-described first embodiment. More specifically, because the two actuator units 255 a and 255 b are arranged along the longitudinal direction of the passage unit 204 , even in case of a long passage unit 204 , high accuracy can be obtained in positioning of the actuator units 255 a and 255 b to the passage unit 204 . Therefore, good ink ejection performance can be obtained and the manufacture yield of ink-jet heads 201 can be remarkably improved. In addition, by sandwiching the piezoelectric sheets 241 to 243 between the common electrodes 234 a and 234 b and the individual electrodes 235 a and 235 b , the volume of each pressure chamber 210 can easily be changed by the piezoelectric effect. Further, the piezoelectric sheets 241 to 243 having active layers are continuous flat layers that can be easily be manufactured. Further, because an actuator unit 221 of a unimorph structure is provided in which the piezoelectric sheets 244 and 245 near to each pressure chamber 210 are inactive and the piezoelectric sheets 241 to 243 far from each pressure chamber 210 are layers including active layers, the change in volume of each pressure chamber 210 can be increased by the transversal piezoelectric effect. This leads to a lower voltage that needs to be applied to the individual electrodes 235 a and 235 b , as well as a high integration of the pressure chambers 210 . Further, in the passage unit 204 , because a large number of pressure chambers 210 neighboring each other are arranged in a matrix, the pressure chambers 210 can be disposed at a high density within a relatively small size.
In this embodiment, only two actuator units are arranged. However, three or more actuator units may be arranged. Arrangement of many actuator units can bring about a long ink-jet head. Such a long ink-jet head is advantageous because it can perform printing onto even a large-size image recording medium at a high speed.
FIGS. 21A and 21B illustrate head main bodies 271 and 272 according to modifications of the invention, in which four actuator units 261 a , 261 b , 261 c , and 261 d each constructed like an actuator unit 221 or 255 , are arranged in line on and bonded to passage units 274 having ink supply ports 273 near their both ends. Such an actuator units 261 a - d , like an actuator unit 221 or 255 , can be used in common to passage units different in length, e.g., from a relatively short passage unit as illustrated in FIG. 11 to a long passage unit as illustrated in FIG. 21A . Thus, such an actuator unit has high applicability as a component, which can reduce the manufacture cost.
In the head main bodies 201 and 271 as illustrated in FIGS. 11 and 21A , actuator units are arranged on a passage unit in a straight line with being aligned in the lateral direction of the passage unit. However, as in a head main body 272 illustrated in FIG. 21B for example, actuator units 261 a , 261 b , 261 c , and 261 d may be arranged in a crisscross form. However, from the viewpoint of making an ink-jet head compact, the arrangement as illustrated in FIG. 11 or 21 A is preferable in which actuator units are arranged in a straight line along the longitudinal direction of the passage unit with being regularly aligned in the lateral direction of the passage unit. Particularly in case of the arrangement of FIG. 11 or 21 A, the width of the ink-jet head can be made small. Therefore, when two or more ink-jet heads are arranged along their width to be supplied with inks of different colors for multicolor printing, they can be disposed within a compact space. This is further advantageous because occurrence of a shear in color of an image can be lessened even when an image recording medium runs in an oblique state upon printing.
Next, a third embodiment of the invention will be described. FIG. 22 is a plan view of a head main body of an ink-jet head according to this embodiment. In the ink-jet head and ink-jet printer according to this embodiment, because the parts other than the head main body is similar to that of the above-described first embodiment, the detailed description thereof is omitted here.
Referring to FIG. 22 , a head main body 301 of an ink-jet head according to this embodiment has a rectangular shape in a plan view extending in one direction. The head main body 301 includes a passage unit 304 in which a large number of pressure chambers 310 and a large number of ink ejection ports 308 are formed as will be described later. On the upper face of the passage unit 304 , four regular-hexagonal actuator units 321 (In FIG. 22 , they are denoted by reference numerals 321 a , 321 b , 321 c , and 321 d , respectively, in order from the right) are arranged in two lines in a crisscross manner and they are bonded to the upper face of the passage unit 304 . Each actuator unit 321 is disposed so that its opposed parallel sides (upper and lower sides) extend along the longitudinal direction of the head main body 301 . Each neighboring actuator units 321 are disposed so that their oblique sides is to be close to each other and have overlapping portions in the lateral direction of the passage unit.
Referring to FIG. 23 , four hexagonal ink ejection regions R 2 are provided in the lower face of the passage unit 304 to correspond to the respective regions where the actuator units 321 are disposed. A large number of small-diameter ink ejection ports 308 are arranged in the surface of each ink ejection region R 2 . A base block 302 is disposed on the upper face of the head main body 301 . A pair of ink reservoirs 303 each having a slender shape along the longitudinal direction of the head main body 301 is provided in the base block 302 . An opening 303 a is formed in the upper face of the base block 302 at one end of each ink reservoir 303 . Each opening 303 a is connected with a ink tank (not shown). As a result, each ink reservoir 303 is always filled up with ink.
FIG. 24 is a sectional view illustrating the internal construction of the passage unit 304 . Referring to FIG. 24 , manifold channels 305 acting as ink supply sources are formed in the passage unit 304 . Each manifold channel 305 communicates with an ink reservoir 303 through the corresponding opening 305 a formed in the upper face of the passage unit 304 . Each opening 305 a is preferably provided with a filter for catching dust and dirt contained in the ink.
Each manifold channel 305 branches at its opening 305 a to supply ink to a number of pressure chambers 310 as described later. When each hexagonal ink ejection region R 2 illustrated in FIG. 23 is evenly divided vertically into two regions, one manifold channel 305 is formed so as to correspond to one of the two regions. Eight manifold channel 305 is provided and each of them is so designed in shape as to distribute and supply ink to all pressure chambers 310 included in the corresponding region.
The ink ejection port 308 in one half region in the lateral direction of the passage unit communicates with one of the ink reservoirs 303 in a pair through a manifold channel 305 . The ink ejection port 308 in the other half region in the lateral direction of the ink-jet head communicates with the other ink reservoir 303 . By configuring the manifold channels 305 , the openings 305 a , and the ink reservoirs 303 in such a manner, two printing modes can be realized: (1) a mode in which the ink reservoirs 303 in the pair are supplied with ink of the same color to perform monochrome high-resolution printing; and (2) a mode in which the ink reservoirs 303 in the pair are supplied with ink of different colors to perform two-color printing with the single head main body 301 . This is a widely usable construction.
Referring to FIG. 26 , each ink ejection port 308 is made into a tapered nozzle. The ink ejection port 308 communicates with a manifold channel 305 through a pressure chamber 310 having a nearly rhombic shape in a plan view and an aperture 312 . In this construction, ink is supplied to the manifold channel 305 through the ink reservoir 303 and further supplied from the manifold channel 305 to the pressure chamber 310 through the aperture 312 . By driving an actuator unit 321 as will be described later, jet energy is applied to the ink in the pressure chamber 310 to eject the ink through the ink ejection port 308 .
FIG. 25 illustrates a detailed construction of the region denoted by reference E in FIG. 24 . As shown in FIG. 25 , in a region of the upper face of the passage unit 304 corresponding to an ink ejection region R 2 , a large number of pressure chambers 310 are arranged in a matrix neighboring each other. Because the pressure chambers 310 are formed at a different level from that of the apertures 312 as illustrated in FIG. 26 , an arrangement is possible in which each aperture 312 connected with a pressure chamber 310 overlaps another pressure chamber 310 . As a result, a highly dense arrangement of the pressure chambers 310 can be realized, which may reduce the size of the head main body 301 and increase the resolution of a formed image.
FIG. 26 illustrates a specific construction of a passage from a manifold channel 305 to an ink ejection port 308 . Referring to FIG. 26 , the passage unit 304 is laminated with nine sheet materials in total, i.e., a cavity plate 322 , a base plate 323 , an aperture plate 324 , a supply plate 325 , manifold plates 326 , 327 , and 328 , a cover plate 329 , and a nozzle plate 330 . The above-described actuator units 321 are bonded to the upper face of the passage unit 304 to constitute a head main body 301 . The detailed construction of each actuator unit 321 will be described later.
A rhombic opening is formed in the cavity plate 322 to form a pressure chamber 310 . A tapered ink ejection port 308 is formed in the nozzle plate 330 with a press. Communication holes 351 are formed through each of the plates 323 to 329 between the plates 322 and 330 . The pressure chamber 310 communicates with the ink ejection port 308 through the communication holes 351 . An aperture 312 as an elongated hole is formed in the aperture plate 324 . One end of the aperture 312 is connected with an end portion of the pressure chamber 310 (opposite to the end portion connecting with the ink ejection port 308 ) through a communication hole 352 formed in the base plate 323 . The aperture 312 is for properly controlling the amount of ink to be supplied to the pressure chamber 310 and preventing too much or too little ink from being ejected through the ink ejection port 308 . A communication hole 353 is formed in the supply plate 325 . The communication hole 353 connects the other end of the aperture 312 with the manifold channel 305 .
Each of the nine plates 322 to 330 forming the passage unit 304 is made of metal. The above-described pressure chamber 310 , aperture 312 , and communication holes 351 , 352 , and 353 are formed by selectively etching each metallic plate using a mask pattern. The nine plates 322 to 330 are put in layers and bonded to each other with being positioned to each other so that the passage as illustrated in FIG. 26 is formed therein.
Next, the structure of each actuator unit 321 will be described. Referring to FIG. 27 , the actuator unit 321 includes five piezoelectric sheets 341 to 345 having the same thickness of about 15 μm. These piezoelectric sheets 341 to 345 are made into continuous flat layers. One actuator unit 321 is disposed to extend over many pressure chambers 310 formed in one ink ejection region R 2 of the head main body 301 . This can realize a highly dense arrangement of individual electrodes 335 a and 335 b . Each of the piezoelectric sheets 341 to 345 is made of a lead zirconate titanate (PZT)-base ceramic material having ferroelectricity.
Between the first and second piezoelectric sheets 341 and 342 from the top, an about 2 μm-thick common electrode 334 a is interposed formed on substantially the whole of the lower and upper faces of the piezoelectric sheets. Also, between the third and fourth piezoelectric sheets 343 and 344 , an about 2 μm-thick common electrode 234 b is interposed. On the upper face of the first piezoelectric sheet 341 , an about 1 μm-thick individual electrode 335 a is formed to correspond to each pressure chamber 310 . As illustrated in FIG. 24 , the individual electrode 335 a has a similar shape to that of the pressure chamber 310 in a plan view though the individual electrode 335 a is somewhat smaller than the pressure chamber 310 . The individual electrode 335 a is disposed such that the center of the individual electrode 335 a coincides with the center of the corresponding pressure chamber 310 . Further, between the second and third piezoelectric sheets 342 and 343 , an about 2 μm-thick individual electrode 335 b is interposed formed like the individual electrode 335 a . No electrode is provided between the fourth and fifth piezoelectric sheets 344 and 345 , and on the lower face of the fifth piezoelectric sheet 345 . Each of the electrodes 334 a , 334 b , 335 a , and 335 b is made of, e.g., an Ag—Pd-base metallic material.
The common electrodes 334 a and 334 b are grounded in a region (not shown). Thus, the common electrodes 334 a and 334 b are kept at the ground potential at a region corresponding to any pressure chamber 310 . In order that the individual electrodes 335 a and 335 b in each pair corresponding to a pressure chamber 310 can be controlled in potential independently of another pair, they are connected with a suitable driver IC (not shown) through a lead provided separately for each pair of individual electrodes 335 a and 335 b.
In the head main body 301 , the piezoelectric sheets 341 to 345 are to be polarized in their thickness. That is, the actuator unit 321 has a so-called unimorph structure in which the upper (i.e., distant from the pressure chamber 310 ) three piezoelectric sheets 341 to 343 are layers including active layers, and the lower (i.e., near the pressure chamber 310 ) two piezoelectric sheets 344 and 345 are made into inactive layers.
In this structure, when the individual electrodes 335 a and 335 b in a pair are set at a positive or negative predetermined potential, if the polarization is in the same direction as the electric field for example, the portion (an active layer, i.e., a pressure generation portion) in the piezoelectric sheets 341 to 343 sandwiched by the common and individual electrodes contracts perpendicularly to the polarization. On the other hand, because the inactive piezoelectric sheets 344 and 345 are influenced by no electric field, they do not contract in themselves. Thus, a difference in strain perpendicular to the polarization is produced between the upper piezoelectric sheets 341 to 343 and the lower piezoelectric sheets 344 and 345 . As a result, the whole of the piezoelectric sheets 341 to 345 is ready to deform into a convex shape toward the inactive side (unimorph deformation). At this time, because the lower face of the lowermost piezoelectric sheet 345 is fixed to the upper face of the partition partitioning pressure chambers 310 , the piezoelectric sheets 341 to 345 deform into a convex shape toward the pressure chamber 310 side to decrease the volume of the pressure chamber 310 . As a result, the pressure of ink is raised and the ink is ejected through the ink ejection port 308 . After this, when application of the driving voltage to the individual electrodes 335 a and 335 b is stopped, the piezoelectric sheets 341 to 345 return to the original shape and the pressure chamber 310 also returns to its original volume. Thus, the pressure chamber 310 draws the ink therein through the manifold channel 305 .
To manufacture each actuator unit 321 , first, ceramic green sheets to be piezoelectric sheets 341 to 345 are put in layers and then baked. At this time, a metallic material to be individual electrodes 335 a or a common electrode 334 a or 334 b is printed into a pattern on each ceramic green sheet at need. After this, a metallic material to be individual electrodes 335 a is formed by plating on the whole of the upper face of the first piezoelectric sheet 341 and then unnecessary portions of the material are removed by laser patterning. Alternatively, a metallic material to be individual electrodes 335 a is deposited using a mask having openings at portions corresponding to the respective individual electrodes 335 a.
The actuator unit 321 thus manufactured is very brittle because it is made of ceramic. In particular, because corners of the actuator unit 321 are very easily broken, very delicate handling is required upon manufacture and assembling in order that any corner must not be brought into contact with another component.
However, as illustrated in FIG. 28A that is a plan view of the actuator unit 321 , in the ink-jet head according to this embodiment, the actuator unit 321 has a substantially regular-hexagonal profile. Any of six straight portions (sides) L 1 to L 6 included in this profile is connected with a neighboring straight portion L at about 120°. As a result, because any of the six corners (portions of each neighboring straight portions L crossing each other) θ1 to θ6 is not sharp, it is difficult to be broken off. Therefore, the actuator unit 321 as an expensive precise component may not easily brake in the middle of manufacture process. This may contribute to a reduction of manufacture cost.
The above effect is not obtained only when any of the corners θ1 to θ6 is formed into 120°. If a corner θn is formed into 90° or more, the corner θn is hard to be broken off. Therefore, for making any of the six corners θ1 to θ6 hard to be broken off, it suffices that any of the six straight portions L 1 to L 6 is connected with a neighboring straight portion L at the right angle or an obtuse angle (the minimum value of the angles θ1 to θ6 at the crossing portions is 90° or more). The hexagonal profile can freely be changed as far as the above condition is satisfied. FIG. 28B illustrates an actuator unit 355 as an example in which the above condition is satisfied.
Further, this embodiment also can bring about the same advantages as those of the above-described first embodiment. More specifically, because the four actuator units 321 are arranged along the longitudinal direction of the passage unit 304 , even in case of a long passage unit 304 , high accuracy can be obtained in positioning of the actuator units 321 to the passage unit 304 . Therefore, good ink ejection performance can be obtained and the manufacture yield of ink-jet heads 301 can be remarkably improved. Furthermore, by sandwiching the piezoelectric sheets 341 to 343 between the common electrodes 334 a and 334 b and the individual electrodes 335 a and 335 b , the volume of each pressure chamber 310 can easily be changed by the piezoelectric effect. Furthermore, the piezoelectric sheets 341 to 343 including active layers can easily be manufactured because they are continuous flat layers. Furthermore, because an actuator unit 321 of a unimorph structure is provided in which the piezoelectric sheets 344 and 345 near to each pressure chamber 310 are inactive and the piezoelectric sheets 341 to 343 far from each pressure chamber 310 are layers including active layers, the change in volume of each pressure chamber 310 can be increased by the transversal piezoelectric effect, and lowering the voltage to be applied to the individual electrodes 335 a and 335 b and/or high integration of the pressure chambers 310 can be intended. Further, in the passage unit 304 , because a large number of pressure chambers 310 neighboring each other are arranged in a matrix, the many pressure chambers 310 can be disposed at a high density within a relatively small size.
In the invention, the profile of each actuator unit is not limited to a hexagon. That is, the number of straight portion L may be not six but five, seven, eight, or more. Hereinafter, modifications in profile of each actuator unit will be described with reference to FIGS. 28 to 30 . In the below modifications, the same components as in the above-described third embodiment are denoted by the same reference numerals as in the third embodiment, respectively.
FIG. 29A is a plan view of a head main body in which each actuator unit is made into a heptagonal shape. FIG. 29B is a plan view of an actuator unit included in the head main body of FIG. 29A . As apparent from FIGS. 29A and 29B , in this modification, the components of the head main body 361 other than the actuator units 362 (In FIG. 29A , they are denoted by reference numerals 362 a , 362 b , 362 c , and 362 d , respectively, in order from the right) are constructed like those of the head main body 301 of the third embodiment.
Referring to FIG. 29B , each actuator unit 362 has its profile in which one corner of a hexagon according to the above-described embodiment has been cut off along a straight line. As a result, the number of straight portion L is seven (L 8 to L 14 ), and as for the angle of each corner, θ8 to θ12 are about 120° and θ13 and θ14 are about 150°.
FIG. 30A is a plan view of a head main body in which each actuator unit is made into an octagonal shape. FIG. 30B is a plan view of an actuator unit included in the head main body of FIG. 30A . As shown in FIGS. 30A and 30B , in this modification, the components of the head main body 371 other than the actuator units 372 (In FIG. 30A , they are denoted by reference numerals 372 a , 372 b , 372 c , and 372 d , respectively, in order from the right) are constructed like those of the head main body 301 of the third embodiment.
Referring to FIG. 30B , each actuator unit 372 has its profile in which two corners of a hexagon according to the above-described embodiment has been cut off along straight lines. As a result, the number of straight portion L is eight (L 15 to L 22 ), and as for the angle of each corner, θ15, θ16, θ19, and θ20 are about 120° and θ17, θ18, θ21, and θ22 are about 150°. In the above-described two modifications, because the angle of each corner of each cut-off portion is 150°, which is larger than that of the above-described hexagonal actuator unit 321 , the corner is harder to be broken off than that of the above-described hexagonal actuator unit 321 .
FIG. 31A is a plan view of a head main body in which two interconnecting portions of neighboring straight portions L in the actuator unit of the above-described third embodiment have been made into rounded portions F. FIG. 31B is a plan view of an actuator unit included in the head main body of FIG. 31A . As shown in FIGS. 31A and 31B , in this modification, the components of the head main body 381 other than the actuator units 382 (In FIG. 31A , they are denoted by reference numerals 382 a , 382 b , 382 c , and 382 d , respectively, in order from the right) are constructed like those of the head main body 301 of the second embodiment.
Referring to FIG. 31B , each actuator unit 382 has six straight portions L 23 to L 28 . Two interconnecting portions of neighboring straight portions L (L 23 and L 28 , and L 25 and L 26 ) in the actuator unit 382 are made into rounded portions F, where neighboring straight portions L are smoothly interconnected. Each rounded portion F is very hard to be broken off. Also in this case, the angle between each neighboring straight portions L, including two straight portions on both sides of each rounded portion F, (θ23 to θ27), is more than 90° (about 120°).
Next, the fourth exemplary embodiment of the invention will be described with reference to FIG. 32 . In the ink-jet head and ink-jet printer according to this embodiment, because the parts other than the head main body is similar to that of the above-described first embodiment, the detailed description thereof is omitted here.
A head main body 401 as illustrated in FIG. 32 includes a passage unit 404 in which a large number of pressure chambers and a large number of ink ejection ports are formed like the above-described embodiments. Onto the upper face of the passage unit 404 , two actuator units 421 (In FIG. 32 , the right and left ones are denoted by reference numerals 421 a and 421 b , respectively) are bonded neighboring each other. Each actuator unit 421 is disposed so that its one side B extends along the longitudinal direction of the head main body 401 . The neighboring actuator units 421 are disposed so as to be aligned with each other along the lateral direction of the head main body 401 with their oblique sides C being close to each other. Two actuator units 421 partially overlap each other along the lateral direction of the passage unit 404 . An ink supply port 402 is open in the upper face of the passage unit 404 . The ink supply port 402 is connected with an ink supply source through a passage (not shown).
An FPC 436 is bonded onto the upper face of each actuator unit 421 , and is used for supplying electric signals to individual and common electrodes in the actuator unit 421 . A driver IC 432 is bonded onto each FPC 436 , and is used as a driving circuit for generating driving signals to be supplied to the individual electrodes in the corresponding actuator unit 421 . Each FPC 436 is electrically connected with a control unit 440 including CPU, RAM, and ROM. The control unit 440 supplies printing data to each driver IC 432 . Each driver IC 432 generates driving signals for individual electrodes on the basis of the printing data.
Two regions P 21 and P 22 are provided in each actuator unit 421 . Of them, the basic region P 21 has a substantially rectangular shape having its sides in parallel with the respective sides of the corresponding actuator unit 421 . The basic region P 21 has its width somewhat shorter than the side B of the actuator unit 421 and its length of about ¾ the side C of the actuator unit 421 . In FIG. 32 , the basic region P 21 is provided in an upper portion of the actuator unit 421 . The additional region P 22 has a substantially rectangular shape having its sides in parallel with the respective sides of the corresponding actuator unit 421 . The additional region P 22 has the same width as the basic region P 21 and is disposed on the lower side of the basic region P 21 . The additional region P 22 is divided into two sub-regions P 22 a and P 22 b each having a substantially rectangular shape having its sides in parallel with the respective sides of the actuator unit 421 . The sub-region P 22 a has its width of about ⅕ the side B of the actuator unit 421 and its length of about ⅕ the side C of the actuator unit 421 . In FIG. 32 , the sub-region P 22 a is near the lower left acute portion of the actuator unit 421 . The sub-region P 22 b has its width of about ⅗ the side B of the actuator unit 421 and its length of about ⅕ the side C of the actuator unit 421 . In FIG. 32 , the sub-region P 22 b is on the lower side of the basic region P 21 and on the right side of the sub-region P 22 a.
In each of the basic region P 21 and the sub-regions P 22 a and P 22 b of the additional region P 22 , a large number of pressure generation portions are arranged with neighboring each other in a matrix along the longitudinal direction of the passage unit 404 and along the side C of the rectangle. Pressure chambers and ink passages including nozzles are formed in the passage unit 404 to correspond to the respective pressure generation portions.
When the two actuator units 421 a and 421 b each constructed as described above are arranged in line along the longitudinal direction of the passage unit 404 as illustrated in FIG. 32 , a region (hatched region G in FIG. 32 ) where no pressure generation portions exist is formed near the seam portion between the actuator units 421 a and 421 b . When the only pressure generation portions in the basic region P 11 are taken into consideration, the number of pressure generation portions along the lateral direction of the passage unit 404 in the vicinity of the seam portion is less than that in the portion other than the vicinity of the seam portion.
Hence, in this embodiment, utilizing the feature that the sub-region P 22 a of the additional region P 22 provided on the lower side of the basic region P 21 is provided to correspond to the region G where no pressure generation portions exist, near the seam portion, along the lateral direction of the passage unit 404 , the control unit 440 controls each driver IC 432 upon printing so as to drive pressure generation portions in the basic region P 21 and in the sub-region P 22 a of the additional region P 22 and not to drive any pressure generation portion in the sub-region P 22 b of the additional region P 22 . By this, because pressure generation portions in the actuator unit 421 are arranged in a region having substantially the same shape as in the actuator unit 221 of FIG. 18 , the number of pressure generation portions along the passage unit 404 near the seam portion is the same as that in the other portion. That is, because the pressure generation portions of the sub-region P 22 a of the additional region P 22 are disposed so as to correspond to the gap portion between the pressure generation portions of the basic region P 21 provided in one actuator unit 421 a and the pressure generation portions of the basic region P 21 provided in the neighboring actuator unit 421 b , the head main body 401 is capable of printing without any breaks throughout the longitudinal direction of the passage unit, and without providing any other actuator unit for ejecting ink through the gap portion. Further, because the pressure generation portion formation region in each actuator unit 421 has a similar shape to that of the actuator unit 421 , problems of distortion, bend, or the like, of the actuator unit 421 is difficult to arise.
As apparent from the above description, in this embodiment, ink passages may not be provided in the portion of the passage unit 404 corresponding to the sub-region P 22 b of the additional region P 22 .
The materials of each piezoelectric sheet and each electrode used in the above-described embodiments are not limited to the above-described ones. They can be changed to other known materials. The shapes in plan and sectional views of each pressure chamber, the arrangement of pressure chambers, the number of piezoelectric sheets including active layers, the number of inactive layers, etc., can be changed properly. Each piezoelectric sheet including active layers may differ in thickness from each inactive layer.
Furthermore, in the above-described embodiments, each actuator unit is constructed in which individual and common electrodes are provided on a piezoelectric sheet. However, such an actuator unit may not always be used bonded to the passage unit. Any other actuator unit can be used if it can change the volumes of the respective pressure chambers separately. Furthermore, in the above-described embodiments, pressure chambers are arranged in a matrix. However, the pressure chambers may be arranged in a line or lines. Further, although any inactive layer is made of a piezoelectric sheet in the above-described embodiment, the inactive layer may be made of an insulating sheet other than a piezoelectric sheet.
While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention as defined in the following claims. | A printhead module includes a plurality of rows of printhead nozzles, at least some of the rows including at least one displaced row portion, the displacement of the row portion including a component in a direction normal to that of a pagewidth to be printed, wherein the displaced row portions of at least some of the rows are different in length than the displaced row portions of at least some of the other rows. | 1 |
[0001] This application is a continuation-in-part of application Ser. No. 09/320,033, filed on May 26, 1999.
BACKGROUND OF THE INVENTION
[0002] 1. Field of The Invention
[0003] This invention relates to a vibrating screen mechanism and, more particularly, to a vibrating screen mechanism that is used to separate materials by size.
[0004] 2. Background of the Invention
[0005] For many years, vibrating screens have been used to separate products into different sizes. While some screens may be used in an environment that is relatively mild, other screens would be used in the harshest of environments, such as mines, quarries or plants, where materials, such a bauxite, gravel, crushed rock, limestone, cement, shale or clay, are sized into different sizes. In these harsh environments in which a vibrating screen operates, any mechanically moving parts can be fouled by dust, grit or grime from the materials being sized. The larger number of moving parts to operate the vibrating screen, the greater the probability there will be a mechanical failure. The simpler the operation of the vibrating screen, the less likely the mechanical parts will foul or break.
[0006] U.S. Pat. No. 4,444,656 to Nelson shows a vibrating screen with a plurality of transverse beams extending from side to side for vibrating the screen. A large number of beams are used, as well as a large number of moving parts. Likewise, a plurality of different motors are used, with each transverse beam having a different motor and a different rate of vibration.
[0007] Typical of the modern day vibrating screen are those screens disclosed in U.S. Pat. Nos. 3,378,142; 3,834,534; 4,180,458; 4,274,953; 4,340,469; 4,632,751; 5,100,539; 5,341,939; and 5,749,471. Unlike the present invention, in each of the referenced patents, a motor is attached to a frame to which is attached a screen. Activation of the motor causes the frame and consequently, the screen to vibrate. To allow such vibration, the frame is somehow affixed to isolating devices, usually springs. U.S. Pat. No. 3,378,142 imparts the vibrating force to the frame using “two drivingly coupled resiliently borne oscillating frames having alternative inter-engaging cross members.” U.S. Pat. No. 3,834,534 attaches a screen to a frame using springs and then allows the vibration mode of the screen and frame assembly to be controlled as well as slid beneath the screen. U.S. Pat. No. 4,180,458 uses a traditional structure, but isolates the structure to achieve better noise control. U.S. Pat. No. 4,274,953 mounts the vibration motor on the outside of the frame. U.S. Pat. No. 4,340,469 imparts the vibrational force to the frame and screen using unbalanced weights to generate gyrational vibratory motion. U.S. Pat. Nos. 4,632,751; 5,100,539; 5,341,939; and 5,749,471 each contain disclosures typical of vibrating frame/screens. Unlike the present invention, all of the inventions disclosed in the foregoing patents contain complex vibrating mechanisms with multiple mechanical parts and the vibrating force is imparted to a frame which in turn causes the screen to vibrate.
[0008] Not known to be the subject of a U.S. patent, is the vibrating screen apparatus utilized by J&H Equipment, Inc. (“J&H”), P.O. Box 928, Roswell, Ga. 30077, telephone number (800) 989-1606. Unlike the present invention which does not attach the vibrating screen apparatus to the screen and which does not require attachment through the screen, the J&H vibrating screen apparatus attaches rods across and through a screen. The rods are then attached to an overhead motor which, when activated, unlike the present invention, causes the entire apparatus, screen rods and screen to vibrate.
[0009] To simply and advance the prior art, a vibrating screen apparatus must, as does the present invention, reduce the number and complexity of the mechanical parts necessary to cause vibration of the screen and which in fact vibrate. Furthermore, for ease of maintenance, the entire vibrating apparatus should easily remove from the screen system.
SUMMARY OF THE INVENTION
[0010] It is an object of the present invention to provide a vibrating screen apparatus with a minimum amount of moving parts.
[0011] It is a further object of the present invention to provide a vibrating screen apparatus that is easily maintained and repaired.
[0012] It is yet another object of the present invention to provide a vibrating screen apparatus that is more reliable and economical to operate.
[0013] It is an even further object of the present invention to provide a vibrating screen apparatus that has less dust pollution or noise proliferation.
[0014] It is yet another object of the present invention to have vibrating bars that run lengthwise of the screen to impart the necessary vibrations to the screen.
[0015] It is yet another object of the present invention to suspend the vibrating bars and pull the screen taut by inflating air mounts below the vibrating bars.
[0016] It is yet another object of the present invention to provide tension rails for proper tensioning of the wire cloth that makes up the vibrating screen.
[0017] It is even another object of the present invention to mount the vibrating motor to the vibrating bars to cause the vibration of the wire cloth of the vibrating screen apparatus.
[0018] In the present invention, side plates are held into position by cross braces to form the frame of the present vibrating screen apparatus. The bottom of the frame is enclosed by a concave surface and a discharge outlet for the fine material that has gone through the last screen.
[0019] The screen is made of wire cloth that is tightened by tension rails on each side. The tension rails connect into hooks that are attached to the wire cloth and pulled tight between the respective sides of the frame.
[0020] Immediately below the screen are vibrating bars that run lengthwise of the screen. Attached to the underside of the vibrating bars is a vibrating motor that will cause the bars to vibrate. On top of the vibrating bars is some type of resilient material, such as rubber, to keep the vibrating bars from wearing out the screen.
[0021] The vibrating bars are mounted on air mounts set on cross braces between the sides of the frame. By inflating the air mounts, the screen is tightened to the predetermined tautness that is desired when the vibrating bar is lifted. Tension on the wire cloth increased and the vibrating mechanism is ready to be turned ON for operation.
[0022] Material to be sized comes in at the feed end of the vibrating screen apparatus. Material that is less than the predetermined size of the wire cloth will go through the screen and be less than the predetermined size. The remainder of the material that is larger than the predetermined size will come out of the discharge end of the vibrating screen apparatus.
[0023] If material is to be sized between a predetermined range, vibrating screen apparatuses can be stacked one on top of the other and material that comes out of the discharge end of other than the top vibrating screen apparatus would be of a predetermined size range depending upon the size of the individual screens therebetween.
[0024] To prevent air pollution by dust and other particles, a cover will cover the uppermost of the vibrating screen apparatuses. In the present invention, a rubber dust cover is used that is ratcheted down tightly into place to prevent noise proliferation or environmental pollution by dust.
[0025] Since the entire vibrating screen apparatus is gravity fed, the angle of the frame should be at least greater than the angle of repose of the material being sized. It is anticipated the angle of repose would typically be between 15°-45°.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] [0026]FIG. 1 is a perspective view of a demonstration model of the present invention with a portion cut away for illustration purposes.
[0027] [0027]FIG. 2 is a partial perspective cutaway view of the present invention illustrating the mounting of the vibrating bar.
[0028] [0028]FIG. 3 is a perspective view of the frame with the vibrating bar as mounted therein.
[0029] [0029]FIG. 3A is a cross-sectional view of the vibrating mechanism of FIG. 2 along section lines 3 A- 3 A, with the air mounts deflated.
[0030] [0030]FIG. 3B is a cross-sectional view of the vibrating mechanism of FIG. 2 along section lines 3 A- 3 A, with the air mounts inflated.
[0031] [0031]FIG. 4 is a side view illustrating the mounting of the motor to the vibrating bar.
[0032] [0032]FIG. 5 is an enlarged partial sectional view illustrating positioning of the air mounts between the vibrating bar and the cross braces.
[0033] [0033]FIG. 6 is an enlarged partial sectional view illustrating the tensioning of the wire cloth.
[0034] [0034]FIG. 7 is an enlarged partial sectional view illustrating contact between the vibrating bar and the wire cloth.
[0035] [0035]FIG. 8 is a partial sectional view illustrating the tensioning of the wire cloth and the securing of the shroud.
[0036] [0036]FIG. 9 is a side view illustrating the stacking of multiple vibrating screens to give multiple size materials therefrom.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0037] Referring to FIG. 1 of the present invention, a description of a demonstrator model of the vibrating screen apparatus 12 is shown. Material to be sized 14 feeds into the hopper 16 of the present invention. The hopper 16 may be pivoted on pivot point 18 so that the material to be sized 14 feeds out of the hopper 16 at the lower end 20 thereof into the vibrating screen body 22 . The vibrating screen body 22 has a frame 24 (shown in detail in FIG. 3) that is covered by a shroud 26 . The shroud 26 is held in position by ratcheted tie-downs 28 on the side walls 30 .
[0038] Inside of the vibrating screen body 22 is located a vibrating screen 32 that is typically made from a wire cloth. The vibrating screen 32 is tensioned between the respective side walls 30 by means of a tension rail 34 .
[0039] The angle of repose of the vibrating screen body 22 is great enough so the material be sized 14 will flow there along by gravity. The vibrating screen body 22 may be pivoted on pivot point 36 by means of hydraulic ram 38 . By extending the hydraulic ram 38 , the angle of repose can be increased. The slot 46 along with the pivot bar 48 allow for adjustment of the angle of repose between the hopper 16 and the vibrating screen body 22 . As the material to be sized 14 feeds through the vibrating screen body 22 , the larger particles 40 that will not go through the vibrating screen 32 and come out the discharge end 42 . The sized particles 44 that are smaller than the spaces in the vibrating screen 32 come out of the bottom of the vibrating screen body 22 .
[0040] Referring now to FIG. 2 of the drawings, an enlarged partial sectional view of the vibrating screen body 22 is shown. A portion of the shroud 26 has been cut away to illustrate the screen 32 being stretched between the sides 30 by means of tension rail 34 being tightened into position by bolts 50 . This will be explained in more detail in conjunction with FIG. 6.
[0041] Immediately below the vibrating screen 32 , which is made of wire cloth, is located two parallel vibrating rails 52 . The vibrating rails 52 run lengthwise along the vibrating screen body 22 from one end thereof to the other. The vibrating rails 52 are supported on the bottom thereof by air mounts 54 . The air mounts 54 are mounted to cross braces 56 by means of a mounting platform 58 .
[0042] Suspended below vibrating rails 52 is a vibrating motor 60 . Vibrating motor 60 attaches directly to vibrating rails 52 by any convenient means, such as base 62 . By turning on the vibrating motor 60 , through the base 62 , it causes the vibrating rails 52 to vibrate. The vibration of the vibrating rails 52 will in turn cause the screen 32 to vibrate. By inflating the air mounts 54 , the vibrating rails 52 will be the sole contact between the screen 32 , other than the edges that are tightened into place by tension rail 34 .
[0043] Turning now to FIG. 3 of the drawings, the frame 24 will be explained in more detail. The side walls 30 make up the sides of the frame 24 . Across the bottom of the frame 24 are lower cross braces 64 , which can be of any dimension; however, applicant has found that circular braces do not cause an accumulation of the material being sized.
[0044] Towards the upper part of the side walls 30 are the upper cross braces 66 . While the upper cross braces 66 can be of any particular size, square bar stock has found to be particularly suitable for this particular application. The upper cross braces 66 connect to the side walls 30 just below the vibrating screen mount 68 . The vibrating rails 52 are secured to the top of the air mounts 54 . The air mounts 54 are secured to the frame 24 by means of mounting platform 58 on upper cross braces 66 . The vibrating motor 60 suspends below the vibrating rails 52 by means of inverted base 62 .
[0045] Referring now to FIG. 3A and 3B in combination, the proper tensioning of the vibrating screen 32 is shown and explained. Referring first to the tightening of the vibrating screen 32 , enlarged FIG. 6 may be useful. The vibrating screen 32 is a wire cloth that is made with a predetermined mesh. The wire cloth has warp wires 70 that run lengthwise along the vibrating screen and shoot wires 72 that run perpendicular to the warp wire and perpendicular to the side walls 30 . For the purpose of tensioning vibrating screen 32 , some type of hook or connection is provided on the chute wires 72 . In the present case, hooks 74 are contained on the ends of the chute wires 72 .
[0046] To install the vibrating screen 32 , it is placed inside of the vibrating screen body 22 on the vibrating screen mount 68 . Then the hook side 76 of the tension rail 34 is placed inside of the hooks 74 . By tightening nuts 78 on bolts 50 , the slide side 80 of the tension rail 34 will slide along the side 30 and allow the tension rail 34 to tighten screen 32 by pulling against the hooks 74 . By tightening the nuts 78 on the bolts 50 , the vibrating screen 32 can be tightened to any desired tension. However, care should be exercised not to tighten too much, otherwise any bend contained in the warp wires or chute wires of the vibrating screen 32 may be deformed.
[0047] Again, referring to FIGS. 3A and 3B, the tightening of the shroud 26 will be explained in conjunction with enlarged cross-sectional view FIG. 8. The ratcheted tie-downs 28 will be explained in more detail. A strap 82 is connected to the shroud 26 by any convenient means, such as bolts 84 having eyelets with hooks 86 running therethrough. The hooks 86 connect to strap 82 , which are tightened by ratchet 88 . The other side of the ratchet 88 is connected to side wall 30 by means of flange 90 and bolt 92 .
[0048] In FIG. 3A, the air mounts 54 are deflated and the vibrating screen 32 is in its lowermost position. However, in FIG. 3B, the air mounts 54 are inflated so the vibrating rails 52 are raised up. In that manner, the vibrating screen 32 forms a crown and only comes into contact with the vibrating rails 52 . Therefore, when the vibrating rails 52 vibrate, the screen 32 will vibrate.
[0049] Referring to FIG. 7, the top part of the vibrating rail 52 is shown. The uppermost portion of vibrating rail 52 is capped by a rubber grommet 94 to prevent damage to the vibrating screen 32 . Any other type of resilient material to prevent damage to vibrating screen 32 can be used. In situations where a hot material is being sized, the rubber grommet 94 can be replaced with a heat resistant flexible material or even eliminated, if necessary.
[0050] Referring now to FIG. 5, the mounting of the vibrating rail 52 to the air mount 54 is illustrated. The vibrating rail 52 may be connected to air mount 54 by any convenient means, such as bolt 96 and nut 98 . On the underside, the air mount 54 is connected to the mounting platform 58 by means of similar bolt 96 and nut 98 . Also, the rubber grommet 94 is illustrated on the vibrating rail 52 .
[0051] [0051]FIG. 4 shows the mounting of the vibrating motor 60 on the underside of the vibrating rails 52 by means of bolts 100 and nuts 102 through base 62 . The vibrating motor may be of any particular type, but applicant has found that motors made by Visam are particularly suited for the present operation because of the adjustability of their speed and vibrating weight. Also, these motors have variable frequencies and may differ in power requirements according to the needs of the particular situation. The particular Visam motor can be selected and set according to the particular requirements of the job.
[0052] In actual operation, the vibrating screen apparatus can be tightened to a particular tension by inflating the air mounts 54 through inflating valve 104 as shown in FIG. 1. The inflating valve is connected by hoses (not shown) to the air mounts 54 . The pressure gauge 106 measures the amount of pressure that has been inserted in the air mount 54 . By use of the air mounts 54 and inflating them to a predetermined pressure, the tension on the vibrating screen 32 is continually adjusted. This adjustment eliminates the re-tensioning of the screen 32 or makes the re-tensioning a less frequent requirement.
[0053] By putting the material to be sized 14 into hopper 16 and allowing it to flow through the lower end 20 thereof into the vibrating screen body 22 , material to be sized 14 now flows along the vibrating screen body 22 . Particles that were too large to flow through the vibrating screen 32 will come out the discharge end 42 as larger particles 40 . The sized particles 44 will flow out of the bottom of the vibrating screen body 22 .
[0054] To size particles over a range, the vibrating screen bodies 22 may be stacked in a manner as shown in FIG. 9. The material to be sized 14 would then flow into the upper vibrating screen body 108 . The particles that were too large to flow through the upper vibrating screen 110 will then come out of discharge end 112 . However, the materials that flow through the upper vibrating screen 110 into the intermediate vibrating screen body 114 will then be vibrated along intermediate vibrating screen 116 . Hence, particles that would flow through upper vibrating screen 110 , but not intermediate vibrating screen 116 , would come out intermediate discharge 118 . Therefore, the particles coming out of intermediate discharge 118 are of a predetermined size range. For further refinement, a lower vibrating screen body 120 with a lower vibrating screen 122 is also included. From the lower discharge 124 , even finer size particles are discharged that would flow through upper vibrating screen 100 , intermediate vibrating screen 116 , but not lower vibrating screen 122 .
[0055] In the stacking of vibrating screen bodies as illustrated in FIG. 9, the coarser vibrating screens are at the top and the finer vibrating screens are at the bottom. From the lower vibrating screen body 120 is located a bottom chute 126 , with a bottom funnel 128 . Only the finest of particles would come out of bottom funnel 128 , which particles would flow through each of the upper vibrating screen 110 , intermediate vibrating screen 116 , and lower vibrating screen 122 . In this manner, a different range of sized particles can be determined in any given condition. | A vibrating screen apparatus for sizing materials is shown that has a minimum of moving parts therein. A vibrating motor is mounted below longitudinal vibrating bars. The vibrating bars are set on air mounts, which air mounts are between the vibrating bars and cross braces connected to the frame. The vibrating bars press against the underside of a vibrating screen to form a crown therein when the air mounts are inflated. The vibrating screen is stretched between the sides of the frame by tensioning rails. A shroud over the top of the frame is secured in place. Multiple size materials can be produced by stacking multiple vibrating screen apparatuses. | 1 |
CROSS-REFERENCES
[0001] This is a continuation-in-part application claiming priority to provisional patent applications Nos. 62/494,845 and 62/494,851 filed Aug. 22, 2016 (22 Aug. 2016), and non-provisional patent application Ser. No. 14/121,814 filed Oct. 20, 2014 (20 Oct. 2014).
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present disclosures relates to the field of medical payment processing systems, more particularly, this invention relates to coupling a set of machines remotely located from each other and communicating with each other continuously and simultaneously for providing a medical service provider's bill and payment controlled by data bearing records.
[0003] More particularly, the present invention relates to giving healthcare providers real time information regarding which healthcare service will be reimbursed and when, thus assisting healthcare providers with cash flow planning, cost benefit analyses and asset-allocation planning.
Background
[0004] American healthcare, both the public and private delivery systems, is deeply flawed, due to an information barrier which prevents healthcare providers from consistently determining what reimbursable healthcare can be provided to specific patients on a real time basis. This lack of reliable information on medical services service prevents heath care provides from making financially sound decisions as to the rendering of medical services. State and federal officials also need to find the most effective strategies to improve the financing and delivery of healthcare.
[0005] Reimbursement is provided by private and public payers. The private payers are primarily health and automobile insurance carriers (where medical benefits are included), and worker's compensation providers. The public payers are primarily governmental entities or programs such as Medicare and Medicaid.
[0006] A system is needed to allow healthcare providers real time information regarding which healthcare service will be reimbursed and when. This will provide healthcare providers with information suitable for cash flow planning, cost benefit analysis and asset allocation planning.
[0007] The present invention provides healthcare providers with real time regarding which healthcare service(s) will be reimbursed, and when, by identifying the individual patient, identifying said patient's healthcare service requirements, processing said patient's payer's forms for said patient's healthcare service requirements on a prospective basis; and communicating said patient's reimbursable patient's healthcare service options to the user of the present invention.
[0008] The present invention also integrates medical billing information systems. More particularly, the disclosed system integrates medical-bill compensation information, and prepares revenue cycle management supporting documentation for billing information systems in order to create supporting documentation for revenue-cycle management. This results in acceleration of the medical billing and collection processes.
[0009] One component of the present invention is a computer system a clearinghouse for automated processing of medical and healthcare-related invoices, supporting medical documents, and payment requests using accepted transmission protocols and record formats such as ANSI. A healthcare provider performs a medical service reimbursable by an insurer or other payer and transmits an invoice and supporting medical documentation to the system of the current invention, which is acknowledged, validated and, if complete, reformatted and transmitted to the responsible payer. The payer transmits a claim acknowledgment indicating acceptance or rejection of the invoice and supporting documents to the computer system, which converts the acknowledgment into human readable form and transmits it to the healthcare provider.
[0010] Specifically, the present invention is most effective for addressing the specific billing requirement of a defined group, such as the Atlantic Imaging Group (AIG). AIG is a national Preferred Provider Organization (PPO) that specializes in providing diagnostic testing services for patients administered by insurance companies, medical management companies, third party administrators and self-insured entities. These groups are considered the clients of AIG. AIG offers its services to its clients which include Personal Injury/Auto and Worker's Compensation under written agreements called “Payer Access Agreements.”
[0011] Payer Access Agreements require AIG to provide the testing, at negotiated prices, either directly or indirectly for the payer or obligor. AIG's agreements with its clients vary in price and responsibilities, which are all the primary obligation of AIG to its client. Under all circumstances, the client is required to pay AIG for medically necessary, covered services.
[0012] What about Benefits exhausted or Health Primary? The clients' only interaction with members of AIG's providers is that the client or payer uploads provider Federal Taxpayer Identification information from AIG into its system to identify the provider as a member of the AIG network. The client is not privy to AIG's Agreement with its provider.
[0013] AIG also negotiates agreements with testing facilities, and physicians/-medical practices that provide testing at their locations. This group is referred to as “providers” and the agreements are referred to as “Facility Agreements.” In all cases AIG uses a standard agreement that is, by design, onerous to the provider. In approximately nineteen years of operation, very few changes to the standard agreement have been negotiated by the provider. Generally, except as noted below, the terms, representations and warranties are consistent in the contracts. AIG selects which providers it chooses to have in its networks
[0014] In addition, in New Jersey and New York AIG operates under legislative provisions establishing the requirements for patients to use networks such as AIG. In New Jersey, AIG is a Voluntary Network established under guidelines established by the Department of Banking and Insurance. AIG is also an Organized Delivery System certified by the Department of Banking and Insurance and both entities are regulated by the department. In New York, AIG is an approved Diagnostic Testing Network and regulated by the New York Workers' Compensation Board and subject to the provisions of that Board, the Department of Health, and Department of Insurance. The regulations dictate compliance-requirements such as the form of ownership, services, geo-access and reporting.
[0015] The mainstream of AIG's business consists of a referral by AIG's client into AIG's call center of an approved test that is requested by a third party independent physician who is treating the patient. AIG's call-center personnel contact the patient, understand the patient needs and concerns such as claustrophobia, pregnancy or metal implants, and then determine a network provider that is capable of providing the testing services. The call-center personnel schedule the patient and follow up with the provider with a confirmation of the appointment. AIG's internal system, known as Managed Claims, tracks all appointments to assure that AIG receives the bills for scheduled appointments. This system controls all aspects of our business including scheduling, billing and claim management. Some of the specific modules that the system features are as follows:
[0016] The current invention allow entities such as AIG to engage in pre-funding. Using the present invention, AIG can contract with users of the present invention to accelerate the medical-bill payment cycle. In particular, the provider is paid a previously agreed upon rate once a ‘clean’ claim is received and entered into Managed Claims. AIG bills the carrier for reimbursement. If any portion of the claim is unpaid by the carrier, the Provider is subject to full recourse (Reconciliation). Prefunding happens when a user calls eligible claims to a queue within a chosen date range. When the user clicks “prefund selected,” the system generates a check for each claim that is to be prefunded (checked in the queue). The upper portion of the check stub includes pertinent claim information to help the provider identify which claim the check is payment for. This is referred to as a Prefunding Statement. Prefunding is first based on whether or not a Provider Contract includes Prefunding or Standard Funding, alternatively, in its product bundle. Provider Contracts and Contract options are stored in Managed Claims.
[0017] Secondarily, prefunding is based on a set of rules; AIG has specific rules that would make a service line and/or a claim prefund eligible or ineligible. These rules are part of the Prefunding Logic. An authorized user may override some of these rules by using the Force Prefunding tool which is done on a claim by claim basis as needed.
[0018] The actions of Prefunding, Force Prefunding and Deny Prefunding are all documented within the claim histories of the affected claims for user knowledge and audit history
[0019] Reconciliation is an automated way for AIG to recoup money from a provider that was not reimbursed by the payer. There are various reasons as to why this would happen which are outlined in the provider agreement. Rather than issuing the provider an invoice of money owed to AIG, these amounts are calculated and systematically offset against money owed to the provider.
[0020] There are three types of Reconciliation: Prefund Reconciliation; Billing Reconciliation; and Admin Fee Reconciliation.
[0021] Any time a check is issued from the system, Prefunded or Standard, the system completes a calculation for each Network Provider whereby it totals what is owed to the provider, and subtracts from that any outstanding balances that are owed back to AIG. Thus, the current invention offers accelerated medical invoice cycle completion because existing system execute at the claim level; the present invention allows reconciliation at the provider level.
[0022] Thus, for example, at the claim level′ means if $10.00 is owed back on Claim #1 from Provider A, and AIG owes Provider A $20.00 on Claim #2, when the check is issued for Claim #2, the check will be issued for $10.00 and will reference the remaining $10.00 as being offset against Claim #1 specifically. If there were two additional Claims #3 and #4, each worth $20.00 to the Provider, the Provider would get a total of 3 separate checks; one check for $10.00 referencing $10.00 reconciliation, and two checks for $20.00 each.
[0023] At the provider level′ means in the same scenario above, a single statement and check would be issued for $50.00 referencing the amounts paid on Claims #2, 3, and 4, and the amount deducted on Claim #1; the $10.00 offset would no longer specifically reduce the reimbursement on Claim #2, rather it would reduce the overall reimbursement of $60.00 to $50.00.
[0024] All Reconciliations are all documented within the claim histories of the affected claims for user knowledge and audit history.
[0025] In order to ‘trigger’ reconciliation of a balance, the claim related to the balance must be financially closed and an EOB (explanation of benefits) must be issued.
[0026] EOB notes trigger various actions within the system; some trigger a claim to appear in various queues to be worked by AIG staff (internal users) or queues that issue letters/bills to Patients relating to the collection of an outstanding balance. Some EOB notes just result in an informational EOB to be issued to the provider indicating a claim has been closed either because it has been paid in full or because the claim has been underpaid for one reason or another and the provider should expect a reconciliation against a future payment as a result of the underpayment. EOB notes and the associated actions are managed within AIG's systems by authorized users.
[0027] The actions of financially closing a claim and issuing an EOB set up the outstanding balance for reconciliation against the next payment to the provider. These actions are also documented within the claim histories of the affected claims; a copy of the original EOB is stored as well for user knowledge and audit history.
[0028] An EOB note is a comment tied to a service line that is applied when a payment or non-payment is posted to a claim. This note describes the payment or non-payment applied to the individual service line and is printed on the EOB (Explanation of Benefits) that is forwarded to the provider and stored within AIG's system.
[0029] Additionally, the present invention integrates medical claims processing for worker's compensation and auto accident claims processing. This clearinghouse computer system is an Internet clearinghouse system designed to process medical claims for personal injuries related to worker's compensation and auto accident matters.
[0030] Medical insurance pays the majority the medical treatment bills generated by medical providers, including doctors, health maintenance organizations (HMOs) and medical centers. S aid bills include details required by insurance companies prior to payment of said invoices. Due to the volume, complexity and possibility that said bills are not covered by insurance, the time between the generation of a particular bill and the payment of said particular bill generally takes months. This delay results in additional expenses to said medical providers due to the time value of money.
[0031] The deficiencies of the current process for payment of medical bills and the results are known. They include the following:
After hospitals render a service, bills and supporting documents for the service may or may not be submitted for payment; Hospital collections groups may not follow up effectively on deficiencies from said bills and supporting documents; and Said lack of follow up results in decreased working capital for hospitals as well as selling accounts receivables to collection agencies, further decreasing the value of the bills rendered.
[0035] The current art processes payments using a manual system. In a manual system that doesn't use automated management systems, claims are submitted for payment and are processed accordingly. Traditional means of communication such as phone calls, faxes and mail are used to “notify” submitters that the claim cannot be processed for various reasons. Some of these reasons are outlined below:
Insufficient data or improper data submitted Incomplete or incompatible dates submitted (for example, date of accident is after date of service) Lack of supporting documentation which is required for auto and workers' compensation claims Improper or missing ICD (International Classification of Diseases) or CPT
[0040] (Current Procedural Terminology is a medical code set that is used to report medical, surgical, and diagnostic procedures and services to entities such as physicians, health insurance companies and accreditation organizations) codes
[0041] While many of these issues are addressed by the use of an electronic claim submission system, the communication back to an individual with the ability to correct the issue is still often done through a manual, non-automated fashion such as a phone call, fax or form letter mailed. Even in cases where the communication is made electronically, proper timely payment relies upon an individual logging into a system and checking the claim status and addressing various issues.
How is the Process Currently Managed?
[0042] In a manual system that doesn't utilize an automated alert management systems, claims are submitted for payment and are processed accordingly. Traditional means of communication such as phone calls, faxes and mail are used to “notify” submitters that the claim cannot be processed for various reasons.
Shortcomings of Current Process
[0043] There is no formal process for communicating back to management or ownership the status of claims in process. Often the only way an owner and/or physician would know that claims are backed up and payments are delayed is if they would physically log into the system and verify that claims are being submitted and paid timely and not held up for various reasons. It is often unrealistic for an individual in this position to be able to pull such information.
[0044] Even in the event that this type of access is feasible, it is a “PULL” type request meaning that if the individual doesn't decide to go and get the information, it isn't made readily available. If an owner or physician forgets to check for 2-3 days due to a busy work schedule, status could go from being almost perfect to crisis mode in a very short period of time.
[0045] Hence, a need exists to overcome these shortcomings which is met by the current invention. More particularly, the current invention overcomes the shortcomings of the existing systems by ameliorating or eliminating delay.
[0046] Prior art includes several issued U.S. patents describing medical billing systems. These include U.S. Pat. No. 5,819,228 (Spiro) issued October 1998; U.S. Pat. No. 5,991,729 (Barry et al.) issued November 1999; U.S. Pat. No. 6,611,846 (Stoodley) issued August 2003; U.S. Pat. No. 6,886,016 (Hansen et al.) issued April 2005; U.S. Pat. No. 7,389,245 (Ashford et al.) issued June 2008; and U.S. Pat. No. 7,739,123 (Rappaport) issued June 2010. As well as US 20160012402 (Neal).
[0047] None of these patents teach elimination or minimization of delay. In fact, none disclose a mechanism of payment to the medical service providers issuing invoices or bills for their services to insurers or other liable entities.
[0048] Computerized systems also abound for factoring transactions between a funding source and bill-generator to advance funds to the billing entity prior to payment by the liable consumer or third-party such as an insurer. Such a system and method is taught in U.S. Pat. No. 7,617,146 (Keaton et al.) issued Nov. 10, 2009, for example. Such disclosures fail to teach the means to integrate said factoring with electronic clearinghouses, encrypted communications, insurance checklists, government requirements such as HIPAA, or integrated payment systems.
[0049] The present invention provides healthcare providers with real time regarding which healthcare service will be reimbursed and when by identifying the patient, identifying said patient's healthcare service requirements, processing said patient's payer's forms for said patient's healthcare service requirements on a prospective basis; and communicating said patient's reimbursable patient's healthcare
[0050] Data are “Pushed” as opposed to being “Pulled” to anyone within eyesight of a display device of the client's choosing. The only limitation is that the device must accept a video signal from a High Definition Multimedia Interface (HDMI) output.
[0051] Thus, the “Human” factor is removed since the system runs in the background in an unattended mode and the results are displayed in dashboard format on the screen for easy viewing. The dashboard is displayed continuously, 24×7×365.
Advantages of the Current Invention
[0052] The present invention substantially fulfills the foregoing unmet needs. The preferred embodiment of the present invention provides a web-based advanced payment claims processing system that does the following:
Provides a web-based tool that allows receipt of an electronic or hard copy claim and immediately begin processing the claim to ensure that it is a “clean claim.” This processing is done by appropriate personnel who utilize a check-list to ensure that the claim is in fact “clean.” This likely involves obtaining missing medical information and medical reports. Communicates all status and updates regarding the claim to the provider, medical management company and insurance carrier via the secure web interface. Ensures prompt payment to the provider, typically within 14 days of receipt of a “clean claim” via pre-funding. Invoices the carrier based on the approved, clean claim. Receives payment from the carrier and reconciles the claim (with the difference being an administrative fee for handling the claim).
[0058] As commonly understood, the following key terms are defined as:
Provider—a hospital or surgical center that has provided medical services (typically emergency medical services) to an individual who required medical attention due to a personal injury resulting from a Workers' Compensation injury or automobile accident. Carrier—typically an insurance company that is responsible for paying a claim for medical services rendered for personal injury related services provided at a hospital or surgical center. HIPAA—the U.S. Health Insurance Portability and Accountability Act of 1996. HIPAA ASC X 12—HIPAA ASC X12 version 5010 are new sets of standards that regulate the electronic transmission of specific healthcare transactions, including eligibility, claim status, referrals, claims, and remittances. Covered entities, such as health plans, healthcare clearinghouses, and healthcare providers, are required to conform to the new transaction set standards. Medical Management Company (MMC)—an MMC provides planning, management, cost containment and design services to physicians and other healthcare providers.
[0064] With respect to worker's compensation and auto-claims processing, the present invention substantially fulfills the foregoing unmet needs.
[0065] The Internet Worker's Compensation and Auto Accident Claims Process Clearinghouse Computer System component of the present invention is an Internet clearinghouse system designed to process medical claims for personal injuries related to worker's compensation and auto accident matters.
[0066] The system features the ability to take in many different formats such as ANSI, XML, CSV and even paper claims and process claims for virtually all carriers either electronically or via a print to mail function known as “Banker Box.” The system has the ability to process claims through a web-based, secure user interface or through what we call a “lights out” option whereby claims are processed and results transmitted via secure electronic feeds without any user intervention.
[0067] The present invention has both strategic and tactical advantage over existing products. In particular, the present invention is the only electronic direct link to the New York State Insurance Fund (NYSIF). All Worker's Compensation claims based out of New York State must get transmitted to NYSIF. We also transmit electronically to the New York Worker's Compensation Board (NY-WCB). Our electronic transmission is traceable and confirmed and it is required for the carrier to be able to submit an HP1 for late payment.
[0068] New York State has special requirements for the submission of ANSI claims for a series of questions that are required and specific to New York State. the computer system of the current invention works with our submitters to populate these questions into the proper sections of the ANSI files so claims are processed properly and paid promptly.
[0069] The present invention offers multiple avenues to get data into our system and we provide the necessary outputs to assure prompt payment of the claim. Typically payments are made within 10-14 days of submission of a “clean claim.” Insurance companies often report that the main reason for claim payment delays is due to claims being submitted with missing or invalid information. While the computer system of the current invention does not (and will not) change claim data, we do offer an interface and proper communication and reporting to advise all submitters of information needed in order to be able to process their claim cleanly and get them paid.
[0070] The present invention extraction module is an internal sub-section of the system that generates the various outputs necessary to facilitate claim payment and proper reporting. The majority of the work the extraction module does is to create ANSI x-12 output files that are sent to carriers for payment and submitters for status updates. The module also creates certain forms that may be printed manually for signature by the submitter such as the HP1, the Pennsylvania LIBC9 and others. There are also other entities (such as NYSIF and the New York State Worker's Compensation Board) that receive files in non-ANSI standards from us such as XML and CSV.
[0071] Unlike health claims, PIP claims require supporting documentation from the medical provider in order to be eligible for payment. This often a pain point for many submitters as the Practice Management systems often don't “talk to” the billing systems. The present invention addresses this issue for our submitters by offering multiple processes to make the submission easy. Supporting documentation can be “attached” and sent in with a pre-printed bar coded that links the documentation to the claim. The present invention also offer a unique process called “InstaDoc” whereby submitters can “drag and drop” through a graphical interface to attach supporting documents to claims. Finally, for the technically savvy submitters, the present invention offers specific segments of the ANSI x-12 837 form to specify the file name of the associated attachment in the claim transmission. The present invention document all of these options in a “Companion Guide” which can be made available to all submitters during the implementation phase.
[0072] Through the present invention's On-Line User Interface users can see “dashboard” views showing the status of their claims and ensure that the claim is “clean” before it is transmitted for payment. The present invention also sends emails and other reminders alerting users about claims that need their attention. The assurance of a “clean” claim for processing has been proven to significantly improve the number of days it takes to get paid.
[0073] The present invention offers submitters a “one stop shop” in that the present invention can accept claims for any carrier regardless of whether or not we (or one of our trading partners) have an electronic relationship with the carrier. In the case that there is no electronic relationship, the present invention has the ability to print to mail the claim and provide detailed tracking information about the claim through our user interface.
Typical Benefits
[0074] The typical benefits of the current invention includes a benefit to providers in that their claims paid within 14 days of acceptance which improves their cash flow tremendously. The percentage of the discount that they are giving up to receive the payment promptly makes business sense for the provider. The benefit to the processing service-provider is the spread on the prefunded amount and amount billed to the provider. The benefit to the MMC is a streamlined process for ensuring the claim is clean and approved at the proper rate.
Technical Features
[0075] The preferred embodiment of the present invention integrates certain technologies, unlike existing offerings, as follows:
The web site is HIPAA compliant and uses appropriate technologies for encryption, authentication and displaying medical information that has PII and PHI on the screens. The web site must either support or interface with an electronic clearing house that allows for the proper receipt and transmission of HIPAA ANSI X12 compliant electronic billing files. The 5010 version of the 837i and the UB04 form must be accepted electronically and in paper form and the proper receipt and acknowledgement files such as the 999 and 277/277 CA files must also be transmitted to the submitter as per HIPAA ANSI X12 guidelines. Invoices, payments and status updates must be transmitted appropriately and securely and may include third-party software and/or partners to accomplish such activities.
[0079] Inputs for the present invention include the following.
Provider bills are accepted electronically into iHCFA (ANSI HIPAA File Format 837i for Institutional Billing, v. 5010, UB04 for Hospital Billing). Keyed billing data is entered into web site via secure form. Hard copy of 5010 or UB04, may be keyed into web site and/or scanned. Payments are received from carriers to reconcile claims, difference between payment received and pre-fund disbursement is the fee for processing the claim within 14 days.
[0084] The process of the preferred embodiment of the present invention includes the following.
Prepare and track a required checklist of documentation associated with the provider bill until the claim is “clean” and complete. Submit the checklist, bill and supporting documents to the MMC and obtain acceptance. Upon acceptance, electronically submit the bill and attachments to the payer in their desired electronic format. Communicate with the provider when a bill is considered “complete” and under review (14 day or other time clock starts here). Provide a clock for users responsible for receiving the approval from the carrier. Calculate a previously agreed upon percentage of the approved bill amount. Integrate with financial systems to request funding and ultimately fund the provider within 14 days. Update the user interface (web site) with appropriate status and information. Receive the incoming payment from the carrier and reconcile the claim.
[0094] The outputs of the preferred embodiment of the present invention include the following.
Provide a complete checklist with dates and approvals to the MMC and/or facility indicating the status of the claim, 14 days period starts once the checklist is complete. Provide status updates to the facility, MMC and carrier via the user interface (web site). Payment within 14 days of approval to the provider. Provide a bill to the carrier for the services rendered. Provide various reports to web site users such as Claims in Processing, Tickler Reports and Prefunding Status Report.
SUMMARY OF THE INVENTION
[0100] A system for paying healthcare providers near-instantaneously for services rendered to a specific patient based exclusively on said patient's identity and medical needs. Additionally, the status of said bills, said processing and said payments may be displayed upon a display panel as a result of an automatic signal initiated by said system initiation.
[0101] The present invention allows for the near-instantaneous prospective payment to a medical provider for proposed services associated with a particular patient's medical needs. The present invention also allows near-instantaneous payment to a medical provider for services rendered to said patient for said medical need. The present invention may also be applied to public and private payers.
[0102] A system for inputting medical bills related to a specific patient for a specific medical need, processing said bills, and paying said bills nearly instantaneously. Said system is initiated by the identity of said patient and said patient's medical requirements. Additionally, the status of said bills, said processing and said payments may be displayed upon a display panel as a result of an automatic signal initiated by said system initiation.
[0103] The system is comprised of at least one computer capable of creating an intermediate data base containing information items related to said bills, insurance/carrier data requirements, and data related to said requirements.
[0104] The system is also capable of sending payments of said bills to providers as directed by said computer.
[0105] An important aspect of the invention is the system's capability to comply efficiently with the restrictions of the HIPAA and other criteria and specifications mandated by governmental authorities such as the federal Office of Management and Budget (OMB) and standards-setting organizations such as the American National Standards Institute (ANSI), E-Health Standards and Services (OESS), and the National Uniform Billing Committee (NUBC) of the American Hospital Association, in addition to proprietary and nonstandard data formats.
System Description
[0106] The system comprises of three major components which are as follows:
[0107] 1. Web Service—The web service simply “delivers” the dashboard information in a safe, secure, encrypted manner using the internet. The data is pushed out from our hosted website and database through a web service to the monitoring Receiving device.
[0108] 2. Receiving Device—The receiving device is a small device that utilizes a secure wireless connection to the internet and the device is programmed for the specific submitter. The software that resides on the device. The input to the device will be receiving the data sent from the Web Service. The processing on the device will be to format the data in a human readable dashboard format and output will be sending the dashboard to the display panel through the HDMI interface.
[0109] 3. Display Panel—The display panel is simply a display device that accepts an HDMI input and will display the dashboard information received from the receiving device.
[0110] The present invention will be providing to the submitter the Web Service configuration and the Receiving Device. The submitter will pay a monthly fee for the service and the rental of the device. Due to the many options on the display panel (Flat Screen TV, monitor, Reader Panel, etc.) and the environmental factors, the present invention does not provide the display panel or the cabling that runs from the receiving device to the display panel.
[0111] The system is written in Microsoft Visual Studio® 2010 using ASP.NET and C#.NET as the code base. The back-end database is Microsoft SQL Server® 2012.
BRIEF DESCRIPTION OF THE DRAWINGS
[0112] FIG. 1 illustrates a block diagram of an exemplary process flow in accordance with the principles of the invention (previously presented as FIG. 1 of 1 in Ser. No. 14/121,814).
[0113] FIG. 2 illustrates the relationship among the subsystems required for operation of the user-facing component, as it relates to the data-system component of the present invention.
[0114] FIG. 3 is a flowchart schematic of the key inputs and transformations of the worker's compensation element of the present invention (previously presented as FIG. 1 of 1 in Ser. No. 62/494,845).
[0115] FIG. 4 is a flowchart detailing the key elements and processes of the current invention (previously presented as FIG. 1 of 3 in Ser. No. 62/494,851).
[0116] FIG. 5 is a flowchart depicting the protocols necessary to enable the current invention (previously presented as FIG. 2 of 3 in Ser. No. 62/494,851).
[0117] FIG. 6 is a flowchart depicting the validation and error-summary processes (previously presented as FIG. 3 of 3 in Ser. No. 62/494,851).
[0118] 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 drawing.
DETAILED DESCRIPTION OF THE INVENTION
[0119] There are two major components of the current invention: the data system and the user-facing system.
[0120] Said user-facing system may be initiated by facial recognition or other bio-identity systems, or input key by a patient or other user in conjunction with input associated with said patient's healthcare requirements. Said requirements can be introduced to the present invention via an automated diagnostic system such as a video-feed or by keyed input.
[0121] The present invention is used in conjunction with a funds-holder such as a bank. The present invention will communicate an authorization to transfer funds from MedicaFund to said healthcare provider after said healthcare-provider/bill-generator confirms having rendered required services to said patient.
[0122] Said funds transfer amount is less than or equal to the reimbursement amount agreed to be paid by a payer (such as an insurer) to MedicaFund at some later date.
[0123] Said data system is composed of three separate computer systems which are remotely located from each other. Each of said computer systems accesses a data base which is uniquely associated with it.
[0124] Said data system is capable of sending and receiving data from said user facing data system; associating data related to said patients and said users which are proximate to said common medical service provider; and automatically sending said associated data concerning said patients to said users.
[0125] Said data system is composed of three computer systems. More particularly, a first computer system is associated with a healthcare service provider data base.
[0126] Said first computer data base has information related to patient and patient services rendered.
[0127] Said patient information such as any information that can be used to identify, contact, or locate an individual, either alone or combined with other easily accessible sources. It includes information that is linked or linkable to an individual, such as medical, educational, financial and employment information. Examples of data elements that can identify an individual include name, fingerprints or other biometric (including genetic) data, email address, telephone number or social security number. Said patient information is time stamped which allows said patient's proximity to said healthcare provider's facility to be determined.
[0128] Said patient services rendered information such as care, services, or supplies related to the health of an individual. It includes, but is not limited to, the following: (1) Preventive, diagnostic, therapeutic, rehabilitative, maintenance, or palliative care, and counseling, service, assessment, or procedure with respect to the psychical or mental condition, or functional status, of an individual or that affects the structure or function of the body; and (2) Sale or dispensing of a drug, device, equipment, or other item in accordance with a prescription.
[0129] Second computer system is associated with a healthcare payer data base.
[0130] Said second computer data base has information related to covered transactions and claims.
[0131] Said covered transactions are healthcare services which result in a contractual obligation to pay another for services rendered. Said covered transaction are payable if they meets regulatory and statutory requirements.
[0132] Said claims are healthcare claims or equivalent encounter information transaction is either of the following: (a) A request to obtain payment, and necessary accompanying information, from a healthcare provider to a health plan, for healthcare or (b) If there is no direct claim, because the reimbursement contract is based on a mechanism other than charges or reimbursement rates for specific services, the transaction is the transmission of encounter information for the purpose of reporting healthcare.
[0133] Third computer system is associated with a payment data base.
[0134] Said third computer data base has information related to eligibility and payments.
[0135] Said eligibility is information related to a person's qualification for the payment of said claim based on either of the following: (a) An inquiry from a healthcare provider to a health plan, or from one health plan to another health plan, to obtain any of the following information about a benefit plan for an enrollee: (1) Eligibility to receive healthcare under the health plan; (2) Coverage of healthcare under the health plan; (3) Benefits associated with the benefit plan or (b) A response from a health plan to a healthcare provider's (or another health plan's) inquiry described in paragraph (a) of this section.
[0136] Said payments are transmission of any of the following said healthcare provider's financial institution: (1) Payment; (2) Information about the transfer of funds; (3) Payment processing information including remittance advice.
[0137] Said three computer systems are in constant and simultaneous communication with each other.
[0138] More specifically, referring now to FIG. 1 regarding the data system, the following describes same.
[0139] One embodiment of the current invention operates under the name “MedicaFund”, which controls a website and database suitable for advance payment of provider-invoices for covered services, whereby a healthcare provider submits bills to the system for validation and pre-funding instead of to the insurer or other payer. When the current invention is used, the following transaction sequence typically occurs. A hospital performs a service. The hospital forwards bills and supporting documents to MedicaFund. MedicaFund utilizes an iHCFA clearinghouse to audit bills for completeness. iHCFA communicates any missing bill data back to assigned hospital personnel for completion. MedicaFund reviews supporting documents and checklist requirements. MedicaFund works with hospital personnel until all applicable checklist requirements have been satisfied. MedicaFund transmits bills, supporting documents, and checklist to MMC. MMC audits bills, supporting documents and checklist, then notifies MedicaFund if bill is “clean”.
[0140] MedicaFund notifies the hospital when the bill is “clean” and begins the 14-day payment clock. The MMC performs a bill review and eligibility assessment within 10 days or less. The MMC notifies MedicaFund when the bill is approved for payment. MedicaFund then pays the bill. Said transaction set can be completely automated when MMC is an MMC application and MedicaFund is also implement in software. Said MMC and MedicaFund applications can be run on a single computer or may be distributed among other processors. Payments and communications may be electronic or paper-based. Thus the computer-based system may integrate both paper and electronic communications, generating electronic mail in addition to traditional postal mail, as well as electronic payments and paper checks.
[0141] Paper-based implementations render the desirable short payment time frames and time value of funds unworkable. Therefore in the preferred embodiment, all communications and payments are electronic.
[0142] Referring now to the system overview of FIG. 1 , it is shown that the system interacts with three principal user groups: a medical provider bill-generator 100 , the payer 102 of the bills generated by provider 100 , and optional remote accessors 104 . Payer 102 is typically an insurance carrier, self-insured company, or other entity liable by contract or otherwise.
[0143] The system has two principal hardware components: an electronic clearinghouse system website and database 200 , and a MedicaFund website and database 202 . Electronic clearinghouse component 200 and MedicaFund component 202 may be configured into a single computer or installed in multiple, connected computers. Additionally, a multitude of remote hardware components may be incorporated into the system. These remote hardware components compose the Secure Message Center 204 .
[0144] For security purposes, clearinghouse 200 executes four software components, three inbound and two outbound data feeds. More particularly, clearinghouse component 200 processes the following data feeds.
[0145] There is an inbound ANSI feed 301 to clearinghouse 200 of a claim transaction in accordance with specification version 5010/837i mandated by HIPAA or transaction standards amended by OESS; inbound non-ANSI data feed 302 , in particular keyed data; inbound non-ANSI data feed 303 , in particular, a feed composed of a UB-04 claim in a form and format specified by OMB and the NUBC to be compliant with HIPAA.
[0146] The outbound components generated by clearinghouse component 200 are: an outbound ANSI feed 401 composed of files 9999 and 277CA which are HIPAA-approved communications concerning the status of incoming claim file claim feeds 301 , 302 and 303 . Outbound component 501 comprises database-to-database document transfer software containing claim data and status updates. Outbound component 501 is in communication with hardware component 202 .
[0147] MedicaFund hardware component 202 executes four types of software components. These are reporting software 502 ; processing software 503 ; communications software 504 between MedicaFund 202 and Secure Message Center 204 ; and communications software 505 between MedicaFund 202 and medical bill generator 100 and bill-payer 102 .
[0148] Report-generating software 502 includes four major software components. These are Incomplete Report software 600 , Tickler Report software 602 , Claims in Processing Report software 604 , and Aged Trial Balance Report software 606 .
[0149] Processing software 503 is internal processing software which compares claim information against a checklist, and reviews attached documents. Processing software 503 includes five software subcomponents: checklist inspection software 700 ; support document examination software 702 ; claim acceptance evaluator software 704 ; status updating software 706 ; and software to determine payable claim amount 708 .
[0150] Subcomponent 702 reviews a checklist of elements necessary to gain approval from payer 102 for the full payment of a claim. Subcomponent 702 also reviews form UB-04 for insurance-claim compliance. Subcomponent 702 connected with documents supporting said claim which are sent to and received from an MMC application. An MMC application provides planning, management, cost containment, design and other services to physicians and other healthcare providers. MMC applications are customized to the specific needs of medical services providers 100 and payers 102 .
[0151] Subcomponent 708 approves a payable dollar amount. Said amount is normally discounted for advance payment to provider 100 in anticipation of a predicted full payment from payer 102 .
[0152] Communications software 504 is internal processing software managing the interactions between MedicaFund 202 and the Secure Message Center 204 . Secure Message Center 204 includes a communication software subcomponent 900 to provider 100 notifying whether a claim was or was not accepted, and to give remote accessors 104 access to MedicaFund website and database.
[0153] Communications software 505 is internal processing software having three major software subcomponents. These subcomponents are payment software 800 which pays provider 100 by check or electronic transfer; bill-generating software 802 to payer 102 ; and electronic-payment transfer software 803 from payer 102 .
[0154] The interactions between the components include:
A. Inbound ANSI 5010/837i feed 301 to electronic clearinghouse 200 ; B. Inbound non-ANSI keyed data feed 302 to electronic clearinghouse 200 ; C. Inbound non-ANSI UB-04 claim 303 to electronic clearinghouse 200 ; D. Electronic clearinghouse 200 to outbound ANSI-compliant 9999 and 277CA file feed 401 ; E. Secure Message Center 204 to remote accessors 104 , and 104 to 204 (bidirectional); F. Communications software 504 to MedicaFund component 202 ; G. Communications software 504 to Secure Message Center 204 ; H. MedicaFund component 202 to report-generating software 502 ; I. Outbound component 501 to MedicaFund component 202 ; J. Secure Message Center 204 to provider/bill-generator 100 ; K. Communications subcomponent 900 to provider/bill-generator 100 ; and L. Communications subcomponent 900 to remote accessory 104 , and 104 to 900 (bidirectional).
The foregoing list sets forth major interactions but does not exclude other interactions nor does it suggest sequence or priority.
[0167] Additionally, data transmission is performed in a secured and encrypted manner, specifically employing Advanced Encryption Standard (AES) 256-bit protocol or other encryption method required by HIPAA or other controlling authority.
[0168] In the preferred embodiment, medical provider 100 generates ANSI 5010/837i data feed 301 which is throughput in an encrypted manner to electronic clearinghouse 200 . Subsequently, provider 100 generates non-ANSI keyed feed 302 and UB-04 claim feed 303 to electronic clearinghouse 200 .
[0169] Clearinghouse 200 generates encrypted outbound ANSI data feed 401 to provider 100 . Simultaneously clearinghouse 200 transmits claim data and status updates to Database-to-database transfer software 501 transmits claim data and status updates to MedicaFund component 202 using database-to-database software 501 . Upon receipt of the data from 501 , MedicaFund 202 initiates two software routines.
[0170] The first routine is report software 502 which includes the four subroutines Incomplete Report 600 , Tickler Report 602 , Claims in Processing Report 604 , and Aged Trial Balance Report 606 .
[0171] The second routine initiated is processing software 503 that is an iterative process involving checklist inspection 700 , support document examination 702 , claim acceptance evaluation 704 , status updating 706 and determination of a payable claim amount 708 .
[0172] The result of said iterative process will be both an update of reporting software 502 and activation of communication software component 505 . Communications software 505 uses elements of payment software 800 , bill-generating software 802 , and electronic-payment transfer software 803 to send either an electronic or paper payment to medical provider 100 , to bill payer 102 , and to receive a payment from payer 102 .
[0173] In an optional embodiment, MedicaFund 202 will also activate communications software 504 to enable participation by remote accessors 104 using Secure Message Center 204 running software subcomponent 900 for communications between provider 100 and remote accessors 104 .
[0174] The second major component of the current invention is the user-facing system. Said user-facing system is capable of receiving data from said data system; detecting patients and users which are proximate to a common medical service provider; and automatically sending data from said data system concerning said patients to said users.
[0175] Said user facing system is composed of three elements which are called as following:
[0176] 1. Web service—The web service simply “delivers” the dashboard information in a safe, secure, encrypted manner using the internet. The data is pushed out from a set of connected computers through a web service to the monitoring Receiving device.
[0177] 2. Receiving device—The receiving device is a small device that utilizes a secure wireless connection to the internet and the device is programmed for the specific submitter. The software that resides on the device. The input to the device will be receiving the data sent from the Web Service. The processing on the device will be to format the data in a human readable dashboard format and output will be sending the dashboard to the display panel through the HDMI interface.
[0178] 3. Display panel—The display panel is simply a display device that accepts an HDMI input and will display the dashboard information received from the receiving device.
[0179] The present invention will be providing to the submitter the Web Service configuration and the Receiving Device. Due to the many options on the display panel (Flat Screen TV, monitor, Reader Panel, etc.) and the environmental factors, the present invention is not limited a particular display panel or the cabling that runs from the receiving device to the display panel.
[0180] Said user facing system receives its data from said data system using a web Service. Said web service maintains a connection to said users and pulls from said data system.
[0181] Said receiving devices processes the data it receives from said web service and formats the data into a human readable dashboard view.
[0182] Said receiving device outputs the dashboard through a standard for connecting high-definition video device, such as a HDMI port of the device to said display panel of the user's choosing.
[0183] Said user facing system is written in an integrated development environment such as Microsoft Visual Studio using The head element contains, which use server control (rather than static control system such as hypertext markup language, which is the standard system for tagging text files to achieve font, color, graphic, and hyperlink effects on World Wide Web pages) such as ASP.NET and C#.NET as the code base. The back-end database is required such as Microsoft SQL Server.
[0184] Now referring to FIG. 2 for illustration, when a patient enters a healthcare provider facility 1000 , said patient's identifying information is entered into provider-computer 1100 . Said patient's healthcare service requirements are entered into provider-computer 1100 . Then computer 1100 sends said patient identity and requirements to said data system 2000 .
[0185] Said data system 2000 processes patient information as described above, including contact with said patient's payer to confirm coverage and amount of said coverage for said patient and patient's healthcare service requirements on a prospective basis. Said data system 2000 communicates said findings concerning said patient to web-service 3000 said patient's reimbursable care service options.
[0186] Web-service 3000 communicates with receiving device 4000 . Receiving device 4000 communicates to display panel 1500 said patient's reimbursable care service options. In an optional embodiment, receiving device 4000 may be proximal to provider-compute 1100 , or elsewhere in facility 1000 .
[0187] Referring now to FIG. 3 , a flowchart schematic is shown of the key inputs and transformations of the worker's compensation element of the present invention (as previously presented in FIG. 1 of 1 of prior provisional application Ser. No. 62/494,845). FIG. 3 demonstrates how said data system may be supplemented by optional components to address particular worker's compensation.
[0188] The workers' compensation component of the present invention teaches an apparatus for managing the pre-payment of medical and other healthcare bills using an intermediary, as follows.
[0189] The healthcare provider performs a medical or other covered service.
[0190] The provider creates an invoice in its own medical billing system or application
[0191] The provider either mails or transmits the invoice to its clearinghouse such as the computer system of the current invention.
[0192] If supporting documents for the invoice are not included, the provider adds them using the computer system disclosed; then
(a) The computer system application automatically validates the invoice for completeness; (b) Supporting documents are validated; and (c) If required, supporting documents are scanned and stored in Managed Claims.
[0196] Managed Claims authorizes and releases pre-funding of the invoice (i.e., pre-payment of the unpaid bill) to the healthcare provider.
[0197] The pre-funded invoice is transmitted or mailed to the insurer or other payer.
[0198] The payer pays the bill and transmits or sends an Explanation of Benefits (EOB) to the computer system of the current invention.
[0199] If the invoice was denied or only partial payment was made, reconciliation recourse is applied against the next bill submitted by the healthcare provider.
[0200] More particularly, FIG. 3 discloses an apparatus comprising: a computer system associated with a medical provider comprising at least one patient, at least one medical provider, at least one insurance provider and at least one Internet clearinghouse site, as follows:
(a) wherein, the patient receives medical services from the medical provider, (b) wherein, said medical services are memorialized in at least one bill, (c) wherein, the insurance provider is willing to pay said bill, (d) wherein, said willingness is dependent upon the receipt of the insurance provider of documentation of said bill, (e) wherein, the computer system is operative to transmit data provided by the medical provider bill said clearinghouse and personal information related to the patient, (d) wherein, the computer system is operative responsive at least in part to receiving said data, to obtain additional information corresponding to said bill and said patient information by transmitting data to said provider, to external users and said managed claims Internet site, (e) wherein, the computer system is operative responsive at least in part to receiving said data, to determine that the insurance provider may pay an amount equal to the amount set forth in said bill to the advance payer, and (f) wherein, the computer system is operative to cause a payment to the medical provider in an amount less than said payment to said payment to the advance payer in satisfaction for said bill.
[0209] In an alternate embodiment, the apparatus of FIG. 3 is a computer system comprising a wireless mobile device, as follows:
(a) wherein, the computer system is operative to receive said data through the wireless mobile device, and (b) wherein, the computer system is operative to cause a payment to the medical provider in an amount less than said payment to said payment to the advance payer in satisfaction for said bill through the wireless mobile device.
[0212] Still further, the apparatus disclosed in FIG. 3 may include data using AES 256-bit encryption.
[0213] Optional additional payment processing occurs as depicted in FIG. 4 , a flowchart detailing the key elements and processes of the current invention; FIG. 5 , the protocols necessary to enable the current invention; and FIG. 6 , a flowchart depicting the validation and error-summary processes ( FIGS. 4-6 were previously presented as FIGS. 1, 2 and 3, respectively, in provisional application Ser. No. 62/494,851).
[0214] Referring now to the processes depicted in FIGS. 4-6 , the present disclosure teaches an optional process to manage a clearinghouse for automated processing of medical and healthcare-related invoices, supporting medical documents, and payment requests, as follows.
[0215] A healthcare provider performs a medical service reimbursable by an insurer or other payer.
[0216] The provider creates invoices in its billing system using a standard format such as ANSI 5010 to create an 837P (professional) or 837I (institutional) record.
[0217] The provider transmits the invoices to the computer system of the present invention, preferably over the Internet using Secure File Transfer Protocol (SFTP).
[0218] The provider uses the computer system of the current invention to transmit supporting documents for the related invoice.
[0219] The computer system transmits an acknowledgment of the batch transmission, typically with an ANSI 999 response back to the provider.
[0220] The computer system validates that the invoice is complete and not missing required elements or fields.
[0221] The computer system validates that the bill has a supporting medical document.
[0222] The computer system notifies the provider that the invoice has been validation and or missing components.
[0223] The computer system transmits the bill and supporting documents to an insurer or other responsible payer.
[0224] The payer transmits a claim acknowledgment, preferably an ANSI 277 CA claim-acknowledgement response to the computer system, indicating its acceptance or rejection of the invoice and supporting documents.
[0225] The computer system converts the claim acknowledgment response into human readable terminology and transmits the converted claim acknowledgement back to the healthcare provider that provided the original invoice.
[0226] This optional process uses an apparatus as disclosed in FIGS. 4-6 , having a computer system associated with a medical provider system comprising at least one patient, at least one medical provider, at least one insurance provider and at least one user, as follows:
(a) wherein, the patient receives medical services from the medical provider, (b) wherein, said medical services are memorialized in at least one bill, (c) wherein, the insurance provider is willing to pay said bill, (d) wherein, said willingness is dependent upon the receipt of the insurance provider of documentation of said bill, (e) wherein, the computer system is operative to receive data provided by the medical provider system remotely located from said computer system, where said data correspond to said medical provider's services and includes personal information related to the patient, (f) wherein, the computer system is operative responsive at least in part to receiving said data, to obtain additional information corresponding to the patient from the said medical provider system, (g) wherein, the computer system is operative responsive at least in part to receiving and send data said user, and (h) wherein, the computer system is operative to cause a bill to said insurance provider in a form sufficiently satisfactory to yield a payment to said user.
[0235] In an alternate embodiment, the apparatus of FIGS. 4-6 is a computer system comprising a wireless mobile device, wherein the computer system is operative to receive said data through the wireless mobile device, and the computer system is operative to cause a payment to the medical provider in an amount less than said payment to said payment to the advance payer in satisfaction for said bill through the wireless mobile device.
[0236] In a still further option for security, the data may be encrypted using AES 256-bit encryption.
[0237] In the foregoing description, for purposes of explanation, specific numbers, materials and configurations are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that these teachings may be practiced without the specific details. In other instances, well known features are omitted or simplified in order not to obscure the present invention. Furthermore, for ease of understanding, certain method steps are delineated as separate steps, however, these separately delineated steps should not be construed as necessarily order dependent in their performance.
[0238] Persons skilled in the art will further recognize that the foregoing embodiments are illustrative and not limiting. This disclosure may be practiced with other embodiments and variations can be adapted to particular circumstances and material. Although certain embodiments and examples are necessarily chosen in describing and claiming the above disclosure, these should not inhibit broader or related applications without departing from the spirit of the invention. | A system for paying healthcare providers near-instantaneously for services rendered to a specific patient based exclusively on said patient's identity and medical needs. Additionally, the status of said bills, said processing and said payments may be displayed upon a display panel as a result of an automatic signal initiated by said system initiation. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of application Ser. No. 10/674,712, filed on Sep. 29, 2003, now U.S. Pat. No. 6,798,332, which is a divisional application of application Ser. No. 10/072,587, filed on Feb. 8, 2002, now U.S. Pat. No. 6,798,331, and claims the benefit of U.S. Provisional Application No. 60/267,306, filed on Feb. 8, 2001. The subject matters of the prior applications are incorporated in their entirety herein by reference thereto.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made with government support under Contract No. N00024-01-C-4034 awarded by the United States Navy.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a current control device for regulating current flow. The invention specifically described is a device wherein current flow is regulated by compression and expansion of a composite.
2. Related Arts
Mechanical circuit breakers are best described as a switch wherein a contact alters the electrical impedance between a source and a load. Mechanical breakers are typically composed of a snap-action bimetal-contact assembly, a mechanical latch/spring assembly, or an expansion wire. Such devices are neither gap-less nor shock resistant, therefore prone to chatter and subject to arcing. Chatter and arcing pose substantial problems in many high-voltage applications.
Variably conductive composites are applicable to current control devices. Compositions include positive temperature coefficient resistive (PTCR), polymer current limiter (PCL), and piezoresistive formulations. PTCR and PCL applications and compositions and piezoresistive compositions are described in the related arts.
Anthony, U.S. Pat. No. 6,157,528, describes and claims a polymer fuse composed of a PTCR composition exhibiting temperature-dependent resistivity wherein low resistivity results below and high resistivity results above a transition temperature.
PTCR composites are composed of a conductive filler within a polymer matrix and an optional nonconductive filler. Chandler et al., U.S. Pat. No. 5,378,407, describes and claims a PTCR composite having a crystalline polymer matrix, a nickel conductive filler, and a dehydrated metal-oxide nonconductive filler. Sadhir et al., U.S. Pat. No. 5,968,419, describes and claims a PTCR composite having an amorphous polymer matrix, a thermoplastic nonconductive filler, and a conductive filler. During a fault, the composite heats thereby increasing volumetrically until there is sufficient separation between particles composing the conductive filler to interrupt current flow. Thereafter, the composite cools and shrinks restoring conduction. This self-restoring feature limits PTCR compositions to temporary interrupt devices.
PCL composites, like PTCR compositions, are a mixture of a conductive filler and a polymer. However, PCL composites are conductive when compressed and interrupt current flow by polymer decomposition. For example, Duggal et al., U.S. Pat. No. 5,614,881, describes a composite having a pyrolytic-polymer matrix and an electrically conductive filler. During a fault, temperature within the composite increases causing limited decomposition and evolution of gaseous products. Current flow is interrupted when separation occurs between at least one electrode and conductive polymer. Gap dependent interrupt promotes arcing and arc related transients. Furthermore, static compression of the composites increases time-to-interrupt by damping gap formation. Neither PTCR nor PCL applications provide for the dynamically-tunable compression of a composite in response to electrical load conditions.
Piezoresistive composites, also referred to as pressure conduction composites, exhibit pressure-sensitive resistivity rather than temperature or decomposition dependence. Harden et al., U.S. Pat. No. 4,028,276, describes piezoresistive composites composed of an electrically conductive filler within a polymer matrix with an optional additive. Conductive particles comprising the filler are dispersed and separated within the matrix, as shown in FIGS. 1A and 1C . Consequently, piezoresistive composites are inherently resistive becoming less resistive and more conductive when compressed. Compression reduces the distance between conductive particles thereby forming a conductive pathway, as shown in FIGS. 1B and 1D . The composite returns to its resistive state after compressive forces are removed. However, piezoresistive compositions resist compression.
Pressure-based interrupt facilitates a more rapid regulation of current flow as compared to PTCR and PCL systems. Temperature dependent interrupt is slowed by the poor thermal conduction properties of the polymer matrix. Decomposition dependent interrupt is a two-step process requiring both gas evolution and physical separation between electrode and composite. Furthermore, decomposition limits the life cycle of a composition.
Active materials, including but not limited to piezoelectric, piezoceramic, electrostrictive, magnetostrictive, and shape-memory alloy materials, are ideally suited for the controlled compression of piezoresistive composites thereby achieving rapid and/or precise changes to resistivity. Active materials facilitate rapid movement by mechanically distorting or resonating when energized. High-bandwidth active materials are both sufficiently robust to exert a large mechanical force and sufficiently precise to controllably adjust force magnitude.
As a result, an object of the present invention is to provide a current control device tunably and rapidly compressing a pressure-dependent conductive composite. A further object of the present invention is to provide a device that eliminates arcing thereby facilitating a complete current interrupt. It is an additional object of the present invention to provide a device that quenches transient spikes associated with shut off.
SUMMARY OF THE INVENTION
The present invention is a current control device controlling current flow via the tunable compression of a polymer-based composite in response to electrical load conditions. The invention includes a pressure conduction composite compressed by at least one pressure plate. In several embodiments, the composite is compressed by a conductive pressure plate. In other embodiments, the composite is compressed by a nonconductive pressure plate and current flow occurs between two electrodes contacting the composite. The composite is variably-resistive and typically composed of a conductive filler, examples including metals, metal-nitrides, metal-carbides, metal-borides, metal-oxides, within a nonconductive matrix, examples including polymers and elastomers. Optional additives typically include oil, preferably silicone-based.
A compression mechanism applies, varies, and removes a compressive force acting on the composite. Compression mechanisms include electrically driven devices comprised of actuators composed of an active material extending and/or contracting when energized. Active materials include piezoelectric, piezoceramic, electrostrictive, magnetostrictive and shape memory alloys. Piezo-controlled pneumatic devices are also appropriate. Actuator movement adjusts the pressure state within the composite thereby altering resistivity within the confined composite.
Several advantages are offered by the present invention. Compression-based control of a pressure-sensitive conduction composite provides a nearly infinite life cycle. A gap-less interrupt eliminates arcing and arc quenching requirements. The present invention lowers fault current thereby avoiding stress related chatter. Parallel arrangements of the present invention offer power handling equal to the sum of the individual units.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram showing exemplary microstructures for composites before and after compression.
FIG. 2 is a flowchart of composite manufacturing method.
FIG. 3 is a side elevation view of a pressure switch with conductive pressure plates.
FIG. 4 is a side elevation view of a pressure switch with nonconductive pressure plates.
FIG. 5 is a side elevation view of a current controller comprised of four pressure switches wherein pressure plates are pushed by actuators.
FIG. 6 is a side elevation view of a current controller comprised of four pressure switches wherein pressure plates are pulled by actuators.
FIG. 7 shows a parallel arrangement of current controllers comprising a single unit.
FIG. 8 is a top elevation view of pressure switch showing cylindrical pores oriented through electrodes.
FIG. 9 is a section view of pressure switch showing cylindrical holes through switch thickness.
FIG. 10 is a section view of pressure switch showing cylindrical holes within composite.
FIG. 11 is a section view of pressure switch showing cylindrical holes filled with a temperature sensitive material.
FIG. 12 is a side elevation view of temperature activated switch.
FIG. 13 is a side elevation view of temperature activated switch.
REFERENCE NUMERALS
1 Current controller
2 Conductive filler
3 Nonconductive matrix
4 Composite
6 First electrode
7 Second electrode
11 Pressure switch
18 Pressure plate
19 Actuator
22 Force
30 Restoration element
31 Conductor
32 Insulator
33 Insulator
40 Hole
41 Temperature sensitive material
51 Temperature sensitive actuator
52 Wire
53 Wire
54 Nonconducting terminal
55 Rigid element
56 Thermal element
DESCRIPTION OF THE INVENTION
Two embodiments of the present invention are comprised of a rectangular solid composite 4 contacting and sandwiched between two or more plates, namely a planar first electrode 6 and a planar second electrode 7 , as shown in FIG. 3 , and a planar first electrode 6 and a planar second electrode 7 and two planar pressure plates 18 a , 18 b , as shown in FIG. 4. A pressure switch 11 is comprised of a composite 4 and electrodes 6 , 7 as shown in FIG. 3 or a composite 4 and pressure plates 18 a , 18 b as shown in FIG. 4 .
The composite 4 functionally completes the current path between first electrode 6 and second electrode 7 during acceptable operating conditions and interrupts current flow when a fault condition occurs. The composite 4 is either conductive or resistive based on the pressure state within the composite 4 . For example, the composite 4 may be conductive above and nonconductive below a threshold pressure. Alternately, the resistivity of the composite 4 may vary with pressure over a range of resistance values.
A typical composite 4 is a pressure dependent conductive material, for example a piezoresistive formulation, comprised of a nonconductive matrix 3 and a conductive filler 2 , as schematically shown in FIG. 1 . Preferred mixtures have a volume fraction below the percolation threshold wherein conductive filler 2 is randomly dispersed within the nonconductive matrix 3 . During compression, the nonconductive matrix 3 between conductive filler 2 particles is dimensional reduced thereby crossing the percolation threshold.
The nonconductive matrix 3 is a resistive, yet compressible material including but not limited to polymers and elastomers. Specific examples include polyethylene, polystyrene, polyvinyldifluoride, polyimide, epoxy, polytetrafluorethylene, silicon rubber, polyvinylchloride, and combinations thereof. Preferred embodiments are comprised of the elastomer RTV R3145 manufactured by the Dow Corning Company.
The conductive filler 2 is an electrically conductive material including but not limited to metals, metal-based oxides, nitrides, carbides, and borides, and carbon black. Preferred fillers resist deformation under compressive loads and have a melt temperature sufficiently above the thermal conditions generated during current interrupt. Specific metal examples include aluminum, gold, silver, nickel, copper, platinum, tungsten, tantalum, iron, molybdenum, hafnium, combinations and alloys thereof. Other example fillers include Sr(Fe,Mo)O3, (La,Ca)MnO3, Ba(Pb,Bi)O3, vanadium oxide, antimony doped tin oxide, iron oxide, titanium diboride, titanium carbide, titanium nitride, tungsten carbide, and zirconium diboride.
FIG. 2 describes a fabrication method for various composites 4 . Generally, composites 4 are prepared from high-purity feedstock, mixed, formed into a solid, and suffused with oil. One or more plates are adhered to the composite 4 .
Feedstocks include both powders and liquids. Conductive filler 2 feedstock is typically composed of a fine, uniform powder, one example being 325 mesh titanium carbide. Nonconductive matrix 3 feedstock may include either a fine, uniform powder or a liquid with sufficiently low-viscosity to achieve adequate dispersion of powder. Powder-based formulations are mechanically mixed and compression molded using conventional methods. Polytetrafluorethylene formulations may require sintering within an oven to achieve a structurally durable solid. Powder-liquid formulations, one example being titanium carbide and a silicone-based elastomer, are vulcanized and hardened within a die under low uniaxial loading at room temperature.
The solid composite 4 is placed within a liquid bath thereby allowing infiltration of the additive into the solid. Additives are typically inorganic oils, preferably silicone-based. The composite 4 is exposed to the additive bath to insure complete suffusion of the solid, whereby exposure time is determined by dimensions and composition of the composite 4 . For example, a 0.125-inch by 0.200-inch by 0.940-inch composite 4 composed of titanium carbide having a volume fraction of 66 percent and RTV R3145 having a volume fraction of 34 percent was suffused over a 48 hour period.
Conductive or nonconductive plates are adhered to the composite 4 either before or after suffusion. If prior to suffusion, plates are placed within the die along with the liquid state composite 4 . For example, a silicone elastomer composite 4 is adequately bonded to two 0.020-inch thick brass plates by curing at room temperature typically between 3 to 24 hours or at an elevated temperature between 60 to 120 degrees Celcius for 2 to 10 hours. If after suffusion, silicone adhesive is applied between plate and composite 4 and thereafter mechanically pressed to allow for proper bond formation.
A porous, nonconductive matrix 3 improves compression and cooling characteristics of the composite 4 without degrading electrical properties. A porous structure is formed by mechanical methods, one example including drilling, after fabrication of the solid composite 4 . Another method includes the introduction of pores during mixing of a powder-based conductive filler 2 with a liquid-based nonconductive matrix 3 . An additional method includes the introduction of pores during compression forming the composite 4 . Also, pores are formed by heating the composite 4 within an oven resulting in localized heating or phase transitions that result in void formation and growth. Furthermore, highly compressible microspheres composed of a low-density, high-temperature foam may be introduced during mixing. Pores are either randomly oriented or arranged in a repeating pattern. Pore shapes include but are not limited to spheres, cylinders, and various irregular shapes. A single pore may completely traverse the thickness of a composite 4 .
FIGS. 8-9 show an embodiment wherein a plurality of holes 40 traverse the cross section of a pressure switch 11 . FIG. 10 shows an embodiment wherein holes traverse the composite 4 within the pressure switch 11 .
FIG. 11 shows a further embodiment wherein holes 40 are filled with a temperature sensitive material 41 , examples including rods or springs composed of a shape memory alloy. Functionally, the temperature sensitive material 41 is typically a rubbery material below, see FIG. 11 a , and hard above, see FIG. 11 b , a phase transition temperature. More importantly, the temperature sensitive material 41 produces a large force above a transition temperature designed within the material as readily understood within the art. This force is sufficiently capable of moving the pressure plates 18 or electrodes 6 , 7 apart and interrupting current flow. The temperature sensitive material 41 is self restoring thereby facilitating current flow after the surrounding composite 4 has cooled.
FIGS. 12-13 show two embodiments wherein at least two temperature sensitive actuators 51 apply a compressive force 22 onto a composite 4 thereby allowing current flow. In FIG. 12 , current flows directly through the temperature sensitive actuators 51 a , 51 b , preferably a shaped memory alloy. When a fault occurs the temperature sensitive actuators 51 a , 51 b are heated and contract thereby decompressing the composite 4 and interrupting current. The composite 4 is compressed as the temperature sensitive actuator 51 cools. In FIG. 13 , current flows through the first electrode 6 and the second electrode 7 when temperature sensitive actuators 51 a , 51 b are heated by thermal elements 56 a , 56 b . Thermal elements 56 a , 56 b are deactivated when a fault condition occurs thereby decreasing the length of the temperature sensitive actuators 51 a , 51 b and reactivated after the fault condition is corrected thereby increasing the length of the temperature sensitive actuators 51 a , 51 b causing compression of the composite 4 and current flow.
FIGS. 5-6 show additional embodiments of the present invention comprised of four pressure switches 11 a , 11 b , 11 c , 11 d , a first electrode 6 , a second electrode 7 , two planar conductors 31 a , 31 b , four insulators 32 a , 32 b , 33 a , 33 b , a restoration element 30 , and a pair of actuators 19 a , 19 b.
Pressure switches 11 a , 11 b , 11 c , 11 d are composed of a pressure conduction composite 4 disposed between and adhered to two electrically conducting plates, as described above. A pair of pressure switches 11 are electrically aligned in a serial arrangement about a single electrode, either the first electrode 6 or the second electrode 7 . One electrically conducting plate from each pressure switch 11 directly contacts the electrode. Two such pressure switch 11 and electrode arrangements are thereafter aligned parallel and disposed between, perpendicular to and contacting a pair of conductors 31 a , 31 b so that each pressure switch 11 in a serial arrangement contacts a separate conductor 31 . Conductors 31 are composed of materials known within the art and should have sufficient strength to resist deformation when a mechanical load is applied. Thereafter, an insulator 32 is placed in contact with and attached or fixed to each conductor 31 . A typical insulator 32 is a planar element composed of an electrically nonconducting material with sufficient strength to resist deformation when a mechanical load is applied.
At least one restoration element 30 is disposed between and parallel to the serial arrangement of pressure switches 11 and electrodes 6 or 7 . The restoration element 30 is attached to separate electrically nonconductive insulators 33 a , 33 b . Thereafter, insulators 33 a , 33 b are mechanically attached to, perpendicularly disposed and between the conductors 31 a , 31 b . Insulators 33 a , 33 b electrically isolate the restoration element 30 from conductors 31 a , 31 b . The restoration element 30 decompresses the composite 4 within each pressure switch 11 , returning it to its original thickness, when the compressive mechanical load is removed from the insulators 32 a , 32 b . A restoration element 30 may be a mechanical spring or coil, a pneumatic device, or any similar device that provides both extension and contraction.
In preferred embodiments, an actuator 19 contacts an insulator 32 . In one embodiment, at least one actuator 19 is attached or fixed to each insulator 32 opposite of said conductor 31 , as shown in FIG. 5. A pair of actively opposed yet equal actuators 19 a , 19 b apply a mechanical load by pushing onto electrically nonconductive insulators 32 a , 32 b to compress the composite 4 within each pressure switch 11 a , 11 b , 11 c , 11 d , as shown in FIG. 5 b . In another embodiment, at least two actuators 19 a , 19 b are mechanically attached or fixed to a pair of insulators 32 a , 32 b , see FIG. 6 . Again, a pair of actively opposed yet equal actuators 19 a , 19 b apply a mechanical load by pulling on electrically nonconductive insulators 32 a , 32 b to compress the composite 4 within each pressure switch 11 a , 11 b , 11 c , 11 d , as shown in FIG. 6 b.
Variations to the described embodiments also include at least two or more actively opposed actuators 19 mechanically compressing one or more current controllers 1 . FIG. 7 describes a three-by-three arrangement of nine current controllers 1 , however not limited to this arrangement. In such embodiments, current controllers 1 are electrically connected parallel thereby providing a total power handling capability equal to the sum of the power handling of individual units.
One or more actuators 19 may be employed to drive two or more current controllers 1 . For example, a single actuator 19 or two actively opposed yet equal actuators 19 may apply a mechanically compressive load onto the current controllers 1 so that all are simultaneously compressed and decompressed. Alternatively, one or a pair of actuators 19 may apply a mechanically compressive load onto each individual current controller 1 . In this embodiment, it is possible to simultaneously drive all current controllers 1 or to selectively drive a number of units.
The embodiments described above may also include a current measuring device electrically coupled before or after the current controller 1 . This device provides real-time sampling of current conditions which are thereafter communicated to the actuators 19 . Such monitoring devices are known within the art.
An actuator 19 is a rigid beam-like element composed of an active material capable of dimensional variations when electrically activated. For example, the actuator 19 may extend, contract, or extend and contract, as schematically represented by arrows in FIGS. 5-6 . Extension of the actuator 19 increases the overall length of the actuator 19 . Actuators 19 are composed of electrically activated devices including piezoelectric, piezoceramic, electrostrictive, magnetostrictive, and shape memory alloy materials. For example, piezoelectric and piezoceramic materials may be arranged in a planar stack along the actuator 19 . Shape memory alloys are mechanically distorted by heating via electrical conduction or heat conduction from an adjacent body, one example including the composite 4 during fault condition. Alternatively, an actuator 19 may be a commercially available high-speed piezo-controlled pneumatic element comprised of a pneumatic diaphragm with pilot operated high-bypass value.
The description above indicates that a great degree of flexibility is offered in terms of the present invention. Although embodiments have been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. | A current control device is described wherein a pressure conduction composite is compressed and decompressed to alter its conductivity and thereby current conduction through the device. The pressure conduction composite is composed of a nonconductive matrix, a conductive filler, and an additive. The invention consists of electrodes and pressure plates contacting the composite. Electrically activated actuators apply a force onto pressures plates. Actuators are composed of a piezoelectric, piezoceramic, electrostrictive, magnetostrictive, and shape memory alloy materials, capable of extending and/or contracting thereby altering pressure and consequently resistivity within the composite. Two or more current control devices are electrically coupled parallel to increase power handling. | 8 |
This application is a continuation, of application Ser. No. 08/129,118, filed Nov. 2, 1993, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to a method and arrangement for determining machine-specific electromagnetic and mechanical status variables for electrodynamic rotary field machines supplied via inverters, such as, for example, asynchronous machines, synchronous machines and reluctance machines.
2. Discussion of Background and Relevant Information
Due to progress made in the field of power and information processing electronics, inverter supplied asynchronous, synchronous and reluctance machines are gaining increasing significance in drive technology.
Asynchronous machines are distinguished from synchronous machines and direct current machines by their greater sturdiness and lower production costs. When performing closed-loop control algorithms for dynamically high-quality field-oriented control concepts, the necessity arises, at low rpm of the asynchronous machines, of having a mechanical transducer detect the rotor position or rotor speed. Asynchronous machines can be dynamically operated without the use of position transducers and tachometers if the rpm exceeds a certain minimum predetermined value, in which case, the magnetic flux can be calculated from electrical variables from an induced voltage. However, this has not yet been successfully achieved when the asynchronous machine is operating in the low rpm range. Thus, ongoing research is attempting to replace mechanical transducers with mathematical models and/or to utilize physical phenomena.
An article at pages 349-351 of "etzARCHIV", No. 11, Vol. 12 (1990), entitled "Determination of the Stator Flux Space Vector of Saturated AC Machines" addresses these problems. The article describes a method in which an alternating current machine that is supplied via a pulse-width modulated alternating converter stage, carries out a real-time determination of the stator voltage vector once each oscillation period. According to this method, measurement errors in the values of the phase currents and phase voltages needed for the calculations can be kept small. Thus, there is no need for obtaining rotor speed measurements.
One disadvantage of this method is that inductances are calculated. Thus, voltage measurements need to be constantly obtained.
In a dissertation entitled "Entwurf und Aufbau Eines Nichtlinearen Zustands--Und Parameterbeobachters Fur Transient Betriebene Asynchronmaschinen" Design and Construction of a Nonlinear Status and Parameter Observer for Transient Operation Asynchronous Machines!, by Manfred Schrodl (Technische Universitat Wien Technical University of Vienna!, 1987, page 14f.), the author discusses how to determine a rotor flux from a stator equation in a rotary current machine. According to the dissertation, a "voltage model" is used as an aid, which is based on a formula: ##EQU1## in which the symbols have the following meanings: ψ R . . . rotor flux space vector
χ R . . . specific reactants
χ N . . . specific primary field reactance
μ S . . . stator voltage space vector
i S . . . stator current space vector
π S . . . specific stator resistance
δ' . . . stray coefficient
χ S . . . specific stator reactance
• . . . derivation over time.
According to this model, the flux can be determined solely by measuring electrical variables, eliminating the need for an electrical transducer. Additionally, when voltage space vector amounts are high--which is equivalent to a high rpm--the current-dependent terms, especially at a low load, only weakly influence the flux value. Accordingly, a good accuracy can be expected in these operating ranges.
A disadvantage of such a measuring method is that the influence of measurement errors and temperature-dependent stator resistance, and in the case of an analog construction, the drift of the integrators, increasingly worsen the quality of the model because of the lack of any feedback.
Synchronous machines have become popular because of improvements in the field of magnetic materials. Compared with asynchronous machines, synchronous machines have a simpler structure in terms of closed-loop control technology, and, because of very low rotor losses, operate with a higher efficiency as compared to asynchronous machines.
In order to carry out the control algorithms in dynamically high-quality field-oriented closed-loop concepts (or magnet-wheel-oriented closed-loop control concepts), a mechanical transducer must be employed that detects the magnet wheel position. Efforts have been made to replace the mechanical transducer with mathematical models or to utilize physical phenomena.
Several methods have been introduced with which the position of the magnet wheel of a permanent-magnet-excited synchronous machine can be detected.
One such method is described by M. Schrodl and T. Stefan at pages 48-54 of the Proceedings of the ETG/VDE Conference, entitled "Antriebssysteme Fur Die Gerate und Kraftfahrzeugtechnik" Drive Systems For the Equipment and Automotive Industry!, held in Bad Nauheim, Germany, in 1988. Pages 48-54 of this publication pertain to a chapter entitled "Algorithmus Zur Rechnerischen Erfassung Der Polradlage Einer Permanentmagneterregten Synchronmaschine Ohne Lagegeber" Algorithm for Computer Detection of the Magnet Wheel Position of a Permanent Magnet Excited Synchronous Machine Without Position Transducers!, describe the magnet wheel position being detected in non-salient-pole machines by evaluating an induced voltage. Beyond a certain mechanical rpm, a permanent magnet excited rotor can be used as a position transducer, as a voltage space vector induced in a stator winding generally has an unequivocal relationship with the rotor position sought. Even non-sinusoidal induction distributions in an air gap can be allowed. This induced voltage space vector can be calculated from the terminal voltages, taking resistance and inductive voltage drops into account.
A disadvantage of this system is the fact that the evaluation cannot be done until the machine is beyond a certain minimum rpm, since the induced voltage space vector amount decreases in proportion with the rpm.
An article entitled "Detection of the Rotor Position of a Permanent Magnet Synchronous Machine at Standstill" by M. Schrodl, published in the Proceedings for the International Conference on Electrical Machines in Pisa, Italy in 1986, reports on another method. In this method, electrical measurement signals are measured by varying a magnetic saturation brought about by the permanent magnet. Since this type of measurement can be reproduced, the rotor position can be exactly defined. The knowledge of the polarity of the magnets, which is necessary to carry out the measurement, can be ascertained by varying the magnetic operating point and measuring its effect on the impedance. This makes the investigation of the rotor position possible even with the machine at a standstill. However, this method is very complicated and expensive, due to the necessity of having an additional analog current source.
A dissertation entitled "Die Permanenterregte Umrichtergespeiste Synchronmaschine Ohne Polradgeber Als Drehzahlgeregelter Antrieb" The Permanently Excited Inverter Supplied Synchronous Machine Without Magnet Wheel Transducer As An RPM-Regulated Drive! by H. Vogelmann (University of Karlsruhe, Germany, 1986) discusses a method for locating a magnet wheel position. According to this disclosure, a relatively high-frequency current, generated by an inverter, is superimposed as a test signal on an actual useful signal. The fundamental concept is that an electric alternating signal imposed in a certain direction (space vector) generally causes a reaction in an orthogonal direction, due to different inductances in a longitudinal and transverse axis. Only when the alternating signal is precisely imposed in the longitudinal or transverse direction of the rotor does such coupling not occur. This provides a criterion as to whether or not the signal is being applied in the intended, specified direction.
A prerequisite for attaining an exact measurement is to employ a permanent magnet excited synchronous machine having a salient-pole character. In other words, a synchronous machine must be used having unequal inductances in the longitudinal and transverse directions, as in the case of flux-concentrating arrangements.
However, permanent magnet excited synchronous machines are generally not manufactured in a flux-concentrating version. Rather, they are manufactured using a simple constant air gap in which magnets are glued to the surface of the rotor. Such a construction enables air gap inductions of approximately one Tesla, when high-quality samarium-cobalt (or neodymium-iron) magnets are employed.
Accordingly, the above-discussed locating methods provide usable results only when the machines have a pronounced salient-pole characteristic.
Reluctance machines are distinguished from electrically or magnetically excited synchronous and direct current machines, by their greater sturdiness. In the reluctance machines, if the control algorithms are to be carried out by dynamically high-quality field-oriented or rotor-oriented closed-loop control concepts, it becomes necessary to use a mechanical transducer to detect the rotor position or rotor speed. This requirement reduces the sturdiness of the machine, and increases its cost. As in the case of the other types of rotary field machines, much research work is being directed to replacing the mechanical transducer with mathematical models and/or utilizing physical phenomena.
An article appearing at pages 4-024 to 4-029 of the Proceedings of the EPE--European Power Electronics Conference in Florence, Italy, 1991, entitled "PWM--Based Position Sensorless Control of Variable Reluctance Motor Drives" discusses a sensorless rotor position detection method that can be used with reluctance machines. This method, which can be used only with so-called switched reluctance motors, performs a frequency analysis with a special pulse width modulation control. By dividing voltages and currents prepared by filters and integrators, a conclusion is drawn as to the rotor position dependent inductance of a winding that is carrying current at a particular moment.
However, this method cannot be used with a conventional stator with rotary current windings. Moreover, this method requires both a voltage measurement and a special pulse width modulation.
This same article makes reference to a document (reference 6; entitled "Mutual inductance effects"), which addresses a method in which the rotor position of a reluctance motor is ascertained by means of a supervisory microcontroller. However, this method requires that a voltage measurement be carried out in order to detect the rotor position.
In another article appearing at pages 4-013 to 4-017 of the Proceedings of the EPE--European Power Electronics Conference in Florence, Italy, 1991, entitled "A Torque Angle Calculator for Sensorless Reluctance Motor Drives", a method is proposed for a sensorless rotor position detection in reluctance machines. The point of departure for this method is chosen such that it can be achieved only in the event that all the derivations over time are ignored.
A problem with this method is that it only functions in steady state (or quasi-steady state) operations. Additionally, this method requires that a voltage measurement be performed.
Pages 1-390 to 1-393) of the Proceedings of the EPE--European Power Electronics Conference in Florence, Italy, 1991, entitled "Accurate Sensorless Rotor Position Detection in an SR Motor", discloses a method for making a positional determination of a reluctance motor using test signals. The same method is also described in an article entitled "A New Sensorless Position Detector for SR Drives" published at pages 249-252 of Conference Publication No. 324 of the Fourth International Conference, Power Electronics and Variable Speed Drives, London, 1991. Compared with the methods discussed above, this method has the advantage that it can be used not only with switched reluctance machines, but also with machines having a normal rotary current winding in the stator.
The operating principle of this method is that in an SR motor, there are always motor phases in which there is no operating current flowing for a certain period of time. During that period, a test voltage pulse is impressed. On the one hand, the flux linking of this winding is ascertained by an integration of the test voltage, while on the other hand, the course of current in the winding is measured. If the current reaches a certain value, the instantaneous flux linking is measured, and the corresponding rotor position is ascertained from a table.
However, this method does not function with rotary current windings. Moreover, this method requires the taking of a voltage measurement.
Further, text books disclosing equations for introducing complex quantities based on space vector theory, see, e.g., Kovacs, "Transient Phenomena in Electrical Machines," Elsevier, pp. 14-17 (1984), are well known to the ordinarily skilled artisan, as well as text books disclosing equations in which modulation of an inductance having double the rotor angle is determined, see, e.g., Concordia, "Synchronous Machines," General Electric Series, pp. 10 and 11 (1951).
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to develop a method for determining machine specific electromagnetic and mechanical status variables in electrodynamic rotary field machines by only measuring electrical variables, (especially currents; however, no phase voltages are required, as shown in FIGS. 1-3); and in the process, avoiding the disadvantages or inaccuracies of the known methods described above.
According to an embodiment of the present invention, an induction machine, such as, for example, an asynchronous machine, is magnetized prior to the beginning of a measurement, and feedback from the measurement signals are transferred to the asynchronous machine and measured. The measurement signals comprise voltage discontinuities generated by an inverter which cause current variations that are measured and delivered to a computer to ascertain a complex parameter proportional to the quotient of a stator voltage space vector and a variation over time of a stator current space vector. A direction of the voltage space vector is derived from a known inverter trigger state, hereinafter called a complex parameter, and the magnetic flux is calculated. The complex parameter fluctuates in approximately a sinusoidal fashion in both its real component and its imaginary component, with twice the value of the magnetic flux angle, and twice the value of the magnetic flux angle sought being ascertained by known methods of complex calculation from real and imaginary components.
An advantage of the method of the instant invention resides in it being able to operate at low rpm without the use of a mechanical transducer. The instant invention is not vulnerable to uncertainties in the rotor resistance parameter; accordingly, voltage measurements can be dispensed with. Additionally, the instant invention does not need an additional analog current source. Instead, the already existing supplying inverter is used as the measurement signal generator.
An advantage of the present invention resides in the rotary field machine being embodied as an asynchronous machine.
According to the present invention, a circuit arrangement is provided in which actual current values of the phases of a stator winding of an asynchronous machine are obtained from current measuring devices disposed between an inverter and an asynchronous machine. The measured current values are inputted to a first input of a current detection module. A control output of a priority open-loop controller is connected to a control input of the current detection module. The output of the current detection module is connected to a first input of a current rise computer (i.e., a device for calculating a current change over time) and a field orientation and current regulating module. An output of the current rise computer is connected to a first input of a flux angle computer, while an output of the flux angle computer is connected to a second input of the field orientation and current regulating module. A command torque (or command magnetization) is delivered to a third and fourth input of the field orientation and current regulating module. The output of the field orientation and current regulating module is connected to a first input of a changeover logic circuit, while an output of a timer unit is connected to a second input of the current rise computer, and a third output of a priority controller is connected to an input of an inverter trigger status former and to a second input of a flux angle computer. The output of the inverter trigger status former is connected to a second input of the changeover logic circuit that is triggered by the priority controller. The output of the changeover logic circuit is connected to the input of a triggering module of the inverter.
With this circuit arrangement for a rotary field machine embodied as an asynchronous machine, the method of the present invention can be easily implemented in signal processors and microprocessors or controllers that are available on the market.
A further feature of the circuit arrangement of the present invention resides in that the connection between the flux angle computer and the field orientation and current regulating module is carried via a dynamic asynchronous motor model. The rpm (or load torque) is delivered and integrated from a first and second output, respectively, of the dynamic asynchronous motor model via a first and second line, respectively, to one or more superimposed closed-loop control circuits. The method of the present invention can be integrated into a multi-loop, closed-loop control system, such as, for example, rpm and torque control systems.
The method of the present invention is characterized, for a rotary field machine, in an embodiment as a synchronous machine, in that the determination of the rotor position is effected by means of the known methods of complex calculations by subtraction from two current rise measurements, in which the same voltage space vector is present in both partial measurements, and wherein the stator current space vectors, which are located at the mean during the two partial measurements, must be so different that the stator inductance, because of the different stator currents, perceptibly differs in the process. As a result, the measured difference between two current space vector variation speeds is a complex vector, whose real and imaginary components oscillate at a rotor circumferential speed, so that the argument of this complex vector is an unequivocal relationship with the electrical position of the rotor.
The advantage of the method of the present invention in its use with a synchronous machine resides not only in its great accuracy, but also in that no analog additional current sources are needed for the magnet wheel location. The already existing supplying current converter is used as the measurement signal generator. In this method, ambiguities in terms of the rotor determination are completely precluded.
A further advantageous feature of the present invention pertains to the rotary field machine acting as a synchronous machine.
In the context of the present invention, a circuit arrangement is provided wherein current variations necessary as a result of voltage discontinuities, and for calculating the variation over time of the current space vector amount, are taken from current measuring devices disposed between the current converter and the synchronous machine. Such an arrangement is characterized in that the actual currents from the output of a current detection module are delivered to both a first input of a rotor position computer and a first input of a current tracking device. The torque specification is delivered to a current specification module via a first input, and the output of the current specification module is connected to a second input of the current tracking device. A changeover logic circuit is triggered by a priority controller, a first input of which is connected to the output of the current traction device. The output of the changeover logic is connected to a bridge triggering module, while a second input of the changeover logic circuit is connected to a first output of a measurement signal generator. An input of the current detection module is connected to a third output of the priority controller. A first output of the priority controller is connected to a second input of the current specification module, while the second output of the priority controller is connected to an input of the measurement signal generator. A second output of the measurement signal generator is connected to a second input of the rotor position computer, and the calculated rotor position is made known to a super-imposed closed-loop controller and to the torque specifier from the output of the rotor position computer, via a line.
With the above-described circuit arrangement, the method steps listed above can be attained for a rotary field machine embodied as a synchronous machine.
According to another embodiment of the instant invention, a rotary field machine is embodied as a reluctance machine, in which feedback from measurement signals transferred to the reluctance machine is measured, wherein the measurement signals are voltage discontinuities generated by the inverter, which are either additionally inserted signals or signals that occur during its operation and are suitable for evaluation, and which effect current variations that are measured and delivered to a computer, which ascertains a complex parameter that is proportional (or inversely proportional) to the quotient of the stator voltage space vector and variations over time of the stator current space vector (which is hereinafter referred to as a complex parameter), in which the direction of the voltage space vector is derived from the known inverter trigger state to calculate the rotor position, wherein the complex parameter, because of different reactances in the longitudinal and transverse directions, fluctuates in an approximate sinusoidal fashion in both its real component and its imaginary component, with twice the value of the rotor position angle, and twice the value of the rotor position angle sought being ascertained by known methods of complex calculation from real and imaginary components.
The advantage of the method of the present invention over known methods resides in its application to the reluctance machine, in that no mechanical transducer is necessary, and, voltage measurements can be dispensed with. Additionally, no additional analog current source is needed. Instead, the already existing supplying inverter is used as the measurement signal transducer.
In the context of the present invention, a circuit arrangement is provided in which actual current values of the phases of the stator winding of the reluctance machine are taken from current measuring devices that are disposed between an inverter and a reluctance machine, and which are delivered to first inputs of a current detection module. A control output of a priority open-loop controller is connected to a control input of the current detection module, and an output of the current detection module is connected to a first input of both a current rise computer and a field orientation and current regulating module. The output of the current rise computer is connected to a first input of a rotor position computer, while the output of the rotor position computer is connected to a second input of the field orientation and current regulating module. The command torque or command magnetization is delivered, respectively, to a third and fourth input of the field orientation and current regulating module. The output of the field orientation and current regulating module is connected to a first input of a changeover logic circuit. An output of the timer unit is connected to a second input of the current rise computer. A third output of the priority controller is connected to both an input of an inverter trigger status former and to a second input of the rotor position computer. The output of the inverter trigger status former is connected to a second input of the changeover logic circuit, the changeover logic circuit being triggered by the priority controller. The output of the changeover logic circuit is connected to the input of a triggering module of the inverter.
With such a circuit arrangement, a rotary field machine embodied as a reluctance machine can easily be implemented for signal processors and microprocessors (or micro-controllers) that are available on the market.
The present invention utilizes the state of the art equations for determining complex quantities and for the modulation of inductance with double the rotor angle. That is, by utilizing and manipulating the state of the art equations, the features of the present invention will become more clear. In particular, the electromagnetic state "flux angular position" is obtained by using the new method of measuring the fluctuation of magnetic reactance as a function of flux angular position. This method works well even at zero flux speed and zero mechanical speed which was not possible before. All well-known methods use the back e.m.f. based on flux change per time which vanishes at low speed using these well-known methods. Furthermore, these well-known methods need phase voltage measurement. The method presented here does not use any phase voltage measurement.
First of all, the machine must have detectable inductance differences in space. This is the case if the machine has a salient construction like e.g., reluctance machines or if the machine has saturated parts due to permanent magnetization (or both properties at the same time). In this case, the new mentioned measuring strategy can directly be started independently of armature current level. However, in case the machine has no measurable inductance differences due to a "cylindric rotor" and no flux (hence, no saturation) as given in induction motor case, it is necessary to bring the motor into the desired magnetic set-point by appropriate magnetization.
To provide a magnetizing feature, the present invention recognizes that, due to saturation by means of armature current, detectable inductance differences in space are produced, which can be evaluated. This is done by applying a flux-producing current component to the motor. The magnetic flux which is produced by this current component can be found by the magnetization curve of the motor. The desired current is adjusted by well-known current control loops which use the inverter as a switching voltage source, forcing the current to increase or decrease. Obviously, the varying inductance (or more exactly, the space direction where its minimum value is located) is closely related to the flux axis of the machine. In case of machines with rotors rotating synchronously with flux angular speed as synchronous and reluctance machines, the flux axis is in a fixed angular relation to rotor position.
To provide for ascertaining a complex parameter, the present invention recognizes that the effect of varying inductance is detected by measuring the change of the current (space vector) applied to the motor phases, divided by a quantity proportional to the voltage space vector or vice versa (in order to save calculating time). The direction of the voltage space vector is very exactly defined by the inverter and can be 0, 60, 120, . . . degrees. The modulus of the voltage space vector has no influence on the flux axis calculation (DC link voltage sufficiently constant during the measuring procedure).
Thus, in accordance with the present invention, the basic measuring procedure is as follows. A constant voltage space vector is applied to the machine for a short time period (e.g., voltage space vector in phase axis A is achieved by switching the inverter branch connected to phase A to positive DC link potential and the other branches to negative potential). The time period is typically in the range of 10 to 1000 microseconds depending on the machine inductances and is chosen so as to detect the current change per time with the desired accuracy. On the other hand, the current change is limited to the maximum acceptable deviation of the current from its reference value. To get full current space phasor information, at least (N-1) phase currents are measured (N . . . number of phases) by well-known current measuring devices like e.g., ohmic shunts or similar type devices.
Measuring the phase currents after having started applying the mentioned constant voltage space vector (delay time between voltage switching and current measurement eliminates problems associated with switching transients), storing them, measuring the currents again before the end of the constant voltage space vector and subtracting the second phase values from the first yields phase current changes. Combining these phase current changes using the basic space vector definition (e.g., machine with three phases A,B,C; arbitrary constant value const)
Δi=const(Δi A +Δi B ·exp(j 120°)+Δi A ·exp(j 240°))
yields a complex quantity Δi. Due to the mentioned inductance differences in space, this complex quantity can be mathematically described by (Δi o . . . magnitude of the constant part of Δi; Δi saliency . . . magnitude of the variable part of Δi which is usually considerably smaller than Δi o ; γ ident . . . angular position of minimum inductance which is to be identified; γ u . . . well-known angle of applied voltage space vector):
Δi=(Δi o -Δi saliency ·exp j(2γ ident -2γ u ))·exp jγ u
To provide for the calculation of magnetic flux, the present invention recognizes that dividing Δi by a quantity proportional to the mentioned space vector u (since the modulus of u is not needed for calculation of γ ident , no voltage measurement is necessary) yields an equation for calculating 2γ ident (x . . . complex parameter proportional to the quotient of stator voltage space vector and variation over time of stator current space vector; const . . . arbitrary constant quantity; const2, const3 . . . constant quantities depending on DC link voltage, not explicitly needed for calculation):
Defining
y:=Δi/(const1·u)=x -1
yields
y=Δi/(const2·exp jγ u )=const3(Δi o -Δi saliency ·exp j(2γ ident -2γ u )).
Changing the flux angular position quasi-continuously and repeating the described measuring procedure yields a sinusoidal fluctuation of both real and imaginary part of y with double the desired angle γ ident . For constant DC link voltage and identified Δi o and Δi saliency , γ ident can be calculated by basic mathematical operations from the above equation. The flux axis γ.sub.ψ, (which is closely related to the rotor position γ in the case of permanent magnet synchronous machines and reluctance machines) is calculated from γ ident by (γ corr1 (i torq ), γ corr2 (i torq ) . . . correcting angles, depending on torque-producing current component i torq )
γ.sub.ψ =γ ident +γ corr1 (i torq ) (valid for induction motor, permanent magnet synchronous motor and reluctance motor)
γ=γ ident +γ corr2 (i torq ) (valid for permanent magnet synchronous and reluctance motor)
The correction function γ corr1 (i torq ) is obtained by comparison of γ ident with γ.sub.ψ calculated by a classical flux model (voltage model, current model, . . . ) during a calibrating procedure. The correction function γ corr2 (i torq ) is obtained by comparison of γ ident with γ measured by a position measuring device during a calibrating procedure. These calibrating procedures are done once per machine type at a test-stand and not during regular operation. The correction functions are stored in a look-up table or modeled by an approximating function or neglected.
The necessity of identifying Δi o and Δi saliency as stated above can be neglected by combining at least two measurement with different voltage space vectors. This yields a complex equation (or two real equations after splitting up in real and imaginary parts) from each measurement for calculating γ ident . Hence, by well-known mathematical procedures, Δi o and Δi saliency can be eliminated. As an example, this technique is shown using two measurements (voltage space vectors γ u1 and γ u2 , respectively, current changes Δi 1 and ΔI 2 ):
The first measurement yields the complex quantity y 1 , which is related to γ ident in the following way:
y 1 =Δi 1 /(const2·exp jγ u1 )=const3(Δi o -Δi saliency ·exp j(2γ ident -2γ u1 ))
The second measurement yields
y 2 =Δi 2 /(const2·exp jγ u2 )=const3(Δi o -Δi saliency ·exp j(2γ ident -2γ u2 ))
Splitting up in real and imaginary parts yields four real equations (y:=y real +jy imag ):
y 1real =const3(Δi o -Δi saliency ·cos(2γ ident -2γ u1 ))
γ 1imag =const3(-Δi saliency ·sin(2γ ident -2γ u1 )).
y 2real =const3(Δi o -Δi saliency ·cos(2γ ident -2γ u2 ))
y 2imag =const3(-Δi saliency ·sin(2γ ident -2γ u2 )).
Hence, γ ident can be calculated without explicitly knowing const3, Δi o and Δi saliency .
Using three measurements with three different voltage space vector angles yields 6 real equations with a lot of possibilities of calculating γ ident . Two special cases are using only the real part equations and using only the imaginary part equations, respectively.
With increasing flux angular speed, an error in detecting γ ident will occur due to the increasing e.m.f. influence. This e.m.f. influence is eliminated by using a second measurement (index II), in which the voltage space vector of the second measurement is different from the space vector of the first measurement (index I) (for instance, contrary direction of the voltage space vector of the first measurement: u II =-u I ) or the zero voltage space vector (u II =0, which means inverter state "short circuit", all inverter branches at the same voltage level). The well-known voltage equations for cases I and II are (neglecting stator resistance voltage drop, furthermore both measurements within a short time interval so that the e.m.f. is the same in both measurements)
u I ≈x·Δi I /Δt+u emf
u II ≈x·Δi II /Δt+u emf
Subtracting both equations eliminates the e.m.f. The difference between the space vectors of voltage and current change per time take the place of the respective space vector variables in the individual measurements:
(u I -u II )=x·(Δi I /Δt-Δi II /Δt)
Thus, in accordance with the present invention, the measuring procedure operates independently of e.m.f., and, therefore, of the speed of the machine.
The connection between the rotor position computer and the field orientation and current regulating module is carried via a dynamic reluctance motor model. The rpm (or load torque) is delivered and integrated from a first and second output, respectively, of the dynamic reluctance motor model via a first and second line, respectively, to one or more super-imposed closed-loop control circuits.
Hence the method of the invention can be integrated into a multiple-loop closed-loop control system, such as rpm and torque control systems.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of the preferred embodiments as illustrated in the accompanying drawings in which reference characters refer to the same parts throughout the various views, and wherein:
FIG. 1 illustrates the present invention applied to an asynchronous machine;
FIG. 2 illustrates the present invention applied to a synchronous machine; and
FIG. 3 illustrates the present invention applied to a reluctance machine.
DETAILED DESCRIPTION OF THE EMBODIMENTS
The invention will now be described in further detail, referring to several exemplary embodiments. The principle of the invention is disclosed in FIG. 1 with an asynchronous machine, FIG. 2 with a synchronous machine, and in FIG. 3 with a reluctance machine.
The method of the present invention will be explained in detail with reference in FIG. 1, which illustrates a three-phase asynchronous machine. The principle of the present invention can be employed in the same way for asynchronous machines having a different number of phases.
FIG. 1 illustrates three leads 18, 19, 20 of a rotary current line, which are carried to a voltage intermediate-circuit inverter 1 that powers an asynchronous machine 2. Current measuring devices 3 are associated with the supply lines and are located between the voltage intermediate-circuit inverter 1 and the asynchronous machine 2. Using a current detection module (module that measures current) 4 and including a priority open-loop control (super-imposed control module) 5 that performs handles timing issues, the current measuring devices 3 provide an updated current space vector, which, using a timer unit 10, enables a current variation space vector to be ascertained by a current rise computer (module that calculates a current change over time) 6. This vector, together with voltage space vector direction information generated by the priority controller 5, is used by a flux angle computer (device that calculates a flux angular position) 8 to calculate a flux angle that is used by a field orientation and current regulating block (unit that provides a field-orientation and current control) 7, which has "command torque" and "command magnetization" inputs, for ascertaining the converter triggering state.
Moreover, the flux angle ascertained by the flux angle computer 8 can be integrated into super-imposed closed-loop control circuits (for instance, rpm and torque control circuits). The priority controller 5 decides whether inverter triggering, in the case where the flux angle determination algorithm is carried out, is accomplished in a changeover logic circuit (switching circuit) 9 of a voltage space vector former (module that provides an inverter switching state command) 11, or in the normal current regulating instance, by the field orientation and current regulating module 7.
According to the embodiment illustrated in FIG. 1, the output of the current detection module 4 delivers generally digitalized information (which is either phase current or stator-specific components of the current space vector) representing current space vector to the scanning moments, wherein the scanning moments are defined by a signal outputted from the priority controller 5 and input to the current detection module 4. The information output from the current detection module 4 determines the current variation space vector or the variables representing the latter, in the current rise computer 6 by means of a time interval delivered by the timer unit 10, that is controlled by a signal output from the priority controller 5. In the present invention, the priority controller 5 controls a measurement cycle in response to module 11 that provides an inverter switching state command. In response to a signal outputted from the priority controller 5 to the switching changeover logic circuit 9, the inverter switching state module 11 is connected to the inverter triggering module 12 of the inverter 1. The trigger status module (inverter switching state module) 11 is controlled by the priority controller 5 and produces measurement signals that are assigned directly by the inverter 1 to the voltage space vector connected to the asynchronous machine 2.
The voltage space vector information, along with a current variation space vector outputted from dynamic asynchronous motor module 13, is used to determine a flux angle in the flux angle module 8. The dynamic asynchronous motor model 13 is based upon a mathematical simulation of an asynchronous machine according to known methods. The dynamic asynchronous motor model 13 also simultaneously determines the rpm speed of the machine 2 on line 16 and a load torque on line 17. Then, the flux angle is used in the current regulating module 7 to calculate an operational inverter trigger status in accordance with known field oriented regulation rules by means of nominal torque values inputted via line 14 and flux value inputted via line 15. By utilizing actual current information output by the current detection module 4 and inputted to a second input of the current regulating module 7, an inverter-trigger status is output from the current regulating module 7 to a second input of the changeover logic circuit 9 to be supplied to the triggering module 12 of the inverter 1.
Since the total of the currents delivered to the asynchronous machine must be zero, one current measuring device 3 can be dispensed with.
FIG. 2 illustrates the present invention applied to a three-phase synchronous machine. However, the invention can be used with synchronous machines having different number of phases. As shown in FIG. 2, synchronous machine 102 is supplied via a voltage intermediate-circuit inverter 101 by three rotary current lines 114, 115, 116, in which the phase currents are detected by three current measuring devices 103. However, it is also sufficient for only two phase currents to be measured, since the total current must be zero.
A current detection module (module for measuring current flow) 104 is controlled by a priority controller 105 and furnishes the actual currents at the measuring moments. Together with command currents generated by a current specification module (module for calculating a current reference value) 107, the actual currents are processed in a current rise computer (device for calculating a current change over time) 106 and furnish a bridge trigger signal. The current specification module 107 receives its input values via line 113 from a torque specifier (not shown) and is controlled by a priority controller 105. During a measurement with test cycles, the priority controller 105 activates a measurement signal generator 108, which, via changeover logic circuit (switching circuit) 110, services the priority controller 105, and delivers the bridge trigger signal to a bridge triggering module (Module that generates an inverter firing signal) 111.
In this case, the bridge trigger signal generated by the current rise computer 106 becomes inoperative. A rotor position computer (module for calculating a rotor angular position) 109 uses actual currents furnished by the current detection module 104 and the alternating converter switching state furnished by the measurement signal generator 108 to calculate the rotor position, which is passed on to a torque specifier and to the priority closed-loop controllers, via line 112.
Thus, the current detection module 104 measures actual currents detected by the current measuring devices at moments which are predetermined by a digital signal inputted to the current detection module 104 from the priority controller 105. An output of the current detection module 104 represents actual currents (which are generally digitalized) either in the form of phase currents or in the form of stator-specific phase current-space vector components. The input of line (113) represents the operational nominal current value of a superimposed rpm or torque control/adjustment.
A digital control signal is inputted to current specification module 107 to instruct when a measurement procedure is taking place and an operational nominal current value is out of power. An output of the current specification module 107 represents a nominal current that is inputted to one input of the current traction device 106 to be compared to actual values in the current traction device 106 inputted to a second input of the current traction device 106 via the current detection module 104. By means of a current regulator, 3-bit inverter-trigger information is obtained from the difference of the comparison, and connected to the inverter triggering module via the changeover logic circuit 110 that is controlled by the priority controller 105.
Priority controller 105 generates the current measuring command that is supplied to the current detection module 104. Additionally, the priority controller 105 is connected to the measurement signal generator 108 and the current specification module 107.
The measurement signal generator 108 outputs a signal that is connected to a second input terminal of the inverter triggering module 111 via the changeover logic circuit 110, which, as noted above, is controlled by the priority controller 105. The rotor position module 109 receives inverter-trigger information (which represents a voltage space vector) that is output from the measurement signal generator 108 and an output of the current detection module 104 to calculate the actual rotor position, which is output on line 112.
The method of the invention will now be explained with reference to a three-phase reluctance machine illustrated in FIG. 3. However, the present invention can be applied to a reluctance machines having any number of phases.
FIG. 3 shows three leads 218, 219, 220 of a rotary current line which are carried to a voltage intermediate-circuit inverter 201 that powers reluctance machine 2. Current measuring devices 203 are provided in the supply lines between the voltage intermediate-circuit inverter 201 and a reluctance machine 202. With a current detection module 204 and including a priority open-loop control (super-imposed control module) 205 that performs a timing operation, the current measuring devices 203 provide an updated current space vector. Using a timing unit 210, the current variation space vector is ascertained by a current rise computer (unit that calculates a current change over time) 206. This vector, together with the voltage space vector direction information generated by the priority controller 205, is used by a rotor position computer (unit for calculating a flux angular position) 208 to calculate the rotor position angle used by a field orientation and current regulating block 207, which has a "command torque" and "command magnetization" inputs, for ascertaining a converter triggering state.
Moreover, the rotor position angle ascertained by the rotor position computer 208 can be integrated into super-imposed closed-loop control circuits (for instance, rpm and torque control circuits). The priority controller 205 decides whether the inverter triggering, in the case where the rotor position angle determination algorithm according to the invention is carried out, is accomplished in a changeover logic circuit (switching unit) 209 of the voltage space vector former (module that provides an inverter switching state command) 211, or in the normal current regulating instance, by the field orientation and current regulating module 207.
Alternatively, the changeover device 209 and the voltage space vector former 211 can be replaced by a feedback circuit that transmits the actual triggering state to the rotor position computer 208. In this case, the output of the field orientation and current regulating module 207 serves as the input to the triggering module (module that generates an inverter firing signal) 212.
According to the embodiment of FIG. 3, an output signal of the current detection module 204 supplies generally digitalized information (either phase currents or stator-specific components of the voltage space) representing the current space vector of the scanning moments to the input of the current rise computer 206 and one input of the current regulating module 207, wherein scanning moments are defined by a digital signal output from the priority controller 205 and inputted to the current detection module 204. The information output by the current detection module 204 is used to determine a current variation space vector or representative variables thereof in the current rise computer 206 by means of a time interval that is supplied by the timer unit 210. The timer unit 210 is controlled by a signal outputted by the priority controller 205. A measurement cycle is controlled by the priority controller 205 using the inverter trigger status module 211, which is supplied, via the switching changeover logic circuit 209, to the inverter triggering module 212 of the inverter 201. The inverter trigger status module 211 produces measurement signals that are directly assigned to the asynchronous machine 202 by the inverter 201. The voltage space phase information (outputted by the priority controller 205 to the flux angle computer 208) and the signal exchanged between the current rise computer 206 and the flux angle computer 208 (which represents the current variation space), are optimally improved in a dynamic reluctance model 213 by mathematically simulating a reluctance machine in accordance with known methods. The dynamic reluctance model produces a flux angle signal that is supplied to one input of the current regulating module 207.
In accordance with the simulation, the reluctance motor model 213 also outputs a signal representing the rpm of the machine on line 216 and a signal representing the load torque on line 217. The flux angle signal, and the actual current information outputted from the current detection module 204 and inputted to a second input of the current regulating module 207, is used by the current regulating module 207 to calculate the operational inverter trigger status as per known rules of field oriented regulations using nominal rpm values inputted via line 214 and flux values inputted via line 215. The inverter trigger status is then transmitted to the triggering module 212 of the inverter 201 via the changeover logic circuit 209, the operation of which is controlled by the priority controller 205.
Finally, since the total of the currents delivered to the reluctance machine is always zero, one current measuring device 203 can be dispensed with. | Method and apparatus for accurately determining electromagnetic and mechanical information from electrodynamic rotary field machines, such as, for example, asynchronous, synchronous or reluctance machines that utilize voltage discontinuities generated by an associated inverter. The apparatus according to the present invention obtains information from machines running at a low rpm without using a mechanical transducer, as well as with machines running at a high rpm. | 7 |
BACKGROUND OF THE INVENTION
1. Field of invention
The present invention relates to an improved apparatus for measuring the circulating blood volume.
2. Related Art
The circulating blood volume is an important piece of biological information for medical diagnosis. This has conventionally been measured by a method that comprises injecting a dye that is slow in clearing from blood vessels, taking a blood sample at the point of time when the dye has been distributed uniformly throughout the blood in the whole body, measuring the dye density in the blood, and calculating the circulating blood volume from the measured dye concentration.
This method, however, has had two major disadvantages. First, it requires lots of steps and time to perform one cycle of measurement. Second, the residual dye in blood precludes frequent measurements. If a fast dye is used that is cleared rapidly out of the blood vessels, it is necessary to perform frequent post-injection blood sampling and a corresponding number of measurements must be made to know the dye concentration in the blood samples. Furthermore, the precision of measurements depends on the frequency of blood sampling. Because of these limitations, the use of fast dyes is by no means a practical approach.
The recent advances in electronics have made it possible to achieve noninvasive, continuous and precise measurements of dye concentration in blood by applying the principle of pulse oximetry, in which the ratio between the density of two light absorbers in arterial blood is determined on the basis of the pulsation of light transmitted through a living tissue. To measure the dye density in the blood by this method, the ratio between the densities of hemoglobin and an injected dye is first determined and then multiplied by the separately measured hemoglobin in the blood to determine the absolute value of dye density in arterial blood. The dye dilution curve, or the time-dependent changes in the absolute value of the dye density, has a definite straight line when expressed in a semi-logarithmic graph. Extrapolating this straight line to the dye injection time gives a dye density in the blood that would be obtained if the dye were distributed uniformly in total blood without being cleared from blood vessels. The thus determined dye density is named its initial dye density. Dividing the amount of the injected dye by its initial density will give circulating blood volume.
This method provides for frequent repetitions of measurement by injection of a dye that has only a short lifetime in blood. This method also enables the measurement of the clearing ability of an organ that performs selective excretion of the dye used or the blood flow in that organ.
However, this method which relies upon the principle of pulse oximetry is not free from problems. To meet the need for measuring the light transmitted through a living tissue, the site of measurement is limited to peripheral such as an earlobe or a fingertip. Further, the dye injection site is often peripheral such as an antecubital vein and, hence, it takes a long time for the injected dye to travel from the injection site to the site of measurement. The length of this time is particularly long if massive bleeding occurs to reduce the circulating blood volume. If, under such circumstances, the straight line obtained by logarithmic transformation of the dye dilution curve is extrapolated to the injection time, the measured initial dye density will differ greatly from the actual value, creating a substantial error in measurement. With a view to eliminating this error, Haneda et al. proposed in 1986 a method for extrapolation to the dye appearance time T a (Tohoku Journal of Experimental Medicine 1986, 148 page 49-56 "A method for measurement of Total circulating blood volume using indocyanine green"). This method enables elimination of the error dependent difference in the lapse of time from T 0 (dye injection time) to T a (dye appearance time). For instance, the injected dye will appear after the lapse of 5 to 10 seconds when measurement is conducted at an earlobe whereas a time of 10 seconds to 2 minutes lapses when measurement is conducted at a fingertip. Nevertheless, the dye injected into the blood will mix with the blood and diffuse both forward and backward of that portion of blood. Hence, the most rapidly advancing portion of the dye injected concentration will advance ahead of the center of the injected dye concentration as it approaches a measuring site. This phenomenon is pronounced if the peripheral blood circulation is inefficient and the time from T a to the time which is the center of the population of dye appears will sometimes be as great as 30 seconds or more if measurement is conducted at a fingertip. Thus, great errors have occasionally occurred even if extrapolation to the dye appearance time T a is made.
SUMMARY OF THE INVENTION
An object, therefore, of the present invention is to solve the aforementioned problem with the conventional practice of injecting a fast dye into a blood vessel, measuring continuously the dye density on the basis of continuous measurement of pulsation of transmitted light through a living tissue, and calculating the circulating blood volume from the time-dependent changes in the measured dye density in the blood, the problem being such that an error in measurement occurs if the exponential decay portion of the dye dilution curve is extrapolated to either the dye injection time or the dye appearance time.
The invention relates to an apparatus for measuring the circulating blood volume by injecting a predetermined amount of dye into a blood vessel in the human body, measuring the dye density in the blood continuously on the basis of continuous measurement of pulsation of transmitted light through a living tissue, and calculating the circulating blood volume from the measured dye density in the blood, comprising:
dye density measuring means for measuring the dye density in the blood continuously;
mean transit time detecting means for determining the mean transit time from the result of measurement with said dye density measuring means;
interval determining means for determining an interval for regression line calculation from the point of time as determined by said mean transit time detecting means;
logarithmic transformational means for performing logarithmic transformation of the dye density as measured by said dye density measuring means;
regression line calculating means by which a regression line for the curve that represents the relationship between the logarithm of the dye density as determined by said logarithmic transformational means and the time of measurement is determined for the interval as determined by said interval determining means;
initial dye density calculating means for determining the initial dye density by extrapolating the thus determined regression line to the point of mean transit time; and
circulating blood volume calculating means for determining the circulating blood volume by dividing the amount of injected dye by the dye density as determined by said initial dye density calculating means.
In the apparatus of the present invention, the mean transit time detecting means is replaced by peak time detecting means that determines the time at which the dye density as measured by said dye density measuring means becomes maximal, and the initial density calculating means is replaced by means that determines the initial dye density by extrapolating the calculated regression line to the time at which the dye density becomes maximal.
In the apparatus of the present invention, the logarithmic transformational means is eliminated and the interval determining means, the regression line calculating means and the initial dye density calculating means are replaced respectively by the following: interval determining means for determining an interval for exponential regression curve calculation from the point of time as determined by said mean transit time detecting means; exponential regression curve calculating means by which an exponential regression curve for the curve that represents the relationship between the dye density as measured by said dye density measuring means and the time of measurement is determined for the interval as determined by said interval determining means; and initial dye density calculating means that determines the initial dye density by extrapolating the thus calculated exponential regression curve to the point of mean transit time.
In the apparatus of the present invention, the logarithmic transformational means is eliminated and the mean transit time determining means, the interval determining means, the regression line calculating means and the initial dye density calculating means are replaced respectively by the following: peak time detecting means that determines the time at which the dye density as measured by said dye density measuring means becomes maximal; interval determining means for determining an interval for exponential regression curve calculation from the point of time as determined by said peak time detecting means; exponential regression curve calculating means by which an exponential regression curve for the curve that represents the relationship between the dye density as measured by said dye density measuring means and the time of measurement is determined for the interval as determined by said interval determining means; and initial dye density calculating means that determines the initial dye density by extrapolating the thus calculated exponential regression curve to the time at which the dye concentration becomes maximal.
According to the present invention, the dye density measuring means performs continuous measurement of the dye density of the injected dye. The result of this continuous measurement is used by the mean transit time detecting means to determine the mean transit time. The interval determining means determines an interval for regression line calculation from the time as determined by the mean transit time determining means. The regression line calculating means determines, for the interval as determined by said interval determining means, a regression line for the curve that represents the relationship between the logarithm of the dye density as determined by the logarithmic transformational means and the time of measurement. The initial dye density calculating means extrapolates the thus determined regression line to the point of mean transit time and determines the dye density at the mean transit time T m , or the time taken from the dye injection time T 0 until the mean transit time (hereunder abbreviate as MTT) of the initial circulating part of the dye has lapsed. In other words, MTT is the time taken from the injection of the dye at a given site to the time at which one half the total quantity of the dye has passed the site of measurement. The circulatory blood volume calculating means determines the circulating blood volume by dividing the amount of injected dye by the dye density as determined by said initial dye density calculating means.
According to the present invention, the dye density measuring means performs continuous measurement of the density of the injected dye. The result of this continuous measurement is used by the peak time detecting means to determine the time at which the measured dye density becomes maximal. The interval determining means determines an interval for regression line calculation from the time as determined by the peak time detecting means. The regression line calculating means determines, for the interval as determined by said interval determining means, a regression line for the curve that represents the relationship between the logarithm as determined by the logarithmic transformational means and the time of measurement. The initial dye density calculating means extrapolates the thus determined regression line to the time at which the dye density becomes maximal. The circulating blood volume calculating means determines the circulating blood volume by dividing the amount of injected dye by the dye density as determined by said initial dye density calculating means.
According to the present invention, the dye density level measuring means performs continuous measurement of the density of the injected dye. The result of this continuous measurement is used by the mean transit time detecting means to determine the mean transit time. The interval determining means determines an interval for exponential regression curve calculation from the thus determined mean transit time. The exponential regression curve calculating means determines, for the interval as determined by said interval determining means, an exponential regression curve for the curve that represents the relationship between the dye density as measured by the dye density measuring means and the time of measurement. The initial dye density calculating means extrapolates the thus determined regression exponential curve to the point of mean transit time. The circulating blood volume calculating means determines the circulating blood volume by dividing the amount of injected dye by the dye density as determined by said initial dye density calculating means.
According to the present invention, the dye density measuring means performs continuous measurement of the density of the injected dye. The result of this continuous measurement is used by the peak time detecting means to determine the time at which the measured dye concentration becomes maximal. The interval determining means determines an interval for exponential regression curve calculation from the thus determined peak time. The exponential regression curve calculating means determines, for the interval as determined by said interval determining means, an exponential regression curve for the curve that represents the relationship between the dye density as measured by the dye density measuring means and the time of measurement. The initial dye density calculating means extrapolates the thus determined exponential regression curve to the time at which the dye density becomes maximal. The circulating blood volume calculating means determines the circulating blood volume by dividing the amount of injected dye by the dye density as determined by said initial dye density calculating means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowchart illustrating the operational sequence of an apparatus according to the first embodiment of the invention;
FIG. 2 is a block diagram showing the general configuration of the apparatus according to the first embodiment of the invention;
FIG. 3 is a diagram showing how the apparatus according to the first embodiment of the invention is used;
FIG. 4 is a graph showing the dye density vs time relationship as measured with the apparatus according to the first embodiment of the invention;
FIG. 5 is a graph showing the logarithm of dye density vs time relationship as measured with the apparatus according to the first embodiment of the invention;
FIG. 6 is a flowchart illustrating the operational sequence of an apparatus according to the second embodiment of the invention;
FIG. 7 is a flowchart illustrating the operational sequence of an apparatus according to the third embodiment of the invention; and
FIG. 8 is a flowchart illustrating the operational sequence of an apparatus according to the fourth embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 is a block diagram showing the general configuration of a system according to the first embodiment of the invention. A light-emitting portion 1 consists of two LEDs 2 and 3 that emit light at two different wavelengths, and a drive circuit 4 for driving these LEDs. Assume that LED 2 emits light at wavelength λ 1 whereas LED 3 emits light at wavelength λ 2 . A light-receiving portion 5 consists of a photodiode 6 placed in a face-to-face relationship with LEDs 2 and 3, a current-voltage converter 7 which converts the output current of the photodiode 6 to a voltage signal, and an amplifier 8. A multiplexer 9 is a circuit that receives a signal from the amplifier 8 and supplies it alternately to filters 10 and 11. A multiplexer 12 is a circuit that receives the outputs of filters 10 and 11 and alternately supplies them to an A/D converter 13. The A/D converter 13 is a circuit that receives an analog signal from the multiplexer 12 and converts it to a digital signal. A CPU 14 is a circuit that not only controls the drive circuit 4 and multiplexers 9 and 12 by means of control signals but also performs computations on the basis of the signal from the A/D converter 13, thereby determining the circulating blood volume. A memory 15 is a circuit that not only contains the program set forth in FIG. 1 but also stores the data that are supplied from CPU 14. CPU 14 will execute the program contained in the memory 15. A display portion 22A will display the data that are supplied from CPU 14. An input portion 22B consists of a plurality of switches and keys that are touched by the operator to produce associated input signals that are fed into CPU 14.
FIG. 3 shows how the apparatus according to the first embodiment of the invention is used. The probe 20 of the apparatus is fitted on an earlobe 26 of a subject. The probe 20 has a clip 20A comprising two opposing grippers. One gripper is fitted with LEDs 2 and 3 (see FIG. 2) and the other gripper is fitted with photodiode 6 also shown in FIG. 2. As one can see from FIG. 2, the light emitted from LEDs 2 and 3 will pass through the earlobe 26 to be launched into the photodiode 6. As shown in FIG. 3, LEDs 2 and 3 and photodiode 6 are connected to the main unit 22 of the apparatus via a lead wire 21. The main unit 22 has the display portion 22A and the input portion 22B exposed on the surface.
The apparatus shown in FIGS. 2 and 3 will operate in the following manner. When the operator switches the power on, CPU 14 will output control signals to the drive circuit 4 and multiplexers 9 and 12, respectively. The drive circuit 4 alternately turns on and off the LEDs 2 and 3 for predetermined periods of time. Multiplexer 9 will supply the output of amplifier 8 to filter 10 while LED 2 is on and it supplies said output to filter 11 while LED 3 is on. Filters 10 and 11 eliminate the noise in the signals from light having wavelengths λ 1 and λ 2 , respectively. The multiplexer 12 alternately supplies the noise-free signals to the A/D converter 13, which digitizes those signals before they enter the CPU 14. The operator injects a dye such as ICG (indocyanine green) from a syringe 23 (see FIG. 3) into the subject at a peripheral site, say, an antecubital vein via a conduit 24 and a catheter 25. Simultaneously with the dye injection, the operator touches a relevant switch to signal the injection start time to CPU 14.
The subsequent procedure will now be described with reference to the flowchart shown in FIG. 1. In step 101a, CPU 14 calculates C g , or the dye density of ICG in the blood, on the basis of the signal supplied from the A/D converter 13. Calculation of C g is performed in accordance with the following equation (A):
C.sub.g = log{I.sub.λ1 /(I.sub.80 1 -ΔI.sub.λ1)}/log{I.sub.λ2 /(I.sub.λ2 -ΔI.sub.λ2)}-(K.sub.1 /K.sub.2)!·(K.sub.2 /K.sub.3)·K.sub.4 (A)
where I 80 1 is the quantity of transmitted light at wavelength λ 1 and I.sub.λ2 is the quantity of transmitted light at wavelength λ 2 , and both are the values of the signals supplied from A/D converter 13 to CPU 14; ΔI.sub.λ1 and ΔI.sub.λ2 are the values that are determined from the changes in I.sub.λ1 and I.sub.λ2, respectively, and which are detected with CPU 14; K 1 , K 2 , K 3 and K 4 are the values that are loaded in CPU 14 and which are adjustable by key entry.
Equation (A) is used in the invention for the following reasons.
First, the Lambert-Beer law states that the following equation holds in the case where a dye-containing substance is illuminated with light:
E·C·D=log(Iin/I) (1)
where E is the extinction coefficient of the dye; C is the density of the dye; D is the thickness of the dye-containing substance; I in is the quantity of incident light; and I is the quantity of transmitted light.
The relationship expressed by equation (1) is valid as an approximation for a light-scattering substance such as blood and the error that may occur will not affect the essence of the present invention. Therefore, the following discussion presupposes the validity of equation (1). When a living tissue containing a pulsating blood flow is illuminated with light, the following equation will hold (the suffix b refers to the blood layer and the suffix t to the tissue layer excepting the blood layer):
E.sub.b ·C.sub.b ·D.sub.b +E.sub.t ·C.sub.t ·E.sub.t =log(Iin/I) (2)
If the thickness of the blood layer D b increases by ΔD b due to pulsation, the quantity of transmitted light will decrease by ΔI; hence, the following equation holds:
E.sub.b ·C.sub.b ·(D.sub.b +ΔD.sub.b)+E.sub.t ·C.sub.t ·D.sub.t =log{Iin/(I-ΔI)}(3)
Subtracting eq. (2) from eq. (3), we get:
E.sub.b ·C.sub.b ·ΔD.sub.b =log{I/(I-ΔI)}(4)
If the blood contains the injected dye, the following equation will hold:
E.sub.b ·C.sub.b ·ΔD.sub.b ⃡E.sub.g ·C.sub.g ·ΔD.sub.b =log{I/(I-ΔI)}(5)
where E b is the extinction coefficient of the blood; C b is the density of hemoglobin (light absorption by the blood is due to the hemoglobin in blood); E g is the extinction coefficient of the injected dye; and C g is the density of the injected dye.
If the light having wavelength λ 1 is absorbed by both the blood and the injected dye as in the case where λ 1 is 805 nm, eq. (5) is rewritten as:
E.sub.bλ1 ·C.sub.b ·ΔD.sub.b +E.sub.gλ1 ·C.sub.g ·ΔD.sub.b =log{I.sub.λ1 /(I.sub.λ1 -ΔI.sub.λ1)}(6)
If the light having wavelength λ 2 is absorbed by the blood but not by the injected dye as in the case where λ 2 is 900 nm, eq. (5) is rewritten as:
E.sub.bλ2 ·C.sub.b ·ΔD.sub.b =log{I.sub.λ2 /(I.sub.λ2 -ΔI.sub.λ2)}(7)
Combining eqs. (6) and (7), we get:
(E.sub.bλ1 /E.sub.bλ2)+(E.sub.gλ1 /E.sub.bλ2)·(C.sub.g /C.sub.b)=log{I.sub.λ1 /(I.sub.λ1 -ΔI.sub.λ1)}/log{I.sub.λ2 /(I.sub.λ2 -ΔI.sub.λ2)} (8)
Hence, C g is expressed by:
C.sub.g = log{I.sub.λ1 /(I.sub.80 1 -ΔI.sub.λ1)}/log{I.sub.λ2 /(I.sub.λ2 -ΔI.sub.λ2)}-(E.sub.bλ1 /E.sub.bλ2)!·(E.sub.bλ2 /E.sub.gλ1)·C.sub.b (9)
Since C b is substantially invariable using the measurement of a dilution curve for the injected dye, it may well be considered as constant and a premeasured value can be substituted. As for E b λ1 and E b λ2, the effect of the oxygen saturation is negligible, so values for 100% oxygen saturation (which are known) may be substituted. E g λ1 is predetermined for the specific dye to be used and hence is known. With these values stored in memory, ΔI.sub.λ1 and ΔI.sub.λ2 are determined from the measured values of I.sub.λ1 and I.sub.λ2. Substituting all relevant values into eq. (9), we get a dye dilution curve plotting the time-dependent values of C g . Thus, K 1 , K 2 , K 3 and K 4 in eq. (A) are E b λ1, E b λ2, E g λ1 and C b , respectively. For each occurrence of pulsation, CPU 14 determines ΔI.sub.λ1 and ΔI.sub.λ2 and calculates eq. (A). This procedure gives a dye dilution curve, or the continuum of varying values of C g . Each time it gets the value of C g , CPU 14 also determines its logarithm by calculation. This step of logarithmic transformation is labelled step 101b in FIG. 1. CPU 14 loads memory 15 with data on the thus determined two kinds of dye dilution curve (one representing the relationship between C g and time t and the other representing the relationship between log C g and time t).
Processing with CPU 14 proceeds to step 102 for calculating the mean transit time MTT by the following procedure. First, an initial circulation curve is determined using the C g -t curve (see FIG. 4) which is stored in memory 15. To this end, two points on the C g -t curve are selected, one at 80% of the first peak value and the other at 40% of the peak value; then, an exponential attenuation curve is drawn that passes through these two points. The thus determined exponential curve is combined with a C g -t curve starting at zero C g past the first peak and ending at 80% of that peak value, thereby constructing the initial circulation curve. In the next step, the total area defined by this initial circulation curve and the t-axis is determined and bisected by a straight line parallel to the C g -axis; the point at which this straight line crosses the t-axis represents the MTT and the value of t at that point is named T m .
Processing with CPU 14 then proceeds to step 103 for determining an interval for calculating a regression line for the log C g -t curve (see FIG. 5) which is also stored in memory 15. The interval to be calculated is defined by two points of time t, one at 2.5 min after the T m which has been determined in step 102 and the other at 5.5 min after the T m . Thus, CPU 14 calculates both T m +2.5 (min) and T m +5.5 (min) and holds the result of calculation.
Processing with CPU 14 progresses to step 104 for calculating a regression line based on the interval data that have been determined in previous step 103. Stated more specifically, the line of regression is expressed by log C g =at+b (see FIG. 5) and the coefficients a and b are determined by the method of least squares.
Processing with CPU 14 then goes to step 105 for calculating the initial dye density. Stated more specifically, the regression line that has been determined in step 104 is extrapolated to the time T m and log C g0 , or the value of log C g at T m , is determined. The inverse log of this value is C g0 .
Processing with CPU 14 proceeds to step 106 for calculating the circulating blood volume. In this step, the amount of injected dye is divided by C g0 which has been determined in step 105. The amount of injected dye was preliminarily supplied to and held by CPU 14 before the process started. As a result of this final step, the circulating blood volume is determined and displayed in the display portion 22A.
In accordance with the first embodiment of the invention described above, MTT is determined from the total area of the initial circulation curve and this gives the correct value of MTT.
After MTT is thus determined, extrapolation to the mean transit time T m is made to determine the initial dye concentration, which is further processed to determine the circulating blood volume. Determining the time T m in this method requires that the correct value of the mean transit time MTT be obtained. To this end, the initial circulating portion of the dye has to be isolated correctly from the dye density diagram. However, if the peripheral blood circulation is inefficient, the injected dye will be diffused in both forward and backward directions and the overlap between the density waveforms of the initial and recirculating portions of the dye will sometimes introduce difficulty into the operation of isolating the initial circulating portion by calculation. In a case like this, extrapolation may be effected to the peak density time T p which substantially coincides with the time T m .
Thus, the second embodiment of the invention relates to an apparatus in which the time T m is replaced by the peak density time T p , or the point of time at which the dye dilution curve assumes a peak value. The composition of the apparatus according to the second embodiment is essentially the same as that of the apparatus according to the first embodiment, except that CPU 14 performs processing according to the flowchart shown in FIG. 6. Steps 101a, 101b and 106 in this flowchart are identical to the corresponding steps in the flowchart shown in FIG. 1 and, hence, need not be described. In step 102A, CPU 14 determines T p (the time at which C g peaks) from the C g -t curve stored in memory 15. In step 103A, CPU 14 determines two points of time at which two predetermined periods of time lapse from T p , thereby determining an interval for regression line calculation. In step 104A, CPU 14 determines, for the thus determined interval, a regression line for the log C g -t curve by calculation. In step 105A, CPU 14 extrapolates the thus determined regression line to T p , determines log C g0 (the value of log C g at T p ), and calculates C g0 , the inverse log of log C g0 .
The apparatus according to the second embodiment is more error prone than the apparatus according to the first embodiment but can be substituted for the latter in the case where the initial circulating portion of the dye dilution curve is not clearly distinguishable from the recirculating portion.
In the two embodiments described above, the dye density in the blood is transformed to its logarithm and a regression line is calculated for the logarithmic data. In the third embodiment of the invention, the dye density in the blood is not transformed to the logarithm but an exponential regression curve is calculated from the C g -t curve. Then, the initial dye concentration C g0 is determined from the calculated curve and the circulating blood volume is determined from the C g0 . An apparatus according to this third embodiment will now be described. The configuration of this apparatus is essentially the same as that of the apparatus according to the first embodiment, except that CPU 14 performs processing according to the flowchart shown in FIG. 7. Steps 101a and 106 in this flowchart are identical to the corresponding steps in the flowchart shown in FIG. 1 and, hence, need not be described. Without performing logarithmic transformation of C g , the embodiment under consideration does not involve a step corresponding to step 101b shown in FIG. 1. In step 102B, CPU 14 determines the time T m . In step 103B, CPU determines two points of time at which two predetermined periods of time elapse from T m , thereby determining an exponential regression curve. In step 104B, CPU 14 determines, for the thus determined interval, an exponential regression curve for the C g -t curve by calculation. In step 105B, CPU 14 extrapolates the thus determined exponential regression curve to T m and determines C g0 , or the value of C g at T m .
The fourth embodiment of the invention will now be described. The configuration of an apparatus according to this fourth embodiment is essentially the same as that of the apparatus according to the first embodiment, except that CPU 14 performs processing according to the flowchart shown in FIG. 8. Steps 101a and 106 in this flowchart are identical to the corresponding steps in the flowchart shown in FIG. 1 and, hence, need not be described. Without performing logarithmic transformation of C g , the embodiment under consideration does not involve a step corresponding to step 101b shown in FIG. 1. In step 102C, CPU 14 determines T p (the time at which C g peaks) from the C g -t curve stored in memory 15. In step 103C, CPU 14 determines two points of time at which two predetermined periods of time lapse from T p , thereby determining an interval for exponential regression curve calculation. In step 104C, CPU 14 determines, for the thus determined interval, an exponential regression curve for the C g -t curve by calculation. In step 105C, CPU 14 extrapolates the thus determined regression line to T p and determines C g0 , or the value of C g at T p .
The dye that is injected into blood in the four embodiments described above is ICG which is specifically cleared from the liver. It should, however, be noted that dyes that are specifically cleared from other internal organs such as kidneys may be used and similar results can be attained by performing similar processing. To determine the blood flow through the respective organs, a time constant (τ=-1/a) is determined from the relevant regression lines and the circulating blood volume may be divided by the time constant.
According to the present invention, the point of time at which MTT has lapsed is used as an effective time of injection at the site of measurement and this enables correct determination of the initial density and, hence, the circulating blood volume.
According to the present invention, the point of time at which the dye concentration peaks is used as an effective time of injection at the site of measurement and this enables positive determination of the initial dye density and, hence, the circulating blood volume.
According to the present invention, the point of time at which MTT has lapsed is used as an effective time of injection at the site of measurement and this enables correct determination of the initial dye density and, hence, the circulating blood volume. As a further advantage, the elimination of logarithmic transformational means contributes to simplify the overall configuration of the apparatus.
According to the present invention, the point of time at which the dye density peaks is used as an effective time of injection at the site of measurement and this enables positive determination of the initial dye density and, hence, the circulating blood volume. As a further advantage, the elimination of logarithmic transformational means contributes to simplify the overall configuration of the apparatus. | Using the principle of pulse oximetry, the relationship between the logarithm of dye density and the passage of time is obtained to determine a regression line for the linear portion of the relationship; an intial dye density in the blood is determined for the point of time that defines the mean transit time for the initial circulation of the injected dye on the regression line; and the circulating blood volume is calculated from the thus determined initial dye density. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is related to commonly assigned and co-pending U.S. application Ser. No. 351,413 filed May 12, 1989, the specification of which is incorporated by reference herein.
BACKGROUND OF THE INVENTION
The present invention relates generally to a punch press having a pair of upper and lower tool holders mounted to automatically bring respective punch and die sets to a work station for punching a variety of holes in sheet materials. More particularly, the invention relates to an apparatus for rotating a set of punches and dies in a tool holder at a single punching station in the press in a manner such that each punch and die is rotatable within the tool holder for punching a wider variety of holes with a reduced set of tools.
U.S. Pat. No. 4,658,688, assigned to the assignee of the present application, the specification of which is incorporated by reference herein. This patent discloses a turret punch press having upper and lower turret tool holders which carry a number of punch and die sets in individual tool holding stations in the turrets. At least one of the corresponding tool holding stations in the upper and lower turrets is indexable to different angular orientations. Rotation of the indexable punch tools is accomplished by a slidably mounted motor for engagement with a timing pulley, which, through a timing belt and harmonic gear drive, acts to rotate the tool holder which carries the punch and die set. In this device, each of the turrets may be equipped with tool stations which receive tool support devices that are rotatable to selectively position the tools at chosen angular positions by rotating the tool sets about their longitudinal axes.
U.S. Pat. No. 4,569,267 discloses a punch press which uses a punch tool assembly which contains at least two punch pins of different diameters or cross-sections. The punch pins are interchangeable in the working position by a control element which is slidable or rotatable about a pin support member. When the punch tool assembly is rotatable about the ram to effect the movement of the punch pins from operative to inoperative positions, a cooperating movable die is provided in order to ensure that the aligned die bores are cooperatively dimensioned and configured with respect to the punch pins. The punch tool assembly is held on the ram and moves with the ram and the pins, when not being used, are held in an elevated position while the operative pin is rigidly locked into a protruding position.
It has also been known to provide multiple tool holding members to be dropped into the individual rotatable stations, for example a station of the general type referred to in the aforementioned U.S. Pat. No. 4,658,688. Such devices are commercially available and are known as "multi-tools". When assembled in a indexable station, the drive mechanism to rotate the indexable station will be affected to rotate the multi-tool carrying member so as to present individual tools thereof into a ram-actuable position.
In this manner, particularly when using a turret punch press, the punch press may be equipped with a plurality of circumferentially spaced individual tool receiving openings which are aligned between the top and bottom turrets such that the top turret carries a punch tool and the bottom turret carries a complementary die tool, each of which can be indexed by rotation of the turrets to a position at the work station under the ram. Further, one or more of the individual stations of the turret may be provided with indexing mechanisms such that individual tools carried at those stations may be rotated about their axes to provide different angular orientations under the ram. In this manner, openings of the same shape but different angular orientation may be provided in the work piece with the same punch and die pair.
Further, a miniature turret or tool carrier carrying a plurality of individually circumferentially spaced tools may be received in one of the indexable stations in a turret such that indexing of the indexable station will rotate a selected one of the punch and die tools to the ram actuating work station.
While each of these devices provides a singular increase in productivity, they are, at least for the last two mentioned styles of device mutually exclusive. Thus, a single station of a turret may provide rotatability for a single tool about its axis, or a multi-tool may provide rotatability for a plurality of tools to present them one at a time at a fixed angular position.
SUMMARY OF THE INVENTION
This invention contemplates a punch assembly which may be provided at an indexable punching station in a punch press, wherein the punch assembly includes a striker body having a solid portion, and a punch carrier which carries a plurality of individual punches. A selectively actuable stop holds the striker body stationary, allowing the punch holder to be rotated so that a predetermined one of the plurality of punches will underlie the solid portion of the striker body. Afterwards, the entire punch assembly may be rotated to a variety of angular orientations. At any of these orientations, the ram may be actuated to cause the predetermined punch to extend downwardly below the punch assembly and through a sheet of material. Rotation of the assembly thus permits a single punch to be used to punch holes of the same shape but with differing angular orientations.
The die holder receives a plurality of corresponding dies having openings therein corresponding to the punches. The die holder is rotatable to maintain constant alignment between corresponding punches and dies.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an upper turret portion of a device according to the principles of the present invention.
FIG. 2 is a plan view of the device shown in FIG. 1 taken generally at line II--II.
FIG. 3 is a cross-sectional view of a punching tool assembly embodying the present invention.
FIG. 4 is a cross-sectional view of the device shown in FIG. 3, showing the punch assembly in a punching position.
FIG. 5 is an elevational view of the device shown in FIG. 3 along line V--V.
FIG. 6 is a cross-sectional view of the device shown in FIG. 3 along line VI--VI.
FIG. 7 is a broken-away detail of FIG. 5.
FIG. 8 is a schematic sectional view demonstrating the planar displacement incurred as a result of punch tool rotation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, the device of the present invention is shown generally at 10 and includes a punch press housing 12, an upper rotatable turret 14 and a lower rotatable turret 16, at least one indexable multi-tool holder 18 including a punch assembly 19 (FIG. 3), and a drive motor 20. More specifically, a ram 22 (FIGS. 3 and 4) is disposed in the punch press housing 12 for driving a punch P through a piece of sheet material M and into a die D. A plurality of punches P and dies D are mounted adjacent the perimeter of respective upper and lower turrets 14 and 16 which are rotatable to bring corresponding punches P and dies D under the ram 22. At least one indexable multi-tool holder 18 is mounted within the rotatable upper turret 14, and a corresponding indexable die 24 is mounted in the lower turret 22 so that the multi-tool holder 18 and die 24 ma be brought into registration under the ram 22.
The multi-tool holder 18 is provided with a geared bushing 26 that is rotatably driven by a gear box 28 which in turn is driven by timing belt 30 connecting a pair of pulleys 32 and 34. The servo motor 20 is mounted on the punch press housing 12 by a vertical slide 36 and is selectively engageable to the drive pulley 32. Vertical movement of the servo motor 20 with the slide 36 is provided by an actuator 38 (e.g. as a pneumatic actuator), connected between the slide 36 and the punch press housing 12. The servo motor 20 may be locked into its respective upper and lower positions by a slide lock mechanism 40. A resolver 41 provides feedback from the motor 20 to a programmed controller (not shown) to monitor the angular rotation of the motor 20.
The actuator 38 is connected at an upper end thereof to the punch press housing 12 by a bracket 42. The actuator 38 is connected to the slide 36 on which the motor 20 is mounted. The slide 36 slides vertically within slide rails 44,45 so that the motor 20 may be selectively engaged with the driver pulley 32.
FIG. 2 shows the upper turret 14 from above. The slide 36 is mounted between the V-shaped slide rails 44 and 45. The actuator 38 is seen suspended from the bracket 42 and the slide lock 40 can be seen more clearly. The timing belt 30 extends from the drive pulley 32 to the second pulley 34 under the housing 12. The gear drive 28 is enclosed by a housing 46 having a shaped opening 48 through which extends the geared bushing 26 of the indexable multi-tool holder 18. The turret 14 is rotatable about a turret axis 50 to bring other punch tools P under the ram 20.
As seen in FIG. 3 the indexable punch assembly 19 is provided with an annular lifter ring 52 extending therearound which is connected to lifter springs 54 extending from the turret 14 to the lifter ring 52. The ram 22 is shown above the punch assembly 19 and, during operation, will drive a predetermined punch P' through a piece of sheet material M and into the die 24. The lifter ring 52, in conjunction with the springs 54, then returns the punch assembly 19 to its original position lifting it from the sheet material M. A portion of the lower turret 16 is shown, and includes the indexable die assembly 24 which is rotated by an arrangement similar to that used to rotate the indexable punch assembly 19.
The punch assembly 19 is shown positioned below the ram 20 in a ready to work position. The punch assembly 19 includes a top striker cap 56 which is engaged by the ram 22 during punching. The cap 56 is secured to a striker body 58 by appropriate fasteners 59 such as threaded fasteners (see also FIG. 6). The striker body 58 is generally annular and, as seen in phantom in FIGS. 5 and 6, includes a solid portion in the form of a striker member 60 which selectively overlies a predetermined one of the punches P carried in the punch assembly 19. The striker member 60 extends axially downwardly from a main upper annular portion 61 of the striker body, thus leaving a relieved area 62 in the remaining circumferential area below the main upper body portion 61.
The top striker cap 56 is provided with at least one groove 57 which is selectively engaged by a pneumatically operated striker lock S to secure the striker cap 56 and the striker body 58 against rotation, as will be set forth in greater detail hereinbelow.
The punch assembly 19 includes a lifter sleeve member 63 that is normally supported on a stripper guide 64. The stripper guide 64 forms a lower outer portion of the indexable punch assembly 19 and includes vertical passages 66 for receiving a lower portion of the punches P. The stripper guide 64 also removably receives stripper buttons 68 as described in greater detail below. The stripper guide 64 is vertically reciprocally positioned within the geared bushing 26 and is keyed to the bushing 26 by an appropriate guide member such as a radially projecting pin 70 carried by the stripper guide 64 which is received in a vertical slot 72 in the bushing 26. Thus the stripper guide 64 will be free to move vertically relative to the bushing 26, however, will be prevented from rotating relative thereto.
The stripper guide 64 surrounds a punch carrier 74 and is selectively retained in predetermined rotational positions by appropriate detents, shown here as a plurality of radially inwardly projecting spring-loaded ball detent 75. Each ball detent 75, as shown in FIG. 7, includes a ball member 76 biased outwardly by a spring 77 and guided and retained by a threaded cylindrical member 78. The ball detents 75 are secured in threaded bores 79 through the stripper body 64. The ball members 58. The ball detents 75 and 79 grooves are positioned to correspond to the predetermined relative rotational positions of the striker body and the punch carrier. As shown in FIG. 5, two ball detents 75 may be provided on opposite sides of the punch assembly 19. Thus, the punch carrier 74 and the striker body 64 will be resiliently retained in one of a plurality of rotational positions relative thereto.
The punch carrier 74 has a plurality of vertically oriented passages 81 in which are received upper portions of the punches P. The punches P each have an enlarged head H which is received in an annular recessed area 82 formed at the top end of the punch carrier 74. A shoulder 84 is formed at the surface formed by the recessed area 82 which supports the head H of the punch P. The stripper guide 64 extends to an elevation above the head H of the punches P and a retaining ring 86 is snapped into a groove 88 in the stripper guide 64 to closely overlie the heads H of the punches.
Each of the punches P normally has a key K which is received in a vertical slot 90 in the punch carrier 74 to keep the punch angularly oriented within the punch carrier assembly 19. This is particularly required when the punch P does not have a circular working end W.
A center post 92 having a longitudinal axis 93 is used to hold the punch carrier 74 against the striker body 58. The center post 92 is positioned within a central vertical passage 94 in the striker body 58. The central vertical passage 94 includes an annular shoulder 96 which projects into tho passage 94 and the post 92 includes a post cap 98 which is removably secured to the post 92 by an appropriate fastener 100, shown here as a threaded fastener, such that the post will be prevented from moving downwardly relative to the striker body 58 once the cap 98 engages the shoulder 96.
The post 92 also has an annular shoulder 102 formed thereon which is positioned below the striker body shoulder 96, and which overlies the punch carrier 74. The punch carrier 74 is pressed against the post shoulder 102 by means of an appropriate resilient or elastic member 104, which may be in the form of a conical spring or Belleville washer. A bottom end of the post 92 is secured to the stripper guide 64 by an appropriate fastener 106, such as a threaded fastener. In this manner, the entire punch tool assembly 19 is held together.
In operation, the striker lock S is brought into engagement with one of the grooves 57 of the top striker cap 56, thus securing the striker cap 56 and the striker body 58 against rotation. The motor 20 is then actuated by the control system for the punch press, preferably a CNC control system (not shown), to act through the pulleys 32 and 34 to rotate the geared bushing 26. Rotation of the geared bushing 26 by the punch press control causes rotation of the portion of the punch assembly 19 about the axis 93 below the striker body 58, which thus places the striker body 58 and the punch carrier 74 in a predetermined relative position in which a selected punch P' is in a working position below the striker member 60, while disposing the other punches carried in the stripper guide 64 in an inactive position under the recess 62. Movable skid posts 108 are biased downwardly by resilient members, shown here as springs 110. The skid posts 108 and the retaining ring 86 prevent the inactive punches P from bouncing upwardly in the punch assembly 19 in response to vibrations of the punch press 10. In this manner, only one punch P' is moved to a working position while all of the other punches P are held in an inactive position.
After the predetermined punch P' has been moved to a position beneath the striker member 60 the striker lock S is retracted, thus permitting rotation of the entire punch assembly 19 to move the punch P' to a predetermined angular orientation. This capability is particularly significant when the punch P' does not have a circular working end W, since it permits a single punching tool to punch holes of the same shape, but with different angular orientations, through the sheet material M.
As mentioned previously, the die assembly 24 is rotated and maintained in alignment with the punch assembly 19 using an arrangement similar to that used to rotate the punch assembly 19.
During punching of the sheet material, the ram 20 descends and strikes the striker plate 56 causing the entire punch assembly 19 to move downwardly. The lifter ring 52 moves downwardly against the bias of the lifter springs 54. When the entire punch assembly has moved downwardly enough to cause the stripper buttons 68 to engage the sheet material M, as shown in phantom in FIG. 4, the punch carrier 74 moves downwardly relative to the stripper guide 64 thus compressing the resilient member 104. As this occurs, the striker body 58, through the striker member 60, continues to press against the predetermined punch P', resulting in the punch P' being extended beyond a bottom of the stripper button 68 and through the material M into a die D'. The remaining punches P which are not beneath the striker member 60 are retained by the skid posts 108 which are carried on the striker body 58 in the recessed area 62. The springs 110 are weaker than the resilient member 104 and therefore, once the other punches P engage the sheet material M, those other punches P will stop t heir downward movement relative to the material M. Only the ram 20, striker plate 56, striker body 58, and the individual punch P' under the striker member 60 will continue the downward movement to pierce through the material M.
When the ram 20 has terminated its downward stroke and begins to move upward, first the extended punch will move upwardly by action of the resilient member 104, then the entire punch assembly 19 will move upwardly by action of the lifter springs 54.
As can be seen in FIG. 8, when the predetermined punch P' is rotated to various positions about the axis 93 it will, of course, be displaced in a plane parallel to the material M. For example, in rotating from a position shown in solid line to that shown in broken line in FIG. 8, the punch P' will be displaced a distance D x along the X axis and Dr along the Y axis of a plane parallel to the sheet material M.
In a known fashion, the control system of the punch 10 continuously senses the rotational position of the punch assembly 19, and thus of the punch P'. The control system can thus be programmed very simply to calculate the extent and direction of the aforementioned displacement, and to accommodate the same by positioning the sheet M accordingly. The details of such accommodation will be easily ascertained by those skilled in the art of machine tool programming.
After a desired number of holes have been punched through the sheet material M with the punch P' in one position, the above process may be repeated in whole or in part. The motor 20 may be actuated to rotate the punch assembly 19 to a different orientation, thus permitting the punch P' to be used to punch holes having a different orientation, or the striker lock S may be actuated and the process repeated to select a different punch P.
Although the present invention has been described with reference to a specific embodiment, those of skill in the art will recognize that changes may be made thereto without departing from the scope and spirit of the invention as set forth in the appended claims. | A punch assembly which may be provided at a punching station in a turret punch press. The punch assembly includes a striker body having a solid portion, and a punch carrier which carries a plurality of individual punches. A selectively actuable stop holds the striker body stationary, allowing the punch holder to be rotated so that a predetermined one of the plurality of punches will underlie the solid portion of the striker body. Afterwards, the entire punch assembly may be rotated to a variety of angular orientations. At any of these orientations, the ram may be actuated to cause the punch to extend downwardly below the punch assembly and through a sheet of material. The rotation of the punch assembly to different orientations allows a single punch to be used to punch holes of the shape but with differing angular orientations. The die holder receives a plurality of corresponding dies having openings therein corresponding to the punches. The die holder is rotatable to maintain constant alignment between corresponding punches and dies. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to improving the efficiency of emissions control equipment, and more particularly to a use of auxiliary generator exhaust to provide heat required for emissions control processes.
A variety of activities produce exhaust having harmful levels of emissions (or pollution.) Large stationary emissions sources may have co-located emissions control systems. However, some emissions sources are mobile, and require similarly mobile emissions control systems. An example of a significant mobile emissions source is an ocean going vessel. A single container ship may produce as much emissions as 12,500 automobiles. U.S. patent application Ser. No. 10/835,197 for “Maritime Emissions Control System,” assigned to the assignee of the present invention, describes a mobile emissions control system which may be transported to a ship within a harbor, and which mobile emissions control system captures and processes a main exhaust flow from the ship to reduce emissions. The main exhaust flow may be from the ship's engine(s), auxiliary generators, or any other source of exhaust from the ship. The emissions control system of the '197 patent includes a bonnet which is lowered over the ship's stack, and a rather long duct for carrying the main exhaust flow from the ship's stack to emissions processing equipment carried by a barge alongside the ship. As a result of the distance the main exhaust flow must travel before reaching the emissions processing equipment, the temperature of the main exhaust flow is much lower that it's temperature upon being exhausted from an engine or engines. The '197 applications is herein incorporated by reference.
The emissions control system processing equipment described in the '197 patent includes a first system for reduction of nitrogen oxides (NOx) as its primary purpose. The first system comprises four stages. The first stage comprises a Pre Conditioning Chamber (PCC) quench vessel. The second stage comprises oxidation column. The third stage comprises reduction column. The fourth stage comprises a caustic (or polishing) column.
Although a preferred system for reducing NOx emissions is a Selective Catalytic Reducer (SCR) system, the first system does not include an SCR system because using known SCR systems would require the addition of substantial heat. The main exhaust flow would require heating to a high temperature before introduction into the SCR system. Also, ammonia used by SCR systems is preferably generated by heating urea. The cost and space required for an energy source for heating, made such known SCR systems impractical for a mobile emissions control system.
BRIEF SUMMARY OF THE INVENTION
The present invention addresses the above and other needs by providing an emissions control system utilizing otherwise wasted heat to efficiently reduce emissions in a main exhaust flow. Heat stored in exhaust from an auxiliary generator (i.e., auxiliary exhaust) may be used to convert urea solution ammonia used by a Selective Catalytic Reducer (SCR) system, and/or the auxiliary exhaust may be used to heat the main exhaust flow before entry into an SCR. Additionally, a heat exchanger may be used to transfer heat from a hot clean flow out of the SCR, to the main exhaust flow entering the SCR. Previously, mobile emissions control systems have not used SCR systems to reduce NOx because of the cost and space required for heater fuel. The efficient use of otherwise wasted heat reduces fuel cost and fuel storage requirements, and thereby makes an SCR systems feasible for use in mobile emissions control systems.
In accordance with one aspect of the invention, there is provided an emissions control system including an auxiliary generator and a reaction chamber for converting urea to ammonia. The exhaust from the auxiliary generator is ducted into the reaction chamber to provide heat for conversion of the urea to ammonia. A Selective Catalytic Reducer (SCR) system is used to processes a combination of a main exhaust flow from the stack of a ship and the ammonia. The emissions control system may further include a heat exchanger loop between the output and the input of the SCR for pre-heating the main exhaust flow. The heat exchanger loop preferably uses a liquid for conducting heat between the heat exchangers.
In accordance with another aspect of the present invention, there is provided a method for reducing the energy required to operate an SCR system. The method includes capturing hot exhaust gases of an auxiliary engine and mixing the hot exhaust gases with an atomized urea solution to convert the urea to ammonia. A main exhaust flow from the stack of a ship is collected for processing by the SCR system. The ammonia is mixed with main exhaust flow, and the resulting mixture is processed in an SCR to reduce NOx emissions. The method may further include capturing heat from the cleaned flow out of the SCR in a heat exchanger hot side, and releasing heat into the mixed flow at a heat exchanger cold side. The use of the hot exhaust gases from the auxiliary engine to convert the urea to ammonia, and the use of the heat exchanger to heat the mixture of ammonia and main exhaust flow, substantially reduces the cost of using the SCR system to reduce NOx emissions.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:
FIG. 1 is a maritime emissions control systems suitable for application of the efficient emissions control system of present invention.
FIG. 2 depicts a prior art Selective Catalytic Reducer (SCR) system.
FIG. 3 shows an SCR system utilizing wasted heat according to the present invention.
FIG. 4 is a method for processing an exhaust flow according to the present invention.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims.
The present invention provides a system and method for improving emissions control for engine exhaust, chemical process plants, or other pollution sources. The emissions control system and method according to the present invention provides more efficient operation of an emissions control system. The present invention is particularly useful where energy sources used to generate heat or power required for operation of the emission control system are not available or are inadequate, or where providing such sources of energy is not cost effective.
A maritime emissions control system for reducing emissions from a ship 10 is shown in FIG. 1 . A bonnet 14 is positioned over the ship stack 12 to collect a main exhaust flow. The main exhaust flow may be from the ship's engine(s), auxiliary generators, or any other source of exhaust from the ship. The main exhaust flow passes through a duct 16 to an emissions processing equipment 17 residing on a barge or smaller ship 18 . Such maritime emissions control system is described in U.S. patent application Ser. No. 10/835,197 for “Maritime Emissions Control System,” incorporated by reference above. Because of the long path from the sources, for example a ship engines or power generating equipment, the main exhaust flow is substantially cooled by the time the main exhaust flow reaches the emissions processing equipment 17 .
A preferred method of reducing the emissions in exhaust includes a Selective Catalytic Reduction (SCR) system. SCR systems generally use ammonia derived from urea to supplement the catalytic reaction—in essence, giving nitrogen oxides the “extra” molecules needed to convert to harmless nitrogen and water. Such systems have proven very useful and effective.
A prior art Selective Catalytic Reducer (SCR) system 19 for reducing NOx emissions is shown in FIG. 2 . The SCR system 19 comprises a urea source 20 for providing a flow of a urea solution 22 atomized and pumped by a compressor 34 into a reaction chamber 28 . A heat source 24 generates a heat flow 30 using energy 26 , which heat flow 30 is also provided to the reaction chamber 28 to heat the flow of urea solution 22 to generate ammonia. A resulting gaseous ammonia flow 32 passes into a mixing chamber 38 to mix with a main exhaust flow 36 . A mixed flow 40 is urged forward by a fan 42 to create an urged flow 44 to a heater 46 . The heater 46 heats the urged flow 44 to create a heated flow 48 into an SCR 50 . The heater 46 is preferably a duct burner, and preferably uses the same fuel as a generator within the SCR system 19 , and more preferably uses the same diesel fuel as a diesel generator within the SCR system 19 . The heater 46 also received the energy 26 . A chemical reaction in the SCR 50 between the ammonia and the NOx converts the NOx to nitrogen gas and water in a clean flow 52 .
The prior art SCR system 19 thus requires the following energy inputs in order to perform its function: energy 26 to produce the heat flow 30 to convert urea to ammonia, power to atomize and inject the urea solution into the reaction chamber 28 , power for the fan 42 to urge the mixed flow 40 through heater 46 and through the SCR 50 , energy 26 for the heater 46 to raise the temperature of the ammonia and main exhaust flow 36 mixture to the operating temperature of the SCR 50 .
In summary, the prior art SCR system 19 requires energy to generate heat at different steps of the process and the prior art SCR system 19 needs electrical energy for pumps and the like. This is very typical of many industrial and power generation processes to which the present invention applies. Because of these energy requirements, the prior art SCR system 19 shown in FIG. 2 requires too much energy to be practical with a mobile emissions control system such as the maritime emissions control system of FIG. 1 . In general, ammonia is derived from urea because urea is a much safer chemical than aqueous or anhydrous ammonia, and urea is easier to handle than ammonia.
An improved SCR system 53 according to the present invention is shown in FIG. 3 . An auxiliary engine 54 provides auxiliary exhaust 56 as a heat source for the reaction chamber 28 . The auxiliary engine 54 is preferably a diesel generator, a gas turbine generator, or a gasoline engine driven generator, and is more preferably a diesel generator, and provides power to the emissions control system. The auxiliary exhaust 56 both provides heat to convert the urea to ammonia, and remains mixed with the ammonia flow 32 to add heat to the mixed flow 40 . The urea is preferable in solution, and is more preferably an approximately 35 percent to approximately 40 percent urea aqueous solution. The urea flow 22 is pumped into the reaction chamber 28 by the compressor 23 , and preferably, the urea solution is atomized by compressed air from the air compressor 34 and sprayed into a flow of the hot auxiliary exhaust 56 . The auxiliary exhaust 56 is typically at a temperature of approximately 1000 degrees Fahrenheit and a temperature of approximately 650 degrees Fahrenheit is required to convert urea to ammonia. The ammonia mixed with the auxiliary exhaust 56 passes into mixing chamber 38 , where the ammonia mixes with the main exhaust flow 36 .
The mixed flow 40 b is urged forward by the fan 42 and through the heater 46 into the SCR 50 . The heater 46 is preferably a duct burner, and preferably uses the same fuel as a generator within the SCR system 52 , and more preferably uses the same diesel fuel as a diesel generator within the SCR system 52 . The heater 46 may alternatively receive power from a generator within the SCR system 52 . A chemical reaction in the SCR 50 between the ammonia and the NOx converts the NOx to nitrogen gas and water in the clean flow 52 . The auxiliary exhaust 56 may further be used to preheat the SCR 50 and the heat exchangers 58 , 60 before the main exhaust gas 36 is introduced into the improved SCR system 53 .
Continuing with FIG. 3 , the improved SCR system 52 may further include a heat exchanger for transferring heat normally exhausted from the SCR 50 , and using that heat to pre heat the mixed flow into the SCR 50 , thereby reducing the heating (and therefor energy) required by the heater 46 . A first mixed flow 40 a passes from the mixing chamber 38 to a heat exchanger cold side 58 , and a second mixed flow 40 b continues from the heat exchanger cold side 58 to the fan 42 . The cleaned flow 52 enters a heat exchanger hot side 60 where a fluid is heated, and the cleaned flow 52 exits the heat exchanger hot side 60 as a second cleaned flow 62 . The fluid flows through a rearward heat transfer tube 64 to the heat exchanger cold side 58 , where heat is transferred from the fluid to the mixed flow 40 a . The fluid then flows through a forward heat transfer tube 66 back to the heat exchanger hot side 60 . A second pump 34 b may reside in either the rearward heat transfer tube 64 or the forward heat transfer tube 66 to pump the fluid. The hot clean flow 52 is thus used to reduce the energy required by the heater 46 to heat the heated flow 48 to approximately 600 degrees Fahrenheit at entry to the SCR 50 . Rather than use the typical industrial process gas-to-gas heat exchanger, the present invention preferably uses a gas-to-liquid heat exchanger, thereby increasing the heat transfer efficiency. Preferably, a heat transfer oil or fluid is used.
Selective Catalytic Reducer systems are well know and available from: Argillon LLC, Alpharetta, Ga., Babcock Power Environmental, Worchester, Mass., CRI, Inc., Houston, Tex., Englehard Corp, Iselin, N.J., Haldor-Topsoe, Houston, Tex., Mitsubishi Power Systems, Newport Beach, Calif., and Johnson Matthey, San Diego, Calif.
A method for processing an exhaust flow according to the present invention is described in FIG. 4 . The method includes the steps of capturing hot exhaust gases of an auxiliary engine at step 80 , mixing the hot exhaust gases with urea at step 82 , converting the urea to ammonia at step 84 , Collecting a main exhaust flow from the stack of a ship at step 86 , Mixing the ammonia with main exhaust flow at step 88 , and Processing the mixture in a Selective Catalytic Reducer (SCR) system at step 90 . The method may further include capturing heat from the cleaned flow 52 out of the SCR 50 in a heat exchanger hot side, and releasing heat into a mixed flow 40 a at a heat exchanger cold side 58 .
The new and unique arrangements and processes of the present invention result in a significant reduction in the amount of energy that must be supplied for emission control system operation, and are capable of reducing the diesel fuel usage by a factor of two or three, depending on the temperature rise required for the incoming exhaust gas stream. In the particular example of FIG. 3 , the incoming gas temperature may be as low as 300 degrees Fahrenheit, while the SCR requires a minimum of 600 degrees Fahrenheit for operation. With an exhaust gas flow rate of 10,000 standard cubic feet per minute (SCFM), this invention reduces the energy required for heating the exhaust and the urea by more than a factor of three.
While a system including an SCR 50 was described above, the present invention is suitable for use with any mobile system having an auxiliary engine, and requiring heating of any flow within the system, or of an element of the system. The present invention is particularly suitable to any mobile emissions control system having an auxiliary engine and requiring a heating capability, and more particularly useful for any maritime emissions control system which must be mobile and self contained.
While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims. | An emissions control system utilizes otherwise wasted heat to efficiently reduce emissions in a main exhaust flow. Heat stored in exhaust from an auxiliary generator (i.e., auxiliary exhaust) may be used to convert urea to ammonia used by a Selective Catalytic Reducer (SCR) system, and/or the auxiliary exhaust may be used to heat the main exhaust flow before entry into an SCR. Additionally, a heat exchanger may be used to transfer heat from a hot clean flow out of the SCR, to the main exhaust flow entering the SCR. Previously, mobile emissions control systems have not used SCR systems to reduce NOx because of the cost and space required for heater fuel. The efficient use of otherwise wasted heat reduces fuel cost and fuel storage requirements, and thereby makes an SCR systems feasible for use in mobile emissions control systems. | 8 |
[0001] This application is a continuation-in-part of copending U.S. patent Ser. No. 10/938,202 filed on Sep. 10, 2004 and claims priority therefrom.
FIELD OF THE INVENTION
[0002] The present invention relates to the preparation of slurry catalyst compositions useful in the processing of heavy oils. These oils are characterized by low hydrogen to carbon ratios and high carbon residues, asphaltenes, nitrogen, sulfur and metal contents.
BACKGROUND OF THE INVENTION
[0003] Slurry catalyst compositions and means for their preparation are known in the refining arts. Some examples are discussed below.
[0004] U.S. Pat. No. 4,710,486 discloses a process for the preparation of a dispersed Group VIB metal sulfide hydrocarbon oil hydroprocessing catalyst. Process steps include reacting aqueous ammonia and a Group VIB metal compound, such as molybdenum oxide or tungsten oxide, to form a water soluble oxygen-containing compound such as ammonium molybdate or tungstate.
[0005] U.S. Pat. No. 4,970,190 discloses a process for the preparation of a dispersed Group VIB metal sulfide catalyst for use in hydrocarbon oil hydroprocessing. This catalyst is promoted with a Group VIII metal. Process steps include dissolving a Group VIB metal compound, such as molybdenum oxide or tungsten oxide, with ammonia to form a water soluble compound such as aqueous ammonium molybdate or ammonium tungstate.
[0006] U.S. Pat. No. 5,164,075 and U.S. Pat. No. 5,484,755, which are incorporated by references disclose processes for preparation of high activity slurry catalysts for hydroprocessing heavy hydrocarbon oils produced from Group VIB metal compounds. An aqueous mixture of the metal compound is sulfided with from greater than about 8 to about 14 standard cubic feet of hydrogen sulfide per pound of Group VIB metal. These patents demonstrate a process of forming a slurry catalyst precursor and adding it to a heavy feed oil to form the active catalyst.
[0007] These patents do not demonstrate the criticality of the oil viscosity in the formation of a highly active catalyst composition, nor the significance of using two distinctly different oils in forming such catalyst composition. In the inventions disclosed in these patents, the failure to form the oil and water emulsion or the slurry phase results in an inactive catalyst or a catalyst having low activity.
[0008] This invention discloses a new slurry catalyst composition that is highly active. This activity results from preparation of the catalyst using a process employing two hydrocarbon oils having appropriate viscosity ranges at 212° F. The first heavier oil is preferably a vacuum gas oil (VGO) and the second is preferably a light naphtha.
SUMMARY OF THE INVENTION
[0009] This invention is directed to a highly active catalyst composition which is suitable for processing heavy hydrocarbon oils. The catalyst is prepared by the following steps, resulting in a catalyst composition suitable for the hydroconversion of heavy oils, which is prepared by:
(a) mixing a molybdenum oxide and aqueous ammonia to form a molybdenum compound aqueous mixture; (b) sulfiding, in an initial reactor, the aqueous mixture of step (a) with a gas comprising hydrogen sulfide to a dosage greater than 8 SCF of hydrogen sulfide per pound of molybdenum metal to form a slurry; (c) promoting the slurry with a Group VIII metal compound; (d) mixing the slurry of step (c) with a first hydrocarbon oil having a viscosity of at least 2 cSt (or 32.8 SSU) @ 212° F. to form Mixture X; (e) combining Mixture X with hydrogen gas and a second hydrocarbon oil in a second reaction zone, the second hydrocarbon oil having a boiling point in the range from 50° F. to 300° F. and having a lower viscosity than the first hydrocarbon oil; thereby forming an active catalyst composition admixed with a liquid hydrocarbon; and (f) recovering the active catalyst composition by separation from the gaseous hydrocarbon of step (e).
[0016] This new highly active slurry catalyst composition may be stored in an active and concentrated state. The catalyst composition can be directly introduced into any of the known heavy oil or residuum upgrading processes under the existing conditions of that process, The catalyst can upgrade the very high viscosity carbonaceous and/or highly paraffinic feedstocks with or without dilution of the feedstock.
BRIEF DESCRIPTION OF THE DRAWING
[0017] The FIGURE illustrates the steps involved in the preparation of the catalyst composition
DETAILED DESCRIPTION OF THE INVENTION
[0018] This invention relates to a new highly active slurry catalyst composition formed from the addition of a first hydrocarbon oil having a viscosity of at least 2 cSt (or 32.8 SSU) @ 212° F., and a second hydrocarbon oil having a boiling point in the range from 50° F. to 300° F. The preferred viscosity range for the first hydrocarbon oil is from at least about 2 cSt (or 32.8 SSU) @ 212° F. to 15 cSt (or 77.9 SSU) @ 212° F.
[0019] The FIGURE illustrates the steps involved din the process of this invention. The active slurry catalyst composition is prepared by mixing line 5 , containing an oxide of molybdenum, and line 7 , containing aqueous ammonia, in a mixing zone 10 . The temperature of the mixing zone is generally in the range from about 80° F. to about 200° F., preferably from about 100° F. to about 150° F., and most preferably from about 110° F. to about 120° F., The pressure of the mixing zone 10 is generally from about atmospheric pressure to about 100 psig, preferably from about 5 psig to about 35 psig, and most preferably from about 10 psig to about 20 psig. The molybdenum oxide is dissolved in water containing the ammonia. The amount of ammonia added is based on the ratio of NH 3 to molybdenum oxide in lbs/lbs and generally ranges from 0.1 lbs/lbs to about 1.0 lbs/lbs, preferably from about 0.15 lbs/lbs to about 0.50 lbs/lbs, and most preferably from about 0.2 lbs/lbs to about 0.30 lbs/lbs. The dissolved molybdenum oxide in aqueous ammonia is moved via line 15 to the first reaction zone.
[0020] The amount of hydrogen sulfide (line 9 ) added to the reaction zone 20 is based on the ratio of H 2 S to molybdenum oxide in SCF/lbs and generally ranges from 4.0 SCF/lbs to about 20 SCF/lbs, preferably from about 8.0 SCF/lbs to about 15 SCF/lbs, and most preferably from about 12 to 14 SCF/lbs. The reaction time in the first reaction zone ranges from about 1 hour to 10 hours, preferably from 3 hours to 8 hours, and most preferably from about 4 hours to 6 hours, Conditions include a temperature in the range from 80° F. to 200° F., preferably in the range from 100° F. to 180° F., and most preferably in the range from 130° F. to 160° F. Pressure is in the range from 100 to 3000 psig, preferably in the range from 200 to 1000 psig, and most preferably from 300 to 500 psig. The resultant aqueous slurry is the catalyst precursor.
[0021] The aqueous, slurry is combined with a Group VIII metal compound such as Ni or Co, as disclosed in U.S. Pat. No. 5,484,755. As an enhancement of the denitrogenation activity of the active slurry catalyst of the present invention, it is preferred that a Group VIII metal compound be added to the slurry before mixing the slurry with feed oil and a hydrogen containing gas at elevated temperature and pressure. Such Group VIII metals are exemplified by nickel and cobalt. It is preferred that the weight ratio of nickel or cobalt to molybdenum range from about 1:100 to about 1:2. It is most preferred that the weight ratio of nickel to molybdenum range from about 1:25 to 1:10, i.e., promoter/molybdenum of 4-10 weight percent. The Group VIII metal, exemplified by nickel, is normally added in the form of the sulfate, and preferably added to the slurry after sulfiding at a pH of about 10 or below and preferably at a pH of about 8 or below. Group VIII metal nitrates, carbonates or other compounds may also be used. In view of the high activity of the slurry catalyst of the present invention, the further promotion by Group VIII metal compounds is very advantageous.
[0022] The aqueous slurry is moved, via line 25 , to mixing zone 30 . Mixing zone 30 employs an inert atmosphere which can comprise nitrogen, refinery gas, or any other gas having little or no oxygen. The aqueous slurry and a first hydrocarbon oil (line 11 ), such as VGO, are mixed continuously in a high shear mode to maintain a homogeneous slurry in mixer 30 . High shear mixing is defined as intense mixing wherein solids are suspended completely off the vessel bottom and slurry is supplied to at least one-third of the fluid batch height and is suitable for slurry draw off at low exit nozzle elevations. High shear mixing encompasses a range from 100 to 1600 RPM. Preferably the mixing rate is greater than 500 RPM and most preferably greater than 1500 RPM.
[0023] The first hydrocarbon oil has a kinetic viscosity of at least 2 cSt (or 32.8 SSU) @ 212° F. The kinetic viscosity can generally range from about 2 cSt (or 32.8 SSU) @ 212° F. to about 15 cSt (77.9 SSU) @ 212° F., preferably from about 4 cSt (39.5 SSU) @ 212° F. to about 10 cSt (59.2 SSU) @ 212° F., and most preferably from about 5 cSt (42.7 SSU) @ 212° F. to about 8 cSt (52.4 SSU) @ 212° F. The first hydrocarbon oil causes the initial transformation of the catalyst precursor to an oil base from a water base. The ratio of molybdenum oxide to oil is at least less than 1.0, preferably less than 0.5, and more preferably less than 0.1. If the kinetic viscosity of the oil is below about 2 cSt (or 32.8 SSU) @ 212° F. or above about 15 cSt (77.9 SSU) @ 212° F., the first transformation of the catalyst precursor will result in catalyst particles agglomerating or otherwise not mixing.
[0024] The material from mixing zone 30 moves to reaction zone 40 via line 35 . Prior to entering reaction zone 40 , the material may be combined with makeup oil of the viscosity range of the first hydrocarbon oil. Hydrogen is also added to the mixture before it enters reaction zone 40 .
[0025] In reaction zone 40 , a second, lighter hydrocarbon oil is added to the material from mixing zone 30 . The second oil, preferably a light naphtha, preferably possesses a kinetic viscosity of less than 0.3 cSt at 212° F. One source of this second oil may be recycle material from the high pressure separator 50 (line 45 ). High shear mixing is also employed in the reaction zone 40 in order to maintain a homogenous slurry.
[0026] The second hydrocarbon oil has a boiling point generally in the range from about 50° F. to about 300° F., preferably from about 75° F. to about 250° F., and most preferably from about 100° F. to about 150° F. The ratio of the volume of the second oil to the first oil is greater than 1, preferably greater than 5, and most preferably greater than 10. The temperature of the reaction zone 40 generally ranges from about 300° F. to 700° F., preferably from about 350° F. to about 600° F., and most preferably from about 350° F. to about 500° F. The pressure of the reaction zone 40 generally ranges from about 1000 psig to about 3500 psig, preferably from about 1500 psig to about 3000 psig, and most preferably from about 2000 psig to about 3000 psig. The hydrogen flow to the reaction zone 40 generally ranges from about 500 SCFB to about 10,000 SCFB, preferably from about 1000 SCFB to about 8000 SCFB, and most preferably from about 3000 SCFB to about 6000 SCFB. The reaction time in the reaction zone 40 ranges from about 11 minutes to 5 hours, preferably from 30 minutes to 3 hours, and most preferably from about 1 hour to 1.5 hours. The resultant slurry mixture is the active catalyst composition in a mixture of the first hydrocarbon oil and the second hydrocarbon oil. The slurry mixture is passed, through line 55 , to high pressure separator 50 . The high pressure separator operates in a range from 300° F. to 700° F. The second hydrocarbon oil is removed overhead through line 45 and recirculated back to the third reaction zone 40 . The active catalyst composition is moved through line 65 to storage tank 60 . The active catalyst composition is continuously mixed in storage tank 60 to maintain a homogenous slurry in a hydrogen atmosphere with little or no oxygen. In this way, the catalyst activity and stability are maintained.
[0027] The catalyst composition is useful for upgrading carbonaceous feedstocks which include atmospheric gas oils, vacuum gas oils, deasphalted oils, olefins, oils derived from tar sands or bitumen, oils derived from coal, heavy crude oils, synthetic oils from Fischer-Tropsch processes, and oils derived from recycled oil wastes and polymers. The catalyst composition is useful for but not limited to hydrogenation upgrading processes such as thermal hydrocracking, hydrotreating, hydrodesulphurization, hydrodenitrification, and hydrodemetallization.
EXAMPLE
Catalyst Preparation (with Light Oil)
[0028] 540 gram MoO 3 is mixed with 79 grams of NH 3 and 2381 grams of H 2 O to form a solution of total 3000 grams. The solution is then reacted with 10.71 SCF of H 2 S by passing a gas mixture of 20% H 2 S in H 2 into the solution under strong mixing. The reactor temperature is 150° F. and the total pressure is 400 psig, and the reaction time is 4 hours. After reaction, 460 grams NiSO 4 solution which contains 36 grams of Ni is added to the above obtained slurry. The obtained slurry mixture is then mixed with 3500 grams of vacuum gas oil (first hydrocarbon oil) at 100° F. The viscosity of the VGO is 5 cSt @ 212° F. The resulting mixture is then pumped into a continuously flow stirred tanked reactor (perfectly mixed flow reactor) and mixed with heptane and H 2 , the ratio of heptane/VGO is 9.1 and H 2 gas rate is 5000 SOC/B. Heptane is the second hydrocarbon oil. The reactor pressure is 2500 psig and reactor temperature is 400° F., the total reaction time is 1 hour. The reaction products go to a hot high pressure separator with temperature 500° F. (HPS is also at 2500 psig) to separate gas and liquid slurry. The obtained liquid slurry contains the highly active catalyst component. | The instant invention is directed to the preparation of a catalyst composition suitable for the hydroconversion of heavy oils. The catalyst composition is prepared by a series of steps, involving mixing a Group VIB metal oxide particularly molybdenum oxide and aqueous ammonia to form an aqueous mixture, and sulfiding the mixture to form a slurry. The slurry is then promoted with a Group VIII metal. Subsequent steps involve mixing the slurry with a hydrocarbon oil and combining the resulting mixture with hydrogen gas and a second hydrocarbon oil having a lower viscosity than the first oil. An active catalyst composition is thereby formed. | 2 |
FIELD OF INVENTION
[0001] This invention relates to high temperature seals for hydraulic assemblies and in particular seals which are suitable for hydraulic fasteners and nuts.
BACKGROUND OF THE INVENTION
[0002] Hydraulically tensioned nuts, washers and similar fasteners provide a means by which a stud or bolt can be tensioned by hydraulically actuating the nut or washer to exert a tensile force on the stud or bolt. These nuts and washers often operate under extreme pressure and temperature.
[0003] Hydraulic nuts or similar fasteners are typically pretensioned mechanically and thereafter hydraulic pressure is applied to a chamber within the fastened structure to generate an hydraulic force which applies an axial tensile load to a stud or nut engaged by the fastener. A locking collar may be provided to retain the tension after relieving the chamber of pressure.
[0004] Seals for use with hydraulic pressure devices are typically made of elastomeric material such as nitrile rubber or polyurethane. The ways in which these seal against the passage of fluid pressure can be divided into two types referred to herein as primary and secondary mechanisms. The primary mechanism of sealing acts during the initial application of fluid pressure. As this pressure increases, the elastomeric seal is deformed and forced into a position where the seal bridges the gap to be sealed, hereinafter referred to as the “extrusion gap”, in order to establish a secondary seal.
[0005] It is typical of hydraulically activated piston/cylinder arrangements that as the operating pressure increases, the cylinder walls expand radially causing a proportional increase in the extrusion gap between piston and cylinder. A limiting factor in the operation of hydraulic nuts is the effectiveness of their seals. Factors such as high pressures, high temperatures, service life under adverse conditions, limit their field of application and effectiveness. If these factors become extreme, either singularly or in combination, the materials which are commonly used as sealing agents fail. Failure occurs when there is flow or movement of the seal material into the extrusion gap under pressure and /or temperature and sealing is lost.
[0006] In extreme temperature/pressure applications, such as in electricity generators and nuclear power plant reactors, it is critical that seals do not fail as loss of tension applied to the studs or bolts for example in a generator housing or at a pipe flange joint, as such failure could result in a catastrophic disaster. U.S. Pat. No. 6,494,465 (Bucknell) (=International Application PCT/AU97/00425 =International Publication WO 98/00660) discloses a range of hydraulic seals for hydraulic assemblies capable of operating at high temperatures. The seals incorporate lips which provide low pressure sealing between for example, a piston and a cylinder, and which are configured to move across the gap to be sealed at higher pressures with a base angled on a slope or a cup shape nestled into a groove. The seals may be formed of elastomeric material and/or thin sheet metal.
[0007] The seals of U.S. Pat. No. 6,494,466 have been used in many successful installations of high temperature, hydraulically tensioned fasteners in the electricity generation and nuclear power industries. However, experience has shown that there is a need for different types of sealing arrangements for fasteners, especially in response to specific operational requirements.
OBJECT OF THE INVENTION
[0008] It is therefore an object of the present invention to provide high temperature seals for hydraulic assemblies such as fasteners which have improved sealing characteristics able to tolerate extreme factors such as high pressures and for high temperatures. It is a further object of the invention to provide seals which achieve a greater extended service life under such adverse conditions or at least provide an alternative to prior art seals.
STATEMENT OF THE INVENTION
[0009] According to the present invention, a sealing device for an hydraulic assembly wherein hydraulic fluid is contained in a working chamber formed between the body and the thrust member of the assembly comprises an annular seal with opposed sealing faces which are urged into sealing engagement between the body and the thrust member which have convergent sealing faces.
[0010] Preferably the device also comprises an annular mating spring clip retained in the body or in the thrust member of the assembly which bears against a non-sealing face of the annular seal to ensure primary sealing engagement between the body and the thrust member.
[0011] Preferably the annular seal is formed with a pair of annular sealing lips which are urged into sealing engagement between the body and the thrust member of the assembly at an initial low pressure, the remainder of the seal being urged into sealing engagement at higher pressures.
[0012] Preferably the seal is elastically deformed when it is placed in position so that it springs towards its original shape thus urging sealing engagement between the body and the thrust member.
[0013] Preferably the seal has a rounded heal which rolls under pressure to maintain sealing engagement.
[0014] In an alternative form the sealing device is provided with a pressure relief valve tapped into the over-stroke end of the chamber to protect the annular seal from over-stroke damage comprising a porous body which allows hydraulic fluid to bleed from the chamber and which allows the annular seal to pass the tapping point without obstruction.
[0015] Preferably the porous body is formed from sintered metal or porous ceramics.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] To enable the invention to be fully understood, preferred embodiments will now be described with reference to the accompanying drawings, in which:
[0017] FIG. 1 is a sectioned view of the components of an hydraulically assisted nut;
[0018] FIG. 2 is a sectioned view of the assembled hydraulic nut assembly of FIG. 1 ;
[0019] FIGS. 2A and 2B are cross sections of prior art seals;
[0020] FIGS. 2C to 2Q are cross sections of seals in accordance with the present invention;
[0021] FIG. 3 is a sectioned view of an hydraulic nut in the full reset position' fitted with the pressure relief device of the present Invention;
[0022] FIG. 4 is a sectioned view showing the nut of FIG. 3 in the over-straight condition;
[0023] FIG. 5 is an enlarged view of part of the nut of FIG. 4 ;
[0024] FIGS. 6 and 7 are cross sections of distorted prior art seal lips; and
[0025] FIGS. 8 and 9 are cross sections of seals of FIGS. 2F to 2Q .
DETAILED DESCRIPTION OF THE INVENTION
[0026] FIGS. 1 and 2 illustrate the components and assembly respectively of the prior art hydraulically assisted nut disclosed in U.S. Pat. No. 6,494,565, including a piston 51 , cylinder 52 , locking ring 59 , thrust washer 50 and a hydraulic working chamber 53 .
[0027] Seals 63 , 64 are provided in closed working chamber 53 between piston 51 and cylinder 52 in the manner described in U.S. Pat. No. 6 , 494 , 565 .
[0028] FIGS. 2A and 2B illustrate the generally V shaped prior art seals 63 , 64 . FIG. 2C shows an interference seal 10 in accordance with the present invention, which is responsive to a slow injection of an hydraulic medium of low viscosity. It offers greater mobility than prior art seals 63 , 64 as it has a greater angle as seal 10 is driven by pressure. There is a slight difference in angle between face 11 of seal 10 and face 71 of piston 51 which ensures that the thicker part of body 12 of seal 10 is driven against face 71 of piston 51 and cylinder 52 . This seal construction is effective in applications not requiring a slow pressure charging routine.
[0029] FIG. 2D illustrates a similar construction where spring clip 81 on cylinder 52 ensures that primary sealing contact is made with the sealing faces. FIG. 2F is like the prior art designs of FIGS. 2A and 2B and has thin seal lips 113 , 114 to receive an initial lower pressure and therefore produces two phases of sealing. FIG. 2H shows seal 210 with seal lips 213 , 214 , which operate on the same principles but which can be pressed from sheet metal.
[0030] Seals 110 , 210 and 310 of FIGS. 2F , 2 H and 2 G, respectively are formed in shapes which ensure that a spring force is applied to the seal lips 113 , 114 , 213 , 214 , 313 , 314 to provide primary sealing when seals 110 , 210 and 310 are inserted in the working position. The secondary sealing action is activated by increasing the charge pressure. Seal 310 of FIG. 20 combines initial low pressure sealing of lips 311 , 314 with a double ramp to force backup ring 320 to do most of the sealing work. In this arrangement, the seal function becomes more like that of a “V-packing” where multiple lips share the work.
[0031] FIG. 2E illustrates seal 410 in which lip 413 in contact with the wall of piston 510 does virtually all the work of sealing. Seal 410 is made larger than the limiting dimensions of the seal groove and piston wall so that when it is fitted, it has a residual spring force to drive it against the wall. The lip 413 of seal 410 is allowed to flex and follow the expansion of cylinder 52 caused by the increasing charge pressure. Seal 410 is best used with relatively low pressures and minimum radial wall deflection.
[0032] The seals shown in FIGS. 2J to 24 are of a quite different construction in that they are spring loaded on installation so that primary sealing is effected by the seal's attempt to return to its original shape. This is illustrated in FIGS. 8 and 9 where the seal which is made in the shape shown in FIG. 8 is inserted into position shown in FIG. 9 so that it is forced inwards by the seal groove, and will therefore be forced against the adjacent outer cylinder walls.
[0033] The primary forces are selected to suit the conditions and the seals are made from material of the required elasticity so that they deform when inserted to the shape required. The seals shown in FIGS. 2J to 2Q all use this spring loading principle to achieve primary sealing. This sealing action is then reinforced by the increasing internal pressure in cylinder 52 . The sealing force exerted against the wall is determined by the area of the seal which responds proportionately to the injected pressure.
[0034] Deformation of thin sections of seal elements under the effects of pressure and temperature decreases and often destroys the seal's integrity. Prior art seals with thin lips as shown in FIGS. 2A and 2B are required to maintain some spring pressure against the cylinder walls at all times. This means that a material of sufficient yield strength is selected so that the seal does not deform plastically in regions of high local stress. If the material strength is not sufficient permanent deformation can occur. This tends to happen progressively from thinner section to a point where there is sufficient thickness to balance the destructive force, so that when the seal lip is deformed in this manner, it can curl back from contact with the cylinder wall.
[0035] Increasing temperatures lower the effective strength of most materials and particularly that of engineering steels and a metal seal which is deformed in use will be difficult to return to service. Medium under pressure forces into the gap created at the thin edge and acts as a wedge to force the lower sections away from sealed contact with the cylinder walls. This problem with known seals is illustrated in FIGS. 6 and 7 .
[0036] The innovative design of the “seal ring” seals of FIGS. 2J to 2Q solves this problem by the action of the charging fluid's pressure upon the opposed surface of the seal, which generates thrust forces to aid sealing on the critical faces. Such force is directly related to incremental pressure, and therefore, maintains the relationship required for sealing throughout the range. The problem of heat affecting thin sections and causing permanent deformations is resolved by the new designs having thick sectional areas.
[0037] Seals 510 , 610 and 710 exhibiting these characteristics are illustrated in FIGS. 2J , 2 K and 2 N. Seals 810 and 910 illustrated in FIGS. 2L and 2M show hollow versions of the seals 510 and 610 of FIGS. 2J and 2K , but generally would have limited application in practice. Seals 910 , 1010 of FIGS. 2O and 2Q show how the principles of the “spring ring” can be applied to thinner sections of materials.
[0038] These can be made inexpensively and are generally sufficient for hydraulically assisted nut fasteners used at lower operating pressures. Seal 110 or FIG. 2P illustrates a version of the seal which can be made in a chevron form wherein the pressure will act to expand the seal's outer diameter and provide sealing against the wall of cylinder 52 .
[0039] It will be readily apparent to the skilled addressee that the selection of the material for the seals, the particular shape, size and configuration of the seals, will be dependent on the intended applications. Factors which will be significant in selecting the appropriate seal will include the operating temperatures and pressures of the hydraulic assemblies and the type and pressure of the charging medium.
[0040] A further factor which destroys seal integrity is overstroke, that is, during attempted operation, the seal travels beyond its practical working limit, resulting in failure and a dangerous burst release of high pressure fluid. To prevent such failure, it is desirable to introduce a bleed-off port into the construction of the hydraulically assisted fastener nut. Should the seal be forced to travel over its stroke limit, then this port minimises seal damage by allowing fluid to escape. However, the seal would be irreparably damaged even by its partial transit across the port since extreme internal pressures extrude the seal material as it passes, even scratching hardened steel surfaces.
[0041] FIGS. 3 to 6 illustrate a bleed port 100 which accommodates a pressure relief device comprising a porous plug 101 . The inner face 102 of the plug 101 is profiled to conform to the adjacent sealing wall face 52 A so that seal 63 is not damaged as it moves over bleed port 100 . The material of the porous plus 101 is chosen to have high strength to provide support to seal 63 as it moves over bleed port 100 , and is porous to allow fluid 103 to migrate from pressure chamber 53 freely. As seal 63 moves across bleed port 100 , more material of porous plug 101 is exposed and the bled rate is increased. The density and relative porosity of plug 101 is chosen to provide appropriate strength and bleed rate for the application. Low cost materials of choice for plug 101 are sintered metal and porous ceramics but other materials may be suitable.
[0042] It will be readily apparent to the skilled addressee that porous plug 101 of the pressure relief device will protect seal 63 against damage if it moves from the full reset position shown in FIG. 3 to the overstroke condition shown in FIG. 4 . The porous bleed plug of the present invention can be applied to any hydraulic assembly where overstroke damage can occur to seals.
VARIATIONS
[0043] It will be realized that the foregoing has been given by way of illustrative example only and that all other modifications and variations as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth. Throughout the description and claims to this specification the word “comprise” and variation of that word such as “comprises” and “comprising” are not intended to exclude other additives components integers or steps. | A sealing device for a hydraulic assembly wherein hydraulic fluid is contained in working chamber ( 53 ) formed between body ( 52 ) and thrust member ( 51 ) of the assembly. The device comprises annular seal ( 63 ) with opposed sealing faces which are urged into sealing engagement between body ( 52 ) and thrust member ( 51 ) which have convergent sealing faces. The device may also have a pressure relief valve ( 100 ) tapped into the over-stroke end of chamber ( 53 ) to protect seal ( 63 ) from over-stroke damage comprising porous body ( 101 ) which allows fluid to bleed from chamber ( 53 ) and allows seal ( 63 ) to pass the tapping point without obstruction. | 8 |
TECHNICAL FIELD
[0001] The present invention relates to a process which makes it possible to improve the adhesion of carbon fibres with regard to an organic matrix forming, with these fibres, a composite material and resulting from the chain polymerization of a curable resin.
[0002] This process, which makes it possible to obtain composite materials with noteworthy properties of resistance to stresses, both transverse (that is to say, perpendicular to the direction of the carbon fibres) and longitudinal (that is to say, in the direction of the carbon fibres), is very particularly advantageous in the aeronautical, aerospatial, railway, ship building and automobile industries, whether in the production of structural components, engine components, passenger compartment components or bodywork components.
[0003] However, it can also be used in other types of industry, such as the armaments industry, for example in the production of components participating in the construction of missiles or of missile launch tubes, or that of sports and leisure articles, for example in the production of articles intended for water sports and for sports which involve sliding.
STATE OF THE PRIOR ART
[0004] Composite materials are heterogeneous materials which make it possible to make use of the exceptional mechanical properties of materials, the manufacture of which is only known in the form of fibres (and not in bulk form), by embedding them in a matrix formed of a cured organic polymer (or resin), which makes it possible to bond the fibres to one another, to distribute the stresses in the composite material and to protect the fibres against chemical attacks.
[0005] A necessary condition for the production of a high performance composite material is that the bonding between the fibres and the matrix of which it is composed is good. This is because, if the fibres/matrix bonding is inadequate, then a composite material is obtained with mediocre transverse mechanical properties (such as resistance to shearing) and thus with very limited possibilities of use, components made of composite materials generally being intended to operate under a state of three-directional stress.
[0006] Carbon is chemically rather unreactive and naturally exhibits a low adhesion with regard to polymer matrices. Consequently, manufacturers of carbon fibres have straightaway sought to adapt their fibres to the resins intended to be used as matrices by manufacturers of components made of composite materials.
[0007] Thus it is that the following have been proposed:
[0008] 1) surface treatments which are all targeted at creating, at the surface of the fibres, functional groups capable of reacting with chemical functional groups carried by the resins; they are mainly electrolytic or chemical oxidation treatments (see, for example, JP-A-3076869 [1]) but other types of treatment have also been described, such as plasma heat treatments (see, for example, EP-A-1 484 435 [2]), electrolysis in an acidic or basic medium (EP-A-0 640 702 [3]) or the implantation of atoms of Si or B type (JP-B-2002327374 [4]);
[0009] 2) the use of specific sizing agents, that is to say by the deposition, on the surface of the fibres, of products having the role of enhancing the compatibility of the fibres with regard to the resins, of facilitating their impregnation by the resins and of providing “attaching” between the fibres and the matrices formed by the polymerization of these resins; generally, the sizing agents used are polymers or copolymers with complex chemical structures, the choice of which is mainly guided by experience; and
[0010] 3) the grafting to the surface of the fibres of an elastomeric phase (Wu et al., Carbon, 34, 59-67, 1996 [5]) or of polymers of polyester, vinyl polymer (in particular polystyrene) or polyacetal type (Tsubokawa, Carbon, 31, 1257-1263, 1993 [6]) capable, here again, of enhancing the compatibility of the fibres with regard to the resins.
[0011] It should be noted that sizing agents are also used on the carbon fibres for other objectives than that of improving the bonding thereof with an organic matrix, such as, for example, that of facilitating the handling thereof.
[0012] While the treatments mentioned above are generally relatively effective in the case of matrices obtained by thermal polymerization of resins (that is to say polymerization induced by heat), it turns out that they are not effective or insufficiently effective when the matrices are produced with resins, the polymerization of which is brought about by light radiation (visible or ultraviolet light) or ionizing radiation (β or γ radiation or X-rays).
[0013] This is because experience shows that the composites obtained with resins polymerized under radiation exhibit transverse mechanical performances which are markedly inferior to those of the better composites produced with resins polymerized by the thermal route, which is conventionally interpreted as the fact that the fibres/matrix bonding remains inadequate despite the treatments applied to the carbon fibres by the manufacturers thereof.
[0014] In point of fact, the polymerization of resins under radiation moreover exhibits a number of advantages with respect to the polymerization of resins by the thermal route, these advantages being related in particular to the possibility of operating without autoclaves and thus of more easily manufacturing composite components which are large in size or complex in structure and of obtaining much higher polymerization rates, which makes possible higher production rates for lower costs.
[0015] The Inventors thus set themselves the objective of providing a process which makes it possible to improve the adhesion of carbon fibres with regard to a polymer matrix in the case where this matrix is obtained by polymerization under radiation of a curable resin and more specifically of a resin which can be cured by chain polymerization since, in practice, the resins capable of polymerizing under radiation are resins, the polymerization of which takes place by a chain mechanism.
[0016] Furthermore, they set themselves the objective that this process be applicable to the greatest possible number of types of carbon fibres capable of being used in the manufacture of composite materials (long fibres, medium-length fibres, short fibres, oxidized fibres, sized fibres, and the like).
[0017] In addition, they set themselves the objective that the operating costs for this process be compatible with the use thereof on the industrial scale.
DESCRIPTION OF THE INVENTION
[0018] These objectives and yet others are achieved by the present invention, which provides a process for improving the adhesion of carbon fibres with regard to an organic matrix forming a composite material with these fibres, this composite material being obtained by bringing the fibres into contact with a resin which can be cured by chain polymerization and then polymerizing the resin, which process is characterized in that it comprises the grafting, to the surface of the fibres, before they are brought into contact with the resin, of groups capable of acting as chain transfer agents during the polymerization of said resin.
[0019] The carbon fibres as obtained by conventional processes for the pyrolysis of polyacrylonitrile (PAN), rayon, viscose, pitch and other oil residues are each composed of a multitude of monofilaments which can be more or less bonded to one another according to the treatments to which these fibres were subjected during the manufacture thereof.
[0020] For this reason, in that which precedes and in that which follows, the term “surface of the fibres” is understood to mean both the surface of the monofilaments themselves and the surface of assemblages resulting from the bonding of a plurality of monofilaments to one another. In the same way, the term “surface of a fibre” is understood to mean both the surface of a monofilament and that of an assemblage resulting from the bonding of several monofilaments to one another.
[0021] Furthermore, in that which precedes and in that which follows, the term “polymerization” should be understood as comprising not only the formation of polymer chains by bonding of monomers or prepolymers to one another but also the formation of a three-dimensional network by the establishment of bonds between these polymer chains, which is commonly known as crosslinking.
[0022] Thus, according to the invention, it is by grafting, to the surface of the carbon fibres, before the latter participate in the process for the manufacture of the composite material, organic groups capable of subsequently acting as chain transfer agents during the polymerization of the resin intended to form the organic matrix of the composite material that the adhesion of these fibres with regard to this matrix is enhanced.
[0023] In the current state of their studies, the Inventors believe that this increase in adhesion would be related to the fact that the groups thus grafted to the surface of the fibres will be converted, during the polymerization of the resin, to active centres (that is to say to radicals or to ions, depending upon whether the chain polymerization is of radical type or of ionic type) by reaction with growing polymer chains and that these active centres will be capable of initiating the formation of new polymer chains starting from the surface of the fibres, which would then be covalently bonded to this surface from the moment of their creation.
[0024] In other words, the polymerization of the resin would trigger the activation of the groups grafted to the surface of the fibres to give active centres, this activation being accompanied both by control of the polymerization and by the creation of covalent bonds between the fibres and the organic matrix.
[0025] This presumed mechanism can be illustrated diagrammatically in the following way:
[0000]
[0000] where:
[0026] TA represents a group acting as chain transfer agent,
[0000]
[0000] represents a polymer chain,
[0027] stage (a) illustrates the conversion of this group to an active centre, and
[0028] stage (b) illustrates the formation of a new polymer chain starting from the surface of the fibre.
[0029] In accordance with the invention, the groups which are grafted to the surface of the carbon fibres and which are preferably all identical can be chosen from the many groups known for being capable of acting as chain transfer agents in a chain polymerization, it being understood that the selection will preferably be made of that or those which make(s) it possible to obtain a fibre/matrix bond which is the most satisfactory possible, in view of the curable resin which has to be used and/or the conditions under which the latter has to be polymerized.
[0030] In order to do this, it is entirely possible to evaluate the effect of different groups on the adhesion of carbon fibres with regard to a specific organic matrix and/or for specific polymerization conditions, for example by subjecting fibres on which one of these groups will have been grafted beforehand to a test conventionally used to assess the mechanical properties of a fibre/matrix interface, such as, for example, a loosening test of the type of that described in Example 1 below, and by comparing the results obtained for each grafted group.
[0031] Mention may in particular be made, as groups capable of acting as chain transfer agents in a chain polymerization, of carbon-based groups comprising an —I, —Br, —Cl, —F, —SH, —OH, —NH—, —NH 2 , —PH—, —PH 2 or ═S functional group and also carbon-based groups which are devoid of a heteroatom but which can give rise to radical transfer, such as, for example, optionally substituted allyl or benzyl —CH groups.
[0032] It turns out that, in the context of their studies, the Inventors have found that the grafting of carbon-based groups comprising a thiol functional group makes it possible to obtain a particularly significant improvement in the adhesion of carbon fibres, in particular with regard to matrices obtained by polymerization of epoxy acrylate resins under ionizing radiation. Consequently, carbon-based groups comprising a thiol functional group are those which it is preferable to graft in the context of the present invention.
[0033] Furthermore, in accordance with the invention, the grafting to the surface of the carbon fibres of the groups capable of acting as chain transfer agents is generally carried out by reacting functional groups present on this surface with a compound which generates, during this reaction, a group capable of acting as chain transfer agent or which comprises such a group, the choice of this compound being conditioned by the type or types of functional groups present at the surface of the fibres, which themselves depend on the treatment or treatments to which the fibres have been subjected during or on conclusion of the manufacture thereof.
[0034] Thus, for example, carbon fibres which have been subjected to an electrolytic or chemical oxidation carry, in principle, oxygen-based groups, such as hydroxyl, ketone, carboxylate or ether groups, while carbon fibres which have been subjected to sizing carry, for their part, generally epoxide groups.
[0035] It should be noted that, if it is not possible to obtain details on the type or types of functional groups carried by carbon fibres from the manufacturer, it is possible to assess the surface condition of these fibres by electron spectroscopy for chemical analysis (ESCA), also known under the name of X-ray photoelectron spectroscopy (XPS).
[0036] According to a first preferred embodiment of the process according to the invention, the grafting to the surface of the carbon fibres of the groups capable of acting as chain transfer agents is carried out by reacting functional groups present at the surface of these fibres with a cyclic organic compound which, by ring opening, becomes covalently bonded to the functional groups of the fibres and simultaneously generates a group capable of acting as chain transfer agent.
[0037] Thus, for example, in the case where it is desired to graft carbon-based groups comprising a thiol functional group to the surface of oxidized carbon fibres which comprise in particular carboxyl groups, this grafting is carried out by reacting these carboxyl groups with an episulphide which, by ring opening, becomes covalently bonded to a carboxyl functional group and simultaneously generates a group comprising a thiol functional group.
[0038] The episulphide is, for example, propylene sulphide, ethylene sulphide, cyclohexene sulphide, epithiodecane, epithiododecane or 7-thiabicyclo-[4.1.0]heptane and the reaction is advantageously carried out under hot conditions (for example, at a temperature of the order of 100° C.) in the presence of a catalyst, preferably a tertiary amine, such as triethylamine.
[0039] Furthermore, it is advantageously followed by one or more operations of washing the fibres and then by one or more operations of drying said fibres, which can be carried out according to procedures conventionally employed in the matter of washing and drying fibres and in particular carbon fibres.
[0040] According to another preferred embodiment of the process according to the invention, the grafting to the surface of the carbon fibres of the groups capable of acting as chain transfer agents is carried out by reacting functional groups present on the surface of these fibres with an organic compound which comprises a chemical functional group capable of reacting with the said functional groups and a group capable of acting as chain transfer agent.
[0041] Thus, for example, in the case where it is desired to graft carbon-based groups comprising a thiol functional group to the surface of the carbon fibres, this grafting is carried out by reacting the functional groups present at the surface of these fibres with an organic compound having a chemical functional group which is chosen as a function of the type or types of functional groups present at the surface of the fibres and a group comprising a thiol functional group.
[0042] For sized fibres rich in epoxide groups, the chemical functional group is advantageously a carboxyl or phenol functional group and the reaction is advantageously carried out under hot conditions (for example, at a temperature of 150° C.) under vacuum and in the presence of a catalyst, preferably a tertiary amine, such as dimethylaminoethyl methacrylate.
[0043] An organic compound having both a carboxyl functional group and a group comprising a thiol functional group is, for example, thiomalic acid, thioglycolic acid, thiolactic acid, 3-mercaptopropionic acid, 11-mercaptoundecanoic acid, 16-mercapto-hexadecanoic acid, 2-mercaptonicotinic acid, 6-mercaptonicotinic acid or 2-mercapto-4-methyl-5-thiazolacetic acid, while a compound having both a phenol functional group and a group comprising a thiol functional group is, for example, 2-mercaptophenol, 3-mercaptophenol, 4-mercaptophenol or 4-thiouracil.
[0044] In any case, it is within the normal competence of a person skilled in the art of the field of the coupling of chemical functional groups to know how to determine, according to the functional groups present at the surface of the carbon fibres which he intends to use, what are the compounds suitable for allowing him to graft, to the surface of these fibres, the groups of his choice and to fix the conditions under which the grafting has to be carried out in order to be effective, in particular as regards the carbon fibres/reactant(s)/catalyst(s) relative proportions which have to be used, and also the temperature and pressure parameters necessary for the satisfactory progression of this grafting.
[0045] In accordance with the invention, the curable resin can be chosen from any resin capable of curing by a chain polymerization mechanism, whether under the effect of heat or under the effect of light or ionizing radiation, this being because the Inventors have found, in the context of their studies, that the process according to the invention is effective both in the case of a thermosetting resin and of a photo- or radiation-curable resin.
[0046] However, for the reasons set out above, the resin is preferably chosen from resins which can be polymerized under radiation and in particular from resins of multiacrylates type, such as epoxy acrylates, novolac acrylates and polyurethane acrylates, bismaleimide resins and epoxide resins, epoxy acrylate resins being particularly preferred in the case where the composite material is intended for space or aeronautical applications.
[0047] Once the grafting to the surface of the fibres of the groups capable of acting as chain transfer agents has been carried out, the carbon fibres can either be used immediately in the manufacture of components made of composite materials or can be stored for the purpose of subsequent use or also be packaged for the purpose of their delivery to manufacturers of components made of composite materials. This is because the process according to the invention can be employed both by the manufacturers of carbon fibres and by the users thereof.
[0048] Another subject-matter of the invention is a process for the manufacture of a component made of composite material comprising carbon fibres and an organic matrix, which process comprises bringing the fibres into contact with a resin which can be cured by chain polymerization and then polymerizing the resin and is characterized in that it furthermore comprises the implementation of a process as described above before the fibres are brought into contact with said resin.
[0049] It is obvious that the manufacture of this component made of composite material can be carried out according to any technique known to a person skilled in the art of composite materials, such as, for example, simultaneous spray moulding, vacuum moulding, moulding by low pressure injection of resin (Resin Transfer Moulding (RTM)), low pressure “wet route” cold press moulding, compound injection moulding (Bulk Moulding Compound (BMC)), moulding by compression of preimpregnated mats (Sheet Moulding Compound (SMC)), filament winding moulding, centrifugal moulding or pultrusion moulding.
[0050] Other characteristics and advantages of the process for improving the adhesion of carbon fibres with regard to an organic matrix in accordance with the invention will become more clearly apparent on reading the remainder of the description which follows, which relates to examples of the implementation of this process and which refers to the appended drawings.
[0051] Of course, these examples are given solely by way of illustration of the subject-matter of the invention and do not under any circumstances constitute a limitation on this subject-matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] FIG. 1 illustrates the reaction between two carboxyl functional groups situated on the surface of an oxidized and nonsized carbon fibre and propylene sulphide in the presence of a tertiary amine and shows the chemical structures of the two types of groups comprising a thiol functional group which are assumed to become attached to the surface of the fibre during this reaction.
[0053] FIG. 2A shows a negative taken with a scanning electron microscope (SEM), at a magnification of 500×, of a split in a composite material produced from an epoxy acrylate resin and oxidized and nonsized carbon fibres.
[0054] FIG. 2B shows a negative taken with an SEM, at a magnification of 3500×, of a split in a composite material produced using the same epoxy acrylate resin and the same carbon fibres as those present in the composite material of FIG. 2A but after having grafted groups comprising a thiol functional group to the surface of these fibres by the reaction illustrated in FIG. 1 .
[0055] FIG. 3 illustrates the reaction between an epoxide functional group situated at the surface of a sized carbon fibre and thiomalic acid in the presence of a tertiary amine.
DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS
Example 1
[0056] This example relates to the grafting of groups comprising a thiol functional group to the surface of carbon fibres which have been subjected to electrolytic oxidation but which have not been subjected to any sizing.
[0057] These fibres originate from Tenax, which markets them under the reference IMS5001.
[0058] Their main chemical characteristics are collated in Table 1 below.
[0000]
TABLE 1
Elemental
C
O
N
atomic ratios
83%
15%
2%
Nature and
—COR
—C═O
—COOH
distribution of
9.5%
3.1%
6.3%
the oxygen-
based groups
(as % of the
total carbon)
[0059] The grafting of the groups comprising a thiol functional group to the surface of the fibres is carried out by reacting the carboxyl functional groups present on this surface with propylene sulphide in an organic solvent and in the presence of triethylamine according to the reaction scheme represented in FIG. 1 .
[0060] The solvent used is toluene, this being because its low polarity makes it possible to limit the occurrence of undesirable side reactions.
[0061] These various compounds are used at the level of:
[0062] 200 mmol of propylene sulphide,
[0063] 30 mmol of triethylamine,
[0064] 30 ml of toluene,
[0065] per 55 mg of carbon fibres.
[0066] The grafting reaction is carried out in a confined environment, without addition of pressure, at 100° C. and for 5 hours.
[0067] In practice, use is made of a steel reactor, of cylindrical shape, which is provided with a stirrer and a heater band which makes it possible to bring the reaction medium to and maintain it at the desired temperature. Furthermore, in order to prevent the fibres from becoming entangled around the stirrer, they are placed in the reactor by being enclosed beforehand in a nonwoven polypropylene bag which is permeable but resistant to toluene.
[0068] After reacting for 5 hours, the fibres are washed twice in an acetic acid/toluene (10/90 v/v) solution, in order to remove the triethylamine, and then washed five times in pure toluene, each washing operation being carried out in a beaker, with stirring and for 30 minutes.
[0069] The yield of the grafting reaction is assessed by subjecting the fibres to a Soxhlet extraction with water for 5 hours, so as to remove all the impurities liable to be present at the surface of the fibres, and by then carrying out an ESCA/XPS analysis of this surface. This analysis shows the proportion of the sulphide atoms present at the surface of the fibres as 3%.
[0070] The effect of the grafting of groups comprising a thiol functional group on the adhesion of the fibres with regard to a matrix obtained by polymerization of an epoxy acrylate resin, in the case in point the resin EB600 from UCB Chemicals, is for its part assessed by a loosening test.
[0071] In brief, this loosening test consists in immersing the end of a monofilament in a microdrop of resin, in bringing about the polymerization of the resin at ambient temperature and under an electron beam and in then exerting a tensile stress on the other end of the monofilament, at the rate of 1 mm/min, while keeping the drop of resin stationary.
[0072] The tensile force is recorded over time. The maximum tensile force recorded is regarded as the force necessary for the loosening of the monofilament from the cured resin drop.
[0073] The InterFacial Shear Strength (IFSS) is determined using the following formula:
[0000]
τ
=
σ
fd
2
L
=
F
2
π
rL
[0000] in which:
[0074] d represents the diameter of the monofilament (in metre),
[0075] r represents the radius of the monofilament (in metre),
[0076] L represents the length of monofilament initially inserted into the drop of resin (in metre),
[0077] F represents the force necessary for the loosening of the monofilament from the cured resin drop (in newton), and
[0000]
σ
f
=
F
π
r
2
(
in
newton
/
m
2
)
.
[0078] The loosening test is carried out on several monofilaments of IMS5001 fibres which have been grafted with groups comprising a thiol functional group and several monofilaments of IMS5001 fibres which have not been grafted, so as to be meaningful.
[0079] The results show that the IFSS is 59±3 MPa in the case where the IMS5001 fibres were grafted to groups comprising a thiol functional group, whereas it is only 49±4 MPa in the case where the IMS5001 fibres were not grafted.
[0080] The IFSS is thus increased by 20% by the presence of thiol functional groups on the surface of the fibres.
[0081] The positive effect of the grafting of the groups comprising a thiol functional group on the fibres/matrix adhesion is furthermore confirmed by an SEM analysis of splits in composite materials comprising a matrix obtained by polymerization of EB600 resin and IMS5001 fibres which are or are not grafted with groups comprising a thiol functional group.
[0082] These composite materials are produced in the form of unidirectional sheets by:
impregnation of the fibres with the resin (degree of impregnation 40% by weight); manufacture of unidirectional plies (12 plies) by winding the impregnated fibres around a flat mandrel; assembling the plies by drape moulding and compacting; polymerization under vacuum at ambient temperature by 4 passes at 25 kGy.
[0087] As is shown in FIG. 2B , which corresponds to a negative taken at a magnification of 3500× of a split in a composite material including IMS5001 fibres grafted with groups comprising a thiol functional group, these fibres exhibit resin residues attached at their surface which are not found on the fibres of a composite material including IMS5001 fibres not grafted with groups comprising a thiol functional group ( FIG. 2A ) and which testify to better bonding between the fibres and the epoxy acrylate matrix.
Example 2
[0088] This example for its part relates to the grafting of the group comprising a thiol functional group to the surface of sized carbon fibres.
[0089] These fibres originate from Toray, which markets them under the reference T800H40.
[0090] They exhibit a sizing agent of epoxide type and more specifically of bisphenol A diglycidyl ether (BADGE) type, this being because these fibres are intended to be used mainly with epoxide resins.
[0091] The groups comprising a thiol functional group are grafted to the surface of fibres by reacting the epoxide functional groups present on this surface with thiomalic acid in the presence of dimethylaminoethyl methacrylate according to the reaction scheme represented in FIG. 3 . The solvent used is methyl ethyl ketone.
[0092] To do this, the fibres, in the form of a bobbin, are impregnated with a mixture of thiomalic acid and of amine, in a molar ratio of the amine functional groups to the carboxyl functional groups of 0.5%, diluted to 0.7% by weight in methyl ethyl ketone, and then the impregnated bobbin is subjected to a heat treatment at 150° C. for 30 minutes, after a rise in temperature over 45 minutes.
[0093] The effect of the grafting of the groups comprising a thiol functional group on the adhesion of the fibres with regard to a matrix obtained by polymerization of an epoxy acrylate resin, in a case in point the EB600 resin, is assessed by subjecting composite materials, produced according to a protocol analogous to that described in Example 1 from this resin and T800H40 fibres grafted or not grafted with groups comprising a thiol functional group, to a transverse bending test according to Airbus Standard IGC.04.06.245 or Standard EN 2582.
[0094] The results show that the bending σ2 is 70 MPa in the case where the T800H40 fibres were grafted with groups comprising a thiol functional group, whereas it was only 25 MPa in the case where the T800H40 fibres were not grafted.
DOCUMENTS CITED
[0000]
[1] JP-A-3076869
[2] EP-A-1 484 435
[3] EP-A-0 640 702
[4] JP-B- 2002327374
[5] Wu et al., Carbon, 34, 59-67, 1996
[6] Tsubokawa, Carbon, 31, 1257-1263, 1993 | The invention relates to a process for improving the adhesion of carbon fibres with regard to an organic matrix forming a composite material with these fibres, this composite material being obtained by bringing the fibres into contact with a resin which can be cured by chain polymerization and then polymerizing the resin, which process is characterized in that it comprises the grafting, to the surface of the fibres, before they are brought into contact with the resin, of groups capable of acting as chain transfer agents during the polymerization of said resin.
Fields of application: aeronautical, aerospatial, railway, ship building and automobile industries but also the armaments industry, the industry of sports and leisure articles, and the like. | 3 |
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention is closely related to and represents an improvement over our prior U.S. Pat. No. 3,863,579. That patent is directed to an improved mechanism, for attachment to a conventional industrial sewing machine, for feeding oriented buttons to a sewing station for securement to a garment. The mechanism of our prior patent is arranged to be mounted on a conventional sewing machine and to be mechanically actuated by a cam mechanism driven from the sewing machine drive, enabling the auxiliary mechanism to be actuated through a predetermined series of steps involved in the button feeding and orienting operation.
In accordance with the present invention, the button feeding and oriented system of our prior patent is improved and made more simple and economical by incorporating an improved form of actuating system for the button feeder, which is pneumatically, instead of mechanically actuated. By utilizing the new form of pneumatic actuation, instead of a mechanical association with the sewing machine, not only is the mechanism itself simplified, but its attachment to and incorporation with the sewing machine is rendered much more simple and economical. In this respect, it is contemplated that, while the button feeding and orienting mechanism will be in the nature of a permanent or semi-permanent attachment to the sewing machine, important savings in the equipment cost may be realized by minimizing the modifications required to be made to an otherwise standard commercial sewing machine in order to accept the button mechanism.
In accordance with one particularly advantageous feature of the invention, the new button mechanism is arranged to be incorporated in a standard commercial sewing machine of a type provided in the first instance with a pair of controllably sequenced pneumatic cylinders, which are associated with the raising and lowering of the presser foot and the commencement and termination of the sewing cycle. The button feeding and orienting system of the present invention is so arranged and constructed that the pneumatic cylinders employed in the mechanism are actuated by, in effect, simply tapping off of the fluid chambers of the main air cylinders incorporated in the sewing equipment itself. Thus, as the primary sewing machine cylinders are pressurized and exhausted in the course of a cycle of sewing operations, the primary control pressures are utilized in a unique and advantageous manner to effect properly timed actuation of the button feeding and orienting mechanism. In this manner, a rather complex series of operations involved in the button feeding and orienting are accomplished and, in addition, are properly synchronized with the sewing cycle, in an extraordinarily simplified, economical and reliable manner.
In another form of the invention, adapted specifically for incorporation with a different form of commercial sewing machine, not provided with primary air actuators, a unique and highly simplified pneumatic valving arrangement, having a mechanically timed association with the sewing cycle, is provided for effecting the desired sequence of operations of the button feeding and orienting mechanism.
For a more complete understanding of the above and other features and advantages of the invention, reference should be made to the following detailed description of preferred embodiments of the invention, and to the accompanying drawing.
DESCRIPTION OF THE DRAWING
FIG. 1 is a front elevational view of a conventional, commercial sewing machine incorporating the improved button feeding and orienting system of the invention.
FIG. 2 is a side elevational view of the apparatus of FIG. 1.
FIG. 3 is a top plan view illustrating the button feeding and orienting mechanism of the invention.
FIG. 4 is a fragmentary cross sectional view as taken generally on line 4--4 of FIG. 3.
FIG. 5 is a simplified, schematic piping diagram illustrating a novel manner of incorporating sequenced pneumatic actuation of the button mechanism into the primary pneumatic actuation of the sewing machine.
FIG. 6 is a fragmentary elevational view illustrating the manner in which a modified form of the system of the invention is incorporated in a standard sewing machine not having pneumatic actuation.
FIG. 7 is a simplified schematic piping diagram of the button feeding and orienting mechanism incorporated with the sewing machine of FIG. 6.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawing, and initially to FIGS. 1-4 thereof, the reference numeral 10 designates in a most general way a typical commercial industrial sewing machine. By way of example, the sewing machine 10 may be a Singer Model 421, W307BA industrial type machine, which includes a base 11, pedestal 12, overhanging arm 13, needle 14 and presser foot support 15. A sewing machine of the type designated is typically arranged for operation in cycles, by means of a suitable control cam (such as indicated at 16). By means to be further described, when a sewing operation is commenced, as by actuation of a foot control valve or the like, a cycle of sewing is commenced during which, in a conventional machine, the presser foot is lowered onto the work and sewing is commenced and continued until the control cam 16 has completed a cycle, after which the sewing mechanism is disengaged from the drive motor and the presser foot is raised to permit removal of the work.
The illustrated machine is modified from its standard commercial version by attachment of a button feeding and orienting device of the general type described in our prior U.S. Pat. No. 3,863,579. To this end, a clamping spring 17 is mounted adjacent the sewing machine pedestal 12 and extends forward toward the sewing station. At its forward end, the clamping spring 17 mounts a button feeding bracket 19, which is provided with an open-ended guide slot 20 of a size suitable to receive buttons 21 of a predetermined size. The buttons 21 are supplied from a suitable means, such as a Syntron-type feed hopper (not shown), which discharges the buttons one by one down through a hollow chute, formed by a spring-like member 22.
At the outer end of the button feed bracket 19, there is a button clamp section 23 mounted on a spring 24 and provided with an arcuate recess 25 for gripping a button in the sewing position and holding it while a sewing operation is performed to secure the button to an underlying section of fabric.
As set forth more particularly in our before mentioned patent, a button in the load position L is arranged to be engaged by a plurality of downwardly extending short pins (not shown) which are adapted to enter the holes 27 in the button. The pins are mounted on a rotatable pinion 28 supported in a feeding head 29 and driven by a gear 30, which is also mounted in the feeding head.
As illustrated particularly in FIG. 3, the feeding head 29 is secured in fixed relation to a support tube 31, which is mounted for limited axial sliding and rotating movement in a bearing block 32. Stop collars 33, 34 are fixed to the support tube 31 and serve to limit the extent of its sliding movement. When the forward collar 33 engages the block 32, the feeding head 29 is stopped in the load position L; when the rearward stop collar 34 engages the block 32, the feeding head is located in the sewing position S.
A short sleeve 35 is fixed to the end of the support tube 31, and a pin 36 extending radially from the sleeve engages one end of a tension spring 37. The other end of the spring is engaged by a pin 38 anchored to the sewing machine base. The arrangement and disposition of the spring 37 is such as to tend to draw the support tube 31 in a rearward direction and to rotate it in a direction to urge the feeding head 29 downward toward the button in the feed bracket 19.
An actuating rod 39 is slideably and rotatably supported at one end in a bearing bracket 40 and extends forward through the sleeve 35 and through the support tube 31 up to the feeding head 29. At its forward end, the actuating rod forms a rack 41, which engages the gear 30 and is adapted to rotate the gear 30 and the pinion 28 upon relative sliding movement of the actuating rod 39 with respect to the support tube 31.
The normal position of the actuating rod 39 within the support tube 31 is established by a stop pin 42 anchored in the actuating rod 39 and extending through an elongated slot 43 in the sleeve 35. A spring 44 is anchored at its forward end to the sleeve 35, by means of the pin 36, and at its rearward end to the actuating rod 39, by means of a pin 45. Accordingly, the normal position of the actuating rod is determined by the pin 42 engaging the forward end of the slot 43.
The function of the button feeding mechanism, as thus far described, is as follows: The springs 37 and 44 initially hold the support tube 31, feeding head 29 and actuating rod 39 in the position illustrated in FIG. 3, it being assumed at this stage of the explanation that the button directly underneath the feeding head has been engaged by orienting pins and is properly rotationally oriented. When it is time to feed a new button into the sewing position S, the actuating rod 39 is driven forward (by means to be described) until the stop collar 34 engages the bearing block 32. The button engaged by the orienting pins is carried forward in the feed bracket 19 and is snapped into place in the clamp 23. At this time, the support tube 31 and actuating rod 39 are rotating slightly (by means to be described) to lift the feeding head 29 and withdraw the orienting pins from the thread holes 27 of the button now in the sewing station S. By means of the spring 37, the support tube 31 is retracted until the forward stop collar 33 engages the bearing block 32. The spring 37 also at this time urges the orienting pins downward onto a new button, which has in the meantime been advanced along the feed bracket 19 into the load position L. Proper engagement of the new button by the loading head and orienting pins is achieved by a momentary rearward reciprocation of the actuating rod 39, against the spring 44. Since the support tube and loading head are stopped by the collar 33, the actuating rod 39 moves relative to the support tube and causes rotation of the gear 30 and pinion 28 and, of course, corresponding rotation of the orienting pins. Assuming that the orienting pins have not initially entered the thread openings 27 in the button, they will do so after a short initial rotation of the pinion 28, whereupon the spring 37 causes the loading head 29 to drop down toward the button and mechanically engage the button with the orienting pins. Return movement of the actuating rod 39 is effected by the spring 44, which rotates the gear 30 and pinion 28 back to a predetermined starting orientation, in which the orienting pins, and therefore the button 21, will be properly rotationally oriented in preparation for a subsequent sewing operation. In this respect, forward movement of the actuating rod 39 is always limited by engagement of the pin 42 and slot 43, so that repetitively precise rotational orientation of the button is assured.
The various above described motions of the button feeding and orienting mechanism are achieved, in accordance with the present invention, by means of a pair of pneumatic actuators 50, 51. The actuator 50 is a double acting unit, having air lines 113, 111 leading to each end of the cylinder, and having a forwardly extending operating rod 54 engaging a drive arm 55 through a spherical bearing member 56. The closed end of the actuator 50 is secured to the frame of the sewing machine, also by a spherical or other bearing 57, which will accommodate at least limited movement of the actuator about multiple axes. The drive arm 55 may be welded or otherwise secured to a collar 55 fixed to the actuating rod 39.
Advantageously, the operating rod 54 of the actuator 50 has an extension 59, which has a sliding fit with the spherical bearing 56 on the drive arm. Forward and rearward stop collars 60, 61 are secured to the rod extension 59, on opposite sides of the bearing 56, preferably with some clearance at each side.
When both ends of the feed actuator 50 are deactivated, the button feeding mechanism is retained in its normal position, as shown in FIG. 3, and the piston 62 of the actuator 50 will be more or less centered within the cylinder, being moved to such position by return of the drive arm 55 and bearing 56 to normal positions, under the influence of the springs 37, 44.
Forward feeding of a button from the load position L to the sewing position S is effected by admitting fluid pressure into the closed end of the actuator 50 through air line 111. As will be further described, forward energization of the actuator 50 is only momentary, sufficient to drive the support tube 31 forward to its limit stop, after which the support tube is rotated slightly to upwardly tilt the loading head 29 and free and just-delivered button. As the closed end of the actuator 50 exhausts, following its momentary actuation, the spring 37 returns the support tube 31 to its normal position.
At some point in the cycle, prior to the next button delivery operation, the rod end of the actuator 50 is energized by admitting pressure fluid into the line 113 to effect a momentary retraction of the operating rod 54. This serves to retract the actuating rod 39 against the spring 44, to effect pin engagement with a button as heretofore described. Following the momentary energization and exhausting of the rod end of the actuator 50, the actuating rod 39 is returned by the spring to its normal position, with a new button now being engaged and oriented by the loaded head 29.
Properly timed rotation of the support tube 31 and corresponding upward tilting of the loading head 29 is achieved by means of a single acting, spring returned air cylinder 51, which is mounted vertically on the machine, by means of a support bracket 63. The upper or closed end of the actuator 51 is connected through a fluid line 112 and metering valve 65 to a controlled source of pressure fluid, as will be further described. Location of the actuator 51, which may be referred to as the tilt actuator, is generally directly above the forward-actuated position of the drive arm 55 (as shown in phantom lines in FIG. 3). Accordingly, when the feed actuator 50 is energized forwardly, advancing the drive arm 55 to its forward position to deliver a button into the sewing position, the tilt actuator 51 is energized to extend its operating rod 65a downward. A pusher bar 66 carried by the operating rod 65a engages the forwardly advanced drive arm 55 and pushes it downward, as shown in FIG. 4, rotating the actuating rod 39, sleeve 35 and support tube 31 and lifting the loading head 29 in the desired manner. A suitable adjustable limit stop 67 (FIG. 4) may be provided to limit the amount of rotation of the support tube 31.
As reflected in FIG. 3, the length of the pusher head 66, in a direction parallel to the actuating rod 39, is somewhat less than the actuating stroke of that rod during the forward movement in delivering a button. Thus, on the return or rearward movement of the actuating arm 39, the drive arm 55 will clear the pusher head 66 and be permitted to rotate in a return direction under the influence of the spring 37. The length of the pusher head 66 is sufficient to retain the loading head 29 in its tilted or raised position until it has cleared the just-delivered button and is positioned over the top of a new button in the load position.
In a normal button-sewing cycle, the fabric on which the button is to be sewed is clamped in the sewing machine prior to commencement of sewing. This is accomplished in the illustrated apparatus by means of the spring 17, which presses a clamping foot 68 (FIG. 2) downward onto the fabric part. At the conclusion of the sewing cycle, the presser foot lift bar 15 is raised, as a normal part of the sewing cycle. In the illustrated apparatus, a lifting finger 69 extends upward from the button feed bracket 19 and overlies an arm 70a of the presser foot lift bar. Thus, when the bar 15 is raised, at the conclusion of sewing, the clamping foot 68 is lifted to free the completed article with the attached button. Before commencement of the next cycle, a new piece of fabric is inserted under the clamping foot, and the cycle commences with the lowering of the presser foot lift bar 15, allowing the spring 17 to bring the clamping foot 68 into engagement with the fabric.
Pursuant to an important aspect of the invention, a unique and simplified arrangement is provided for associating and synchronizing the operations of the feed and tilt actuators with the functions of the sewing machine during the sewing cycle. A particularly advantageous arrangement is made possible by the invention when incorporated with a sewing machine of the general type reflected by Singer Model 421, W307BA (hereinafter referred to as Model 421), which are widely used for industrial sewing. The Model 421 sewing machine is conventionally provided at the back with a pair of pneumatic actuators 70, 71 (FIG. 5) which may be referred to respectively as the clamp and clutch cylinders. The clamp cylinder 70 is provided with an upwardly extending operating rod 72 which operates (by conventional means not shown), a drive shaft 73 (FIG. 2) operating the presser foot lift bar 15. The arrangement is such that, when the clamp cylinder operating rod 72 is extended (raised) the presser foot lift bar 15 is lowered, serving in the instant case to lower the clamping foot 68 onto the work. The clutch cylinder 71 has an operating rod 74 which, in the commercial form of the Model 421 sewing machine is connected to a clutch-brake mechanism of the sewing machine. When momentarily actuated in an upward or extending direction, the operating rod 74 serves to release the sewing machine brake and simultaneously engage a clutch, connecting the drive motor to the sewing mechanism. The standard commercial sewing machine further includes a mechanical cam type lock (not shown) which retains the clutch operating rod 74 in an extended condition, regardless of the application of fluid pressure in the return direction, until a complete sewing cycle has been concluded. At that time, fluid pressure, previously applied to the upper end of the clutch cylinder 71, is effective to retract the mechanically released operating rod 74 to conclude the sewing cycle.
As part of the standard equipment of the Model 421 sewing machine, the clamp and clutch cylinders 70, 71 are associated with crossover valves 75, 76, which are three-way fluid valves arranged to be actuated by upward or extending movements of the respective operating rods 72, 74 and cross connected to the respective cylinders. Thus, upward movement of the clamp cylinder rod 72 will effect actuation of the crossover valve 75, which is connected to the clutch cylinder 71, and upward movement of the clutch cylinder rod 74 will effect actuation of the crossover valve 76, which is cross connected to the clamp cylinder 70.
In general, in the operation of a standard, conventional Model 421 machine, a foot valve 77 is depressed by an operator to commence a sewing operation. This results in exhausting fluid under relatively high pressure from the upper end of the clamp cylinder 70, causing the operating rod 72 to extend under the influence of low pressure constantly applied to the closed end of the cylinder. In a conventional machine, this would serve to lower the presser foot. Extension of the cylinder 70 raises a bracket 78 carrying a pedestal bolt 79 arranged for engagement with an operator 80 for actuating the three-way crossover valve 75. Thus, when the clamp cylinder 70 is fully extended, which in the illustrated system serves to lower the presser foot support 15, the clamping foot 68 is also lowered. As the clamping operation is completed, the crossover valve 75 is actuated to effect momentary retraction of the initially extended clutch cylinder rod 74. This is mechanically held in a retracted position until the end of a sewing cycle, after which it is mechanically released and allowed to extend. At that time, a bracket 81 carried with the rod 74 engages a valve actuator 82 for the second crossover valve 76. This admits pressure to the upper end of the clamp cylinder 70 releasing the fabric and ending the cycle of operations.
As thus far described, the fluid operating system is a standard part of the conventional Model 421 sewing machine. Pursuant to the invention, unique and advantageous utilization is made of the existing control functions of the Model 421 machine such that, by judiciously tapping off of the existing control pressures, the button feed actuator 50 and the tilt actuator 51 may be caused to operate in desired synchronism with the other functions of the sewing machine, with a practical minimum of added control components. With reference still to the schematic diagram of FIG. 5, a regulated source of air under pressure is derived from an air supply line 83 leading through a main pressure regulator 84. This air, which may be at a pressure of, say, 60 psi, may be considered as the primary control air. Secondary control air, at a lower pressure of about five psi, is derived from a second pressure regulator 85. The secondary control air is led through fluid lines 86, 87 to the closed ends of the clamp and clutch cylinders 70, 71 respectively, and provide a constant upward pressure bias on those cylinders. Primary air, at the higher pressure, is led through a fluid line 88 to the inlet side of the foot valve 77. The foot valve incorporates a pair of three-way valves (not specifically illustrated) connected respectively to outlet lines 89, 90. The outlet line 89 is connected to a normally open valve and is normally under primary pressure. The outlet line 90 is connected to a normally closed valve, and is normally exhausted.
The normally exhausted outlet line 90 is connected to the inlet side of the first crossover valve 75 and, through that valve, is connected by means of a fluid line 91 to a one-shot pulse valve 92, which in turn is connected to the upper or rod end of the clutch cylinder 71.
When the foot valve 77 is depressed, pressure is admitted to the fluid line 90 and thus to the inlet side of the crossover valve 75. The crossover valve is normally closed and does not admit fluid to its outlet line 91. However, when the crossover valve is actuated, by upward movement of the clamp actuator rod 72, pressure fluid is admitted to the line 91 and one-shot pulse valve 92. This serves to admit a single pulse of high pressure air to the upper end of the cylinder 71. This high pressure air overcomes the lower pressure bias at the closed end of the cylinder, retracting the cylinder rod 74 until it is mechanically locked by the sewing machine mechanism. During the sewing cycle, the upper end of the clutch cylinder 71 is exhausted through the one-shot valve 92, permitting return of the arm 74 when mechanically released by the sewing machine.
When the foot valve 77 is depressed, pressure is exhausted from the line 89. Through a system of valves to be described, and the purpose of which it is to provide for automatically repetitive operation of the system, pressure is at this time also exhausted from the fluid line 93 leading to the upper end of the clamp cylinder 70, causing that cylinder to extend and, eventually, to actuate the crossover valve 75.
In the illustrated control system, including the automatic repeat feature, the outlet line 89 from the foot valve is connected to a control valve 94. The control valve is also connected to a line 95 and through a Tee fitting 96 to a fluid line 97 connected to the line 93 leading to the upper end of the clamp cylinder 70. Also connected in the line 93 is a so-called dump valve 98 which is operative, when pressure is being exhausted from the line 93 to "dump" or rapidly exhaust the upper end of the clamp cylinder. Thus, in the illustrated system, when pressure is relieved from the line 89 by the foot valve 77, the valve outlet line 95 is connected through the control valve 94 to a restricted exhaust outlet 99. However, as soon as a partial loss of pressure has been realized in the line 93, the dump valve 98 will actuate to rapidly exhaust the balance.
In the illustrated system, the inlet side of the second crossover valve 76 is supplied with primary (high pressure) air through a line 100. Initially, at the start of a sewing cycle, the crossover valve 76 is in an actuated condition, as a result of the normally extended position of the clutch cylinder rod 74. Accordingly, high pressure fluid is in the outlet line 100, leading from the crossover valve 76. The line 100 is connected at 101 to the control valve 94, and is also connected through lines 102, 103 and 104 to a control valve 105 and a metering valve 106 respectively. The outlet side of the metering valve 106 is connected through a line 107 to a control port of the valve 105. An outlet port of the valve 105 is connected through line 108 to the Tee fitting 96 and thus to the upper end of the clamp cylinder 70. Initially, the control valve 105 is closed at the start of a sewing cycle, so that high pressure fluid does not flow into the line 97.
At the commencement of a cycle of operations, after the clamp cylinder 70 has been extended following operation of the foot valve and the first crossover valve 75 has been actuated to retract the clutch cylinder 71, the second crossover valve 76 is deactuated and closed. Pressure in the line 100 and in the lines downstream thereof is permitted to bleed off. When the sewing cycle is completed, and the clutch cylinder rod 74 is mechanically released and permitted to extend, the second crossover valve 76 is reactuated, admitting pressure fluid into the lines 100 and 102-104. Primary pressure is thereupon admitted to the upper ends of the clamp cylinder 70 through the control valve 94. This retracts the clamp cylinder to its normal, starting position and releases the fabric from underneath the clamping foot 68. A new cycle can be started by subsequently depressing the foot valve 77.
If a continuing sequence of sewing cycles is desired, the foot valve 77 is held in a depressed condition, maintaining the outlet line 89 therefrom connected to exhaust. Under these conditions, when the sewing cycle is completed and the clutch actuating rod 74 mechanically released and extended to actuate the crossover valve 76, primary pressure is admitted to the upper end of the clamp cylinder 70 through the control valve 105, entering through the inlet line 103 and passing through the outlet line 108 into the Tee fitting 96. At the same time, primary pressure flows to the metering valve 106 and out into the metering valve outlet line 107 at a controlled rate. When full primary pressure is established in the line 107, after a predetermined time delay, the control valve 105 is closed and the primary pressure begins to bleed from the upper end of the clamp cylinder 70, actuating the quick dump valve 98 and initiating an entire new cycle. The time delay introduced by the valve 106 is controllable by metering control 110, to establish a sufficient time delay for the operator to remove the sewed button from the button clamp and either reposition the fabric for sewing of an additional button thereon or to introduce a new piece of fabric into sewing position.
In accordance with a significant aspect of the invention, the button feed actuator 50 and tilt actuator 51 are connected into the air actuating and control system for the sewing machine in such manner as to achieve the various button feeding and orienting operations in an automatically timed sequence with the sewing machine functions, without the need for additional complicated sequencing controls. To this end, the closed end of the button feed actuator 50 is connected by an air line 111 to the upper end of the clamp cylinder 70, between the cylinder and the dump valve 98. Thus, at the commencement of a cycle of sewing operations, when the upper end of the clamp cylinder 70 is pressurized, the closed end of the button actuator is also pressurized, holding the button feeding head 29 in an advanced position. In addition, the upper or closed end of the tilt actuator 51 is connected by a line 112 to the line 111, so it too will be pressurized and extended, such that the loading head 29 will be in an upraised position, with the orienting pins withdrawn from the previously delivered button.
Upon operation of the foot valve 77, resulting in pressure dumping from the upper end of the clamp cylinder 70, the clamping foot will be lowered, along with the just-delivered button. The loading head 29 will be withdrawn by the action of the return spring 37 and, upon clearing underneath the presser bar 66, will also rotate back to its normal position, ready to engage a new button. Exhausting of the line 111 will also, but at a slower rate, exhaust the upper end of the tilt cylinder 51 allowing it to retract.
The forward end of the button feed actuator 50 is connected via an air line 113 to the upper end of the clutch cylinder 71. Accordingly, after initiation of the operating cycle and completion of the clamping operation by upward extension of the cylinder rod 72, the crossover valve 75 is actuated, followed by actuation of the one-shot pulse valve 92. This serves momentarily to retract the clutch actuator rod 74, engaging the drive clutch to commence sewing of the button. This same one-shot pulse of primary pressure is directed through the air line 113 and serves to momentarily retract the actuator rod 39 of the button mechanism. As previously described, this results in a momentary rotation of the pinion 28 and orienting pins, first in one direction and then the other, to engage a button and rotationally orient it in the desired manner. The button is at that stage engaged, oriented and ready for loading.
Assuming there is to be a continued series of sewing operations, with the foot valve 77 remaining depressed, termination of one sewing operation, by mechanical release of the clutch operating rod 74 results in repressurizing the upper end of the clamp cylinder 70. This lifts the clamp from the just-sewed article and enables it to be withdrawn with the sewed on button. At the same time, primary pressure is directed through the lines 111, 112, extending the button feed actuator 50 to deliver the newly engaged and oriented button. The tilt actuator 51 is likewise actuated, but after a predetermined delay established by adjustment of a metering screw 114. The metering screw is set to permit the drive arm 55 to move underneath the pusher bar 66, and for the feeder head 29 to complete its forward advance, so that the button is properly positioned in the sewing station S before the feeding head is disengaged.
As will be apparent, the installation and operation of the button feed actuating system, comprising the button feed actuator 50 and the tilt actuator 51 is made extraordinarily simple and economical by effective utilization of the control pressures otherwise conventionally utilized in operating the sewing machine. The initial release of pressure from the upper end of the clamp cylinder 70 is utilized for retraction of the button feed mechanism and the tilt mechanism, leaving a just-delivered button exposed in position ready for sewing. A one-shot pulse of air, utilized to commence mechanical sewing operations, is also utilized to advantage to effect a one-shot reciprocation of the actuating rod 39, for engagement and orientation of a new button during sewing of a preceding button. Then, when the sewing operation is mechanically concluded, repressurization of the upper end of the clamp cylinder is utilized to deliver a new, oriented button to the sewing station and thereafter, in sequence, to tilt the feeding head and disengage the button. The sequencing of the tilt actuator 51 is done independently of the conventional sewing machine controls, by the simple expedient of a metering valve 114 in the inlet to the tilt actuator 51.
In the arrangement described in FIGS. 1-5, a button feeding and orienting mechanism having all of the advantageous mechanical features described in our prior U.S. Pat. No. 3,863,579, is made significantly more versatile and more economical to set up and service through the utilization of pneumatic actuators connected directly into the pneumatic actuating system for the sewing machine proper. For some relatively more simple models of sewing machine, the pneumatic actuating system of the Model 421 may not be available. Nevertheless, it is still possible to make advantageous use of a pneumatically actuated button feeding and oriented mechanism of the type described in FIGS. 1-4 by appropriately deriving pneumatic signals from mechanical functions of the sewing machine. A particularly advantageous arrangement for this purpose is reflected in FIGS. 6 and 7. In FIG. 6, the reference numeral 200 designates generally a conventional commercial sewing machine such as a Singer Model No. 275 machine. In FIG. 6, only the pedestal 201, base 202, and drive box 203 are shown, it being understood of course that the sewing machine 200 includes the principal operating components shown in FIGS. 1-4, including a button orienting and feeding mechanism and button feed and tilt actuators 50, 51 respectively therefor.
With the Model 275 machine, a sewing cycle is commenced by depressing the foot control 204 which serves, by means not shown but forming part of the sewing machine mechanism, to lower the clamp and engage the drive clutch. The sewing cycle is controlled by a timing cam 205 which cooperates with a control lever 206 such that, after commencement of a sewing cycle, the cam 205 goes through a single revolution until the follower reel 207 on the control arm 206 drops into a notch 208 on the control cam to terminate the cycle.
Pursuant to the invention, the pneumatic control system for use in connection with the Model 275 machine advantageously includes a line source 208a of air under pressure, passing through a regulator 209 and into a four-way valve 210. Alternate outlets from the four-way valve 210 are lines 211 and 212 respectively, one of which is pressurized and the other exhausted, depending on the actuated condition of the four-way valve. The outlet line 211 is connected to a one-shot pulse valve 213, and the outlet of that valve is connected through a line 214 to the closed end of the button feed actuator 50 and, through a line 215 and metering valve 216, to the closed end of the tilt cylinder 51. The outlet line 212 is connected to a one-shot pulse valve 217, and the outlet of that valve is connected through a line 218 into the rod end of the button feed actuator 50.
At the commencement of a sewing cycle, with the Model 275 type machine, the foot actuator 204 is depressed, mechanically engaging the sewing machine mechanism and commencing rotation of the cam 205. This immediately lifts the control lever 206 out of the cam notch 208, initiating sewing operations through control shaft 219. At the same time, by means of a bracket 220, mounted on the sewing machine control lever 206, the four-way valve 210 is actuated to pressurize the line 212 and admit a pulse of air to the rod end of the actuator 50, through line 218. This serves to momentarily retract the drive arm 55, and with it the actuating rod 39, and this operates to effect engagement and orientation of a new button, as previously described.
Throughout the sewing cycle, the sewing machine control lever 206 is mechanically held in its lifted position by the circular surface of the cam 205. After completion of the sewing cycle and release of the clamping foot, the control cam 205 completes its cycle, and the follower 209 drops back into the notch 208. Mechanically, this disengages the sewing machine drive and terminates the sewing machine cycle. At the same time, the rocking of the control lever 206 actuates the four-way valve 210 to its second operating condition, relieving pressure from the line 212 and admitting working pressure to the line 211. This results in a one-shot pulse of fluid pressure from the valve 213, entering the lines 214, 215. This pressure pulse enters the closed end of the button feed cylinder 50, momentarily extending the actuator rod 54 and advancing the support tube 31 and feeding head 29, to bring a new button into the sewing position. Simultaneously, the pressure pulse is admitted into the upper end of the tilt actuator 51, through the metering valve 216. The rate of fluid admission through the metering valve 216 is such that the tilt actuator 51 becomes operative to tilt the feeder head 29 after the new button has been delivered to the sewing station and before the return movement of the feeder head has commenced. In practice, this is just a momentary delay, as the forward actuation of the support tube 31 is virtually instantaneous.
In either of the forms of the invention, the button feeding mechanism of the type described in our before mentioned patent is made more universally applicable to a variety of industrial sewing machines, with a minimum of modification to the machines. By providing for actuation of the button mechanism utilizing simple fluid actuators, in place of cam and linkage mechanisms, attachment of the machine is rendered almost universal, notwithstanding variations from machine to machine. The simplest kinds of brackets may be utilized to anchor the fluid actuators to the sewing machine structure.
Additional and even more significant advantages may be realized in connection with sewing machines of the type utilizing a pair of fluid actuators for control of the presser foot and drive clutch. For those machines, the system of the invention enables the fluid actuators of the button mechanism to be tapped directly into appropriate lines of the existing control system, such that controlled fluid pressures already provided for in connection with sewing machine operation may also be utilized for timed, synchronized actuation of the button mechanism.
Where the sewing machine does not employ air cylinder actuation, but utilizes a cycle control cam, a simple and inexpensive modification enables a four-way control valve to be actuated from the primary control cam. This in turn controls the operation of a pair of pulse valves for properly timed operation of the fluid actuators of the button mechanism.
It should be understood, of course, that the specific forms of the invention herein illustrated and described are intended to be representative only, as certain changes may be made therein without departing from the clear teachings of the disclosure. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention. | The disclosure is directed to improvements in automatic mechanisms for feeding properly oriented buttons to the sewing station of a sewing machine, in preparation for sewing on a garment. The system utilizes a highly simplified pneumatic actuating system for both feeding and orienting the buttons. The system of the invention is arranged to accommodate a multiplicity of mechanical operations involved in button feeding and orienting, utilizing a simple arrangement of two pneumatic actuators, which are energized in timed sequence by pulses of air derived from operation of the sewing machine. In one of its most advantageous forms, the system of the invention derives the necessary timed energizing pulses of air from control air cylinders which form part of the basic sewing machine mechanism itself. Thus, adaptation of a conventional industrial sewing machine to incorporate the button feeding and orienting system may be accomplished in a highly simplified and economical manner. | 3 |
PRIORITY
[0001] This application claims priority under 35 USC 119 from Provisional Application Number 62/157,822 entitled “Frozen Tea Treat with Non-Synthetic Ingredients and Method of Making the Same”, filed May 6, 2015.
FIELD OF THE DISCLOSURE
[0002] The present disclosure relates to the field of frozen foods and associated treats using only non-synthetic and primarily non-processed foods and food additives. More specifically, the present disclosure relates to ice lollys composed primarily of tea with the addition of nutrients such as minerals and vitamins existing in powders, purees or liquid concentrates of fruits and/or vegetables which are combined and frozen, allowing for shelf stability and portability as well as a method for processing and packaging the same without the use of heat and/or pasteurization.
BACKGROUND
[0003] The statements in this section merely provide background information related to the present disclosure and are not provided to constitute prior art.
[0004] Iced lollys are a common type of frozen treat. The ice lolly, however, is not typically an option for health conscious consumers, as it is often prepared with ingredients that include processed and often unhealthy sugars and fats. Ice lollys are sold frozen, and therefore, are also subject to melting if not timely stored in the frozen state.
[0005] In addition, the ice lolly, while it may be soothing for the consumer, is often not nourishing. Often times, people undergoing medical procedures are patients unable to eat food or drink liquids normally either before or after undergoing a particular medical procedure. Nevertheless, patients need to remain hydrated and nourished. Patients may be given primarily sugar water with synthetic or even “natural” flavoring to provide hydration, but such ice lollys have little or no nutritional value components, and therefore do not provide the source of nourishment desired.
[0006] This and other issues are especially prevalent in today's North American culture and often the children of many North Americans are subjected to these improper frozen “treats” as an alternative to those which parents would rather provide. The compromise often occurs due to the need for convenience as well as the need for having a shelf stable product which can be acquired within a moments' notice. Health conscious consumers, as well as healthcare facilities (and their patients), now increasingly desire alternative delivery systems for vitamins and nutrient rich ingredients. Indeed, several consumer products exist on the market that infuse such nourishing aspects into their products that, by themselves have, little if any nutritional value, such as water and gum.
[0007] However, there are no primarily tea based iced products, composed of non-synthetic ingredients, that offer healthy tea based frozen ice lollys for convenience to health conscious consumers, and no such product for those undergoing medical procedures or otherwise struggling with health issues. The use of tea instead of (mostly pure) water as a primary base for these products is a critical part of the invention described herein. Regarded for thousands of years in Asian countries as a key to good health, happiness, and wisdom, tea has caught the attention of researchers in the West, who are continually discovering the many health benefits of different types of teas.
[0008] Studies have found that some teas may help with cancer, heart disease, and diabetes; encourage weight loss; lower cholesterol; and bring about mental alertness. Tea also is known to possess antimicrobial qualities.
[0009] The American Dietetic Association states that natural teas have less caffeine than coffee and it has been established that the compounds in tea—flavonoids—are good for the heart and may reduce the risk of certain cancers. Although a lot of questions remain about steeping for the most benefit or how much you need to drink, nutritionists agree that essentially any tea is healthful tea.
[0010] Tea is a name given to a lot of brews, but purists consider only green tea, black tea, white tea, oolong tea, and pu-erh (Pu'er) tea as actual teas. These tea leaves are all derived from the Camellia sinensis plant, a shrub native to China and India, and contains the unique antioxidants known as flavonoids. The most potent of these, known as ECGC, which is Epigallocatechin gallate (EGCG), also known as epigallocatechin-3-gallate, which is the ester of epigallocatechin and gallic acid, and is a type of catechin that helps quench free radicals that can contribute to cancer, heart disease, and clogged arteries. All these teas also contain caffeine and theanine, which positively affect the human brain and seem to heighten mental alertness.
[0011] The more processed the tea leaves, usually the lower the polyphenol content. These polyphenols include flavonoids. Oolong and black teas are more highly oxidized or fermented leading to lower concentrations of polyphenols than green tea.
[0012] As stated above, among all tea polyphenols, epigallocatechin-3-gallate has been shown to be responsible for much of the health promoting abilities of tea including anti-inflammatory, antimicrobial, anti-tumor, and anti-oxidative properties. The antibacterial, antiviral, and antifungal activities of different types of tea and their polyphenols allow for the composition of the present invention to be manufactured without the use of (often toxic) preservatives or antibacterial agents and to be processed while cold (preferably at or below 4 degrees centigrade) without the use of heating and/or pasteurization. There is a synergistic effect of tea polyphenols in combination with conventional antimicrobial agents that are effective against clinical multidrug-resistant microorganisms, which is another purpose for using teas as the basis for the compositions of the present invention. It has been found during the development of these compositions, and in contrast to what others have earlier realized and reported is that the existence of bacteria and inconsistency of the teas is inherent in the steeping process. For this and other reasons which will become apparent in the present disclosure, the frozen compositions do not employ tea processing using steeping. In some cases, the fruit and/or vegetables may be flash pasteurized prior to being used as an additive to the compositions of the present disclosure. The compositions described herein are mixtures.
[0013] The compositions (mixtures) herein have recently been developed with rooibos tea which in this case is added as a powder which initially was brewed (steeped) and then evaporated using spray drying techniques in order to not further reduce the natural inherent enzymatic activity and nature of the rooibos plant leaves. The powder is subsequently mixed with water and no solid residue is evident when this process takes place in providing the compositions of the present disclosure.
[0014] Health benefits of red rooibos tea include its use as a cure for nagging headaches, insomnia, asthma, eczema, bone weakness, hypertension, allergies, and premature aging. The tea is absolutely free from caffeine content and is also low in tannins. Drinking rooibos tea can further ease severe stomach cramps, as well as bring relief to asthma and other related conditions. It also boosts the immune system of the human body. Rooibos tea or red tea is a medicinal, herbal beverage that is acquired from the Aspalathus linearis bush plant that is found in South Africa. According to the South African Rooibos Council, rooibos is not a true tea, but an herb. The fermented tea is red in color. The rooibos plant grows naturally without any caffeine. This is important, as it means it does not need to undergo a chemical process to remove the caffeine. The other key benefit of no caffeine is that rooibos tea can be consumed in unrestricted amounts.
[0015] Rooibos tea also contains a wide array of antioxidants, which help to protect the body in a number of ways. Two polyphenol antioxidants known as aspalathin and nothofagin are found in high concentrations in rooibos tea. These antioxidants protect the immune system by quenching free radicals. These polyphenols also have anti-inflammatory properties and can safeguard against heart disease. Some studies have demonstrated a link between consumption of rooibos tea and a reduction of cancer-causing chemicals. This is because of the high level of dominant antioxidants, some of which have anti-mutagenic (anti-cancer) properties.
[0016] Another of the key health benefits of rooibos tea is that it contains several minerals that are vital to health. These include: magnesium (essential for the nervous system), calcium & manganese (essential for strong teeth and bones), zinc (important for metabolism) and iron (critical for helping blood & muscles distribute oxygen). One of the many potent antioxidants in rooibos tea is known as Chysoeriol. It can improve circulation by preventing the activity of the enzyme that triggers cardiovascular disease. Drinking of rooibos tea also has been known to lower blood pressure and cholesterol.
[0017] As rooibos tea contains high levels of flavonoids, one particular flavonoid known as quercetin has the ability to relieve numerous abdominal ailments such as cramps, diarrhea and indigestion. Flavonoids are known help to reduce spasm, inflammation and allergies. It has also been widely stated that the health benefits of rooibos tea extend to alleviating colic in babies—and as it is totally caffeine free, it is perfectly safe for them to drink rooibos tea.
[0018] Unlike most black teas, which prevent the body from absorbing iron effectively because of the tannins they contain, rooibos tea supports the body in absorbing iron. Rooibos tea contains less than half the tannins of black tea. A recent study found that rooibos tea contains phenylpyretic acid, which can help to improve acne, psoriasis and eczema. Drinking rooibos tea regularly can protect against a process known as lipid peridoxation. This occurs when free radicals damage brain cells and nerve tissue. If this is prolonged, it can lead eventually to progressive and deteriorating brain disease, such as Alzheimer's. Again, rooibos tea is unique in that it can be consumed often due to its lack of caffeine and is therefore known to help people to feel calm and relaxed. Together with the use of coconut palm ester(s) as the source for additional sweetening, the compositional mixtures of the present disclosure provide a frozen treat which is extremely nutritious, does not spike blood sugar levels, and does not provide caffeine so that it can be enjoyed at any time of the day or night without sleep deprivation issues. The “Dee Bees Frozen ice lolly” treats are the first certified Non-GMO, organic, kosher, vegan, tea-based treats that are gluten, dairy, nut, and soy free. These were developed to provide an option in place of high levels of sugar in frozen treats or other low-nutrient using other than whole food snacks.
SUMMARY
[0019] The present invention solves a need in the frozen food industry by mixing together a variety of ingredients in a tea based formulation to form frozen compositions.
[0020] In a one embodiment what is provided is a frozen liquid tea based composition comprising: water, non-genetically modified organism (non-GMO) grown tea powder or tea concentrate, methyl glucoside coconut oil ester, guar, gellan or pectin gum, and USDA certified organic non-genetically modified organism (non-GMO) grown fruit or vegetables in the form of a concentrate of liquid, puree, or powder.
[0021] In another embodiment, a method of forming a frozen liquid composition, wherein the composition is water, tea powder or tea concentrate, methyl glucoside coconut oil ester, guar, gellan or pectin gum, and USDA certified organic non-genetically modified organism (GMO) grown fruits or vegetables in the form of a concentrate of liquid, puree, or powder comprising the steps of:
mixing the ingredients of said composition into a homogeneous mixture within a mixing device kept at or below 4 degrees Centigrade thereby keeping said mixture at or below 4 degrees Centigrade while filling and mixing said mixture into a container; (ii) removing said mixture from said container after said mixture is homogeneous; (iii) filling a cavity with said mixture while maintaining said mixture at or below 4 degrees Centigrade; (iv) continuously cooling said mixture and; (v) freezing said mixture within said cavity.
[0027] Another advantage of the present invention is that it provides a healthful USDA certified organic, kosher, non-genetically modified (non-GMO) grown alternative to frozen treats that conventionally contain high levels of processed sugars, fruits, and vegetables which are processed with heat or pasteurization. The process also allows for convenient delivery to health conscious consumers. The use of cold processing (at or below 4 degrees Centigrade throughout the processing cycle) improves the enzymatic activity of any of the fruits and vegetable powders, purees, and liquid concentrates used when compared to that of heated processes. This processing technique also allows for manufacture of the compositions of the present disclosure without the need for preservatives or antimicrobial/antibacterial additives.
[0028] Another advantage is that it may be sold in distinct flavors and sold in a shelf-stable frozen liquid form.
[0029] The details of one or more embodiments of the invention are set forth in the accompanying drawings and description below. The list of advantages above is not intended to be exhaustive. Other objects, features, and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a product flow chart describing the process for manufacturing the tea based composition ice lollys according to one embodiment of the present invention.
DETAILED DESCRIPTION
[0031] The present invention relates to preparing liquid tea-based compositions for processing frozen ice lollys comprising certified USDA organic, kosher, non-GMO fruit and vegetable ingredients and apparatus for packaging the same. Further explanation and variations of the present invention are described below with reference to FIG. 1 .
[0032] FIG. 1 is a flowchart that describes the method of processing the tea-based ice lolly compositions of the present disclosure according to at least one embodiment of the present invention. To begin the process, perishable non-GMO, USDA certified organic, kosher ingredients are delivered ( 101 ) to the loading dock and stored at or below 4 degrees Centigrade in a refrigerated container ( 102 ). Also received ( 103 ) are dry organic non-GMO ingredients that are stored in an air-conditioned warehouse ( 104 ). Further, organic flavors and colors (if any) are also received at the loading dock ( 105 ) and stored in the same warehouse ( 104 ) as the dry ingredients. Next ( 107 ), the necessary and required amounts of cold powdered tea is measured and prepared by mixing in purified preconditioned water which can be accomplished by any one of a number of conventional means including reverse osmosis, distillation, deionization, filtration, etc. for adding to the mixing tank ( 107 , 108 , and 109 ). Also subsequently measured and added in the necessary and required amounts are the fruit (and/or vegetables), ( 108 ) as well as a stabilizer such as the organic guar gum into the mixing tank once the tea has reached homogeneous conditions. In this case, homogeneity is measured by the absence of any remaining solids or particles measured or seen visibly. This ensures the tea is providing its full set of attributes and properties as described in detail above. Finally, the ingredients are blended with or without the sweetener(s), specifically coconut palm nectar (coconut sugar), in the mixing tank ( 107 , 108 , 109 ) and mixed for the appropriate time at or below 4 degrees Centigrade. For emphasis, the entire process is performed at or below 4 degrees Centigrade prior to freezing to ensure non bacterial contamination of the composition before, during and after mixing. The preferred sweetener of choice is known by its latin name “cocos nucifer” which is certified organic tree sap that has been prepared by taking the sap of the coconut tree inflorescence (coconut fruits are not used for the manufacturing of this product) and the sap is evaporated until it turns into fine granules. The nutritional analysis of this sweetener which is manufactured and distributed through Sunopta which can be found at the following internet website address: www. sunopta.com and tradinorganic, which can be found at the following internet website address, www.tradinorganic.com, is as follows:
[0000]
Fructose
<0.25%
Glucose
<0.25%
Lactose
<0.25%
Maltose
<0.25%
Sucrose
93.16%
Total sugars
93.82%
Ash
2.265%
Calcium
0.472 mg/100 g
Carbohydrates
94.72%
Iron
1.2 mg/100 g
Moisture
1.18%
Protein
1.42%
Sodium
7.17 mg/100 g
Total Dietary Fiber
0.9%
Total Fat
0.424%
Vitamin A (Beta Carotene)
<100 IU/100 g
Vitamin C
<0.5 mg/100 g
Calories
388 cal/100 g
[0033] Once mixing is complete, a valve on the mixing tank ( 107 , 108 , 109 ) is opened and the mixed slurry is dispensed into the in-line molding equipment, such as a “Vita-line” ( 110 ) from Gram Equipment, Inc., New Jersey, and the freezing process is begun. At this step in the process, the mold cavity and accessories ( 111 , 112 ) which are received and stored in warehouse are sent to the end of the Vita-line ( 110 ) for filling so that freezing can occur in the proper mold cavities prior to final packaging and labeling. Wrapping and boxing ( 113 ) is performed next, followed by a quality control section utilizing a “safeline” metal detector ( 114 ), such as those manufactured by Mettler-Toledo, to ensure no foreign metal objects are trapped in the final packaged products.
[0034] Subsequent to full quality inspection, the ice lollys are packed into master cases ( 115 ), which must be dated and coded and sealed ( 116 ). The cases are then palletized and labeled as “organic” ( 117 ) prior to being placed in a deep freezer ( 118 ) set for or below −23 degrees Centigrade. Ice lollys are then shipped ( 119 ) by truck, rail or air to the appropriate distribution wholesale or retail facilities.
[0035] The present invention preferably comes in at least nine flavor compositions, including; Berries 'N Cherries, Dark Chocolate Mint, Mango, Southern Ice Tea, and Toasted Coconut. Each flavored composition comprises a unique tea based ingredient profile and is formulated with a variety of the fruits and/or vegetables which must also be USDA certified organic, non-GMO and kosher graded.
[0036] Tables 1-9 below indicate an exemplary ingredient profile, formulation, and nutritional facts panel for each of the aforementioned and additional flavors according to at least one embodiment of the present invention:
[0000]
TABLE 1
Berries N′ Cherries
Ingredients
%
kg
Filtered water, (Liters = kg at room
60.0855%
2693.398
temperature)
FTO Rooibos Tea Extract Powder
0.0783%
3.509
FTO White Tea Distillate
0.2642%
11.843
Organic Vanilla Extract 2 fold
0.1957%
8.772
Organic Cherry Juice Concentrate 68 BRIX
7.1135%
318.871
Organic Strawberry Puree
14.5662%
652.947
Organic Blueberry Juice Concentrate,
1.5438%
69.204
65°Brix, frozen
Organic Blueberry Puree
6.5708%
294.542
Organic Guar Gum 6068
0.1566%
7.018
Organic Dehydrated Coconut Flower
9.4255%
422.509
Blossom Nectar
TOTAL
100.0000%
4482.612
NUTRITION INFORMATION
Nutrition Facts
Serving Size 1 bar (52 g)
Servings Per Container
Amount per Serving
Calories 30
Calories from Fat 0
% Daily Value*
Total Fat 0 g
0%
Saturated Fat 0 g
0%
Trans Fat 0 g
Cholesterol 0 mg
0%
Sodium 0 mg
0%
Total Carbohydrates
2%
7 g
Dietary Fiber 0 g
0%
Sugars 6 g
Protein 0 g
Vitamin A 0%*
Vitamin C 4%
Calcium 0%*
Iron 2%
*Percent Daily Values are based on a 2,000 calorie diet. Your Daily
Values may be higher or lower depending on your calorie needs.
Calories:
2,000
2,500
Total Fat
Less than 65
g
80 g
Sat Fat
Less than 20
g
25 g
Cholesterol
Less than 300
mg
300 mg
Sodium
Less than 2,400
mg
2,400 mg
Total Carb
300
g
375 g
Dietary Fiber
25
g
30 g
[0000]
TABLE 2
Tropical Mango
Ingredients
%
kg
Filtered water, (Liters/kg at room temperature)
66.470%
2979.586
FTO Rooibos Tea Extract Powder
0.206%
9.216
Organic Vanilla Extract 2 fold
0.3855%
17.280
Organic Mango Puree
20.0082%
896.889
Organic Pineapple Juice Concentrate
2.6535%
118.947
Organic Guar Gum 6068 (Food Specialties)
0.2079%
9.320
Organic Dehydrated Coconut Flower Blossom
10.0181%
449.072
Nectar
Organic Citric Acid
0.0514%
2.304
TOTAL
100.000%
4482.615
NUTRITION INFORMATION
Nutrition Facts
Serving Size 1 bar (52 g)
Servings Per Container
Amount per Serving
Calories 25
Calories from Fat 0
% Daily Value*
Total Fat 0 g
0%
Saturated Fat 0 g
0%
Trans Fat 0 g
Cholesterol 0 mg
0%
Sodium 0 mg
0%
Total Carbohydrates
2%
7 g
Dietary Fiber 0 g
0%
Sugars 6 g
Protein 0 g
Vitamin A 8%*
Vitamin C 6%
Calcium 0%*
Iron 0%
*Percent Daily Values are based on a 2,000 calorie diet. Your Daily
Values may be higher or lower depending on your calorie needs.
Calories:
2,000
2,500
Total Fat
Less than 65
g
80 g
Sat Fat
Less than 20
g
25 g
Cholesterol
Less than 300
mg
300 mg
Sodium
Less than 2,400
mg
2,400 mg
Total
300
g
375 g
Carbohydrate
Dietary Fiber
25
g
30 g
[0000]
TABLE 3
Southern Iced Tea
Ingredients
%
kg
Filtered water, (Liters/kg at room temperature)
47.881%
2146.325
Organic Black Tea Concentrate
40.106%
1797.796
Organic Guar Gum
0.2980%
13.358
Organic Lemon Juice, Concentrate
0.2119%
9.497
Organic Lemon Essence (primal essence)
0.0092%
0.412
Organic Liquid Honey
11.4943%
515.243
TOTAL
100.000%
4482.631
NUTRITION INFORMATION
Nutrition Facts
Serving Size 1 bar (52 g)
Servings Per Container
Amount per Serving
Calories 20
Calories from Fat 0
% Daily Value*
Total Fat 0 g
0%
Saturated Fat 0 g
0%
Trans Fat 0 g
Cholesterol 0 mg
0%
Sodium 0 mg
0%
Total Carbohydrates 5 g
2%
Dietary Fiber 0 g
0%
Sugars 5 g
Protein 0 g
Vitamin A 0%*
Vitamin C 0%
Calcium 0%*
Iron 0%
*Percent Daily Values are based on a 2,000 calorie diet. Your Daily
Values may be higher or lower depending on your calorie needs.
Calories:
2,000
2,500
Total Fat
Less than 65
g
80 g
Sat Fat
Less than 20
g
25 g
Cholesterol
Less than 300
mg
300 mg
Sodium
Less than 2,400
mg
2,400 mg
Total
300-325 g
Carbohydrate
Dietary Fiber
25-30 g
[0000]
TABLE 4
Toasted Coconut
Ingredients
%
kg
Filtered water, (Liters/kg at room temperature)
48.781%
2186.644
Rooibos Tea Extract Powder
0.1005%
4.507
Organic Coconut Cream
39.1059%
1752.965
Organic Guar Gum 6068
0.2980%
13.358
Organic Dehydrated Coconut Flower Blossom
11.4943%
515.243
Nectar
Organic Pineapple Juice Concentrate
0.2209%
9.900
TOTAL
100.000%
4482.617
NUTRITION INFORMATION
Nutrition Facts
Serving Size 1 bar (52 g)
Servings Per Container
Amount per Serving
Calories 70
Calories from Fat
40
% Daily Value*
Total Fat 5 g
8%
Saturated Fat 5 g
25%
Trans Fat 0 g
Cholesterol 0 mg
0%
Sodium 25 mg
1%
Total Carbohydrates
2%
7 g
Dietary Fiber 0 g
0%
Sugars 6 g
Protein 0 g
Vitamin A 0%*
Vitamin C 2%
Calcium 0%*
Iron 2%
*Percent Daily Values are based on a 2,000 calorie diet. Your Daily
Values may be higher or lower depending on your calorie needs.
Calories:
2,000
2,500
Total Fat
Less than 65
g
80 g
Sat Fat
Less than 20
g
25 g
Cholesterol
Less than 300
mg
300 mg
Sodium
Less than 2,400
mg
2,400 mg
Total
300
g
375 g
Carbohydrate
Dietary Fiber
25
g
30 g
[0000]
TABLE 5
Dark Chocolate Mint
Ingredients
%
kg
Filtered water, (Liters/kg at room temperature)
88.620%
1986.246
Rooibos Tea Extract Powder
0.185%
4.147
Organic Peppermint Tea Essence
0.0496%
1.111
Organic Dehydrated Coconut Flower Blossom
10.3675%
232.367
Nectar
Organic Vanilla Extract 2 fold
0.0835%
1.871
Organic Guar Gum 6068
0.2949%
6.609
Organic Cocoa Distillate
0.4000%
8.965
TOTAL
100.000%
2241.3161
[0000]
TABLE 6
Raspberry Chamomile Cream
Ingredients
%
kg
Filtered water, (Liters/kg at room temperature)
68.948%
7.317
Chamomile Essence (Primal Essence)
0.101%
0.011
Raspberry Juice concentrate
1.0157%
0.108
Organic Vanilla Extract 2 fold
0.1889%
0.020
Organic Coconut Cream ITI TROPICALS
16.2214%
1.721
Organic Guar Gum 6068 (Food Specialties)
0.2199%
0.023
Organic Dehydrated Coconut Flower Blossom
9.4439%
1.002
Nectar
Organic Coconut Water Powder
1.663%
0.176
Raspberry Puree
2.1986%
0.233
TOTAL
100.000%
10.612
[0000]
TABLE 7
Hibiscus Lemonade
Ingredients
%
kg
Filtered water, (Liters/kg at room temperature)
84.701%
8.995
HIBISCUS CONCENTRATE
1.166%
0.117
Organic Guar Gum
0.2980%
0.032
Organic Lemon Juice, Concentrate
0.3119%
0.033
Organic Lemon Essence (primal essence)
0.0292%
0.003
Organic Liquid Honey
13.4943%
1.432
TOTAL
100.000%
10.612
[0000]
TABLE 8
Raspberry Citrus Green Tea
Ingredients
%
Filtered water, (Liters/kg at room temperature)
57.730%
Organic Raspberry Puree
29.1059%
Organic Dehydrated Coconut Flower Blossom Nectar
12.4943%
Organic Guar Gum
0.2980%
Organic Lemon Juice, Concentrate
0.2209%
FTO Green Tea Concentrate
0.1005%
Organic Lemon Extract (primal essence)
0.0505%
TOTAL
100.000%
NUTRITION INFORMATION
Nutrition Facts
Serving Size 1 bar (52 g)
Servings Per Container
Amount per Serving
Calories 30
Calories from Fat 0
% Daily Value*
Total Fat 0 g
0%
Saturated Fat 0 g
0%
Trans Fat 0 g
Cholesterol 0 mg
0%
Sodium 4 mg
0%
Total Carbohydrates 8 g
3%
Dietary Fiber less than 1 gram
0%
Sugars 7 g
Protein 0 g
Vitamin A 0%*
Vitamin C 4%
Calcium 0%*
Iron 2%
*Percent Daily Values are based on a 2,000 calorie diet. Your Daily
Values may be higher or lower depending on your calorie needs.
Calories:
2,000
2,500
Total Fat
Less than 65
g
80 g
Sat Fat
Less than 20
g
25 g
Cholesterol
Less than 300
mg
300 mg
Sodium
Less than 2,400
mg
2,400 mg
Total
300
g
375 g
Carbohydrate
Dietary Fiber
25
g
30 g
[0000]
TABLE 9
Raspberry Coconut Tea
Ingredients
%
Filtered water, (Litres/kg at room temperature)
46.281%
FTO Hibiscus Extract
0.5005%
Organic Coconut Cream
29.1059%
Organic Guar Gum
0.2980%
Organic Dehydrated Coconut Flower Blossom Nectar
11.4943%
Chamomile Extract
0.100%
Raspberry Puree
12.2209%
TOTAL
100.000%
Nutrition Facts
Serving Size 1 bar (52 g)
Servings Per Container 1
Amount per Serving
Calories 40
Calories from Fat 20
% Daily Value*
Total Fat 2 g
3%
Saturated Fat 0 g
0%
Trans Fat 0 g
Cholesterol 0 mg
0%
Sodium 10 mg
0%
Total Carbohydrates 6 g
2%
Dietary Fiber 0 g
0%
Sugars 6 g
Protein 0 g
Vitamin A 0%*
Vitamin C 2%
Calcium 0%*
Iron 2%
*Percent Daily Values are based on a 2,000 calorie diet. Your Daily
Values may be higher or lower depending on your calorie needs.
Calories:
2,000
2,500
Total Fat
Less than 65
g
80 g
Sat Fat
Less than 20
g
25 g
Cholesterol
Less than 300
mg
300 mg
Sodium
Less than 2,400
mg
2,400 mg
Total Carbohydrate
300
g
375 g
Dietary Fiber
25
g
30 g
[0037] In a preferred embodiment, the final equilibrium pH of the at least nine flavors will not be greater than 7.00. Given the formulations and maximum equilibrium pH, each formulation is processed at or below 4 degrees Centigrade within 10 minutes or equivalent.
[0038] The packaging preserves product integrity from factory to shelf, allowing the product to be sold shelf stable and delivered as a freeze and eat product, thereby providing convenience to the consumer. The packaging is also bisphenol A (BPA) free.
[0039] A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are contemplated within the scope of the following claims. | The invention relates to ice lollys comprising a frozen liquid tea based composition comprising: water, tea powder or tea concentrate, methyl glucoside coconut oil ester, guar, gellan or pectin gum, and USDA certified organic non-genetically modified organism (non-GMO) grown fruit or vegetables in the form of a concentrate of liquid, puree, or powder. The processing and subsequent packaging allows the composition to be processed without heating and/or pasteurization but remain shelf stable in the frozen form. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 11/484,424, filed on Jul. 11, 2006, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the treatment of fluid acting waste for transport and disposal and more specifically to the stabilization of slurries and sludges.
BACKGROUND OF THE INVENTION
[0003] High solids content waste streams often contain enough water or other fluid to behave like a sludge or slurry. In this state, the waste is difficult to store, transport and dispose of. By way of example, oil and gas well drilling wastes can have a high proportion of solids in the form of cuttings generated as the bit penetrates the ground. The cuttings are returned to the surface by the flow of drilling fluid, usually referred to as the drilling mud, which is a viscous multi-phase fluid pumped down the well through the drill pipe. The mud exits through the bit and then returns to the surface in the annulus between the drill pipe and the wall of the bore being drilled, carrying the cuttings with it. When drilling is complete, both the mud and the cuttings need to be disposed of, and are together known as drilling waste. To facilitate economic and environmentally safe disposals, it is usually preferable to separate the mud (mostly liquids) and the cuttings (mostly solids) prior to disposal.
[0004] Through variations in local geology and the method of drilling, the cuttings from a single well can vary in size from coarse chips to very fine clay sized particles. When the particle size of the cuttings becomes very fine, there is less distinction between the mud and cuttings that are in suspension. Often the very fine suspended cuttings will not readily settle out or separate from the mud, which may reduce the usefulness of the mud for drilling purposes, and complicate the disposal process. There are several commonly used methods to separate drill cuttings from drilling mud. Often several of these methods are used concurrently during the drilling of the well.
[0005] The first common method of separating the cuttings from drilling mud is a vibrating shaker box, which has screens of various sizes to separate the coarse cuttings from the flowing mud. The mud gets reused and the cuttings are collected for disposal.
[0006] A second method to separate cuttings from drilling mud is through the use of settling tanks or a settling pond, called a sump. This method allows fine cuttings that went through the shaker screens to slowly settle to the bottom. The mud is removed from the top of the tank or sump and reused. A variation of the settling method is called flocculation. Through chemical changes to the mud, very fine cuttings particles cling together to make larger particles, which settle faster.
[0007] A third method of separating cuttings from drilling mud is through the use of centrifuge. Usually centrifuging is combined with chemical flocculation of the mud, and will rapidly strip most of the very fine cuttings from the mud. The mud is reused and the very fine cuttings are usually left in the form of a thick heavy sludge.
[0008] After the drill cuttings (mostly solids) are separated from the drilling mud (mostly liquids) by the methods described above, the drill cuttings will normally be defined as a solid based on EPA method 9095A, also known as the paint filter test. However, the common methods of separating solid cuttings from drilling mud described above are not 100% effective. There is always a small amount of fluid in the interstitial pore spaces of the drill cuttings that is not economically viable to remove. It is during the process of storing or transporting these cuttings, that this small amount of fluid becomes problematic.
[0009] In the case of coarse drill cuttings, liquids can be forced out of the interstitial pore spaces as the cuttings settle through time, or by the shaking and vibration during long distance transport. The finer drill cuttings in the form of a thick sludge or slurry will often change to flow like a liquid if transported, spilled, or agitated in any way, much like quick sand. This makes the storage, handling and transportation of this drilling waste to approved facilities, difficult, dangerous and expensive. Drilling waste is just one example of waste streams that, although technically a solid, can behave in this manner. Such streams will sometimes be referred to as fluidic wastes, meaning solid wastes that under certain conditions will behave like a fluid
[0010] The solid drill cuttings must therefore be stabilized by solidification prior to safe storage, transport and disposal.
[0011] Sludge stabilization and solidification techniques are known in the art and reference is made in this regard to U.S. Pat. Nos. 4,113,504, 4,913,585, 5,916,122 and 6,322,489. Some of these technologies however are not suitable for waste streams intended to be handled by conventional loaders and trucks, for example because they involve actual cementitious solidification to prevent leaching of heavy metals (U.S. Pat. No. 4,113,504). U.S. Pat. No. 6,322,489 teaches a method of encapsulation that will render the waste sufficiently safe for disposal in wetlands. Encapsulation at this level of safety is not realistically or economically sustainable on an industry wide basis.
[0012] More practically, drilling wastes are stabilized with wood fiber waste which itself is a waste stream from the pulp and paper and lumber industries. There is now however sufficient demand for wood waste that the industry is charging for the product. The use of wood waste also requires specialized trucks to transport treated waste, all of which makes the use of wood waste increasingly expensive.
[0013] There are other disadvantages to the use of wood waste as a stabilization agent. Its moisture content fluctuates with the seasons and/or its exposure to the elements, affecting its absorption rate. Particle size, density and consistency are also subject to considerable and unpredictable fluctuation.
[0014] Moreover, it is not a particularly good absorbent. It is common to add 30 to 50% wood fibre (by weight) to the drilling waste for adequate stabilization. Use of these amounts can be effective, but the result is an additional 30 to 50% of added waste tonnage for transport. In addition to adding tonnage, the wood waste can reduce the specific gravity of the stabilized waste to as little as 0.7 to 1.2, which substantially reduces the efficiency of transporting the material by truck. The trucks become full long before reaching their maximum weight capacity. To compensate for the light loads, truck operators will charge by the trip instead of by tonnage. Therefore costs will be higher in view of the greater number of loads required, operator hours, fuel consumed and tippage at a landfill.
SUMMARY OF THE INVENTION
[0015] The applicant has found that the use of a mineral absorbent and/or a mineral adsorbent, or blends thereof, when mixed with drilling wastes, produces a stable and easy to handle mixture that can be loaded and handled using conventional dirt moving equipment such as shovels, loaders and dump trucks. These additives also provide structure to the mixed waste, which can therefore be advantageously stored in a stable pile while awaiting transport for disposal. Unmixed slurries and sludges simply slough and spread if piled.
[0016] To facilitate the following description of the invention, the word “absorbent” is meant to include one or both of an actual absorbent, which is penetrated by the substance being absorbed, or an adsorbent, which retains that substance on its surface, unless the context indicates to the contrary. The purpose of the absorbent/adsorbent is essentially the same and that is to take up the liquid fraction so that the remaining waste behaves more like a stable solid.
[0017] The use of mineral absorbents produces a consistently dry product. The applicants have found that the required amount to stabilize sludgy drilling waste is from about 1.5% to about 10% and advantageously 2% to 3% by weight of the drilling waste. This is subject to factors such as the nature of the waste stream, the equipment used to drill the well, particle size, the solids control equipment used on the well, the mud system used in the well and other variables normally associated with the drilling of a bore hole. It is expected that in some applications, the amount of stabilizer required may be more or less than this range, but test results to date indicate that about 2% to 10% provides commercial utility.
[0018] The use of so little absorbent means that the specific gravity of the waste is reduced only slightly so that trucking becomes far more efficient. Based on studies performed by the applicant using historical data, wells that normally produce 700 tonnes of drilling waste after treatment with wood fiber produce 400 or fewer tonnes of drilling waste using the applicant's mineral adsorbents/absorbents or blends thereof. This represents a significant 300 fewer tonnes to transport and dispose of. Disposal costs at a landfill (tipping) are typically $25.00 to $40.00 per tonne. Haulage per tonne is considerably more expensive than the tipping. Haulage per tonne can become exorbitant when extremely long hauling distances are involved. For example, in environmentally sensitive areas such as the Arctic, there are typically no close disposal facilities. Therefore, the economic benefits of this invention can be considerable compared to the current industry standard of wood fibre.
[0019] Accordingly, it is an object of the present invention to provide a method of stabilizing drilling waste streams that obviates and mitigates the disadvantages of the prior art.
[0020] According to the present invention, there is provided a method of treating waste having both liquid and solid fractions, the method comprising adding to said waste a mineral absorbent in an amount from about 1.5 to 10 weight per cent of said waste.
[0021] According to another aspect of the present invention, there is provided a method of stabilizing a fluidic waste having both liquid and solid fractions therein, the method comprising mixing said fluidic waste with a mineral absorbent and/or adsorbent in an amount from about 1.5 to 10 weight percent of said fluidic waste.
[0022] According to yet another aspect of the present invention, there is also provided a method of drying drilling waste having both liquid and solid fractions that is in the form of a sludge or slurry, the method comprising adding a mineral absorbent to said waste and blending said waste and said absorbent together for a predetermined amount of time until said waste behaves like a solid.
[0023] According to yet a further aspect of the present invention, there is also provided a method of solidifying a fluid acting waste which includes a major solids fraction and a minor fluids fraction, the method comprising blending said waste with a mineral additive that absorbs and/or adsorbs some or all of said fluid fraction, said mineral additive being present in an amount from about 1.5 to 10 weight percent of said waste.
[0024] According to yet a further aspect of the present invention, there is also provided a method of drying and solidifying a waste in the form of a sludge or slurry, the method comprising mixing said sludge or slurry with at least one mineral additive adapted to adsorb and/or adsorb some or all of liquid in said sludge or slurry, said mixing continuing until said sludge or slurry and said mineral additive are thoroughly blended whereby said sludge or slurry becomes stackable without sloughing, said mineral additive being added to said sludge or slurry in an amount from about 1.5 to 10 weight percent of said sludge or slurry.
[0025] According to yet another aspect of the present invention, there is also provided a mineral additive for the stabilization of fluid acting waste which have both a solid and liquid fraction, said additive comprising a blend of vermiculite and one or both of perlite and zeolite.
[0026] According to yet another aspect of the present invention, there is provided a method of treating waste comprising both liquid and solid fractions for disposal by adding to said waste a mineral absorbent in an amount of from about 2 to 10 weight per cent of said drilling waste.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] The following description is provided with reference to the stabilization of drilling waste from the drilling of oil and gas wells. This use is intended however to be exemplary only, and the present invention will be equally useful with respect to other wastes comprising both liquid and solid fractions that can behave like a fluid. As used herein, stabilization is intended to include one or both of drying and solidification, with solidification meaning that the treated waste acts or has the characteristics of a substantially dry particulate.
[0028] In accordance with a preferred aspect of the present invention, drilling waste is stabilized by the addition of a mineral absorbent and/or adsorbent. The mineral absorbent is advantageously expanded vermiculite having a particle size in the range of a 5 mesh sieve to a 200 mesh sieve and a specific gravity of 0.1 g/cm 3 to 0.2 g/cm 3 . Vermiculite is available from suppliers such as Grace Construction Products for commercial/industrial use. Vermiculite is also widely available at a retail level at numerous hardware, and home and garden establishments.
[0029] Depending upon the desired characteristics of the mixed waste, the vermiculite can be blended with other mineral components including perlite and zeolite. The perlite typically has a particle size in the range of a five mesh sieve to a 200 mesh sieve and a density of 0.10 g/cm 3 to 0.30 g/cm 3 . The zeolite particles typically range in size from a 10 mesh sieve to a 200 mesh sieve and have a density of 0.80 g/cm 3 to 1.20 g/cm 3 .
[0030] The ratio of vermiculite to these additives is not critical and will vary depending upon the desired characteristics of the mixed drilling waste. In a typical application however, the respective weight ratios of vermiculite, perlite fines, and zeolite would be 5:3:2. That is, for every 10 parts by weight of the mineral blend, 5 parts by weight would be vermiculite,. 3 parts by weight would be perlite fines, and 2 parts by weight would be zeolite. This can also be expressed as a volume ratio, or using other proportions.
[0031] The exact ratio of vermiculite to perlite and/or zeolite will vary with empirical observation and experience in any particular area. Drilling equipment, the mud system, solids control equipment, local geology, and weather conditions are common variables that would affect the final blend. Nevertheless, based on testing to date, the ratios described above have proven effective over a broad range of variables.
[0032] Each additive to the blend has various advantages and disadvantages that can be adjusted to suit changing needs. For example, both zeolite and perlite are good adsorbents. Although zeolite is heavier and more expensive than fine perlite, it is most effective to stabilize sludgy drilling waste, and make it stackable. If the drilling waste is less sludgy, a higher percentage of perlite could be used, which has the advantage of being less expensive, and lighter than zeolite.
[0033] The vermiculite and other principal additives described above can themselves be blended with other optional additives including but not limited to sand, cement, lime, coal dust and granular activated charcoal to obtain complementary characteristics or reactions. For example, sand can be used for traction if the vermiculite mixture is used as an absorbent where slippery floors are a concern. The addition of lime to the vermiculite mixture can be used to change the SAR (sodium adsorbsion ratio) of the drill cuttings as a form of waste treatment in some situations.
[0034] The present stabilizing absorbent product is pre-blended, bagged and stored prior to use. It can then be transported by truck to the well site and off loaded using existing equipment. In one application contemplated by the applicant, the stabilizing absorbent is transported in 54 cubic foot totes and is then simply dumped onto the drilling waste using for example an on site loader of one is available. The loader can mix the drilling waste with the stabilizing absorbent until a uniform mixture is achieved.
[0035] During mixing process, any interstitial fluid in the drilling waste is absorbed and/or adsorbed by the stabilizer. The size of the drill cuttings in the drilling waste can be reduced by the action of the mixing and the abrasive properties of the stabilizing blend. The reduced size of the drill cuttings increases the overall surface area of the stabilized drilling waste particles relative to its volume, which improves the absorption of fluids. Better blending could be achieved using a pug mill or paddle mixer, but use of the on-site loader is effective and obviously more economic because its already on the site and has its own operator. Once the blended drilling waste is no longer a sludge or slurry, it can be piled without sloughing while awaiting transport. The mixed waste will be sufficiently dry that ordinary dump trucks can be used for transportation.
EXAMPLE 1
[0036] A series of eight similar wells were drilled in North Eastern British Columbia, Canada south of Ft. St. John by an oil and gas operator. All eight wells were drilled with an oil based mud system and the drilling waste generated was tested and then stabilized on the fly with either conventional wood fiber or the mineral absorbent of the present invention, using the loader to mix the stabilizer with the waste. The waste was then contained and batch hauled to a Class 2 landfill for disposal.
[0037] The first six wells had the following amounts of waste stabilized with wood fibre dumped at the Class 2 landfill: 820.72, 652.05, 610.25, 936.91, 582.75, 1109.04 metric tonnes respectively, for an average of 785.28 metric tonnes per well. It was not documented how much wood fiber was utilized for stabilization.
[0038] The drilling waste from two wells was handled in the same manner, however, the mineral absorbent of the present invention were used instead of wood fiber for stabilization. This commenced on Jul. 28, 2004 and finished on Sep. 23, 2004. A total of 349.54 and 441.20 metric tonnes were hauled. Mineral absorbent use was 7600 Kg's (2.22% wt./wt.) and 8745 Kg's (2.02% wt./wt.) respectively. This was an average of 395.37 metric tonnes per well hauled to the Class 2 landfill.
[0039] All weights were scaled at the Class 2 landfill.
EXAMPLE 2
[0040] A well was drilled by an oil and gas operator near the town of Rocky Mountain House, Alberta, Canada in township 042, range 12, west of the 5 th meridian. The invert section of the hole began on Apr. 18, 2005 and finished drilling on May 31, 2005. The length of the invert section was 2610 meters with a bit size of 222 mm.
[0041] The solid drilling waste from this operation was stored in large horizontal storage tanks on location. After drilling there were five tanks that held a measured 340 m 3 of solid drilling waste.
[0042] Applicant's personal arrived on site May 27, 2005 to begin stabilization of the waste with the mineral absorbent of the present invention. A Hitachi excavator was used to perform the mixing and any free fluids that may have been encountered were removed with a vacuum unit to ensure regulatory compliance.
[0043] A total of 559.82 metric tonnes of material (both solids drilling waste plus the mineral absorbent used) was removed from the tanks and deposited into a Class 2 landfill for disposal. This weight was verified from the Class 2 landfill facility as each dump truck was weighed in and weighed out.
[0044] A total of 10.800 Kg of mineral absorbent in accordance with the present invention was used during the stabilization. This equates to 549.020 Kg of waste with the addition of 1.97% wt./wt. of mineral absorbent.
[0045] The above-described embodiments of the present invention are meant to be illustrative of preferred embodiments and are not intended to limit the scope of the present invention. Various modifications, which would be readily apparent to one skilled in the art, are intended to be within the scope of the present invention. The only limitations to the scope of the present invention are set forth in the following claims appended hereto. | There is described a method of treating a waste having both liquid and solid fractions, the method consisting of adding to the waste a mineral absorbent in an amount from about 1.5 to 10 weight percent of the waste. | 1 |
The present invention relates to an improved method for determining the smoke point of hydrocarbons, comprising in particular the acquisition and analysis of digital images, and a device for implementing such a method.
BACKGROUND OF THE INVENTION
The smoke point of a hydrocarbon is a characteristic that is routinely determined in the laboratories of refineries, mainly on kerosenes, aviation fuels and even lamp oils.
This characteristic is an important parameter since it is directly linked to the hydrocarbon composition of the fuels under test. In practice, the greater the C/H ratio, and therefore the lower the aromatic compound content, the higher the smoke point becomes and the better the fuel behaves on its combustion. In other words, the smoke point is quantitatively linked to the potential transfer of radiative heat and, in as much as this heat transfer exerts a strong influence on the temperature of the metallic parts, the smoke point therefore becomes a predictive indicator of the longevity of said metallic parts.
The smoke point does, unfortunately, however have the drawback of being fairly difficult to measure. Normally, for this, an analysis method is used that is the subject of a standardization (such as the method described in the ASTM D 1322 standard and its equivalents, such as ISO 3014, IP 57 and NF M 07-028) to enable the detection, then the measurement of the maximum height of a flame (normally expressed in mm and accurate to the nearest tenth of an mm) which can be obtained from the hydrocarbon under test without the formation of smoke.
In such a measurement, the sample is burned in a wick lamp, also described in the ASTM D 1322 standard, and the operator varies the position of the burner so as to gradually modify the height and the appearance of the flame, which changes slowly from a relatively elongated and jumpy state with a top end giving off a light smoke, to a state in which the flame height is shorter, with a top end that is perfectly rounded. Between these two flame states, the operator must also distinguish two other intermediate shapes, namely that having an elongated point, the edges of which appear concave in the top part and the one in which the pointed end has just disappeared and which forms a flame that is slightly rounded without smoke. It is when the flame has this last appearance that the operator records the height of the flame, on a scale graduated in mm positioned inside and at the back of the lamp. The final value of the smoke point retained for the sample under analysis is the average of three successive measurements, calculated to the nearest 0.1 mm.
The method of measuring the smoke point, as defined in the ASTM D 1322 standard, like all the analysis methods of this type, does, however, have limitations in terms of accuracy, mainly due to the assessment difficulties of the operator, in particular when taking the decision to judge the correct appearance of the flame, according to the standard, and also at the moment when the height of this flame is measured visually on the graduated scale. In practice, the good quality of the measurement of this height requires particular procedural precautions, the application of which depends entirely on the operator. Thus, the repeatability and reproducibility of the standardized test are respectively 2 mm and 3 mm.
The Applicant has proposed to remedy this difficulty by replacing the eye and the brain of the operator with a technical system or acquiring digital images mainly comprising a digital camera, or an equivalent of such a digital camera, and an associated computer system for analyzing and processing the stored digital images. However, the distinguishing of the different characteristic shapes of the flame, between the relatively elongated and jumpy state with a top end giving off a light smoke and the state presenting a shorter flame height with a top end that is perfectly rounded, is subjective and is ill-suited to the normal use of a computer program for analyzing and processing digital images. The Applicant, after much research work, has found that, surprisingly, the use of such a system associated with a choice of appropriate parameters and a correct calibration, would make it possible to spectacularly increase the accuracy of the method and obtain the smoke point of the hydrocarbon under test but without the problem of the subjectivity of the operator.
SUMMARY OF THE INVENTION
The subject of the invention is, consequently, a method for determining the smoke point of a hydrocarbon, comprising among the different steps defined in the ASTM D 1322 standard or its equivalents, the identification, among different appearances of the flame according to the position of the burner in the lamp, of a particular appearance of the flame and the reading of the height of this flame on a scale graduated in mm, characterized in that a series of digital images of the flame is taken and stored using a digital camera or an equivalent of such a camera, at intervals that are sufficiently close to enable, by analyzing these digital images, the detection of a sudden change in the shape of the flame, and that the height of said flame is measured at the moment of this sudden change in its shape, said height being considered as the smoke point of the hydrocarbon under test.
Preferably, the digital camera will be equipped with a photodetecting charge-coupled device (CCD). The image-taking intervals will preferably be between 0.1 and 2.0 seconds, and in particular between 0.5 and 1.0 second. The number of digital images of each series of images is preferably at least equal to 10.
The digital image-taking operations and the analysis and processing of these images to identify the image corresponding to the first sudden change in the shape of the flame are preferably automated using a dedicated software package.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts the trend of the Feret diameter according to the lowering of the position of the burner during the step (h) of the method of the present invention; and
FIG. 2 represents the value of the gray levels of a line of pixels passing mid-height through the flame, perpendicular to the vertical axis of symmetry of the flame.
DETAILED DESCRIPTION OF THE INVENTION
The various steps of the known method of measuring the smoke point discussed above and referred to in the preamble to the independent method claim, carried out in the procedural conditions defined in the ASTM D 1322 standard, or its equivalents, are as follows:
(a) preparing and calibrating a lamp for determining the smoke point as indicated in the standard, points 9 and 10, (b) fitting a wick measuring at least 125 mm, soaked with sample, in the wick-holder of the lamp's burner, (c) introducing 20 ml of sample into the burner's tank, (d) screwing the wick-holder with the wick onto the burner's tank, (e) cutting the top end of the wick so that it extends above the wick-holder by 6 mm and inserting the burner into the lamp, (f) lighting the wick and adjusting the wick until the flame has a height of approximately 1 cm and, after a combustion period of approximately 5 minutes, (g) raising the burner until smoke appears, then, (h) slowly lowering the burner until the flame no longer gives off smoke and presents a top end that is perfectly rounded,
The steps preliminary to identifying the sudden change in the shape of the flame are strictly in accordance with the ASTM D 1322 standard (in particular the ASTM D 1322-97 standard), or one of its technical equivalents, so there is no need to describe in detail here all the procedural conditions and safety measures making it possible to correctly carry out the method of determining the smoke point.
The step consisting in manually gradually lowering the wick of the lamp's burner to obtain a flame no longer giving off smoke and presenting a top end that is slightly rounded, of the method of the present invention, differs, however from the corresponding step (h) of the method of the ASTM D 1322 standard by the fact that a series of digital images of the flame is acquired and stored, and the stored digital images are analyzed using an appropriate image analysis system, so as to be able to deduce from it the maximum height of the flame that does not give off smoke, in other words the smoke point of the fuel under test.
To understand the invention better, the Applicant first describes the visual assessment of the maximum height of the flame that does not give off smoke as provided by the ASTM D 1322 standard, by here providing a partial transcription of point 11.4 of this standard:
11.4 Light the burner and adjust the wick so that the flame has a height of approximately 10 mm and leave the lamp burning for approximately 5 minutes. Raise the burner until smoke appears, then lower the burner slowly passing through the following flame appearance steps:
11.4.1 a long point, smoke weakly visible, flame erratic and jumpy,
11.4.2 an elongated point with lateral edges that are concave towards the top (flame A),
11.4.3 pointed end just disappears, leaving a flame that is very slightly ‘blunted’ (flame B),
11.4.4 a well rounded point (flame C). Determine the height of the flame B to the nearest 0.5 mm. Make a note of the observed height.
11.4.4.1 To eliminate parallax errors, the eye of the observer must be slightly to one side of the central line so that the reflected image of the flame is visible on the graduated scale to one side of the central vertical white line and the flame itself is visible against the other side of the graduated scale. The results of the two readings should be identical.
In the method of the present invention, the technical system for storing and analyzing images used to replace the eye of the observer serves both to determine the moment when the visible flame corresponds to the “flame B” of the standard, and to measure as accurately as possible the height of this flame B.
Analysis of the digital images stored while the burner is being lowered that is accompanied by the reduction in the size of the flame, has shown that the sudden change in the shape of the flame, that is, the appearance of the “flame B”, corresponded to a sudden change, that is easy to detect, in the speed of reduction of the Feret diameter of the image of the flame. The Feret diameter of an object is equal to the distance between two tangents to the object, parallel to each other, and defining an angle α relative to the horizontal, this angle being sometimes called “direction of measurement of the Veret diameters”. When the object is not a circle, this distance depends on the angle α defined by the tangents relative to the horizontal.
It will easily be understood that, in the case of the flame whose dimensions are to be measured, the distance between two tangents to the flame, parallel to each other and to the horizontal (α=0°) is equal to the height of the flame. This is why, in the description below, the height of the flame is sometimes called Feret diameter with angle α=0°.
The analysis of the images as such, whether analyzing the shape of the flame or its height, requires an additional operation, called “thresholding” or “binarization”, conventionally used in analyzing and processing digital images. This thresholding operation consists in setting to zero all the pixels having a gray level less than a certain value, called “threshold”, and to 1 all the pixels having a value above the threshold.
In practice, a flame is a physical phenomenon characterized by a local increase in heat and light intensity. Although the human eye believes it can distinguish a fairly clear and precise flame outline, the digital image in terms of gray levels of a flame shows that the increase in light intensity is continuous and that there is a gradual change to increasingly higher brightnesses. This brightness continuity appears clearly in FIG. 2 which represents the value of the gray levels of a line of pixels passing mid-height through the flame, perpendicular to the vertical axis of symmetry of said flame.
The sudden change in the speed of reduction of the Feret diameter, corresponding to the moment at which the “flame B” appears, is preferably determined by different measurements of the Feret diameter at an angle α that is other than zero. This angle α nevertheless has a relatively low value, preferably less than 45°. FIG. 1 shows, for four different angles α (0°, 18°, 36° and 90°), the trend of the Feret diameter (in 1/10 mm) according to the lowering of the position of the burner during the step (h) of the method. On the three curves respectively corresponding to an angle α=0°, 18° and 36°, a break point is observed, indicated by an arrow, where the slope of the curve (reflecting the speed of reduction of the height of the flame) changes suddenly. This break point or “fold” corresponds to the moment when the flame is a flame B in the sense of the ASTM D 1322 standard, for a precise position of the burner. It will be noted that, for an angle α=90° (Feret diameter corresponding to the width of the flame), this characteristic break point is not observed.
After determining the position of the burner corresponding to the flame of maximum height not giving off smoke (flame B), secondly, the absolute height of this flame is determined which, after the appropriate corrections, gives the smoke point.
The absolute value of the height of the flame B is determined by comparing it with a graduated scale which is part of the lamp described in the ASTM D 1322 standard. In the known method, the operator directly reads the height of the flame B on the graduated scale, placed behind said flame, taking the precautions indicated in point 11.4.4.1. In the inventive method, the graduated scale is not visible on the digital image of the flame stored by the CCD digital camera. The height of the flame must consequently be determined by superimposing the digital image of the flame on the digital image of the graduated scale (calibration image), taken independently by the CCD apparatus from an identical position, but in the absence of flame, and with appropriate lighting.
As for the detection of the shape of the flame corresponding to the flame B, in the sense of the ASTM D 1322 standard, determining the height of the flame also entails a digital image thresholding operation.
In practice, to determine the height of a flame, it is necessary first to decide the light intensity from which the flame begins. This decision amounts to setting a threshold (gray level value) above which it is considered that there is a flame, and below which it is considered that there is no flame. In FIG. 2 , the chosen threshold corresponds to the dashed horizontal line. The arrows A and B mark the limits of the flame for this threshold.
The difficulty lies in choosing the threshold to be used. In practice, the higher the chosen threshold is, the lower the absolute value of the height of the flame that will be obtained becomes. The appropriate threshold that is, the threshold that gives the absolute height of the flame leading to the correct smoke point of the fuel under test can be determined using one or more standard fuel mixtures (toluene/2,2,4-trimethylpentane), for which the ASTM D 1322 standard indicates the smoke point. For this, a correctly installed apparatus is used to produce a series of digital images of a combustion flame of a standard fuel mixture, and, after an appropriate thresholding operation as indicated above, the digital image corresponding to the sudden change in the speed of reduction of the Feret diameter is selected, then this image is subjected to a series of thresholding operations with different thresholds and the threshold that gives a flame height equal to the smoke point indicated by the ASTM D 1322 standard for the standard fuel mixture used is retained. The duly determined threshold must be retained throughout the series of measurements.
To complement the automation of the measurement of the smoke point of a hydrocarbon, according to the present invention, an ancillary continuous servo-control device between the position of the burner in the lamp and the triggering of image-taking by the digital camera can be installed, the burner being in this case positioned at different levels in the lamp by means of an electric motor.
Another subject of the present invention is a device for determining the smoke point of a hydrocarbon fuel. comprising:
(A) an apparatus for determining the smoke point conforming to the specifications of the ASTM D 1322 standard, (B) a digital camera, preferably a CCD digital camera, and, linked to said camera, (C) a computer system designed and programmed to enable digital images taken by the digital camera to be stored, analyzed and processed.
This device also preferably comprises an anti-infrared filter placed between the apparatus for determining the smoke point (A) and the digital camera (B), and which serves to intercept the infrared radiation emitted by the flame that would saturate the images and render them unusable.
The CCD device digital camera preferably covers wavelengths ranging from the ultraviolet to the infrared, but models covering only the visible spectrum or the visible-UV spectrum can, however, also be used. The use of an anti-infrared filter then becomes superfluous.
The dynamic range of the digital camera used to acquire the digital images is not a determining factor. To obtain images offering a satisfactory resolution, at least 10-bit CCD digital cameras should however be used, making it possible to store digital images with at least 512 gray levels. 16-bit or higher CCD digital cameras giving images with 32 768 gray levels, or more, are particularly preferred.
The CCD digital camera normally comprises a zoom and is placed at a distance of approximately 1 m to 1.5 m from the lamp of the apparatus for determining the smoke point. The zoom is then set so that the stored digital image contains the image of all the graduated scale of the apparatus for determining the smoke point. It is essential for the relative position of the CCD digital camera, relative to the lamp, not to vary between two images. The invariability of this position is, in effect, the essential condition that makes it possible to compare the different stored images and the smoke point values calculated from the latter. If, however, the position of the digital camera or the zoom setting were altered inadvertently, a new calibration image (image of the graduated scale in the absence of flame) can and must be acquired.
Given the very high sensitivity of the sensors of CCD digital cameras, a certain number of measures must be taken to ensure a good image quality. The different protocols for calibrating and eliminating background noise are familiar to those skilled in the art using CCD sensors and do not need to be described in detail here. As an example, measures ensuring a good image quality, cooling of the CCD sensors by a Peltier module, in order to eliminate the formation of so-called “thermal” charges, can be cited.
The present invention is illustrated by the following exemplary applications.
EXAMPLE 1
Validation of the Method According to the Invention by Determination of the Smoke Point of a Fuel Mixture with Known Smoke Point—determination of an Appropriate Threshold
After having installed and calibrated the wick lamp and the device according to the present invention, two successive series, each of ten digital images, are taken of a combustion flame of a mixture of 15% by volume of toluene and 85% by volume of 2,2,4-trimethylpentane (reference smoke point: 25.8 mm), the height of which is gradually reduced in accordance with the protocol described in point 11.4 of the ASTM D 1322 standard. Based on the digital images obtained, previously subjected to a thresholding of a value equal to approximately 15% of the measurement range of the CCD sensor, i.e., for this test, a value of 2000, a curve of the value of the Feret diameter of the flame is plotted, for a measurement direction α of this same Feret diameter equal to 36°, according to the position of the burner, or more precisely, according to the image number. A sudden change in the speed of reduction of the height of the flame is observed for the image number 4. Various thresholding operations are then applied to this image and the threshold that gives a Feret diameter at α=0° that is the closest to the theoretical value of the standard (25.8 mm) is retained. The duly determined threshold of 4000 gives a Feret diameter (α=0°) of 26.2 mm for the first series of images and 25.9 mm for the second series of images.
The software for analyzing and processing the two series of ten digital images, used in the present test, is supplied by Neosis, marketed by the same Visilog 6. The threshold values retained and the values of the angle α for the calculation of the corresponding Feret diameters were determined previously using different reference products according to the present invention in the procedural conditions conforming to the ASTM D 1322 standard.
EXAMPLE 2
Repeatability of the Flame Height Measurement
With a device according to the invention comprising:
(a) an apparatus for measuring the smoke point according to the ASTM D 1322 standard, (b) a CCD digital camera (16 bits) provided with a zoom, (c) linked to the digital camera, a computer with the Visilog 6 software published by Neosis installed, capable of storing, analyzing then processing the digital images originating from the digital camera, and (d) an anti-infrared filter placed between (a) and (b) three successive series, each of four digital images, are acquired, respectively corresponding to four different heights of a combustion flame of a hydrocarbon to be analyzed. The duly obtained digital images are subjected to a thresholding operation with a threshold equal to 4000, determined in the example 1.
The following flame height values are obtained (expressed in mm):
Series No.
Flame 1
Flame 2
Flame 3
Flame 4
1
15.9
11.4
9.4
5.6
2
15.9
11.2
9.4
5.6
3
16.1
11.2
9.2
5.7
Average
15.9
11.3
9.3
5.6
Standard
0.1
0.1
0.1
0.1
deviation
Calculated
0.3
0.3
0.3
0.3
repeatability
ASTM D 1322
2
2
2
2
repeatability
It can be seen that the standard deviations are of the order of 0.1 mm.
The repeatabilities obtained with the method and the device according to the present invention are of the order of 6 to 7 times better than those stated in the ASTM D 1322 standard. | The invention relates to a method for determining the smoke point of a hydrocarbon, comprising, among the different steps defined in the ASTM D 1322 standard or equivalents thereof, the identification, among different aspects of the flame according to the position of the burner in the lamp, of a particular aspect of the flame and the reading of the height of this flame on a graduated scale in mm. The invention is characterized by the fact that a series of digital images of the flame is taken and recorded with the aid of a digital camera or the like at intervals sufficiently close for permitting, by analyzing these digital images, the detection of a sudden change in the shape of the flame, and that the height of this flame is measured at the moment of this sudden change in its shape, said height being considered as the smoke point of the tested hydrocarbon. | 6 |
CROSS-REFERENCED TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. Provisional Application No. 62/353,520 filed on Jun. 22, 2016, which the disclosure of which is hereby incorporated by reference in its entirety for all purposes.
FIELD OF THE INVENTION
[0002] The disclosure relates to a door opening mechanism in a motor vehicle.
BACKGROUND OF THE INVENTION
[0003] It is a common problem that a car door cannot be opened in an easily controllable manner, particularly when the force of wind pushes the door farther open after the door has begun to open. This often results in a passenger being unable to limit how far the door swings open, and the door may hit other objects, such as an adjacent parked car or shopping cart, or the door may even bit a person. Although vehicle doors include stop mechanisms, the stop mechanisms only stop the doors when they are fully open.
SUMMARY
[0004] The present invention may provide a device that limits the cars door's swing anywhere between a fully open position to a fully closed position dependent upon when the user decides to use it. In one embodiment, the invention includes an electronically adjustable stop mechanism which enables the user to selectively limit how far the door may open. For example, if the door normally pivots 80 degrees from a closed position to a fully open position, the user may selectively limit the range of pivoting of the door when opening to a discrete value of 30 degrees, 50 degrees, or 70 degrees. Alternatively, the user may select any door pivoting range value between zero degrees and 80 degrees.
[0005] In another embodiment, the invention allows the door to open fully, but enables the user to select a level of constant braking force to be applied to the door as it opens. For example, the user may select between an additional 5 pounds, 10 pounds or 15 pounds of force being required to push open the door. Thus, the additional resistive force may enable the user to more easily control how far and how quickly the door opens.
[0006] In yet another embodiment, the invention allows the door to open fully, but enables the user to select a level of braking force to be applied to the door, wherein the level of braking force continuously increases as the door pivots farther open. For example, the user may select between the resistive force continuously increasing from one pound at the closed position to 10 pounds at the fully open position; the resistive force continuously increasing from five pounds at the Closed position to 15 pounds at the fully open position; or the resistive force continuously increasing from 10 pounds at the closed position to 20 pounds at the fully open position. Thus, the user may more easily, control how far and how quickly the door opens, particularly near the fully open position. In one embodiment, the level of braking force not only continuously increases as the door pivots farther open, but also increases asymptotically or increases parabolically as the door pivots farther open. For example, the resistive force may continuously and parabolically increase from 10 pounds at the closed position, to 20 pounds at a position half way between the closed position and the fully open position, and 100 pounds at the fully open position. Thus, as the door get closer to the fully open position, which presents the most danger, opening the door further becomes much more difficult. A dampening element may provide the resistive force.
[0007] In one embodiment, the invention comprises a motor vehicle including a body and a door pivotably attached to the body. A stop mechanism limits the pivoting of the door to an angular range. The stop mechanism is adjustable by a user such that the user may define the angular range to which the pivoting of the door is limited.
[0008] In another embodiment, the invention comprises a motor vehicle including a body and a door attached to the body such that the door is pivotable between a closed position and an open position. A dampening element is coupled between the body and the door. The dampening element provides mechanical resistance to the pivoting of the door from the closed position to the open position.
[0009] In yet another embodiment, the invention comprises a motor vehicle including a body and a door attached to the body such that the door is pivotable between a closed position and an open position. A dampening element is coupled between the body and the door. The dampening element provides an increasing level of mechanical resistance to the pivoting of the door as the door is pivoted from the closed position to the open position.
[0010] An advantage of the present invention is that it may enable a user to more easily control or limit the opening of a vehicle door.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings.
[0012] FIG. 1 is a schematic diagram of one example embodiment of a car door swing control arrangement of the present invention.
[0013] FIG. 2 is a schematic view of one embodiment of a control device which a user may use to control the car door swing control arrangement of FIG. 1 .
[0014] FIG. 3 is a schematic diagram of one example embodiment of a dampening apparatus which may be included in the car door swing control arrangement of FIG. 1 .
[0015] FIG. 4 is a schematic view of one embodiment of a control device which a user may use to control the dampening apparatus of FIG. 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] FIG. 1 illustrates one embodiment of a car door swing control arrangement 10 of the present invention, including a vehicle 12 having a door 14 which may pivot about 80 degrees between a closed position 16 and a fully open position 18 . A door stop 19 , which is only schematically indicated in FIG. 1 , may be in position to limit the opening of door 14 to the fully open position 18 . According to the invention, the position of the door stop may be selectively adjustable so that the door stop may limit the opening of door 14 to any of the semi-open positions indicated at 20 , 22 and 24 . The door may be pivotable within a range of about 70 degrees, 50 degrees, and 30 degrees, respectively, in positions 20 , 22 and 24 . The position of door stop 19 may be movable mechanically and/or hydraulically, and may be controlled by the user via an electrical or electronic control device within the passenger compartment.
[0017] FIG. 2 is a schematic view of one embodiment of an electrical or electronic control device 28 which a user may use to control the car door swing control arrangement of FIG. 1 . The control device includes a pin 30 disposed in an arcuate slot 32 representing the path of the outer edge of ear door 14 as the door opens. With pin 30 in the position 34 at the outer end of slot 32 , the position of door stop 19 may be such that door 14 can be opened to the fully open position 18 . However, if pin 30 is moved to position 36 , the position of door stop 19 may also be caused to move such that the opening of door 14 is limited to the semi-open position indicated at 20 . Similarly, if pin 30 is moved to position 38 , the position of door stop 19 may also be caused to move such that the opening of door 14 is limited to the semi-open position indicated at 22 ; and if pin 30 is moved to position 40 , the position of door stop 19 may also be caused to move such that the opening of door 14 is limited to the semi-open position indicated at 24 .
[0018] FIG. 3 illustrates one example embodiment of a dampening apparatus 42 which may be included in the car door swing control arrangement 10 of FIG. 1 . Dampening apparatus 42 includes a dampening element 44 which may be similar to a shock absorber. Dampening element 44 includes a hydraulic cylinder 46 having a fixed rod 48 extending from a first end of cylinder 46 , and a slidable rod 50 extending from a second end of cylinder 46 . An outer end of rod 48 is pivotably attached to a fixed structure 52 , and an outer end of rod 50 is slidingly coupled to car door 14 . As door 14 further opens from the position indicated at 54 to the position indicated at 56 , rod 50 slides out of cylinder 46 , and the outer end of rod 50 slides along the length of door 14 .
[0019] Dampening element 44 may provide resistance or a dampening force that resists the force with which the user pushes on door 14 in order to open door 14 . Thus, the user is required to exert more force on door 14 in order to open the door, which may enable the user to better control how far the door opens. In one embodiment, dampening element 44 applies a constant level of resistance to the opening of door, regardless of how far the door has already been opened. In another embodiment, dampening element 44 applies an increasing level of resistance as door 14 opens farther, thus providing the user with an increased level of control on the door as the door approaches the limit of how far it can open, which is where the door is also most likely to collide with another object. In yet another embodiment, dampening element 44 applies not only an increasing level of resistance as door 14 opens farther, but applies an asymptotically increasing or parabolically increasing level of resistance as door 14 opens farther.
[0020] FIG. 4 is a schematic view of one embodiment of a control device 58 which a user may use to control the dampening apparatus of FIG. 3 . Control device 58 may include a dial 60 having an indicator 62 which may be rotated to a maximum force position, a minimum force position, or any position in-between. The position of dial 60 may control a hydraulic pump (not shown) which pumps hydraulic fluid into or out of hydraulic cylinder 46 , and thereby affects the level of resistive force that dampening element 44 exerts on door 14 .
[0021] A vehicle may include the dooring limiting apparatus of FIGS. 1-2 without the dampening apparatus of FIGS. 3-4 ; may include the dampening apparatus of FIGS. 3-4 without the dooring limiting apparatus of FIGS. 1-2 ; or may include both the dooring limiting apparatus of FIGS. 1-2 and the dampening apparatus of FIGS. 3-4 .
[0022] The invention may be disabled in the event of a user pressing a panic button (not shown) within a vehicle passenger compartment; an air bag deployment; a moisture sensor that is shielded from rain and road spray detecting that the vehicle is under water; or a heat sensor detecting that the vehicle is in a fire. In case of such disablement, door 14 may be opened as freely as if car door swing control arrangement 10 were not in place.
[0023] The foregoing description may refer to “motor vehicle”, “automobile”, “automotive”, or similar expressions. It is to be understood that these terms are not intended to limit the invention to any particular type of transportation vehicle. Rather, the invention may be applied to any type of transportation vehicle whether traveling by air, water, or ground, such as airplanes, boats, etc.
[0024] The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom for modifications can be made by those skilled in the art upon reading this disclosure and may be made without departing from the spirit of the invention. | A motor vehicle includes a body and a door pivotably attached to the body. A stop mechanism limits the pivoting of the door to an angular range. The stop mechanism is adjustable by a user such that the user may define the angular range to which the pivoting of the door is limited. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to electrical lighting. More specifically, the present invention relates to illuminated cabinet soffits and aprons for wall-mounted hanging kitchen cabinets and other wall-mounted hanging cabinets commonly installed in the home, shop, and workplace.
[0003] 2. Description of the Related Art
[0004] Wall-mounted hanging cabinets are a nearly universal means of providing storage space for various articles in a number of different environments. Such cabinets can vary greatly in their vertical extent and mounting height, but are generally mounted with their bases about five feet above the floor. Such cabinets are generally about two to two and one-half feet high from bottom to top, which results in a gap of between six inches and one foot in height above the cabinets in the case of the typical eight-foot high ceiling of most structures in the U.S. This above-cabinet open space is often used to store infrequently used articles and for running additional wiring, conduit, pipe, etc. Whatever the actual use to which this above-cabinet gap is put, the result is generally rather unsightly.
[0005] As a result many people will cover this above-cabinet gap with a closure panel or soffit of some sort, generally without lighting or any particular decorative aspects. In some cases, the soffit panels may be ornamented or decorated in some manner, but very few have included any lighting. Where lighted soffits have been developed, they generally use a translucent panel with no decorative pattern to serve as room lighting. In any event, such soffit panels are generally permanently installed, with no provision for changing the appearance of the soffit panels without major remodeling effort.
[0006] Under-cabinet lighting is also often installed beneath such hanging wall cabinets. Such under-cabinet lighting is used to illuminate the underlying countertops or the like. Often, an apron is attached to the lower edge of the wall-mounted cabinetry to block generally horizontal light emission directly into the eyes of a person in the area of the cabinetry. As such, there is generally no provision for light output through the apron. These aprons at best generally have only rudimentary ornamental appearance to match the adjacent cabinetry; seldom is any additional ornamentation provided. As in the case of conventional soffit installations, there is generally no provision for modifying or changing the appearance of such aprons without a fair amount of remodeling work.
[0007] The present inventor is aware of various examples of lighting installed with cabinetry. One such example is found in Japanese Patent No. 4-193,215 published on Jul. 13, 1992, which describes (according to the drawings and English abstract) an under-cabinet lighting system actuated by a photocell. A light barrier is installed surrounding the under-cabinet light, depending from the bottom of the overlying cabinet. The photocell is installed exterior to the light and light barrier in order to detect variations in the lighting pattern without being affected by the under-cabinet lighting.
[0008] Japanese Patent No. 4-341,219 published on Nov. 27, 1992, describes (according to the drawings and English abstract) a single lighting unit for a divided produce case or the like. The single light is installed in a partition between the two sections of the case, thereby projecting light into both sections.
[0009] None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus, illuminated cabinet soffits and aprons solving the aforementioned problems are desired.
SUMMARY OF THE INVENTION
[0010] The illuminated cabinet soffits and aprons, collectively addressed as illuminated cabinet panels, are installed to extend between the upper edge of hanging wall-mounted cabinet and the overlying ceiling structure and to depend from the lower periphery of such wall-mounted cabinets. Each of the soffit and apron panels includes at least one light passage therethrough, with a corresponding pocket for holding a removable light transmitting pane therein. The pocket may be formed by cutting a saw kerf between and parallel to the two faces of the panel, by spacing apart the front and rear sheets of the panel with a series of ribs or spacers, or by applying a series of such ribs to the back surface of the panel and applying wider webs to those ribs. The upper edge of the pocket is always open, permitting access to the translucent pane therein for removal thereof and interchange with another pane for changing the color, etc.
[0011] Preferably, each soffit or apron panel has a plurality of light passages therethrough, with a pocket generally centered therebehind for holding a translucent pane therein. The light passages on at least the front face of the panel may be in any decorative or other form or shape as desired, e.g., various regular or irregular geometric shapes, caricatures, outlines of various articles such as automobiles, airplanes, locomotives, etc., or shapes of various articles relating to an occupation or hobby, e.g., musical instruments, etc. The light opening formed in the rear face of the panel may be an easily formed regular shape, e.g., a circular opening, etc.
[0012] In addition to providing for the interchange of different translucent panels in the pockets of the panels, the panels themselves may be removably installed within the front of the soffit space or below the edges of the cabinets if so desired. Such a removable installation permits the panels to be readily interchanged to provide light openings having different themes, if so desired. The soffit and apron panels may be provided in prefabricated lengths, with joining brackets provided for assembling two or more such soffit or apron panels end-to-end to provide a longer run, if so desired.
[0013] These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is an environmental, perspective view of kitchen cabinets incorporating the illuminated cabinet soffits and aprons according to the present invention, illustrating an exemplary installation.
[0015] FIG. 2 is an exploded perspective view of a first embodiment of illuminated cabinet soffits and aprons according to the present invention, showing the insertion of translucent panes therein.
[0016] FIG. 3 is a fragmented, exploded perspective view of the end assembly of two panels of the illuminated cabinet soffits and aprons according to the present invention, showing their assembly.
[0017] FIG. 4 is an end view in section of a soffit space above a cabinet, showing provision for removable illuminated soffit panels.
[0018] FIG. 5 is an exploded perspective view of an alternative embodiment of illuminated cabinet soffits or aprons according to the present invention.
[0019] FIG. 6 is an exploded perspective view of another alternative embodiment of illuminated cabinet soffits and aprons according to the present invention.
[0020] Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The present invention relates to illuminated cabinet soffits and aprons (collectively described as “panels”) for installation with cabinets and similar environments. Each of the soffits and aprons includes at least one pocket therein for the removable installation of a pane capable of transmitting light therethrough, with each of the panels preferably being elongate and including a series of such pockets therein. The panes may be exchanged to provide decorative lighting of different colors or producing different lighting effects.
[0022] FIG. 1 of the drawings provides an illustration of a cabinet installation, including a series of illuminated soffit panels 10 and apron panels 50 . FIG. 2 illustrates further details of the soffit and apron panels. Each of the panels or boards 10 and 50 is formed of a single, unitary length of material (e.g., wood board, metal, plastic, etc.) with a series of pockets 12 cut therein for holding corresponding translucent panes. Each of the pockets 12 may be formed as a saw kerf, or routed or otherwise cut from the material between the front and rear faces 14 and 16 of the soffit or apron panel 10 or 50 . The pockets 12 are cut through the upper edges of the soffit and apron panels 10 and 50 , but do not extend through the bottom edges of the panels. Each of the pockets 12 is discrete from its adjacent pocket to provide a plurality of separate and distinct pockets in each soffit and apron panel 10 and 50 .
[0023] The front face 14 of each soffit and apron panel 10 and 50 includes at least one light passage 18 formed therethrough in the corresponding pocket 12 , with the opposite rear face 16 having a corresponding light passage 20 formed therethrough. The light passages 18 and 20 are at least generally aligned with their corresponding pocket 12 to allow light to pass through the pocket 12 and passages 18 , 20 from the back to the front of the board or panel 10 or 50 . The rear light passages 20 may be any suitable or practicable shape, so long as they allow light to pass or diffuse through essentially the entire front light passages 18 . The front light passages 18 may have any desired shape, e.g., regular or irregular geometric shapes, silhouettes or outlines of caricatures, objects or articles used in one's occupation or hobbies, etc. For example, the front light passages 18 of the soffit panels 10 of FIG. 1 is an alternating series of heart shapes 18 a and diamond shapes 18 b , while the front light passages 18 c of the aprons 50 are relatively simple circular shapes. Such circular shapes are easily formed with a hole saw, while more complex shapes may be routed, laser cut, etc. using known technology.
[0024] FIG. 2 illustrates the backlighting of an exemplary soffit panel 10 or apron panel 50 using a conventional fluorescent tube 22 disposed behind the soffit or apron panel. Other forms of lighting may be used, e.g., incandescent, light emitting diodes (LEDs), etc. The panel 10 , 50 of FIG. 2 differs further from the soffit 10 and apron 50 of FIG. 1 in that the panel includes four different cutouts or shapes for the front light passages, i.e., a spade-shaped passage 18 d , the heart-shaped and diamond-shaped passages 18 a and 18 b also being used in the soffit panel 10 of FIG. 1 , and a club-shaped passage 18 e . Such a soffit or apron panel might be installed in a den or recreational room in a home, or perhaps a casino or other area where card games are played from time to time.
[0025] Each pocket 12 has a pane 24 capable of transmitting light therethrough removably installed or placed therein, as shown in FIG. 2 . The light transmissible panes 24 may actually be completely clear or transparent, but are preferably tinted, frosted, or otherwise made to be translucent. The panes 24 may be provided in any color(s), e.g. a relatively dark color, such as a dark blue or a neutral gray tint for the spade- and club-shaped light passages 18 c and 18 d , and a red tint for the heart- and diamond-shaped light passages 18 a and 18 b of the panel 10 , 50 of FIG. 2 , to represent at least the approximate colors of those suits in a deck of cards. Other colors may be provided, e.g., green for leaf-shaped light passages, appropriate colors for passages having the shapes of specific species of flowers, etc.
[0026] The soffit and apron panels 10 and 50 are preferably provided as prefabricated modules, i.e., precut to predetermined lengths, with precut shapes for the front light passages 18 . Customers may select the style desired in keeping with their desires for decorating the room or other area in which the panels 10 , 50 are to be installed. As the panels 10 , 50 are provided in predetermined lengths, e.g., four feet or so, a series of such panels must be placed end-to-end to span a longer distance. FIG. 3 provides an illustration of a portion of a first panel 10 or 50 having a circular front light passage 18 c , octagonal and hexagonal front light passages 18 f and 18 g , and a first end 26 . A separate but identical second panel 10 , 50 includes triangular and a square front light passages 18 h and 18 i , respectively, and opposite first and second ends 26 and 28 . An end having an I-beam shape joining bracket 30 having a central web essentially equal in width to the thickness of the two panels and two opposed flanges is placed upon the adjacent first and second ends 26 , 28 of the two panels to secure them to one another in a continuous line. The panels 10 , 50 may be slid from the bracket 30 , e.g., to remove the panels 10 , 50 for maintenance to any light fixture installed therebehind, for changing the color(s) of the pane(s) installed therein, etc.
[0027] The illuminated cabinet soffits 10 and aprons 50 are preferably removably installed, rather than being permanently installed, in order to allow for maintenance to the light fixture and exchange of the various light panes, as noted above. FIG. 4 provides an illustration of such a removable soffit panel 10 installation. In FIG. 4 , an inverted and relatively deep, generally U-shaped upper edge channel 32 is installed to the overhead ceiling panel P along the forward edge of the soffit space S above the forward edge of the cabinets C. An opposite, generally U-shaped lower edge channel 34 is secured along the upper and forward edge of the cabinets C, with the two open channels 32 and 34 facing one another.
[0028] The vertical span of the installed soffit panel 10 is slightly less than the distance between the bases of the two channels 32 and 34 , thus allowing some vertical play when the soffit panel 10 is installed in the two channels 32 and 34 . When the soffit panel 10 is lifted so that its upper edge 36 contacts the inner base or floor of the upper edge channel 32 , the lower edge 38 of the soffit panel 10 is slightly above the upstanding edges or sides of the lower edge channel 34 . This allows the soffit panel 10 to be swung outwardly, as shown in broken lines in FIG. 4 , for removal from its installed position for access to the light fixture 22 therebehind, for exchanging one or more of the translucent panes installed within the soffit panel 10 , or perhaps for exchanging the entire soffit panel 10 for one with a different appearance. The apron panels 50 may be removably installed below the forward edge of the cabinetry by a similar channel configuration, with the lower edge channel 34 being suspended from a series of vertical ties extending downwardly from the bottom of the cabinetry or the overlying upper edge channel 32 .
[0029] The soffit and apron panels may be constructed of a plurality of pieces or components, rather than being formed from a single unitary sheet of wood or other material, as in the case of the soffit and apron panels 10 and 50 of FIGS. 1 through 4 . FIG. 5 provides an exploded perspective view of such an alternative soffit and apron construction. The soffit 110 or apron 150 of FIG. 5 includes a front sheet 114 and a separate rear sheet 116 separated by further structure therebetween and described further below. The front sheet 114 has a front surface 114 a and an opposite rear surface 114 b , with a plurality of front sheet light passages 118 a , 118 b , 118 c , etc., being formed therethrough. The exemplary front light passages 118 a through 118 c of the soffit 110 or apron 150 panel assembly of FIG. 5 are in the form of silhouettes of musical instruments. Again, the various front light passages (or light passages through the rear face or sheet, for that matter) may be in any desired form or shape. The rear sheet 116 serves as a pane-retaining member and includes a front surface 116 a and opposite rear surface 116 b , with a plurality of rear sheet light passages 120 being formed therethrough. The front light passages 118 and rear light passages 120 are at least generally aligned with one another when the soffit or apron panel 110 , 150 of FIG. 5 is assembled.
[0030] A plurality of additional structural members are installed between the two sheets 114 and 116 to separate the two sheets and provide pockets 112 for the light panes to be installed therein. A single elongate lateral spacer 140 is secured along the lower edge of the rear surface 114 b of the front sheet 114 and along the lower edge of the front surface 116 a of the rear sheet or pane retaining member 116 . A series of vertical spacers 142 are also secured to the rear surface 114 b of the front sheet 114 and to the front surface 116 a of the rear sheet 116 between the light passages 118 and 120 . The lateral spacer 140 , thus, defines the bottom of a plurality of pockets 112 for removably holding the light panes, with the vertical spacers 142 defining the lateral limits of the pockets 112 . The front and back surfaces 114 b , 116 a of the front 1 14 and rear 116 sheets define the front and rear limits of the pockets 112 . The upper edges of the pockets 112 remain open to permit the insertion and removal of light panes therein, e.g., light pane 24 of FIG. 2 .
[0031] FIG. 6 is an exploded rear perspective view of yet another embodiment of the illuminated cabinet soffits and aprons, comprising a soffit 210 or apron 250 . The soffit or apron 210 , 250 of FIG. 6 includes a front sheet 214 having a front surface 214 a and opposite rear surface 214 b , as in the case of the embodiment of FIG. 5 . A series of front face light passages, e.g., circular light passages 218 , or other shape(s) as desired, are provided through the front sheet 214 . As in the case of the built-up soffit or apron panel 110 , 150 of FIG. 5 , the front sheet 214 and the rear retaining member are separated by a single elongate lateral spacer 240 secured along the lower edge of the rear surface 214 b of the front sheet 214 . A series of vertical spacers 242 are secured to the rear surface 214 b of the front sheet 214 between each of the light passages 218 . The front sheet 214 defines the front of each pocket 212 , with the lateral spacer 240 and vertical spacers 242 defining the bottom limits and lateral limits of the pockets 212 .
[0032] However, rather than having a pane-retaining member comprising a single, continuous rear sheet as in the embodiment of FIG. 5 , the backs of the translucent pane pockets 212 are defined by a plurality of separate, relatively wide webs. In the example of FIG. 6 , a single, relatively wide lower lateral web 244 is secured to the back of the lateral spacer 240 and the lower portions of the vertical spacers 242 . A relatively wide vertical web 246 is secured to each of the vertical spacers 242 . These lateral and vertical webs 244 , 246 do not extend across the entire span of each of the pockets 212 in order to provide a rear light passage between each adjacent vertical web 246 , but they do extend sufficiently far to prevent the light panes, e.g., pane 24 of FIG. 2 , from falling laterally away from the front sheet 214 . It will be seen that the single lateral web 244 may be eliminated if so desired, with the backs of the pockets 212 being defined or limited by the lateral extent of each of the wide vertical webs 246 extending beyond their respective vertical spacers 242 .
[0033] In conclusion, the illuminated cabinet soffits and aprons enable persons to quickly and easily change the appearance of a room or other area incorporating such panels. Rather than permanently securing the light panes to the rear surfaces of the panels, the user of such soffit and apron panels may merely remove the panel from its installation and remove and replace the light panes from the pockets within the panels, or exchange the entire soffit or apron panel for another configuration or style, if so desired. The modular nature of the soffit and apron panels facilitates installation and interchange by the homeowner or other person making use of such panels without requiring extensive remodeling or carpentry work to do so. The resulting savings in time and expense in comparison to changes to conventional light panels will prove to be most valuable to the owner or user.
[0034] It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | The illuminated cabinet soffits and aprons each include at least one pocket formed therein for removably placing a panel capable of transmitting light therethrough. The pockets may be formed by cutting a saw kerf between the two opposite panel faces, by separating the front and rear sheets of the panel with spacers, or by adding spacers to the back of a front sheet and attaching a series of webs to the spacers. The front of each panel includes at least one light passage therein. The light passage may have any regular or irregular geometric shape, or may be in the outline of a caricature, an object or symbol relating to an occupation or hobby, etc. The light passage through the rear of the panel may be any desired shape. Various attachments may be provided for removably attaching the panels to the cabinets for interchanging the panels. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation application, under 35 U.S.C. §120, of copending international application No. PCT/EP2015/054181, filed Feb. 27, 2015, which designated the United States; this application also claims the priority, under 35 U.S.C. §119, of German patent application No. DE 10 2014 203 773.5, filed Feb. 28, 2014; the prior applications are herewith incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention relates to an induction cable containing a plurality of cable cores which each have a conductor strand which is surrounded by insulation. The conductor strand contains a plurality of conductor sections which are spaced apart by respectively insulating intermediate regions with at least one insulating intermediate piece at resonance separation points in a cable longitudinal direction. The invention further relates to a coupling device for an induction cable of this kind, and also to a method for producing an induction cable of this kind.
[0003] An induction cable of this kind, also called an inductor, serves to form one or more so-called induction fields. In this case, the induction cable is provided, in particular, for inductively heating oil sand and/or ultra-heavy oil deposits. An application of this kind for an induction cable of this kind can be found, for example, in European patent EP 2 250 858 B1, corresponding to U.S. Pat. No. 8,766,146. The technical boundary conditions resulting from this application are met by the induction cable.
[0004] In order to build up the induction fields and implement inductive heating, it is necessary for the individual cable cores of the cable to be separated at defined separation points into contact spacing with a defined length of, for example, several tens of meters. In the process, each of the cable cores is subdivided by the separation points into a number of core sections.
[0005] Within the cable, a plurality of cable cores is preferably combined to form core groups, wherein the separation points or interruptions of the cores of a respective core group are situated substantially at the same longitudinal position. There are typically two core groups, the separation points of the core groups being shifted by half the contact spacing relative to one another. In other words: the separation points of a first core group are arranged at half the distance between two separation points of a second core group in the longitudinal direction. As a result, the core sections of different groups overlap, this serving, in particular, to form an induction cable.
[0006] A cable of this kind is described, for example, in international patent disclosure WO 2013 079 201 A1, corresponding to U.S. patent publication No. 2014/0263289. This document discloses a cable core for a cable, in particular for an induction cable, containing a plurality of cable cores of this kind which each have a conductor which is surrounded by insulation. Furthermore, the respective cable core, that is to say a conductor which is surrounded by an insulation sheath, is interrupted at prespecified longitudinal positions at separation points in the cable longitudinal direction so as to form two core ends. In order to connect the core ends, a connector containing an insulating intermediate piece is provided and the core ends are fastened to the connector on both sides of the intermediate piece. In order to connect the core ends, the connector is of sleeve-like design at its opposite end sides, so that a respective core end, that is to say also a portion of the insulation sheath in particular, is surrounded.
[0007] Induction cables of this kind are usually drawn into the induction field in prepared pipes. The length of a respective induction cable is from several hundred meters to kilometers in this case.
[0008] In this case, an induction cable of this kind is typically made up of a plurality of core bundles which are, in particular, braided together. In this case, the overall braided composite typically has a diameter in the range of several centimeters, for example in the range of from 5 to 20 cm.
[0009] Providing and laying an encompassing induction cable of this kind is technically complicated.
SUMMARY OF THE INVENTION
[0010] Against this background, the object of the invention is to specify an improved induction cable which is easier to provide and to lay.
[0011] According to the invention, the object is achieved by an induction cable having the features of the main claim. According to the main claim, the induction cable contains a plurality of cable cores which each have a conductor strand which is surrounded by insulation and which contains a plurality of conductor sections which are spaced apart by insulating intermediate regions at resonance separation points in the cable longitudinal direction. The intermediate region is formed by at least one insulating intermediate piece, an intermediate piece of this kind is at least arranged in the intermediate region. Furthermore, a coupling device is integrated into the induction cable and at least a plurality of the conductor strands are interrupted at a coupling position and each have a pair of coupling ends which are connected to one another at the coupling position with the aid of the coupling device.
[0012] Two different variant embodiments of the coupling device are provided in principle, specifically connection of only a number of conductor strands or connection of all of the conductor strands. At least in the first-mentioned case, the coupling device has a coupling module as an additional component which is provided with receptacles for the coupling ends. A plurality of the conductor strands are jointly held on the coupling module by way of their coupling ends. In the second-mentioned case, the cable is therefore divided at the coupling point so as to form two cable ends which are connected to one another by the coupling device.
[0013] The coupling device therefore provides a unit for connecting a plurality of the conductor strands, for example half of the conductor strands or all of the conductor strands, so that this plurality of conductor strands can be connected to one another jointly in a simple manner by the coupling device.
[0014] In general, production, provision or laying of the induction cable is simplified by the coupling device. In all cases, the induction cable specifically does not have to be produced in one piece over its entire length. Instead, it can be subdivided into individual subsections. In the case of the second-mentioned variant with the complete separation, individual partial cable pieces are therefore provided, the partial cable pieces having to be provided as such at the laying location in the induction field and having to be connected to one another only immediately during laying. This allows simplified transportation and also simpler handling overall. Furthermore, this also makes repair simpler since only the defective partial cable piece has to be replaced if there is a defect.
[0015] In addition, quality control is simplified in both variants since, in the event of a quality deficiency, it is only necessary to replace the defective partial piece in a simple manner during production. It is also easier to check individual partial pieces than with a complete cable with a length of several hundred meters to a few kilometers.
[0016] The first-mentioned variant of the coupling device, in which only some of the conductor strands are connected by the coupling device, advantageously makes use of the fact that the individual conductor strands contains individual conductor sections which are separated from one another by the intermediate regions and have a prespecified length. Therefore, during production, the individual conductor sections can be provided as individual lengths with a defined spacing length with the aid of the coupling device and can be connected to one another by the coupling device.
[0017] For the second-mentioned case of complete separation of the induction cable at the coupling position, the coupling device has two coupling parts for combining the two cable ends. The two cable ends are received and held in these two coupling parts, and the coupling device is designed, overall, in the manner of a plug connection, screw connection or else latching connection. The two coupling parts are combined in the cable longitudinal direction during connection. The individual separated conductor strands of the induction cable are then automatically connected during this combination process.
[0018] In a preferred refinement, the coupling device is configured as a connection which can be reversibly released, so that the individual coupling ends, in particular the two cable ends, can be reversibly connected to one another by the coupling device. This allows simple disconnection, even after assembly has taken place, for example in order to replace a defective subsection.
[0019] The individual coupling ends of the individual conductor strands are preferably combined by plug connections. According to a first variant, plug connection elements are fitted to the coupling ends, for example welded, soldered, crimped or else injected-molded onto said coupling ends, for this purpose. As an alternative to this, the coupling ends are plugged into the receptacles of the coupling module or into suitable connection pieces which are situated in the receptacles. The coupling ends are preferably prepared in a suitable manner in both cases.
[0020] According to a preferred development, the coupling device is arranged at the resonance separation point, which is to say at a longitudinal position of the induction cable at which some of the conductor strands have intermediate pieces. A plurality of groups of conductor strands are preferably formed in the induction cable, in particular two groups, wherein each group has the intermediate regions at identical longitudinal positions. The conductor ends of the conductor strands, which conductor ends are opposite one another, form the coupling ends in this case. Therefore, the intermediate regions are integrated in the coupling module. The coupling module therefore has a plurality of first receptacles of a first connection type, wherein in each case at least one intermediate piece is arranged in each of the first receptacles.
[0021] In this case, the individual groups of conductor sections are usually spaced apart from one another by a defined distance which is constant over the cable longitudinal direction. When there are two groups, this distance is half the contact spacing, that is to say half the spacing between two resonance separation points.
[0022] In an expedient refinement, the coupling module contains a plurality of second receptacles of a second connection type, wherein the two coupling ends are electrically conductively connected to one another in the second receptacles. In this case, the conductor strand is therefore interrupted in the region of a respective conductor section by the coupling device and electrically conductively connected by the coupling device. A refinement with second receptacles of this kind also allows positioning of the coupling device at an axial longitudinal position at which no intermediate pieces are arranged.
[0023] In a particularly preferred refinement, it is provided that the coupling module has both first receptacles with the integrated intermediate pieces and second receptacles for electrically conductive connection. In this case, the coupling device serves for complete separation and connection of the induction cable so as to form two cable ends.
[0024] Within the conductor strand composite of the induction cable, the different groups of conductor strands are usually arranged in a manner distributed in line with a prespecified pattern, in particular in such a way that a conductor strand of one group is in each case arranged next to the conductor strand of the other group. As a result, an insulating intermediate piece is therefore usually positioned alternately next to a conductor section in the region of a resonance separation point. The individual conductor strands typically form an, in particular, multilayer conductor bundle, in particular a multi-layer braided composite. By way of example, two layers are arranged around a central strand. The first layer has, for example, six cores and the second layer has 12 cores.
[0025] With regard to connection of the coupling ends which is as simple as possible, sleeves are expediently arranged in the receptacles, the coupling ends being inserted and, in particular, plugged into the sleeves. The sleeves are selectively composed of an insulating material or of a conductive material. In the first-mentioned case, the sleeves preferably form an intermediate piece for forming a resonance separation point. The sleeves are formed, for example, as a double sleeve with an intermediate piece arranged between opposite sleeve sections. The material used for the insulating sleeve is, in particular, ceramic, in order to achieve a high level of resistance to partial discharge.
[0026] The coupling connection is expediently formed between the coupling ends or a fastening of the coupling ends in the sleeves with the aid of a profiled portion. To this end, the respective sleeve is provided, selectively or else in combination, with an at least partially profiled inner wall and/or a profiled portion is formed at the coupling ends themselves. According to a first variant embodiment, the profiled portion is configured as a pull-out protection device in this case, so that a high pull-out resistance in the axial direction is therefore formed. The profiled portions are formed, for example, in the manner of ribs which run, in particular, in a circular manner, or else in the manner of barbs. In a preferred refinement, a thread is formed by the profiled portion, so that the two parts can be screwed one into the other. In the variant embodiment with sleeves, the sleeve therefore has thread elements on its inner wall and, in a manner corresponding thereto, the coupling end which is to be inserted into the sleeves likewise has a thread element, so that the two partners can be connected to one another by being screwed one into the other.
[0027] Expediently, the coupling ends are preferably additionally each provided with a termination piece, a separate sub-element therefore being fastened to the coupling ends. In this case, said separate sub-element preferably has the profiled portion. According to a first variant, these termination pieces are, in particular, cap-like elements in the form of termination caps which are placed on the coupling end over the respective end region. The termination pieces are, in particular, welded metal caps for example. As an alternative, insulating caps are fitted, wherein the insulating caps expediently also form the insulating intermediate piece at the same time. Therefore, there is no need to form an integral continuous intermediate piece. Therefore, two insulating caps, which are separated from one another around possibly include an air gap between them, can also be arranged in the insulating intermediate region as intermediate pieces. As an alternative to the cap-like elements, cylindrical, bolt-like elements can also be arranged, in particular welded, as termination pieces.
[0028] In order to allow simple connection of the individual coupling ends, the coupling module expediently has an approximately star-shaped carrier which has a plurality of receptacles for the coupling ends. This refinement relates, in particular, to the variant embodiment in which only some of the conductor strands are coupled. The carrier has carrier arms and therefore an approximately branched structure, wherein, in particular, the first receptacles are formed on the carrier.
[0029] In the case of a carrier of this kind, in each case one receptacle is provided in the region of a resonance separation point at the positions which the individual conductor strands in the cable composite assume. Therefore, the same conductor strand pattern as is also present in the induction cable is replicated by the carrier. It is therefore ensured that the conductor strand composite is maintained and the individual conductor strands do not need to be moved from the bundle arrangement to a connection plane, for example.
[0030] The coupling module, in particular the carrier, expediently has a plurality of recesses through which—in the region of the resonance separation point—the conductor sections are guided without interruption. The conductor sections are therefore not separated.
[0031] The carrier is designed as a separate component which is formed, for example, in the manner of a thick circular disk with a branched structure. The continuous conductor sections are inserted into the recesses in a simple manner. In this case, the recesses are expediently accessible radially from the outside, that is to say are open to the outside.
[0032] In this respect, the approximately star-shaped carrier separates the two groups of conductor strands from one another and is therefore also called a separating star in the text which follows.
[0033] In this case, the coupling module, in particular the carrier, is expedeiently configured as an injection-molded part. The injection-molded part is provided as a prefabricated part to which the coupling ends are then attached and connected to one another.
[0034] In a preferred development, the induction cable has a functional line, specifically, for example, a strain-relief device, a sensor line or else a data line, which is guided by the coupling device either without interruption or so as to form two partial pieces which are connected to one another. The sensor line is, for example, a fiber-optic cable, preferably for temperature measurement. Data can be transmitted along the cable with the aid of the data line. In a preferred variant, these lines are therefore connected to one another in the manner of line connectors to one another with the aid of the coupling device. In the case of pure guidance, a recess is preferably also formed in the carrier for this functional line, so that the functional line can be laterally introduced in the radial direction.
[0035] The receptacles are expediently oriented in the direction of a connection direction which is at a prespecified angle in relation to the cable longitudinal direction. Therefore, the connections are not oriented parallel to the longitudinal direction. This refinement is based on the consideration that, in particular in the case of helically running conductor strands, for example as a result of braiding, the receptacles are preferably obliquely oriented in order to accommodate the respective direction of the conductor strands, so that the conductor strands are guided further through the receptacles over their course. The orientation of the receptacles, that is to say the connection direction of the receptacles, corresponds, in particular, to a pitch or orientation of the conductor strands in this case.
[0036] The provision of a separate component within the cable by the coupling device provides a way of integrating additional functional elements into the cable. A sensor module is preferably integrated in the coupling device. In this case, the sensor module contains at least one sensor for detecting values of parameters, selectively cable parameters, for monitoring the function of the cable or else environmental parameters for ascertaining properties of the area surrounding the cable. Particularly when detecting measurement values relating to environmental parameters, effective monitoring and checking of the area surrounding the induction cable, that is to say in particular of the entire induction field, can be achieved in a simple manner. The measurement data is expediently transmitted to an evaluation unit. To this end, the transmission is provided, in particular, by the above-mentioned data line which is integrated into the cable as a functional line.
[0037] According to the invention, the object is further achieved by a method for producing an induction cable, in which method a plurality of coupling ends are connected to one another with the aid of a coupling device.
[0038] The advantages cited in respect of the induction cable and preferred embodiments can analogously also be transferred to the method.
[0039] Two cable ends are expediently connected to one another by the coupling device, specifically preferably in such a way that the cable ends are rotated relative to one another about the cable longitudinal direction in the event of connection by the coupling device. Owing to the rotation, in particular a helical pitch of the individual conductor strands is recorded and/or tracked. This variant embodiment is provided, in particular, in combination with the receptacles which are oriented obliquely in a connection direction, so that, that is to say owing to this rotational movement, the individual cable ends or the individual coupling ends of the conductor strands are introduced into the receptacles parallel to the connection direction.
[0040] In an expedient refinement, for the purpose of producing the induction cable, the individual conductor sections are provided as individual lengths and connected to one another by the coupling device so as to form the resonance separation points. Here, connection is intended to be understood to mean that the coupling ends are held in a manner separated from one another by an insulating intermediate piece. The coupling device contains, for example, a ceramic element as an intermediate piece for this purpose. Therefore, partial cable core pieces, in particular with the prespecified spacing or resonance length, are provided between two resonance separation points and connected to one another by the coupling device at the resonance separation points. The above-described separating star in particular is provided for this purpose.
[0041] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0042] Although the invention is illustrated and described herein as embodied in a induction cable, a coupling device, and a method for producing an induction cable, 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.
[0043] 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
[0044] FIG. 1 is a symbolic, side view of an induction cable according to the invention;
[0045] FIG. 2 is a cross-sectional view of the induction cable having a plurality of component cables;
[0046] FIG. 3 is a cross-sectional view of a component cable;
[0047] FIG. 4 is a plan view of a carrier, which is configured as a separator star, of a coupling module;
[0048] FIG. 5 is a cross-sectional view of a further variant embodiment of the carrier of a coupling module;
[0049] FIG. 6 is a schematic cross-sectional view of the coupling device having two coupling parts;
[0050] FIG. 7 is an illustration of a detail of a further exemplary embodiment of a coupling module; and
[0051] FIG. 8 is a highly simplified schematic illustration of receptacles, which are oriented in a connection direction, having conductor strands.
DETAILED DESCRIPTION OF THE INVENTION
[0052] In the figures, similarly acting parts are provided with the same reference symbols.
[0053] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown an induction cable 1 extending in a cable longitudinal direction 2 and has, in the exemplary embodiment, a plurality of coupling devices 3 at which individual partial cable pieces 4 are coupled to one another. The induction cable 1 usually has a large number of cable cores 6 . In this case, each individual cable core 6 is formed by a plurality of conductor sections 8 which are spaced apart from one another in the cable longitudinal direction 2 by insulating intermediate pieces 10 . The conductor sections 8 together with the insulating intermediate pieces 10 form a conductor strand 9 which is sheathed by an insulation 11 (compare, in particular, FIG. 6 in this respect) in order to form the cable core 6 . The insulation 11 is selectively a taping or else an, in particular extruded, insulation sheath. The intermediate pieces 10 are composed of a suitable insulation material, in particular of ceramic.
[0054] In this case, the conductor sections 8 have a contact spacing “a” typically in the region of several tens of meters, for example in the region of 50 m or a multiple thereof. The overall length of an induction cable 1 of this kind is usually several hundreds of meters, in particular in the region of a few kilometers, for example in the range of from 1 to 3 km. Induction cables 1 of this kind are laid in the ground in order to inductively heat oil sands. The induction cables are usually introduced into pipes for this purpose. The coupling devices 3 are at a distance of greater than the contact spacing “a”, in particular a multiple of the contact spacing “a”, in relation to one another.
[0055] At the same time, the intermediate pieces 10 define resonance separation points R which are arranged in the contact spacing “a”. The resonance separation points R of the various cable cores 6 are located at different longitudinal positions, wherein a plurality of the cable cores 6 are preferably combined to form groups, of which the resonance separation points R are located at an identical longitudinal position. In the exemplary embodiment, two groups of cable cores 6 are formed, the resonance separation points R of the groups being offset in relation to one another by half a contact spacing “a”.
[0056] In contrast, a respective coupling device 3 defines a coupling position K at which, therefore, a plurality of cable cores 6 are interrupted and connected by the coupling device 3 . Here, interrupted is intended to be understood to mean that the cable core 6 or the conductor strand 9 is not guided further without interruption, but rather is separated so as to form coupling ends 20 a, b (compare, for example, FIGS. 3 and 6 in this respect). The individual cable cores 6 typically have a diameter in the range of from, for example, 1.5 to 2.5 mm, wherein the conductor strand 9 has a diameter of typically 0.8 to 1.5 mm.
[0057] A preferred construction of an induction cable 1 of this kind is illustrated in FIG. 2 . According to FIG. 2 , the overall induction cable 1 is made up of a plurality of component cables 12 , wherein each component cable 12 in turn has a plurality of core bundles 14 which each have a strain-relief device 16 in the center. The individual core bundles 14 are a composite, in particular a braided composite, of a plurality of cable cores 6 which, in turn, are arranged around a central strand, in particular an optical waveguide 15 . In the exemplary embodiment, the core bundles 14 are braided in two layers around the optical waveguide 15 . Overall, six of these core bundles 14 are then arranged, in particular braided, around the strain-relief device 16 of the component cable 12 and form the component cable 12 . The component cable 12 preferably has a cable sheath 18 . The three component cables 12 are, in turn, usually braided with one another and likewise surrounded by a further cable sheath 18 .
[0058] FIG. 3 shows a cross section through one of the component cables 12 with the core bundle 14 braided around the strain-relief device 16 . In each of the core bundles 14 , the individual cable cores 16 are arranged, in particular braided, around the central optical waveguide 15 . In this case, FIG. 3 shows a section through the induction cable 1 at one of the resonance separation points R. The dark circles mark first coupling ends 20 a in the region of the resonance separation point R, that is to say in the region of the insulating intermediate pieces 10 , whereas the light circles show second coupling ends 20 b of the conductor sections 8 which are of continuous design or are then electrically contact-connected to one another by the coupling device 3 .
[0059] FIG. 4 illustrates a first variant embodiment of a coupling module 22 which is designed as a separator star. The coupling module contains an approximately star-shaped carrier 24 which has, corresponding to the positions of the first coupling ends 20 a , first receptacles 26 a in the form of passage holes which form first connections. The carrier 24 therefore has arms in which these first receptacles 26 a are made in the manner of passage bores. Recesses 28 , which are open radially to the outside, are formed between these arms. The continuous conductor sections 8 which are guided without interruption are inserted into these recesses 28 from the outside. In contrast, the first receptacles 26 a define the resonance separation point R with the insulating intermediate piece 10 .
[0060] Furthermore, a functional connection 30 is formed centrally in the carrier 24 , the functional connection being configured to guide and, in particular, to connect a central functional conductor, specifically the optical waveguide 15 . This functional connection 30 is configured, for example, in the manner of a plug connector for connecting two light guide ends or receives corresponding plug connection elements.
[0061] Whereas only a limited number of cable cores 6 are interrupted in the case of the separator star according to FIG. 4 , all of the cable cores 6 of the core bundle 14 are interrupted and connected to one another by the coupling module 22 in the case of coupling module 22 , as is illustrated in FIG. 5 . In FIG. 5 , the dark circles once again indicate the first coupling ends 20 a of the electrically conductively guided conductor sections 8 and the light circles once again indicate the second coupling ends 20 b at the resonance separation point R. In this respect, FIG. 5 therefore shows a cable end 32 within the meaning of the present application. Here, the light circles at the same time also define second receptacles 26 b in which the coupling ends 20 b are situated. These second receptacles 26 b are, in turn, formed by bushings through the carrier 24 . The carrier 24 is generally composed of an insulating material, in particular plastic, and is configured, for example, in an approximately plate-like or disk-like manner with only a small thickness in the cable longitudinal direction 2 .
[0062] In the present case, “cable” is generally intended to be understood to mean any common composite of cable cores 6 , in particular a braided composite. Therefore, the core bundle 14 forms a smallest cable unit. The next largest medium cable unit is formed by the component cable 12 , and the next largest cable unit in turn is finally formed by the entire induction cable 2 .
[0063] The different refinements of the coupling device 3 described here selectively relate to the smallest cable unit (core bundle 14 ), the medium cable unit (component cable 12 ) or the overall cable unit (inductor cable 2 ). The described construction of the coupling device 3 therefore serves selectively to connect the core bundle 14 , the component cable 12 or else the entire induction cable 1 .
[0064] A dedicated coupling device 3 is expediently provided for each component cable 12 , so that each component cable 12 can be independently separated. As an alternative, an overall coupling device 3 is also provided, it being possible for the induction cable 1 to be separated overall at a separation point by the overall coupling device.
[0065] A special variant embodiment of the coupling device 3 is illustrated in FIG. 6 . According to FIG. 6 , the coupling device 3 has two coupling parts 34 a , 34 b which each receive a carrier 24 and comprise housing parts 36 a , 36 b which can be connected to one another to form the coupling and therefore hold the carrier 24 and therefore also the individual coupling ends 20 a , 20 b in a defined relative position in relation to one another. The housing parts 36 a , 36 b are configured, in a manner not illustrated in detail here, as plug parts or else as parts which can be screwed, for example, so that the two coupling parts 34 a , 34 b are therefore fastened to one another by screw-connection in the manner of screw couplings or, for example, by latching, and the carriers 24 are offset in relation to one another.
[0066] In order to form the insulating intermediate pieces 10 , insulating sleeves 38 , in particular ceramic sleeves into which the first coupling ends 20 a are introduced, are formed in the exemplary embodiment. In the exemplary embodiment, a termination cap 40 , in particular which is composed of metal, is fitted, for example by welding, onto the end side of a respective coupling end. In addition, the free space between the cap 40 and the sleeve 38 is filled with a further insulation material, in particular a silicone gel 42 or else an adhesive. This provides good insulation of the first coupling ends 20 a in relation to one another and achieves a high degree of resistance to partial discharge. In contrast to this, plug connector elements are fitted in the case of the coupling ends 20 b of the conductor sections 8 , specifically a plug pin 44 on one side and a plug sleeve 46 on the other side. The plug connector elements serve to electrically conductively connect the second coupling ends 20 b . The plug connector elements are electrically conductively connected, for example by welding or else by a crimping process, to the respective second coupling end 20 b . The electrically conductive connection is automatically formed when the two coupling parts 34 a , 34 b are combined.
[0067] In the exemplary embodiment described in relation to FIG. 6 , the intermediate piece 10 is configured in a manner divided into two in as much as two insulating sleeves 38 are each fitted to the first coupling ends 20 a . There may further be an air gap between these sleeves 38 in the coupled state.
[0068] FIG. 7 illustrates an alternative refinement of a sleeve 38 , in which a double sleeve, in particular a ceramic sleeve, is situated in a respective first receptacle 26 a of the carrier 22 , it being possible for the coupling ends 20 a to be plugged into said double sleeve from both sides.
[0069] Finally, FIG. 8 shows a highly simplified illustration of another particular variant embodiment in which the receptacles 26 a , 26 b are oriented in a connection direction 50 at an angle in relation to the longitudinal direction 2 . In this case, the angle corresponds, in particular, to a pitch angle of the individual cable cores 6 which the individual cable cores assume as a result of being braided with one another. This ensures that the cable cores 6 are in alignment with the connections 26 a , 26 b , so that a simple plug-in operation is possible.
[0070] Particularly in the case of this variant embodiment, it is possible to also use a flat cable to form the induction cable 1 , in the case of the flat cable the individual conductor strands 9 each initially being arranged within a common plane in a common insulation sheath, and this ribbon cable then being wound around a central strand. Accordingly, it is also possible to provide a coupling device 3 for a ribbon cable of this kind which may be bent, the individual connections 26 a , 26 b being lined up next to one another in one row in the case of said coupling device.
[0071] Furthermore, a sensor module 52 is integrated into the coupling device 3 , both the induction cable 1 itself and also the environment, that is to say characteristic data about the induction field for example, being monitored by the sensor module and corresponding measurement data being passed on to an evaluation unit, not illustrated in any detail here. Parameters to be monitored are, for example, the cable temperature, the ambient temperature or else seismic movements etc.
[0072] The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:
1 Induction cable 2 Cable longitudinal direction 3 Coupling device 4 Partial cable piece 6 Cable core 8 Conductor section 9 Conductor strand 10 Intermediate piece 11 Insulation 12 Component cable 14 Core bundle 15 Optical waveguide 16 Strain-relief means 18 Cable sheath 20 a, b Coupling end 22 Coupling module 24 Carrier 26 a First connections 26 b Second connections 28 Recess 30 Functional connection 32 Cable end 34 a, b Coupling part 36 a, b Housing parts 38 Insulating sleeve 40 Cap 42 Silicone gel 44 Plug pin 46 Plug sleeve 50 Connection direction 52 Sensor module a Contact spacing R Resonance separation point K Coupling position | An induction cable contains a plurality of cable conductors each having a conductor strand surrounded by insulation. The conductor strand contains a plurality of conductor sections which are spaced apart in the longitudinal cable direction at resonance dividing points by insulating intermediate pieces. The induction cable furthermore has a coupling device on which a plurality of the conductor strands are separated forming coupling ends at coupling positions. The coupling ends are connected to each other via the coupling device. A simple providing and installing of the induction cable and a simple replacement of damaged cable parts is thus enabled. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims the benefit under 35 U.S.C. §120 as a continuation-in-part of presently pending U.S. patent application Ser. No. 12/605,136, entitled DEFINING ENFORCING AND GOVERNING PERFORMANCE GOALS OF A DISTRIBUTED CACHING INFRASTRUCTURE, filed on Oct. 23, 2009, the entire teachings of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to the field of cache management and more particularly to management of a distributed caching infrastructure.
[0004] 2. Description of the Related Art
[0005] In an efficient admissions control and capacity planning policy, minimal resources can be allocated automatically to satisfy the requirements of a specified service level agreement (SLA), leaving the remaining resources for later use. An SLA is an agreement between a computing service provider and a computing service consumer that specifies a minimum level of service to be provided by the service provider on behalf of the consumer. The typical SLA includes one or more network traffic terms that either limit the amount and type of resources that the subscribing customer can consume for a given rate, or guarantee the amount and quality of service (QoS) of resources that the provider will provide to the subscribing customer for a given rate.
[0006] For example, a subscribing consumer can agree to an SLA in which the consumer agrees to consume only a particular quantity of network bandwidth offered by the provider. Conversely, the SLA can require the provider to guarantee access to the subscribing consumer to at least a minimum amount of bandwidth. Also, the SLA can require the provider to provide a certain QoS over the provided minimum amount of bandwidth.
[0007] When considering the terms of an SLA, content and application hosts provision server resources for their subscribing customers, co-hosted server applications or services, according to the resource demands of the customers at their expected loads. Since outsourced hosting can be viewed as a competitive industry sector, content and application hosts must manage their resources efficiently. Logically, to ensure that the customers receive the promised level of service in the SLA, content and application hosts can be configured to survive a worst-case load. Yet, the worst-case approach can unnecessarily tax the resources of the content host or the application host as the case may be, even when those resources are not required to service a given load. Hence, rather than over-provisioning resources, efficient admission control and capacity planning policies can be designed merely to limit rather than eliminate the risk of meeting the worst-case demand.
[0008] While SLA management and enforcement has become part and parcel of ordinary application hosting relationships between consumer and host, Extreme Transaction Processing (XTP) provides new challenges in the use and enforcement of the SLA. XTP is a technology used by application hosts to handle exceptionally large numbers of concurrent requests. Serving such a large volume of concurrent requests can be made possible in XTP by distributing the load resulting from the concurrent requests on computer clusters or whole grid computing networks. Further, general XTP supporting architectures often rely upon aggressive caching across an n-Tier caching infrastructure (a multi-tiered cache structure), affinity routing (the intelligent routing of a request to business logic executing nearest to the requisite data consumed by the business logic), and decreasing data-access latency via the “MapReduce” framework commonly used to support distributed computing on large data sets on clusters of computers. Thus, effective management of the multi-tiered cache structure can be critical to meeting the obligations set forth under an SLA.
BRIEF SUMMARY OF THE INVENTION
[0009] Embodiments of the present invention address deficiencies of the art in respect to performance management in an n-Tier caching architecture and provide a novel and non-obvious method, system and computer program product for the dynamic structural management of an n-Tier distributed caching infrastructure. In an embodiment of the invention, a method of dynamic structural management of an n-Tier distributed caching infrastructure includes establishing a communicative connection to a plurality of cache servers arranged in respective tier nodes in an n-Tier cache, collecting performance metrics for each of the cache servers in the respective tier nodes of the n-Tier cache, identifying a characteristic of a specific cache resource in a corresponding one of the tier nodes of the n-Tier crossing a threshold, and dynamically structuring a set of cache resources including the specific cache resource to account for the identified characteristic.
[0010] In this regard, in one aspect of the embodiment, identifying a characteristic of a specific cache resource in a corresponding one of the tier nodes of the n-Tier crossing a threshold can include identifying a utilization disparity amongst children cache servers supporting different cache clients in a common set of cache clients and a common parent cache server, for example the underutilization of one of the cache servers. As such, caching support for the different cache clients of the common set of cache clients can be consolidated in the cache server demonstrating cache underutilization. In another aspect of the embodiment, identifying a characteristic of a specific cache resource in a corresponding one of the tier nodes of the n-Tier crossing a threshold can include identifying a set of geographically proximate cache devices supporting a cache server. In response, a partitioned cluster of the geographically proximate cache devices can be established, the cache devices individually caching data pertaining to a corresponding unique topic assigned by the cache server.
[0011] Additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The aspects of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0012] The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention. The embodiments illustrated herein are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown, wherein:
[0013] FIG. 1 is a pictorial illustration of a process for enforcing performance goals in an n-Tier distributed caching infrastructure;
[0014] FIG. 2 is a schematic illustration of a computer data processing system arranged with an n-Tier distributed caching infrastructure; and,
[0015] FIG. 3 is a block diagram illustrating a process for dynamic structural management of an n-Tier distributed caching infrastructure based upon cache server utilization.
[0016] FIG. 4 is a flow chart illustrating a process for dynamic structural management of an n-Tier distributed caching infrastructure based upon cache server utilization.
[0017] FIGS. 5A and 5B , taken together, are a block diagram illustrating a process for clustering of cache devices of an n-Tier distributed caching infrastructure based upon cache device geographic proximity.
[0018] FIG. 6 is a flow chart illustrating a process for clustering of cache devices of an n-Tier distributed caching infrastructure based upon cache device geographic proximity.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Embodiments of the present invention provide a method, system and computer program product for dynamic structural management of an n-Tier distributed caching infrastructure. In accordance with an embodiment of the present invention, characteristics of caching resources in an n-Tier distributed caching infrastructure can be analyzed. In response to detecting a threshold characteristic such as a particular degree of utilization or a particular proximity to other caching resources, the structure of the caching resources can be adapted according to the threshold characteristic.
[0020] For example, in response to detecting amongst a set of cache servers servicing common cache clients, underutilization of one of the cache servers in the set, another of the cache servers in the set can be consolidated with the underutilized one of the cache servers. As another example, in response to detecting a threshold geographic proximity between caching devices servicing a cache server in the n-Tier distributed caching infrastructure, a cluster can be established for the geographically proximate caching devices such that each of the caching devices performs caching for data for a corresponding topic and one of the caching devices acting as a master caching device can route caching requests to different slave ones of the caching devices in the cluster according to a topic for each of the requests.
[0021] In further illustration, FIG. 1 pictorially depicts a process for enforcing performance goals in an n-Tier distributed caching infrastructure. As shown in FIG. 1 , an n-Tier cache 110 can be configured to include multiple different tiers of server caches 110 A . . . 110 N−1 for data stored in a database 120 . Performance goals for the n-Tier cache 110 can be established within terms of one or more SLAs 130 . A cache performance monitor 140 can monitor the performance of the n-Tier cache 110 in the context, by way of example, of retrieval times for retrieval requests from the different server caches 110 A . . . 110 N−1 in the n-Tier cache 110 . When the measured performance is determined to likely cause a breach in one or more terms of an SLA 130 , cache policy enforcer 150 can apply corrective action to one or more of the server caches 110 A . . . 110 N−1, for instance by establishing server affinity for specified data or a specified query in respect to an offending one of the server caches 110 A . . . 110 N−1, by increasing the cache size of an offending one of the server caches 110 A . . . 110 N−1, by allocating additional CPU cycles to an offending one of the server caches 110 A . . . 110 N−1, or by directing a re-structuring of cache resources in the n-Tier cache 110 , to name only a few remedial measures.
[0022] In further illustration, FIG. 2 is a schematic illustration of a computer data processing system arranged with an n-Tier distributed caching infrastructure. The system can include an application server 230 with processor and memory hosting the execution of application logic 235 for use by coupled clients 210 over computer communications network 220 . A presentation server 240 , also with processor and memory, further can be provided, such as a Web server, to provide a user interface 245 for the application logic 235 to the coupled clients 210 so as to provide a mode of access by the coupled clients 210 to the application logic 235 executing in application server 230 . Finally, a database server 285 can be communicatively linked to the application server 230 such that data in a companion database 290 can be used and managed by the application logic 235 and accessed through the application logic 235 by the coupled clients 210 .
[0023] Notably, a cache server 250 can be disposed within the communicative path between the database server 285 and the application server 230 . The cache server 250 can provide caching services for data stored in the database 290 as requested by the application logic 235 executing in the application server 230 . Further, an n-Tier cache 255 can be managed by the cache server 250 so as to implement an n-Tier caching architecture for data within the database 290 utilized by the application logic 235 in servicing requests from the coupled clients 210 through the user interface 245 provided by the presentation server 240 .
[0024] In accordance with an embodiment of the present invention, a cache policy enforcement module 260 can be coupled to the cache server 250 . The cache policy enforcement module 260 can include computer usable program code loaded from a computer readable medium into the memory of the cache server 250 (or other coupled server) and executed by a processor of the cache server 250 (or other coupled server). The cache policy enforcement module 260 can include each of a cache monitor portion 265 , a policy enforcer portion 270 and a policy manager portion 275 . Further, the cache policy enforcement module 260 can be configured to access one or more SLAs 280 defining performance objectives for the n-Tier cache 255 .
[0025] The policy manager portion 275 can include a set of code instructions for execution by a processor for adding, modifying and deleting the performance objectives of the n-Tier cache 255 in order to meet the terms of one or more of the SLAs 280 . In this regard, the code instructions of the policy manager portion 275 can provide access by an administrator to establish specific performance objectives of the cache servers of the n-Tier cache 255 such as response time expected of a given cache server in the n-Tier cache 255 .
[0026] The cache monitor portion 265 , in turn, can include a set of code instructions for execution by a processor for monitoring the performance of each of the cache servers in the n-Tier cache 255 such as response time for each of the cache servers or a utilization of different cache servers in serving different cache clients. Finally, the policy enforcer portion 270 can include a set of code instructions for execution by a processor for applying remedial measures to an offending one of the cache servers in the n-Tier cache 255 when the offending one of the cache servers in the n-Tier cache 255 is determined to have demonstrated observed performance falling short of the performance objectives specified by the policy manager portion 275 and likely to result in a breach of one or more of the terms of the SLAs 280 .
[0027] Of note, part and parcel of the effective management of the n-Tier cache 255 can include the dynamic restructuring of cache resources in response to detecting threshold characteristics of different cache resources of the n-Tier cache 255 as reported by the cache monitor portion 265 . In yet further illustration, FIG. 3 is a block diagram illustrating a process for dynamic structural management of an n-Tier distributed caching infrastructure based upon cache server utilization. As shown in FIG. 3 , different application consuming clients 310 can receive caching services from multiple different caching clients 320 —namely different computing applications utilizing the caching services of the cache servers 330 B, 330 C in distributing data to the application consuming clients 310 . The cache servers 330 B, 330 C can be the hierarchical children of cache server 33 A operating in application server 340 in an n-Tier cache.
[0028] Dynamic distributed cache hierarchy management logic 400 can interact with the cache server 330 A to detect utilization rates of both cache servers 330 B, 330 C servicing the same set of cache clients 320 —namely the cache server 330 B servicing cache clients 320 A, 320 B and cache server 330 C servicing cache clients 320 C, 320 D. When the utilization of one of the cache servers 330 C is determined to be underutilized beyond a threshold utilization, the logic 400 can direct the consolidation of the cache servers 330 B, 330 C so that the cache server 330 C services the cache clients 320 A, 320 B, 320 C, 320 D. Conversely, when the utilization of one of the cache servers 330 C is determined to be overutilized beyond a threshold utilization, the logic 400 can direct the separation of caching responsibilities from the cache server 330 C so that the cache server 330 C services the cache clients 320 C, 320 D and the cache server 330 B services cache clients 320 A, 320 B.
[0029] In illustration of the operation of the logic 400 , FIG. 4 is a flow chart illustrating a process for dynamic structural management of an n-Tier distributed caching infrastructure based upon cache server utilization. Beginning in block 410 , the cache server children of a cache server can be monitored for utilization. Additionally, in block 420 , common cache clients of the cache server children can be identified. In block 430 , a utilization disparity—for instance an underutilization condition—can be identified in one of the cache server children sharing common caching clients with another of the cache server children. In response, in block 440 , the caching responsibility for the caching clients can be consolidated into a single one of the cache server children sharing the common caching clients.
[0030] In addition to responding to threshold utilization of cache server children sharing common caching clients, the dynamic distributed cache hierarchy management can respond to cache devices managed by cache servers that are detected to have been positioned with geographic proximity. In even yet further illustration, FIGS. 5A and 5B , taken together, are a block diagram illustrating a process for clustering of cache devices of an n-Tier distributed caching infrastructure based upon cache device geographic proximity. As shown in FIG. 5A , different cache clients 510 can access cached data within cache devices 520 A, 520 B, 520 C managed by cache server 530 operating in application server 540 .
[0031] The dynamic distributed cache hierarchy management logic 300 can detect that the cache devices 520 A, 520 B, 520 C have been positioned within geographic proximity to one another—for example within a common data center. In response, as shown in FIG. 5B , the cache devices 520 A, 520 B, 520 C can be defined as a cluster 530 of partitioned caches. One of the cache devices 520 B can be assigned the status as a master cache device 550 and the remaining cache devices 520 A, 520 C can be assigned the status as slave devices 560 .
[0032] The dynamic distributed cache hierarchy management logic 700 can establish different topics for data serviced by the cache server 530 and the master device 550 can assign one or more of the topics to each different slave device 560 . For example, the master device 550 can maintain a routing table of topics and associated slave devices 560 and the master device 550 can distribute the routing table to the slave devices 560 . Once assigned a topic, the slave device 560 can listen for cache requests pertaining to the topic and can respond to corresponding cache requests accordingly.
[0033] Optionally, each of the cache devices 520 A, 520 B, 520 C can be designated a server or a client. As a client, a cache device 520 A, 520 B, 520 C merely listens for cache updates for an associated topic or topics as assigned by the master 550 . As a server, however, a cache device 520 A, 520 B, 520 C can both listen for cache updates for an associated topic and also can serve to other peer ones of the cache devices 520 A, 520 B, 520 C cache updates for other topics. In this way, when the cache server 530 becomes overutilized, the cache server 530 can designate a server one of the cache devices 520 A, 520 B, 520 C as a cache server 530 to manage cache updates for a selection of topics.
[0034] Referring now to FIG. 6 , a flow chart has been illustrated to show a process for clustering of cache devices of an n-Tier distributed caching infrastructure based upon cache device geographic proximity. Beginning in block 610 , different cache devices supporting a cache server in an n-Tier cache can be scanned and in block 620 , the geographic location of each scanned cache device can be determined. In decision block 630 , it can be determined if the scanned cache devices are geographically proximate to one another within a threshold distance. If so, in block 640 a partitioned set of caches can be arranged with the scanned cache devices.
[0035] In block 650 , one of the scanned cache devices in the partitioned set can be designated a master device and the remaining cache devices can be designated slave devices. In block 660 , a routing table can be established in the master cache device and the cache server can be directed to establish different topics for cache updates for inclusion in the routing table. In block 680 , the routing table can be provided to the different slave devices to indicate which topic or topics are to be associated with each slave device. Finally, in block 690 the process can end. In this way, the geographically proximate cache devices can be dynamically structured into an arrangement of cache devices efficiently servicing only a subset of cache updates pertaining to specifically assigned topics in order to improve the performance of the n-Tier cache.
[0036] Embodiments of the invention can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, and the like. Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system.
[0037] For the purposes of this description, a computer-usable or computer readable medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device). Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk—read only memory (CD-ROM), compact disk—read/write (CD-R/W) and DVD.
[0038] A data processing system suitable for storing and/or executing program code will include at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution. Input/output or I/O devices (including but not limited to keyboards, displays, pointing devices, etc.) can be coupled to the system either directly or through intervening I/O controllers. Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters. | Embodiments of the present invention provide a method, system and computer program product for the dynamic structural management of an n-Tier distributed caching infrastructure. In an embodiment of the invention, a method of dynamic structural management of an n-Tier distributed caching infrastructure includes establishing a communicative connection to a plurality of cache servers arranged in respective tier nodes in an n-Tier cache, collecting performance metrics for each of the cache servers in the respective tier nodes of the n-Tier cache, identifying a characteristic of a specific cache resource in a corresponding one of the tier nodes of the n-Tier crossing a threshold, and dynamically structuring a set of cache resources including the specific cache resource to account for the identified characteristic. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application No. 61/665,963, filed Jun. 29, 2012, and entitled “Improved Low-Profile Drying Rack,” the entire contents of which is incorporated herein by reference.
FIELD OF THE DISCLOSURE
The present disclosure relates to devices for drying assorted items and more particularly to passive drying devices for assorted items.
BACKGROUND
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Laundering of clothing and other articles is a frequent, recurring chore in many households. Free standing drying racks are often used to dry clothing after it has been washed or where an item gets wet and an individual wishes to dry the item quickly, but without using an electric or gas dryer. Use of conventional, free-standing drying racks requires time consuming setup before drying can begin, involving the impairment of valuable floor space in the home while the rack is in use, and requiring another round of time consuming break down and storage after drying has been completed. This process then requires repeating the next time the laundry is washed. These shortcomings are exacerbated when considering that many people must do laundry in tight living quarters, such as dormitories, barracks, shared housing, small urban apartments, and the like.
Further, conventional, portable, free standing racks also present potential dangers to pets, children, and adults alike because the unsecured rack can easily be knocked over. Other drying racks are designed to be mounted on the wall. Some wall mounted drying racks tend to protrude a significant amount from the wall, creating a safety hazard.
Given the foregoing, what is needed are improved low-profile drying devices capable of being used and stored in tight living quarters.
SUMMARY
This Summary is 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 subject matter, nor is it intended to be used to limit the scope of the subject matter.
This disclosure addresses the above-described needs by providing devices configured to facilitate the air drying of assorted items. Assorted items include, but are not limited to, laundry of all shapes, sizes, and types.
Aspects of the present disclosure provide a device configured to facilitate air drying assorted items, such as laundry, without taking up significant floor or wall space. Devices configured in accordance with an aspect of the present disclosure are small, compact racks that can be secured to the front or back of a door or can be removably mounted to a wall and can be easily folded down for use. Products according to the present disclosure are ideal for laundry rooms or other small areas that may not have adequate floor or wall space for traditional drying racks. They may also eliminate the need to use an (electric) dryer, thereby saving energy and reducing utility bills.
In an aspect, a drying device is configured to conserve space both when in and out of use by being removably mounted on a standard interior door or wall. At least one hook is placed over the top of the interior door which supports the weight of the drying device and any objects placed on the drying device. A rigid frame is attached to the hooks and one or more drying arms are moveably attached to the rigid frame. When in use, at least one of the drying arms is placed in its drying position by rotating the arm into a position approximately perpendicular to the rigid frame. Objects to be air dried are placed on the extended drying arm to dry. When the device is not in use, it is configured to be left on the door, protruding mere inches. In some aspects where the device is not in use, the device is additionally or alternatively configured to be removed from the interior door and folded into a compact form for storage. Such a configuration eliminates the conventional cumbersome drying racks that utilize living areas and obstruct walkways. Some aspects do not require permanent mounting to install on a door.
Some aspects of the disclosed drying device are configured to dry the equivalent of 22 linear feet of laundry at one time. Other aspects are configured to dry higher volumes of laundry simultaneously.
Further features and advantages of the systems and apparatus disclosed herein, as well as the structure and operation of various aspects of the present disclosure, are described in detail below with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present disclosure will become more apparent from the Detailed Description set forth below when taken in conjunction with the drawings in which like reference numbers indicate identical or functionally similar elements.
FIG. 1 is an illustration of a three-quarters view of the front of an exemplary drying device wherein the device's drying arms are in the drying position, in accordance with an aspect of the present disclosure.
FIG. 2 is a detailed illustration of the front of an exemplary drying arm locking mechanism, in accordance with an aspect of the present disclosure.
FIG. 3 is an illustration of a front view of an exemplary drying device wherein the device's drying arms are in the stored position, in accordance with an aspect of the present disclosure.
FIG. 4 is an illustration of a three-quarters view of the front of an exemplary drying device wherein the device's drying arms are in the stored position, in accordance with an aspect of the present disclosure.
FIG. 5 is an illustration of a perspective view of the back of an exemplary drying device wherein the device's drying arms are in the stored position, in accordance with an aspect of the present disclosure.
FIG. 6 is an illustration of a perspective view of an exemplary drying device wherein the device is folded for storage, in accordance with an aspect of the present disclosure.
DETAILED DESCRIPTION
The present disclosure is directed to devices configured to facilitate the air drying of assorted items. Assorted items include, but are not limited to, laundry of all shapes, sizes, and types. In some aspects, devices configured in accordance with the present disclosure are adapted to assist air-drying laundry of all shapes, sizes, and types. Specifically, aspects in accordance with the present disclosure are suitable for facilitating the drying of clothing, linens, and sheets of fabric.
In an aspect, a drying device comprises a frame and one or more drying arms. The drying device is configured to hang from two hooks attached to a frame top portion of the drying device. The drying device is deployed by placing hooks over the top of a vertical surface such as a door, fence, or wall. One or more drying arms are rotatably connected to frame and configured to rotate into a drying position which is perpendicular to frame and vertical surface. Miscellaneous objects are placed on the extended drying arm to dry. Drying is facilitated by spacing assorted items on the drying arms such that substantially all of the surface area of the assorted items is exposed to the surrounding air.
In some aspects when the drying device is not in use, it is configured to be left on the vertical surface, protruding a distance on the order of frame depth. Drying arms are rotated into storage position substantially in parallel with the drying device frame. In some aspects where the drying device is not in use, the device is additionally or alternatively configured to be removed from the interior door and folded into a compact form for storage.
Referring to FIG. 1 , an illustration 100 of a three-quarters view of the front of an exemplary drying device 101 wherein the device's drying arms are in the drying position, in accordance with an aspect of the present disclosure, is shown.
Drying device 101 comprises a frame 104 and one or more drying arms 110 (shown as drying arms 110 a - d in FIG. 1 ). Frame 104 is a rigid support structure configured to orient drying device 101 on a vertical surface 102 such as a as a door, fence, or wall and support the weight of drying device 101 and assorted items placed thereon. Frame 104 is constructed of one or more sturdy materials such as plastic, metal, or wood. In some aspects, frame 104 material may be configured to be lightweight, enabling drying device 101 to be easily set up and removed each time it is used to dry assorted items. In an aspect, the material chosen for frame 104 is used throughout the rest of drying device 101 , facilitating ease of manufacture.
In an aspect, frame 104 comprises one or more cross members 106 (shown, for clarity, only as cross members 106 a - b in FIG. 1 ) and one or more vertical members 108 (shown as vertical members 108 a - b in FIG. 1 ). In an aspect, vertical member 108 defines the overall length of drying device 101 . The length of vertical member 108 is chosen such that drying device 101 may be mounted on a vertical surface 102 , such as an interior door. In an aspect, vertical member 108 is five feet, eight inches long; one foot shorter than the height of a standard interior door (six feet, eight inches). Two vertical members 108 are horizontally positioned two feet apart and rigidly connected by five cross members 106 spaced at equal intervals along the length of vertical members 108 .
In an aspect, cross members 106 are rigidly connected to vertical members 108 at end portions of cross member 106 . Rigid connection may be made by a fastener, adhesive, screw, dowel rod, or other connection means as will be appreciated to those having skill in the relevant art(s) after reading the description herein. The rigid connection may be permanent, as in the case of utilizing an adhesive. In other aspects, the rigid connection is removable, as in the case of utilizing a fastener or screw connection.
In an aspect, frame 104 is constructed of one-inch bars. These bars may be made of wood or some other suitable sturdy material. In another aspect, frame 104 further comprises a non-skid backing on portions of frame 104 configured to contact vertical surface 102 . Non-skid backing may be a rubber coating or cloth layer. The non-skid backing provides additional stability by inhibiting movement of frame 104 relative to vertical surface 102 .
In an aspect, the length of frame 104 is adjustable. Frame 104 is comprised of two vertical members 108 , horizontally positioned a distance less than an interior door apart and rigidly connected by five cross members 106 spaced at equal intervals along the length of vertical members 108 . Vertical members 108 comprise four sections of equal length which are removably and rigidly interconnected. One or more vertical member 108 sections may be removed in order to reduce the length of frame 104 . For example, removing one section from each vertical member 108 will reduce the length of frame 104 by one quarter. Reduction of the size of frame 104 allows drying device 101 to be used in more confined areas and facilitates its stability in confined areas.
Drying arm 110 comprises one or more drying areas 112 (shown, for clarity, only as drying area 112 b in FIG. 1 ) and one or more connectors 114 (shown, for clarity, only as connections 114 c - d in FIG. 1 ). Drying area 112 is configured to support assorted items during drying. In an aspect, drying area 112 has dimensions of approximately two feet by one and a half feet. Drying area 112 comprises three drying bars with a length of approximately two feet positioned in parallel with cross members 106 and two supports with length of approximately one and a half feet positioned in parallel with vertical member 108 . Each support is rotatably connected to frame 104 on one end portion by connector 114 . As will be appreciated by those skilled in the relevant art(s) after reading the description herein, connector 114 may be a bearing, an axle, pin or other suitable connection.
Supports are connected to one another via drying bars. The first drying bar is rigidly connected at each end portion to end portions of each support. The second drying bar is connected at each end portion to each support, approximately six inches away from the connection points of the first drying bar. The third drying bar is connected at each end portion to each support and positioned approximately six inches away from the connection points of the second drying bar and approximately twelve inches away from the first drying bar. Assorted items may be placed on drying area 112 b of drying arm 110 b in order to facilitate air drying. In some aspects, drying bars are round in order to prevent creasing the assorted items placed on the drying bars. In some aspects, drying device 101 may comprise multiple drying arms 110 .
In an aspect, drying area 112 has dimensions of approximately two feet by one and a half feet. Drying area 112 comprises two supports with length of approximately one and a half feet positioned in parallel with vertical member 108 and a lattice stretched between the two supports and configured to support small assorted items while they dry and to allow air to pass through the lattice. In an aspect, the lattice is comprised of a cloth, plastic, or metal mesh. In another aspect, the lattice is a framework of closely-spaced, interconnecting rods.
In some aspects, drying rack 110 is connected to frame 104 via connection 114 , and connection 114 is positioned directly above cross member 106 . Drying arm 110 may be placed in two positions: a stored position (depicted in FIGS. 3 and 4 ) wherein drying arm 110 is parallel to frame 104 , and a drying position wherein drying arm 110 is perpendicular to frame 104 . In an aspect, drying arm 110 is supported while in the drying position by cross member 106 positioned directed below connection 114 . Cross member 106 is rigidly connected to vertical member 108 and positioned to protrude one inch from vertical member 108 . When drying arm 110 is in the drying position, drying arm 110 is in contact with the top portion of cross member 106 , which supports drying arm 110 and any items placed thereon. Drying arm 110 is held in the stored position by one or more retainers 116 (shown, for clarity, only as retainer 116 a in FIG. 1 ). Retainer 116 may be any device configured to removably hold drying arm 110 in a static, stored position.
Now referring to FIG. 2 , a detailed illustration 200 of the front of an exemplary drying arm retainer 116 , in accordance with an aspect of the present disclosure, is shown. In an aspect, retainer 116 comprises a cylindrical, rigid pin 202 configured to be removably inserted in a first cylindrical hole 204 in vertical member 108 b and pass through a second cylindrical hole 206 in a portion of drying arm 110 when drying arm 110 is in the drying position. The second cylindrical hole 206 is positioned such that it aligns with the first cylindrical hole 204 when drying arm 110 is in the stored position (i.e., parallel to frame 104 ). Such a position is the lock position of drying arm retainer 116 . When drying arm retainer 116 is not engaged with drying arm 110 , drying arm retainer 116 is in a release position.
Referring now to FIGS. 3 and 4 , an illustration 300 of a front view and an illustration 400 of a three-quarters view of the front of an exemplary drying device 101 wherein its drying arms 110 are in the stored position, in accordance with aspects of the present disclosure, are shown.
Illustration 300 depicts drying arms 110 (shown as drying arms 110 a - d in FIGS. 3 and 4 ) in their stored position (i.e., parallel to frame 104 ). Illustration 300 depicts the low profile of drying device 101 when drying arms 110 are in their stored positions. Drying device 101 is mounted to vertical surface 102 via one or more hooks 302 (shown as hooks 302 a - b in FIG. 3 ) rigidly mounted to frame 104 . Each hook 302 is a device configured to hang drying device 101 and assorted items placed on drying device 101 from vertical surface 102 . In an aspect, hooks 302 comprise rigid portions of metal connected on one end portion to frame 104 and bent into a “U” or other shape suitable for hanging over the top portion of a door.
Referring now to FIG. 5 , an illustration 500 of a perspective view of the back of an exemplary drying device 101 wherein the device's drying arms 110 are in the stored position, in accordance with an aspect of the present disclosure, is shown.
In some aspects, drying device 101 is configured to be removably mounted to a vertical surface 102 such as a door, fence, or wall. Mounting is facilitated by one or more brackets 502 (for clarity, shown only as brackets 502 a - b in FIG. 5 ). Bracket 502 is rigidly connected to drying device 101 on frame 104 and is configured to support the weight of the drying device 101 and any objects placed on the drying device 101 when placed on the vertical surface. In some aspects, brackets 502 support drying device 101 by removably attaching to a screw, nail, or other mounting member placed in the vertical surface 102 . In an aspect, hook 302 is removable, allowing drying device 101 to be mounted on a door or a wall, depending on configuration.
In some aspects, drying device 101 is configured to be removably connected to vertical surface 102 and stored when it is not in use. In an aspect, vertical member 108 comprises two rigid bars connected together via one or more hinges 504 (shown as hinges 504 a - b in FIG. 5 ). Vertical member 108 is configured such that frame 104 may be folded in half via hinges 504 when drying device 101 is not in use. As shown in illustration 600 of FIG. 6 , drying device 101 occupies a volume with a similar width, half the height, and twice the thickness when it is not in use.
In other aspects, drying device 101 is configured to be separated into one or more portions for storage when not in use. In an aspect, drying arms 110 are rotatably connected to portions of frame 104 . Frame 104 is divided into sections corresponding with drying arms 110 . Each frame 104 section is removably connected to one or more frame sections via connection means such as locking pins and bolts. In other aspects, frame 104 sections are screwed together at end portions, enabling them to be rigidly connected and removably connected.
While various aspects of the present disclosure have been described above, it should be understood that they have been presented by way of example and not limitation. It will be apparent to persons skilled in the relevant art(s) that various changes in form and detail can be made therein without departing from the spirit and scope of the present disclosure. Thus, the present disclosure should not be limited by any of the above described exemplary aspects.
In addition, it should be understood that the figures in the attachments, which highlight the structure, methodology, functionality and advantages of the present disclosure, are presented for example purposes only. The present disclosure is sufficiently flexible and configurable, such that it may be implemented in ways other than that shown in the accompanying figures.
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 relevant art(s) who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of this technical disclosure. The Abstract is not intended to be limiting as to the scope of the present disclosure in any way. | Drying devices facilitating air drying of assorted items without taking up significant floor space are disclosed. In an aspect, a drying device includes a frame mountable to a vertical surface such as a door, wall, or fence. The drying device includes a plurality of drying areas which may be moved between a stored position and a drying position. In the stored position, the drying device has a compact profile, thereby occupying very little space when not in use. In the drying position, the drying areas extend away from the frame and may support articles, such as clothing, as the articles dry. | 3 |
BACKGROUND OF THE INVENTION
This invention relates, in general, to apparatus for cell transplantation technology, and, in particular, to apparatus for islet cell transplantation for the cure of Diabetes Mellitus
DESCRIPTION OF THE PRIOR ART
In the prior art various types of instruments for cell isolation have been proposed. For example, U.S. Pat. No. 5,079,160 discloses a method of obtaining purified, well-defined cell population from intact organs which uses the digestion of the distended organ with suitable proteolytic enzymes and harvest of the cell subpopulation by screening the effluent from the treatment of the organ with physiologically compatible medium by a filtration screen which permits the passage of the desired cells, but prevents the passage of large particles.
U.S. Pat. No. 5,447,863 discloses a method and apparatus to concentrate and purify islets of Langerhans from a tissue suspension containing islets and tissue fragments. The tissue suspension is flowed through an inclined channel such that laminar flow is established. The islets settle toward the bottom and are drawn out.
U.S. Pat. No. 5,322,790 discloses a method of producing intact islets of Langerhans using a mixture of Hank's solution and 10% by volume fetal calf serum to ductally distend the human pancreas. The exocrine tissue of the pancreas is digested at about 37° C. by an enzyme preparation of collagenase, trypsin and proteolytic enzyme preset in the mixture at a level of about 0.2% by weight.
U.S. Pat. No. 4,868,121 discloses a method of producing intact islets of Langerhans using a mixture of Hank's solution and 10% by volume fetal calf serum to ductally distend the human pancreas. The exocrine tissue of the pancreas is digested at about 37° C. by an enzyme preparation of collagenase, trypsin and proteolytic enzyme preset in the mixture at a level of about 0.2% by weight. The digested pancreas is comminuted, filtered and intact islets are recovered.
As shown by the above cited prior art patents, islet cell transplantation has evolved over the last decade. This technology is a conceptual advance over organ transplantation and can replace pancreas transplantation, thereby eliminating many of the drawbacks and side effects of pancreas transplantation.
In a pancreas transplant a donor pancreas is obtained and directly transplanted into a patient. Infection and the risk of rejection is always present in such an operation. However, in islet cell transplantation the objective is to transplant live, viable islet cells and discard 99% of the exocrine pancreas which is useless. In such a procedure, the dangers associated with a pancreas transplant are virtually eliminated. In islet cell transplantation the pancreas is processed in a laboratory to liberate and purify the islet cells. The cells are then encapsulated to prevent destruction by the host immune attacks (immunoisolation) and then transplanted into a patient. Islet cell transplantation has been hailed as a cure for Diabetes Mellitus
This is a disease that affects more than 3% of the world population and is a major public health problem. It is associated with an increase in renal failure, blindness, heart attacks, strokes, hypertension and amputations. In a 1992 study, it was noted that 3% of the diabetic patients accounted for 15% of the health care costs, and amounted to a staggering 100 billion dollars. These high costs indicate a failure, using conventional approaches, to control blood sugar levels in patients and to cure the underlying disease and the morbidity associated with this disease.
The most widely used approach to isolate islet cells is the method and apparatus disclosed in the Lacey et al patent, (U.S. Pat. No. 5,079,160). In pancreas transplantation the cure of type 1 diabetes is feasible with 1/2 to 1 pancreas while the transplantation of islet cells using known technology requires as many as 8 pancreas. Thus there is an increase of up to 16 fold in the number of pancreas needed to realize a sufficient supply of islets. Clearly major improvements are needed in the current methods of islet cell isolation procedures.
SUMMARY OF THE INVENTION
The present invention utilizes the basic concept of filtration. A dual channeled vacuum-pressure pump is used across two chambers to generate a continuous circulation of fluid. The first chamber is used to digest collagenase distended pancreas at 37° C., while the second chamber is used to concentrate and purify the islet cells at 4° C. The following additional improvements are incorporated to reduce bioburden, improve immunoprotection of viable cells and to automate laboratory components of islet cell transplantation.
1) Use of a dry incubator to reduce water contamination risk.
2) Eliminating the need for mechanical shaking to reduce airborne contamination.
3) The use of aseptic vacutainer port for aseptic sample aspiration for various studies and to reduce the risk of infection.
4) The use of a Leuco-absorb filter to remove passenger leucocytes, thereby reducing immunogenicity and the risk of infection from leucotrophic viruses.
5) The use of A/G technology hollow fibers without macrovoids to improve tensile strength and reduce the risk of breakage of the hollow fibers.
6) The use of Na Aliginate with high `G` content to immunoisolate islet cells and to reduce the risk of fibrosis of hollow fibers after being implanted.
7) The use of gentle, atraumatic cell separation technique such as velocity sedimentation at unit gravity to purify islet cells in the cell collection chamber. This allows further automation and integration of organ digestion, cell separation and purification. Purified islet cells can be conveniently syringe extruded and gelled inside hollow fibers, either manually or by an automated approach.
It is an object of the present invention to provide an improved apparatus for islet cell transplantation that is cost effective and clinically safe to use.
It is an object of the present invention to provide improved apparatus for islet cell transplantation that obviates the problems associated with the prior art apparatus.
These and other objects and advantages of the present invention will be fully apparent from the following description, when taken in connection with the annexed drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective, exploded view showing the digestion and cell collection chambers of the present invention.
FIG. 2 is a schematic view of the present invention showing a three step approach to automate and integrate various laboratory components of islet cell transplantation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in greater detail, FIG. 1 shows an exploded view of the digestion chamber 1 of the present invention. The digestion chamber 1 is essentially the same as the cell collection chamber, except as noted below, and therefore, a view of one chamber will show all the essential details of both chambers. The digestion chamber has a container 1 which is preferably made of clear, biocompatible polysulfone material, and is autoclavable and reusable. The chamber size is approximately 500 ml and has graduations 11 along the side.
A cover 2 is attached to the top of the chamber, for example by screw threads (not shown) and is sealed by means of a conventional 0-ring 3. The cover 2 has three ports 4, for a purpose to be described below. The bottom of the chamber 1 is open and has a bottom cover 5. It should be noted that the bottom cover is shown as attached to the bottom of the chamber and the 0-rings 6, the filter 7 and the support plate 8 for the filter are shown outside the bottom cover 5 only for illustration purposes. Actually, the O-rings 6, the filter 7 and the support plate 8 for the filter are inside the bottom cover which holds the various elements in place and also secures the funnel 9. Attached to the bottom of the funnel 9, by any conventional means is a vacuum adaptor 10 which secures the funnel to the tubing 12, as shown in FIG. 2.
Referring now to FIG. 2, the positioning and connection of the digestion and cell collection chambers 1 and 29 are shown. The two chambers on the top are connected by neoprene tubing 32 connected to respective ports 4 and 4a. A leukocyte filter 31 and a sampling port 30 are interposed between the connections to the chambers 1 and 29. The bottom of the chamber 1 is connected through the funnel 9 to approximately four feet of neoprene tubing 12, to the outlet port 13 of vacuum pressure pump 15. The inlet port 14 of the pump 15 is connected to approximately three feet of neoprene tubing 16. The other end of this tubing is attached to port 17 of the aspiration-collection bottle 18. The aspiration-collection bottle 18 is housed inside a dry incubator 19 at a temperature of 37° C. The port 20 of the aspiration-collection bottle 18 is connected to approximately three feet of neoprene tubing 21. The other end of this tubing is connected to outlet port 22 of the vacuum-pressure pump 15. The inlet port 23 of the vacuum-pressure pump 15 is connected to four feet of neoprene tubing 24. The other end of this tubing is connected to the arm of inverted "Y" adapter 26. Claps 25a and 25b are interposed below "Y" adapter 26 to regulate fluid flow.
Element 27 is a screening filter placed in the bottom of chamber 29 to permit the collection of islet cells between 50-450 micron size and pass cell debris less than 50 micron size. Collected islet cells are cooled to 4° C. by an ice bag containing device 28.
The other arm of the inverted "Y" adapter 26 is connected to tubing 35. Element 34 is a variable speed peristaltic pump that regulates the flow of density media to the chamber 29. Density gradient apparatus 36 and 37 are placed on the magnetic stirrer 38.
Inside chamber 29 is a cell aspiration tubing 39. Cells are aspirated by the variable speed peristaltic pump 40 and transported via three way valve 41 to a 50 ml syringe 42. The cells are mixed with Na alginate present in the syringe and extruded into the lumen of the hollow fiber housed in immunoisolation chamber 43. Element 46 is an aspiration bottle containing Cacl 2 which is aspirated by way of tubing 45 into immunoisolation chamber 43.
The apparatus shown in FIG. 2 is assembled after being sterilized and primed. The top cover 2a of the cell collection chamber 29 is removed and the chamber is filled with 500 ml of Hank's balanced solution. Then the aspiration-collection bottle 18, of 1-2 liter capacity, is filled with Hank's balanced solution. The funnel 9 at the bottom of the digestion chamber 1 is detached from the adapter 10 and is directed to a waste container (not shown) and the vacuum-pressure pump 15 is started. This causes negative suction in cell collection chamber 29, drawing Hank's solution from the chamber 29, across the filter 27 into the aspiration-collection bottle 18.
The fluid is warmed to 37° C. by an incubator 19. The fluid from the aspiration-collection bottle 18 exits through tubing connection 17. A positive pressure is exerted to drive fluid through the adapter 10. Approximately 10-20 ml of Hank's solution is allowed to drip out, then the funnel 9 is reattached to the adapter 10. Hank's solution will enter the chamber 1 through positive pressure from the pump 15. At this point the pump is stopped. The temperature of the Hank's solution is allowed to reach 37° C.
Collagenase distended pancreas is then loaded into chamber 1 from the top, and the top cover 2 is secured tightly. The vacuum-pressure pump 15 is started and positive pressure is exerted in chamber 1, and simultaneously negative pressure is exerted in chamber 29. This causes the fluid to circulate between chamber 29, aspiration-collection bottle 18, and chamber 1 where the fluid enters at 37° C.
Once the chamber 1 is filled, the fluid will move from chamber 1 to chamber 29 across the tubing 32 which bridges both chambers through ports 4 and 4a. A continuous recirculation of fluid is thus established. As the collagenase distended pancreas in chamber 1 is digested at 37° C., liberated cells will flow through port 4 into tubing 32. Wandering leucocytes are adsorbed in the leucoabsorb filter 31 and remaining cells enter chamber 29.
Intermittent samples of cells and fluid can be obtained through vacutainer port 30 for various studies. Cells exiting chamber 29 get deposited on filter 27, whose filter pore size is 50 microns. This allows islet cell of 50-450 micron size to be deposited on top of the filter. Smaller size cells and debris pass through filter 27 and are deposited in the aspiration-collection bottle 18. Reentry of debris into chamber 1 is blocked by interposing filters of 0.2 and 10 micron pore size between chamber 1 and tubing 17.
Once digestion is complete (approximately 30-45 minutes), the vacuum-pressure pump is turned off. The draining of fluid from chamber 29 to aspiration-collection bottle 18 is blocked by clamp 25a. Cells collected by filter 27 in chamber 29 are further purified without manually handling in any conventional manner. Peristaltic pump 34 is then started and clamp 25b is opened. This will draw density media solution from density gradient maker apparatus 36-37. The fluid will bottom lift cells deposited on filter 27 into chamber 29.
Then the pump is stopped, the top 2a of chamber 29 is opened and five glass balls are gently placed inside. The balls are of different colors, light weight and sterile. They are custom designed and calibrated at 20° C. to have a known density weight of 1.000, 1.050, 1.100, 1.150, and 1.200, respectively. Most islet cells will have a density in the range of 1.050 to 1.100. The cells are allowed to settle according to their size and density. This will take three to four hours. At this time a conventional transfer pipette (not shown) is introduced through port 4a to aspirate cell samples from different depths. The glass balls are used to monitor density and cell location.
Cell samples are stained with Dithiozone (DTZ) stain and examined under a light microscope (not shown) to help identify islet cells (stained dark brown). Once a desired cell band is identified, the tubing 39 is lowered to the desired depth as indicated by the glass balls. Cells are then aspirated by peristaltic pump 40. The cells are mixed in the 50 ml syringe 42 containing Na alginate solution with a high `G` content. Cells are manually syringe extruded through 3-way adapter valve 41 into the A/G technology hollow fiber lumen 44.
The hollow fiber has a membrane which is cut off at 50 kD and are 1.5 to 2 mm in diameter, with a smooth outer surface. The hollow fiber is housed inside immunoisolation chamber 43, which is a glass pipette or burette. Container 46 contains 0.5 milimole/L of CaCl 2 solution and it is aspirated through tubing 45 into immunoisolation chamber 43 but outside the hollow fiber. Aspiration into the tubing is controlled by manually squeezing plastic container 46. CaCl 2 is diffused through the hollow fiber due to its smaller molecular weight and will cause gelling of the Na alginate inside the hollow fibers, which will gel suspend cells inside the hollow fibers. Once the cells are gelled inside the hollow fibers, the fibers are removed and cut appropriately aseptically. The fibers are now ready for transplantation into a patient's body.
The apparatus can be operated outside an operating room with due precautions and a portable laminar hood, either in a specially designed section, or in a laboratory. Prior to and after each run, the apparatus chamber and all tubing should be sterilized. Fresh filters should be used each time, and proper leak proof connections should be insured before each run. Face coverings, gloves, and gowns should be worn by all operators, who should be trained in proper instrument handling, sterile aseptic handling, and the handling of all electrical connections.
All chemicals, such as Hank's solution, fetal calf serum, DTZ stain, Collagenase enzyme, DNASE, Mg, CaCl 2 , Na alginate with high `G` content and density gradient media should be freshly prepared in appropriate quantity. The proper chemicals could be prepared before hand in kit form to facilitate islet cell isolation procedures. In addition, the temperature of fluid entering chamber 1 is maintained at 37° C. and chamber 29 is cooled to 4° C.
Although the apparatus for islet cell transplantation and the method of using the same according to the present invention has been described in the foregoing specification with considerable details, it is to be understood that modifications may be made to the invention which do not exceed the scope of the appended claims and modified forms of the present invention done by others skilled in the art to which the invention pertains will be considered infringements of this invention when those modified forms fall within the claimed scope of this invention. | An apparatus for collecting a subpopulation of cells larger than a predetermined size from a collagenase distended organ by circulating fluid through a closed loop system. The closed loop system includes a digesting chamber to liberate cells from the organ, a cell collection chamber, and a filter adjacent the cell collection chamber for retaining cells larger than the predetermined size. The circulating fluid transports liberated cells through the cell collection chamber to the filter. Subsequently, the cells on the filter are flushed back into the cell collection chamber by a density medium. A tube then withdraws the desired subpopulation of cells from the cell collection chamber. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to a spark-ignition internal combustion engine, and more particularly to an apparatus for and a method of controlling a spark-ignition internal combustion engine of the type in which fuel is injected directly into a cylinder.
[0003] 2. Related Art
[0004] There is known a conventional system (Japanese Patent Unexamined Publication No. 2-153257) in which fuel is injected directly into a cylinder by use of the air pressure. A conventional diesel engine utilizes a stratified combustion, and therefore the maximum output or power is low although the fuel consumption under a partial load is enhanced. On the other hand, a conventional gasoline engine has a drawback that although the maximum output or power is high because of a premixture combustion, the fuel consumption under a partial load is worsened because of a pumping loss.
SUMMARY OF THE INVENTION
[0005] It is an object of this invention to provide an apparatus for and a method of controlling an internal combustion engine, in which under a partial load, a pumping loss is eliminated by a stratified combustion, thereby enhancing the fuel consumption, and during a maximum-output operation, the output or power is increased by a premixture combustion, and an engine torque is controlled to improve the operability (drivability), the fuel consumption and an exhaust cleaning effect.
[0006] In order to overcome the above problem of the prior art, under a partial load, an ignition source is provided in the vicinity of a fuel injection valve, and after the fuel is injected, the mixture is ignited, and a resulting flame is caused by a spray of the fuel to spread into a cylinder, thereby effecting a stratified combustion. On the other hand, when the load increases, so that soot and so on are produced in the stratified combustion, the fuel injection is effected a plurality of times in a divided manner, and a premixture is produced within the cylinder by the former-half injection, and a flame, produced by the latter-half injection, is injected into the cylinder to burn this premixture. Thus, the premixture is burned in a short period of time. When changing the gear ratio of a transmission, the amount of the fuel is changed so that a step will not develop in a torque.
[0007] When the amount of injection of the fuel is small as in a partial-load operation, the initiation of the injection and the ignition timing can be relatively close to each other, and therefore the fuel is not so much spread within the cylinder, and the combustion (stratified combustion) takes place in a relatively narrow range. In accordance with the increase of the load, the initiation of the injection is made earlier, so that the range of formation of the mixture (premixture) increases, and a premixture combustion takes place, thereby increasing the produced torque.
[0008] In accordance with the drive torque, the gear ratio of the transmission is selected, and if the drive torque need to be further increased, the gear ratio of the transmission is increased. When changing the gear ratio, the fuel injection amount is controlled so that the drive torque will not be varied. The fuel is injected into the combustion chamber of the engine by a fuel injection valve having a port (opening) therein, and therefore the fuel will not deposit on an intake manifold and other portions, and the speed of inflow of the fuel is high, and the engine torque can be controlled with a good response. The air/fuel ratio can be set to a large value, and therefore a throttle valve opening degree can be increased to reduce a pumping loss, thereby enhancing a fuel consumption. Moreover, since the air/fuel ratio can be increased, the amount of CO and HC in the exhaust gas can be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is a view of a control system according to a first embodiment of the present invention;
[0010] [0010]FIG. 2 is a vertical cross-sectional view of a combustion chamber;
[0011] [0011]FIG. 3 is a diagram showing the correlation between the air/fuel ratio A/F and HC in exhaust gas, as well as the relation between A/F and NOx in the exhaust gas;
[0012] [0012]FIG. 4 is a vertical cross-sectional view of a combustion chamber as in FIG. 2, but showing a second embodiment of the invention;
[0013] [0013]FIG. 5 is a chart showing a fuel injection timing;
[0014] [0014]FIG. 6 is a flow chart for the calculation of a fuel injection time;
[0015] [0015]FIG. 7 is a block diagram of a fuel pressure control device;
[0016] [0016]FIG. 8 is a view showing an EGR control system;
[0017] [0017]FIG. 9 is a diagram showing the construction of a control system according to a third embodiment of the invention;
[0018] [0018]FIG. 10 is a time chart showing the operation of an intake valve;
[0019] [0019]FIG. 11 is a perspective view showing rocker arms;
[0020] [0020]FIG. 12 is a map diagram for selecting a cam in connection with the relation between an engine speed and an accelerator opening degree;
[0021] [0021]FIG. 13 is a map diagram for selecting a cam in connection with the relation between the engine speed and an engine torque;
[0022] [0022]FIG. 14 is a diagram showing the correlation between the air/fuel ratio A/F and the engine torque;
[0023] [0023]FIG. 15 is a diagram showing the correlation between the fuel amount and the engine torque;
[0024] [0024]FIG. 16 is a block diagram of a control system according to a fourth embodiment of the invention;
[0025] [0025]FIG. 17 is a block diagram of a control system according to a fifth embodiment of the invention;
[0026] [0026]FIG. 18 is a map diagram showing the relation between the target air/fuel ratio and the engine torque;
[0027] [0027]FIG. 19 is a diagram showing the correlation of a throttle valve opening degree with the engine speed and the intake air amount;
[0028] [0028]FIG. 20 is a block diagram of a control system according to a sixth embodiment of the invention;
[0029] [0029]FIG. 21 is a block diagram of the control system, according to an embodiment of the invention, similar to the system of FIG. 20;
[0030] [0030]FIG. 22 is a top plan view showing the construction of a cylinder gasket of an engine in a seventh embodiment of the invention;
[0031] [0031]FIG. 23 is a vertical cross-sectional view of the construction of FIG. 22;
[0032] [0032]FIG. 24 is a view showing another embodiment of the invention;
[0033] [0033]FIG. 25 is a diagram showing the correlation between a required torque and an engine torque;
[0034] [0034]FIG. 26 is a diagram showing the correlation between a throttle valve opening degree and the required torque;
[0035] [0035]FIG. 27 is a diagram showing the correlation between the required drive torque and the gear position;
[0036] [0036]FIG. 28 is a diagram showing the correlation between a vehicle speed and the engine torque;
[0037] [0037]FIG. 29 is a flow chart for the control of a transmission and the engine;
[0038] [0038]FIG. 30 is a diagram showing the correlation between an accelerator opening degree and the required drive torque;
[0039] [0039]FIG. 31 is a diagram showing the correlation between the accelerator opening degree and the vehicle speed;
[0040] [0040]FIG. 32 is a diagram showing the correlation between the engine speed and the engine torque;
[0041] [0041]FIG. 33 is a diagram showing the correlation between the engine speed and the engine torque;
[0042] [0042]FIG. 34 is a time chart showing the change of the engine torque and the throttle valve opening degree with time;
[0043] [0043]FIG. 35 is a control block diagram of still another embodiment of the invention;
[0044] [0044]FIG. 36 is a time chart showing the change of the fuel amount and the vehicle acceleration with time; and
[0045] [0045]FIG. 37 is a time chart showing the change of the air amount, the fuel amount and the vehicle acceleration with time.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0046] [0046]FIG. 1 shows the construction of a control system according to a first embodiment of the invention. Fuel is fed from a fuel tank 1 to a fuel pump 2 , and the fuel is pressurized by this pump 2 . A pressure sensor 3 detects the pressure of the pressurized fuel, and feeds a pressure signal to a control circuit 5 . The control circuit 5 compares the fuel pressure with a predetermined target value, and if the fuel pressure is higher than this predetermined value, a spill valve 4 of the fuel pump 2 is opened to control the fuel pressure to the target pressure. The pressurized fuel is fed to a fuel injection valve 13 . A signal (torque signal) intended by the driver is fed from an accelerator pedal 19 to the control circuit 5 . In response to this signal, the control circuit 5 calculates an amount of one injection, taking a signal from an engine speed sensor 10 into account, and feeds a signal to an injection valve drive portion 20 of the fuel injection valve 13 . As a result, the fuel injection valve 13 is opened to inject the fuel into a combustion chamber 7 . The timing of injection of the fuel and the amount of injection (injection time) at this time are optimally determined by the control circuit 5 . A signal is fed from the control circuit 5 to an ignition circuit 22 at an optimum timing, and a high voltage is produced by the ignition circuit 22 , and is fed to an ignition plug 14 , so that the ignition plug 14 produces a spark to ignite the fuel injected into the combustion chamber 7 . The pressure within the combustion chamber 7 increases, and acts on a piston 9 to impart a rotational force to a crankshaft 16 , and tires 18 a and 18 b are driven through a transmission 15 and a differential gear 17 , thus causing a vehicle to travel. With respect to the torque produced by an engine 6 , the combustion pressure within the combustion chamber 7 is detected by a pressure sensor 8 , and is fed to the control circuit 5 , and is compared with the signal of the accelerator pedal 19 intended by the driver. The-result of this comparison is reflected on the next or subsequent fuel injection in the cylinder. An amount of the air in the engine 6 is measured by an air amount sensor, and the flow rate of the air is controlled by a throttle valve. The air is also controlled by a swirl control valve 28 , provided in an intake manifold 27 , so that a suitable turbulence can be formed in the cylinder. A valve lift of an intake valve 12 is controlled by a valve lift control device 11 . Combustion gas is discharged from an exhaust valve 21 .
[0047] The first embodiment of the present invention will now be described with reference to FIG. 2 which is a vertical cross-sectional view of the combustion chamber. The fuel injection valve 13 and the ignition plug 14 are provided at an auxiliary combustion chamber 23 formed at an engine head 25 . With respect to the positional relation between the fuel injection valve 13 and the ignition plug 14 , it is preferred that the ignition plug 14 be disposed downstream of the spray emitted from the fuel injection valve 13 . With this arrangement, a flame core produced by the ignition plug 14 is liable to be spread by the spray to the combustion chamber 7 and a cavity 24 formed in the piston 9 . However, if the ignition plug 14 is disposed too close to the spray, the ignition plug 14 gets wet with the spray, so that an incomplete ignition may be caused. Therefore, it is important to properly determine the above positional relation. By throttling an outlet portion 26 of the auxiliary combustion chamber 23 , the speed of injection or jetting-out of the flame core can be adjusted. In this case, if the throttling is excessive, a pressure loss develops, so that the heat efficiency is lowered.
[0048] [0048]FIG. 3 shows the relation between the air/fuel ratio A/F and the exhaust gas (HC, NOx). When the fuel injection timing is a crank angle of 90°, the peak value of NOx is obtained when A/F is nearly 16 . Such a change in the amount of discharge of NOx tends to be seen in a uniform mixture. The reason is that when the fuel injection timing is a crank angle 90° or up to an intermediate stage of the intake stroke, the injection spray spreads out over the entire area in the cylinder because of flows of the air within the cylinder which flows are caused by the movement of the piston and the intake operation. As the injection timing defined by the crank angle becomes greater, the air/fuel ratio, at which the peak value of NOx is obtained, becomes larger. At the same time, the production of NOx becomes gentle. Also, the amount of discharge of HC varies. Comparing the injection timing 90° with the injection timing 180°, the amount of HC at the injection timing 90° at A/F of nearly 15 is 3,800 ppmC while the amount of HC at the injection timing 180° at A/F of nearly 15 is 6,500 ppmc. The reason why the amount of HC thus differs at the same air/fuel ratio is that the air/fuel ratio at the region where the combustion is effected is different. Namely, the air/fuel ratio at the region where the combustion is actually effected at the injection timing 180° is smaller. Therefore, when the air/fuel ratio increases, a combustion failure (extinction or flame-out) occurs at the injection timing 90° at the smaller air/fuel ratio. The reason why the air/fuel ratio, enabling a stable combustion (the amount of HC does not increase), increases with the increase of the injection timing is that the increased fuel injection timing approaches the ignition timing, so that the fuel becomes less liable to spread, thus providing the stratified mixture. By thus selecting the injection timing, the uniform mixture and the stratified mixture can be formed freely. Therefore, when the engine torque is small, the injection timing is increased to be brought near to the ignition timing. As the torque increases, the injection timing is decreased to bring the mixture close to a uniform one.
[0049] [0049]FIG. 4 shows a vertical cross-sectional view of a combustion chamber of a second embodiment. In this embodiment, a fuel injection valve 13 is projected into the combustion chamber 7 , and an injection port is so formed that the fuel can spread widely within a cylinder. In this case, when the fuel is injected when a piston is lowered to a point near to a bottom dead center, the fuel impinges directly on a wall surface of the cylinder to form a wall flow. In this condition, a good combustion can not be expected. Therefore, where the injection valve injects a wide spray, the fuel need to be injected at such a timing that a cavity 24 is disposed near to an upper dead center, and that the fuel can be blown into the cavity 24 . For example, the injection of the fuel can be effected a plurality of times in a divided manner, as shown in FIG. 5. An early injection is effected at a crank angle of nearly 0° to form a uniform mixture. A combustion initiator is produced by a late injection effected at a timing near the ignition timing, and the uniform mixture produced by the early injection is rapidly burned thereby. The injection amount can be adjusted by any of the late injection and the early injection, and therefore the injection can be effected in the optimum condition. In the case where the injection is thus divided into the two injections (that is, the early injection and the late injection), the effect can be obtained also with the injection valve (FIG. 2) having a small injection angle.
[0050] [0050]FIG. 6 shows a flow chart for calculation of the fuel injection time in the case where the early injection and the late injection are effected. In Step 101 , an accelerator opening degree α and an engine speed Ne are read. At this time, if the air amount is measured, the air amount Qa may be also read. In Step 102 , the fuel amount Qf is calculated. In Step 103 , Qf>Qf 1 is judged. If the judgment result is “NO”, the program proceeds to Step 109 in which the injection time Tp 2 is calculated by adding an invalid injection amount Qx to Qf. In Step 110 , the fuel for Tp 2 is injected at the timing of the late injection, and the program is finished. If the judgment result in Step 103 is “YES”, the program proceeds to Step 104 in which Of 2 is calculated by subtracting a minimum injection amount Qf 0 from Qf. In Step 105 , the injection time Tp 1 is calculated by adding the invalid injection amount Qx to Qf 2 . The fuel for Tp 1 is injected at the timing of the early injection. In Step 107 , Tp 2 is calculated by adding Qx to Qf 0 , and the fuel for Tp 2 is injected at the timing of the late injection. Thus, for each of the early and late injections, it is necessary to add the invalid injection amount Qx.
[0051] [0051]FIG. 7 shows a control system for controlling the fuel pressure. Fuel for the fuel pump 2 is fed from the fuel tank 1 . The fuel pump 2 is driven by a motor 30 , and the pressurized fuel is fed to a high-pressure pipe 34 . Injection valves 13 a to 13 d , an accumulator 33 , the fuel pressure sensor 3 , and a relief valve 32 are mounted on the high-pressure pipe 34 . Gas is sealed as a damper in the relief valve 33 , and when the fuel pressure increases, the fuel flows into the accumulator 33 . When the pressure decreases, the accumulator 33 discharges the fuel into the high-pressure pipe 34 . When the fuel pressure becomes unduly high, the relief valve 32 allows the fuel to flow therethrough, thereby preventing the pressure increase. The fuel pressure sensor 3 feeds a signal, proportional to the pressure, to the control circuit 5 , and in response to this signal, the control circuit 5 feeds a signal to the electromagnetic spill device 4 to control the discharge amount of the fuel pump 2 , thereby controlling the fuel pressure. Also, in response to the signal from the pressure sensor 3 , the control circuit 5 feeds a signal to a controller 31 of the motor 30 to control the rotational speed of the fuel pump 30 , thereby controlling the fuel pressure. In this embodiment, although the electromagnetic spill device 4 and the controller 31 are both provided, the fuel pressure can be controlled by one of them. However, in the case where the fuel pump 2 is driven by the engine, only the electromagnetic spill device 4 is used for this purpose since the motor 30 is not provided.
[0052] [0052]FIG. 8 shows a control system diagram of EGR. The air enters the engine 6 through an air flow meter 35 , a throttle valve 37 and the intake manifold 27 , and is discharged as exhaust gas to exhaust pipe 41 . A catalyzer 39 is provided in the exhaust pipe 41 . Here, when EGR becomes necessary, the control device 5 feeds a signal to an EGR valve 38 to open the same. The control device 5 also feeds a signal to a throttle valve actuator 36 to close the throttle valve 37 to thereby reduce the pressure of the intake manifold 27 to a level lower than the atmospheric pressure. As a result, the exhaust gas flows from the exhaust pipe 41 to the intake manifold 27 through the EGR valve 38 in proportion to the negative pressure of the intake manifold. The rate of flow of the exhaust gas at this time is proportional to the negative pressure of the intake manifold, and therefore the pressure of the intake manifold is detected by an intake manifold pressure sensor 40 , and a signal is fed from this sensor 40 to the control device 5 , and the degree of opening of the throttle valve 37 is adjusted by the throttle valve actuator 36 . By controlling the degree of opening of the throttle valve 37 , the pressure of the intake manifold 27 can be controlled, and the EGR amount can be accurately controlled by a feedback control.
[0053] [0053]FIG. 9 shows a third embodiment of the present invention. The air is controlled by a throttle valve 213 , and is drawn into an engine through an intake manifold 214 . A lift of an intake valve 208 can be changed by switching cams 203 of different shapes. The switching of the cams 203 is effected by switching rocker arms 210 by a hydraulic control valve 202 . The hydraulic control valve 202 is operated, for example, by a solenoid. The degree of opening of the throttle valve 213 is controlled by a motor 212 . A sensor 220 for detecting a pressure within a cylinder is mounted on the engine. An injection valve 204 for injecting the fuel directly into the cylinder is mounted on the engine. A sensor 205 for detecting the air/fuel ratio of exhaust gas is mounted on an exhaust pipe. A catalyzer is also provided in the exhaust pipe. Preferably, the catalyzer or catalyst is of a type which can remove NOx even when an excessive amount of oxygen is present. Also, function of a three-way catalyst, which can remove HC, CO and NOx at the same time under the condition of a stoichiometric air/fuel ratio, is needed. Part of the exhaust gas is controlled by valves 215 and 218 which control the flow rate in the exhaust pipe. With this arrangement, the combustion temperature is decreased, thereby reducing the amount of NOx. These control valves are controlled by a control device 201 . In order to reduce the fuel consumption, it is preferred that the pressure within the intake manifold be reduced to a level close to the atmospheric pressure, thereby reducing a pumping loss. For this purpose, the throttle valve 213 is fully opened as much as possible. However, in the case where the exhaust gas is recirculated through a pipe 216 , it is necessary that the pressure within the intake manifold should be lower than the pressure within the exhaust pipe, and therefore the throttle valve is closed.
[0054] [0054]FIG. 10 shows the operation of the third embodiment of the present invention. According to the operating conditions, the lift of the intake valve cam is changed, as shown in FIG. 10. When a large amount of the air is required, the lift of the intake valve is set as at A. When the amount of the air is small, the lift of the intake valve is changed into a lift B or a lift C. By changing the lift, the overlap with an exhaust valve is also changed. During a high-output or power operation, the period of overlap between the exhaust valve and the intake valve is made longer. With this arrangement, the amount of the air can be changed by the lift of the intake valve.
[0055] [0055]FIG. 11 shows one example of the construction of rocker arms 221 , 223 and 224 and cams 225 , 226 and 227 . The rocker arm 223 and the cam 225 drive the intake valve for reciprocal movement. The rocker arm 226 and the cam 224 are not fixed to each other, and are in a free condition. When switching the cams, the rocker arm 224 and the cam 226 drive the intake valve for reciprocal movement. The rocker arm 223 and the cam 225 are not fixed to each other, and are in a free condition. With this construction, the cams can be switched. In this example, although the lift of the cam is changed, the shape of the cam may be changed so as to control the valve opening timing and the valve closing timing at the same time.
[0056] [0056]FIG. 12 shows a map for selecting the cam in connection with the degree of opening of an accelerator and the engine speed. In this example, the cam switching can be effected in a three-stage manner. When the engine speed is low, with the accelerator opening degree kept low, a cam A for a small lift is selected. As the engine speed and the accelerator opening degree increase, the cam is sequentially switched to those providing a larger lift.
[0057] [0057]FIG. 13 shows a map for selecting the cam in connection with the engine torque and the engine speed. In this example, the cam switching can be effected in a three-stage manner. The engine torque has target torque values predetermined with respect to the accelerator opening degree. When the engine speed is low, with the engine torque kept small, a cam A for a small lift is selected. As the engine speed and the engine torque increase, the cam is sequentially switched to those providing a larger lift.
[0058] [0058]FIG. 14 shows a method of controlling the amount of the intake air when switching the air/fuel ratio A/F. When the full-opening of the throttle valve or the cam for a large lift is selected, the fuel amount increases with the decrease of the air/fuel ratio, so that the engine torque (output torque) increases. At the air/fuel ratio of around 16, the amount of discharge of NOx tends to increase, and therefore the air/fuel ratio is skipped from 18 to 15. At this time, if the air/fuel ratio is switched to 15, with the air amount kept intact, the amount of the fuel increases, so that the engine torque increases as at C. This gives a sense of difference or a feeling of physical disorder. Therefore, when switching the air/fuel ratio, the air amount is reduced to prevent the increase of the fuel amount, and the engine torque is changed from A to B (FIG. 14), thereby reducing a shock. The air amount is adjusted by the throttle valve or by switching the cam. If this is effected by the throttle valve, the pressure within the intake manifold is decreased, thereby increasing the pumping loss. Therefore, preferably, this is done by switching the cam as much as possible. Also, when the engine torque decreases to such a level that the target engine torque is not achieved even if the air/fuel ratio is not less than 70, the air amount is adjusted by the cam or the throttle valve.
[0059] [0059]FIG. 15 shows the relation between the amount of the fuel and the engine torque (output torque). The engine torque can be increased by increasing the fuel amount, and therefore the engine torque can be controlled by the fuel amount.
[0060] [0060]FIG. 16 shows a fourth embodiment of the present invention. The amount Qf of injection of fuel is determined by an engine condition detection portion 301 (which detects the conditions of an engine such as an accelerator opening degree α and an engine speed N) and a fuel injection amount calculation portion 302 which calculates the amount Qf of injection of the fuel. In accordance with a charging efficiency map 303 , the amount of the air of the engine is calculated at a portion 304 , and the air amount by each cam is determined, thus calculating the air/fuel ratio. It is judged at a portion 305 whether or not the air/fuel ratio is within a combustible range. The cam is selected at a portion 306 , and the degree of opening of a throttle valve is determined at a portion 307 . If the air amount is excessive, the mixture becomes too lean, and therefore the cam is switched to one providing a smaller lift. In the injection within the cylinder, since the mixture within the cylinder is directly controlled, the limit of the lean mixture can be expanded as compared with a conventional intake port injection system, and therefore the range of the engine torque which can be controlled by the fuel amount is wider. Therefore, the engine torque can be controlled by the fuel amount without the need for finely controlling the air amount as in the conventional system.
[0061] [0061]FIG. 17 shows a fifth embodiment of the present invention. An accelerator opening degree is detected by a detection means 311 , and a target torque is determined by a calculation means 312 . An amount of fuel is determined by a fuel amount calculation means 313 in accordance with the target torque. If the air/fuel ratio is predetermined with respect to the engine torque (output torque) T at a portion 314 , the air amount Qa can be derived. The air/fuel ratio is judged by a judgment means 316 . If the air/fuel ratio is not less than 18, a throttle valve is fully opened, i.e. its opening degree θth-θmax, at a portion 318 , and the torque of the engine is detected by a torque detection means 319 , and the fuel injection amount is controlled so that the target torque can be obtained. On the other hand, if the air/fuel ratio is less than 18 , the air amount is controlled by the throttle valve 321 so that the target air/fuel ratio can be achieved. The air amount is controlled, for example, by the throttle valve opening degree θth or the lift by a cam. Here, the air amount may be detected by an air amount sensor 322 to control the air amount to a target value thereof.
[0062] [0062]FIG. 18 shows a map of the target air/fuel ratio. The air/fuel ratio is decreased with the increase of the engine torque (output torque) T. However, at point B, the air/fuel ratio is switched to a point C in a manner to skip over the air/fuel ratio value 16 . For further increasing the torque, the air/fuel ratio is reduced toward a point D. If the air/fuel ratio is further reduced, the mixture becomes too rich. Therefore, preferably, at this region, the air amount is detected, and the air/fuel ratio is controlled.
[0063] [0063]FIG. 19 shows the relation of the throttle valve opening degree θth with the engine speed N and the intake air amount Qa. For controlling the air amount by the throttle valve, the throttle valve opening degree is found from a map for the intake air amount. For effecting a more precise or fine control, the air amount is detected, and a feedback is effected.
[0064] [0064]FIGS. 20 and 21 shows a sixth embodiment of the present invention. If the air/fuel ratio is not less than 18 , the mixture is so lean that the drivability and an exhaust cleaning effect may be lowered. Therefore, a combustion variation is detected, and a throttle valve opening degree or a cam lift are so set as to reduce the air amount.
[0065] [0065]FIG. 22 shows a seventh embodiment of the present invention. An electrode or terminal 234 is embedded in a cylinder gasket 231 of an engine, and a high voltage is applied thereto from an electrode or terminal 232 . Screw holes 233 are formed in the gasket.
[0066] [0066]FIG. 23 is a vertical cross-sectional view of the portion of FIG. 22. A high voltage is applied across electrodes 238 and 239 from an ignition coil, thereby producing a spark discharge. With this arrangement, the mixture is ignited at a point near a cylinder wall surface and at other points as well, so that the combustion speed increases. Moreover, since the combustion is started adjacent to the wall surface, a so-called quench region near the wall surface is reduced, so that an amount of unburned hydrocarbon is reduced, and also a knocking is less liable to occur. Insulating layers 235 and 237 are provided on upper and lower surfaces of the gasket, respectively. If the electrode 239 is an earth or ground electrode, the insulating layer 237 may be omitted.
[0067] An embodiment of the present invention will now be described with reference to FIG. 24. The amount of the intake air is measured by an air flow meter 501 mounted on an intake manifold. An engine speed is detected by a crank angle sensor 509 . In accordance with the amount of the intake air into a cylinder, as well as the engine speed, the amount of fuel is determined, and the fuel is injected into the cylinder by a fuel injection valve 502 . The air amount is controlled by a throttle valve 551 , connected to an accelerator wire, and a throttle valve 550 controlled by a motor. The air amount may be controlled only by the throttle valve 550 ; however, if the throttle valve 551 connected to the accelerator wire is provided, the air amount will not become excessive even in the event of an abnormal operation of the throttle valve 550 . A catalyzer 506 , which can oxidize CO and HC, and can reduce NOx in an oxidizing atmosphere, is provided at an exhaust pipe 512 . Therefore, even if oxygen is present in the exhaust gas as in a lean combustion, NOx can be reduced. The air/fuel ratio is detected by an air/fuel ratio sensor connected to the exhaust pipe, and it is examined whether or not a target air/fuel ratio is achieved. If the air/fuel ratio is more lean that the target value, the fuel amount is increased. HC is required for reducing NOx in an oxidizing atmosphere, and the temperature of the catalyzer is so controlled that a maximum cleaning efficiency of the catalyzer can be achieved. Therefore, the temperature of the catalyzer is detected by a temperature sensor 528 , and the fuel injection amount and the ignition timing are so controlled that the target catalyzer temperature and HC can be obtained. A charging operation of a charger 514 can be controlled from the outside by a control device 508 . The charging operation is effected during a deceleration, thereby recovering a deceleration energy. The amount of the intake air into the engine can be increased by a supercharger 511 . The operation of the catalyzer is also influenced by the oxygen concentration in the exhaust gas, and therefore an air introduction passageway 534 is provided at an inlet of the catalyzer, and the air amount is controlled by a control valve 534 . The air may be supplied by an air pump 535 . When the air amount is increased, the catalyzer is cooled by the air, and therefore the air may be used for controlling the temperature of the catalyzer.
[0068] [0068]FIG. 25 shows the relation between a required torque Tv and the engine torque Te. The description will be given with respect to an example in which a transmission (gearbox) has a five-stage (five-speed) gear ratio. In a fully-opened condition of the throttle valve, the fuel amount is changed. When the required torque Tv is small, a 5th speed (5th gear) with a small or low gear ratio is selected. When the required torque Tv becomes larger, the fuel amount is increased to increase the engine torque Te. At this time, in order to achieve a stable combustion, the fuel amount is within a lean combustion limit, and the air/fuel ratio is varied in the range of 30 to 20 so that the amount of NOx can be kept small. However, in view of the cleaning or removing property of the NOx catalyzer, the range of the air/fuel ratio may be changed. Also, if the stable combustion limit allows the air/fuel ratio to be further increased, the air/fuel ratio may be more than 30. A pumping loss is reduced when the operation is effected with a large air/fuel ratio, and the fuel consumption is enhanced. When the required torque Tv becomes further larger, the gear ratio is increased into a 4th speed. At this time, if the gear is changed with the air/fuel ratio kept at 20, the drive torque becomes excessive, so that a step develops in the torque, thereby adversely affecting the drivability. Therefore, the fuel amount is reduced to decrease the torque to be produced, thereby preventing a stepwise change in the drive torque. Similarly, as the required torque is increasing, the gear is sequentially changed. The drive torque can be obtained in the following:
(Drive torque)=(Engine torque)×(Gear ratio)
[0069] Namely, the larger the gear ratio becomes, the larger the drive torque becomes. If the air/fuel ratio range of between 20 and 30 is fixedly selected, the gear ratio is selected so that a torque step will not develop. Assuming that the air/fuel ratio is 20 at a 1st speed, when a larger torque than that is required, the air/fuel ratio is further decreased. The required torque Tv is determined, for example, by the degree of opening of an accelerator. When the accelerator opening degree is large, the required torque Tv is large.
[0070] [0070]FIG. 26 shows the relation between the degree θ of opening of the throttle valve and the required torque Tv. When the required torque Tv is small, the throttle valve opening degree θ is decreased to reduce the engine torque. When the required torque becomes larger, the throttle valve opening degree θ is fully increased, and the gear ratio is sequentially changed. At the 1 st speed, the air/fuel ratio is skipped in view of the amount of production of NOx, so that a torque step develops. Therefore, the throttle valve opening is controlled in a closing direction so as to minimize a torque step. The throttle valve opening degree is controlled by a motor or the like. Since the control of the throttle valve can be made only in the closing direction of the valve, the engine torque will not increase against the driver's will. It is preferred that the throttle valve be fully opened, but if the operation can be effected in the fully-opened condition because of the performance of the engine, the operation is effected, with the throttle valve opened as much as possible.
[0071] [0071]FIG. 27 shows the relation between the required torque Tv and the gear position V for the vehicle speed. The gear position V is changed in accordance with the vehicle speed. The gear position V is increased with the increase of the vehicle speed. When the gear position V is decreased, the drive torque can be increased. The description will be given with respect to an example in which the vehicle speed is increased from a low speed, with the throttle valve fully opened. When the vehicle speed increases from the 1st speed (1st gear) to the lower limit of the 2nd speed, the air/fuel ratio is changed from 30 to 20, thereby minimizing or avoiding a torque step. As the required torque decreases, the air/fuel ratio is changed from 20 to 30. When the vehicle speed further increases, the gear is changed to the 3rd speed, and at this time the air/fuel ratio is changed to 20, thereby avoiding a torque step. A similar operation is repeated until the 5th speed. When the required torque is to be changed at the 1st speed, the air/fuel ratio is brought into 30 in the fully-opened condition of the throttle valve. When the torque need to be further increased, the fuel amount is increased to change the air/fuel ratio to 20. When the torque is small, the throttle valve opening degree is reduced to decrease the air amount. When the air/fuel ratio is constant, the fuel amount decreases with the decrease of the air amount, so that the torque is reduced. When the required torque is small, but is larger than that of the lower limit vehicle speed of the 5th speed, the 5th speed is selected. When the vehicle speed is made lower than the lower limit vehicle speed of the 5th speed, the engine speed becomes too low. When at the 5th speed in the fully-opened condition, a larger torque is required than that obtained with the air/fuel ratio of 20, the 4th speed is selected if the vehicle speed is higher than the lower limit of the 4th speed. At this time, the air/fuel ratio is changed to 30, thereby avoiding a torque step. When at the 4th speed in the fully-opened condition, the torque is to be made smaller than that obtained with the air/fuel ratio of 30, the throttle valve is closed. Similarly, when the required torque is to be increased, the gear is changed to the 3rd speed. The torque is controlled by sequentially changing the gear to the 1st speed in a similar manner.
[0072] [0072]FIG. 28 shows the relation between the vehicle speed lower than the lower limit vehicle speed of the 1 st speed and the engine torque Te at an outlet of a torque converter. Below the lower limit vehicle speed, when the transmission (gearbox) is kept in an engaged condition, the engine speed becomes too low, and in an extreme case, the engine is stopped. In such a speed region, a so-called lock-up (by which the transmission and the engine are directly connected together) is released, and the transmission is connected to the engine through the torque converter. When the vehicle speed decreases, there develops a slip region where there is a difference in rotational speed between the inlet and outlet of the torque converter. In the slip region, the torque is increased, and the engine torque at the outlet of the torque converter is increased. The engine torque can be changed by the air/fuel ratio. When the engine torque is, for example, not higher than 800 rpm, the lock-up is released. However, if the torque converter involves a slip, the torque converter produces a loss of transmission of the energy, so that the fuel consumption is worsened.
[0073] [0073]FIG. 29 shows a flow chart of the control of the transmission and the engine. The engine speed is calculated from the accelerator opening degree and the vehicle speed where number of gear shift positions r=5. When the engine speed is, for example, not more than 800 rpm, the gear position is shifted down by one speed (one gear) so that the engine speed will not be below 800 rpm. In the flow chart, although the gear position is sequentially shifted down, the gear position may be determined in accordance with the minimum allowable engine speed and the vehicle speed. Tf the gear position is larger than the 1st speed (1st gear), the lock-up is effected. When the gear position is the 1st speed, the gear position can not be shifted down any further even if the engine speed is lower than the minimum allowable engine speed, and therefore the lock-up is released. After the gear position is determined, the required engine torque (required torque) for the drive torque required by the driver is calculated. The fuel amount is calculated from the required torque, and the air/fuel ratio when fully opening the throttle valve is calculated. If the air/fuel ratio is not less than 30, the combustion becomes unstable, and therefore the throttle valve opening degree is so determined by calculation that the air/fuel ratio becomes 30. The associated actuators (the fuel injection valve, the throttle valve and the transmission) are so controlled that the fuel amount, throttle valve opening degree and gear position thus determined can be obtained. On the other hand, if the air/fuel ratio is not more than 20, the gear position is determined as (r-1), and the engine speed is calculated again. At this time, the fuel amount is controlled not to produce a drive torque step. Also, when the gear position is the 1 st speed (1st gear), the gear position can not be shifted down any further, and therefore the air/fuel ratio is changed from 12 to 15. Since the air/fuel ratio is skipped at this time so as to reduce the amount of discharge of NOx, the throttle valve opening degree is so determined by calculation that a drive torque step will not develop, and the actuators are controlled.
[0074] [0074]FIG. 30 shows the relation between the accelerator opening degree and the required drive torque. As the accelerator opening degree decreases, the required drive torque is decreased. At the same accelerator opening degree, the required drive torque is decreased as the vehicle speed increases. That the required torque can have a negative value means an engine brake. At the same accelerator opening degree, the higher the vehicle speed is, the more effectively the engine brake acts.
[0075] The required drive torque is determined for the accelerator opening degree and the vehicle speed, as shown in FIG. 31. These values are stored as a map in a memory of a computer for control purposes. For example, the accelerator opening degree, as well as the vehicle speed, is divided into 16, and 256 values of the required drive torque are stored.
[0076] [0076]FIG. 32 shows the relation between the engine speed and the engine torque. At the same engine speed, the larger the throttle valve opening degree is, the larger the torque is. By controlling the throttle valve opening degree, the engine torque can be controlled. Also, since the engine torque varies depending on the air/fuel ratio, the torque is controlled by changing the throttle valve opening degree and the fuel amount.
[0077] As to other advantageous effects of the present invention, the amount of the intake air is larger when using supercharging than when not using the supercharging, and the engine torque increases as shown in FIG. 33. If an exhaust turbo charger is used as the supercharging means, regardless of the driver's will, the torque characteristics with the supercharging are represented by a curve (a) while the torque characteristics without the supercharging are represented by a curve (b). Therefore, the engine output or power is abruptly increased when effecting the acceleration, and this gives a sense of difference or a feeling of physical disorder.
[0078] [0078]FIG. 34 is a time chart showing the change of the engine torque and the throttle valve opening degree with time. When an accelerator pedal is pressed down, the amount of the air is increased, so that the fuel injection amount is increased. When the supercharging is effected, the air amount is abruptly increased, the torque is increased as shown by (b) of FIG. 34 regardless of the driver's will, and this gives the sense of difference. When the supercharging is not effected, the time-dependent change of the engine torque with respect to a time-dependent change of the throttle valve opening degree is represented by (a) in FIG. 34. Thus, a certain period of time is required because of the inertia force before the speed by the supercharging becomes high, and therefore the supercharging becomes effective halfway during the acceleration.
[0079] [0079]FIG. 35 shows a control block diagram according to another embodiment of the present invention. The acceleration of the vehicle body is detected by an acceleration sensor, and if a desired drive torque is not obtained, the gear ratio (transmission ratio) of the engine is changed.
[0080] [0080]FIG. 36 shows the change of the fuel amount and the vehicle body acceleration with time. In order to determine the target acceleration for the accelerator opening degree as shown in this Figure, the fuel amount is increased to increase the engine torque. In the injection within a cylinder, the fuel can be injected directly into the cylinder, and therefore the fuel will not deposit on an intake manifold and the like, and the torque can be controlled with a good response. The acceleration is detected, and the fuel amount is so controlled that the target acceleration can be achieved.
[0081] [0081]FIG. 37 shows the change of the intake air amount, the fuel amount and the vehicle body acceleration with time. In order to determine the target acceleration for the accelerator opening degree as shown in this Figure, the fuel amount and the intake air amount are increased to increase the engine torque. The intake air amount is controlled by the throttle valve opening degree, but a delay occurs due to a volume of an intake manifold, so that the torque can not be controlled in a good response. Therefore, a large change of the engine torque is controlled by the air amount, and the control for small variations is effected by the fuel amount. In such a control, the range of change of the air/fuel ratio can be narrowed, and also the engine torque can be controlled over a wide range.
[0082] In the present invention, since the throttle valve full-open region is much used, the engine brake is less liable to act effectively at the time of the deceleration. Therefore, at the time of the deceleration, the electric charger is operated, thereby effecting an electric charging control. By doing so, the engine brake is achieved at the time of the deceleration, and also the energy at the time of the deceleration can be recovered. With respect to the decelerated condition, for example, when an injection pulse Tp is not greater than a predetermined value Tpc, the throttle valve opening degree is not greater than a predetermined value, and the engine speed Ne is not less than a predetermined value, it is judged that the deceleration occurs, and the electric charging operation is effected. Also, when the accelerator opening degree is not lower than a predetermined value, the charging operation is effected regardless of whether or not the injection pulse is below the predetermined value. During the charging operation, the charging target voltage is increased to increase a charging load. Other load such as a fuel heater may be used as the charging load. When the throttle valve is used, the throttle valve is closed during the deceleration.
[0083] In the present invention, the combustion time is shortened, the knocking is prevented, the compression ratio of the engine is increased, the heat efficiency is enhanced, and the fuel consumption is enhanced. The production of unburned hydrocarbon can be prevented by the stratified intake. The response to the fuel is enhanced by the fuel injection within the cylinder. Without increasing the pumping loss, the engine output or power can be controlled in a good response, thereby enhancing the drivability. | Under a partial load, a pumping loss is reduced by a stratified combustion to enhance a fuel consumption, and during the maximum output operation, the output is increased by a premixture combustion, and the output of an engine is controlled, thereby enhancing the drivability. Under the partial load, an ignition source is provided in the vicinity of a fuel injection valve, and after the fuel is injected, the mixture is ignited, and a resulting flame is caused by a spray of the fuel to spread into a cylinder, thereby effecting a stratified combustion. When the load increases, so that soot and so on are produced in the stratified combustion, the fuel injection is effected a plurality of times in a divided manner, and a premixture is produced within the cylinder by the front-half injection, and a flame, produced by the latter-half injection, is injected into the cylinder to burn this premixture. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to energy efficient streetlights and more particularly to an improved housing and assembly for an energy efficient streetlight wherein all major components of the lighting system may be readily removed from the housing for “in the field replacement” and wherein the housing features improved heat dissipation and isolation, among other improvements.
BACKGROUND OF THE INFORMATION
[0002] In recent years, there have been substantial improvements in streetlight technology. Previously, high intensity discharge (“HID”) streetlights typically used mercury-vapor, high pressure sodium or metal-halide lamp technologies. Recently, newer technology electrodeless induction, LED or plasma lamps have become to be used in streetlight applications. These lamps have several advantages over older HID systems which use magnetic ballasts. In particular, the newer energy efficient technologies last 5-10 times longer, experience significantly less degradation in light output over their service lives, offer a higher quality of light and are more energy efficient.
[0003] Induction lamps do, however, have certain drawbacks, mainly higher initial cost and heat sensitive components which compromise system life and performance. However, the greatly increased service life of induction lamps over that of other HID lamps offsets the increased initial costs and the heat sensitive components used in an induction lighting system can be protected via improvements to the streetlamp housing. High temperatures affect both the electrical and lamp components typically located inside the streetlight, which in turn will reduce overall service life of the system. Reducing the operating temperature of induction lamps by dissipating heat from the lamp by way of an improved housing as well as isolating heat sensitive electrical components from the lamp can significantly extend the life of the system. Improved lamp life is an important aspect of streetlight design because streetlights are typically mounted at the top of tall light-poles, which makes servicing in the field difficult and costly.
[0004] Another important aspect of streetlight housing design is serviceability and installation. Serviceability is particularly important in streetlights because streetlights are typically located along busy roads and highways and, as mentioned, are also typically located at the top of tall light-poles. The service of streetlights poses unusual dangers to workers because the lamps are typically located at substantial heights and therefore require special equipment to reach, and are typically situated in locations exposed to the hazards of vehicular traffic. In addition, streetlights must often be serviced “live,” i.e. with the power on, because it is frequently not practical to shut off power along an entire road or freeway for the purpose of servicing one particular streetlight. Replacement of lamps and their associated electrical components, i.e. the ballast, with the power on exposes maintenance workers to yet another inherently dangerous condition. Also, not infrequently, workers servicing streetlamps face a hazard of the natural type, namely bees, wasps or other insects that have built a nest inside the streetlight housing. In view of the worker hazards involved, it is desirable that streetlights be easy and quick to service.
[0005] It is also desirable that streetlights be quickly and easily serviced due to the high costs of maintenance. The costs associated with servicing a streetlight include replacements parts costs for the lamps, electronics and glass, but more importantly include the costs of a service crew. The costs of a service crew are significant and include worker salaries, training and insurance, as well as the cost of trucks equipped with lifts capable of reaching the streetlights.
[0006] There is a need in the art for a streetlight that provides improved cooling for the newer technology induction lamps and provides improvements in the lamp housing that reduce the time required to service and install the light. Even a relatively small reduction in the time required to service an individual streetlight leads to improved worker safety and substantially decreased costs given that municipalities must service relatively large numbers of lights. Even small municipalities typically must maintain and service several hundred streetlights while large cities are faced with the task of servicing tens of thousands.
SUMMARY OF THE INVENTION
[0007] The present invention streetlight improves upon the prior art by providing improved cooling for the newer technology induction lamps and by providing improvements in the lamp housing that reduce the time required to service the light. In its most basic form, the new streetlight comprises a main housing which includes separate, sealed, compartments for the induction lamp and the ballast or lamp electronics. Another separate compartment is provided for the photocell, the terminal block and the mast clamps. The lamp compartment of the housing features a multiplicity of heat sinks for conducting heat out of the compartment and into the housing where the heat is dissipated in the atmosphere through a combination of convection cooling and radiation. By providing separate lamp and ballast compartments, the ballast is better protected from the heat loading by the lamp. The ballast is further protected from heat by being attached to a finned heat sink (which also serves as a compartment cover). The mast clamps of the new streetlight are able accommodate a wide range of mast diameters from about 1¼″ to about 2½,″ or essentially all diameters in common use in the United States. Each of the compartments is sealed from elements and infestation from insects. In addition, the present invention streetlight includes features that allow each compartment of the light to be opened without the use of tools and the principle electrical components of the light, i.e. the lamp, ballast, and photocell can all be easily removed and replaced with simple hand tools, i.e. nothing more than a screwdriver. The light-glass which may occasionally require replacement due to breakage may also be easily removed with simple hand tools, i.e. a screwdriver.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a side view of the present invention streetlight.
[0009] FIG. 2 is a top plan view of the streetlight FIG. 1 .
[0010] FIG. 3 is a bottom plan view the streetlight of FIG. 1 .
[0011] FIG. 4 is an end view of the streetlight of FIG. 1 looking towards the end of the streetlight that is affixed to a mast or light-pole.
[0012] FIG. 5 is an end view of the streetlight of FIG. 1 looking towards the free end of the streetlight.
[0013] FIG. 6 is an end perspective view of the streetlight of FIG. 1 looking towards the end of the streetlight that is affixed to a mast or light-pole and showing the streetlight with the ballast and mast compartment covers open.
[0014] FIG. 7 is a top plan view of the streetlight of FIG. 1 showing the streetlight with the ballast and mast compartment covers open.
[0015] FIG. 8 is a side perspective view, partially exploded, of the streetlight of FIG. 1 showing the streetlight with the lamp compartment cover or lid open.
[0016] FIG. 9 is a top view of the streetlight of FIG. 1 showing the streetlight with the lamp compartment cover or lid open and with the lamp and reflector removed to reveal internal details.
[0017] FIG. 10 is a side view of an induction lamp suitable for use with the present invention streetlight of FIG. 1 , showing he base supports for the induction lamp and their ribbed or finned cooling surfaces.
[0018] FIG. 11 is a top view of an induction lamp suitable for use with the present invention streetlight of FIG. 1 showing the clamp and ribbed cooling surfaces of the supports for the induction lamp.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The present invention will now be described more fully with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. The invention may, however, may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
[0020] With reference to FIGS. 1 through 11 , the present invention streetlight 10 includes a main housing 12 having an outer surface 13 . The main housing 12 includes a lamp compartment 40 (see FIGS. 8-9 ), a ballast compartment 42 (see FIG. 6 ), and mast compartment 44 (see FIG. 7 ). Located within the lamp compartment 40 of the main housing 12 are a lamp 26 and a reflector 24 (see FIG. 8 ). Located within the ballast compartment is a ballast (lamp electronics) 32 . Located within the mast compartment 44 is a photocell 18 and a terminal block 34 which interconnects the electrical wiring between the lamp 26 , ballast 32 and photocell 18 . (Best shown in FIG. 7 .) The lamp 26 , ballast 32 , and photocell 18 are connected in electrical circuit and the ballast 32 is connected to an external source of electrical power which is typically introduced to the streetlight 10 through a mast 38 and light-pole (not shown) to which the streetlight 10 is connected.
[0021] Referring now to FIGS. 2-5 , and 8 - 9 in particular, the lamp compartment 40 is closed out by a lid 16 which is hinged to the main housing at one end by hinges 28 . At the end of the lid 16 opposite the hinge, the lid 16 latches to the main housing 12 via a latch 30 . Formed in the lamp compartment 40 , about its periphery, is a channel 48 for the receipt of a seal 46 . The channel 48 and seal 46 run the full length of the periphery of the lamp compartment 40 . The lid 16 includes a sealing edge 50 . When the lid 16 is closed and latched via latch 30 to the main housing 12 , the sealing edge 50 contacts the seal 46 located in the lamp compartment 40 and thereby seals the lamp compartment 40 and the lamp 26 and reflector 24 contained therein from the elements, i.e. from the weather. The latch 30 allows the lid to be opened and closed without the use of tools in most instances and thereby reduces the time needed to service, i.e. change-out, the lamp.
[0022] With reference to FIG. 9 , in addition to the seal 46 for the lid 16 , the lamp compartment 40 of the main housing 12 also includes a plurality of reflector supports 52 . The reflector supports 52 support the reflector 24 and serve as heat sinks to conduct heat out of the lamp compartment 40 . In one embodiment, the reflector supports 52 are integrally cast with the main housing 12 . All of the reflector supports are in physical contact with the reflector 24 for the purpose of conducting heat from the reflector. Though all of the supports are in contact with the reflector, typically, only certain of the supports will include holes 60 which accept fasteners (such as screws) which attach the reflector to the supports and thus securely hold the reflector and lamp 26 within the lamp compartment 40 .
[0023] Referring now to FIG. 8 , the lid 16 which closes out the lamp compartment 40 of the main housing 12 includes a light-glass 22 . The light-glass 22 is secured to the lid 16 by a plurality of clamps 94 , which attach to the lid by means of screws. Sandwiched between the light-glass and a supporting lip 19 formed into the lid 16 is a seal 96 which prevents water or insect intrusion into the lamp compartment through the light-glass/lid interface. The light-glass 22 may be easily removed from the lid for cleaning or replacement as the clamps 94 holding the glass to the lid require nothing more than a screwdriver or removal. The hinges 28 (best shown in FIG. 4 ) are sufficiently durable so as to prevent the light-glass from “flopping around” when the lid is opened.
[0024] With reference to FIGS. 8-11 , each lamp includes one or more lamp standoffs 54 which function to stand the lamp 26 off from the reflector 24 and to secure the lamp 26 within the lamp compartment 40 . The standoffs 54 comprise a clamp assembly 56 , which in one embodiment comprises a split-ring clamp, and a base portion 58 for interfacing with the reflector 24 and reflector supports 52 . The lamp standoffs also include a plurality of cooling fins or ribs 57 spaced radially about the perimeter of the standoffs. (See FIG. 10 .) The lamp standoffs 54 will typically be made of aluminum though other heat resistant materials such as zinc alloys and various grades of thermoplastics are suitable and known in the art. The base portion 58 of the lamp supports 54 include holes 60 which align with like holes 60 in the reflector 24 and reflector supports 52 so that the reflector and lamp, via the lamp supports, may be secured to the main housing, via the reflector supports, by one set of fasteners.
[0025] In operation, much of the heat generated by the lamp 26 is absorbed by the reflector 24 and conducted out of lamp compartment by the reflector supports/heat sinks 52 . Heat is conducted from the reflector supports to the outer surface 13 of the main housing 12 . Heat is transferred from the outer surface 13 of the main housing 12 to the atmosphere via convection cooling. The ambient air temperature surrounding the streetlight 10 will in virtually all cases be at a cooler temperature than the main housing after a few minutes of lamp operation. Thus, convection cooling occurs from the main housing to the atmosphere.
[0026] Referring now to FIGS. 6-7 , the main housing 12 also features a ballast compartment 42 . The ballast compartment 42 is separate from the lamp compartment 40 because the ballast electronics 32 are heat sensitive and it is desirable to isolate the ballast 32 from heat loading caused by the lamp 26 . The inventor has found that enclosing the ballast in a compartment separate from that of the lamp substantially reduces heat loading from the lamp. The ballast compartment is closed out by a closeout 62 . The closeout 62 includes cooling fins 66 . The ballast 32 is mounted directly to an interior surface of the closeout 62 . Heat generated by the ballast 32 is conducted through the closeout 62 and transmitted via convection, i.e. air flow past the cooling fins 66 to the atmosphere. Electrical connection between the ballast and the lamp is made via wiring which passes through a pass-through plug 70 . The pass-through plug 70 may be made from a heat resistant plastic or other material that is has good thermal and electrical insulation characteristics.
[0027] The ballast 32 includes a ground wire 102 . The ground wire 102 is secured to the inside of the ballast compartment to prevent removal, either accidentally or due to an act of vandalism, when the streetlight is in use.
[0028] Because the ballast 32 may occasionally fail during service and need to be replaced, the ballast closeout 62 is removably attachable to the main housing 12 via screws 64 equipped with large knobs. The knobs of the screws 64 are sufficiently large so as to allow the screws to be screwed and unscrewed without the use of tools in most instances. The ballast closeout 62 includes a weather seal 68 which encircles the periphery of the closeout 62 . When the closeout is fastened to the ballast compartment 42 by the screws 64 , the weather seal 68 contacts an outer edge or lip 74 of the ballast compartment 42 and thereby seals the compartment from the elements. The weather seal 68 may be made from numerous elastomeric materials as is known in the art.
[0029] With continued reference to FIGS. 6 and 7 , the main housing 12 also includes a mast compartment 44 . The mast compartment 44 is closed out by an upper cover 14 that is attached to the main housing 12 at one end by a hinge 20 . The mast compartment 44 and associated upper cover 14 have a hinged end 98 and a mast opening or mast receipt end 100 . (See FIG. 1 .) The upper cover 14 features a receptacle 17 for receipt of the photocell 18 . The mast compartment 44 features one or more mast-clamps 36 which accommodate the end of the mast 38 . Masts used to mount streetlights are generally round tubes of varying diameters. Masts with diameters of about 1¼″ to about 2½″ are in common use in various locales in the United States. The mast-clamps 36 of the present invention streetlight 10 feature adjustability sufficient to accommodate the aforementioned range of diameters. This range of adjustability eliminates the need for streetlight installation and service crews to carry several sizes of clamps to accommodate the various diameters of masts in common use.
[0030] Located within the mast compartment 44 is the terminal block 34 which interconnects the wiring for the ballast 32 , lamp 26 and photocell 18 . The present invention streetlight 10 by locating the majority of the wiring inside the mast compartment eliminates the need to use multiple rubber grommets to seal the wiring.
[0031] At the hinged end 98 (see FIG. 1 ) of the mast compartment 44 is a protruding surface 80 which protrudes from the main housing 12 and about which is affixed a strip seal 76 . At the mast receipt end 100 of the mast compartment is a mast seal 78 . The mast seal 78 is attached to a raised flange 82 protruding from the outer surface 13 of the main housing 12 . The mast seal includes a circular opening 84 through which the mast 38 slides when the streetlight 10 is assembled to the mast. When the upper cover 14 is closed, an inner surface 84 of the cover abuts the strip seal 76 at the hinged end 98 of the cover and seals the compartment 44 from water or insect intrusion at that end.
[0032] At the opposite or mast receipt end 100 of the cover 14 (see FIG. 1 ), the cover includes a flange 86 that has U-shaped opening 88 . When the cover is in a closed position, the U-shaped opening 88 fits about the mast and the mast seal 78 slides inside the cover and abuts an interior surface 90 of the flange 86 of the upper cover 14 . Like the ballast compartment closeout, the upper cover 14 is secured to the main housing 12 by screws 92 which are equipped with knobs that are sufficiently large to be easily removed without the use of tools in most instances. In this manner, the mast compartment is sealed from the elements and intrusion by insects and in particular by bees and wasps.
[0033] Materials and methods of manufacture to make the components of the present invention streetlight 10 are known in the art. Suitable materials for the main housing 12 include various aluminum and zinc alloys. The main housing will typically be made using a casting process. The main housing 12 may also be made from various thermoplastic materials in which instance the housing would be manufactured using a molding process. The light-glass 22 is typically made from heat resistant tempered glass. The seals used in the housing may be made from numerous elastomeric materials as is known the art. Suitable induction lamps 26 are also commercially available.
[0034] As may be seen from the above, an improved streetlight has been presented. The new streetlight features improved sealing from the elements, lower running temperatures and quicker servicing than has heretofore been available in streetlights.
[0035] The foregoing detailed description and appended drawings are intended as a description of the presently preferred embodiment of the invention and are not intended to represent the only forms in which the present invention may be constructed and/or utilized. Those skilled in the art will understand that modifications and alternative embodiments of the present invention which do not depart from the spirit and scope of the foregoing specification and drawings, and of the claims appended below are possible and practical. It is intended that the claims cover all such modifications and alternative embodiments. | An improved streetlamp featuring separate compartments for the lamp, ballast, photocell and wiring is provided. All electrical components of the streetlight are sealed from the elements and infestation from insects such as bees and wasps. All of the compartments may be readily opened without the use of tools and each electrical component and the light-glass can be readily removed and replaced with simple hand tools. Features for improved heat transfer to the atmosphere which results in a cooler running and longer lasting lamp are also provided. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for detecting pressure surges in a turbo-compressor.
Many methods are known for detecting a compressor surge. The most extensively used method involves monitoring the suction flow (intake volume) of the compressor. Whenever the suction flow falls below a prescribed minimum limit, it is assumed that normal throughflow has broken down and a surge is about to occur.
In this conventional method, the intake flow (volume) is measured by means of either an orifice or a nozzle positioned in the intake duct of the compressor. It is a drawback of this conventional method that the intake throttling device (the orifice or nozzle) causes a permanent pressure loss thereby increasing the total power consumption. Another drawback is that this method is not suitable for fully accurate operation. If an extremely fine or sensitive adjustment is made, the conventional method, under certain circumstances, may indicate surges although no surges have occurred; in the case of too coarse an adjustment, compressor surges might not be detected at all, under certain circumstances.
It has to be considered, when adjusting the system, that the flow at which surge begins varies with the load of the compressor. At low load, surge will start at low flow rates. If the load is increased, surge will start at higher flow rates.
Furthermore, another method is known which monitors the velocity at the compressor intake of the gas to be compressed. In this case, the gas velocity (which is proportional to the square of the flow rate) may be detected simply by comparing the static pressures in two positions of different flow cross-section, already present at the intake duct.
Advantageous with such a method is that the detecting orifice does not cause additional resistance to flow. However, a drawback is that the detecting system for measuring the gas velocity always provides a positive signal even if the flow direction has reversed under the action of a surge. In practice, a differential pressure transducer is employed for this purpose, the negative leg of which is connected to the smallest throttling cross-section of the compressor intake. The positive leg detects the pressure in the vicinity of the compressor intake flange; i.e., in a region of wide flow cross-section.
In this case, compressor surges are detected by monitoring the output signal of the differential pressure transducer for a pressure drop below a given minimum differential pressure. In carrying out this method, the differential pressure transducer may be replaced by a differential pressure switch which produces a signal whenever the differential pressure falls below a given presettable value.
However, this method likewise suffers from the drawback that, with too fine an adjustment, pressure surges are indicated even if no surges have occurred, whereas with too coarse an adjustment, surges cannot be detected at all.
Finally, it should be noted that both the flow rate signal and the velocity signal are superimposed on a "noise" signal due to whirls at the pressure tapping points. This leads to a fluctuating measured signal even at steady flow conditions.
SUMMARY OF THE INVENTION
It is the object of the invention to eliminate the above-mentioned drawbacks and to provide a method for detecting surges, as well as a circuit for carrying out this method, wherein every surge is indicated exactly, while avoiding indication errors.
It is a further object of the present invention to provide a surge detection circuit which lends itself to realization by relatively simple means and which can operate in an interference-free or trouble-free manner even when the noise level in the circuit, in the power supply or in the entire system, becomes high.
In this method, which is advantageously carried out by differentiating the signal X from the differential pressure transducer, the rate of change of the signal X is detected as a signal Y. The value of this signal Y will exceed a prescribed value with the occurrence of surge.
Additionally, this method according to the present invention may be improved by determining the magnitude of change of signal X, in addition to the rate of change of this signal. This change also exceeds a prescribed value when a surge occurs.
In order to be able to operate independently of the noise signals existing in every system, advantageously the rate of change of the signal X for forming the signal Y is determined by inputting the signal X to a summing circuit, both directly and after passing through a delay element.
Alternatively, it is possible that the delay element be designed to provide an output signal Y 1 in accordance with an exponential function. The method may also be carried out such that the rate of change of the signal X for forming the signal Y is determined by applying this signal to a summing circuit both directly, on the one hand, and with a delay through added time element, on the other.
As will be seen, the method according to the invention both positively and reliably indicates a compressor surge with a minimum of interference caused by noise signals. As the circuit is uncomplicated and uses only commercially available components, it can be manufactured inexpensively.
For a full understanding of the present invention, reference should now be made to the following detailed description of the preferred embodiments of the invention and to the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram of a system according to the present invention having a preferred embodiment of a surge protection circuit operating with a delay in accordance with an exponential function.
FIG. 2 is a block circuit diagram of another preferred embodiment of a circuit operating with a dead time delay element.
FIG. 3 is a block diagram of a system according to the present invention having a differentiator.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiments of the present invention will now be described with reference to FIGS. 1 and 2 of the drawing. Identical elements in the two figures are designated with the same reference numerals.
As shown in FIG. 1, the flow rate or flow velocity in either the intake or outlet of a compressor is detected and converted to a signal X in a signal converter 7. Such a conversion is well known in the art and need not be explained in detail here.
The measured value X is supplied to a summing point 1 both directly and with a delay produced by a delay element 2. This summing point 1 derives the difference between these delayed and undelayed values. Expediently, a first order delay element is used as the delay element 2, but other types of delay are also possible.
The term "first order delay element" should be understood to mean that, with a sudden change of the input signal, the output signal rises to this input value with a time delay in accordance with an exponential function. The time constant T 1 of this rise is variable. It constitutes an important settable parameter in this embodiment of the system.
The system according to the invention may also operate with delay elements of second order or higher order. It is operable even with the use of a mere "dead time" element 3 according to FIG. 2. The dead time element 3 produces an output identical to, but which lags the input signal by, the delay time T 2 .
The system according to the invention operates as follows: In the steady state condition, if noise is considered not to present, the measured value X does not change. Accordingly, the values Y 1 and X are identical since the output of the delay element has already reached its stationary terminal value. The value Y=X-Y 1 is therefore zero.
Now, when the measured value X increases, the value Y 1 follows with a delay in time. The difference Y=X-Y 1 becomes unequal to zero.
The faster X varies, the higher becomes the value Y. Small variations or changes of X result in small values of Y only. The same applies to slow variations. The slower the variation of X, the smaller will be the value of Y. Accordingly, the magnitude of output signal Y depends on the value and the rate of change of X.
The weighting of the rate of change is performed by the setting of the time constant T 1 of the delay element.
If T 1 is set too high, the system responds to every change of the input signal X regardless of how slow it is. The smaller T 1 is chosen, the lesser becomes the effect of slow changes.
Stated another way, given a time constant T 1 , the changes which take place very much slower than T 1 do not have any effect on the signal Y. Changes which occur much faster than T 1 , however, have an effect on the signal Y to the full magnitude of the input signal variation.
If a dead time or difference time element 3 is used instead of a first order delay element 2, the dead time T 2 constitutes the determining variable. In this case, the output signal Y has the value or magnitude by which the input signal X has varied in the period T 2 . The smaller T 2 is chosen, the smaller becomes the effect of slow changes of the input signal X on the output signal Y.
The signal Y is applied to a threshold or limit stage 4. The threshold stage 4 produces an output Z when a prescribed first threshold value is exceeded. By varying this threshold value, it is possible to control the amplitude weighting of the input signal change or variation. The higher the threshold value is set, the greater must be the input value change to cause the threshold stage 4 to respond.
The advantage of this system, as compared to the classical differentiation dX/dt, is that the amount or magnitude of the change of the signal X also has an effect, in addition to the rate of change. Small changes, as fast as they may take place, do not have any effect on the output of the threshold stage 4, as long as the amount or magnitude of the change is below the switching threshold of the threshold stage 4. Accordingly, this circuit, in a most simple manner, is rendered insensitive to measuring noise.
In contrast, the output signal of a classical differentiation circuit dX/dt is always proportional to the rate of change, irrespective of the magnitude of change.
In the alternative, the signal X can be passed through a classical differentiation circuit 5 as shown in FIG. 3. In this case, it would be desirable to provide a separate, additional threshold stage 6 which produces an output indicative of surge when the signal X exceeds a prescribed second threshold value.
When the threshold stage 4 or threshold stage 6 responds, thereby to detect the presence of a surge, the customary safety measures for protection of the compressor or the entire system may be taken. These measures may comprise, for example, immediate opening of a blow-off valve effecting other variations in the compressed gas system or in the operation of the compressor, as indicated in FIG. 1.
There has thus been shown and described a novel system for detecting surges in a turbo-compressor which fulfills all the objects and advantages sought therefor. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | A system (method and apparatus) are disclosed for detecting pressure surges in a turbo-compressor. Either the gas flow rate or gas velocity is measured at the intake or the outlet port of the compressor to produce a signal X. The rate of change of this signal X is determined and represented by a signal Y. The occurrence of surge is sensed and indicated by an output signal Z when the signal Y exceeds a prescribed threshold value. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to an exposure apparatus used in the semiconductor manufacture and the like and, more particularly, to an exposure apparatus for exposing a substrate to light while a region between a projection optical system and the substrate where the light passes is filled with liquid.
BACKGROUND OF THE INVENTION
[0002] FIG. 5 shows the schematic structure of a conventional exposure apparatus. Reference numeral 31 denotes a light source of the exposure apparatus used in the semiconductor manufacture and the like. For further miniaturization of exposure patterns, the light source 31 tends to use light having a shorter wavelength. The light source 31 has advanced from an i-line source to an excimer laser. The laser light source has further advanced from a KrF excimer laser to an ArF excimer laser. At present, in order to satisfy a demand for further micropatterning, it is proposed to use an F 2 laser or EUV light source.
[0003] Light emitted from the light source 31 is guided to an illumination optical system 33 through an introduction port 32 . The illumination optical system 33 removes an illumination variation and shapes the beam. Then, the resultant beam is applied, as illumination light, to a reticle 34 as an original of an exposure pattern. The reticle 34 is placed on a reticle stage 35 .
[0004] The light transmitted through the reticle 34 serves as pattern light to reduce and project a pattern onto a wafer 37 arranged in a plane optically conjugate to that of the reticle 34 through a projection optical system 36 .
[0005] The wafer 37 is placed on a wafer stage 38 driven by a linear motor, and undergoes step & repeat overlay exposure. Along with the necessity of a smaller integrated circuit line width, there has been developed the following semiconductor exposure apparatus. That is, the apparatus narrows down an exposure area as a slit to the central portion of the projection optical system 36 , at which optimal imaging is possible. Then, the apparatus also drives the reticle stage 35 by a linear motor to expose the wafer while synchronously scanning the wafer stage 38 and reticle stage 35 .
[0006] In recent years, a liquid immersion exposure apparatus has received a great deal of attention, which executes exposure while filling, with a liquid such as pure water, an exposure light transmission space (to be also referred to as a liquid immersion portion or liquid immersion region hereinafter) between the wafer 37 and the lowermost surface of the projection optical system 36 . By adopting such liquid immersion, a high NA can be attained owing to a high refractive index of a liquid. This amounts to grasping a chance to easily realize further micropatterning by adding a liquid immersion apparatus to an existing ArF exposure apparatus as a base without any F 2 laser or EUV light source which applies a large installation load (see, e.g., Japanese Patent Laid-Open No. 6-124873).
[0007] FIG. 6 is a view showing an example of the form of a liquid immersion exposure apparatus. FIG. 6 shows an arrangement in case of local liquid immersion. In liquid immersion exposure, a liquid immersion region is formed to be partitioned by a liquid immersion wall 21 on the lowermost surface of the projection optical system 36 . A liquid supply nozzle 22 and liquid recovery nozzle 23 are arranged to face the liquid immersion region. Liquid immersion exposure is based on the following method. That is, the liquid supply nozzle 22 supplies a predetermined amount of a liquid immersion fluid in synchronism with recovery by the liquid recovery nozzle 23 . With this operation, exposure is executed in the liquid-immersed state in which the liquid immersion region is filled with a liquid immersion fluid.
[0008] Since a liquid used for liquid immersion (to be also referred to as a liquid immersion fluid hereinafter) is regarded as even part of an optical device, it is demanded to strictly control purity, flow rate, and temperature. Ultra pure water is generally used as the liquid immersion fluid. Ultra pure water produced from factory equipments is thermoregulated by a cooler 24 , heater 25 , temperature sensor 26 , and thermoregulator 27 through a supply line 28 with a supply valve 30 , and supplied to a liquid immersion region through the liquid supply nozzle 22 .
[0009] When ultra pure water is to be used as the liquid immersion fluid, in order to avoid mixing of impurities such as particles or ions, the material of a liquid contact portion is limited to Teflon®-based and glass-based materials, and resins such as vinyl chloride, and metal-based materials cannot be used. This naturally applies to the materials of the cooler 24 , heater 25 , and temperature sensor 26 having liquid contact portions which contact the liquid immersion fluid.
[0010] Unfortunately, when a material such as Teflon is used for a device which thermoregulates the liquid immersion fluid, its heat transfer characteristic worsens. In particular, assume that ultra pure water is provided from factory equipments under the condition in which its flow rate and temperature are largely varied. In this case, the liquid immersion fluid is supplied to a liquid immersion region while disturbances are not completely eliminated due to a bad response characteristic of the thermoregulation system. Accordingly, there is a possibility that the imaging performance of liquid immersion exposure is decisively damaged.
[0011] Moreover, since a follow-up characteristic with respect to a heat capacity variation at the start of supply degrades, the operator must wait until the temperature stabilizes, resulting in a decrease in throughput.
SUMMARY OF THE INVENTION
[0012] The present invention has been made in consideration of the above background, and has as its object to provide an exposure apparatus which realizes high accuracy in thermoregulation of immersion liquid and high throughput.
[0013] In order to solve the above problem and achieve the object, according to an aspect of the present invention, there is provided an exposure apparatus for exposing a substrate to light via a reticle, the apparatus comprising: a projection optical system configured to project a pattern of the reticle onto the substrate; a nozzle configured to supply liquid to a region between the projection optical system and the substrate where the light passes; a circulation system configured to circulate liquid to be supplied to the nozzle; and a first thermoregulator configured to thermoregulate liquid in the circulation system.
[0014] In the above aspect, the circulation system includes a tank configured to store an externally supplied liquid.
[0015] In the above aspect, the circulation system further includes a first flow path configured to come from the tank and return to the tank.
[0016] In the above aspect, the first thermoregulator includes a heat exchanger configured to exchange heat with the liquid.
[0017] In the above aspect, the apparatus further comprises a detector configured to detect an amount of liquid in the tank, and a first flow regulator configured to regulate a flow rate of liquid externally supplied to the tank based on detection performed by the detector.
[0018] In the above aspect, the apparatus further comprises a valve configured to supply liquid from the circulation system to the nozzle.
[0019] In the above aspect, the circulation system includes a second flow regulator configured to regulate a flow rate of liquid refluxed to the tank.
[0020] In the above aspect, the apparatus further comprises a second flow path arranged between the valve and the nozzle, and a third flow regulator configured to regulate a flow rate of liquid in the second flow path.
[0021] In the above aspect, the apparatus further comprises a second flow path arranged between the valve and the nozzle, and a gas supply system configured to supply gas into the second flow path.
[0022] In the above aspect, the circulation system includes at least one of an ion exchanger configured to remove an ion dissolved in liquid, a degasifier configured to degasify liquid, and a sterilizer configured to sterilize liquid.
[0023] In the above aspect, a flow path of the circulation system has a portion configured to exchange heat with the projection optical system.
[0024] In the above aspect, the first thermoregulator includes a heater configured to heat liquid downstream of the heat exchanger.
[0025] In the above aspect, the apparatus further comprises a second thermoregulator configured to thermoregulate liquid externally supplied to the tank.
[0026] According to another aspect of the present invention, there is proposed a method of manufacturing a device, the method comprising steps of exposing a substrate to light via a reticle using an exposure apparatus as defined in any one of the above aspects; developing the exposed substrate; and processing the developed substrate to manufacture the device.
[0027] The present invention can provide an exposure apparatus which realizes high liquid immersion fluid thermoregulation accuracy and throughput.
[0028] Other objects and advantages besides those discussed above shall be apparent to those skilled in the art from the description of a preferred embodiment of the invention which follows. In the description, reference is made to accompanying drawings, which form apart thereof, and which illustrate an example of the invention. Such example, however, is not exhaustive of the various embodiments of the invention, and therefore reference is made to the claims which follow the description for determining the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the first preferred embodiment of the present invention;
[0030] FIG. 2 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the second preferred embodiment of the present invention;
[0031] FIG. 3 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the third preferred embodiment of the present invention;
[0032] FIG. 4 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the fourth preferred embodiment of the present invention;
[0033] FIG. 5 is a view showing a conventional exposure apparatus;
[0034] FIG. 6 is a view showing a liquid immersion fluid supply system of the conventional exposure apparatus;
[0035] FIG. 7 is a flowchart showing a device manufacturing method; and
[0036] FIG. 8 is a flowchart showing the wafer process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
[0038] Note that the embodiments to be described hereinafter are merely examples as implementation means of the present invention, and should be appropriately modified or changed in accordance with various conditions and the structure of an apparatus to which the present invention is applied. For example, the present invention is not limited to the embodiments to be described hereinafter and incorporates an arrangement obtained by combining the feature points of at least two of the second to fourth embodiments.
FIRST EMBODIMENT
[0039] FIG. 1 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the first preferred embodiment of the present invention. Constituent elements common to those in FIG. 5 are denoted by the same reference numerals.
[0040] The liquid immersion fluid supply system according to this embodiment is roughly divided into an immersion liquid thermoregulation and circulation system 8 and a thermoregulation fluid circulation system 10 used for a fluid other than a liquid immersion fluid.
[0041] A liquid immersion fluid provided from factory equipments (not shown) is firstly supplied from a supply line 28 of the immersion liquid thermoregulation and circulation system 8 . When an immersion liquid flow rate controller 1 controls the flow rate of the liquid immersion fluid, it is supplied to a heat-insulated tank 2 . The immersion liquid flow rate controller 1 has a shutoff valve 3 arranged between the heat-insulated tank 2 and supply line 28 and a liquid level sensor 4 arranged in the heat-insulated tank 2 . The immersion liquid flow rate controller 1 controls to open/close the shutoff valve 3 such that the liquid level in the heat-insulated tank 2 always falls within a predetermined range. The flow rate of the liquid immersion fluid supplied to the heat-insulated tank 2 is controlled equal to or more than that of a liquid immersion fluid supplied to a liquid immersion portion of the exposure apparatus.
[0042] The heat-insulated tank 2 is prepared to eliminate (absorb) disturbances such as a flow rate variation, pressure variation, and temperature variation of a liquid immersion fluid provided from the factory equipments. For a maximum flow rate and maximum temperature difference of a fluid to be supplied, the heat-insulated tank 2 must have a capacity enough to store a liquid immersion fluid for at least a heat capacity corresponding to an allowable temperature variation of the liquid immersion portion. In other words, allowable values of the flow rate and temperature of a liquid immersion fluid to be supplied to the heat-insulated tank 2 are determined on the basis of an allowable temperature variation of the liquid immersion portion and the tank capacity.
[0043] The heat-insulated tank 2 has a heat-insulated structure to suppress the influence of heat disturbances directly applied to the tank itself on a liquid immersion fluid. A thermoregulation system (not shown) is more preferably prepared to control the heat-insulated tank 2 to a predetermined temperature.
[0044] A pump 5 and heat exchanger 6 are arranged in a downstream line of the heat-insulated tank 2 in the immersion liquid thermoregulation and circulation system 8 . A recovery pipe 7 which branches from a line connected to the liquid immersion portion to reflux a liquid immersion fluid to the heat-insulated tank 2 is arranged in a downstream line of the heat exchanger 6 . As a characteristic feature of this embodiment, the recovery pipe 7 which branches to reflux the fluid to the heat-insulated tank 2 is arranged in the downstream line of the heat exchanger 6 in the immersion liquid thermoregulation and circulation system 8 . Note that the flow rate of a liquid immersion fluid from the pump 5 is controlled equal to or more than that of a fluid required to be supplied to the liquid immersion portion.
[0045] Moreover, a temperature sensor 9 is arranged upstream of the recovery pipe 7 in the downstream line of the heat exchanger 6 so as to control the temperature of a liquid immersion fluid to be detected by the temperature sensor 9 to a predetermined temperature.
[0046] A temperature control method of a liquid immersion fluid will be described next in addition to a description of the thermoregulation fluid circulation system 10 .
[0047] The thermoregulation fluid circulation system 10 has a cooler 11 , tank 12 , pump 13 , and heater 14 . A temperature-regulation fluid other than a liquid immersion fluid is supplied to the heat exchanger 6 in the immersion liquid thermoregulation and circulation system 8 to exchange heat with the liquid immersion fluid. At this time, the temperature sensor 9 outputs a detection signal to a thermoregulator 15 . The thermoregulator 15 then outputs a signal to the heater 14 , thereby controlling the temperature of the thermoregulation fluid such that the liquid immersion fluid of the temperature sensor 9 becomes a predetermined temperature.
[0048] When ultra pure water (e.g., having a resistivity of 17.8 MΩcm or more and inorganic ions of 0.01 ppb or less) is adopted as the liquid immersion fluid, a liquid contact portion of the heat exchanger 6 is preferably made of a material such as Teflon, glass, or vinyl chloride. To the contrary, a thermoregulator made of a metal having a good heat transfer characteristic is adopted for the thermoregulation fluid, thereby improving a response characteristic. The heat exchanger 6 naturally insulates the liquid immersion fluid and thermoregulation fluid except for heat. Hence, the liquid contact portion of the thermoregulation fluid can be made of a metal without posing any problem. However, since a slight amount of a fluid permeates, the thermoregulation fluid is preferably pure water to reduce the permeation phenomenon.
[0049] A nozzle supply controller 18 having a supply valve 16 and flow rate regulating valve 17 is arranged in a downstream line of the temperature sensor 9 in the immersion liquid thermoregulation and circulation system 8 . A nozzle supply pipe 29 extends from the supply valve 16 to the downstream side to communicate with a liquid supply nozzle 22 . A liquid immersion fluid is supplied to the liquid immersion region by opening the supply valve 16 of the nozzle supply controller 18 . At this time, the flow rate regulating valve 17 regulates the liquid immersion fluid to a predetermined flow rate. If the flow rate of a fluid refluxed from the recovery pipe 7 to the heat-insulated tank 2 is higher than that of a fluid supplied to the nozzle 22 , a flow rate variation at the start of supply can be reduced. This makes it possible to reduce a temperature variation caused by the heat exchanger 6 . Moreover, a recovery flow rate regulating valve 20 may be prepared for the recovery pipe 7 to control the flow rate of a fluid in the recovery pipe 7 such that the flow rate of a liquid immersion fluid which passes through the heat exchanger 6 does not vary during the opening and closing of the supply valve 16 .
[0050] When liquid immersion exposure is to be stopped, supply of a liquid immersion fluid to the liquid immersion region is stopped by closing the supply valve 16 in the nozzle supply controller 18 . However, a liquid immersion fluid remains in the nozzle supply pipe 29 . When the residual fluid is left, it corrodes and loses a desired purity, so the next start of liquid immersion exposure is interfered. To solve this problem, a valve 19 is arranged close to the downstream side of the supply valve 16 to recover the liquid immersion fluid in the nozzle supply pipe 29 at the stop of liquid immersion fluid supply and implant an inert gas into the pipe. This makes it possible to replace the residual fluid in the pipe between the supply valve 16 and the liquid supply nozzle 22 with an inert gas.
[0051] According to this embodiment, the immersion liquid thermoregulation and circulation system 8 can eliminate disturbances such as a temperature variation and flow rate variation of a liquid immersion fluid provided from the factory equipments, and a capacity variation at the start of supply. Moreover, even an ultra pure water thermoregulator configured to have a poor heat transfer characteristic implements high stability in temperature and flow rate, thus supplying a liquid immersion fluid to the liquid immersion portion at a high speed.
[0052] Also, at the stop of liquid immersion fluid supply, the influence of corrosion can be prevented because no liquid immersion fluid remains in the pipe.
SECOND EMBODIMENT
[0053] FIG. 2 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the second preferred embodiment of the present invention. Constituent elements common to those in the first embodiment in FIG. 1 are denoted by the same reference numerals.
[0054] As a characteristic feature of the second embodiment, an ultra pure water generation/maintenance function is newly prepared for the immersion liquid thermoregulation and circulation system 8 of the first embodiment.
[0055] More specifically, to add an ultra pure water generation function, an ion exchange membrane 41 to remove ions dissolved in a liquid immersion fluid is arranged in a downstream line (upstream of a recovery pipe 7 ) of a heat exchanger 6 . With this structure, even if the purity of pure water provided from factory equipments is somewhat low, ultra pure water with high purity can be provided. Moreover, when a degasifying or degassing membrane 42 to remove air bubbles in the liquid immersion fluid is arranged downstream of the ion exchange membrane 41 , the generation rate of microorganisms can be reduced and the generation of air bubbles can be suppressed. This contributes to prevention of degradation in image performance due to bubbles such as micro-bubbles in liquid immersion exposure. Moreover, when a UV lamp 43 is arranged in a heat-insulated tank 2 of an immersion liquid thermoregulation and circulation system 8 , it is possible to suppress the generation of microorganisms by sterilizing the microorganisms in the liquid immersion fluid using ultraviolet rays.
[0056] According to this embodiment, even if pure water provided from factory equipments is unsuitable for liquid immersion exposure, ultra pure water for liquid immersion exposure can be generated and maintained by preparing an ultra pure water generation function, degasifying or degassing function, and sterilization function. This makes it possible to provide a liquid immersion exposure apparatus which applies no large load to the factory equipments.
THIRD EMBODIMENT
[0057] FIG. 3 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the third preferred embodiment of the present invention. Constituent elements common to those in the first embodiment in FIG. 1 are denoted by the same reference numerals.
[0058] As a characteristic feature of the third embodiment, a precision thermoregulation means is newly prepared for the immersion liquid thermoregulation and circulation system 8 of the first embodiment.
[0059] More specifically, a heater 44 which can execute precise thermoregulation is arranged in a downstream line of a heat exchanger 6 , thus further improving the thermoregulation accuracy. A temperature sensor 45 arranged downstream of the heater 44 outputs a detection signal to a thermoregulator 46 . The thermoregulator 46 then outputs a signal to the heater 44 , thereby controlling the temperature of the liquid immersion fluid such that a liquid immersion fluid in the temperature sensor 45 becomes a predetermined temperature. Moreover, when a downstream line of the temperature sensor 45 is wound around an external cylinder or the like of a projection optical system 36 , a thermoregulated immersion liquid can be supplied to the projection optical system 36 to set the temperature of the liquid immersion fluid almost equal to that of the projection optical system 36 . This makes it possible to realize a thermoregulation system having excellent temperature stability. Also, the temperature sensor 45 is more preferably arranged near the projection optical system 36 .
[0060] According to this embodiment, the temperature stability is improved by precise thermoregulation and the temperatures of a liquid immersion fluid and projection optical system are made uniform. This makes it possible to provide an exposure apparatus which can prevent degradation in image performance by a temperature variation and supply a liquid immersion fluid having a constantly stable temperature.
FOURTH EMBODIMENT
[0061] FIG. 4 is a view showing a liquid immersion fluid supply system of an exposure apparatus according to the fourth preferred embodiment of the present invention. Constituent elements common to those in the first embodiment in FIG. 1 are denoted by the same reference numerals.
[0062] As a characteristic feature of the fourth embodiment, a thermoregulation means is newly prepared for the liquid immersion fluid supply line 28 of the first embodiment.
[0063] More specifically, since a heater 47 is arranged upstream of a heat-insulated tank 2 , it is possible to thermoregulate a liquid immersion fluid provided from factory equipments. A temperature sensor 49 arranged in a downstream line of the heater 47 outputs a detection signal to a thermoregulator 48 . The thermoregulator 48 then outputs a signal to the heater 47 , thereby controlling the temperature of the liquid immersion fluid such that a liquid immersion fluid in the temperature sensor 49 becomes a predetermined temperature.
[0064] According to this embodiment, a temperature disturbance applied to pure water provided from the factory equipments can be further decreased to reduce a temperature variation of an immersion liquid thermoregulation and circulation system 8 . This realizes an exposure apparatus which can prevent degradation in image performance by a temperature variation and supply a liquid immersion fluid having a constantly stable temperature.
[0065] Effects according to at least one of the first to fourth embodiments will be enumerated below. A thermoregulation and circulation system can eliminate disturbances such as a temperature variation and flow rate variation of a liquid immersion fluid provided from factory equipments, and a capacity variation at the start of supply. This makes it possible to provide an exposure apparatus which can eliminate the influence of a temperature variation of a liquid immersion fluid on an optical performance and has a stable image performance.
[0066] Even an ultra pure water thermoregulator configured to have a poor heat transfer characteristic implements high stability in temperature and flow rate, thus supplying a liquid immersion fluid to the liquid immersion portion at a high speed. Also, at the stop of liquid immersion fluid supply, the influence of corrosion can be prevented because no liquid immersion fluid remains in the pipe. This contributes to shortening of the startup time and improvement in throughput.
[0067] The present invention can provide an exposure apparatus which can execute liquid immersion exposure without applying any large load to factory equipments even if pure water provided from the factory equipments is unsuitable for liquid immersion exposure.
Device Manufacturing Method
[0068] A semiconductor device manufacturing process using the exposure apparatus will be described next. FIG. 7 is a flowchart showing the flow of the overall semiconductor device manufacturing process. In step S 1 (circuit design), a semiconductor device circuit is designed. In step S 2 (mask fabrication), a mask is fabricated on the basis of the designed circuit pattern.
[0069] In step S 3 (wafer manufacture), a wafer is manufactured using a material such as silicon. In step S 4 (wafer process) called a pre-process, the exposure apparatus is caused to form an actual circuit on the wafer by lithography using the mask and wafer. In step S 5 (assembly) called a post-process, a semiconductor chip is formed by using the wafer formed in step S 4 . This process includes an assembly process (dicing and bonding) and packaging process (chip encapsulation). In step S 6 (inspection), the semiconductor device manufactured in step S 5 undergoes inspections such as an operation confirmation test and durability test. After these steps, the semiconductor device is completed and shipped in step S 7 .
[0070] The wafer process in step S 4 includes the following steps ( FIG. 8 ): an oxidation step of oxidizing the wafer surface; a CVD step of forming an insulating film on the wafer surface; an electrode formation step of forming an electrode on the wafer by vapor deposition; an ion implantation step of implanting ions in the wafer; a resist processing step of applying a photosensitive agent to the wafer; an exposure step of causing the above-mentioned exposure apparatus to expose the wafer having undergone the resist processing step to form the circuit pattern; a development step of developing the wafer exposed in the exposure step; an etching step of etching the resist except the resist image developed in the development step; and a resist removal step of removing an unnecessary etched resist. These steps are repeated to form multiple circuit patterns on the wafer.
[0071] As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.
[0072] This application claims the benefit of Japanese Patent Application No. 2005-032357, filed Feb. 8, 2005, which is hereby incorporated by reference herein in its entirety. | An exposure apparatus for exposing a substrate to light via a reticle includes a projection optical system configured to project a pattern of the reticle onto the substrate, a nozzle configured to supply liquid to a region between the projection optical system and the substrate where the light passes, and a circulation system configured to circulate liquid to be supplied to the nozzle, and a first thermoregulator configured to thermoregulate liquid in the circulation system. | 6 |
RELATED APPLICATIONS
This application is a continuation of U.S. Ser. No. 11/511,772, filed Aug. 29, 2006, the entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to rule compliance checking, and more particularly, to a method and apparatus for checking whether business processes comply with predefined compliance rules, and a computer program product for implementing the checking method.
BACKGROUND OF THE INVENTION
Almost every enterprise, regardless of industry, needs to face various compliance rules that might affect decisions of the enterprise. For instance, any enterprise must comply with laws and regulations issued by their countries as well as guild regulations and practices of the industry to which it belongs while running business operations. In order to efficiently manage business operations, enterprises often prescribe some specific bylaws for their business themselves. In addition, if enterprises want to do international trades, they are required to comply with some international accords or regulations. Enterprises should guarantee their business operations to comply with these regulations, not only because their supervisions often check the situation of compliance with laws and regulations but also because compliance with these compliance rules can protect their lawful interests. Thus, compliance with laws/regulations is very important to business operations of enterprises.
Currently, whether business operations comply with rules is usually checked manually. In the course of checking, one or a group of professionals with a good command of various laws and regulations and enterprise business operations are required so as to make a comparison or judgment between business operations and predefined compliance rules one by one, using some manual method.
Such a conventional method, which relies on human experience and judgment, can check the situation of compliance with corresponding rules (laws and regulations) of only one business operational process every time, and hence, it is not advantageous to multiple checking on plural business operational processes. Besides, such manual checking can hardly or cannot effectively reuse information resources generated during the preceding checking. For instance, one identical rule might be parsed again and again in the course of compliance situation checking on different business operational processes. Moreover, the crux is that manual checking is subject to man-made factors. Due to differences of specific operating personnel in experience, perception and proficiency level, an obtained compliance checking report might have various results, which rebates the reliability and veracity of the report to a great extent.
In summary, the manual mechanism in the prior art for checking whether business operations comply with predefined compliance rules has a multitude of inherent defects, and consequently, it cannot meet much higher requirement of modern enterprises on veracity of regulation compliance checking report, high efficiency of checking process and other aspects.
SUMMARY OF THE INVENTION
To overcome defects in the prior art, the present invention provides a method and apparatus capable of checking automatically whether business operations comply with predefined rules, as well as a computer program product implementing the method.
According to an aspect of the present invention, provided is a method for rule compliance situation checking, including the steps of: a) establishing compliance rule models for predefined compliance rules and establishing business operational models for business processes; b) normalizing vocabularies in the compliance rule models and the business operational models; c) checking whether the compliance rule models are satisfied by the business operational models; and d) outputting a report on checking results.
According to another aspect of the present invention, provided is a system for rule compliance situation checking, comprising: a compliance rule model repository for storing compliance rule models established for predefined compliance rules; a business operational model repository for storing business operational models established for business processes; normalization means for normalizing vocabularies in the compliance rule models and the business operational models; a checking engine for checking whether the compliance rule models are satisfied by the business operational models; and reporting means for generating and outputting a checking result report.
Using the method and system for rule compliance situation checking according to the present invention, users can perform fast and effective automatic checking of rule compliance situation, which avoids interference of man-made factors in checking process to a great extent and thus guarantees accuracy of checking result. Furthermore, business operational and predefined compliance rules are reserved in corresponding storage repositories after computer modeling and processing, so that users can not only do different rule compliance checking on one identical business operational model but also check different business operational models repeatedly using the same compliance rule model. As a result, the advantage of repeated reusing of the same model saves significantly human resource and time. In addition, the computer aided rule compliance checking can easily take tactical adjustments and support users' varied needs conveniently and rapidly.
The present invention also provides storage medium with a machine-readable computer program, the computer program comprising instructions for enabling a processor to implement the method according to the present invention.
Other characteristics and advantages of the present invention will become more apparent from the detailed description of the embodiments of the present invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a summary flow chart of rule compliance situation checking according to an embodiment of the present invention.
FIG. 2 is a schematic flow chart of compliance rule model establishment according to an embodiment of the present invention.
FIG. 3 is a schematic view of a visualized compliance rule tree corresponding to a simplified compliance rule model.
FIG. 4 is a schematic view of a business operational model, its formalized model and its simplified model according to an embodiment of the present invention.
FIG. 5 is a processing flow chart of checking whether a compliance rule model is satisfied by a business operational model according to an embodiment of the present invention.
FIG. 6 is a visualized checking result report generated based on a compliance rule model according to an embodiment of the present invention.
FIG. 7 is a schematic structural block diagram of a system for rule compliance situation checking according to an embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the detailed embodiments of the present invention will be described in combination with the accompanying drawings.
FIG. 1 is a summary flow chart of rule compliance situation checking according to an embodiment of the present invention. The processing starts with step 100 . In step 101 , predefined compliance rules described in natural language, e.g. laws and regulations, are abstracted as computer-processible mathematical or logical models, and business operational models are built for enterprises, government departments and other organizations in the real world using business operational modeling tools.
In step 102 , vocabularies used in the models are normalized. That is, the compliance rule models and the business operational models built in step 101 are semantically normalized so as to conduct match checking with respect to the definitions and relations thereof.
In step 103 , it is checked whether the above compliance rule models are satisfied by the above business operational models, so as to determine whether the business operation complies with predefined compliance rules. In step 104 , a checking result report reflecting rule compliance situation of the business is automatically generated and output. Eventually, the processing flow ends with step 105 .
Hereinafter, each of the steps is described in detail in the order of steps in the flowchart as shown in FIG. 1 . First, explanation is given on how to build corresponding models for predefined compliance rules, e.g. laws and regulations, and for business operations respectively in FIG. 1 (step 101 ). It should be understood here that, although the processes of building the two models are explained in certain order, the models can be built in parallel or accordance with whatever needs.
For rules such as laws and regulations that are usually described in natural language, it is hard to directly process these natural languages during automatic computer processing. Therefore, there is a need to re-define such compliance rules described in natural language into a computer-processible form. For instance, a definition language may be utilized to extract various basic concepts as well as the logic relations among the concepts from a compliance rule and then abstract the compliance rule as a logical formula. In an embodiment of the present invention, the definition rule defines 11 kinds of concepts used for abstract rules, including: Action, Actor, Resource, Organization, Time, Cost, Trigger, Artifact, Location, Principle and Purpose; as well as all possible relations between these 11 concepts. Actually, selection of these concepts is not limited to an absolute standard, and users can define different concepts in their language and define different relations to denote the relationship among concepts, in accordance with variant needs.
FIG. 2 is a schematic flow chart of compliance rule model establishment according to an embodiment of the present invention. Here, a specific regulation is used to explain rule modeling in detail. For instance, the regulations of “Public issuance of securities must conform to the criteria prescribed by laws and administrative regulations, and be submitted to the securities supervision and administration institution under the State Council or the departments authorized by the State Council according to law for verification and approval or examination and approval; no unit or individual shall, without verification and approval or examination and approval according to law, publicly issue securities in society.” ( China Securities Law, Chapter II, Article 10), is modeled as an example.
First, the processing of rule modeling starts with step 200 . In step 201 , all the concepts included in the rule are found. For example, the following concepts are included in the above-mentioned regulations:
Action: “public issuance of securities”, “submit application for issuance of securities”; Trigger: “verification and approval or examination and approval”; Organization: “securities supervision and administration institution under the State Council”, “departments authorized by the State Council”; Principle: “criteria prescribed by laws and administrative regulations”, “law”; Purpose: “verification and approval or examination and approval”.
In step 202 , the relations among the concepts appearing in the rule are defined. Hereinafter, the relations among the aforesaid concepts are indicated in a form of function:
Concept 1 _Concept 2 _Relation (Concept 1 (content), Concept 2 (content))
This function denotes the interrelation among the specific contents of “Concept 1 ” and “Concept 2 ”. For example, the following relations are contained in the aforesaid regulations:
Action_Principle_with (Action (“public issuance of securities”), Principle (“criteria prescribed by laws and administrative regulations”)), indicating the criterion that “public issuance of securities” must comply with “criteria prescribed by laws and administrative regulations”; Action_Trigger_export (Action (“submit application for issuance of securities”), Trigger(“verification and approval or examination and approval”)), indicating the logic relation that “submit application for issuance of securities” exports “verification and approval or examination and approval”; Trigger_Organization from (Trigger (“verification and approval or examination and approval”), Organization (“securities supervision and administration institution under the State Council”)), indicating the regulation that “verification and approval or examination and approval” must be conducted by “securities supervision and administration institution under the State Council”; Trigger_Organization_from (Trigger (“verification and approval or examination and approval”), Organization (“departments authorized by the State Council”)), indicating the regulation that “verification and approval or examination and approval” must be conducted by “departments authorized by the State Council”; Action_Action_until (Action (“submit application for issuance of securities”), Action (“public issuance of securities”)), indicating the time sequence from “submit application for issuance of securities” till “public issuance of securities”; Action_Principle_with (Action (“submit application for issuance of securities”), Principle (“law”)), indicating the criterion that “submit application for issuance of securities” must conform to “law”; Action_Purpose for (Action (“submit application for issuance of securities”), Purpose (“verification and approval or examination and approval”)), indicating that the purpose of “submit application for issuance of securities” is to obtain “verification and approval or examination and approval”.
In step 203 , a formalized rule model corresponding to the rule (e.g. laws and regulations) is determined. For instance, the aforesaid regulations can be defined as:
IF Occurrence (Action (public issuance of securities))
THEN
Action_Principle_with (Action (“public issuance of securities”), Principle (“criteria
prescribed by laws and administrative regulations”))
AND
Action_Trigger_export (Action (“submit application for issuance of securities”), Trigger
(“verification and approval or examination and approval”))
AND
{
Trigger_Organization_from (Trigger (“verification and approval or examination and
approval”), Organization (“securities supervision and administration institution under the
State Council”))
OR
Trigger_Organization_from (Trigger (“verification and approval or examination and
approval”), Organization (“departments authorized by the State Council”))
}
AND
Action_Action_until (Action (“submit application for issuance of securities”), Action
(“public issuance of securities”))
AND
Action_Principle_with (Action (“submit application for issuance of securities”), Principle
(“law’))
AND
Action_Purpose_for (Action (“submit application for issuance of securities”),
Purpose (“verification and approval or examination and approval”));
In step 204, the defined compliance rule model is simplified. For instance, the compliance
rule model for the aforesaid regulations may be simplified as:
IF Occurrence (Action (“public issuance of securities”))
THEN
Action_Action_until (Action (“submit application for issuance of securities”)
With
(Principle (“criteria prescribed by laws and administrative regulations”)
AND Principle (“law”))
For
Purpose (“verification and approval or examination and approval”)
Export
Trigger (“verification and approval or examination and approval”)
From
(Organization (“securities supervisions and administration institution under the State
Council”)
OR Organization (“departments authorized by the State Council”,))
Action (“‘public issuance of securities’))Finally, the processing on compliance rule modeling
ends with step 205.
The process of compliance rule modeling is described above in detail. It should be noted that, the step of simplifying the defined compliance rule model in step 204 is not indispensable but optional. However, those skilled in the art understand that such simplification makes subsequent processing much simpler and more intuitive.
In order to make the compliance rule model more intuitive, preferably, the model may be visualized as a rule tree. FIG. 3 shows a visualized rule tree of the compliance rule model simplified in step 204 . As shown in FIG. 3 , root node 300 denotes the logic structure of “IF . . . THEN”; nodes 301 and 302 denote the relations among the concepts of the rule; nodes 303 , 304 , 305 , 307 , 308 , 309 , 310 , 312 and 313 denote the concepts in the aforesaid rule; nodes 306 and 311 are logical operators for connecting the concepts; and the notes on the arrows denote the relation predicates among the concepts.
Referring to the accompanying drawings, building of business operational models is described in detail below. FIG. 4 is a schematic view of a business operational model, its formalized model and its simplified model according to an embodiment of the present invention, wherein reference numeral 40 denotes a business operational model built for public issuance of securities, reference numeral 41 denotes a Petri-Nets formalized model of the aforesaid model, and reference numeral 42 denotes a simplified model of the formalized model 41 .
As shown in FIG. 4 , existing computer tools for business operation modeling may be used to build the business operational model 40 . Included in the business operational model 40 are: start node 400 , task nodes 401 , 402 , 403 , 404 , 405 and 406 , decision mode 407 as well as a plurality of end nodes 408 , which are logically connected via arrows. The start node denotes start of the business process. The end nodes denote every possible end of the business process. The task nodes denote a task needed to be carried out currently. The decision node means to make judgment on the basis of the current state and select one from the neighboring tasks denoted by the plurality of subsequent task nodes as the task to be performed next according to the result of judgment.
Each of the task nodes corresponds to an attribute list for describing the task. On the attribute list, there are recorded attribute values of the node, which corresponds to the predefined attributes. In the present embodiment, attributes such as “Action”, “Organization”, “Trigger”, “Principle” and “Purpose” are defined for each task node. For instance, the attribute “Action” defines the action performed by the task node and may be used as a name for identifying the task node; the attribute “Organization” defines the body performing the task; “Trigger” defines the premise of performing the task, the value of which may be the occurrence of “Action” of the preceding task node by default; the attribute “Principle” defines the principle to be observed while carrying out the task; the attribute “Purpose” defines the purpose of carrying out the task, etc. For a specific task node, its meaningless attributes or attributes which do not need to be specifically defined may be set as null. For instance, for the task node 401 , the attribute value of “Action” is “receive application for public issuance”, defining the task to be carried out currently; the attribute of “Organization” is “securities regulatory commission”, defining the body carrying out the task of “receive application for public issuance”; and the attributes “Principle” and “Purpose” do not have corresponding definition values set, but are set as null.
It is to be understood to those skilled in the art that the attributes of a task node may be increased or reduced in accordance with the domain of the current business operational model. In order to make a comparison between business operational model and compliance rule model in a more effective way, it is better to define types of the attributes of a task node as corresponding to types of the concepts of a compliance rule model.
Moreover, it is better to formalize the above business operational model 40 , transforming into a computer-processible formalized model. A plurality of methods can be utilized to formalize the business operational model, such as Petri Nets, Process Algebras, Z method, B method, Communicating Finite State Machine, and so on. FIG. 4 shows schematically only the Petri Nets-formalized model 41 and its simplified model 42 of the business operational model 40 .
It is to be understood that, although the business operational model is formalized and simplified, the formalized and simplified models still keep the logical relations of the original business operational model and each of the nodes is still restricted by the attributes of the corresponding task node. That is to say, the formalization and simplification does not change the substantive contents of the business operational model, but facilitates the business operational model to be processed more easily in subsequent steps.
Next, the step (step 102 ) of normalizing compliance rule model and business operational model in the flow chart shown in FIG. 1 is described. Due to difference in domain that a model belongs to, focal angle and subjective describing manner of a model builder in the course of modeling, the following situation is likely to arise: terms (vocabularies, describing manners etc.) contained in compliance rule model and business operational model and used for the same concept, relation or those concept and relation which can be currently deemed identical are different. For example, in the above-described compliance rule model, the concept “Organization” includes “securities supervision and administration institution under the State Council” and “departments authorized by the State Council”; while in the business operational model, the “Organization” attribute of the task node is expressed as “securities regulatory commission”. Although “securities supervision and administration institution under the State Council” or “departments authorized by the State Council” and <“securities regulatory commission” have the same meaning and function in the context, but they are different in expression. In this case, it is very difficult to conduct rule compliance situation checking on compliance rule model and business operational model. Therefore, it is necessary to normalize compliance rule model and business operational model prior to checking, so as to achieve term consistence. That is, “securities supervision and administration institution under the State Council” or “departments authorized by the State Council” and “securities regulatory commission” are assumed to be the same concept. In addition, even if the terms used in the two models are made consistent at the beginning of modeling (which is usually quite difficult, labor intensive and costly because of large amount of vocabularies), there is still a need to assume the consistence of these terms before checking. Therefore, such a normalization step of assuming the consistence of terms between two models is highly necessary and critical to the whole method for rule compliance situation checking.
A feasible mechanism of model semantic normalization is to build a standard vocabulary repository and then enforce semantic consistence or confirm semantic consistence between the two models by using the standard vocabulary repository. In this solution, an arrangement manner similar to synonymous vocabulary repository may be adopted to classify numerous different vocabularies and expressions as synonymous and then make models consistent when there is synonym in them. This normalization mechanism allows a certain level of fuzzy processing. For example, by defining parasynonyms and selectively making parasynonyms consistent with each other, fuzzy processing of modeling semantic normalization is realized.
Of course, the implementation of strict normalization process on the model may render subsequent checking of rule compliance situation comparatively rigorous; while over-fuzzy normalization, though makes the checking environment become flexible, sometimes leads to worthless checking results for reference. This calls for an effective balance in the normalization process. Therefore, a better model normalization method is to introduce man-made selection and judgment while using standard vocabulary repository. For example, it may be decided through interaction with human whether to make two parasynonyms consistent or indicate to make two different expressions to be consistent, etc.
Through the above depiction, those skilled in the art can understand that the above-described model normalization processing and its improvements can be realized in a manner which is known in the present art, such as combination of software program and man-machine interface. Thus, details thereof are omitted.
Referring to FIG. 5 , the step (step 103 ) of checking whether compliance rule model is satisfied by business operational model in the flow chart as shown in FIG. 1 is explained in detail by means of the above-described examples of compliance rule model and business operational model. FIG. 5 is a flow chart of checking whether compliance rule model is satisfied by business operational model according to an embodiment of the present invention. The processing flow starts with step 500 . In step 501 , the built compliance rule model and business operational model are loaded via the checking engine.
In step 502 , the loaded compliance rule model is parsed. For example, the compliance rule model may be simplified and rule tree is built, on the basis of the above-mentioned preferable step when building compliance rule model. As described above, the rule tree obtained from the parsed compliance rule model may include three kinds of nodes: concept node, relation predicate node and logical operator node (refer to FIG. 3 ).
In step 503 , all concepts involved in the compliance rule model are located in the business operational model. If it does exist, the corresponding concept on the rule tree is marked with “True”, otherwise, the corresponding concept on the rule tree is marked with “Unknown”. For example, on the rule tree of compliance rule model as shown in FIG. 3 , the concept nodes include: Action “public issuance of securities” 303 and 305 , Purpose “verification and approval or examination and approval” 307 , Principle “law” 309 , Principle “criteria prescribed by laws and administrative regulations” 310 , Organization “securities supervision and administration institution under the State Council” 312 , and Organization “departments authorized by the State Council” 313 .
In the business operational model as shown in FIG. 4 , the aforesaid concept nodes are located one by one. The “Action” concept “public issuance of securities” matches the “Action” attribute of the task node 404 , namely “public issuance of securities”, and thus, the concept nodes 303 and 305 are marked with “True” in the rule tree. As seen above, after implementing the step of model normalization, the Organization “securities supervision and administration institution under the State Council” 312 and the Organization “departments authorized by the State Council” are semantically made consistent to be the Organization “securities regulatory commission”, which match the attribute “Organization” of the task nodes 401 , 402 , 403 , 405 and 406 , namely “securities regulatory commission”, and then, the concept nodes 312 and 313 are marked with “True” on the rule tree. The Purpose “verification and approval or examination and approval” 307 , the Principle “law” 309 and the Principle “criteria prescribed by laws and administrative regulations” 310 do not find the matched attribute items in the business operational model, and then, their nodes are marked with “Unknown”. In this way, all the concept nodes in the compliance rule model are located in the business operational model.
In step 504 , logical operators and relation predicates are calculated. The logical operators include “AND”, “OR” and “NOT”. The calculation result returned value of each logical operation is one of “True”, “False” and “Unknown”. For example, the returned value corresponding to each logical operator may be calculated according to the following tables, where X and Y stand for possible leaf nodes of the logical operator node in the rule tree, respectively.
TABLE 1
the returned values of the logical operator “AND”
Y
AND
True
Unknown
False
X
True
True
Unknown
False
Unknown
Unknown
Unknown
False
False
False
False
False
TABLE 2
the returned values of the logical operator “NOT”
NOT
X
True
False
Unknown
Unknown
False
True
TABLE 3
the returned values of the logical operator “OR”
Y
OR
True
Unknown
False
X
True
True
True
True
Unknown
True
Unknown
Unknown
False
True
Unknown
False
Compared with the calculation of the logical operators, the calculation of the relation predicates is relatively more complicated. Likewise, the calculation result of each relation predicate is one of “True”, “False” and “Unknown”, where: if the checked business operational model satisfies the relation indicated by the relation predicate, then the calculation result is “True”, otherwise the returned value is “False”; if any parameter of the relation predicate is unknown in the current business operational model (i.e., any leaf nodes of the relation predicate is marked with “Unknown” in step 503 ), the calculation result of the relation predicate is also “Unknown”. It can be seen from the above description that, since each predicate stands for a special relation with flexible expression and meaning, unified operation cannot be defined for all predicates. Therefore, it is of necessity to predefine and adopt a different algorithm to calculate its returned value with respect to a different relation predicate.
For example, the values of two leaf concept nodes 312 and 313 of the logical operator “OR” node 311 in the rule tree as shown in FIG. 3 are “True”, and then, the returned value of the node 311 is also “True” in accordance with table 2. The values of two conceptual leaf nodes 309 and 310 of the logical operator “AND” node 306 are “Unknown”, and then, the returned value of the node 306 is also “Unknown” in accordance with table 1. For another example, when processing the predicate node “Action_Action_until” 302 in the rule tree as shown in FIG. 3 , it may be checked in the business process model whether there is the task “submit application for issuance of securities” prior to the task “public issuance of securities”. If there is, the value of the node is “True”; if not the value of the node is “False”. Thereby, the returned values of all the logical operator nodes and predicate nodes in the compliance rule model as shown in FIG. 3 are determined.
In step 505 , it is judged according to the calculation result whether the compliance rule model is satisfied by the business operational model. That is, the returned value of root node is judged in the present embodiment. Similarly, the returned value of the root node is one of “True” indicating that the business operational model is compliant with the compliance rule represented by the compliance rule model, “False” indicating that the business operational model is not compliant with the compliance rule represented by the compliance rule model, and “Unknown” indicating that the compliance situation of the business operational model with respect to the compliance rule is uncertain and more information is needed to make the compliance situation certain.
For example, since the returned values of the two leaf nodes of the root node “IF . . . THEN” 300 in FIG. 3 , namely the relation predicate “Occurrence” node 301 and the relation predicate “Action_Action_until” node 302 , are “True”, the returned value of the root node 300 is also “True”. The processing ends with step 506 .
As how to check and analyze whether the business operational model satisfies the rule tree is explained above, it should be noted that adjustments and improvements can be made to this specific checking mechanism in accordance with users' needs, so as to meet multi-level requirements arising from checking on different compliance rules and businesses. For example, although the above embodiment sets forth only three kinds of returned values, i.e. “True”, “False” and “Unknown”, there may be more returned value types for each node so as to indicate different levels that business operational model complies with the compliance rule model.
Besides the described embodiment, this step (step 103 ) may be implemented using other checking methods known to those skilled in the art. For example, the checking engine utilizes the way, in which semantic parsing program codes semantically parse the compliance rule model and the business operational model, to directly perform semantic match checking so as to obtain a conclusion whether the business operational model satisfies the compliance rule model, etc.
Finally, based on the above checking result, a checking result report on the rule compliance situation is automatically generated and outputted (step 104 ). Such automatic reporting mechanism may be designed to not only support to generate a written text report, but also support to create a multi-level visualized checking report in accordance with the built compliance rule model, business operational model or the combination thereof. Furthermore, users can define different violation and compliance level, which can be reflected in checking report. Of course, it is to be understood that users' flexibility of defining depends on whether a specific checking mechanism supports complex judgment process and can generate more detailed multi-level checking result data.
For example, FIG. 6 depicts a visualized checking report generated based on compliance rule model according to an embodiment of the present invention. As depicted in FIG. 6 , the compliance situation of the business operational model in relation to various relations and logics of the compliance rule in the above embodiment is shown in a form of rule tree, where different graphic symbols are used to exemplarily mark different rule compliance level of each node.
FIG. 7 is a schematic structural block diagram of a system for rule compliance situation checking according to an embodiment of the present invention. In FIG. 7 , reference numeral 700 denotes a system for rule compliance situation checking according to an embodiment of the present invention, reference numeral 701 denotes a business operational model repository, reference numeral 702 denotes a compliance rule model repository, reference numeral 703 denotes normalization means, reference numeral 704 denotes a standard vocabulary repository, reference numeral 705 denotes transformation means, reference numeral 706 denotes compliance rule explanation means, reference numeral 707 denotes a checking engine, and reference numeral 708 denotes reporting means.
As shown in FIG. 7 , users set up a business operational model which is to be checked with business operation modeling tools (not shown), and then store it in the business operational model repository 701 . Also, users set up a compliance rule model with compliance rule modeling tools (not shown) and store it in the compliance rule model repository 702 .
The normalization means 703 semantically normalizes the business operational model to be checked which is in the business operational model repository 701 and the compliance rule model to be checked which is in the compliance rule model repository 702 , using standard vocabularies of a current checking field provided by the standard vocabulary repository 704 . In the system as shown in FIG. 7 , the normalized business operational model and compliance rule model are still stored in the business operational model repository 701 and the compliance rule model repository 702 respectively, so that the normalized models can be used repeatedly.
The normalized business operational model is inputted into the transformation means 705 for formalization processing for the business operational model. Afterwards, the formalized business operational model is inputted into the checking engine 707 .
In the meantime, the normalized compliance rule model is inputted to the compliance rule explanation means 706 for effective simplification and generating a rule tree preferably. Afterwards, the processed compliance rule model is inputted into the checking engine 707 .
It should be pointed out here that, in the checking system as shown in FIG. 7 , although it is after the business operational model and the compliance rule model are normalized by the normalization means 703 that they are respectively inputted to the transformation means 705 and the rule explanation means 706 for processing, those skilled in the art can appreciate that the business operational model and the compliance rule model may be first processed by the transformation means 705 and the rule explanation means 706 respectively and then normalized by the normalization means 703 , just as described above. The processing order and possible connection relations among corresponding means do not constitute restrictions on the present invention.
In the embodiment as shown in FIG. 7 , the checking engine 707 may be the means implementing the processing flow as shown in FIG. 5 , for checking whether the inputted business operational model satisfies the inputted compliance rule model and for inputting the checking data into the reporting means 708 .
According to the checking data reported by the checking engine 707 , and preferably, fewer according to intermediary checking data, the reporting means 708 generates and outputs a checking report. The reporting means 708 can simultaneously support to generate and output a text report and a graphic report.
A structure of a system for rule compliance situation checking is described in conjunction with an embodiment of the present invention. According to other embodiments described above, the system for rule compliance situation checking may have other structures. For example, the normalized business operational model and compliance rule model may be directly inputted into the checking engine, the checking of rule compliance is performed directly by semantically parsing the compliance rule model and the business operational model using semantic parsing program codes. Therefore, the system for rule compliance checking according to the present invention is not limited to the form shown in FIG. 7 .
Part of the present invention may be implemented as a sequence or a group of computer executable instructions (computer software) stored in a computer readable storage medium. The computer readable storage medium may be a non-volatile storage medium such as hardware, read-only memory (ROM) means, CD or DVD optical disk, tape and the like.
As the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and alterations within the scope defined by the claims as appended. | A method for rule compliance situation checking is provided. The method in one aspect, includes the steps of: a) building a rule model for predefined rules and building a business operational model for business processes; b) normalizing vocabularies in the rule model and the business operational model; c) checking whether the rule model is satisfied by the business operational model; and d) outputting a report on checking results. The present invention also provides a corresponding system for rule compliance checking. The rule compliance checking of the present invention allows users to perform fast and effective automatic checking of rule compliance, avoid interference of man-made factors in checking process to a great extent and thus guarantee veracity of checking results. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 12/047,939, filed Mar. 13, 2008, which claims priority to U.S. Provisional Application No. 61/027,965, filed Feb. 12, 2008, the subject matter of which is hereby incorporated by reference in its entirety.
BACKGROUND
Underwriters Laboratories standard 294 (UL 294) entitled “Standard for Access Control System Units Equipment” requires each piece of equipment used for access control to pass a transient voltage test (TVT). Specifically, UL 294 requires an access controller to continue to operate while a 2400V transient voltage is present on any communications cable entering or leaving a room. A 2400V transient voltage far exceeds the limits of an Ethernet communications port. As a result, the TVT requirement of UL 294 restricts devices such as credential readers, door locks, request-to-exit devices, etc. from migrating to TCP/IP without transient voltage protection.
The 2400 TVT applies a 60 ms, 2400V spike between every combination of wires in a cable connecting to an access controller. Due to the proximity of the pins in an Ethernet jack, the 2400V TVT destroys the jack, leaving the access controller inoperable. In order to pass the TVT, an access controller must be able to operate normally during and after the 2400V TVT has been applied. Therefore, there is a need to create a device that has the ability to dissipate a transient while allowing an access controller to operate normally.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments are described below with reference to the attached drawings.
FIG. 1 shows a network topology for protecting network equipment and access controllers from a transient voltage according to one embodiment.
FIG. 2 shows a detailed view of an isolation patch panel according to one embodiment.
FIG. 3 shows a detailed view of the UL 294 protection outlet according to one embodiment.
FIG. 4 illustrates the functionality of the auxiliary contact closure on the isolation patch panel and UL 294 protection outlet according to one embodiment.
DETAILED DESCRIPTION
A method is provided for isolating a segment of a TCP/IP network from transient voltages. In one embodiment, a TCP/IP network is isolated from 2400V transient voltages in compliance with the UL 294 standard. In another embodiment, a method is provided for suppressing a transient voltage both in a network rack containing network equipment such as a network switch and at a remote location, e.g., to satisfy the UL 294 standard.
One embodiment of a network topology for protecting both network equipment and access controllers from a transient voltage is shown in FIG. 1 . As shown, the network equipment includes an isolation patch panel 100 and a network switch 102 . The isolation patch panel 100 is located in a network equipment room 103 . The isolation patch panel 100 protects the network switch 102 . Category 5/6 patch cables 104 connect the network switch 102 and the isolation patch panel 100 .
A UL 294 protection outlet 101 is located near a door 109 , which may be remote from the network equipment room 103 . The UL 294 protection outlet 101 connects an Ethernet Card Reader 106 and the isolation patch panel 100 . The Ethernet Card Reader 106 engages or disengages an electric door lock 108 on the door 109 . The Ethernet Card Reader 106 is also connected to a door contact 111 , which provides data on whether the door 109 is open or closed, and a Request to Exit (REX) device 107 . The UL 294 protection outlet 101 and the Ethernet card reader 106 are connected to the isolation patch panel 100 via a single category 5/6 cable 105 . This topology is compliant with the requirements of UL 294 and provides protection to the network equipment 102 from transient voltages introduced to one of the category 5/6 cables disposed between the door 109 and the isolation patch panel 100 .
FIG. 2 shows a detailed view of the isolation patch panel 220 containing a protection circuit 201 that suppresses the transient voltage across any two wires of a communications cable without damaging communications ports on network equipment (not shown in FIG. 2 ) connected to the isolation patch panel 220 . The isolation patch panel 220 has two connections: an input connection 200 and an output connection 202 . The input connection 200 and output connection 202 may be an RJ 45-type jack 200 or a 110-punch down block-type connector. The input connection 200 and output connection 202 are connected through the protection circuit 201 . The protection circuit 201 provides isolation between the input connection 200 and the output connection 202 using a magnetically coupled, capacitively coupled, or optically isolated circuit. Under normal operation, data passes bi-directionally through the isolation patch panel 100 with no interference. When a transient voltage is present on the horizontal cabling section 205 of the network, the protection circuit 201 diverts the excess voltage to a ground connection 204 of the isolation patch panel 220 . The excess voltage is removed without affecting characteristics of the data communication line (e.g., the category 5/6 cable 105 ), such as impedance, balance, and crosstalk. Consequently, the network switch 102 and access controller (shown in FIG. 4 ) remain in operation while the transient voltage is suppressed. The protection circuit 201 also passes Power over Ethernet (PoE) power from the network switching side 206 to the horizontal cabling side 205 . The network switching side 206 is more proximate to the network switch 102 than the horizontal cabling side 205 .
Referring again to FIG. 1 , the UL 294 protection outlet 101 can be located near the door 109 to protect TCP/IP connections (not shown) locally. The UL 294 protection outlet 101 uses the same protection circuit 201 as the isolation patch panel 100 , but is remotely mounted in a double gang junction box. FIG. 3 shows a detailed view of one embodiment of the UL 294 protection outlet 305 . The UL 294 protection outlet 305 suppresses transient voltages present on an Ethernet Cable 304 from damaging any access controllers connected to the Ethernet Cable 304 through the UL 294 protection outlet 305 . The UL 294 protection outlet 305 includes transient protection and power splitting circuits 303 , an input connection 300 of the RJ 45 or 110-punch down block type, and an RJ 45 jack 301 . If the Ethernet Cable 304 is carrying power via PoE, one or more screw-down type local power and auxiliary contact connections 302 may be present in the UL 294 protection outlet 305 . The local power and auxiliary contact connection 302 is adapted to supply power to a non-PoE enabled device such as the door lock 108 or the request to exit (REX) device 107 (see FIG. 1 ) or a credential reader (e.g., 400 shown in FIG. 4 ). If a transient voltage is present on the Ethernet cable 304 , the transient protection circuit in the transient protection and power splitting circuits 303 discharges the transient voltage to a ground connection (not shown in FIG. 3 ).
Thus, the UL 294 protection outlet in combination with the isolation patch panel provides a means of transmitting an electrical signal, such as an electrical circuit closure, to an access controller across the same network cable carrying data signals and PoE. This functionality allows end users to install auxiliary contact control, data communication, transient voltage suppression and PoE over a single network cable via an isolation patch panel and provide remote connection points at the access controller location.
In the embodiment shown in FIG. 1 , the network switch 102 provides PoE power to the isolation patch panel 100 . The isolation patch panel 100 then passes the power to the UL 294 protection outlet 101 . At the UL 294 protection outlet 101 , circuitry (not shown) de-couples the power from the data signal and provides a termination point (not shown) for PoE power.
In another embodiment shown in FIG. 2 , an auxiliary contact 203 is coupled to the isolation patch panel 220 . The auxiliary contact 203 receives an auxiliary contact electrical signal. The isolation patch panel 220 passes the auxiliary contact electrical signal through the protection circuit 201 to a UL 294 protection outlet (such as UL 294 protection outlet 101 shown in FIG. 1 or UL 294 protection outlet 305 shown in FIG. 3 ) over a single network cable (such as network cable 105 or Ethernet cable 304 shown in FIG. 3 ). At the UL 294 protection outlet, a circuit (not shown) de-couples the auxiliary contact electrical signal from the data and power signals and provides a termination point for auxiliary contact (such as the local power and auxiliary contact connection 302 shown in FIG. 3 ) to the UL 294 protection outlet.
FIG. 4 illustrates the functionality of the auxiliary contact closure on the isolation patch panel 404 and UL 294 protection outlet 410 . In this embodiment, the network equipment room 430 (Room Y) contains the isolation patch panel 404 , a network switch 407 , an access controller 405 , and a Door Unlock Override 403 . The network switch is connected with the access controller 405 . The Door Unlock Override 403 may be a manually activated device such as a button. When the Door Unlock Override 403 is activated, the circuit (e.g., 303 in FIG. 3 ) connected to the auxiliary contact connection (e.g., 302 in FIG. 3 ) on the protection outlet 410 closes, thereby unlocking the door 409 to Room X 420 . The protection circuit (e.g., 204 in FIG. 3 ) in the isolation patch panel 404 passes the electrical signal to the protection outlet 410 via the network cable 406 . At the UL 294 protection outlet 410 , the electrical signal is transmitted through the protection circuit (not shown) in the protection outlet 410 to the auxiliary contact connection (e.g., 302 in FIG. 3 ) in the protection outlet 410 . The electrical signal is then transmitted from the auxiliary contact connection (e.g., 302 ) through the auxiliary override relay connection 401 to the electric door lock 402 . In one embodiment, when the Door Unlock Override 403 closes, the electric door lock 402 engages, thereby locking the door 409 . When the Door Unlock Override 403 opens, the electric door lock 402 disengages, thereby unlocking the door 409 .
In one embodiment of the network of FIG. 4 , UL 294 isolation patch panel 404 is coupled to a network switch 407 , which supplies PoE power to the electric door lock 402 . When the Door Unlock Override 403 engages, the UL 294 isolation panel 404 stops the flow of power to the electric door lock 402 coupled to the UL 294 isolation patch panel 404 , thereby sending the door 409 into its no power position, which is either locked or unlocked. When the Door Unlock Override 403 disengages, power is reconnected to the electric door lock 402 and the electric door lock 402 resumes normal operation. Similarly, a building fire alarm system, or any external electrical contact, can replace the Door Unlock Override 403 . Thus, in another embodiment, a building fire alarm system (not shown) is coupled to the isolation patch panel 404 via a hardwire interconnection. When a fire alarm occurs, the building fire alarm system sends the alarm message to the isolation patch panel 404 via the opening or closing or an electric relay. The isolation patch panel 404 passes the electrical signal through the protection circuit (e.g., 201 in FIG. 2 ) to the UL 294 protection outlet 410 . At the UL 294 protection outlet 410 , the signal is transmitted through the protection circuit (not shown) to the auxiliary contact connection (e.g., 302 ) on the UL 294 protection outlet 410 .
FIG. 4 also shows a TCP/IP credential reader 400 located in or near Room X 420 . The isolation patch panel 404 protects the network switch 407 from a transient voltage. If a credential is presented to the TCP/IP credential reader 400 , the information passes through the protection outlet 410 , through the network cable 406 and the isolation patch panel 404 to the network switch 407 . The information then passes through the network switch 407 to the access controller 405 . If a transient voltage is introduced between the UL 294 protection outlet 410 and the isolation patch panel 404 , the protection circuit (e.g., 201 ) in each device dumps the excess voltage to ground, preventing catastrophic failure of a network port (not shown) on the access controller 405 , the network switch 407 , and any devices connected to the auxiliary contact (e.g., 203 and 302 ) at both the isolation patch panel 404 and the protection outlet 410 . | An access control system dissipates voltage transients while allowing access control equipment to operate normally. The access control system utilizes an isolation patch panel which is provided with circuitry to prevent voltage transients from damaging access control equipment, while also enabling the access control equipment to be wired with standard Ethernet cabling. | 6 |
BACKGROUND
This invention relates to a core for use in a casting mould, and is particularly, although not exclusively, concerned with a ceramic core for use in a mould for casting aerofoil components such as turbine blades and stator vanes of a gas turbine engine.
Stator vanes and blades in turbine stages of a gas turbine engine are commonly provided with internal cavities and passages to allow the flow of cooling air within the component. The blades and vanes may be made by casting, and the cavities and passages may be formed at least partially by positioning a ceramic core within the casting mould. More specifically, such components may be made by a form of investment casting known as the “lost-wax” process. In the lost-wax process, a wax pattern of the component to be cast is formed by injection moulding, around the ceramic core. The wax pattern, including the core, is then dipped into a ceramic slurry, which is then dried. The dipping process is repeated until an adequate thickness of ceramic has been built up, after which the ceramic mould is heated to melt the wax, which is removed from the mould interior. Molten alloy is poured into the mould. When the alloy has solidified, the mould is broken and the ceramic core is removed by leaching to leave the finished cast component.
SUMMARY
Some aerofoil components include a cavity having a narrow region which is formed by a core having a correspondingly thin-walled portion. The thin-walled portion may be perforated, so that, in the casting process, pedestals are formed within the narrow cavity region to support the walls of the component.
The thin-walled portion of the core is very fragile, and consequently the core is prone to breakage in the manufacturing process, either through mishandling or through stresses induced during the moulding of the wax pattern, owing to wax pressures or stresses imparted by the die, or during the casting process itself, owing to molten metal momentum (where it is a metallic material being cast) or to induced strains during casting material cooling.
According to the present invention there is provided a core for use in a casting mould, to form a cavity in a component cast in the mould, the core including a thin-walled portion extending from a thicker portion of the core towards a terminal edge of the core, characterised in that a lateral edge of the thin-walled portion terminates at a bead which is thicker than the thin-walled portion, the bead defining a lateral edge of the core.
The bead serves to reinforce the lateral edge of the thin-walled portion, thus resisting damage to the lateral edge and cracking within the thin-walled portion.
The bead may be one of two beads disposed at opposite lateral edges of the thin-walled portion, both beads defining lateral edges of the core. The lateral edges may be substantially parallel to each other. Alternatively the lateral edges may be at an angle to one another.
The terminal edge of the core may be defined by a rib which is thicker than the thin-walled portion, and which, when two beads are provided at opposite lateral edges, may extend between respective ends of the beads.
The thin-walled portion may be perforated, in which case the perforations may comprise holes which lie on at least one line-extending transversely of the or each lateral edge.
The component to be cast in the mould may include an aerofoil portion including a cavity portion formed by the thin-walled portion.
Another aspect of the present invention provides a cast component having a cavity formed by a core as defined above.
The component may have an external surface which extends generally parallel to an internal surface of a cavity region formed by the thin-walled portion, and to a surface portion of the bead adjacent to the thin-walled portion.
The component may have an aerofoil portion and a shroud portion, the cavity region formed by the bead being situated at the transition from the aerofoil portion to the shroud portion.
The component may be a blade or vane for a gas turbine engine.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: —
FIG. 1 shows a turbine stator vane;
FIG. 2 shows a ceramic core in accordance with the prior art, for use in the manufacture of the vane of FIG. 1 ;
FIG. 3 is a partial sectional view of the core of FIG. 2 taken on the line A-A in FIG. 2 , and of the vane cast using the core;
FIG. 4 corresponds to FIG. 3 but shows a core and vane in accordance with the present invention; and
FIG. 5 corresponds to FIG. 4 , but shows an alternative form of core and vane.
DETAILED DESCRIPTION OF EMBODIMENTS
The vane shown in FIG. 1 comprises an aerofoil portion 2 and inner and outer shroud portions 4 , 6 . The vane has an internal cavity 8 which opens to the exterior at a passage 10 in the shroud portion 6 and a corresponding passage (not visible) in the shroud portion 4 . The cavity 8 also communicates with the exterior through a slot 12 at the trailing edge of the vane. The vane is made from a high temperature aerospace alloy by a lost-wax casting process.
The cavity 8 and the passages 10 are formed in the vane during the casting process by a core 14 shown in FIG. 2 . The core has a main body 16 which forms the cavity 8 , and extensions 18 which form the passages 10 . The body 16 is of generally aerofoil shape, and has a thicker portion 20 , which tapers down to a thin-walled portion 22 , that is to say a portion having a thin cross-section. The thin-walled portion 22 terminates, at a location corresponding to the trailing edge of the vane of FIG. 1 , in a rib 24 which is thicker than the thin-walled portion. The rib 24 serves to form the end of the slot 12 in the cast vane.
The body 20 has lateral edges 26 , which also constitute the lateral edges of the thin-walled portion 22 . The thin-walled portion 22 is perforated by holes 28 . In the cast vane as shown in FIG. 1 , the holes 28 form pedestals 30 which extend between walls 32 , 34 of the aerofoil portion 2 defining the cavity 8 . The holes 28 , in the embodiment shown in FIG. 2 , are disposed in an array constituted by rows of holes lying on lines extending perpendicularly between the lateral edges 26 . As illustrated, one such line is represented by the section line A-A.
FIG. 3 shows, on the left side, a partial section view of the thin-walled portion 22 taken on the section line A-A.
It will be appreciated that the thin-walled portion 22 is fragile, by comparison with the thicker portion 20 of the body 16 and the rib 24 . Furthermore, the perforation by the holes 28 contributes to the weakness of the thin-walled portion 22 . In practice, damage to the core 14 is often initiated by failure at one of the edges 26 of the thin-walled portion 22 , and the crack may propagate into the thin-walled portion 22 , frequently between individual holes 28 , for example along a line of holes extending between the lateral edges 26 .
Cracking of this kind creates a potential path for metal ingress (where a metallic material is being cast) and hence result in casting flash in the cast component. For example, as represented in FIG. 1 , casting flash 36 may form between individual pedestals 30 in the cast vane, these gaps corresponding to cracked regions between adjacent holes 28 in the core 14 .
This flash 36 restricts air flow within the cavity 8 , and can lead to cooling air starvation at the trailing edge of the vane, resulting in local overheating. If detected during inspection of the casting, it may be possible to carry out salvage work to remove accessible flash, but frequently this cannot be performed economically and the component must be rejected. If not detected and remedied there may be premature deterioration of the trailing edge of the aerofoil portion 2 in service.
FIG. 4 shows a modification of the core 14 to avoid damage to the core. A bead 38 is provided along the lateral edge 26 of at least the thinnest part of the thin-walled portion 22 . Being thicker than the thin-walled portion 22 , the bead 38 resists damage, and in particular the initiation of cracks at the lateral edge 26 , and so substantially reduces damage within the thin-walled portion 22 . This minimises the occurrence of regions of flash 36 in the cast component. Consequently, the economic consequences of component rejection and salvage work can be avoided.
The right side of FIG. 4 shows the region of the vane of FIG. 1 corresponding to the core shown on the left side of FIG. 4 . The aerofoil portion 2 merges into the outer shroud portion 6 at a curved transition surface 40 on each side. A bead cavity region 42 , corresponding to the bead 38 , is formed at this transition between the aerofoil portion 2 and the shroud portion 6 , this bead cavity region 42 having a bulbous or “mushroom” shape including diverging surface regions 44 . The corresponding surface regions 46 on the bead 38 are shaped so that the surface regions 44 of the bead cavity region 42 generally follow the curvature of the transition surfaces 40 and preferably are approximately parallel to them. The result is that the rate of change of the wall thickness of the vane at the lateral edges of the cavity is minimised. Preferably, the wall thickness remains generally constant over the inner and outer (or “pressure and suction”) walls 32 and 34 , past the bead cavity region 42 and into the shroud portion 6 . This has advantages in that residual stresses are reduced in the finished component, and stress concentrations during engine operation can be avoided.
An alternative configuration for the bead 38 and the resulting bead cavity region 42 is shown in FIG. 5 . In this embodiment, the bead shape is modified so that the surface regions 44 follow an alternative profile for the transition surface 40 , being more in the form of a truncated teardrop.
Because the bead is situated within the transition between the aerofoil portion 2 and the inner and outer shroud portions 4 , 6 , it does not affect the trailing edge of the aerofoil portion 2 , so that the airflow regime over the vane is not disrupted. Also, the bead 38 is small by comparison with the total flow cross-section over the slot formed by the thin-walled portion 22 of the core 14 . Consequently, the cooling airflow distribution through the slot is substantially unaffected by the bead cavity region 42 . | A core, for use in a casting mould to form a cavity in a cast component such as a blade or vane of a gas turbine engine. The core has a relatively fragile thin-walled region. A bead is formed along a lateral edge of the thin-walled portion in order to reduce cracking or other damage in the thin-walled portion. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a process for foaming and sulfur-curing blends of an ethylene/vinyl ester/carbon monoxide or ethylene/vinyl ester/sulfur dioxide copolymer with a polyvinyl or polyvinylidene halide, such as, for example, polyvinyl chloride or polyvinylidene chloride.
2. Discussion of Related Art
It is known to foam and cure polymers and polymer blends such as, for example, ethylene/vinyl acetate/carbon monoxide terpolymers or blends of such terpolymers with polyvinyl chloride; see, U.S. Pat. Nos. 4,370,423 and 4,391,923, both to Rys-Sikora. Curing of the foamable polymer compositions of those patents is accomplished by means of free radicals. Those compositions, therefore, contain free radical generators, such as peroxides, peresters, or azides.
It also is known to foam and sulfur-cure diene elastomers such as, for example, natural rubber, SBR, and similar materials. Foams made by such processes are readily available commercially.
Further, it is known to sulfur-cure ethylene/vinyl acetate/carbon monoxide (E/VA/CO) terpolymers, as described in U.S. Pat. No. 4,172,939 to Hoh.
Foaming and curing polymer blends in the manner described in the above-cited Rys-Sikora U.S. Pat. No. 4,391,923 has certain shortcomings. Firstly, free radicals are sensitive to, and are destroyed by, oxygen. As a result, foaming and curing cannot be carried out in the presence of air, for example, in an oven, but normally would be carried out by compression molding, in the absence of air. This, in turn, makes it impossible to produce cured foams by a continuous process, where the composition is at the same time foamed and cured in an oven or a heat tunnel. A second drawback of the free-radical cures is that free radicals are easily consumed by various conventional compounding ingredients, such as, for example, antioxidants, certain extending oils, and plasticizers, and thus quickly become depleted, leaving the composition uncured or only partially cured. Such conventional compounding ingredients are, therefore, often omitted from those compositions.
It is, therefore, desirable to be able to produce foams of such polymer blends by a process which would not suffer from those limitations.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a process for producing, a foamed, cured composition comprising a polymer blend of
(1) 5 to 95 parts of a copolymer E/X/Y, wherein
E is ethylene;
X is a vinyl ester; and
Y is carbon monoxide or sulfur dioxide;
and
(2) 95 to 5 parts of a polymer of a vinyl halide or vinylidene halide, the total amount of polymers (1) plus (2) being 100 parts;
said process comprising: (A) uniformly dispersing in said polymer blend an effective amount of a blowing agent and at least one curing agent selected from
(a) about 0.2 to 5 parts of sulfur and (b) about 0.2 to 15 parts of an agent capable of releasing elemental sulfur under the cure conditions; and
(B) heating said blend containing the blowing agent and the curing agent at a temperature of about 100°-180° C., at which both foaming and curing take place, for a sufficient time to obtain substantially complete foaming and curing.
There also is provided a foamed and cured composition produced by the above process.
DETAILED DESCRIPTION OF THE INVENTION
The E/X/Y copolymers used in the present invention either are available commercially or can be made according to published information. The vinyl ester comonomer X can be, for example, vinyl acetate, vinyl propionate, vinyl butyrate etc., but the most commonplace comonomer, vinyl acetate, is preferred. An ethylene/vinyl acetate/carbon monoxide terpolymer is available from the assignee of this invention under the trademark Elvaloy®. The polymer can be made according to the procedures described in U.S. Pat. No. 3,780,140 to Hammer and U.S. Pat. No. 2,495,286 to Brubaker. Other copolymers, in which X is another vinyl ester, can be prepared in the same manner. Sulfur dioxide-containing copolymers can be made by the process of U.S. Pat. No. 3,684,778 to Hammer.
These copolymers can also contain a fourth comonomer, which can be, for example, an ethylenically unsaturated carboxylic acid (for example, acrylic or methacrylic acid), an ester of such an acid, acrylonitrile, or an α-olefin.
The vinyl halide polymer can be, for example, polyvinyl chloride or polyvinyl bromide; and the vinylidene halide polymer can be, for example, polyvinylidene chloride or polyvinylidene bromide. Polyvinyl chloride is commercially available from many sources, including Conoco, Inc., while polyvinylidene chloride is available, for example, from Dow Chemical Co. Other polymers of those types can be made as described, for example, in Encyclopedia of PVC, edited by L. J. Nass, Marcel Dekker, Inc. New York (1976).
The vulcanizing agent that is added to, and dispersed in, the polymer blend is one of those normally employed in the vulcanization of rubber and can be elemental sulfur or a compound that releases sulfur at vulcanization temperatures, i.e., a sulfur donor, or mixtures thereof, which compounds are well known in the industry. Extensive descriptions of sulfur vulcanizing systems that can be used in this invention have been published, for example, in Hofmann, "Vulcanization and Vulcanizing Agents", Palmerton Pub. Co., N.Y. 1967; and Alliger and Sjothun, "Vulcanization of Elastomers", Reinhold Pub. Corp., N.Y., 1964. Representative vulcanizing agents that release sulfur at vulcanization temperatures include thiuram polysulfides, e.g., dipentamethylene thiuram tetrasulfide or hexasulfide, tetramethyl thiuram disulfide; amine disulfides, e.g., di-morpholyl disulfide; sodium polysulfide, and thioplasts. When the temperature of the terpolymer is increased during vulcanization, the sulfur donors liberate part of their loosely bound sulfur which is then consumed in the formation of crosslinks.
Organic accelerators can be, and generally are, used in combination with the vulcanizing agent and dispersed throughout the polymer blend in order to shorten the vulcanization times and lower curing temperatures. Further, the amount of vulcanizing agent can be reduced when a curing accelerator is used. Any conventional accelerator or mixtures thereof normally used to vulcanize rubber can be used in the present invention including: the thiazoles; mercapto accelerators such as mercaptobenzothiazole; and sulphenamide accelerators, e.g., derivatives of mercaptobenzothiazole; guanidine accelerators, e.g., diphenylguanidine (DPG) and di-o-tolylguanidine (DOTG); thiurams, such as thiuram monosulfides and thiuram disulfides; and dithiocarbamates. The amount of accelerator used can vary over a wide range and the amount depends on the particular chemical composition, the accelerator and the intended use of the elastomer. Generally, the amount of accelerator used will be about 0.2-4, preferably 0.5-2 parts, per 100 parts of polymer blend.
Fillers, processing aids, plasticizers, and oils can be added if desired. Among the fillers that can be used, carbon black, calcium carbonate, talc, magnesium oxide, and zinc oxide can be mentioned as quite commonplace in the rubber industry. Zinc oxide also serves as an activator for axodicarbonamide when the latter is used as a blowing agent.
Organic plasticizers of the types used in plasticizing polyvinyl chloride can be used in E/VA/CO terpolymer/polyvinyl chloride blends. Suitable plasticizers include, for example, aryl phosphates such as triphenyl phosphate, phthalate esters such as dioctyl phthalate and tributyl phthalate, trimellitate esters such as tri(2-ethylhexyl)trimellitate, and adipate esters such as diisodecyl adipate. Also see "the Technology of Plasticizers" by J. Kern Sears and Joseph R. Darby, John Wiley and Sons, Pub. (1982). The amount of plasticizer depends on the end use and the stiffness appropriate for the end use, but it preferably should not exceed the level of polyvinyl chloride present in the compositions.
The polymers, fillers, and plasticizers can be mixed in a batch mixer, such as a Banbury mixer, or a continuous mixer, such as a Farrell continuous mixer, at a suitable temperature, usually about 160°-200° C., preferably 165°-175° C. The temperature should be adequate to facilitate mixing but not so high as to cause polymer discoloration or degradation.
The blowing agent, activator, curing agent, and accelerator can be added to the blend on a roll mill, usually at a roll temperature in the range of 50°-130° C. Usually, these materials are not added all at once but gradually, over a period of several minutes. The roll temperature is chosen so as to avoid both premature curing of the polymer blend and decomposition of the blowing agent during the blending operation. The appropriate temperature thus will depend, among others, on the activities of the blowing and curing systems used as well as on the composition and the softening temperature of the blend.
Curing and foaming are carried out simultaneously within a temperature range of about 100° to 180° C. This can be done, for example, in a circulating oven, a salt bath, a hot air tunnel, or another heating arrangement.
The operation can be either batchwise or continuous. When it is continuous, a completly compounded polymer blend composition containing both the curing and the foaming agents, as well as any accelerators and activators, is continuously extruded into the heating zone at a rate such that both foaming and curing are substantially complete at the time the composition leaves the heating zone; the cured material is cooled to ambient temperature, cut into appropriate lengths, if necessary, and removed to a storage area. In a batch operation, one or a series of compression molds are filled with the completely compounded composition and heated to an appropriate temperature for a suitable time to adequately crosslink the polymer and decompose the blowing agent; the mold is then opened and expansion of the foam occurs.
This invention is now illustrated by the following examples of certain representative embodiments thereof, where all parts, proportions and percentages are by weight, unless indicated otherwise. "PVC" stands for polyvinyl chloride. All measurements made and results obtained in units other than SI have been converted to SI units.
EXAMPLE 1
A stabilized polymer blend was prepared as follows:
______________________________________Blend Components %______________________________________PVC (Firestone FPC-9300), inh. visc. = 0.96 46.3Mark S17, phosphite chelator (Argus Chem. Co.) 0.5Ba/Cd laurate (Argus Chem. Co.) 1.4Acryloid ® K-120N 1.4acrylic fusion aid (Rohm & Haas)Allied 617A (polyethylene wax) 1.8Epoxidized soybean oil 4.6Calcium carbonate 11.6E/VA/CO (65:25:10) terpolymer, 32.4melt index = 20______________________________________
The blend was made in two steps. First, all ingredients except the E/VA/CO terpolymer were combined in a high speed dry blender (Welex). This dry blend was then added to a Banbury internal mixer, along with the E/VA/CO terpolymer, and was mixed at high speed for 10-15 minutes at a temperature of 190° C. This material is referred to as polymer blend A.
Four foamable and curable compositions designated a, b, c, and d were prepared by intimately mixing all ingredients on a two-roll rubber mill operating at a temperature below the decomposition temperature of the chemical blowing agent, about 120° C. They were then foamed and cured in a press at 165° C. and a force of 188,000 N.
Compounding and curing information as well as the physical properties of the resulting foams are summarized in Table 1 below.
TABLE 1______________________________________Components %______________________________________Polymer Blend A 64.3 81.5 85.9 74.1Carbon Black (ASTM-N650) 25.7 6.1 -- 18.1Carbon Black (ASTM-N-762) -- -- 6.4 --Azodicarbonamide 2.6 4.0 3.0 2.5Zinc Oxide 1.3 1.2 2.1 0.8Pentaerythritol; -- 2.0 0.9 1.2particle size 0.075 mmStearic Acid 0.6 0.6 0.2 0.4Zinc Stearate 1.3 1.2 -- 0.7Sulfur 0.6 0.6 0.9 0.4Thiocarbanilide, sulfur 0.2 0.2 -- 0.1cocurativeMercaptobenzothiazole 0.3 0.3 -- 0.2Zinc dibutyl dithiocar- 0.6 0.6 -- 0.4bamateDesical P (80% CaO in 1.9 1.8 -- 1.1hydrocarbon oil),Basic Chemical Co.Tellurium diethyl 0.2 0.2 -- 0.1thiocarbamateTetramethylthiuram mono- -- -- 0.1 --sulfideN--cyclohexyl-2-benzo- -- -- 0.4 --thiazole sulfenamideCure time, min. 7.0 9.0* 7.0 12Density, g/cm.sup.3 0.67 0.26 0.23 0.96Hardness, Durometer A 84 31 29 57(ASTM D2240-81)Bashore rebound, % -- 15 14 13(ASTM D2632-67)______________________________________ *Plus 60 min postcure in oven at 160° C.
EXAMPLE 2
The stabilized and plasticized polymer blend used in this example was prepared in the manner described in Example 1 from the following components and is referred to as polymer blend B.
______________________________________Polymer Blend B %______________________________________PVC (Firestone FPC-9300), inh. visc. = 0.96 43.82Phosphite chelator (Argus Chem. Co.) 0.22Ba/Cd laurate (Argus Chem. Co.) 1.10Epoxidized soybean oil 2.19Stearic acid 0.09Dioctyl phthalate 35.06E/VA/CO (65:25:10) terpolymer, 15.34melt index = 20______________________________________
The composition was prepared in two stages using a two-roll rubber mill. The ingredients of part I of the formulation shown in Table 2, below, were blended at a temperature of 150° C. The mill was then allowed to cool to 110° C. and the ingredients of part II of the formulation shown in Table 2 were blended in at that temperature. The curing conditions and physical properties of foams resulting from these compositions also are shown in Table 2.
TABLE 2______________________________________ a b______________________________________Part IPolymer Blend B 67.10 66.73Calcium Carbonate 16.77 16.68Satintone Special Clay 6.71 6.67(Engelhardt)Zinc Oxide 2.68 2.67Stearic Acid 1.34 1.33Part IIAzodicarbonamide 3.35 3.33Sulfur 0.94 0.93N--cyclohexyl-2-benzo- 0.67 0.67thiazole sulfenamideMercaptobenzothi- 0.34 0.33azoleTetramethyl- 0.13 0.13thiuram monosulfidePentaerythritol -- 0.50______________________________________Cure conditions and foam properties Composi- Composition a tion b______________________________________press cure time at 6 -- 6 5 6165° C., min.post-cure time in -- 6* 10 5 --oven at 170° C., min.density g/cm.sup.3 0.81 0.72 0.63 0.31 0.21Shore A hardness 50 40 49 20 10______________________________________ *Sample was cut from uncured sheet produced on roll mill and placed directly in an oven at 170° C. to afford a cured, free blown (no compression) foam.
EXAMPLE 3
This example illustrates the preparation of a filled, sulfur-cured, low density, closed cell foam by extrusion and continuous oven cure.
The stabilized polymer blend used in this example had the following composition:
______________________________________Polymer Blend C Parts______________________________________PVC (Conoco grade 5305, inherent 40viscosity, 0.75)Mark XX (liquid phosphite chelator, 1.5Argus)Mark XI (Ba/Cd laurate stabilizer, Argus) 3Epoxidized soybean oil 6(Rohm & Haas)Allied 6A (polyethylene processing aid, 6Allied)E/VA/CO (66:24:10) Terpolymer 60(melt index 35)______________________________________
All of the ingredients in Blend C, except the E/VA/CO terpolymer, were first blended in a high speed mixer (Welex) in 3000 g batches. The dry blend was then placed in a lined drum along with the terpolymer, and the blend was tumble-blended on a drum tumbler. The resulting blend was melt-extruded using a 28 mm single screw extruder operated at 220 rpm with the barrel temperature set at 180°-200° C. and the die temperature at about 220°-230° C.
Polymer C was further compounded as follows:
______________________________________ a b______________________________________Polymer Blend C 894 894Hydrated amorphous 44.7 44.7silica (Hardwick)Calcium carbonate 268.2 268.2Dimethylnaphthalene/ 89.4 89.4formaldehyde resinCalcium stearate 8.94 8.94Stearic Acid 4.5 4.5Titanium dioxide 44.7 44.7Adipic acid 4.5 4.5Zinc Oxide 22.4 22.4Chlorinated paraffin 44.7 44.7oil (Diamond Shamrock)Calcium oxide 22.4 22.4Magnesium carbonate 89.4 89.4Diethylene glycol 8.94 8.94TE 80 (Processing aid, 8.94 8.94Technical Processing Co.)Isodecyl diphenyl 44.7 89.4phosphate______________________________________
Polymer Blend C, in pelletized form, was charged to a Banbury mixer and melted, whereupon the other ingredients listed above were added, and mixing was continued at 165° C. for 10 minutes. Each blend was then discharged and rolled into a sheet on a roll mill. These materials are referred to as Banbury compounds.
The Banbury compounds were blended with a blowing agent, a blowing agent accelerator, and sulfur curing agents on a roll mill set at 80° C.
The milled compound was taken off the roll as sheets which were cut into strips and fed into a 3.75 cm Royale single screw extruder equipped with a vacuum screw with an L/D ratio of 15 and a streamlined 1.25 cm diameter circular while die and extruded at a melt temperature of about 100° C. The smooth extruded rod was cured in a tunnel with two heating zones, 140° C. and 154° C., with a residence time of 8 minutes in each zone. A soft foam with a smooth outer skin and having a density of 0.16 gm/cm 3 was obtained.
EXAMPLE 4
The formulations shown here exhibit greatly improved ozone resistance over nitrile rubber/PVC foams:
TABLE 2______________________________________ g %______________________________________Part IEVACO (65.5:23.5:11) terpolymer 66.0 23.8PVC (Inherent viscosity 0.93) 27.2 9.9Ba/Cd Laurate 0.8 0.3Phosphite Chelator (Argus Chem. Co.) 0.3 0.1Epoxidized soybean oil 2.7 1.0Polyethylene Wax (Allied 617A) 5.1 1.8Stearic Acid 2.1 0.8Acrylic Processing Aid 0.8 0.3(Acryloid ® K120, Rohm & Haas)Titanium dioxide 70.0 25.3Hydrated Alumina 30.0 10.8Carbon Black (ASTM N550 FEF) 10.0 3.6Zinc Oxide 4.0 1.4Tricresyl Phosphate 15.0 5.4Dioctyl Phthalate 20.0 7.2Part IISurface-Treated Urea (Uniroyal) 1.5 0.5Azodicarbonamide 18.0 6.5Sulfur 1.4 0.5N--cyclohexyl-2-benzo- 1.0 0.4thiazole sulfenamideMercaptobenzothiazole 0.5 0.2Tetramethylthiuram monosulfide 0.5 0.2 276.9 100.0______________________________________
PVC, stabilizers, and processing aids (Ba/Cd laurate through Acryloid® K120 in Table 2) were combined in a high intensity mixer (Welex); then the other ingredients of Part I were combined in a Banbury mixer at 180° C. for 10-15 minutes.
On a roll mill, Part I and Part II were combined at a maximum temperature of about 120° C.
Foams were made by compression molding at 165° C. for 3-5 minutes followed by an oven cure of 9-10 minutes at 170° C.
OZONE DEGRADATION
Samples of a commercial nitrile rubber-PVC foam were compared with the above E/VA/CO-PVC foam in a static ozone exposure test. Ozone concentration was 3 ppm at 37.8° C. Samples 2.5 cm wide, 1.25 cm thick, and 15 cm long were attached at one end and bent over a 5 cm mandrel; a weight was affixed to the free end. Samples were observed after exposure to the ozone, and both failure and failure time were recorded. Samples were checked daily except on weekends. Therefore, a time range is recorded for time to break.
______________________________________ Hours to Break______________________________________Nitrile-PVC foam 47-119Nitrile-PVC foam 23-47E/VA/CO-PVC foam No break after 1879 hours. Test terminated.______________________________________
EXAMPLE 5
The following blends were prepared
______________________________________ Parts______________________________________Part IPVC (Firestone FPC-9300) 26.8Ba/Cd Laurate (Argus Chem Co.) 0.8Phosphite Chelator 0.3(Argus Chem Co.)Epoxidized soybean oil 2.6Dioctyl phthalate 8.0Polyethylene wax (Allied 6A) 1.0Stearic Acid 0.1Acryloid ® K-120N (Rohm & Haas) 0.8E/VA/CO (65:25:10) terpolymer 59.5Talc 70Clay 40Zinc Oxide 4Stearic Acid 2Part IIAzodicarbonamide 18Surface-treated urea (Uniroyal) 1.52-Mercaptobenzothiazole 0.5Sulfur 1.4N--Cyclohexyl-2-benzothiazole 1sulfenamideTetramethylthiuram monosulfide 0.2Carbon Black (ASTM N- 650) 1______________________________________
PROCEDURE
Part I ingredients were blended in a Banbury internal mixer for 10 min. at 160° C. Ingredients of Part II were blended with the Part I blend on a two-roll rubber mill at 50° C.
The above composition was fed to a single screw intruder operating at 88° C., exiting through a ribbon die into a 6-meter air-heated tunnel with an air temperature of 175° C. The rate of feed was controlled so that the total residence time in the tunnel was 7.5 min. The resulting closed-cell foam had a density of 0.39 g/cm 3 . | A blend of an E/X/Y copolymer, where E is ethylene, X is a vinyl ester, and Y is carbon monoxide or sulfur dioxide, with a polymer of vinyl halide or vinylidene halide is foamed and cured by dispersing in the blend a blowing agent and sulfur or a sulfur-releasing agent and heating the blend containing those additives at 100°-180° C. for a sufficient time to produce curing and foaming. This process can be run either continuously or batchwise in conventional equipment under conventional conditions in the presence of air. Plasticizers and other materials which often interfere with peroxide cures can be present in the process of this invention. The foamed and cured products have excellent physical properties and ozone resistance. | 2 |
This is a division of U.S. patent application Ser. No. 10/278,296 entitled “THREADING ARM ASSEMBLY FOR A PAPER MACHINE”, filed Oct. 23, 2002.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to paper machines, and, more particularly, to devices for threading a fiber web tail in a paper machine.
2. Description of the Related Art
During startup of a paper machine, or following a web break, a narrow edge strip of the fiber web (called a tail) is typically guided along a web travel path through the dry end of the machine. Blast nozzles pointing in the machine direction may be used to transfer the tail through the machine. The air jets produced by the blast nozzles drive the tail in the desired direction through the machine. This process is known as “threading ”the machine.
It is known to provide a rope guide arrangement whereby two points converge in a so called rope nip at the beginning of the rope guide arrangement. The tail is led into the rope nip which is located in a pick up area and is held between the ropes. The tail is carried together with the ropes along the web travel path into a transfer area in which the tail is transferred to a downstream unit in the machine.
Occasionally, the tail may not align with the rope nip defined by the rope guide arrangement. It is sometimes necessary to manually feed the tail into the rope nip for threading of the machine. Not only is this time consuming, but it is also desirable to avoid inserting hands and arms into the machine area whenever possible.
What is needed in the art is a device which not only threads a fiber web tail in a machine direction, but also is capable of diverting the fiber web tail in a direction transverse to the machine direction.
SUMMARY OF THE INVENTION
The present invention provides a threading arm assembly which diverts a fiber web tail laterally (with respect to the machine direction).
The invention comprises, in one form thereof a paper machine for manufacturing a fiber web traveling in a machine direction and having a tail. At least one rope defines a rope nip. A threading arm assembly is positioned in association with the rope nip. The threading arm assembly includes a frame and a diverter carried by the frame. The diverter is movable to divert the tail in a direction transverse to the machine direction toward the rope nip.
The invention comprises, in another form thereof a threading arm assembly for threading a fiber web tail. The threading arm assembly includes a frame having a mounting, and a diverter carried by the frame. The diverter is movable generally toward the mounting for diverting the fiber web tail generally toward the mounting.
An advantage of the present invention is that the fiber web tail can be diverted laterally into a rope nip associated with a dryer section.
Another advantage is that the diverter can be provided with an air cushion so as not to directly contact the fiber web tail.
Yet another advantage is that the diverter can be operated either manually or automatically.
Still another advantage is that the threading arm assembly of the present invention can be retrofitted to existing machines.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view of an embodiment of a threading arm assembly of the present invention;
FIG. 2 is a side view of the threading arm assembly of FIG. 1 ;
FIG. 3 is a side view of another embodiment of a threading arm assembly of the present invention;
FIG. 4 is a side view of the threading arm assembly of FIG. 3 with the diverter in a pivoted position;
FIG. 5 is a side view of vet another embodiment of a threading arm assembly of the present invention;
FIG. 6 is a schematic view of a portion of a paper machine, showing relative placement of a threading arm assembly of the present invention; and
FIG. 7 is a schematic view of a portion of another paper machine, showing relative placement of a threading arm assembly of the present invention.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIGS. 1 and 2 , there is shown an embodiment of a threading arm assembly 10 of the present invention used for threading a fiber web tail in a paper machine. Threading arm assembly 10 is positioned in association with a rope nip, such as associated with a drying section in the paper machine, for threading the fiber web tail into the rope nip. Threading arm assembly 10 generally includes a frame 12 , elongate member 14 , diverter 16 and air assist tube 18 .
Frame 12 is positioned along a side of the paper machine and attached to any suitable structure. Frame 12 includes a mounting 20 in the form of a plate with mounting holes therein. Mounting 20 allows threading arm assembly 10 to be mounted to new paper machinery or retrofitted to existing paper machinery. Other types of mountings are of course also possible, depending upon the particular application.
Elongate member 14 is in the form of a cylindrical tube which is carried by frame 12 . Cylindrical tube 14 is both longitudinally moveable as well as rotatable relative to frame 12 . A handle 22 is attached to cylindrical tube 14 to manually slide and rotate tube 14 relative to frame 12 . An adjustable stopper 24 is attached to tube 14 and limits manual movement of tube 14 relative to frame 12 .
An adjustable plate assembly 26 is attached to the distal end of cylindrical tube 14 . Plate assembly 26 includes a first plate 28 attached to cylindrical tube 14 , and a second plate 30 adjustably attached to first plate 28 . Suitable fasteners, such as bolts (not show), are placed within the slotted openings formed in each of first plate 28 and second plate 30 to provide adjustability therebetween.
Diverter 16 is connected with second plate 30 using adjustable bushings 32 providing both longitudinal as well as rotational adjustability. Diverter 16 is placed at a desired orientation within bushings 32 , and locked into place such as with set screws or the like.
Diverter 16 has a generally C-shaped cross section. Diverter 16 also has a hollow interior which is in fluid communication with a plurality of air discharge holes 34 at the inner portion of the C-shaped cross section. Air discharge holes 34 generally face toward frame 12 . The hollow interior portion of diverter 16 is fluidly connected with hollow tube 14 by a fluid line 36 , which in turn is connected with a source of pressurized air at the opposite thereof (not shown).
Air assist tube 18 is also carried by frame 12 , and includes a plurality of air discharge holes 38 . When in an operating position as shown in FIG. 2 , fiber web tail 40 passes between cylindrical tube 14 and air assist tube 18 , and moves from left to right as indicated by arrow 42 . Air assist tube 18 is coupled with a suitable source of pressurized air, such as the same source to which cylindrical tube 14 is coupled.
During periods of inoperation, cylindrical tube 14 is rotated and retracted such that diverter 16 is rotated upwards and retracted to a position adjacent frame 12 so as not to interfere with operation of the traveling fiber web. If it becomes necessary to thread a fiber web tail, the tail is passed over air assist tube 18 and is urged in the machine direction by the plurality of air discharge holes 38 therein. Cylindrical tube 14 is manually slid to an extended position with handle 22 , and rotated downwardly such that diverter 16 is adjacent to the distal end of air assist tube 18 . Cylindrical tube 14 is positioned such that the side edge of the fiber web tail passes generally through the inner C-shaped portion of diverter 16 . Handle 22 is then pulled in an axial direction to cause diverter 16 to move toward the edge of the fiber web tail. Continued retraction of cylindrical tube 14 and diverter 16 moves the fiber web tail in the transverse direction with respect to the machine or running direction 42 .
Referring now to FIGS. 3 and 4 , there is shown another embodiment of a threading arm assembly 50 of the present invention. In the embodiment shown in FIGS. 3 and 4 , fiber web tail 40 is traveling in a direction perpendicular to the drawing page. Threading arm assembly 50 , like threading arm assembly 10 shown in FIGS. 1 and 2 , moves fiber web tail 40 in a transverse direction with respect to the running or machine direction. However, rather than using a C-shaped diverter with an air cushion as shown in FIG. 1 , threading arm assembly 50 includes a pivot arm 62 which pivots as shown by arrow 52 in FIG. 4 , thereby causing movement of fiber web tail 40 in a direction transverse to the machine direction as indicated by arrow 54 .
More particularly, threading arm assembly 50 includes a mounting 56 which is pivotally coupled with a pivot linkage 58 at pivot pin 60 . Pivot arm 62 has a pre-selected length and is in threaded engagement with pivot linkage 58 . Pivot linkage 58 has a generally L-shaped configuration, with the free end being coupled with a pneumatic cylinder 64 . Pneumatic cylinder 64 is a two way cylinder in the embodiment shown, which is either manually or remotely actuatable. Pneumatic cylinder 64 is of course fluidly coupled with a source of pressurized air (not shown).
FIG. 5 illustrates yet another embodiment of a threading arm assembly 70 of the present invention. Similar to the embodiment of threading arm, assembly 50 shown in FIGS. 3 and 4 . threading arm assembly 70 shown in FIG. 5 has a pivot arm 72 which is pneumatically actuated. However, rather than pivoting in an upward direction as shown in the embodiment of threading arm assembly 50 , pivot arm 72 pivots in a downward direction to move the fiber web tail in a transverse direction with respect to the running direction into ropes 74 . Pivot arm 72 may also pivot in an upward direction, depending on the specific application.
More particularly, threading arm assembly 70 includes a frame 76 which is pivotally coupled with pivot arm 72 at pivot pin 78 . A pneumatic cylinder 80 is also carried by frame 76 . Pneumatic cylinder 80 is a single action, spring loaded air cylinder which pivots pivot arm 72 in a downward direction as shown by phantom line 82 when actuated. An internal spring biases pivot arm 72 to the position shown when pneumatic cylinder 80 is in a non-actuated state.
Stroke cylinder 84 is a pneumatic cylinder which moves frame 76 and pivot arm 72 between operable and non-operable positions. Stroke cylinder 84 is a 2-way cylinder having a guide member 86 which extends therefrom. Frame 76 is coupled with the distal end of ram 90 within stroke cylinder 84 . Guide pin 88 extending from frame 76 extends through an opening formed in guide member 86 , and maintains the relative positioning between frame 76 and stroke cylinder 84 during extension and retraction of ram 90 . Stroke cylinder 84 is coupled with and carried by suitable structure on the paper machine, such as a frame member, etc.
FIG. 6 is a schematic view of a portion of a paper machine 100 , showing relative placement of a threading arm assembly 102 of the present invention. Threading arm assembly 102 could be any of threading arm assemblies 10 , 50 or 70 described above, depending upon the particular application. Paper machine 100 includes a press assembly 104 and a dryer cylinder 106 . Press assembly 104 includes two press rolls defining a nip therebetween. A felt 108 passes through the press nip formed by press assembly 104 between the two roles, and carries fiber web tail 110 . Fiber web tail 110 passes over threading arm assembly 102 and thus it is assumed that threading arm assembly 102 is configured as threading arm assembly 10 or threading arm assembly 50 described above. It will be appreciated, however, that threading arm assembly 102 may likewise be positioned above tail 110 , in which case it may take the form of threading arm assembly 70 . Regardless of the particular configuration, threading arm assembly 102 moves tail 110 in a transverse direction with respect to machine direction 112 to thread tail 110 into ropes 114 and 116 .
FIG. 7 is a schematic view of a portion of another embodiment of a paper machine 120 , showing relative placement of a threading arm assembly 122 . Paper machine 120 includes a center press roll 124 , vacuum box 126 , baby dryer cylinder 128 , felt 130 and ropes 132 , 134 . Again, threading arm assembly 122 may take the form of threading arm assembly 10 , 50 or 70 , depending upon the particular application. Threading arm assembly 122 diverts the fiber web tail in a transverse direction with respect to machine direction 136 into the nip formed between ropes 132 and 134 .
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | A method of threading a fiber web tail movable in a machine direction, comprising the steps of: positioning a threading arm assembly in association with a rope nip, the threading arm assembly including a frame and a diverter carried by and movable relative to the frame; diverting the tail using the threading arm assembly in a direction transverse to the machine direction toward the rope nip; and threading the diverted fiber web tail into said rope nip. | 3 |
FIELD OF THE INVENTION
The present invention relates to a flow rate control valve, and more particularly, to a proportional solenoid operated valve having a shielded armature motion sensing feature.
BACKGROUND OF THE INVENTION
Solenoid valves have been conventionally used to control the flow rate of a fluid by using a solenoid to control valve activation. A conventional solenoid valve has a magnetic sensor, which is typically a Hall effect sensor, that effectively senses movement of a component and thus provides positional information for a moving component positioned in high pressure fluid in a fluid delivery device.
The Hall effect sensor used in motion sensing can offer enhanced reliability in extreme environments. A coil contained in the solenoid valve produces an electromagnetic field that may interfere with the accurate performances of the Hall effect sensor, but the prior art, such as Fukano et al., U.S. Pat. No. 6,666,429, does not have any protective mechanism to prevent external electromagnetic fields from interfering with the Hall effect sensor.
It is an object of the invention to provide a shield made of an appropriate protective material so that the performance characteristics of the Hall effect sensor are not compromised by external electromagnetic fields created by the solenoid coil.
SUMMARY OF THE INVENTION
The invention is directed to a shielded solenoid for a solenoid operated valve having a solenoid body and an annular coil of electrical wire in the solenoid body which has a central hole therethrough. A first hollow magnetic pole piece is oriented in the central hole adjacent a first axial end face of the annular coil. A second hollow magnetic pole piece is coaxially oriented with respect to the first pole piece in the central hole adjacent a second axial end face of the annular coil remote from the first axial end face and being magnetically isolated from and immovably fixed with respect to the first pole piece. An end of the second hollow pole piece has a non-magnetic plug member closing an open end thereat. An armature of magnetic material is rectilinearly movably displaceably mounted in the first and second hollow magnetic pole pieces. A non-magnetic rod part projects coaxially from at least one axially facing end thereof and is rectilinearly movable with the armature. The non-magnetic rod part has a magnet holder fastened thereto and has a permanent magnet fixedly oriented thereon. A hollow metallic shield member covers a segment of an outer periphery of the second pole piece whereat the magnet holder and the permanent magnet are oriented. The shield member is configured to shield a Hall effect sensor from any significant electromagnetic field produced by the coil when effecting rectilinear movement of the armature. The hollow shield member has a non-metallic plug closing one end thereof. The plug has the Hall effect sensor oriented therein to closely oppose the magnet on the magnet holder so that movement of the armature and resulting corresponding movement of the magnet will cause the Hall effect sensor to produce a signal indicative of movement of the armature.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and purposes of this invention will be apparent to persons acquainted with apparatus of this general type upon reading the following specification and inspecting the accompanying drawing, in which:
FIG. 1 illustrates a central, longitudinal cross sectional view of the proportional solenoid valve with a motion sensor in accordance with an embodiment of the invention; and
FIG. 2 is a fragmentary view of a modified shield member.
DETAILED DESCRIPTION
The solenoid portion 10 of a solenoid operated valve is illustrated in the drawing. The solenoid portion 10 includes a solenoid body 11 having a hollow cylindrical, non-metallic bobbin 12 on which is wound many turns of wire 13 to form an annular coil 14 .
The annular coil 14 is encased in a non-metallic synthetic resin shell 15 which has a radially outwardly extending flange 16 having a plug socket 17 formed therein so that electrical contact prongs 17 A are exposed in the socket for electrical connection to a plug not shown. The contact prongs 17 A are electrically connected to the wire 13 forming the annular coil 14 so as to facilitate the provision of electrical energy to the coil 14 .
In this particular embodiment, the shell 15 is oriented inside a steel cup 18 having a through-hole 20 in the bottom wall 19 thereof and with the flange 16 projecting through a slot 18 A in the rim of the open end of the cup 18 . The shell 15 is retained inside the steel cup 18 by press fitting a washer 18 B into the open end of the steel cup. In this particular embodiment, a compressible spring o-ring type seal 18 C is oriented between the washer 18 B and the shell 15 .
A first elongate hollow tubular magnetic pole piece 21 has an externally thread end section 21 A configured to screw into an internally threaded hole in a valve body not shown. The other end of the pole piece 21 is fixedly oriented inside the interior of the hollow bobbin 12 .
In this particular embodiment, the first pole piece 21 extends into the interior of the bobbin 12 a finite distance. A second elongate hollow tubular magnetic pole piece 22 is coaxially oriented with respect to and secured by an also coaxially oriented non-magnetic member 24 , and oriented about the mid-portion of the hollow interior of the bobbin 12 , to an end of the first pole piece 21 that is remote from the valve body. The second pole piece 22 extends a finite distance beyond the end of the bobbin 12 that is remote from the valve body and through and beyond the hole 20 in the bottom wall 19 of the steel cup 18 . It is beneficial for the clearance dimension between the inner diameter surface of the hole 20 and an outer diameter surface 23 of the pole piece 22 to be as small as is reasonable for assembly in order to optimize the magnetic shielding.
A non-magnetic, here brass, hollow plug 25 is secured to the open end of the second pole piece 22 by any convenient structure. Here, the plug 25 has a reduced diameter portion 26 receives therein the crimped open end 27 of the second pole piece 22 . In addition, the portion of the plug 25 extending axially beyond the pole piece 22 has an external thread 28 thereon, the purpose of which will be explained in more detail below. The axially facing end wall 25 A of the hollow plug 25 has a shallow centrally oriented recess 25 B therein, the purpose of which will be explained in more detail below.
A hollow armature 29 made of magnetic material is rectilinearly movably and displaceably mounted internally of the pole pieces 21 and 22 . A non-magnetic rod 31 extends through the interior of the armature 29 and is secured as by being pressed fit therein. Other forms of securement of the rod 31 to the armature 29 are to be considered as being within the scope of this invention.
In this particular embodiment, the rod 31 extends axially beyond both ends of the armature 29 . The end 32 of the rod 31 extends through the interior of the pole piece 21 and is operatively connected to a movable valve member (not illustrated) inside the valve body for controlling the flow of fluid through the valve body in a well understood way. The opposite end 33 of the rod 31 has a magnet holder 34 fixedly secured thereto and movable therewith.
In this particular embodiment, the magnet holder 34 has an opening in one end 35 into which the distal end 33 of the rod 31 is pressed fit. The opposite end 36 of the magnet holder 34 has an axially opening cup shaped opening 37 therein into which is fixedly oriented a permanent magnet 39 . In this particular embodiment, the outer diameter of the magnet holder 34 is conformed to the hollow interior of the plug 25 so as to be relatively movably and slidably received therein.
The hollow interior 30 of the armature 29 at an end from which the end 33 of the rod 31 extends is enlarged and is configured to attach to the magnet holder 34 . The attachment of the magnet holder 34 to the armature 29 can be formed by being pressed fit or by using a threaded connection. The magnet holder 34 also has a radially outwardly extending flange 38 thereon that is configured to abut against the end of the plug 25 oriented inside the pole piece 22 .
A hollow steel cylindrical shield member 40 having an internal thread 41 thereon oriented mid-length of the shield member 40 is threadedly secured to the external thread 28 on the plug 25 . The interior surface 40 A of the shield member 40 on one side of the internal thread 41 has a diameter closely conforming to the external diameter surface 23 of the second pole piece 22 so as to facilitate the interior part 42 of the shield member 40 snuggly sliding over the exterior surface 23 of the second pole piece 22 . A reduction of the clearance dimension between the outer diameter surface 23 and the inner diameter surface 40 A to as small as is reasonable for assembly is important for the purpose of optimizing the magnet shielding.
A synthetic resin plug 43 having a Hall effect sensor 47 encased therein is slidably received into an open end of the shield member 40 on a side of the internal thread 41 remote from the interior part 42 .
In this particular embodiment, the Hall effect sensor 47 is oriented at one end of the plug 43 close to an axially facing flat surface 44 of the plug 43 that opposes the shallow recess 25 B in the end wall 25 A of the plug 25 . The circumferential periphery of the plug 43 adjacent an end remote from the Hall effect sensor 47 has a reduced diameter section 45 forming a shoulder 46 onto which is provided a compressible spring 48 .
A cup shaped cap 49 having a central through-hole 50 in the bottom wall 51 through which extends the reduced diameter section 45 of the plug 43 is secured to the end of the steel shield member 40 . The segment of the bottom wall 51 surrounding the through-hole 50 serves as an abutment for the end of the compressible spring 48 that is oriented remote from the end abutting the shoulder 46 .
The compressible spring 48 initially urges the plug 43 into engagement with the shoulder 46 . However, as the internal thread 41 of the shield member 40 is threaded onto the external thread 28 of the plug 25 , the flat surface 44 of the plug 43 will abut the end face of the wall 25 A of the plug 25 in the area radially outside the shallow recess 25 B so that any forces developed during the engagement will not cause harmful mechanical stress to be applied to the Hall effect sensor 47 during assembly. A continued rotation of the shield member 40 to effect the aforesaid threaded engagement of the threads 28 and 41 will cause a relative axial movement of the shield member 40 toward the bottom wall of the steel cup 18 and a compression of the spring 48 until the shield member 40 abuts the surface of the bottom wall of the steel cup 18 . A continued rotation of the shield member 40 will cause an urging of the steel cup 18 toward the valve body (not illustrated) until the washer 15 B tightly abuts against a shoulder 21 B on the pole piece 21 . Thus, the single step of screwing the shield member 40 onto the threads 28 causes a proper orienting of the Hall effect sensor 47 with respect to the magnet 39 and a locking of the annular coil 14 in the proper position on the valve body and with respect to the pole pieces 21 and 22 .
A rubber o-ring 52 can, if desired, be provided between the shield member 40 and the bottom wall of the steel cup 18 . On the other hand, the rubber o-ring 52 can be replaced with a metal seal ring 52 A configured to wedge into contact with the shield member 40 , the bottom wall 19 of the steel cup 18 and the surface 23 of the pole piece 22 in order to optimize the magnetic shielding. In addition, a hollow or split steel ring 53 can be provided in the region of the crimped portion 27 of the pole piece 22 and configured to contact the pole piece 22 and the shield member 40 in order to enhance the magnetic shielding. The ring 53 does not need to completely encircle the aforesaid structure.
The Hall effect sensor 47 has a plurality of wires connected in a conventional way to it, and they extend through the synthetic resin plug 43 in a conventional way and exit the plug 43 in the form of a socket 53 having plural prongs 54 therein to which each respective wire is attached to facilitate the reception of a plug member (not illustrated) that can be received to connect the prongs to electrically conductive sockets provided on the plug.
The magnetic shielding for the aforesaid structure can be further enhanced by modifying the shield member 40 to include three components as shown in FIG. 2 . More specifically, the modified shield member 40 B includes a steel shield member 40 C comparable to the steel shield member 40 described above and which has the internal thread 41 thereon. Surrounding the steel shield member 40 C is a non-magnetic material 40 D which in turn is surrounded by a further steel shield member 40 E. The non-magnetic material 40 D serves to isolate the steel shield member 40 C from the steel shield member 40 E. The modified shield member 40 B combined with the hollow or split steel ring 53 and the steel seal ring 52 A and the close tolerance fit of the steel shield member 40 B to the surface 23 on the pole piece 22 and the close tolerance fit of the surface 23 on the pole piece 22 in the hole 20 provides a very effective magnetic shield isolating the effects of the magnetic field from the operating coil on the Hall effect sensor 47 .
The shield member 40 is configured to shield the Hall effect sensor 47 from any significant electromagnetic field produced by said coil 14 during periods of activation causing rectilinear movement of the armature 29 .
Although a particular preferred embodiment of the invention has been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie with the scope of the present invention. | A shielded solenoid for a solenoid operated valve having a solenoid body and an annular coil of electrical wire in the solenoid body. An armature of magnetic material is rectilinearly movable with respect to the body. A magnet holder is fastened to the armature and has a permanent magnet fixedly oriented thereon. A shield member covers the magnet holder and the permanent magnet. The shield member is configured to shield a Hall effect sensor from any significant electromagnetic field produced by the coil when effecting rectilinear movement of the armature. The hollow shield member has a non-metallic plug closing one end thereof. The plug has the Hall effect sensor oriented therein to closely oppose the magnet on the magnet holder so that movement of the armature and resulting corresponding movement of the magnet will cause the Hall effect sensor to produce a signal indicative of movement of the armature. | 5 |
FIELD OF THE INVENTION
The invention relates to mixing methods and apparatus in which two substances are conveyed and mixed. In particular, the substances can be sewage sludge and a flocculant such as a polymer. The invention is particularly concerned with a method and apparatus by which the substances are mixed while being conveyed and wherein pipe elbows are employed to effect the mixing and conveyance.
PRIOR ART
It is well known to convey fluids through pipes and to employ pipe elbows in the hydraulic circuit through which mixing of substances in the fluid will take place.
U.S. Pat. No. 2,025,974 (Fritz) discloses a mixing nozzle inclusive of a plurality of bend portions. The mixing passage is of zig-zag formation to provide a tortuous path for the material travelling therethrough.
U.S. Pat. No. 2,213,640 (Stone) shows a mixing structure in FIGS. 5 and 10 which is comparable to that in the aforesaid Fritz Patent.
U.S. Pat. No. 2,862,522 (Yost) discloses means for inducing spiraling movement of liquid passing through a pipe.
U.S. Pat. No. 2,889,174 (Schwing) discloses equipment for conveying pulpy or plastic materials and in FIG. 12 discloses a pipeline which is given a profiled section to cause revolution of a concrete plug passing through the pipe.
U.S. Pat. No. 3,719,207 (Takeda) discloses a helical protrusion on the internal surface of a pipe causing fluid in the pipe to rotate about the longitudinal axis of the pipe.
U.S. Pat. No. 3,779,519 (Anderson et al) shows a conical mixer in FIGS. 4 and 5 in which mixing is effected by a vortex action. This patent is also relevant for the disclosure of a pipe system having pipe elbows therein.
U.S. Pat. No. 3,847,184 (God) discloses a pipe for conveyance of a fluid along a nonlinear path with alternating cylindrical and flexible portions along its length to enable the pipe to be shaped into a nonlinear configuration along the flexible portions.
SUMMARY OF THE INVENTION
An object of the invention is to provide mixing apparatus which utilizes pipe elbows in a particular configuration to effect mixing of substances passing through the elbows.
A further object of the invention is to employ the pipe elbows in such a way as to produce rotation of the substances passing through the elbows to effect such mixing.
A further object of the invention is to utilize the pipe elbows as the sole means to effect the mixing of the conveyed substances.
Another object is to provide mixing apparatus which effects rotational circulation of the substances to be mixed without any internal vanes, paddles or other mixing means. Thereby, no unfavorable accumulation of solids will be produced.
Yet another object of the invention is to dispose the elbows such as to convey the substances to be mixed from an upper level to a lower level. In this way, flow and mixing can be assisted by the effects of gravity.
A specific object of the invention is to provide mixing apparatus utilizing pipe elbows in which sewage sludge can be mixed with a flocculant such as a polymer.
In order to achieve the above and other objects of the invention, there is provided a plurality of pipe elbows connected one after the other and through which first and second substances travel and undergo mixing, said pipe elbows having bend angles which are successively turned in different directions to lie out of a common plane and cause the mixture to rotate as it travels through the elbows. Hence, each axial streamline of the mixture in the cross-sectional flow path at an inlet end is angularly rotated in the cross-sectional flow path at the outlet end.
In a constructional arrangement which represents a feature of the invention, the pipe elbows are right angle elbows and are arranged in groups of three whose center lines are disposed in mutually perpendicular planes. The inlet and outlet of the assembled three elbows are disposed in parallel planes but are axially offset from one another. In the course of travel through the three elbows, the mixture is rotated through an angle of 90°. By assembling four sets of three elbow units, the mixture can be rotated through 360°. Furthermore, by using an even number of elbow units, the outlet of the assembly can be made to be aligned coaxially with the inlet.
It is a further object of the invention to provide a method of mixing two substances by causing the substances to flow along a path of travel defined by the pipe elbows as recited above. In this way the substances are turned through successive bend angles while traveling along the path of flow and undergo rotation in the flow cross-section.
In a specific aspect of the method of the invention, the substances to be mixed are turned through successive bend angles in different planes which are mutually at right angles to one another.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is a perspective view of a mixing apparatus according to the invention.
FIG. 2 is a side elevational view of the mixing apparatus.
FIG. 3 is a top plan view of the mixing apparatus.
FIG. 4 is a front elevational view of the mixing apparatus.
FIG. 5 is a diagrammatic sectional view taken along line 5--5 in FIG. 1.
FIG. 6 is a diagrammatic sectional view taken along line 6--6 in FIG. 1.
FIG. 7 is a diagrammatic sectional view taken along line 7--7 in FIG. 1.
FIG. 8 is a sectional view on enlarged scale showing a coupling arrangement between the ends of two pipe elbows.
DETAILED DESCRIPTION
Referring to FIGS. 1-4, therein is seen a mixing apparatus 10 which is composed of a plurality of identical pipe elbows 11-16. Each of the pipe elbows has a right angle bend and, therefore, has respective open ends which lie in perpendicular planes. Although six pipe elbows have been shown, it will be seen that the mixing apparatus can include more or less than this number.
Basically, the mixing apparatus is composed of a succession of pipe elements which are connected in groups of three. Thus, pipe elbows 11-13 in group 20 are arranged so that their center lines lie in mutually perpendicular planes, i.e., in planes which are perpendicular to one another. Similarly, the pipe elbows 14-16 of group 21 have center lines which lie in mutually perpendicular planes.
The mixing apparatus 10 has an inlet 22 and an outlet 23 and in the arrangement of the pipe elbows as shown, the inlet and outlet are coaxially arranged wherein the inlet 22 is at a level above the outlet 23. At the inlet 22 the substances to be mixed are introduced and in the particular circumstances of the construction, it is contemplated that sludge and flocculant will be introduced at inlet 22 so as to be mixed in the course of its travel through the pipe elbows to be discharged as a flocculated sludge. As shown, the sludge and flocculant are introduced axially although it is equally possible for the flocculant to be introduced laterally in an optional arrangement.
As shown in FIG. 1, the pipe elbows are arranged in vertical array with the inlet 22 at a level about the outlet 23 whereby mixing will be assisted by the effect of gravity in the downward flow of the substances. However, it is not necessary for the pipe elbows to be vertically arranged and the mixing effect will take place in any position of the pipe elbows.
Heretofore, it has been the conventional practice to introduce the sludge and flocculant into a mixer which controls the rate of flow of the sludge and flocculant. Since the mixing apparatus 10 of the invention employs pipe elbows which serve to convey the sludge and flocculant, there is effectively no substantial detention time which controls the rate of feed of the sludge and flocculant. Moreover, the need for special mixing apparatus is obviated. The pipe elbows of the mixing apparatus can be constructed of any suitable material such as metal, plastic and the like.
Next will be considered the pattern of flow of the sludge and flocculant as it travels through the three elbows 11-13 of group 20. This will be typical of the flow pattern through each group of three elbows.
The mixture flows from the inlet 22 of elbow 11 and travels along a path in which the bend lies in a vertical plane. The mixture then passes into elbow 12 where the bend lies in a horizontal plane. Thereafter the mixture then flows through elbow 13 where the mixture travels in a vertical plane at right angles to the vertical plane through the center line of elbow 11. Thus, the mixture travels through successive elbows 11-13 whose center lines are located in planes which are mutually perpendicular to one another. As a consequence of this course of travel, the streamlines of the flow path are successively lengthened and shortened causing changes of velocities of the streamlines to produce a mixing operation. Furthermore, each of the streamlines undergoes a rotation of 90° in travelling from the inlet of elbow 11 to the outlet of elbow 13. In this regard, the streamline designated at 25 in FIG. 5 is located at a position at the outlet of elbow 13 which is displaced 90° in the clockwise direction. The orientation of the streamline along elbows 11,12 and 13 is shown in chain-dotted outlines in FIGS. 1-4. In the course of travel through the three elbows 14-16 of group 21, the streamlines each undergo a further rotation of 90° as shown by streamline 25 in FIG. 7. Hence, there is 180° rotation of the flow cross-section in its transport from inlet 22 to inlet 23. If a further succession of groups are attached at 23 for successive conveyance of the mixture, the flow cross-section can be made to rotate through greater angles. When four groups of three elbows are employed, the flow cross-section undergoes a 360° rotation. Furthermore, it is evident that the inlet at the top of the mixing apparatus 10 can be brought into axial alignment with the outlet at the bottom of the mixing apparatus when an even number of groups of three pipe elbows are utilized. In this regard, it should be noted that in each group, the inlet and outlet will lie in planes which are parallel to one another but axially offset.
In order to enable each group to be connected to a successive group, the inlet and outlet ends of each group will be formed to enable a quick connection and release. An assembly is shown in FIG. 8 where the inlet end of elbow 14 is connected to the outlet end of elbow 13. Herein it can be seen that the outlet end of elbow 13 has a flared end 30 in which an O-ring seal 31 is supported in its interior surface. A circumferential slot 32 is formed within the inner surface of end 30. The inlet of elbow 14 is formed as a male end 33 which is of tapering conical shape for insertion into the end 30 of elbow 13. The end 33 is provided with bayonet portions 34 which fit into circumferential slot 32 via axial slots 35 corresponding in number and placement to bayonet portions 34. Connection is made by inserting the end 33 of elbow 14 into the end 30 of elbow 13 to seal the two ends by seal 31 and elbow 14 is then rotated to lock the bayonet portions 33 in the slot 32.
Although the invention has been described in relation to the mixing of two substances introduced separately at the inlet of the mixing apparatus, it is equally possible to introduce a single fluid substance at the inlet which is to undergo mixing as it travels through the pipe elbows.
DESCRIPTION OF PARTICULAR EMBODIMENTS
In a particular embodiment, the invention is employed to mix a polymer with a liquid sludge. The sludge has a solids concentration of 0.1 to 22% and is fed at a rate between 25 and 200 gpm. A polymer solution of a flocculant having a dry solids concentration of 0.05-2% is fed at a rate between 1 and 15% volumetrically of the feed rate of the sludge. The sludge and flocculant solutions pass through a vertical array of 12 pipe elbows consisting of four groups of elbows each with three elbows arranged in mutually perpendicular relation. At the outlet of the elbows, the sludge and flocculant are thoroughly and uniformly mixed. Each of the pipe elbows is composed of PVC and has a pipe diameter between two and three inches. The pipe elbows are 90° long sweep elbows and in each group are adhesively joined at their ends to form a smooth, unbroken, inner passageway without vanes, paddles, grooves, etc. Each group of three elbows is connected to the next by means of flanges which are secured to the end elbows and are bolted together. The flanges serve as a connect and release means for each of the groups of three elbows.
The mixture of sludge and flocculant is fed to an aging vessel in which the mixture has a detention time of the order of one to three minutes. The effectiveness of the mixing of the sludge and polymer in the pipe elbow mixing apparatus is indicated by the degree of flocculation of the sludge which is discharged from the aging vessel. With the pipe elbow mixing apparatus of the invention, it is found that the degree of flocculation is substantially complete and is at least as great as that obtained by using complex and expensive mixing apparatus.
When other substances are to be mixed or a single substance is to undergo mixing or agitation, it may be possible to use more or less numbers of groups of three pipe elbows.
The use of three elbows in each unit has the further advantage that cleaning of each unit can be easily effected from both of the unit ends over 11/2 bends. This can be achieved by brushes or other suitable means.
Although the invention has been described in relation to a specific embodiment thereof, it will become apparent to those skilled in the art that numerous modifications and variations can be made within the spirit and scope of the invention as defined in the attached claims. | A mixing apparatus and associated method comprising a system for supplying a first substance of liquid constitution and a system for supplying a second substance to an assembly of pipe elbows to effect mixing and transport of the substances along the assembly. The pipe elbows are right angle elbows connected one after the other in groups of three. Each group has an inlet and an outlet disposed in parallel planes and axially offset from one another. The pipe elbows in each group have center lines disposed in mutually perpendicular planes to cause the mixture to rotate as it travels along the pipe elbows. | 8 |
FIELD OF THE INVENTION
This invention relates to gas cleaners to remove moisture, dust and other foreign matters from gases, and more particularly to gas cleaners suited for removing moisture, dust and other foreign matters from various kinds of gases to be introduced into chambers to produce extra- or super-high vacuum or various kinds of process gases.
DESCRIPTION OF THE PRIOR ART
When lowering the vacuum pressure in a container, gas molecules carried at the surface of or occluded in the container are liberated into the space therein when the pressure has dropped to 10 -4 to 10 -5 torr, thereby inhibiting the further drop of the pressure. Baking is an artificial measure to quickly release such unwanted gases by heating the container.
The description speed of many gases, such as H 2 , O 2 and CH 4 , at ordinary temperature (20° C.) is between 10 -12 and 10 -13 sec. That of H 2 O is of the order of 10 -6 sec. At 150° C., the desorption speed of H 2 O decreases to the order of 10 -8 sec., whereas that of other gases, such as H 2 O 2 and CH 4 , remains substantially the same. Therefore, baking is effective for quickly liberating H 2 O from the surface of the container, but the effect of baking is not so significant as the case of H 2 O for other gases.
To quickly lower the vacuum pressure in a chamber or other space, therefore, it is necessary to minimize the moisture content therein. It should be noted that at ordinary temperature the chamber wall carries an approximately 10 6 times greater amount of H 2 O than H 2 , O 2 , CH 4 and other gases. Therefore it takes about 10 6 times longer time for H 2 O to reach from the chamber wall to a discharge pump. This clearly shows how it is important to reduce the moisture content to a minimum. Accordingly, supplying gases of low moisture content to vacuum containers is effective for their quick evacuation. For example, gases (such as air) supplied to evacuated chambers whose pressure level should be either left as evacuated or returned to atmospheric must be dehumidified.
In an experiment the inventors conducted, it took about 800 minutes to evacuate a chamber to 10 -8 torr after filling it with air of 45 percent humidity. The time was reduced to about 120 minutes when the chamber was filled with a gas containing 10 to 20 ppm of moisutre, and further to about 11 minutes with a dehumidified gas (to below the 1 ppm limit measurable with a commercially available measuring instrument).
Elimination of H 2 O is also essential in the production of semiconductors in a vacuum because H 2 O decomposes into H 2 and O 2 , with the result that O 2 combines with silicon wafers to form SiO 2 that impairs the high purity required of the products. But it is usually very difficult to avoid the mixing of H 2 O during the transportation of gases from their makers to the point of their use. Therefore it becomes indispensable to always keep H 2 O out of the chambers where extra- or super-high vacuum is produced or some specific type of work, such as the production of semiconductors, is carried out.
Porous adsorbents, known as the molecular sieve, filled in sorption pumps and cooled with liquid nitrogen or other coolants have conventionally been used for the adsorption and removal of moisture, dust, impurities and unwanted gases to avoid the entering of moisture, dust and other foreign substances into the chambers in which extra- or super-high vacuum is produced, or surface analysis (particularly one done in a vacuum) or production of semiconductors is carried out. The molecular sieve is made of an artificially prepared highly adsorptive zeolite which adsorbs more gases when cooled to lower temperature and releases the adsorbed gases when heated.
But the removal of moisture with molecular sieves involves the following problem. Molecular sieves hardly adsorb the molecules of gases whose diameter is larger than that of their own pores. In other words, the gases adsorbed by molecular sieves are mostly limited to those whose molecule's diameter is smaller than the diameter of their own pores. Therefore, molecular sieves adsorbs even necessary gases if their molecules are smaller than their pores. As such, their use is limited to certain applications. Because of their poor heat conductivity, in addition, their temperature, when cooled with liquid nitrogen, does not fall below more than 100° C. above the temperature of liquid nitrogen (-195.8° C.) in two hours. This means that the intended work cannot be started promptly. As such, molecular sieves, though they are known to be useful in various applications, are not effective in the removal of moisture described above.
SUMMARY OF THE INVENTION
An object of this invention is to provide a gas cleaner that is capable of efficiently removing unwanted moisture and dust without adsorbing the necessary gases.
Another object of this invention is to provide a gas cleaner having a filter of a sintered metal of good enough heat conductivity to get readily cooled at the start of operation to bring the cleaner into a working condition in a short time so that the intended work can be started promptly.
Still another object of this invention is to provide a gas cleaner having a filter of a sintered metal of good enough heat conductivity to permit an efficient temperature drop that results in the enhancement of the adsorption efficiency.
Yet another object of this invention is to provide a gas cleaner that permits easy temperature control of the coolant.
A further object of this invention is to provide a gas cleaner having a filter encased in a hermetically sealed container, with part of the container placed in a case whose temperature can be readily controlled so that the liquefaction of gases in the hermetically sealed container can be prevented by application of heating as required.
In order to achieve the above objects, the gas cleaners according to this invention comprise a heat-insulating coolant container to hold a coolant, a hermetically sealed container of a thermally conductive material to be immersed in the coolant held in the coolant container, the hermetically sealed container having a pipe to supply a gas to be cleaned, a pipe to discharge a cleaned gas and a multi-stage filter of a sintered metal to remove moisture by cooling and adsorbing the gas flowing from the supply pipe to the discharge pipe therein and the multi-stage filter being made of a sintered metal prepared by sintering fine particles or fibers of a thermally conductive metal and directly fitted to the inner wall of the hermetically sealed container.
When the liquefying temperature of the gas to be cleaned is identical or analogous to the temperature of the coolant, the gas to be cleaned may liquefy in the hermetically sealed container without flowing to the discharge pipe. In such cases, therefore, a heat-insulating coolant container to hold a coolant, a case to pass a temperature control fluid and a hermetically sealed container of a thermally conductive material extending over both of the coolant container and case are provided. While the gas inlet side of the hermetically sealed container is placed in the case, the gas outlet side is encased in the coolant container. While the filter on the gas inlet side is positioned in that portion of the hermetically sealed container which is placed in said case, the other filters are placed in the portion thereof in the coolant container.
The gas cleaners of this invention may also comprise a pipe to supply a primary coolant, a heat-insulating coolant container to be filled with a secondary coolant that is cooled by the primary coolant to a temperature near the freezing point thereof, and a thermally conductive hermetically sealed container immersed in the coolant in the coolant container. The hermetically sealed container has a pipe to supply a gas to be cleaned, a pipe to discharge the cleaned gas and a multi-stage filter of a sintered metal to remove moisture by cooling and adsorbing the gas flowing from the supply pipe to the discharge pipe therein and the multi-stage filter being made of a sintered metal prepared by sintering fine particles or fibers of a thermally conductive metal and directly fitted to the inner wall of the hermetically sealed container.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional front view of a first preferred embodiment of this invention.
FIG. 2 is a cross-sectional front view of a second preferred embodiment of this invention.
FIG. 3 is a cross-sectional front view of a third preferred embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a first preferred embodiment of this invention. A gas cleaner 1 comprises a heat-insulating coolant container 3 to be filled with a coolant 2, such as liquid nitrogen and Freon, and a hermetically sealed container 4 immersed in the coolant 2. A supply pipe 5 and a discharge pipe 6 to send a gas to be cleaned into and a cleaned gas out of the hermetically sealed container 4 extend outside the gas cleaner 1 through the holes provided in a heat-insulating cover 7 of the coolant container 3.
The hermetically sealed container 4 is made of a thermally conductive material, such as stainless steel and aluminum alloys. Filters 9a, 9b and 9c are disposed in the direction substantially perpendicular to the direction of the gas flow. The filters are joined together so that a good thermal conductivity is maintained by fastening them closely to the inner walls of the container 4. The filters are made by sintering fine particles, fibers or composites thereof of a thermally conductive metal, such as stainless steel and brass. The filters are formed to have such meshes as are close to the mean free path of the gas to be cleaned. For ease of manufacturing, the particles or fibers may be put together with pores of the order of a few μm left therebetween to allow the passage of the fluid. But it is desirable to reduce the size of the pores to below 1 μm (preferably to about 0.1 μm). It is also preferable to make the pores in the successive filters progressively finer from the coarser one 9a on the inlet side toward the finer one 9c on the outlet side. It is particularly preferable for the filter on the inlet side, which adsorbs a large quantity of moisture, to have coarser pores.
The hermetically sealed container 4 contains a heater 10 that heats the atmosphere under a high vacuum by passing a heating fluid before the cleaning of the gas starts, thereby sufficiently releasing the moisture within the container.
When a coolant 2, such as liquid nitrogen, is filled in the coolant container 3, the temperature in the hermetically sealed container drops rapidly from the periphery thereof toward the center of the filters 9a, 9b and 9c. Made of a material having a good thermal conductivity, the filters 9a, 9b and 9c cool faster than the aforementioned molecular sieve, thus permitting gas cleaning to be started in a shorter time.
When the filters 9a, 9b and 9c have been fully cooled, a gas to be cooled is supplied through the supply pipe 5. The gas flows through the filters 9a, 9b and 9c to the discharge pipe 6, whereby the coolant 2 liquefies and adsorbs gases (vapors) of impurities that evaporate at higher temperatures than the coolant 2. After the impurity gases, moisture and dust have been removed by the filters 9a, 9b and 9c, a cleaned gas flows outside through the discharge pipe 6. The lower the temperature, the greater the amount of molecules adsorbed. Therefore, the high thermal conductivity of the filters 9a, 9b and 9c helps enhance the efficiency of adsorption. The gas to be cleaned passes through the pores of the filters 9a, 9b and 9c that are as fine as only a few microns several hundred times. Therefore, the filters catch more gas molecules because their probability of colliding the inner wall of the filters is high. Being not so porous as the molecular sieve, the filters permit increasing the flow rate of the gas, without adsorbing necessary components.
The filters made of stainless steel can be used for the dehumidification and dust removal of corrosive gases.
The gas cleaner just described is of the type in which the removed impurities and dusts are accumulated. When continuous gas cleaning is desired, therefore, two or more units of the same gas cleaner must be prepared. Then, while one is at work, the hermatically sealed container 4 of another unit is heated by the heater 10, with its inside dehumidified and cleaned by means of a vacuum pump. The high thermal conductivity of the filters 9a, 9b and 9c again permits quick heating and fast dehumidification of the hermetically sealed container 4.
The first preferred embodiment just described is of an overall cooling type that cools the entirety of the hermetically sealed container 4. When the liquefaction temperature of the coolant 2 and the gas to be cooled is the same or analogous, as in cleaning nitrogen gas with liquid nitrogen, the gas (e.g., nitrogen gas) may not flow to the discharge pipe 6, liquefying within the hermetically sealed container 4. When the coolant 2 in the coolant container 3 runs out, the liquefied gas in the hermetically sealed container 4 may vaporize to push up the pressure therein to an extremely high level.
FIG. 2 shows a second preferred embodiment of this invention whose hermetically sealed container is partially cooled to overcome the above problem.
A gas cleaner 21 comprises a heat-insulating coolant container 23 to be filled with a coolant 22, a heat-insulating case 31 placed below the coolant container 23, and a hermetically sealed container 24 in which gas is cleaned. The gas inlet side 24a of the container 24 is placed in the case 31 and the gas outlet side 24b in the coolant container 23. A filter 29a on the gas supply side is positioned in the case 31 that has an inlet 32 to admit air or other gases and an outlet 33. Filters 29b and 29c are positioned in the coolant container 23. A pipe 25 to supply a gas to be cleaned and a pipe 26 to discharge a cleaned gas extend outside the cleaner 21 through the holes 27 provided in the case 31 and a heat-insulating cover 27 of the coolant container 23.
The gas cleaner 21 has a temperature control unit that heats the gas inlet side 24a of the hermetically sealed container 24 by forcibly passing air or other gases from the inlet 32 to the outlet 33. Thus, the liquefaction of gases within the hermetically sealed container 24 can be prevented by actuating the temperature control unit as required.
Even when the gas to be cleaned has liquefied at the filters 29b and 29c, the resulting liquid drops onto the filter 29a and vaporizes. Therefore, the gas within the hermetically sealed container 24 always remains unliquefied.
Reference numeral 30 designates a heater whose construction and function are as described previously with reference to the first preferred embodiment of this invention.
FIG. 3 shows a third preferred embodiment of this invention. A gas cleaner 41 comprises a pipe 51 to supply a primary coolant leading into a heat-insulating coolant container 43 filled with a secondary coolant 42. A hermetically sealed container 44 to which a pipe 45 to supply a gas to be cleaned and a pipe 46 to discharge a cleaned gas are connected is immersed in the secondary coolant 42 in the coolant container 43. The pipe 51, supply pipe 45 and discharge pipe 46 extend outside the cleaner 41 through the holes provided in a heat-insulating cover 47 of the coolant container 43. A temperature sensor 52 is installed in the coolant container 43, which is connected to a controller 53 that controls the supply of the primary coolant from a supply unit 54 to the pipe 51 according to the output of the temperature sensor 52.
While liquid nitrogen may be used as the primary coolant, the secondary coolant is chosen from among coolants having higher freezing point, such as ethanol. The secondary coolant is cooled by the primary coolant to a temperature slightly lower than the freezing point thereof.
The hermetically sealed container 44 is made of a thermally conductive material as in the first preferred embodiment. Filters 49a, 49b and 49c disposed substantially at right angles to the direction of the gas flow are closely fitted to the inner wall of the container 44 to keep a high thermal conductivity. The filters are made, as in the first preferred embodiment, by sintering fine particles, fibers or composites thereof of a thermally conductive metal, such as stainless steel and brass. The filters are formed to have such meshes as are close to the mean free path of the gas to be cleaned. It is preferable to make the pores in the successive filters progressively finer from the coarser one 49a on the inlet side toward the finer one 49c on the outlet side. It is particularly preferable for the filter on the inlet side, which adsorbs a large quantity of moisture, to have coarser pores. The hermetically sealed container 44 contains a heater 50 that heats the atmosphere under a high vacuum before cleaning starts, thereby sufficiently releasing the moisture within the container.
The primary coolant supplied from the primary coolant supply unit 54 to the pipe 51 cools the secondary coolant 42 filled in the coolant container 43 and then the hermetically sealed container 44 therethrough. The temperature in the hermetically sealed container 44 drops from the periphery thereof to the center of the filters 49a, 49b and 49c. Made of a material having a good thermal conductivity, the filters 49a, 49b and 49c cool rapidly, thus permitting gas cleaning to be started in a shorter time.
When the temperature sensor 52 senses that the secondary coolant 42 has been cooled to a temperature slightly below the freezing point thereof, the primary coolant supply unit stops the supply of the primary coolant and a gas to be cleaned flows in through the supply pipe 45. The gas passes through the filters to the discharge pipe 46. During this travel, the secondary coolant 42 liquefies and adsorbs gases (vapors) of impurities that evaporate at higher temperatures than the secondary coolant 42. After the gases of impurities, moisture and dust have been removed by the filters 49a, 49b and 49c, a cleaned gas flows outside through the discharge pipe 46.
Though heated by the supplied gas, the secondary coolant 42 cooled to a temperature slightly below the freezing point thereof can maintain a constant temperature for a relatively long time because of the latent heat of melting. This permits increasing the intervals at which the secondary coolant 42 is cooled by the primary coolant and, therefore, facilitates the temperature control thereof.
In all of the preferred embodiments described herein, the coolant is released into the atmosphere. But the coolant may also be collected and liquefied in a container for recirculation. | A gas cleaner dehumidifies a chamber or other container, into which air or other gases are supplied, in order to realize the minimizing of the moisture held therein, which is an indispensable requisite to quick evacuation. A hermetically sealed container of a thermally conductive material is immersed in a coolant filled in a coolant container. Filters of a thermally conductive sintered metal disposed in the hermetically sealed container cools and liquefies the gas admitted through a supply pipe and thereby removes the unwanted moisture. | 1 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to surgical instrument for fixing, preferably in a minimally invasive arthroscopic manner, a cartilaginoid tissue to an underlying bone, with particular reference to an acetabular lip accidentally detached from the osseous edge or rim of a femoral acetabulum.
[0002] As is known, the fixing of an acetabular lip which, for several reasons, has been detached from an underlying bone, is at present carried out by suture anchoring elements, similar to those used in shoulder surgical operations, which frequently require a very invasive so-called “open sky” intervention.
[0003] In particular, for applying the above mentioned suture anchoring elements, it is necessary to properly prepare the hip bone, by forming at least a pre-hole and engaging in said pre-hole a dedicated fixation or clamping device.
[0004] Then, to the head of the above device one or more suture threads, for fixing the cartilaginoid tissue, for example, to the articular lip, are connected.
[0005] For each anchoring element, it is necessary to repeat the just disclosed operations, which greatly extends the surgical operation time.
[0006] Moreover, it is very difficult to perform, by the above method, an arthroscopic type of operation and, accordingly, the fixing operation must be carried out by using a substantially conventional type of surgical instrument or tool, with the risk of greatly damaging the underlying bone parts.
SUMMARY OF THE INVENTION
[0007] Accordingly, the main aim of the present invention is to overcome the above mentioned drawbacks of prior fixing methods, by providing a novel fixing surgical instrument, specifically designed to perform a minimally invasive fixing operation, in particular an arthroscopic fixing operation.
[0008] Another object of the present invention is to greatly reduce the surgical operation time, while providing a novel surgical fixing or fixation instrument, adapted to perform a much more simple and quick surgical fixing operation.
[0009] Another object of the present invention is to provide such a novel surgical instrument providing a safe reliable fixing of the cartilaginoid tissue, and which is construction wise very simple and reliable, and which, moreover, allows to perform a consistently repeatable fixing intervention.
[0010] Another object of the present invention is to provide such a minimally invasive quickly operating surgical instrument allowing fixing operations to be performed arthroscopically, thereby greatly reducing possible risks related to the surgical operation, such as an infective, anaesthesia and blood loss risks.
[0011] Another object of the present invention is to provide such a surgical instrument capable of fixing the cartilaginoid tissue to the bone without drilling pre-holes or grooves in the bone.
[0012] Another object of the present invention is to provide such a surgical instrument allowing to fix the cartilaginoid lip without the need of performing fixing manual operations to clamp, by suture threads, the cartilaginoid tissue to the underlying bone.
[0013] Yet another object of the present invention is to provide such a surgical instrument which can be easily used in any operating rooms, requires a minimum maintenance and, moreover, is very competitive from a mere economic standpoint.
[0014] According to one aspect of the present invention, the above mentioned objects, as well as yet other objects, which will become more apparent hereinafter, are achieved by a surgical instrument for fixing, preferably in a minimally invasive arthroscopic manner, a cartilaginoid tissue to an acetabular lip accidentally detached from a. bone rim of a femoral acetabulum, characterized in that said instrument comprises a proximal beating mass, having a portion removably engageable with the proximal end of a middle portion having a distal end thereof adapted to support a replaceable fixing device which can be removably coupled to said distal end of said middle part, and a cannula part adapted to slidably receive therein said middle part with said fixing device removably coupled thereto.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Further characteristics and advantages of the surgical instrument according to the present invention will become more apparent hereinafter from the following detailed disclosure of a preferred, though not exclusive, embodiment thereof, which is illustrated, by way of an indicative, but not limitative example, in the accompanying drawings, where:
[0016] FIG. 1 is an exploded perspective view, showing the main component parts of the surgical instrument or tool according to the present invention;
[0017] FIG. 2 is a partial perspective view showing possible geometrical configurations of respective fixing elements which can be applied by the surgical instrument shown in FIG. 1 ;
[0018] FIG. 3 is a detail perspective view showing a possible configuration or embodiment of a cartridge and/or block supporting element, specifically designed for slidably supporting thereon the fixing element or device shown in FIG. 2 ;
[0019] FIGS. 4A (from a to c) and 4 B (from a′ to c′) show further partial perspective view of parts of the surgical instrument according to the present invention, useful for understanding the operation of this instrument;
[0020] FIG. 5 is a further detail view, as partially cross-sectioned, showing a detail of the surgical instrument according to the present invention, with the fixing device already engaged in its cartridge and cannula and ready for fixing an acetabular lip to an underlying bone (herein not shown);
[0021] FIG. 6 is yet another perspective view illustrating an upper or top detachment of the acetabular lip;
[0022] FIG. 7 is yet another perspective view showing the surgical instrument according to the present invention in a ready condition to perform a fixing operation of the acetabular lip; and
[0023] FIG. 8 is yet another perspective view showing an operating mode of the surgical instrument according to the present invention, after having fixed the acetabular lip to the underlying bone, by applying a single fixing or clamping element or device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] With reference to above mentioned figures, in FIG. 1 the surgical instrument or tool according to the present invention, has been generally indicated by the reference letter S.
[0025] Said instrument comprises a beating mass, generally indicated by the reference number 2 , a middle part, generally indicated by the reference number 3 , a fixing device bearing carriage, generally indicated by the reference number 4 , and a cannula, generally indicated by the reference number 5 .
[0026] The beating mass 2 of the surgical instrument S comprises, in turn, a substantially solid cylindric beating or impacting head 6 , integral with a central stem, also of a substantially solid cylindric configuration, 7 , having a diameter less than that of the beating or impacting head 6 .
[0027] The middle part 3 of the surgical instrument S defines a substantially cylindric hollow proximal end portion 8 , having at least a guide slotted longitudinal opening 9 , for removably slidingly engaging therein the central stem 7 of the beating mass 2 .
[0028] Said cylindric hollow portion 8 has an end face 10 , operating as a closure bottom for the cylindric portion 8 and therefrom integrally extends a rod-like element, of substantially cylindric configuration 11 , having a diameter much smaller than that of the cylindric hollow portion 8 , and ending with a substantially flat distal end portion, generally indicated by the reference number 13 .
[0029] The cannula part 5 , in turn, comprises a substantially cylindric hollow head portion 14 , designed for abutting, with the rod 11 being engaged in the cannula, against the face 10 of the cylindric hollow portion 8 of the middle part 3 , and a cylindric thin cannula portion 15 , extending substantially centrally and integrally from the head portion 14 of the cannula 5 , and having a diameter substantially less than that of said head portion 14 . The carriage element 4 , which is shown in a more detailed manner in the perspective view of FIG. 4 ( b ) and in the top plan view in FIG. 4B (c′), comprises, in turn, an elongated cylindric or plug body 16 having a substantially longitudinal central slot 17 , for engaging therein a cartridge and/or block element, generally indicated by the reference number 18 in FIG. 3 , having a block body 19 in which is formed a longitudinal slot 20 in which is slidably engaged a fixing device, generally indicated by the reference numbers 21 and 22 in FIG. 2 , respectively.
[0030] More specifically, according to a first embodiment thereof, the fixing device 21 comprises a substantially L-shape hook element, having a short arm 23 and a long arm 24 .
[0031] Advantageously, the long arm 24 ends with a sharpened pointed portion 25 .
[0032] Said fixing devices 21 and 22 may have different lengths, sizes and cross sections, to perfectly fir specific requirements of the patient, in particular, for properly resisting against any withdrawal and twisting forces applied to the fixing device.
[0033] More specifically, the fixing device 21 has a substantially circular cross-sections, whereas the fixing device 22 comprises a clip element 26 , of substantially U-shape, and having two respective end spaced tip portions 27 and 28 , said clip element 26 further advantageously including surface teeth for improving its anchoring to the bone, after having applied by impacts said clip element 26 to the bone, through the surgical instrument S, as it will become more apparent hereinafter.
[0034] According to an important aspect of the present invention, the fixing device, which has substantially a L-hook, or a U-clip shape, comprises moreover, in addition to one or two sharpened tips, a surface textured portion, to prevent it from being accidentally withdrawn from the bone under accidental stresses.
[0035] Advantageously, the clamping device 21 or 22 is made of a biocompatible material, adapted to prevent or minimize possible troubles due, for example, to possible clinical analyses, such as NMR analyses, necessary to evaluate a good fixation of the cartilaginoid tissue to the bone and, accordingly, the recovery course of the patient.
[0036] Thus, the above mentioned biocompatible material must be of non magnetic nature, and capable to minimize any possible artefacts.
[0037] By way of an example, the fixing device can be made of titanium and alloys thereof, biocompatible polymers or other metals or metal alloys, either of a shape memory or of a standard type, provided that they have the above mentioned features.
[0038] Thus, the fixing devices 21 or 22 , respectively the hook element, or U-shape element, can be engaged in the bone, as it will become more apparent hereinafter, without the need of preliminarily drilling a hole or a recess in said bone, thereby advantageously reducing the operating time and, accordingly, any risks of the surgical intervention (such as infections, anaesthesia or hematic losses).
[0039] In FIG. 3 , the fixing device 21 has been shown as slidably supported in said support cartridge 18 , which cartridge is advantageously of a disposable type and, in addition to operate for containing the fixing device therein, can be removably slidably engaged in said slot 17 of the body 16 of the carriage 4 , to allow the device to be easily handled and engaged by the instrument S.
[0040] Actually, as stated, said cartridge and/or block 18 comprises a longitudinal slot 20 restraining therein the fixing device ( 23 in FIG. 3 ) and properly guiding said device as it is impacted into the bone, as it will become more apparent hereinafter.
[0041] With reference now to FIGS. 4A to 4B , the fixing device supporting carriage 4 can be engaged/assembled in/to the middle part 3 , and, in particular, in/to its flat tip portion 13 , through the longitudinal slot 17 of the carriage 4 .
[0042] This coupling to, and a corresponding disengaging from said middle part 3 , can be performed in a very easy manner, for example by a snap type of operation.
[0043] Actually, the carriage 4 can be easily disassembled or detached by removing the fixing device supporting cartridge 18 from its seat ( FIG. 4A , c) ( FIG. 4B , a′), thereby allowing the surgical instrument, and in particular, the middle part 3 thereof, to be easily cleaned and sterilized.
[0044] On the contrary, with the cartridge 18 arranged in its seat ( FIG. 4B , b′), said carriage cannot be detached or disassembled, thereby allowing said fixing devices 21 and/or 22 , which have a very small size, to be easily handled or driven, thereby preventing them from being accidentally disengaged ( FIG. 4B , c′). Finally, as is shown in FIG. 4B , c′, the carriage 4 also comprises a hole F for allowing the cartridge 18 to be easily removed, as necessary, and suitable machined regions, such as locking ribs F′, F″, for preventing the cartridge from being ejected in a longitudinal direction.
[0045] In this connection it should be pointed out that the cartridge 18 for supporting the fixing device 21 and/or 22 will be pre-assembled with the fixing device itself, thereby causing its tip portion 25 , or 27 and/or 28 , to project from the instrument S in an assembled condition of the latter. Thus, it is possible to easily grip the cartilaginoid tissue and fix this tissue at any desired positions, without using other tools or operators, at it is clearly shown in FIG. 5 .
[0046] Thus, the cartridge 18 and inner portion of the surgical instrument S will prevent the device being impacted upon from deviating from a desired operating path. Actually, the instrument S is operatively impacted by causing the beating mass 2 , made integral with the inner part 3 , to slide in the guide groove and/or elongated slot 9 of the inner part of the instrument S.
[0047] Accordingly, as it will become apparent to one skilled in the art, the inventive surgical instrument S allows to implant any desired number of fixing devices 22 and/or 23 , without removing said cannula 15 , and this by merely withdrawing or removing the inner part 3 and the carriage 4 from the cannula 15 , while also removing the empty cartridge 18 (which operation can be easily performed due to the provision of said hole F of the carriage 4 ), and by engaging a fresh cartridge and related fixing device 21 and/or 22 .
[0048] FIG. 5 is a partial cross-section view illustrating the fixing device 21 supported in its supporting cartridge. 18 , and engaged in the respective cannula 15 .
[0049] FIG. 6 shows a schematic view of the acetabular lip LA, having an upper or top detached portion DS.
[0050] In particular, the cotyloid fossa FC, the articular hyalinic cartilage CIA, and the acetabular transverse ligament LT are herein shown.
[0051] FIG. 7 is a schematic view provided for clearly understanding the operation of the inventive surgical instrument S.
[0052] In particular, in FIG. 7 , the instrument tp 25 is shown arranged in the cannula, after having engaged the middle part of the instrument S, near the lip L to be fixed.
[0053] As shown in FIG. 8 , by applying suitable repeated impacts to the head 6 of the beating mass 2 in the direction of the arrow A, for example by a mallet manually driven by the surgeon (not shown), the tip or point portion 5 will be caused to enter both the acetabular lip LA and the underlying bone, thereby completing the fixing operation, by causing the fixing device 21 to be deeply engaged in the bone.
[0054] In this connection it should be apparent that this operation can be easily and quickly repeated to provide a perfect fixation by further fixing hook elements 21 to be applied at any desired position, as chosen by the surgeon.
[0055] Thus, it is apparent that the inventive surgical instrument S allows to implant any desired number of fixing devices 21 and/or 22 , without removing the implanted cannula, but merely withdrawing the inner part 3 and the carriage 4 from the cannula, while removing the empty cartridge 18 (which operation can be easily performed owing to the provision of the carriage hole F), and by introducing a fresh cartridge and related fixing device 21 and/or 22 .
[0056] From the above disclosure it should be apparent that the invention fully achieves the intended aim and objects.
[0057] While the invention has been disclosed with reference to preferred embodiments, it should be apparent that the disclosed embodiments are susceptible to several modifications and variations, all of which will come within the scope of the invention.
[0058] In practicing the invention, the used contingent materials and/or sizes and/or shapes can be any, depending on requirements. | A surgical instrument ( 5 ) for fixing, preferably in a minimally invasive arthroscopic manner, a cartilaginoid tissue to an underlying bone, in particular to an acetabular lip, accidentally detached from the bone edge of a femoral acetabulum is characterized in that said instrument comprises a proximal beating mass ( 2 ), which can be removably engaged with a proximal end ( 8 ) of a middle part ( 3 ) having the distal end ( 13 ) thereof designed for supporting a replaceable fixing device ( 21,22 ) which can be removably coupled to said distal end of said middle part, and a cannula part ( 5 ) designed for slidably receiving therein said middle part with said fixing device removably coupled thereto. | 0 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
BACKGROUND OF THE INVENTION
[0002] The present invention relates to the use of human embryonic stem cells to create blood-related cells, and the use of those blood-related cells for various purposes.
[0003] Techniques for isolating stable cultures of human embryonic stem cells have recently been described by our laboratory. See U.S. Pat. No. 5,843,780 and J. Thomson et al., 282 Science 1145-1147 (1998). The disclosure of these publications and of all other publications referred to herein are incorporated by reference as if fully set forth below.
[0004] We have deposited two of our human embryonic stem cell lines with the American Type Culture Collection, 10801 University Boulevard, Manassas, Va. 20110-2209 U.S.A. on Jul. 7, 1999 and Jul. 15, 1999 respectively (with accession numbers PTA-313 and PTA-353 respectively). These deposits are under the conditions of the Budapest Treaty. Taxonomic descriptions of these deposits are human embryonic stem cell lines H1 and H9 respectively. It has been proposed in these publications that such cell lines may be used for, among other things, providing a source of specified cell lines of various types for research, transplantation and other purposes.
[0005] Under the storage and culturing conditions described in these publications the cell lines are maintained long term without differentiation into specific cell types. When the cell lines are subsequently injected into immunodeficient mice, they form teratomas demonstrating differentiation into multiple tissue types.
[0006] When ES cells are used to produce desired cells, it is often preferable to optimize differentiation towards specific cell types. In the case of hematopoietic cells it is desirable that this result in hematopoietic cells that can be isolated and used to form multiple hematopoietic lineages. These cells may include, but not be limited to, hematopoietic stem cells.
[0007] Hematopoietic stem cell populations have been isolated directly from bone marrow. See C. Baum et al. 89 PNAS U.S.A. 2804-2808 (1992). However, this relies on a supply of bone marrow to obtain the cells.
[0008] There have also been some attempts to direct murine embryonic cell populations towards hematopoietic cells. See e.g. U.S. Pat. No. 5,914,268; G. Keller, 7 Current Opinion In Cell Biology, 862-869 (1995); and T. Nakano et al. 265 Science 1098-1101 (1994). See also M. Weiss, 11 Aplastic Anemia And Stem Cell Biology, 1185-1195 (1997); and S. Morrison et al., 11 Annu. Rev. Cell Dev. Biol., 35-71 (1995).
[0009] However, applying these teachings to primates has proven difficult. For example, in F. Li et al., 92 Blood 368 a (1998) there was a discussion of techniques for differentiation of rhesus embryonic stem cell lines using a stromal cell line and exogenous cytokines. However, that group has more recently reported that their techniques had inadequate formation of colonies.
[0010] The treatment of various diseases by tissue transplantation has become routine. However, there can be waiting lists to obtain natural donated organs, cells, or tissue. Even when the natural donor material becomes available there is often a problem with rejection. Traditional approaches for suppressing an immune response of recipients have drawbacks. For example, immunosuppressive drugs are costly and often have side effects.
[0011] In WO 98/07841 there was discussed techniques of deriving embryonic stem cells that are MHC compatible with a selected donor (e.g. transplanting a donor nucleus into an enucleated oocyte, followed by derivation of the stem cells therefrom). The application suggested that the resulting cells could be used to obtain MHC compatible hematopoietic stem cells for use in medical treatments requiring bone marrow transplantation.
[0012] However, some diseases such as type 1 diabetes mellitus or multiple sclerosis involve an autoimmune response. For example, merely transplanting pancreatic islets (which are MHC compatible to the diseased individual) to replace destroyed pancreatic islets will not provide sufficient long term reduction in type 1 diabetes mellitus, as the immune system of the host will still attack the transplanted islets.
[0013] It can therefore be seen that a need exists for techniques for causing human embryonic stem cell cultures to differentiate to desired hematopoietic colonies. Further, it is desired to develop improved uses for hematopoietic cells.
BRIEF SUMMARY OF THE INVENTION
[0014] In one aspect the present invention provides a method for obtaining human hematopoietic cells. One exposes a human embryonic stem cell culture to mammalian hematopoietic stromal cells so as to thereby create human hematopoietic cells. At least some of the human hematopoietic cells that are so created are CD34 + and/or are capable of forming hematopoietic cell colony forming units in methylcellulose culture.
[0015] CD34 is a standard marker for hematopoietic stem cells, as described in C. Baum et al. 89 PNAS U.S.A. 2804-2808 (1992) and S. Morrison et al., 11 Annu. Rev. Cell Dev. Biol., 35-71 (1995). The property of capability of forming a colony forming unit is indicative that the cells have the desired characteristics to form more differentiated hematopoietic lineages.
[0016] The stromal cells are preferably derived from bone marrow cells or embryonic yolk sac cells. Murine stromal cells may be used for this purpose. However, primate stromal and other mammalian stromal cells should be suitable as well.
[0017] In another aspect the invention provides a human hematopoietic cell which was derived from a human embryonic stem cell culture in vitro, and is capable of forming hematopoietic cell colony forming units in methylcellulose culture. As used in this patent, the term “derived” is intended to mean obtained directly or indirectly (e.g. through one or more intermediates or passages).
[0018] In yet another aspect the invention provides a method of transplanting human cellular material into a human recipient host. One obtains human hematopoietic -cells which have been derived in vitro from an embryonic stem cell culture. One then obtains a selected human cellular material other than hematopoietic cells, the selected non-hematopoietic material having major histocompatibility complex compatibility to the hematopoietic cells. One then transplants both the hematopoietic-cells and selected human non-hematopoietic cellular material into the human host.
[0019] For example, one can obtain human hematopoietic cells which have been derived in vitro from an embryonic stem cell culture (e.g. using the techniques described below). One also obtains human pancreatic islets which have MHC compatibility to the hematopoietic cells. Both the hematopoietic cells and pancreatic islets are then transplanted into the human (preferably after the recipient's own bone marrow has been inactivated).
[0020] The pancreatic islets can be obtained directly from a donor whose cells were used to create the embryonic stem cell culture. Alternatively, a single embryonic stem cell culture can be differentiated along two different paths. In one process the above technique can be used to create hematopoietic stem cells. These cells should develop into multiple hematopoietic lineages when transplanted into appropriate hosts. These lineages should include lymphocytes which would be tolerant of other cells derived from the same parental embryonic stem cells. In another process the stem cells would be directed towards pancreatic islets.
[0021] In another example one could supply oligodendrocytes to a human who has a multiple sclerosis condition. One obtains human hematopoietic cells which have been derived in vitro from an embryonic stem cell culture (e.g. using a technique described below). One also obtains human oligodendrocytes which have MHC compatibility to the bone marrow cells and transplants both the bone marrow cells and oligodendrocytes into the human.
[0022] The same human whose genetic material was used to create the embryonic stem cell can be a donor for the oligodendrocytes. Alternatively, the same embryonic stem cell culture can be differentiated along two separate paths to provide the two transplantable materials.
[0023] With respect to either disease (and potentially other autoimmune diseases) the immune-and auto-immune rejection problems should be reduced by this technique. In this regard, the recipient's original bone marrow can be totally or partially inactivated by radiation or chemical means before the transplantation. Thereafter, it is replaced at least in part by the transplanted hematopoietic cells. The elimination/reduction of the original bone marrow reduces the body's ability to create an autoimmune response. The matching of the MHC of the replacement bone marrow and the second transplantable material insures that the second material won't be rejected by the transplanted bone marrow.
[0024] Moreover, co-transplantation of hematopoietic cells and other tissue can be done to promote acceptance of the second tissue (e.g. heart muscle plus hematopoietic cells for treating heart disease; hepatocytes plus hematopoietic cells for treating liver disease). By creating hematopoietic chimeras improved acceptance of tissues with similarly matched MHC type can be obtained.
[0025] The present invention should be suitable to obtain a wide variety of hematopoietic cells of interest, such as erythroid cells, granulocyte cells, macrophages, lymphocyte precursors, monocytes, B cells, T cells, and the like. In this regard, colonies of differentiated ES cells develop into hematopoietic colonies when harvested, separated into single cells, and plated into appropriate cultures. These colonies demonstrate the development of colony-forming cells which proliferate into colony-forming units (including colony forming unit-erythroid (CFU-E), blast forming unit-eythroid (BFU-E), colony forming unit-macrophage (CFU-M), colony forming unit-granulocyte/macrophage (CFU-GM) and colony forming unithigh proliferative potential (CFU-HPP)). The identification of colony forming cells indicates the differentiation of embryonic stem cells into hematopoietic cells capable of expanding into defined hematopoietic lineages under defined conditions.
[0026] The objects of the present invention therefore include providing:
[0027] (a) methods of the above kind for obtaining hematopoietic cells;
[0028] (b) cells derived using those methods; and
[0029] (c) methods for using those derived cells for transplantation, transfusion and other purposes. These and still other objects and advantages of the present invention will be apparent from the description of the preferred embodiments that follows. However, the claims should be looked to in order to judge the full scope of the invention.
DETAILED DESCRIPTION
Embryonic Stem Cell Culture
[0030] The previously described human ES cell line Hi was used for the majority of experiments, albeit some of the following studies were done with the previously described ES cell lines H9 (or H9.2) with similar results. These cells were removed from frozen (liquid nitrogen) stocks of cells derived from the original isolated and propagated cell line. The Hi ES cells were grown in 6 well culture dishes (Nunclon, Fisher).
[0031] The dish was first coated with 0.1% gelatin solution (Sigma) for one or more days in a 37° C./5% CO 2 incubator. After the one or more days, the gelatin solution was removed and the wells of the plate were next coated with irradiated mouse embryonic fibroblast (MEF) cells. MEF cells were derived from day 12-13 mouse embryos in medium consisting of DMEM (GibcoBRL) supplemented with 10% fetal bovine serum (Hyclone or Harlan), 2 mM 1-glutamine (GibcoBRL), and 100 units/ml. Penicillin, 100 mg/ml streptomycin (Sigma).
[0032] The MEF cells were irradiated with 5500 cGy from a cesium source prior to plating in the wells. The MEFs were added at a density of 5×10 4 cells/ml, 2.5 ml/well. The plate coated with MEFs was then placed in 37° C./5% CO 2 incubator for one or more days until addition of ES cells.
[0033] ES cells were passed onto new MEFs at approximately 5-8 day intervals. The time depends on cell density and morphologic appearance of differentiation. For passage, the medium in a well of ES cells was removed and 1-2 ml of medium containing 1 mg/ml collagenase IV in DMEM (GibcoBRL) was added. The plate was then placed at 37° C./5% CO 2 for 5-20 minutes until the colonies of ES cells began to round up.
[0034] The well was then scraped with a 5 ml pipette to detach the ES cells from the plate. The contents of the harvested well were placed in a 15 ml conical tube (Fisher) and spun in a centrifuge at 1000 rpm for 5 minutes. The medium was removed and 10 ml of fresh medium was added. This ES cell medium consists of F12/DMEM (GibcoBRL)) supplemented with 20% serum replacement medium (GibcoBRL), 8 ng/ml of bFGF (GibcoBRL), 1% nonessential amino acid solution (GibcoBRL), 1 mM 1 glutamine (GibcoBRL), and 0.1M β-mercaptoethanol.
[0035] The cells were again spun (5 min/1000 rpm), medium removed and resuspended at a concentration of 2.5 ml of medium for each (typically 15 ml medium for plating into 6 new wells, this would be a 1:6 passage). The cells were then pipetted into the wells of a plate that had been previously coated with MEFs as described above. The cells were evenly distributed into each well and the plate was placed in an incubator at 37° C./5% CO 2 .
[0036] At times if there were colonies of ES cells showing morphologic appearance of differentiation prior to cell passage, these colonies were removed by gentle scraping with a pulled glass pipette. This was done with observation through a dissecting microscope. After removal of the differentiated cells, the remaining colonies were passaged as above.
[0037] After passage, each well of ES cells was “fed” with fresh medium at 24-48 hour intervals. Here, the medium of each well was removed and 2.5 ml of fresh ES medium was added. All feeding and passage of ES cells were done in a sterile environment.
Differentiation of ES Cells
[0038] To promote hematopoietic differentiation of the human ES cells, the ES cells were harvested as above. The cells were then plated in 6 well plates coated with a mammalian stromal cell. In one experiment we used C166 cells that were previously irradiated with 2500 cGy. The C166 cells were originally obtained from the yolk sac of mice at embryonic day 12 and were graciously provided by Dr. Robert Auerbach (UW-Madison).
[0039] In another experiment, S17 cells were used. They were originally obtained from mouse bone marrow, and were graciously provided by Dr. Kenneth Dorshkind (then at UCRiverside, now at UCLA).
[0040] The C166 or S17 cells were plated at a density of 1×10 5 cells/ml, 2.5 ml/well. The ES cells plated onto either S17 of C166 cells were then allowed to grow in a medium consisting of DMEM (GibcoBRL) supplemented with 20% fetal bovine serum (Hyclone), 1% nonessential amino acid solution, 0.1 M β-mercaptoethanol, and 1 mM 1 glutamine. This medium was replaced in each well at 24-72 hour intervals with fresh medium. In selecting an appropriate medium, one merely needs to provide conventional conditions for cell growth, albeit supplemented with the specified stromal cells.
[0041] After 3-7 days from plating onto S17 or C166 cells, the ES cells began to visually appear differentiated in that they did not have the same uniform appearance as the undifferentiated ES cells maintained on MEF feeder cells. The colonies of ES cells began to form multiple different cell types. Some of these colonies had regions that appeared to consist of cells with a cobblestone morphology indicative of colonies of early hematopoietic progenitor cells.
Confirming Blood-Related Cells
[0042] One method to determine the presence of appropriate hematopoietic cells is to assay for hematopoietic colony forming cells (CFCs) in semisolid methylcellulose containing medium. Here, the ES cells were allowed to differentiate on either C166 or S17 cells for 2-3 weeks, maintained as described above. After this time the medium was removed. 2.5 ml of calcium and magnesium free phosphate buffered saline (PBS) was added for 2-5 minutes, removed, and 1.5 ml. of trypsin (0.125%)-EDTA (1mM) medium was added.
[0043] The cells were then placed at 37° C./5% CO 2 for 10 minutes. After this time, the colonies began to disassociate. The cells were further disassociated by pipetting and scraping the wells. The cells were placed in a 15 ml. conical, spun 5 min/1000 rpm, medium removed and 10 ml fresh medium (DMEM+10% FBS+1-glutamine+pen/strep) was added, and spun again. The cells were then suspended in 5 ml medium and passaged through a 100 mM nytex filter to remove clumps of cells.
[0044] The filter was washed with an additional 5 ml medium. The disassociated/filtered cells were then counted on a hemacytometer and 1×10 6 (usually, but not always this many cells) cells were placed in a new 15 ml conical. These cells were then spun, medium removed and 5 ml medium consisting of IMDM (GibcoBRL) supplemented with 2% fetal bovine serum (Hyclone) was added. Cells were spun, medium removed and 250 ul medium (IMDM+2% FBS) was added.
[0045] In accordance with the specified test conditions, these cells were then added to 2.5 ml of Methocult GF+ H4435 medium (StemCell Technologies). This medium consists of 1.0% methylcellulose, supplemented with 30% FBS, 20 ng/ml IL-3, 20 ng/ml IL-6, 50 ng/ml stem cell factor, 3 units/ml erythropoietin, 20 ng/ml GM-CSF, 20 ng/ml G-CSF, 2 mM 1-glutamine, 0.1 mM b-mercaptoethanol, 1% bovine serum albumin. The cells in methylcellulose were then vortexed vigorously and then 1.1 ml of the mixture was plated onto a P35 plastic dish (Stem Cell Technologies), spread evenly on the dish and placed at 37° C./5% CO 2 .
[0046] Duplicate plates of each sample were typically plated with 4×10 5 cells/plate. After 14-21 days, the plates were analyzed under a microscope for the presence of hematopoietic colonies. The colonies were identified by comparison to a colony atlas (StemCell Technologies) or the book: Culture of Hematopoietic Cells, RI Freshney, IB Pragnell, MG Freshney, eds., Wiley-Liss, Inc. 1994. Colonies were identified as one of the following: colony forming unit-erythroid (CFU-E), blast forming uniteythroid (BFU-E), colony forming unit-macrophage (CFU-M), colony forming unit-granulocyte/macrophage (CFU-GM) or colony forming unit-high proliferative potential (CFUHPP).
[0047] The presence of the desired hematopoietic cells can also be confirmed by flow cytometry. One can look for specified cell surface antigens by flow cytometry. Here, ES cells differentiated on S17 cells or C166 cells as described above for 14-21 days, were harvested with trypsin/EDTA as described above and passed through a 100 mM nytex filter. The filtered cells were counted on a hemacytometer, then aliquotted into 15×75 plastic tubes (Fisher) at approximately 1×10 5 cells/tube. The cells were then spun, medium removed and 2-3 ml of FACS medium was added. (FACS medium is PBS with 0.5% BSA (Sigma), 0.1% sodium azide (Sigma)).
[0048] The cells were again spun and medium removed. Next an antibody directly linked to a fluorescent marker (FITC or PE) was added to the wells at a concentration as recommended by the supplier. Cells have been analyzed with the following antibodies: CD34-FITC (Immunotech), CD45-PE (Pharmingen). IgG1-FITC and IgG1-PE were used as isotype controls for non-specific staining of the cells. Cells were incubated with the appropriate antibody for approximately 30 min on ice, washed 1-2 times with 2-3 ml FACS medium and resuspended in approximately 0.5 ml FACS medium.
[0049] The antibody labeled cells were then analyzed using a FACScan (Becton Dickinson) as per manufacturers recommendations. The presence of dead cells was determined by addition of propidium iodide (1 mg/ml solution, 5 ul added per tube) or 7-AAD (Calbiochem) (0.2 mg/ml ,5 ul/tube). The software for analysis was either PC Lysis or Cellquest.
[0050] The following experimental techniques were used to analyze antigen expression by immunohistochemistry (IHC). Here, differentiated ES cells that have been co-cultured with either C166 or S17 as above, were harvested with trypsin/EDTA as above. The cells were resuspended in medium containing DMEM supplemented with 10% FBS at a concentration of approximately 1×10 4 -1×10 5 . “Cytospin” preparations of these cells were then made by spinning 1×10 3 -1×10 4 cells onto a glass slide (Superfrost/plus, Fisher) with a Cytospin II centrifuge (Shanndon).
[0051] These slides were then fixed with cold acetone and stored frozen at −20° C. For IHC staining the slides were thawed at room temperature and the cell pellet was outlined with a wax pen (DAKO). The cells were then stained as follows using a Vectastain ABC kit (Vector Laboratories, Burlingame, CA), all incubations were at room temperature. 100-200 ul PBS was added onto the cells for 5 minutes then removed. Vectastain blocking antibody solution (horse serum) was then added onto the cells for 15 minutes. The cells were then blotted dry and 100-200 ul of primary antibody solution was added. The primary antibodies were: IgG1 (1 ug/sample, Sigma), anti-CD34 (0.5 ug/sample, Immunotech), anti-CD45 (1 ug/sample, DAKO), anti-class I (1 ug/sample, gift from Dr. Paul Leibson, Mayo Clinic), anti-CD14 (1 ug/sample, Pharmingen), anti-CD31 (1 ug/sample, Pharmingen).
[0052] Primary antibody was added for 30 minutes followed by PBS for 10 minutes. Next, biotinylated anti-IgG antibody was added (Vectastain kit, solution B) for 30 minutes followed by PBS for 10 minutes. Next Vectastain ABC solution was added for 30 minutes at room temperature followed by PBS for 10 minutes. Next DAB solution (Vectastain) was added for 5 minutes followed by washing under running tap water for 10 minutes. In some experiments, the slides were then counterstained with Gill's hematoxylline solution (Vector labs) for 3 minutes followed by washing with running tap water for 10 minutes. The slides were then air dried. Cells staining positive appear brown.
[0053] CD34 + was demonstrated within a mixed population of cells (about 1%) after 2-3 weeks. Even more importantly, differentiated ES cells were shown to develop into hematopoietic colonies when harvested, separated into cells and plated into methylcellulose (semi-solid) cultures.
Transplantation
[0054] Currently hematopoietic cell transplantation is conducted clinically primarily for patients who have received high dose chemotherapy for treatment of malignancies. These patients typically receive a heterogeneous mixture of hematopoietic cells either from an autologous or allogeneic source. Human ES-derived hematopoietic stem cells will at minimum provide a more homogeneous cell population for hematopoietic cell transplantation.
[0055] Further, as discussed above, the MHC characteristics of the transplantation can now be controlled, thereby enabling treatment of autoimmune diseases. For example, both hematopoietic stem cells (HSCs) and a second lineage (e.g. pancreatic islets for diabetes or oligodendrocytes for multiple sclerosis) could be derived from the same parental ES cell line. With both lineages available, a hematopoietic chimera could be first created by performing a fully allogeneic hematopoietic cell transplant (HCT). The established state of chimerism would allow the recipient's immune system to “see” the subsequent transplant of the second cell type (e.g. pancreatic islets cell or oligodendrocyte) as “self” and should not be rejected.
[0056] Note for example that oligodendrocytes have been obtained from mouse ES cells (0. Brustle et al., 285 Science 754-6 (1999)), as have cardiac muscle cells (M. Klug et al., 98 J. Clin. Invest. 216-224 (1996)).
[0057] This method of creating hematopoietic chimeras will also promote acceptance of tissues transplanted for reasons other than autoimmunity. In this regard, mice receiving allogeneic hematopoietic stem cells do not reject other tissues with the same genetic background as the hematopoietic cells, but will still reject thirdparty grafts. See K. Gandy et al., 65 Transplantation 295-304 (1998).
[0058] In addition to animal studies, there are now clinical case reports of human patients who have previously received a hematopoietic cell transplant later requiring a solid organ (kidney) transplant. In these instances, the kidney transplant from the same person who had previously supplied the bone marrow transplant is immunologically accepted without further immunosuppression. See T. Spitzer et al., 68 Transplantation 480-484 (1999).
[0059] Work in canine models and more recently in human clinical trials has shown that milder non-myeloablative conditioning regimens can be used to better prepare hosts for allogenic HCT. Here, only moderate doses of total body irradiation and a short course of immunosuppression are used to prepare the hosts prior to receiving allogeneic HCTs.
[0060] Even though the preferred embodiments have been described above, it will be appreciated by those skilled in the art that other modifications can be made within the scope of the invention. For example, while two specific stromal type cells have been selected for use, many others are also suitable. For example, one publicly available stromal cell line is the M2-10B4 cell line having ATCC designation number CRL-1972.
[0061] Further, while the above description focuses on the creation of precursors for red blood cells and bone marrow, various other blood-related cells of interest can be obtained in quantity using the above techniques. See also U.S. Pat. No. 5,914,268. Thus, the claims should be looked to in order to judge the full scope of the invention.
Industrial Applicability
[0062] The invention provides blood-related cells useful for transplantation, research and other purposes. | Disclosed herein are methods of obtaining human hematopoietic cells from human embryonic stem cells using mammalian stromal cells. Hematopoietic cells derived in this way are useful for creating cell cultures suitable for transplantation, transfusion, and other purposes. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a washing machine of a type which can automatically correct abnormal conditions which may sometimes occur.
As is well known in the art, in a washing machine the rotary blades of the agitator or pulsator are turned by an electric motor to wash clothes placed in a washing tub of the machine. The motor is usually coupled to the agitator or pulsator through an endless belt.
Sometimes the motor may be forcibly stopped by a external cause, for instance, when an excessively large load is put in the washing machine, or when foreign matter is caught between the tub and the rotary blades, or when a bearing seizes.
If a motor is maintained locked for a long period, it may burn out due to over-heating. This difficulty has heretofore been eliminated by employing a heat-sensitive fuse or a self-restoring type protective unit built into the motor so that, if the motor starts to over-heat, application of current to the motor is suspended.
However, in the case a heat-sensitive fuse is employed, it is necessary to replace the fuse with a new one each time the motor overheats, and in the case of a motor in which a self-restoring type protective unit is incorporated, it is necessary to allow the motor to cool for a long period of time before it can be restarted. Furthermore, the conventional washing machine suffers from the difficulty that the occurrence of an abnormal condition cannot be detected until the motor actually over-heats, as a result of which the motor can eventually suffer breakdown of its electrical insulation.
If the condition of rotation of the rotary blades is detected and the energization of the motor controlled according to the condition of rotation thus detected, then the occurrence of an abnormal condition within the motor can be detected before the motor overheats. Upon elimination of the abnormal condition, the operation of the washing machine can be started again.
In such a washing machine in which the condition of rotation is detected, when an abnormal condition is sensed, the motor, and accordingly the rotary blades, is turned in the opposite direction from that in which it is trying to turn. If turning the motor and the rotary blades in the opposite direction does not eliminate the abnormal condition, the motor is stopped. This method is considerably effective in preventing motor failures in a washing machine.
In a single-tank type fully automatic washing machine, the washing tank (tub) is used also as a dehydrating (spin cycle) tank, and frequently the washing operation is carried out with the lid closed. Therefore, in the case where the motor is stopped as described above, if the operator is not near the machine, it is often difficult to know that the motor has stopped because the amount of noise issuing from the machine is low under normal operating conditions.
In almost all cases where the motor is locked, the cause is an excessively large quantity of clothes put in the machine. When the motor is locked by such a large load, the motor can be readily unlocked, and therefore it is necessary to notify the operator of the locking of the motor quickly; otherwise, the operator may waste a great deal of time.
SUMMARY OF THE INVENTION
In view of the foregoing, an object of the present invention is to provide a washing machine which overcomes the above-mentioned problems of the prior art, is high in safety, and which can be readily operated.
The foregoing and other objects of the invention have been achieved by the provision of a washing machine in which, when it is detected that the motor is in a locked state, it is attempted to turn the motor in the opposite direction a predetermined number of times, and if the motor remains in the locked state after being turned in the opposite direction in this manner, an indication is provided to the operator.
According to the invention, when the motor of the washing machine is locked, for instance, by an excessive quantity of clothes put into the washing machine, the motor is turned in the opposite direction, and if the motor is maintained locked even after turning it in the opposite direction, indicating means operates to indicate the occurrence of an abnormal condition. Therefore, the operator can detect the occurrence of the abnormal condition immediately and make the washing machine operate smoothly again, for instance, by decreasing the amount of clothes in the machine.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an explanatory diagram showing an example of a washing machine constructed according to this invention;
FIG. 2 is a block diagram showing a control unit in the washing machine of the invention; and
FIG. 3 is a flowchart provided for a description of the operation of the control unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the invention will now be described in detail with reference to the accompanying drawings.
FIG. 1 is an explanatory diagram showing an example of a washing machine constructed according to the invention. In FIG. 1, reference numeral 1 designates an agitator composed of a hollow cylinder having a number of through-holes 2 in its wall and agitating blades 3 which extend vertically and radially from the wall; 4, a dehydrating tank having the agitator 1 at its center and having a side wall with a plurality of through-holes formed therein; 6, a hollow annular balancer positioned along the upper end opening of the dehydrating tank 5; and 7, a water receiving tank provided outside the dehydrating tank 4 and having a water discharging outlet (not shown) to which a drain pipe is connected.
Further in FIG. 1, reference numeral 8 designates an electric motor coupled to a rotation transmitting section 12 through a speed reducing mechanism composed of a pulley 9, an endless belt 10, and a pulley 11. The rotation transmitting section 12 has dual drive shafts 12a and 12b which are controlled by a spring clutch mechanism 13. The outer drive shaft 12a is coupled to the dehydrating tank 4, and the inner drive shaft 12b to the agitator 1.
The motor 8 is provided with a speed detector 14 which detects the rotational speed (rpm) of the motor 8. In this embodiment, a tachometer generator may be employed as the speed detector 14.
The above-described components of the washing machine are contained within the outer case of the machine and are mounted through vibration damping members (not shown). A control unit 15, which is implemented with a microprocessor, and an operating panel 16, including operating switches 16b, 16b', etc., and indicating lamps 16a, 16a', 16a", etc., are provided on the upper part of the outer case.
Both the output of the speed detector 14 and the outputs of other detectors, such as a water level detector, are applied to the control unit 15. The outputs of the control unit 15 are applied to a drive circuit for the motor 8, the lamps 16a, 16b, etc., provided on the operating panel 16, a piezoelectric buzzer, a valve control circuit for a water supplying valve and water discharging valve, and other components.
The operation of the washing machine thus constructed will be described.
During a washing operation, the clothes to be washed, water, and detergent are put in the tank 4, and the power switch is turned on. The motor 8 is then rotated alternately in the forward direction and in the reverse direction, and accordingly, the agitator 1 is rocked. In this preferred embodiment, the speed reduction ratio of the pulleys 9 and 11 is 1/2, and a speed reducing unit forming a part of the rotation transmitting section 12 has a speed reduction rate of 1/6. Therefore, when the motor 8 makes eight revolutions in each of the forward and reverse directions, the agitator is rocked through an angle of 240°.
If an excessively large load of clothes is put in the tank 4, or if the clothes are snagged between the agitator 1 and the tank 4, the agitator 1 will be stopped and the motor 8 locked.
In this case, the rotation detector 14 detects the locked condition of the motor, and accordingly applies an output to the control unit 15. Thereupon, the control unit 15 causes the motor 8 to turn in the opposite direction. An attempt is made to turn the motor 8 in the opposite direction several times. If, during this period, the clothes are unsnagged (or other cause of such locking is removed), the washing operation is recommenced.
If, on the other hand, the motor is turned in the opposite direction several times but remains locked, the control unit 15 provides an output to suspend the application of current to the motor 8, and further provides an output to the operating panel 16 to issue an alarm for indicating the occurrence of an abnormal condition. As a result, in the control panel 16, for instance, the lamps 16a, 16a', 16a", etc., are made to flicker successively and the piezoelectric buzzer generates an alarm sound.
When the lamps flicker and the alarm sound is produced, the operator is notified that an exccessively large amount of clothes has been put in the dehydrating tank, etc., allowing the operator to correct the situation.
The above-described operations will be described in more detail.
As shown in FIG. 2, the control unit 15 includes a CPU (central processing unit) 15A, a ROM (read-only memory) 15B, a RAM (random-access memory) 15C, and an I/O (input/output) port 15D for inputting and outputting signals.
A counter A 17 counts how many times the motor has remained locked when the agitator is turned in the forward direction, while a counter B 18 counts how many times the motor has remained locked when the agitator 1 is turned in the reverse direction.
A program as shown in FIG. 3 is stored in the ROM. The locking of the motor during the washing operation is detected according to the program thus stored.
As shown in FIG. 3, in Step S1, an energization instruction to rotate the motor 8 in the forward direction outputted by the control unit 15. In Step S2, it is determined according to the output signal of the detector 14 whether or not the motor 8 is rotating in the forward direction. If the motor 8 is not rotating in the forward direction, the control unit 15 applies a signal to the counter A so that the content of the counter A is increased by one (Step S3). In succession, the control unit 15 supplies an energization instruction to cause the motor 8 to rotate in the reverse direction (Step S4).
In Step S5, the control unit 15 determines, according to a signal similar to that in Step S2, whether or not the motor 8 is rotating in the reverse direction. When it is determined that the motor 8 is rotating in the reverse direction in Step S6, the control unit 15 applies an instruction signal to the counter B so that the count value of the latter is increased by one.
In Step 7, the control unit 15 adds the count value of the counter A to that of the counter B to obtain a sum C (C=A+B).
In Step S8, it is determined whether or not the value C is larger than a predetermined value. If the value C is determined to be equal to or larger than the predetermined value, it is judged that an abnormal condition has occurred, and an instruction signal is then issued to indicate the occurrence of the abnormal condition. If, on the other hand, the value C is smaller than the predetermined value, the next Step S10 is effected.
In Step S10, it is determined whether or not the washing machine is still in the normal state; that is, it is determined whether or not a predetermined washing period of time has passed. If the washing period of time has not passed yet, Step S1 is effected again. If the washing period of time has passed, the next operation is carried out.
When, in Step S2 and Step S5, it is determined that the direction of rotation of the motor 8 is acceptable, Step S7 is effected. Thereafter, the control program is executed in the same manner as described above.
As is apparent from the above description, the washing machine of the invention is designed so that, when the motor is locked such as due to an excessively large quantity of clothes being put into the machine, the motor is rotated in the opposite direction a predetermined number of times, whereafter it is attempted to operate under normal conditions. If the washing machine cannot then be operated normally, application of current to the motor is suspended to ensure the security of the washing machine, and the indicating unit is operated to indicate the occurrence of the abnormal condition. Accordingly, even if the lid of a single-tank type washing machine is closed, the operator can promptly detect when the motor is locked. Therefore, the operator can quickly deal with the trouble, for instance, by decreasing the size of the load placed in the machine. | When it is detected that the motor for rotating the agitator of the machine is locked, the motor is turned in the forward direction and/or in the reverse direction a predetermined number of times. If the motor is still locked, an indicating unit is operated to indicate the occurrence of the abnormal condition. When the motor locked by an excessively large quantity of wash and the motor is not unlocked after the motor is turned in the opposite direction, the occurrence of the abnormal condition is indicated by an alarm unit. Therefore, the operator, informed of the presence of the abnormal condition immediately upon its occurrence, can rectify the problem, for instance, by decreasing the size of the washing load. | 3 |
TECHNICAL FIELD
[0001] The present invention relates generally to single-use flexible bioreactor capable of growing bacteria, mammalian cells, plant cells and viruses.
BACKGROUND OF THE INVENTION
[0002] Traditional bioreactors trace their design back to the vessels used in the fermentation industry for over 7,000 years. Most pharmaceutical solutions and suspensions manufactured on an industrial scale require highly controlled, thorough mixing to achieve a satisfactory yield and ensure a uniform distribution of ingredients in the final product. Agitator tanks are frequently used to complete the mixing process, but a better degree of mixing is normally achieved by using a mechanical stirrer or impeller (e.g., a set of mixing blades attached to a metal rod). Typically, the mechanical stirrer or impeller is simply lowered into the fluid through an opening in the top of the vessel and rotated by an external motor to create the desired mixing action.
[0003] One significant limitation or shortcoming of such an arrangement is the danger of contamination or leakage during mixing. The rod carrying the mixing blades or impeller is typically introduced into the vessel through a dynamic seal or bearing. This opening provides an opportunity for bacteria or other contaminants to enter, which of course can lead to the degradation of the product. A corresponding danger of environmental contamination exists in applications involving hazardous or toxic fluids, or suspensions of pathogenic organisms, since dynamic seals or bearings are prone to leakage. Cleanup and sterilization are also made difficult by the dynamic bearings or seals, since these structures typically include folds and crevices that are difficult to reach. Since these problems are faced by all manufacturers of sterile solutions, pharmaceuticals, or the like, the U.S. Food and Drug Administration (FDA) has consequently promulgated strict processing requirements for such fluids, and especially those slated for intravenous use.
[0004] In an effort to overcome these problems, the recent trend in the biotechnology industry is to use disposable plastic bags for a number of bioprocessing steps. Pre-sterilized disposable plastic bags eliminate the need for cleaning, sterilization and validation of the containers after each bioprocessing batch. Their use thus results in substantial saving in the cost of manufacturing of biopharmaceuticals.
[0005] Typically, one of the bioprocessing steps used in such manufacturing is growing cell culture(s) in the container, sometimes called a “bioreactor.” A traditional bioreactor is a sterile vessel made out of stainless steel or glass with highly controlled environmental parameters including temperature, pH, oxygen concentration, carbon dioxide concentration, which are monitored by permanent sensors built into the rigid vessel. During the cell growth process, the fluid in the bioreactor must also be agitated in order to maintain uniform distribution of temperature, gases and nutrients. As noted above, an impeller typically provides agitation with the blades housed on the shaft connected to an external motor and introduced inside the bioreactor through the dynamic seal in an effort to maintain sterility.
[0006] For normal cell growth certain concentration of dissolved oxygen must be maintained. Also, controlled introduction of other gases like carbon dioxide and nitrogen are normally necessary during bioreactor runs. The most efficient way of introducing gases in to bioreactor fluid is sparging, which involves forming small bubbles in the fluid. Such bubbles have large surface to volume ratio and thus can be dissolved more quickly than large size bubbles and thus provide a large kLA value (transport across fluid air interface).
[0007] Traditionally, porous solid materials (like titanium) associated with the rigid bioreactor provide sparging. Alternatively, metal sparging rings with small pre-drilled holes are permanently affixed in some rigid bioreactors. In both cases, the bioreactors are not readily disposable and thus must be cleaned and sterilized before reuse for bioprocessing.
[0008] In traditional rigid vessel bioreactor, the impeller, sparger, gas, temperature and pH sensors are reusable components that must be cleaned and sterilized after each batch. In the case of disposable bag bioreactors, it is desirable that all the fluid touching components are only used once. This presents the challenging task of providing inexpensive fluid-touching components that can be discarded along with the bag after use.
[0009] Another challenge is positioning the components of the bioreactor on the flexible bag. Unlike a rigid vessel, a bioreactor plastic bag (which is basically thin film) has no shape or structural rigidity. Traditionally, bioreactor components like impeller shafts, spargers, and sensors are housed on the rigid walls of the vessel by means of threads, bolts or clamps. Obviously, this method of component attachment does not work for plastic bags. To over come this, many manufacturers offer such solutions as levitating mixing devices, rocking and shaking of bags or compressing the bag externally to produce a wave motion inside the bag. While all of these methods provide some solutions to the problem, many problems in the mixing and aeration remain.
[0010] Thus, a need is identified for an improved manner of providing a mixing bag or flexible vessel with an integrated sparger and sensor(s). The improvement provided by the invention would be easy to implement using existing manufacturing techniques and without significant additional expense. Overall, a substantial gain in efficiency and ease of use would be realized as a result of the improvement, and would greatly expand the potential applications for which advanced mixing systems may be used, including bioprocessing.
SUMMARY OF THE INVENTION
[0011] A disposable bioprocessing apparatus intended for receiving a fluid in need of agitation and sparging using a gas is provided. The apparatus according to one aspect of the disclosure comprises a bag having an upper and a lower flexible wall forming an interior compartment capable of receiving and holding the fluid; the bag is divided into three compartments using two rows of proportionally spaced seals to create a middle compartment wherein a sparger is positioned for forming bubbles from the gas supplied to the fluid when present in the bag. The bag is rocked to transfer the fluid between the two larger compartments passing through a middle compartment wherein resides a sparger maximizing the gassing and mixing of the fluids. Alternately, the bag can be squeezed using flaps to cause movement of fluid across the three compartments. The seals are staggered between the rows in such a manner as to force fluid to take a deviated path to further improve mixing. The seals can be round or linear or both.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a side view of the apparatus. FIG. 1A is the starting position, FIG. 1B is the bioreactor rocked to the left and FIG. 1C is the bioreactor rocked to the right.
[0013] FIG. 2 is a top view of the apparatus.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Reference is now made to FIG. 1 , which discloses one embodiment of the apparatus of the present invention in the form of a bag, which is flexible and of a rectangular shape. The bag may be hermetically sealed and may have one or more openings or fittings 9 for introducing or recovering a fluid 2 or exhausting a gas 8 or introducing gas 10 through a sparger 4 . FIG. 1 further shows the bag with two rows of seals 3 to create three compartments, the left compartment 12 , the middle compartment 11 and the right compartment 1 ; the sparger 4 is positioned in the middle compartment 11 ; the bag is placed on a support surface 5 further containing heating element 6 and a rolling means 7 to rock the support surface 5 .
[0015] FIG. 1B shows that the bioreactor is rocked to the left and FIG. 1C shows the bioreactor rocked to the right.
[0016] The flexible the bag 3 may be made from one or more sheets of thin (e.g., having a thickness of between 0.1 and 0.2 millimeters) polyethylene film secured together to define a compartment for receiving the fluid. Preferably, the film used is clear or translucent, although the use of opaque or colored films is also possible.
[0017] Turning now to FIG. 2 , and as noted in the foregoing description, the two rows of proportionally spaced seals create three compartments; by keeping the rows of seals closer to the middle of the bag, a middle compartment is created which is just large enough to contain the sparger. The seal 3 may be in the shape of a dot or a dash and the two rows having staggered positions of seals to force the fluid through a distorted path.
[0018] The sparger 4 includes a porous surface attached to the gas inlet 10 ; the sparging surface can be made from stainless steel, perforated plastic, a membrane or aluminum oxide or any other hard or soft surface capable diffusing gas out as fine bubbles.
[0019] It may also be desirable to provide means in the bag to facilitate sensing characteristics of the fluid, such as the pH, oxygen content, temperature, etc. Preferably these sensors are of disposable type and embedded in the bag and remote receivers monitor the response to the sensors.
[0020] The preferred embodiment shown in FIG. 1 and FIG. 2 represents a means of mixing the fluid by rocking the bag; alternate means of mixing the fluid will include squeezing the right compartment to force the fluid to pass through the middle compartment and onto the left compartment and vice versa. The bag may be alternately shaken or subject to ultrasonic or mechanical vibrations.
[0021] The foregoing descriptions of various embodiments of the present inventions have been presented for purposes of illustration and description. These descriptions are not intended to be exhaustive or to limit the invention to the precise forms disclosed. The embodiments described provide the best illustration of the principles of the invention and its practical applications to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. | A flexible disposable bioreactor having three, stagger-baffled compartments wherein the middle compartment houses a sparging rod is described to provide the highest degree of sparging and mixing to produce biological products. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of priority from U.S. Provisional Application No. 60/400,092, filed on Jul. 31, 2002.
FIELD OF THE INVENTION
[0002] The invention is directed to a one-pot procedure for the 3-sulfenylation of indole-2-carboxylates.
BACKGROUND OF THE INVENTION
[0003] Substituted indole-2-carboxylates, more specifically 3-thioindole-2-carboxylates, have been explored for their therapeutic worth in many fields including the treatment of HIV, obesity, as well as their use as endothelin antagonists and anti-allergy agents. The addition of sulfur at the 3-position of indole-2-carboxylates relies on the nucleophilicity of that center. Sulfur substitution at the 3-position using various forms of electrophilic sulfur including disulfides and sulfenyl chlorides has been reported. Many of these methods suffer from various shortcomings, however. For instance, while the oxidation of a thiol to a disulfide using sodium perborate typically proceeds cleanly in near quantitative yields, the subsequent reaction with indole produces an equivalent of thiol as an undesired by-product. Alternatively, formation of the sulfenyl chloride using sulfuryl chloride or chlorine often results in poor yields and is limited by the stability of the resulting sulfenyl chloride. The harsh conditions associated with chlorination reactions are also incompatible with certain functionalities. The formation of sulfenyl chlorides using N-chlorosuccinimide has also been reported. This milder method of chlorination effectively expands the scope of functional group compatibility, enabling the formation of thermally unstable aliphatic sulfenyl chlorides, including those with ester groups, but may require the isolation of the requisite sulfenyl chloride.
[0004] As a result, a need remains for an efficient technique for the introduction of sulfur at the 3-position of indole 2-carboxylates via a sulfenyl chloride that can be generated and used in situ.
SUMMARY OF THE INVENTION
[0005] These and other needs are met by the present invention, which is directed to a one-step method for the sulfenylation of indole-2-carboxylates using in situ generated sulfenyl chlorides, comprising:
[0006] (a) mixing N-chlorosuccinimide and R 1 SH in a liquid for sufficient temperatures and for a sufficient time to generate R 1 SCl,
NCS+R 1 SH→R 1 SCl
[0007] wherein R 1 is (C 1 -C 6 )alkyl, (C 2 -C 6 )alkoxycarbonyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, (C 1 -C 6 )—S(O) m R a , —(C 1 -C 6 )—S(O) m NR b R c , (C 1 -C 6 )—NR b R c , or (C 1 -C 6 )—C(═O)—NR b R c , aryl, or heteroaryl, wherein (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, or (C 3 -C 7 )heterocycloalkyl is optionally partially unsaturated and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, aryl, or heteroaryl, is optionally substituted with aryl, aryl(C 1 -C 6 )alkoxy, aryloxy, arylcarbonyl, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, cyano, (C 1 -C 6 )alkoxy, (C 1 -C 6 ) alkanoyl, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C 6 )alkanoyloxy, —S(O) m R a , —S(O) m NR b R c , NR b R c , or —C(═O) NR b R c , wherein m is 1 or 2 and a, b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 )heterocycloalkyl, or aryl;
[0008] (b) combining an indole-2-carboxylate 1 with the mixture containing the sulfenyl chloride generated in step (a) to provide the sulfenylated indole 2
[0009] wherein R 1 is as provided in step (a);
[0010] R 2 is carboxy, tetrozolyl, (C 2 -C 6 )alkoxycarbonyl,
[0011] or —S(O) m R a , or —S(O) m NR b R c , NR b R c , or COR d , optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano, wherein R b and R c are each, independently H or (C 1 -C 6 )alkyl wherein m is 1 or 2 and a, b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 )heterocycloalkyl, or aryl; and
[0012] R 3 is H or (C 1 -C 6 )alkyl or (C 1 -C 6 )alkanoyl, optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano;
[0013] R 4 -R 7 are each independently H, halo, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, cyano, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, (C 1 -C 6 )—S(O) m R a , —(C 1 -C 6 )—S(O) m NR b R c , (C 1 -C 6 )—NR b R c , or (C 1 -C 6 )—C(═O)—NR b R c , (C 1 -C 6 )—C(═O)R1, S(O) m R a , S(O) m NR b R c , NR b R c , C(═O)—NR b R c , C(═O)R d aryl or heteroaryl, wherein (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, or (C 3 -C 7 )heterocycloalkyl is optionally partially unsaturated and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, aryl, or heteroaryl, is optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, cyano, (C 1 -C6)alkoxy, (C 1 -C 6 ) alkanoyl, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C6)alkanoyloxy, —S(O) m R a , —S(O) m NR b R c , NR b R c , or —C(═O) NR b R c , C(═O)R 1 wherein m is 1 or 2 and a, b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 ) heterocycloalkyl, heteroaryl or aryl, provided that not all of R 4 -R 7 are H; and
[0014] (c) mixing the mixture generated in step b for sufficient temperature and for sufficient time to generate the sulfide.
[0015] The invention also provides a one-step method for the sulfenylation of indole-2-carboxylates using in situ generated sulfenyl chlorides, comprising:
[0016] (a) mixing N-chlorosuccinimide with compound 3 in a liquid for sufficient temperatures and for a sufficient time to generate compound 4,
[0017] wherein R 3 is H or (C 1 -C 6 )alkyl or (C 1 -C 6 )alkanoyl, optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano;
[0018] R 4 - R6 and R 7 are independently H, halo, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, Cyano, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, (C1-C6)—S(O) m R a , —(C1-C6)—S(O) m NR b R c , (C1-C6)—NR b R c , or (C1-C6)—C(═O)—NR b R c , (C1-C6)—C(═O)R1, S(O) m R a , S(O) m NR b R c , NR b R c , C(═O)—NR b R c , C(═O) R 1 aryl or heteroaryl, wherein (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, or (C 3 -C 7 )heterocycloalkyl is optionally partially unsaturated and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, aryl, or heteroaryl, is optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, cyano, (C 1 -C 6 )alkoxy, (C 1 -C 6 ) alkanoyl, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C 6 )alkanoyloxy, —S(O) m R a , —S(O) m NR b R c , NR b R c , or —C(═O) NR b R c , C(═O)R1 wherein m is 1 or 2 and a, b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 ) heterocycloalkyl, heteroaryl or aryl, provided that not all of R 4 -R 7 are H;
[0019] R 8 and R 9 are independently H or (C 1 -C 6 )alkyl optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano;
[0020] n is 0-4; and
[0021] X is CR 7 R 8 , O, or NR b , wherein R b is H, acyl, or (C 1 -C 6 )alkyl, optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano; and
[0022] (b) allowing the sulfenyl chloride 4 generated in step (a) to provide the sulfenylated indole 5.
[0023] The advantages of this procedure include milder conditions than those associated with the use of corrosive chlorine or sulfuryl chloride, as well as fast reaction times, easy workup, and improved yields. The in situ formation method using NCS also enhances the scope of the reaction, previously limited by the stability and ease of isolation of the sulfenyl chlorides. The method also avoids the formation of one equivalent of wasted thiol that occurs when a disulfide is used as the electrophilic sulfur source.
[0024] In addition, the invention process provides a convenient approach to compounds that are useful as endothelin antagonists, as well as for HIV or obesity treatment.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The following definitions are used, unless otherwise described: halo is fluoro, chloro, bromo, or iodo. Alkyl, alkoxy, etc. denote both straight and branched groups; but reference to an individual radical such as “propyl” embraces only the straight chain radical, a branched chain isomer such as “isopropyl” being specifically referred to. When alkyl can be partially unsaturated, the alkyl chain may comprise one or more (e.g. 1, 2, 3, or 4) double or triple bonds in the chain.
[0026] Aryl and aryloxy denote an optionally substituted phenyl or phenoxy radical or an ortho-fused bicyclic carbocyclic radical having about nine to ten ring atoms in which at least one ring is aromatic. Heteroaryl denotes a radical of a monocyclic aromatic ring containing five or six ring atoms consisting of carbon and 1, 2, 3, or 4 heteroatoms each selected from the group consisting of non-peroxide oxygen, sulfur, and N(X) wherein X is absent or is H, O, (C 1 -C 4 )alkyl, phenyl or benzyl, as well as a radical of an ortho-fused bicyclic heterocycle of about eight to ten ring atoms derived therefrom, particularly a benz-derivative or one derived by fusing a propylene, trimethylene, or tetramethylene diradical thereto.
[0027] Arylcarbonyl refers to an optionally substituted phenyl radical attached to a carbonyl (“C═O”) moiety.
[0028] Aryl(C 1 -C 6 )alkoxy refers to an optionally substituted phenyl radical attached to a (C 1 -C 6 ) alkoxy fragment.
[0029] Heterocycloalkyl is a cyclic, bicyclic ring or bridged system having from 4-10 atoms, from one to four of which are selected from O, S, and N. Heterocycle includes non-aromatic groups such as morpholino and pyrrolidino. Preferred heterocycles are 5- or 6-membered mono-cyclic aromatic rings having 1 or 2 heteroatoms. Heterocycle also includes bicyclic rings such as benzofuran, isothiazolone, indole, and the like. Heterocycle also includes bridged ring systems. Typical groups represented by the term include the following, wherein the hyphen indicates the point of attachment. The groups above and below are optionally substituted on the peripheral nitrogens by alkyl groups as defined above or by nitrogen protecting groups as described by Green (referenced above). Other typically preferred groups include pyrimidine, pyridazine, pyrazine, oxazole, pyrazole, thiazole, and the like. Most preferred are: piperazine, pyrrolidine, morpholine, thiomorpholine, thiazole, oxazole, isoxazole, piperidine, and azetidine.
[0030] The alkyl, cycloalkyl, aryl, aryloxy, heteroaryl, and heterocycloalkyl groups can be substituted with one or more groups selected from aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano.
[0031] The compounds of the present invention are generally named according to the IUPAC or CAS nomenclature system. Abbreviations which are well known to one of ordinary skill in the art may be used (e.g., “Ph” for phenyl, “Me” for methyl, “Et” for ethyl, “h” for hour or hours and “rt” for room temperature).
[0032] It will be appreciated by those skilled in the art that compounds of the invention having a chiral center may exist in and be isolated in optically-active and racemic forms. Some compounds may exhibit polymorphism. It is to be understood that the present invention encompasses any racemic, optically-active, polymorphic, tautomeric, or stereoisomeric form, or mixture thereof, of a compound of the invention, which possesses the useful properties described herein, it being well known in the art how to prepare optically active forms (for example, by resolution of the racemic form by recrystallization techniques, by synthesis from optically-active starting materials, by chiral synthesis, or by chromatographic separation using a chiral stationary phase).
[0033] The carbon atom content of various hydrocarbon-containing moieties is indicated by a prefix designating the minimum and maximum number of carbon atoms in the moiety, i.e., the prefix C i -C j indicates a moiety of the integer “i” to the integer “j” carbon atoms, inclusive. Thus, for example, (C 1 -C 6 )alkyl refers to alkyl of one to six carbon atoms, inclusive.
[0034] Specific and preferred values listed below for radicals, substituents, and ranges, are for illustration only; they do not exclude other defined values or other values within defined ranges for the radicals and substituents.
[0035] Specifically, (C 1 -C 6 )alkyl can be methyl, ethyl, propyl, isopropyl, butyl, iso-butyl, sec-butyl, pentyl, 3-pentyl, or hexyl; (C 1 -C 6 )alkoxy can be methoxy, ethoxy, propoxy, isopropoxy, butoxy, iso-butoxy, sec-butoxy, pentoxy, 3-pentoxy, or hexyloxy; (C 1 -C 6 )alkanoyl can be acetyl, propanoyl, butanoyl, pentanoyl, 4-methylpentanoyl, or hexanoyl; (C 1 -C 6 )alkoxycarbonyl can be methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, pentoxycarbonyl, or hexyloxycarbonyl; aryl can be phenyl, indenyl, or naphthyl; and heteroaryl can be furyl, imidazolyl, triazolyl, triazinyl, oxazoyl, isoxazoyl, thiazolyl, isothiazoyl, pyrazolyl, pyrrolyl, pyrazinyl, tetrazolyl, pyridyl, (or its N-oxide), thienyl, pyrimidinyl (or its N-oxide), indolyl, isoquinolyl (or its N-oxide) or quinolyl (or its N-oxide); heterocycloalkyl includes, tetrahydrofuranyl, pyrrolidinyl, piperidinyl, and the like.
[0036] Both intermolecular and intramolecular variants of the sulfenylation reaction are encompassed by the scope of the instant application.
[0037] 1. Intermolecular Sulfenylation Reaction
[0038] Scheme 1 depicts the intermolecular variant of the sulfenylation method of the instant invention. In the first step of the reaction, the sulfenyl chloride is generated in situ by combining NCS with a thiol. In the second step of the reaction, an indole is combined with the in situ generated sulfenyl chloride to provide the sulfenylated indole product.
[0039] A. Thiol
[0040] A broad range of thiols may be used in the method of the present invention, including thiols wherein R 1 (C 1 -C 6 )alkyl, (C 2 -C 6 )alkoxycarbonyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, aryl, or heteroaryl, wherein (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, or (C 3 -C 7 )heterocycloalkyl, or aryl is optionally partially unsaturated and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, aryl, or heteroaryl, is optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, cyano, (C 1 -C 6 )alkoxy, (C 1 -C 6 ) alkanoyl, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C 6 )alkanoyloxy, NR b R c , or —C(═O) NR b R c , and b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 )heterocycloalkyl, or aryl.
[0041] One group of thiols that may be used in the method of the present invention include thiols wherein R 1 in R 1 SH is (C 1 -C 6 )alkyl or aryl, wherein (C 1 -C 6 )alkyl or aryl is optionally is optionally substituted with aryl, halo, cyano, (C 1 -C 6 )alkoxy, (C 1 -C 6 ) alkanoyl, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C 6 )alkanoyloxy, NR b R c , or —C(═O) NR b R c , and b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 )heterocycloalkyl, or aryl.
[0042] Another group of thiols that may be used in the method of the present invention include thiols wherein R 1 in R 1 SH is is (C 1 -C 6 )alkyl or aryl, wherein (C 1 -C 6 )alkyl or aryl is optionally is optionally substituted with halo, cyano, (C 1 -C 6 )alkoxy, (C 1 -C 6 ) alkanoyl, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C 6 )alkanoyloxy, NR b R c , or —C(═O) NR b R c , and b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, or aryl.
[0043] Still another group of thiols that may be used in the method of the present invention include thiols wherein R 1 in R 1 SH is t-butyl, phenyl, 2-, 3-, and 4-methoxyphenyl, benzyl, 2-, 3-, and 4-bromophenyl, 3-chloropropyl, 2-carbomethoxy ethyl, and 2-aminoethyl, wherein the amine moiety is protected as the BOC-amine or the like.
[0044] B. Indole 2-Carboxylates
[0045] Indole 2-carboxylates envisioned for use in the method of the present invention include compounds such as 2, depicted below.
[0046] In compound 1, R 2 can be carboxy, tetrazolyl, alkoxycarbonyl,
[0047] or —S(O) m R a , or —S(O) m NR b R c , NR b R c , or COR 1 , optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano, wherein R b and R c are each, independently H or (C 1 -C6)alkyl wherein m is 1 or 2 and a, b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 )heterocycloalkyl, or aryl;
[0048] Specific values for R 2 include carboxy, (C 2 -C 6 )alkoxycarbonyl, or
[0049] wherein R b and R c are each independently H or (C 1 -C 6 )alkyl; R 3 can be H or (C 1 -C 6 )alkyl. X can be H, halo or (C 1 -C 6 )alkoxy, and more specifically, carboxy, methoxycarbonyl, ethoxycarbony,
[0050] In compound 1, R 3 can be H or (C 1 -C 6 )alkyl or (C 1 -C 6 )alkanoyl, optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano. A specific value for R 3 is CH 2 CN.
[0051] In compound 1, R 4 -R 7 independently can be H, halo, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, Cyano, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, (C 1 -C6)—S(O) m R a , —(C1-C6)—S(O) m NR b R c , (C1-C6)-NR b R c , or (C1-C6)—C(═O)—NR b R c , (C1-C6)—C(═O)R1, S(O) m R a , S(O) m NR b R c , NR b R c , C(═O)—NR b R c , C(═O) R 1 aryl or heteroaryl, wherein (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, or (C 3 -C 7 )heterocycloalkyl is optionally partially unsaturated and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )heterocycloalkyl, aryl, or heteroaryl, is optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, cyano, (C 1 -C 6 )alkoxy, (C 1 -C 6 ) alkanoyl, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C 6 )alkanoyloxy, —S(O) m R a , —S(O) m NR b R c , NR b R c , or —C(═O) NR b R c , C(═O)R1 wherein m is 1 or 2 and a, b, and c are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 6 ) heterocycloalkyl, heteroaryl or aryl.
[0052] C. Procedure and Stochiometry
[0053] As provided earlier, the invention process for sulfenylating indole-2-carboxylates embraces both intermolecular and intramolecular variants. In the intermolecular variant of the sulfenylation process of the present invention, a thiol is first contacted with NCS to generate the corresponding sulfenyl chloride. As used herein, “contacted” means that the reaction components are typically mixed in a liquid to form a homogeneous or heterogeneous mixture. The liquid employed in the sulfenylation process of the present invention is a polar aprotic solvent. Preferably, the polar aprotic solvent is selected from tetrahydrofuran, diethyl ether, acetonitrile, nitromethane, chloroform, methylene chloride, monochloro ethane, 1,1, or 1,2 dichloroethane, 1,1,1 or 1,1,2 tricholoroethane, or 1,1,1,2, or 1,1,2,2 tetrachloroethane. More preferred solvents include methylene chloride or chloroform. Mixtures of solvents can also be used.
[0054] To generate the sulfenyl chloride from the thiol, about 1 equivalent of NCS is used for each equivalent of thiol, although a slight excess (e.g., 1.01 to 1.2 equivalents) of NCS may be used to drive the chlorination reaction to completion.
[0055] The NCS and thiol in the liquid must be mixed at a sufficient concentration to ensure conversion of the thiol to the sulfenyl chloride. Thus, concentrations of NCS and thiol are typically in the range of about 0.05 to about 0.3 M for each respectively. More preferably, concentrations of NCS and thiol are typically in the range of about 0.1 to about 0.25 M each respectively. Concentrations of NCS and thiol are typically in the range of about 0.15 to about 0.2 M for each respectively.
[0056] The NCS and thiol in the liquid must be mixed for sufficient time to ensure conversion of the thiol to the sulfenyl chloride. Thus, reaction times are typically in the range of 5 minutes to an hour. More preferably, reaction times are typically in the range of 10 minutes to 30 minutes. More preferably, reaction times are typically in the range of 12 minutes to 20 minutes.
[0057] The NCS and thiol are mixed in the liquid at temperatures that are low enough to minimize or prevent undesired side reactions or NCS or sulfenyl chloride decomposition. Thus, the temperature of the mixture is typically in the range of −90 to −25° C. More preferably the temperature is in range of −80 to −20° C. More preferably the temperature is in the range of −79 to −70° C.
[0058] A solution of the indole-2-carboxylate in a solvent is then combined with the sulfenyl chloride generated during the first step of the invention method. Typically, the indole is added as a solution in a polar aprotic solvent such as methylene chloride, although other solvents such as diethylether, tetrahydrofuran, chloroform, or mixtures thereof, may be used. The solvent is used in an amount sufficient to produce a homogeneous mixture of the indole in the solvent. Typical concentrations of the indole in the solvent are thus in the range of about 0.1 to about 1.0 M. More preferably, concentrations are in the range of about 0.2 to about 0.9 M. More preferably, concentrations are in the range of about 0.3 to about 0.7 M The mixture of the indole in the solvent is added to the chilled mixture of the sulfenyl chloride at a rate sufficient to maintain the reaction temperature at below −70° C. The completion of the addition step culminates in the formation of a mixture containing sulfenyl chloride and indole. Typically, an excess of sulfenyl chloride is used based on the equivalents of indole used. Thus, about 1.01 to about 1.5 equivalents of sulfenyl chloride are used for each equivalent of indole used. More preferably, about 1.05 to about 1.3 equivalents of sulfenyl chloride are used for each equivalent of indole used. More preferably, about 1.09 to about 1.25 equivalents of sulfenyl chloride are used for each equivalent of indole used.
[0059] The mixture containing the sulfenyl chloride and indole is maintained at a temperature between −79 to −70° C. for up to about 15 to 60 minutes and then is allowed to warm to about 0° C. over the course of about 1 to 2 hours, although longer times may be necessary. Removal of the solvent by evaporation provides the crude sulfenylateted indole as a solid residue. The residue is then suspended in water and filtered. The sulfenylated indole product is collected as a solid, which may be further purified by recrystallization, in 40-100 percent yields generally.
[0060] In a typical procedure, the sulfenyl chloride of the desired thiol is formed in situ using N-chlorosuccinimide at −78° C. The indole is added after 15 minutes and the reaction is warmed to 0° C. over one hour. The solvent is evaporated and the residue suspended in water. Filtration of the mixture yields the desired product in high purity.
[0061] The sulfenyl chlorides prepared by the invention method are readily used in the direct functionalization of indoles. As Table 1 below indicates, the scope of this invention process possesses greater flexibility than other reported methods because the indole nitrogen does not require protection.
TABLE 1 Sulfenylations of indole-2-carboxylates Entry X R1 R2 HS-R3 Yield 1 OMe H CO 2 Me 97 2 OMe Me CO 2 Me 0 3 OMe Me CO 2 Me 86 4 OMe H CO 2 Me 94 5 OMe Me CO 2 Me 99 6 OMe Me CONH 2 96 7 OMe Me CONH 2 91 8 OMe Me CONH 2 0 9 H H CO 2 Et 81* 10 H H CO 2 Et 76* 11 H H CO 2 Et 64* 12 F H CO 2 Et 51* 13 F H CO2Et 48*
[0062] Table 1 also indicates that there is not a significant difference between yields in reactions employing protected versus unprotected indole cores. Moreover, a variety of thiols may be used, with the exception of tert-butyl thiol, which provides no reaction. Also, substitution in the indole does not appear to impede the sulfenylation reaction. However, the sulfenylation method has steric restrictions. For example, the reaction does not work for t-butyl thiol (entries 3 and 9 in Table 1).
[0063] 2. Intramolecular Sulfenylation Reaction
[0064] Scheme 2 depicts the intramolecular variant of the sulfenylation method of the instant invention. The requisite thiol 2 is first prepared from the corresponding indole carboxylic acid using standard methodology. The sulfenyl chloride is next generated in situ, and then undergoes cyclization to provide the sulfenylated product 4.
[0065] A. Thiol-Substituted Indole
[0066] A broad range of thiol-substituted indoles 4 may be used in the intramolecular variant of the present invention, including thiol substituted indoles wherein R 3 -R 6 and X have any of the meanings provided above.
[0067] In addition, R 8 and R 9 independently in the thiol-substituted indole 4 can be H or (C 1 -C 6 )alkyl optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano. Specific values for R 8 and R 9 include methyl, benzyl, isopropyl, and butyl and isobutyl.
[0068] Finally, X in the thiol-substituted indole 4 can be CR 7 R 8 , O, or NR b , wherein R b is H or (C 1 -C 6 )alkyl, optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano.
[0069] A group of thiol-substituted indoles for use in the method of the instant invention includes compounds wherein one of R 4 -R 7 is halo or alkoxy and the others are independantly are H or (C 1 -C 6 )alkyl, optionally substituted with aryl, aryloxy, heteroaryl, heteroaryloxy, hydroxy, nitro, halo, or cyano; R 7 and R 8 are independently H or methyl; n is 1, 2, or 3; X is H, halo, or methoxy; and Y us O or NR b , wherein R b is H, methyl, or acyl.
[0070] B Procedure and Stochiometry
[0071] As in the intermolecular variant of the sulfenylation process, in the intramolecular variant of the sulfenylation process, the thiol-substituted indole carboxylate is first contacted with NCS to generate the corresponding indole sulfenyl chloride. As used herein, “contacted” means that the reaction components are typically mixed in a liquid to form a homogeneous or heterogeneous mixture. The liquid employed in the sulfenylation process of the present invention is a polar aprotic solvent. Preferably, the polar aprotic solvent is selected from tetrahydrofuran, acetonitrile, nitromethane, chloroform, methylene chloride, monochloro ethane, 1,1, or 1,2 dichloroethane, 1,1,1 or 1,1,2 tricholoroethane, or 1,1,1,2, or 1,1,2,2 tetrachloroethane. More preferred solvents include methylene chloride or chloroform. Mixtures of solvents can also be used.
[0072] To generate the sulfenyl chloride from the thiol-substituted indole, about 1 equivalent of NCS is used for each equivalent of thiol-substituted indole, although a slight excess (e.g., 1.01 to 1.2 equivalents) of NCS may be used to drive the chlorination reaction to completion.
[0073] The NCS and thiol-substituted indole in the liquid must be mixed at a sufficient concentration to ensure conversion of the thiol to the sulfenyl chloride. Thus, concentrations of NCS and thiol are typically in the range of about 0.05 to about 0.3 M each respectively. More preferably, concentrations of NCS and thiol are typically in the range of about 0.1 to about 0.25 M each respectively. Concentrations of NCS and thiol are typically in the range of about 0.15 to about 0.2 M each respectively.
[0074] The NCS and thiol-substituted indole in the liquid must be mixed for sufficient time to ensure conversion of the thiol to the sulfenyl chloride. Thus, reaction times are typically in the range of 5 minutes to an hour. More preferably, reaction times are typically in the range of 10 minutes to 30 minutes. More preferably, reaction times are typically in the range of 12 minutes to 20 minutes.
[0075] The NCS and thiol-substituted indole are mixed in the liquid at temperatures that are low enough to minimize or prevent undesired side reactions or NCS sulfenyl chloride decomposition. Thus, the temperature of the mixture is typically in the range of −90 to −25° C. More preferably the temperature is in range of −80 to −20° C. More preferably the temperature is in the range of −79 to −70° C.
[0076] The indole sulfenyl chloride is maintained at a temperature between −79 to −70° C. for up to about 15 to 60 minutes and then is allowed to warm to about 0° C. over the course of about 1 to 2 hours, although longer times may be necessary. Removal of the solvent by evaporation provides the crude sulfenylateted indole as a solid residue. The residue is then suspended in water and filtered. The cyclized sulfenylated indole product is collected as a solid, which may be further purified by recrystallization.
[0077] A particular variant of the intramolecular method is depicted in Scheme 3.
[0078] Thus, thioamide 7 was prepared from the corresponding indole-2-carboxylic acid 6 and 2-amino-thioethane via CDI amidation conditions. Reaction of 7 with NCS leads to cyclization and formation of previously unavailable thioazepines 8. The intramolecular reaction proceeds even for the sterically hindered gem-dimethyl substrate. A slight decrease in the yield of this reaction can be explained by chlorination of the 3-position of the indole as a side reaction.
[0079] 3. Preparation of an Endothelin Antagonist Using the Invention Process
[0080] The invention process is easily adaptable to the synthesis of an array of biologically active molecules, for instance, compounds which are endothelin antagonists, or are useful in HIV or obesity treatment. For example, 1-Benzyl-3-(3-methoxy-phenylsulfanyl)-1H-indole-2-carboxylic acid 12 is an endothelin antagonist, as disclosed in U.S. Pat. No. 5,482,960. The compound can be prepared as provided in Scheme 4. Thus, indole-2-carboxylic acid methyl or ethyl ester is sulfenylated according to the invention process to provide 3-(3-Methoxy-phenylsulfanyl)-1H-indole-2-carboxylic acid 10. N-benzylation of compound 10 according to the procedure disclosed in U.S. Pat. No. 5,482,960 can give rise to compound 11, which may be hydrolyzed according to U.S. Pat. No. 5,482,960 using LiOH or any other procedure readily available to the skilled artisan to provide the target compound 12.
[0081] In conclusion, the invention provides a method for introduction of sulfur at the 3-position of indoles. This mild method is tolerant of a wide range of indole and thiol substrates that contain sensitive functionality. The high yielding reaction provides straightforward access to a wide array of potentially valuable targets.
[0082] The following examples are intended to illustrate various embodiments of the invention and are not intended to restrict the scope thereof.
EXAMPLES
Example 1
[0083] 3-Methoxy-phenylsulfanyl-1H-indole-2-carboxylic acid methyl ester
[0084] To a cooled solution of N-chlorosuccinimide (2.74 g, 20.6 mmol) in dichloromethane (125 mL) at −78° C., 3-methoxythiophenol (2.55 mL, 20.6 mmol) was added. The reaction was warmed to 0° C. over 15 minutes and a solution of indole-2-carboxylic acid methyl ester (3 g, 17.1 mmol) in dichloromethane (25 mL) was added. The reaction stirred at 0° C. for 1 hour, then concentrated under reduced pressure. The residue was suspended in H 2 0 and stirred for 30 minutes. The solid was filtered and recrystallized from EtOAc/hexanes to yield the desired product (3.22 g, 60%). m.p.155-156° C. 500 MHz 1 H NMR (DMSO-d 6 ) δ 7.50 (d, 1H, J=7.6 Hz), 7.38 (d, 1H, J=7.6 Hz), 7.29 (t, 1H, J=7.1 Hz), 7.08 (m, 2H), 6.64 (d, 1H, J=7.6 Hz), 6.56 (m, 2H), 3.83 (s, 3H), 3.60 (s, 3H). MS nvz 314 (M+1). Anal. Calc'd for C 17 H 15 NO 3 S C, 65.16; H, 4.82; N, 4.47; found: C,65.16; H,4.92: N, 4.40
Example 2
[0085] 4-Bromo-phenylsulfanyl-1H-indole-2-carboxylic acid methyl ester
[0086] Prepared by the method described in Example 1 from 4-bromothiophenol to provide the desired ester (67%). 500 MHz 1 H NMR (DMSO-d 6 ): 12.47 (s, 1H), 7.51 (d, J=8.3 Hz, 1H), 7.39 (d, J=8.1 Hz, 1H), 7.36 (d, J=8.8 Hz, 2H), 7.30 (dd, J=8.3, 8.1 Hz, 1H), 7.09 (dd, J=8.3, 8.1 Hz, 1H), 6.96 (d, J=8.8 Hz, 2H), 3.82 (s, 3H). MS n/z 362, 364 (M+1).
Example 3
[0087] 3-m-Tolylsulfanyl-1H-indole-2-carboxylic acid methyl ester
[0088] Prepared by the method described in Example 1 from 3-methylthiophenol to provide the desired ester (63% yield). 400 MHz 1 H NMR (DMSO-d 6 ) δ 7.50 (d, 1H, J=7.6 Hz), 7.38 (d, 1H, J=7.6 Hz), 7.29 (t, 1H, J=7.1 Hz), 7.08 (m, 2H), 6.64 (d, 1H, J=7.6 Hz), 6.56 (m, 2H), 3.83 (s, 3H), 3.60 (s, 3H). MS m/z 314 (M+1).
[0089] All publications, patents, and patent documents are incorporated by reference herein, as though individually incorporated by reference. The invention has been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention. | A highly efficient one-pot procedure for 3-sulfenilation of indole 2-carboxylates is described. Treatment of thiols with N-chlorosuccinimide at −78° C. in CH 2 Cl 2 affords sulfenyl chlorides in situ that readily react with indole 2-carboxylates to give 3-thioindoles in high yields. This new method is milder, produces less waste, and is compatible with a wide range of thiol and indole functionality. | 2 |
BACKGROUND OF THE INVENTION
This invention relates generally to a mechanism for deadlocking a door member to a door frame member in such manner as to accommodate sudden opening of the door member as by sudden pushing of an associated panic bar. More particularly, it concerns a temperature responsive mechanism that prevents opening of the door in case of fire.
Safety exit doors are widely used, and they commonly incorporate lock mechanisms which lock the doors to door frames, and which are releasable by operation of panic bars. See U.S. Pat. Nos. 1,638,748; 4,130,306; 4,083,590; and 4,368,905. U.S. Pat. No. 4,838,587 to Choi discloses an improved mechanism for controllably deadlocking a door to a door frame, for panic release.
There is need for simple, compact, reliable mechanisms of this type, which are readily installable upon such doors and door frame members to thereby provide safety exit door operation, and which also block opening of the exit door in case of fire. There is also need for deadlocking mechanisms wherein only one latch and its operating rod are needed on a door, as adjacent the door top.
SUMMARY OF THE INVENTION
It is a major object of the invention to provide door locking and unlocking safety mechanism comprising:
a) a push mechanism actuator means to be carried by the door,
b) a single rod operatively connected with the push mechanism to be displaced by operation of the push mechanism, and
c) door latch mechanism above the level of said push actuator means, and operable to latch and unlatch the door in response to movement of the single rod,
As will be seen, the door latch mechanism is typically on the door, and is the only door latch mechanism on the door.
Also temperature responsive blocking means may be associated with the latch mechanism to block operation of the latch to unlatch the door, in response to a predetermined increase in ambient temperature.
It is another object to provide the temperature responsive blocking means to include a spring-urged element and a heat fusible part blocking spring-urged movement of the element into a position to block rod movement that would otherwise unlatch the door.
It is a further object to provide a single rod to extend in cooperation with a single latch mechanism on the door, and to be movable from a first location in which a latch dog is blocked to prevent pivoting of a latch to release a bolt, to a second location in which the dog is unblocked, to allow latch pivoting. The single rod is typically carried by the door member for endwise vertical movement, there being a shoulder on the rod engageable by the temperature responsive blocking means in response to a predetermined increase in ambient temperature, as during a fire. The single rod is normally movable vertically endwise by the push mechanism actuator means; the latter, however, typically melting at high temperature during a fire, whereby the rod, which would otherwise drop by gravity action, is prevented from dropping by operation of the temperature responsive blocking means.
These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:
DRAWING DESCRIPTION
FIG. 1 is a perspective view showing the mechanism of the invention in relation to a panic bar and actuating means therebetween;
FIG. 2 is a front elevational view of the deadlocking mechanism;
FIG. 3 is a side elevation taken on lines 3--3 of FIG. 2;
FIG. 4 is a top plan view of lines 4--4 of FIG. 2;
FIG. 5 is a view like FIG. 4 showing a bolt in captivated position;
FIG. 6 is an elevation showing the bolt captivated position;
FIG. 7 is an enlarged elevation showing details of a heat fusible rod movement blocking device; and
FIG. 8 is a section on lines 8--8 of FIG. 7.
DETAILED DESCRIPTION
In FIG. 1, a locking bolt 10 is carried by, and projects rigidly and freely downwardly from, a door frame upper transverse member 11, i.e., at the general level of the top 12a of a door member 12. Mechanism 13, in block form, and incorporating the invention, is attached to the exterior uppermost side 12b of the door member. A panic bar 17 extends horizontally and is carried by the door at a lower "manual push" level; and block 14, also carried by the door, represents actuator mechanism between the bar 17 and a vertically movable part 15, such as a single rod acting as a latch blocking and unblocking part, as will appear.
Arrows 16 indicate such rod up and down movement, as controlled by the panic bar. See for example the structure in U.K. Patent No. 2080391A. However, only one latch operating rod, extending above block 14 at 15, is utilized, in the interests of simplicity, safe operation, ease of installation, and lower cost.
Referring now to FIGS. 2-6, the mechanism 13 includes a hollow, metallic, box-like body 19 having a side wall 20 attachable to the side of the door 12, as via fasteners 21' receivable through holes 22' in side wall 20. The body also includes upright flanged walls 21 and 22 integral with wall 20 and bent at 90° thereto. Walls 21 and 22 serve to support wall 23 if and when 23 bends downward under load. Further, the body includes top and bottom flanged walls 23 and 24 integral with wall 20, and bent at 90° thereto. See for example bends 23a and 24a. A further upright wall 25 is integral with top wall 23, and bent upwardly at 25a, for purposes as will appear.
A rotary latching means 26 is carried by the body, and typically by top wall 23, to pivot about an axis 28, which extends parallel to the axis 27 of bolt 10, both axes typically extending vertically. The latching means includes a latch 29 in the form of a plate, which is generally C-shaped in horizontal plane, and forms a recess 30 having a C-shaped inner wall 30a' defined by arms 31 and 32 of the C-shaped latch. The recess 30 is adapted to relatively receive the bolt 10 as the door member closes or pivots relatively toward the plane of the door frame member 11, whereby the bolt engages the inner edge 30a' of the arm 31, and forcibly pivots the latch plate about the second axis 28, as referred to, and into FIG. 5 position.
In that position, the bolt is confined by the C-shaped latch 29, and also by the upwardly projecting wall 25, referred to above. Thus, the bolt relatively moves from FIG. 4 position to FIG. 5 position, generally parallel to wall 25. In actuality, the wall 25 moves relative to the bolt, which is typically carried by the fixed position frame member 11.
Pivoting of the latch is accommodated by a pivot shaft 33 carried by the top plate 23 to project upwardly, for spacing the latch 29 well above the top plate 23. Spacers 34-38 are mounted on shaft 33, and confined in stacked relation between 23 and 29, as shown. Other spacers may be employed, such as using one mechanism or spacer only. A predetermined torsion spring 40 is located beneath plate 23 and wrapped about shaft 33, to urge, the shaft, latch plate, and spacers in one direction in FIGS. 4 and 5, and toward FIG. 5 position. Thus, as the bolt centers the recess 30, it rotates the latch in the opposite direction, and against the force of the spring, further tensioning the latter. A head 41 on the lower end of the shaft holds the spring between 41 and 23. Torsion spring arm 42 engages the wall 23; and the opposite arm 43 of the spring is attached to the head 41.
Of particular advantage is the fact that the space 45 between the latch plate 29 and the top wall 23 accommodate bolts of different lengths, i.e., that project downwardly to different extents into that space, as the bolt moves relatively into the recess 30 during door closing. Thus, the wide tolerance levels for interengaging parts, upon latching and unlatching, are provided for.
A blocking and unblocking part, as in the form of rod 15 previously referred to, extends in cooperating relation with the body 19. As shown, the polygonal cross section rod 15 extends upwardly into the hollow interior of the body, i.e., between walls 21 and 22, as via polygonal (square) cross section guide openings 47 and 48 through the walls 23 and 24. The rod uppermost extent 15a in FIG. 5 extends into laterally blocking relation or with a latch dog 50 integral with and projecting radially outwardly of spacer 35, which is rotatably attached to shaft 33, as via engagement therewith at flat area 51.
When the rod extent 15a retracts downwardly below the level of the latch dog, as by panic pushing of the bar 17, the spring urges the latch toward FIG. 4 position, suddenly freeing the latch from the bolt, and allowing rapid opening of the door. Also, the force pushing bar 17 accelerates freeing of the latch from the bolt. Alternatively, when the rod upper extent 15a engages the dog 50 at 50a in FIG. 5, the door is positively latched to the bolt 10.
The plate 34 defines two angularly spaced stops or stop shoulders 70 and 75 (see FIG. 5), alternately engageable with a stop pin 77 integral with top wall 23, thereby to limit rotation of the latch at FIG. 4 and FIG. 5 positions.
As shown in FIG. 2, temperature responsive blocking means is provided at 80, in association with the latch mechanism, to block operation of the latch to unlatch the door, in response to a predetermined increase in ambient temperature. Device 80 operates to project a blocking part from stored or retracted position, indicated at 81, to extended position, indicated by broken lines 81', in which it projects beneath a shoulder 82 on the rod 15, preventing dropping or lowering of the rod, and thereby preventing unlatching of the mechanism that would otherwise allow opening of the door. This is desired in case of fire, since a closed door blocks the spread of the flames.
The latch mechanism parts and the rod typically consist of steel to resist melting during a fire. Device 80 is indicated generally in FIG. 2, to represent a family or class of usable temperature responsive devices that would prevent rod dropping, i.e., endwise rod movement that would effect unlatching.
FIGS. 7 and 8 show a particular temperature responsive blocking device, within the family of such devices, as referred to, and which is preferred. As shown, it includes a spring-urged element in the form of an arm 83 pivotally mounted on bottom wall 24, to swing about upright axis 89'. A heat-fusible part 84 normally blocks spring-urged movement of the arm 83 into a position beneath shoulder 82a on the rod 15. In that arm released position, indicated by broken lines 83' in FIG. 8, the arm blocks rod downward movement that would otherwise release the door. The panic bar may be melted by the fire, along with rod-actuating mechanism in block 14 (see FIG. 1); however, the rod does not then drop, as by gravity, to unlatch the latch, since the arm 83, released by melting of part 84, then extends beneath rod shoulder 82a to prevent rod dropping.
Fusible part 84 may consist of plastic (synthetic resin) that melts at elevated temperatures, such as temperature above 500° F., encountered during a fire. Part 84 is shown as a cylinder having a stem 84a received in an opening 88 in bottom wall 24, whereby the cylinder extends in front of the tip of arm 83 to prevent its swinging about axis 89. The arm has a pivot axle 90 also received in an opening 91 in wall 24.
A torsion spring 92 is wound about an upward extension 90a of the axle, and urges the arm clockwise in FIG. 8. See torsion spring end 92a bearing against the arm 93, and end 92b bearing against wall 22. Shoulder 82a on the rod may be provided by a steel screw 82 attached to the rod to project outwardly from the rod side, as shown. | A door locking and unlocking safety mechanism comprising a push mechanism actuator structure to be carried by the door; a single rod operatively connected with the push mechanism to be displaced by operation of the push mechanism; door latch mechanism operable to latch and unlatch the door in response to movement of the single rod; and temperature response blocking structure associated with the latch mechanism to block operation of the latch to unlatch the door, in response to a predetermined increase in ambient temperature. | 4 |
[0001] This invention relates to an insect, more particularly termite and waterproof barrier.
BACKGROUND OF THE INVENTION
[0002] Insects such as ants and termites can enter a building structure through very small openings, cracks and the like, often these gaps or openings not being readily discernable. While the invention is applicable to the provision of a barrier to insects the invention is particularly directed to the provision of a termite and waterproof barrier.
[0003] Termites usually enter a building from the ground, and physical barriers have been proposed to prevent the entry of termites into the building. These include concrete slabs, ant caps on posts or pillars supporting the building, and steel mesh. These physical barriers can be used in combination with chemical termiticide treatment of the soil around the footings and penetrations.
[0004] Recent concern about the environmental effect of various termiticides such as organophosphates and organochlorines have resulted in restrictions being placed on the use of chemical treatment of the soil and or building structure.
[0005] It is an object of the invention to provide a physical barrier to prevent and or deter the entry of termites into a building.
[0006] A further object of the invention is to provide a composition which can be applied to areas of a building to close a possible entry point into the building.
[0007] A still further object of the invention is to provide a physical barrier in the form of a fabric coated or impregnated with the composition to close possible entry points.
[0008] A still further object of the invention is to provide a coated or impregnated fabric and to adhere the fabric to the structure by an application of a layer of the composition.
[0009] A still further object of the invention is to provide a termite and waterproof barrier having sufficient flexibility and elasticity to accommodate for any relevant movement between portions of the structure.
BRIEF STATEMENT OF THE INVENTION
[0010] There is provided according to the invention a waterproofing and insect and termite composition comprising inorganic additives, fibres, and a curable or settable component such as an acrylate latex, whereby the composition when applied as a thick paint or coating forms when it cures a waterproof, flexible membrane resistant to insects and termites.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a view showing two possible entry points into a building,
[0012] FIG. 2 is a view showing the barrier applied between two portions of the building,
[0013] FIG. 3 shows one form of the fibre reinforced membrane,
[0014] FIG. 4 shows the barrier applied to a brick veneer construction,
[0015] FIG. 5 shows the barrier applied to an infill full brick construction,
[0016] FIG. 6 shows an alternate barrier to the infill brick construction,
[0017] FIG. 7 shows the barrier applied to foundation and footing slab, and
[0018] FIG. 8 shows an alternate barrier to the foundation and footing slab.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The invention uses a composition that can be supplied in the form of a liquid, paste, gel or other similar form that can be applied to cracks, holes or gaps in building structures to form a waterproof and insect, particularly termite proof barrier.
[0020] In its preferred form the composition comprises an acrylic latex with inorganic additives and polyester fibres dispersed in the latex to form a composition that is waterproof and self-curing, resistant to insects, particularly termite attack.
[0021] One example of the composition can include
% w/w Calcium Carbonate 25 Polyester fibre 15 Styrene/butyl acrylate latex 40 Iron oxide pigment 2 Titanium dioxide 2.5 Plasticiser 1 Stabiliser 1 Biocide 0.1 Water to 100%
[0022] In another preferred form of the invention another composition can include the following:
% w/w Styrene-acrylic polymer 60 Calcium Carbonate 25 Titanium Dioxide 5 Pigment 2 Propylene Glycol 2 Polymeric dispersant 1 Boric Acid 0.5 Water up to 100%
[0023] In a still further preferred form of the invention the composition can include:
Styrene-acrylic polymer 50 Calcium Carbonate 20 Glass Fibre 12 Titanium Dioxide 5 Pigment 5 Ethylene Glycol 3 Boric Acid 1 Dispersant 1 Biocide 0.15 Water up to 100%
[0024] Preferably the fibres are chopped fibres typically with a length of 1-3 mm and a diameter of 0.01 to 0.1 mm although other lengths and diameters can be used. The fibres can be of any material that is inedible to termites such as nylon, polyester, polyethylene, polypropylene, glass fibre etc. Cellulose fibres are not suitable.
[0025] The composition can be varied widely and still remain functional.
[0026] The inorganic constituents can be varied in total amount, relative proportions and chemical composition. For any given chemical entity the amount can be varied from about 0% to about 50% of the total composition. The number of possible additives is vast and encompasses practically any inorganic salt, oxide or mineral. Practically, the choice is limited to readily available materials with low solubility in water, low toxicity, and no adverse environmental impact. Examples include calcium carbonate, titanium dioxide, iron oxides (haematite and magnetite), magnesium oxide, magnesium carbonate, silica, silicates etc. In addition it is possible to use other fillers such as plastic beads, metal filings, carbon (in the form of graphite, char, charcoal, carbon black etc) in place of or as well as inorganic constituents.
[0027] The composition includes a settable or curable sealant. Suitable materials include acrylates, co-polymers, bitumen, water based silicones, polyurethane, chalking compounds, resins, latex and adhesives. The settable or curable sealant is essential to the performance of the product and can comprise 20 to 80% by weight of the product, typically about 40% to 60% by weight.
[0028] Minor constituents of the composition include catalysts, plasticisers, UV stabilisers and biocides. These additives are well known in this type of application and can be selected from a wide variety of materials. For example, glycols, polyethylene glycols, surfactants and phthalate esters can function as plasticisers and stabilisers; isothiazolines and formaldehyde are well-known examples of biocides used in aqueous formulations.
[0029] Many other minor additives can be incorporated in the product to modify its characteristics without altering its fundamental properties. For example, organic dyes or pigments could be used to extend the range of colours for decorative effects. Coarse materials such as sand or carborundum could be added to give the material non-slip properties. Most importantly termiticides could be added to enhance the termite resistant properties of the material. Examples of termiticides include organophosphates (such as chlorpyrifos) organochlorines (such as heptachlor), natural and synthetic pyrethroids (such as deltamethrin and permethrin) and inorganic compounds (such as compounds of arsenic, copper and boron).
[0030] However, organic compounds such as organophosphates, organochlorines and pyrethroids are intrinsically chemically unstable and liable to lose efficacy over a period substantially less than the lifetime of the barrier or liable to leach out of the barrier into the local environment, which in the case of a cavity wall treatment could be most undesirable. Inorganic compounds have the virtue of remaining efficacious as long as the barrier remains intact i.e., for the lifetime of the barrier and not likely to leach out of the barrier over a period of time. Arsenic and copper are not considered to be environmentally acceptable and therefore the preferred additive is a boron containing compound. Examples of boron containing compounds include boric acid, borax, borates, tetraborates and borohydrates although without limitation thereto.
[0031] The preferred boron-containing compound is boric acid. Preferably boric acid is present at concentrations of 2.0 g/kg to 80 g/kg or more. The preferred concentration is about 30 g/kg, more particularly 5 to 10 g/kg.
[0032] The composition can be used in conjunction with construction materials such as stainless steel mesh, fibre glass, woven plastic mesh (such as shade cloth, flywire, and the like) geotextile and other similar fabrics to form a water proof and insect, particularly termite, proof damp course and termite barrier in building cavities.
[0033] When used in conjunction with building materials such as geotextile fabric, the composition can be coated to the fabric in-situ, or the fabric can be precoated and supplied in a cured form as a waterproof, termite-proof membrane. In either case the membrane is made to adhere to the building materials by application of the composition in a liquid form followed by either the prepared membrane or the freshly coated fabric. The membrane when coated with the composition and cured is flexible, has good tensile strength so that it cannot be easily torn. Also the membrane has a slight degree of elasticity. The following example will serve to clarify the method of application of the composition:
[0034] Referring to FIG. 1 illustrating a concrete slab 1 formed with a minor crack 2 and a construction joint 3 several millimetres wide. Both the crack 2 and the construction joint 3 provide points of entry for termites and/or moisture.
[0035] The crack can be sealed by applying the composition with a brush, roller or spray gun to form a continuous barrier at least 2 mm thick and several mm wide to form a flexible, durable barrier to moisture and insects. The composition can also be applied with a spatula or similar tool to force material into the crack and form an even more efficacious barrier.
[0036] However a construction joint cannot be sealed in this way and either of the following methods can be used.
[0037] Turning now to FIG. 2 the composition 4 is applied to either side of the construction joint with a brush, roller, spray, spatula or other similar means. A piece of construction fabric 5 is first coated with the composition on one side, is then applied across the construction joint, coated side towards the concrete. A second coat is then applied across the fabric and the concrete so as to form a continuous waterproof, insect-proof barrier. It will be realised the drawings are illustrations only of the invention and thickness have been exaggerated for illustration purposes.
[0038] Alternatively the construction fabric can be pre-coated and cured and applied to the construction joint after the initial application of the composition to the concrete as described above. In this case, the barrier is completed by applying a second coat of the composition to the membrane after placing the prepared material across the construction joint, paying further attention to the edges of the membrane.
[0039] A further refinement of the technique is shown in FIG. 3 . This is applicable to sealing wall cavities and the like. The membrane 6 is prepared with the cured coating of the composition in a continuous roll with one or both edges 7 left uncoated. The pre-coated material can be cut to length as required, with the untreated edge of edges facilitating sealing the membrane to the concrete slab or to other construction material.
[0040] The invention when formed into a membrane by coating a construction material such as construction fabric whether pre-formed or formed in-situ can be described as a fibre-reinforced membrane. Thus the strength of the construction fabric is greatly enhanced by the fibres in the composition applied to the fabric.
[0041] Further examples of the application of the invention will now be described. The method of applying the membrane is as described above. The preferred form of the membrane is a pre-coated strip with one or both edges left untreated.
[0042] In FIG. 4 the invention is applied to a brick veneer building on a monoslab foundation 9 having a stepped portion 10 . The membrane 8 is positioned between one course of bricks 11 and between the bottom member 12 of the internal wall of the building. The membrane is rolled out, cut to length and sealed to the adjacent bricks and the concrete slab.
[0043] A further building construction is shown in FIG. 5 . The building is a full brick construction having outer wall 13 and inner wall 14 . The foundation is of in-fill construction with a perimeter foundation 15 supporting the outer wall 13 and an in-fill wall 16 . The concrete flow slab 17 of the building is supported on the in-fill wall portion 16 . The membrane 8 is positioned between a course of bricks in the outer wall 13 and between the lowest course of the bricks of the inner wall 14 and the floor slab 17 . In addition membranes 8 a and 8 b can be positioned and sealed by applying layer of the composition to the lower portions of the walls 13 and 16 and applying the membranes 8 a and 8 b , the flexibility of the membranes permitting it to be bent and be sealed against the top surface of the foundation 15 . The membrane 8 b extends up to and is also sealed to the lower side portion of the floor slab 17 .
[0044] An alternate treatment of the building of FIG. 5 is shown in FIG. 6 . In this instance the membranes 8 a and 8 b are not positioned against the lower surfaces of the walls 8 and 16 , the protection of the building being provided by the membrane 8 bridging between the walls 13 and 14 .
[0045] FIG. 7 shows the application of the membrane 8 to extend between a course of bricks in the outer wall 18 to the top surface of a footing slab 19 beneath the inner wall 20 . The footing slab rests on the perimeter foundation 20 .
[0046] Extra protection to the building can be provided as shown in FIG. 8 by the application of membranes 8 c and 8 d . Membrane 8 c seals between the outer wall 18 and the foundation 20 , while membrane 8 d seals between the foundation 20 and the footing slab 19 .
[0047] In an alternate construction the membrane 8 bridging the gap between the outer wall and the inner wall can be omitted, the protection being provided by membranes 8 c and 8 d.
[0048] The composition has many other applications in building construction and other areas.
[0049] Timber treatment, including posts and poles. In this application the composition can be applied direct to the timber as a waterproof, insect-proof coating or can be applied in conjunction with a fabric “sock” in the case of posts and poles to form a more efficacious system. It can be applied to bridging timbers especially abutment timbers. The composition can be used as a waterproof and termite resisting paste or glue for other construction materials, including stainless steel mesh, stainless steel sheeting, and light aluminium.
[0050] The composition can be used as a waterproofing material for general construction, to repair material breaches in damp courses and physical termite barriers, and as a waterproofing sealant in marine applications, for concrete, galvanised metal and other water holding tanks.
[0051] Thus there is provided according to the invention a composition which provides a waterproof and insect and vermin proof barrier. Although the composition can include a termiticide, as an alternative additive the barrier is provided without any such additive. The composition is self curing, and when applied to a material such as construction fabric forms a strong flexible membrane. The composition is self adhering to all surfaces and thus to seal the membrane to a surface, the composition itself can be used without the necessity of a separate adhesive. | A waterproof and insect and termite resistant composition comprising inorganic additives and polyester fibres dispersed in a curable and settable acrylate latex, whereby the composition when covering a point of entry of terminates to a building forms a termite barrier. The said composition impregnated into a construction fibre matting either formed in situ or preformed and sealed in place with the said composition across points of entry of termites to form a flexible, waterproof and insect and termite resistant barrier. | 4 |
FIELD OF THE INVENTION
[0001] The present invention in general relates to an improved well head system and in particular to an improved mechanism for locking a valve stack atop a well head, on beam members of the well template. The valve stack may be a Blow Out Preventer (BOP) and according to the invention, by virtue of this locking, the effect of bending moment on well head by the BOP and a riser connected to the BOP is substantially prevented. Particularly, the present invention relates to a well head system according to the preamble of claim 1 and to a locking device according to the preamble of claim 7 .
TECHNICAL BACKGROUND OF THE INVENTION
[0002] Well head systems for sub sea exploration are traditionally known to comprise a well head having a well head housing secured to a well casing. It also comprises a valve stack, such as a Blow Out Preventer (hereinafter referred to as BOP), located atop a well head during drilling, work-over operations and some phases of the production. Especially, during drilling operations, the drill bit often penetrates pockets of pressurized formations. Due to this, the well bore experiences rapid increase in pressure and unless prevented may result in disastrous blow outs. Hence locating BOPs atop well heads is now very common and indispensable in sub sea exploration.
[0003] Now, tubular members such as risers are connected on the top of the well head housing along the through bore of a BOP. The well head housing is in turn secured to the well head casing by welding. When a riser is connected and operated on the top of the well head housing, it creates a very high bending moment on the connecting surface of the lower part of the well head housing and the upper part of the casing, i.e. at the welded joint area. As a result, the well head and casing experiences strain causing substantial fatigue and may eventually initiate cracks on the well head, thereby expediting its deterioration.
[0004] In a sub-sea drilling operation the connection of the well head housing and well head casing has to endure stress for 5000 days of the BOP and riser being connected, e.g. during work-over operation and this fairly indicates the amount of strain the well head has to withstand due to bending moment generated during riser operation with a safety factor of 10.
[0005] Now to ensure that the well head does not undergo fatigue and tear by bending moment generated during riser operation, it is essential that the BOP should be firmly locked so that less moment is transferred to the weld zone between the well head housing and the casing. This is also essential to ensure that there is no risk of blow out by virtue of a break in the weld between the well head housing and the casing.
[0006] Attempts are on over the years to appropriately secure BOPs on well heads to prevent well blow outs, but in prior art technology the approach to ensure firm locking of the BOP on the well head components, with a motive to substantially is prevent the effect of bending moment on the lower part of the well head housing and the upper part of the casing during operation of tubular members such as risers, along BOP, is missing.
[0007] To be precise, the prior art does not teach locking of a BOP firmly on the well head components, such as the well template, to prevent the well head from movement due to bending moment generated during riser operation, so that fatigue of the well head is substantially reduced during riser operation.
[0008] Hence, the issue of withstanding heavy bending moment on the welded area of the housing-casing joint during riser operation and fatigue of the welded joint area still remains unresolved. This consequently, leaves the problem of minimising/nullifying fatigue of the well head and a potential risk for cracks in the joint area, unresolved. The worst eventuality of this can of course be that the well head disconnects from the casing and results in an uncontrollable blow-out.
[0009] Accordingly there was a long felt need for a locking technology for locking valve stacks, such as BOPs atop a well head on the well template, so that the effect of bending moment on the well head is substantially reduced.
[0010] The present invention meets this long felt need by locking the BOP on beam members of the well template, by providing specially configured locking devices suitably located on axially movable vertical telescopic arms, the arras being positioned along the vertical supporting columns of the BOP.
OBJECTS OF THE INVENTION
[0011] The primary object of the present invention is to provide a well head system which is capable of substantially reducing the effect of bending moment/stress experienced on its welded joint area during riser operation.
[0012] It is yet another object of the invention to provide a BOP atop a well head, which is equipped with a specially configured locking mechanism to substantially prevent the well head from movement due to bending during riser operation through the BOP.
[0013] It is a further object of the present invention to provide a locking mechanism having a plurality of locking devices for locking a BOP on beam members of the well template, so that the effect of high bending moment on the lower part of the well head housing and the upper part of casing is substantially reduced.
[0014] It is a further object of the present invention to minimise/nullify fatigue of the well head and the potential risk for cracks in the well head housing—well casing joint area, during riser operation.
[0015] It is a further object of the present invention to reduce the risk of blow out during riser operation.
[0016] It is yet a further object of the invention to provide a well head system which conforms to the regulatory criteria and safety standard in well drilling processes.
[0017] All through the specification including the claims, the words “BOP”, “riser”, “spindle”, “columns”, “frame”, “beam member”, “clamping arms”, “winching device”, “ROV”, “well template” are to be interpreted in the broadest sense of the respective terms and includes all similar items in the field known by other terms, as may be clear to persons skilled in the art. Restriction/limitation, if any, referred to in the specification, is solely by way of example and understanding the present invention. Furthermore, the description and claim refers to operation of risers and it is hereby clarified that the present invention is equally applicable in respect of operation of other members operated atop sub sea well heads, as will be clear to persons skilled in the art.
SUMMARY OF THE INVENTION
[0018] According to a first aspect of the present invention there is provided a well head system for application in sub sea well exploration. It comprises a well head having a well head housing secured to a well casing and at least one valve stack, e.g. a BOP located atop the well head. According to the invention, the valve stack is removably locked on a well template supporting the well head, by a plurality of locking devices.
[0019] According to a preferred embodiment of the first aspect of the present invention each locking device comprises a spindle fixedly attached to a telescopic arm. It is adapted to axially move downward and upward with corresponding axial movement of the telescopic arms for locking and unlocking respectively.
[0020] Preferably, two opposite clamping arms are adapted to grip a beam of he well template.
[0021] More preferably, the lock comprises a securing mechanism acting to lock a main frame carrying the clamping arms to a spindle.
[0022] According to a second aspect of the present invention there is provided a locking device for securing a valve stack atop a well head having a well head housing secured to a well casing. According to the invention, the locking device is adapted to releasably lock the valve stack to a well template supporting the well head.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Having described the main features of the invention above, a more detailed and non-limiting description of some exemplary embodiments will be given in the following with reference to the drawings, in which
[0024] FIG. 1 is a perspective view of a BOP according to a preferred embodiment of the present invention.
[0025] FIG. 2 is an illustrative view of the telescopic arm of the BOP having a winch device according to a preferred embodiment of the present invention.
[0026] FIG. 3 is a front view of the telescopic arm shown in FIG. 2 .
[0027] FIG. 4 is a sectional view of the telescopic arm shown in FIG. 3 along the line A-A.
[0028] FIG. 5 is a perspective view of the BOP according to the present invention in operation showing the well head components, including a well template, the well head and the location of the locking apparatus.
[0029] FIG. 6 is a perspective view of a preferred embodiment of the locking apparatus according to the present invention in locked position.
[0030] FIG. 7 is an axial cut section along the vertical axis of the device illustrated in FIG. 6 for the sake of understanding.
[0031] FIGS. 8 to 10 coherently illustrate the different positions of the locking apparatus during operation.
DETAILED DESCRIPTION OF THE INVENTION
[0032] The following describes a preferred embodiment of the invention which is exemplary for the sake of understanding the present invention and non-limiting.
[0033] The main aim of the present invention, as stated before, is to substantially reduce the bending moment during riser operation on the lower part of the well head housing (not shown in FIG. 1 ) and the upper part of the casing (not shown in FIG. 1 ), where the welding joint between the two is located. This is achieved primarily by firmly locking the BOP on the well template by specially configured locking devices, at several points along the supporting beams of the well template during riser operations, as hereinafter explained with reference to the drawings. This in turn facilitates reducing the effect of bending moment on the well head during riser operation, thereby increasing its longevity. By reducing the effect of such bending moment, fatigue of the well head and the potential risk for cracks in the well head housing—well casing joint area during riser operation, is substantially minimised/nullified. This in turn also reduces the possibility of most unprecedented eventuality of disconnection of the well head from the casing, resulting in an uncontrollable blow-out.
[0034] FIG. 1 illustrates a BOP assembly 1 including a Christmas tree 6 and room for a BOP stack (not shown) within a BOP frame 2 which is located atop a well head 23 (best shown in FIG. 5 ). It comprises vertical beam members 5 along which are positioned axially movable vertical arms 9 , which are preferably telescopic having one upper portion and a lower portion, the lower portion being slidable through the upper portion. This is clear from FIG. 1 . The locking devices 7 are located along the slidable lower portion of the arms 9 . The BOP 1 rests on the well head 23 (best shown in FIG. 5 ). As known to persons skilled in the art, the christmas tree 6 , at the basal portion atop the well head 23 (shown in FIG. 5 ) may or may not be there. Tubular members such as risers (not shown) are connected to the BOP. The telescopic arms also comprise a suitably located winch device 10 for axial movement of the locking device 7 . As can be seen from FIG. 1 the locking device 7 locks the BOP on horizontal beams 3 , 4 of the well template (best shown as item 15 in FIG. 5 ). These locking devices are effective in firmly locking the BOP along several points on the well template, during riser operation, for achieving the objects of the present invention, as described hereinbefore.
[0035] The axially moving telescopic arms 9 is further illustrated in FIGS. 2 , 3 and 4 , showing one such arm. A winch device 10 is suitably located on the telescopic arm 9 for facilitating its axial movement in upward direction by winching action, as will be understood by persons skilled in the art. The winch has a cable arrangement 11 , as shown in the accompanying FIG. 3 . This arrangement facilitates withdrawal of the lower portion of the telescopic arm in upward direction, along which the locking devices are located.
[0036] FIG. 4 is a sectional view taken along the line A-A in FIG. 3 which preferably shows several handles 13 a, 13 b and 13 c. Each handle is pre-tensioned by a spring 14 and acts against a stop plate 12 on the telescopic arm 9 . The pair of handles 13 a are pulled preferably by an ROV, so that the lower portion of the telescopic arm 9 , having the locking devices, falls downward, thus employing the locking devices 7 .
[0037] It would be clear from the accompanying FIG. 1 , that the locking device 7 is located at the lower portion of the telescopic arm 9 and is lowered on the well head components by downward and axial movement of the telescopic arm 9 . How this movement is caused, has been explained in the concluding portion of the preceding paragraph. This mechanism of employing the locking devices works irrespective of the distance between the well template and the initial position of the arms 9 . The locking devices are also adapted to function irrespective of this distance. The handles 13 c are preferably applied to hold up the lower portion of the telescopic arm 9 , having the locking devices 7 . The handles 13 b are preferably applied, for parking the telescopic arms, when not in use.
[0038] FIG. 5 illustrates four well heads 23 and a BOP on top of one well head. It also shows a well template 15 which supports the well head and along which the locking devices 7 are connected at different points on the well template 15 . As known to persons skilled in the art, the well template rests on the sea bed in deep sea drilling projects, for supporting the well head. The well template 15 is preferably supported on the supporting columns, such as suction anchors 16 . The locking devices are landed on the well template in the manner as stated before which involves a simple and effective operation irrespective of the distance, but landing them correctly, is very crucial. This may be done, for example, from the deck of an offshore vessel.
[0039] The locking device 7 as shown in FIG. 6 comprises a spindle 17 partially housed in a hydraulic cylinder 17 ′, as shown in this figure. It also comprises clamping arms 19 , a main frame 21 , two guard members 20 running from end to end of the clamping arms 19 on either side, hinged levers 18 (only one set shown), operable with either of the clamping arms 19 . The spindle 17 is fixed on a column 22 at the lower end of the telescopic arm 9 , which is movable axially with the axial movement of the corresponding telescopic arm 9 . As shown in FIG. 1 several locking devices 7 are located along several points, near well template 15 . All such locking devices lock the BOP on the well template 15 along several points on the template 15 . Consequently, there is a firm grip which disallows/substantially prevents the BOP from movement due to bending during riser operation. The FIG. 6 shows the locking device in locked position. As stated before, perfect locking is achieved by this technology, irrespective of the distance between the column 22 and the well template 15 .
[0040] The FIG. 7 is an axial cut section along the vertical axis of the device illustrated in FIG. 6 for the sake of understanding. It shows some of the important features by virtue of which, the locking device grips the well template 15 after landing on the same. The spindle 17 is equipped with outer threads 24 .
[0041] An inner wedge portion 26 has inner threads 25 which are adapted to mesh with the threads 24 of the spindle 17 . There also exists outer wedge shaped portion 27 along the outer portion of the inner sleeve 26 . How these portions contribute to effective locking, is explained hereinafter.
[0042] Now the operation of the locking device 7 is explained with reference to FIGS. 8 to 10 . These figures, as can be seen show different operational positions of the locking device and these figures represent an axial cut section along the vertical axis of the device illustrated in FIG. 6 for the sake of understanding.
[0043] FIG. 8 shows a position when the locking device is yet to be locked on the template 15 . This figure also clearly shows the different chambers in the hydraulic cylinder 17 ′ and how the spindle 17 is attached to the column 22 . Ideally, the spindle 17 is attached via a spherical ball bearing 22 ′. This allows the spindle to move and allow for taking up any misalignments. The other identical reference numerals represent identical features as in FIG. 7 .
[0044] FIG. 9 shows a position where the column 22 has come down and landed the locking device 7 on the template beam 15 . The abutment against the template beam presses the supporting frame 21 upwards. Thereby, the hinged levers 18 act to swing the clamping arms 19 downwards so that they come to rest against the template beams and grips around these. The hydraulic cylinder is powered by hydraulic pressure from a hydraulic fluid. As can be seen from the FIGS. 8 to 10 the cylinder has a bottom chamber 32 and an upper chamber 33 . In the hydraulic cylinder 17 ′ there is also a piston 30 , which is pre-tensioned in the downward direction by a spring 31 . A hydraulic pressure in the upper chamber of the hydraulic cylinder 17 ′ acts against the spring 31 , so that the piston 30 is in its uppermost position when the clamping arms are being actuated for gripping.
[0045] The hinged levers 18 actually act as leaf springs and those act to force the clamping arms 19 inwardly when the distance between the main frame 21 and the column 22 is reduced due to the main frame 21 pressing down on the beam 3 , 4 and thereby being pushed upward. The leaf spring 18 may have one arm only and having at least two arms is not mandatory.
[0046] In FIG. 10 the clamping arms 19 have now closed by means of the hinged levers 18 and the grip on the template 15 is completed. As stated in the preceding paragraph, the hinged levers 18 play the role of leaf springs to force the clamping arms 19 inwardly. The guard member 20 ensures that the gripper assumes the correct position on the template beam. When the clamping arms 19 have clamped the beam 3 , 4 of the template 15 , the hydraulic pressure in the hydraulic cylinder 17 ′ is released and the spring 31 actuates the lock by pushing the piston downward. The piston presses against the outer wedges 27 via pins 34 and thereby forces the outer wedges downward. The outer wedges 27 press radially against and forces the inner wedges 26 inward until their inner threads 25 mesh with the outer threads of the spindle 17 . The inner and outer wedges thereby fixes the spindle 17 relative to the main frame 21 , preventing the main frame 21 from moving. Thereby the spring action from the levers 18 maintains their force on the clamping arms 19 and prevents these from swinging upwards again.
[0047] Similar locking takes place along all points on the beam where respective locking devices are located and so, a firm locking of the BOP on beam 15 supporting the well head is achieved. This ensures substantial prevention of the well head from movement due to bending during riser operation with the BOP, thereby reducing the fatigue and risk of failure of the well head and increasing its lifespan.
[0048] As explained in the preceding paragraphs, the securing of the lock is largely effected by the hydraulic cylinder 17 ′, the spring member 31 , the piston 30 , the inner and outer wedges 26 , 27 and the spindle 17 . The details of the spring member and the piston arrangement have not be illustrated in detail in the drawings, but a person of skill will have no problem understanding how this works in principle. It should be understood to persons skilled in the art, particularly with reference to the description of FIGS. 8 , 9 and 10 that securing of the gripping of the well template 15 by the clamping arms 19 take place by a spindle-cam mechanism. This spindle cam mechanism involves mutual operation of the spindle 17 , the spring member and the piston arrangement of the hydraulic cylinder 17 ′, the spring leaves 18 and the clamping arms 19 . All these coherently facilitate, clamping the BOP 1 firmly on the template 15 by the locking devices 7 . During unlocking of the BOP, the hydraulic pressure is applied to the hydraulic cylinder 17 ′ opposite to the spring member and the locking devices just operate in the opposite way as will be understood to persons skilled in the art.
[0049] The present invention has been described with reference to some preferred embodiments and some drawings for the sake of understanding only and it should be clear to persons skilled in the art that the present invention includes all legitimate >modifications within the ambit of what has been described hereinbefore and claimed in the appended claims. | A well head system for application in sub sea well exploration comprising a well head ( 23 ) having a well head housing secured to a well casing, at least one valve stack, e.g. a BOP ( 1 ) located atop said well head ( 23 ). The valve stack is removably locked on a well template ( 15 ) supporting said well head by a plurality of locking devices ( 7 ). Also described is a locking device comprising two opposite clamping arms ( 19 ) hingedly attached to a main frame ( 21 ). The Main frame is slidable relative to a spindle ( 17 ) and can be selectively secured to the spindle ( 17 ). | 4 |
PRIORITY CLAIM
[0001] This application is a continuation of U.S. patent application Ser. No. 13/744,241 filed Jan. 17, 2013 which is a divisional of U.S. patent application Ser. No. 13/036,239 filed Feb. 28, 2011 which is a continuation of U.S. patent application Ser. No. 11/933,949 filed Nov. 1, 2007 which claims the benefit of U.S. Provisional Application Ser. No. 60/916,927 filed on May 9, 2007, and U.S. Provisional Application Ser. No. 61/308,808 filed on Feb. 26, 2010, which applications are herein incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] This invention related generally to structured building materials and, more specifically, to cellular building blocks configured to connect in a multi-dimensional pattern to produce an improved structured building material exhibiting beneficial characteristics.
BACKGROUND OF THE INVENTION
[0003] Wood is a preferred material for building structures because it has high strength, low density and it may be sawed, cut and/or have a nail driven into it. However, in some areas, there is a limited supply of wood to use as a building material. There currently exists a need for a replacement for wood but that has similar characteristics to wood. Finally, it could be manufactured using local materials, without trees and with minimal expense. Artificially mimicking wood's cell structure may provide a variety of benefits such as:
Building a large structure made of smaller, easy to transport parts Imparting redundancy, survivability, and reliability to a material that may suffer damage, including earthquake resistance Using a robotic assembler to build large structures using standard small interconnected cells Mitigating deforestation
SUMMARY OF THE INVENTION
[0008] A cellular building block that connects in a two dimensional or three dimensional pattern to produce a structured material that holds itself together. The cellular building block may be made of many base materials, sizes, and geometrical variations that result in various applications.
[0009] In one embodiment a cell uses a variety of different types of materials made separately into cells and connected mechanically using different geometries. These geometries include, but are not limited to, rectangular and hexagonal geometries, which provide cohesion and strength based on the geometry of the composition. The different geometries combine materials at a cellular level to produce advantageous characteristics in the resulting composition. The advantageous properties include, but are not limited to, low density, strength, toughness, and/or fire resistance.
[0010] A cellular building block made of various materials depending on the application. The cells may be two dimensional (2D) defined as cells which connect together to produce a two dimensional structure of some height and width, but preferably are only as deep as the depth of the cell itself. The cells may be three dimensional (3D), consisting of a pair of 2D cells at right angles, and defined as connecting together to produce a three dimensional structure of some height, width, and depth, for example, hexagonal in design. A group of connected 2D cells is defined as an array. A group of connected 3D cells is defined as a lattice. Arrays or lattices of cells may form a structure such as a beam that holds itself together even at the edges.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Preferred and alternative examples of the present invention are described in detail below with reference to the following drawings:
[0012] FIG. 1 shows a two-dimensional top view of one embodiment;
[0013] FIG. 2 is a top view showing the basic connection of three cells in a two-dimensional arrangement;
[0014] FIGS. 3A-3D show multiple connection methods of cells in a two-dimensional arrangement;
[0015] FIGS. 4A-4E show multiple embodiments of cell end pieces;
[0016] FIGS. 5A-5B show cells connected vertically and horizontally in one embodiment;
[0017] FIGS. 6A-6B show cells connected vertically and horizontally with end pieces attached in one embodiment;
[0018] FIG. 7 shows a sample of the force applied to a series of connected cells;
[0019] FIGS. 8A-8C shows the middle beam intersection of four three dimensional cells;
[0020] FIG. 9A shows a 2D cell that has top/bottom and left/right symmetry. The cell uses the locking barb snap together connection mechanism,
[0021] FIG. 9B shows an idealized 2D cell with top/bottom and left/right symmetry,
[0022] FIG. 9C shows an array of 2D cells depicted in FIG. 9B ,
[0023] FIG. 10A shows a 2D cell that has left/right symmetry, but does not have top/bottom symmetry. This is called polarized because cells are connected in one direction,
[0024] FIG. 10B shows a polarized 2D cell that uses the saw tooth connection mechanism,
[0025] FIG. 11A shows a polarized 3D cell,
[0026] FIG. 11B shows a lattice of 3D cells,
[0027] FIG. 11C shows a lattice of 3D cells with end pieces making the surface smoother,
[0028] FIGS. 12A and 12B show the bottom and top 2D parts of a 3D cell. The two parts may be welded together,
[0029] FIGS. 13A and 13B show pictures of a 3D cell and lattice made from aluminum. Sheet aluminum was water jet cut to produce the 2D cell parts,
[0030] FIG. 14A show 2D cells connected to form an arch. The load on an arch keeps all cell intersections in compression,
[0031] FIG. 14B show 2D cells connected to form an arch close up. Spacers can be inserted to form the arch shape or slightly curved 2D cells could be made,
[0032] FIGS. 15A , 15 B, and 15 C shows a 3D cell, the beginning layer of a lattice, and a lattice that can be used for structures requiring strength against twisting, or can be used to produce a geodesic dome if spacers or slightly curved cells are used,
[0033] FIG. 15D shows a spacer that can be inserted at the intersection points of a hex lattice to make a spherical shape such as part of a geodesic dome,
[0034] FIG. 16A shows a conceptual 2D cell made of a molecule. The possibility of a 3D cell is also hypothesized,
[0035] FIG. 16B shows an array of the 2D molecular cells. The molecule is not identified but its properties are that it consists of tightly bound atoms with a net neutral charge,
[0036] FIGS. 17A and 17B show a 2D cell and array where the cells are made in a mold. This applicable to concrete or ceramics implementations,
[0037] FIG. 17C shows a connection method for molded concrete cells,
[0038] FIG. 17D shows how to reinforce a molded concrete cell. Reinforcement is preferably placed where tension forces are applied,
[0039] FIGS. 18A and 18B show a 2D cell and array made of extruded material. The sliding connection method is used,
[0040] FIGS. 19A , 19 B and 19 C show how a 3D structure could be made by separating the manufacture of the middle cell bars and the cell legs. These cells could be stacked and gravity used to keep the structure connected,
[0041] FIGS. 20A through 20D show cells made to connect using the twist together mechanism. In this embodiment, the center bars of adjacent cells do not need to touch because another set of inside legs are added to keep the cells apart. Each 2D cell, FIG. 20A , preferably has an upper half with two double legs and a lower half with two single legs. The single leg half of one cell twists to hold together the double leg halves of two cells. Connecting must proceed from lower layers to upper layers,
[0042] FIG. 21 shows a bridge built with 3D cells. The bridge could be assembled by one person and without the use of a crane. The height and width of the sides of the bridge can easily be varied to produce the required strength. The road bed is made of cells extended from the sides,
[0043] FIG. 22 shows a toy cell. It would be made of plastic, possibly molded or by using vacuum forming,
[0044] FIG. 23 shows a fence made using pre-cast concrete cells. The cells have steel wire or bar reinforcing rods for tensile strength. The fence could simply use gravity and friction to hold the cells together. If the through hole connecting mechanism was used, the fence could span a gully or a stream,
[0045] FIG. 24 shows 3D cell lattices used as roof beams of a large building such as a convention center. The roof beams are open celled and would allow light to filter through them,
[0046] FIG. 25 shows legs of adjoining cells set in a sprung and un-sprung configuration. This connection method is used for intentional compressing of an array or lattice of cells,
[0047] FIGS. 26A , 26 B, and 26 C show a plastic molded cell, a structure made out of the plastic cells, and a plastic cell array that can be used to validate finite element models of cell arrays,
[0048] FIGS. 27A and 27B show a steel cell made using the electro deposit machining process, and an array of four steel cells connected,
[0049] FIG. 28 shows a cell made using precast cement mix poured into a mold, and
[0050] FIGS. 29A through 29E show a silicon cell made using MEMS technology.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0051] In one embodiment a cell uses a variety of different types of materials made separately into cells and connected mechanically using different geometries. These geometries include, but are not limited to, rectangular and prismatic geometries, which provide cohesion and strength based on the geometry of the composition. The different geometries combine materials at a cellular level to produce advantageous characteristics in the resulting composition. The advantageous properties include, but are not limited to, low density, strength, toughness, and/or fire resistance.
[0052] FIG. 1 shows a two-dimensional top view of one embodiment. The cell has a middle beam 10 . The middle beam has a width, a length and a depth. The cell has two legs 12 , each leg connected along the width (X axis) of the middle beam. Each leg has a length and a width. At each end of the legs is a guide 15 . The guide allows for easy connection with another cell. The leg has a barb 35 located on the inside of the leg. The barb is configured to securely lock in the recess 30 . The cell is composed of, but not limited to, at least one of ceramics, metals, concrete, stone, clay and plastic. These cells are made with a machine or manually by a human in the manual process. In one embodiment the cells range from 1 mm to 10 cm.
[0053] FIG. 1 further shows the important dimensions of a cell. The width of the cell W is measured along the cells X axis. The height of the cell H is measured along the cell's Y axis. The gap between cell middle beam intersections is represented by D. The width of each leg is represented by V. The depth of the middle beam, M, is measured along the cell's z axis. Finally, U is the width of the middle beam and is measured along its Y axis.
[0054] The following dimensions are derived in one embodiment. The depth of each barb A is derived from the width of each leg V divided by four. The length of each barb B is derived from the depth of the barb multiplied by eight. The distance between the legs P is derived from the basic width of the cell divided by two. The distance between the center lines of the legs Q is derived from the distance between the legs P added to the width of a leg V. The distance between outside lines of the legs R is derived from the distance between the center lines of the legs Q added to the width of the leg V. The length of a leg G is derived from the width of the middle beam U subtracted from the height of the cell H and then divided by two. The resulting number is then multiplied by 0.95 to find the length of the leg. The length of the middle beam S is derived from the gap between adjacent cell middle beams D subtracted from the basic width of the cell W. The distance from the outside of the leg to the middle beam intersection N is derived from the distance between the outside lines of the legs R subtracted from the basic width of the cell W and then divided by two.
[0055] In one embodiment, it is preferred, but not necessary, to have the following relationships. The depth of each barb is less than or equal to the width of each leg divided by two. The length of each barb is greater than two times the depth of the barb. The depth of the barb is two times the gap between adjacent cell middle beam intersections. The length of a leg is less than the width of the middle beam subtracted from the basic height of the cell and then divided by two. In a three-dimensional cell, the depth of the middle beam is less than the distance from the outside of the leg to the middle beam intersection. Further the depth of the barb is also constrained by the elasticity of the material and the length of the leg in one embodiment. As a cell is coupled to another, the legs will bend slightly to overcome the depth of the barb until the barb reaches the recess.
[0056] In an alternate embodiment the barbs are removed from one end and recesses are removed from the other end resulting in a cell that is polarized. The cell would have a positive and negative side, and as long as the cells were organized with the correct polarization would form a lattice. In yet another alternate embodiment the cells may be connected without barbs or recesses using rivets, pins and/or screws.
[0057] FIG. 2 is a top view showing the basic connection of three cells in a two-dimensional arrangement. As shown two-dimensional cells are connected together to form an array. The cells in two dimensions are designed such that if the two-dimensional array is subject to bending forces then the bending is distributed among all cell structures. Further damage or a crack to one cell will not propagate to others.
[0058] FIGS. 3A-3D show multiple connection methods of cells in a two-dimensional arrangement. FIG. 3A shows a cell with bidirectional barbs 50 , also shown in FIG. 1 . The barbs shown are symmetrical. FIG. 3B shows a cell with polarized barbs. One side as protruding barbs 52 , wherein the other side has a matching indent 54 . The cells in this arrangement connect in one direction. FIG. 3C shows a cell with a polarized and removable connection 56 . If the cell is connected horizontally and in this configuration the cell would have a spring constantly dependent on the shape and depth of the protrusions and indents. FIG. 3D shows cells preferably connected by a fastener 58 , such as screw, rivet, or push pin through a hole.
[0059] FIGS. 4A-4E show multiple embodiments of cell end pieces. In one embodiment cells may be modified to be end pieces. As a result a block of cells will preferably have a smoother surface.
[0060] FIGS. 5A-5B show cells connected vertically and horizontally in one embodiment. FIG. 5A shows cells connected vertically. When connected vertically compression and tension forces are evenly distributed. In this case there is a low shear stress put on the vertical cell leg connections. FIG. 5B shows cells connected horizontally. In this case more shear stress is put on the cell leg connections; however, there are many advantages to this arrangement.
[0061] FIGS. 6A-6B show cells connected vertically and horizontally with end pieces attached in one embodiment. FIG. 6A shows cells connected vertically with end pieces attached to provide a generally smooth surface. FIG. 6B shows cells connected horizontally with end pieces attached to provide a generally smooth surface.
[0062] FIG. 7 shows a sample of the force applied to a series of connected cells. In one embodiment compression and tension forces are distributed evenly when force is applied.
[0063] FIGS. 8A-8C shows the middle beam intersection of four three-dimensional cells in a lattice. The gap between the middle beam intersections D is represented both along the X and the Z axis. The depth of the middle beam is represented by M. FIG. 8C shows a top view of four three-dimensional cells, the legs are grey in this top view.
[0064] There are several cell connection mechanisms. One connection mechanism shown in FIGS. 9A , 9 B and 9 C is the locking barbs for quick snap together connecting. The legs bend slightly when the cells are joined and then hold together tightly.
[0065] Another mechanism is the use of teeth as shown in FIGS. 10A-10B . This has the advantage of holding together at any point in the joining It also has many points of contact for a strong connection.
[0066] Another connection mechanism is the slide together mechanism as shown in FIGS. 9C and 18B . This is applicable preferably to 2D cells that have been manufactured by extrusion processes. The cells are joined by sliding sideways together.
[0067] Another connection mechanism is the twist together mechanism. A 3D cell can connect to four other 3D cells by positioning the cell legs close to the final position and twisting into place.
[0068] Another connection mechanism is side holes. A hole can be drilled through the two joined legs where a peg may be inserted. When using a mold to manufacture the cell, tubes may be inserted such that there will be holes in the legs of the resulting cell. See, for example, FIG. 3D .
[0069] Another connection mechanism is front half holes. This is where the inside of the legs have a half circle groove such that when the two legs are joined, a dowel or peg may be inserted to prevent the cell connection from coming apart. See FIG. 17C .
[0070] Another connection mechanism is the spring mechanism. It is similar to the locking barbs except the angles are shallow and allow movement after the cells are connected. Because of the outward spring nature of the legs, pushing or pulling on the cells imparts a spring force. See FIG. 25 .
[0071] Another connection mechanism is friction coupled with gravity. In the case of concrete molded cells, they can be stacked upon each other and held in place by gravity. If the leg surface is rough, then friction is often times sufficient to hold the cells together.
[0072] Another connection mechanism is filling the open cell volume with a foam material after the cells have been formed into a lattice. This method provides advantages in holding together ceramic cells.
[0073] There are various solutions to the geometry of 3D cell intersections. This is where the ends of the legs of cells come together when 3D cells are connected into a lattice. One solution is the leg shortening solution. This is where cells in one direction have their legs shortened so they do not overlap the legs in the other direction. FIGS. 8B , 8 C, 11 A, 11 B, 11 C, 12 A, 12 B, 13 A, and 13 B, all show this solution being implemented. Another solution is the 90 degree solution. This is where the ends of the legs are cut to 90 degree points so that all four legs come together. See FIGS. 19A and 19C .
[0074] In the case of hex cells, three hex cell legs come together. One solution for this situation is where the ends of the legs are cut to 120 degree angles. See FIGS. 15A , 15 B, and 15 C.
[0075] There are a variety of materials that may be used for a cell. For example, nano-scale molecules may be used to construct a cell. FIGS. 16A and 16B show an exemplary arrangement of molecules wherein no particular molecule is identified. The cell molecule would have very strong bonds with its own atoms but could be charge neutral with other cells. In this embodiment, the geometry is the principal means to hold them together rather than a chemical bond.
[0076] For concrete and ceramics, cells are preferably moldable. In this embodiment, cells have rounded corners and beveled legs for mold release. Concrete cells preferably incorporate reinforcing rods or bars for stress points and places where tensile strength is required. Ceramic cells have the potential to have much higher tensile strength (psi) as the size of the cell decreases. The material is also inexpensive, so ceramic cells could result in lightweight and strong bulk material that has low density and toughness at low cost.
[0077] A variety of materials may be used in the present invention, each exhibiting different characteristics. Wood is aesthetically attractive. A steel plate attached to the wood cell provides it the proper tensile strength in all directions. Aluminum is a good material for most cell geometries including extrusion. Plastic is a good material for most cell geometries. Injection molding is typically the least expensive method to produce cells. Vacuum forming is ideal for large play toys.
[0078] Carbon composites can be used to make cells. Care must be taken to analyze the stress points and tensile strength used in the application. This material has the potential to make very large beams that are very light and strong. The advantage of using cells is that the resulting beam is toughened. In the event of failure or damage to cells, the beam remains intact. Manufacturing many small composite parts may be much less expensive than few larger parts.
[0079] There are many applications of the invention. The following are provided as non-limiting examples.
[0080] Beams and bridges are an important application. The arrangement of cells can be optimized to minimize the material and maximize the strength where it is required. Using arches put the cells in compression where they can be very strong. A bridge or beam may be constructed without large cranes because an initial starting beam is constructed and then cells added until the desired strength is obtained. The structure is also resistant to corroded or damaged cells because of the massive redundancy of cells. See, e.g., FIGS. 21 and 24 .
[0081] Geodesic domes may be made from the hex cells. With a slightly larger leg size in outer shells, the cells will naturally produce a dome and will come together as parts of a geodesic. FIG. 15D shows an example of a spacer. In a multi-layer implementation, an outer layer preferably has larger spacers than the next inner layer. If the radiuses of the inner and outer layers are not too much different, then the spacers can have an Extend dimension that is small. This allows the use of one standard cell for all layers as long as the connecting legs have the required flexibility.
[0082] Large size cells that are easy to connect and disconnect may be used for scaffolding.
[0083] Mattresses or cushions may be made out of a lattice of cells that use the spring connection method.
[0084] Airless tires may be made of arch shaped cells connected using the spring connection method.
[0085] Construction toy kits or sets make forts and shapes.
[0086] Fences may be made that would be easy to assemble, having a long life cycle, and have the strength to span gullies above the ground. 3D versions may be used as a bulwark where fill dirt can be dumped into the open cells.
[0087] Hedges and arbors may be constructed that can have plants growing within the open cell structure.
[0088] Outer space structures are another application. Cell parts may be efficiently packed in a small space for lifting into orbit. Easily connectable and disconnectable cells may be used to make large 3D structures.
[0089] Aircraft parts may be made out of carbon composite cells.
[0090] A robotic mechanism could be created that when fed cells from a cartridge would travel and climb to form a building. If the robot could also disconnect cells already installed, then the robot could create its own scaffolding as required. More cells producing thick walls may be used in the foundation and lower floors of a building and taper off as the building gets higher. Cranes would not be required for building construction.
[0091] There are many manufacturing methods that depend on the material being used. For example, cells can be manufactured using extrusion, water jet cutting, injection molding, with precast concrete molding methods, with milling machines, and with die cast molds.
[0092] Another manufacturing method that can be employed is one used to produce MEMS (Microelectromechanical Systems) devices. FIGS. 29A through 29E show an example using silicon as the material and the DRIE (Deep Reactive Ion Etching) manufacturing method. The parts shown in FIGS. 29A and 29B are welded together at 90 degrees to create a 3D cell, FIG. 29C . Welding can be done with silicon by heating the joint, for example, with a laser. The cells preferably use the leg shortening intersection method. A fine grained lattice of cells may be produced. Possible applications are as a structural material or as scaffolding for mounting other MEMS parts.
[0093] FIG. 29E shows a close up of one axis of a silicon cell connection. Simple guidelines are preferably used to help determine the dimensions of the guide, barb, and recess used in the connection. See, for example, FIG. 1 showing the guide 15 , barb 35 , and recess 30 . For the silicon cell, the guide is preferably a rounded edge, the barb is a half circle protrusion, and the recess is a half circle indent. One 3D cell is positioned above four lower cells at an intersection and pushed into place. Assuming the arms of the cell are simple rectangular cross sections and the center bar is being held in place, the force required to bend the arm at a point of distance L above the bar is dependent on E, the Young's Modulus of the material, the width V of the leg, the depth W of the leg, and the distance D of the leg has been displaced. As an approximation, assume the angle of bending is small, tan(theta)˜=theta. The force is E*V*W*D*(V/L)̂2/(12*L). For silicon, E˜=100 GPa. The largest displacement that is allowed is dependent on the maximum yield stress of the material, which is about 5000 MPa for silicon. Dmax-silicon is 2*5000e6*LA2/(E*V). For the silicon cell, the insertion force worst case is bending the end of the leg at the guide a distance D and doing that for all four legs. This assumes the protrusion touches at a 45 degree angle to the guide. F=1.0e11*1e-4*5e-4*25e-6*(1e-4/1e-3)̂2/(12*1e-3)=0.104 Newtons per Leg (about 10.6 grams force/leg).
[0094] While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow. | An improved cellular building block including a middle beam and two legs. The cellular building block having the first leg coupled to the middle beam such that the leg is perpendicular to the middle beam and a second leg coupled to the middle beam such that the leg is perpendicular to the middle beam and spaced apart from the first leg, the first leg and the second leg having an inside edge and an outside edge. Having at least one barb located on the inside edge of the first leg and on the inside edge of the second leg and further configured to lock into a recess. The cellular building blocks connect in a two dimensional or three dimensional pattern and a produce a structured material that holds itself together and exhibits beneficial characteristics. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention relates to a puncture method and a puncture system. More specifically, the present invention relates to a novel modification thereof to carry out the aspiration of a sample from an organ and the examination of the inner conditions of the organ without the outward leak of the fluid and the like in the organ of human bodies and animals.
2. Description of the Prior Art
A puncture method generally comprising puncturing a site to be punctured in an organ with an injection needle and aspirating the inner fluid and the like for pathological examination of the fluid and the like, has been employed conventionally.
Because the conventional puncture method has been conducted as described above, the following problems have been remarked.
When an injection needle is inserted into a site to be punctured to aspirate and then withdraw the fluid and the like, an opening remains at the site punctured so that the fluid and the like may leak into bodies, eventually causing the metastasis of the fluid into other organs if the fluid is malignant.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a puncture method and a puncture system for aspirating a sample from an organ and examining the inner conditions of the organ without leaking fluid and the like from the organ of human bodies and animals.
In accordance with the present invention, a medical instrument for use in puncturing an organ of interest within a body cavity is disclosed having a first tubular body with a first end for being inserted into a body cavity and a second end. The first tubular body has a severable portion proximate the first end. A seal is provided within the severable portion. A resilient parasol with a normally opened and a closed position extends from the first end, as well. A second tubular body contains the first tubular body and parasol, compressing the parasol and maintaining the parasol in the closed condition when the parasol is within the second tubular body. When the parasol is advanced out of the second tubular body, the parasol deploys into its normally opened condition. The severable portion is preferably defined by a circumferential groove around the tubular body. A reservoir within the first tubular body sealed with a removable plug, or a cuttable bag which depends from the first end of the tubular body, may be provided for delivering adhesive to between the parasol and the organ of interest.
A system is also disclosed including the medical instrument described above and adhesive for connecting the opened parasol to the organ, a needle for puncturing the organ after the parasol is connected to the organ and cutting means for cutting the severable portion of the first tubular body. A kit of parts is disclosed, as well.
By the puncture method and the puncture system in accordance with the present invention, the puncture system is inserted through an opening formed on the wall of a human body or an animal body to push in only the first tubular body. The parasol part and the reservoir are then sprung out from the second tubular body, whereby the parasol part is opened from the compact folded shape into the original parasol shape. The surface of a site to be punctured is dried by a drying means inserted from another direction and thereafter adhesive is fed by cutting of the bag part, removal of the plug or other adhesive feeding jigs onto the site to be punctured or the parasol part to a final film thickness of about 0.1 to 0.2 mm.
At the state described above, pushing inwardly the whole system, the parasol part gets in close contact with the site to be punctured, so that the two are integrated by means of the action of the adhesive.
Inserting the needle body into the first tubular body then punctures the sealing part and passes through the site to be punctured. Drawing out only the bar-like needle part from the tubular needle part and inserting the aspirator into the head of the tubular needle part for aspiration, the fluid and the like in the site to be punctured can be aspirated and drawn out. Cutting the tubular body immediately after completion of such aspiration, the parasol part and a part of the tubular body remain on the site to be punctured, along with the compaction of the sealing part to recover the original shape, so that the opening made during puncturing with the needle body disappears and the opening formed on the site to be punctured is completely occluded with the sealing part, whereby the outward leak of the inner fluid can be prevented. Thus, the metastasis of a malignant cancer via such leak to other organs can be prevented.
By inserting a camera or a sample collector instead of the aspirator described above, the inside of the site to be punctured can be observed or a biological sample can be collected.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 depicts the sectional view of the principal part of the puncture system in accordance with the present invention;
FIG. 2 depicts the enlarged sectional view of the sealing part of FIG. 1;
FIG. 3 depicts the sectional view showing another example of FIG. 2;
FIG. 4 depicts the sectional view showing still another example of FIG. 2;
FIG. 5 depicts the structurally decomposed view of the system of FIG. 1, for arranging a first tubular body;
FIG. 6 depicts the structural view showing a second tubular body;
FIG. 7 depicts the sectional view showing the tubular needle part of the needle body;
FIG. 8 depicts the sectional view showing the bar-like needle part;
FIG. 9 depicts the sectional view of the needle body;
FIG. 10 depicts the compositional view of a woman's abdomen showing a step in a puncture method for use in the treatment of ovarian cancer, wherein a trocar is being inserted into the abdomen;
FIG. 11 depicts the compositional view of the women's abdomen after insertion of the trocar;
FIG. 12 depicts a next step in the puncture method, wherein the puncture system is inserted into the trocar;
FIG. 13 depicts the longitudinal sectional view of the abdomen after insertion of the puncture system;
FIG. 14 depicts the transverse sectional view of the abdomen after insertion of the puncture system through the trocar;
FIG. 15 depicts the longitudinal sectional view of the abdomen after deployment of the parasol;
FIG. 16 depicts the transverse sectional view of FIG. 15, showing the drying means in phantom;
FIG. 17 depicts the longitudinal sectional view of the abdomen during hooking of the bag part;
FIG. 18 depicts the transverse sectional view of FIG. 17, further illustrating the hooking means;
FIG. 19 depicts the longitudinal sectional view of the abdomen showing the parasol part in adhesion to the site to be punctured;
FIG. 20 depicts the transverse sectional view of FIG. 19;
FIG. 21 depicts the longitudinal sectional view of the abdomen immediately prior to puncturing;
FIG. 22 depicts the transverse sectional view of FIG. 21;
FIG. 23 depicts the longitudinal sectional view of the abdomen, wherein the site of the cancer is punctured;
FIG. 24 depicts the transverse sectional view of FIG. 23;
FIG. 25 depicts the longitudinal sectional view of the abdomen during aspiration;
FIG. 26 depicts the transverse sectional view of FIG. 25;
FIG. 27 depicts the longitudinal sectional view of the abdomen after aspiration when the needle body is removed;
FIG. 28 is a view of a portion of the tubular body prior to cutting;
FIG. 29 depicts the transverse sectional view of the abdomen showing the cutting means;
FIG. 30 depicts the longitudinal sectional view of the abdomen after the puncture system is removed;
FIG. 31 depicts the transverse sectional view of FIG. 30;
FIG. 32 depicts the transverse sectional view of the abdomen showing an embodiment using a camera;
FIG. 33 depicts the transverse sectional view of the abdomen showing an embodiment using a sample collector,
FIG. 34 is a structural view of another embodiment;
FIG. 35 is a sectional view of another embodiment;
FIG. 36 is a sectional view of a further embodiment;
FIG. 37 is a sectional view of a still further embodiment; and
FIG. 38 depicts the sectional view of the abdomen during surgery condition.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The puncture method and puncture system of the present invention will now be explained in detail below with reference to the drawings.
FIG. 1 shows the principal part of the puncture system of the first embodiment; "1" represents a parasol part in a parasol shape composed of urethane rubber; a tubular body 3 containing an adhesive reservoir 2 is integrally formed (may be also formed separately) at the position of the axial center of the parasol part 1; and the reservoir 2 is composed of stopper 1A and sealing part 3A, arranged in a sealing fashion on the tubular body 3. Herein, the tubular body 3, the parasol part 1 and the sealing part 3A may be integrally molded, or they may be composed of separate parts and then integrally connected together. The stopper 1A is composed of rubber and the like, arranged in a removable manner on the tubular body 3. By pulling wire 1Aa connected with the stopper 1A, the stopper 1A can be removed from the tubular body 3. As shown in FIG. 2, the sealing part 3A is composed of first and third films 3Aa and 3Ac arranged at the both ends in the axial direction and second film 3Ab positioned intermediately between them, and a cross-cut 3B is formed on the second film 3Ab so that the needle and the like described below might readily pass through the sealing part 3A. Furthermore, the structure of the sealing part 3A comprises not only such three layers but also a single layer or two layers. Further, there may be provided the sealing part 3A as shown in FIGS. 3 and 4.
On the tubular body 3, there is arranged screw body 5 of a tubular form comprising corrosion-resistant aluminium and the like. Adhesive 7 such as surgical Allon-alfa and the like (other adhesives may be used as well) is injected into the reservoir 2 by means of injector 6, immediately prior to use. Without using the injector 6, adhesive 7 may be fed into the reservoir 2 after removing the stopper 1A. Incidentally, it is preferable to set an amount of this adhesive to 0.1 cc through 2.0 cc.
A tubular body 9 of nearly the same outer diameter as that of the screw body 5, comprising corrosion-resistant aluminium and the like and having also first holder 8, is helically connected in series connection with the screw body 5. Furthermore, the tubular body 9 may be directly or indirectly connected with the tubular body 3, integrally or in a separate fashion.
As shown in FIG. 6, the tubular body 9 connected with the screw body 5 has a second holder 10, and is inserted along the coaxial direction into a second tubular body 11 comprising corrosion-resistant aluminium and the like. Thus, the puncture system 20 in accordance with the present invention is depicted in the state of completion in FIG. 6. In this state, the parasol part 1 is closed into a more compact shape and is contained in the second tubular body 11. As shown in FIG. 1, the parasol body 1 is composed of urethane rubber and the like; and the tubular body 3 is composed of silicone rubber, a resin and the like.
FIGS. 7 to 9 depict the structure of a needle body 30 to be used in the puncture system 20 shown in FIG. 6 described above; FIG. 7 depicts a tubular needle part 31; and FIG. 8 depicts a bar-like needle part 32 to be inserted into the tubular needle part 31. Taper-like insertion part 33 is formed on the rear end of the tubular needle part 31, and by inserting the bar-like needle part 32 through the insertion part 33 into the tubular needle part 31, a guide hole 30a inside the tubular needle part 31 is occluded. By forming a diameter D1 of a expanded part 32a formed on the rear part of the bar-like needle part 32 far larger than the bore diameter of the insertion part 33, the insertion part 33 can be occluded structurally by means of the expanded part 32a. Furthermore, the needle body 30 is entirely coated with silicone coating.
Description of puncturing a human organ or an animal organ by means of the structure described above, follows human ovarian cancer.
As shown in FIGS. 10 to 14, a laparascope 41 is inserted into the wall body 40 for expansion under gas supply, to stand up tubular first trocar 42. As shown in FIGS. 13 and 14, inserting the puncture system 20 of the present invention through the first trocar 42 into the wall of the body 40 to push in only the tubular body 9 as shown in FIG. 15, parasol part 1 is pushed outside from the inside of the second tubular body 11. Then, the parasol part 1 is opened from the compact shape into the original parasol shape.
As shown in FIG. 16, using drying means 44 for supplying dry air or gas through second trocar 43 inserted into the wall body 40 from the other direction, the surface of an ovarian cancer site to be punctured 45, for example, is dried. Subsequently, the drying means 44 is withdrawn from the second trocar 43 and a hooking means 46 is inserted through the second trocar 43 and the wall body 40, for pulling wire 1Aa, as shown in FIGS. 17 and 18. Stopper 1A is removed by the hooking means to supply adhesive 7 onto the site to be punctured 45. Additionally, the adhesive 7 should be injected primarily into the reservoir 2, immediately prior to surgery.
As shown in FIGS. 19 and 20, pushing the puncture system 20 through the wall body 40, the parasol part 1 is fixed through the adhesive 7 onto the surface 45a of the site to be punctured 45. As shown in FIGS. 21 and 22, needle body 30 is then inserted into the puncture system 20. As shown in FIGS. 23 and 24, then, the needle body 30 is passed through sealing part 3A, so that the tip of the needle body 30 can be inserted into the site to be punctured 45.
Drawing only the bar-like part 32 from the tubular needle part 31 while in such state, inserting aspirator 50 into insertion part 33 of the tubular needle part 31 for carrying out aspiration, as shown in FIGS. 25 and 26, the fluid and the like in the site to be punctured 45 are aspirated into the aspirator 50, whereby sampling is completed.
After completion of the aspiration and drawing out the tubular needle part 31, a cutting means 46A composed of a scissor is inserted into the wall body 40, as shown in FIGS. 28 and 29, to cut recessed groove part 3c of the tubular body 3 while the parasol part/is fixed to the site to be punctured 45. Only a part of the tubular body 3 and the parasol part 1 are left fixed to the site to be punctured 45. In such case, the shape of the site to be punctured 45 is in the compact shape compared with the original shape. Furthermore, because the opening left on the sealing part 3A after drawing out the needle body 30 is occluded by means of the shrinking action of the elastic body, the leak of the fluid and the like in the site to be punctured 45 to the outside (namely, endoabdominal region) can be prevented.
Then, it should be determined whether or not the fluid and the like in the site to be punctured 45 is malignant and which operative technique should be adopted. When it is diagnosed that the sample is benign, the site to be punctured 45 should be resected. Concurrently with the resection of the site 45, the remaining parasol part 1 and the like should be removed from the body, as shown in FIGS. 30 and 31. When the fluid and the like are malignant, alternatively, the site to be punctured 45 is resected while being enclosed by a bag (not shown) to prevent the spread of the fluid and the like into the endoabdominal region. Thus, the metastasis of a malignant cancer, if any, to other organs can be prevented. Furthermore, coating the tip of the needle body 30 with silicone coating so as to avoid the adhesion of an adhesive, the needle body 30 is advantageously passed through the sealing part 3A.
In another example, by inserting camera 60 instead of the aspirator 50 into the site to be punctured 45, as shown in FIG. 32, the inside can be examined by means of monitor TV 61 for establishing the diagnosis.
As shown in FIG. 33, furthermore, inserting a well known sample collector 70 instead of the camera 60 and controlling the sample collector 70 by means of a remote controller 71, a biological specimen may be drawn out from the site to be punctured 45.
The above example describes the surgery of a human body. It is needless to say that the above example may be applied also to animals, with no specific limitation to humans. The above example describes the surgery by means of laparascope 41. If such laparascope 41 is not used, however, the system does not require the second tubular body 11 but requires the tubular body 3 and the first tubular body 9, as shown in FIG. 5. The present invention is not limited to the foregoing embodiment, but may be applicable to the following embodiments, as well.
Instead of the reservoir 2 employing the plug 1A in the above-mentioned first embodiment, as shown in FIG. 34 illustrating a second embodiment, an adhesive feeding jig 100 containing the adhesive may be inserted into the peritoneal cavity to feed the adhesive 7 onto the puncture site or the parasol part 1, without use of the reservoir 2 and the plug 1A. In the embodiment of FIG. 34, the sealing part 3A of the tubular body 3 includes a pair of sealing plates 101. Ethyl alcohol can be contained within the region 102 between the sealing plates 101. Further, in a third embodiment illustrated in FIG. 35, a tubular body 4 made of corrosion-resisting aluminum or the like is fitted to an outer periphery of the elastic holder body 3b, so that pressure is applied to the elastic holder body 3b from its outer peripheral side by the tubular body 4 to squeeze and shrink a port 3a formed after the puncture by the needle body or the like for restoration to its original state. A tubular threaded body 5a made of corrosion-resisting aluminum or the like is disposed at the lower end of the elastic holder body. Incidentally, the adhesive, such as surgical Allon-alfa is injected into the bag part 2a, which may be substituted for the reservoir 2, by an injection appliance 6 immediately prior to usage. Accordingly, the bag part 2a is constructed as shown in FIG. 36 and 37. For practical surgery, as shown in FIG. 38, the bag part 2a is broken within the peritoneal cavity by using cutting means 46a to feed the adhesive 7 for bonding the parasol part 1 to the site to be punctured, so that the procedure similar to that of the first embodiment can be performed.
Because the puncture method and puncture system in accordance with the present invention are composed as described above, the following advantages may be brought about.
Because a parasol part adheres through an adhesive to a site to be punctured and a needle body is then inserted through the sealing part, the opening of the sealing part is shrunk and occluded after drawing out the needle body, to prevent the outward leak of the fluid and the like in the site to be punctured.
The insertion of a camera and a sample collector can be done through the needle body, whereby a wide variety of the applications can be achieved in medical fields. | The present invention relates to a puncture method and a puncture system. More specifically, the objective of the present invention is to carry out the aspiration of a sample from a human organ or an animal organ and the inner examination thereof, without the outward leak of the fluid and the like in the organ.
The puncture method and puncture system of the present invention is in the following structure; making a parasol part arranged on a reservoir adhere through an adhesive to the site to be punctured, inserting a needle body through a sealing part of the reservoir into the site to be punctured to draw out the inner fluid, the leak of the fluid can be prevented by the reverse operation of the sealing part. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
This application is related to co-owned application entitled "Novel Way of Introducing Gas into an RTP Chamber", by James Tietz et al., Attorney Docket No. 1043/RTP/LE, filed on an even date herewith, and incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates to chemical vapor deposition systems.
Chemical vapor processes for thin film fabrication pass a vapor over a substrate to either grow a film on the substrate, etch the substrate, or otherwise react with a material on the substrate to change the character of the substrate surface. For example, in a chemical vapor deposition (CVD) process for fabricating semiconductor devices, a flow of a reactive vapor is directed to an exposed side of a disk-shaped semiconductor wafer. The wafer is sometimes supported around the periphery of its bottom side on an annular-shaped ledge of an edge ring. The wafer's peripheral edge is left exposed. The substrate is sometimes rapidly heated to facilitate or speed the vapor processing, for example, in rapid thermal chemical vapor deposition (RTCVD) processes, rapid thermal oxidation processes (RTO), and rapid thermal nitridation (RTN) processes.
In such a system, the reactive gases can spill over the edge of the wafer and edge ring, depositing a non-uniform film on the peripheral edge of the wafer and on its backside. Non-uniform depositions on the edge or backside of the wafer can flake off and thereby generate particles that contaminate the process chamber. Also, non-uniform depositions are undesirable for subsequent wafer processing.
One approach to inhibit the process gases from depositing on the edge or backside is to use an edge ring that covers a portion of the upper surface of the wafer. Another approach is to coat the entire backside uniformly to produce a more stable film less likely to flake. To this end, the wafer is supported on pins so that the process gases can easily deposit on the backside. In those cases where depositing on the backside is undesirable, one or another of a variety of edge-specific purges with inert gases are used to prevent reactive gases from reaching the edge and backside areas. One type of such a system uses a susceptor with built-in channels for directing purge gas flows to the edge of the wafer.
Current schemes for providing effective edge purging may incompletely isolate the backside from reactive gases if the flow of purge gas is too weak. If the purge gas is flowed more strongly, it can spill over the front side of the wafer and mix with the process gas at the periphery of the wafer by diffusion or by convection. The resulting dilution of reactive gases over the front side of the wafer leads to incomplete film deposition near the periphery of the front side, thereby reducing the usable area having a uniform film on the wafer.
SUMMARY OF THE INVENTION
The invention provides a method and apparatus for purging a backside of a substantially disk-shaped substrate, or wafer, during a vapor process. The method includes the steps of spinning the substrate about a central axis, supplying a flow of an inert purge gas through an aperture, or nozzle, to the back side of the spinning substrate, and impelling the flow of purge gas in an outward radial direction with the spinning substrate. The purging can be conducted during a chemical vapor process in which a process gas is flowing onto a front side of the spinning substrate.
According to another feature of the invention, the method includes the step of channeling the radially impelled purge gas through a plurality of apertures that are defined by confronting surfaces of the substrate and an edge ring supporting the substrate. The channeling step can include directing the purge gas in a generally axial direction near a peripheral edge of the substrate.
According to another feature of the invention, the spinning step includes spinning the substrate at a rate of at least approximately 90 rpm.
The apparatus for conducting the backside purge in a chemical vapor processing system includes a support mechanism structured and arranged to support the substrate and spin the substrate about its central axis, and a conduit coupled to a source of purge gas, the conduit being structured and arranged to direct a flow of the purge gas toward the backside of the substrate such that the spinning substrate causes the purge gas to flow radially outward.
According to another feature of the invention, the support mechanism is structured and arranged to spin the substrate at a rotational speed of more than approximately 90 rpm.
The support mechanism includes an edge ring supporting the wafer around its peripheral edge, and a support cylinder supporting the edge ring and coupling it to a rotation apparatus. Other features may be built into either the edge ring or the support cylinder. Such features could include areas for passage of gases outward from the wafer, or ridge or vane structures to impart further momentum to the gas to achieve desired results.
The vapor processing system forms a desired film on the front side of a wafer by flowing reactive gases towards the front and a purge gas to the backside. The wafer and the edge ring are spun about a central axis during the process. Gases impinging on both sides of the wafer are impelled radially outward toward the edge, departing the edge of the wafer at a relatively high flow rate.
The radial flow imparted to both the reactive process and nonreactive purge gases (from the front and back sides of the wafer, respectively) ensures that both gases are swept away from the edge of the wafer with minimal mixing within the circumference of the wafer. Thus, the backside purging is especially effective because the reactants flow away before they can diffuse to the backside. Likewise, the present invention prevents dilution of the reactant on the front of the substrate by the same radial motion of gases, and thereby helps to provide more uniform film profiles, especially near the edge of the wafer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic cross-sectional side view of a vapor processing system that uses rotational backside purging.
FIGS. 2(a) and (b) are partial diagrammatic cross-sectional side views of a substrate and support structure showing gas flow patterns (a) when there is no reaction gas flow and the substrate is not rotated, and (b) when a reaction gas is directed towards the front side of the substrate and the substrate is rotated.
FIGS. 3(a)-(c) schematically illustrate deposition profiles near the peripheral edge of a wafer under different conditions;
FIG. 4 is a cross-sectional side view of an RTP system embodying of the invention;
FIG. 5 is a plan view of an edge ring;
FIG. 6 is a sectional view through lines 6--6 of FIG. 5, with a substrate shown in shadow;
FIG. 7 is a plan view of another embodiment of an edge ring;
FIG. 8 is a sectional view through lines 8--8 of FIG. 7, with a substrate shown in shadow; and
FIG. 9 is another embodiment of a nozzle for introducing the purge gas into the cavity behind the substrate.
In the following detailed description of the invention, the same structures illustrated in different figures are referred to with the same reference numerals.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a vapor processing system that purges a backside of a substrate 10 includes a rotatable support structure 12 mounted in a process chamber 14. A reaction gas supply 16 provides a regulated flow of a reaction gas 18 that is directed through apertures formed in a shower-head type nozzle 20 to a front surface 22 of substrate 10. Gases are removed through exhaust 24, which is coupled to a vacuum pump (not shown). The bottom 28 of chamber 14, the support structure 12, and the backside 26 of substrate 10 together define a cavity. A purge gas supply 30 provides a regulated flow of non-reactive purge gas 32 that is directed through an aperture 34 in the bottom 28 of chamber 14 towards the backside 26 of substrate 10.
When the front and back surfaces 22, 26 rotate, they impart an outward radial momentum to the reaction gas 18 and the purge gas 32, respectively. At sufficiently high rotational speeds, the interaction of the substrate surfaces 22, 26 with the gases 18, 32 causes the gases to flow in an outwardly radial direction toward the peripheral edge 36 of substrate 10.
Referring now also to FIGS. 2(a) and (b), the substrate 10 rests on an inner annular ledge 38 of an edge ring 40. In this embodiment, ledge 38 is flat so that when the substrate 10 is resting on it, the flow of purge gas in a gap 41 that necessarily exists between the backside of the substrate and the annular ledge 38 is significantly restricted. This produces a higher velocity of any purge gas which does manage to flow through region 41 thereby also producing a more effective barrier to process gas flowing back through region 41 into the region behind the wafer.
An upper surface 42 of an outer annular portion 44 of the edge ring 40 is approximately level with the upper surface 22 of the substrate 10. Under some circumstances, it may be undesirable to have an upward step or a downward step that could disturb the smooth outward flow of process and purge gases. Also a downward step could allow process gases to interact more easily with the peripheral edge of the substrate. The interaction of the gases 18 and 32 with the rotating substrate upper surface 22 and outer annular portion upper surface 42 transfers additional outward radial momentum to the gases. Both gases 18 and 32 move radially outward and away from the upper surface 22 of the substrate 10.
The outward radial flow inhibits the significant mixing of the purge gas 32 with the reaction gas 18 over the substrate upper surface 22. This helps to achieve a more uniform process profile out to the periphery of the upper surface 22 of the substrate 10. The flowing purge gas 32 prevents the reaction gas 18 from migrating over the peripheral edge 36 of the substrate, and thereby helps to prevent the reaction gas 18 from depositing an unwanted film on the edge 36 or the back surface 26 of the substrate 10.
A film 46a produced on a wafer substrate 10 without a flow of a purge gas and/or without rotating the wafer 10 is schematically illustrated in FIG. 3(a). The film 46a extends onto the peripheral edge 36 of the wafer 10 and around onto the backside 26. These areas of the film are typically thinner than the film produced on the upper surface 22 of the wafer 10. The film 46a can easily flake off from these regions, thereby contaminating the system with particles.
FIG. 3(b) shows a second film 46b produced by flowing purge gas 32 during the deposition, but without rotating the wafer 10 at speeds sufficient to cause an outward radial flow of the purge gas 32 or process gas 18. In this case, the film 46b has a reduced profile, or thickness, near the edge 36 of the wafer 10, thereby reducing the usable area of the upper surface of the wafer.
FIG. 3(c) schematically illustrates a third film 46c produced by flowing purge gas 32 during the deposition and by rotating the wafer 10 at speeds sufficient to cause an outward radial flow of the purge gas 32 and process gas 18. Film 46c has a more uniform profile near the edge 36 of the wafer 10, and does not extend around the edge 36.
A rapid thermal processing (RTP) system that has been modified in accordance with the invention is shown in FIG. 4. The RTP system includes a processing chamber 114 for processing a silicon wafer 110 (e.g. a 200 mm or 300 mm diameter wafer). The wafer 110 is held inside the chamber on a rotatable substrate support structure 112 and can be heated by a heating element 100 located directly above the substrate.
The heating element 100 generates radiation which enters the processing chamber 114 through a water-cooled quartz window assembly 102 which is approximately one inch (2.5 cm) above the substrate. Beneath substrate 110 is a reflector 104 which is mounted on a water-cooled, stainless steel base 106. Reflector 104 is made of aluminum and has a highly reflective surface coating 108. The backside 126 of wafer 110 and the top of reflector 104 form a reflecting cavity for enhancing the effective thermal emissivity of the wafer 110.
Support structure 112 includes an edge ring 140 which contacts the wafer 110 around the wafer's outer perimeter, thereby exposing all of the backside 126 of the wafer 110 except for a small annular region about the outer perimeter. Edge ring 140 has a radial width of approximately one inch (2.5 cm). To minimize the thermal discontinuities that will occur at the edge of wafer 110 during processing, edge ring 140 is made of the same, or similar, material as the wafer, e.g. silicon or silicon carbide coated with silicon.
Edge ring 140 rests on a rotatable tubular quartz cylinder 156 that is coated with silicon to render it opaque in a frequency range of pyrometers 153 that measure the temperature profile of backside 126. The silicon coating on the quartz cylinder 156 acts as a baffle to block out radiation from external sources that might contaminate the measurements. The bottom of the quartz cylinder 156 is held by an annular upper bearing race 158 which rests on a plurality of ball bearings 160 that are, in turn, held within a stationary, annular, lower bearing race 162. The ball bearings 160 are made of steel and coated with silicon nitride (or alternatively, solid silicon nitride) to reduce particulate formation during operation. Upper bearing race 158 is magnetically-coupled to an actuator (not shown) positioned on the outside of the chamber, which rotates cylinder 156, edge ring 140 and substrate 110 at speeds of at least approximately 90 rpm and as high as 1500 rpm or more.
Note that we have observed an effect (i.e., impelling purge gas in an outward radial direction) with rotation speeds as low as 20 rpm and positive results are produced with rotation speeds of 30-40 rpm.
A process gas 118 is introduced into the space between the substrate 110 and window assembly 102 through a side port 164. In other embodiments, process gas 118 passes into chamber through apertures (not shown) formed in window assembly 102 (described in the afore-mentioned co-owned patent application entitled "Novel Way of Introducing Gas into an RTP Chamber"), or though a shower head type of nozzle 20 (see FIG. 1) centrally positioned above wafer 10, such that process gas 118 is directed towards a frontside 188 of wafer 110. Gases are removed through exhaust port 166, which may be coupled to a vacuum pump (not shown).
A nozzle 134 that is approximately centered in reflector 104 directs a flow of a purge gas 132 to a central area of the back surface 126 of substrate 110. Nozzle 134 is coupled to a regulated supply 130 of purge gas 132 via tube 168 and channel 170 in base 106. Nozzle 134 directs purge gas, on average, approximately normal to the surface 126. In another embodiment, nozzle 134 can be structured to direct purge gas 132 upward and radially outward in a conical-shaped flow pattern. Of course, it should be understood that other methods for introducing this backside purge gas in a way that is compatible with this invention are readily implemented by persons skilled in the art.
An optional purge ring 172 is fitted into the chamber body and surrounds the quartz cylinder 156. Purge ring 172 has an internal annular cavity which opens up to a region above upper bearing race 158. The internal cavity is connected to a second regulated purge gas supply 174 through a passageway 176 and tubing 178. During processing, a second flow of purge gas 180 enters into the chamber through purge ring 172.
Alternatively, cylinder 156 can be structured to form passages for purge gas 132 to flow out of cavity 150 into the annular region between edge ring 138, cylinder 156 and purge ring 172.
Temperature probes 152 (only two of which are shown in FIG. 4) measure the temperatures at localized regions 122 of substrate 110. The temperature probes are sapphire light pipes that pass through conduits 154 that extend from the backside of base 106 through the top of reflector 104. Although only two measurement probes 152 are shown in FIG. 4, the described embodiment actually uses eight measurement probes distributed over the reflector 104 so as to measure the temperature at different radii of the substrate 110.
During thermal processing steps, support structure 104 is rotated. Thus, each probe 152 actually samples the temperature profile of a corresponding annular ring area on the substrate 110.
Referring now to FIGS. 5 and 6, edge ring 140 has an inner portion forming a ledge 138 that supports substrate 110 and an outer portion 144 that is supported by cylinder 156. In the above-described embodiment, the surface of ledge 138 is flat so as to create a good seal when contacted by the backside of the wafer. In this alternative embodiment, however, grooves 182 are formed in the upper surface 142 of ledge 138. The grooves extend in an approximately radial direction from the inner edge of the ledge 138, partially into the outer portion 144. The grooves 182 provide flow paths that allow the purge gas 132 to more easily flow between the substrate 110 and the supporting ledge 138 of edge ring 140. The outermost portions of grooves 182 include an arcuate upward bend 186 that redirects the flow of purge gas 132 past the peripheral edge 136 of substrate 110 upward and outward in a more axial direction.
While only sixteen grooves 182 are illustrated in FIG. 5, a greater number of grooves more closely spaced together around the ring may provide a more uniform outward radial flow of purge gas.
The upper surface 142 at the outer portion 144 of edge ring 140 is at an elevation approximately the same as the upper surface 188 of substrate 110.
In another embodiment, illustrated in FIGS. 7 and 8, the upper surface 142 includes ridges or vanes 190 structured to assist in moving the purge gas 132 and the process gas 118 outward and away from the edge ring 140.
The edge ring 140 is also designed to create a light-tight seal with the quartz cylinder 156. Extending from the bottom surface of the edge ring 140 is a cylindrically shaped lip 192 which has an outside diameter that is slightly smaller than the inside diameter of the quartz cylinder 156, so that it fits into the cylinder, as shown, and forms a light seal. Alternatively, lip 192 can be a larger diameter to form a light seal with the outer surface of cylinder 156.
Edge ring 140 has an outer radius that is larger than the radius of the quartz cylinder 156 so that it extends out beyond the quartz cylinder. The annular extension of the edge ring 140 beyond cylinder 156, in cooperation with purge ring 172 located below it, functions as a baffle which prevents stray light from entering the reflecting cavity 150 at the backside of the substrate. To further reduce the possibility of stray light reflecting into the reflecting cavity, edge ring 140 and purge ring 145 may also be coated with a material that absorbs the radiation generated by heating element 110 (e.g., a black or grey material).
In the described embodiment, the purge gas is an inert gas, e.g. argon, although other types of gases can also be used. The choice of gas depends upon the particular material used in the chamber and upon the process being performed in the chamber. For example, under other circumstances it may be desirable to use a purge gas that will react with the source gas to scavenge possible deposition material, e.g. H 2 or HCl.
In other embodiments, the purge gas 132 can be directed towards the backside of the substrate through multiple injection ports. The purge gas need not be directed near the center of the substrate, and the flow rates through the multiple injection ports do not need to be the same. The injection ports can also direct the purge gas at an angle to the substrate backside. It will be understood that, in general, regardless of the details of the manner in which the purge gas is introduced to the backside, the rotating substrate provides a pumping action that will pull the purge gas radially outward.
A particularly effective injector 300 for introducing the purge gas is shown in FIG. 9. The injector 300 extends up from the reflector plate 104 and includes a hollow cylindrical body 302 and a top plate 304 mounted on a post 306 that passes through the center of the cylindrical body 302. The top plate 304 is positioned above the cylindrical body so as to form a slit 308 which extends 360° around the periphery of the nozzle. Purge gas, which is introduced into the hollow portion of the cylindrical body from below, flows up through the injector and out of the slit 308. This produces a flow of purge gas that is substantially horizontal or parallel to the backside of the spinning substrate 110.
In a system for processing 300 mm wafers in which the backside of the wafer is 18 mm above the reflector plate 104, the injector 300 is 0.75 inch in diameter and 10 mm high. The slit is about 15 mils wide and is about 7 mm above the reflector plate 104. For such a structure, an appropriate gas flow rate might be about 5 liters/min of H 2 , depending of course on other process and system variables. The injector can be made of quartz or a gold plated metal (e.g. aluminum or stainless steel).
In the described embodiment, the injector 300 is located slightly away from the center of the reflector plate 104. The precise location depends on design features of the system. Some of the considerations for optimum placement of the injector in a multiple lamp RTP system, such as was described earlier, are the following. Since the presence of the injector perturbs the temperature profile of the wafer in the vicinity of where the injector is located, it is desirable to move the injector out towards the periphery of the spinning wafer. In that way, its net impact on any single location of the wafer is reduced because the outer regions of the spinning wafer are heated by multiple lamps of the heating element and any given location near the periphery does not feel the impact of the injector except for a small part of the rotational cycle. However, the further one moves the injector out towards the periphery of the wafer the more asymmetric becomes the flow of gas relative to the backside of the spinning wafer. To achieve a more asymmetric flow, which is of course desirable, the injector should be closer to the center, where it produces a greater impact on the temperature profile. Thus, the optimum location is determined by balancing these two competing effects, and it will tend to be close to but not at the center.
With regard to the height of the injector, it is desirable to position the slit as close to the backside of the spinning wafer as possible so as to get effective flow of purge gas against the spinning wafer. However, if the top of the injector is too close to the wafer, the region between the top of the injector and the backside of the wafer will tend to entrap gas or negatively impact the flow of purge gas in this region. Thus, the optimum height of the injector is determined by balancing these two competing effects.
Though we have shown nozzle 300 in an RTP system, it should be understood that it could also be used in any system in which the backside purge technique described herein would be useful.
Also note that the process and purge gases may be removed from the chamber through multiple exhaust ports, which may be distributed around the support structure.
Although the invention is especially useful in semiconductor fabrication processes in which the substrate is typically a disk-shaped semiconductor, we intend the term "substrate" to broadly cover any object that is being processed in a vapor process chamber. The term "substrate" includes, for example, semiconductor wafers, flat panel displays, glass plates or disks, and plastic work pieces.
In addition, the term "vapor processing system" is intended to broadly cover any process by which a surface of a substrate is altered by flowing a process gas over the surface. This can include CVD systems, RTCVD systems, RTO systems, RTN systems, and other vapor processing systems that are currently known or that may be developed.
Though we have described the system as including a front side gas injection system which uses a showerhead and produces radially symmetric gas flow, the invention also works in the case of side injection system which produces a gas flow as indicated by the arrows 18a in FIG. 2.
Other embodiments are within the scope of the invention. | A method of processing a disk-shaped substrate, or wafer, during a chemical vapor process includes a backside purge of the substrate with a purge gas. The backside purge is obtained by spinning the substrate about a central axis, directing a flow of the purge gas over the backside of the spinning substrate, and causing the purge gas to flow in an outward radial direction with the spinning substrate. An apparatus in a vapor processing system structured for conducting the backside purge includes a support mechanism structured and arranged to support the substrate and spin the substrate about a central axis, and a conduit coupled to a source of purge gas, structured and arranged to direct a flow of the purge gas over a backside of the substrate while the substrate is spinning such that the spinning substrate causes the purge gas to flow radially outward. | 2 |
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates to a system for locking adjacently positioned panels together and for suspending the assembled panels from a supporting member. A wide variety of techniques have been used in the past to install panels to overhead supporting structure, including by way of example, panels which are provided with locking flanges configured such that after the flanges of adjacent panels are aligned one of the panels is rotated relative to the other to lock the panels in place. Clips extending downwardly from the supporting member have sometimes been used to secure the adjacent flanges of the panels to the supporting member. In addition to the foregoing, the panels are sometimes fastened directly to the overhead supporting structure with the use of self-drilling fasteners. With these and other known panel locking systems in mind it is apparent that with the spring action panel interlock of the present invention it is possible to accomplish the following objectives believed to be heretofore unavailable. With the present invention, adjacent panels may be interlocked with only "linear" motion by merely urging the male flange of one panel into engagement within the female flange of an adjacent panel. Thus, the necessity of having to swing one panel over the other, or to use clips, or to pre-drill the support before beginning to assemble the panels, is eliminated. Moreover, with the present invention simple screwtype fasteners may be used to secure the panels to the overhead supporting structure from a position below the structure thus avoiding the necessity of having to work on top of the supporting structure. In addition, with the panel interlock of the present invention only very slight pressure by the hand is necessary to "snap" the interlocking flanges of adjacent panels together. But once assembled, the panels cannot unlock by reverse action under downward pressure since increasing the load on the panels results only in forcing the interlocking flanges into tighter engagement. This procedure of interlocking with only slight pressure while providing a fail-safe system against unlocking is applicable over a wide range of dimensional tolerances thus avoiding the necessity of precise orientation of the components of the interlocking system. Still further, the snap-action panel interlock of the present invention is suitable for use with a reinforcing member positioned between the interlocking flanges of adjacent panels for increasing substantially both the load bearing and spanning capability of the assembled panel system.
The foregoing advantages are accomplished with the spring action panel interlock of the present invention which features a first interlocking female flange of one panel that has a portion which extends from the panel to the supporting member, another portion that extends along the supporting member engaging same such that a fastener can secure this portion directly to the supporting member, and another portion that extends away from the supporting member terminating in an end which is spaced from the other portions of the flange and which is provided with a lip. The other interlocking male flange of an adjacent panel has a portion which extends from the panel and which engages only a part of the corresponding portion of the other flange so as to reduce the friction therebetween permitting longitudinal sliding of adjacent panels, and another portion which extends diagonally backwardly terminating in an end which engages the lip of the other flange. Under increased loading, the interlocked panels are forced into even tighter relationship as a result of the diagonally positioned portion of the male flange being forced into a position generally perpendicular to the remainder of the flange thus causing the end of the male flange to force the lip of the female flange outwardly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an end view of one of the panels illustrating the construction of the interlocking flanges formed at each end thereof, and the position of the panel just before being urged upwardly into engagement with the other panel which has been fastened to the supporting member;
FIG. 2 is an end view of the panel snap-fitted in place, and a portion of another panel ready to be urged upwardly into engagement therewith;
FIG. 3 is an end view of the interlocking flanges of adjacent panels illustrating movement of the diagonal portion of the male flange into tighter engagement with the female flange as pressure is applied to the panel;
FIG. 4 is a sectional view taken along line 4--4 of FIG. 5 illustrating the interlocking flanges of adjacent panels with a reinforcing member positioned therebetween to increase the load bearing and spanning capability of the assembled panels; and
FIG. 5 is a perspective view of the interlocking flanges of adjacent panels with the reinforcing member shown in dotted lines positioned only at the central portion of the panels.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The spring action panel interlocking system of the present invention is illustrated in FIGS. 1-2, wherein the reference numerals 10, 12 and 14 designate adjacent panels. The panels 10, 12 may be flat as illustrated in FIGS. 1-3 or curved as designated by the reference numerals 10', 12', in FIG. 4. Each of the panels consists of a wall 16 which may be flat or curved and which ternimates in interlocking flanges 18 and 20. The interlocking flange 18 is provided with a first section 22 that extends outwardly from the wall 16, it being apparent that the section 24 joins the section 22 to the wall 16 such that the section 22 is generally perpendicular to the wall 16. The flange 18 is also provided with a second section 26 that extends outwardly from the section 22 and which is generally perpendicular to the section 22. The flange 18 is also provided with a third section 28 that extends outwardly from the section 26 forming an angle with the section 26 which is approximately 90 degrees. The section 28 terminates in a lip 30. Since each of the panels 10, 12 and 14 is formed of a flexible material, for example, roll formed aluminum, it is apparent that the sections 22, 26 and 28 of the interlocking flange 18 are free to flex, as described hereinafter.
The interlocking flange 20 of each of the panels 10, 12 and 14 is provided with a fourth section 32 which extends outwardly from the wall 16, it being apparent that a section 34 joins the section 32 to the wall 16. A fifth section 36 extends from the section 32 such that the included angle between the sections 32 and 36 is slightly less than 180°. It will be apparent from the foregoing that when the sections 32 and 36 of the male interlocking flange 20 are positioned adjacent the section 22 of the female interlocking flange 18 only portions of the sections 32 and 36 engage the section 22. (See the space between flange sections 22, 32 and 36 in FIG. 2, for example) Each of the interlocking flanges 20 is provided with a sixth section 38 which extends diagonally from the section 36 terminating in a lip 40. It will be apparent from FIG. 2 that when the interlocking flanges 18 and 20 are assembled, the lip 40 of the section 38 engages the point of intersection of the section 28 and lip 30 of the interlocking flange 18.
Installation of the panels will now be described with reference to FIGS. 1-2. It will be apparent from FIG. 1 that the interlocking flange 18 of the panel 10 has been fastened to the overhead beam 42 with the fastener 44 which may, for example, be a self-drilling screw. The installer then positions the interlocking flange 20 of the next panel 12 immediately below the interlocking flange 18 of the mounted panel 10 and pushes upwardly thereon. The pressure of the male interlocking flange 20 against the female interlocking flange 18 causes the section 28 and lip 30 of the interlocking flange 18 to spring outwardly as the diagonal section 38 of the interlocking flange 20 springs downwardly and the sections 32 and 36 of the interlocking flange 20 spring inwardly towards the section 22 of the interlocking flange 18. Eventually, the lip 40 of the male flange 20 passes over the lip 30 of the female flange 18 at which time the sections of the interlocking flanges 18 and 20, as previously described, resume their original position.
It will be apparent that precise alignment of the fronts and rears of adjacent of the panels 10, 12 and 14 is unnecessary since after the interlocking flanges 20 have been inserted within the interlocking flanges 18 adjacent of the panels 10, 12 and 14 may be slided longitudinally relative to each other. Note further that since the sections 32 and 36 of the interlocking flange 20 intersect at an angle slightly less than 180° the result is to reduce the areas of the sections 32 and 36 which engage the section 22 thus reducing friction between the interlocking flanges 18 and 20. Reducing friction, of course, permits ease in longitudinal adjustment of the assembled panels. Moreover, the angular relationship between the sections 32 and 36 of the interlocking flange 20 limits the contact between the sections 32 and 22 to the area generally designated by the reference numeral 46 which results in reducing the tendency of the panels to have a "gap" between the adjacent sections 22 and 32, particularly if one of the sections is bent.
Once the panel 12 is snap-fitted to the panel 10, the interlocking flange 18 of the panel 12 is secured to the overhead beam 42 with the fastener 48, as illustrated in FIG. 2, afterwhich the next panel 14 is secured in place by snapping the male interlocking flange 20 of the panel 14 within the female interlocking flange 18 of the panel 12. It will now be apparent that the fasteners 44 and 48 are hidden from view.
The "fail-safe" feature of the panel interlock of the present invention is illustrated in FIG. 3 wherein the interlocking flanges 18 and 20 of adjacent panels 10 and 12 are shown in locked position. FIG. 3 illustrates how the interlocking flanges 18 and 20 resist unlocking under downward force F despite the fact that only minimal hand pressure is required to lock the interlocking flanges 18 and 20. When force F is applied to the panel 12 the interlocking flanges 18 and 20 resist unlocking as the interlocking flange 20 is forced into even tighter engagement with the interlocking flange 18, eventually resulting in the section 38 of the flange 20 being forced into a position generally perpendicular to the section 36 thereof and the section 28 and lip 30 of the flange 18 being forced outwardly. Thus, the panel 12 cannot unlock from the panel 10 unless and until the flanges 18 and 20 have distorted beyond that position illustrated in FIG. 3.
With the foregoing in mind, certain of the advantages of the spring action panel interlock of the present inention will be described. The adjacent panels 10, 12 and 14 are interlocked with a simple upward linear motion as distinguished from the swing-over motion that is frequently used. That is, during installation it is only necessary to push the panel upwardly into locking relationship with respect to a panel that has already been assembled. The panels 10, 12 and 14 may be attached to the overhead structure 42 with screw-type fasteners 44 and 48 from below, thus avoiding the necessity of working on top of the overhead supporting structure 42. Only easy hand pressure is required for snapping the interlocking flanges 18 and 20 together. While construction time and effort are significantly reduced, the arrangement of the sections of the interlocking flanges of the invention define a "fail-safe" interlock precluding the unlocking of adjacent interlocking flanges under downward pressure. Still further, after the interlocking flanges 18 and 20 are assembled by snapping in place, the adjacent panels 10, 12 and 14 may be easily moved longitudinally by sliding action because friction has been minimized by the angular relationship of the sections 32 and 36 relative to the section 22.
Turning now to FIGS. 4-5, the reference numeral 50 designates generally a reinforcing member that may be positioned within the interlock previously described for the purpose of increasing both the load bearing and spanning capability of the assembled panels 10 and 12. In this connection, it should be noted that flat bottom panels are not as strong under downward loading as structural type panels of comparable gauge metal. This is true because flat panels have considerably less metal under compression in their upper flange areas than do structural panels. Thus, it is necessary to use substantially heavier gauge metal in flat panels than in structural type panels to obtain equivalent loading capacity. But with reinforcing member 50, which is inserted between the interlocking flanges 18 and 20, it is possible to increase the amount of metal that is in a state of compression under loading and thus significantly increase the potential loading and span capability of a given gauge panel, with the additional economic advantage of not having to increase the gauge of metal thoughout the entire panel.
As illustrated in FIG. 4, the reinforcing member 50 consists of a section 52 which is positioned between the sections 32 and 36 of the flange 20 and the section 22 of the flange 18, and a section 54 which extends outwardly from the section 52 and which rests against the section 26 of the flange 18. The section 56 of the reinforcing member 50 extends outwardly from the section 54 and rests in abutting relationship against part of the section 28 of the flange 18. As illustrated in FIG. 4, the sections 54 and 56 may comprise portions of the reinforcing member 50 that are "folded" together.
Moreover, and as illustrated in FIG. 5, it is not necessary to have the reinforcing member 50 extend the entire length of the panels 10 and 12 because under extreme loading the adjacent panels 10 and 12 will fail by compressive buckling of the adjacent flanges 18 and 20 at the center of the span of the panels. Thus, optimum results may be obtained by running the reinforcing member 50 over the center one-half or one-third of the span of the panels 10 and 12. | A paneling system having a supporting member and a plurality of panels each of which is provided at the ends thereof with interlocking flanges, the interlocking flange located at one end of the panel having a portion extending from the panel to the supporting member engaging same and thereafter extending away from the supporting member terminating in an end that is positioned in spaced relationship from the remainder of the flange, a fastener securing the flange to the supporting member, and wherein the interlocking flange at the other end of the panel has a portion extending from the panel which engages only a part of the corresponding portion of the other interlocking flange extending to a point near the supporting member and thereafter backwardly toward the end of the other interlocking flange terminating in an end which engages the end of the other interlocking flange. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This case is related to co-pending U.S. patent application Ser. No. 09/201,378 “Remote Assistant” by Lawrence P. Zale, assigned to the present assignee.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention related to identifying electronic boards/software routines configurations over time at a plurality of remote sites.
2. Discussion of Prior Art
Many large, industrial machines such as steam turbines, generators, locomotives, ships, oil refineries, iron mills, stamping mills, factory tools are either impossible or impractical to bring into a shop for in-house measurements. These remote sites are now connected to a base by a remote link. Measurements and other data may be transmitted via the remote link between the remote site and the base.
This remote link may be hardwired, such as an dedicated phone line, Internet connection, or may be by a radio link. The remote link is typically used to perform remote diagnostics of the equipment.
Typically the remote link is used to identify a current configuration, and inventory of the types of boards in a device to provide accurate service advice. Each machine may use many different types of boards and software, and certain types may not be compatible.
Patents, Copyrights and Trademarks may cover certain electronic boards and software routines (‘protected property’). These may be licensed (by a Licensor) to a customer (Licensee) for a specified period of time, area of use, or conditions of use. Conditions of use may be contrary to a warranty and is important for the licensee to know. It is very difficult to discern if the protected inventions are being implemented according to their prescribed use. If is very difficult to try to discern their use since many are typically, on-site devices, and inaccessible. It may also be embarrassing to check up on customers, who are actually using the products according to the license.
Currently, there is the need for a system that automatically determines unauthorized boards and routines residing in a machine at a remote site, and also aids in determining the life cycle of boards and routines.
SUMMARY OF THE INVENTION
A remote inventory system monitors electronic boards/software routines in a machine situated at a remote site. The boards/routines are marked with a unique serial number that is machine-readable. A monitor program operates at the remote site to collect the serial numbers and other corresponding information and send this information to a base site.
The base is connected to the remote site through a remote link.
A processor located in the base runs a base program which looks up the serial numbers in a database and indicates remote sites which are using protected property that they are not authorized to use. The base program also may create a report of length of use of each board/routine and performance history of a specified board/routine over time. By entering information of the date, location and vendor a board/routine is sold to, allows the base to create a report of vendor activity.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a remote means of determining presence of protected property in a remote machine.
It is another object of the present invention to provide a means of remotely determining the performance history of boards/routines implemented over a period of time.
It is another object of the present invention to track the location of the boards/routines over a period of time.
Is another object of the present invention to identify boards/routines having a larger than acceptable number of errors in a predetermined time period.
BRIEF DESCRIPTION OF THE DRAWINGS
While the novel features of the invention are set forth with particulars 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, in which:
FIG. 1 is one embodiment of the present invention monitoring boards/routines of several remote sites.
DETAILED DESCRIPTION OF THE INVENTION
As discussed above, it is difficult to enter a remote site to determine the hardware and software configuration of complex machines. If one were to enter the site, many of the boards/routines are inside the machines. Even if one were to extract the boards/routines it would be difficult to tell two boards of the same type apart without the presence of optical bar codes.
Apart from identifying the types of electronics boards and/or versions of software programs used, as was the case and the prior art, only the types of boards/routines and their version numbers were identified for diagnostic purposes.
Unlike the prior art, it is now necessary to identify the exact board/routine for tracking the location, performance/maintenance/upgrade history, and presence of ‘protected property’ of a specific board/routine.
With the advent of Remote Service and Diagnostics, a whole world of automated possibilities for Intellectual Property (IP) tracking and enforcement opens. By marking each electronic board with a unique serial number, such as by burning it in a programmable read only memory (PROM), or ROM, each may be uniquely identified.
Each software routine in each software package, is uniquely identified by a machine readable unique serial number in the program object code or data section. This serial number will appear in a PROM, ROM location of a board. These will not be easy to discern to those not familiar with it. They would appear to be obscure words determined to be part of the required executable code, or a hardware status word.
The serial number can be encoded with information such as when and where it was created, hardware/software version, and patents or trade secrets which covers the device. This information may also be linked to the serial number had some locations such as the database at the base.
Auto Downloading
During system remote maintenance connections, this serial number is downloaded to a main location. Downloading has become common with the advent of Internet broadcasting “push” software, and Java applets which can automatically contact another site and send specified information, without requiring the operators of the remote equipment to initiate the download, and in many cases, the operators are unaware of the download.
The download of serial numbers may also occur upon request from the base. This is standard “pull” technology.
Remote Maintenance
The program running at the base receives the serial numbers and processes them. The base program has access to a database with a history of serial numbers for that site, the types of board/routine pertaining to each serial number, a performance history for that serial number, a list of locations the serial number has been, information about the original purchaser of the board/routine, date/location of purchase, a list of authorized users, and other pertinent information. From this information the base program may perform many different functions.
Change in Configuration
The serial numbers may be compared to previous inventory of serial numbers of boards/software for this device. By determining which boards/software have changed, and comparing it to previous stored configuration for this site, one can determine what has been modified. By also examining the performance of the boards, one may discern of the change improved or hurt performance.
Service Contracts
By tracking the serial number of the newly added boards software, and comparing these to the original serial number inventory, one may discern if the boards/software were modified, possibly invalidating the service contract, or warranties.
Software Use Licenses
By periodically downloading the serial numbers for the device, a determination of which software/boards are being used during given time periods may be determined. Licenses that are keyed upon the number of uses are now feasible. This may also be used as evidence to show use when use is denied. It may be a powerful tool since this information may periodically be provided to a main base.
Monitoring Competitors
A sales log may be maintained which keeps track of sales of boards/software, their serial numbers, date of sale, parties sold to, their locations, etc. A comparison of the sales log with the current serial numbers of a machine may be used to determine service competitor patterns of where, how much work is being done, when it was done, and in what geographic areas it was done. This will provide a map of occurrences of competitors servicing these machines.
Imprinting
A check for multiple or duplicate serial numbers from different sites should indicate “black market” knock-offs” or counterfeited boards/software. Since, as described above, the serial number each serial number is unique, boards/routines that a copied, will have the same serial number. As stated above, if the the serial numbers are not discernable to those who are unaware of them, they may assumed to be part of the required executable code, or hardware status words and copied wholesale by counterfeiters. Therefore, one copying the board/software will copy literally to retain functionality, and result in an exact copy with a duplicate serial number. A quick check as to the authorized party by the base program will result in the authorized Licensee, with the duplicate site having unauthorized copies. This should aid in licensing/infringement matters.
Identification of Boards/Routines
A serial number is stored in the ROM or within a software routine allows a monitor program at the remote site periodically read the serial number at the remote site and report it to a main base. The monitor routine may also send a stored datablock which has a performance log. Serial numbers may be easily appended to software, and data, even if they are “off-the-shelf”. For example, several words may be appended to a conventional program, with a new “end-of-file” marker added, and a new checksum or parity word calculated on the extended file.
This would operate in the same manner by replacing a ROM, with another having the embedded serial number.
Therefore, for ‘off-the-shelf” hardware, a ROM chip may to be removed, the code downloaded to a disk. The code is then has the additional words appended, an end of file marker is added, and a new checksum calculated. This extended code is then burned into a blank ROM chip and then used to replace the original ROM.
The monitor program knows the predetermined locations of the serial words in each board/routine, reads them and sends them across the remote link to the base for analysis. That monitor program may initiate this process by itself based upon some internal trigger event, such as an internal clock reaching a specified date/time, or may be triggered by a request from the base.
Reporting routine could also be set up on a schedule to “wake up” at a certain time, read serial numbers, then report to the GE main base.
In FIG. 1, a simplified block diagram of the present invention is shown. At least one remote site 40 , 50 , 60 is shown connected to a main base 20 . Each remote site is connected to base 20 with a remote link 100 which may be either hard wired, a radio link, or a combination of the two.
A complex machine 10 is situated at remote site 40 has at least one electronic board 13 and/or software routine desired to be monitored.
Board 13 has a means 15 for storing a unique, machine-readable serial number. This may be in the form of dedicated electronic circuitry, a ROM, EPROM, or PROM.
For software routines, a unique serial number is embedded in the software routine and is stored on a storage device 53 such as a hard disk. The microprocessor 51 at remote site 40 reads the routine and the serial number.
A monitor program is accessible by microprocessor 51 . This monitor program may be fed to the remote site 40 from base 20 , be prestored on disk 53 , ROM 21 , or RAM 19 of remote site 40 .
The monitor program may “wake-up” on its own, triggered by an internal clock at remote site 40 , or be triggered by a request from a microprocessor 31 in base 20 .
The monitor program takes an inventory of machine 10 and provides the required information over remote link 100 to base 20 .
Microprocessor 31 of base 20 runs a base program which may be stored in a storage device 33 , ROM 32 , or RAM 25 .
The base program may perform a number of functions as set forth above some of which require a database for storage of current information and retrieval of past information for a given site or serial number. This database is stored in storage device 33 .
Base program being run by microprocessor 31 may interact with a base user 2 through an input device 21 and provides its output to monitor 29 . Therefore the current boards/routines in a given site may be displayed. The past history or performance of a specific board/routine may be displayed.
An indication of the locations the board 13 /routine has been, where it was purchased, and the group that purchased the board/routine may also be displayed.
Base program running on microprocessor 31 may create map of activity of third party service organizations by identifying boards/routines which where sold to a specified group and tracking the location of these boards/routines over time.
While specific embodiments of the invention have been illustrated and described herein, it is realized that modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit and scope of the invention. | A remote inventory system employs unique serial numbers ‘burned’ into each board/software routine desired to be tracked. These boards/routines find their way into machines at various remote sites each connected to a base by a remote link. A monitor program is run by a microprocessor resident at each remote site. It periodically collects the serial numbers and other information regarding the boards/routines, and transmits the information to a base running a base program. The base program interacting with a database, determines the hardware/software configuration, performance history, tracks the lifecycle of a board/routine. It may also be possible to determine remote sites running unauthorized ‘protected property’. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to headrests for use with patients and in particular to headrest providing mandibular, or jaw, support.
2. Background of the Invention
Patient airway management is vital to appropriate patient care in a multitude of varying circumstances. The rationale supporting and driving this approach is the acutely injured person is often unable to maintain their own airway secondary to their lethargic, obtunded or unconscious condition. Even in the more controlled settings, such as operating room environments, patients about to undergo anesthesia are given medications that may impair the patient's ability to maintain their own airway. In all of these circumstances, appropriately trained medical personnel must intervene on behalf of the patient to establish and maintain patent airways in all of these patients. Securing a patent airway is taught to all medical care providers as the first step in appropriate management. See Resuscitating CPR, Looking at the Basics and Adjuncts, Mikel A. Rothenberg, M.D., Journal of Emergency Medical Services, February, 1996, pp. 45-50.
There are several recognized maneuvers medical personnel may use with these patients in order to adequately open the patient's airway. In one such emergency medical publication titled Trauma Life Support Manual, in chapter one: Respiratory Procedures, the authors Joseph E. Clinton and Ernest Ruiz, strongly recommend that some type of jaw thrust or chin lift maneuver should be performed on every unconscious patient to ensure airway patency. Id., chapter one, page one. However, a chin lift maneuver requires at least one hand in order to accomplish the maneuver and a jaw thrust maneuver uses two hands to complete the maneuver. In order to maintain the airway patency, the chin lift or jaw thrust maneuver must be maintained until the patient either regains consciousness and is able to protect their own airway or an artificial airway is placed by the emergency medical personnel, such as an oropharyngeal airway, an orotracheal airway, etc.
Opening and maintaining a patent airway is only the first step. Many patients requiring medical personnel to maintain a patent airway, also necessitate that the medical personnel undertake the task of breathing for the patient as well. Even with simple procedures such as a bag valve mask placed over the patient's mouth and nose, considerable skill and art are required to place the mask over the nose and mouth, obtain an adequate seal around these orifices, complete a jaw thrust maneuver, hold it, and then subsequently squeeze the bag in order to deliver the breath of air. Another difficulty is also encountered. Routinely, a patient is placed on a smooth, hard surface such as a long back board. When the medical care provider is ventilating the patient with a bag valve mask, a certain amount of pressure is required to seal the mask to the skin of the patient's face to deliver an adequate ventilation. This downward pressure causes the head to slide into a more neutral position drawing the chin toward the patient's chest. This position will fold the tongue and related structures down toward the laryngeal inlet restricting airflow during ventilation. Additionally, the round shape of the patient's occiput against a hard flat surface also creates a problem of lateral head movement, particularly prevalent during transportation to a medical facility. It is not uncommon for medical care providers to place the patient's head between the knees of the care provider to facilitate some degree of stabilization while the care provider is attending to the patient. As is evident, often seemingly straight forward procedures as securing an airway and giving a patient a breath of air require more hands than the medical provider has available. The space around an obtunded or unconscious patient's head is limited and only so many medical personnel will be able to work around the patient's head area.
Many ambulance, paramedic and rescue rigs providing emergency medical services in the field only carry two emergency medical personnel. Once the patient's initial emergency medical needs are provided, the patient is then transported in the vehicle with only one emergency medical provider in attendance while the other drives. Such staffing of emergency medical rigs for field work may stretch to such an extent a medical care provider's ability to provide adequate airway management as to become unsafe during transport.
There are a number of known headrests and cushion supports useful to those skilled in the medical arts. One such support cushion is disclosed in U.S. Pat. No. 4,259,757 issued Apr. 7, 1981 to Watson wherein a support cushion is described having two components useful for supporting a patient's head during various surgical procedures such as ear, nose and throat surgeries and endotracheal intubation. Watson discusses the need for obtaining appropriate airway alignment in order to carry out an endotracheal procedure but Watson does not disclose, teach or suggest any method or instrument to obtain this alignment and maintain it other than allowing the patient's head to rest on the head support cushion.
Another disclosure is contained in U.S. Pat. No. 2,199,479 issued May 7, 1940 to Cappel in which there is disclosed a pillow useful for resting a patient's head and neck on in order to assist an anesthesiologist or anesthetist by placing a slight extension in the patient's neck. This slight extension is achieved by placing the patient's head to rest in the central recess and a rim of the pillow under the neck. According to the Cappel disclosure this positioning makes it possible for the anesthetist to be relieved of the duty of using one of his or her hands in holding the patient's head in a correct position. As in the other disclosure, this disclosure also recognizes the need for positioning but does not disclose, teach or suggest any other mechanism or device for obtaining airway patency other than merely resting the patient's head and/or neck onto the surface of a pillow or cushion.
For those skilled in this art, the ideal patient positioning is to place the patient into or as near as possible to the "sniffing" position such that the patient's neck is slightly flexed at the cervicothoracic junction and is slightly extended at the cervicocephalic junction. When so positioned, a patient appears to be "sniffing". An adequate description of this procedure is detailed in the above-identified article by Clinton and Ruiz.
After placing the patient's head and neck in this position, the patient's jaw, or mandible, is then elevated away from the patient's neck in either a chin lift or jaw thrust maneuver. Elevation of the mandible away from the head and neck provides distraction of the tongue and associated connective tissue structures, including the mylohyoideus, hyoid bone, and hyo-epiglottic ligament attached to the epiglottis, lifting the tongue away from the area of the oropharynx and hypopharynx and the epiglottis from in front of the laryngeal inlet thus opening the patient's airway from the level of the vocal cords on out to the patient's lips. Once this patient positioning is achieved, any number of breathing techniques and establishment of secondary airways may be accomplished.
In trauma situations, the status of the patient's cervical spine is highly suspect. In these circumstances, the patient's cervical spine is immobilized with a rigid collar. Then a modified positioning is achieved where flexion or extension of the neck is not performed but the chin lift or jaw thrust maneuver is performed with all patient's whether or not they are placed in a cervical collar because of the need for providing an adequate and patent airway.
Placement of a cervical collar does not preclude the use of at least a jaw thrust maneuver as a first step in obtaining a patent airway. Cervical collars are designed to place the patient's head in a slight extension with the patient's chin resting on an upper surface of the cervical collar. In most circumstances, the presence of a cervical collar under the patient's chin precludes use of a chin life maneuver. In these patients, the jaw thrust maneuver is still available and is the maneuver of choice as the first step in obtaining an adequate and patent airway.
As mentioned, there are a number of headrest and head immobilizers known to those skilled in the art. All of these devices to lesser or greater extent assist health care providers in immobilizing or positioning a patient's head, relative to their neck and thorax. However, the need for assisting health care providers, particularly in trauma circumstances in the field, does not end with immobilization of a patient's head or spine. The very next step that is taught to all medical personnel trained to deliver emergency medical care, is to obtain and maintain an adequately patent airway. There is an immediate need for a device capable of providing mandibular support relative to a patient's head and neck in a position known to increase the patency of a patient's airway.
SUMMARY OF THE INVENTION
The patient jaw thrust support of the present invention comprises a device which is placed under a patient's head region at the occipito-cervical junction as a headrest having a jaw thrust support positionable on an upper surface of the headrest that is engageable with the patient's mandible, particularly at the angles of the mandible on either side. The present invention engages and thrusts out the patient's mandible in relationship to the patient's head and neck, distracting the patient's tongue and associated support structures, including the mylohyoideus, hyoid bone, and hyo-epiglottic ligament attached to the epiglottis, moving the tongue out of the oropharynx and hypopharynx areas and the epiglottis out from in front of the laryngeal inlet. The support to the mandible provided by the present invention is substantially equivalent to the two-handed jaw thrust maneuver used by health care providers in achieving the same goal of lifting the jaw and distracting with it the tongue and associated connective structures. The jaw thrust support of the present invention has two additional advantages. The first is freeing up the care giver's hands providing freedom to go on to other tasks to assist the patient further. Secondly, the jaw thrust of the present invention stabilizes the patient's head position, substantially limiting motion of the patient's head relative to their cervical spine.
The present invention uses materials and components having compression and conforming characteristics such that the jaw thrust support is not so compressible as to collapse and allow the jaw to sag, but compressible to an extent so as to allow conformation of the surface of the jaw thrust support to the contours of the angle of the mandible on either side. Achieving the proper ratio of support to acceptable deformation and contouring the mandible engaging surface of the jaw thrust support is important in the concept embodied by the present invention so as to eliminate focal or excessive pressure points in the skin and other structures such as the parotid glands found at each angle of the mandible.
The present invention also recognizes the need for fluid impermeable surfaces that are both durable and sterilizable. In trauma settings, as well as hospital settings, there is the ever-increasing need to eliminate the risk of contamination to health care providers and subsequent use patients. Adequate containment of potential contaminants and infectious agents can be accomplished by applying durable, sterilizable yet pliable fluid impervious materials in the cover of the jaw thrust support of the present invention.
Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a jaw thrust support in accordance with the present invention;
FIG. 2 is a perspective view of the jaw thrust support of in FIG. 1 rotated to view the opposite perspective;
FIG. 3 is a side elevational view of the device depicted in FIG. 1 with a profile of the surface contour at line 3--3 of FIG. 2 depicted in phantom;
FIG. 4 is a side elevational view from the opposite direction as that depicted in FIG. 3 and additionally including positioning a patient in reference to the jaw thrust support of the present invention with the posterior aspect of the patient's head and neck depicted in phantom; and
FIG. 5 is a side elevational view similar to that of FIG. 3 and in addition depicting the positioning of a patient wearing a C-Spine immobilizing collar with the posterior aspect of the patient's head and neck depicted in phantom.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1, 2 and 3, there is disclosed a jaw thrust support device 10 having a bottom surface 12, and an upper surface 14, a first end 16, a second end 18, and at least two jaw thrust supports 20, 22 depicted as protuberances from upper surface 14. Extending between bottom surface 12 and upper surface 14 is a head support surface 40 in a substantially circular shape forming a head recess 26. On upper surface 14 between jaw thrust supports 20 and 22, there is a neck support groove 24 which is co-extensive with head support surface 40 and a nape of the neck support surface 28 extending towards second end 18. In this preferred embodiment, there are ear hollows 30, 32 as part of upper surface 14 that are contiguous with and between jaw thrust supports 20, 22 and a second set of jaw thrust supports 34, 36 depicted as protuberances of upper surface 14 near first end 16. Jaw thrust supports 34, 36 are separated from each other by a cervical collar cleft 38 at first end 16.
The preferred embodiment as depicted in FIGS. 1-5 is a combination of two sets of jaw thrust supports having a first set of jaw thrust supports 20, 22 adapted for those patients not wearing a cervical collar. The second set of jaw thrust supports 34, 36 arranged on the same support device as the other jaw thrust supports are adapted for use on patients wearing a cervical collar. This particular combination has proven convenient as well as useful lessening the requirement for multiple jaw thrust support devices for different circumstances. It is not necessary to the present invention to limit the device to two pairs of jaw thrust supports. The present invention anticipates that a single pair of jaw thrust supports configured for supporting the jaw along with the head and neck, either with or with out a cervical collar, is also a part of the present invention.
As shown in the various figures, the preferred embodiment is substantially "U" shaped in configuration. It is anticipated that the present invention could alternately be constructed with a single set of jaw thrust supports. One alternative embodiment, not depicted, would be similar in construction to jaw thrust supports 20, 22 with a surface between them similar to neck support groove 24 and having a ramp and surface similar to nape of neck support 28. Such a device would be useful for those patients known to not have any cervical spine injury in either a trauma circumstance or in an in-house hospital setting such as pre-operative anesthesia preparation and during anesthesia delivery as well as during acute resuscitation of patients in the emergency room or in the hospital wards and rooms.
The present invention also anticipates a single set of jaw thrust supports similar to jaw thrust supports 34, 36 with a cleft between them similar to cervical collar cleft 38. In the absence of the combined device as depicted, the jaw thrust supports could be connected with a thin, flexible web-like material at a surface similar to and contiguous with lower surface 12 spanning the cleft between the two jaw thrust supports.
Construction of the present invention includes a number of materials known to those skilled in the art. To comply with OSHA standards or similar requirements, the preferred embodiment has an outer layer of fluid impervious polymeric material surrounding a polymeric foam shaped to provide the elements of the present invention. There are known to those skilled in the art a number of different suitable polymeric coatings and suitable polymeric foams. A typical example of a suitable fluid impervious polymeric coating is polyvinyl. An example of a suitable polymeric foam having depression, conformation, rebound, hardness and impact absorption suitable for use in a device according to the present invention is polyurethane. It is anticipated that a number of different polymeric materials are suitable and applicable in the present invention and it is not intended that the present invention be limited to just these polymers.
In operation and in reference to FIG. 4, jaw thrust support device 10 is positioned with lower surface 12 on a patient support surface such as a stretcher or back board, not shown. Alternatively, for trauma settings in the field, the patient support surface may be the actual ground on which the trauma victim is found. Jaw thrust device 10 is then positioned so that the patient's head will rest within head recess 26 and the patient's neck lays against and is supported by neck support groove 24 and nape of neck support 28, ramping down and towards the patient's shoulders. When positioned, the base of the patient's head is slightly elevated above the patient support surface. During the positioning of the head and neck, the patient's mandible comes to lay between jaw thrust supports 20, 22 which engage both angles of the mandible to the patient's right and left respectively. The weight of the patient's head is sufficient to maintain the head's position within head recess 26, so that engagement of jaw thrust supports 20, 22 at both angles of the mandible provide sufficient support so to keep the mandible out from the lower head and neck distracting the patient's tongue and associated support structures, including the mylohyoideus, hyoid bone, and hyo-epiglottic ligament attached to the epiglottis, moving the tongue out of the oropharynx and hypopharynx areas and the epiglottis out from in front of the laryngeal inlet.
Turning to FIG. 5, jaw thrust support device 10 is depicted for use with those patients additionally immobilized with a cervical collar. Jaw thrust device 10 is positioned so that the patient's head will rest within head recess 26 with the patient's neck supported by the cervical collar and the cervical collar lays within cervical collar cleft 38. When positioned, the base of the patient's head is not slightly elevated above the patient support surface thus not placing any undue flexion forces on the cervical spine. During the positioning of the head and neck, the patient's mandible comes to lay between jaw thrust supports 34, 36 which engage both angles of the mandible to the patient's left and right respectively. The weight of the patient's head is sufficient to maintain the head's position within head recess 26, so that engagement of jaw thrust supports 34, 36 at both angles of the mandible provide sufficient support so to keep the mandible out from the lower head and neck distracting the patient's tongue and associated support structures, including the mylohyoideus, hyoid bone, and hyo-epiglottic ligament attached to the epiglottis, moving the tongue out of the oropharynx and hypopharynx areas and the epiglottis out from in front of the laryngeal inlet.
The foregoing description is considered as illustrative only of the principles of the invention, and since numerous modifications and changes will readily occur to those skilled in the art, it is not the inventor's desire to limit the invention to the exact construction and operation shown and described herein. Accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the present invention. | A jaw thrust support suitable for engaging the angles of the mandible of a patient for accomplishing a jaw thrust maneuver to proved a patient with a patent airway. The device is constructed of polymeric materials suitable for conforming to the angles of the patient's jaw while continuing to provide suitable support to the jaw by distracting the jaw forward away from the patient's head and neck thus distracting the patient's tongue and associated support structures lifting the tongue from the patient's oropharynx and hypopharynx and lifting the epiglottis from in front of the patient's laryngeal opening. | 0 |
FIELD OF THE INVENTION
The present invention generally relates to the field of programmable sewing machines and, more particularly, to a tripping assembly for a programmable sewing machine which expands the normal range of travel of the machine's clamp assembly.
BACKGROUND OF THE INVENTION
Programmable sewing machines are known in the art of textile manufacturing to perform certain repetitive stitching functions in the manufacturing process. Programmable sewing machines are useful for repetitive stitching operations since numerous sewing patterns may be stored in a computer memory and subsequently accessed by an operator. Such sewing patterns can be used to produce a desired stitching design on the given material, namely by moving the material relative to the sewing needle with a clamp assembly (i.e., an arch clamp and a lower clamp plate which may be moved in both in the "X" and "Y" directions) which appropriately engages and moves the material relative to a sewing needle.
Programmable sewing machines, namely the clamp assembly, typically have a maximum range of motion in the "X" direction which is defined by the spacing between two limit switches on the machine. For example, when the limit switch spacing is two inches, the maximum range of motion of the clamp assembly is two inches. However, models are available with various ranges of motion such as a 2-inch, 4-inch, and 6-inch range. Regardless of the spacing, the limit switches are tripped in one commercially available machine by a one-piece tripping plate which is interconnected with the clamp assembly. When the clamp assembly is moving in one direction and the tripping plate trips a limit switch, the clamp assembly will be prevented from further movement in that direction. Similarly, the other limit switch limits movement of the clamp assembly in the opposite direction when tripped by the one-piece tripping plate.
In some instances, it may be desirable for the operator of a programmable sewing machine to obtain a range of motion of the clamp assembly which is slightly more than the maximum range of motion, without purchasing an upgraded and more expensive model with increased range capacity. Prior to the present invention, in one commercially available machine it was not possible to modify the machine to obtain a range of motion of the clamp assembly greater than the maximum range of motion of the machine without extensive modifications to the internal structure of the machine and which typically involved replacing pertinent components with "larger" components (e.g., widening the spacing of the limit switches and replacing the one-piece tripping plate with a larger one-piece tripping plate). Moreover, in some cases the expansion of the range of motion was only in one direction.
Accordingly, it is an object of the present invention to provide a means for extending the range of motion of the clamp assembly which does not require significant modification of the machine. It is a related object of the present invention to provide a two-piece tripping plate assembly that replaces an existing one-piece tripping plate of a programmable sewing machine to expand the range of motion of its clamp assembly, preferably in both directions.
SUMMARY OF THE INVENTION
The present invention is embodied in a sewing machine for stitching a pattern on a stitchable material. The sewing machine generally comprises a clamp assembly for engaging the stitchable material, a movable table for moving the clamp assembly along an axis (e.g., the "X" axis) in both first and second directions, the first direction being opposite the second direction, first and second limit switches mounted on the sewing machine for limiting the range of movement of the clamp assembly in the first and second directions, respectively, and a tripping assembly interconnected and movable with the clamp assembly and comprising first and second tripping members movable relative to each other for tripping the first and second limit switches, respectively.
During sewing operations, and typically during at least a portion of the movement of the clamp assembly in the first direction, a tripping portion of the second tripping member extends beyond a tripping portion of the first tripping member in the first direction. A moving assembly is provided for moving the second tripping member relative to the first tripping member, before the tripping portion of the second tripping member reaches the first limit switch, and typically as the clamp and tripping assemblies move in the first direction, to thereby prevent the second tripping member from tripping the first limit switch. By moving the second tripping member in this manner, the first tripping member is able to trip the first limit switch at the desired time and thereby terminate movement of the clamp assembly in the first direction. Before the tripping portion of the first tripping member reaches the second limit switch by movement of the clamp assembly in the second direction, and typically as the clamp assembly is moving in the second direction, the moving assembly moves the second tripping member relative to the first tripping member such that the second tripping member, and not the first tripping member, is able to trip the second limit switch to terminate movement of the clamp assembly in the second direction.
The second tripping member is movable between two positions to allow the first tripping member to trip the first limit switch and to allow the second tripping member to trip the second limit switch. In this regard, when the second tripping member is tripping the second limit switch during movement of the clamp assembly in the second direction, the second tripping member is in a first position relative to the first tripping member. In one embodiment, such first position corresponds with a tripping portion of the second tripping member extending axially beyond a tripping portion of the first tripping member in the first direction. In this case, the second tripping member may be biased in this first position by a biasing spring which interconnects the first and second tripping members. Correspondingly, when the first tripping member is tripping the first limit switch during movement of the clamping assembly in the first direction, the second tripping member is in a second position relative to the first tripping member. In one embodiment, such second position corresponds with the tripping portion of the first tripping member extending axially beyond the tripping portion of the second tripping member in the first direction.
The movement of the second tripping member relative to the first tripping member allows for the tripping of the two limit switches in the above-described manner. In one embodiment, the moving assembly which provides this movement comprises an engaging portion of the second member which engages a portion of the sewing machine during at least a portion of the movement of the clamp and tripping assemblies in the first direction. The engaging portion of the second tripping member extends axially in the first direction and is positioned such that it is misaligned with and thus is unable to trip either of the limit switches. The engagement of the engaging portion in the above-described manner thus inhibits movement of the second tripping member in the first direction while the first tripping member continues to move with the clamp assembly in the first direction. Such movement of the first tripping member continues until the first tripping member trips the first limit switch. During movement of the clamp assembly in the second direction, the engaging portion becomes disengaged with the sewing machine and the second tripping member returns to its first position for tripping the second limit switch. This return to the first position may be provided by the above-described biasing spring.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a programmable sewing machine;
FIG. 2 is a front sectional view taken along line 2--2 of FIG. 1 showing an x-y table assembly with a prior art tripping plate;
FIG. 3 is a top view of the x-y table assembly of FIG. 2;
FIG. 3a is an exploded perspective view of the x-y table assembly of FIG. 2 with the prior art tripping plate;
FIG. 4a is a perspective view of the tripping assembly of the present invention with the second tripping member in a first position relative to the first tripping member;
FIG. 4b is the perspective view of FIG. 4a with the second tripping member in a second position relative to the first tripping member;
FIG. 5 is a perspective view of the first tripping member of the tripping assembly of the present invention;
FIG. 6 is a perspective view of the second tripping member of the tripping assembly of the present invention;
FIG. 7 is a top view of the tripping assembly of the present invention;
FIG. 8 is a front view of the tripping assembly of the present invention;
FIG. 9 is an end view of the tripping assembly of the present invention;
FIG. 10a is a top view of the x-y table assembly utilizing the tripping assembly of the present invention with the second tripping member tripping the second limit switch of the sewing machine;
FIG. 10b is the view of FIG. 10a with the second tripping member initially engaging the sewing machine; and
FIG. 10c is the view of FIG. 10a with the second tripping member fully engaged with the sewing machine and the first tripping member extending beyond the second tripping member to trip the first limit switch.
DETAILED DESCRIPTION
The present invention will be described with reference to the attached drawings which illustrate the pertinent features thereof. FIG. 1 illustrates a typical electronic programmable sewing machine 20 which can utilize the present invention. Generally, the programmable sewing machine 20 includes a base 22 which supports the machine 20, a head 24 which contains many of the components of the sewing drive assembly (not illustrated) which reciprocate the needle bar 26 and thus the sewing needle 28 in the desired manner, and a cylinder bed 30 which has a needle hole 32 therein for receiving the reciprocating sewing needle 28 to work in conjunction with other sewing components contained therein. The base 22 further contains components which provide lateral movement to a clamp assembly 40. The clamp assembly 40 typically includes an arch clamp 42, to which is detachably connected an upper square clamp 44 as is known in the art, and a lower clamp plate 46 to which is connected to a lower square clamp 47. Both the arch clamp 42 and lower clamp plate 46 are detachably connected to an x-y table assembly 50 which is contained within the casting of the sewing machine 20.
In FIGS. 2-3a, there is shown an x-y table assembly 50 of a programmable sewing machine 20 utilizing a prior art tripping plate 52. The x-y table assembly 50 generally includes a fixed race 54 above which is positioned a timing belt 56 supported on either end by sprocket wheels 58. At least one of the sprocket wheels 58 is selectably rotatable to provide movement of the timing belt 56 over the fixed race 54 along the x axis 60. A race table 62 is slidably positioned within the fixed race 54 such that the race table 62 can move along the x axis 60 relative to the fixed race 54 by movement of the timing belt 56. In this regard, the race table 62 is connected to the timing belt 56 by a connector 59 such that movement of the timing belt 56 provides movement to the race table 62 along the x axis 60.
A mounting table 64 is slidably positioned on the race table 62 such that the mounting table 64 can move along the y axis 66 relative to the race table 62. The clamp assembly 40 is detachably connected to the mounting table 64 and is further slidably mounted on an x-rod 68 such that the clamp assembly 40 can move along the x axis 60 relative to the x-rod 68. The x-rod 68 is rigidly mounted to a yoke 69 which is secured to a y-rod 70 which is selectably moveable along the y axis 66 to move the x-rod 68 and clamp assembly 40 in the y direction. Consequently, it can be appreciated that by selective movement of the y-rod 70 and the timing belt 56, the clamp assembly 40 can be moved along the x and y axes 60, 66 to properly position a piece of material relative to the sewing needle 28 for sewing a preselected pattern on the material.
The x-y table assembly 50 is further provided with a tripping plate 52 rigidly mounted on the race table 62 and extending in the positive x direction 72. First and second limit switches 74, 76 are positioned on the sewing machine 20 such that, when the clamp assembly 40 is in its normal range of motion, the first limit switch 74 is normally-open and the second limit switch 76 is normally-closed by the tripping plate 52. The limit switches 74, 76 are further operatively connected to a control mechanism (not shown) of the sewing machine 20 such that the range of movement of the clamp assembly 40 along the x axis 60 is limited by the interaction between the tripping plate 52 and the limit switches 74, 76. That is, the clamp assembly 40 cannot move in the positive x direction 72 beyond the point where the tripping plate 52 trips (closes) the first limit switch 74 and cannot move in the negative x direction 78 beyond the point where the tripping plate 52 trips (opens) the second limit switch 76. A third limit switch 80 can be used to center the clamp assembly 40 relative to the first and second limit switches 74, 76. From the above description, it can be appreciated that the range of movement of the clamp assembly 40 along the x axis 60 is limited to the spacing between the first and second limit switches 74, 76.
Referring now to FIGS. 4-9, the tripping assembly 100 of the present invention replaces the tripping plate 52 of FIGS. 2-3a. The tripping assembly 100 includes a first tripping member 102 mountable on the race table 62 in a manner similar to the tripping plate 52 of the prior art, and a second tripping member 104 which is slidably connected to the first member 102. A spring 106 is attached between the first and second members 102, 104 to bias the second member 104 in a fully-extended position relative to the first member 102, as shown in FIGS. 4a, 7, and 8.
As is best shown in FIG. 5, the first member 102 is a longitudinally-extending L-shaped member having two mounting holes 108 through which two mounting screws (not shown) are inserted for securing the first member 102 to the race table 62. One longitudinally-extending slot 110 is provided in the first member 102 for slidably receiving two pegs 112 on the second member 104. A slot hole 114 is positioned on the ends of the slot 110 so that the pegs 112 on the second member 104 can be initially inserted into the slot 110. A notch 116 in the first member 102 defines a first tripping edge or portion 118 and is provided to increase movement of the clamp assembly 40 in the positive x direction 72, as is explained herein in more detail. A first spring mount 120 is positioned on the first member 102 for mounting one end of the spring 106 thereto.
Referring now to FIG. 6, the second member 104 of the tripping assembly 100 generally includes a body portion 122 and an extending portion 124. Two pegs 112 extend from the side of the body portion 122 and are positioned such that they can be inserted into the slot hole 114 of the first member 102, as noted above. The pegs 112 include a cylindrical shaft portion 126 of a diameter slightly smaller than the width of the slot 110, and a head portion 128 of a diameter larger than the width of the slot 110 to prevent the pegs 112 from becoming disengaged from the slot 110. The head portions 128 are further slightly smaller than the slot hole 114 of the first member 102 to facilitate assembly of the first and second members 102, 104, as described below. Referring to FIGS. 4a and 4b, a second spring mount 130 is provided for mounting the other end of the spring 106. The extending portion 124 is narrower than the body portion 122, thus defining a second tripping edge or portion 132 for increasing movement of the clamp assembly 40 in the negative x direction 78, as explained herein in more detail.
When the pegs 112 of the second member 104 are properly positioned in the slot 110 of the first member 102 and the spring 106 is attached to the first and second spring mounts 120, 130, an assembly is provided in which the second member 104 is biased in a first position wherein the second tripping edge 132 extends beyond the first tripping edge 118 in the positive x direction 72, as shown in FIG. 4a. Accordingly, it can be said that the second tripping edge 132 occupies a "tripping zone" generally corresponding to the area extending from the first tripping edge 118 in the positive x direction 72. Furthermore, the second member 104 can be slid in the negative x direction 78 relative to the first member 102 to a second position whereby the first tripping edge 118 extends beyond the second tripping edge 132 in the positive x direction 72, as shown in FIG. 4b. In this second position, the second tripping edge 132 does not occupy the tripping zone as defined above.
Referring now to FIGS. 10a-10c, there is shown a top view of an x-y table assembly 50 utilizing a tripping assembly 100 of the present invention. The tripping assembly 100 is mounted to the race table 62 in a manner similar to the tripping plate 52 of the prior art. As can be seen in FIG. 10a, the extending portion 124 of the second member 104 is misaligned with the limit switches 74, 76. That is, it does not fall within the tripping zone of the assembly and, therefore, it cannot trip either of the limit switches 74, 76. The first and second tripping edges 118, 132, on the other hand, are aligned with the limit switches 74, 76 (fall within the tripping zone) and will trip the limit switches 74, 76 if properly positioned. For example, if the race table 62 moves in the negative x direction 78 such that the second tripping edge 132 reaches the second limit switch 76, the body portion 122 of the second tripping member 104 will no longer block (e.g., the limit switch 76 opens) the second limit switch 76, as shown in FIG. 10a. As a result, the second limit switch 76 will be tripped, thereby sending a signal to the motor controller (now shown), and the race table 62 will be prevented from moving further in the negative x direction 78. As can be appreciated, the range of motion in the negative x direction 78 can be altered by changing the positioning of the second tripping edge 132 relative to the race table 62. For example, if the second tripping edge 132 is extended further in the positive x direction 72 relative to the race table 62, the race table 62 will be allowed to travel further in the negative x direction 78. Correspondingly, positioning the second tripping edge 132 closer to the race table 62 will result in the race table 62 having a smaller range of motion in the negative x direction 78.
As the race table 62 moves in the positive x direction 72, the extending portion 124 of the second member 104 will eventually engage the side wall 140 of the sewing machine 20, as shown in FIG. 10b. The interaction between the second member (104) and the side wall (140) of the sewing machine (20) provides a moving assembly for providing relative movement between the first member (102) and the second member (104). At this point, the second member 104 is prevented from moving further in the positive x direction 72. However, the first member 102 can continue to move in the positive x direction 72 by merely overcoming the force of the spring 106 (not shown in FIGS. 10a-10c for clarity). As the first member 102 continues to move in the positive x direction 72, the spring 106 will be extended and the first tripping edge 118 will eventually pass and extend beyond the second tripping edge 132 in the positive x direction 72.
Further movement of the first member 102 in the positive x direction 72 will eventually result in the first tripping edge 118 engaging and tripping (e.g., the limit switch 74 closes) the first limit switch 74, as shown in FIG. 10c, thereby preventing further movement of the race table 62 in the positive x direction 72. It can be seen, therefore, that the second tripping edge 132 is prevented from tripping the first limit switch 74. It should be appreciated that the range of movement of the race table 62 in the positive x direction 72 can be modified by changing the placement of the first tripping edge 118 relative to the race table 62. For example, providing a tripping assembly 100 with a first tripping edge 118 that extends further in the positive x direction 72 relative to the race table 62 will result in a smaller range of motion of the race table 62 in the positive x direction 72. Correspondingly, providing a tripping assembly 100 with a first tripping edge 118 that extends a shorter distance in the positive x direction 72 will result in a larger range of motion of the race table 62 in the positive x direction 72.
As a result of utilizing the tripping assembly 100 of the present invention, the range of motion in the positive and negative x directions 72, 78 is effectively increased. More specifically, the range of motion along the x axis 60 in both directions is increased by an amount approximately equal to the distance between the first tripping edge 118 and the second tripping edge 132. Accordingly, the range of motion along the x axis 60 of a programmable sewing machine 20 can be substantially increased without the need for changing the location of limit switches 74, 76 on the machine 20. Furthermore, the amount of the increase of motion allocated to the positive and negative x directions 72, 78 can be modified by changing the placement of the first and second tripping edges 118, 132 relative to the race table 62.
The foregoing description of the present invention has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings, and the skill and knowledge of the relevant art, are within the scope of the present invention. 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. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art. | An apparatus for increasing the range of movement of a clamp assembly of a sewing machine in two directions, one being opposite the other. The apparatus generally comprises a first tripping member interconnected and movable with the clamp assembly of the sewing machine and having a first tripping portion which is engageable with a first limit switch of the sewing machine. A second tripping member is interconnected with the first tripping member and has a second tripping portion which is engageable with the second limit switch. Generally, the second tripping member is movable relative to the first tripping member between first and second positions. The first position corresponds with the second tripping portion being positioned within a tripping zone for tripping the second limit switch, and the second position corresponds with the second tripping portion being positioned out of the tripping zone such that the first and not the second tripping member will trip the first limit switch. | 3 |
FIELD OF THE INVENTION
This invention relates generally to point-to-point data link-layer protocols, and more specifically to providing flow control at the data link layer for such protocols.
BACKGROUND OF THE INVENTION
For digital data communication, the functions necessary for communication are generally partitioned in a layered architecture. Layer 1, the physical layer, describes the electrical or optical signaling, mechanical, and timing characteristics of a data link. Layer 2, the data link layer, determines how signals transmitted and received by the physical layer should be interpreted; generally, the data link layer provides framing, and may also include authentication, network layer address negotiation, loopback detection, and multiplexing of higher-layer protocols. Layer 3, the network layer, is responsible for end-to-end addressing and routing of packets traversing a network (or collection of networks) generally consisting of many separate data links. Four additional higher layers can provide additional high-level functionality, including packet ordering, ensuring reliable transmission, error correction, flow control, etc.
The Point-to-Point Protocol (PPP) is a data link layer protocol. It is described in Internet Engineering Task Force (IETF) Request For Comments (RFC) 1661, “The Point-to-Point Protocol (PPP)”, (1994). As described in RFC 1661, PPP provides a method for encapsulating multi-protocol datagrams, a Link Control Protocol (LCP) for establishing, configuring, and testing a data link, and a family of Network Control Protocols (NCPs) for establishing and configuring different network-layer protocols.
PPP was initially envisioned for use with low-speed services, including modem connections using analog phone lines. It was found, however, that PPP served a wide variety of connection types, including high-speed lines. For instance, PPP is now deployed for use with SONET (Synchronous Optical Network) physical layer equipment, in what is known as PoS (Packet over SONET). PoS is described in IETF RFC 2615, “PPP over SONET/SDH”, (1999), using HDLC (High-level Data Link Control)-like framing as described in IETF RFC 1662, “PPP in HDLC-like Framing”, (1994). SONET physical links use an optical carrier with one of several defined data signaling speeds. For instance, OC-1, the slowest SONET format, signals at a rate of 51.84 Mbps (million bits-per-second). OC-12 is twelve times as fast, at 622.08 Mbps, and OC-192 is 192 times as fast, at 9,953.28 Mbps, almost ten billion bits per second.
SUMMARY OF THE INVENTION
Historically, the subject of rate control has been viewed as a problem solved by other data communication layers and not by PPP. In fact, the author of RFCs 1661, 1662, and 2615, William Simpson, followed and edited a design document in developing PPP that explicitly teaches that flow control is a feature not required by a point-to-point protocol:
Flow control (such as XON/XOFF) is not required. Any implementation of the ISPPP is expected to be capable of receiving packets at the full rate Possible for the particular data link and physical layers used in the implementation. If higher layers cannot receive packets at the full rate Possible, it is up to those layers to discard packets or invoke flow control procedures. As discussed above, end-to-end flow control is the responsibility of the transport layer. Including flow control within a point-to-point protocol often causes violation of the simplicity requirement.
IETF RFC 1547, “Requirements for an Internet Standard Point-to-Point Protocol”, (1993).
In contrast to this teaching, it is recognized herein that good reasons now exist for implementing flow control as part of a point-to-point protocol, instead of relying on transport-layer flow control. In reality, increased signaling speeds now allow situations where a PPP data link can overwhelm the computing resources used to process the data received on that link. This would not generally be the case, e.g., with one 56 Kbps PPP modem connection serving a 500 MHz desktop computer. But with a 10 Gbps PoS connection having limited receive buffer capacity, a fraction of a second's unavailability for the attached computing resources could cause buffer overflow and data loss. This is particularly likely to happen where the PoS link serves a node such as a packet router, which typically handles multiple sources of bursty data and/or is not usually a connection endpoint itself.
Consider, for example, an OC-192 PoS link between two data routers carrying primarily Internet Protocol (IP) packets. For TCP/IP packets, Transmission Control Protocol (TCP) includes TCP connection end-to-end flow control, which manages a receive buffer at each endpoint. But a single OC-192 PoS link between the two routers could conceivably carry data for thousands—even millions—of TCP connections, very few of which terminate at the same node that the PPP link terminates. As such, the TCP connections cannot effectively control (or even be aware of) the data rate on any particular intermediate PPP link of their end-to-end paths. Even if the TCP peers could attempt control, during a TCP end-to-end round-trip latency of a quarter second (for instance), 2.5 billion additional bits would arrive at the PPP receiver before a flow control command could cause a flow rate difference. To compound this flow control problem, many data sources using a PPP link may use a transport control protocol such as the User Datagram Protocol (UDP), which implements no end-to-end flow control.
If bits are simply dropped at a receiver because the network layer could not handle them fast enough, significant data losses, retransmission and slow-start inefficiencies, and noticeably degraded service will almost surely result. And the loss of data may be non-selective when a receive buffer overflows, such that low-priority and high-priority data have an equal chance of being discarded.
The present disclosure proposes an extension to PPP that is simple, robust, and provides for flow control across a PPP link. In one embodiment, the existing Link Control Protocol of PPP is extended to allow negotiation of flow control options. Once flow control is negotiated, a PPP receiver can insert flow control frames in its outgoing stream to inform its peer when flow rate should be changed. The flow control frames can simply be used to request a pause in all flows, or selected flows, at the transmit end. The transmitter, seeing a paused flow, can ideally implement policies to discard and/or buffer packets so as to cause less disruption than would be caused by discarding packets at the receive end.
BRIEF DESCRIPTION OF THE DRAWING
The invention may be best understood by reading the disclosure with reference to the drawing, wherein:
FIG. 1 illustrates a network segment containing nodes that communicate over PPP links;
FIG. 2 shows a simplified block diagram of a modular router;
FIGS. 3 and 4 contain block diagrams for router line cards according to two embodiments of the invention;
FIGS. 5–11 show LCP frame formats useful with embodiments of the present invention;
FIGS. 12 a–c illustrate link configuration message exchange according to embodiments of the invention;
FIG. 13 shows a PPP flow control frame format according to an embodiment of the invention;
FIG. 14 contains a basic flow chart for Simple Flow Control packet generation;
FIG. 15 shows a PPP flow control frame format according to another embodiment of the invention;
FIG. 16 contains a basic flow chart for Service Flow Control packet generation; and
FIG. 17 contains a basic flow chart for an implementation responding to Simple and Service Flow Control frames.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiments are described below with reference to particular implementations such as might exist in a high-speed router. Such implementations are exemplary, as a high-speed router is just one type of packet-processing device that uses point-to-point protocol communications and could therefore benefit from the present invention. In general, a “packet-processing device” could be a router, a layer-2 switch, a gateway, an agent, a general-purpose computer, or a subcomponent of one of these, such as a line card or a network interface card.
As an introduction, FIG. 1 shows a hypothetical network segment 20 . Four routers 30 , 40 , 50 , and 60 are connected by bi-directional PoS links: router 30 connects to routers 40 , 50 , and 60 via links 32 , 34 , 36 , respectively; routers 40 and 50 connect via link 42 ; and routers 50 and 60 connect via link 52 . It is not necessary to operation of one PoS link that each of these links is a PoS link—for example, some links could use ISDN or ATM (Asynchronous Transport Mode) circuits, Fast Ethernet, Gigabit Ethernet, or 10-Gigabit Ethernet formats.
Each of routers 30 , 40 , 50 , and 60 typically connects to other network nodes that are not shown in FIG. 1 , e.g., via connections 38 shown on router 30 . These other connected nodes could be any type of packet-processing device.
It can be envisioned from FIG. 1 that, depending on the demands of other nodes or partial equipment failure, bottlenecks could develop that would cause one of the illustrated routers, for instance router 30 , to fall behind in forwarding packets received on one or more of its high-speed PoS links. Or, one of the peers of router 30 may transmit its traffic, or some class of its traffic, at a rate higher than has been negotiated for a given link. Traditionally, router 30 would respond to such conditions by dropping packets, which may or may not cause the sources of those packets to slow down.
A router that has negotiated flow control on a PoS link according to the present invention has an option other than merely dropping packets. For instance, before—or as—router 30 begins dropping packets wholesale on PoS link 32 , it can send a PPP flow control packet to router 40 . The PPP flow control packet requests that router 40 pause some or all traffic on link 32 for a period of time. This may afford router 30 enough time to reduce its buffer fullness. Router 40 , to the extent that it has transmit buffer room, can retain packets during the pause time, or Possibly discard some packets in an intelligent manner.
Because the PPP flow control loop operates over a point-to-point link that the two peers have direct control over, the loop can respond quickly to changing conditions at the two nodes. This allows the peers to respond much quicker and more predictably than a discard scheme that relies on end-to-end flow control, and may alleviate the need for retransmission or slowing of some flows.
FIG. 2 shows some of the components of router 30 in more detail. Line card 70 contains physical media ports for PoS links 32 and 34 . Line card 72 contains other physical media ports, including a port for PoS link 36 . Line cards 74 and 76 contain physical media ports for supporting other data links, shown collectively as 38 . In a modular router, the number and types of line cards can be varied to support different networking roles and capacities.
Each line card connects to one or more internal ports on switch fabric 78 . For instance, line card 70 connects to switch fabric 78 via a port pipe 80 , line card 72 connects to switch fabric 78 via a port pipe 82 , etc. Switch fabric 78 performs traffic switching that allows each packet to enter the router at one line card port and egress the router on an appropriate egress port.
FIG. 3 shows a partial block diagram for one embodiment of line card 70 . An optical fiber 22 connects to optics 90 , which contains a light modulator for transmitting signals and a receiver for detecting signals transmitted by a peer. Serializer/deserializer (serdes) 92 creates the analog electrical waveforms that drive the light modulator from parallel digital data received on a bus from PoS interface 94 . Likewise, serdes 92 receives analog electrical waveforms after conversion by the optical receiver, detects a digital bitstream in those waveforms, and converts the bitstream to parallel digital data. The parallel digital data is transmitted to PoS interface 94 over a bus. Optics 90 and serdes 92 can be considered together as one example of a physical media port capable of point-to-point full duplex data transfer with a physical media peer.
PoS interface 94 converts data between the serdes parallel format and the packet processor format, performs other well-known PPP tasks, and participates in PPP flow control as will be described shortly. When PoS interface 94 receives an egress packet from packet processor 96 , it generates a frame check sequence (FCS), adds the FCS and flags the beginning/end of the frame, performs byte and bit stuffing as required, scrambles the data, and places the scrambled data in the appropriate SONET framing format. SONET-framed data is presented to serdes 92 for transmission over the optical link. As PoS interface 94 receives PoS data from serdes 92 , it decodes the SONET framing and reverses the process above to supply ingress packets to packet processor 96 .
Packet processor 96 works in conjunction with packet classifier 98 and content-addressable memory (CAM) 100 to perform packet routing and other packet header updating for each packet received. Ingress packets also receive a backplane header that aids in traffic shaping, queuing, and routing across the switch fabric. Packet processor 96 strips the backplane header for egress packets and places them in a format expect by PoS interface 94 .
When ingress packets leave packet processor 96 , they pass through a FIFO buffer 102 to ingress traffic manager 104 . Ingress traffic manager 104 polices incoming traffic, drops packets as necessary to keep traffic within a designated profile, and queues packets bound for the switch fabric in ingress queue memory 108 . As switch fabric queues fill, ingress traffic manager 104 notifies a switch fabric scheduler (not shown) of pending traffic via scheduler interface 112 . The scheduler notifies traffic manager 104 when to supply traffic from each queue to serdes 114 for switching through the switch fabric.
Egress traffic manager 106 performs analogous functions for egress traffic received from the switch fabric via serdes 114 . Egress queue memory 110 stores egress-side packets in queues for scheduling to packet processor 96 .
FIG. 3 shows two additional control lines useful with one embodiment of the invention. Control line 120 allows ingress traffic manager 104 to signal flow controller 118 whenever a flow control packet could help reduce congestion in ingress queue memory 108 . Control line 122 allows flow controller 118 to signal egress traffic manager 106 when a PPP flow control packet has been received from a peer. After introduction of exemplary PPP flow control formats and option negotiation, operation of this embodiment will be further explained.
FIG. 4 is identical in most respects to FIG. 3 . But in FIG. 4 , packet processor 96 has been identified as a packet processor 116 that includes an IEEE802.3 Media Access Controller (as used herein, IEEE802.3 refers to the group of well-known standards promulgated by the Institute of Electrical and Electronics Engineers, referred to by the numbering prefix “802.3”, and defining what is often referred to as “Ethernet” protocol). Although IEEE802.3 is not technically a point-to-point protocol, IEEE standard 802.3x (“IEEE802.3x”) does provide a rudimentary flow control functionality that is exploited in the embodiment of FIG. 4 . In this embodiment, flow controller 118 processes received PPP flow control packets by repackaging them in a format recognizable by the IEEE802.3 MAC and passing them to packet processor 116 . The IEEE802.3 MAC recognizes the packets as if they had come from an IEEE802.3 MAC peer and pauses the outgoing packet stream accordingly.
Likewise, the IEEE802.3 MAC can generate IEEE802.3x MAC control frames when a pause in incoming packet flow is desired. Flow controller 118 captures such packets, repackages them (if PPP flow control has been negotiated), and sends them to a PPP peer.
FIGS. 5 through 11 illustrate packet formats useful with some embodiments of the invention. FIG. 5 shows a PPP frame conforming to RFC 1662. Flag sequences 152 and 166 contain the octet 0x7e (where the prefix 0x designates hexadecimal notation). The flag sequences delineate the beginning and end of a PPP frame. Address field 154 and control field 156 are also set to specific values (0xff and 0x03, respectively) that identify a valid PPP frame. Protocol field 158 identifies the protocol to be applied to payload 160 , which can, e.g., contain an IP datagram. Padding 162 can be used as appropriate, and is followed by a FCS 164 that provides error detection.
In addition to encapsulating IP and other datagrams, a PPP implementation can insert frames in an outgoing data stream—with protocol fields to designate that such frames contain a direct communication to a PPP peer. One example of such a protocol is Link Control Protocol (LCP), which is defined in RFC 1661. LCP frames have their protocol field set to 0xc021, and contain a message to the PPP peer in their payload. Among other things, these messages are used to negotiate the configuration of a PPP link.
FIG. 6 shows one type of LCP frame that can be generated by a device operating according to an embodiment of the invention. Frame 170 illustrates a Configure-Request LCP frame—a PPP implementation receiving frame 170 recognizes it as such by the LCP protocol in protocol field 158 and the LCP code 0x01 in code field 171 . The identifier field 174 contains a value that distinguishes the Configure-Request frame from other Configure-Request frames that the originator may have recently sent. The length field 176 allows the receiver to know when to stop reading options from the message.
The Configure-Request frame contain options that pertain to the frames received by the sender of the request. Many options have defaults, which will be used if an option is not included in a Configure-Request frame. Those options that are present are to be presented in ascended order according to option type. In the example of FIG. 6 , three unspecified options 178 , 179 , and 180 are shown preceding a new option, which is illustrated in field 182 as having a type 0x09 corresponding to a new flow control option. If the flow control option is missing from a Configure-Request frame, the default behavior is no flow control. If the option is present, the sender is requesting the ability to send flow control frames to regulate its inflow of data frames.
Upon receiving a Configure-Request with a flow control option, a PPP implementation has three choices, illustrated by FIGS. 7 , 8 , and 9 , respectively. If the PPP implementation accepts all of the requested configuration parameters, it returns a Configure-Ack LCP frame 190 to its peer, with the same identifier as the Configure-Request frame, and the same options that were requested. Upon receiving frame 190 , the configuration-requesting node has successfully negotiated a flow-control option that allows it to send flow control frames to its peer.
In some situations, a PPP implementation may be willing to accept flow control instruction, but not according to the option requested in frame 170 . In such a situation—and assuming that the other options in frame 170 are acceptable—the appropriate response is to return a Configure-Nak LCP frame 200 . The Configure-Nak frame contains the rejected flow control option, but fields 204 and 206 will pertain not to the original option parameters of fields 184 and 186 , but to a new set of option parameters that would be acceptable to the peer. More than one set of option parameters could exist in the Configure-Nak frame, if more than one set is acceptable.
Another Possible response to a Configure-Request frame is illustrated by Configure-Reject LCP frame 210 in FIG. 9 . The Configure-Reject frame instructs the Configure-Request sender that one (or more) of the requested options cannot be negotiated or cannot be recognized, e.g., in the present illustration when the peer does not have flow control capability. The unacceptable option is returned in field 212 .
At least two different types of flow control options are envisioned for the LCP protocol—Simple Flow Control and Service Flow Control. FIG. 10 shows a typical Simple Flow Control Option field 182 with its appurtenant fields 184 and 186 . Option length field 184 contains the length in octets of the entire option, including fields 182 , 184 , and 186 . Field 186 , the option payload, contains two nested information areas. Flow control type field 222 contains the value 0x01, which indicates this is a Simple Flow Control option request. Flow control length field 224 contains the length in octets of the flow control option payload, including fields 222 , 224 , 226 , and 228 . Field 228 contains the Simple Flow Control option parameters.
Within field 228 , a Simple Flow Control type field 230 must have the value 0x01, which means that the flow control type is a pause time out (the protocol could be expanded to include other types of Simple Flow Control, such as percent rate reduction, by adding other valid type values). Simple Flow Control length field 232 contains the length in octets of field 228 . Pause Time Out field 236 contains the number of byte times that a pause time out can occupy, where a “byte time” is defined as 8/(link speed in bps).
FIG. 11 shows a typical Service Flow Control Option field 182 with its appurtenant fields 184 and 186 . Flow control type field 222 contains the value 0x02, which indicates that this is a Service Flow Control option request. Fields 242 , 244 , and 246 contain the Service Flow Control option parameters, each of these fields representing a service class. This allows the peers to negotiate a number of service class IDs, the priority associated with each ID, and the flow control behavior for each ID. Up to sixteen service class IDs and priority values can be assigned in the illustrated format.
Considering field 246 as exemplary, sub-field 248 indicates the Service Flow Control option format followed in field 246 —in this case, the Service Class option 0x01(other option classes could also be defined). Service Flow Contact length sub-field 250 indicates the total length of field 246 . Priority field 254 indicates the priority assigned to the service class indicated in Service ID (SID) field 256 . Finally, pause time out sub-field 258 contains the number of byte times that a pause time out can occupy, where a “byte time” is defined as 8/(link speed in bps). In this format, up to sixteen priorities and sixteen SIDs can be defined. The priorities and SIDs need not map one-to-one.
With packets, flow control options, and option parameter formats described, several exemplary LCP option negotiation sessions will now be described. FIG. 12 a illustrates a negotiation session between two PPP peers, Node 1 and Node 2 , that each implement Simple Flow Control and Service Flow Control as described above. During options negotiation, Node 1 sends Configure-Request frame F 1 to Node 2 . Frame F 1 requests both Simple Flow Control and Service Flow Control (PFCP) be allowed. Frame F 1 may contain other PPP options as well, but these have been omitted for clarity. As these requests are acceptable to Node 2 , Node 2 returns Configure-Ack frame F 2 , repeating the identifier and options of frame F 1 . Node 1 then knows that it can send either Simple Flow Control or Service Flow Control frames to Node 2 during this session.
Node 2 negotiates the parameters for its end of the link by sending FCP frame F 3 to Node 1 , requesting only Simple Flow Control capability. Although Node 1 could handle Service Flow Control, it agrees to respond to only Simple Flow Control frames by repeating the parameters of frame F 3 in Configure-Ack frame F 4 .
FIG. 12 b illustrates an LCP option negotiation session where Node 2 cannot operate according to the Service Flow Control protocol. Node 1 , unaware of this, sends Configure-Request frame F 1 to Node 2 to request four-class Service Flow Control. Node 2 refuses the request by transmitting a return Configure-Nak frame F 2 . Frame F 2 contains a flow control option with parameters that would be acceptable to Node 2 , e.g., Simple Flow Control with a suggested Pause Time. The Pause Time could, for instance, correspond to the available transmit buffer space that Node 2 could use to buffer frames during a pause. Node 1 transmits a new Configure-Request frame F 3 , including the Simple Flow Control parameters received in frame F 2 . Node 2 accepts the options of frame F 3 by returning a Configure-Ack frame F 4 . Node 2 also negotiates Simple Flow Control for its end of the link as shown in frames F 5 and F 6 , in similar fashion to the previous example.
FIG. 12 c illustrates an LCP option negotiation session where Node 2 either does not recognize or refuses to participate in flow control. Node 1 , unaware of this, sends Configure-Request frame F 1 to Node 2 to request Simple Flow Control. Node 2 returns Configure-Reject frame F 2 , repeating the flow control option to inform Node 1 that it will not accept any flow control option. Unless Node 1 wants to drop the connection, it must transmit a new Configure-Request frame F 3 that contains no flow control option. As this is of course acceptable to Node 2 , Node 2 returns a Configure-Ack packet F 4 . Node 2 also negotiates its end of the link with Configure-Request frame F 5 , which contains no flow control option. As the default behavior is no flow control, Node 1 returns a Configure-Ack packet F 6 and neither end of the link will use flow control.
As illustrated by the above examples, the proposed flow control extensions to the LCP protocol can provide a simple, robust, and orderly process for negotiating PPP flow control, even when the PPP nodes have different (or no) flow control capability.
Assuming that PPP flow control has been negotiated, a conforming endpoint can then generate and respond to PPP flow control frames, as will now be described. Although one protocol type could, in some embodiments, be used for both Simple and Service Flow Control, there can be advantages to having separate protocol types for Simple and Service Flow Control.
In one embodiment, Simple Flow Control has its own PPP protocol, which will be referred to as SFCP. The value for this protocol, e.g., 0xc4c1, is inserted in protocol field 158 of FIG. 5 , and the flow control payload is inserted in payload field 160 . Referring to FIG. 13 , the SFCP payload 160 is illustrated with four fields 270 , 272 , 274 , and 276 . This payload is, not coincidentally, the same payload carried by an IEEE802.3x PAUSE frame (albeit without a MAC header). MacControl field 270 contains the opcode 0x0001, which to an IEEE802.3 MAC signifies a PAUSE frame. PauseTime field 272 contains a request for a time to pause traffic, expressed in 512-bit times. Fields 274 and 276 contain padding expected by an IEEE802.3 MAC.
With a device like that of FIG. 3 , SFCP frames can be generated with flow controller 118 and PoS interface 94 according to flowchart 300 of FIG. 14 . At block 302 , flow controller 118 receives notification of receive buffer fullness over signal line 120 , e.g., as a value BufferLevel. Block 304 compares BufferLevel to a threshold T. If BufferLevel is below T, control is transferred to block 308 , which places the flow control loop in a wait state until it is time to reevaluate BufferLevel. But if BufferLevel is above T, control is transferred to block 306 , which causes a PPP frame with a payload like that of FIG. 13 to be generated and placed in the PPP output stream.
Although signal line 120 is shown in FIG. 3 as originating from ingress traffic manager 104 and terminating at flow controller 118 within PoS 94 , many other Possibilities exist. The flow controller could reside within PoS interface 94 , within the ingress traffic manager, or within packet processor 96 . The buffer of interest could be queue memory 108 , FIFO 102 , or an internal buffer within one of blocks 94 , 96 , or 104 .
In one implementation, exemplified by FIG. 4 , packet processor 116 comprises an IEEE802.3 MAC capable of generating IEEE802.3x control frames. Due to the intervening PPP link, the MAC cannot communicate with an IEEE802.3x peer at the other end of the link—indeed, it is possible that no such peer exists even if it were possible to peer across the PPP link. But if so enabled, the MAC can generate IEEE802.3x control frames. PoS interface 94 scans for such frames: if SFCP is disabled, PoS interface 94 removes these MAC control frames from the outgoing data stream; if SFCP is enabled, it extracts the IEEE802.3x payload from the MAC control frame, repackages it as a PPP SFCP frame, and transmits it to the peer.
The logic that causes generation of a SFCP frame could have varying degrees of complexity beyond a simple one-threshold comparison. For instance, if the threshold is surpassed, the generated PauseTime could be a function of how far the threshold is surpassed. Multiple PauseTime values could be paired with multiple thresholds. Or the rate of change of the variable BufferLevel could be calculated and used to evaluate when to generate an SFCP frame. The round-trip latency of the link could be estimated, e.g., during LCP link initialization, and used as a parameter in the frame-generation logic. The logic may not even relate to buffer fullness at all, but to another measure, such as whether the PPP peer is exceeding an allocated average flow rate.
In one embodiment, Service Flow Control also has its own PPP protocol, which will be referred to as PFCP (Priority Flow Control Protocol). The value for this protocol, e.g., 0xc4c3, is inserted in protocol field 158 of FIG. 5 , and the flow control payload is inserted in payload field 160 . Referring to FIG. 15 , the PFCP payload 160 is illustrated with fixed-length fields 280 , 282 , and 284 , and a variable-length field comprising fields 286 and 288 . Type field 280 must contain the value 0x01, which corresponds to a Service Pause format (other formats can of course be devised for other schemes). Length field 282 indicates the total length of payload 160 in octets. Service fields 286 and 288 have identical formats, but in a given packet will pertain to different service classes. The number of such fields in payload 160 can vary between one and sixteen in the disclosed implementation. The PFCP receiver can detect the number of fields present from length field 282 .
Considering service field 288 as exemplary, it contains two sub-fields 290 and 292 . Sub-field 290 contains a valid SID. Sub-field 292 contains a corresponding PauseTime for that SID, expressed in byte times. Zero is a valid value for sub-field 292 , and indicates that the corresponding SID may restart transmission immediately (if paused).
With a device like that of FIG. 3 , PFCP frames can be generated with flow 15 : controller 118 and PoS interface 94 according to flowchart 350 of FIG. 16 . At block 352 , flow controller 118 receives notification of receive buffer fullness over signal line 120 , e.g., as a value BufferLevel, and sets a counter value n to zero. Blocks 354 , 356 , and 358 comprise a loop that compares BufferLevel to thresholds from a threshold array T[n], with an array size ServiceClassSize equal to the number of negotiated service classes. At block 354 , if BufferLevel is above T[n], control is transferred to block 356 and 358 , which respectively increment n and then check whether n has reached the top of the array. If the top of the array has not been reached, another loop is initiated to compare BufferLevel to the next threshold. If the top has been reached, control passes to block 364 . If, however, block 354 found a T[n] greater than BufferLevel prior to reaching the end of the threshold array, control passes through block 360 before passing to block 364 . Block 360 checks n, and if n is zero (BufferLevel below all thresholds), control passes to block 362 where the routine waits for the next evaluation time. Block 364 generates a PFCP flow control frame, and includes subblocks for calculating packet length (block 366 ) and a loop for generating service fields for the SIDs to be paused (blocks 370 , 372 , and 374 ). Note that an array of PauseTimes is used to generate the frame, allowing each SID to have a unique PauseTime.
Flow chart 350 could have additional levels of complexity, some of which were suggested above for flow chart 300 ( FIG. 14 ). Other possibilities include basing PauseTimes on recently observed statistics for the bandwidth occupied by various service classes—this suggestion recognizes that flow control may be ineffective if it does not affect the major users of bandwidth. Such statistics could be made available from ingress traffic manager 104 ( FIG. 3 ).
When flow control packets are generated by one PPP endpoint, the PPP peer of that endpoint has agreed to detect and respond to those packets. FIG. 17 shows an exemplary packet-processing flow chart 310 for a device that can receive either SFCP or PFCP frames. As ingress frames are processed by, e.g., PoS interface 94 of FIG. 3 , blocks 312 and 314 compare the ingress frame protocol field value to the values that signify an SFCP or PFCP frame. If an ingress frame protocol field has neither value, block 316 passes the frame to the packet processor (assuming that the protocol is not another recognized PPP frame type, such as an LCP, PAP, or CHAP frame. In reality, a check to see if the first octet of the protocol contains 0xc0 or higher could be used as a prefilter for all these protocol types as well as SFCP and PFCP). Block 318 then gets the next frame header and the process repeats.
When the frame protocol matches the SFCP protocol type, control transfers to block 320 for a check as to whether SFCP was negotiated and is active for the link. If not, block 322 discards the frame, and could also Possibly generate a LCP Protocol-Reject frame back to the peer. If SFCP is active and negotiated, the PauseTime transmitted by the peer is extracted from the frame at block 324 . Block 326 sets a resume timer and signals a stop of egress packet flow, e.g. to egress traffic manager 106 over signal line 122 of FIG. 3 . At the expiration of the timer, another signal can restart egress packet flow.
When the packet processor can recognize and respond to IEEE802.3x PAUSE control frames, as can packet processor 116 of FIG. 4 , blocks 324 and 326 are unnecessary. Instead, the SFCP frame can be repackaged as an IEEE802.3x PAUSE control frame and passed to packet processor 116 for flow pausing.
When the frame protocol matches the PFCP protocol type, control passes from block 314 to block 330 for a check as to whether PFCP was negotiated and is active for the link. If not, block 332 can take discard action similar to that of block 322 . If PFCP is active and negotiated, block 324 extracts two arrays of N values from the frame, a Service ID array SID[n] and a pause time array PauseTime[n]. Block 326 then signals egress traffic manager to stop each ID in SID[n] for the corresponding PauseTime[n]. Note that flowchart 310 will likely include additional steps to check that the transmitted flow control fields make sense—such steps have been omitted for clarity.
Several embodiments have been presented herein. Those skilled in the art will recognize that depending on the particular packet-processing device, PPP flow control functionality could be embodied in hardware, software, or a mixture of the two. For a software embodiment, an embodiment can comprise computer instructions contained on a computer-readable medium, i.e., optical, magnetic, or semiconductor storage devices. When such instructions are executed or interpreted by one or more processors within a packet-processing device, they cause the packet-processing device to perform PPP flow control functions such as described above.
Although the currently published PPP implementation has been referenced herein, it is recognized that PPP will likely evolve in the future, or that other PPP-like protocols are Possible. The scope of the attached claims is intended to cover all such point-to-point data link layer protocols, but not protocols that operate at different layers (such as TCP), or protocols such as IEEE802.3, which use source/destination addressing and are operable on multiple-access data links. | Method and apparatus are disclosed for flow control over Point-to-Point Protocol (PPP) data links. A method of negotiating such flow control between two PPP peers is disclosed, along with methods for operating flow control across a PPP link. In one embodiment, flow control frames carry an IEEE802.3x MAC control frame payload—the PPP implementation repackages such frames as MAC control frames and passes them to a MAC, which performs flow control. In another embodiment, flow control frames allow flow control commands to be applied differently to different service classes such that PPP flow can be controlled on a per-class basis. | 8 |
FIELD OF THE INVENTION
This invention relates to coupling devices for electrical fixtures, such as connecting a lamp to a ceiling or wall outlet.
BACKGROUND OF THE INVENTION
It is appreciated that it is very awkward and potentially hazardous for the average person to wire or rewire electrical connections involving electrical fixtures, such as lamps, outlet plugs and the like. Normally, this sort of work is left to the skilled tradesman; however, there are many householders who for various reasons wish to make their own installations. It would therefore be expedient for both the skilled tradesman and the householder to have a simple hazard-free form of installing lamp fixtures and the like on wall and ceiling outlet boxes. This problem has been appreciated for some time and as a result many solutions have been posed as exemplified in the following patents.
A simple form of plug-in arrangement is disclosed in U.S. Pat. Nos. 1,486,896; 1,511,594 and 2,671,821. The wall or ceiling outlet box has provided in a sealed face thereof a standard type of plug outlet. The lamp to be secured to the outlet box has a base plate which is coupled in one form or another to the outlet box. Before such coupling is completed, the lamp fixture plug is simply plugged into the outlet plug of the electrical box. This type of arrangement reduces hazard in the average householder making connections and for the skilled workman provides an expedient form of connection. It is appreciated, of course, that the outlet box has to have been prewired by a competent individual.
All of the devices described in the aforementioned patents significantly protrude into the electrical outlet box (or wall or ceiling if there is no such box). This degree of protrusion into the electrical outlet box is in contravention of most electrical safety codes. Furthermore, all of the devices described in the prior art patents require two or more steps for detachment or mounting of a fixture within appropriate connector.
In addition, the prior art devices cannot be used universally for connecting a wide variety of fixtures. For example, the devices of U.S. Pat. Nos. 1,486,896 and 1,511,594 are designed specifically for wall mounting wherein the downward weight of the fixture is required to maintain the connection. U.S. Pat. No. 2,671,821 discloses a hanger system limited to hanging type fixtures.
Canadian patent No. 1,040,606 discloses an electrical coupling system which simultaneously provides for electrical contact of the fixture to the outlet box wiring, while securing the light fixture in place. The electrical outlet box is provided with a face plate which presents the electrical contacts in combination with lug portions. The light fixture includes mating lug portions which on rotation clip into and secure the light fixture in place on the face plate. The lug portions on the light fixture also include electrical contacts which lead to the lamp of the fixture. Hence when the lug portions are engaged to support the light fixture, the electrical contacts engage to complete the circuit. The drawback with this system is that, due to the inter-relationship of the lugs and the electrical contacts, there is a limitation on the amount of support that can be provided in the lug systems while continuing to provide suitable engagement of the electrical contacts. Furthermore, the electrical contacts are left exposed thereby presenting potential hazard in mounting the light fixture in place or allowing the user to reach up into the outlet of the face portion and contact one or more of the live electrical leads.
Canadian patent No. 1,040,606 also suffers from the disadvantage of the prior art U.S. patents in that it cannot be universally applied to connecting a wide variety of fixtures. For example, FIGS. 1 and 2 of the prior art Canadian patent illustrate that a central threaded tubular rod is mounted to the coupling as a central tubular rod connector. The threaded tubular rod is relatively short and is designed to hold the cover plate in position and to provide a thread to attach a ring (or hook) upon which a light fixture or chain is hung. The disclosure describes use of the ring (or hook) in terms which are specific to the application of hanging a light fixture or chain therefrom.
In summary, prior art coupling devices suffer from the disadvantages that they protrude significantly into the electrical junction box; they are of complex design; and installation of the fixtures is typically complex (i.e. requiring two or more steps).
SUMMARY OF THE INVENTION
An electrical coupling device for detachably securing a fixture to an electrical connector box in accordance with an aspect of the present invention comprises male and female interconnecting components. The fixture is connected to the male component where the male component is secured to the female component by rotating one component relative to the other. The female component has a plurality of catches. The male component has a plurality of studs for insertion and engagement with the catches by way of rotational movement of the studs into the catches. The catches are spaced apart in a circular array at a first radius relative to the center of rotation of the components. The improvement comprises:
(1) at least two spaced-apart female resilient clips of electrically conductive metal, the clips are located in a circular pattern at a second radius on the female component;
(2) the male component has at least two spaced-apart contacts of electrically conductive metal, the contacts being located in a circular pattern at the second radius;
(3) the male contacts are in register with the clips when the studs are in register with the catches.
Rotation of the male component to engage the studs with the catches simultaneously engages the contacts with the clips to depress the clips slightly to ensure electrical contact.
According to the present invention, an electrical coupling device is provided which does not significantly protrude into the electrical outlet box or ceiling as in the aforementioned prior art devices. The device of the present invention requires a simple rotation to attach and detach a light fixture that has an appropriate connector. The device is applicable to a wide range of light fixture types and electrical box sizes, and can be directly mounted to a building surface, without an electrical junction box, and without protrusion into the wall or ceiling.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention are shown in the drawings, wherein:
FIG. 1 is an exploded perspective view from above of the electrical fixture coupling according to an aspect of this invention;
FIG. 2 is an exploded perspective view of the electrical fixture coupling of FIG. 1 from the underside;
FIG. 3 is a section through the male and female components of the coupling prior to assembly;
FIG. 4 is a section through the assembled coupling;
FIG. 4A is a section view along the lines 4A--4A in FIG. 4;
FIG. 5 is a combined half-section and exploded view of a bolt mounted fixture according to a first alternative embodiment of the present invention;
FIG. 6 is a combined half-section and exploded view of a modified bolt mounted fixture according to a second alternative embodiment of the present invention;
FIG. 7 is an exploded perspective view of a central tubular spacer ring for the bolt mounted fixture of FIGS. 5 and 6;
FIG. 8 is an exploded perspective view of tubular rod spacer rings for the bolt mounted fixtures of FIGS. 5 and 6;
FIG. 9 is an exploded sectional view of a central tubular rod mounted fixture according to a third alternative embodiment of the present invention;
FIG. 10 is an exploded sectional view of a hanging cord lamp fixture mounted according to a fourth alternative embodiment of the present invention; and
FIG. 11 is an exploded sectional view of a hanging chain lamp fixture mounted according to a fifth alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
It is appreciated that a variety of electrical outlet boxes and fixtures are available in the marketplace. For purposes of discussion of this invention and demonstration of its principles, specific reference will be made to a well known type of outlet box and fixture constructions. It is, of course, appreciated that the principles of the invention would, however, apply to any other type of readily available fixture and electrical outlet. With reference to FIGS. 1 and 2, the electrical fixture coupling device 10 comprises male and female components 14 and 12. The female component 12 is secured within or to a standard type of octagonal shaped electrical outlet box 16. Wiring 18 is fed through a cable shield 20 which may be of flex link metal and through the inlet coupling 22 of the outlet box 16. The three electrical leads 24, 26 and 28 of the standard 110 volt wiring system are coupled to the corresponding terminals 30, 32 and 34. In accordance with standard practice, two of the leads, for example 26 and 28, will be positive and negative leads, whereas lead 24 is the common ground. Each terminal 30, 32 and 34 is surrounded by a raised ridge portion 36, 38 and 40. The raised ridge serves to contain the looped end portion of the respective electrical wire lead and captured in place during connection of the leads to the terminals.
It is also possible to friction fit the contact terminals 30, 32 and 34 (see for example, FIG. 4A) and to have a self attaching connector in which electrical wires 24, 26 and 28 are pushed into a hole (not shown) in which electrical contact is made and the wires are secured. The preferred push connector of FIG. 4A is characterized by significant advantages over prior art push connectors common on existing switches and receptacles.
The male component 14 has an electrical wire 42 which is connected to a light fixture or the like extending through a decorative dished-shaped exterior plate 44 and through an aperture 46 of the male component 14 and into the chamber generally designated 48. There are three electrical wires of the incoming light fixture wire 42 which are designated 50, 52 and 54. The wires are respectively secured to the electrical terminals 56, 58 and 60. As with the terminals of the female component 12, the terminals 56, 58 and 60 are surrounded by a raised ridge portion 62, 64 and 66. This assists in assembly and connection of the electrical wires to the terminals to capture them in place. Each of the terminals 56, 58 and 60 include outwardly extending contacts 68, 70 and 72. These male contacts engage corresponding female contacts of the female component 12, as will be discussed with respect to FIGS. 2, 3 and 4.
The male component 14 includes elongate recesses 74 and 76 which receive nut and bolt combinations for connecting decorative plates, such as plate 44, and for securing the light fixture to the male component 14. For example, self tapping screws 8 or bolts may be extended through the elongate recesses 74 and 76 and threaded into apertures 78 and 80 of lugs 82 and 84 to secure the attachment plate 14 in position, as described in greater detail below with reference to FIGS. 5, 6 and 8. Each recess 74 and 76 is surrounded by a suitable ridge 86 and 88 to enclose the respective bolt head.
In order to prevent accidental dislodgement, a locking device is incorporated into the female component 12 in the form of small domed protrusions or dimples 79 and 81 which are designed to slide over the surfaces of winged recesses 74 and 76 of male component 14 when the male component 14 is being rotated clockwise relative to female component 12 for connecting the male and female components. However, the dimples 79 and 81 abut the winged recesses 74 and 76 when the male component is rotated into connection with the female component, thereby effectively preventing inadvertent counterclockwise rotation of the male component 14 relative to the female component 12 without the application of a reasonable amount of torque.
As shown in FIG. 2, the female component 12 is secured to the electrical outlet box 16 by use of bolts 90 and 92. The bolts extend through apertures 94 and 96 and are threaded into the threaded apertures 98 and 100 of the outlet box lugs 102 and 104. Alternatively, the bolts may extend through slotted apertures 95 and 97 for smaller sized electrical boxes. The secured position of the female component 12 in the electrical outlet box 16 is shown in FIG. 4. Provided on the upper surface 13 of the female component 12 is a ridge 15 which defines an octagonal shape which corresponds to the inner dimensions of a standard octagonal electrical outlet box 16. The raised ridge 15 correctly locates the base plate bolt holes 94 and 96 with the bolt holes 98 and 100 on the lugs 102 and 104 of the electrical box 16. This ensures a secure fitment of the female component 12 to position the component in the electrical outlet box 16. The circular disk, or flange 99, outside the octagon shaped ridge 15 extends beyond the dimensions of the electrical box and thereby ensures that the component 12 fits flush to a wall or ceiling even though the outlet box may be recessed or misaligned.
In some installations an electrical box is not required to house the electrical household wiring for the lamp fixture. In such cases, the female component 12 includes a further ridge 17 for providing clearance for the electrical wiring extending between the female component 12 and the ceiling. The overall dimensions of male component 14 and female component 12 can be reduced in such an installation.
The underside 106 of the female component 12 (FIG. 2), which constitutes the face plate of the electrical outlet box, includes two sets of semicircular ring portions generally designated 108, 110, 112 and 114. Ring set 108 and 110 include a plurality of catches, the entrance to which are defined by the respective recesses 116, 118, 120 and 122. The inner set of rings 112 and 114 include the female resilient clips of electrically conductive metal. The entrance to those clips is defined by recesses 124, 126 and 128. The clips are recessed so as to conceal live electrical parts.
The male component 14 includes on an outer ring set 130 and 132 the outwardly projecting stud portions 134, 136, 138 and 140. As already noted, on the inner ring portion, as defined by circular edge 142, outwardly extending male contacts 68, 70 and 72 are provided. The male component is provided with an integrally molded arrow 144 which, when aligned with the indented arrow 146 of the female component, automatically aligns the studs 134, 136, 138 and 140 with the recesses 116, 118, 120 and 122. Also, the electrical contacts 68, 70 and 72 are aligned with the recesses 124, 126 and 128.
To assemble the male component 14 to the female component 12 with the arrows 144 and 146 aligned, the male component 14 is rotated in the direction of arrow (clockwise) 148 to engage the studs with the catches. As shown in FIG. 3, the studs are defined by the lugs 136 and 138 which are of inverted L-shape to define undercut portions 150 and 152. The catches of the female component 12 are defined by the depending ledges 154 and 156 to define supporting surface 158 and 160. To support the male component, when engaged with the female component, the faces 150 and 152 rest on and are engaged with the faces 158 and 160 to support the light fixture in a manner to be discussed with respect to FIG. 4. The terminals 30 and 32 include resilient clips 162 and 164. As shown in the section of FIG. 4A, clips are J-shaped as protected by face portions 166 and 168 of the respective ring portion 112 and 114. The ledges 166 and 168 in covering the clips 162 and 164 prevent the user from engaging the clips with their fingers or various tools, such as screwdrivers, and hence substantially reduce the risk of electric shock during installation.
The J-shaped clips 162 and push connectors 163 are secured to the female component at the raised block portion 170 by way of the terminal screw or rivet 172. Hence a cantilever mounting of the J-shaped clip 162 is provided with a flexible distal portion 174. Multistrand wire may be inserted between clip 162 and push connector 163 which yields under bending pressure. The connector 163 then clamps down on the wire and secures the wire in place with a contact area extending fully around the arcuate portion of connector 163. The push connector arrangement of FIG. 4A may also be advantageously used for the terminals 58 and 32. When the male contact portion 72 abuts the sloping portion 174 during rotation of the male component relative to the female component, the distal portion 174 is pushed upwardly by the male contact 72 to ensure secure electrical contact between the male and female components. A similar action occurs with respect to the other electrical clips of the female component which occurs at the same time as the stud components of the male couplings 68 and 70 engage the associated catches of the female components (e.g. 162 and 164). As a result the assembled unit, as shown in FIG. 4, has the studs 134, 136, 138 and 140 engaged with the respective supporting ledges as exemplified in FIG. 4 as 154 and 156. The male contacts 70 and 72 engage the respective clips 162 and 164, thereby effecting a hanging cord lamp fixture connection as shown in FIGS. 10A and B. As discussed above, the electrical cord 42 is secured by means of a cord restrainer 1004. The restrainer effectively transfers the weight of the fixture to the flange 180 surrounding the aperture 46 of male component 14, and thereby to the female component 12 through the male component 14 via the support lugs 134, 136, 138 and 140 engaging the corresponding catches of the female component. No stress is applied to the electrical contacts 70 and 72. Hence the design of the lugs and catches of the male and female components is independent of the electrical contacts to thereby support any desired weight of the light fixture without interfering with the electrical contacts. In this way, the electrical contacts resiliently urge the clips upwardly to ensure continued electrical contact of the light fixture to the power source in incoming line 18.
As shown in FIG. 4, the male component 14 has extending outwardly of the stud portions a plate extremity 182, 184 for supporting the two-bolt fixture of FIGS. 5 and 6 via apertures 74 and 76. As discussed above, when the unit is assembled, the female component 12 is flush against the face of the finishing material for the wall or ceiling to complete the assembly and provide a flush mount of the light fixture, and the cover plate 44 extends so as to cover the entire connector and fit flush with the wall or ceiling.
The male and female components of the coupling device are attached by means of the separate interengaging studs and catch portions. The system has been designed for close tolerances to achieve a secure and strong connection between the components. Once locked the components have a very low profile for preventing the female component 12 from intruding into the outlet box, and to ensure that the device remains inconspicuous when the male component 14 is not attached. The components of the device may be injection molded of suitable plastic resin. The plastic resin may include flame retardant, heat resistant, creep resistant additives. A suitable plastic may be that of acrylonitrile butadiene styrene composition.
In addition to the light fixture mountings illustrated in FIGS. 1-4, additional mountings are contemplated within the terms of the present invention, as follows:
bolt mounted fixtures (FIGS. 5 and 6);
central tubular rod mounted fixtures (FIG. 9);
hanging cord lamp fixtures (FIG. 10);
hanging chain lamp fixtures (FIG. 11); and
integrally molded fixtures (not illustrated).
Turning to FIG. 5, a combined half-section and exploded view is provided of a bolt mounted fixture according to a first alternative embodiment mounted in the form of a retrofit. An ordinary two-bolt light fixture is mounted on the male component 14 by means of a pair of bolts 500 and 502 inserted through apertures 76 and 74, and secured by means of lock nuts 504 and 506, spacer nuts 508 and 510, and decorative nuts 512 and 514. The height of the cover plate 44 is determined by adjustment of spacer nuts 508 and 510. The bolts 500 and 502 are maintained in a correct width position within slots 74 and 76 by means of lock nuts 504 and 506. The cover plate 44 is secured to the bolts 500 and 502 by means of nuts 512 and 514, respectively.
A modified light fixture is illustrated with reference to FIG. 6. Manufacture installed mounting lugs 600 and 602 are provided with holes 604 and 606 through which a pair of self-taping screws 608 and 610 may be inserted, via holes 76 and 74 of the male component 14. The mounting lugs are installed at an appropriate height for correct positioning of the male component attachment plate 14 relative to the female component base plate 12.
Correct spacing between the male component 14 and the associated bolt mounted light fixture can also be realized by employing either central tubular spacer rings or tubular rod spacer rings as shown in FIGS. 7 and 8, respectively. According to FIG. 7, a central tube spacer ring 700 is mounted via a friction fit over the raised circular portion 702 of the male component 14. The spacer ring 700 can be constructed to various heights for achieving selective spacing of the cover plate 44 relative to the male component 14. FIG. 8 shows a pair of tubular rod spacers 800 which can be manufactured to predetermined heights to achieve selective spacing of the cover plate 44 relative to the male component 14. A pair of bolts 500 and 502 are inserted through the apertures 74, 76 of the component 14 and through the tubular rod spacers 800. A pair of decorative nuts 512 and 514 are fastened to the bolts 500 and 502 which protrude to respective apertures in the cover plate 44.
Traditional central tubular rod mounted fixtures are screwed into a cross bar that is bolted to the electrical outlet box. However, according to the embodiment of FIG. 9, the base plate or female component 12 is substituted for the cross bar of traditional installations, and the tubular rod 900 of the fixture is held in place by a pair of nuts 902 and 904 which lock the centrally mounted fixture in position. A cover plate (not shown) is then fastened to the central tubular rod 900 by means of a radially oriented screw, in a well known manner. The electrical wiring 42 runs through the tubular rod 900 and is connected to the attachment plate or male component 14 by means of electrical connector bolts or screws 56, 58 and 60 (FIG. 1). A cover plate 44 (FIG. 1 and 2) is attached to the central tubular rod 900 in the traditional fashion
FIG. 10A illustrates a hanging cord fixture embodiment of the present invention in which a flexible electrical cord 42 extends from a lamp shade 1002 through an aperture 46 in the male component 14 which is held in place with a cord restrainer 1004 shown in detail with reference to FIG. 10B. The cord restrainer 1004 slides along the electrical cord 42 for adjusting the height of the lamp and the length of wiring which extends to the electrical contacts on the male component 14. The cord restrainer 1004 fits into and is compressed by the aperture 46 which restrains movement of the cord. A cover plate 44 is shown in FIG. 10A attached via a friction fit over the raised circular portion 702 of the male component 14.
FIG. 11 shows a hanging chain fixture according to another alternative embodiment of the present invention, wherein chain links 1100 are supported by a hook 1102 having a central threaded aperture for receiving a threaded tubular rod 1104. A pair of lock nuts 1106 connect the tubular rod 1104 to the male component 14. The hook 1102 is threaded onto the tubular rod 1104 for supporting the fixture connected at a remote end of chain 1100 and to hold the cover plate 44 to the building surface. The electrical cords 50 and 52 twine through the chain links 1100 in a well known manner.
Additionally, the attachment plate or male component 14 may be directly injection molded with a lamp fixture base to produce an integral unit (not shown). In such a case, only the central portion of the male component 14 is utilized. The elongated recesses 74 and 76 would not be used. Also, the electrical cord 46 is substituted with a direct electrical connection from the contacts 68, 70, 72 to the light bulb socket or sockets.
Although preferred embodiments of the invention have been described herein in detail, it will be understood by those skilled in the art that variations may be made thereto without departing from the spirit of the invention or the scope of the appended claims. | An electrical coupling device for detachably securing a fixture to an electrical outlet box comprises male and female interconnecting components. The fixture is connected to the male component where the male component is secured to the female component by rotating the male component. The male component has a plurality of catches. The male has a plurality of studs for insertion and engagement with the catches by way of rotational movement of the studs into the catches. The catches are spaced apart in a circular array at a first radius. The improvement comprises at least two spaced apart female resilient clips of electrically conductive metal. The clips are located in a circular pattern at a second radius on the female component. The male component has at least two spaced-apart contacts of electically conductive metal. The contacts are located in a circular pattern at the second radius. The male contacts are in register with the clips when the studs are in register with catches. Rotation of the male component to engage the studs with the catches simultaneously engages the contacts with the clips to depress the clip slightly to ensure electrical contact. The electrical coupling device is characterized by minimal protrusion into the electrical junction box; direct mounting by means of a simple one-step rotation; and applicability to a wide range of fixtures junction boxes; and direct mounting without the requirement of a junction box. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
The present application is a divisional of U.S. patent application Ser. No. 10/895,007 filed Jul. 20, 2004 now U.S. Pat. No. 7,443,888, and U.S. patent application Ser. No. 10/895,007 is related to, and claims the benefit of U.S. Provisional Application No. 60/508,000, filed on Oct. 2, 2003, the contents of each are herein incorporated by reference.
FIELD OF THE INVENTION
This application relates to data transport arrangements that allow a provider to support any client data protocol, as well as provide quality of service monitoring that is ascertainable without delving into the client's signal. More particularly, this application relates to an arrangement that, for example, allows a subwavelength SONET client signal to be transported transparently and with sufficiently high fidelity so that inherent timing information of the signal is maintained.
BACKGROUND OF THE INVENTION
A transport provider that wishes to offer high capacity facilities to customers can implement the offer by simply providing so-called “dark fiber,” allowing the customers to place whatever signals they wish on the fiber.
One value proposition is for the provider to offer a fiber and a “service,” whereby a channel is provided for transmission of information, with a guarantee that the transmitted information will arrive at its destination with an agreed-to quality of service. To provide the agreed-to quality of service, the provider sends the information over the fiber in a particular protocol that is chosen by the provider, monitors the quality of the service, and performs appropriate maintenance activities, as needed. That means that the provider carries on the fiber various signals that do not belong to the customer for the purpose of monitoring the quality of service. Dark fiber clearly cannot meet this value proposition.
An advanced value proposition is for the provider to offer a fiber, and to also offer a plurality of channels, concurrently, using a particular protocol, with the channels adapted to carry client signals. SONET is an example of such a value proposition. SONET encapsulates a client-provided signal into successive Synchronous Payload Envelope (SPE) blocks of data, injects these blocks into successive SONET frames, modulates numerous SONET frames onto different wavelengths, and places them onto a fiber. The reverse process takes place when data needs to be extracted.
One aspect of SONET is that it offers clients a variety of bandwidths. The lowest SONET bandwidth (OC-1) is capable of carrying a DS3 signal, having a 44,736 Mb/s rate, and the SONET standard contemplates higher bandwidths in multiples of OC-1. However, commercial equipment that carries SONET signals over fiber handles only OC-3, OC-12, OC-48, and OC-192 signals. Intermediate rates are generally multiplexed into one of these four signal rates.
Another aspect of SONET is that it can be add/drop multiplexed, meaning that a given channel can be extracted from, or added to, the information signal that is contained in a given wavelength without having to extract all of the other channels that are contained in the information signal, or to reconstitute the information signal.
Still another aspect of SONET is that it carries it's own maintenance information, permitting the provider to offer a guaranteed level of service quality without having to delve into the client's signal per se.
What would be desirable that SONET cannot provide is the ability to transmit client signals that themselves are SONET frames, transparently, and in a bandwidth efficient manner while maintaining the timing integrity of the client SONET signals themselves. By “transparently” what is meant is that the offered client's signal (e.g., an OC-3 SONET signal) can be communicated through the network, from an ingress node to an egress node, in a manner that allows the client's signal to be multiplexed onto a fiber with one or more other signals, where the other signals possibly have different bandwidths, or different protocols, and where the other signals may be time-division-multiplexed onto the same wavelength, or onto different wavelengths, the clients signal can have any desired protocol (i.e., including SONET), the client's signal can be add/drop multiplexed at any point in the network without requiring add/drop operations on other signals and, correspondingly, add/drop operations need not be undertaken relative to the client's signals when add/drop multiplexing is performed on some other signal on the fiber, and the provider is able to ascertain quality of service provided to the client without having to look into the client's signal per se.
As indicated above, SONET fulfills the above transparency requirements, except that it does not allow the client to send a signal that itself follows the SONET protocol while maintaining the timing integrity of the SONET client signal. Clearly, for example, one cannot send an OC-3 SONET client data frame as a unit over an OC-3 SONET frame, because the payload bandwidth of the provider's OC-3 frames is simply not large enough to carry both the payload and the overhead of the client's signal. One possibility that has been studied by Lucent Technologies is to stuff an OC-3 frame into an OC-4 signal. After extensive efforts it was concluded that this proposal was not able to meet the SONET timing standards for the client SONET signal. This is clearly evident in FIG. 5-18( a ) of T1X1.3/2002-036 contribution to the T1 Standard Project-T1X1.3. This contribution, titled “Jitter and Wander Accumulation for SONET/SDH over SONET/SDJ (SoS) Transport” by Geoffrey Garner, dated Sep. 30, 2002, which is hereby incorporated by reference. Note that all simulation depicted in the aforementioned FIG. 5-18( a ) are above the OCN Reference Mask; where the need is to be below this mask.
Separately, the Digital Wrapper standard exists (G.709) that contemplates signals flowing in frames having one of three line rates. The lowest rate (OTU1) carries 20,420 frames/s, and each frame consists of 16,320 bytes that structurally can be viewed as 4 rows and 4080 columns. Sixteen columns are devoted to overhead, 3808 columns are devoted to client payload, and 256 columns are devoted to forward error correction, which results in a payload rate of approximately 2.666 Gb/s. The OTU1 rate can be used to communicate a 2.48832 Gb/s OC-48 SONET signal, as the payload area was sized for that capacity. Equipment exists to terminate a number of SONET signals and, after removing their payload information (SPE), multiplex the individual payloads to form an OC-48 signal, to encapsulate it in an OTU1 digital wrapper, and to modulate the resulting signal onto a chosen wavelength. To date, however, no design exists for channelizing the Digital Wrapper for the many lower rate data services that a telecommunications carrier is called upon to transport, such as the above-mentioned OC-3 signal, i.e., a design that allows one to carry sub-multiples of the OTU1 signal (also termed sub-wavelength channels) using the Digital Wrapper standard.
BRIEF SUMMARY OF THE INVENTION
An advance in the art is realized by extending the Digital Wrapper standard G.709 to create a tributary group from OTU1 16 frames forming a tributary group. This group this group is mapped onto a grouping of 64 OTN tributary frames that are di-byte interleaved. Each tributary frame thus can be viewed as a block of 15240 columns and 4 rows, where the first 4-column section is devoted to overhead. The remaining columns are devoted to payload data, with the fourth row of the overhead section assigned to negative pointer justification opportunities, and the following four bytes (in columns 5th through 8th) are assigned to positive pointer justification opportunities. The payload data section is able to hold OPVC1 frames, each of which has an overhead section, and preassigned negative and positive justification byte positions.
With the extended Digital Wrapper protocol, which seamlessly dovetails with the G.709 standard, data that entered an ingress node is synchronized to the local clock and a phase offset measure is developed and included in the transmitted signal. This measure is evaluated repeatedly, for example, every OPVC1 frame. At an egress node, the phase-offset measure that is received with the signal is employed to derive a more accurate client signal clock, and this enables the network to support client signals that need to be communicated with high clock fidelity, such as SONET signals.
Additionally, in order to minimize jitter and wander, pointer processing that is performed in each intermediary node through which a signal travels between the ingress and egress nodes is modified to introduce positive and negative justification bytes in excess of what is minimally necessary so as to shift energy into higher frequencies that can be filtered out by the phase lock loop at the egress node.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated and described herein with reference to the various drawings, in which like reference numbers denote like method steps and/or system components, respectively, and in which:
FIGS. 1A and 1B depict a tributary frame in accord with the principles disclosed, and an OPVC1 frame that is injected payload of the tributary frame;
FIG. 2 is a block diagram showing selected aspects of an ingress node in accordance with the principles disclosed herein;
FIG. 3 is a block diagram showing selected aspects of an egress node that complements the ingress node of FIG. 2 ;
FIG. 4 is a block diagram of a node through which a signal traverses between the ingress node and the egress node; and
FIG. 5 shows the circuit arrangement that performs modified pointer processing.
DETAILED DESCRIPTION OF THE INVENTION
To gain an appreciation for the disclosed advance, it is beneficial to review the timing problems that arise in the SONET network in spite of the fact that all nodes in a SONET network nominally operate off a common clock. There are two specific timing problems of interest: timing impairments as a result of mapping the client signal into the SONET frame, and timing impairments resulting from SONET pointer processing. Each of these will be discussed separately.
SONET employs a layered structure, with one layer concerning itself with framing, and another with the payload being carried. As for the framing layer, a SONET STS-1 signal consists of a sequence of frames each containing 810 bytes that can be viewed as a 90 column by a 9 row arrangement, where the first three columns contain transport overhead byes. Of the 27 available header bytes, 9 bytes (the three transport overhead bytes of the first three rows) are devoted for Section Overhead, and 18 bytes are devoted for Line Overhead. The remaining 87 columns make up the STS-1 envelope capacity, which contains the synchronous payload envelope (SPE). The first column of the SPE is devoted to Path Overhead, and two columns (columns 30 and 59) are devoted to “fixed stuff”. This leaves 756 bytes in the SPE for client data, which is sufficient for mapping a DS3 client data signal.
The SPE can be placed into the STS-1 envelope capacity beginning at any byte position within the STS-1 envelope capacity. The location of the first byte of the SPE (which is called the J1 byte) is identified by a pointer that is contained in the first two bytes of the Line Overhead (H1 and H2 bytes) of the STS-1 frame.
A SONET client's input data that enters a SONET ingress node (e.g., node A) is mapped into the SPE using conventional buffering techniques. That is, client's data is written into a buffer memory at the client's clock frequency, and is outputted from the buffer memory at the ingress node's clock frequency. The read-out clock frequency, on the average, ought to be the same as the write-in clock, so as not to cause an overflow or underflow. In order to prevent a possible underflow of the buffer when the read-in clock is consistently slower, the read-out operation is stalled (no data is read) at prespecified points of the SPE, as necessary. In order to prevent overflow when the clock situation is reversed, data is read out at times within the SPE that normally are not used for reading out data. A SONET frame is then created (having a fixed number of data bytes) by inserting the SPEs into the SONET frames as indicated above, using the pointer to identify where the SPE begins, and once the SONET frame is created, it can be sent out, for example, to node B.
It is important to note that these operations (stalling the reading out process and/or reading out extra data) introduce phase jumps in the mapped data stream, which cause timing impairments in a recovered client signal. We refer to this as mapping impairments.
Considering what happens at node B, it is possible that the frequency of the node B clock might be slightly different from that of the node A clock even though the intent of the SONET network is for all nodes to operate off a common clock (this can occur during timing reference failures or due to the introduction of noise into the timing signals). Because of this possibility and because of normal propagation delays in the signal flows throughout the network, node B must perform at least the following steps:
1. derive an approximation of the node A clock, y A , from the incoming signal,
2. using clock y A , extract the header information that is within the incoming frame,
3. using clock y A , extract the payload information that is within the incoming frame,
4. process the extracted header information and react to it,
5. using clock y B , create new header information for an outgoing frame,
6. using clock y B , inject the extracted payload, into the outgoing frame, and
7. send out the newly created frame (at clock rate y B ).
Of the above steps, step 6 is the most challenging, because of the asynchrony between the clocks, y A , and y B . The task is to create an SPE that is to be inserted into a node B SONET frame, which operates at rate y B , and to do so from data that is received from node A at frequency y A . If y B > y A (even a little) the data arrives more slowly than it leaves, and a consequence of this is that every so often the outputting of actual data must be arrested because there is no data to output. Since the node's output is at a constant clock rate (y B ), during a clock period when there is no data, the system must simply wait and, effectively output a dummy data byte. In order to avoid having to output dummy bytes whenever a no-data condition exists, a buffer is included that, though it introduces delay, affords the flexibility to place dummy bytes in pre-specified overhead positions (the byte position immediately following lie H3 byte of the Line Overhead). Since the SONET frames that are created by node B are outputted at a fixed rate, the insertion of a dummy byte in an SPE shifts the positioning of the following SPE forward within each SONET frame. To remain aware of the positioning of the SPE starting point, the pointer in the SONET frame's overhead is adjusted (incremented) to specify where the starting point of the SPE is.
Correspondingly, if y B < y A , the data arrives more quickly than it leaves, and a consequence of this is that, though the arriving data can be buffered, eventually all of it must be placed within an outgoing SPE, in some otherwise unused byte position, or else an overflow condition would occur. That means that an SPE, or at least the SONET frame, must have such an unused byte position. Indeed, the SONET design includes a byte in the header (the H3 byte) that can be so used. Thus, when y B < y A , every so often (depending on the size of the difference between y B and y A ) a data byte must be stuffed into the available byte position that does not normally carry client data (H3 byte). Consequently, the SPE ends at one position sooner than it would otherwise, and the next SPE's J1 byte is stored one position sooner as well. Correspondingly, the pointer is decremented to correctly specify the SPE's starting point.
All of this shifting of SPE's, inserting dummy bytes, and/or inserting extra data bytes is carried out with what is typically referred to as “pointer processing.” A side effect of the pointer processing, or more specifically of the addition of dummy bytes or extra data bytes, that results from the asynchrony between clock y A and y B is that the number of actual client bytes in an SPE differs from frame to frame creating phase jumps, and client signal tiring impairments are thus introduced. In addition, as each node performs its own pointer processing functions, asynchronously of all other nodes, pointer adjustment decisions may be made at the same time in successive nodes, causing an accumulation of error.
If the clients data were to be extracted at node B, i.e., if node B were the egress node, it would be quite simple to extract the SPEs based on knowledge of their starting points (provided by the pointer), extract the overhead bytes of the SPEs, identify the dummy bytes and stuffed bytes from apriori information about the nature of the input signal (i.e., number and location of the “fixed stuff” columns) and from the pointer, and output the extracted client data as it is unmapped from the SPE. This unmapping yields the client's signals, but at an irregular rate. There is a hiatus during the 27 transport overhead bytes (that, on occasion, may include a data bye in H3), a hiatus during the 9 path overhead bytes, a hiatus during (at least some of) the 18 fixed stuff bytes (from columns 30 and 59), and a hiatus during the inserted dummy bytes. The client, however, desires its data to be provided by the egress node at a constant rate, and desirably, at the rate at which the data was offered to the ingress node. In addition, the client signal could conceivably traverse multiple SONET networks (due, for example, to the fact that a service may need to be carried via multiple service providers in order to be transmitted end-to-end, i.e., from a local exchange carrier (LEC) to an inter-exchange carrier (IXC) to another LEC). Thus, multiple segments that each have pointer processing, and possibly mapping and unmapping, may be cascaded and the timing impairments introduced by each segment would accumulate, giving rise to a client signal whose clock is impaired. The timing impairments produced by these operations make it impossible to use a received client signal (i.e., that signal derived from the SPE) that is a SONET signal which is used as a source of timing for another SONET network.
Refocusing on the objective of offering a facility to transport client data of any protocol transparently, including SONET, in order to compensate for the above effects in the SONET network, in accord with the principles disclosed herein a different transport protocol is used, to wit, the Digital Wrapper standard G.709, which happens to be very similar to SONET, but is flexible enough to permit including a number of unique and novel features in the network's nodes that are not defined for current or next generation SONET equipment. These functions, which do not exist in current generation equipment, and are not defined for next generation Digital Wrapper or SONET equipment, are compensation for the timing impairments introduced end-to-end by the client signal mapping and unmapping process, and node-to-node compensation for the timing impairments introduced by the pointer adjustments received from the previous node.
The compensation for end-to-end timing impairments introduced due to client signal mapping and unmapping functions is addressed through the use of phase-offset information that is derived from the phase difference between the ingress client clock and the ingress node system clock. The phase-offset information is transported end-to-end with the data signal and is used to compensate the egress client clock derived from the outgoing client data stream. This eliminates most of the client egress clock timing error due to mapping unmapping functions.
The compensation for node-to-node timing impairments introduced due to pointer processing is addressed through the use of a pointer filter in conjunction with an adaptive pointer generator that filters upstream pointers generated by previous nodes and adaptively generates its own pointers in a manner that allows downstream filters to remove their effects in succeeding nodes. This advanced pointer processor is described in more detail later.
In accord with an embodiment disclosed herein, the low rate of the Digital Wrapper standard G.709, i.e., OTU1, is used as the underlying network transport mechanism, which carries data in frames running at the rate of approximately 20,420 frames/sec. To provide for the sub-wavelength channels, i.e., for the transporting of signals lower than the SONET OC-48 signals, in accord with the principles disclosed herein an extension to the G.709 Digital Wrapper standard is provided. The extension takes 64 consecutive OTU1 frames, where each frame having 14 columns of overhead at the beginning of each frame, and combines the payload (3808 columns) and payload overhead (2 columns) areas into a very large frame (243,840 columns). Within that very large frame the columns are divided to create 16 frames (also referred to herein as OPTU1 frames, or communication layer frames), that are time division multiplexed and di-byte interleaved timeslots, by assigning the first two columns of the large frame assigned to timeslot # 1 , the second two columns to timeslot # 2 , etc. through to the 16.sup.th timeslot, and then repeating the assignments until all columns of the large frame are assigned, thereby attaining effectively communication layer frames having 15,240 columns each. This frame is illustrated in FIG. 1A . Each OPTU1 frame has four columns of overhead and 15,236 columns of timeslot envelope capacity (similar to STS-1 envelope capacity). The four columns of overhead (OVHD) contain pointer information (which controls the operation of an advanced pointer processor to be described later) in the first three rows of the frame and 4 stuff byte positions (negative justification opportunity bytes NJO)) in the fourth row of the frame. The remaining 15,236 columns constitute the envelope capacity, which includes 4 potential dummy byte positions (positive justification opportunity bytes (PJO)) next to the 4 stuff byte positions in the fourth row of the frame. In such an arrangement, the payload envelope is a frame (herein referred to as an OPVC1 frame, or framing layer frame) that is not unlike the SONET's SPE, which frame contains four columns of timeslot path overhead and 15,232 columns of payload data (into which the client signal is mapped). This is illustrated in FIG. 1B . The overhead bytes of the fourth row are reserved for negative justification bytes, and the four bytes in the fourth row that follow the negative justification bytes are reserved for positive justification bytes. The path overhead includes 10 bits reserved for phase-offset information, and two mapping justification bits (JC). A JC value of 00 means that no dummy bytes were inserted and no extra bytes were stuffed, a JC value of 01 means that four data bytes were inserted, and a JC value of 11 means that four dummy bytes were stuffed.
The 15232 columns of payload data can exactly contain an OC-3 signal as long as the OPVC1 and OC-3 clock are running at their nominal rates.
As the above-described structure suggests, one of the similarities between the Digital Wrapper standard, as extended, and SONET is that both employ the layered structure, where one layer concerns itself with framing (placing the client's data into frames) and another layer concerns itself with the payload being carried. One significant difference between SONET and the Digital Wrapper standard is that the former is synchronous, whereas the latter is asynchronous. That is, although all of the nodes' clocks of a network employing the Digital Wrapper standard are close to each other (within +/−40 ppm of each other), there is no requirement that they must be the same.
Thus, in accord with the principles disclosed herein, a client's signal at an ingress node (node A) has to be mapped into the payload area of an OPVC1 frame, with dummy bytes (positive justification), or extra data bytes stuffed (negative justification), as appropriate (as described above), as well as any residual phase-offset information that exists between the client signal clock and the node A clock, and the OPVC1 frame has to be placed into an OPTU1 time slot segment, with an appropriate pointer included in a header portion that points to the beginning of the OPVC1 frame.
FIG. 2 shows is a block diagram showing selected aspects of an ingress node in accordance with the principles disclosed above. Client data is applied to buffer 10 , and the client clock is applied to write address counter 11 . Under control of the client clock and address counter 11 client data is stored in buffer 10 (which is sometimes referred to as an elastic store). The line from counter 11 to buffer 10 includes both the address bits and the write command. The node's clock y A is applied to processor 14 , which gates the clock as necessary and applies the gated clock to read counter 12 . The output of counter 12 , which includes both the address bits and a read command, is applied to buffer 10 and, under influence of counter 12 , data is read out from buffer 10 and applied to processor 14 .
The clock gating performed by processor 14 accounts for the header bytes that need to be included in order to create OPVC1 frames, and the justification that needs to be undertaken because of the difference in clock rates between the client's clock and the node's clock. Negative justification is required when the client's clock is higher than nominal and, therefore, bytes need to be stuffed; positive justification is required when the client's clock is lower than nominal and, therefore, dummy bytes need to be inserted; or no justification is undertaken when neither stuffed bytes nor dummy bytes are called for.
Information about the need to justify comes from the read and write counters. Specifically, it is recognized that the difference between the read and write addresses should be bounded if no underflow or overflow should occur in buffer 10 , and it is beneficial to have that difference remain as constant as possible. Therefore, the addresses of write counter 11 and read counter 12 are applied to subtractor 13 , and the difference is applied to processor 14 . Based on that difference, processor 14 determines whether bytes need to be stuffed, dummy bytes need to be inserted, or neither task needs to be undertaken, and behaves appropriately, including creating the appropriate justification control (JC) bits.
The difference produced by subtractor 13 is also applied to sampler 16 . Illustratively, once per frame, just after a justification opportunity, the sampler samples the value of the difference that exists between the write counter 11 and the read counter 12 . This represents the residual phase-offset between the client clock and the gated system clock, and this difference is applied to processor 14 . The phase-offset information is written in to the frame overhead area and transported to the client egress de-mapper at the other end of the network, to be used to regenerate an accurate representation of a clock for the client's signal at the egress node.
The bytes received by processor 14 from buffer 10 based on the gated clock are then augmented with the appropriate JC bits, phase-offset information, and other overhead information, and formatted to create OPVC1 frames at the output of element 20 . These frames are applied to processor 15 , which creates OPTU1 frames.
Processor 15 injects OPTU1 overhead bytes into the created OPTU1 frames, determines where within the OPTU1 frame the created OPVC1 frames are to be inserted, generates and inserts an appropriate pointer that points to the beginning of the OPVC1 frame in the OPTU1 payload envelope, inserts the OPVC1 frame, and thus creates the OPTU1 frames at the output of processor 15 .
At the egress node, for example, node Z, the reverse of this process must be performed, that is, de-mapping of the client signal from the OPVC1 frame. An embodiment of this process is illustrated in FIG. 3 . In FIG. 3 , data originating from an upstream node is applied to clock recovery circuit 31 and to processor 32 . Circuit 31 recovers the clock of the previous node, and applies it to processor 32 . Processor 32 identifies the beginning of the OPTU1 frame, handles the OPTU1 overhead bytes, identifies the pointer, identifies the beginning of the OPVC1 frame, identifies and processes the justification control bits and the phase-offset information and creates a gapped clock that is applied to write counter 33 . This gapped clock is an approximation of the gapped clock generated by node A, the gated y A clock, during the mapping process. Under control of address and write commands that are applied by counter 33 to buffer 34 , the incoming client data is stored in buffer 34 .
Separately, address counter 35 that is advanced by variable control oscillator (VCO) 37 reads data out of buffer 34 . The address of counter 35 is subtracted from the address of counter 33 in element 38 , and the resulting difference is applied to low pass filter 36 . The output of low pass filter 36 controls VCO 37 .
The arrangement comprising elements 35 , 38 , 36 and 37 is a phase lock loop (PLL) arrangement that keeps the difference between counter 33 (which is advanced by the estimate of the gated y A clock) and counter 35 fairly stable. This is a mirror image of the feedback arrangement found in FIG. 2 , which keeps the difference between counters 11 and 12 fairly stable, where counter 12 is advanced by clock y A . Consequently, the data read out of buffer 34 is fairly close in frequency to the clients data arriving at node A.
If not dealt with, the two impairments discussed earlier, end-to-end mapping impairments and node-to-node pointer processing impairments, will corrupt the quality of the client timing information so as to make it unusable as a timing reference. The amelioration of the node-to-node pointer processing impairments will be discussed below, however the end-to-end mapping will be discussed here. The justification operations performed by the mapping function in node A are essentially controlled by the difference in frequency between the incoming client clock and the OPVC1 clock derived from the node A system clock. If the derived OPVC1 clock is running at a rate that allows the client signal to be almost exactly matched to the OPVC1 payload rate then justification operations will be very infrequent. This creates phase jumps in the client signal data that occur at a very slow rate producing significant low frequency components. The de-mapper at node Z contains the low pass filter 36 that can filter some of this noise, however the cutoff frequency cannot be made arbitrarily low. Therefore, whatever cutoff frequency is specified, a difference between OPVC1 clock and client clock can be determined that will produce low frequency components below the cutoff frequency of the de-mapper filter thus corrupting the client timing. The phase-offset information is added to address this issue.
The phase-offset information extracted by processor 32 is applied to filter 36 via summer 17 . The phase-offset information, being updated once per frame, provides a sampled data representation of the frequency components of the client and OPVC1 clock differences, which when summed with the recovered phase difference produced by subtractor 38 , nulls out the low frequency error, essentially eliminating the impairment.
Node-to-node pointer processing impairments are introduced by intermediate nodes; i.e., nodes between the ingress node of a signal, and the egress node of a signal. More particularly, the ingress node participates in pointer generation, the egress node participates in pointer interpretation, and the intermediate node participate in pointer interpretation and generation—which we call pointer processing. As a signal arrives at an intermediate node (with respect to the client ingress node, node A), for example, node B, the clock of the arriving signal is extracted, and the OPVC1 frame is extracted from the payload of the OPTU1 frame in a manner similar to that described above in connection with SONET frames (i.e., with the aid of the pointer within the OPTU1 frame's header). At this point the extracted OPVC1 frame is operating on timing that was derived from node A, however, to transmit the OPVC1 frame to the next downstream node it must be operating on local, node B, timing. This is accomplished by adjusting the pointer value (pointer processing) inserted into the outgoing OPTU1 frame in a manner that is also similar to that described in connection with SONET frames. The pointer processing shifts the entire OPVC1 frame within the associated OPTU1 frame, and when the clocks of nodes A and B are relatively close to each other, the negative and positive justifications create low frequency timing components associated with the OPVC1 frame that are embedded in the OPTU1 frame. These low frequency components propagate through the network and ultimately appear at the egress client de-mapper (the operation of this is described above). As was discussed, arbitrary low frequency components cannot be eliminated by the de-mapper low pass filter, and the resulting wander, which can accumulate as the signal passes through network nodes constitutes a problem for communicating client signals that are SONET signals.
Borrowing from a proposal by Michael Klein et al for advanced pointer processing in SDH/SONET networks, in an article entitled “Network Synchronization—A Challenge for SDH/SONET?”, IEEE Communication Magazine, September 1993, pp 42-50, al advanced pointer processor would operate as described below.
The general concept behind the advanced pointer processor is to generate pointers such that they contain predominantly high frequency energy which is filtered out at succeeding nodes before generating new pointer values. Specifically, an OPTU1 frame and its timing are recovered from the incoming data stream. Through interpretation of incoming pointer information, an OPVC1 clock is generated from the incoming OPVC1 data stream contained within the OPTU1 frame and any incoming pointers generated by upstream nodes are filtered out (the pointers are responsible for node-to-node timing impairments). The extracted data can then be injected into an OPTU1 frame outgoing from the node under control of an adaptive pointer generator and then be transmitted out of the node. The adaptive nature of the pointer generator provides spectral shaping of the impairments caused by pointer generation, that is, the frequency content of the noise created by the generated pointers is shifted to higher frequencies. This spectral shaping, which is derived from concepts based on sigma-delta modulation, creates a noise spectrum that allows downstream pointer filters (discussed above) to easily remove the pointer generated timing impairments. The combination of incoming pointer filtering and adaptive outgoing pointer generation makes up an advanced pointer processor.
In accord with the principles disclosed herein, each node undertakes pointer processing that aims to minimize the low frequency components by performing spectral shaping of pointer impairments. It does so by adaptively undertaking negative justifications and compensating positive justifications (or vice versa) where, otherwise, no justification is necessary. In other words, each node injects voluntary positive and compensating negative justifications. This is effected with a circuit like the one shown in FIG. 4 . It is similar to the FIG. 3 circuit, except that VCO 37 is replaced by ATM circuit 42 , and includes an additional feedback loop, through compensation filter 40 having a transfer function X(z) and summing node 41 . The output of buffer 34 in FIG. 4 delivers OPVC1 frames that are processed via processor 43 , which adds outgoing pointer information and generates outgoing OPTU1 frames.
In this implementation the compensation filter 40 is required because the incoming pointer filter 36 is located such that it not only filters the incoming write clock (processor 32 produces the write clock which drives write counter 33 which in turn is processed by subtractor 38 , thereby producing a write clock component which would then be filtered by filter 36 ), but also filters the outgoing pointers (processor 39 produces the pointer adjustment signal that controls the read counter 35 which in turn drives the subtractor 38 , thereby producing a read clock component that contains pointer adjustment phase information which would then be filtered by filter 36 ). Since the outgoing pointers must not be filtered (that would essentially nullify the pointer operation which is required in order to compensate for the input and output clock differences), a compensation circuit, compensation filter 40 , must be provided to nullify the effects of incoming pointer filter 36 on any adaptive outgoing pointer generation functions performed by adaptive threshold modulator 42 .
To determine the transfer function of filter 36 , it is noted that the address of read counter 35 , which can be represented by a cumulative phase signal, φ r (z), is effectively equal to the sum of the phase of the node's clock (gated to account for the overhead bytes), φ n (z), and any phase shift due to pointer adjustments, φ p (z); i.e., φ r (z)=φ n (z)+φ p (z). The pointer adjustment signal is the cumulative phase shift resulting from pointer justification operations, either no pointer justification, positive justification of four bytes, or negative justification of four bytes. It is also noted that the address of write counter 33 can be represented by a cumulative phase signal, φ w (z).
The output signal produced by the phase detector 38 that is applied to summing node 41 , which is a number that changes each time the read or the write counters ( 35 and 33 , respectively) are incremented, and also represents a phase signal, is the difference between the read and write addresses D o (z)=φ n (z)+φ p (z)−φ w (z). The output of filter 40 is X(z)φ p (z), and therefore the input to filter 36 is D o (z)+X(z) φ p (z), or φ n (z)−φ w (z)+φ p (z)(1+X(z)). The output of filter 36 , therefore, is
[φ n (z)−φ w (z)+φ w (z)(1+X(z))]F(z). (1)
We observe that for proper operation, the input to adaptive threshold modulator 42 must equal the phase difference between the read clock (which includes pointer adjustments) and the filtered write clock, that is, the outgoing pointer adjustments that appear as part of the read clock must not be filtered. Therefore, for proper operation the input to adaptive threshold modulator 42 must correspond to
(φ n (z)−φ w (z))F(z)+φ p (z). (2)
Setting equation (1) equal to equation (2) yields
X ( z )=(1 −F ( z ))/ F ( z ). (3)
We found that the transfer functions pair
X ( z ) = ( 1 - z - 1 ) ( 1 - az - 1 ) K ( 1 - bz - 1 )
and ( 4 ) F ( z ) = ( K K + 1 ) ( 1 - bz - 1 ) 1 - ( 1 + a + Kb K + 1 ) z - 1 + ( a K + 1 ) z - 2 ( 5 )
with X(z) representing a differentiated first order high pass function and F(z) representing a second order low pass filter function, work well.
The implementation suggested by equation (4) for X(z) includes a (1−z −1 ) term, which represents a differentiator function, followed by a high pass filter. The input to the X(z) function is the cumulative phase output of the adaptive threshold modulator 42 , which is represented by a stairstep function that jumps up or down by four bytes of phase magnitude whenever a positive or negative pointer justification occurs. Differentiation of this type of signal produces a series of unit impulses at each positive or negative pointer justification. By including this differentiation function as part of the ATM functionality and having processor 39 operate on simple positive or negative justification indications instead of cumulative phase, the differentiation term in X(z) can be eliminated.
The resulting implementation of FIG. 5 shows the physical implementation of these filters, including the implementation of the ATM circuit 42 . It should be noted that the quantizer block simply makes the pointer adjustment decisions instead of outputting cumulative phase information.
This processing performed at node B is performed at each succeeding downstream node until the client signal egress node is reached. As a signal arrives at the egress node, for example, node Z, the clock of the arriving signal is extracted, and the OPVC1 frame is extracted from the payload portion of the OPTU1 frame in the same manner as described for node B. Also, as for node B, an OPVC1 clock is generated from the incoming OPVC1 data stream and any incoming pointers generated by upstream nodes are filtered. The signal is then processed as described above for the egress node de-mapping function.
Although the present invention has been illustrated and described herein with reference to preferred embodiments and specific examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and/or achieve like results. All such equivalent embodiments and examples are within the spirit and scope of the present invention and are intended to be covered by the following claims. | An arrangement that allows transmission of client signals with higher clock fidelity is achieved by developing a phase offset measure at an ingress node, communicating it to the egress node, and recovering the client's clock from the received data and from the received phase-offset information. The ability to recover the client's clock with high fidelity is enhanced by adaptive pointer processing in intermediate nodes and the egress node of the network that the client's signal traverses. The adaptive pointer processing filters incoming pointers from upstream nodes and injects new positive and negative pointer justifications in excess of what is minimally necessary to allow them to be filtered by successive nodes and insure proper transmission over a network that employs a protocol involving framing layer frames embedded in communication layer frames. Illustratively, the network protocol is an extended ITU Recommendation G.709 Digital Wrapper protocol, arranged to employ frames of 15240 columns by four rows. | 7 |
FIELD OF THE INVENTION
This invention relates to block-type drywall construction and, more particularly to a brick drywall construction method and the means for carrying it out and is related to the invention described and claimed in Applicants' Canadian patent applications 2,158,771 filed Sep. 21, 1995 and 2,192,123 filed Dec. 5, 1996, the latter constituting a part of the present application.
Although the method and means are applicable to building blocks in general, i.e. bricks and concrete blocks, the construction is preferably of brick. The constructed wall is designed to be, essentially, self supporting and simulate the appearance of a brick wall of normal mortared construction.
DISCUSSION OF THE PRIOR ART
Drywall construction is used generally for low walls and takes the form of a wall constructed of unitary building units or blocks which can be stacked to provide a self supporting wall structure, a securing cement, or mortar, being dispensed with.
U.S. Pat. No. 5,048,250--Ellias, issued Sep. 17, 1991, is directed to a building block per se which is designed for stacking in a drywall structure. The blocks are provided with vertically oriented holes, which in stacking are vertically aligned through row layers, through which rods may be passed to provide reinforcement of the structure.
U.S. Pat. No. 4,426,815--Brown, issued Jan. 26, 1984, is directed to a mortarless concrete building block provided with key means locking one layer of blocks to the underlying or overlying next layer. Here again reinforcing rods may be used for added strength.
U.S. Pat. No. 2,199,112--O'Leary, issued Apr. 30, 1940, is directed to an insulated building block having, in one instance, a simulated brick construction surface being applied to the face of the block.
U.S. Pat. No. 2,006,462--Kupper, issued Jul. 2, 1935, is directed to a miniature building system wherein individual building blocks are mounted on and secured by vertical rods passing consecutively through layers of the blocks.
GENERAL DESCRIPTION OF THE INVENTION
The present invention is directed to a drywall construction method and means facilitating ease of construction while, at the same time, providing a strong structure with the appearance of a mortared block wall. The preferred construction block is a standard size brick modified somewhat to accommodate the features of the present invention.
According to the invention described in Canadian patent application 2,158,771, supra, the layers of brick, in regular construction format, are interleaved with relatively thin layers of belt-like material which provides the appearance of a mortar strip between the layers. The standard construction brick, upon which the present description is primarily based, is provided with holes, usually three, passing vertically through the brick with the holes symmetrically situated so that the holes of offset brick layers will align between layers with, in the case of the three hole brick, the centre hole coinciding vertically with the butting ends of the bricks in the layers immediately above and below that particular centre hole. A mating hole structure is provided in the belt-like material. Simulated vertical mortar pads are inserted between abutting brick ends.
A particular feature of the invention of the aforementioned application is the use of short pin members, for instance tubes, which are dimensioned to fit snugly into the holes in the brick and the belt. The length of the pin member is preferably substantially equal to the vertical height of a brick and is inserted into the hole of a brick to the approximate extent of half its length, the other half of the pin member acting as a locating pin upon which the subsequent layer of simulated mortar and bricks are laid. The pin members act as means for securing the brick and belt layers against horizontal displacement with respect to each other. In addition, the pins, in view of their snug fits in the brick holes, provide an additional degree of vertical stability. When the pins are tubular in form, vertical reinforcing rods may be readily inserted through a number of laid layers of bricks and insulating belts.
This type of construction reduces labour costs in the building of walls etc., is economical and, in view of the fact there are no rigid joints the wall may be subjected to considerable vibrational stress without consequent cracking and deterioration thus rendering the construction useful for earthquake prone areas.
The present invention is concerned with the inserts between the ends, or the abutting surfaces, of the bricks in a horizontal layer which are utilized to align and maintain the alignment of brick ends in the horizontal layers. In addition, the inserts may act as a means of securing the brick rows against lateral movement between the bricks and the belt layers between the bricks.
To this end the inserts are provided with vertical flanges which extend horizontally into slots provided in the abutting surfaces, usually ends, of the bricks of a row. In this case the inserts are of firm material and act as joining and alignment strips between brick ends when inserted into facing slots on the brick ends, the slots providing a close fit for the inserts. In one form of the invention, there are two inserts, one near each outside edge of the abutting brick ends, which inserts are of such a length, in the horizontal direction of the brick row, to maintain separation of the bricks and provide a portion which appears as being the vertical mortar strip between abutting brick surfaces. In another form of the invention only one insert is used between abutting brick surfaces.
In order to provide security between the bricks and the horizontal belts, grooves can be provided in the belt to accept the top and bottom edges of the inserts to assist in maintaining alignment between the belts and the brick rows. The belts can be provided with thickened outer edge parts which are provided with bottom and top surfaces grooved to accommodate the upper and lower longitudinal edges of the inserts. In an alternate form the inserts can be provided with extended flanges which, for instance protrude upward and downward, respectively, to hook over the thickened outer parts of the belt, preferably the inside edges of the thicker parts. It is contemplated that pins, as mentioned above, may be used to provide further security.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an exploded view of a brick drywall construction according to the invention described and claimed in Canadian patent application 2,158,771.
FIG. 2 shows an exploded view of a brick drywall construction utilizing the features of the present invention.
FIGS. 3 shows an exploded and enlarged view, of a portion of FIG. 2, showing more clearly one form of the insert according to the present invention.
FIG. 4 shows an exploded and enlarged view, of a portion of construction showing more clearly a modified form of insert.
FIGS. 5, 6, and 7 show, in greater detail, alternate forms of inserts which may be used according to the invention.
FIG. 8 shows a form of an integrated insert unit.
FIG. 9 shows a form of a drywall construction related to the construction shown in FIG. 4.
FIGS. 10 and 11 show plan and end views, respectively, of the insert used in the construction according to FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, which shows an exploded view of the brick or block wall as described in Canadian patent application, 2,158,771, two horizontal rows of bricks 1, are laid end to end in standard brick wall construction, in horizontally offset position whereat the abutment of two bricks in the upper layer overlies the centre of a brick in the layer immediately below. The bricks, in this instance, are provided with a longitudinal series of three equally spaced and longitudinally separated holes 4 which pass vertically through the brick, the centre hole of the series being located centrally of the brick and the longitudinal spacing of the holes is such that, if the series of holes was continued, the subsequent hole centre-lines would substantially coincide with the central position between abutting end surfaces of the bricks in a layer.
The bricks of each row are horizontally separated by an insert 2 having the dimensions of a mortar separation layer. The inserts simulate the appearance of mortar and may be colored as desired. The insert is, preferably, provided with centrally located, rectangular, upper and lower extensions 3 which are designed so that the horizontal dimensions thereof substantially equal the diameter of the vertical holes 4 in the bricks 1.
A belt 5, having a simulated mortar appearance and colored as desired, is provided with a longitudinal series of holes 6 which are longitudinally spaced in accordance with the spacing of the holes in the brick 1 and have diameters equal to that of the holes in the brick. The belt 5 is laid between the layers or rows of bricks 1 with the holes 6 of the belt overlying the holes 4 of the bricks. The longitudinal spacing of the holes in the brick are such that, when the bricks are laid in standard horizontal-row construction format, the centre hole of a brick will coincide, longitudinally of the row, with the centre of the abutment spaces of the rows of bricks immediately above and below that centre hole. As a consequence, the belt 5, when positioned on a brick row will have holes therein which coincide with the abutment spaces of that row. The purpose of the extensions 3 on the inserts 2 will now become apparent since the belts 5 and the bricks 1, above and below an insert 2, will provide holes 6 and 4 which will accept the extension 3 of the insert 2. The insert 2 is, accordingly, secured between the belt layers 5 by the extensions 3. Although the extensions 3 could be dispensed with, it is preferred that they are present to secure the inserts 2 in position.
In order to secure the belts in position between brick layers and provide stability to the construction, pins 7 are provided. The pins 7, preferably, have a diameter substantially equal to that of the holes 4 and a length approximating the thickness of a one layer of bricks 1 and one layer of belts 5. The pins 7, preferably, have, at least, a somewhat resilient surface, or are split longitudinally, whereby slight imperfections in the brick holes 4 will not prevent a pin 7 from entering thereinto. In constructing a wall, the pins 7, are tapped through a belt layer into the brick layer below leaving approximately one half the pin length projecting above the belt. In this manner the belts and brick layers are secured, by the pins, against horizontal movement with respect to each other.
The above mentioned Canadian patent application should be referred to for further information on this particular construction.
Referring now to FIGS. 2 to 11 inclusive, which depict features of the present invention, FIG. 2 shows a construction similar to FIG. 1 with the exception that the vertical inserts 2 have been substituted for by flat rectangular plates 8 which are notched into rectangular recesses or slots 9 provided in the abutting end surfaces of the bricks of a horizontal layer. The vertical outer sides of the inserts 8 are positioned to coincide with the normal mortar fill between the brick ends to simulate normal mortared brick construction appearance.
FIG. 3 shows a form of the invention in greater detail. Inserts 8 are notched into the brick-end slots 9 and it will be apparent that when so notched into facing brick-ends the brick-ends will be held in alignment providing the inserts 8 are of relatively rigid material, which is preferably the case. In order to economize in the material required for the belts 5, the belt may take the form of a thin central web 11 having thickened, rectangular in cross-section, outside edge parts 12 which, preferably, protrude above and below the web 11, upon which the brick 1 rests when laid on a belt 5. The inserts 8 are provided with inside, upper and lower edge, extensions 8a, 8a, which overlap the inside edges of parts 12 of belt 5. The extensions provide lateral movement security between belts 5 and brick 1 when both ends of the bricks are so secured. A clearer view of the insert configuration is provided in FIG. 5. Pins 7 can be used for additional security to prevent relative movement between the belts 5 and brick 1 rows.
In a further embodiment, as shown in FIG. 4, the inserts are integrated into a tubular unit 10 in a cross configuration in cross-section. In this configuration an opposed pair of the arm parts 10a are close fitted into slots 13 provided, singly, in the facing brick-end surfaces, whereas the other pair of arms 10b of the cross form the simulated, vertical mortar strips of a brick wall construction. A particular advantage of this unitary construction is that it is tubular in form and can be economically extruded.
It is feasible to provide the opposed arm pairs 10a, 10b in equal widths but, it is believed that the wider arms, with sides spaced to permit the entry of a pin 7 therebetween, has a particular advantage if it is desired to use pins 7 at the cross locations as shown.
It is preferable to over and undercut the narrow cross ends 10b so that the wider arms will sit between the protruding portions 12 of the belt 5 to laterally secure the belt, the facing bricks and the cross construction with respect to each other.
Referring now to FIG. 6, a modified form of an insert 14 is shown in the form of a thin, rectangular-in-cross-section, plate 14 which is close fitted into accommodating slots 9 provided in abutting brick 1 surfaces. This is a very economical form of insert. However, in order to provide security, in this instance, the parts 12, of belt 5, should be provided with grooved upper and lower surfaces 12a, 12b, into which slightly extended upper and lower ends of the inserts seat to provide lateral security.
FIG. 7 shows a modified form of the inserts of FIG. 6 wherein the inserts are in the form of plate parts 14 with rectangular protrusions 14a which are designed to sit between the brick ends to simulate the mortar appearance while the plate parts 14, protruding into the brick slots 9 and lying between belt edge parts 12, provide the alignment and security. This construction allows the slot 9 to be placed further from the outside surface of the brick and provides a more robust construction.
FIG. 8 shows a further modification of the insert, according to the present invention, wherein two insert parts 14, corresponding to similarly numbered parts in FIG. 5, 6 or 7 are integrated into a unitary construction by an inter-connecting web 15. The particular advantage of this construction is the extra security provided by the unitary construction and the ease of use since two inserts are inserted simultaneously. The web 15 may be provided with extensions 15a which can be inserted into the underlying and overlying brick and belt holes in a constructed wall thus securing the inserts with respect to the bricks and the belt which is provided with holes coinciding with the holes in the bricks. The extensions 15a may be removed from the joining web 14 along the dashed line. Furthermore, if it is desired to save weight and material the central area of the web, shown in dashed outline, need not be present.
Referring now to FIG. 9, a modified form of construction, related to that of FIG. 4, is shown. In this construction the insert 10 has been substituted for by a modified insert 16 which is, preferably, rectangular in cross-section and tubular. In addition, for increased security of construction and economic reasons, the pins 7, of FIG. 4, are substituted for by extensions (pins) 16a of the insert 16 to form an integrated insert-pin combination 16, 16a. In order to accommodate the pin parts 16a, the holes 4, provided in the bricks may be rectangular in cross section and dimensioned to provide a snug fit.
As best shown in FIGS. 10 and 11, the insert 16 is provided with vertically oriented, rectangular and lateral wing-like, flanges 17 midway of the ends of the insert 16, The flanges 17 are designed to extend between abutting surfaces of brick ends, as shown in FIG. 8, and vertically-narrow end plates 18 are provided, at right angles to the flanges 17, to simulate the vertical mortar between brick ends. The flanges 17 are, preferably, notched at the outer corners 19 so that the flanges 17 will fit between the protrusions 12 of the belt 5a, FIG. 8. The bricks 1 and the belts 5a are provided with rectangular holes 6a to accommodate the rectangular extensions 16a. In the construction shown in FIG. 8, the bricks may be held in position by using only the inserts 16 between abutting brick ends and the pin parts 16a will protrude through belts 5a into the center holes of bricks in the layers immediately below and above the layer in which the inserts are inserted into brick end surfaces. For further security, pins 16b, not provided with lateral extensions 17, may be utilized at brick-hole locations other than where the integrated inserts are employed.
Although preferred embodiments of the invention have been described further variations and modifications may be made without departing from the spirit and scope of the invention which is defined in the claims appended hereto. | A drywall construction simulates a mortared block or brick wall construction by the use of simulated horizontal mortar layer inserts between the layers of building blocks and vertical inserts between abutting end surfaces of blocks in each layer, the horizontal layer insert being in the form of a belt, the belt layer being substantially non-compressible and the vertical inserts being provided with parts which extend across the space between abutting block surfaces of a wall construction and into slots provided in the abutting surfaces to secure interconnection and alignment of block ends and simulate vertical mortar inserts between vertical and abutting surfaces, the inserts may be provided with flanges or protrusions which cooperate with holes or grooves in underlying or overlying belt layers to secure the inserts, and the block surfaces, cooperating therewith, against lateral movement with respect to the layers, the belts or both. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to object-orientated processor platforms, and in particular to an apparatus and method of implementing object-orientated systems using heterogeneous execution units with access to shared memory.
BACKGROUND OF THE INVENTION
[0002] The design of electronic systems, particularly in the communications field, is becoming more and more complex. The standards are fast moving and the functionality required of a system is no longer just implemented as hardware, but rather as an interaction of multiple software and hardware components. The blending of the software and hardware design flows is starting to drive many of the software programming techniques, in particular object orientated design, into the hardware implementation process.
[0003] The basic conceptual component of any object orientated system is an object. This has the form shown in FIG. 1 which depicts a commonly used object-orientated system consisting of some object data 2 , and a number of methods 3 which operate upon that data to update it, transform it or extract it. The methods applicable to an object define its class, with all objects that share an identical set of methods belonging to the same class. A class definition includes two special types of method which act as object constructors and object destructors. Object constructors are methods which can create new objects of a particular class, either when invoked by another object method or when triggered by some external stimulus such as the arrival of data on an input port. Object destructors perform the opposite function, destroying a specified object when invoked.
[0004] In order for multiple objects to interact as a system, an object runtime environment 6 is required. This provides a mechanism 7 , 13 for invoking object methods via the passing of messages between objects. An object method 3 is invoked whenever a suitable ‘call’ message is sent to that particular method. The invoked method may then generate a ‘return’ message which informs the invoker of that method, of the result of the method invocation. Also present in the runtime environment is a synchronisation facility 8 which can be used to ensure that two conflicting methods are not invoked on the same object simultaneously. A final essential part of the runtime environment is a mechanism 9 which supports the creation and deletion of objects by allocating and deallocating the resources required by the object.
[0005] The way in which the features of an object orientated system are mapped onto a typical software implementation is also shown in FIG. 1. For each distinct method which may be applied to an object, a sequence of instructions 16 are stored in the processor's memory 10 . For each object which is a part of the system at any given time, an area of the processor's memory 14 is allocated for the storing of the object data. The object runtime environment 6 is provided as a sequence of instructions which implement the operating system and additional language specific runtime features. In the simplest case, message passing 7 and synchronisation 8 are combined using a single threaded call and return mechanism. This ensures that only one method is being executed by the processor at any given time. The creation and deletion of objects is handled by a set of memory management routines 15 which control the allocation of memory, assigning data areas to objects as they are created and recovering the data areas of objects as they are destroyed.
[0006] It is possible to implement object orientated software systems on multiple processors using symmetric multiprocessing (SMP), where multiple identical processors 11 access the same shared memory via a shared bus, crosspoint switch or other similar mechanism. This preserves the model shown in FIG. 1 for a single processor system with the additional requirement that explicit synchronisation capabilities be provided between the processors. In this case, synchronisation becomes an additional operating system task compromising efficiency.
[0007] Symmetric multiprocessing scales poorly when more processors are added to the system because in addition to accessing object data in the shared memory, the processors must also fetch executable code from the same shared memory for operating system routines and method invocations. A more significant problem occurs in systems where a subset of the methods to be invoked cannot be efficiently implemented in software. In this case, the conventional way to introduce hardware acceleration without breaking either the object orientated system design or the symmetric multiprocessing model is to effectively extend the instruction sets of the processors being used—an approach which is not always practical.
[0008] An alternative approach to implementing object orientated software systems on multiple processors uses distributed processing as illustrated in FIG. 2. An example of a processor designed specifically for distributed processing applications would be the Inmos™ Transputer™.
[0009] In an object orientated distributed processing system there are multiple processors 20 a , 20 b , 20 c , each with its own local memory area 21 a , 21 b , 21 c for storing object data 22 a , 22 b , 22 c and executable code for method definitions 23 a , 23 b , 23 c with runtime support 24 a , 24 b , 24 c . These processors are connected together using a relatively low bandwidth message bus or switch 25 , since all the fast processor to memory accesses are performed locally. Method ‘call’ messages are passed between the processors via the messaging system in order to invoke the execution of the methods stored in local memory. These methods act on locally stored object data before optionally sending a ‘return’ message to the invoker.
[0010] The runtime support for message passing and synchronisation are implicit in the message passing infrastructure of the distributed system, with the runtime support present for each processor providing localised management of resources for object creation and deletion.
[0011] Distributed multiprocessing can scale well for any systems where object data can be statically assigned to one particular processor. However, the implication of this is that the types of methods which may be applied to that object are restricted by the capabilities of that processing unit which hosts the object. It is impractical to implement some methods on a flexible processor and others on a separate hardware accelerator, since the object data would need to be copied around the system in a non-object orientated manner.
[0012] If hardware acceleration for specific methods is required, the conventional way to achieve this without breaking either the object orientated system design or the distributed processing model is to effectively extend the instruction sets of the processors being used.
[0013] In multiprocessor systems one of the major areas of potential difficulty is writing code in such a way as to make use of the available processing resources. With heterogeneous systems this problem has been particularly acute, and often separate code has been written for individual processing units. This makes understanding, maintaining and, most importantly, scaling the code base as processors are added, significantly more difficult.
[0014] With SMP systems this problem is significantly reduced as a single set of source files is used, but SMP architectures do not typically scale well in terms of performance above four processing units.
[0015] It is a general objective of the present invention to overcome or significantly mitigate one or more of the aforementioned problems.
SUMMARY OF THE INVENTION
[0016] According to a first aspect of the invention there is provided an object orientated heterogeneous multiprocessor architecture comprising: a plurality of execution units amongst which object methods are distributed; a runtime support; a shared memory for storing object data and which is accessible by the execution units and by the runtime support; and an invocation network for carrying method invocation messages between execution units and between the runtime support, and any combination thereof, whereby object based source code is distributable across a variable number of execution units, and the invocation network is logically distinct from any mechanism for accessing the object data stored in the shared memory.
[0017] In a preferred embodiment the architecture is implemented on a single integrated circuit or chip.
[0018] An advantage of this architecture over conventional SMP systems is that a larger number of execution units can be supported. Thus, for a given number of parallel executing threads, fewer threads need to be assigned to each of the execution units. The result is that the overall overhead associated with context switching between threads is reduced and as the number of threads increases, the performance improvement over SMP systems becomes more pronounced.
[0019] Another advantage of the disclosed architecture is the efficient use of message passing resources as raw object data is not passed over the invocation network, as is the case with the conventional distributed multiprocessing approach.
[0020] The disclosed architecture is advantageous as the unified nature of the runtime support enables the heterogeneous execution units to communicate together in a single system using the standardised method invocation and shared memory interfaces.
[0021] According to a second aspect of the invention there is provided a method of operating an object orientated heterogeneous multiprocessor architecture comprising the steps of: concurrently activating a plurality of threads under the control of an application program or as a response to external events; and executing each of the plurality of threads by sequentially invoking a number of different object methods on a plurality of different execution units via an invocation network.
[0022] In a preferred embodiment, the step of sequentially invoking a plurality of object methods comprises: accepting object method invocations from the invocation network; and executing the object methods specified by the object method invocations as prescribed by the programming and configuration of the execution units.
[0023] In a further embodiment, the step of executing the object methods comprises: modifying, transforming or extracting object data held in the shared memory area.
[0024] According to a third aspect of the invention there is provided a method of managing communication in an object orientated program execution environment comprising the steps of: generating method invocations using execution units; passing the method invocations over an invocation network; and nesting method invocations between multiple execution units via a method invocation interface.
[0025] According to a fourth aspect of the invention there is provided a method of invoking an object method comprising the steps of: passing a control message requesting the invocation of an object method on an object from a first execution unit to a second execution unit using an invocation network; and executing the control message to invoke the object method on the object using the second execution unit.
[0026] According to a fifth aspect of the present invention there is provided an invocation network capable of being used with the architecture of the first aspect of the invention described above, comprising: a messaging bus or switch for conveying control messages issued by execution units; and a plurality of method invocation interfaces for connecting the messaging bus to the execution units.
[0027] According to a sixth aspect of the present invention there is provided a runtime support capable of being used with the architecture of the first aspect of the invention described above, and having at least one object comprising: at least one memory allocation unit, wherein the runtime support is provided as a collection of resources in communication with other hardware and software objects via an invocation network. Preferably, the or each object further comprises one or more of: at least one counter, at least one event timer, and at least one semaphore.
[0028] According to a seventh aspect of the present invention there is provided an input/output I/O execution unit which can intelligently manage incoming and outgoing data, comprising: at least one input/output controller for formatting data into a predetermined object data structure, and for sending a method invocation over an invocation network for indicating the availability of the object data to other execution units.
[0029] According to a eighth aspect of the present invention there is provided a computer system comprising an object orientated heterogeneous multiprocessor architecture of the first aspect of the invention as described above.
[0030] In a preferred embodiment the computer system comprises at least one of the devices of the fifth to seventh aspects of the invention described above.
[0031] Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Embodiments of the invention will now be described by way of example only, with reference to the drawings in which:
[0033] [0033]FIG. 1 is a schematic block diagram of a known object orientated system using symmetric multiprocessing;
[0034] [0034]FIG. 2 is a schematic block diagram of a known distributed object orientated system with multiple processors;
[0035] [0035]FIG. 3 is a schematic block diagram of an embodiment of an object orientated heterogeneous multiprocessor architecture of the present invention;
[0036] [0036]FIG. 4 is a block diagram showing the flow of messages passed between execution units during operation of an embodiment in accordance with the present invention;
[0037] [0037]FIG. 5 is a block diagram showing the flow of messages passed between two separate execution units that invoke one or more methods on different objects via a third common execution unit for an embodiment in accordance with the present invention;
[0038] [0038]FIG. 6 is a block diagram showing the flow of messages passed between execution units for synchronous and asynchronous method invocations in accordance with an embodiment of the present invention;
[0039] [0039]FIG. 7 is a block diagram showing the flow of messages between execution units for load balancing operation for an embodiment in accordance with the present invention;
[0040] [0040]FIG. 8 is a schematic block diagram showing a messaging interface connecting the invocation network to the execution units for an embodiment in accordance with the present invention;
[0041] [0041]FIG. 9 is a schematic block diagram showing the transfer of data to and from shared memory for a method forming part of a non-conglomerate object for an embodiment in accordance with the present invention;
[0042] [0042]FIG. 10 is a flow diagram showing the interaction of an object input data method with other object methods within an object orientated system in accordance with the present invention; and
[0043] [0043]FIG. 11 is a flow diagram showing the interaction of an output data method with other object methods during its execution in an embodiment in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] The invention is based around an object orientated structure. Each object is responsible for its own behaviour, and can be implemented on any of the available processing resources. Consequently the resulting solution is based around a single set of source files describing the classes, which is easier to understand, use, support, maintain and re-use. The architecture is inherently scalable, with increased performance being achieved by simply adding more object resources. A significant advantage afforded by this architecture is that the software source remains unchanged when the architecture is scaled, when new objects are added, or when objects are regenerated with a different constitution, for example if software based objects are changed to hardware based objects.
[0045] [0045]FIG. 3 shows an example of the way in which the objects are mapped onto the hardware components of a preferred embodiment, with object data 31 a , 31 b , 31 c , 31 d , 31 e , 31 f residing in shared memory 32 and object methods 43 a , 43 b , 43 c , 44 a , 44 b , 45 a , 45 b distributed across a number of execution units 33 , 34 , 35 , which may be conventional processors 35 , custom microcoded engines 34 or direct hardware method implementations 33 .
[0046] Objects where all elements of the object (data and methods) are bound together in one location i.e. not using shared memory are referred to as conglomerate objects, as shown in FIG. 2. Objects which are distributed across the system (i.e. using shared memory) are referred to as non-conglomerate objects, as shown in FIG. 3. A system of the form shown in FIG. 3 does not preclude the use of conglomerate objects.
[0047] A runtime support 37 as shown on the left hand side of FIG. 3, consists of a set of service objects that may take either conglomerate or non-conglomerate forms (i.e. conglomerate service objects or non-conglomerate service objects). The examples shown in FIG. 3 are conglomerate service objects, since all the methods and data are shown blocked together to give a memory allocation object 38 , semaphores object 39 , timers object 40 and counters object 41 . In practice, these objects are also implementable as non-conglomerate service objects within the scope of the invention. Service objects may be implemented using any combination of execution units (hardware, microcoded engine or processor based).
[0048] As object methods 43 a , 43 b , 43 c , 44 a , 44 b , 45 a , 45 b (non-conglomerate objects) are distributed between embedded processors 34 , 35 and dedicated hardware 33 , an invocation network 42 is provided to communicate between them. In object orientated systems there is very extensive communication between different objects (which may all be operating in parallel). To this end, any suitable messaging system such as collision detect multiple access busses, token busses, token rings, packet and cell switch matrices or wormhole routing switch matrices may be used to form the invocation network 42 .
[0049] In contrast to existing message busses or switches, the message invocation network 42 shown in FIG. 3 is designed specifically for carrying method invocation messages between method implementations of both conglomerate and non-conglomerate objects distributed over multiple parallel execution units 33 , 34 , 35 , 37 .
[0050] Since the methods associated with a particular object may be distributed across a number of hardware or software blocks, the data needs to be stored such that it is quickly accessible to all the execution units. A number of mechanisms for implementing the shared memory subsystem will satisfy this criteria, including multiport memory controllers, multiport caches, distributed caches with cache coherency support or any combination of these techniques. The memory may be made accessible to the execution units 33 , 34 , 35 , 37 via conventional busses, crosspoint switches, address interleaved multiple busses or any combination thereof.
[0051] In order to provide runtime support for the objects in the system, a number of additional services are required which are accessible to all objects in the system via the message invocation network 42 and which may be implemented either as dedicated hardware or as software tasks. Examples of such services include additional shared access runtime objects for memory management 38 , synchronisation semaphores 39 , timers 40 , counters 41 , error handling, exception handling and any combination thereof.
[0052] Invocation Network
[0053] The threads of execution in the system are passed between execution units as methods are invoked. The method invocation and any subsequent return both generate traffic on the invocation network 42 .
[0054] Examples of the way in which messages are passed between execution units 33 , 34 , 35 , 37 are shown in FIGS. 4, 5 and 6 , where the passed messages are indicated as black arrowed lines. The figures show active execution of individual execution units plotted against an arbitrary time axis.
[0055] The first example in FIG. 4 shows that method calls via the messaging interface 42 may be nested between execution units of different types. In this case, a method call is made from the thread of execution currently active on a processor component which corresponds to the execution of object 1 method 1 51 . The method call invokes execution of object 2 method 2 52 on the microcoded engine, which in turn invokes the execution of object 3 method 3 53 on the hardcoded state machine. Note that there is no limitation on which types of execution unit may invoke methods on other execution units. It is perfectly viable for a state machine or microcoded engine to invoke a software method, or for any other combination of invoker and target method implementation to be used.
[0056] On completion, the state machine component returns a message to the microcoded engine. Similarly, the microcoded engine will also send a return message once object 2 method 2 52 has completed. The operating system on the microprocessor may support multitasking, in which case an alternate thread of execution 54 will have been scheduled after the initial method invocation. The return message will only be consumed once the alternate thread of execution has been suspended and the thread associated with object 1 method 1 51 restarted.
[0057] [0057]FIG. 5 shows the way in which two separate execution units may invoke one or more methods on different objects via a third common execution unit. In this case, execution unit B is initially running object 2 method 2 52 , which passes a message to execution unit C in order to invoke object 3 method 3 53 . Shortly afterwards, execution unit A attempts passing a message to execution unit C in order to invoke object 4 method 4 55 . Since execution unit C is busy, this request is blocked until the execution of object 3 method 3 53 has completed.
[0058] [0058]FIG. 6 illustrates the use of synchronous and asynchronous method invocations. The conventional mode of operation is for method invocations to complete with a return message, where execution of the calling method is suspended until the invoked method completes. This is illustrated by the way in which object 1 method 1 51 passes an invocation message 57 to object 2 method 2 52 and then execution unit A suspends until the return message 56 is received. The asynchronous mode of operation is illustrated by the invocation of object 3 method 3 53 on execution unit C. Here, execution on the invoking execution unit continues as soon as the message has been sent and no return message is passed back to the calling method.
[0059] The act of method invocation does not preclude the continued execution of the method on the invoking execution unit, nor does the sending of a return message preclude the continued execution of an invoked method on its execution unit.
[0060] Load Balancing
[0061] In some instances performance can be dramatically improved if multiple execution units are capable of executing the same method or set of methods on different objects of the same class. An example of load balancing operation is shown in FIG. 7. The invocation network 42 supports a mechanism whereby the messaging interface 46 , 47 , 48 of the invoking execution unit 33 , 34 , 35 can be provided with a range of execution unit targets which implement a given method.
[0062] In the event that the first choice target execution unit is busy, as is the case for execution unit C in the example shown in FIG. 7, any attempt to invoke the required method on that execution unit will be blocked. The invoking execution unit may then attempt to invoke the method on a secondary execution unit, as for execution unit B in the example. In the example, execution unit B is free, and object 2 method 2 52 will be invoked as required. If execution unit B should also be busy, the messaging interface 46 , 47 , 48 of the invoking execution unit will continue hunting through its list of viable targets. This system enables the transparent implementation of load balancing between the various execution units.
[0063] Message Interface
[0064] The message interface 46 , 47 , 48 , 49 connects the messaging bus or switch fabric forming the invocation network 42 to the execution units 33 , 34 , 35 , 37 in the manner shown in FIG. 8.
[0065] On the receive side, the interface is made up of a number of components. The filtering stage 61 selects messages for individual nodes, where each processing node is assigned a unique identifier either dynamically on start-up for software or hard-wired at manufacture for fixed blocks. The buffering stage 62 then acts as a temporary store for the message, thus freeing up the switch fabric, until the execution unit is ready to consume the received message. The execution unit can alternatively mark the node as being busy, which causes all incoming messages to be blocked.
[0066] The transmit path consists of a buffer 64 and controlling logic 65 . The execution unit will generate a complete message and place it in the buffer. The control section will then attempt to send that message over the switch fabric. After the destination address is transmitted, the receiving node will signal back the acceptance or rejection (blocking) of the message. As previously described for message load balancing, messages can be rejected (blocked) if the receiving node is busy.
[0067] If the message is accepted, then the complete message is transmitted across the bus or switch. If the message is rejected, then repeated attempts will normally be made to transmit the message to the list of viable targets. If required, attempts to retransmit the message in this way may be aborted if a suitable target does not become available within a specified time. In this case, a higher level software entity may be notified in order to initiate any corrective action which may be required.
[0068] Shared Memory System
[0069] The shared memory 32 in this arrangement provides a common address space to all the execution units. All the execution units will potentially be running in parallel and all accessing shared memory, so the execution units use acknowledged memory transfers, and the shared memory system provides arbitration between the competing demands for memory bandwidth. A number of known examples of system-on-chip busses would be suited to this application.
[0070] Support For The Runtime Environment
[0071] There are a number of functions that the operating system traditionally performs that have high performance penalties. Specifically, memory allocation and event timers benefit greatly from a hardware accelerated approach. Additionally, programming semaphores are best centralised for efficient operation. These runtime support functions are provided as common resources connected to the hardware and software execution units via the on-chip invocation network 42 .
[0072] Memory Allocation
[0073] A memory allocation unit 38 enables the shared memory 32 to be allocated to objects as and when required. Multiple memory areas may be employed for the total shared memory with each memory allocator 38 controlling allocation for a defined sub-area of the shared memory 32 . The memory allocator 38 keeps track of the used and free memory space in ordered lists, changing each list depending on the requests for new memory or the release of used memory.
[0074] An object requiring an area of shared memory makes its request by passing a message detailing the amount of memory required to the memory allocator 38 which responds with a message detailing the position of the allocated memory space. By implementing the memory allocators 38 in hardware and interfacing to them over the invocation network 42 , any object in hardware or software has the ability to create new object data areas 31 a , 31 b , 31 c , 31 d , 31 e , 31 f in shared memory 32 .
[0075] The freeing of the shared memory is also handled by the runtime support, and as memory blocks are freed, known techniques for reducing memory fragmentation may be applied.
[0076] Event Timers
[0077] In event driven systems, it is important to be able to schedule multiple events at arbitrary times in the future. Hardware support for this which utilises the invocation network to inform objects of time-outs using call-back can improve performance.
[0078] Whilst in software systems, the number of timers which may be created is almost limitless, the resources required to service those timers can become excessive. Although hardware timers do not consume processor runtime resources, there is a cost associated with the hardware used to implement multiple physical timers that may or may not be required in the life time of the system.
[0079] The proposed arrangement addresses this issue by having a central hardware resource which does not consume software resources implemented in a software manner and providing an almost limitless number of timers 40 . This component utilises the sending and receiving of messages as a mechanism to gain access to the timer functions.
[0080] The hardware resource is implemented as an ordered list of actions stored in local memory or a cached area of shared memory, where the availability of memory is the only limit to the number of timers that can be constructed. An action is created when the object requiring the timer functionality passes a message to the timer component and the action is then stored at the appropriate position in the ordered list. Each action has a unique identification which allows an individual object to maintain multiple timers.
[0081] When the timeout for an action occurs, a callback message is returned to the object which created the action, indicating that the timer has expired. Therefore the runtime resources required to implement a timer are minimised and the number of timers available to the system is only limited by the allocated memory.
[0082] Semaphores
[0083] Semaphores may be used in the system to protect particular object data 31 a, 31 b, 31 c , 31 d , 31 e , 31 f from corruption when multiple execution units 33 , 34 , 35 may be attempting to access object data at the same time. Although the use of semaphores is sometimes undoubtedly necessary, over reliance on semaphore synchronisation may imply that object abstraction or ordering is non-optimal.
[0084] Traditionally, semaphores have been implemented in multiprocessor systems by using atomic memory accesses to monitor and update semaphore flags in a shared memory area. However, with the various methods associated with the same object now communicating via an integrated messaging system i.e. the invocation network 42 , implementing semaphores via hardware messaging is a more efficient and elegant approach.
[0085] Objects requiring access protection can request a new semaphore when they are created by sending a message to the semaphore manager 39 . The new semaphore has a unique identification which is used by all methods which need to gain access to the protected data. Any object requesting access does so via a message to the semaphore manager 39 which specifies the unique semaphore identification.
[0086] A returning message grants access once the semaphore manager 39 has set the semaphore, thus denying access for other methods. If the semaphore is already set, the request is queued until the semaphore is released by the preceding requester. Once granted, semaphores must be released on completion of the critical section of execution by sending a release semaphore message. Semaphores must be removed via an appropriate message as the object which caused their creation is destroyed.
[0087] By using this central resource to construct, control and remove semaphores, any object methods implemented in either software or hardware may have controlled access to other object routines or data structures.
[0088] Counters
[0089] Conventionally, multiple counters have been implemented in either software or hardware within the same limitations as previously described for timers. In addition, since a number of counters can be used for gathering different statistical information, this information is normally accessed in counter groups—that is, related counter values should be requested or updated together in a contemporaneous manner. This avoids instances where one counter value may be processed whilst another related counter is being incremented, leading to inaccurate results. By implementing such counters as a central resource accessed via messages, all update or read operations from any method of any object can be implemented in an atomic manner.
[0090] Execution Units
[0091] The execution units 33 , 34 , 35 , 37 are blocks that implement the message and shared memory interfaces and provide at least one object method implementation. The block must be capable of interpreting messages and returning acknowledgement messages as well as implementing the required method(s).
[0092] In many cases the execution unit will be implemented using a microcoded engine 34 , processor 35 or other sequenced controller. However this is not a strict requirement and some method implementations may be based around state machines, pipelines or other fixed configurations 33 . Such fixed configuration method implementations may be hardwired at the time of manufacture or implemented using embedded programmable logic such as programmable logic arrays (PLAs) or field programmable gate arrays (FPGAs).
[0093] When implementing methods on embedded processors, the interface between the software method definitions 45 a , 45 b and the hardware runtime support 37 may exist in a number of forms. At the most basic level, a set of libraries may provide a direct link between the software method(s) and the hardware runtime support. A more sophisticated software environment may use a real time operating system (RTOS) kernel with support for interrupt-driven multitasking to concurrently execute a number of methods. For a host processor running a fully featured operating system, this capability is extended such that conventional software applications may multitask alongside the executing methods.
[0094] A key feature of the proposed embodiments is the heterogeneous nature of the execution units, and the fact that they can all communicate together in a single system using the unified messaging and shared memory interfaces.
[0095] This provides overall system performance improvements, as signal processing methods can be implemented on dedicated digital signal processors (DSPs), network protocol based methods can be implemented on network processors and specialised tasks can be implemented using custom microcoded engines or directly in hardware. This ensures that there are no restrictions on how or where a method is implemented, allowing all method implementations to employ the best type of execution unit for their algorithmic properties.
[0096] Software Mapping
[0097] The process of mapping the high level description of the application is achieved using software tools to examine the application code and find within this code method invocations which refer to hardware accelerated methods or methods implemented on different execution units. These invocations are then modified to replace the standard calling mechanism with one that generates method invocation messages for sending across the invocation network 42 .
[0098] This transformation may be implemented in a number of ways—the preferred approach is to perform the modifications at the link stage. The linker has access to the software method identifiers and method invocation parameters, and can use these to perform the necessary changes.
[0099] Alternatively dynamic linking could be implemented as part of the runtime environment.
[0100] Data I/O Method Implementations
[0101] Within the framework illustrated in FIG. 3, it is often necessary to provide object methods which are capable of transferring data from an external data input interface 71 to an object data area in memory or object data from memory to an external data output interface 72 . Typically, the methods in question will form part of a non-conglomerate object as shown in FIG. 9 and they will perform the function of transferring data to and from shared memory 32 . However, this does not preclude the implementation of an input/output I/O interface 73 on a conglomerate object whereby data is transferred to and from the local memory area of the relevant execution unit.
[0102] The way in which an object input method interacts with other object methods within the system is shown in FIG. 10. In this case, a thread of execution is initiated in the data input method by the arrival of an input data event 81 . The type of this input data event is application specific, examples of which may be a data packet in communications systems, a sensor reading in control systems or a data sample in signal processing systems.
[0103] On receiving an input data event, the data input method behaves as a constructor method, requesting 82 a suitable area of shared memory for storage of the object data from the memory manager. Once the memory area has been allocated 83 , the data input method sets up the memory area to be consistent with the requirements of the data object class and the input data is placed in the object data area 85 , thus completing the object creation process. The data input method will then invoke 86 another method on the object in order to initiate the processing or other manipulation 87 of the object, according to the requirements of the system.
[0104] An example output data method is shown in FIG. 11, which is similar to the input data method previously described. Once a data processing method 91 has completed, and the data is ready for output, an output data method is invoked 92 . Output data methods may be conventional methods which simply transmit the data part of the object 93 on the output port. Alternatively, they may be destructor methods which will automatically destroy the object once it has been transmitted.
[0105] In the example illustrated in FIG. 11, an output method which is a destructor method is shown. Once the output method is invoked, the data is transmitted 93 before the deallocate memory method is invoked 94 on the memory management object. This frees up 95 the memory area associated with the object so that it may be reused for the creation of new object data areas. Once memory deallocation has been acknowledged 96 , the data output method has successfully destroyed 97 the object and the associated thread of execution is terminated.
[0106] It is not a requirement of the invention that messages be passed over a physically separate set of interfaces from the memory transactions, only that the method invocation mechanism is logically distinct from the mechanism used to access object data in the shared memory area. This encompasses implementations of the invention which provide physically separate method invocation and memory systems, a single combined multiplexed memory and invocation network and mechanisms whereby method invocation occurs via a logically distinct area of shared memory.
[0107] Also, a partitioned shared memory area may be used where there are multiple disjoint areas of shared memory each of which is only accessible to a subset of the total number of execution units within the system. The specific embodiment as described above being a special case whereby the number of shared memory areas is one.
[0108] Additionally load balancing and fault tolerance between processing objects can be achieved through monitoring not only the busy state of the target objects, but by using a more complicated matrix of parameters, such as average idle times, free threads, heartbeats or other indication of activity.
[0109] Although the invention has been shown and described with respect to a best mode embodiment thereof, it should be understood by those skilled in the art that the foregoing and various other changes, omissions and additions in the form and detail thereof may be made therein without departing from the scope of the invention as claimed. | There is provided an object orientated heterogeneous multi-processor architecture comprising a plurality of execution units amongst which object methods are distributed, a run-time support, a shared memory for storing object data and which is accessible by the execution units and by the run-time support, and an invocation network for carrying method invocation messages between execution units and/or between the run-time support. Object based source code is distributable across a variable number of the execution units. The invocation network is logically distinct from any mechanism for accessing the object data stored in the shared memory. Also provided are methods of operating the heterogeneous multi-processor architecture and of managing communications in an object orientated program execution environment. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 09/387,304 filed Aug. 11, 1999 (now issued as U.S. Pat. No. 6,095,262), and therethrough claims priority from provisional application Ser. No. 60/098,442 filed Aug. 31, 1998.
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates generally to the drilling of oil and gas wells, or similar drilling operations, and in particular to orientation of tooth angles on a roller cone drill bit.
BACKGROUND: ROTARY DRILLING
Oil wells and gas wells are drilled by a process of rotary drilling, using a drill rig such as is shown in FIG. 10 . In conventional vertical drilling, a drill bit 10 is mounted on the end of a drill string 12 (drill pipe plus drill collars), which may be more than a mile long, while at the surface a rotary drive (not shown) turns the drill string, including the bit at the bottom of the hole.
Two main types of drill bits are in use, one being the roller cone bit, an example of which is seen in FIG. 11 . In this bit a set of cones 16 (two are visible) having teeth or cutting inserts 18 are arranged on rugged bearings on the arms of the bit. As the drill string is rotated, the cones will roll on the bottom of the hole, and the teeth or cutting inserts will crush the formation beneath them. (The broken fragments of rock are swept uphole by the flow of drilling fluid.) The second type of drill bit is a drag bit, having no moving parts, seen in FIG. 12 .
Drag bits are becoming increasingly popular for drilling soft and medium formations, but roller cone bits are still very popular, especially for drilling medium and medium-hard rock. There are various types of roller cone bits: insert-type bits, which are normally used for drilling harder formations, will have teeth of tungsten carbide or some other hard material mounted on their cones. As the drill string rotates, and the cones roll along the bottom of the hole, the individual hard teeth will induce compressive failure in the formation.
The bit's teeth must crush or cut rock, with the necessary forces supplied by the “weight on bit” (WOB) which presses the bit down into the rock, and by the torque applied at the rotary drive. While the WOB may in some cases be 100,000 pounds or more, the forces actually seen at the drill bit are not constant: the rock being cut many have harder and softer portions (and may break unevenly), and the drill string itself can oscillate in many different modes. Thus the drill bit must be able to operate for long periods under high stresses in a remote environment.
When the bit wears out or breaks during drilling, it must be brought up out of the hole. This requires a process called “tripping”: a heavy hoist pulls the entire drill string out of the hole, in stages of (for example) about ninety feet at a time. After each stage of lifting, one “stand” of pipe is unscrewed and laid aside for reassembly (while the weight of the drill string is temporarily supported by another mechanism). Since the total weight of the drill string may be hundreds of tons, and the length of the drill string may be tens of thousands of feet, this is not a trivial job. One trip can require tens of hours and is a significant expense in the drilling budget. To resume drilling the entire process must be reversed. Thus the bit's durability is very important, to minimize round trips for bit replacement during drilling.
BACKGROUND: DRILL STRING OSCILLATION
The individual elements of a drill string appear heavy and rigid. However, in the complete drill string (which can be more than a mile long), the individual elements are quite flexible enough to allow oscillation at frequencies near the rotary speed. In fact, many different modes of oscillation are possible. (A simple demonstration of modes of oscillation can be done by twirling a piece of rope or chain: the rope can be twirled in a flat slow circle, or, at faster speeds, so that it appears to cross itself one or more times.) The drill string is actually a much more complex system than a hanging rope, and can oscillate in many different ways; see WAVE PROPAGATION IN PETROLEUM ENGINEERING , Wilson C. Chin, (1994).
The oscillations are damped somewhat by the drilling mud, or by friction where the drill pipe rubs against the walls, or by the energy absorbed in fracturing the formation: but often these sources of damping are not enough to prevent oscillation. Since these oscillations occur down in the wellbore, they can be hard to detect, but they are generally undesirable. Drill string oscillations change the instantaneous force on the bit, and that means that the bit will not operate as designed. For example, the bit may drill oversize, or off-center, or may wear out much sooner than expected. Oscillations are hard to predict, since different mechanical forces can combine to produce “coupled modes”; the problems of gyration and whirl are an example of this.
BACKGROUND: ROLLER CONE BIT DESIGN
The “cones” in a roller cone bit need not be perfectly conical (nor perfectly frustroconical), but often have a slightly swollen axial profile. Moreover, the axes of the cones do not have to intersect the centerline of the borehole. (The angular difference is referred to as the “offset” angle.) Another variable is the angle by which the centerline of the bearings intersects the horizontal plane of the bottom of the hole, and this angle is known as the journal angle. Thus as the drill bit is rotated, the cones typically do not roll true, and a certain amount of gouging and scraping takes place. The gouging and scraping action is complex in nature, and varies in magnitude and direction depending on a number of variables.
Conventional roller cone bits can be divided into two broad categories: Insert bits and steel-tooth bits. Steel tooth bits are utilized most frequently in softer formation drilling, whereas insert bits are utilized most frequently in medium and hard formation drilling.
Steel-tooth bits have steel teeth formed integral to the cone. (A hardmetal is typically applied to the surface of the teeth to improve the wear resistance of the structure.) Insert bits have very hard inserts (e.g. specially selected grades of tungsten carbide) pressed into holes drilled into the cone surfaces. The inserts extend outwardly beyond the surface of the cones to form the “teeth” that comprise the cutting structures of the drill bit.
The design of the component elements in a rock bit are interrelated (together with the size limitations imposed by the overall diameter of the bit), and some of the design parameters are driven by the intended use of the product. For example, cone angle and offset can be modified to increase or decrease the amount of bottom hole scraping. Many other design parameters are limited in that an increase in one parameter may necessarily result in a decrease of another. For example, increases in tooth length may cause interference with the adjacent cones.
BACKGROUND; TOOTH DESIGN
The teeth of steel tooth bits are predominantly of the inverted “V” shape. The included angle (i.e. the sharpness of the tip) and the length of the tooth will vary with the design of the bit. In bits designed for harder formations the teeth will be shorter and the included angle will be greater. Gage row teeth (i.e. the teeth in the outermost row of the cone, next to the outer diameter of the borehole) may have a “T” shaped crest for additional wear resistance.
The most common shapes of inserts are spherical, conical, and chisel. Spherical inserts have a very small protrusion and are used for drilling the hardest formations. Conical inserts have a greater protrusion and a natural resistance to breakage, and are often used for drilling medium hard formations.
Chisel shaped inserts have opposing flats and a broad elongated crest, resembling the teeth of a steel tooth bit. Chisel shaped inserts are used for drilling soft to medium formations. The elongated crest of the chisel insert is normally oriented in alignment with the axis of cone rotation. Thus, unlike spherical and conical inserts, the chisel insert may be directionally oriented about its center axis. (This is true of any tooth which is not axially symmetric.) The axial angle of orientation is measured from the plane intersecting the center of the cone and the center of the tooth.
BACKGROUND: ROCK MECHANICS AND FORMATIONS
There are many factors that determine the drillability of a formation. These include, for example, compressive strength, hardness and/or abrasivity, elasticity, mineral content (stickiness), permeability, porosity, fluid content and interstitial pressure, and state of under-ground stress.
Soft formations were originally drilled with “fish-tail” drag bits, which sheared the formation away. Roller cone bits designed for drilling soft formations are designed to maximize the gouging and scraping action. To accomplish this, cones are offset to induce the largest allowable deviation from rolling on their true centers. Journal angles are small and cone-profile angles will have relatively large variations. Teeth are long, sharp, and widely-spaced to allow for the greatest possible penetration. Drilling in soft formations is characterized by low weight and high rotary speeds.
Hard formations are drilled by applying high weights on the drill bits and crushing the formation in compressive failure. The rock will fail when the applied load exceeds the strength of the rock. Roller cone bits designed for drilling hard formations are designed to roll as close as possible to a true roll, with little gouging or scraping action. Offset will be zero and journal angles will be higher. Teeth are short and closely spaced to prevent breakage under the high loads. Drilling in hard formations is characterized by high weight and low rotary speeds.
Medium formations are drilled by combining the features of soft and hard formation bits. The rock breaks away (is failed) by combining compressive forces with limited shearing and gouging action that is achieved by designing drill bits with a moderate amount of offset. Tooth length is designed for medium extensions as well. Drilling in medium formations is most often done with weights and rotary speeds between that of the hard and soft formations. Area drilling practices are evaluated to determine the optimum combinations.
BACKGROUND: ROLLER CONE BIT INTERACTION WITH THE FORMATION
In addition to improving drilling efficiency, the study of bottom hole patterns has allowed engineers to prevent detrimental phenomena such as those known as tracking, and gyration. The impressions a tooth makes into the formation depend largely on the design of the tooth, the tangential and radial scraping motions of the tooth, the force and speed with which the tooth impacts the formation, and the characteristics of the formation. Tracking occurs when the teeth of a drill bit fall into the impressions in the formation formed by other teeth at a preceding moment in time during the revolution of the drill bit. Gyration occurs when a drill bit fails to drill on-center. Both phenomena result in slow rates of penetration, detrimental wear of the cutting structures and premature failure of bits. Other detrimental conditions include excessive uncut rings in the bottom hole pattern. This condition can cause gyration, result in slow rates of penetration, detrimental wear of the cutting structures and premature failure of the bits. Another detrimental phenomenon is bit lateral vibration, which can be caused by radial force imbalances, bit mass imbalance, and bit/formation interaction among other things. This condition includes directional reversals and gyration about the hole center often known as whirl. Lateral vibration results in poor bit performance, overgage hole drilling, out-of-round, or “lobed” wellbores, and premature failure of both the cutting structures and bearing systems of bits. (Kenner and Isbell, DYNAMIC ANALYSIS REVEALS STABILITY OF ROLLER CONE ROCK BITS, SPE 28314, 1994).
BACKGROUND: BIT DESIGN
Currently, roller cone bit designs remain the result of generations of modifications made to original designs. The modifications are based on years of experience in evaluating bit records, dull bit conditions, and bottom hole patterns.
One method commonly used to discourage bit tracking is known as a staggered tooth design. In this design the teeth are located at unequal intervals along the circumference of the cone. This is intended to interrupt the recurrent pattern of impressions on the bottom of the hole. Examples of this are shown in U.S. Pat. No.4,187,922 and UK application 2,241,266.
BACKGROUND: SHORTCOMINGS OF EXISTING BIT DESIGNS
The economics of drilling a well are strongly reliant on rate of penetration. Since the design of the cutting structure of a drill bit controls the bit's ability to achieve a high rate of penetration, cutting structure design plays a significant role in the overall economics of drilling a well. Current bit designs have not solved the issue of tracking. Complex mathematical models can simulate bottom hole patterns to a limited extent, but they do not suggest a solution to the ever-present problem of tracking. The known angular orientations of teeth designed to improve tooth impact strength leave excessive uncut bottom hole patterns and do not solve the problem of tracking. The known angular orientations of teeth designed to increase bottom hole coverage, fail to optimize tooth orientation and do not solve the problem of tracking. Staggered tooth designs do not prevent tracking of the outermost rows of teeth. On the outermost rows of each cone, the teeth are encountering impressions in the formation left by teeth on other cones. The staggered teeth are just as likely to track an impression as any other tooth. Another disadvantage to staggered designs is that they may cause fluctuations in cone rotational speed, resulting in fluctuations in tooth impact force and increased bit vibration. Bit vibration is very harmful to the life of the bit and the life of the entire drill string.
BACKGROUND: CUTTING STRUCTURE DESIGN
In the publication A NEW WAY TO CHARACTERIZE THE GOUGING - SCRAPING ACTION OF ROLLER CONE BITS (Ma, Society of Petroleum Engineers No. 19448, 1989), the author determines that a tooth in the first (heel or gage) row of the drill bit evaluated contacts the formation at −22 degrees (measured with respect to rotation of the cone about its journal) and begins to separate at an angle of −6 degrees. The author determines that the contacting range for the second row of the same cone is from −26 degrees to 6 degrees. The author states that “because the crest of the chisel inserts are always in the parallel direction with the generatrix of the roller cone . . . radial scraping will affect the sweep area only slightly.” The author concludes that scraping distance is a more important than the velocity of the cutter in deternining performance.
In U.S. Pat. No. 5,197,555, Estes discloses a roller cone bit having opposite angular axial orientation of chisel shaped inserts in the first and second rows of a cone. This invention is premised on the determination that inserts scrape diagonally inboard and either to the leading side (facing in the direction of rotation) or to the trailing side (facing opposite to the direction of rotation). It is noted that the heel row inserts engage the formation to the leading side, while the second row inserts engage the formation to the trailing edge. In one embodiment, the inserts in the heel row are axially oriented at an angle between 30 degrees and 60 degrees, while the inserts in the second row are axially oriented between 300 degrees and 330 degrees. This orientation is designed to provide the inserts with a higher resistance to breakage. In an alternative embodiment, the inserts in the heel row are oriented at an axial angle between 300 degrees and 330 degrees, while the inserts in the second row are axially oriented between 30 degrees and 60 degrees. This orientation is designed to provide the inserts with a broader contact area with the formation for increased formation removal, and thereby an increased rate of penetration of the drill bit into the formation.
SUMMARY: ROLLER-ONE BITS, SYSTEMS, DRILLING METHODS, AND DESIGN METHODS WITH OPTIMIZATION OF TOOTH ORIENTATION
The present application describes bit design methods (and corresponding bits, drilling methods, and systems) in which tooth orientation is optimized jointly with other parameters, using software which graphically displays the linearized trajectory of each tooth row, as translated onto the surface of the cone. Preferably the speed ratio of each cone is precisely calculated, as is the curved trajectory of each tooth through the formation. However, for quick feedback to a design engineer, linear approximations to the tooth trajectory are preferably displayed.
The disclosed innovations, in various embodiments, provide one or more of at least the following advantages:
The disclosed methods provide a very convenient way for designers to take full advantage of the precision of a computer-implemented calculation of geometries. (The motion over hole bottom of roller cone bit teeth is so complex that only a complex mathematical model and associated computer program can provide accurate design support.)
The disclosed methods provide convenient calculation of tooth trajectory over the hole bottom during the period when the tooth engages into and disengages from the formation.
The disclosed methods permit the orientation angle of teeth in all rows to be accurately determined based on the tooth trajectory.
The disclosed methods permit the influence of tooth orientation changes on bit coverage ratio over the hole bottom to be accurately estimated and compensated.
The disclosed methods also permit designers to optimally select different types of teeth for different rows, based on the tooth trajectory.
The following patent application describes roller cone drill bit design methods and optimizations which can be used separately from or in synergistic combination with the methods disclosed in the present application. That application, which has common ownership, inventorship, and effective filing date with the present application. is: application Ser. No. 09/387,737, filed Aug. 31, 1999, now U.S. Pat. No. 6,213,225 entitled “Force-Balanced Roller-Cone Bits, Systems, Drilling Methods, and Design Methods” (atty. docket No. SC-9825), claiming priority from U.S. provisional application Ser. No. 60/098,466 filed Aug. 31, 1998.
That nonprovisional application, and its provisional priority application, are both hereby incorporated by reference.
BRIEF DESCRIPTION OF THE DRAWING
The disclosed inventions will be described with reference to the accompanying drawings, which show important sample embodiments of the invention and which are incorporated in the specification hereof by reference, wherein:
FIGS. 1A-1C shows a sample embodiment of a bit design process, using the teachings of the present application.
FIG. 2 shows the tangential and radial velocity components of tooth trajectory, viewed through the cutting face (i.e. looking up).
FIGS. 3A, 3 B, 3 C, and 3 D show plots of planar tooth trajectories for teeth in four rows of a single cone, referenced to the XY coordinates of FIG. 2 .
FIGS. 4A and 4B show tangential and radial distances, respectively, for the four tooth trajectories shown in FIGS. 3A-3D.
FIG. 5 is a sectional view of a cone (normal to its axis), showing how the tooth orientation is defined.
FIG. 6 shows time-domain plots of tooth tangential speed, for the five rows of a sample cone, over the duration of the trajectory for each row.
FIGS. 7A and 7B show how optimization of tooth orientation can perturb the width of uncut rings on the hole bottom.
FIGS. 8A and 8B show how optimization of tooth orientation can disturb the tooth clearances.
FIGS. 9A, 9 B and 9 C show the screen views which a skilled bit designer would see, according to some embodiments of the invention, while working on a bit optimization which included optimization of tooth orientation.
FIG. 10 shows a drill rig in which bits optimized by the teachings of the present application can be advantageously employed.
FIG. 11 shows a conventional roller cone bit, and FIG. 12 shows a conventional drag bit.
FIG. 13 shows a sample XYZ plot of a non-axisymmetric tooth tip.
FIG. 14 shows axial and sectional views of the i-th cone, and illustrates the enumeration of rows and teeth.
FIGS. 15A-15D show how the planarized tooth trajectories vary as the offset is increased.
FIGS. 16A-16D show how the ERSD and ETSD values vary for all rows of a given cone as offset is increased.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The numerous innovative teachings of the present application will be described with particular reference to the presently preferred embodiment (by way of example, and not of limitation).
Overview of Sample Design Process
FIGS. 1A-1C show a sample embodiment of a bit design process, using the teachings of the present application. Specifically, FIG. 1A shows an overview of the design process, and FIGS. 1B and 1C expand specific parts of the process.
First, the bit geometry, rock properties, and bit operational parameters are input (step 102 ). Then the 3 D tooth shape, cone profile, cone layout, 3 D cone, 3 D bit, and 2 D hole profile are displayed (step 104 ).
Since there are two types of rotation relevant to the calculation of the hole bottom (cone rotation and bit rotation), transformation matrices from cone to bit coordinates must be calculated (step 106 ). (See FIG. 1B.) The number of bit revolutions is input (step 108 ), and each cone is counted (step 110 ), followed by each row of teeth for each cone (step 112 ). Next, the type of teeth of each row is identified (step 114 ), and the teeth are counted (step 116 ). Next, a time interval delta is set (step 118 ), and the position of each tooth is calculated at this time interval (step 120 ). If a given tooth is not “cutting” (i.e., in contact with the hole bottom), then the algorithm continues counting until a cutting tooth is reached (step 122 ). The tooth trajectory, speed, scraping distance, crater distribution, coverage ratio and tracking ratios for all rows, cones, and the bit are calculated (step 124 ). This section of the process (depicted in FIG. 1B) gives the teeth motion over the hole bottom, and displays the results (step 126 ).
Next the bit mechanics are calculated. (See FIG. 1C.) Again transformation matrices from cone to bit coordinates are calculated (step 128 ), and the number of bit revolutions and maximum time steps, delta, are input (step 130 ). The cones are then counted (step 132 ), the bit and cone rotation angles are calculated at the given time step (step 134 ), and the rows are counted (step 136 ). Next, the 3 D tooth surface matrices for the teeth on a given row are calculated (step 138 ). The teeth are then counted (step 140 ), and the 3 D position of the tooth on the hole bottom is calculated at the given time interval (step 142 ). If a tooth is not cutting, counting continues until a cutting tooth is reached (step 144 ). The cutting depth, area, volume and forces for each tooth are calculated, and the hole bottom model is updated (based on the crater model for the type of rock being drilled). Next the number of teeth cutting at any given time step is counted. The tooth force is projected into cone and bit coordinates, yielding the total cone and bit forces and moments. Finally the specific energy of the bit is calculated (step 146 ).
Finally, all results are outputted (step 148 ). The process can then be reiterated if needed.
Four Coordinate Systems
Four coordinate systems are used, in the presently preferred embodiment, to define the crest point of a tooth in three dimensional space. All the coordinate system obey the “Right Hand Rule”. These coordinate systems—tooth, cone, bit, and hole—are described below.
Local Tooth Coordinates
FIG. 13 shows a sample XYZ plot of a tooth tip (in tooth local coordinates). Tooth coordinates will be indicated here by the subscript t. (Of course, each tooth has its own tooth coordinate system.) The center of the X t Y t Z t coordinate system, in the presently preferred embodiment, is located at the tooth center. The coordinate of a tooth's crest point P t will be defined by parameters of the tooth profile (e.g. tooth diameter, extension, etc.).
Cone Coordinates
FIG. 14 shows axial and sectional views of the i-th cone, and illustrates the enumeration of rows and teeth. Cone coordinates will be indicated here by the subscript c. The center of the cone coordinates is located in the center of backface of the cone. The cone body is fixed with respect to these coordinates, and hence THESE COORDINATES ROTATE WITH THE CONE. (Of course, each cone has its own cone coordinate system.) The axis Z c coincides with the cone axis, and is oriented towards to the bit center. Cone axes Y c and X c , together with axis Z c , follow the right hand rule. As shown in FIG. 13, four parameters are enough to completely define the coordinate of the crest point of a tooth on cone profile. These four parameters are H c , R c , φ c and φ c . For all the teeth on the same row, H c , R c , and φ c are the same.
Bit Coordinates
Similarly, a set of bit axes X b Y b Z b , indicated by the subscript b, is aligned to the bit. The bit is fixed with respect to these coordinates, and hence THESE COORDINATES ROTATE WITH THE BIT. Axis Z b preferably points toward the cutting face, and axes X b and Y b are normal to Z b (and follow the right-hand rule).
Hole Coordinates
The simplest coordinate system is defined by the hole axes X h Y h Z h , which are fixed in space. Note however that axes Z b and Z h may not be coincident if the bit is tilted. FIG. 2 shows the tangential and radial velocity components of tooth trajectory, viewed through the cutting face (i.e. looking up). Illustrated is a small portion of a tooth trajectory, wherein a tooth's crest (projected into an X h Y h plane which approximates the bottom of the hole) moves from point A to point B, over an arc distance ds and a radial distance dr.
Transformations
Since all of these coordinate systems are xyz systems, they can be interrelated by simple matrix transformations.
Both the bit and the cones are rotating with time. In order to calculate the position on hole bottom where the crest point of a tooth engages into formation, and the position that the crest point of a tooth disengages from formation, all the teeth positions at any time must be described in hole coordinate system XhYhZh.
The transformation from tooth coordinates X t Y t Z t , to cone coordinates X c Y c Z c can be defined by a matrix Rtc, which is a matrix function of teeth parameters:
Rtc=f ( H c , R c , θ c , φ c ),
so that any point P t in X t Y t Z t can be transformed into local cone coordinates X c Y c Z c by:
P c =R tc *P t .
At time t=0, it is assumed that the plane X c O c Z c is parallel to the bit axis. At time t, the cone has a rotation angle λ around its negative axis (−Z c ). Any point on the cone moves to a new position due to this rotation. The new position of P c in X c Y c Z c can be determined by combining linear transforms.
The transform matrix due to cone rotation is R cone :
R cone =cos(λ) I +(1-cos(λ)) NcNc ′+sin(λ) Mc,
where N c is the rotation vector and M c is a 3*3 matrix defined by N c .
Therefore, the new position P crot of P c due to cone rotation is:
P
crot
=R
cone
*P
c
Let R cb1 , R cb2 , and R cb3b be respective transformation matrices (for cones 1, 2, and 3) from cone coordinate to bit coordinates. (These matrices will be functions of bit parameters such as pin angle, offset, and back face length.) Any point P ci in cone coordinates can then be transformed into bit coordinates by:
P b =R cbi *P ci +P c0i for i= 1, 2, or 3,
where P c0i is the origin of cone coordinates in the bit coordinate system.
The bit is rotating around its own axis. Let us assume that the bit axes and hole axes are coincident at time t=0. At time t, the bit has a rotation angle β. The transform matrix due to bit rotation is:
Rbh =cos(β) I +(1−cos(β)) NbNb ′+sin(β) Mb
where Nb is the rotation vector and Mb is a 3*3 matrix defined by Nb. Therefore, any point Pb in bit coordinate system can be transformed into the hole coordinate system X h Y h Z h by:
Ph=Rbh*Pb.
Therefore, the position of the crest point of any tooth at any time in three dimensional space has been fully defined by the foregoing seven equations. In order to further determine the engage and disengage point the formation is modeled, in the presently preferred embodiment, by multiple stepped horizontal planes. (The number of horizontal planes depends on the total number of rows in the bit.) In this way, the trajectory of any tooth on hole bottom can be determined.
Calculation of Trajectories in Bottomhole Plane
With the foregoing transformations, the trajectory of the tooth crest across the bottom of the hole can be calculated. FIGS. 3A, 3 B, 3 C, and 3 D show plots of planar tooth trajectories, referenced to the hole coordinates X h Y h , for teeth on four different rows of a particular roller cone bit. The teeth on the outermost row (first row) scrapes toward the leading side of the cone. Its radial and tangential scraping distances are similar, as can be seen by comparing the first bar in FIG. 4A with the first bar in FIG. 4 B. However for teeth on the second row the radial scraping motion is much larger than the tangent motion. The teeth on the third row scrape toward the trailing side of the cone, and the teeth on the forth row scrape toward the leading side of the cone.
FIGS. 4A and 4B show per-bit-revolution tangential and radial distances, respectively, for the four tooth trajectories shown in FIGS. 3 A- 3 D. Note that, in this example, the motion of the second row is almost entirely radial, and not tangential.
Projection of Trajectories into Cone Coordinates
The tooth trajectories described above are projected on the hole bottom which is fixed in space. In this way it is clearly seen how the tooth scrapes over the bottom. However for the bit manufacturer or bit designer it is necessary to know the teeth orientation angle on the cone coordinate, in order either to keep the elongate side of the tooth perpendicular to the scraping direction (for maximum cutting rate in softer formations) or to keep the elongate side of the tooth in line with the scraping direction (for durability in harder formations). To this end the tooth trajectories are projected to the cone coordinate system. Let P 1 ={x 1 , y 1 , Z 1 } c and P 2 ={x 2 , Y 2 , z 2 } c be the engage and disengage points on cone coordinate system, respectively, and approximate the tooth trajectory P 1 -P2 as a straight line. Then the scraping angle in cone coordinates is:
R s ={square root over ((x 2 +L −x 1 +L ) 2 +L +(y 1 +L +y 2 +L ) 2 +L )}
and γ s = tan - 1 ( R s z 2 - z 1 )
The teeth can then be oriented appropriately with respect to this angle gamma. For example, for soft formation drilling the tooth would preferably be oriented so that its broad side is perpendicular to the scraping direction, in order to increase its rate of rock removal. In this case, the direction γ c of the elongate crest of the tooth, in cone coordinates, is normal to γ s , i.e. γ c =γ s +π/2. Conversely, for drilling harder formations with a chisel-shaped tooth it might be preferable to orient the tooth with minimum frontal area in the direction of scraping, i.e. with y c =y s .
Derivation of Equivalent Radial and Tangential Scraping
There are numerous parameters in roller cone design, and experienced designers already know, qualitatively, that changes in cone shape (cone angle, heel angle, third angle, and oversize angle) as well as offset and journal angle will affect the scraping pattern of teeth in order to get a desired action-bottom. One problem is that it is not easy to describe a desired action-on-bottom quantitatively. The present application provides techniques for addressing this need.
Two new parameters have been defined in order to quantitatively evaluate the cone shape and offset effects on tooth scraping motion. Both of these parameters can be applied either to a bit or to individual cones.
(1) Equivalent Tangent Scraping Distance (ETSD) is equal to the total tangent scraping distance of all teeth on a cone (or bit) divided by the total number of the teeth on the cone (or bit).
(2) Equivalent Radial Scraping Distance (ERSD) is equal to the total radial scraping distance of all teeth on a cone (or bit) divided by the total number of the teeth on the cone (or bit).
Both of these two parameters they have much more clear physical meaning than the offset value and cone shape.
Surprisingly, the arcuate (or bulged) shape of the cone primarily affects the ETSD value, and the offset determines the ERSD value. Also surprisingly, the ERSD is not equal to zero even at zero offset.
In other words, the teeth on a bit without offset may still have some small radial scraping effects.
The radial scraping direction for all teeth is always toward to the hole center (positive). However, the tangential scraping direction is usually different from row to row.
In order to use the scraping effects fully and effectively, the leading side of the elongated teeth crest should be orientated at an angle to the plane of the cone's axis, which is calculated as described above for any given row.
FIG. 2 shows the procedure in which a tooth cuts into (point A) and out (point B) the formation. Due to bit offset, arcuate cone shape and bit and cone rotations, the motion from A to B can be divided into two parts: tangent motion ds and radial motion dr. Notice the tangent and radial motions are defined in hole coordinate system XhYh. Because ds and dr vary from row to row and from cone to cone, we derive an equivalent tangent scraping distance (ETSD) and an equivalent radial scraping distance (ERSD) for a whole cone (or for an entire bit).
For a cone, we have ETSD = ∑ j Nr ds j Nt j Nc and ERSD = ∑ j Nr dr j Nt j Nc
where Nc is the total tooth count of a cone and Nr is the number of rows of a cone.
Similarly for a bit, we have ETSD = ∑ i 3 ∑ j Nr ds ij Nt ij Nb and ERSD = ∑ i 3 ∑ j Nr dr ij Nt ij Nb
where Nb is the total tooth count of the bit.
FIGS. 15A-15D show how the planarized tooth trajectories vary as the offset is increased. These figures clearly show that with the increase of the offset value, the radial scraping distance is increased. Surprisingly, the radial scraping distance is not equal to zero even if the offset is zero. This is due to the arcuate shape of the cone.
FIGS. 16A-16D show how the ERSD and ETSD values vary for all rows of a given cone as offset is increased. From these Figures, it can be seen that the tangent scraping distance of the gage row, while very small compared to other rows but is not equal to zero. It means that there is a sliding even for the teeth on the driving row. This fact may be explained by looking at the tangent speed during the entry and exit of teeth into and out of the rock. (FIG. 6 shows time-domain plots of tooth tangential speed, for the five rows of a sample cone, over the duration of the trajectory for each row.) During the cutting procedure the tangent speed is not equal to zero except for one instant. Because the sliding speed changes with time, the instantaneous speed is not the best way to describe the teeth/rock interaction.
Note that the tangent scraping directions are different from row to row for the same cone. FIG. 5 is a sectional view of a cone (normal to its axis), showing how the tooth orientation is defined in the present application: the positive direction is defined as the same direction as the bit rotation. This means that the leading side of tooth on one row may be different from that on another row.
The ERSD increases almost proportionally with the increase of the bit offset. However, ERSD is not zero even if the bit offset is zero. This is because the radial sliding speed is not always zero during the procedure of tooth cutting into and cutting out the rock.
Calculation of Uncut Rings, and Row Position Adjustment
FIGS. 7A and 7B show how optimization of tooth orientation can perturb the width of uncut rings on the hole bottom. The width of uncut rings is one of the design constraints: a sufficiently narrow uncut ring will be easily fractured by adjacent cutter action and mud flows, but too large an uncut ring will slow rate of penetration. Thus one of the significant teachings of the present application is that tooth orientation should not be adjusted in isolation, but preferably should be optimized jointly with the width of uncut rings.
Interference Check
Another constraint is tooth interference. In the crowded geometries of an optimized roller cone design, it is easy for an adjustment to row position to cause interference between cones. FIGS. 8A and 8B graphically show how optimization of tooth orientation can disturb the tooth clearances. Thus optimization of tooth orientation is preferably followed by an interference check (especially if row positions are changed).
Iteration
Preferably multiple iterations of the various optimizations are used, to ensure that the various constraints and/or requirements are all jointly satisfied according to an optimal tradeoff.
Graphic Display
The scraping motion of any tooth on any row is visualized on the designer's computer screen. The bit designer has a chance to see quantitatively how large the motion is and in which direction if bit geometric parameters like cone shape and offset are changed.
FIGS. 9A, 9 B and 9 C show the screen views which a skilled bit designer would see, according to some embodiments of the invention, while working on a bit optimization which included optimization of tooth orientation. These three views show representations of tooth orientation and scraping direction for each tooth row on each of the three cones. This simple display allows the designer to get a feel for the effect of various parameter variations
Calculation of Cone/Bit Rotation Ratio
The present application also teaches that the ratio between the rotational speeds of cone and bit can be easily checked, in the context of the detailed force calculations described above, simply by calculating the torques about the cone axis. If these torques sum to zero (at a given ratio of cone and bit speed), then the given ratio is correct. If not, an iterative calculation can be performed to find the value of this ratio.
However, it should be noted that the exact calculation of the torque on the cones is dependent on use of a solid-body tooth model, as described above, rather than a mere point approximation.
Previous simulations of roller cone bits have assumed that the gage row is the “driving” row, which has no tangential slippage against the cutting face. However, this is a simplification which is not completely accurate. Accurate calculation of the ratio of cone speed to bit speed shows that it is almost never correct, if multiple rows of teeth are present, to assume that the gage row is the driver.
Changes in the tooth orientation angle will not themselves have a large immediate effect on the cone speed ratio. However, the tooth orientation affects the width of uncut rings, and excessive uncut ring width can require the spacing of tooth rows to be changed. Any changes in the spacing of tooth rows will probably affect the cone speed ratio.
Definitions:
Following are short definitions of the usual meanings of some of the technical terms which are used in the present application. (However, those of ordinary skill will recognize whether the context requires a different meaning.) Additional definitions can be found in the standard technical dictionaries and journals.
Drag bit: a drill bit with no moving parts that drills by intrusion and drag.
Mud: the liquid circulated through the wellbore during rotary drilling operations, also referred to as drilling fluid. Originally a suspension of earth solids (especially clays) in water, modern “mud” is a three-phase mixture of liquids, reactive solids, and inert solids.
Nozzle: in a passageway through which the drilling fluid exits a drill bit, the portion of that passageway which restricts the cross-section to control the flow of fluid.
Orientation: the angle of rotation with which a non-axisymmetric tooth is inserted into a cone. Note that a tooth which is axisymmetric (e.g. one having a hemispherical tip) cannot have an orientation.
Roller cone bit: a drilling bit made of two, three, or four cones, or cutters, that are mounted on extremely rugged bearings. Also called rock bits. The surface of each cone is made up of rows of steel teeth (generally for softer formations) or rows of hard inserts (typically of tungsten carbide) for harder formations.
According to a disclosed class of innovative embodiments, there is provided: A method of designing a roller cone bit, comprising the steps of: adjusting the orientation of at least one tooth on a cone, in dependence on an expected trajectory of said tooth through formation material at the cutting face, in dependence on an estimated ratio of cone rotation to bit rotation; recalculating said ratio, if the location of any row of teeth on said cone changes during optimization; recalculating the trajectory of said tooth in accordance with a recalculated value of said cone speed; and adjusting the orientation of said tooth again, in accordance with a recalculated value of said tooth trajectory.
According to another disclosed class of innovative embodiments, there is provided: A method of designing a roller cone bit, comprising the steps of: calculating the trajectory of at least one tooth on each cone through formation material at the cutting face; and jointly optimizing both the orientations of said teeth and the width of uncut rings on said cutting face, in dependence on said trajectory.
According to another disclosed class of innovative embodiments, there is provided: A method of designing a roller cone bit comprising the steps of: a) adjusting the orientation of at least one row of teeth on a cone, in dependence on an expected trajectory of said tooth through formation material at the cutting face; b) calculating the width of uncut rings of formation material, in dependence on the orientation of said row of teeth, and adjusting the position of said row of teeth in dependence on said calculated width; and c) recalculating the rotational speed of said cone, if the position of said row is changed, and accordingly recalculating said trajectory of teeth in said row.
According to another disclosed class of innovative embodiments, there is provided: A method of designing a roller cone bit, comprising the steps of: calculating the respective trajectories, of at least two non-axisymmetric teeth in different rows of a roller cone bit, through formation material at the cutting face; and graphically displaying, to a design engineer, both said trajectories and also respective orientation vectors of said teeth, as the engineer adjusts design parameters.
According to another disclosed class of innovative embodiments, there is provided: A method of designing a roller cone bit, comprising the steps of: calculating the curved trajectory of a non-axisymmetric tooth through formation material at the cutting face, as the bit and cones rotate; calculating a straight line approximation to said curved trajectory; and orienting said tooth with respect to said approximation, and not with respect to said curved trajectory.
According to another disclosed class of innovative embodiments, there is provided: A roller cone drill bit designed by any of the methods described above, singly or in combination.
According to another disclosed class of innovative embodiments, there is provided: A rotary drilling system, comprising: a roller cone drill bit designed by any of the methods described above, singly or in combination, a drill string which is mechanically connected to said bit; and a rotary drive which rotates at least part of said drill string together with said bit.
According to another disclosed class of innovative embodiments, there is provided: A method for rotary drilling, comprising the actions of: applying weight-on-bit and rotary torque, through a drill string, to a drill bit designed in accordance with any of the methods described above, singly or in combination.
Modifications and Variations
As will be recognized by those skilled in the art, the innovative concepts described in the present application can be modified and varied over a tremendous range of applications, and accordingly the scope of patented subject matter is not limited by any of the specific exemplary teachings given.
For example, the various teachings can optionally be adapted to two-cone or four-one bits.
In the example of FIGS. 9A-9C the crest profiles of all rows except the gage rows are shown as identical (and their crest orientations are indicated by simple ellipses). However, this is not necessary: optionally the designer can be allowed to plug in different tooth profiles for different rows, and the optimization routines can easily substitute various tooth profiles as desired. In particular, various tooth shapes can be selected from a library of profiles, to fit the scraping motion of each row.
In one contemplated class of alternative embodiments, the orientations of teeth can be perturbed about the optimal value, to induce variation between the gage rows of different cones (or within an inner. row of a single cone), to provide some additional resistance to tracking.
Of course the bit will also. normally contain many other features besides those emphasized here, such as gage buttons, wear pads, lubrication reservoirs, etc. etc.
Additional general background, which helps to show the knowledge of those skilled in the art regarding implementations and the predictability of variations, may be found in the following publications, all of which are hereby incorporated by reference: APPLIED DRILLING ENGINEERING , Adam T. Bourgoyne Jr. et al., Society of Petroleum Engineers Textbook series (1991), OIL AND GAS FIELD DEVELOPMENT TECHNIQUES: DRILLING , J.-P. Nguyen (translation 1996, from French original 1993), MAKING HOLE (1983) and DRILLING MUD (1984), both part of the Rotary Drilling Series, edited by Charles Kirkley.
None of the description in the present application should be read as implying that any particular element, step, or function is an essential element which must be included in the claim scope: THE SCOPE OF PATENTED SUBJECT MATTER IS DEFINED ONLY BY THE ALLOWED CLAIMS. Moreover, none of these claims are intended to invoke paragraph six of 35 USC section 112 unless the exact words “means for” are followed by a participle. | A novel and improved roller cone drill bit and method of design are disclosed. A roller cone drill bit for drilling through subterranean formations having an upper connection for attachment to a drill string, and a plurality cutting structures rotatably mounted on arms extending downward from the connection. A number of teeth are located in generally concentric rows on each cutting structure. The actual trajectory by which the teeth engage the formation is mathematically determined. A straight-line trajectory is calculated based on the actual trajectory. The teeth are positioned in the cutting structures such each tooth having a designed engagement surface is oriented perpendicular to the calculated straight-line trajectory. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 11/529,046 filed Sep. 28, 2006, the contents of which is expressly incorporated herein by reference in its entirety.
FIELD
This application relates generally to power management of remote sensor devices.
BACKGROUND
Some remote sensor devices are capable of communicating a signal to a primary device indicating when the remote device is low on power. Upon receiving such a signal, the primary device may warn its user that the remote device is low on power, and thus enable the user to recharge or replace the battery of the remote device before the remote device actually runs out of power. One example of such a system is a computer that employs wireless user input (UI) devices, such as a wireless mouse or keyboard. When such UI devices are low on power, a signal is communicated to the computer's processor indicating the low power condition, and the computer then displays a message to the user warning of the same. If the user subsequently fails to replace or recharge the battery promptly, the remote device continues to operate normally until it has completely run out of power. At such time, the remote device becomes incapable not only of performing its intended function but also of informing the primary device of the reason it has become inoperable.
SUMMARY
According to one aspect of the present invention, a method involves us of a first device comprising a sensor configured to sense a stimulus experienced by the first device, a controller configured to process data received from the sensor and thereby obtain processed sensor data, a transmitter configured to wirelessly transmit the processed data from the first device to a second device, and a battery configured to supply power to at least the controller and the transmitter. The first device is operated in a first operational mode in which the sensor, the controller, and the transmitter are used at least occasionally to obtain and transmit processed data to the second device. When it is determined that the battery is in a low power condition, the first device is operated in a second operational mode wherein the sensor, controller, and transmitter are not used to obtain and transmit processed sensor data to the second device, but wherein the first device at least occasionally transmits a signal to the second device that indicates a low power condition of the battery.
According to another aspect, an apparatus comprises a sensor, a controller, a transmitter, and a battery. The sensor is configured to sense a stimulus experienced by the apparatus. The controller is configured to process data received from the sensor and thereby obtain processed sensor data. The transmitter is configured to wirelessly transmit the processed sensor data from the apparatus to another device. The battery is configured to supply power to at least the controller and the transmitter. The apparatus is configured to operate in a first operational mode when a determination is made that the battery is not in a low power condition, and to operate in a second operational mode when a determination is made that the battery is in a low power condition. In the first operational mode, the sensor, the controller, and the transmitter are used at least occasionally to obtain and transmit processed sensor data to the other device. In the second operational mode, the sensor, controller, and transmitter do not obtain and transmit processed sensor data to the other device, but the apparatus at least occasionally transmits a signal to the other device that indicates a low power condition of the battery.
According to another aspect, a method involves use of a first device comprising a sensor configured to sense a stimulus experienced by the first device, a controller configured to process data received from the sensor and thereby obtain processed sensor data, a transmitter configured to wirelessly transmit the processed data from the first device to a second device, a receiver configured to receive data transmitted wirelessly from the second device to the first device, and a battery configured to supply power to at least the controller, the transmitter, and the receiver. The first device is operated in a first operational mode in which the sensor, the controller, and the transmitter are used at least occasionally to obtain and transmit processed data to the second device, and in which the receiver is used at least occasionally to receive data transmitted wirelessly from the second device. When it is determined that the battery is in a low power condition, the first device is operated in a second operational mode wherein the receiver is not used to receive data transmitted wirelessly from the second device, but wherein the transmitter is used at least occasionally to transmit a signal to the second device that indicates a low power condition of the battery.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an illustrative embodiment of a remote sensor apparatus; and
FIGS. 2-4 are flow charts showing examples of routines that may be executed by the controller shown in FIG. 1 .
DETAILED DESCRIPTION
In some embodiments, upon detecting a “low power” condition of a remote sensor device, the mode of operation of the remote device may be changed so as to substantially reduce its rate of power consumption. The remote device may then be allowed to perform only a limited set of functions, and may continue to transmit a “low power” signal to a primary device for an extended period of time in spite of its decreased functionality. In certain embodiments, the remote device may be configured so that the only function it performs while in its “low power” mode of operation is the transmission of a signal to the primary device informing the primary device of its “low power” condition. In some embodiments, the capacity or usage of the battery may additionally be monitored to determine when the battery is soon to be in a “low power” condition and a signal is transmitted indicating such to be the case, thus enabling the user to be warned that the battery is “running low and needs to be replaced soon,” or to be provided with some similar message or indication. Should the user fail to replace the battery before the “low power” condition is actually reached, the device will not simply cease working, but will change modes of operation so as to substantially reduce its power consumption and will continue to inform the user of the “lower power” condition of the battery. Accordingly, unlike with prior art remote sensor devices that cease all operations after they run out of power, a user of a device like that disclosed herein will not be left guessing as to whether the system including the remote device ceased working because the remote device ran out of power or because of some other reason, such as failure of one or more other components of the remote device or failure of one or more components of the receiving device.
FIG. 1 is a block diagram of an example of a remote sensor device 100 that may be employed in connection with certain embodiments of the invention. As shown, the device 100 may include a controller 102 , a sensor 104 , a battery 106 , a memory 108 , a transmitter 110 , an antenna 112 , and a battery monitoring unit 114 . A remote sensor device 100 configured generally as shown in FIG. 1 can be configured in any of a number of ways and can be used for any of a number of purposes, and the invention is not limited to any particular type of device or use thereof. In certain embodiments, for example, the remote sensor device 100 may comprise an ambulatory device that is mounted on or within a shoe or otherwise supported by a person to monitor activity of the person while he or she is walking or running or is otherwise in locomotion on foot. Examples of such devices are disclosed, for example, in U.S. Pat. Nos. 6,611,789; 6,305,221; 6,301,964; 6,298,413; 6,032,108; 6,018,705; 5,955,667; 4,578,769; and 4,371,945, the entire contents of each of which is incorporated herein by reference. Alternatively, the remote sensor device 100 may comprise, for example, a wireless mouse or a wireless keyboard for a computer, or any other device capable of sensing one or more stimuli and communicating data concerning a sensed stimulus to another device via a wireless communications link.
The sensor 104 may comprise any device that is capable of sensing an external stimulus, and the invention is not limited to the use of any particular type of sensor. It may, for example, comprise an accelerometer such as that disclosed in U.S. Pat. No. 6,336,365, which is incorporated herein by reference in its entirety, or may comprises any of the sensors disclosed in U.S. Pat. Nos. 6,611,789; 6,305,221; 6,301,964; 6,298,413; 6,032,108; 6,018,705; 5,955,667; 4,578,769; and 4,371,945. Alternatively, it may comprise, as but a few examples, another type of accelerometer, a vibration sensor, a temperature sensor, a humidity sensor, a light sensor, an audio detector, an electrical or magnetic field sensor, etc. Any number of sensors of the same type, or any combination of different types of sensors may be employed in various embodiments. It should be appreciated that the sensor 104 may additionally comprise certain signal processing elements, e.g., one or more amplifiers, buffers, filters, etc., arranged to condition a signal generated by a transducer, e.g., an accelerometer such as that disclosed in U.S. Pat. No. 6,336,365, prior to providing the signal to the controller 102 .
The controller 102 may, for example, comprise one or more processors capable of receiving and processing data from the sensor 104 . Any type or number of controllers may be employed and the invention is not limited to the use of a controller of any particular type or configuration. As shown in FIG. 1 , the controller 102 may have an associated memory 108 in which data and instructions accessed by the controller 102 may be stored to enable the controller 102 to execute various routines. The memory 108 may be embodied either separately or integrally with the controller 102 . Examples of routines that may be performed by the controller 102 in connection with certain embodiments of the invention are described below in connection with FIGS. 2-4 .
The transmitter 110 and associated antenna 112 may take on any of numerous forms and may be employed, for example, to wirelessly transmit processed data from the sensor to another device, e.g., a wristwatch, a portable music player, a computer, etc. In some embodiments, a receiver (not shown) may additionally be employed in the device 100 to receive incoming wireless signals, or a transceiver, that can both transmit and receive wireless signals, may instead be used.
The battery 106 may be responsible for supplying power to all of the components in the remote device 100 . It may take on any of numerous forms, and the invention is not limited to the use of a battery of any particular type or configuration. The specific type and energy capacity of the battery may be chosen based on the application at hand. In an embodiment in which the battery is used to power a shoe-mounted remote sensor device that is used to monitor performance parameters of a user in locomotion on foot, the battery may, for example, be a CR2032 Lithium coin cell having a capacity of 200 milliamp hours (mAh).
The battery monitoring unit 114 may comprise any known device or circuit capable of monitoring the remaining capacity of the battery 106 . Such devices and the techniques they employ are well understood in the art and thus will not be described herein. As discussed in more detail below, in some embodiments, a “low power” condition of the battery 106 may be determined not by directly monitoring a state of the battery, but rather based upon monitoring or estimating the cumulative power consumption of the components in the device 100 . Accordingly, at least in some embodiments, a battery monitoring unit 114 like that shown would not be required.
FIG. 2 shows an illustrative example of a routine 200 that may be executed by the controller 102 shown in FIG. 1 . As noted above, instructions for the routine 200 may, for example, be stored in the memory 108 associated with the controller 102 . As shown, the routine 200 may begin at a step 202 wherein the controller is “initialized.” Such initialization may occur, for example, when a new battery 106 is installed in the device 100 , in response to a user command, or by some other mechanism.
After initialization, the routine 200 proceeds to steps 204 and 206 , wherein one or more sensors and controllers are placed in an “active” mode to enable them to perform their data accumulation and processing functions. In some embodiments, for example, an accelerometer and a processor may be caused to begin actively accumulating and analyzing data concerning footsteps taken by a user in locomotion on foot. It should be appreciated, however, that in certain embodiments, the step 204 may involve the activation of one or more signal processing elements, e.g., amplifiers, buffers, filters, etc., associated with a transducer (not shown) in addition to or in lieu of activating the transducer itself. It should further be appreciated that, in some embodiments a sensor may be employed that does not itself consume power, and the step 204 may thus be omitted in such embodiments.
After “activating” the sensor 104 (if necessary) and the controller 102 , the routine 200 proceeds to a step 208 , wherein data accumulated by the sensor may be processed in an appropriate fashion. As discussed in more detail below, in connection with the step 208 , processed data from the sensor 104 may be transmitted wirelessly to another device via the transmitter 110 and antenna 112 of the device 100 .
At the step 210 , the routine 200 next determines whether any new data is being accumulated by the sensor 104 . Such a determination may, for example, involve an assessment of whether the sensor 104 has ceased generating a signal or data for more than a particular period of time, e.g., several seconds. When it is determined that the sensor has ceased accumulating data, the routine 200 proceeds to steps 212 and 214 , wherein the one or more sensors and controllers may be taken out of their “active” mode and placed in a “sleep” mode for power preservation purposes. As noted above, in embodiments in which the sensor 104 does not require power in order to be “active,” the step 212 may be omitted.
After placing the device 100 in a “sleep” mode, the routine 200 waits at a step 216 until a determination is made that the device should “wake up” to begin actively processing and accumulating data once again. The determination of whether and when to wake up may be made, for example, by monitoring an output of the sensor 104 (or a transducer included therein) for activity, in a response to a user input, e.g., depression of a “start” button, or by any other mechanism. In embodiments in which a sensor is used to monitor locomotion of a person on foot, the “wake up” determination 216 may be made, for example, by employing a low-power comparator (not shown) to monitor the output of a transducer. In embodiments in which an accelerometer that does not consume power, e.g., the accelerometer disclosed in U.S. Pat. No. 6,336,365, is employed as the transducer, the power consumption of the device 100 in the “sleep” mode may thus be substantially limited to only the power consumption of such a comparator. It should be appreciated that in addition to such an automated “wake up” function, the device 100 may additionally or alternatively comprise one or more user input devices, e.g., switches or pushbuttons, that may be manipulated to cause the device 100 to “wake up.” Furthermore, one or more user input devices may additionally or alternatively be provided that can be manipulated to cause the device 100 to be put into a “sleep” mode, or even to cause the device to be powered down completely so that even the automated “wake up” function is disabled until further user input is provided.
Referring again to FIG. 2 , when at the step 210 (discussed above) it is determined that new data is being accumulated by the sensor 104 , the routine 200 proceeds to a step 218 , wherein it is determined whether the battery 106 is in a “low power” condition, e.g., by determining whether the capacity of the battery 106 has been depleted below a particular level. When, it is determined that the battery is not in a “low power” condition, the routine 200 returns to the step 208 , wherein the sensor data continues to be accumulated and processed. When, it is determined that the battery 106 is in a “low-power” condition, however, the routine 200 proceeds to a step 220 , wherein the device is placed in a “life support mode” (discussed in more detail below in connection with FIG. 4 .) In alternative embodiments, the step 218 may additionally or alternatively be performed at other points in the routine 200 , and it is not critical that it be performed immediately after determining whether new sensor data is being accumulated. For example, in some embodiments, the step 218 may additionally or alternatively be performed immediately after the step 206 and/or between the steps 208 and 210 .
The determination of whether the battery 106 is in a “low power” condition may be made in any of a number of ways, and the invention is not limited to any particular technique or mechanism for making such a determination. In some embodiments, the remaining capacity of the battery 106 may be measured directly by the battery monitoring unit 114 capacity monitoring techniques that may be employed by the battery monitoring unit are well known in the art and thus will not be described in further detail. The determination of whether the battery 106 is in a “low power” condition may thus be made by evaluating whether the measured remaining capacity is below a particular threshold. In other embodiments, the controller 102 or some other device may additionally or alternatively track the cumulative power consumption of the various components in the device 100 , or estimate such consumption based on cumulative time of use in various modes, and the determination of whether the battery 106 is in a “low power” condition may thus be made by evaluating whether the determined total power usage since installation of a new battery is above a particular threshold.
No matter how the “low power” determination is made, a threshold level may be set that allocates the total power capacity of the battery 106 between a first period in which the device 100 is in its “operational mode” and a second, subsequent period during which the device 100 is in its “life support mode,” so as to achieve desired operational objectives. For instance, if it is desired that the device 100 be capable of transmitting a “life support beacon” once every hour for a period of two years after the primary functionality of the device has been shut down, then the threshold level may be set accordingly. The portion of the total capacity of the battery 106 that is to be used for “life support” may be calculated, for example, by multiplying the desired total number of “life support beacons” by the power consumed by each beacon transmission. The allocation of the total capacity of the battery may also, of course, take into account the desired lifetime of the device 100 in its “operational mode.”
It should be appreciated that, in addition to determining whether the “low power” condition discussed above has been reached, the capacity or usage of the battery may additionally be monitored to determine when the battery is soon to be in the “low power” condition. This may be achieved, for example, by employing the same technique used to monitor for the “low power” condition, but using a slightly higher or lower threshold. When such a determination is made, a signal may be transmitted via the transmitter 110 and antenna 112 that informs the primary device that the battery 106 is running low and needs to be replaced. The message or indication provided to the user as a result of such a signal may either be the same as that provided in response to the low power beacon, or may be a different message. For example, in response to a signal indicating the battery is approaching the “low power” condition, a message may be displayed informing the user the battery is “running low,” whereas in response to a signal indicating the “low power” condition has already been reached, the message may inform the user that the battery is “out of power.”
FIG. 3 shows an illustrative example of the routine 208 ( FIG. 2 ) that may be employed by a device that senses activity of a person in locomotion on foot, for example, by employing one or more accelerometers to monitor motion of the person. In the illustrative example shown, the routine 208 begins at a step 302 , wherein “foot contact times” of a person, i.e., amounts of time during in which a person's foot is on the ground during respective footsteps taken by the person, are determined by examining the output of the sensor 104 . Based on the measured foot contact times, the routine 208 may then calculate performance parameters such as pace, distance traveled, speed, etc., (step 304 ), and subsequently transmit such information to another device via the transmitter 110 and antenna 112 (step 306 ). The routine 208 shown in FIG. 3 is, of course, but only one example of a routine that may employed to accumulate, process, and transmit sensor data to another device. Other examples of additional or alternative routines that may be employed in connection with various embodiments of the invention are disclosed in U.S. Pat. Nos. 6,611,789; 6,305,221; 6,301,964; 6,298,413; 6,032,108; 6,018,705; 5,955,667; 4,578,769; and 4,371,945, discussed above. A radio transmission protocol such as that disclosed in U.S. Patent Application Publication No. 2002/0091785A1, or any other suitable protocol, may be employed to communicate data and/or commands between the device 100 and the other device. In some embodiments, a routine 208 such as that illustrated in FIG. 3 will be performed only when the device 100 is in its “operational mode,” and may, for example, require the battery 106 to supply approximately two milliamps of current to the various components of the device 100 .
FIG. 4 shows an illustrative example of a routine that may be employed when the device 100 is placed in a “life support mode” (step 200 in FIG. 2 ). In the example shown, the only activity for which the device 100 is allowed to consume power is to transmit a “life support beacon,” e.g., a signal indicating that the device has run out of power, at least occasionally. Such a “life support” routine may, for example, require the battery 106 to supply approximately 6 micro-amps of current to the various components of the device 100 . It should be appreciated, however, that the device 100 may alternatively be configured so that some additional level of activity beyond the transmission of a “life support beacon” may be permitted. All that is important is that the modality of the device 100 be changed in some way so that certain power-consuming activities cease when the device 100 enters the “life support mode.” In some embodiments, when the device 100 is placed in its “life support mode,” the modality of the radio transmission protocol employed by the device 100 may also changed so as to further minimize its power consumption. For example, in embodiments in which a two-way radio transmission protocol is employed to wirelessly communicate data between the device 100 and another device when the device 100 is in its “operational mode,” the device 100 may further conserve power by switching to a one-way radio transmission protocol, e.g., to allow only the transmission of a “life-support beacon” but not the receipt of incoming messages, upon entering its “life support mode.”
In the example of FIG. 4 , the routine 220 first involves de-activating the sensor 104 and/or the processor 102 (steps 402 and 404 ) so that the controller 102 ceases processing data accumulated by the sensor 104 and transmitting processed sensor data via the transmitter 110 and antenna 112 . In the example shown, the controller 102 may be deactivated except to the extent necessary to transmit a life support beacon each time the device 100 “wakes up” for such a purpose. As noted above, some embodiments may employ a sensor 104 that need not be deactivated, and the step 402 need not be employed in such circumstances.
The “wake up” step 408 may involve, for example, waking up once every minute, once every ten minutes, once every hour, etc., with a period depending upon the type of sensor that is employed and the use to which it is being put. Additionally or alternatively, the step 408 may involve sensing an external stimulus, for example, sensing motion that indicates that perhaps a user is attempting to put the device to use. In some embodiments, for example, an output of an accelerometer may be monitored to determine whether the signal exceeds a certain threshold. In certain such embodiments, power consumption in the “life support mode” may be limited significantly by basing the wake up decision in whole or in part upon the output of a low-power comparator that compares the output of an accelerometer such as that disclosed in U.S. Pat. No. 6,336,365 to a threshold voltage.
The step 408 may additionally or alternatively involve the manipulation of a user input mechanism, e.g., a pushbutton, that may cause the device to transmit a beacon upon activation of the mechanism, or may simply allow the device to “wake up” in response to a sensed stimulus and/or periodically (as discussed above), for some period of time after the mechanism has been activated. In some embodiments, a low-power receiver may additionally or alternatively be used to determine whether and when another device is attempting to communicate with the remote device 100 , and the “life support beacon” may be transmitted upon detection of such a communication attempt. Any combination of the above techniques may also be employed. For example, the device may attempt to send a message once every minute during time periods after a pushbutton has been depressed or after a determination is made that the device 100 is in motion.
Having described several embodiments of the invention in detail, various modifications and improvements will readily occur to those skilled in the art. Such modifications and improvements are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only, and is not intended as limiting. The invention is limited only as defined by the following claims and the equivalents thereto. | One disclosed method involves providing a first device comprising a sensor configured to sense a stimulus experienced by the first device, a controller configured to process data received from the sensor and thereby obtain processed sensor data, a transmitter configured to wirelessly transmit the processed data, and a battery configured to supply power to at least the controller and the transmitter. The first device is operated in a first operational mode in which the sensor, the controller, and the transmitter are used at least occasionally to obtain and transmit processed data. When the battery is in a low power condition, the first device is operated in a second operational mode wherein the sensor, controller, and transmitter are not used to obtain and transmit processed sensor data, but wherein the first device at least occasionally transmits a signal that indicates a low power condition of the battery. | 0 |
BACKGROUND
1. Technical Field
The present disclosure relates to screwdrivers, and particularly to a screwdriver with changeable driver head.
2. Description of Related Art
A conventional screwdriver is integrally formed with a specific driver head, which can be any of many types and sizes. Because types and sizes of screwdrivers are different from one another, a user usually needs to buy many screwdrivers to handle different tasks. It is quite inconvenient to store or carry these screwdrivers. Therefore, a screwdriver with replaceable driver heads sharing one handle was invented. However, to change driver heads, an operator needs to grasp the handle of the screwdriver with one hand, and change the head with the other hand, which can be extremely inconvenient because two hands are required.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a first exemplary embodiment of a screwdriver.
FIG. 2 is an exploded, isometric view of the screwdriver of FIG. 1 .
FIG. 3 is a schematic diagram, showing inner parts of the screwdriver of FIG. 1 .
FIG. 4 is a schematic diagram showing inner parts of a second exemplary embodiment of a screwdriver.
DETAILED DESCRIPTION
Referring to FIGS. 1 and 2 , a first exemplary embodiment of a screwdriver 1 includes a handle 2 , a resisting portion 3 , and a driver head 4 mounted to the handle 2 .
The driver head 4 includes an elongated main body 44 with a substantially polygonal-shaped cross-section, a substantially annular-shaped fixing portion, such as a fitting groove 42 defined in a first end of the main body 44 , and an operating portion 46 extending from a second end opposite to the first end of the main body 44 . In other embodiments, the fixing portion may be a protrusion or another kind of structure.
The handle 2 includes two parts 21 , and a plurality of fastening members 22 for mounting the two parts 21 together. Each part 21 has a substantially semi-circular cross-section, and includes a matching surface to match with the matching surface of the other part 21 , and a curved surface connecting opposite sides of the matching surface. Four screw holes 216 are defined in one part 21 through the matching surface and the curved surface of the part 21 , and four corresponding through holes 217 are defined in the other part 21 through the corresponding matching surface and curved surface. Each part 21 defines two substantially semicircular-shaped slots 211 and 212 , and a slot 214 with a substantially polygonal-shaped cross-section in the matching surface and symmetrically around an axis of the part 21 , extending from top to bottom of the part 21 . A rectangular-shaped slot 213 is defined in the matching surface of the part 21 , and the slot 212 and an upper part of the slot 214 are defined in a bottom of the slot 213 . A radius of the slot 211 is less than a radius of the slot 212 . Two holes 215 are defined in the bottom of the slot 213 , at opposite sides of the slot 212 .
The resisting portion 3 includes a button 31 , a substantially coin-shaped resisting member 32 , an elastic member such as a helical spring 33 , and two arms 34 . The button 31 includes a substantially cylindrical-shaped main body 312 , a substantially annular-shaped protrusion 314 formed around a bottom end of the main body 312 . A radius of the protrusion 314 is greater than the radius of the slot 211 , and less than the radius of the slot 212 . A diameter of the resisting member 32 is greater than a diameter of the spring 33 . In one embodiment, the resisting member 32 may be made of wear-resistant material, such as alloy steel material. Each arm 34 includes a slanting connection pole 343 , a stress portion 341 bent from a top end of the connection pole 343 , and a clasp 344 bent from a bottom end of the connection pole 343 , the clasp 344 substantially parallel to the stress portion 341 . Two shafts 342 extend from opposite sides of a junction between the connection pole 343 and the stress portion 341 .
Referring to FIG. 3 , in assembly, the button 31 of the main body 312 is received in the slot 211 of a first part 21 , with the protrusion 314 being received in the slot 212 of the first part 21 and resisting against a top end of the slot 212 . A top end opposite to the protrusion 314 of the button 31 extends out through the slot 211 . Each arm 34 is received in the slot 214 of the first part 21 , with one shaft 342 of the arm 34 inserted into a corresponding hole 215 of the first part 21 . The spring 33 is received in the slot 212 and below the stress portion 341 of the arm 34 , with a bottom end of the spring 33 resisting against a bottom end of the slot 212 . The resisting member 32 is mounted between a top end of the spring 33 and the stress portions 341 of the arms 34 . The two parts 21 are attached, with the matching surfaces of the two parts 21 matching with each other, the corresponding shafts 342 of the arms 34 received in the corresponding holes 215 of the second part 21 , and the through holes 217 of the second part 21 aligning with the corresponding screw holes 216 of the first part 21 . The fastening members 22 extend through the corresponding through holes 217 , to engage in the corresponding screw holes 216 , thereby fixing the two parts 21 together to form the handle 2 .
In use, an operator holds the screwdriver 1 in one hand and presses the button 31 of the main body 312 , with the protrusion 314 of the button 31 pressing the stress portions 341 of the arms 34 down. The resisting member 32 compresses the spring 33 , and the arms 34 rotate around the corresponding shafts 342 to make the clasps 344 of the arms depart from each other. Then, while still only needing to use one hand, the operator can fit the slot 214 over a driver head 4 and release the button 31 . The spring 33 then restores and the arms 34 rotate back, with the clasps 344 moving towards each other to sandwich the driver head 4 at the fitting groove 42 of the driver head 4 . Therefore, the screwdriver 1 is assembled with a driver head 4 .
When the driver head 4 needs to be detached from the screwdriver 1 , the screwdriver 1 is kept vertical. The button 31 is pressed, the stress portion 341 pushes the resisting member 32 to compress the spring 33 . The arms 34 rotate around the shaft 342 , and the clasps 344 depart from each other to release the driver head 4 . The driver head 4 overcomes friction between a wall bounding the slot 214 and the driver head 4 , to drop from the handle 2 automatically, because of gravity, and then another driver head 4 may be installed as above.
When a new driver head 4 needs to be mounted on the screwdriver 1 , the button 31 is pressed to rotate the arms 34 , with the clasps 344 departing from each other. The new driver head 4 which is kept vertical in a toolbox is inserted into the slot 214 of the handle 2 . The button 31 is released, and the spring 33 restores to rotate the arms 34 back. The clasps 344 move towards each other to clasp the driver head 4 at the fitting groove 42 .
FIG. 4 discloses a second exemplary embodiment of a screwdriver 1 . A difference between the first and the second exemplary embodiments of the screwdrivers 1 is that the second exemplary embodiment of the screwdriver 1 does not include a resisting member 32 and the spring 33 , while includes a torsion spring 35 connected between each arm 34 and the handle 2 . The torsion springs 35 provide a power to drive the clasps 344 of the arms 34 to clasp the driver head 4 firmly.
It is to be understood, however, that even though numerous characteristics and advantages of the embodiments have been set forth in the foregoing description, together with details of the structure and function of the embodiments, the disclosure is illustrative only, and changes may be made in details, especially in matters of shape, size, and arrangement of parts within the principles of the embodiments to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | A screwdriver is convenient for changing driver heads. A button is released to drive an arm of the screwdriver in a first position to grasp a fixing portion of the driver head. The button is pressed to drive the arm to rotate from the first position to a second position to deform an elastic member, with the arm releasing the driver head to make the driver head drop out of the handle. Each of the driver head can be easily mounted to the screwdriver, and detached from the screwdriver. | 1 |
RELATED APPLICATIONS
[0001] The present application claims benefit of U.S. Provisional Application No. 61/087,651 filed Aug. 8, 2008.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to ultrasound devices, and more particularly, to an ultrasound reaction chamber with temperature control.
[0003] There exist known methods of producing hydrogen. One known method of producing hydrogen may include converting fossil fuels into natural gas which may produce emissions of carbon dioxide and monoxide.
[0004] Another known method may include electrolysis of water which may use a high energy power source requiring relatively large loads of electric energy.
[0005] Another known hydrogen producing methods may involve chemically reacting metal hydrides or may involve reactions between water and alkaline metals such as potassium and sodium, either of which may result in relatively powerful exothermic reactions.
[0006] Methods employing ultrasound have gained interest because ultrasound can produce an improved yield in hydrogen from water however, ultrasonic reactions can produce high temperatures and pressures.
[0007] As can be seen, there is a need for an energy efficient system and method to control temperature in an ultrasonic environment.
SUMMARY OF THE INVENTION
[0008] In one aspect of the present invention, an ultrasound system comprises a tub including a reaction chamber; an ultrasound probe positioned at least partially within the reaction chamber; and a cooling jacket disposed around the tub operable to exchange heat between the tub and the cooling jacket.
[0009] In another aspect of the present invention, a gaseous fuel generator comprises an ultrasound tub including a reaction chamber; an ultrasound dome connected to the ultrasound tub; an adjustable ultrasound probe connected to the ultrasound dome; a gas flush port connected to the ultrasound dome; and a cooling jacket circumventing the ultrasound tub.
[0010] In another aspect of the present invention, a method of generating a gaseous fuel in an ultrasonic reaction chamber comprises flushing the ultrasonic reaction chamber with nitrogen or argon gas; removing oxygen present in the reaction chamber with the argon gas; applying an ultrasonic agitation to a bath of chemical reactants; and circulating a coolant through a cooling jacket, wherein the cooling jacket surrounds the reaction chamber.
[0011] These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 depicts a cut-away front view of an ultrasound system according to an exemplary embodiment of the present invention; and
[0013] FIG. 2 illustrates a series of steps according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
[0015] Various inventive features are described below that can each be used independently of one another or in combination with other features.
[0016] Broadly, embodiments of the present invention generally provide a jacketed ultrasound device that may produce, for example, hydrogen gas under an improved temperature control environment. In one exemplary use, the ultrasound device may be used as a gaseous fuel generator to produce hydrogen from water by the hydroxylation and oxidation of aluminum. By employment of the jacketed ultrasound device according to exemplary embodiments of the present invention, the temperature within a reaction chamber may be maintained above 32 degrees F. in the 35° F. to 37° F. range.
[0017] Referring to FIG. 1 , an ultrasound system 100 according to exemplary embodiments of the present invention is shown. The ultrasound system 100 may generally comprise a dome 120 , a tub 125 , ultrasound apparatus 105 , and a double-walled jacket 150 . In one exemplary embodiment, both the dome 120 and the tub 125 may be constructed with stainless steel or other durable materials certified to withstand pressures of 60 psi to 100 psi for use in ultrasonic applications.
[0018] The double-walled jacket 150 may be formed as two concentric walls an outer jacket wall 152 and an inner jacket wall 154 around the tub 125 . The concentric disposition of the outer jacket wall 152 and the inner jacket wall 154 may define an inner flow channel 158 and an inner flow channel 156 . The outer flow channel 156 may be defined by a space formed between the outer jacket wall 152 and the inner jacket wall 154 . The inner flow channel 158 may be defined by a space formed between the inner jacket wall 154 and the tub 125 . A fluid entrance connector 153 may be connected to the outer jacket wall 152 for permitting the introduction of a coolant into the outer flow channel 156 . A fluid exit connector 157 may be connected to the outer wall jacket 152 for permitting egress of the fluid from the double-walled jacket 150 . The double-walled jacket 150 may additionally include fluid ports 151 , 159 , and 155 for circulation of coolant through the double-walled jacket 150 . The fluid port 151 may allow fluid to enter the outer flow channel 156 from the fluid entrance connector 153 . The fluid port 159 may allow fluid to travel between the outer flow channel 156 and the inner flow channel 158 . The fluid port 155 may allow fluid to exit from the inner flow channel 158 into and out of the fluid exit connector 157 .
[0019] The dome 120 may be built according to metallurgic standards as one solid piece. The dome 120 may be composed of several parts. A piezo-electric ultrasound probe 115 may be attached to the dome 120 so that the probe 115 is centered within the dome 120 and passing through a dome lid 122 . The size of the ultrasound probe 115 may vary according to a size of the tub 125 . The dome 120 may also have two side ports; a flush port 140 and a gas port 180 . The flush port 140 may flush the reaction chamber 135 with nitrogen or argon gas. The gas port 180 may provide a conduit for releasing produced hydrogen from the ultrasound system 100 . The gas port 180 may house a temperature probe 184 , a gas analyzer 186 , and a pressure probe 188 . The temperature probe 184 may provide temperature readings of the internal environment of ultrasound system 100 . The gas analyzer 186 may provide a signal detecting the types of gasses being produced inside the ultrasound system 100 . A safety blow-off valve 182 may vent gas from within the dome 120 according to a pressure exceeding a predetermined pressure level as sensed by the pressure probe 188 .
[0020] The tub 125 may be hollow and include a reaction chamber 135 where a chemical reaction may take place. A sleeve 130 may line the interior of the tub 125 disposed between the inner jacket 154 and the reaction chamber 135 . In on embodiment, the sleeve 130 may be made from aluminum. A sealing ring 124 , such as an O-ring, may provide an hermetically sealed connection between the dome 120 and the tub 125 when the dome 120 and the tub 125 are attached to one another. It will be understood that other connections between the dome 120 and the tub 125 are contemplated such as a screw-type connection, a clamp-type connection, or a press-fit connection and that conventional locking mechanisms may be employed.
[0021] The ultrasound apparatus 105 may include an ultrasound head 110 and an ultrasound probe 115 . The ultrasound apparatus may be positioned centered within and passing through the dome 120 and may extend into the tub 125 when the dome 120 and tub 125 are attached.
[0022] An induction magnetic plate 190 may be included within the ultrasound system 100 and positioned outside of the tub 125 . The induction magnetic plate 190 may be connected to a power source (not shown) and when operated, may provide a magnetic field agitating contents held within the reaction chamber 135 .
[0023] Referring now to FIGS. 1 and 2 , in one exemplary operation, a clean sleeve 130 is positioned within the tub 125 (step 205 ) to hold a bath of chemical reactants 137 (step 210 ). In one exemplary method for producing hydrogen gas, the bath of chemical reactants 137 may comprise non-ionized distilled water, elemental aluminum, and sodium chloride may be placed into the tub 125 . The amounts and ratios of each of the chemical reactants may be based on the chemical equation in mole/grams described by
[0000] i. 3H 2 0+2Al
[0000] where, “H 2 0” represents the non ionized distilled water and “Al” represents aluminum, and the prefix numerals represent the number of moles for reactant. The amount in grams of sodium (NaCl) added to the reaction may be that related to the amount in grams of the two moles of aluminum, defined by an approximate ratio of 1:1. The particle size of the aluminum used may be in the range of 3.5 to 5.5 microns.
[0024] The dome 120 may be connected onto the tub 125 sealing the reaction chamber 135 from the environment (step 215 ). The ultrasound probe 115 may be disposed to contact the bath of chemical reactants 137 upon closing of the dome 120 . It will be understood that the ultrasound apparatus may be in fixed connection to the dome 120 or may be separable and may slide into and out from the dome lid 122 so that the draft of the ultrasound probe 115 in the bath of chemical reactants 137 may be adjusted. The nitrogen or argon gas may be introduced into the ultrasound system 100 through the flush port 140 flushing oxygen from the interior of the ultrasound system 100 (step 220 ). The ultrasound apparatus 105 may be operated causing the ultrasound probe 115 to emit sound waves agitating the bath of chemical reactants 137 (step 225 ). During agitation, sonohydrosis may occur producing OH − and H + particles from the water accelerating a chemical reaction with the aluminum resulting in free gas 3H 2 (hydrogen) and aluminum oxide (Al 2 O 3 ) as well as aluminum hydroxide among other byproducts. The hydrogen gas may be drawn out of the ultrasound system 100 through the gas port 180 where the temperature probe 184 may measure the current temperature in the ultrasound system 100 (step 230 ), the gas analyzer 186 may analyze the constituency of gasses exiting through the port 180 (step 250 ), and the pressure sensor 188 may measure the current pressure in the ultrasound system 100 (step 235 ). Thus, one may monitor the production quantity and quality of hydrogen gas produced in the ultrasound system 100 . One attribute that may need particular attention is the control of temperature in the ultrasound system 100 .
[0025] Temperature within the ultrasound system 100 may need to be controlled to produce an optimum reaction for the production of hydrogen. One exemplary operation maintains a temperature within the ultrasound system 100 within an approximate range between 35° F. to 37° F. During operation of the ultrasound apparatus 105 , the temperature within the reaction chamber may rise above a desired level caused by energy released from the chemical reactions as well as the heat generated by the energy of the ultrasound waves, which can cause the build-up of pressure in the ultrasound system 100 .
[0026] Temperature within the ultrasound system 100 may be controlled by circulating a coolant through the double-walled jacket 150 (step 245 ). Coolant, such as glycol, may be introduced through the fluid entrance connector 153 . The coolant may circulate through the outer flow channel 156 between the outer jacket 152 and the inner jacket 154 providing a first layer of cooling insulation. The coolant may continue to flow through the outer flow channel 156 and around the tub 125 until the coolant encounters the fluid port 159 allowing the coolant to enter the inner flow channel 158 between the inner jacket 154 and the tub 125 providing a second layer of cooling insulation. The coolant within the inner flow channel 158 may absorb heat from the tub 125 and carry the heated coolant out through fluid port 155 and out the fluid exit connector 157 . It will be understood that the coolant may be circulated in any direction around the tub 125 that may be desired according to the reaction desired in the ultrasound system 100 . It will also be understood that circulation of the coolant may be achieved by a pump (not shown) and re-cooling of heated coolant may be achieved by a heat exchanger (not shown) so that the coolant maybe re-circulated into the double-walled jacket 150 . As the temperature within the reaction chamber 135 rises or falls, the coolant flow may be adjusted until the temperature probe 184 registers a desirable temperature. Additionally, when the pressure sensor 188 detects a rise in pressure within the reaction chamber 135 , the temperature within the reaction chamber 135 may also rise. Thus pressure may be released from the reaction chamber 135 (step 240 ) through the blow off valve 182 until the pressure sensor 188 and temperature probe 184 register acceptable levels.
[0027] It may be appreciated that NaCl may be included into the reaction to supress passivation. As aluminum reacts with oxygen or with hydroxide (—OH), its by-products inhibit further reaction to occur, therefore stopping it. To facilitate the reaction to continue two things should happen, first increasing the surface area of the aluminum by decreasing the size of the particles (3 to 5 microns) and secondly by adding a salt like NaCl. Experimentation has shown that one preferred molar ratio was 1:1 of NaCl gram weight to the gram weight of aluminum (one mole of aluminum is approximately 54 grams).
[0028] In another exemplary embodiment, the induction magnetic plate 190 may be used to augment agitation of the bath of chemical reactants 137 . Ferrous material may be added to the bath of chemical reactants 137 . Operation of the induction magnetic plate 190 may cause movement of the ferrous material resulting in agitation of the bath of chemical reactants 137 .
[0029] As hydrogen produced by operation of the ultrasound system 100 exits via the gas port 180 , the hydrogen may be delivered to a storage tank (not shown), a hydrogen compressor (not shown) or to a fuel cell (not shown). When operation of the ultrasound apparatus 105 is terminated (step 255 ), a hydrogen gas yield may be measured for any gas that continues to be produced after the ultrasound emission stops (step 260 ). The dome 120 may be disconnected from the tub 125 and contents remaining in the reaction chamber 135 may be removed by lifting the sleeve 130 out of the tub 125 .
[0030] Experimentation employing exemplary embodiments demonstrates improved energy efficiency in operation of an ultrasound system 100 according to the present invention. It may be expected that passivation from the byproducts of the reaction between water and aluminum may inhibit the reaction from proceeding forward. In some cases, passivation may contribute to stopping the reaction entirely or slowing the reaction rate to a negligible level after a certain yield is achieved, once the emission of ultrasonic energy is terminated. Yet, experimentation using exemplary embodiments of the ultrasound system 100 has shown that once the reaction begins producing hydrogen, the reaction may become self sustained to the point that no further ultrasound may be needed to stimulate the reaction. The reaction may continue at a relatively slow rate compared to when the ultrasound apparatus 105 is powered yet, may be self sustainable.
[0031] The nature of the reaction may be considered a slow, process relative to some prior art processes. A reaction time of three or more hours under low energy may be expected according to exemplary embodiments of the present invention. Methods according to exemplary embodiments may prefer operating at relatively low energy levels of less than 50 Watts. Higher energy levels that approach the 50 Watt level may result in temperatures at the tip of the ultrasound reaching 5000 degrees Kelvin, which can make aluminum melt. An exemplary processing reaction may include a first phase, which may consist of a period of one hour and a half of processing at an 18-20 watt/Hr level. A second phase may include a half hour of processing at a 34 watt level setting. By this second phase, the concentration of output gas, such as hydrogen, that may be read on the gas analyzer 186 may reach a 9-10% yield concentration. At this point, the emission of ultrasound can optionally be stopped and the reaction may become self-sustainable. Otherwise, the process may continue under a third phase of processing.
[0032] What may be unexpected is that during the third phase of processing, a gas product may react over a four hour period, with yield concentrations of 80% of the gas product, such as hydrogen. This is in comparison to previously known methods that yielded 70% or less of a concentration. After the second phase, the reactants may become more viscose and a change of sound may be heard by an operator. The ultrasound system 100 may register drop in wattage. This may be due to an increase of viscosity in the chemical bath 137 . Thus, in order to maintain the previous energy level, the amplitude of ultrasound waves emitted should be increased (amplitude may be the % of the ultrasound apparatus 105 total output) the watts to be maintained at this point may be in the 8 to 10 Watts range. This phase of processing may be of shorter duration (2:45 to 3:30 hours) than that of the first phase of reaction, but this phase may consume more total energy over the span of the phase. What may also be surprising is that the amount of energy to start the reaction is low in nature, 8 to 10 Watts as compared to the 18-20 Watts used during the first few hours.
[0033] Still yet, what may further be unexpected is that an 80% yield concentration may result even when the ultrasound apparatus 105 is left unpowered after the second phase. During this exemplary embodiment of operation, exemplary embodiments of the ultrasound system 100 may continue reacting without the aid of ultrasonic agitation and may overcome the effects of passivation. For example, when the ultrasound apparatus 105 is powered off after the second phase, the reaction of elements in the chemical bath 137 may continue over several hours (in other words, the duration may typically be longer than 3 hours) and yet yield, for example, an 80% yield of concentration without the need for the additional energy consumed during phase 3 .
[0034] It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. | An ultrasound system is disclosed that includes a tub, a reaction chamber, an ultrasound probe positioned within the reaction chamber, and a cooling jacket surrounding the tub for exchanging heat with the tub. | 2 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates to a cathode ray tube (CRT) device provided with a deflection yoke, and particularly relates to a technique for reducing a magnetic field escaping as leakage from the deflection yoke.
(2) Related Art
In recent years, standards have been developed in Northern Europe in response to concerns about a low-frequency magnetic field given off by a CRT device. There is apprehension that such a magnetic field may affect the human body. Especially in Sweden, the standards, such as the MPR II and TCO standards, have been established with the aim of suppressing the magnetic field escaping from a deflection yoke or a horizontal deflection coil in particular. The magnetic field escaping as leakage from the deflection yoke or the horizontal deflection coil is referred to as the “magnetic field leakage” hereinafter. To meet the leakage limits prescribed by the standards, necessary measures should be taken for the CRT device to reduce the magnetic field leakage.
There have been techniques suggested in order to reduce the magnetic field leakage. As one example of such techniques, a magnetic field is generated as a “cancel magnetic field” in the direction opposite to the magnetic field escaping as leakage from the deflection yoke. For doing so, a “cancel coil” is used for generating the cancel magnetic field so as to cancel the magnetic field leakage.
A CRT device using a cancel coil is disclosed in Japanese Laid-Open Patent Application No. 3-165428 (referred to as the first prior art) and No. 6-176714 (referred to as the second prior art).
For the CRT device disclosed in the first prior art, a cancel coil for reducing the magnetic field leakage is set above an upper part of a deflection yoke and a current is supplied to the cancel coil so that a cancel magnetic field is generated. FIG. 1 shows a schematic circuit diagram of a horizontal deflection coil 27 and a cancel coil 28 of the first prior art.
As shown in FIG. 1, the horizontal deflection coil 27 and the cancel coil 28 are connected in series. By the passage of a horizontal deflection current through the cancel coil 28 as well as the horizontal deflection coil 27 , the cancel coil 28 can generate a cancel magnetic field that varies in accordance with the variations in the magnetic field leakage from the horizontal deflection coil 27 . The cancel coil 28 is positioned so that the cancel magnetic field is generated in a proper direction to cancel the magnetic field leakage.
Meanwhile, for the CRT device disclosed in the second prior art, a cancel coil for reducing the magnetic field leakage is made up of a closed-circuit winding and set at each of upper and lower parts of a CRT so as to face a deflection yoke. FIG. 2 shows a schematic circuit diagram of a horizontal deflection coil 37 and a cancel coil 38 of the second prior art.
As shown in FIG. 2, the cancel coil 38 made up of the closed-circuit winding is set facing the horizontal deflection coil 37 . With this construction, an electromotive force is produced inside the cancel coil 38 in accordance with variations in the magnetic field leakage resulting from the generation of the horizontal deflection magnetic field. By means of the electromotive force, the cancel coil 38 generates a cancel magnetic field in a proper direction so as to cancel the magnetic field leakage.
However, the CRT devices employing the techniques stated in the first and second prior arts respectively have the following problems.
As for the first prior art, the deflection current needs to pass through the cancel coil 28 that does not contribute to the horizontal deflection. Thus, power has to be unnecessarily consumed and, in addition to this, the deflection sensitivity may be deteriorated.
As for the second prior art, power does not need to be supplied to the cancel coil 38 and so the problem of the first prior art does not occur. However, the second prior art has another problem. If the magnetic field escaping as leakage from the deflection yoke is harmful to the human body, the magnetic field leakage should be reduced in front of a front panel of the CRT device, where a user is expected to be most times. However, the cancel coils 38 are set at the upper and lower parts of the CRT, facing the deflection yoke, so that the magnetic field leakage cannot be effectively reduced at a significant position where the reduction of leakage is required most. In order to reduce the magnetic field leakage at this position, the number of turns forming the cancel coil 38 may be increased. However, the increased number of turns of the cancel coil 38 may in turn adversely affect the horizontal deflection magnetic field.
Just as with the magnetic field leakage, electric field leakage is also subject to the Swedish MPR II and TCO standards. The electric field leakage is ascribable mainly to that an electric field generated due to a difference in voltage between the facing deflection coils included in the deflection yoke is given off to the outside. A technique for reducing such an electric field leakage is disclosed in, for example, Japanese Laid-Open Patent Application No. 5-207404 (referred to as the third prior art).
For the CRT device disclosed in the third prior art, a reverse voltage supplying unit is provided to supply a voltage having a reversed polarity to the waveform of the deflection voltage applied to a deflection coil. Also, an electrode is set at the top and bottom of the inner wall of the CRT at the front panel side. The reverse voltage supplying unit supplies the reverse voltage to the pair of electrodes. This enables the electrodes to generate an electric field having the reversed polarity to the VLMF (Very Low Magnetic Field) leakage (i.e., unwanted VLMF leakage). The electric field with the reversed polarity can cancel the unwanted VLMF leakage.
Using the technique of the third prior art, however, the reverse voltage supplying unit needs to be further provided. In addition to this, the magnetic field leakage cannot be reduced using this technique.
SUMMARY OF THE INVENTION
Therefore, it is a first object of the present invention to provide a CRT device that can prevent unnecessary power consumption and reduce a magnetic field leakage with a simple construction at low costs.
It is a second object of the present invention to provide a CRT device that can prevent unnecessary power consumption and reduce magnetic and electric field leakages with a simple construction at low costs.
The first object of the present invention can be achieved by a cathode ray tube device made up of: a cathode ray tube that has a front panel and a funnel; an electron gun that is set inside a neck of the funnel and projects electron beams onto an inner surface of the front panel; a deflection yoke that is set on the funnel at the neck and deflects the electron beams projected by the electron gun; and a cancel coil that has at least one closed-loop coil, makes an interlinkage with a magnetic field leakage that escapes from the deflection yoke, and generates a magnetic field in a direction so as to cancel the magnetic field leakage, wherein each closed-loop coil is set at either a first position or a second position, the first position being at a top of the cathode ray tube with a part of the closed-loop coil running along a top edge of an effective display region of the front panel, and the second position being at a bottom of the cathode ray tube with a part of the closed-loop coil running along a bottom edge of the effective display region.
With this construction, the magnetic field leakage from the CRT makes an interlinkage with the closed-loop coil, so that the magnetic field leakage can be canceled. Since the closed-loop coil is arranged along the top or bottom edge of the effective display region, the magnetic field leakage occurring at a significant position where the reduction of leakage is required most can make an interlinkage with the closed-loop coil. Consequently, the effect of canceling the magnetic field leakage can be attained at the maximum in practical terms without interfering with the image display.
It is preferable that the closed-loop coil of the cathode ray tube device further runs near right and left corners of the front panel and near an opening of the deflection yoke at a front panel side.
By doing so, the magnetic field leakage occurring in a space from the front panel to the opening of the horizontal coil at the front panel side makes an interlinkage with the closed-loop coil. As a result, the magnetic field leakage can be more effectively canceled.
The second object of the present invention can be achieved by the cathode ray tube device, wherein the closed-loop coil of the cancel coil is grounded at one point of the closed-loop coil. To be more specific, the closed-loop coil serves as a shield against the electric field leakage and so reduces the electric field escaping as leakage from the deflection yoke.
The second object of the present invention can be also achieved by a cathode ray tube device made up of: a cathode ray tube that has a front panel and a funnel; an electron gun that is set inside a neck of the funnel and projects electron beams onto an inner surface of the front panel; a deflection yoke that includes a horizontal deflection coil, and is set on the funnel at the neck and deflects the electron beams projected by the electron gun; a first coil through which a current passes, the current varying in synchronization with variations in a deflection current passing through the horizontal deflection coil; and a second coil that has at least one closed-loop coil, makes an interlinkage with any magnetic field leakage that escapes from the deflection yoke, and generates a magnetic field in a direction so as to cancel the magnetic field leakage, wherein a part of each closed-loop coil is magnetically coupled to the first coil so that an electromotive force is produced for causing a magnetic field in the same direction as the magnetic field generated through the interlinkage with the magnetic field leakage, whereby the magnetic field leakage is further canceled.
With this construction, the electromotive force is produced inside the closed-loop coil through the magnetic coupling between the closed-loop coil and the first coil through which the current varying in synchronization with the horizontal deflection current passes. By means of the electromotive force, the closed-loop coil generates the magnetic field (i.e., the cancel magnetic field) in the proper direction to further cancel the magnetic field leakage. As compared with a case where the closed-loop coil is not magnetically coupled to the first coil, a stronger cancel magnetic field can be generated. In addition, the strength of the cancel magnetic field can be easily adjusted by adjusting the strength of the magnetic coupling.
It is preferable that the part of the closed-loop coil of the cathode ray tube device is set around the correction coil for a magnetic coupling to the correction coil. By doing so, the magnetic coupling between the closed-coil loop and the differential coil can be easily achieved. The strength of the cancel magnetic field can be adjusted by changing the number of turns of the closed-loop coil to be set around the first coil.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, advantages and features of the invention will become apparent from the following description thereof taken in conjunction with the accompanying drawings which illustrate a specific embodiment of the invention. In the drawings:
FIG. 1 is a schematic circuit diagram of a horizontal deflection coil and a cancel coil of the first prior art;
FIG. 2 is a schematic circuit diagram of a horizontal deflection coil and a cancel coil of the second prior art;
FIG. 3 is a perspective external view of a CRT device of a first embodiment of the present invention;
FIG. 4 is a schematic front view of the CRT device of the first embodiment;
FIG. 5 is a rear view of the CRT device of the first embodiment;
FIG. 6 is a view to help explain the relation between a cancel magnetic field generated by closed-loop coils and a magnetic field leakage from a deflection yoke, the relation being viewed from the left side of the CRT device shown in FIG. 4;
FIG. 7 is a table showing results of measuring magnetic field leakages in the first embodiment;
FIG. 8 shows positions at which the magnetic field leakages are measured;
FIG. 9 is a table showing results of measuring electric field leakages in the first embodiment;
FIG. 10 is a perspective external view of a CRT device of a second embodiment of the present invention;
FIG. 11A is a schematic circuit diagram of a horizontal deflection coil, a differential coil, and a closed-loop coil of the CRT device of the second embodiment;
FIG. 11B shows a horizontal output circuit for supplying a horizontal deflection current to the horizontal deflection coil and the differential coil;
FIG. 12 shows that a part of the closed-loop coil is set around the differential coil in the second embodiment;
FIG. 13 shows a construction example of a magnetic coupling part between the differential coil and the closed-loop coil in the second embodiment;
FIG. 14 is a table showing results of measuring magnetic field leakages in the second embodiment; and
FIG. 15 is a table showing results of measuring electric field leakages in the second embodiment.
DESCRIPTION OF PREFERRED EMBODIMENTS
The following is a description of embodiments of the present invention, with reference to the drawings.
First Embodiment
FIG. 3 is a perspective external view of a CRT device of the first embodiment of the present invention. FIG. 4 is a schematic front view of the CRT device while FIG. 5 is a rear view of the CRT device.
As shown in FIG. 3, the CRT device of the present embodiment is composed of a CRT 1 , a deflection yoke 2 , an electron gun 11 , a reinforcing band (or, flameproof band) 3 , a first closed-loop coil 5 , and a second closed-loop coil 6 . The CRT 1 is made up of a front panel 1 a and a funnel 1 b . The deflection yoke 2 is made up of an upper (the north pole side) horizontal deflection coil 2 a , a lower (the south pole side) horizontal deflection coil 2 b , a vertical deflection coil (not illustrated), and a core (not illustrated). The electron gun 11 is set inside a neck 1 c . The reinforcing band 3 is set on the outer edge of the front panel 1 a.
The reinforcing band 3 is usually made of metal, and is set so as to securely cover a connection part of the front panel 1 a and the funnel 1 b for the purpose of protecting the CRT device from fire or heat. First to fourth ear-shaped members (simply referred to as “ears”) 4 a to 4 d are respectively formed on the four corners of the reinforcing band 3 . Note that the reinforcing band 3 and the first to fourth ears 4 a to 4 d are not illustrated in FIG. 4 for convenience of explanation.
As shown in FIG. 4 and FIG. 5, the first closed-loop coil 5 is set at an upper part of the front panel 1 a . To be more specific, the first closed-loop coil 5 is arranged just above a top edge 40 a of an effective display region 40 within which the electron beams perform raster scanning on the fluorescent screen. Simultaneously, the first closed-loop coil 5 is arranged under the first and second ears 4 a and 4 b , and near an opening of the upper horizontal deflection coil 2 a at the front panel side. Meanwhile, the second closed-loop coil 6 is set at a lower part of the front panel 1 a . To be more specific, the second closed-loop coil 5 is arranged just below a bottom edge 40 a of the effective display region 40 and, simultaneously, arranged above the third and fourth ears 4 c and 4 d , and near an opening of the lower horizontal deflection coil 2 b at the front panel side. The first and second closed-loop coils 5 and 6 are fixed to the CRT 1 and the reinforcing band 3 by an adhesive or a self-adhesive tape so that they will not become misaligned.
The first and second closed-loop coils 5 and 6 are respectively arranged under the ears 4 a and 4 b , and above the ears 4 c and 4 d , and are further arranged in such a manner that they surround the front panel 1 a and the funnel 1 b of the CRT 1 . With this arrangement, the magnetic field leakage from the front panel 1 a or the funnel 1 b to the outside makes an interlinkage with the first closed-loop coil 5 or the second closed-loop coil 6 .
The first and second closed-loop coils 5 and 6 are also respectively arranged at the upper and lower horizontal deflection coils 2 a and 2 b at the front panel side. With this arrangement, the magnetic field given off to the front of the deflection yoke 2 also makes interlinkages with the first and a second closed-loop coils 5 and 6 .
It is a known fact that the magnetic field leakage in the vertical direction is caused due primarily to the horizontal deflection magnetic field. This means that the magnetic field leakage varies in accordance with cyclic variations in the horizontal deflection magnetic field. Meanwhile, electromotive forces that interfere with the variations in the horizontal deflection magnetic field are produced for the first and second closed-loop coils 5 and 6 . With the electromotive force, each of the first and second closed-loop coils 5 and 6 generates a magnetic field, i.e., the cancel magnetic field, in the direction opposite to the magnetic field leakage. The cancel magnetic field can reduce the magnetic field leakage by canceling the leakage occurring in a broad space from the front panel 1 a , that is nearest to the user, to the vicinity of a source of leakage.
The first and second closed-loop coils 5 and 6 are respectively grounded via earth wires 5 a and 6 a Thus, the electric field leakage is shielded and so prevented from increasing.
Effects of reducing the magnetic and electric field leakages are explained in detail. FIG. 6 is a view to help explain the relation between the cancel magnetic field generated by the first and second closed-loop coils 5 and 6 and the magnetic field escaping as leakage from the deflection yoke 2 , the relation being viewed from the left side of the CRT device shown in FIG. 4 .
As stated earlier, the first closed-loop coil 5 is arranged at the upper front of the deflection yoke 2 while the second closed-loop coil 6 is arranged at the lower front of the deflection yoke 2 in the present embodiment. As such, a magnetic field leakage 7 from the deflection yoke 2 makes interlinkages with the first and second closed-loop coils 5 and 6 . Here, in accordance with the cyclic variations in the magnetic field leakage 7 , induced currents pass through the first and second closed-loop coils 5 and 6 , so that the cancel magnetic field 8 is generated. As seen in FIG. 6, the first and second closed-loop coils 5 and 6 serve in a pair as a cancel coil for generating the cancel magnetic field 8 .
The cancellation effect on the magnetic field leakage 7 varies depending on the setting position of each closed-loop coil 5 and 6 . In the present embodiment, each setting direction of the first and second closed-loop coils 5 and 6 is appropriately determined so that the cancel magnetic field 8 with the reversed polarity is generated and effectively cancels the magnetic field leakage 7 .
It is ideal for the first and second closed-loop coils 5 and 6 to horizontally cross the effective display region 40 of the front panel 1 a and situated in a plane parallel to the axis of the CRT 1 , although this arrangement certainly blocks the user's view. With this ideal arrangement of the coils 5 and 6 , the directions of vectors of the magnetic field leakage 7 and the cancel magnetic field 8 are opposite to each other, so that the magnetic field leakage 7 can be most effectively canceled. This is because, as shown in FIG. 6, each of the closed-loop coils 5 and 6 is set so that a plane including the closed-loop coil 5 or 6 is perpendicular to a plane including the magnetic field leakage 7 , meaning that the cancel magnetic field whose vector is different from that of the leakage by 180° is generated from the closed-loop coils 5 and 6 .
The state shown in FIG. 6 is ideal for the cancellation of the magnetic field leakage. In reality, as stated, if the first and second closed-loop coils 5 and 6 horizontally crossed the effective display region 40 of the front panel 1 a , they would block the user's view. As a matter of course, the arrangement to achieve the state shown in FIG. 6 cannot be employed for the CRT device of the present invention.
In the present embodiment, the first and second closed-loop coils 5 and 6 are respectively set along the top edge 40 a and the bottom edge 40 b of the effective display region 40 , as shown in FIG. 4, so as to attain the maximum cancellation effect in practical applications. As can be readily understood, the respective setting positions of the closed-loop coils 5 and 6 present no problem for practical uses.
It is more preferable to set a closed-loop coil as a cancel coil at the upper and lower parts of the front panel 1 a as in the case of the present embodiment. However, the closed-loop coil may be set at either the upper or the lower part of the front panel 1 a . With the closed-loop coil set only at the upper part, the magnetic field escaping as leakage from the upper part of the deflection yoke 2 will be mainly canceled. Meanwhile, with the closed-loop coil set only at the lower part of the front panel 1 a , the magnetic field escaping as leakage from the lower part of the deflection yoke 2 will be mainly canceled. It should be obvious that the magnetic fields escaping from the upper and lower parts of the deflection yoke 2 can be effectively canceled when the closed-loop coil is set at both the upper and lower parts of the front panel 1 a.
The cancel coil may be composed of more than two closed-loop coils. For example, when three closed-loop coils are used as the cancel coil, two coils may be set at the upper part of the CRT 1 while a remaining closed-loop coil may be set at the lower part of the CRT 1 .
Since the first and second closed-loop coils 5 and 6 are respectively grounded via the earth wires 5 a and 6 a , the closed-loop coils 5 and 6 are at the same earth potential. As such, there has to be no difference in voltage of electromotive force between the first and second closed-loop coils 5 and 6 , so that no electric field will be generated between the closed-loop coils 5 and 6 . Therefore, not only is unnecessary electric field leakage prevented from increasing, but also the electric field leakage is reliably reduced owing to the closed-loop coils 5 and 6 serving as the shields aganist the electric field that is to escape as leakage from the deflection yoke 2 .
EXPERIMENTS
An experiment was conducted using a 40-centimeter (17-inch) computer monitor employing the CRT device of the present embodiment. In the experiment, the magnetic field leakages were measured to see the reduction effect in comparison with a conventional device.
A closed-loop coil used in the present experiment was made of a multifilament copper wire (KV0.75 type) covered with vinyl. The perimeter of the closed-loop coil was about 110 cm. Two closed-loop coils, as the first and second closed-loop coils 5 and 6 , were respectively set along the top edge 40 a and the bottom edge 40 b of the effective display region 40 , as shown in FIG. 4 . In the case of the 40-centimeter computer monitor, the front panel 1 a is 29.5 cm high and 37.2 cm wide, and the effective display region 40 is 24.3 cm high and 32.4 cm wide.
FIG. 7 is a table showing the results of magnetic field leakages measured outside the CRT device (i.e., the computer monitor) in comparison with the conventional CRT device having no closed-loop coils. The degrees in the leftmost column represent positions at which the measurements were taken (the positions are referred to as the “measurement positions” hereinafter). All of the measurement positions lie on an imaginary circle that passes through two points respectively situated at a distance of 50 cm from the front and the back of the CRT device. The degrees representing the measurement positions were measured from the point at a distance of 50 cm from the front of the CRT device (indicated as 0°) in a counterclockwise direction.
As can be seen from the table shown in FIG. 7, in comparison with the case of the conventional device that was not provided with the cancel coil, the magnetic field leakage were reduced using the present invention at the measurement positions except for the several positions located behind the CRT device. The magnetic field leakage at the 0° measurement position, at which the leakage is the greatest in general, was reduced to 20.4 nT while it was 22.9 nT in the case of the conventional device. According to the Swedish MPR II standard, the magnetic field leakage has to be equal to or less than 25 nT at this position. The magnetic field leakages of the CRT device of the present embodiment were sufficiently below this prescribed limit. As shown in the table, the magnetic field leakages of the conventional CRT device having no cancel coil were also sufficiently below the limit of 25 nT. However, the leakages can easily exceed the limit due to irregularities of produced components to be provided for a CRT device. In the present embodiment, by reducing the magnetic field leakage with a higher intention, the leakage can be reliably below the limit for any produced CRT device.
Next, another experiment was conducted to measure the electric field leakages and see the reduction effect in comparison with the conventional device. The closed-loop coils, that have been tested and shown to have the reduction effect on the magnetic field leakage in the above experiment, were grounded for the present experiment. With this construction, the closed-loop coils served as shields against the electric field that is to escape, thereby reducing the electric field leakage. In the present experiment, the measurements were taken at distances of 50 cm and 30 cm in front of the CRT device. The results are shown in the table of FIG. 9 .
As shown in the table, the electric field leakage was 1.2 V/m at a distance of 50 cm in front of the CRT device. This leakage value sufficiently below the limit of 2.5 V/m prescribed in the Swedish MPR II standard.
Second Embodiment
FIG. 10 is a perspective external view of a CRT device of the second embodiment of the present invention. The CRT device of the second embodiment is composed of a CRT 1 , a deflection yoke 2 , an electron gun 11 , a reinforcing band (or, flameproof band) 3 , a closed-loop coil 5 . The CRT 1 is made up of a front panel 1 a and a funnel 1 b . The deflection yoke 2 is made up of an upper horizontal deflection coil 2 a , a lower horizontal deflection coil 2 b , a vertical deflection coil (not illustrated), and a core (not illustrated). The reinforcing band 3 is set on the outer edge of the front panel 1 a , and first to fourth ears 4 a to 4 d are respectively formed on the four corners of the reinforcing band 3 .
The closed-loop coil 5 is set at an upper part of the CRT device. To be more specific, the closed-loop coil 5 is arranged just above a top edge 40 a of an effective display region 40 of the front panel 1 a . Simultaneously, the closed-loop coil 5 is arranged under the first and second ears 4 a and 4 b , and near an opening of the upper horizontal deflection coil 2 a at the front panel side.
A board 71 made of insulation material is mounted on the upper horizontal deflection coil 2 a via a mounting member (not illustrated). The board 71 is equipped with a differential coil 50 as a well-known coil for correcting cross-misconvergence. A part of the closed-loop coil 5 is set around the differential coil 50 , so that the closed-loop coil 5 can obtain an induced electromotive force from the differential coil 50 .
FIG. 11A is a schematic circuit diagram of the horizontal deflection coil 2 , the differential coil 50 , and the closed-loop coil 5 . As shown in this circuit diagram, coils 51 and 52 comprising the differential coil 50 are respectively connected in series with the upper and lower horizontal deflection coils 2 a and 2 b via terminals 61 and 62 . The closed-loop coil 5 is magnetically coupled to the differential coil 50 . This circuit is connected to output terminals of a horizontal deflection circuit via terminals 63 and 64 .
FIG. 11B shows a typical example of a horizontal output circuit that is provided at the final stage of the horizontal deflection circuit. A pulse voltage synchronized with a horizontal synchronizing signal is applied by a horizontal drive circuit (not shown) to a base 81 of a transistor 82 used for a switching. A positive direct current is supplied to a collector of the transistor 82 via a choking coil 87 that is used for eliminating alternating current components. The transistor 82 is brought into conduction every time the pulse voltage is applied to the base 81 . A condenser 83 is given a charge of electricity while the transistor 82 is not conducting, and discharges electricity while the transistor is conducting. Thus, a charge/discharge operation is repeated in synchronization with the pulse voltage, so that a well-known sawtooth horizontal deflection current is generated.
A damper diode 84 connected in parallel to the condenser 83 is brought into conduction when a voltage with a reversed polarity is applied exceeding a predetermined value. With the conduction by the damper diode 84 , a short is caused in an LC circuit that includes the deflection coils 2 a and 2 b and the condenser 83 , thereby preventing occurrence of unnecessary resonance.
An output terminal 89 is grounded via a linearity correction circuit that includes a linearity coil 85 and a condenser 86 that are connected in series. The linearity correction circuit is a well-known circuit for correcting a deflection current to attain the linearity for the horizontal deflection of the electron beams. The linearity coil 85 is made of a saturable coil, and the self inductance of the coil 85 varies in accordance with saturation levels at respective points of the deflection current. Taking advantage of the variations in its self inductance, the linearity coil 85 attains the linearity for the deflection current. The condenser 86 corrects the deflection current into an S-shaped manner so as in turn to correct deflection distortion occurring to the central, right, and left parts of the front panel 1 a.
In general, such a horizontal output circuit is provided for a display device, separately from a CRT device. The generated horizontal deflection current is supplied to the horizontal deflection coils 2 a and 2 b and the differential coil 50 via the terminals 63 and 64 (see FIG. 11A) that are connected to the output terminals 88 and 89 in a detachable manner.
FIG. 12 shows that a part of the closed-loop coil 5 is set around the differential coil 50 . The wire consisting the differential coil 50 is wound separately around two coil bobbins 53 to form first and second differential coils 51 and 52 . Then, a part of the closed-loop coil 5 is set around the first and second differential coils 51 and 52 to form an induction coil part 54 . A part of the closed-loop coil 5 may be set around one of the first and second differential coils 51 and 52 . The induction coil part 54 is formed so that an electromotive force is produced in a direction so as to generate a magnetic field for canceling a magnetic field escaping as leakage from the deflection coils 2 a and 2 b.
FIG. 13 shows a construction example of a magnetic coupling part of the first and second differential coils 51 and 52 and the closed-loop coil 5 . The differential coil 50 around which a part of the closed-loop coil 5 has been set is fixed to the board 71 made of insulation material, such as bakelite. The board 71 further includes the terminals 61 and 62 connected to the horizontal deflection coils 2 a and 2 b , and the terminal 64 connected to the horizontal deflection circuit.
As explained in the first embodiment with reference to FIG. 6, the cancel magnetic field 8 generated by means of the current passing through the closed-loop coil 5 cancels the magnetic field leakage 7 from the horizontal deflection coil 2 . The present embodiment is different from the first embodiment in that the cancel magnetic field 8 in the present embodiment is generated with a higher intention by passing the current, resulting from an induced voltage generated by the induction coil part 54 , through the closed-loop coil 5 . With the induced voltage, the closed-loop coil 5 generates an electric field in the direction opposite to the electric field leakage, so that the electric field leakage can be also canceled.
EXPERIMENTS
An experiment was conducted using a 40-centimeter (17-inch) computer monitor employing the CRT device of the present embodiment. As is the case with the experiment in the first embodiment, the magnetic field leakages were measured to see the reduction effect in comparison with a conventional device.
A differential coil used in the experiment was made by winding a litz wire around a cylindrical bobbin having a space inside with an inner diameter of 6 mm. The litz wire was made by tying twelve copper wires in a bundle, the thickness of each copper wire being φ0.25 mm. A screw-in magnet is set inside the space of the bobbin so that bias of inductance can be variably controlled. For the present experiment, the inductance was set at about 15 μH. A part of the closed-loop coil 5 was set as an induction coil around the differential coil so that an electromotive force was produced for canceling the magnetic and electric field leakages.
In the present experiment, the induction coil part 54 consisted of 30 turns, and an induced voltage of about 10 V was obtained as the peak voltage. By the application of the induced voltage to the rest of the closed-loop coil 5 , the cancel magnetic and electric fields are generated for canceling the magnetic and electric field leakages. FIG. 14 and FIG. 15 respectively show the measurement results of the magnetic and electric field leakages.
As shown in the table of FIG. 14, the magnetic field leakage at the 0° measurement position, at which the leakage is the greatest, was reduced to 19.3 nT while it was 22.9 nT in the case of the conventional device. Meanwhile, as shown in the table of FIG. 15, the electric field leakage was 0.8 V/m at a distance of 30 cm in front of the CRT device. This leakage value is below the limit of 1.0 V/m prescribed for this position (at a distance 30 cm in front of the CRT device) in the TCO standard and also below the limit of 2.5 V/m prescribed for this position in the MPR II standard.
In the second embodiment, the closed-loop coil 5 is magnetically coupled to the differential coil 50 . However, when the horizontal deflection circuit includes a coil through which a current varying in synchronization with the horizontal deflection current passes, the closed-loop coil 5 may be wound around the coil. For example, the horizontal deflection circuit may include a coil, such as the linearity coil 85 (see FIG. 1B) connected to the horizontal deflection coil in series or the choking coil 87 that changes the amount of passing current in accordance with the variations in the pulse voltage.
In the second embodiment, the closed-loop coil, is set only at the upper part of the CRT 1 . It should be obvious that the magnetic and electric field leakages can be effectively reduced by setting the closed-loop coil at the lower part of the CRT 1 as well. In this case, a part of the closed-loop coil set at the lower part of the CRT 1 is not necessarily set around the differential coil 50 . This is because the magnetic field leakage can be adequately canceled by means of the closed-loop coil set at the upper part of the CRT 1 .
Although tho present invention has been fully described by way of examples with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art.
Therefore, unless such changes and modifications depart from the scope of the present invention, they should be construed as being included therein. | Two closed-loop coils are respectively set at the top or the bottom of a cathode ray tube. These two closed-loop coils serves in a pair as a cancel coil. Each closed-loop coil is positioned so as to make an interlinkage with the magnetic field leakage that escapes from the deflection yoke, a part of the closed-loop coil running almost in parallel to the top or bottom edge of an effective display region of a front panel. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2004-306994, filed on Oct. 21, 2004, and is based upon Japanese Patent Application No. 2003-392279, filed on Nov. 21, 2003, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a lubricative sealing device which provides lubrication to rolling parts of ball screws, particularly between the screw groove of the ball screw shaft or the ball screw nut and the balls, and enables the ball screw to be used for a long time without replenishment of oil.
[0004] 2. Description of the Related Art
[0005] Various sealing devices of this type have been proposed so far (see, for example, Japanese Unexamined Patent Application Publication No. 10-2395 and Japanese Patent No. 3288961).
[0006] Japanese Unexamined Patent Application Publication No. 10-2395 discloses a structure in which a lubricant-impregnated rubber or synthetic resin ring is attached to the end of a ball nut with a pressing member which has projections to apply a preload to the ring in a circumferential direction.
[0007] Japanese Patent No. 3288961 discloses a sealing device that is attached to sliding members such as nuts similarly to Japanese Unexamined Patent Application Publication No. 10-2395. The lubricating oil applying member is made of polyester/wool blend felt, sintered resin, or the like, which has the merit of being able to absorb and hold more lubricant, as described in the specification.
[0008] Another structure for the sealing device is known, as described in Japanese Examined Utility Model Application Publication No. 5-43310. In this sealing device, thin seal plates having holes of shapes that correspond to the lateral cross-sectional shape of the screw groove of the ball screw shaft are circumferentially displaced and overlapped, and held in a frame-shaped ring to be attached to the end of the ball nut. This structure is effective as a sealing device.
[0009] A sealing device that can be used on any installed standard ball screw nuts by attaching to both ends of the ball screw nut is also known (see, for example, Japanese Unexamined Patent Application Publication No. 2002-147561).
[0010] In the structure disclosed in Japanese Unexamined Patent Application Publication No. 10-2395, however, pressure is constantly applied to the lubricant supplying member making contact with the balls serving as rolling elements, to keep their contact for a long time. This accordingly causes a problem of complexing lubrication mechanism.
[0011] With the structure of Japanese Patent No. 3288961, while the member that makes contact with the rolling elements, or balls, to apply oil can absorb and hold a large amount of oil, it requires a lubricating oil reservoir member (tank function) that supply oil in order to achieve constant lubricating effect. Another problem is that the lubricating oil applying and retaining member loses its resiliency in the areas contacting the balls as time passes, which leads to its plastic deformation, and as the surfaces contacting the rolling balls deteriorate, the lubricating effect may be reduced. Also, since felt materials usually have large pores, absorbed oil can readily flow out. Therefore, the structure needs to be modified such as provision of a flow rate control valve between the oil reservoir member and the oil application member, as described in the specification.
[0012] Further, the device shown in Japanese Examined Utility Model Application Publication No. 5-43310 uses a common seal material, and therefore, while it has good sealing properties, it lacks a lubricating function and is unable to supply lubricating oil stably for a long time.
[0013] Furthermore, with the device shown in Japanese Unexamined Patent Application Publication No. 2002-147561, the built-in lubricant holding member is made of a porous sintered resin material. Therefore, similar to the other conventional devices described above, the lubricating oil applying and retaining member loses its resiliency as time passes in the areas contacting the balls, which leads to its plastic deformation, and as the surfaces contacting the rolling balls deteriorate, the lubricating effect can be reduced. Accordingly, the device shown in this fourth patent document requires an oil replenishing member attached to one side, which is provided in addition to the lubricant applying member that contacts the screw groove, so that lubricant is replenished constantly from outside to the rolling parts of the screw.
SUMMARY OF THE INVENTION
[0014] The present invention has been made to solve these problems in the conventional techniques. The object is thereof to eliminate the complexity of the lubrication mechanism and provide a ball screw lubricative sealing device which is externally attachable to an installed standard ball screw nut. The ball screw lubricative sealing device is capable of retaining larger amount of lubricant and long supply of lubricating oil to the contacting screw parts, and it further includes a sealing function.
[0015] Another object of the present invention is to provide a ball screw lubricative sealing device which can be attached externally to the side face of a standard ball screw.
[0016] Yet another object of the present invention is to provide a ball screw lubricative sealing device which can be attached externally to the side face of a standard ball screw without any additional work.
[0017] A lubricative sealing device according to a first aspect of the invention includes generally cylindrical case members having attachment parts to be attached to both ends of a screw nut, respectively, a plurality of thin seal plates having a hole each and fitted inside each of the case members in such a state that they are circumferentially displaced and overlap with each other, the hole having a shape corresponding to a lateral cross-sectional shape of a screw groove of a ball screw shaft, and a plastic wiper fitted with a space from the this seal plates inside each of the case members, in which the plurality of thin seal plates are made of a lubricating oil impregnated felt-like material formed of a fiber material which is made of a three-dimensionally crosslinked plastic fiber and resilient rubber members.
[0018] In the first aspect of the invention, preferably, outer circumferential surfaces of the plurality of thin seal plates circumferentially displaced are fixed to an inner circumferential surface of each of the case members using an adhesive. Preferably, the plurality of thin seal plates are impregnated with lubricating oil after they are inserted and fixed inside each of the case members in circumferentially displaced manner.
[0019] With the first aspect of the invention, because the resilient force of the resilient rubber member exerts on the screw groove surface, the thin seal plates can provide long lubricating effect as compared to other common felt materials. Moreover, unlike the conventional devices, they can achieve effective lubrication without a mechanism such as applying pressure from an outer circumference side.
[0020] Since only the outer circumferential surface of the thin seal plates are bonded and fixed to the inner circumferential surface of each of the case members, the thin seal plates can hold sufficient amount of lubricating oil. Besides, they can move freely to follow the screw grove inside the inner circumference, so that good seal performance and effective lubricating oil application are achieved.
[0021] Further, because the thin seal plates are formed of resilient rubber members, the felt material contained therein is less likely to peel off as compared to other common felt materials. Also, the thin seal plates are capable of catching contaminants from outside in their oil-holding spaces, thereby also providing a sealing function.
[0022] Further, since the plastic wiper is located outermost of each of the case members, and the lubricant supplying thin seal plates are located with a space from the plastic wiper, contaminants from outside are removed by the plastic wiper, and small contaminants that have entered are pushed through into the next space and kept there, or caught in the lubricant supplying thin seal plates. Thus, the entry of contaminants to the inside is prevented reliably.
[0023] A lubricative sealing device according to a second aspect of the invention includes: generally cylindrical case members to be attached to both ends of a screw nut of a ball screw, respectively, using fastening bolts; a thin cap inserted and fixed inside each of the case members, a plurality of thin seal plates placed inside the thin cap and made of a lubricating oil-impregnated felt-like material formed of a fiber material which is made of a three-dimensionally crosslinked plastic fiber and resilient rubber member, and a grease reservoir space formed inside each of the case members between the plurality of thin seal plates and one end of the screw nut.
[0024] With the second aspect of the invention, because the lubricant-impregnated seal members and the grease reservoir space are placed inside each of the case members, the lubricative sealing device can be used without replenishing oil for a long time, and thus enables maintenance-free use of the ball screw.
[0025] Moreover, because of the structure in which the thin seal plates are placed inside the thin cap, the lubricative sealing device can be assembled easily.
[0026] A lubricative sealing device according to a third aspect of the invention includes either one of end caps and end covers attached to both ends of a screw nut of a ball screw, respectively, using fastening bolts each having a head with a concentric screw thread formed therein, a generally cylindrical case member to be attached to either one of the end caps and the end covers, respectively, using mounting bolts engaging them with the a concentric screw threads formed in the heads of the fastening bolts, a thin cap inserted and fixed inside each of the case members, a plurality of thin seal plates fitted inside the thin cap and made of a lubricating oil impregnated felt-like material formed of a fiber material which is made of a three-dimensionally crosslinked plastic fiber and resilient rubber members, and a grease reservoir space formed inside each of the case members between the plurality of thin seal plates and one end of the screw nut.
[0027] In either one of the second aspect and third aspect of the invention, each of the fastening bolts is preferably a bolt having a head with a hexagonal hole. Also, each of the mounting bolts is preferably a bolt having a head with a hexagonal hole. Further, outer circumferential surfaces of the plurality of thin seal plates circumferentially overlapped are preferably fixed to an inner circumferential surface of each of the case members using an adhesive. Also, the plurality of thin seal plates are preferably impregnated with lubricating oil after they are inserted and fixed inside each of the case members in the circumferentially overlapping manner.
[0028] With the third aspect of the invention, because of the lubricant-impregnated seal members and the grease reservoir space inside each of the case members, the lubricative sealing device can be used without replenishing oil for a long time, and thus enables maintenance-free use of the ball screw.
[0029] With the third aspect of the invention, the lubricative sealing device can be attached to a ball screw nut only with a devisal to the mounting screw and without any additional work to the ball screw structure, whereby a cost reduction can be achieved.
[0030] The double screw structure of each of the fastening bolts that attaches the component such as the end cap or the end cover having a concentric screw hole, provides a side advantage that the case member of the lubricative sealing device is firmly attached by the mounting screw fitted in the concentric screw hole of the fastening bolt.
[0031] Also, with the use of the fastening bolt having the above-described double screw structure that attaches a component of a standard ball screw such as an end cover, it is made unnecessary to do additional work to the ball screw or disassemble the ball screw at the time of installing the lubricative sealing device. Therefore, ball screw accuracy and assembling accuracy of the ball circulation parts will not be lowered.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The nature, principle, and utility of the invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings in which like parts are designated by identical reference numbers, in which:
[0033] FIG. 1 is a cross-sectional view of a ball screw lubricative sealing device 1 according to the first embodiment of the present invention, which is assembled to one end of a ball screw nut;
[0034] FIG. 2 is an exploded perspective view of the ball screw lubricative sealing device 1 according to the first embodiment of the present invention;
[0035] FIG. 3 is a cross-sectional view showing the relationship between each of thin seal plates 11 A, 11 B, and 11 C and a ball screw shaft 3 in the ball screw lubricative sealing device 1 according to the first embodiment of the present invention;
[0036] FIG. 4 is a partially cut-away side view of a ball screw lubricative sealing device according to the second embodiment of the present invention;
[0037] FIG. 5 is a front view of the case member of FIG. 4 ;
[0038] FIG. 6 is a perspective view showing how the lubricative sealing part of FIG. 4 is assembled;
[0039] FIG. 7 is a cross-sectional view illustrating the relationship between each of thin seal plates 27 A, 27 B, and 27 C and a ball screw shaft 22 of FIG. 4 ;
[0040] FIG. 8 is a partially cut-away side view of a ball screw lubricative sealing device according to the third embodiment of the present invention;
[0041] FIG. 9 is an exploded cross-sectional view illustrating how the mounting screw of FIG. 8 is connected; and
[0042] FIG. 10 is a cross section taken along the line A-A in FIG. 9 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] Various embodiments of the present invention shown in the drawings will be hereinafter described.
First Embodiment
[0044] FIG. 1 is a cross-sectional view of a ball screw lubricative sealing device 1 according to a first embodiment of the present invention which is assembled to one end of a ball screw nut, FIG. 2 is an exploded perspective view of the ball screw lubricative sealing device 1 according to the first embodiment of the present invention, and FIG. 3 is a cross-sectional view showing the relationship between each of thin seal plates 11 A, 11 B, and 11 C and a ball screw shaft 3 in the ball screw lubricative sealing device 1 according to the first embodiment of the present invention.
[0045] The ball screw lubricative sealing device 1 according to this embodiment includes: generally cylindrical case members 9 having attachment parts 9 d to be connected to both ends of a screw nut 7 , respectively, which are threadably engaged with a ball screw shaft 3 having a helical groove 5 , with rolling elements such as steel balls (not shown) interposed therebetween; three thin seal plates 11 A, 11 B, and 11 C having holes 11 a , 11 b , and 11 c that correspond to the lateral cross-sectional shape of the helical groove 5 of the screw shaft 3 and set in a groove 9 a of each of the case members 9 in such a state that they are circumferentially displaced and overlapping with each other; and a plastic wiper 13 set inside each of the case members 9 that accommodates the three thin seal plates 11 A, 11 B, and 11 C with a space 9 e from the three thin seal plates 11 A, 11 B, and 11 C. The outer circumferential surfaces of the three overlapped thin seal plates 11 A, 11 B, and 11 C are fixed to the inner circumferential surface of each of the case members 9 using an adhesive. The three thin seal plates 11 A, 11 B, and 11 C are made of a felt-like material impregnated with a lubricating oil, the felt-like material being formed of a fiber material which is made of a three-dimensionally crosslinked plastic fiber and resilient rubber members.
[0046] Each of the case members 9 is generally cylindrical and has the same size as the outer shape of either end of the screw nut 7 . Each of the case members 9 has the attachment part 9 d at one end, which is threadably engaged with a cavity 11 a provided at either end of the screw nut 7 . Inside each of the case members 9 there are the groove 9 a for setting the three thin seal plates 11 A, 11 B, and 11 C, an annular projection 9 c for forming the space 9 e , and a groove 9 b for setting the plastic wiper 13 by screwing or bonding.
[0047] The fiber material made of three-dimensionally crosslinked plastic fiber and the resilient rubber members, which forms the three thin seal plates 11 A, 11 B, and 11 C, is obtained by adhering molten rubber on the surfaces of thin polyester plastic fibers, in which the integrated fiber material has a multiplicity of spaces between the fibers. These spaces are filled with a lubricant such as grease to form a lubricant supply unit. Polyester resin is effectively used as the base resin of the plastic fiber, but the material is not limited to this.
[0048] Next, the mechanism of the thus structured embodiment of the ball screw lubricative sealing device 1 will be described.
[0049] Firstly, referring to FIG. 1 and FIG. 2 , the three lubricant-impregnated thin seal plates 11 A, 11 B, and 11 C are circumferentially displaced and overlapped in the groove 9 a of the case member 9 . After they are fixedly bonded in the groove 9 a of the case member 9 , the plastic wiper 13 is set in the outer groove 9 b of the case member 9 .
[0050] Next, the attachment part 9 d of the case member 9 is threadably engaged with the cavity 11 a at either end of the screw nut 7 .
[0051] Next, the ball screw shaft 3 is inserted into the hole 13 a of the plastic wiper 13 and the holes 11 a , 11 b , and 11 c of the three thin seal plates 11 A, 11 B, and 11 C.
[0052] Thereby, the holes 11 a , 11 b , and 11 c of the three thin seal plates 11 A, 11 B, and 11 C make contact with the screw groove 5 of the ball screw shaft 3 , as shown in FIG. 3 .
[0053] The holes 11 a , 11 b , and 11 c of the three thin seal plates 11 A, 11 B, and 11 C make pressure contact with the surface of the screw groove 5 of the ball screw shaft 3 because of the resiliency of the resilient rubber member, whereby the thin seal plates provide lubricating effect for a longer time as compared to known felt materials.
[0054] Further, the plastic wiper 13 located on the outer side of the case member 9 removes most of the contaminants from outside. Small contaminants that have passed through the plastic wiper 13 are trapped in the space 9 e . Contaminants that proceed further inside are caught and kept in the interspaces between the fibers of the three thin seal plates 11 A, 11 B, and 11 C. Entrance of contaminants from outside is thus prevented reliably.
[0055] As described above, with this embodiment of the ball screw lubricative sealing device 1 , effective lubrication is achieved without any mechanism for applying pressure from an outer circumferential side as with the conventional device.
[0056] While the three thin seal plates 11 A, 11 B, and 11 C used in the above-described embodiment are preliminarily impregnated with a lubricating oil, this is not a requirement of the present invention and the thin seal plates 11 A, 11 B, and 11 C may be impregnated with a lubricating oil after they are fixedly set inside the case member 9 .
[0057] Also, while three thin seal plates 11 A, 11 B, and 11 C are used in the above-described embodiment, this is not a requirement of the present invention and the number of thin seal plates may be suitably selected according to needs.
[0058] Further, while the ball screw shaft 3 has a single-thread screw groove 5 in the above-described embodiment, this is not a requirement of the present invention and the screw shaft may have any number of threads.
[0059] Furthermore, while the case member 9 is attached to the screw nut 7 by threadably engaging the attachment part 9 d with the cavity 11 a at either end of the screw nut 7 in the above-described embodiment, this is not a requirement of the present invention and the case member may be attached by any other means.
Second Embodiment
[0060] FIG. 4 to FIG. 7 show a ball screw lubricative sealing device 20 according to a second embodiment of the present invention.
[0061] This embodiment of the ball screw lubricative sealing device 20 includes: generally cylindrical case members 24 that is connected to both ends 21 a of a screw nut 21 using fastening bolts (having a head with a hexagonal hole) 25 and screw holes 21 b formed in both ends 21 a of the screw nut 21 , which are threadably engaged with a ball screw shaft 22 having a helical groove 23 , with rolling elements such as steel balls (not shown) interposed therebetween; a thin cap 26 having a hole 26 a which is large enough to allow the ball screw shaft 22 to extend through and being fixedly set in a seal accommodating hole 24 a of each of the case members 24 ; three thin seal plates 27 A, 27 B, and 27 C having holes 27 a , 27 b , and 27 c that match the lateral cross-sectional shape of the helical groove 23 of the ball screw shaft 22 and being overlapped in a circumferentially displaced manner and set in the thin cap 26 as shown in FIG. 6 and FIG. 7 ; and a grease reservoir space 28 formed inside each of the case members 24 between the three thin seal plates 27 A, 27 B, and 27 C and the end 21 a of the screw nut 21 .
[0062] The outer circumferential surfaces of the three overlapped thin seal plates 27 A, 27 B, and 27 C and the inner circumferential surface of the thin cap 26 have substantially the same area, and they are fixed to each other using an adhesive. The fiber material made of three-dimensionally crosslinked plastic fiber and resilient rubber members, which forms the three thin seal plates 27 A, 27 B, and 27 C, is obtained by adhering molten rubber on the surfaces of thin polyester plastic fibers, and the integrated fiber material has a multiplicity of spaces between the fibers. These spaces are filled with a lubricant such as a grease to form a lubricant supply unit. Polyester resin is effectively used as the base resin of the plastic fiber, but the material is not limited to this.
[0063] Each of the case members 24 is generally cylindrical and has the same size as the outer shape of the end 21 a of the screw nut 21 . On the inner side next to the seal accommodating hole 24 a is formed a hole 24 b with a smaller diameter, and in the bottom of this hole, a hole 24 c is formed which is large enough to allow the screw shaft 22 to extend through. Reference numeral 29 in the drawing shows a screw that plugs an opening 24 f for supplying a lubricant such as grease into the grease reservoir space 28 .
[0064] As shown in FIG. 5 , each of the case members 24 further includes deep spot face holes 24 d at three equally distanced locations from the side of the hole 24 a to as far as near the other end face 24 g , and concentric holes 24 e that are bored from the bottom of these spot face holes, to form the mounting holes for the fastening bolts 25 .
[0065] Next, the mechanism of the thus structured ball screw lubricative sealing device 20 according to the embodiment will be described.
[0066] Referring to FIG. 4 and FIG. 6 , first, the three lubricant-impregnated thin seal plates 27 A, 27 B, and 27 C are circumferentially displaced and overlapped in the thin cap 26 and fixed in the thin cap 26 using an adhesive, after which the thin cap is set in the seal accommodating hole 24 a of each of the case members 24 and fixed using an adhesive.
[0067] Next, three fastening bolts 25 are set in the holes 24 d and 24 e at three locations of each of the case members 24 , to secure the case members 24 to both ends 21 a of the screw nut 21 .
[0068] Next, the ball screw shaft 22 is inserted into the hole 26 a of the thin cap 26 and the holes 27 a , 27 b , and 27 c of the three thin seal plates 27 A, 27 B, and 27 C.
[0069] Thereby, the hole 26 a of the thin cap 26 and the holes 27 a , 27 b , and 27 c of the three thin seal plates 27 A, 27 B, and 27 C make contact with the screw groove 23 of the ball screw shaft 22 , as shown in FIG. 7 .
[0070] The holes 27 a , 27 b , and 27 c of the three thin seal plates 27 A, 27 B, and 27 C make pressure contact with the surface of the screw groove 23 of the ball screw shaft 22 because of the resiliency of the resilient rubber member, whereby the thin seal plates provide lubricating effect for a longer time as compared to known felt materials.
[0071] Further, the thin cap 26 located inside the seal accommodating hole 24 a of each of the case members 24 removes most of the contaminants from outside. Small contaminants that have passed through the thin cap 26 and proceed further inside are caught and kept in the interspaces between the fibers of the three thin seal plates 27 A, 27 B, and 27 C. Entrance of contaminants from outside is thus prevented reliably.
[0072] As described above, with the ball screw lubricative sealing device 20 according to this embodiment, effective lubrication is achieved without any mechanism for applying pressure from an outer circumferential side as with the conventional device.
[0073] Moreover, the ball screw lubricative sealing device 20 according to this embodiment can be attached to the screw nut 21 by providing the screw holes 21 b at the ends 21 a of the screw nut 21 , and an end cover or the like need not be attached to the end faces of the screw nut 21 .
[0074] While the three thin seal plates 27 A, 27 B, and 27 C used in the above-described embodiment are preliminarily impregnated with a lubricating oil, this is not a requirement of the present invention and the thin seal plates 27 A, 27 B, and 27 C may be impregnated with a lubricating oil after they are fixedly set inside the thin cap 26 .
[0075] Also, while three thin seal plates 27 A, 27 B, and 27 C are used in the above-described embodiment, this is not a requirement of the present invention and the number of thin seal plates may be suitably selected according to needs.
[0076] Further, while the ball screw shaft 22 has a single-thread screw groove 23 in the above-described embodiment, this is not a requirement of the present invention and the screw shaft may have any number of threads.
Third Embodiment
[0077] FIG. 8 to FIG. 10 illustrate a ball screw lubricative sealing device 20 A according to a third embodiment of the present invention.
[0078] The ball screw lubricative sealing device 20 A according to this third embodiment is different from the ball screw lubricative sealing device 20 according to the second embodiment in that end caps 39 is provided to both ends 21 a of the screw nut 21 and the case members 24 are attached to these end caps 39 .
[0079] Therefore, the same elements as those of the ball screw lubricative sealing device 20 according to the second embodiment are given the same reference numerals and will not be described again.
[0080] Each of the end caps 39 is provided with screw holes 39 a that are coaxial with the screw holes 21 b of the screw nut 21 . Fastening bolts 40 are set in the screw holes 39 a . Each of the fastening bolts 40 has a head with a hexagonal hole as shown in FIG. 9 and FIG. 10 and includes a coaxial screw hole 40 b bored in the bottom of the hexagonal hole 40 a . Not to mention, this screw hole 40 b has a smaller diameter than the inner circle diameter of the hexagonal hole 40 a . While the screw hole has a bottom as it is bored only partway in the illustrated example, the screw hole may extend through to the bottom, or, the screw hole may be bored partway and connected to a clear hole that extends through to the bottom.
[0081] Each of the case members 24 is secured to the end cap 39 using mounting screws (bolts with a head having a hexagonal hole) 41 having a screw part that engages with the screw holes 40 b.
[0082] Next, the mechanism of the thus structured ball screw lubricative sealing device 20 A according to the embodiment will be described.
[0083] First, the end caps 39 are attached to both ends 21 a of the screw nut 21 by the fastening bolts 40 set in the screw holes 39 a.
[0084] Next, as with the second embodiment, the lubricant-impregnated three thin seal plates 27 A, 27 B, and 27 C are circumferentially displaced and overlapped in the thin cap 26 , and fixed in the thin cap 26 using an adhesive, after which the thin cap is set into the seal accommodating hole 24 a of each of the case members 24 and fixedly attached using an adhesive.
[0085] Next, three mounting screws 41 are set in the screw holes 40 b of the fastening bolts 40 through the holes 24 d and 24 e formed at three locations of each of the case members 24 , to secure the case members 24 to both ends 21 a of the screw nut 21 .
[0086] Next, the ball screw shaft 22 is inserted into the hole 26 a of the thin cap 26 and the holes 27 a , 27 b , and 27 c of the three thin seal plates 27 A, 27 B, and 27 C.
[0087] Thereby, the hole 26 a of the thin cap 26 and the holes 27 a , 27 b , and 27 c of the three thin seal plates 27 A, 27 B, and 27 C make contact with the screw groove 23 of the ball screw shaft 22 , as shown in FIG. 7 .
[0088] The holes 27 a , 27 b , and 27 c of the three thin seal plates 27 A, 27 B, and 27 C make pressure contact with the surface of the screw groove 23 of the ball screw shaft 22 because of the resiliency of the resilient rubber member, whereby the thin seal plates provide lubricating effect for a longer time as compared to known felt materials.
[0089] Further, the thin cap 26 located inside the seal accommodating hole 24 a of each of the case members 24 removes most of the contaminants from outside. Small contaminants that have passed through the thin cap 26 and proceed further inside are caught and kept in the interspaces between the fibers of the three thin seal plates 27 A, 27 B, and 27 C. Entrance of contaminants from outside is thus prevented reliably.
[0090] As described above, with the ball screw lubricative sealing device 20 A according to this embodiment, the device can be attached to the ball screw after the ball screw has been assembled. Therefore, the ball screw and the lubricative sealing device can be assembled separately, which improves work efficiency and enables simple attachment of the lubricative sealing device even after making adjustments to the assembled ball screw. This prevents accuracy deterioration of the ball screw, prevents deterioration of ball circulation performance that is caused by disassembling or the like, and eliminates the need of re-adjustments after the disassembling.
[0091] While this embodiment uses the end caps 39 , this is not a requirement of the present invention, and an end cover may also be used.
[0092] Further, each of the mounting screws 41 need not necessarily have a head with a hexagonal hole, and hexagonal bolts and any other screws may be used.
[0093] Furthermore, a plastic wiper, a lip seal, or the like may be set in the seal accommodating hole 24 a of the case member 24 that is located outside and slightly spaced from the plurality of thin seal plates 27 A, 27 B, and 27 C fitted in the thin cap 26 that is fixedly set inside each of the case members 24 , to prevent entrance of contaminants from outside or grease leakage from inside.
[0094] The invention is not limited to the above embodiments and various modifications may be made without departing from the spirit and scope of the invention. Any improvement may be made in part or all of the components. | The invention provides a ball screw lubricative sealing device having a simplified lubrication mechanism. It is attachable to an installed standard ball screw nut, capable of retaining larger amount of lubricant and long supply of lubricant to the contacting screw parts, and further includes a sealing function. It includes: generally cylindrical case members having attachment part to be attached to both ends of a screw nut, respectively; plural thin seal plates made of lubricating oil impregnated felt-like fiber material which is a three-dimensionally crosslinked plastic fiber and resilient rubber members, and having a hole each and fitted inside said case member in such a state that they circumferentially overlap with each other, the hole having a shape corresponding to a lateral cross-sectional shape of a screw groove of ball screw shaft; and a plastic wiper fitted with a space from the thin seal plates inside each of the case member. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Phase application submitted under 35 U.S.C. §371 of Patent Cooperation Treaty application serial no. PCT/DE2011/001545, filed Aug. 3, 2011, and entitled CLEANING OF A TURBO-MACHINE STAGE, which application claims priority to German patent application serial no. 10 2010 033 157.0, filed Aug. 3, 2010, entitled REINIGUNG EINER TURBOMASCHINENSTUFE and German patent application serial no. 10 2010 045 869.4, filed Sep. 17, 2010, entitled REINIGUNG EINER TURBOMASCHINENSTUFE.
Patent Cooperation Treaty application serial no. PCT/DE2011/001545, published as WO 2012/025090, German patent application serial no. 10 2010 033 157.0, and German patent application serial no. 10 2010 045 869.4, are incorporated herein by reference.
TECHNICAL FIELD
The invention relates to a method for cleaning a machine stage of a gas turbine as well as to the use of a cleaning nozzle in such a method.
BACKGROUND
Impurities, for example, sand, dust, volcanic ash, sea or fertilizer salt, chemicals, oil, lubricants and the like are deposited on the blades of the individual compressor and turbine stages of airplane engine gas turbines, and adhere there, becoming encrusted in particular, so that the airplane engine is negatively affected. This is also referred to as “fouling.”
From the category-defining WO 2005/120953 A1, it is known to spray a liquid cleaning agent, particularly water with or without additives, into the engine from the front, in order to remove these foreign materials mechanically and chemically.
The disadvantage here is, on one hand, that the soiled cleaning agent has to be discarded after use by means of a separate collection device, and, on the other hand, the engine stages, particularly turbine stages, located further downstream cannot be acted on optimally.
The present invention is based on the problem of improving the cleaning of a turbo-machine stage and reducing at least one of the above-mentioned disadvantages. The term turbo-machine stage denotes both a compressor stage and also a turbine stage.
SUMMARY AND DESCRIPTION
The aforementioned problem is addressed by a method having the characteristics described and claimed herein. A cleaning nozzle designed for this purpose is described in addition to the use of said nozzle. Advantageous variants of these methods and apparatus are also described and claimed.
According to a first aspect of the present invention, a blade of a machine stage to be cleaned is acted upon, sprayed in particular, by solid particles which sublime at the blade temperature. The blade temperature here denotes the temperature, in particular the minimum temperature, of the blade during the cleaning, and subliming denotes, as is customary in the field, the at least substantially direct transition from the solid phase to the gas phase.
It is advantageous that due to sublimation less or no liquid wastes have to be discarded. On the other hand, the sudden sublimation as well as the thermal shock can be used advantageously in addition to the kinetic energy in order to clean the blades.
In a preferred embodiment, the acting solid particles comprise dry ice or are dry ice particles. Dry ice, i.e., frozen carbon dioxide (CO 2(s) ) undergoes a transition at normal pressure of approximately 1 bar and at approximately −78° C. from the solid phase to the gas phase (CO 2(g) ). After the cleaning, it escapes as a harmless component of the air into the environment. Considering this preferred embodiment, it becomes clear that the sublimation temperature, particularly the triple point, of the solid particles can also be lower than the blade temperature, as long as the solid particles (also still) sublime at the blade temperature.
The solid particles can be applied to the blades in a gas jet, for example, as a dry ice jet, or as a finely distributed solid snow, for example, a CO 2 snow. The particles of a dry ice jet, which are obtained from “solid CO2,” typically have a higher density and as a result they produce a stronger mechanical attack against the soiling. On the other hand, CO 2 snow (produced from compressed CO 2 gas) has a gentler action. Furthermore, additional media (hard particles) can be introduced into the dry ice, in order to increase the cleaning effect.
According to a second aspect of the present invention, which can preferably be combined with the above explained first aspect, a cleaning nozzle is inserted between a machine stage to be cleaned and an adjacent machine stage of a multistage turbo-machine. The nozzle is used to cause a cleaning agent, in particular the above explained solid particles, to act on the blades of the stage to be cleaned. For this purpose, in a preferred embodiment, inspection openings can be used which, in airplane engines, for example, are provided anyway for the boroscope inspection of the stage(s). Similarly, it is also possible to provide special cleaning openings for the introduction of the cleaning nozzle, in particular already at the time of the manufacture of the turbo-machine, or only at a later time. Other openings that are not used primarily for the inspection can also be used for the cleaning, such as, for example, openings for fuel nozzles or spark plugs. If, in a preferred embodiment, the cleaning nozzle is introduced into a flow channel in which the blades of the stage to be cleaned are arranged as rotor blades or stator blades, it is particularly advantageous to close the opening(s) through which the cleaning nozzle is introduced for the cleaning again in a fluid-tight manner after the cleaning, for example, by screwing in a plug which, in a preferred variant, is attached in a loss-proof manner on the turbo-machine and removed temporarily for the cleaning.
Due to the introduction of at least one cleaning nozzle in between at least one turbo-machine stage, the latter can be cleaned in a more targeted and direct manner than by the injection of water from a turbo-machine intake. It is also possible to introduce several nozzles into different openings, so that several stages are cleaned simultaneously and/or a single stage is cleaned more rapidly. In the process it is possible to arrange several openings on or in the vicinity of a stage over the periphery.
The first and/or second aspects are used to particularly great advantage in compressor or turbine stages, particularly high-pressure compressor or turbine stages, of gas turbines, particularly of airplane engines, in order to clean the rotor and/or stator blades of this (these) stage(s).
According to a preferred embodiment of the present invention, the turbo-machine stage is rotated manually and/or motor-driven in situ during the cleaning, preferably at a speed of rotation of 1-10 rotations per minute (rpm), particularly 5 rpm, and particularly preferably 3 rpm. For the manual rotation, it is preferred to attach a suitable lever detachably to the turbo-machine or to the rotor comprising the stage to be cleaned. A motor-driven rotation can occur similarly by a drive system of the turbo-machine, for example, a starter motor, or by a separate drive system attached detachably to the turbo-machine or to the rotor comprising the stage to be cleaned. In situ refers particularly to the installed and/or at least substantially assembled turbo-machine, for example, as the airplane engine that is attached to the airplane or also industrial gas turbines (IGT), and/or at least substantially non-disassembled, airplane engines or IGTs. However, disassembled modules can also be cleaned.
In a preferred embodiment, the cleaning nozzle is radially displaced manually and/or motor-driven, in order to clean a blade preferably over its entire radial length or a (particularly) soiled radial area, for example, at the blade head or foot. In order to simplify the manual displacement, the cleaning nozzle can have radially spaced markings or gratings. The motor-driven displacement, for example, by means of a linear motor or a rotation motor with corresponding gear mechanism, can—like manual displacement—occur continuously or in discrete sections, particularly in a rasterized manner.
According to an embodiment, the radial displacement occurs during a rotation of the turbo-machine stage. In the process, the cleaning nozzle is secured in a radial position, and the turbo-machine stage is rotated at least once in such a manner that all the blades are moved past the cleaning nozzle. If only one cleaning nozzle is provided for cleaning the stage, the turbo-machine stage is thus rotated at least once completely, i.e., by 360°, whereas if two or more cleaning nozzles are provided, the turbo-machine stage is rotated accordingly by at least 360° divided by the number of the cleaning nozzles. Subsequently, the cleaning nozzle is displaced in a radial direction, and the turbo-machine stage is again rotated at least once in such a manner that all the blades are moved past the cleaning nozzle.
Similarly, the radial displacement can also occur after a rotation of the turbo-machine stage. In the process, a blade is first cleaned, in that the cleaning nozzle, when the stage is not rotating, is radially displaced, and in the process sweeps over the area to be cleaned, preferably at least substantially the entire blade. Subsequently, the turbo-machine stage is further rotated, until the cleaning nozzle sweeps over another, particularly the adjacent, blade, and repeats the radial displacement, preferably in the opposite direction, in order to minimize the travelling distance of the cleaning nozzle which thus preferably moves over one blade radially from the inside toward the outside, and over the next blades radially from the outside toward the inside. Here too, it is of course possible to provide several cleaning nozzles, wherein the turbo-machine stage is then preferably further rotated, until all the cleaning nozzles sweep over another, particularly an adjacent blade. Thus, for example, if two cleaning nozzles are associated in the peripheral direction with two adjacent blades, the turbo-machine stage is further rotated by two blade separations.
According to a preferred embodiment of the present invention, a jet outlet direction of the cleaning nozzle or a jet outlet direction of the action delivery, comprises particularly an at least substantially constant, radial and/or peripheral component. It is particularly advantageous for the jet outlet direction to form an angle with an axial direction of the turbo-machine of 10-20°. This angle can be set variably. In the peripheral direction, the jet outlet direction is preferably at least substantially oriented like a flow of the work fluid during the operation of the turbo-machine, so that, for example, the rotor blades of a compressor or turbine stage are acted upon preferably substantially with the flow exposure angle of the design. This is gentle particularly for the turbo-machine stage. Moreover, the cleaning nozzle can comprise several nozzle openings, wherein at least one nozzle opening can be opened or closed by a gate valve.
In particular, if, according to the first aspect of the present invention, a blade of a turbo-machine stage to be cleaned is acted upon by solid particles which sublime at the blade temperature, it is preferred for the blade temperature during the cleaning to be higher, particularly by at least 10° C., than the environmental temperature. In a preferred embodiment, this can be achieved by residual heat of the turbo-machine, particularly of an airplane engine and/or by an additional heating device which, for example, heats the turbo-machine stage directly, for example, by induction, or by heat conduction, or indirectly, particularly by convection or by heat transmission or transfer. In addition or alternatively, the blade temperature preferably also has an upper limit, and in a preferred embodiment, it is at most 170° C., preferably at most 150° C.
A solid particle mass flow of at least 0.1 kg/min, preferably at least 0.6 kg/min and/or at most 1.0 kg/min, preferably at most 0.7 kg/min in itself has been found to be particularly advantageous. Here, it is preferred for the cleaning jet, particularly the compressed air of a dry ice jet, to have a pressure of 4-10 bar.
In order to shorten the cleaning time, it can be advantageous, as already explained, to introduce several cleaning nozzles and/or act upon several blades and/or stages at the same time. Two cleaning nozzles here can act similarly on different blades of the same stage or blades of different stages. This depends particularly on the cleaning or inspection openings through which the cleaning nozzles are introduced. It can be advantageous for the inspection or cleaning openings or the cleaning nozzles introduced into the latter to be mutually offset in the peripheral direction in different stages, so that a cleaning agent that flows past a blade additionally hits axially adjacent blades which at that time are not acted upon. Similarly, it can be advantageous if the inspection or cleaning openings or the cleaning nozzles introduced into the latter are not mutually offset in the peripheral direction in different stages, so that the access is simplified over the axial length of the turbo-machine. In the case of several cleaning nozzles for one stage, it is possible to provide that each blade is acted upon only by the same nozzle, so that all the blades are already swept over in the case of a rotation by 360° divided by the number of the cleaning nozzles. Similarly, it is possible to provide that each blade is acted upon by different nozzles, so that the cleaning action is increased. For example, if two cleaning nozzles are arranged with mutual offset by the blade separation in the peripheral direction, the stage can be further rotated, on the one hand, by twice the blade separation, so that each n th blade is acted upon by the first, and each (n+1) th blade by the second cleaning nozzle. Similarly, the stage can be further rotated by the blade separation, so that each blade is acted upon by the first and then by the second cleaning nozzle.
A cleaning nozzle provided for the cleaning according to the invention of a turbo-machine stage, according to a preferred embodiment of the present invention, comprises at least partially a stick-slip coating which comprises particularly MoSi2 and/or PTFE, in order to prevent freezing of the operation. This coating can be applied particularly as a lacquer or as a shrunk-on hose.
In addition or alternatively, at least one radially front portion of the cleaning nozzle can be produced from a material, particularly aluminum or an aluminum alloy, which is softer than the turbo-machine stage, in order to minimize in this manner damage to the stage during an unwanted contact with the cleaning nozzle. In particular, a material in the sense of the present invention is softer than another material, if its Brinell, Vickers or Rockwell hardness or the hardness determined according to another method is at least 10% lower than that of the other material.
In addition or alternatively, the cleaning nozzle can comprise a contact protection. The latter consists particularly of a softer material than the turbo-machine stage and it can be arranged particularly in an annular manner on a radially front partial area of the cleaning nozzle.
According to a preferred embodiment of the present invention, the cleaning nozzle comprises a guide pipe in which an inner pipe with a nozzle opening is shiftably arranged. Said cleaning nozzle makes it possible to introduce the guide pipe into the turbo-machine and secure it there, wherein the radial displacement of the cleaning nozzle takes place by a displacement of the inner pipe in the guide pipe. As explained above, the displacement can occur manually or be motor-driven, and continuously or discretely. For this purpose, for example, the inner pipe can have markings or gratings, or a drive system can displace the inner pipe in the guide pipe.
According to a preferred embodiment of the present invention, the cleaning nozzle comprises particularly a screwable guide means for the detachable securing to the turbo-machine. Such a guide means can comprise, for example, a screw-in sleeve or a screw thread which is screwed in particular into an inspection or cleaning opening in the turbo-machine, and which fixes the above explained guide pipe axially and rotationally thereto.
According to a preferred embodiment of the present invention, the cleaning nozzle has one or more handles for thermal insulation, to protect the user from the cold of the dry ice.
DESCRIPTION OF FIGURES
Additional characteristics and advantages result from the dependent claims and the embodiment example. Moreover, in a partially diagrammatic representation:
FIG. 1 shows a partial section of an airplane engine with a cleaning nozzle for cleaning which is inserted between two stages, according to an embodiment of the present invention;
FIG. 2 shows the portion of the airplane engine of FIG. 1 in a developed view in the peripheral direction; and
FIG. 3 shows the detail marked “A” in FIG. 1 in an enlarged representation.
DETAILED DESCRIPTION
FIG. 1 shows a portion of a high-pressure compressor or a high-pressure turbine of an airplane engine in an axial cross section with several stages each comprising rotor blades 100 and stator blades 200 .
Between two stator blades of a stage, as one can see particularly in FIG. 2 , an inspection opening 220 is provided in the flow channel and engine outer wall 210 , which can be closed in a detachable manner by a plug (not shown, because removed in FIGS. 1, 2 ).
Through this opening 220 , a cleaning nozzle 1 is introduced. It comprises a guide pipe 11 made of a steel or aluminum alloy with two thermally insulating handles 12 A, 12 B and a detachable clamp 13 , as well as an inner pipe 10 which can be displaced in the guide pipe 11 , and on the front face of which, facing away from the handles, nozzle opening 16 is arranged, which is represented in detail in FIG. 3 . This clamp 13 can be designed as a rubber fixation and/or as a magnet. Furthermore, the inner pipe 10 can be made of Nitinol and/or it can be flexible. On the radially front marginal area of the inner pipe 11 produced from an aluminum alloy an annular contact protection 15 made of soft aluminum is arranged.
To the cleaning nozzle 1 , a hose 14 is connected through which a dry ice jet, i.e., compressed air, entrains and supplies the dry ice particles, and is sprayed through the nozzle opening 16 of the cleaning nozzle 1 onto the rotor blades 100 . Instead of such a dry ice jet, a CO 2 snow jet with finer, crystalline dry ice particles can also be used. Both can be removed from a reservoir or produced, for example, by a scrambler as needed.
For the cleaning, the cleaning nozzle 1 is introduced through the inspection opening 220 , and the guide pipe 11 is secured manually or by the clamp 13 to the turbo-machine. The inner pipe 10 can be displaced axially, but it is guided in a rotationally fixed manner in the guide pipe 11 , so that the angular position of the guide pipe 11 on the turbo-machine also defines the angular position of the inner pipe 10 relative to the rotor blade 100 and stator blade 200 .
The inner pipe is successively led into different radial (vertical in FIG. 1 ) indexed positions and maintained there. Then, the rotor 110 of the engine is rotated at a speed of rotation of approximately 1-3 rpm in each case by at least 360°, while dry ice through the nozzle opening 16 of the cleaning nozzle 1 acts on the rotor blades 100 that rotate past, as indicated in FIGS. 1, 2 by the flow arrows of the dry ice or CO 2 snow jet. If all the blades 100 at this radial height have been cleaned, then the inner pipe 10 is guided into the next radial indexed position, which can be provided, for example, by markings, and maintained there, and subsequently the rotor 110 is again rotated by at least 360°. This process is repeated until all the blades of the stage have been cleaned in the desired radial area, preferably over their entire channel height.
The rotor 110 can also be rotated repeatedly by a radial displacement of the inner pipe in order to act repeatedly on the blades in the same radial range, and thus clean them more thoroughly. Similarly, it is also possible to clean a blade by radial displacement of the inner pipe 10 , before the rotor 110 has further rotated by one blade separation, and in this manner the next blade in the peripheral direction is cleaned.
One can see in FIGS. 1, 3 that the jet outlet direction, in which the dry ice CO 2 snow jet exits from the nozzle opening 16 and acts on the rotor blades 100 , is slanted against the axial direction (horizontal in FIGS. 1-3 ) by an angle α which is approximately 15°. In the peripheral direction as well, the jet outlet direction, as can be seen in FIG. 2 , is inclined against the axial direction, so that the dry ice and/or CO 2 snow jet and/or liquid CO 2 hits the rotor blades at approximately the orientation that the work fluid also has during the operation. In turn, solid and liquid CO 2 can then be introduced. These components in the radial and peripheral direction are preferably constant, and they can be set by an appropriate securing of the inner pipe 10 in the guide pipe 11 , particularly a rotationally fixed, axially shiftable, mounting, so that an appropriate securing of the guide pipe 11 on the engine wall 210 , for example, by markings or an adapter (not shown). On the inner pipe 10 it is preferable to attach a sensor to determine the separation and/or soiling type and/or soiling degree. Accordingly, the radiation parameters, such as, pressure, temperature, particle speed, nozzle number, nozzle diameter and/or rotation angle of the cleaning nozzle, can be set or regulated. To further improve the cleaning effect, a heating device (laser, IR lamp) can be attached on the inner pipe 10 , in order to be able to heat the object to be cleaned before the CO 2 jets.
To increase or improve the cleaning quality, a gas flow can be led additionally through the engine. To further improve the cleaning quality, it is possible, alternatively or in combination, to subject the engine to a preliminary treatment with an aqueous and/or chemical solution and/or acid.
It is also possible to use this method according to the invention and the described device for cleaning engine pods, lines (to remove coking and oil carbon), the gas path, bearings, bearing chambers, and shafts. For this purpose, the nozzle opening 16 can be directed substantially radially toward the inside. The combustion chamber can thus also be cleaned. For this purpose, at least one injection nozzle is removed, and at least one cleaning nozzle as described here is introduced into the opening that has been uncovered.
For cleaning clogged cooling air bores, for example, of high-pressure turbine rotor blades, it is preferable to use a high-speed nozzle opening (Laval nozzle). An additional advantageous idea is to fill the engine completely or at least to a certain level with cleaning medium (CO 2 ). After the filling, the shaft(s) of the engine is (are) rotated.
If the process parameters described here are increased, then the method can also be used for removing coatings and for stripping paint from components. | The invention relates to a method for cleaning a turbo-machine stage ( 100 ) consisting of at least one of the following steps: a cleaning nozzle ( 1 ) is introduced into an opening of a turbo-machine, in particular into an inspection opening ( 220 ); and the blade ( 100 ) of the stage is acted upon by solid particles, said particles subliming at the blade temperature, in particular into dry ice particles. | 5 |
This is a 35 U.S.C. § 371 of PCT/GB97/02568, filed Sep. 22, 1997.
The present invention describes new compounds. In particular it describes compounds for use in liquid crystal mixtures and in liquid crystal displays (LCDs) or in applications relating to inter alia thermography utilising nematic liquid crystal or chiral nematic liquid crystal mixtures.
BACKGROUND OF THE INVENTION
LCDs, such as multiplexed Twisted Nematic TN-LCDs, Super Twisted Nematic STN-LCDs, Super Birefringent SBE-LCDs, Electrically Controlled Birefringence ECB-LCDs or flexoelectric LCDs are currently used or being developed for computer monitors, laptop or notebook computers, portable telephones, personal digital assistants, etc. The optical, electrical and temporal performance, e.g., contrast, threshold and driving voltages, and response times, of such displays depends crucially on the ratios of the elastic constants (k 33 , k 22 , k 11 ). Currently commercially available nematic mixtures for sophisticated high-information-content LDCs, such as STN-LCDs, generally incorporate trans-1,4-disubstituted-cyclohexyl derivatives with a terminal alkenyl chain (i.e., incorporating a carbon—carbon double bond) directly attached to the cyclohexane ring in order to produce the necessary elastic constant ratios for short response times, high multiplexing rates and low driving voltages. Such materials are costly and difficult to synthesise due to the requirement for a trans configuration of the 1,4-disubstituted cyclohexane ring and the necessity of synthesising the carbon—carbon double bond stepwise from this trans-1,4-disubstituted-cyclohexyl intermediate. If the carbon—carbon double bond is substituted at both carbon atoms, it must have a trans (E) configuration in order to exhibit an advantageous combination of elastic constants and to have an acceptably high nematic-isotropic transition temperature (N- 1 ). The trans configuration is then generally produced by isomerisation of the cis (Z) form generated by the preceding Wittig reaction.
Light crystalline bicyclo[2.2.2]octanes are known and are described in for example G W Gray et al, J. Chem. Soc. Perkin II, (1981), pp 26-31, N Carr et al (1981), Vol 66, pp 267-282, (1985), Vol 129, pp 301-313, R Dabrowski, Mol. Cryst. Liq. Cryst., (1991), Vol 209, pp 201-211, R Dabrowski, Ferroelectrics., (1991), Vol 114, pp 229-240.
For all the above applications it is not usual for a single compound to exhibit all of the properties highlighted, normally mixtures of compounds are used which when mixed together induce the desired phases and required properties.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a matrix multiplex addressed liquid crystal display with associated drivers and controls;
FIG. 2 is a cross-section of a display such as in FIG. 1 used in a transmissive mode; and
FIG. 3 is a cross-section of a display such as in FIG. 1 used in a reflective mode.
According to this invention compounds are provided of Formula I:
wherein:
n may be 0-5;
m may be 1-5;
p may be 1-9;
q may be 0, 1 or 2;
A 1 , A 2 are independently chosen from 1,4-disubstituted benzene, 2,5-disubstituted pyrimidine, or 2,5-disubstituted pyridine, trans-1,4-disubstituted cyclohexane, trans-2,5-disubstituted dioxane; the aromatic rings may be laterally substituted with F, Cl, Br or CN;
Z 1 may be O, COO, OOC;
Z 2 , Z 3 are independently chosen from a direct bond, COO, OOC, C 2 H 4 , CH 2 O, OCH 2 —c≡c—;
provided that when Z 1 is O and m is 1, 3 or 5 the carbon—carbon double bond configuration is E; provided that when Z 1 is O and m is 2 or 4 the carbon—carbon double bond configuration is Z; provided that when Z 1 is COO or OOC and m is 0, 2 or 4 the carbon—carbon double bond configuration is E; and provided that when Z 1 is COO or OOC and m is 1, 3 or 5 the carbon—carbon double bond configuration is Z.
The structural and other preferences are expressed below on the basis of inter alia desirable liquid crystalline characteristics, in particular advantageous elastic constant ratios or flexoelectric coefficients in the nematic phase, a wide nematic phase with a high nematic-isotropic liquid transition temperature, low smetic tendencies and ready synthesis from commercially available starting materials already incorporating the carbon—carbon double bond with the desired configuration and position.
Preferably n is 1-3; Preferably m is 1-3; Preferably n+m is ≦7; Preferably p is 3-7; Preferably q is 0 or 1; Preferably A 1 is 1,4-disubstituted benzene; Preferably A 2 is trans- 1,4-disubstituted cyclohexane; Preferably Z 1 is O or COO; Preferably Z 2 and Z 3 are direct bonds.
Overall preferred structures for formula I are those listed below:
Compounds of formula I can be prepared by various routes. Typically the ethers can be prepared by the Mitsunobu reaction (Synthesis, (1981) pp 1) of a phenol with an alkenyl in the presence of triphenyl phosphine, a dehydrating agent, such as diethyl azodicarboxylate, and a suitable solvent, such as tetrahydrofuran or N,N′-dimethylformamide. Alternatively they can be synthesised by alkylation of a secondary alcohol or phenol with the tosylate of the appropriate alkenol in the presence of a suitable base, such as potassium tert.-butoxide, and a suitable solvent, such as tert.-butyl-methyl ether or 1,2-dimethoxyethane (J. Mater. Chem., (1994) Vol. 4, pp 1673). The esters can be prepared by esterification (Angewandte Chemie (1978) Vol. 90, pp 556) of the appropriate phenol or secondary alcohol with an alkenoic acid in the presence of 4-(dimethylamino)pyridine, a dehydrating agent, such as N,N′-dicyclohexylcarbodiimide, and a suitable solvent, such as dichloromethane or N,N′-dimethylformamide. Alternatively they can be synthesised by esterification of the appropriate phenol or secondary alcohol with an alkenoic acid chloride (produced, for example, from the corresponding alkenoic acid by the action of thionyl chloride or oxalyl chloride) in the presence of a base, such as pyridine or triethylamine, and a suitable solvent, such as toluene or dichloromethane.
In the following examples C signifies the crystalline state, N the nematic phase, I the isotropic phase and ΔT NI the temperature range of the nematic phase.
The invention will now be described, by way of example only, with reference to the following examples and diagrams:
DETAILED DESCRIPTION OF THE INVENTION
EXAMPLE 1
Preparation of 1-(4-[(E)-hex-2-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane
Triphenylphosphine (0.34 g, 0.0013 mol) was added in small portions to a solution of (E)-hex-2-en-1-ol (0.13 g, 0.0013 mol), 4-(4-pentylbicyclo[2.2.2]octyl)phenol (0.35 g, 0.0013 mol), diethylazodicarboxylate (0.22 g, 0.0013 mol) in dry tetrahydrofuran (20 cm 3 ), cooled in an ice bath under an atmosphere of nitrogen. The reaction mixture was stirred at room temperature overnight. The solvent was removed under reduced pressure and the crude product was purified by column chromatography on silica gel using a 9:1 petroleum ether (40-60° C./ethyl acetate mixture as eluent, followed by recrystallisation from ethanol to yield 0.18 g (39%), K 69° C., S A -N 59° C., N-I 134° C.
The following compounds could be obtained analogously:
1-(4-[(E)-But-2-enyloxy]phenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-Pent-2-enyloxy]phenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-Hex-2-enyloxy]phenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-Hept-2-enyloxy]phenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-Oct-2-enyloxy]phenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-But-2-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Pent-2-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Hept-2-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Oct-2-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-But-2-enyloxy]phenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Pent-2-enyloxy]phenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Hex-2-enyloxy]phenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Hept-2-enyloxy]phenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Oct-2-enyloxy]phenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(Z)-Hex-3-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Hex-4-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[Hex-5-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(E)-But-2-enyloxy]biphenyl-4-yl)-4-propylbicyclo[2.2.2]octane. 1-(4′-[(E)-Pent-2-enyloxy]biphenyl-4-yl)-4-propylbicyclo[2.2.2]octane. 1-(4′-[(E)-Hex-2-enyloxy]biphenyl-4-yl)-4-propylbicyclo[2.2.2]octane. 1-(4′-[(E)-Hept-2-enyloxy]biphenyl-4-yl)-4-propylbicyclo[2.2.2]octane. 1-(4′-[(E)-Oct-2-enyloxy]biphenyl-4-yl)-4-propylbicyclo[2.2.2]octane. 1-(4′-[(E)-But-2-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(E)-Pent-2-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(E)-Hex-2-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(E)-Hept-2-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(E)-Oct-2-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(Z)-Hex-3-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(E)-Hex-4-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[Hex-5-enyloxy]biphenyl-4-yl)-4-pentylbicyclo[2.2.2]octane. 1-(4′-[(E)-But-2-enyloxy]biphenyl-4-yl)-4-heptylbicyclo[2.2.2]octane. 1-(4′-[(E)-Pent-2-enyloxy]biphenyl-4-yl)-4-heptylbicyclo[2.2.2]octane. 1-(4′-[(E)-Hex-2-enyloxy]biphenyl-4-yl)-4-heptylbicyclo[2.2.2]octane. 1-(4′-[(E)-Hept-2-enyloxy]biphenyl-4-yl)-4-heptylbicyclo[2.2.2]octane. 1-(4′-[(E)-Oct-2-enyloxy]biphenyl-4-yl)-4-heptylbicyclo[2.2.2]octane.
EXAMPLE 2
Preparation of 4-(4-pentylbicyclo[2.2.2]octyl)phenyl (E)-hex-2-enoate.
A solution of N,N-dicyclohexylcarbodiimide (0.22 g, 1.1 mmol) in dichloromethane (10 cm 3 ) was added to a solution of (E)-hex-2-enoic acid (0.10 g, 0.9 mmol) 4-(4-pentylbicyclo[2.2.2]octyl)phenol (0.24 g, 0.9 mmol), 4-(dimethylamino)pyridine (0.04 g) in dichloromethane (20 cm 3 ), cooled in an ice bath (0° C.) under an atmosphere of nitrogen. The reaction mixture was stirred overnight, filtered to remove precipitated material and the filtrate was evaporated down under reduced pressure. The crude product was purified by column chromatography on silica gel using a 9:1 petroleum ether (40-60° C./ethyl acetate mixture as eluent, followed by recrystallization from ethanol to yield 0.13 g (40%), K 70° C., N-I 134° C.
The following compounds could be obtained analogously:
4-(4-Propylbicyclo[2.2.2]octyl)phenyl (E)-but-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)phenyl (E)-pent-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)phenyl (E)-hex-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)phenyl (E)-hept-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)phenyl (E)-oct-2-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)phenyl (E)-but-2-enoate, K 76° C., N-I 154° C. 4-(4-Pentylbicyclo[2.2.2]octyl)phenyl (E)-pent-2-enoate, K 72° C., N-I 130° C. 4-(4-Pentylbicyclo[2.2.2]octyl)phenyl (E)-hept-2-enoate, K 49° C., N-I 121° C. 4-(4-Pentylbicyclo[2.2.2]octyl)phenyl (E)-oct-2-enoate, K 63° C., N-I 122° C. 4-(4-Heptylbicyclo[2.2.2]octyl)phenyl (E)-but-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)phenyl (E)-pent-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)phenyl (E)-hex-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)phenyl (E)-hept-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)phenyl (E)-oct-2-enoate. 4-(4-Hexylbicyclo[2.2.2]octyl)phenyl (Z)-hex-3-enoate. 4-(4-Hexylbicyclo[2.2.2]octyl)phenyl (E)-hex-4-enoate. 4-(4-Hexylbicyclo[2.2.2]octyl)phenyl hex-5-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)phenyl-4′-yl (E)-but-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-pent-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-hex-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-hept-2-enoate. 4-(4-Propylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-oct-2-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-but-2-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-pent-2-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-hex-2-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-hept-2-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-oct-2-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl (Z)-hex-3-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-hex-4-enoate. 4-(4-Pentylbicyclo[2.2.2]octyl)biphenyl-4′-yl hex-5-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-but-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-pent-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-hex-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-hept-2-enoate. 4-(4-Heptylbicyclo[2.2.2]octyl)biphenyl-4′-yl (E)-oct-2-enoate. 1-[4-(trans-5-[(E)-But-2-enoyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Pent-2-enoyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Hept-2-enoyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Oct-2-enoyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(Z)-Hex-3-enoyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Hex-4-enoyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[Hex-5-enoyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane.
EXAMPLE 3
Preparation of 1-[4-(trans-4-[(E)-hex-2-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane
A mixture of toluene-4-sulfonic acid (E)-hex-2-en-1-yl ester (1.0 g, 2.8 mmol), 1-[4-(trans-4-hydroxycyclohexyl) phenyl]-4-pentylbicyclo[2.2.2]octane (0.50 g, 1.4 mmol), potassium tert-butoxide (0.55 g, 4.5 mmol) and 1,2-dimethoxyethane (20 cm 3 ) is stirred at room temperature overnight, filtered to remove inorganic material diluted with water (100 cm 3 ) and then extracted into diethyl ether (3×50 cm 3 ). The combined organic extracts are washed with water (2×100 cm 3 ), dried (MgSO 4 ), filtered and then evaporated down. The residue is purified by column chromatography on silica gel using a 9:1 hexane/ethyl acetate mixture as eluent and recrystallisation from ethanol to yield 0.25 g (66%) of the desired ether.
The toluene-4-sulfonic acid (E)-hex-2-en-1-yl ester and 1-[4-(trans-4-hydroxycyclohexyl) phenyl]-4-pentylbicyclo[2.2.2]octane required as starting materials could be prepared as follows:
(a). A solution of toluene-4-sulfonyl chloride (0.75 g, 4.0 mmol) in dichloromethane (10 cm 3 ) is added slowly to a solution of (E)-hex-2-en-1-ol (0.39 g, 4.0 mmol), triethylamine (0.80 g, 8.0 mmol) and dichloromethane (50 cm 3 ) at 0° C. The reaction mixture is stirred at 0° C. for 6 h, washed with dilute hydrochloric acid (2×50 cm 3 ), water (2×50 cm 3 ) and dilute sodium carbonate solution (2×50 cm 3 ), dried (MgSO 4 ), filtered and then evaporated down to yield 1.0 g (99%) of the desired tosylate, which is used without further purification.
(b). A solution of 1-bromo-4-pentylbicyclo[2.2.2]octane (6 g, 23 mmol) in sieve-dried nitrobenzene (100 cm 3 ) is added dropwise to a stirred solution of 4-phenylcyclohexanone (3.9 g, 23 mmol) and anhydrous iron(III)chloride (1.2 g, 9 mmol) in sieve-dried nitrobenzene (100 cm 3 ) maintained at 80° C. through the addition and overnight. The cooled solution is added to a small volume of hydrochloric acid and stirred for 20 min. The organic layer is separated off and steam-distilled to yield a solid residue. This is taken up in dichloromethane and dried (MgSO 4 ). The raw product is crystallised from ethanol to yield the desired 4-[4-(4-pentylbicyclo[2.2.2]octyl)phenyl]cyclohexanone (5.4 g, 69%).
(c). 4-[4-(4-pentylbicyclo[2.2.2]octyl)penyl]cyclohexanone (1.5 g, 4.3 mmol) and a mixture of 9:1 methanol/ether (25 cm 3 ) is added dropwise to a freshly prepared mixture of sodium borohydride (1.2 g, 8.5 mmol) and a mixture of 9:1 methanol/ether (25 cm 3 ) at 0° C. When the addition is complete, the reaction mixture is stirred overnight at room temperature. A 25 per cent hydrochloric acid solution is added carefully to the reaction mixture, which was extracted into ethyl acetate (3×50 cm 3 ). The combined organic extracts are washed with water (2×500 ml) and dilute sodium carbonate solution (2×500 ml), dried (MgSO 4 ), filtered and then evaporated down. The residue is purified by column chromatography on silica gel using a 7:3 hexane/ethyl acetate mixture as eluent and recrystallisation from ethanol to yield the pure 1-[4-(trans-4-hydroxycyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane (1.2 g, 80 per cent).
The following compounds could be obtained analogously:
1-[4-(trans-4[(E)-But-2-enyloxy]cyclohexyl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Pent-2-enyloxy]cyclohexyl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Hept-2-enyloxy]cyclohexyl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Oct-2-enyloxy]cyclohexyl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-But-2-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Pent-2-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Hept-2-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Oct-2-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(Z)-Hex-3-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Hex-4-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-4-[Hex-5-enyloxy]cyclohexyl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-But-2-enyloxy]cyclohexyl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Pent-2-enyloxy]cyclohexyl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Hept-2-enyloxy]cyclohexyl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(trans-4-[(E)-Oct-2-enyloxy]cyclohexyl)phenyl]-4-heptylbicyclo[2.2.2]octane.
EXAMPLE 4
Preparation of trans-4-[4-(4-pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl (E)-hex-2-enoate
A solution of N,N-dicyclohexylcarbodiimide (0.22 g, 1.1 mmol) in dichloromethane (10 cm 3 ) is added to a solution of (E)-hex-2-enoic acid (0.10 g, 0.9 mmol), 1-[4-(trans-4-hydroxycyclohexyl) phenyl]-4-pentylbicyclo[2.2.2]octane (0.32 g, 0.9 mmol), 4-(dimethylamino) pyridine (0.04 g) in dichloromethane (20 cm 3 ), cooled in an ice bath (0° C.) under an atmosphere of nitrogen. The reaction mixture is stirred overnight, filtered to remove precipitated material and the filtrate is evaporated down under reduced pressure. The crude product is purified by column chromatography on silica gel using a 9:1 petroleum ether (40-60° C.)/ethyl acetate mixture as eluent, followed by recrystallization from ethanol to yield the desired ester (0.26 g, 64%).
The following compounds could be obtained analogously:
trans-4-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl (E)-but-2-enoate. trans-4-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl (E)-pent-2-enoate. trans-4-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl (E)-hept-2-enoate. trans-4-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl (E)-oct-2-enoate. trans-4-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl (Z)-hex-3-enoate. trans-4-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl (E)-hex-4-enoate. trans-4-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]cyclohexyl hex-5-enoate.
EXAMPLE 5
Preparation of 1-[4-(5-[(E)-hex-2-enyloxy]pyrimidin-2-yl)phenyl]-4-pentylbicyclo [2.2.2]octane.
Triphenylphosphine (0.34 g, 1.3 mmol) is added in small portions to a solution of (E)-hex-2-Triphenylphosphine (0.34 g, 1.3 mmol), 1-[4-(5-hydroxypyrimidin-2-yl)phenyl]-4-pentylbicyclo [2.2.2]octane (0.38 g, 1.3 mmol), diethylazodicarboxylate (0.22 g, 1.3 mmol) in dry tetrahydrofuran (20 cm 3 ), cooled in an ice bath under an atmospher of nitrogen. The reaction mixture is stirred at room temperature overnight. The solvent is removed under reduced pressure and the crude product is purified by column chromatography on silica gel using a 9:1 petroleum ether (40-60° C.)/ethyl acetate mixture as eluent, followed by recrystallisation from ethanol to yield 0.24 g (44%) of the ether.
The 1-[4-(5-hydroxypyrimidin-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane required as starting material could be prepared as follows:
(a). A solution of 4-(4-pentylbicyclo[2.2.2]octyl)benzonitrile (50.0 g, 170 mmol) in ethanol (35 cm 3 ) and toluene (200 cm 3 ) is saturated with hydrogen chloride at 0° C. and then stirred at room temperature for 2 days. The reaction mixture is evaporated down under reduced pressure, shaken with ether (500 cm 3 ), filtered, washed with portions of ether and finally dried under vacuum to yield 57.6 g (89%) of 4-(4-pentylbicyclo [2.2.2]octyl)phenylimidoethylether hydrochloride.
(b). A saturated ethanolic ammonia solution 350 cm 3 ) is added to a solution of 4-(4-pentylbicyclo [2.2.2]octyl)phenylimidoethylether hydrochloride (57.6 g, 153 mmol) and ethanol (350 cm 3 ). The reaction mixture is stirred at room temperature for 2 days and then evaporated. The solid residue is shaken with ether (500 cm 3 ), filtered, washed with portions of ether and finally dried under vacuum to yield 50.2 g (94%) of 4-(4-pentylbicyclo [2.2.2]octyl)benzamidine hydrochloride.
(c). A 5.4 molar solution of sodium methoxide in methanol (40 cm 3 ) is added dropwise to a mixture of (4-[benzyloxy]phenyl)-(2-methoxymethylidene)ethanal (146 mmol), 4-(4-pentylbicyclo [2.2.2]octyl)benzamidine hydrochloride (50.2 g, 146 mmol) and methanol (160 cm 3 ) at room temperature, stirred overnight and added to water an extracted with dichloromethane (3×100 cm 3 ). The combined organic layers are washed with water (500 cm 3 ), dilute potassium carbonate (200 cm 3 ) and once again with water (500 cm 3 ) then dried (mgSO 4 ), filtered and evaporated. The residue is purified by column chromatography (flash) on silica gel using a 97:3 dichloromethane/methanol mixture as eluent followed by recrystallisation from ethyl acetate to yield the desired ether (38.5 g, 70%).
(d). A one molar solution of boron tribromide (120 cm 3 ) is added dropwise to a solution 1-[4-(5-benzyloxypyrimidin-2-yl) phenyl]-4-pentylbicyclo[2.2.2]octane (38.5 g, 100 mmol) in dichloromethane (200 cm 3 ) and cooled using an ice bath. The reaction is stirred overnight at room temperature and then poured onto an ice/water mixture (500 g). The organic layer is separated off and the aqueous layer extracted with dichloromethane (3×100 cm 3 ). The combined organic layers are washed with water (500 cm 3 ), dilute potassium carbonate (200 cm 3 ) and once again with water (500 cm 3 ) then dried (MgSO 4 ), filtered and evaporated. The residue is purified by column chromatography (flash) on silica gel using a 97:3 dichloromethane/methanol mixture as eluent followed by recrystallisation from ethyl acetate to give the 1-[4-(5-hydroxypyrimidin-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane (14.7 g, 50%).
The following compounds could be obtained analogously:
1-[4-(5-[(E)-But-2-enyloxy]pyrimidin-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Pent-2-enyloxy]pyrimidin-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Hex-2-enyloxy]pyrimidin-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Hept-2-enyloxy]pyrimidin-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Oct-2-enyloxy]pyrimidin-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-But-2-enyloxy]pyrimidin-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Pent-2-enyloxy]pyrimidin-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Hept-2-enyloxy]pyrimidin-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Oct-2-enyloxy]pyrimidin-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-But-2-enyloxy]pyrimidin-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Pent-2-enyloxy]pyrimidin-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Hex-2-enyloxy]pyrimidin-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Hept-2-enyloxy]pyrimidin-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(5-[(E)-Oct-2-enyloxy]pyrimidin-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane.
EXAMPLE 6
Preparation of 2-[4-(4-pentylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-hex-2-enoate
A solution of N,N-dicyclohexylcarbodiimide (0.22 g, 1.1 mmol) in dichloromethane (10 cm 3 ) is added to a solution of (E)-hex-2-enoic acid (0.10 g, 0.9 mmol), 1-[4-(5-hydroxypyrimidin-2-yl) phenyl]-4-pentylbicyclo[2.2.2]octane (0.25 g, 0.9 mmol), 4-(dimethylamino)pyridine (0.04 g) in dichloromethane (20 cm 3 ), cooled in an ice bath (0° C.) under an atmosphere of nitrogen. The reaction mixture is stirred overnight, filtered to remove precipitated material and the filtrate is evaporated down under reduced pressure. The crude product is purified by column chromatography on silica gel using a 9:1 petroleum ether (40-60° C.)/ethyl acetate mixture as eluent, followed by recrystallisation from ethanol to yield the desired ester (0.15 g, 45%).
The following compounds could be obtained analogously:
2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-but-2-enoate. 2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-pent-2-enoate. 2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-hex-2-enoate. 2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-hept-2-enoate. 2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-oct-2-enoate. 2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-but-2-enoate. 2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-pent-2-enoate. 2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-hept-2-enoate. 2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-oct-2-enoate. 2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-but-2-enoate. 2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-pent-2-enoate. 2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-hex-2-enoate. 2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-hept-2-enoate. 2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]pyrimidin-5-yl (E)-oct-2-enoate.
EXAMPLE 7
Preparation of 1-[4-(trans-5-[(E)-hex-2-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo [2.2.2]octane.
A mixture of toluene-4-sulfonic acid (E)-hex-2-en-1-yl ester (1.0 g, 2.8 mmol), 1-[4-(trans-5-hydroxydioxan-2-yl) phenyl]-4-pentylbicyclo[2.2.2]octane (0.50 g, 1.4 mmol), potassium tert-butoxide (0.55 g, 4.5 mmol) and 1,2-dimethoxyethane (50 cm 3 ) is stirred at room temperature overnight, filtered to remove inorganic material, diluted with water (500 cm 3 ) and then extracted into diethyl ether (3×100 cm 3 ). The combined organic extracts are washed with water (2×500 cm 3 ), dried (MgSO 4 ), filtered and then evaporated down. The residue is purified by column chromatography on silica gel using a 9:1 hexane/ethyl acetate mixture as eluent and recrystallisation from ethanol to yield 0.25 g (66%) of the desired ether.
The 1-[4-(trans-5-hydroxydioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane required as starting materials could be prepared as follows:
(a). A solution of diisobutyl aluminium hydride (20% v/v) in toluene (100 cm 3 ) is added dropwise to a solution of 4-(4-pentylbicyclo[2.2.2]octyl)benzonitrile (5.5 g, 45 mmol) at 0° C. After completion of the addition the reaction solution is allowed to regain room temperature slowly and is stirred at this temperature overnight. The reaction solution is cooled to 0° C. and cold 1N sulphuric acid (500 cm 3 ) is added carefully. The organic phase is separated off and the aqueous phase extracted with toluene (3×100 cm 3 ). The combined organic phases are washed with water (2×100 cm 3 ), dried (MgSO 4 ) and finally evaporated down under reduced pressure. The residue is purified by recrystallisation from ethyl acetate to give 2.5 g (45%) of the pure aldehyde.
(b). A solution of 4-(4-pentylbicyclo[2.2.2]octyl)benzaldehyde (2.5 g, 8.5 mmol), glycerol (1.0 g, 8.5 mmol), pyridinium-(toluyl-4-sulphonate) (0.2 g) and toluene is heated for over 2 h so that the toluene/water mixture generated is continuously distilled off. The solution is evaporated down and the residue purified by column chromatography on silica gel using a 7:3 hexane/ethyl acetate mixture as eluent and recrystallisation from ethanol to yield 0.75 g (25%) of the 1-[4-(trans-5-hydroxydioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane.
The following compounds could be obtained analogously:
1-[4-(trans-5-[(E)-But-2-enyloxy]dioxan-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Pent-2-enyloxy]dioxan-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Hept-2-enyloxy]dioxan-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Oct-2-enyloxy]dioxan-2-yl)phenyl]-4-propylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-But-2-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Pent-2-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Hept-2-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Oct-2-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(Z)-Hex-3-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Hex-4-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[Hex-5-enyloxy]dioxan-2-yl)phenyl]-4-pentylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-But-2-enyloxy]dioxan-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Pent-2-enyloxy]dioxan-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Hept-2-enyloxy]dioxan-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane. 1-[4-(trans-5-[(E)-Oct-2-enyloxy]dioxan-2-yl)phenyl]-4-heptylbicyclo[2.2.2]octane.
EXAMPLE 8
Preparation of trans-2-[4-(4-pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-hex-2-enoate
A solution of N,N-dicyclohexylcarbodiimide (0.18 g, 0.8 mmol) in dichloromethane (10 cm 3 ) is added to a solution of (E)-hex-2-enoic acid (0.07 g, 0.7 mmol), 1-[4-(trans-5-hydroxydioxan-2-yl) phenyl]-4-pentylbicyclo[2.2.2]octane (0.25 g, 0.7 mmol), 4-(dimethylamino) pyridine (0.04 g) in dichloromethane (20 cm 3 ), cooled in an ice bath (0° C.) under an atmosphere of nitrogen. The reaction mixture is stirred overnight, filtered to remove precipitated material and the filtrate was evaporated down under reduced pressure. The crude product is purified by column chromatography on silica gel using a 9:1 petroleum ether (40-60° C.)/ethyl acetate mixture as eluent, followed by recrystallisation from ethanol to yield the desired ester.
The following compounds could be obtained analogously:
trans-2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-but-2-enoate. trans-2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-pent-2-enoate. trans-2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-hex-2-enoate. trans-2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-hept-2-enoate. trans-2-[4-(4-Propylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-oct-2-enoate. trans-2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-but-2-enoate. trans-2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-pent-2-enoate. trans-2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-hept-2-enoate. trans-2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-oct-2-enoate. trans-2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (Z)-hex-3-enoate. trans-2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-hex-4-enoate. trans-2-[4-(4-Pentylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl hex-5-enoate. trans-2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-but-2-enoate. trans-2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-pent-2-enoate. trans-2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-hex-2-enoate. trans-2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-hept-2-enoate. trans-2-[4-(4-Heptylbicyclo[2.2.2]octyl)phenyl]dioxan-5-yl (E)-oct-2-enoate.
EXAMPLE 9
Preparation of 1-(2, 3-difluoro-4-[(E)-hex-2-enyloxy]phenyl)-4-pentylbicyclo[2.2.2]octane
Triphenylphosphine (0.34 g, 1.3 mmol) is added in small portions to a solution of (E)-hex-2-en-1-ol (0.13 g, 1.3 mmol), 2, 3-difluoro-4-(4-pentylbicyclo[2.2.2]octyl)phenyl (0.40 g, 1.3 mmol), diethylazodicarboxylate (0.22 g, 1.3 mmol) in dry tetrahydrofuran (20 cm 3 ), cooled in an ice bath under an atmosphere of nitrogen. The reaction mixture is stirred at room temperature overnight. The solvent is removed under reduced pressure and the crude product is purified by column chromatography on silica gel using a 9:1 petroleum ether (40-60° C.)/ethyl acetate mixture as eluent, followed by recrystallisation from ethanol to yield 0.22 g (43%).
(a). A solution of 1-bromo-4-pentylbicyclo[2.2.2]octane (6 g, 23 mmol) in sieve-dried nitrobenzene (100 cm 3 ) is added dropwise to a stirred solution of 2, 3-difluoro-4-methoxybenzene (6 g, 23 mmol) and anhydrous iron(III)chloride (1.2 g, 9 mmol) in sieve-dried nitrobenzene (100 cm 3 ) maintained at 80° C. throughout the addition and overnight. The cooled solution is added to a small volume of hydrochloric acid and stirred for 20 min. The organic layer is separated off and steam-distilled to yield a solid residue. This is taken up in dichloromethane and dried (MgSO 4 ). The raw product is crystallised from ethanol to yield the desired 2, 3-difluoro-1-methoxy-4-(4-pentylbicyclo[2.2.2]octyl)benzene (3.2 g, 44%)
(b). A one molar solution of boron tribromide (10 cm 3 ) is added dropwise to a solution of 2, 3-difluoro-1-methoxy-4-(4-pentylbicyclo[2.2.2]octyl)benzene (3.2 g, 1.0 mmol) in dichloromethane (50 cm 3 ) and cooled using an ice bath. The reaction is stirred overnight at room temperature and then poured onto an ice/water mixture (100 g). The organic layer is separated off and the aqueous layer extracted with dichloromethane (3×50 cm 3 ). The combined organic layers are washed with water (100 cm 3 ), dilute potassium carbonate (100 cm 3 ) and once again with water (100 cm 3 ) then dried (MgSO 4 ), filtered and evaporated. The residue is purified by column chromatography (flash) on silica gel using a 97:3 dichloromethane/methanol mixture as eluent followed by recrystallisation from ethyl acetate to give the phenol (yield 2.2 g, 72%).
The following compounds could be obtained analogously:
1-(4-[(E)-But-2-enoyloxy]-2, 3-difluorophenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-Pent-2-enoyloxy]-2, 3-difluorophenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-Hept-2-enoyloxy]-2, 3-difluorophenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-Oct-2-enoyloxy]-2, 3-difluorophenyl)-4-propylbicyclo[2.2.2]octane. 1-(4-[(E)-But-2-enoyloxy]-2, 3-difluorophenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Pent-2-enoyloxy]-2, 3-difluorophenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Hex-2-enoyloxy]-2, 3-difluorophenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Hept-2-enoyloxy]-2, 3-difluorophenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-Oct-2-enoyloxy]-2, 3-difluorophenyl)-4-pentylbicyclo[2.2.2]octane. 1-(4-[(E)-But-2-enoyloxy]-2, 3-difluorophenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Pent-2-enoyloxy]-2, 3-difluorophenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Hex-2-enoyloxy]-2, 3-difluorophenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Hept-2-enoyloxy]-2, 3-difluorophenyl)-4-heptylbicyclo[2.2.2]octane. 1-(4-[(E)-Oct-2-enoyloxy]-2, 3-difluorophenyl)-4-heptylbicyclo[2.2.2]octane.
TABLE 1
Transition temperatures for the 1-(4-[(E)-alk-2-enoyloxy]phenyl)-4-
pentylbicyclo[2.2.2]octanes
(E)
Compound
n
C—N/° C.
N—I/° C.
ΔT NI /° C.
1
76
154
78
2
72
130
58
3
70
134
64
4
49
121
72
5
63
122
59
TABLE 2
Transition temperatures for the 1-[4-(octanoyloxy)phenyl]-4-
pentylbicyclo[2.2.2]octane and the 1-[4-([E]-oct-2-enoyloxy)phenyl]-4-
pentylbicyclo[2.2.2]octanes
Compound
R
C—N/° C.
N—I/° C.
ΔT NI /° C.
84
87
3
(E)
63
122
59
TABLE 3
Transition temperatures for the bicyclo [2.2.2]octanes
Compound
R
C—N/° C.
S B -N/° C.
S A -N/° C.
N—I/° C.
(E)
69
—
(59)
83
66
(54)
—
79
() represents a monotropic transition temperature
The following birefringence data was obtained:
Wt/% in ZLI3086=10
Ext Δn 30° C.= 0 . 128
Ext Δn 20° C.= 0 . 133
Ext Δn T/T NI =0.8=0.128
wherein Ext Δn is a linear extrapolation in concentration of the birefringence in ZL13086 which is a commercially available (from Merck UK) apolar nematic host mixture. T is the temperature at which the measurement was taken (in Kelvin) and T N is the phase transition for the nematic-isotropic phase change (in Kelvin).
One known device in which the materials of the current invention may be incorporated is the twisted nematic device which uses a thin layer of a nematic material between glass slides. The slides are unidirectionally rubbed and assembled with the rubbing directions orthogonal. The rubbing gives a surface alignment to the liquid crystal molecules resulting in a progressive 90° twist across the layer. When placed between polarisers, with their optical axis perpendicular or parallel to a rubbing direction the device rotates the plane of polarised light in its OFF state and transmits without rotation in the ON state. Small amounts of cholesteric material may be added to the nematic material to ensure the 90° twist is of the same sense across the whole area of the device as explained in UK patents 1,472,247 and 1,478,592.
An improvement in the performance of large, complex, nematic LCDs occurred in 1982 when it was observed that the voltage dependence of the transmission of nematic LC layers with twist angles in the range 180° to 270° could become infinitely steep, see C. M. Waters, V. Brimmell and E. P. Raynes, Proc. 3rd Int. Display Res. Conf. Kobe, Japan, 1983, 396. The larger twist angles are produced by a combination of surface alignment and making the nematic mixture into a long pitch cholesteric by the addition of a small amount of a chiral twisting agent. The increasing twist angle steepens the transmission/voltage curve, until it becomes bistable for 270° 0 twist; for a specific twist angle between 225° and 270° 0 the curve becomes infinitely steep and well suited to multiplexing. The larger twist angles present have resulted in the name supertwisted nematic (STN) for the LCDs.
Liquid Crystal Devices describing the use of STNs may be found in patent application GB 8218821 and resulting granted patents including U.S. Pat. No. 4,596,446.
The display of FIGS. 1 and 2 comprises a liquid crystal cell 1 formed by a layer 2 of cholesteric liquid crystal material contained between glass walls 3 , 4 . A spacer ring 5 maintains the walls typically 6 μm apart. Strip like row electrodes 6 1 to 6 m , e.g. of SnO 2 are formed on one wall 3 and similar column electrodes 7 1 to 7 n formed on the other wall 4 . With m-row electrodes and n-column electrodes this forms an mxn matrix of addressable elements. Each element is formed by the interaction of a row and column electrode.
A row driver supplies voltage to each row electrode 6 . Similarly a column drive 9 supplies voltages to each column electrode 7 . Control of applied voltages is from a control logic 10 which receives power from a voltage source 11 and timing from a clock 12 .
An example of the use of a material and device embodying the present invention will now be described with reference to FIG. 2 .
The liquid crystal device consists of two transparent plates, 3 and 4 , for example made from glass. These plates are coated on their internal face with transparent conducting electrodes 6 and 7 . An alignment layer is introduced onto the internal faces of the cell so that a planar orientation of the molecules making up the liquid crystalline material will be approximately parallel to the glass plates 3 and 4 . This is done by coating the glass plates 3 , 4 complete with conducting electrodes so that the intersections between each column and row form an x, y matrix of addressable elements or pixels. For some types of display the alignment directions are orthogonal. Prior to the construction of the cell the alignment layers are rubbed with a roller covered in cloth (for example made from velvet) in a given direction, the rubbing directions being arranged parallel (same or opposite direction) upon construction of the cell. A spacer 5 e.g. of polymethyl methacrylate separates the glass plates 3 and 4 to a suitable distance e.g. 2 microns. Liquid crystal material 2 is introduced between glass plates 3 , 4 by filling the space in between them. This may be done by flow filling the cell using standard techniques. The spacer 5 is sealed with an adhesive in a vacuum using an existing technique. Polarisers 13 may be arranged in front of and behind the cell.
Alignment layers may be introduced into one or more of the cell walls by one or more of the standard surface treatment techniques such as rubbing, oblique evaporation or as described above by the use of polymer aligning layers.
In alternative embodiments the substrates with the aligning layers on them are heated and sheared to induce alignment, alternatively the substrates with the aligning layers are thermally annealed above the glass transition temperature and below the liquid crystal to isotropic phase transition in combination with an applied field. Further embodiments may involve a combination of these aligning techniques. With some of these combinations an alignment layer may not be necessary.
The device may operate in a transmissive or reflective mode. In the former, light passing through the device, e.g. from a tungsten bulb, is selectively transmitted or blocked to form the desired display. In the reflective mode a mirror, or diffuse reflector, ( 16 ) is placed behind the second polariser 13 to reflect ambient light back through the cell and two polarisers. By making the mirror partly reflecting the device may be operated both in a transmissive and reflective mode.
The alignment layers have two functions, one to align contacting liquid crystal molecules in a preferred direction and the other to give a tilt to these molecules—a so called surface tilt—of a few degrees typically around 4° or 5°. The alignment layers may be formed by placing a few drops of the polyimide on to the cell wall and spinning the wall until a uniform thickness is obtained. The polyimide is then cured by heating to a predetermined temperature for a predetermined time followed by unidirectional rubbing with a roller coated with a nylon cloth.
In an alternative embodiment a single polariser and dye material may be combined.
Cholesteric or chiral nematic liquid crystals possess a twisted helical structure which is capable of responding to a temperature change through a change in the helical pitch length. Therefore as the temperature is changed then the wavelength of the light reflected from the planar cholesteric structure will change and if the reflected light covers the visible range then distinct changes in colour occur as the temperature varies. This means that there are many possible applications including the areas of thermography and thermooptics.
The cholesteric mesophase differs from the nematic phase in that in the cholesteric phase the director is not constant in space but undergoes a helical distortion. The pitch length for the helix is a measure of the distance for the director to turn through 360°.
By definition, a cholesteric material is chiral material. Cholesteric materials may also be used in electro-optical displays as dopants, for example in twisted nematic displays where they may be used to remove reverse twist defects, they may also be used in cholesteric to nematic dyed phase change displays where they may be used to enhance contrast by preventing wave-guiding.
Thermochromic applications of cholesteric liquid crystal materials usually use thin film preparations of the cholesterogen which are then viewed against a black background. These temperature sensing devices may be placed into a number of applications involving thermometry, medical thermography, non-destructive testing, radiation sensing and for decorative purposes. Examples of these may be found in D G McDonnell in Thermotropic Liquid Crystals, Critical Reports on Applied Chemistry, Vol 22, edited by G W Gray, 1987 pp 120-44; this reference also contains a general description of thermochromic cholesteric liquid crystals.
Generally, commercial thermochromic applications require the formulation of mixtures which possess low melting points, short pitch lengths and smectic transitions just below the required temperature-sensing region. Preferably the mixture or material should retain a low melting point and high smectic-cholesteric transition temperatures.
In general, thermochromic liquid crystal devices have a thin film of cholesterogen sandwiched between a transparent supporting substrate and a black absorbing layer. One of the fabrication methods involves producing an ‘ink’ with the liquid crystal by encapsulating it in a polymer and using printing technologies to apply it to the supporting substrate. Methods of manufacturing the inks include gelatin microencasulation, U.S. Pat. No. 3,585,318 and polymer dispersion, U.S. Pat. Nos. 1,161,039 and 3,872,050. One of the ways for preparing well-aligned thin-film structures of cholesteric liquid crystals involves laminating the liquid crystal between two embossed plastic sheets. This technique is described in UK patent 2,143,323.
For a review of thermochromism in liquid crystals see J G Grabmaier in ‘Applications of Liquid Crystals’, G Meier, E Sackmann and J G Grabmaier, Springer-Verlag, Berlin and New York, 1975, pp 83-158.
The materials of the current invention may be used in many of the known devices including those mentioned in the introduction. | Compounds of formula (I)
are provided which are particularly useful in super twisted nematic devices, where n may be 0-5; m may be 0-5; p may be 1-9; q may be 1, 1, or 2; A 1 , A 2 are independently chosen from 1-4, -disubstituted benzene, 2,5-disubstituted pyrimidine, or 2,5-disubstituted pyridine, trans- 1,4-disubstituted cyclohexane, trans- 2,5-disubstitued dioxane. The aromatic rings may be laterally substituted with F, Cl, Br or CN; Z 1 may be O, COO, OOC; Z 2 , Z 3 are independent chosen from a direct bond, COO, OOC, C 2 H 4 , CH 2 O, OCH 2 , or -c≡c-, provided that when Z 1 is O and m is 1, 3 or 5 the carbon—carbon double bond configuration is E; provided that when Z 1 is O and m is 2 or 4 the carbon—carbon double bond configuration is Z; provided that when Z 1 is COO or OOC and m is 0, 2 or 4 the carbon—carbon double bond configuration is E; and provided that when Z 1 is COO or OOC and m is 1, 3 or 5 the carbon—carbon double bond configuration is Z. | 2 |
BACKGROUND OF THE INVENTION
The present invention provides novel compounds, novel compositions, methods of their use and methods of their manufacture, such compounds pharmacologically useful in the treatment of cardiac arrhythmias. More specifically, the compounds of the present invention are Class III antiarrhythmic agents which, by effectively prolonging repolarization of a cardiac cell action potential, can be used effectively to treat certain cardiac arrhythmias.
Antiarrhythmic drugs have been grouped together according to the pattern of electrophysiological effects that they produce and/or their presumed mechanisms of action. Thus, Class I antiarrhythmic agents are characterized by being sodium channel blockers, Class II antiarrhythmic agents are beta adrenergic blockers, Class III antiarrhythmic agents prolong repolarization, and Class IV antiarrhythmic agents are calcium channel blockers.
Currently, there are very few Class III antiarrhythmic agents available for therapeutic use. Among them is bretylium. Bretylium's usefulness is limited, however, and currently its theraputic use is reserved for life-threatening ventricular arrhythmias that are refractory to other therapy. Thus, bretylium's use is generally confined to intensive care units. It is an object of this invention to provide Class III antiarrhythmic agents of broader theraputic use than existing Class III antiarrhythmic agents.
SUMMARY OF THE INVENTION
The invention relates to novel compounds of the general formula I: ##STR1## the pharmaceutically acceptable non toxic salts thereof and the hydrated forms thereof,
wherein R 1 is alkyl, alkenyl or alkynyl of from one to ten carbon atoms; substituted or unsubstituted aralkyl, aralkenyl or aralkynyl of from one to ten carbon atoms and wherein said aryl substituent is one or more of alkoxy, nitro, halogen or alkylsulfonamide at any position with alkoxy or alkylsulfonamide having alkyl, alkenyl or alkynyl of one to ten carbon atoms; alkyl, alkenyl or alkynyl of from one to ten carbon atoms substituted by furanyl, imidazolyl, pyridinyl, or imidazolyl substituted by alkoxycarbonyl having alkyl, alkenyl or alkynyl of one to ten carbon atoms; arylamino; substituted aryl, unsubstituted aryl or either of them fused to substituted or unsubstituted cycloalkyl of from three to eight carbon atoms wherein said cycloalkyl substituent can be halogen; unsubstituted cycloalkyl of from three to eight carbon atoms arylcyloalkyl wherein cycloalkyl is from three to eight carbon atoms; pyridinyl; furanyl; halogen substituted furanyl; substituted or unsubstituted benzofuranyl wherein said benzofuranyl substituent can be one or more at any position of halogen, amino, nitro or alkoxy having alkyl, alkenyl or alkynyl of from one to ten carbon atoms; substituted or unsubstituted benzopyranyl wherein said substituent can be keto; thiophene; benzothiophene; or substituted or unsubstituted indene or isoindene wherein said substituent is alkyl of one to ten carbon atoms;
n is an integer of from one to ten;
R 2 is unsubstituted or is alkyl, alkenyl or alkynyl of from one to ten carbon atoms or oxygen that is present as an N-oxide; R 3 is hydrogen, carboxyalkyl, carboxy alkenyl or carboxy alkynyl of from one to ten carbon atoms or alkoxycarbonylalkyl, alkoxycarbonylalkenyl or alkoxycarbonylalkynyl and wherein the alkoxy moiety can have alkyl, alkenyl or alkynyl of from one to ten carbon atoms; ##STR2## is hydrogen; pyridinyl; cycloalkyl of three to eight carbon atoms or hydroxy substituted cycloalkyl of three to eight carbon atoms; furanyl; or unsubstituted or substituted phenyl wherein said phenyl substituent is one or more of alkyl or halogen substituted alkyl of one to ten carbon atoms, alkoxy from one to ten carbon atoms, nitro, amine, mono or di alkylamine, acetyl amine, acetylamide, halogen or alkoxy itself substituted by halogen substituted phenyl; and R 4 is alkoxycarbonyl of from one to ten carbon atoms.
The compounds and pharmaceutical compositions thereof are useful in the antiarrhythmic methods of the invention. The invention further provides dosage unit forms adapted for oral, topical and parenteral administration. Also provided for in this invention are the pharmaceutically acceptable salts of the compounds.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, the term "alkyl" shall mean straight or branched chain carbon-carbon linkages of from one to ten carbon atoms. "Alkenyl" shall have the same meaning, except that one or more double bonds may be present therein. "Alkynyl" shall have the same meaning, except that one or more triple bonds may be present therein.
"Alkoxy" shall include alkyl, alkenyl and alkynyl, as defined above, substituted by an epoxide oxygen.
"Aralkyl" shall include alkyl, alkenyl and alkynyl, as defined above, substituted by an aryl group, which is defined below.
"Aryl" shall mean phenyl.
"Halogen" shall include fluorine, chlorine, bromine or iodine.
The term "cardiac arrhythmia" is defined to mean any variation from the normal rhythm of the heartbeat, including, without limitation, sinus arrhythmia, premature heartbeat, heartblock, fibrillation, flutter, pulsus alternans, tachycardia, paroxysmal tachycardia and premature ventricular contractions.
The term "repolarization of cardiac cells" is defined as those phases of a cardiac action potential during which time a depolarized cardiac cell is reverting to normal pre-polarization transmembrane voltage.
The term "pharmaceutically acceptable salts" refers to non-toxic salts of the compounds of this invention which are generally prepared by reacting the free base with a suitable organic or inorganic acid. Representative salts include the hydrochloride, hydroiodic, hydrobromide, sulfate, bisulfate, acetate, oxalate, valerate, oleate, palmitate, stearate, laurate, borate, benzoate, lactate, phosphate, tosylate, citrate, maleate, fumarate, succinate, tartrate, napsylate, clavulanate, methaneperoxoate and the like salts.
Compounds of the invention can be prepared readily according to the following reaction scheme or modifications thereof using readily available starting materials, reagents and conventional synthesis procedures. In these reactions, it is also possible to make use of variants which are in themselves known, but are not mentioned in greater detail. R 1 , R 2 , R 3 and ##STR3## are as defined above. Y is any suitable leaving group, such as halogen, mesylate or tosylate. COZ represents a suitable acylating agent such as a carboxylic acid chloride, a carboxylic acid activated as the mixed anydride, or the carboxylic ester activated by alkylaluminum reagents. ##STR4##
Reduction of 4-acetamidopyridine Formula II affords 4-acetamido-piperidine Formula III. A method for the preparation of 4-acetamidopiperidine III involves the reduction of 4-acylamino N-benzyl pyridinium compounds by alkali metal hydrides or catalytic hydrogenation of the aromatic ring with debenzylation as described in U.K. 1,537,867 (G. O. Weston) and U.K. 1,345,872 (J. L. Archibald and J. F. Cavalla) the disclosures of which are incorporated herein by reference. Preferred reduction conditions employ a ruthenium on carbon catalyst in a solvent such as alcohol, tetra hydrofuran, (THF), or acetic acid under an atmosphere of hydrogen. Subsequent reductive alkylation of the piperidine Formula III with aldehydes Formula IV provides the N-alkylated intermediates Formula V. Preferred conditions employ Pt/C catalyst in an inert solvent such as alcohol, THF, or acetic acid under an atmosphere of hydrogen. Alternative preferred conditions employ borane-pyridine complex as the reducing agent at room temperature in alcohol, acetic acid or methylene chloride. Hydrolysis of the amide bond of acetamides Formula V provides amine intermediates Formula VI. Although hydrolysis may be effected in acid or base, the preferred method employs hydrolysis in 1.2 M HCl at 100° C. Alternative preferred acylating conditions leading to amides I (R 2 =lone pair) employ COZ, which can be a carboxylic acid chloride, a carboxylic acid activated as the mixed anhydride, or the carboxylic ester activated by alkylaluminum reagents.
The intermediates Formula I are subsequently converted to the quaternary salts Formula I (where R 2 is not an unshared valence bond) by N-alkylating reagents R 2 X Formula VIII (where X is a suitable leaving group such as halogen, mesylate, or tosylate) in an inert solvent. Preferred alkylation conditions employ acetonitrile as the solvent at room temperature.
The compounds of the present invention can be administered in such oral dosage forms as tablets, capsules, pills, powders, granules, elixers, tinctures, suspensions, syrups and emulsions. Likewise, it can also be administered in intravenous, intraperitoneal, subcutaneous or intramuscular form, all using forms known to those of ordinary skill in the pharmaceutical arts. In general, the preferred form of administration is oral. An effective but non-toxic amount of the compound is employed in the treatment of arrhythmias of the heart. The dosage regimen utilizing the compound of the present invention is selected in accordance with a variety of factors including the type, species, age, weight, sex and medical condition of the patient; with the severity of the condition to be treated; the route of administration; the renal and hepatic function of the patient; and the particular compound employed or salt thereof. An ordinarily skilled veterinarian or physician can readily determine and prescribe the effective amount of the drug required to prevent, treat or arrest the progress of the condition.
Oral dosages of the compounds of the present invention, when used for the indicated cardiac effects, will range between about 0.1 mg per kilogram of body weight per day (mg/kg/day) to about 1000 mg/kg/day and preferably 1.0 to 100 mg/kg/day. Advantageously, the compounds of the present invention can be administered in a single daily dose or the total daily dosage can be administered in divided doses of two, three or four times daily.
In the pharmaceutical compositions and methods of the present invention, the compounds described in detail below will form the active ingredient that will typically be administered in admixture with suitable pharmaceutical diluents, excipients or carriers (collectively referred to herein as "carrier" materials) suitably selected with respect to the intended form of administration, that is, oral tablets, capsules, elixers, syrups and the like, and consistent with conventional pharmaceutical practices.
For instance, for oral administration in the form of tablets or capsules, the active drug component can be combined with an oral non-toxic pharmaceutically acceptable inert carrier such as lactose, starch, sucrose, glucose, methylcellulose, magnesium stearate, dicalcium phosphate, calcium sulfate, mannitol, sorbitol and the like; for oral administration in liquid form, the active drug components can be combined with any oral non-toxic pharmaceutically acceptable inert carrier such as ethanol, glycerol, water, and the like. In the case of oral administration and in liquid form, suitable flavoring carriers can be added such as cherry syrup and the like. Moreover, when desired or necessary, suitable binders, lubricants, disintegrating agents and coloring agents can also be incorporated into the mixture. Suitable binders include starch, gelatin, natural sugars such as glucose or beta-lactose, corn sweeteners, natural and synthetic gums such as acacia, tragacanth, or sodium alginate, carboxymethylcellulose, polyethylene glycol and various waxes. Lubricants for use in these dosage forms include magnesium stearate, sodium benzoate, sodium acetate, sodium stearate, sodium chloride, sodium oleate and the like. Disintegrators include, without limitation, starch, methylcellulose, agar, bentonite, xanthan gum and the like.
The compounds of this invention can also be administered by intravenous route in doses ranging from 0.01 to 10 mg/kg/day.
Furthermore, it is also contemplated that the invention can be administered in an intranasal form topically via the use of suitable intranasal vehicles, or via transdermal routes, using those forms of transdermal skin patches well known to those of ordinary skill in that art. In the case of transdermal skin patch administration, daily dosage is continuous via the transdermal delivery system rather than divided, as in an oral delivery system.
The compounds of this invention exhibit antiarrythmic activity useful in the treatment of various cardiac arrhythmias. The test procedures employed to measure this activity of the compounds of the present invention are described below.
EXAMPLE 1
Guinea pigs, of either sex weighing between 200-350 g, are acutely sacrificed and the right ventricular papillary muscle is isolated. A sample of a given test compound is added using an in vitro tissue bath. Concentrations used are generally 3×10 -5 M, but may also be as low as 3×10 -7 M. Changes in refractory period are measured before and after adding 1 concentration (usually 3×10 -5 M, as noted above) of a test compound to the bath. One hour is allowed for drug equilibration. A compound is considered active (Class III) if an increase in ventricular refractory period is 25 msec or more (at 3×10 -5 M).
______________________________________ ResultsCompound Concentration (M) Change (msec)______________________________________H.sub.2 O -- 8Disopyramide 3 × 10.sup.-5 20Clofinium 3 × 10.sup.-5 24Sotalol 3 × 10.sup.-5 35Example 9 3 × 10.sup.-5 55Example 10 3 × 10.sup.-5 50Example 11 3 × 10.sup.-5 30Example 12 1 × 10.sup.-6 20Example 13 3 × 10.sup.-5 40Example 14 1 × 10.sup.-6 15Example 15 3 × 10.sup.-5 40Example 16 1 × 10.sup.-6 30Example 17 3 × 10.sup.-5 30Example 18 3 × 10.sup.-5 55Example 19 1 × 10.sup.-6 25Example 20 1 × 10.sup.-6 40Example 21 3 × 10.sup.-5 190Example 22 3 × 10.sup.-5 95Example 23 3 × 10.sup.-5 35Example 24 3 × 10.sup.-5 60Example 25 3 × 10.sup. -5 60Example 26 3 × 10.sup.-5 90Example 29 3 × 10.sup.-6 60Example 87 3 × 10.sup.-6 55Example 30 3 × 10.sup.-6 80Example 36 3 × 10.sup.-6 55Example 37 3 × 10.sup.-5 35Example 39 3 × 10.sup.-5 155Example 40 3 × 10.sup.-5 125Example 41 3 × 10.sup.-6 70Example 42 3 × 10.sup.-6 60Example 44 3 × 10.sup.-6 40Example 46 3 × 10.sup.-6 95Example 51 3 × 10.sup.-6 75Example 53 3 × 10.sup.-6 50Example 58 3 × 10.sup.-6 60Example 59 3 × 10.sup.-6 35Example 60 3 × 10.sup.-6 25Example 64 3 × 10.sup.-5 85Example 66 3 × 10.sup.-5 45Example 69 3 × 10.sup.-5 25Example 70 3 × 10.sup.-5 40Example 72 3 × 10.sup. -5 50Example 75 3 × 10.sup.-5 60Example 77 1 × 10.sup.-6 60Example 78 3 × 10.sup.-6 50Example 80 3 × 10.sup.-5 115Example 82 3 × 10.sup.-6 55______________________________________
The preferred compounds of the invention are any or all of those specifically set forth below. The compounds are not, however, to be construed as forming the only genus that is considered as the invention and any combination of such compounds may itself form a genus or sub-genus. ##STR5##
The following non-limiting examples further illustrate details for the preparation of the compounds of the present invention. Those skilled in the art will readily understand that known variations of the conditions and processes of the following preparative procedures can be used to prepare these compounds. All temperatures are degrees Celsius unless otherwise noted. Melting points were determined on a Thomas-Hoover Unimelt Capillary Apparatus and are not corrected. Unless otherwise noted, I.R. and NMR spectra were consistent with the assigned structure.
EXAMPLE 2 ##STR6##
Preparation of 4-acetamidopyridine acetate II
4-Aminopyridine (101.28 g) and acetic anhydride (110 g) were mixed neat and heated at 100° C. for 1/2 h. The solidified reaction mixture was triturated with acetone, filtered off, and washed with ether to afford 186.48 g of II as a white solid in two crops. Anal. calcd for C 9 H 12 N 2 O 3 : C, 55.09; H, 6.16; N, 14.26. Found: C, 55.04; H, 5.96; N, 15.22.
EXAMPLE 3 ##STR7##
Preparation of 4-acetamidopiperidine acetate III
A solution of the product of Example 2 (75 g) in 750 mL acetic acid was reduced over PtO 2 catalyst at 60 psi hydrogen atmosphere at 60° C. for 7 hours. The solution was filtered, concentrated and triturated with ether to afford the title compound quantitatively as a white solid which was used directly in subsequent reactions.
EXAMPLE 4 ##STR8##
Preparation of 1-(4-methoxyphenyl)methyl-4-acetamido-piperidine
A mixture of 10 g amine acetate from Example 3 and 13.48 g 4-methoxy benzaldehyde was hydrogenated in 100 mL ethanol over a Pt/C catalyst at room temperature for 3 hours. The reaction mixture was filtered and concentrated to give 74.0 g of the acetate salt of the title compound as a white solid which was hydrolyzed directly as described in Example 4. (An alternative reductive amination procedure is described in Example 5). Conversion of a sample to the free base using aqueous base and ethyl acetate extraction provided a white solid after solvent evaporation and trituration with ether: mp 140°-142° C.; Anal. calcd for C 15 H 22 N 2 O 2 : C, 68.67; H, 8.45; N, 10.68. Found: C, 65.26; H, 8.60; N, 10.77.
EXAMPLE 5 ##STR9##
Preparation of 1-(4-methoxyphenyl)methyl-4-amino piperidine
A) A solution of 50 g of the product of Example 4 was dissolved in 500 mL of 1.2N HCl and heated at 100° C. for 8 h. The solution was made alkaline with 50% aq. NaOH and extracted three times with ether. The combined organic layers were washed with water and saturated brine, dried over sodium sulfate, and concentrated to give the title compound as 28 g of clear oil which was used without further purification.
B) (Alternative general reductive alkylation procedure) A solution of 50 mmol amine acetate (product of Example 3) and 100 mmol of 4-methoxybenzaldehyde in 125 mL methylene chloride and 15 mL acetic acid was treated with 50 mmol of borane-pyridine complex and allowed to stir at room temperature overnight. The removal of volatiles by rotary evaporation afforded the acetamide of Example 4 as an oil which was dissolved in 300 mL of 1.2N HCl and heated overnight on a steam bath. The cooled reaction mixture was extracted once with a 50 mL portion of ethyl acetate which was discarded. The aqueous layer was made basic with aq. NaOH and extracted three times with 50 mL ether. The combined layers were washed with water and dried over sodium sulfate. Solvent removal afforded the title compound as a crude oil (yield typically 60-70% for two steps) which was used directly without further purification.
EXAMPLE 6
General acylation procedures
A) 10 mmol of the amine of Example 5 is dissolved in a mixture of 25 mL chloroform and 11 mmol of triethylamine cooled to 0° C. A solution of 11 mmol of the acyl chloride neat or dissolved in 25 mL chloroform is added dropwise and the reaction mixture is allowed to stir for 1 h. Volatiles are removed in vacuo and the residue is partitioned between dilute aqueous base and ethyl acetate. Drying of the ethyl acetate extract and evaporation leads to the crude product which is optionally purified by flash chromatography on silica gel using 92.5:7:0.5 chloroform:ethanol:ammonium hydroxide and crystallized from ethyl acetate/hexane or converted to the HCl salt using dioxane/HCl followed by recrystallization from methanol/ether.
B) A stirred solution of 10 mmol acylating acid in 25 mL chloroform is treated with 10 mmol of triethylamine followed by 10 mmol of isobutyl chloroformate. After 10 minutes at ambient temperature the amine of Example 5 was added and the reaction is allowed to stir for 1/2 h. The reaction mixture is washed with 10% NaOH solution and the organic layer is dried and evaporated to give a residue which is optionally purified by flash chromatography on silica gel using 92.5:7:0.5 chloroform:ethanol:ammonium hydroxide recrystallized from ethyl acetate converted to the HCl salt using dioxane/HCl followed by recrystallization from methanol/ether.
EXAMPLE 7
Preparation of quaternary salt
A solution of 200 mg of the amide of Example 6 in 5 mL acetone was treated with 4 drops of iodomethane. The reaction mixture was stirred for 18 h and the white crystalline precipitate was filtered off to afford 206 mg of white solid which was recrystallized from acetonitrile to give 128 mg of quaternary iodide as fluffy white needles, mp 236°-237° C.
EXAMPLE 8
Preparation of N-oxide
A solution of 0.50 g of the amide of Example 6 in 10 mL CH 2 Cl 2 was treated with 300 mg of m-chloroperoxybenzoic acid at 0° C. After 1 h the solution was washed consecutively with 10 mL 1N NaOH, water, and sat'd. brine. The solution was dried over sodium sulfate and concentrated to afford 0.51 g of white solid which was recrystallized from CH 2 Cl 2 /ethyl acetate to give 0.33 g of an N-oxide as a white powder, mp 200.5°-202.5° C.
EXAMPLE 9 THROUGH 89
Using the procedures of Examples 2 through 8 and making the appropriate substitutions at positions R 1 , R 2 , R 3 , and X, the following products were obtained as presented in Table I, below. Table I specifies the moiety at R 1 , R 2 , R 3 and ##STR10## the number of methylenes represented by n, the compound's melting point range in degrees Celsius (where available) and the compound's elemental analysis. ##STR11## All piperidinyls are 4-piperidinyl unless otherwise noted.
Example R.sup.1 R.sup.2 R.sup.3 X n mp, deg. C. Analysis 9 ##STR12## H ##STR13## 1 C.sub.18 H.sub.21 N.sub.3 O 10 ##STR14## H ##STR15## 1 C.sub.18 H.sub.21 N.sub.3 O 11 ##STR16## H ##STR17## 1 C.sub.18 H.sub.21 N.sub.3 O 12 ##STR18## H ##STR19## 1 C.sub.26 H.sub.33 ClN.sub.2 O.sub.2 13 ##STR20## H ##STR21## 1 155-157 C.sub.19 H.sub.28 N.sub.2 O 14 ##STR22## H ##STR23## 1 168-169.5 C.sub.19 H.sub.23 N.sub.3 O 15 ##STR24## H ##STR25## 1 155.5-158 C.sub.17 H.sub.20 N.sub.2 O.sub.2 16 ##STR26## H ##STR27## 1 170-171 C.sub.20 H.sub.30 N.sub.2 O.sub.2 17 CH.sub.3 H ##STR28## 1 137-140 C.sub.15 H.sub.22 N.sub.2 O.sub.2 18 ##STR29## H ##STR30## 1 136-137 C.sub.18 H.sub.22 N.sub.2 O.sub.3 19 ##STR31## H ##STR32## 1 142-143 C.sub.23 H.sub.28 N.sub.2 O.sub.2 20 ##STR33## H ##STR34## 1 135-137 C.sub.22 H.sub. 26 N.sub.2 O.sub.2 21 ##STR35## H ##STR36## 1 136-138 C.sub.22 H.sub.24 N.sub.2 O.sub.3 22 ##STR37## H ##STR38## 1 C.sub.19 H.sub.23 N.sub.3 O.sub.2 23 ##STR39## H ##STR40## 1 161-162 C.sub.18 H.sub.22 N.sub.2 O.sub.2 S 24 ##STR41## H ##STR42## 1 200-202 C.sub.23 H.sub.24 N.sub.2 O.sub.4 25 ##STR43## H ##STR44## 1 210-211 C.sub.19 H.sub.24 N.sub.2 O.sub.2 26 ##STR45## H ##STR46## 1 134-137 C.sub.24 H.sub.32 N.sub.2 O.sub.4 27 CH.sub.3 H ##STR47## 2 162-164 C.sub.16 H.sub.24 N.sub.2 O.sub.2 28 ##STR48## H ##STR49## 1 178.5-179.5 C.sub.18 H.sub.22 N.sub.2 O.sub.2 29 ##STR50## H ##STR51## 1 140-141 C.sub.22 H.sub.24 N.sub.2 O.sub.3 30 ##STR52## H ##STR53## 1 135-137 C.sub.23 H.sub.28 N.sub. 2 O.sub.2 31 ##STR54## H ##STR55## 1 156-158 C.sub.24 H.sub.30 N.sub.2 O.sub.2 32 ##STR56## H ##STR57## 1 122-124 C.sub.20 H.sub.26 N.sub.2 O.sub.3 33 ##STR58## H ##STR59## 1 132-134 C.sub.24 H.sub.28 N.sub.2 O.sub.3 34 ##STR60## H ##STR61## 1 148-149 C.sub.22 H.sub.23 ClN.sub.2 O.sub.3 35 ##STR62## H ##STR63## 1 156-158 C.sub.23 H.sub. 26 N.sub.2 O.sub.2 36 ##STR64## H ##STR65## 1 140-142 C.sub.23 H.sub.26 N.sub.2 O.sub.4.HCl 37 ##STR66## H ##STR67## 1 147-148 C.sub.24 H.sub.28 N.sub.2 O.sub.5 38 ##STR68## H ##STR69## 1 126-128 C.sub.22 H.sub.23 ClN.sub.2 O.sub.3 39 ##STR70## H ##STR71## 1 158-160 C.sub.22 H.sub.24 N.sub.2 O.sub.2 S 40 ##STR72## H ##STR73## 1 270-272 C.sub.23 H.sub.24 N.sub.2 O.sub.4.HCl 41 ##STR74## H ##STR75## 1 oil C.sub.22 H.sub.25 N.sub.2 O.sub.2.HCl 42 ##STR76## H ##STR77## 1 146-148 C.sub.23 H.sub.28 N.sub.2 O.sub.3 43 ##STR78## H ##STR79## 1 147-149 C.sub.23 H.sub.28 N.sub.2 O.sub.3 44 ##STR80## H ##STR81## 1 145-147 C.sub.20 H.sub.25 N.sub.3 O.sub.2 45 ##STR82## H ##STR83## 1 150-152 C.sub.21 H.sub.25 N.sub.3 O.sub.2 46 ##STR84## H ##STR85## 1 142-144 C.sub.23 H.sub.26 N.sub.2 O.sub.3 47 ##STR86## H ##STR87## 1 131-133 C.sub.22 H.sub.28 N.sub.2 O.sub.2 48 ##STR88## H ##STR89## 1 141-143 C.sub.23 H.sub.28 N.sub.2 O.sub.2 49 ##STR90## H ##STR91## 1 125-127 C.sub.23 H.sub.30 N.sub.2 O.sub.2.HCl 50 ##STR92## H ##STR93## 1 92-96 C.sub.23 H.sub.28 N.sub.2 O.sub.2.HCl 51 ##STR94## H ##STR95## 1 134.5-135 C.sub.22 H.sub.26 N.sub.2 O.sub.3 52 ##STR96## H ##STR97## 1 C.sub.21 H.sub.26 N.sub.2 O.sub.2 53 ##STR98## H ##STR99## 1 190-192 C.sub.22 H.sub.23 N.sub.3 O.sub.5 54 ##STR100## H ##STR101## 1 197-199 C.sub.22 H.sub.25 N.sub.3 O.sub.4 55 ##STR102## H ##STR103## 1 C.sub.17 H.sub.24 N.sub. 2 O.sub.2 56 ##STR104## H ##STR105## 1 210-212 C.sub.22 H.sub.24 Cl.sub.2 N.sub.2 O.sub.2 57 ##STR106## H ##STR107## 1 142-143 C.sub.24 H.sub.30 N.sub.2 O.sub.2 58 ##STR108## H ##STR109## 1 133-135 C.sub.18 H.sub.21 BrN.sub.2 O.sub.3 59 ##STR110## H ##STR111## 1 155-157 C.sub.21 H.sub.22 N.sub.2 O.sub.3 60 ##STR112## H ##STR113## 1 215-218 C.sub.23 H.sub.29 N.sub.3 O.sub.4 S 61 CH.sub.3 H ##STR114## 1 143-144 C.sub.14 H.sub.19 N.sub.3 O.sub.3 62 ##STR115## H ##STR116## 1 155-157 C.sub.21 H.sub.21 N.sub.3 O.sub.4 63 CH.sub.3 H ##STR117## 1 162-164 C.sub.14 H.sub.19 ClN.sub.2 O 64 ##STR118## H ##STR119## 1 137-139 C.sub.21 H.sub.21 ClN.sub.2 O.sub.2 65 ##STR120## H ##STR121## 1 157-159 C.sub.24 H.sub.30 N.sub.2 O.sub.2 66 ##STR122## CH.sub.3 H ##STR123## 1 236-237 C.sub.23 H.sub.26 N.sub. 2 O.sub.3.Hl 67 ##STR124## H ##STR125## 1 184-185.5 C.sub.21 H.sub.28 N.sub.2 O.sub.2 68 CH.sub.3 H ##STR126## 1 163-164.5 C.sub.13 H.sub.19 N.sub.3 O 69 CH.sub.3 H ##STR127## 1 103-105 C.sub.15 H.sub.22 N.sub.2 O.sub.2 70 ##STR128## H ##STR129## 1 114-115 C.sub.22 H.sub.24 N.sub.2 O.sub.3 71 CH.sub.3 H ##STR130## 1 C.sub.15 H.sub.22 N.sub.2 O.sub.2 72 ##STR131## O H ##STR132## 1 200.5-202.5 C.sub.22 H.sub.24 N.sub.2 O.sub.4 73 ##STR133## H H 1 C.sub.15 H.sub.18 N.sub.2 O.sub.2 74 CH.sub.3 H ##STR134## 1 145-147 C.sub.16 H.sub.23 N.sub.3 O.sub.2.CHOOOH 75 ##STR135## H ##STR136## 1 230-232 C.sub.23 H.sub.25 N.sub.3 O.sub.3 76 ##STR137## H ##STR138## 1 C.sub.22 H.sub.25 ClN.sub.2 O.sub.3 77 ##STR139## H ##STR140## 1 C.sub.23 H.sub.26 N.sub.2 O.sub.4 78 ##STR141## H ##STR142## 1 C.sub.23 H.sub.27 N.sub.3 O.sub.2.2(HCl) 79 ##STR143## H ##STR144## 1 189-190 C.sub.22 H.sub.23 N.sub.3 O.sub.5 80 ##STR145## H ##STR146## 1 98-100 C.sub.22 H.sub.27 N.sub.3 O.sub.3.2(HCl) 81 CH.sub.3 H ##STR147## 1(substituted byCO.sub.2 CH.sub.2 CH.sub.3) C.sub.17 H.sub.24 N.sub.2 O.sub.3 82 ##STR148## CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3 ##STR149## 1 C.sub.26 H.sub.31 ClN.sub.2 O.sub.5 83 ##STR150## CH.sub.2 CO.sub.2 H ##STR151## 1 C.sub.24 H.sub.26 N.sub.2 O.sub.5 84 ##STR152## H ##STR153## 1 152-153 C.sub.24 H.sub.30 N.sub.2 O.sub.2 85 ##STR154## H ##STR155## 1 198-200 C.sub.21 H.sub.22 N.sub.2 O.sub.3 86 CH.sub.3 H ##STR156## 1 C.sub.12 H.sub.18 N.sub.2 O.sub.2 87 ##STR157## H ##STR158## 1 C.sub.23 H.sub.28 N.sub.2 O.sub.2 88 ##STR159## H ##STR160## 1 C.sub.20 H.sub.22 N.sub. 2 OF.sub.3 89 ##STR161## H ##STR162## 1 C.sub.21 H.sub.27 N.sub.2 O.sub.3
While the invention has been described and illustrated with reference to certain preparative embodiments thereof, those skilled in the art will appreciate that various changes, modifications and substitutions can be made therein without departing from the spirit and scope of the invention. For example, effective dosages other than the preferred range as set forth herein above may be applicable as a consequence of variations in the responsiveness of the mammal being treated for severity of cardiac arrhythmia, dosage-related adverse effects, if any, and analogous considerations. Likewise, the specific pharmacological responses observed may vary according to and depending upon the particular active compounds selected or whether there are present certain pharmaceutical carriers, as well as the type of formulation and mode of administration employed, and such expected variations for differences in the results are contemplated in accordance with the objects and practices of the present invention. It is intended, therefore, that the invention be limited only by the scope of the claims which follow, and that such claims be interpreted as broadly as is reasonable. | Substituted N-benzylpiperidine amides, which have activity as Class III antiarrhythmic agents, acting by prolonging cardiac action potential repolarization. The invention further provides for compositions incorporating the compunds and methods of their use, as well as providing for pharmaceutically acceptable salts of the compounds. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of application Ser. No. 13/484,679, filed May 31, 2012, which is a divisional of application Ser. No. 11/537,083, filed Sep. 29, 2006, the disclosures of which are hereby incorporated by reference in their entirety herein.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The invention relates to energy conversion systems for vehicles.
[0004] 2. Background Discussion
[0005] Direct current to direct current (DC/DC) buck, boost, or bi-directional converters may transfer energy between an energy source, or storage unit, e.g., a high-voltage battery, via a first port at a first voltage and an electric device, e.g., motor drive, via a second port at a second voltage higher than the first voltage.
[0006] A vehicle system may require energy to be transferred between several energy storage units and electric devices at differing voltages. Several DC/DC converters may be necessary to facilitate such energy transfer.
[0007] An energy conversion system is desired that can facilitate the transfer of energy between one or more energy storage units and one or more electric devices at differing voltages.
SUMMARY
[0008] In at least one embodiment, the invention takes the form of an energy conversion system for a vehicle. The system includes an energy source, or storage unit, an electric device, and an energy conversion arrangement. The arrangement transfers energy between the energy storage unit and the electric device via a first port and a second port. The arrangement also at least one of receives and provides energy via a third port.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 shows an energy conversion system in accordance with an embodiment of the invention.
[0010] FIG. 2 shows an energy conversion arrangement in accordance with an embodiment of the invention.
[0011] FIG. 3 shows an energy conversion arrangement in accordance with an embodiment of the invention.
[0012] FIG. 4 shows a transformer in accordance with an embodiment of the invention.
[0013] FIG. 5 shows a transformer in accordance with an embodiment of the invention.
[0014] FIG. 6 shows a transformer in accordance with an embodiment of the invention.
[0015] FIGS. 7 a - 7 d show circuits in accordance with embodiments of the invention.
[0016] FIG. 8 shows an energy conversion arrangement in accordance with an embodiment of the invention.
[0017] FIG. 9 shows an energy conversion arrangement in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
[0018] FIG. 1 shows energy conversion system 10 for vehicle 12 . System 10 includes energy sources, or storage units, 14 , 15 , energy conversion arrangement 16 , and electric devices 18 , 19 . Arrangement 16 is electrically connected with units 14 , 15 and devices 18 , 19 . Arrangement 16 may receive energy from or provide energy to units 14 , 15 , as will be explained in detail below. Arrangement 16 may also receive energy from or provide energy to devices 18 , 19 , as will be explained in detail below.
[0019] FIG. 2 shows an embodiment of arrangement 16 . In this embodiment, arrangement 16 receives energy from unit 14 and provides energy to device 18 and acts, inter alia, as a DC/DC boost converter.
[0020] Arrangement 16 includes capacitors 20 , 22 , switch 24 , diode 26 , and transformer 28 as shown in FIG. 2 . Switch 24 is an insulated gate bipolar transistor (IGBT). Switch 24 , however, may be implemented in any suitable fashion, such as with field effect transistors (FETs). Transformer 28 may be an isolated transformer or a non-isolated transformer, as will be explained in detail below.
[0021] Arrangement 16 also includes terminals 30 , 31 , 32 . Terminal 31 is common relative to terminal 30 and terminal 32 . Unit 14 , capacitor 20 , and transformer 28 are electrically connected with terminal 30 . Unit 14 and capacitor 20 are also electrically connected with terminal 31 . Terminal 30 and terminal 31 are a port. Device 18 is electrically connected with terminal 31 and terminal 32 . Terminal 31 and terminal 32 are a port. The voltage, Vy, at terminal 32 relative to terminal 31 is greater than the voltage, Vx, at terminal 30 relative to terminal 31 . Arrangement 16 further includes node 33 .
[0022] Arrangement 16 passes current between terminal 30 and terminal 32 in a manner typical of DC/DC boost converters through the selective opening and closing of switch 24 , e.g., pulse width modulation. When switch 24 is conducting, the current through transformer 28 increases thereby increasing the energy stored in transformer 28 . When switch 24 is not conducting, the energy stored in transformer 28 forces diode 26 to conduct thereby delivering current to terminal 32 .
[0023] Arrangement 16 also includes one or more terminals 36 , i.e., 36 a - 36 n. Terminals 36 a - 36 n are electrically connected to transformer 28 , as will be explained in detail below. Terminal 36 a may be electrically connected with unit 15 . Terminal 36 b may be electrically connected with device 19 . If transformer 28 is a non-isolated transformer, unit 15 and device 19 may share a common reference terminal, e.g., terminal 31 . Terminal 31 and any of terminals 36 a - 36 n may be a port. If transformer 28 is an isolated transformer, unit 15 and device 19 may or may not share a common reference terminal. Preferably, unit 15 and device 19 would not share a common reference terminal if transformer 28 is an isolated transformer. Any two of terminals 36 a - 36 n may be a port.
[0024] FIG. 3 shows an embodiment of arrangement 16 . In this embodiment, arrangement 16 receives energy from device 18 and provides energy to unit 14 and acts, inter alia, as a DC/DC buck converter.
[0025] Arrangement 16 includes capacitors 20 , 22 , switch 24 , diode 26 , and transformer 28 . Switch 24 is an IGBT. Switch 24 , however, may be implemented in any suitable fashion, such as with FETs. Transformer 28 may be an isolated transformer or a non-isolated transformer as explained above. Arrangement 16 also includes terminals 30 , 31 , 32 . Terminal 31 is common relative to terminal 30 and terminal 32 . Unit 14 , capacitor 20 , and transformer 28 are electrically connected with terminal 30 . Unit 14 and capacitor 20 are also electrically connected with terminal 31 . Device 18 is electrically connected with terminal 31 and terminal 32 . The voltage, Vy, at terminal 32 relative to terminal 31 is greater than the voltage, Vx, at terminal 30 relative to terminal 31 . Arrangement 16 further includes node 33 .
[0026] Arrangement 16 passes current between terminal 30 and terminal 32 in a manner typical of DC/DC buck converters through the selective opening and closing of switch 24 , e.g., pulse width modulation. When switch 24 is conducting, current flows from terminal 32 to terminal 30 . When switch 24 is not conducting, current flows from terminal 31 to terminal 30 .
[0027] Arrangement 16 also includes one or more terminals 36 , i.e., 36 a - 36 n. Terminals 36 are electrically connected to transformer 28 as will be explained in detail below. Terminal 36 a may be electrically connected with unit 15 . Terminal 36 b may be electrically connected with device 19 .
[0028] FIG. 4 shows an isolated version of transformer 28 . This isolated transformer 28 includes primary winding 38 and secondary winding 40 , both being wound around magnetic core 42 . The transformer 28 may have multiple mutually isolated secondary windings 40 . Terminals 36 a - 36 n have voltages with no offset. The amplitude of the voltage difference between terminals 36 a and 36 x is less than the amplitude of the voltage difference between terminals 36 a and 36 n. Current coming from any of terminals 36 a - 36 n may be rectified in any suitable fashion, such as with a full-wave rectifier or half-wave rectifier, as will be explained in detail below.
[0029] FIG. 5 shows a non-isolated version of transformer 28 . This non-isolated transformer 28 includes primary winding 44 wound around magnetic core 46 . Terminals 36 a - 36 n have voltages, with respect to terminal 31 or any other common reference terminal, with offset. Terminal 30 may be connected with any of terminals 36 a - 36 n. Node 33 may be connected with any of terminals 36 a - 36 n. Terminal 30 and node 33 , however, may not be connected to the same terminal. Current coming from any of terminals 36 a - 36 n may be rectified in any suitable fashion, such as with a full-wave rectifier or half-wave rectifier, as will be explained in detail below. This non-isolated transformer 28 may also include isolated secondary windings. Therefore, it may have non-isolated as well as isolated outputs.
[0030] FIG. 6 shows an isolated version of transformer 28 . Switches 48 , 50 , 52 , and 54 may be selectively opened or closed. If switch 54 is closed and switches 48 , 50 , and 52 are open, secondary winding 40 is isolated from primary winding 38 . It provides power to a load with galvanic isolation with respect to the primary side. If secondary winding 40 is not used, it can be incorporated with primary winding 38 to increase the power rating or inductance. For example, if switches 48 , 50 , and 54 are closed and switch 52 is open, primary winding 38 and secondary winding 40 are connected in parallel, thus increasing the current rating of transformer 28 . If switches 50 and 52 are closed and switches 48 and 54 are open, primary winding 38 and secondary winding 40 are connected in series, thus increasing the inductance of transformer 28 . Switches 48 , 50 , 52 , and 54 may be implemented in any suitable fashion. In the embodiment of FIG. 6 , switches 48 , 50 , 52 , and 54 are relays.
[0031] FIG. 7 a shows rectifier circuit 56 that may be used with transformer 28 . Circuit 56 includes diodes 58 , 60 electrically connected, as shown, along with output terminals 62 , 64 . If the voltage at terminal 36 is greater than the voltage at terminal 62 , diode 58 will conduct. If the voltage at terminal 36 is less than the voltage at terminal 64 , diode 60 will conduct.
[0032] FIG. 7 b shows rectifier circuit 66 that may be used in conjunction with transformer 28 . Circuit 66 includes diodes 68 , 70 , 72 , and 74 electrically connected as shown. Circuit 66 also includes terminals 76 , 78 , 80 , and 82 . Terminal 76 and terminal 82 are a port. Terminal 78 and terminal 80 are another port. The ports do not share a common reference terminal and they deliver two output voltages with different amplitudes.
[0033] FIG. 7 c shows rectifier circuit 84 that may be used in conjunction with transformer 28 . Circuit 84 includes diodes 86 , 88 , 90 , and 92 electrically connected as shown. Circuit 84 also includes terminals 94 , 96 , and 98 . Terminal 94 and terminal 98 are a port. Terminal 96 and terminal 98 are another port. The ports share common negative-side reference terminal 98 . The outputs of the ports are of the same polarity but may have different output voltage amplitudes.
[0034] FIG. 7 d shows rectifier circuit 100 that may be used in conjunction with transformer 28 . Circuit 100 includes diodes 102 , 104 , 106 , and 108 electrically connected as shown. Circuit 100 also includes terminals 110 , 114 , and 116 . Terminal 114 and terminal 110 are a port. Terminal 116 and terminal 110 are another port. The ports share common positive-side reference terminal 110 . The outputs of the ports are of the same polarity but may have different output voltage amplitudes.
[0035] FIG. 8 shows an embodiment of arrangement 16 . This embodiment includes capacitors 118 , 120 , terminals 122 , 123 , 124 , node 126 , diodes 128 , 130 , active switches 132 , 134 , and non-isolated transformer 136 . In this configuration, arrangement 16 can act as either a buck or boost converter. If switch 132 is disabled, arrangement 16 acts, inter alia, as a boost converter. If switch 134 is disabled, arrangement 16 acts, inter alia, as a buck converter. The voltage at terminal 122 is less than the voltage at terminal 124 relative to terminal 123 .
[0036] Non-isolated transformer 136 includes terminals 138 , e.g., 138 a - 138 j. Terminals 140 , e.g., 140 a - 140 h, and terminals 142 , e.g., 142 a - 142 h, are also shown. Other embodiments may have more or less terminals. The diodes may or may not be included.
[0037] If arrangement 16 acts as a buck converter, i.e., switch 134 is disabled, the voltage at terminals 142 g - 142 h is less than the voltage at terminal 122 , the voltage at terminals 142 e - 142 f is less than the voltage at terminal 122 but greater than zero, and the voltage at terminals 142 a - 142 d is less than zero. Furthermore, the voltage at terminals 140 g - 140 h is greater than the voltage at terminal 122 , the voltage at terminals 140 e - 140 f is greater than the voltage at terminal 122 but less than the voltage at terminal 124 , and the voltage at terminals 140 a - 140 d is greater than the voltage at terminal 124 .
[0038] In this configuration, arrangement 16 can receive energy from unit 15 or device 19 if unit 15 or device 19 are suitably electrically connected with any of terminals 142 e - 142 h . Arrangement 16 can provide energy to unit 15 or device 19 if unit 15 or device 19 are suitably electrically connected to any of terminals 140 a - 140 h or 142 a - 142 d.
[0039] If arrangement 16 acts as a boost converter, i.e., switch 132 is disabled, the voltage at terminals 142 g - 142 h is less than the voltage at terminal 122 , the voltage at terminals 142 e - 142 f is less than the voltage at terminal 122 but greater than zero, and the voltage at terminals 142 a - 142 d is less than zero. Furthermore, the voltage at terminals 140 g - 140 h is greater than the voltage at terminal 122 , the voltage at terminals 140 e - 140 f is greater than the voltage at terminal 122 but less than the voltage at terminal 124 , and the voltage at terminals 140 a - 140 d is greater than the voltage at terminal 124 .
[0040] In this configuration, arrangement 16 can receive energy from unit 15 or device 19 if unit 15 or device 19 are suitably electrically connected with any of terminals 142 e - 142 h . Arrangement 16 can provide energy to unit 15 or device 19 if unit 15 or device 19 are suitably electrically connected to any of terminals 140 a - 140 h or 142 a - 142 d.
[0041] FIG. 9 shows an embodiment of arrangement 16 . This embodiment includes capacitors 118 , 120 , terminals 122 , 123 , 124 , node 126 , diodes 128 , 130 , active switches 132 , 134 , and isolated transformer 144 . In this configuration, arrangement 16 can act as either a buck or boost converter. If switch 132 is disabled, arrangement 16 acts, inter alia, as a boost converter. If switch 134 is disabled, arrangement 16 acts, inter alia, as a buck converter. The voltage at terminal 122 is less than the voltage at terminal 124 relative to terminal 123 .
[0042] Isolated transformer 144 includes terminals 146 , e.g., 146 a - 146 j. Terminals 148 , e.g., 148 a - 148 j, and terminals 150 , e.g., 150 a - 150 j, are also shown. Other embodiments may have more or less terminals. The diodes may or may not be included. The diodes may also be shorted.
[0043] In this configuration, arrangement 16 can provide energy to unit 15 or device 19 if unit 15 or device 19 are suitably electrically connected to any of terminals 150 a - 150 j or 148 a - 148 j.
[0044] While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. | An energy conversion system transfers energy between an energy source, or storage unit, and an electric device via a first port and a second port and at least one of receives and provides energy via a third port. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a tear substitute for the external treatment of the eye.
2. Prior Art
Tear substitutes are used in the treatment of diseases of the eye, such as common keratoconjunctivitis sicca (so-called “dry eye”). Dry eye can be the result of different causes. The most frequent causes include reduction in tear production in the elderly, rheumatic or internal diseases (such as polyarthritis, diabetes and thyroid disease), diseases in which antibodies are raised against the body's own physiological substances (Sjörgren's disease, Lupus erythematodes, sclerodermia), skin diseases, hormonal changes, neuroparalysis (such as after a stroke, defective position of the eyelid, decortication of tear glands), ingestion of certain drugs (such as β blockers, birth control pill, soporifics and tranquilizers), nutritional deficiency, climatic influences (heat, dry environmental air, season, air conditioners), environmental pollution (ozone, dust, solvent vapors, etc.), working in front of monitors, and chronic use of vessel contracting eyedrops (so-called whiteners). Furthermore, such eye diseases are also caused, but less frequently, by autoimmune diseases, diseases of the hematopoietic system, local eye diseases such as inflammation and trauma of the tear glands or hereditary diseases. The resulting dysfunctions impair or prevent the formation of a normal tear film, which has an exceedingly complicated structure in its natural form. There are essentially three components which participate in the formation of the tear film:
An internal mucin layer which covers the epithelial surface, followed by a middle aqueous layer, and a thin, external lipid layer. The mucin layer here functions as an adhesive component for the wetting of the cornea. The aqueous component moisturizes the cornea and it has a cleaning and protective function. The lipid component prevents evaporation of the aqueous component and prevents a quick runoff of the tear film.
Only an intact tear film can guarantee the full functionality of the eye surface over time, and, in addition to the mentioned defects, properties which reduce abrasion, antibacterial properties, and the oxygen supply of the cornea can be of importance. The above-mentioned components of tears are continuously produced. The formation of a thin tear film over the cornea occurs spontaneously with each blink of the eyelid, as, during the downward movement of the upper lid, the external lipid layer of the tear film is compressed between the lid margins, where the aqueous layer essentially remains in its position. As soon as a part of the production of the tear components is interrupted or disturbed, or there is a mechanical obstacle to the formation of the tear film as a result of the blinking of the eyelid, corresponding complaints arise from, for instance the so-called sand grain effect to massive visual disorders, which in extreme cases, can lead to blindness as a result of irreversible damage to the cornea.
As there are a multitude of possible causes of “dry eye” and as the problem of the tear film [formation] is complex, a multitude of treatment agents are known from the state of the art. In this context, examples are the patents EP 698 388, DE 195 11 322, DE 43 03 818, EP 801 948, WO 97/45102, and WO 96/33695.
In the above-mentioned patents, descriptions are essentially provided of treatment agents which, as a result of introduction into the conjunctival sac, replace one or more missing components of natural tear film. The replacement is here carried out using substances which, having an appropriate retention time, take over the protective and abrasion-reducing functions, and possess the same or at least similar properties as the components to be substituted. The treatment agent which is commercially available under the trade name “Liposic,” for example, constitutes an attempt to duplicate all the natural tear components in a so-called three-dimensional tear.
The liquid treatment agents which are known from the state of the art, however, all present the drawback of having a relatively short residence time on the cornea. As a result, the treatment agent must be introduced at regular intervals into the eye, which can be very inconvenient and unpleasant for the patient. In the known gel form treatment agents, this drawback is at least partially avoided. However, in the case of gel form treatment agents, it was shown to be difficult to supply sufficient oxygen to the cornea.
In the patents EP 089 815 and EP 112 658, ophthalmological treatment agents for lubrication and protection of the eye surface are proposed which contain a perfluorocarbon or a substituted derivative thereof. The substantial advantages compared to conventional treatment agents that are mentioned are here the immiscibility with water and the high gas dissolution capacity, particularly for oxygen.
Because of the known high oxygen dissolution capacity of fluorocarbons, the treatment agent described in the above patents is said to guarantee a sufficient oxygen supply for the cornea. In addition, because of the high density of the perfluorocarbons, a long residence time on the cornea is said to be possible because the compounds are said to become enriched due to their high specific weight. Moreover, it is claimed that, because of the insolubility of the treatment agent in water, the use of preservatives could be omitted.
However, the drawbacks of these perfluorocarbon-containing treatment agents are that an intact mucin layer and sufficient secretion of lipids must be guaranteed to allow sufficient functionality of the agent on the cornea. Additional drawbacks result from impaired vision as a result of the formation of streaks, as well as the risk of obstructing the tear drainage ducts, caused by the immiscibility of the perfluorocarbons with water. Moreover, the immiscibility of perfluorocarbon and water, as well as the large interfacial tension between aqueous and perfluorocarbon-containing areas lead to the formation of diffusion barriers, which prevents a sufficient supply [of oxygen] to the cornea.
In addition, different forms of fluorogels are known from the state of the art, which were also proposed for medicinal applications. From U.S. Pat. No. 5,573,757 and EP 340 079 as well as WO 97/03644, polyaphron gels are known whose structure is stabilized by fluorinated surfactants. The structure and the properties of polyaphron gels are described, for example, in Chapter 8 of Foams and Biliquid Foams-Aphrons, F. Sebba, John Wiley, 1987.
Fluorogels as such, in general, present a pronounced viscoelasticity. These substances therefore are not suitable for an extraocular treatment of eye diseases, because the absence of a pronounced property of film formation does not allow an even distribution and wetting of the cornea.
Therefore, the problem of the present invention is to provide a tear substitute which is tolerated over the long term, which allows even wetting of the cornea, which presents a long retention time on the eye surface, and which guarantees the supply of oxygen and water-soluble nutrients to the cornea.
SUMMARY OF THE INVENTION
This problem is solved by using and/or applying to a person's or animal's eye a tear substitute for external treatment of the eye, characterized in that it contains at least one water-soluble fluorinated surfactant, water and a nonpolar component. In particular, the nonpolar component is a fluorocarbon or a silicone oil.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
There will now be described in detail the present invention and how the novel compositions of the present invention are formulated, and how they are used by applying to a person's or animal's eye. Essentially the tear substitute composition of the invention contains at least one water-soluble fluorinated surfactant, water and a nonpolar component. In particular, the nonpolar component is a fluorocarbon or a silicone oil. The fluorocarbon is chosen from the group comprising perfluoro compounds, partially fluorinated compounds having the general formula R F R H or R F R H R F , as well as, fluoro oligomers of the type (R F ) X R H , or a mixture thereof.
The tear substitute according to one aspect of the invention is characterized in that it is in the form of a gel and presents a polyaphron structure. The fluorinated surfactant is prepared according to the general formula:
R F —R pol
where R F represents a linear or branched perfluoroalkyl group having more than 5 carbon atoms and R pol represents a polar hydrocarbon residue which comprises at least one functional group chosen from the series:
CO—NH(R), CO—NH(R) 2 , COO—, COOR, SO 3 —, SO 2 —N(R) 2 , CH 2 —O—, R, PO 2 H, PO 3 H 2 , where R represents an alkyl.
The tear substitute according to the invention is characterized in that the molecular weight of the fluorinated surfactant is greater than 400 g/mol, and the surface tension of the fluorinated surfactant in an aqueous solution is less than 30 mNm. Further, according to the invention, the tear substitute is characterized in that the concentration of the fluorinated surfactant is less than critical micellar formation concentration, preferably less than 0.1%, and the concentration of the fluorocarbon is greater than 60 wt %, preferably greater than 90 wt %.
In a more specific aspect of the invention, the tear substitute is characterized in that the water-soluble fluorinated surfactant presents at least 6 completely fluorinated carbon atoms.
The tear substitute according to the invention is characterized in that it presents a refractive index of from 1.334 to 1.338.
As taught by the invention, the tear substitute is characterized in that the tear substitute on the cornea forms a thin film. The sum of the surface tension of the tear substitute and the interfacial tension between the tear substitute and the surface of the eye is smaller than the surface tension of the surface of the eye. When applied to an eye, the gel of tear substitute liquefies at least partially irreversibly under the effect of shearing stresses. It is preferred that the tear substitute be introduced into the conjunctival sac where the tear substitute forms a gel-form reservoir, a part of which liquefies during each blink of the eyelid. The liquefied portion of the tear substitute on the cornea forms a thin film.
One of the essential foundations of the present invention consists of the knowledge that a preparation which contains water, a nonpolar component and a water-soluble fluorinated surfactant, evenly wets smooth hydrophobic surfaces as soon as the preparation is in liquid form. The mechanism which effects the even distribution of the liquid preparation as a thin film on the smooth surface is the spreading of the immiscible components of the preparation according to the invention on top of each other, or on the hydrophilic or hydrophobic surface.
As a result, with the tear substitutes according to the invention, it is possible to achieve film formation from a water-containing preparation on the hydrophobic cornea. The formation of the thin film on the cornea here occurs as a result of blinking of the eyelid, as in natural tear formation. In this context, it is particularly the combination of hydrophilic, hydrophobic and fluorophilic properties, resulting from the structure of the fluorinated surfactants, which is used for the wetting of the cornea surface. By maintaining certain concentrations of the fluorinated surfactants it is possible, in addition, to adjust the surface and interfacial tensions of the components of the invention in such a manner that an optimal film formation and sufficient supply of oxygen to the cornea are possible.
The formation of thin films on the cornea surface leads to high residence capacities for the preparations and at the same time to the absence of prevention of tear secretion, mucus production and secretion of the marginal eyelid glands. Additionally, the resulting films prevent adhesion of the lid. In addition, the special surface properties of the preparation allow their passage, at the end of the residence time, into the natural tear drainage ducts without obstructing them. In this manner, the preparations according to the invention can take over the abrasion reducing and wetting functions of natural tear film without causing undesired side effects such as obstructed tear drainage ducts.
As a result of the combination of the components of the tear substitute according to the invention, it is possible to benefit from the advantages of the individual components without having to take into account any drawbacks.
The wetting properties of surfactants are well known, and they are used in many industrial processes. However, it is precisely these intrinsically advantageous properties which are the cause of their poor biocompatibility, which is reflected above all in dysfunctions in cell membranes. Therefore, the use of surfactant-containing substances in medical applications is strongly limited because of toxic behavior. Thus, for example, incompatibilities of oxygen-transporting emulsions can be explained by the effect of the surfactants which they contain. In particular, it appears that the use of surfactant-containing substances as tear substitutes is ruled out, because the function of the natural tear film is decisively effected by the surface-modifying properties of the lipids, and the latter react particularly sensitively to additives of other surfactant substances.
However, by the combination of the components of the tear substitute according to the invention, the surface active effect of the surfactants was, nevertheless, unexpectedly exploited, without impairment of the function of the surfactant compounds present in the natural tear film. The fluorinated surfactants used according to the invention, in this context, are characterized, in contrast to other known surfactants, by an improved biocompatibility. Fluorinated surfactants by themselves offer an improved biocompatibility, compared to nonfluorine-containing emulsifiers, combined with an unusual surface activity.
In addition, the damaging effects of the fluorinated surfactants in the preparations according to the invention are further repressed by the effects of the nonpolar components. This is achieved by the fixing of the fluorinated surfactants in the nonpolar matrix, resulting in a lowering of the surface tension of the aqueous components, without destroying the conditions which are caused by the natural surfactant compounds of the tear film. In this context, one exploits the fact that the interactions of the fluorinated surfactants with the nonpolar components are stronger than with the lipophilic components of the eye surface.
In this manner, the known surfactant properties of surfactants can be exploited for extraocular applications. In combination with the properties of water and the nonpolar matrix, the fluorinated surfactants provide the film-forming properties of the preparations according to the invention, and thus they allow an even thin-film wetting of the cornea.
As nonpolar components, fluorocarbons or silicone oil are particularly suited. If fluorocarbons are used as nonpolar components, the known advantageous properties of these substances, such as the high oxygen solubility and the lubricating and protecting function, can be exploited. As a result of the oxygen-transporting properties of the fluorocarbons, the cornea is sufficiently supplied with oxygen without impairing vision due to irregular layer thicknesses or milky emulsions, and without the formation of barrier layers between the hydrophobic cornea and the lipophobic fluorocarbons, which prevent oxygen transfer. In this context, it should be emphasized that fluorocarbon does not need a carrier (as, for example, in EP 089 815), rather it acts itself as a carrier for the fluorinated surfactants.
The formation of thin films as a result of the blinking of the eyelid and the spreading of the nonmiscible components not only leads to good gliding properties of the tear substitute according to the invention, in addition, because of the resulting fine distribution, it also is responsible for an increased residence duration on the surface. The latter effect is further supported by the fact that the thin film spontaneously seeks the lowest possible layer thicknesses, while the chosen surface and boundary properties at the same time act against rupturing of the films. By an appropriate selection of the components of the tear substitute, the surface tension of the tear substitute and the interfacial tension between the tear substitute and eye surface can be adjusted in such a manner that the sum of the two magnitudes is greater than the surface tension of the surface of the eye. This allows, in particular, improved film formation as a result of spreading on the eye surface. The film-like layer structures produced by spreading can take over the function of the natural tear film, where the cornea is wetted and protected without the need to hydrophilize the cornea surface.
The sliding properties and the residence duration can be further improved if the tear substitute according to the invention is first in the form of a polyaphron gel. It was found that such gels made of the components according to the invention decompose to the liquid condition as a result of the high shear stresses generated during blinking of the eyelid. This decomposition is irreversible as soon as the polyaphron structure is completely destroyed in the entire volume of the gel. It was shown that, as a result of shearing stresses, produced, for example, during the blinking of an eyelid, a certain volume of the gel is released as a result of irreversible liquefaction, and the liquefied portion of the gel is then evenly distributed on smooth surfaces due to spreading of the immiscible components, in the form of a thin film. Advantageously, the gel-form tear substitute is introduced into the conjunctival sac, where it forms a gel-form reservoir. During each blinking of the eyelid, a portion of the gel is liquefied and then it is finely and evenly distributed, in the form of a thin film, over the cornea surface.
With the described preparations according to the invention, the requirements for a tear substitute are successfully and excellently met. In this context, it should be mentioned, in particular, that although individual components intrinsically contribute important functions, it is only the combination of the individual components which allows the combination of the excellent properties of the fluorinated surfactants and the nonpolar components.
In this context, it is particularly the combination of the oxygen-transporting properties and the uptake capacity for water-soluble nutrients with the properties of high transparence and good film formation, which is of crucial importance. In addition to the replacement of functions such as wetting, reduction of abrasion, supply of nutrients and oxygen, additional properties of the preparations can also be used, such as the lipophobic properties of the preparations, leading to a reduction in the deposition of sebum, and the absence of sticking of the eyelid. An additional advantage results from the preservative properties of the nonpolar components of which not all the manufacturing steps must be carried out under sterile conditions. This means the preparations can be sterilized after the manufacture, for example, by treatment at 121° C. for 15 min in autoclaves, where the use of additional preservatives can be omitted.
The following examples should further explain the manufacture and the use of preparations according to the invention.
EXAMPLE 1
0.1 g Fluowet® (trade name, the company Clariant) OTL, 0.9 g water and 99 g perfluorophenanthrene (having a surface tension of σ=19 mNm) are homogenized, sterilized at 121° C. for 15 min, and then applied by means of syringe to a mirror and distributed, where the surface is wetted by an even, nonrupturing film.
EXAMPLE 2
Polyaphron gels are prepared by known methods from tetraethylpiperazinium salt of perfluorooctanoic acid (σ=15.9 mNm; 0.1 g), balanced salt solution (BSS); 0.9 g and perfluorophenanthrene (σ=19 mNm; 99 g) or perfluoroalkylethanol oxethylate (σ=19 mNm; 0.1 g) BSS (0.9 g) and perfluorophenanthrene (σ=19 mNm; 99 g), and sterilized at 121° C. for 15 min in the autoclave. The gel-form preparations were filled into syringes and investigated by a Draize test. No irritations occurred during the Draize test. Even two weeks after application of the gel, the tear secretion, mucus production or secretion of the lid margin glands in rabbits was not impaired. Even after continuation of daily treatment for 16 weeks, no signs of incompatibility were observed.
EXAMPLE 3
A preparation prepared according to Example 1 is applied to the eyes of rabbits. A short time after application, a known treatment agent for enlarging the pupils is applied. It was observed that the pupil-enlarging agent loses its effect as soon as a thin film of the tear substitute according to the invention has formed on the cornea. This observation serves as a demonstration of the capacity of the preparation according to the invention to form thin closed films over the cornea, as with the natural tear. In addition, this example shows that the preparations according to the invention have a protective function, by preventing water-containing or water-soluble substance from coming in contact with the eye surface as soon as a film has formed on the cornea.
EXAMPLE 4
From a 10% solution of perfluorooctanoic acid tetraethylpiperazinium salt (having surface tension σ=15.9 mNm) in water and highly purified silicone oil 1000 mPas, a gel is produced by foaming the aqueous solution and introduction of the silicone oil. After sterilization at 121° C. for 15 min, this preparation is applied to a water-loaded surface. Spontaneous spreading occurs. | A tear replacement solution that contains at least one water-soluble fluorosurfactant, water and a non-polar component, preferably in gel form, and a method for the external treatment for the eye of an mammal by applying the tear replacement solution to the eye, preferably by placing in the conjunctival sac. | 8 |
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an apparatus and a method for image processing, and more particularly, to an apparatus and a method for image processing with a cutting unit.
[0003] 2. Description of the Prior Art
[0004] Nowadays, most image processing depends on CPU operations. Image processing requires a huge amount of operations, and therefore is a heavy burden on a CPU whether in computer or in image player applications.
[0005] Please refer to FIG. 1 . FIG. 1 is a block diagram of a prior art image processing apparatus 100 . The conventional image processing apparatus 100 comprises a CPU 10 , a frame buffer 20 , a compressed file (CF) 30 , a random access memory (RAM) 50 , and a video encoder 40 .
[0006] Generally, the CPU 10 performs a decoding operation on the compressed file 30 after receiving the compressed file 30 . One example of a compressed file is a JPEG (Joint Photographic Experts Group) file. The CPU 10 decodes all compressed files and stores the files in the RAM 50 pixel by pixel.
[0007] In the prior art, image cutting is performed after decoding. For instance, according to the selected range of display, the CPU 10 sieves out the pixels corresponding to the selected range of display in the RAM 50 , and loads the pixels from the RAM 50 . Afterward, the CPU performs resizing and rotation operations on the pixels according to a user setting, and then stores the processed image data in the frame buffer 20 . Finally, the video encoder 40 encodes the processed image data stored in the frame buffer 20 and outputs to a computer display or a TV screen (not shown in FIG. 1 ).
[0008] However, every image processing operation (including decoding operations), needs to be performed by the CPU 10 alone. Especially when performing image cutting, the CPU 10 needs to process a huge amount of pixels. Therefore, these special image processing operations ordered by users bring a heavy burden to the CPU 10 , consequently it is likely that the display of the computer monitor or the TV screen will be adversely affected. These kinds of products will not be attractive to consumers.
SUMMARY OF INVENTION
[0009] It is therefore a primary objective of the claimed invention to provide an apparatus and a method for image processing.
[0010] Briefly described, the claimed invention discloses an apparatus and a method for image processing. An apparatus for image processing comprises an input First-In-First-Out buffer for receiving a compressed file, a decoding core for decoding the compressed file and outputting a decoded file as a plurality of code units, a cutting unit for selecting a portion of the code units corresponding to a specified range of display, a resizing unit for performing a rotation or a resizing operation on the portion of code units, a frame buffer for receiving a processed image data from the resizing unit and a digital video encoder for converting the processed image data into a digital video signal. Moreover, the method includes receiving a plurality of code units, and receiving a range of display information and choosing a portion of the plurality of code units according to the range of display information.
[0011] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0012] FIG. 1 is a block diagram of a prior art image processing apparatus.
[0013] FIG. 2 is a block diagram of the present invention image processing apparatus.
[0014] FIG. 3 is a diagram of a frame with all minimum code units (MCUs) within a frame.
DETAILED DESCRIPTION
[0015] The claimed invention introduces an apparatus for image processing. Please refer to FIG. 2 . FIG. 2 is a block diagram of the present invention image processing apparatus 220 adopted in a video player. The image processing apparatus 220 is an integrated chip including an input First-In-First-Out (FIFO) buffer 222 , a decoding core 223 , a cutting unit 225 , a resizing unit 226 , a frame buffer 224 , an output FIFO buffer 227 , and a digital video encoder 228 . According to the embodiment of the claimed invention, the decoding core 220 is a JPEG decoder, and the input compressed file is a JPEG file.
[0016] In the present invention, when a compressed file is input to a CPU, the CPU does not perform any operation but transmits the compressed file to the decoding core 220 directly. The input FIFO buffer 222 is utilized to temporarily store the compressed file. The decoding core 223 is utilized to decode the compressed file for transmitting the decoded file as minimum code units (MCUs), MCU by MCU to the cutting unit 225 . The cutting unit 225 is capable of selecting a specified range of display according to a user setting, and transmitting the MCUs corresponding to the specified range of display to the resizing unit 226 for performing a resizing operation or a rotation operation. The processed image data is stored in the frame buffer 224 . The digital video encoder 228 is capable of converting the image data stored in the frame buffer 224 into digital video signals and outputting them. Moreover, the output FIFO buffer 227 is utilized to receive the output image data of the cutting unit 225 and the resizing unit 226 , and outputting the processed image data back to the CPU by the command of the CPU.
[0017] Usually, the format and the parameters of the compressed file are stored in the sampling factor in the header of the JPEG file. When the JPEG file is input to the decoding core 223 , the decoding core 223 generates MCU data according to the sampling factor, and all the MCU data generated from the compressed file may form a frame. Please refer to FIG. 3 . FIG. 3 is a diagram of a frame 300 with all MCUs featured within it. Please also refer to FIG. 2 . The decoding core 223 outputs all MCUs in the frame 300 in order. Subsequently, the CPU outputs information about the selected range of display 310 to the cutting unit 225 . Therefore, the cutting unit 225 is capable of selecting MCU data corresponding to the selected range of display according to the information output by the CPU. For example, the selected range of display 310 in the frame 300 contains MCU 323 , MCU 324 , MCU 325 , MCU 326 , MCU 333 , MCU 334 , MCU 335 , and MCU 336 . Therefore, the cutting unit 225 is capable of performing cutting operations to the MCUs specified above. That is, the cutting unit 225 selects the range of display 310 only, and discards other MCUs beyond the range of display 310 . This way, unnecessary image processing operations are reduced. Following the discarding of out-of-range MCUs, the MCUs selected by the cutting unit 225 are input to the resizing unit 226 , and the resizing unit 226 may perform resizing operations or rotation operations or other special operations to the MCUs within the range of display 310 . The processed image data may be stored in the frame buffer 224 , and the digital video encoder 228 may read the image data stored in the frame buffer 224 , perform encoding, generate digital video signals and output the digital video signals to the image processing apparatus 220 . According to the embodiment of the claimed invention, the digital video encoder 228 is an ITU-R656 digital video encoder.
[0018] According to the present invention, when the JPEG file is input to the CPU, the CPU outputs the JPEG file to the decoding core and outputs a plurality of MCUs to the cutting unit 225 . The cutting unit 225 selects a specific number of MCUs and outputs the selected MCUs to the next stage, the resizing unit, for special processing.
[0019] The present invention integrates the cutting unit 225 into the image processing apparatus 220 . According to the pipelined cutting unit 225 in the image processing apparatus 220 , when a JPEG file is input, the decoded image of the JPEG file may be obtained after processing of each device, and the MCUs may be delivered to the cutting unit 225 for image cutting processing. Decoding and image cutting operations are no longer performed by the CPU alone. Therefore, for the CPU, the burden of image processing is reduced substantially. Hence, the display of the computer monitor or the TV screen is less likely to be adversely affected.
[0020] Furthermore, the cutting unit 225 performs operations on the decoded image file MCUs, MCU by MCU. The number of operations involved in the present invention method is much lower than the number of operations involved when performing operations pixel by pixel, as in the prior art. The speed of image processing is increased as well.
[0021] In summary, the advantage of the claimed invention is the reduction of the burden on the CPU, and the speeding up of image processing by utilizing a cutting unit.
[0022] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | The present invention discloses an apparatus and a method for image processing. According to the selected range by users, a cutting unit is added in the apparatus to trim the selected portion from an input image file. To reduce the CPU's loading and to increase the speed of image processing, design of the elements in the presented apparatus is a pipeline structure. In this way, images can be displayed smoothly on the screen. | 7 |
FIELD OF THE INVENTION
This invention relates to new methods for preparing polyquinazoline polymers and to the polymers themselves.
BACKGROUND OF THE INVENTION
Polyquinazoline polymers are useful in a broad range of electronics and microelectronics applications, including planarizing dielectric layers in integrated circuit manufacture, passivation layers, as protective coatings and potting compounds, as adhesives, as resins for printed wiring board fabrication, as dielectric materials, in coating applications for liquid crystal displays, flat panel television, solar windows, and the like, as fibers, and as high-strength films.
Methods of preparing polyquinazolines by condensation of nitriles with chloroimines are disclosed in U.S. Pat. No. 3,826,783 which issued to B. M. Bloch on Jul. 30, 1974. The polyquinazolines disclosed by Bloch are characterized by linkages at the 2 or 4 positions of the quinazoline which are either direct, or made through an arylene, alkylene, or alkarylene group.
Many classes of polyheterocycles containing ether linkages are known; the ether linkage providing processability, good thermal, mechanical, and electrical properties, and general ease of synthesis. However, polyquinazolines containing ether linkages at the quinazoline 2, or 4 position have not been reported.
It is desired to provide polyquinazolines having ether linkages at the quinazoline 2 or 4 position, derived from relatively low cost starting materials, which are processable and have good thermal, mechanical and electrical properties.
SUMMARY OF THE INVENTION
The present invention provides new and economical methods for forming polyquinazoline polymers and the polymers themselves.
In a preferred embodiment, the method for forming the polyquinazoline polymers of the present invention comprises treating a monomer comprising a quinazolone nucleus having one activated halide group with a base in a dipolar solvent to thereby form said polyquinazoline polymer.
In another embodiment, the method for forming the polyquinazoline polymers of the present invention comprises the steps of:
a) providing a bis-quinazolone monomer, present as its his-oxide salt (bis-anion) or in the presence of a base capable of deprotonating the quinazolone groups,
b) providing a second electrophilic monomer prone to nucleophilic substitution at two sites, and
c) allowing the bis-quinazolone monomer and the second monomer to react in a dipolar solvent to thereby form the polyquinazoline polymer.
In yet another embodiment, the method for forming the polyquinazoline polymers of the present invention comprises providing mixtures of monomers having either a quinazolone nucleus having one activated halide group, and/or bis-quinazolones, to form polyquinazoline co-polymers.
In another aspect of the present invention, a polyquinazoline polymer is provided which comprises repeat units comprising at least one quinazoline nucleus and at least one ether linkage.
In yet another aspect of the present invention, multi-chip modules, capacitors, integrated circuits, films, and fibers formed from the polymers provided in accordance with practice of the present invention are provided.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects and advantages of the present invention will be more fully understood when considered with respect to the following detailed description, appended claims, and accompanying drawings, wherein:
FIG. 1 is a semi-schematic fragmentary cross sectional side view of a multi-chip module provided in accordance with practice of the present invention.
FIG. 2 is a semi-schematic exploded perspective view of a capacitor provided in accordance with the present invention;
FIG. 3 semi-schematic cross-sectional side view of an integrated circuit provided in accordance with practice of the present invention;
FIG. 4 is a semi-schematic perspective view of a multi-filament fiber provided in accordance with practice of the present invention; and
FIG. 5 is a semi-schematic perspective view of a roll of free-standing film provided in accordance with practice of the present invention.
DETAILED DESCRIPTION
This invention is directed to a new class of polyquinazoline polymers, to the monomers which are used for their preparation, to various products formed from the polymers, and to the processes for forming the polymers.
The polymers provided in accordance with practice of the present invention can be formed from a single monomer containing one each of two functional group types, typically called an AB monomer, or from two monomers, each containing two of the same functional groups, typically called type AA and type BB monomers. The terms "type AA monomer," "type BB monomer," and "type AB monomer" are commonly used for describing monomers used in condensation polymerization systems. For example, one such system is described in U.S. Pat. No. 4,000,187, which is directed to the use of Friedlander reactions to prepare polyquinolines by reacting an aromatic amino carbonyl compound containing two sets of ortho-amino aldehyde or ortho-amino ketone functions (in this case, the AA monomer) with a monomer containing two ketone functions having a methylene group adjacent each function (in this case, the BB monomer).
The polyquinazoline homopolymers of the present invention are prepared either from two monomers, i.e., from a type AA monomer and a type BB monomer, or from a single type AB monomer. Polyquinazoline copolymers are prepared from mixtures of two or more type AA monomers with one or more type BB monomers; or one or more type AB monomers with one or more type AA, or one or more type BB monomers; or two or more different AB monomers.
The type AA monomer of the present invention is a bis-quinazolone in which each quinazolone nucleus may be deprotonated to form a nucleophilic oxy anion. As is known in the art, quinazolones exist in two isomeric forms, one bearing a proton on the oxygen atom and the other bearing a proton on the nitrogen atom. Treatment of quinazolones with a base will abstract this labile proton and produce a quinazolone anion, where the negative charge is delocalized between the oxygen and nitrogen atoms. In the present invention the quinazolone anion reacts through the oxygen atom, and the quinazolone anion therefore reacts as a nucleophilic oxy anion. The type BB monomer of the present invention comprises a bis-electrophile, in which each electrophilic group has a leaving group that can be displaced by the quinolone anion. The BB monomers of the present invention are prone to nucleophilic substitution at two sites. Electrophilic groups are typically aryl halides having an electron withdrawing group situated ortho or para to the halide. Electron withdrawing groups useful for the practice of the present invention include, but are not limited to carbonyl, sulfone, nitro, quinoline, quinazolone, and quinazoline. The polyquinazolines of the present invention are formed by allowing the bis-nucleophilic AA monomer to react with the bis-electrophilic BB monomer in a dipolar solvent under conditions where the AA monomer is partially or totally deprotonated.
The type AB monomers of the present invention contain both nucleophilic and electrophilic groups. The AB monomers are comprised of a quinazolone nucleus containing a single activated halide group. The nucleophilic group is the oxy anion of the deprotonated quinazolone. The electrophilic group is the haloquinazolone (or halo quinazoline in the growing polymer chain) and the leaving group is the activated halide. The AB monomers are reacted in the presence of a base in a dipolar solvent.
The general structure of AB type monomers provided in accordance with the present invention is: ##STR1## where one of R 2 and R 4 is OH, and one of R 2 , R 4 , R 5 , and R 7 is a halide selected from the group consisting of halide, ortho-arylhalide, and para-arylhalide, where aryl may be heteroaryl, or substituted aryl. The halide may be F, Cl, Br, or I, preferably, F, or Cl, and most preferably F. The remaining positions on the quinazolone nucleus may be H or may be substituted with any groups (R) n not interfering with the polymerization reaction, including, but not limited to, alkyl, aryl, substituted alkyl and aryl, fluoroalkyl, alkoxy, aryloxy, thioether, ketone, aldehyde, C or O bound ester, C or N bound amide, imide, carboxylic acid, sulfone, cyano (--CN), nitro, and amine.
Non-limiting examples of (AB) monomers useful for practice of the present invention are 2-(4-fluorophenyl)-4-quinazolone, 2-(2-fluorophenyl)-4-quinazolone, 2-(4-chlorophenyl)-4-quinazolone, 2-(2-chlorophenyl)-4-quinazolone, 4-(4-fluorophenyl)-2-quinazolone, 4-(2-fluorophenyl)-2-quinazolone, 4-(4-chlorophenyl)-2-quinazolone, and 4-(2-chlorophenyl)-2-quinazolone, 5-fluoro-2-quinazolone, 7-fluoro-2-quinazolone, 5-fluoro-4-quinazolone, 7-fluoro-4-quinazolone, 5-chloro-2-quinazolone, 7-chloro-2-quinazolone, 5-chloro-4-quinazolone, and 7-chloro-4-quinazolone.
The general structure of the bis-quinazolone (AA) monomers useful in accordance with practice of the present invention which contain two quinazoline nuclei is given by the following general structural formula: ##STR2## where either R 2 and R' 2 , or R 4 and R' 4 are OH, and the remaining positions on the quinazolone nuclei may be H or may be substituted with any groups (R) n not interfering with the polymerization reaction, including, but not limited to, alkyl, aryl, substituted alkyl and aryl, fluoroalkyl, alkoxy, aryloxy, thioether, ketone, aldehyde, C or O bound ester, C or N bound amide, imide, carboxylic acid, sulfone, cyano (--CN), nitro, and amine; and X is a divalent group selected from the group consisting of nil, alkylene, arylene, and --O--, where arylene may be monocyclic or polycyclic, single, multi-ring, or fused ring divalent aryl groups, including, but not limited to phenylene, biphenylene, diphenylether, diphenylamine, benzophenone, naphthalenediyl, fluorenediyl, and the like, and wherein non-limiting examples of alkylene are ethylene (--CH 2 CH 2 --), propylene (--CH 2 CH 2 CH 2 --), 1,4-butylene, and 1,2-propylene.
Non-limiting examples of R groups described above are as follows:
alkyl groups are methyl, ethyl, propyl, isopropyl, tert-butyl, cyclohexyl, stearyl, and docosyl (--CH 2 (CH 2 ) 20 CH 3 );
aryl groups are phenyl, biphenyl, naphthyl, anthracenyl, and diphenylphenyl;
C bound amides are N,N-dimethylaminocarbonyl (--CON(CH 3 ) 2 ), N,N-diphenylaminocarbonyl, piperidinecarbonyl (--CONCH 2 CH 2 CH 2 CH 2 CH 2 ), morpholinecarbonyl (--CONCH 2 CH 2 OCH 2 CH 2 ), and N-methyl-N-phenylaminocarbonyl;
N bound amides are benzoylamino, N-methylacetylamino;
O bound esters are acetyloxy (--OCOCH 3 ) and benzoyloxy (--OCOC 6 H 5 );
C bound esters are methoxycarbonyl (--CO 2 CH 3 ) and phenoxycarbonyl (--CO 2 C 6 H 5 );
alkoxy groups are methoxy, neopentyloxy, and cyclohexyloxy;
aryloxy groups are phenoxy, naphthoxy, and biphenyloxy;
imides are phthalimide, succinimide, and glutarimide;
carboxylic acid groups are --COOH;
fluoroalkyl groups are trifluoromethyl, perfluorobutyl and 2,2,2-trifluoroethyl;
ketones are phenylketone (also called benzoyl), naphthylketone (naphthoyl), methylketone (acetyl), ethylketone (propionyl), tert-butylketone (pivaloyl), isobutylketone, trifluoromethylketone (trifluoroacetyl), methoxyethylketone, benzylketone, phenethylketone, 2,4,6-trimethylphenylketone, pyridinylketone (nicotinoyl), 2-quinolinoketone, and 2-thiopheneylketone; and
aldehyde is --COH.
Non-limiting examples of (AA) monomers useful for practice of the present invention are 6,6'-bis-4-quinazolone, 6,6'-bis-2-phenyl-4-quinazolone, 6,6'-(1,4-phenylene)-bis-4-quinazolone, 6,6'-bis-7,8-benzo-4-quinazolone (R 7 and R 8 bridging), 2,2'-bis-4-quinazolone, 2,2'-(1,4-phenylene)-bis-4-quinazolone, 2,2'-(4,4'-biphenylene)-bis-4-quinazolone, 2,2'-bis-(1,4-tetramethylene)-4-quinazolone, and 2,2-bis-(4,4'-oxydiphenyl)-4-quinazolone, 6,6'-bis-2-quinazolone, 6,6'-bis-4-phenyl-2-quinazolone, 2,2'-(1,3-phenylene)-bis-4-quinazolone, 6,6'-bis-7,8-benzo-2-quinazolone (R 7 and R 8 bridging), 7,7'-bis-4-quinazolone, 4,4'-(1,4-phenylene)-bis-2-quinazolone, 4,4'-(4,4'-biphenylene)-bis-2-quinazolone.
The general formula for the bis-electrophilic monomer is W--Y--W, where W is a halide and Y is a divalent aromatic moiety chosen from
--Ar--,
--Het--, and
--Ar'--A--Ar'--
where Ar is an aryl group activate by electron withdrawing groups such as imide, halide, ketone, and nitro, and --Het-- is heteroaryl, Ar' is a divalent aryl group linked as an ortho-arylene or a para-arylene, and A is a divalent electron withdrawing group such as carbonyl, sulfone, 1,4-dicarbonylbenzene (--CO--C 6 H 4 --CO--), (--CO--C 6 H 4 --O--C 6 H 4 --CO--), and the like. A, Ar, and Ar' may be mononuclear, polynuclear, monocyclic, or polycyclic groups. Some specific examples of --Ar'--A--Ar'-- are 4,4'-benzophenone, and 4,4'-phenylsulfone.
Non-limiting examples of bis-electrophilic (BB) monomers useful as monomers of the present invention are 4,4'-dichlorobenzophenone, 4,4'-difluorobenzophenone, 2,2'-difluorobenzophenone, 2,2'-dichlorobenzophenone, 4-chlorophenyl sulfone, and 6,6'-bis 2-(4-fluorophenyl)-4-phenylquinoline!: ##STR3## Other bis-electrophilic monomers will be apparent to one skilled in the art.
The general procedure for forming the polyquinazoline polymers of the present invention comprises heating the monomer(s) and a base in a solvent and azeotropically removing water (formed by the reaction of the base with the hydroxy groups on the AA or AB monomer). The order of addition of reactants is not important. The amounts of the monomers used to form the polymers of the present invention may be determined by standard formulae known in the art, such as Carother's equation.
In general, (for AA+BB polymerization) while equal molar amounts of AA and BB monomers are normally used, molar ratios other than 1:1 may be used, if desired, to control the MW or end groups. Base is generally added in slight molar excess. For the solvent system NMP/toluene the reflux temperature is about 135° C. (the particular temperature depends on the NMP/toluene ratio, with higher ratio giving higher temperature), and water is collected over a six to eighteen hour period. The toluene or other co-solvent is then removed by distillation and the mixture is heated to greater than about 175° C., (or brought to reflux, about 202° C. for NMP) and held for 12 to 24 hours (or longer at lower temperatures), or until the desired polymer MW is achieved. Pressure is not critical; atmospheric pressure is preferred.
Endcappers may be added at the beginning of the reaction, during the reaction, or near the end of the reaction. The polymer MW may be determined as is known in the art by measurement of viscosity or by gel permeation chromatography (size exclusion chromatography). The reaction is then cooled. The polymer may be recovered from the dope by any technique known in the art, including by precipitation with a non-solvent such as alcohol or water. The non-solvent is preferably chosen to be polar in order to remove fluoride salts which are the by-product of the reaction. It is also preferable to filter the polymer dope before precipitation. In some cases it may be desirable to dilute the dope before filtration or precipitation.
The AB monomer of general formula (1) may be polymerized to give polymers of the following general structures: ##STR4## where Z is optionally substituted aryl or heteroaryl, or nil; x is the number of repeat units and is preferably from 2 to 1,000,000, more preferably from 10 to 10,000, and most preferably from 50 to 1000; the quinazoline groups may be optionally substituted with any groups (R) n not interfering with the polymerization reaction, including, but not limited to, alkyl, aryl, substituted alkyl and aryl, fluoroalkyl, alkoxy, aryloxy, thioether, ketone, aldehyde, C or O bound ester, C or N bound amide, imide, carboxylic acid, sulfone, cyano, nitro, and amine, and n may be 0 to 4. Examples of R groups of the AB monomers are the same as those set forth above for the AA monomers.
The AA monomer of general formula (2) may be polymerized with a bis-electrophilic type BB monomer to give polymers of the following general structures: ##STR5## where X, and R are as above, and Y derives from the BB monomer and is as described above.
Exemplary polymers derived from AB monomers are shown below: ##STR6##
Exemplary polymers derived from AA monomers are shown below: ##STR7##
The following examples are illustrative of the present invention but are not considered limiting thereof in any way.
EXAMPLE 1
Preparation of 4-(4-Fluorophenyl)-2-quinazolone ##STR8##
4'-Fluoro-2-aminobenzophenone (164.5 g, 1.20 mol) is heated with urea (72.09 g, 0.500 mol) at 195° C. (1 h) in NMP (500 mL). The solution is cooled and poured into water (2 L). The product is collected by filtration and dried. The product is purified by recrystallization.
EXAMPLE 2
Preparation of 1,4-bis(2,2'-Quinazolonyl)benzene ##STR9##
A mixture of 2-aminobenzamide (6.81 g, 50 mmol), terephthalaldehyde (6.71 g, 50 mmol), sodium bisulfite (15.6 g, 150 mmol) and dimethylacetamide (50 mL) is stirred at 150° C. (4 h). The mixture is then poured into water (250 mL) and the product is collected by filtration and dried. The product is purified by recrystallization.
EXAMPLE 3
Preparation of 1,4-bis(2,2'-Quinazolonyl)butane ##STR10##
Anthranilic acid (164.5 g, 1.20 mol) is heated with adipamide (72.09 g, 0.500 mol) in dimethylacetamide (500 mL) at 150° C. (4 h). The solution is cooled and poured into water (2 L). The product is collected by filtration and dried. The product is purified by recrystallization.
EXAMPLE 4
Preparation of I From 2-(4-Fluorophenyl)-4-quinazolone ##STR11##
To a three-necked, 500 mL, round-bottomed flask are added 2-(4-fluorophenyl)-4-quinazolone (24.02 g, 100 mmol), anhydrous potassium carbonate (10.4 g, 75 mmol), NMP (210 mL), and toluene (60 mL). The flask is fitted with a mechanical stirring rod set-up, a thermometer, and a Dean Stark trap fitted with a condenser and a nitrogen inlet valve. A nitrogen atmosphere is established and the reaction is heated to reflux (16 h). The toluene and water by-product are removed from the reaction through the Dean Stark trap and the reaction is further heated to 200° C. (16 h). The reaction mixture is then cooled to room temperature and diluted with additional NMP (40 mL). The resulting mixture is poured into acetone (1 L) and the product is collected by filtration. The solid is redissolved in NMP (250 mL) and is coagulated in water (1 L). The solid is again collected by filtration. The solid is then boiled in hot acetone (1 h), filtered, and dried in a vacuum oven at 150° C. (12 H). The letter n defines the number of repeat units of the polymer and may be from 2 to 1,000,000, preferably from 10 to 10,000, and most preferably from 50 to 1000.
EXAMPLE 5
Preparation of I From 2- (4-Chlorophenyl) -4-quinazolone ##STR12##
To a three-necked, 500 mL, round-bottomed flask is added 2-(4-chlorophenyl)-4-quinazolone (25.67 g, 100 mmol), anhydrous potassium carbonate (10.4 g, 75 mmol), NMP (210 mL), and toluene (60 mL) (the addition of a catalytic amount of a radical scavenger such as tetraphenylhydrazine can also be added to the reaction to further enhance the properties of the final polymer, see R. S. Mani, B. Zimmerman, A. Bhatnagar, and D. K. Mohanty, Polymer, 1993, 34, 171-181, and references therein). The flask is fitted with a mechanical stirring rod set-up, a thermometer, and a Dean Stark trap fitted with a condenser and a nitrogen inlet valve. A nitrogen atmosphere is established and the reaction is heated to reflux (16 h). The toluene and water by-product are removed from the reaction through the Dean Stark trap and the reaction is further heated to 200° C. (16 h). The reaction mixture is then cooled to room temperature and diluted with additional NMP (40 mL). The resulting mixture is poured into acetone (1 L) and the product is collected by filtration. The solid is redissolved in NMP (250 mL) and is coagulated in water (1 L). The solid is again collected by filtration. The solid is then boiled in hot acetone (1 h), filtered, and dried in a vacuum oven at 150° C. (12 H). The letter n defines the number of repeat units of the polymer and may be from 2 to 1,000,000, preferably from 10 to 10,000, and most preferably from 50 to 1000.
EXAMPLE 6
Preparation of II From 4-(4-Fluorophenyl)-2-quinazolone ##STR13##
To a three-necked, 500 mL, round-bottomed flask is added 4-(4-fluorophenyl)-2-quinazolone (24.02 g, 100 mmol), anhydrous potassium carbonate (10.4 g, 75 mmol), NMP (210 mL), and toluene (60 mL). The flask is fitted with a mechanical stirring rod set-up, a thermometer, and a Dean Stark trap fitted with a condenser and a nitrogen inlet valve. A nitrogen atmosphere is established and the reaction is heated to reflux (16 h). The toluene and water by-product are removed from the reaction through the Dean Stark trap and the reaction is further heated to 200° C. (16 h). The reaction mixture is then cooled to room temperature and diluted with additional NMP (40 mL). The resulting mixture is poured into acetone (1 L) and the product is collected by filtration. The solid is redissolved in NMP (250 mL) and is coagulated in water (1 L). The solid is again collected by filtration. The solid is then boiled in hot acetone (1 h), filtered, and dried in a vacuum oven at 150° C. (12 H). The letter n defines the number of repeat units of the polymer and may be from 2 to 1,000,000, preferably from 10 to 10,000, and most preferably from 50 to 1000.
EXAMPLE 7
Preparation of III From 1,4-bis(2,2'-Quinazolonyl)benzene and 4,4'-Difluorobenzophenone ##STR14##
To a three-necked, 500 mL, round-bottomed flask is added 1,4-bis(2,2'-quinazolonyl)benzene (18.42 g, 50.0 mmol) and 4,4'-difluorobenzophenone (10.91 g, 50.0 mmol), anhydrous potassium carbonate (20.7 g, 150 mmol), NMP (210 mL), and toluene (60 mL). The flask is fitted with a mechanical stirring rod set-up, a thermometer, and a Dean Stark trap fitted with a condenser and a nitrogen inlet valve. A nitrogen atmosphere is established and the reaction is heated to reflux (16 h). The toluene and water by-product are removed from the reaction through the Dean Stark trap and the reaction is further heated to 200° C. (16 h). The reaction mixture is then cooled to room temperature and diluted with additional NMP (40 mL). The resulting mixture is poured into acetone (1 L) and the product is collected by filtration. The solid is redissolved in NMP (250 mL) and is coagulated in water (1 L). The solid is again collected by filtration. The solid is then boiled in hot acetone (1 h), filtered, and dried in a vacuum oven at 150° C. (12 H). The letter n defines the number of repeat units of the polymer and may be from 2 to 1,000,000, preferably from 10 to 10,000, and most preferably from 50 to 1000.
EXAMPLE 8
Preparation of IV From 1,4-bis(2,2'-Quinazolonyl)butane and bis(4-Fluorophenyl)sulfone ##STR15##
To a three-necked, 500 mL, round-bottomed flask is added 1,4-bis(2,2'-quinazolonyl)butane (17.32 g, 50.0 mmol) and bis(4-fluorophenyl)sulfone (12.71 g, 50 mmol), anhydrous potassium carbonate (20.7 g, 150 mmol), NMP (210 mL), and toluene (60 mL). The flask is fitted with a mechanical stirring rod set-up, a thermometer, and a Dean Stark trap fitted with a condenser and a nitrogen inlet valve. A nitrogen atmosphere is established and the reaction is heated to reflux (16 h). The toluene and water by-product are removed from the reaction through the Dean Stark trap and the reaction is further heated to 200° C. (16 h). The reaction mixture is then cooled to room temperature and diluted with additional NMP (40 mL). The resulting mixture is poured into acetone (1 L) and the product is collected by filtration. The solid is redissolved in NMP (250 mL) and is coagulated in water (1 L). The solid is again collected by filtration. The solid is then boiled in hot acetone (1 h), filtered, and dried in a vacuum oven at 150° C. (12 H). The letter n defines the number of repeat units of the polymer and may be from 2 to 1,000,000, preferably from 10 to 10,000, and most preferably from 50 to 1000.
The polymer compositions of the present invention are generally useful in the area of electronics and microelectronics applications because of their combination of low dielectric constant, low water uptake, high thermal stability and good solubility. The instant polymers are useful for dielectric layers in integrated circuits (IC's) such as planarizers, insulators, passivation layers, encapsulants, adhesives and the like. They are also useful in various wiring board applications, such as printed wiring boards, flexible wiring boards, tape automated bonding substrates, multi-chip modules, dielectrics, other high density interconnect devices, and the like. They may also be used in fabrication of electronic components such as capacitors, resistors, discrete semiconductor devices, inductors, or other devices requiring an insulating layer.
The polymers of the present invention are also useful in electrical applications such as wire coatings and insulation, insulating lacquers, for fabricating molded connectors, switches, enclosures, insulating strips, or the like. Other applications requiring low dielectric constant and good mechanical properties are coatings applications, especially where high thermal stability and transparency are desired, and insulating applications, including conformal coatings and protective layers, potting compounds, and the like. The polymers of the present invention are also useful as adhesives, for example as die attach adhesives, optionally with fillers, or laminate adhesives. The polymers of the present invention are also useful as matrix resins for composites.
The instant polymers may also be used as free standing films, as laminated films, fibers, and coatings.
The following examples of applications for the polymers of the present invention are intended to be illustrative and are in no way limiting.
Referring to FIG. 1, a semi-schematic cross-sectional side view of a multi-chip module 10, provided in accordance with practice of the present invention, is shown. Such multi-chip modules are wiring boards designed to hold several integrated circuit chips (IC's) (not shown) directly without the IC's first being packaged into individual chip carriers. The multi-chip module is typically (but not necessarily) fabricated using photolithographic techniques similar to those used in IC fabrication. The following procedure outlining multi-chip module fabrication is illustrative and many variations are known in the art and may be used with the present invention.
A substrate 12, typically a four- or six-inch silicon or alumina wafer having a plurality of conductors 13 on its surface, is spin-coated with a layer 14 of a polyquinazoline polymer provided in accordance with the present invention. Solvent from the spin-coating process is removed in an oven, and the polyquinazoline layer is cured by heating to a selected temperature for a selected period of time as described above to enhance the solvent resistance of the polyquinazoline layer. Vias (not shown) are cut through the polymer by any of several techniques, for example, laser drilling or patterning and etching. A layer of metal 16, typically copper or aluminum, is deposited and patterned using techniques known in the art to form metal lines with a portion of the metal 16a extending through the via and contacting the conductors 13. A second layer of polyquinazoline 18 provided in accordance with the present invention is spin-coated, dried and cured, completely covering the underlying metal. Vias are cut as above, and a second layer of metal is deposited and patterned. Additional layers of polymer 20 and metal 22 are added by repeating the above procedure. In some processes, it may be desirable to use adhesion promoters to enhance adhesion of the polymer to the silicon substrate or subsequent layers, or to plate the metal lines with chromium or gold before the application of the polymer.
The polymers of the present invention are also useful as dielectric materials in other passive or active discrete electronic components, such as capacitors, resistors, inductors, transformers, diodes, transistors and the like.
Referring to FIG. 2, a semi-schematic exploded view of a capacitor 30 is shown. Dielectric films 32, and 34, comprising a polyquinazoline polymer provided in accordance with practice of the present invention, insulate metal foils 36, and 38, which form the plates of the capacitor. The multi-layer structure is typically wound into a roll 40, and packaged after providing electrical connections (not shown).
The polymers of the present invention may also be used in coating applications such as liquid crystal displays, flat panel TV, light valves, solar windows, and the like. The instant polymers are also useful in optic and electro-optic applications such as optical wave guides, optical fibers, and non-linear optical devices. Electrical applications include wire coatings and wire wrap film, protective and anticorrosion coatings, as resin for connectors, housing, switches, plugs, sockets, or other molded electrical components.
The polymers of the present invention are also useful as interlayer dielectrics for integrated circuits. The low dielectric constant and high thermal stability are advantageous in interlayer dielectric applications. The interlayer dielectric separates the signal-carrying metal layers from each other and/or from the semi-conductor devices of the integrated circuit.
Turning to FIG. 3, there is shown a schematic view of an integrated circuit 42, comprising a semi-conducting device 43, integrated into a silicon wafer 45, metal signal-carrying lines 47, and a polyquinazoline polymer provided in accordance with practice of the present invention serving as insulating dielectric layers 44. The polyquinazoline layers are fabricated using techniques commonly known in the art, including spin-coating followed by curing at elevated temperature.
The polyquinazoline polymers of the present invention are also useful as coatings where high transmission to visible light is desired. Coatings for use in other harsh environments, such as industrial, petrochemical, chemical, are also applications of the instant polymers.
The polyquinazoline polymers of the present invention may also be formed into fibers, by methods known in the art, such as wet spinning, dry spinning, and extrusion, and subject to further treatments such as hot or cold drawing.
Turning to FIG. 4, there is shown a semi-schematic view of a multi-filament fiber 50, comprising a plurality of mono-filaments 52 of a polyquinazoline polymer, provided in accordance with the present invention.
High strength, thermally stable films, optionally uniaxially oriented, may be prepared from the polyquinazoline polymers of the present invention.
Turning to FIG. 5, there is shown a roll 60 of free-standing film 62, formed from a polyquinazoline polymer prepared in accordance with practice of the present invention.
The above-described fibers and films have various uses, including textiles, cord, rope, fibers for use in composites, barrier films, bagging material, electrical and thermal insulation, and release films.
The polymers of the present invention may also be used as matrix resins for composites applications.
The above description of preferred embodiments of polyquinazoline polymers and the monomers useful for forming the polymers are for illustrative purposes. Because of variations which will be apparent to those skilled in the art, the present invention is not intended to be limited to the particular embodiments described above, The invention disclosed herein may suitably be practiced in the absence of any material or composition which is not specifically disclosed herein. The scope of the invention is defined in the following claims. | New polyquinazoline polymers are provided by reacting novel monomers, The polymers incorporate repeat units that have at least one quinazoline nucleus and at least one ether linkage at the quniazoline 2 or 4 position. The quinazoline polymers are prepared by treating a monomer which comprises a quinazolone nucleus having one activated halide group with a base in a dipolar solvent to thereby form the polyquinazoline polymer. | 8 |
RELATED APPLICATIONS
This is a Continuation-in-Part of Ser. No. 11/149,382 filed Jun. 9, 2005, now abandoned, which is a Continuation of Ser. No. 10/370,318 filed Feb. 19, 2003, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a composite for a building material and a method of manufacturing a building material using the composite. More particularly, it relates to a composite for a building material such as a rough wall panel for a bearing wall, a heat-insulating/soundproof panel, and a block material for a mud wall and a flower bed, and a method of manufacturing a building material using the composite.
2. Description of the Related Art
Nowadays, plastic boards, and inorganic boards such as calcium silicate boards and gypsum boards are used as a building material in large numbers. However, the plastic board causes hypersensitiveness to chemical substances due to chemical substances such as formalin generated from the board, which presents a big social problem. Also, for the inorganic board, whose low cost and high function have been realized and which has been capable of being mass-produced, it is difficult to recycle the board after use, and the board is disposed of as industrial wastes without being treated, which presents a big problem. On the other hand, the effective use of various industrial wastes has recently been studied from the viewpoint of global environmental protection. For example, a building material using paper making sludge has been proposed in Japanese Patent Laid- Open No. 2001-11799, an example in which used paper having been broken to pieces and wastes of used synthetic resin sheets are used has been proposed in Japanese Patent Laid-Open No. 2000-302535, and an example in which waste casting sand is used has been proposed in Japanese Patent Laid-Open No. 2000-220247. In any case, however, like the plastic board and inorganic board, the problem of hypersensitiveness to chemical substances and the problem of disposal as industrial wastes after use remain unsolved. Contrarily, a mud wall, etc. using clay, which have been used from ancient times in Japan, not only provide a comfortable living environment in Japan's hot and humid environment because of their high humidity conditioning property but also present little of the problem of disposal as industrial wastes because of its ease of recycling. However, the mud wall, etc. using clay require a long period of time for their work, and also have poor resistance to earthquake, so that the demand for them has decreased year by year.
In view of such a present situation, the inventors have continued studies earnestly and resultantly have found the fact described below. If a building material is manufactured by using a composite for a building material containing diatomaceous earth, waste lumber, and inorganic hardener for cement mud wall, or a composite for a building material further containing field earth, used paper, etc., a building material can be obtained which has a high humidity conditioning property and thus provides a comfortable living environment as in the case of the conventional mud wall, and is easily recycled; for example, it can be reused merely by crushing the obtained building material, and is harmless to global environment because industrial wastes, for example, waste lumber such as lumber chip, sawdust, shavings, and crushed pieces of fallen tree, used paper and/or crushed pieces of used tatami mat and used tile, and crushed earth can also be used as a raw material. As the result of the findings, we completed the present invention.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a composite for a building material containing diatomaceous earth, waste lumber, and inorganic hardener for cement mud wall.
Another object of the present invention is to provide a composite for a building material containing diatomaceous earth, waste lumber, field earth, and inorganic hardener for cement mud wall.
Still another object of the present invention is to provide a composite for a building material containing diatomaceous earth, waste lumber, field earth and inorganic hardener for cement mud wall, and industrial wastes such as used paper and/or crushed pieces of used tatami mat and used tile, and crushed earth as a raw material.
Still another object of the present invention is to provide a composite for a building material which is harmless to living environment and global environment and is easily recycled.
Yet another object of the present invention is to provide a method of manufacturing a building material using the above-described composite for a building material.
The building material obtained from the above-described composite for a building material has a high humidity conditioning property as in the case of the conventional mud wall made of coarse clay because its raw material is a natural material, and is easily recycled by being crushed. Moreover, this building material does not cause hypersensitiveness to chemical substances because it produces no chemical substances, and has a feel of earth so that earthen walls and flower beds made by using this building material integrate well with the appearance of ancient city and are in harmony with beautiful appearance of houses properly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a mold for manufacturing a rough wall panel in accordance with the present invention; and
FIG. 2 is a graph showing a load test result of a rough wall panel in accordance with the present invention. In the FIG. 2 , reference mark A is no chip contained, vertical arrangement, reference mark B is no chip contained, horizontal arrangement, reference mark C is a chip contained, vertical arrangement and reference mark D is a chip contained, horizontal arrangement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention that attains the above objects relates to a composite for a building material containing diatomaceous earth, waste lumber, and inorganic hardener for a cement mud wall, or further containing field earth, etc., and a method of manufacturing a building material using the composite.
The composite for a building material in accordance with the present invention is, as described above,a composite material for a building material containing diatomaceous earth, waste lumber, and inorganic hardener for cement mud wall or containing diatomaceous earth, waste lumber, field earth, and inorganic hardener for cement mud wall, or further containing industrial wastes such as used paper, crushed pieces of used tatami mat and used tile, and crushed earth. The content of the diatomaceous earth is 10 to 50 wt % of all the components, the content of the waste lumber is 5 to 30 wt %, and the content of the inorganic hardener for cement mud wall is 10 to 80 wt %. If the content of the diatomaceous earth is lower than 10 wt %, the strength of building material is undesirably insufficient. If the content of the diatomaceous earth exceeds 50 wt %, the hardness of building material is too high, which makes nailing and sawing difficult to do. If the content of the waste lumber is lower than 5 wt %, it is difficult to nail and saw the building material, and the humidity conditioning property is low. If the content of the waste lumber exceeds 30 wt %, the strength undesirably decreases. Further, if the content of the inorganic hardener for cement mud wall is lower than 10 wt %, the strength of building material is insufficient, and if the content of the inorganic hardener for cement mud wall exceeds 80 wt %, the building material is undesirably too hard. As the diatomaceous earth, commercially available diatomaceous earth is used. As the waste lumber, lumber chip, sawdust, shavings, etc. can be used, and they are preferably used by being crushed as necessary to obtain a homogeneous mixture. As inorganic hardener for cement mud wall can be used, for example, a composition consisting of within the indicated percentage ranges: Portland cement, about 45 to about 60 wt %; an inorganic rapid-curing agent, about 20 to about 27 wt %; an inorganic shrinkage-retarding agent, about 8 to about 10 wt %; an organic pigment, about 10 to about 13 wt %; a powder of silica about 5 to about 7 wt %; and an surface-active agent, about 0.7 to about 0.9 wt %. Preferably, the foregoing example is a composition consisting of Portland cement, about 48.4 wt %; an inorganic rapid-curing agent, about 24.2 wt %; an inorganic shrinkage-retarding agent, about 8.8 wt %; an inorganic pigment, about 12 wt %; a powder of silica about 6 wt %; and an surface-active agent, about 0.8 wt % (manufactured by Chichibu Concrete Industry Co., Ltd.,). As another aspect of the present invention, the composite for a building material contains field earth. The field earth means clayey earth taken from paddy fields and plowed fields. The containing of field earth makes the water holding property of building material high, increases the strength thereof after drying, and makes the building material superior in coloring. As the field earth, Arakida earth and Kyofukakusa earth can be used, and Kyofukausa earth is especially preferable. The content of the field earth should be in the range of 5 to 40 wt %. If the content of the field earth is lower than 5wt %, no effect is achieved, and if the content of the field earth exceeds 40 wt %, the strength decreases undesirably. In addition to the above-described components, the composite for a building material in accordance with the present invention can contain 10 to 30 wt % of industrial wastes such as used paper and/or crushed pieces of used tatami mat and used tile, and crushed earth. If the content of the industrial wastes is lower than 10 wt %, the reuse effect of resources is little, and if the content of the industrial wastes exceeds 30 wt %, the strength of building material decreases undesirably. As the crushed earth, crushed pieces of mud wall, crushed pieces of building material in accordance with the present invention, etc. can be used.
The following is a description of a method of manufacturing a building material in accordance with the present invention. The method will be carried out as described below. Diatomaceous earth and waste lumber or diatomaceous earth, waste lumber and field earth are mixed with water, and further, as necessary, industrial wastes such as used paper and/or crushed pieces of used tatami mat and used tile or crushed earth, and an antibacterial agent and an insecticide are mixed. After the mixture is sufficiently agitated, an inorganic hardener for cement mud wall is put into the mixture just before molding, by which a composite for a building material is prepared and is formed into a panel or a block, and then is dried and cured. As a molding method used in the above-described manufacturing method, slip casting method in which a composite for a building material is slip cast into a mold and a pressure is applied, an extrusion molding method in which a composite for a building material is extruded from an extruding machine, or the like molding method can be used. In manufacturing a large panel such as a rough wall panel for a bearing wall and rough wall panel for heat insulation, the slip casting method is preferable because molding is easy to do in this method. In the slip casting method, as shown in FIG. 1 , a frame 2 of a panel size is prepared by using square steel materials, pressing plates 3 of waterproof plywood are arranged at the upper and lower part of the frame 2 , and a joggle connection 4 is provided at one place, by which a mold 1 is formed. The prepared composite for a building material is cast into the mold 1 , and a weight of 50 to 200 kg is placed on the pressing plate 3 to dry and cure the composite. The mold is released, and the composite is cured in an air-conditioned room to be finished into a product. In particular, in the case where the rough wall panel for a bearing wall is manufactured, it is preferable that a wooden lath plate be embedded to increase the strength when the composite for a building material is slip cast. As the wooden lath plate, a plate-shaped body in which narrow wooden plates are combined into a net shape is used, and the number of embedded wooden lath plates may be in the range of one to three.
Because of its high productivity, the extrusion molding method of the above-described molding methods is used suitably for a block of clayey wall, flower bed, etc. and small heat-insulating/soundproof panel, etc. The extrusion pressure of the extrusion molding machine should be in the range of about 2 to 80 MPa, preferably in the range of 3 to 60 MPa. Also, heating of the composite for a building material to a temperature of 40 to 250° C. before extrusion molding is preferable because the drying process can be carried out smoothly.
As the dry curing method after molding, ventilation dry curing, heated-air dry curing, dry curing under reduced pressure, etc. at an ordinary temperature during three to ten days can be performed. Among them, natural drying such as ventilation dry curing is preferable. In the heated-air dry curing, a temperature in the range of 40 to 250° C., preferably 80 to 200° C. is selected.
As the agitation method used to prepare the composite for a building material, a preform method, a premix form method, a mix form method, etc. can be used. Also, as an agitator, an omni mixer, a Henshel mixer, etc. can be used.
Although the building material manufactured as described above is antibacterial, in order to provide a higher antibacterial property, a publicly-known antibacterial agent should preferably be mixed. The antibacterial agent used may be a synthetic substance or may be a natural substance. Concretely, fenitrothion, fenitron, chlorbenzylate, diazinon, pyrethrum, etc. can be cited. This antibacterial agent is mixed as liquid or powder.
Next, the present invention will be described concretely with reference to examples. The present invention is not limited to these examples. The physical properties such as compressive strength in the following examples complied with the concrete compression test (JIS A 1108), the cement physical test (JIS R 5201),and the test method for a wooden framework bearing wall in accordance with item (c) in Table 1 in Sub-Section 4 of Section 46 of Enforcement Ordinance of Japanese Building Standards Act.
EXAMPLE 1
Two kilograms of diatomaceous earth, 1 kg of lumber chip, and 60 liters of water were put into a mixer, and the mixture was agitated for 30 minutes. After 20 liters of water was further added, 5 kg of inorganic hardener for cement mud wall (manufactured by Chichibu Concrete Industry Co., Ltd., as identified previously) was put in the mixture and was mixed sufficiently to prepare a composite for a building material. A half amount of the composite for a building material was poured into a mold made of square steel materials of 1800 mm×600 mm×30 mm, and one wooden lath plate (wooden lath plate measuring 6 mm×36 mm×1800 mm in which narrow wooden plates, five in the longitudinal direction and ten in the transverse direction, are combined into a net shape) was placed on the composite, and the remaining half amount was poured. Thereafter, the composite for a building material was cured for one day by being pressed using a pressing plate by placing a weight of 60 kg thereon. After mold releasing, the composite was dried naturally on a drying rack, by which a rough wall panel for a bearing wall of 1800 mm×600 mm×26 mm was manufactured. The strength of the panel was measured by the test method for a wooden framework bearing wall in accordance with item (c) in Table 1 in Sub-Section 4 of Section 46 of Enforcement Ordinance of Japanese Building Standards Act. The test result was 2000 Kgf for horizontal arrangement, and 1500 Kgf for vertical arrangement. Also, the vertical arrangement and horizontal arrangement tests of the rough wall panel were conducted. As a result, it was found that this rough wall panel had a higher strength and a higher resistance to earthquake than a three-piece braced wall. Further, the angular deformation between layers relative to the load was examined, with the result that deformation was little. The result is shown in FIG. 2 .
EXAMPLE 2
One kilogram of diatomaceous earth, 2 kg of Kyofukakusa earth, 1 kg of lumber chip, and 60 liters of water were put into a mixer, and the mixture was agitated for 30 minutes. After 30 liters of water was further added, 5 kg of inorganic hardener for cement mud wall (manufactured by Chichibu Concrete Industry Co., Ltd., ) was put in the mixture and was mixed sufficiently to prepare a composite for a building material. A half amount of the composite for a building material was poured into a mold made of square steel materials of about 1800 mm×600 mm×30 mm, and one wooden lath plate (described before) was placed on the composite, and the remaining half amount was poured. Thereafter, the composite for a building material was cured for one day by being pressed using a pressing plate by placing a weight of 60 kg thereon. After mold releasing, the composite was dried naturally on a drying rack, by which a rough wall panel for a bearing wall of 1800 mm×600 mm×26 mm was manufactured. The strength of the panel was measured by the test method for a wooden framework bearing wall in accordance with item (c) in Table 1 in Sub-Section 4 of Section 46 of Enforcement Ordinance of Japanese Building Standards Act. The test result was 2000 Kgf for horizontal arrangement, and 1500 Kgf for vertical arrangement. Also, the vertical arrangement and horizontal arrangement tests of the rough wall panel were conducted. As a result, it was found that this rough wall panel had a higher strength and a higher resistance to earthquake than a three-piece braced wall. Further, the angular deformation between layers relative to the load was examined, with the result that deformation was little. The result is shown in FIG. 2 .
EXAMPLE 3
One kilogram of diatomaceous earth, 2 kg of Fukakusa earth, and 30 liters of water were put into a mixer, and the mixture was agitated for 30 minutes. After 3 kg of used paper, which was dipped in water of 30 liters, was put and mixed, and 30 liters of water was further added, 5 kg of inorganic hardener for cement mud wall (manufactured by Chichibu Concrete Industry Co., Ltd.,) was put in the mixture and was mixed sufficiently to prepare a composite for a building material.
Next, the composite for a building material was molded and cured in the same way as that of example 1, by which a rough wall panel for a bearing wall was manufactured. The strength of the panel was measured by the test method for a wooden framework bearing wall in accordance with item (c) in Table 1 in Sub-Section 4 of Section 46 of Enforcement Ordinance of Japanese Building Standards Act. The test result indicated that the strength was approximately equal to that of the rough wall panel of example 1. Also, the vertical arrangement and horizontal arrangement tests of the rough-coated wall panel were conducted. As a result, it was found that this rough wall panel had a higher strength and a higher resistance to earthquake than a three-piece braced wall. Further, the angular deformation between layers relative to the load was examined, with the result that deformation was less than that of example 2.
EXAMPLE 4
A composite for a building material with the composition given in Table 1 was prepared, and was poured into a mold made of square steel materials of about 900 mm×400 mm×30 mm, by which a heat-insulating panel measuring 900 mm×400 mm×26 mm was manufactured.
TABLE 1
(Unit: kg)
Diato-
maceous
Hard-
Fukakusa
Used
Crushed
earth
Chip
ener
earth
paper
earth
Water
Test
13.9
13.9
20.9
27.9
0
0
111.5
piece 1
Test
13.9
13.9
41.8
20.9
0
0
111.5
piece 2
Test
27.9
13.9
62.7
0.0
0
0
111.5
piece 3
Test
41.8
13.9
62.7
0.0
13.9
0
111.5
piece 4
Test
13.9
13.9
41.8
20.9
0
13.9
111.5
piece
Test pieces were prepared from the obtained panel, and a compression test was conducted. The result is given in Table 2.
TABLE 2
Test piece No.
Maximum stress (Kgf/cm 2 )
1
8.4
2
14.9
3
32.2
4
26.2
5
6.9
As described above, this heat-insulating panel has a high stress and a high resistance to earthquake, and also, unlike a plastic building material, does not cause hypersensitiveness to chemical substances because its raw material is a natural material. Therefore, it is useful as a backing material for interior work or the like. | To provide a composite for a building material capable of manufacturing a building material that is harmless to living environment and global environment and can be recycled. The composite for a building material contains diatomaceous earth, waste lumber, and inorganic hardener, or further contains field earth, and, as necessary, contains used paper and/or crushed pieces of used tatami mat and used tile, and crushed earth. The composite for a building material is prepared by homogeneously mixing the components, and then the building material is manufactured by molding and curing the composite. The manufactured building material has a high humidity conditioning property as in the case of the conventional mud wall made of coarse clay, and is easily recycled by being crushed. Moreover, this building material does not cause hypersensitiveness to chemical substances because it produces no chemical substances, and has a feel of earth so that earthen walls and flower beds made by using this building material integrate well with an appearance of ancient city and are in harmony with beautiful appearance of houses properly. | 2 |
BACKGROUND OF THE INVENTION
This invention relates generally to fifth wheel assemblies for coupling semi-trailers to tractors. More particularly the invention relates to a method and apparatus for assisting the precise positionment of an adjustable fifth wheel carrier assembly.
Large highway freight trailers are usually coupled to an associated tractor by means of a fifth wheel assembly whereby the tractor rear drive axles directly support a portion of the trailer load burden. Usually, the fifth wheel couple and support point is located along the length of the tractor between the rear drive wheels and the front steering wheels thereby distributing the front trailer burden between the driver and the steering wheels. The exact percentage of load desirably placed upon the front steering wheels is a variable dependent upon many factors including the road surface, the tractor equipment, the weather, the weight of the trailer and the whim of the driver.
Some degree of control over these variables is provided by a fifth wheel receiver that is mounted on a slide carriage assembly. The carriage assembly is rail guided and includes an anchoring mechanism for securing the slidable assembly at the desired point along the tractor length between the driving and steering wheel axles.
Finding and setting the fifth wheel carriage assembly at the desired point can be tedious, time consuming, and frustrating. The general procedure is to lock the trailer brakes, release the fifth wheel carriage anchor mechanism, and then drive the tractor forward or reverse until the fifth wheel carriage is at the desired point whereupon the anchoring mechanism is reengaged to secure the fifth wheel carriage at the desired location. When the trailer is heavily loaded, stopping the tractor at the exact location desired for the fifth wheel assembly can be difficult.
It is an object of the present invention, therefore, to teach a method for precisely controlling the terminal point of a position changeable fifth wheel carriage.
Another object of the present invention is to provide a small, conveniently carried, tool adapted for convenient positionment on a fifth wheel carriage slide rail rack as a selectively positionable abutment structure.
Another object of the present invention is to provide a position adjustable fifth wheel carriage assembly having convenient and rapid redistribution of trailer weight on the drive and steering axles of the tractor.
A still further object of the present invention is to provide a method and apparatus for adjusting the position of a fifth wheel slide carriage in one single, positively controlled movement of the tractor.
SUMMARY OF THE INVENTION
Most fifth wheel slide carriage units are guided along a pair of parallel rails having a cogged or hobbed upper edge in the form of a gear rack with a plurality of periodically spaced teeth separated by gaps.
Each tooth period in the rail rack provides an anchor position for the fifth wheel carriage slide assembly. An anchor mechanism secured to the slide carriage unit meshes with the rail rack at the position desired for the fifth wheel carriage assembly.
When a fifth wheel carriage position change is required, slide stop tools of the present invention are positioned on the rail rack in mesh with the teeth to provide a physical abutment structure for engagement by a leading edge of the fifth wheel slide carriage at the desired terminal point. With the trailer coupling pin secured in the fifth wheel receiver socket, the trailer wheel brakes are set. The fifth wheel carriage slide anchor is now released to free the carriage for sliding movement relative to the guide rails. By means of the tractor power unit and drive wheels, the tractor frame mounted rails are moved under the fifth wheel carriage slide assembly until the slide stop tool engages the leading edge of the fifth wheel carriage unit. At this point the fifth wheel carriage anchoring structure is reengaged with the guide rail to complete the fifth wheel position change procedure.
BRIEF DESCRIPTION OF THE DRAWINGS
Relative to the drawings wherein like reference characters throughout the several figures of the drawings designate like or similar structures and elements.
FIG. 1 represents a tractor-trailer assembly equipped with a position adjustable fifth wheel trailer hitch.
FIG. 2 is a plan view of a position adjustable fifth wheel trailer hitch according to the present invention.
FIG. 3 is a side elevation of a fifth wheel trailer hitch assembly according to the present invention.
FIG. 4 is a sectioned elevational view of the invention along the cutting plane 4--4 of FIG. 2.
FIG. 5 is an isolated perspective of a carriage slide anchoring mechanism.
FIG. 6 is a bottom plan view of the present invention slide stop tool.
FIG. 7 is a sectioned end elevation of the present invention slide stop tool as viewed along the cutting plane 7--7 of FIG. 6.
FIG. 8 is a sectioned side elevation of the present invention slide stop tool as viewed along cutting plane 8--8 of FIG. 6.
FIG. 9 is an isolated perspective of a fifth wheel carriage rail rack having the present invention slide stop tool meshed therewith.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Relative to FIG. 1, a highway tractor-trailer unit 10 is shown to include a powered tractor 11 and a trailer 12 connected by a fifth wheel hitch assembly 13 for relative articulation about a vertical axis. Propulsive power of the tractor unit 11 is delivered to driving wheels 14. Tractor directional steering is controlled by front wheels 15. Trailer secured wheels 16 carry the aft end of the trailer load and are served by a braking mechanism that may be engaged independently of the tractor wheel brakes.
To illustrate the objective of a position adjustable fifth wheel unit 13 the value X is shown as the distance between the fifth wheel vertical hitch axis 17 and the tractor steered wheel plane 18. If the fifth wheel hitch axis 17 is shifted to the aft of the tractor by a distance Y the percentage of trailer load carried by the tractor steering wheels is correspondingly reduced and the load carried by the tractor driving wheels 14 is increased.
Such an adjustable position fifth wheel assembly 13 is shown in FIGS. 2 and 3 to include a fifth wheel carrier assembly 20 mounted on a base plate 22. The carrier assembly includes a pair of sled runners 24 having outside and inside runner flanges 34 and 36, respectively. A guide slot for each of the sled runners 24 is formed between the edges of an internal guide plate 50 and opposite base plate edge channels 38.
Each sled runner 24 supports a trunion journal bearing 42 within a journal sleeve 40. The fifth wheel receiver plate 25 is pivotally secured to the sled runners 24 by journal pins 44 through outside and inside pin bosses, 46 and 48, respectively.
As a unit, the fifth wheel coupling 13 is secured to the tractor 11 frame rail by means of anchor brackets 54.
The fifth wheel receiver plate 25 comprises a large load bearing area and a pair of fork tines 26 for structurally defining guide slot edges 28. During the tractor-trailer hitching process these guide slot edges 28 funnel the trailer secured coupling pin 30 to the receiver plate center where it is secured in a pin socket 31 by the pin locking mechanism 32.
Also secured to the base plate 22 along and within each of the sled runner channels are respective rack rails 60. The upper surface face of these rack rails is hobbed or cogged with rack teeth 62 separated at periodic spacings by gaps 64.
Relative to FIGS. 4 and 5, a carrier assembly anchor mechanism 80 is disposed between the sled runners 24 and includes a remotely operated power cylinder 82 and piston rod 83. Locking shoes 84 are secured by respective shanks 85 to the rod and cylinder by yoke couplings 88 and 86, respectively.
The locking shoes 84 each include a head portion 90 and a pair of rack teeth 92. The rail and locking shoe rack teeth 62 and 92, respectively, are of wedge or dove-tailed planform for reasons to be subsequently apparent. Coiled compression springs 94 are disposed around the locking shoe shanks 85 between respective yoke couplings 86 and 88 and the spring seat 96. Spring seats 96 are structurally integral elements of sled runners 24 below locking shoe operating portals 70 through the sled runner web structure. These operating portals 70 are lined by side bearing walls 72 and top bearing walls 74.
The bias of locking shoe springs 94 is to telescopically collapse the piston rod 83 into the cylinder 82 and draw the locking shoe teeth 92 into respective gaps 64 between flanking racked rail teeth 62.
The power cylinder and rod combination is not secured to any other structure but adjustably floats between the bias of springs 94. Actuation of the power cylinder as by pressurized fluid for example, telescopically expands the rod 83 axially from the cylinder 82 against the bias of the shoe springs 94 to displace the locking shoe teeth 92 from respective rail gaps 64 thereby releasing the sled runners 24 for sliding displacement along the rail 60.
When an operator desires to change the relative position of the fifth wheel carrier assembly 20 along the tractor 11 axis, he either blocks the trailer wheels 16 or sets the brakes associated with wheels 16 and activates the anchor shoe teeth 96 from the rack gaps 64. The fifth wheel carrier assembly 20 is now free to slide along the rails 60 which are secured to the tractor unit 11. Control over such sliding movement is regulated by the application of engine power to the tractor drive wheels 14. Resultantly, the tractor unit 11 must be positioned within 0.125 to 0.25 inch of a final objective position relative to the trailor. When the fifth wheel base plate 22 is sliding under an 8 to 10,000 pound load carried by the fifth wheel sled runners 24, it is extremely difficult to position the rack 60 within the narrow tolerance band allowed by the anchor mechanism 80.
Responsive to this difficulty, the invention includes the slide stop tool 100 illustrated by FIGS. 6, 7 and 8. Included is an abutment plate 102 from which are projected at least one rack tooth 104 and a pair of half teeth 106. Between the rack teeth 104 and 106 are a pair of tooth gaps 108. Confinement fences 110 secured across the plate 102 end faces of the abutment plate 102 straddle the rack 60 width when a slide stop rack tooth 104 is meshed within a rack gap 64. A bail 112 provides a convenient gripping surface for placement and removal of the slide stop unit.
Using the slide stop 100 to shift a carrier assembly, the stop 100 is meshed within the appropriate rack gap 64 to position the abutment plate end at the point along the rack length where it is desired to terminate the sled runner end. So positioned, the tractor is driven gently toward engagement of the slide stop with the carrier assembly end whereas relative movement between the trailer 12 connected carrier assembly and the tractor 11 secured guide rails 60 is terminated when the proximate end of the sled runners abut the slide stop 100.
Having fully described our invention and its operation, equivalent and alternative designs will occur to those of ordinary skill in the art. As our invention, however, | The final position of a slideable fifth wheel hitch assembly which permits the relative positions of a tractor and its associated trailer to be adjusted is precisely controlled by a small slide stop tool which engages the rack teeth on a fifth wheel carrier slide assembly guide rail pair. The slide stop is meshed in the gap between rack teeth to provide a quickly and conveniently positioned abutment on the guide rails at the precise location desired for the fifth wheel carrier assembly sled runners. | 1 |
BACKGROUND OF THE INVENTION
The invention pertains to a multifunction tape measure and more particularly, to a tape measuring system contained in a device having two pencil sharpening means, a pencil holder and a memo note pad retainer that are integrally formed as parts of the housing and thereof allowing convenient use of the tape measure.
A conventional tape measure is being used for the taing of measurements for whatever reason or application such as iron works, building trades, indoor decorations, carpentry and furniture design and so on.
When used to take on-the-spot measurements, it is generally necessary to mark down the measurement onto a slip of paper for reference and future use before said measurement is forgotten. Therefore, while working at a job site the worker (measurer) needs to equip himself not only with a tape measure but also writing implements such as paper, pencil and pencil sharpener. Since these tools are odd pieces not integrated with tape measures, it is most often the case that these implements shall be easily misplaced or otherwise forgotten and therefore not readily convenient for use. Often at times a worker (measurer) will, when unable to locate and therefore use these convenient and correct implements, use a substitute that very often is not sufficient or is illegible to the extent that the worker must remeasure that which he has already done to be sure of said measurement(s). Having to do so creates an unnecessary expenditure of time and therefore money, energy and may even deteriorate the worker's attitude thus causing the worker to perhaps become careless.
SUMMARY OF THE INVENTION
In view of such inconveniences and difficulties frequently encountered by an artisan or other persons requiring the taking of measurements on or off the job site, the invention has provided an important object to a multifunction tape measure system having in and of itself the usual functions of a tape measuring apparatus as well as the additional utilities of
1. two pencil sharpeners, one for common pencils and the other for square type or carpenters pencils,
2. a memo pad retainer using paper and P.V.C. or "hard-copy" note pad and
3. a pencil holder that retains the pencil to the tape measure for ready convenient use.
It is the purpose of this invention to accommodate the use of all these implements into one convenient package as it is believed that each of these implements is commonly required in relationship with the use of tape measures and the taking of measurements.
Another object of the present invention is to provide a multifunction tape measure system whereby the design does not alter nor hinder the fitting nor the use of the original measuring tape, but offers new and additional functions where the various additional parts are integrally and inseperably formed with the casing whereby once the measuring tape is appropriately disposed, the additional fittings shall be ready and complete and which require no separate storage or placement and have no likelihood of getting misplaced or otherwise lost, and thus providing very convenient and economical use.
It is yet another object of the present invention to provide a multifunction tape measure system having thereon at least one or two internally integrated or mounted pencil sharpening means, a more than one or two pencil/pen holding parts or memo pad retaining parts in addition to the measuring tape mechanism.
It is a further object of the invention to provide a multifunction tape measure system in which the carpenters or square type pencil sharpening means is provided with a movable safety lid or cover capable of safety guarding against the otherwise exposed sharp cutting knife edge.
Other objects and attendant advantages of the invention shall become evident and more readily apparent and understood from the following detailed specification and accompanying drawings in which:
FIG. 1 is a perspective view of a multifunction tape measuring apparatus constructed in accordance with the invention in the inverted position;
FIG. 2 is a perspective view seen from the rear face of the tape measuring apparatus shown in FIG. 1;
FIG. 3 is a plan view showing the internal construction of the tape measuring apparatus after the removal of a half shell body and the measuring tape control switch;
FIG. 4 is a top view of the tape measuring apparatus;
FIG. 5 is a view seen from the left side of the tape measuring apparatus;
FIG. 6 is a sectional view of the major portion in another embodiment of the tape measuring apparatus depicting the memo pad retainer; and
FIG. 7 is a sectional view of the major portion in still another embodiment of the tape measuring apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference now to the drawings and particularly FIGS. 1-3, the tape measuring apparatus of the present invention is comprised of a plastics-fabricated housing 1 formed after the right and left half members 1a and 1b have been placed one against the other and fastened together by screws 9 or other means, a tape reel 2 with the center being rotatable by a rotary shaft 21 and received in the housing 1 and the circumferential face wound up with a flexible measuring tape 22, a pencil sharpening means 3 mounted in a corner portion on one side face of the housing 1, a pencil trimming (draw knife) means 4 mounted in another corner portion of the housing 1 and intended to trim the square type pencil lead for use in carpentry, a snap-in pencil holding part 5 located at another lateral side of the housing 1, memo pads retaining part 6 located at the front face of the housing 1, a tape control switch 7 mounted on one side face of the housing 1 and a belt clip 8 disposed on the rear side of the housing 1.
The above said reel 2 with tape 22 wound around is rotatably accommodated in the housing 1 in the usual way and the free end of the tape 22 where there is a bent edge is pulled out of an exit 11 of the housing 1 and is then retained at its edge. As with a conventional tape measure, the tape reel 2 is provided therein with a spring (not shown) bestowing upon the tape 22 a tendency of being selectively rewound back into the housing.
The housing 1 is as usual formed with the left and right halves 1a, 1b in combination and capable of holding in between the tape reel 2 in a sandwich manner by means of the chief inner wall in each half. However, according to the present invention, constitution of the housing 1 differs from the arrangement in the conventional tape measure. Here, in the corner portion on one side of the housing 1, for example on the side away from the tape exit 11, there is disposed a rotary pencil sharpener 3. The pencil sharpener 3 comprises a wall 31a forming a shavings collecting compartment 31 located at said corner portion of the housing 1, a sharpening member 32 securely mounted in the compartment 31 with the sharpening hole 33 open on the upper portion shown in the drawing and provided with a blade 34, a shavings outlet slit 35 provided on the top face of the housing 1 shown in the drawing and leading to the compartment 31 and a transversely slidable lid 36 openably covering the outlet slit 35. In the bottom of the housing 1 on the same side as the sharpener 3 is next mounted a pencil trimmer or draw knife 4 in a shavings collecting compartment 41 formed by a wall 41a in another corner portion of the housing 1, a blade 43 removably mounted on a supporting member 42, a shavings outlet slit 44 provided on the housing 1 and leading to the compartment 41 and a lid 45 capable of openably covering the outlet slit 44 and the edge of the blade 43 by sliding transversely.
As is equipped in a usual tape measure, on the back of the housing 1, that is, on the front center of the left side half 1b in this example, there is mounted a resilient holding piece 8 for clipping and hanging on the leather belt, etc. On the front center of the right side half 1a there is located, however, a substantially square-shaped shallow recess or concave part 12 having at the corner part thereof where it is on the same side as the tape exit 11 formed a notch 13 communicating with said concave part 12. The concave part 12 has raised peripheral edges 14 on all sides, and by means of this shallow concave part 12, notch 13 and the raised peripheral edges 14 a memo pad retaining part 6 is constituted for accommodating and supporting thereon a pack 60 of note paper. This note paper pack 60 is coated a portion or whole portion on its back side (in the present embodiment it is on the upper and lower peripheral portions) with an adhesive 61 of temporary stickiness. However, if the peripheral edges 14 are formed in an inwardly bent L-shape, as shown in FIG. 6, to retain said note paper pack 60, use of note paper without backside adhesive 61 will be appropriate. It should also be noted that according to the invention an additional P.V.C. or other suitable material 62 may be mounted for use as a reusable hard-copy note or writing surface and that this surface shall provide itself as a convenient writing surface should the user uses up the readily available paper note pad sheets.
On the same side face of the housing 1 where the sharpener 3 is located there is formed a pen holding part 5 having high raised portions 51 on two sides and the middle formed into a cavity 5 with a dimension slightly larger than the half circle for holding in place a writing implement, such as a pencil or ball pen. In this embodiment, said pen holding part 5 is formed integrally with the housing 1, however, should there be consideration as to the problems in the manufacture of the housing 1 and the selection of materials, it is also likely that a holder 5' be separately formed of resilient plastics or rubber and having an open circular-shaped cavity 52 and next with a powerful adhesive or other suitable mounting means firmly attached to the housing 1.
Having the tape measure apparatus constructed as above, a writing implement can be ordinarily retained in the pen holding part 5 or 5' and note paper pack 60 attached to or placed in memo pad retaining part 6. On way to a job site, with the tape measure apparatus being carried along, since the other instruments such as pen, paper, etc. all together are following on the tape measure, there will be no such troubles to the user as being unable to locate the instruments all because they have been kept separately or they are getting lost or easily scattered about. Even if the instruments are not kept complete prior to going to a job site it still will be possible for the user to find out and make up the required things on the tape measure apparatus. At the same time, when in use the writing implement after it has been used to mark down things on the paper may be replaced in the holder part, which not only is convenient for ready use but shall also not cause interference to the use of the tape. Furthermore, when the pencil lead becomes broken or used up, the sharpener 3 in the tape measure apparatus may be employed for sharpening the pencil and in carpentry work or during special occasion when it is necessary to trim the pencil tip into a flat profile the pencil trimmer 4 can be readily utilized with increased convenience of use. The pencil shavings can be emptied out of the outlet slits 35 and 44 by pushing open the movable lids 36 and 45 and the cleaning is thus easy. Again, since the various pencil shavings collecting conpartments 31 and 41 are completely separated from the tape accommodating compartment, the pencil shavings shall in no way enter the tape compartment. In still another instance, because normally the lid 45 is to cover over the edge of the blade 43 and only when a pencil is to be sharpened will the lid 45 be pushed open, this lid 45 also provides security. From all these efficacies which are not to be seen in a conventional tape measure, it will be most appreciable that the tape measure system of the invention is the most useful contrivance.
The foregoing is a description of the preferred embodiment of the invention and it should be understood that variations may be made thereto without departing from the true spirit of the invention as defined in the appended claims. For example, the configuration of tape measure housing or the position of pencil sharpener or trimmer is varied, or the lid is adapted into one of the openably hinged type or one of the members such as sharpener, pencil trimmer or pen holder is omitted from use or the memo pad retaining part is substituted with a holding piece like the piece 8 for retaining note paper thereon. | A multifunction combination tape measuring device includes a housing and a tape reel rotatably received in the housing and wound thereon with a flexible tape. The device is characterized by the housing being formed integrally into various functional components such as a sharpener and a draw knife for sharpening pencil, a holder for retaining pen or pencil therein and a shallow groove for retaining memo pads thereon and with a hard-copy writing surface made of suitable material such as P.V.C. and mounted thereon to provide a reusable reserve writing surface. Pencil shavings collecting compartments are provided having exits for disposal of shavings. By such an arrangement of the invention it allows the use of tape measure in a most convenient and effective way for a user at any job site. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a deflection apparatus for cathode ray tube of a display, and more particularly it relates to a deflection apparatus for cathode ray tube which shows deflection distortion.
2. Description of the Prior Art
A deflection apparatus for cathode ray tube comprises fundamentally of vertical scanning coils and horizontal scanning coils. There are three basic types of deflection apparatus for cathode ray tube well known in the prior art, which are classified as follows:
(1) A saddle type, in which windings on bobbin are made to form saddle-shaped coils and arranged on the inner surface of the deflection yoke itself.
(2) A semi-toroidal type, in which horizontal scanning coils are prepared in the same manner as the above saddle type, and vertical scanning coils are directly formed toroidally on the surface of the deflection yoke itself.
(3) A slot type, which is one variation of the aforesaid saddle type, in which plural grooves are formed in the radial direction in the deflection yoke and windings are mounted therein.
Among these three, the semi-toroidal type of (2) is the mainstream of the applied for deflection yokes because they result in high efficiency and low resistance for direct current.
An example of the semi-toroidal deflection apparatus in the prior art will now be described with reference to the accompanying drawings of FIG. 1 and FIG. 2. Referring to the drawings, a trumpet-shaped deflection yoke (1) is made of a ferrite core and vertical scanning windings (2) are wound thereabout to form a toroid. A trumpet-shaped insulator (3) is arranged on the inner surface of the deflection yoke (1) and saddle type horizontal scanning coils are arranged thereon. The insulator (3) holds the horizontal scanning coils and at the same time, it holds the deflection yoke too.
As is illustrated in FIG. 1 and FIG. 2, a magnetic field is vertically generated by the horizontal scanning coils and forms a loop of magnetic field through the deflection yoke (1). However, as the vertical scanning windings (17) are arranged in the horizontal magnetic field, eddy-current by the horizontal field is induced on the surface of the vertical windings and causes heat generating problems. In the recent high resolution cathode ray tubes, as they employ a higher frequency to drive horizontal scanning coils at for example 64-120 kHz, the tendency to generate heat is increased. Not only for the semi-toroidal type, two deflection windings generally have an induction heating problem when one of the deflection winding is heated by the magnetic field generated by the other windings.
One or both horizontal scanning coils and vertical scanning coils, or a deflection apparatus for cathode ray tube, which are assembled from these coils on trumpet-shaped ferrite core, are generally supported on a plastic resin frame. Heretofore, it was necessary to employ an expensive heat-resistant plastic material when temperature of the material might rise to or above about 90° C.
THE PURPOSE OF THE INVENTION
The present invention is intended to overcome the previously stated overheating problem in deflection apparatus for cathode ray tube. Another object of the present invention is to provide a deflection apparatus for high precision cathode ray tube which can prevent overheating.
THE SUMMARY OF THE INVENTION
This object is accomplished in accordance with the present invention by a deflection apparatus for cathode ray tube, of a type which includes horizontal scanning coils and vertical scanning coils arranged on the trumpet-shaped deflection yoke, which is characterized by comprising:
a trumpet-shaped deflection yoke on the inner surface of which plural guide grooves are formed in the direction of axis of cathode ray tube, one of the horizontal and vertical scanning coils arranged in the aforesaid guide grooves, a trumpet-shaped insulator arranged on the inner surface of the aforesaid deflection yoke and the other scanning coils arranged on the inner surface of the aforesaid insulator.
In the deflection apparatus of the present invention, deflection windings which are arranged in the aforesaid guide grooves on the inner surface of the deflection yoke are scarcely affected by the magnetic field generated by deflection windings which are arranged on the inner surface of the insulator because the magnetic field from the latter windings directly penetrates into the protuberances relatively formed between the grooves on the deflection yoke. As a result, the heat generation caused by eddy-current loss due to the induction between the windings is decreased, and accordingly, expensive heat-resistant plastic materials need not be employed as the insulator. It is another attainment of the present invention that a high resolution cathode ray tube can be manufactured because the guide grooves on the deflection yoke precisely regulate the position of the deflection windings which are mounted thereon. Furthermore, in another preferred embodiment, hooks may be formed on both opening ends of the trumpet-shaped insulator to support the deflection windings for the other direction in order to increase the accuracy of assembly.
THE BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 illustrates a cross-sectional view of an example of a deflection apparatus in the prior art, which is cut along the direction of axis of cathode ray tube.
FIG. 2 illustrates the other cross-sectional view of the deflection apparatus in FIG. 1 which is cut along the line A--A in FIG. 1.
FIG. 3 illustrates a cross-sectional view of an example of a deflection apparatus of the present invention.
FIG. 4 illustrates an inside view of the deflection yoke of deflection apparatus in FIG. 3.
FIG. 5 illustrates a part of outside view of deflection yoke in FIG. 4.
FIG. 6 illustrates a cross-sectional view of deflection yoke in FIG. 4 which is cut along the line B--B in FIG. 4.
The present invention will now be described further with reference to preferred embodiments. In the following examples, description are given only on the semi-saddle type. However, variations such as exchanging the arrangement of vertical scanning coils and horizontal scanning coils of the example of the preferred embodiment may be made by one skilled in the art without departing from the spirit and the scope of the present invention. The present invention may also be applied to the saddle-saddle type. Moreover, in the following examples, description will be given for such a case as the number of turns of winding for vertical scanning coils being smaller than that for horizontal scanning coil. However in the high frequency use, the number of turns of winding for vertical scanning coils may be larger. Also such case is included in the scope of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 3 illustrates a cross-sectional view of an example of a deflection apparatus of the present invention. As it fundamentally corresponds to the deflection apparatus in FIG. 1, the same reference numbers are given to similar members for these figures. Herein, the deflection apparatus comprises: a trumpet-shaped deflection yoke (1), toroidal-shaped vertical scanning winding (2) which wound around the aforesaid deflection yoke (1), a trumpet-shaped insulator (3) which is arranged on the inner surface of the aforesaid deflection yoke (1) and saddle type deflection winding (4) which is arranged on the inner surface of the aforesaid insulator (3). The insulator (3) is made of plastic resin to support not only the horizontal scanning windings, but also deflection yoke therewith.
The deflection yoke which embodies the present invention is illustrated in FIG. 4, 5 and 6. The deflection yoke of the present invention has spaced plural guide grooves on the inner surface of it, which extend in the direction of the axis of the cathode ray tube. In the area between the grooves, protuberances (6) are formed. The vertical deflection windings (2) are contained in the aforesaid grooves (5). The number of turns of the windings to be assigned to each groove (5) is decided in order to meet the specification of the deflection coil for manufacturing the deflection apparatus to attain the precise electro-magnetic deflection and good repeatability in production. As is illustrated in FIG. 6, the vertical windings (2) do not protrude from the surface of the deflection yoke due to grooves. Hence, the magnetic field which is generated by the horizontal scanning coils can directly penetrate into protuberances (6) of the deflection yoke when they are assembled as in FIG. 3. A similar kind of the deflection yoke illustrated in FIGS. 4-6, were applied in the prior art for slot type of deflection apparatus as formerly described. However, it should be taken heed that the manner of usage in the prior technique was much different from that of the present invention. That is to say, in the deflection apparatus in the prior art, though two kinds of winding were arranged in the grooves on the same yoke, a complicated composition was employed such that an insulating spacer as interposition inserted into each groove for the insulation of each winding after one of the winding was settled. In spite of high accuracy of the deflection apparatus of this complicated type, it resulted in high production costs.
The trumpet-shaped plastic resin insulator (3) which is arranged onto the inner surface of the deflection yoke (1) contains the horizontal scanning windings along the inner surface of it. In this case of embodiment, it is preferred to provide hooks at predetermined intervals at both ends of the insulator (3) to support the vertical scanning coils thereon. Due to the employment of this type of insulator, high precision electro-magnetic deflection can be attained with good repeatability by setting a predetermined appropriate relationship between positions of windings and hooks, and number of windings.
As another embodiment of the present invention, the vertical scanning coils may be made to form that of saddle type utilizing the grooves on the deflection yoke. The effect and result are the same as the aforementioned embodiment.
With the manner described above, deflection apparatus was made and measured for heat generation. Inductances of employed horizontal scanning coils and vertical scanning coils were 90 uH (LH) and 6 mH (LV) respectively and measured sweep frequencies for horizontal and vertical scanning were 64 kHz and 60 Hz respectively. The deflection apparatus was assembled on a cathode ray tube with 20 inch and 90° deflection angle. The rising temperature ΔT at the vertical scanning coil was measured and listed in the the following table. For the comparison, the semi-toroidal type and the saddle-saddle type deflection coils in the prior art were also measured to list therein.
type of scanning apparatus: ΔT
Semi-toroidal type: 27° C.
Saddle-saddle type: 25° C.
Present invention: 20° C.
Herein, ΔT is the rising temperature at vertical scanning coil.
As is shown in the table, the deflection apparatus incorporated with the present invention can successfully prevent rising temperature by induced heating. In addition to above improvement, it can be manufactured with better repeatability in production for more precise magnetic field determined by the accuracy of deflection yoke in comparison with the saddle-saddle type and the toroidal-saddle type (semi-toroidal type ) because one of windings is arranged in the guide grooves of the deflection yoke itself.
Furthermore, to improve the scanning apparatus of the present invention to the level comparable to that of the type of which both windings are arranged in the grooves on the deflection yoke, hooks may be formed on the periphery of the opening ends of the trumpet-shaped insulator to retain specified turns of the deflection windings on respective hooks of predetermined specified addresses. In accordance with this further improvement, both orthogonal scanning coils can be made to generate an accurate magnetic field and to attain the reliable insulation without any problems which were experienced in the prior art. | A deflection apparatus for cathode ray tube is provided, which comprises deflection yoke with guide grooves, deflection windings for scanning in one direction in said grooves, deflection windings for scanning in the other direction and an insulator between both types of windings. It attains high accuracy deflection with less distortion without any induced heating problem due to protuberances made relatively between grooves. | 7 |
FIELD OF THE INVENTION
This relates to a method and apparatus for searching databases of a variety of types.
BACKGROUND OF THE INVENTION
In today's economies, data is generated, gathered, and stored at an ever-accelerating rate. Financial markets trade with varying stock prices, scientists decode the human genome, patents are filed, and each of these events is reported in some publication, or stored in some database. The ability to access these different sources of information, and to combine them, is becoming crucial for making informed decisions. Ignoring the available information, on the other hand, can result in bad investments, scientific efforts being wastefully repeated, and intellectual property rights being violated. Clearly, the list of advantages of having access to relevant information, and the respective list of disadvantages of not having this information, can be extended ad infinitum.
At the same time, providing access to relevant information is a challenging technical problem. Data is stored in distributed locations and varying formats. It is stored in structured databases, electronic libraries, or even on pages of the World Wide Web. Moreover, different information sources use different vocabularies and have different degrees of credibility.
Information retrieval techniques have been developed to find relevant documents in electronic libraries. These techniques have been widely deployed and refined in order to search for information on the World Wide Web. Users formulate queries by typing in keywords that are related to the information they want to find. For example, if a user is searching for a listing of the law firms in the Palo Alto area, she might provide the keywords “LLP” and “Palo Alto”. If the user is lucky, she will retrieve a listing of all law firms in the Palo Alto area. Very likely though she will also have to scan through pages that provide irrelevant information, like news articles about a Palo Alto based software company suing a Seattle based software company. Moreover, relevant information, like a listing of law firms based in neighboring Menlo Park, might not be retrieved.
These retrieval problems are the subject of considerable academic interest. See, for example, the Proceedings of the Annual International ACM SIGIR Conferences on Research and Development in Information Retrieval.
Whereas the problem of guessing a document's relevance given a list of keywords is “just” difficult, searching a structured database by entering keywords is in most cases absolutely impossible. As an example, consider a database that stores all sales transactions of a department store chain. Assume a manager of this company wants to promote the sales clerk that generated the highest revenue in the previous year. In order to find this sales clerk the database system has to scan all sales transactions, add up the sales for each clerk, and find the clerk with the highest amount of total sales. Obviously, searching the database using keywords could never yield an answer to the manager's query.
Database management systems can be queried using sophisticated query languages. These query languages are expressive enough to formulate a query that would answer the manager's question in the previous example. For instance, using the relational query language SQL the query might look as follows:
CREATE VIEW Totals AS
SELECT employee-id, SUM(sales-amount) AS total-sales
FROM Transactions
GROUP BY employee-id
SELECT employee-name
FROM Employees, Totals
WHERE Employees.employee-id = Totals.employee-id
AND total-sales
>= ALL (SELECT totals-sales FROM Totals)
This query accesses just a single database. Data in this database is stored in a single common format. Clearly, query languages that allow formulating queries across multiple databases or across multiple formats, or that allow combining information from structured databases, electronic libraries, and the World Wide Web, are even more complex. Non-technical users, like managers in a department store chain, obviously cannot be expected to formulate their information requests in these complex query languages.
SUMMARY OF THE INVENTION
The present invention describes an approach that allows the formulation of complex queries using a simple keyword-based user interface.
In accordance with the invention, a library of query templates and a dictionary that relates keywords to more abstract concepts are first prepared on a computer system. Each template contains one or more typed variables. A query is then generated by entering into the system one or more keywords. Each keyword is abstracted to a concept. Advantageously, each concept may be further refined, for example, by additional abstraction, or by picking one concept from several candidates, or by successive abstraction and rejection of different keywords until an acceptable concept is found. Next, for the concepts that are obtained, the system finds all query templates that can use those concepts. The variables in the query templates are then instantiated with those concepts or with the keywords used to form the concepts. The user then selects the most appropriate query from among the instantiated query templates.
The invention may be practiced in formulating queries to access any set of information sources. It is particularly useful to use the invention to access distributed, heterogeneous databases which do not have a single standardized vocabulary or structure.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages of the present invention will become more readily apparent from the following detailed description, which should be read in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram of a representative computer system on which the present invention may be practiced; and
FIG. 2 is a flowchart demonstrating one method of implementing the invention on the computer system depicted in FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown a representative computer system 10 on which the present invention may be implemented. Computer system 10 includes central processing unit (“CPU”) 12 , memory unit 14 , one or more storage devices 16 , one or more input devices 18 , display device 20 , communication interface 22 , and printer 24 . A system bus 26 is provided for communicating between the above elements.
Computer system 10 illustratively incorporates an IBM-compatible or Apple-compatible personal computer, but one skilled in the art will understand that computer system 10 is not limited to a particular size, class or model of computer. CPU 12 illustratively is one or more microprocessors such as a Pentium™ or Pentium II™ microprocessor available from Intel or a 68000 microprocessor available from Motorola. Memory unit 14 typically includes both some random access memory (RAM) and some read only memory (ROM).
Storage devices 16 illustratively include one or more removable or fixed disk drives, compact discs, DVDs, or tapes. Input devices 18 illustratively include a keyboard, a mouse, and/or other similar device. Display device 20 illustratively is a computer display, such as a CRT monitor, LED display or LCD display. Communication interface 22 may be a modem, a network interface, or other connection to external electronic devices, such as a serial or parallel port. For many applications of the invention, it is anticipated that this interface will include a connection to a local area network and the Internet. Printer 24 is a hard copy output device such as a laser printer, dot matrix printer, or plotter.
The computer system of FIG. 1 is used in accordance with the invention to formulate queries to one or more informational databases stored on storage devices 16 or accessible via communication interface 22 on other storage devices not shown. Software and data used in formulating these queries are preferably stored in one or more storage devices 16 . The software is a program which abstracts keywords supplied by a system user and converts them to instantiated query templates from which the user may select one or more queries for use in accessing the information database(s). The data that is stored includes a library of query templates and a database dictionary that relates keywords to concepts.
A keyword is a sequence of characters. For example, the keyword “Ibuprofen” is a sequence of the characters “I”, “b”, “u”, “p”, “r”, “o”, “f”, “e”, and “n”. A concept, on the other hand, is a conceptual or real-life entity. For example, the concept Ibuprofen is a nonsteroidal anti-inflammatory agent with analgesic properties used in the therapy of rheumatism and arthritis. In order to represent concepts in a computer system, a unique identifier or name is assigned to every concept of interest. For example, the concept Ibuprofen might have the unique identifier C020740. For ease of presentation, we will use the word ‘concept’ in this application to also mean the computer representation of a concept.
Several keywords might refer to a single concept. For example, both the keyword “allergy” and the keyword “hypersensitivity” refer to the same concept. Also, a single keyword might refer to several concepts. The abstraction from keywords to concepts is ambiguous in these cases. For example, the keyword “cold” might refer to the concepts Obstructive Lung Disease, Common Cold, or Cold Temperature.
Concepts can be organized in an “is a”-hierarchy, also called ontology. More specific concepts are related by an “is a” relationship to more general concepts. For example, the concept Asthma has an “is a” relationship with the concept Allergy, and the concept Allergy has an “is a” relationship with the concept Disease. Moving from a more general concept to a more specific concept is called ‘refinement’. Moving from a more specific concept to a more general concept is called ‘generalization’. In the example, concept Asthma is a refinement of concept Allergy, and concept Disease is a generalization of concept Allergy.
A flowchart illustrating the invention is shown in FIG. 2 . Step 110 represents the preliminary process of creating a library of query templates and a database dictionary which associates keywords with more general concepts. The library and database dictionary are stored in one or more storage devices 16 of the computer system.
Each of the query templates in the library comprises three entries:
(i) A textual presentation of the query template with variables. This textual presentation, with variables being instantiated, is shown to the user. The variables in the textual presentation are typed, meaning that only certain instantiations of the variables are allowed.
As an example, consider the following textual presentation with typed variables X and Y:
Can X be used to treat Y?
X: Pharmacologic Substance
Y: Symptom
Ibuprofen and Lower Back Pain are possible instantiations of X and Y, respectively, because Ibuprofen is a Pharmacologic Substance and Lower Back Pain is a Symptom. The instantiated textual presentation in this example is:
Can Ibuprofen be used to treat Lower Back Pain?
On the other hand, Lower Back Pain and Ibuprofen is not a possible instantiation of X and Y respectively, because Lower Back Pain is not a Pharmacologic Substance, and Ibuprofen is not a Symptom. As can be seen, the typing of the variables makes it possible to distinguish between useful queries like “Can Ibuprofen be used to treat Lower Back Pain” and nonsense queries like “Can Lower Back Pain be used to treat Ibuprofen?”
(ii) A mapping from the instantiations of the variables in (i) to queries. The queries might be formulated in a database query language like SQL or OQL. More generally, queries are any kind of executable computer code, like PERL scripts or C++ programs that gather information from databases or other information sources. The execution of the generated query is supposed to gather and process all the information in the same way a human expert would do in order to answer the question asked in (i).
The simplest form of a mapping from instantiations to query plans is a textual replacement in a predefined database query. Continuing with the previous example, the following might be a predefined SQL query:
SELECT effectiveness
FROM DrugInformation
WHERE drug=‘X’ AND symptom=‘Y’
A textual replacement of X by Ibuprofen and Y by Lower Back Pain yields the following SQL query:
SELECT effectiveness
FROM DrugInformation
WHERE drug=‘Ibuprofen’ AND symptom=‘Lower Back Pain’
This query could be sent to a database with a relation named “DrugInformation” that has at least the three attributes “drug”, “symptom”, and “effectiveness”. The query would gather all information known on the effectiveness of Ibuprofen to treat Lower Back Pain.
(iii) Statistical information for ranking different matching query templates. This information might include the computational cost of executing the query plan, the cost of accessing the information sources required for executing the query plan, usage patterns, user preferences or user privileges.
A typical keyword dictionary is a thesaurus which relates specific words to more general concepts. This dictionary advantageously is hierarchical with several levels of increasing abstraction. An illustrative such dictionary is the Metathesaurus and Semantic Network described below.
To formulate a query, a user enters one or more keywords at step 120 . Illustratively, the queries are entered into the computer system using a keyboard and correct entry is confirmed via display device 20 . Advantageously, a graphic user interface is used to facilitate the entry of the keywords.
The system then proceeds at step 130 to abstract the keywords(s) into one or more concepts. Where the keyword is associated with multiple concepts, the system advantageously presents the user with a listing of at least the most likely concepts and the user has the opportunity at step 140 to further refine his entry by selecting the most appropriate concept. Preferably, the presentation of alternative concepts is in ranked order where the ranking is determined by pre-specified criteria. One such criterion is frequency of selection during previous uses of the database dictionary.
As suggested in FIG. 2, the abstraction process may involve multiple steps. For example, as indicated by the loop around step 130 , a keyword may be abstracted into a concept and the concept may be further abstracted into a higher level concept. As indicated by the loop around steps 120 and 130 , the process may involve the successive entry of different keywords, the abstraction of each keyword in turn, and a selection from the resulting concepts of the one concept that is deemed most appropriate.
Following selection of the concepts, the concepts are then matched at step 150 with the templates to identify those templates that can accept the selected keywords and concepts. Matching is performed by checking the library of query templates to determine if any templates have variables that will accept the concepts that have been abstracted from the keywords.
The templates that are identified are then instantiated with the keywords and/or concepts at step 160 and the instantiated templates are presented to the user. Advantageously, the presentation is made via a display and a graphical user interface; and the instantiated templates are presented in a ranked order determined by pre-specified criteria. Several possible criteria have been described above.
Finally, at step 170 , the user selects one or more of the instantiated query templates for further use as a query to the information sources that are stored in storage devices 16 or that are accessible through communication interface 22 .
The invention may be practiced with all manner of dictionaries and ontologies. A particularly useful context in which the invention may be practiced is in formulating queries using the Unified Medical Language System (UMLS). This system includes a Metathesaurus, a Semantic Network, an Information Sources Map and a SPECIALIST lexicon. The Metathesaurus integrates more than thirty biomedical thesauri and its most recent release contains over 330,000 concepts that are named by more than 739,000 terms. The Semantic Network contains 135 semantic types and 51 relationships. The Metathesaurus contains information for abstracting keywords to concepts, and for refining and generalizing concepts. The Semantic Network is useful for providing the types and supertypes used in the query templates.
UMLS was developed between 1986 and 1994 under the sponsorship of the National Library of Medicine. Considerable information about UMLS is available at the National Library of Medicine's web site: www.nlm.nih.gov. UMLS is also featured in a recent issue of the Journal of the American Medical Informatics Association, Vol. 5, No. 1, (January/February 1998). See, especially, B. L. Humphreys et al., “The Unified Medical Language System: An Informatics Research Collaboration,” pp. 1-11; M. Joubert et al., “UMLS-based Conceptual Queries to Biomedical Information Databases: An Overview of Project ARIANE,” pp. 52-61, both of which are incorporated herein by reference.
An illustrative example of how the present invention might use UMLS to formulate queries is as follows. An illustrative graphical user interface for use in this application is set forth in Table I.
TABLE I
ADD
SELECT
GENERALIZE
REFINE
DELETE
RESET
The interface includes at least a display area and a row of user selectable “keys.” The display area is a workplace which displays information that the user is working with including an entry from the keyboard. The user selected keys typically are used by a mouse-controlled cursor and permit the user to manipulate the contents of the display. Illustratively, the keys include an ADD key which adds an additional concept to the query, a SELECT key which enables the user to select one or more alternatives presented on the screen, a GENERALIZE key which enables the user to instruct the system to generalize a concept displayed on the screen, a REFINE key which enables the user to refine a concept, a DELETE key which enables the user to delete a concept, and a RESET key which returns the user to the starting point for new keyboard entry.
In the case of UMLS, the Metathesaurus provides the keyword dictionary that relates keywords to concepts. This is available from the National Library of Medicine and preferably is stored in a storage device in the user's computer system, or on a server accessible through a local area network or the Internet. The library of query templates advantageously is prepared by a system administrator to accommodate the particular needs of a company or it is obtained from commercial sources.
We will consider by way of example the formulation of a query about respiratory disorders. The use starts by typing in “cold.” This is displayed on the graphical user interface as shown in Table II.
TABLE II
COLD
ADD
SELECT
GENERALIZE
REFINE
DELETE
RESET
To enter this keyword, the user selects the ADD key.
In response, the system abstracts the keyword “cold” and presents the abstraction to the user for his consideration. Since “cold” is a very general term, there are several possibly relevant concepts and all of these are presented to the user as illustrated in Table III.
TABLE III
□ CO 24117 (Lung Diseases, Obstructive)
□ CO 09443 (common cold)
□ CO 09264 (cold temperature)
ADD
SELECT
GENERALIZE
REFINE
DELETE
RESET
The numbers that are prefixed to each concept are concept numbers used in the Metathesaurus. To select one of these concepts, the user uses the cursor to mark “Common Cold” and then selects the SELECT key.
The system returns a screen which includes a detailed description of the common cold. This description is the contents of the Metathesaurus entry on the common cold.
To further develop the query, the user then selects the GENERALIZE key. The system returns the screen shown in Table IV.
TABLE IV
□ CO 42769 (virus disease)
□ CO 35204 (respiration disorder)
ADD
SELECT
GENERALIZE
DEFINE
NEXT
DELETE
To select one of these concepts, the user uses the cursor to mark “respiration disorders” and then selects the SELECT key.
The system returns a screen with a detailed description of respiration disorders obtained from the Metathesaurus.
To further develop the query, the user decides to make an additional entry. He types in “melatonin” and then selects the ADD key. This gives the system enough information to make a match with an available query template.
Accordingly, the system returns the screen set forth in Table V.
TABLE V
□ Respiration Disorder
□ Melatonin
□ Is respiration disorder affected by melatonin?
ADD
SELECT
GENERALIZE
DEFINE
NEXT
DELETE
This, however, is not what the user has in mind, so he uses the cursor to mark “melatonin” for further development and selects the REFINE key.
The system proceeds to display more detail about melatonin by returning on the screen of Table VI a list of Different types of melatonin.
TABLE VI
□ Respiration disorder
□ Melatonin
□ 2 - phenylmelatonin
.
.
.
□ 2 - iodomelatonin
□ 2 - chloromelatonin
□ Is respiration disorder affected by melatonin
ADD
SELECT
GENERALIZE
REFINE
DELETE
RESET
One of these is of interest to the user and so he uses the cursor to mark both “respiration disorder” and “2 phenylmelatonin” and selects the SELECT key.
Again, this gives the system enough information to attempt to make a match with a query template. Accordingly, the system searches the query templates for a possible match.
Upon making the search, the system finds a match and proceeds to instantiate the query template with the terms “respiration disorder” and “2-phenylmelatonin.” It then returns the screen of Table VII.
TABLE VII
□ Respiration disorder
□ 2 - phenylmetonin
□ Is respiration disorder affected by 2-phenylmelatonin?
ADD
SELECT
GENERALIZE
DEFINE
NEXT
DELETE
This completes the formulation of the query and the user may then use the query to access information stored in the databases of interest to him.
To formulate a new query, the user selects the RESET key.
As will be apparent to those skilled in the art, numerous variations of the invention may be practiced within he scope of the invention. | A library of query templates and a dictionary that relates keywords to more abstract concepts are first prepared on a computer system. Each template contains one or more typed variables. A query is then generated by entering into the system one or more keywords. Each keyword is abstracted to a concept. Advantageously, each concept may be further refined, for example, by additional abstraction, or by picking one concept from several candidates, or by successive abstraction and rejection of different keywords until an acceptable concept is found. Next, for the concepts that are obtained, the system finds all query templates are then instantiated with those concepts or with the keywords used to form the concepts. The user then selects the most appropriate query from among the instantiated query templates. The invention may be practiced in formulating queries to access any set of information sources. It is particularly useful to use the invention to access distributed, heterogeneous databases which do not have a single standardized vocabulary or structure. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to model aircraft; and, more particularly, to toy gliders which have action imparted to them by a user's hand or by a launching device such as a catapult or by any other device capable of imparting action. The present invention also relates generally to mechanically or electromechanically remote controlled model aircraft.
2. Description of the Prior Art
Prior art multiple configuration model aircraft kits achieved a variety of configurations and planforms by adaptably using a relatively small number of parts. The present invention, however, will further reduce the number of parts in a multiple configuration model aircraft kit and will generally improve the overall desirability of the product.
The prior art embodied in U.S. Pat. No. 4,698,041 shows a multiple configuration model aircraft having a plane surfaces which may support other plane surfaces via suitable connectors. It also shows fuselage pieces always being utilized as fuselage pieces and plane surfaces always being utilized as plane surfaces. The prior art multiple configuration model aircraft additionally allows at least one configuration wherein all of the parts in the kit are not used, leaving disconnected parts to be misplaced or lost.
SUMMARY OF THE INVENTION
An object of the present invention is to provide simplified and alternative structure for a multiple configuration model aircraft. In simple form the model aircraft kit of the present invention has component parts comprising a fuselage and a nose weight, a main wing, and a horizonal stabilizer which may alternatively be used as an additional fuselage. By incorporating releasable connector means, the component parts of the kit may be assembled such that the model aircraft obtains standard, canard, and flying wing configurations as desired.
Another object of the present invention is to provide a multiple configuration model aircraft kit wherein all component parts of the kit are fully utilized in all configurations, leaving no extra parts to be misplaced.
These and other objects of the present invention will become more apparent in the following description of the prefered embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1, 2 and 3 are perspective views illlustrating the configurations of a first embodiment.
FIG. 4 is a separated view of the component parts of the embodiment illustrated in FIGS. 1 through 3.
FIGS. 5, 6, 7 and 8 are perspective views illustrating many of the possible configurations of a second embodiment.
FIG. 9 is a separated view of the component parts of the embodiment illustrated in FIGS. 5 through 8.
FIG. 10 is a perspective view of one of the pair of releasable connectors depicted in FIGS. 5 through 8.
FIG. 11 is a perspective view of one of the pair of fuselage aligners depicted in FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A First Embodiment
A model aircraft may be hand launched, launched from an appropriate catapult or other suitable device, and may be mechanically or electromechanically remote controlled. The launching means is not shown in the drawings.
Referring to FIGS. 1 through 3, a first embodiment of the aircraft kit is shown. This kit may be used to form a flying wing 10, as shown in FIG. 1, or two different aircraft configurations 110 and 210, as shown in FIGS. 2 and 3. The model aircraft 10 has a primary lifting surface comprising a wing panel 12 attached to the fuselage 13 by means of a slot 16. The fuselage 13 is a planar member of elongate configuration with the slot 16 extending in the direction of elongation. Wing panel 12 has a longitudinal centerline and left and right wing portions symmetrical about the centerline and is preferably made of scorable and foldable material such as foam polystyrene sheet. The end sections 18 of the wing panel 12 are scored and turn upward along rearwardly converging fold lines 20. The fuselage 13 has an attached weight 22 which facilitates proper aerodynamic balance during flight and cushions against shock from a frontal impact.
A model aircraft 110 which is similar to the configuration of the model aircraft 10 depicted in FIG. 1 except that the configuration in FIG. 2 employs a different fuselage 114 with a horizontal stabilizer 113 at the front of the fuselage. This fuselage 114 is a second planar member wiht an elongate body portion having a front end portion and an enlarged rear end portion and provided, in the body portion, with two slots extending in the direction of elongation, and in the rear end portion, with a third slot also extending in the direction of elongation. The horizontal stabilizer 113 of this configuration is the planar member 13 which forms the fuselage in the FIG. 1 configuration. Wing panel 112 is attached to the fuselage 114 by means of a slot 117. The fuselage has a transverse slot 130 extending through the body of the fuselage near the front end of the fuselage. The end sections 118 of the wing panel 112 are turned upward along foldlines 120 similar to the corresponding parts of FIG. 1, or they may be extended straight out. The fuselage 114 has an attached weight 122 which has its companion part in FIG. 1.
FIG. 3 depicts a model aircraft 210, which is similar to the configuration depicted in FIG. 2 except that a fuselage 214 has a rear slot 234 that receives a rear horizontal stabilizer 213. Wing panel 212, slot 216, end section 218, foldline 220, weight 222 and forward transverse slot 230 are similar in function and composition to their companion parts depicted in FIG. 2. The fuselage 214 can be used as the fuselage depicted in FIG. 2, since it accommodates two slots 234 and 230.
Referring to FIGS. 1 through 4 and more specially to FIG. 4, component parts 310 are assembled providing various configurations of the model aircraft 10, 110 and 210. These component parts 310 are a fuselage 314, a wing panel 312, wing tips 318, foldlines 320, a horizontal stabilizer or fuselage 313 and a weight 322. The fuselage 314 has preferrably a forward transverse slot 330, a central slot 317 and a rear slot 334. The horizontal stabilizer or fuselage 313 has a slot 316.
It is understood and is readily apparent from viewing FIGS. 1 through 4 that the component parts 310 are considered in combination as model aircraft kit capable of producing at least the various configured model aircraft 10, 110 and 210 when the component parts 310 are particularly assembled. It is equally apparent that the part 313 may be alternately used as a horizontal stabilizer or a fuselage.
A Second Preferred Embodiment
Referring to FIGS. 5 through 8, a second embodiment of the aircraft kit is illustrated. The kit of this embodiment may be used to form a flying wing 410, as shown in FIG. 5, or a number of different aircraft configurations 510, 610, 710, as shown in FIGS. 6, 7 and 8. The model aircraft 410 has a primary lifting surface comprising a wing panel 412 attached to a fuselage 413 by means of a slot 416. Wing appendages 414 and 415 are connected to the tips of wing panel 412 by a pair of releasable wing appendage connectors 421. The fuselage 413 has an attached weight 422. Each wing appendage connector 421 is preferably made of plastic and has a slot which receives a wing appendage 414 or 415. The wing appendage connectors 421 also have another slot into which wing panel 412 is inserted at a suitable angle.
Referring to FIG. 6, a model aircraft 510 is similar to the configuration of the model aircraft 410 depicted in FIG. 5 except that the configuration of FIG. 6 employs a different fuselage 511 consisting of subparts 514 and 515 with a horizontal stabilizer 513 at the front of the fuselage. Horizontal stabilizer 513 corresponds to the fuselage 413 of FIG. 5 and has a slot 516. Horizontal stabilizer 513 is also shown in a moved position near the rear of fuselage 511.
Fuselage subpart 515 is a duplicate of fuselage subpart 514. Only fuselage part 514 will be described. Fuselage part 514 has a transverse slot 517 approximately in the center of the fuselage 514 which receives wing panel 512. The fuselage part 514 further includes a transverse slot 530 located near the front of the fuselage 514 and a transverse slot 534 located at the rear of the fuselage part 514. Horizontal stabilizer 513 is inserted through slot 530 and the corresponding slot of fuselage subpart 515. Weight 522, corresponding to weight 422 of FIG. 5 joins fuselage subparts 514 and 515 together. Wing appendage connectors 521 (only one visible) are positioned on the trailing edge of wing panel 512.
FIG. 7 depicts another configuration of a model aircraft 610 which is similar to the configuration depicted in FIG. 6 except that the fuselage subparts 614 and 615 are split outboard of the wing centerline 609 and except that nose weight 622 consists of two parts 623 and 624 attached to the front of fuselage parts 614 and 615 respectively. Wing panel 612, horizontal stabilizer 613, slots 616, 617, 619, 630, 634, and 635, and wing appendage connectors 621 (only one visible) all have similar functions and compositions to their companion parts as shown in FIG. 6.
FIG. 8 depicts yet another configuration of a model aircraft 710 which has a rearward wing 712 and a forward wing consisting of parts 714 and 715. Rearward wing 712 is attached to fuselage 713 by means of a slot 716, forward wing parts 714 and 715 are attached to fuselage 713 by connectors 721. Connectors 721 have three slots which receive wing parts 714 and 715 and fuselage 713. Wing parts 714 and 715 have slots 730 and 731, 717 and 719, and 734 and 735 respectively, and weights 723 and 724 are attached to wing parts 714 and 715 respectively.
Referring to FIGS. 5 through 9 and more specifically to FIG. 9, component parts 810 are assembled providing various configurations of the model aircraft 410, 510, 610 and 710. These component parts 810 are a wing panel 812, a first planar member of elongate configuration having a slot extending in the direction of elongaion and usable either as a horizontal stabilizer of fuselage 813, a composite fuselage 811 consisting of subparts 814 and 815, each of which is a second elongate member having a front end portion and an enlarged rear portion, and provided, in the body portion, with two slots extending in the direction of elongation, and in the rear end portion, with a third slot also extenidng in the direction of elongation, releasable connectors 821 which connect fuselage subparts of plane surfaces 814 and 815 to wing panels 812 or to fuselage or horizontal stabilizer 813, and a weight 822 consisting of subparts 823 and 824. The fuselage subparts 814 and 815 have preferably forward transverse slots 830 and 831, central slots 817 and 819 and rear slots 834 and 835. The horizontal stabilizer or fuselage 813 has a slot 816. Wing panel 812 has a pair of notches 825 and a pair of notched tabs 826 which align fuselage subparts 814 and 815 when fuselage subparts are deployed as shown in FIG. 7.
FIG. 10 illustrates one of the pair of connectors 821 which connect fuselage subparts 814 and 815 to wing part 812 as shown in FIG. 5. Connector 821 may also connect fuselage subparts 814 and 815 to fuselage or horizontal stabilizer 813 as shown in FIG. 8. Connector 821 has a pair of slots 840 for receiving, in the first instance, a wing panel 812 and a fuselage subpart of plane surface 814 or 815 as depicted in FIG. 5, and in the second instance, both plane surfaces of fuselage subparts 814 and 815 as shown in FIG. 8. Slot 845 receives fuselage 813 corresponding to fuselage 713 in FIG. 8. If the configuration of FIG. 8 is not desired, slot 845 of connector 821 may be eliminated (for drag reduction).
FIG. 11 illustrates one of the pair of fuselage aligners 826. Aligner 826 has slot 827 which allows tabs 828 to be folded along foldlines 829. With fuselage subparts 814 and 815 in place as shown in FIG. 7 and pulled back into forward notches 825, tabs 828 are then displaced away from slots 817 and 819. The forward notches 825, and rearward folded tabs 828 comprising aligners 826 prevent lateral movement of fuselage subparts 814 and 815 along wing panel 812.
The first embodiment as detailed in FIGS. 1 through 4 reveals simplified sructure for a three fold multiple configuration model aircraft. The second preferred embodiment as detailed in FIGS. 5 through 11 reveals a multiple configuration model aricraft in which no fuselage parts or no plane surface parts remain unattached or are left unutilized in any configuration.
It is understood that the described preferred embodiments are illustrative of some of the may specific embodiments which represent applications and principals of the present invention. Clearly, numerous and varied other arrangements may be devised by those skilled in the art without departing from the spirit and scope of the invention. | A multiple configuration model aircraft kit which enables the purchaser to assemble a plurality of model aircraft configurations, uses a relatively small number of components. The components of the model aircraft kid comprise at least one wing or primary lifting surface, one stabilizer and one fuselage or two secondary plane surfaces, and connector means. One of the secondary plane surfaces may alternately function as a fuselage or as a flight surface. Releasable connecting means are used to join the components thereby providing a plurality of configurations. Twin secondary plane surfaces may be provided which may be used alternately as wing tip flight surface extensions, dual fuselages, or as other flight surfaces. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention:
The present invention relates to a refrigerator containing a plurality of storage boxes vertically arranged, with prescribed space provided in a heat-insulating box and, more particularly, a refrigerator capable of separately controlling a storage temperature of each of the storage boxes.
2. Description of the Prior Art:
When preserving vegetables, fruit, meat, fish and other perishable foods (hereinafter referred to as the "foods") for a prolonged period of time at temperatures near freezing point in a refrigerator, or gradually thawing frozen foods, it is generally necessary to restrain a change in the refrigerator storage temperature as little as possible and to control to restrain the evaporation of water content from the foods.
In order to meet this need, there is preferably adapted a refrigerator of such a double-walled structure that storage boxes for storing foods are formed, through a required space defined between this heat-insulating box and the storage boxes, within a heat-insulating box which forms a refrigerating chamber, and a cold air is circulated from a evaporator into the space, thereby cooling the storage boxes.
The optimum refrigerating temperature differs with the kind of the foods, such as vegetables, fruit, meat and fish to be stored. Namely, for the prolonged preservation of the foods without deteriorating their freshness, it is essential to store the foods at their optimum refrigerating temperature. For this purpose, a plurality of storage boxes are formed in the heat-insulating box of the refrigerator of the double-walled structure, and each of the storage boxes is cooled to different storage temperature through a refrigeration system corresponding thereto, thereby enabling the most suitable storage of different kinds (the optimum refrigerating temperature varies) of the foods.
In this case, the refrigerator requires as many refrigeration systems as the storage boxes provided therein. This, however, has the drawback that the use of a large refrigerator including a larger number of storage parts will be demanded, resulting in a higher manufacturing cost. Moreover, there is such a drawback that because of the operation of a plurality of refrigeration systems, power consumption will increase.
OBJECT OF THE INVENTION
In view of the above-described drawbacks inherent in the heretofore known refrigerators of double-walled structure which contain a plurality of storage boxes inside of the aforementioned heat-insulating box, it is an object of the present invention to provide a low-cost refrigerator which is designed to perform respective temperature control of the storage boxes.
SUMMARY OF THE INVENTION
The present invention has been accomplished in an attempt to resolve the problems mentioned above and attain the object by providing a refrigerator having a heat-insulating box which has a plurality of opening sections and a heat-insulated door provided at each of the opening sections; a plurality of storage boxes disposed vertically through a prescribed space within the heat-insulating box, and having opening sections open correspondingly to the aforesaid opening sections; and a evaporator disposed on the upper storage box in the heat-insulating box, the refrigerator, comprising: a first passage which is defined in a space in the interior of the heat-insulating box to guide cold air from the evaporator downwardly, and a second passage which guides the cold air that has flowed, downwardly in the first passage, returning to the evaporator; a partition plate which is disposed within the first passage to divide the passage into a passage which communicates the first passage with the second passage in order to allow the flow of the cold air in contact with the upper storage box, and a passage communicating with the second passage, allowing the cold air to flow into the upper storage box without contacting the upper storage box; a regulating means which is disposed in a cold air passage from the evaporator, and regulates the flow of the cold air into the passage; and a cold air introducing means disposed in the passage, the cold air introducing means being operated to let a part of the cold air from the evaporator flow into the passage without being regulated by the regulating means.
According to the refrigerator of the present invention, as explained above, the passage for cooling the upper storage box and the passage for flowing the cold air for cooling the lower storage box are separately defined, and the cold air introducing means is operated to flow the cold air into the cold air passages to cool the lower storage box. It is, therefore, possible to separately cool the storage boxes by controlling the operation of the cold air introducing means. That is, the storage temperature of the storage boxes can be separately controlled. This storage alone, therefore, can preferably store a plurality of foods to be preserved at different optimum storage temperatures. In addition, since only one refrigeration system is sufficient, manufacturing cost can be lowered and power consumption decreased.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partly longitudinal sectional perspective view showing a part of an upright refrigerator according to a preferred embodiment of the present invention;
FIG. 2 is a longitudinal sectional side view of the refrigerator shown in FIG. 1;
FIG. 3 is a longitudinally sectional front view of the refrigerator shown in FIG. 1;
FIG. 4 is a cross-sectional plan view of the refrigerator shown in FIG. 1;
FIG. 5 is a longitudinally sectional side view, on an enlarged scale, of a major portion showing the upper part of the refrigerator;
FIG. 6 is a longitudinally sectional side view of a major portion showing the upper and lower opposing sections of storage boxes;
FIG. 7 is a longitudinally sectional side view of a refrigerator according to another embodiment of the present invention; and
FIG. 8 is a longitudinally sectional side view of a major portion showing a damper mounting section, in an enlarged section, shown in FIG. 7.
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter preferred embodiments of the refrigerator according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a perspective view showing an upright refrigerator, partly longitudinally sectioned, according to a preferred embodiment of the present invention. FIG. 2 is a longitudinal sectional side view of the refrigerator shown in FIG. 1. And FIG. 3 is a longitudinal sectional front view of the refrigerator shown in FIG. 1.
As shown in these drawings, a refrigerator 10 has an outer box 12 having square opening sections 12a, 12a which are vertically arranged with a prescribed amount of spacing provided therebetween and are widely open at the front side, an inner box 14 installed in this outer box 12 with a prescribed amount of space provided therebetween and widely open also at the front side, and a heat-insulating material 16, such as foamed urethane, filled in between these boxes 12 and 14. In the inner box 14 of this heat-insulating box 18 are vertically arranged the upper storage box 22 and the lower storage box 24 through a heat-shielding member 38, 38 which will be described later on with its inner wall 20 and a required space 20 provided
The storage boxes 22 and 24 have square opening sections 22a and 24a which are open at the front correspondingly to the square opening sections 12a and 12a formed in the heat-insulating box 18. At the front of the heat-insulating box 18 is installed a heat-insulated door 26 correspondingly to each opening section 12a of the heat-insulating box 18 as shown in FIG. 2, and freely opens and closes this opening section 12a. The storage boxes 22 and 24 are produced of a heat-conduction metal sheet, such as a stainless steel.
At the inside bottom of the inner box 14, as shown in FIG. 3, is attached a support member 19 which projects out upwardly to a prescribed height from the bottom surface at the center of the bottom in the direction of width thereof. On this support member 19, the lower storage box 24 is mounted, providing a bottom space 44 between the lower storage box 24 and the bottom of the inner box 14. On the inside back surface of the inner box 14, as shown in FIG. 4, a pair of storage box guides 34, 34 of L section are opposingly installed, apart from each other by the size of width of the storage box 22. These guides 34, 34 are vertically installed for nearly the overall length of the inside space of the inner box 14. Between the guides 34, 34, the back of the storage boxes 22 and 24 are commonly fitted.
Between the back of the storage boxes 22 and 24 and the storage box guides 34, 34 and the inside wall of the inner box 14, as described later, there is provided a back passage 36 which functions as the first passage for guiding the cold air downwardly to cool the storage boxes 22 and 24. The back passage 36 is divided by a partition 42, which is described later on, into an upper back passage 36a located on the back side of the upper storage box 22 and a lower back passage 36b located on the back side of the lower storage box 24. Furthermore, the width of the storage boxes 22 and 24 is set smaller than the inside dimension of the inner box 14, thereby defining, as shown in FIG. 4, side passages 46, 46, which function as the second passage for guiding the cold air upwardly to cool the storage boxes 22 and 24, on both sides of the storage boxes 22 and 24. Namely, the space 20 formed between the inside wall of the inner box 14 and the outside wall of the storage boxes 22 and 24 is constituted of the back passage 36, the bottom space 44 and the side passages 46, 46.
The space provided between the inside ceiling surface of the inner box 14 and the ceiling surface of the upper storage box 22 is separated into two chambers 37 and 39 by a partition wall 30 as shown in FIG. 2. In the first chamber 37 communicating with the back passage 36 is mounted a evaporator 28 which communicates with a refrigeration system not illustrated and circulates refrigerant from the refrigeration system to a built-in evaporator. This refrigeration system is set such that refrigerator operation will be controlled on the basis of a temperature sensed by a temperature sensor 62 mounted inside of the upper storage box 22.
The second chamber 39 communicates with the side passages 46, 46. In this chamber 39 are installed fans 32 in positions corresponding to a plurality of openings 30a (two in this embodiment) which are provided in the partition wall 30. This fan 32 is disposed so as to blow the air towards the first chamber 37; therefore, driving the fan 32 draws the air from the side passages 46, 46, which then comes in contact with the evaporator 28 through the opening 30a, thus becoming cold air to be blown out into the back passage 36.
At the bottom of the condenser 28 mounted in the first chamber 37, as shown in FIG. 2, a drip tray 33 is set to discharge water dripping from the evaporator 28 out of the refrigerator. Between the bottom of this drip tray 33 and the ceiling surface of the upper storage box 22, a cold air passage 51 is formed for the circulation of a part of the cold air from the evaporator 28 in this cold air passage 51. The partition wall 30 has a plurality of holes 30b drilled in positions corresponding to the cold air passages 51, so that the cold air partly circulating in the cold air passage 51 through the holes 30b may be led into the second chamber 39.
On both the right and left side edges in the upper and lower opposing surfaces of the upper storage box 22 and the lower storage box 24, as shown in FIGS. 1 to 3, shield members 38, 38 are opposingly inserted extending nearly for the entire length in the direction of depth of the storage box 22 (24), these shield members 38, 38 forming a horizontal passage 40 of a required dimension between the upper and lower opposing surfaces of the storage boxes 22 and 24. This horizontal passage 40 closed at the front and at both sides, as shown in FIG. 2, communicates only with the back passage 36 in order to introduce the cold air flowing downwardly in the back passage 36. That is, the horizontal passage 40, together with the back passage 36, forms the second passage in which the cold air flows downwardly.
The shield member 38, as illustrated, consists of a -shaped first shield plate 38a and a second shield plate 38b, both of which are installed with a partition plate 50 inserted therebetween. The first shield plate 38a is provided with holes 60 drilled for communication with the side passage 46, flowing the cold air that has entered the upper passage 56 formed in the horizontal passage 40, out into the side passage 46 as described later on.
In the upper back passage 36a on the back side of the upper storage box 22 and the horizontal passage 40, the partition plate 50 having an inverted L section is commonly inserted as shown in FIG. 2, separating the passages 36a and 40 double. Namely, the vertical part 50a of the partition plate 50 is inserted in the upper back passage 36a. This upper back passage 36a is separated with the vertical section 50 into a first cold air passage 52 which guides the cold air in contact with the back of the upper storage box 22 and a second cold air passage 54 which guides the cold air out of contact with the upper storage box 22. Also, the horizontal section 50b of the partition plate 50, with its right and left ends held between the first shield plate 38a and the second shield plate 38b, extends as far as the front end of the horizontal passage 40, separating the horizontal passage 40 into an upper passage 56 communicating with the first cold air passage 52 and a lower passage 58 communicating with the second cold air passage 54.
By the way, it is advised that the partition plate 50 be produced of a low heat-conductive material so that the storage boxes 22 and 24 will be subjected to thermal effect each other. Also, as a means for preventing the thermal effect between the storage boxes 22 and 24, the partition plate 50 may be lined with a heat-insulating material.
The top end of the vertical part 50a of the partition plate 50 projects upwardly only by a required length above the ceiling surface of the storage box 22, and into the first chamber 37 as shown in FIG. 5. Between the condenser 28 and the vertical part 50a is disposed a restriction plate 64 as a restricting means extending downwardly from the ceiling surface of the inner box 14 by a prescribed length and throughout the entire length, in the direction of width, of the inner box 14, parallelly with the vertical part 50a. The lower end of this restriction plate 64 is set at a level below the top end of the vertical part 50a, so that the cold air coming out from the condenser 28 will never enter the second cold air passage 54 except when the fan motor 66 described later is not operating.
Therefore, the cold air flowing out from the condenser 28 towards the back passage 36 goes only into the first cold air passage 52. This cold air, thus flowing downwardly in the first cold air passage 52 to cool the back of the upper storage box 22, flows into the upper passage 56, where the cold air cools the bottom of the upper storage box 22. Also the cold air that has entered the upper passage 56 flows out into the side passages 46, 46 through the holes 60, 60 drilled in the first shield plate 38a, 38a, going upwardly in the side passages 46, 46 while cooling both sides of the upper storage box 22 and returning into the condenser 28. In this manner the refrigeration cycle is repeated to cool only the upper storage box 22. The storage temperature control of the upper storage box 22 is effected by stopping the operation of the refrigeration system when the temperature sensor 62 has sensed a preset temperature as described above.
On the inner wall of the horizontal passage 40 in the inner box 14 which faces the lower passage 58, as shown in FIGS. 2 to 6, the partition 42 is projectingly installed in parallel with the horizontal section 50b of the partition plate 50, dividing the lower passage 58 into an upper circulation path 58a and a lower circulation path 58b. The back passage 36 also is separated, by the same partition 42, into two passages: an upper back passage 36a and a lower back passage 36b, such that, as described later, the flow of the cold air which is flowing downwardly in the second cold air passage 58, is diverted by the partition 42 toward the lower passage 58. The outside diameter of this partition 42 has been set, as shown in FIG. 3, so that both sides of the second shield plates 38b, 38b come in contact with each other and that there is provided a gap of prescribed dimension communicating between the upper circulation path 58a and the lower circulation path 58b at the projecting end side.
Therefore, it is possible to distribute the cold air flowing downwardly in the second cold air passage 54, throughout the ceiling surface of the lower storage box 24 through the partition 42 as described later, thereby improving the cooling efficiency of the storage box 24. The provision of the partition 42 is not an essential requirement of the present invention; the object of this invention can preferably be accomplished without the partition 42.
In the lower back passage 36b located below the partition 42 is mounted a fan motor 66 as a means for introducing the cold air through the mounting bracket 68 as shown in FIG. 6. This fan motor 66 is so set as to blow out the air that has been drawn in from the lower circulation path 58b, into the lower back passage 36b side. That is, when the fan moror 66 is driven, a negative pressure is built up in the lower passage 58 and the second cold air passage 54 by which the cold air coming from the condenser 28 is partly drawn into the second cold air passage 54 over the top end of the vertical part 50a of the partition plate 50, going around the lower end of lower restriction plate 64.
The cold air flowing downwardly in the second cold air passage 54 strikes the partition 42, going into the upper circulation path 58a of the lower passage 58. From the forward end of this partion 42, the cold air flows through the lower circulation path 58b, then being blown out into the lower back passage 36b via the fan motor 66. Also, the cold air currents flowing into the lower back passage 36b go downwardly in contact with the back of the lower storage box 24, as shown in FIG. 3, being blown out into the bottom space formed under the bottom of the lower storage box 24. Thence the cold air rises in the side passages 46, 46 which communicate with the bottom space 44, while cooling each of the storage boxes 22 and 24, repeating the cycle to return to the evaporator 28.
Namely, the lower storage box 24 is cooled only when the fan motor 66 is driven, and therefore it is possible to cool the upper storage box 22 and the lower storage box 24 separately. The operation of the fan motor 66 is controlled in accordance with the temperature sensed by the temperature sensor 70 disposed in the lower storage box 24, thereby maintaining a constant storage temperature of the storage box 24.
Next, FIGS. 7 and 8 show another embodiment of the refrigerator of the present invention, wherein a damper 72 is used as a means for controlling the storage temperature of the lower storage box 24.
As shown in FIG. 7, the top end of the vertical part 50a of the partition plate 50 is set so as to be positioned nearly at the same level as the ceiling surface of the upper storage box 22, such that the cold air from the evaporator 28 is branched off into the first cold air passage 52 and the second cold air passage 54. Below the partition 42 is located the lower back passage 36b, in which a barrier plate 74 is disposed as a regulating means capable of shutting off the cold air currents in the lower back passage 36a and the lower circulation path 58b, between the outer wall of the lower storage box 24 and the inner wall of the inner box 14. This barrier plate 74, as shown in FIG. 8, is provided with an opening 74a of a required size in a suitable position, and with a damper 72 as a means for introducing the cold air by freely opening and closing this opening 74a.
Furthermore, beneath the damper 72, there is disposed an actuator 76 which controls the opening and closing operation and the amount of opening of the damper 72. This actuator 76 is designed to be controlled in accordance with a temperature sensed by the temperature sensor 70 mounted in the lower storage box 24. Therefore the actuator 76 is driven on the basis of the temperature sensed by the temperature sensor 70; when the damper 72 is opened, the lower circulation path 58b and the lower back passage 36b open to each other through the opening 74a, admitting the cold air to go around the lower storage box 24.
Function of Embodiment
Next, the operation of the refrigerator according to the embodiment will be explained. First, to cool only the upper storage box 22 of the refrigerator according to the embodiment shown in FIG. 1, the refrigerator is operated with the fan motor 66 kept at a stop. The air in the storage compartments on the side passages 46, 46 side is drawn in by the fan 32, being sent into the evaporator 28 through the opening 30a in the partition wall 30. In this evaporator 28, the air is cooled by the heat exchanger, then being blown out into the back passage 36. The cold air from the condenser 28 partly circulates in the cold air passage 51 formed between the drip tray 33 and the ceiling surface of the upper storage box 22, accomplishing a so-called short cycle to cool the ceiling surface of the storage box 22.
The cold air coming into the back passage 36, as shown in FIG. 5, is retricted by the restriction plate 64 and the vertical part 50a of the partition plate 50, flowing all into the first cold air passage 52. The cold air that has entered the first cold air passage 52 flows downwardly in contact with the back of the upper storage box 22, striking the horizontal section 50b of the partition plate 50 and being diverted to flow into the upper passage 56. The cold air that has entered the upper passage 56 flows in contact with the bottom of the upper storage box 22 for heat exchange and then goes out into the side passages 46, 46 through the holes 60, 60 drilled in the first shield plates 38a, 38a.
The cold air that has flowed out into the side passages 46, 46, being warmed (as compared with the cold air at the outlet of the evaporator 28) by heat exchange with the upper storage box 22, goes upwardly in the side passages 46, 46 in contact with both sides of the upper storage box 22 for heat exchange, then returning into the evaporator 28 to repeat the cycle.
With the repetition of cold air recirculation, the storage temperature in the upper storage box 22 gradually lowers. When this storage temperature has reached a preset temperature of the temperature sensor 62, the temperature sensor 62 senses it, stopping the operation of the refrigeration system to always maintain the storage temperature above a preset temperature. When the cold air circulation has stopped and the storage temperature has increased to a required temperature range, this temperature rise is sensed by the temperature sensor 62, which starts the refrigeration system again, thereby constantly keeping the storage temperature by cooling the upper storage box 22.
Next, when cooling the storage boxes 22 and 24, the fan motor 66 disposed below the partition 42 is driven, thus building up a negative pressure in the second cold air passage 54 and the lower passage 58. As a result of the establishment of this negative pressure in the second cold air passage 54, a part of the cold air delivered from the evaporator 28 goes round under the restriction plate 64 and over the top end of the vertical part 50a, flowing into the second cold air passage 54. Furthermore, since a part of the cold air flows into the first cold air passage 52, the cold air circulates around the upper storage box 22 similarly as described above, cooling the storage box 22.
The cold air branched off into the second cold air passage 54 flows downwardly to the position of the partition 42 without effecting the heat exchange with the upper storage box 22, and strikes this partition 42, being changed in the direction of flow. After flowing downwardly along the partition 42 in the upper and lower circulation paths 58a and 58b of the lower passage 58, this cold air is fed out into the lower back passage 36b located below the partition 42 through the fan motor 66. At this time, the cold air flows in contact with the ceiling surface of the lower storage box 24, making heat exchange, but not in contact with the bottom of the upper storage box 22, thereby efficiently cooling the lower storage box 24.
The cold air that has entered the back passage 36 again flows downwardly in contact with the back of the lower storage box 24 for heat exchange, then being blown out into the bottom space 44. Here, the cold air comes in contact with the bottom of the storage box 24. Furthermore, when rising in the side passages 46, 46, the cold air comes in contact with both sides of the storage boxes 22 and 24 to cool these storage boxes 22 and 24, then returning to the evaporator 28 again to repeat the refrigeration cycle. Since the cold air that has entered the bottom space 44 is warm as a result of heat exchange with the lower storage box 24, the cold air will not accumulate at the bottom of the heat-insulating box 18, but efficiently circulates. When the cold air repeatedly circulating around the lower storage box 24 has lowered the storage temperature of the storage box 24 as low as the preset temperature, the temperature sensor 70 senses it, thereby stopping the fan motor 66. Therefore, no negative pressure will be built up in the second cold air passage 54 and the lower passage 58 and accordingly the cold air delivered out from the evaporator 28 flows only into the first cold air passage 52. In this stage, the lower storage box 24 comes to be not cooled. Also, when the cold air circulation to around the upper storage box 24 has stopped to raise the storage temperature of the storage box 24 to the prescribed temperature range, the temperature sensor 70, sensing this temperature rise, produces a signal to restart the fan motor, thus enabling restarting the circulation of the cold air to around the lower storage box 24 in order to maintain a constant storage temperature.
In this embodiment, the refrigerator is set to stop the refrigeration system when the storage temperature of the upper storage box 22 has lowered to the preset temperature. When cooling the storage boxes 22 and 24, therefore, it is necessary to determine the preset temperature of the temperature sensor 62 installed in the upper storage box 22 lower than that of the temperature sensor 70 disposed in the lower storage box 24.
Because the upper storage box 22 and the lower storage box 24 can be cooled separately by controlling the operation of the fan motor 66, it is possible to separately control the storage temperature of the storage boxes 22 and 24. Furthermore, the refrigerator according to the present invention has such an advantage that since the cold air can be distributed in contact with the whole bottom surface of the upper storage box 22 and the whole ceiling surface of the lower storage box 24, the cooling efficiency of the upper and lower storage boxes 22 and 24 and the time required to cool the storage boxes 22 and 24 to the preset temperature can be decreased, thereby enabling lowering the running cost.
Next, when the refrigerator according to this embodiment shown in FIG. 6 is operated to cool the upper storage box 22 alone, the refrigerator is operated with the damper 72 fully closed. With the damper 72 fully closed, the air flow between the lower circulation path 58b and the lower back passage 36b beneath the partition 42 is checked. Therefore, the cold air coming from the evaporator 28 flows into the first cold air passage 52 without going into the second cold air passage 54. The cold air that has entered the first cold air passage 52, similarly to the embodiment shown in FIG. 1, repeats circulation for cooling the upper storage box 22, lowering the storage box 22 temperature to the preset temperature.
Next, to cool the lower storage box 24, the actuator 76 is operated to open the damper 72, as shown in FIG. 8, communicating the lower circulation path 58b with the lower back passage 36b through the opening 74a of the barrier plate 74. Therefore, the cold air coming from the evaporator 28 is branched off to flow into the first and second cold air passages 52 and 54. Then, the cold air that has flowed into the second cold air passage 54 circulates around the lower storage box 24, cooling the storage box 24 to the preset temperature. After the lower storage box 24 is cooled down to the preset temperature, the actuator 76 is controlled by the temperature sensor 70, thereby controlling the opening of the damper 72 to control the flow rate of the circulating cold air and accordingly keeping a constant storage temperature. | There is disclosed a refrigerator comprising a first passage defined in a space in the interior of a heat-insulating box to guide cold air from a evaporator downwardly, and a second passage which guides the cold air that has flowed downwardly in the first passage and rises to return to the evaporator, a partition plate which is disposed within the first passage to divide the passage into a passage which communicates the first passage with the second passage in order to allow the flow of the cold air in contact with the upper storage box, and a passage communicating with the second passage, allowing the cold air to flow into the upper storage box out of contact with the upper storage box; a regulating means which is disposed in a cold air passage from the evaporator, and regulates the flow of the cold air into the passage; and a cold air introducing means disposed in the passage. The cold air introducing means is operated to allow a part of the cold air from the evaporator to flow into the passage without being regulated by the regulating means. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to vehicle accessories for motor vehicles, and particularly to a vehicle seat cover for covering both the rear seat of a vehicle and the rear face of the front seat of the vehicle when cargo is stored in the rear seat.
2. Description of the Related Art
A wide variety of protective covers have been utilized to protect vehicle seats from damage when a load is carried in the seat. Animals are often transported in cars and SUV's, for example, and can cause considerable damage to the vehicle seats with their claws, teeth and excretory waste. Inanimate loads, such as crates with sharp edges, can also cause great damage to the vinyl or cloth of a vehicle seat. Most seat protectors include some sort of flexible sheet, usually in the form of a tarp or thick mat, as is often used in the field of furniture moving.
A simple tarp or mat, however, does not remain in place with respect to the seats and requires some sort of fastening device to hold the sheet in place. Typical covers may have a plurality of straps, hooks or the like to the hold the cover in place. However, these fasteners are rarely adjustable, making it difficult to apply the cover to multiple types of vehicle seats, and are typically not versatile, in that they cannot be connected to multiple support surfaces within the vehicle.
Further, such covers typically only cover the rear seat and the rear surface of the front seat. The interior sidewalls or interior faces of the doors are left unprotected from damage. Additionally, such covers are typically formed from a single sheet, contoured to fit inside a vehicle, but which are difficult to fold and transport.
Thus, a vehicle seat cover solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
The vehicle seat cover is a flexible sheet for covering the rear seat and the rear face of the front seat of a vehicle when a load is stored in the rear seat. If the user is transporting an animal or refuse, for example, the vehicle seat cover protects the front and rear seats from damage. The vehicle seat cover includes a base sheet, a front sheet that is releasably secured to the base sheet, and a pair of side sheets, which are also releasably secured to the base sheet. A releasable front fastener, such as a hook and loop fastener, releasably secures the front sheet to the base sheet. Similarly, a pair of side fasteners releasably secure the pair of side sheets to the base sheet.
Both the front sheet and the rear portion of the base sheet are provided with a plurality of straps and releasable connectors for securing the front sheet to the front seat and the rear portion of the base sheet to the rear seat, respectively. The straps are provided with releasable fasteners that cooperate with one another, such as quick release buckles, allowing the front straps to fasten about, for example, the headrest portions of the front seat, or about a handle mounted to the ceiling of the vehicle. The rear straps extend behind the rear seat of the vehicle to secure the base portion to the rear seat.
Further, the side sheets also have side straps secured thereto, allowing the side portions to be releasably secured to the front sheet and rear portion of the base sheet. When secured in this fashion, a five-sided protective enclosure is formed in the rear portion of the vehicle, providing protection for the inner doors or walls associated with the rear seat.
When not in use, the front sheet and the pair of side sheets may be detached from the base sheet and the sheets may be folded, secured to one another, and transported by the user.
These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an environmental, perspective view of a vehicle seat cover according to the present invention with the vehicle door open to show the interior of the vehicle.
FIG. 2 is an environmental, perspective view of the vehicle seat cover according to the present invention with the vehicle door closed as seen from the exterior of the vehicle.
FIG. 3 is a perspective view of the vehicle seat cover according to the present invention.
FIG. 4 is a partially exploded perspective view of the vehicle seat cover according to the present invention.
FIG. 5 is a partial, fragmentary perspective view of the vehicle seat cover according to the present invention, illustrating the front attachment straps of the front sheet.
FIG. 6 is a partial environmental perspective view of the vehicle seat cover according to the present invention, showing the front sheet attached to a front seat of the vehicle.
FIG. 7 is a partial environmental perspective view of the vehicle seat cover according to the present invention, illustrating user adjustment of the base sheet.
FIG. 8 is a partial environmental perspective view of the vehicle seat cover according to the present invention, illustrating attachment of the base sheet to the rear seat of the vehicle, and showing user adjustment of a pair of rear attachment straps.
FIG. 9 is a perspective view of the vehicle seat cover and storage bag according to the present invention, illustrating insertion of the folded vehicle seat cover into the bag for storage and transport when not in use.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As illustrated in FIG. 1 , the vehicle seat cover 10 covers the rear seat(s) 24 and the rear face(s) of the front seat(s) 22 of vehicle 12 , protecting the seats from damage caused by cargo, such as dog 14 , stored in the rear of vehicle 12 . Although shown as dog 14 , the cargo may be any load, such as a crate or a bag of mulch, which can damage the material of the seats through gouging, chewing, spilling or the like. The vehicle seat cover 10 is highly versatile, may be adapted for use with any suitable vehicle, and can be applied to other vehicle surfaces, such as the front seat, a truck bed, or the like.
As will be described in greater detail below, with particular reference to FIGS. 3 and 4 , the vehicle seat cover includes a base sheet 54 , having a central portion 36 and a rear portion 20 . Rear portion 20 covers the upright, upper portion of rear seat 24 , and central portion 36 covers the horizontal, lower portion of rear seat 24 . A detachable front sheet 18 covers the rear faces of front seats 22 , with the lower end of front sheet 18 being releasably secured to a front portion of base sheet 54 .
A pair of side sheets or panels 16 are further releasably secured to a pair of opposed side portions of base sheet 54 . As shown, in FIG. 1 , the far side sheet 16 is held in a substantially vertical position (to be described in greater detail below), and the near side sheet 16 is draped over the side of rear seat 24 , providing a protective covering for seat 24 when dog 14 enters or exits the vehicle. As shown in FIG. 2 , the side sheet 16 can be raised to protect the inner door or wall of vehicle 12 when door 30 is closed. The side sheet 16 may be draped over a partially open window 32 , and the height of side sheet 16 is adjustable through the adjustable closure of zippers 26 , 28 (shown in FIG. 1 ). The adjustable closure allows the user to adapt the vehicle seat cover 10 for use in a variety of vehicles having window frames 34 positioned at different heights, and for windows 32 raised to different levels. As will be described below, the side sheet 16 may be secured in a substantially vertical position to the rear portion 20 and to the front sheet 18 , allowing for usage when the window is closed (shown in FIG. 1 with regard to the far side sheet 16 ).
The side sheet 16 may be secured to the window, as will be described in greater detail below, through the use of an elastic strip 41 . Alternatively, a fastener, such as a hook and loop fastener, for example, may be secured to the side sheet 16 for engaging a complementary fastener that is permanently or temporarily secured to the window. In still another alternative, each side sheet 16 may include a pair of hooks that engage the window and maintain the side sheet 16 in place with respect to the door. Any suitable attachment element may be utilized to maintain side sheets 16 in a substantially vertical orientation in order to protect the inner door or wall of the vehicle.
Base sheet 54 , side sheets 16 and front sheet 18 are formed from canvas, heavy cloth, tarpaulin, padded material or any other suitable flexible, transportable protective material. With regard to the drawings, it should be understood that the size and contouring of base sheet 54 , side sheets 16 and front sheet 18 are dependent upon the needs and desires of the user and may be manufactured in a variety of sizes and shapes in order to be used with a variety of differing vehicles. The materials used in the construction of vehicle seat 10 are preferably non-toxic to animals, such as dog 14 .
Referring to FIGS. 3 and 4 , front sheet 18 is shown having front and rear opposed edges, with the rear edge of front sheet 18 being releasably secured to base sheet 54 . Front sheet 18 is releasably secured by hook and loop fasteners, buttons, snaps, a zipper or any other suitable releasable fastener. Positioned on opposite sides of the front edge are front straps 46 , with each front strap 46 including a fixed end and a pair of free ends. As shown in FIG. 5 , one free end may be partially secured to sheet 18 by rings 51 dimensioned to receive strap 46 slidable therethrough, depending upon the needs and desires of the user, and depending upon the particular configuration and use of the front sheet 18 . Rings 51 may have a substantially D-shaped contour in the preferred embodiment.
Each free end terminates in a female quick release buckle end 42 , which releasably engages a corresponding male quick release buckle end 40 , as will be described in further detail below. It should be understood that any suitable releasable connector elements may be substituted for quick release buckle ends 40 and 42 , depending upon the needs and desires of the user.
A pair of attachment straps 50 are further secured to the front edge of front sheet 18 , with each attachment strap 50 having a fixed end and a free end. The fixed ends of attachment straps 50 and front straps 46 are secured to the front edge by stitching or any other suitable method of secure connection. The free ends of attachment straps 50 each terminate in a male buckle connector 40 , which further acts as an adjustable buckle by threading strap 50 through adjacent loops formed in buckle end 40 , allowing the user to adjust the length of each attachment strap 50 .
A pair of fabric loops 48 are further provided and are fixed to the front edge of front sheet 18 . As shown in FIG. 5 , the user may pull the free end of a respective one of the attachment straps 50 through the loop 48 to partially secure the attachment strap 50 therethrough. As shown in FIG. 6 , when used in combination with a headrest of a vehicle, attachment strap 50 can be secured to a corresponding one of front straps 46 and loop 48 can be positioned over the headrest. Depending upon the size and configuration of the seat and headrest, the loop formed by attachment strap 50 and front strap 46 may be positioned over the headrest to secure the front sheet 18 , or additional securement may be required, which is accomplished by first inserting attachment strap 50 through loop 48 .
Alternatively, as shown in FIG. 1 , front straps 46 may be used in combination with handles mounted on the roof of the vehicle in order to secure the front sheet 18 in a substantially vertical position. Further, the front edge of front sheet 18 may be provided with two pairs of openings 49 , as shown in FIGS. 3 and 5 . In a vehicle with detachable headrests, the user may remove the headrest from the front seat and position the pair of headrest supports through openings 49 , in order to secure the front sheet 18 to the front seat.
A pair of adjustment straps 44 are also secured to the front edge of front sheet 18 , and are adapted for grasping by the user during adjustment or transportation of the cover 10 . A similar pair of adjustment straps 44 are secured to the rear portion 20 of base sheet 54 . The rear portion 20 also includes a pair of rear straps 38 , each having a fixed end and a free end terminating in a male quick release buckle connector 40 , similar to attachment straps 50 . Attachment straps 50 , rear straps 38 , adjustment straps 44 and front straps 46 are formed from nylon or any other suitable flexible, high-strength material.
Side sheets 16 are releasably joined to base sheet 54 , as shown in FIG. 4 . Similarly to front sheet 18 , the side sheets are releasably secured along their rear edges by hook and loop fasteners, zippers, buttons, snaps or any other suitable releasable fasteners. Each side sheet 16 has a pair of buckle connectors 40 , 42 mounted on opposite sides of the forward edge. Male connectors 40 each releasably engage a corresponding female connector 42 of front straps 46 , and female connectors 42 of side sheets 16 each releasably engage a corresponding male connector of rear straps 38 . As shown in FIG. 1 , this connection secures the side sheet 16 in a substantially vertical position, as shown by the far side sheet. The near side sheet 16 is free and, as described above, may be partially raised by actuation of adjustable zippers 26 , 28 . Each forward edge includes an elastic strip 41 , extending the length thereof. The elastic strips 41 allow the user to secure the side sheets 16 on a wide variety of surfaces, such as the irregularly shaped partially opened window of FIG. 2 .
As shown in FIG. 6 , an elastic strip 58 may be mounted, through stitching or any other suitable attachment method, to the front edge of front sheet 18 . Elastic strip 58 is mounted substantially centrally with respect to the front edge and aids in tightening the front sheet 18 about the front seats 22 of the vehicle 12 . Additionally, the vehicle seat cover 10 may include pockets or flaps sewn onto front sheet 18 , base sheet 54 or side flaps 16 , allowing the user to store items therein, or allowing one sheet to be stored within another sheet, e.g., a pocket or flap stitched onto base sheet 54 for storing side flaps 16 therein during transport. Additional pockets or flaps sewn onto vehicle seat cover 10 would allow for optimal versatility, portability and functionality of the vehicle seat cover.
As shown in FIG. 4 , an adjustment cord 52 is sewn into a periphery of base sheet 54 . Adjustment cord 52 may be nylon or any other suitable material, and has a user-adjustable length. As shown in FIG. 7 , the user may pull adjustment cord 52 in order to tighten rear portion 20 and central portion 56 about the rear seats 24 . Further, in positioning the vehicle seat cover 10 to a wide variety of seats and seating configurations, openings or slots may be provided in the vehicle seat cover 10 to allow for the passage of a seat belt therethrough. Different models of vehicle having differing locations for seatbelts, thus the cover may be placed between or around seatbelts on one type of vehicle, but in another, the seatbelt must pass through the material of the cover in order to maintain effective coverage. These openings or slots may be sealed through the use of zippers, buttons, or any other suitable releasable closure elements.
As shown in FIG. 8 , the rear edge of rear portion 20 is positioned over the headrests, or the tops of the seats, of rear seats 24 . Following tightening of adjustment cord 52 , the rear portion 20 may be further secured to the rear seats 24 by a pair of retaining straps 60 . Retaining straps 60 each have a fixed end secured to the lower surface of base sheet 54 , and a free end, with one end terminating in a male buckle connector 40 , and the other free end terminating in a corresponding female buckle connector 42 . The lengths of retaining straps 60 are adjustable and, when secured, allow the user to tighten the rear portion 20 about the seats 24 , with the retaining straps 60 passing around the rear of the rear seats 24 , as shown.
As illustrated in FIG. 9 , the vehicle seat cover 10 is foldable and portable. When not in use, the sheets may be folded together and secured by a pair of straps, such as, for example, attachment straps 50 . The folded vehicle seat cover 10 may be carried in a bag 62 , or in any other protective, transportable housing, depending upon the needs and desires of the user.
It should be noted that the vehicle seat cover 10 has been shown and described as covering the rear seat of a motor vehicle. It should be understood that vehicle seat cover 10 is versatile and multi-functional, and may be used to cover any suitable surface, such as a front seat or the cargo area of a sports utility vehicle, and may further be used in combination with any type of vehicle, or any surface which requires protection.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | The vehicle seat cover is a flexible sheet for covering the rear seat, and the rear face of the front seat, of a vehicle when a load is stored in the rear seat. If the user is transporting an animal or refuse, for example, the vehicle seat cover protects the front and rear seats from damage. The vehicle seat cover includes a base sheet, a front sheet that is releasably secured to the base sheet, and a pair of side sheets, which are also releasably secured to the base sheet. Both the front sheet and the rear portion of the base sheet are provided with a plurality of straps and releasable connectors for, respectively, securing the front sheet to the front seat and the rear portion of the base sheet to the rear seat. When not in use, the front sheet and the pair of side sheets may be detached from the base sheet and the sheets may be folded, secured to one another and transported by the user. | 1 |
RELATED APPLICATIONS
[0001] This application is a continuation of PCT/EP2014/072253, filed Oct. 16, 2014, which claims priority to EP 13189005.5, filed Oct. 16, 2013, both of which are hereby incorporated herein by reference in their entireties.
BACKGROUND
[0002] The invention relates to a light-directing system, in particular for sunlight, having a textile sheet material which in a light-incidence region is positionable in front of a space to be shielded or to be illuminated, or in the use state is positioned in front thereof, and has a weft-thread layer which is formed from a multiplicity of weft threads, wherein the weft threads are stretched in a substantially linear manner and delimit mesh openings of the textile fabric.
[0003] A weather-protection device having a textile fabric which forms a shield against weather influences as well as solar radiation is known from WO 2012/160115 A1, which textile fabric develops the protective functions thereof in that the warp threads and weft threads delimit elongate rectangular mesh openings, wherein the opening length is at least 10 times the opening width. It is achieved therewith that undesirable radiation and precipitation is repelled by the tight longitudinal delimitations. However, by virtue of the round thread cross-sections light reflections into the shielded region do also occur.
SUMMARY
[0004] Proceeding therefrom, this disclosure is based on the object of further improving the devices known in the prior art and of achieving a two-dimensional structure for influencing in a targeted manner incident light above all of sunlight or daylight, respectively, in a region of a building.
[0005] This disclosure proceeds from the concept of achieving a defined light-directing structure by adapting the topography of a woven fabric. Accordingly, it is proposed according to this disclosure that some or all weft threads have a non-circular thread cross-section which is delimited by a plurality of individual lateral portions or lateral areas, respectively, and said weft threads at uniform orientation of the lateral portions thereof are disposed as unidirectional threads so as to be mutually parallel. In this manner, targeted light-directing is made possible in that uniformly aligned lateral portions form an optical surface for direct (mirrored) reflection and/or refraction. As opposed to round cross-sections, ranges of incident angles which are determined by segmented thread profiles are effectively masked also with a view to multiple reflections, such that a type of “louver effect” is achievable by a thread structure. The degree of protection is thus substantially determined by the thread profile while suitable mesh openings may be kept free for viewing therethrough.
[0006] In order for the light-directing range to be optimized both in terms of capture as well as reflection, it is advantageous when the lateral portions have at least one planar or concave region.
[0007] Further improvement results from the lateral portions being mutually delimited by protrusions, clearances, or edges in the thread cross-section.
[0008] It is particularly favorable in terms of angular orientation when the non-circular weft threads have a polygonal, in particular a triangular or trilobal cross-section.
[0009] A further variant of this disclosure provides that the weft threads are disposed in weft-thread groups having thread diameters which vary in a groupwise manner, that is to say that thread diameters vary in every group, wherein the lateral portions of the weft-thread groups are uniformly oriented. By virtue of the various thread diameters in every group, said various thread diameters being repeated from one group to another, lateral portions which in relation to the group are likewise variably oriented result quasi as a sheathing end of the weft-thread group or of the repeat, respectively, such that the above-mentioned advantages are likewise achievable. The repeat forms the smallest self-repeating part of the weave, that is to say that the weft-thread groups are always placed on top of one another in the same manner.
[0010] For targeted influencing of light radiation it is advantageous when at least one side portion which faces away from the space or faces the light-incidence region is impinged as a light-directing area with incident light.
[0011] In order for effective shading to be enabled and for glare and unintended heat input to be avoided, it is advantageous when the weft-threads or weft thread groups, respectively, by way of at least one lateral portion form a reflector for reflecting incident light. Advantageously, the weft threads should run transversely to the plane of the radiation path.
[0012] Further improvement of shading while at the same time providing good viewing therethrough is achieved in that the weft threads are provided with a light-reflecting or light-absorbing coating, and/or are dyed dark.
[0013] In order for radiation regions to be influenced in particular in the case of sunlight incident from obliquely above, it is advantageous when the weft threads in a delimited angular range are uniformly coated so as to be reflective or absorbent.
[0014] Further functionality in the sense of targeted utilization of light may be achieved in that the light-directing area forms a light-permeable surface, the weft threads being transparent, such that light is directed away from the light-incidence side and thus into the space to be illuminated. On account thereof, the brightness in interior rooms may be influenced without the employment of artificial lighting.
[0015] Advantageously, the weft threads are formed from a monofilament thread material such that defined optical surfaces are achieved. In order for non-directed diffusion and thus also for glare protection to be optionally enabled, multifilament yarns may also be additionally employed.
[0016] A particularly preferable structure provides that that the textile fabric has a dual-layer thread structure of warp threads forming a warp-thread layer, and of weft threads forming a weft-thread layer which is parallel with said warp-thread layer, wherein the warp threads and the weft threads are interconnected by binder threads and the weft threads bear on a single side of the warp-thread layer.
[0017] The weft threads preferably run horizontally, the weft-thread layer extending vertically.
[0018] In order to facilitate utilization, it is advantageous when the textile fabric is mounted so as to be two-dimensional in a mounting construction or is unrollable therefrom. It may also be advantageous here when the textile fabric is embedded in a transparent support plate or in a composite structure, respectively, for example in laminated glass.
[0019] A further advantageous embodiment provides that the textile fabric is disposed or is positionable in a mounting construction on the external side of a building, in front of a building opening, the weft threads running horizontally.
[0020] In order for targeted light-directing to be enabled, it is particularly advantageous when the weft threads, on the light-incidence side thereof that faces the light-incidence region or on the external side, respectively, are free from warp threads, and said weft threads across the length thereof are thus not continuously covered by warp threads.
[0021] In order to achieve reflection or transmission which is angle-selective and thus dependent on the position of the sun, it is advantageous when the weft threads run horizontally and have a reflective area which points obliquely upward into the light-incidence region, and in that the weft threads are held so as to be mutually spaced apart, wherein the spacing is determined such that incident light from obliquely above, when above a given height-related critical angle, is reflected into the light-incidence region and, when therebelow, is passed between the weft threads through into the space that faces away from the light-incidence region.
[0022] It is particularly favorable when the spacing of the weft threads has a defined uniform value between 0.05 mm and 0.1 mm.
[0023] In order to provide a suitable transition from reflection of sunlight in the summer to permeability in winter, the height-related critical angle should be in the range between 40° and 50°.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The above-mentioned aspects of exemplary embodiments will become more apparent and will be better understood by reference to the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:
[0025] FIG. 1 shows a light-directing system having a textile fabric which is disposed in front of a building, in a schematic illustration;
[0026] FIGS. 2 and 3 show the textile fabric which is configured as a dual-layer leno-woven fabric in a partial plan view onto the weft-thread side and onto the warp-thread side;
[0027] FIG. 4 shows the textile fabric having triangular weft threads and light rays which are reflected thereon, in a fragmented vertical sectional view;
[0028] FIG. 5 shows a further embodiment, having weft-thread groups of various diameters, in an illustration corresponding to that of FIG. 4 ;
[0029] FIGS. 6 and 7 show exemplary embodiments of the textile fabric, having an angle-selective transmission of light rays, in an illustration corresponding to those of FIGS. 4 and 5 .
DETAILED DESCRIPTION
[0030] The embodiments described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following description. Rather, the embodiments are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of this disclosure.
[0031] It should be understood that the terms “horizontal” and “vertical” are generally used herein to establish positions of individual components relative to one another rather than an absolute angular position in space. Further, regardless of the reference frame, in this disclosure terms such as “vertical,” “parallel,” “horizontal,” “right angle,” “rectangular” and the like are not used to connote exact mathematical orientations or geometries, unless explicitly stated, but are instead used as terms of approximation. With this understanding, the term “vertical,” for example, certainly includes a structure that is positioned exactly 90 degrees from horizontal, but should generally be understood as meaning positioned up and down rather than side to side. Other terms used herein to connote orientation, position or shape should be similarly interpreted. Further, it should be understood that various structural terms used throughout this disclosure and claims should not receive a singular interpretation unless it is made explicit herein. By way of non-limiting example, the terms “weft thread,” “warp thread,” “fabric,” to name just a few, should be interpreted when appearing in this disclosure and claims to mean “one or more” or “at least one.” All other terms used herein should be similarly interpreted unless it is made explicit that a singular interpretation is intended.
[0032] The light-directing system 10 which is illustrated in the drawing comprises a textile fabric 12 which is disposed in a light-incidence region 13 in front of a space 14 which is to be shielded or to be illuminated, in the region of a building opening, on the external side of a building 16 . To this end, the textile fabric 12 is extendable in a web-shaped manner as a roller blind from a winding device 18 . The space 14 behind the textile fabric 12 , depending on the embodiment of the textile fabric 12 , is shaded against direct solar radiation or is illuminated therewith in a targeted manner, respectively.
[0033] As is indicated (not to scale) in FIG. 1 , the textile fabric 12 has weft threads 20 and warp threads 22 which are interconnected in a mesh-like manner. The warp threads 22 , at comparatively large mutual thread spacing, run in the vertical direction, while the horizontal weft threads 20 , while adhering to a comparatively tight mutual thread spacing, intersect the warp threads 22 at a right angle. In this manner, rectangular mesh openings 24 in the mesh-shaped textile fabric 12 , which to a certain degree allow viewing therethrough, are kept free.
[0034] As is visualized in FIGS. 2 and 3 , the textile fabric 12 has a two-dimensional dual-layer structure in which the weft threads 20 and warp threads 22 are stretched in a linear manner and in each case form a dedicated planar thread layer 26 , 28 . The two thread layers 26 , 28 in each case define a single separate plane. The weft-thread layer 26 thus on one side or on the external side, respectively, bears on the warp-thread layer 28 , wherein the warp-thread layer 28 forms exclusively the internal side of the fabric which faces the building space 14 , and the weft-thread layer 26 forms the external side of the fabric which is directed outward toward the light source or the sun, respectively.
[0035] When viewed in the direction of the surface normal of the textile fabric 12 , unobstructed mesh openings 24 which on the longitudinal side are delimited by the weft threads 20 thus result. In order for the layers to be mutually fixed, the weft threads 20 and warp threads 22 are wrapped in the manner of a leno weave by comparatively thin binder threads 30 . The binder threads 30 run along the warp threads 22 . Said binder threads 30 thereby traverse the two thread layers 26 , 28 of the warp and weft threads and encompass the external sides thereof that face away from one another.
[0036] The warp threads, weft threads, and binder threads are expediently composed of a monofilament polymer thread material, for example of PET. The thread thicknesses of the weft threads and warp threads 20 , 22 are in the range between 0.1 to 2.4 mm, while the thinner binder threads 30 have a thickness of 0.05 to 0.1 mm. In the case of non-round cross-sections, the maximum transverse dimension is determined as the thread thickness. The mesh openings 24 result from the spacings of 0.05 to 2 mm between adjacent weft threads 20 , and from the spacings of 0.6 to 5 mm between warp thread centers.
[0037] In a first embodiment the weft threads 20 have a non-circular thread cross-section and are disposed so as to be mutually parallel, having uniform orientation. Uniform orientation may be obtained in that the weft threads 20 during weft insertion are drawn off tangentially and thus without twist from a supply package and are kept tensioned.
[0038] As can best be seen from FIG. 4 , the weft threads 20 , which are triangular in the cross-section, have three planar lateral faces or lateral portions 32 , respectively, which are mutually delimited by edges 34 which converge at an acute angle. By virtue of uniform orientation, all weft threads 20 by way of one side bear on the layer of warp threads 22 , while the lateral portions 32 which are inclined away from the warp threads 22 are impingeable as a light-directing area 32 with incident sunlight 38 .
[0039] In the configuration which is visualized in FIG. 4 , the weft threads 20 as micro-louvers form a reflector to reflect incident light 38 . Here, at least the light-directing area 36 is provided with a reflective coating 40 such that light is reflected in a mirrored manner. Such a segmented coating may be produced, for example, by directed vapor deposition of a metal layer on the weft threads 20 . In the case of a reflective coating across the full area on all lateral portions, multiple reflections may also lead to reflection of the light 38 and thus to effective shading of the space 14 behind the textile fabric 12 .
[0040] In order to avoid that reflected light radiation passes through the textile fabric 12 between the threads 20 , 22 , radiation-absorbing additives may also be added to the thread material. Viewing therethrough from the inside to the outside may be improved in that the thread material is dyed dark.
[0041] The degree of reflection of the textile fabric 12 may be adjusted by way of the weft-thread density and thus by way of the thread spacings and by way of the thread diameters. In principle, zonal variation of the thread densities and thread thicknesses is also possible.
[0042] In a further variant the weft and warp threads 20 , 22 are composed of a transparent thread material, wherein incident light for targeted illumination is directed into the space 14 by partial reflection and refraction at the light-directing areas 36 . Weft threads 20 having combinations of reflective and transmissive lateral portions 32 are also conceivable, for example in order to avoid direct solar radiation onto the floor of a space 14 but to otherwise enable illumination.
[0043] In the embodiment shown in FIG. 5 , same or similar parts as have been described here above are provided with the same reference signs. The substantial difference lies in that the weft threads 20 have a circular cross-section and are disposed in weft-thread groups 42 having various thread diameters per group. This means that a plurality of weft threads 20 which differ from one another in terms of their thread diameter are grouped in every weft-thread group 42 . The weft-thread groups 42 here are uniformly oriented, wherein lateral portions 32 are defined by the sheathing end 44 of the respective weft threads 20 . As shown in FIG. 5 , the placement of the different size threads relative to one another is the same in each of the groups. Here too, an arrangement similar to that of a louver is implemented.
[0044] Shading in a desired angular range may be influenced by suitably adapting the thread diameter. The lateral portion 32 which points obliquely downward may here be determined by a common tangent on the thread cross-sections.
[0045] FIGS. 6 and 7 visualize the possibility of angle-selective shading or illumination of the space 14 depending on the position of the sun, respectively. This means that the textile fabric 12 in the case of a high position of the sun, and thus at a steep incident angle or impact angle, respectively, reflects as many of the sun rays 38 as possible. By contrast, in the case of a flat angle, as much as possible of the radiation 38 ′ is directed into the space 14 . In this manner, utilization of solar radiation that is adapted to the seasons may be achieved.
[0046] In order for this property to be implemented in the textile fabric 12 , the horizontally running weft threads 20 should have a reflection area 46 which points obliquely upward into the light-incidence region 13 . Here, the mutual spacing of the weft threads in the woven fabric is adjusted such that light which is incident from obliquely above, when above a given height-related critical angle, is reflected into the light-incidence region 13 and, when therebelow, is passed through the thread gap between the weft threads 20 , into the space 14 . Here, multiple reflections may also occur, as is visualized in FIG. 7 for the thread group 42 . There, the circumferential regions of the weft threads 20 that point obliquely upward act as a reflection area 46 for the primary angle selection, wherein by virtue of the reduction in terms of diameter the upper weft thread of each thread group is substantially selective for the return reflection into the incidence region 13 . The weft thread spacing should expediently be in the range between 0.05 mm and 0.1 mm. Adaption of the spacing may be determined by simple experiments or else by simple geometric considerations.
[0047] In principle, instead of the half-cross leno weave described for producing a planar weft-thread layer 26 , it is also possible for a structure having stretched weft threads 20 to be implemented by warp-knitted fabric (warp-knitted and Raschel-knitted), a cross-laid structure, or a woven fabric in plain weave, for example. In the case of the warp-knitted fabric, the stretched weft threads are held in a stitch. In this case, the stitch wales replace the warp thread. In the case of the cross-laid structure, thread layers are deposited unidirectionally on top of one another. The structure is then fixed by interloping and stitching. In a plain weave, substantially linear weft threads may be implemented in that the diameter of the weft in comparison to the warp threads is significantly larger and the warp-thread tension during production is kept low. In this way, only the warp-thread system undulates while the weft lies stretched between the warp threads. Weft threads which are stretched in a substantially linear manner result in all cases, wherein the deviations from linearity are minor in comparison with the thread diameter.
[0048] While exemplary embodiments have been disclosed hereinabove, the present invention is not limited to the disclosed embodiments. Instead, this application is intended to cover any variations, uses, or adaptations of this disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | This disclosure relates to a light-directing system, comprising a textile sheet material, which can be positioned in a light incidence region in front of a space and has a weft-thread layer composed of a plurality of weft threads, wherein the weft threads are extended substantially linearly and bound mesh openings of the sheet material. According to this disclosure, some or all weft threads have a non-circular thread cross-section bounded by a plurality of individual side parts and are arranged parallel to each other, the orientation of the side parts of the weft threads being uniform. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a signal processing circuit board and a liquid crystal display apparatus and particularly to a signal processing circuit board and a liquid crystal display apparatus equipped with a variable resistor which has a control knob.
2. Description of the Related Art
A signal processing circuit board has been proposed which has a variable resistor (referred to as VR hereinafter) mounted thereon for adjusting the supply potential to an optimum level. For example, such signal processing circuit boards are installed in a liquid crystal panel used as the liquid crystal display (LCD) of a notebook computer or the like.
FIG. 1A is a front view of a liquid crystal panel unit employing a conventional signal processing circuit board. FIG. 1B is a back view and FIG. 1C is a side view of the same. FIG. 1D is a cross sectional view taken along the line D—D of FIG. 1 A.
As shown in FIGS. 1A to 1 D, the liquid crystal panel unit 1 has a liquid crystal panel 2 of a rectangular plate shape mounted on a front side 1 a thereof and a (front) shield sheet 3 of a frame form exposed on the outer edge of the liquid crystal panel 2 . The liquid crystal unit 1 also has a pair of signal processing circuit boards 4 a and 4 b (two printed circuit boards) mounted along a horizontal edge and a vertical edge respectively on a back side 1 b thereof. The signal processing circuit board 4 a is designed for applying a data signal to each pixel of the liquid crystal panel 2 while the signal processing circuit board 4 b is designed for applying a horizontal scan signal to each pixel of the liquid crystal panel 2 .
As shown in FIG. 1D , the shield plate 3 is made of a frame-like metal plate having an L shape in cross section. The shield plate 3 has an upright wall 3 a thereof which extends along the outer edge of the liquid crystal panel 2 to determine an outer edge of the crystal panel unit 1 . As best shown in FIGS. 1A and 1D , the shield plate 3 has a VR adjustable aperture 5 a provided in a vertical side 3k thereof and communicated with a notch in the upright wall 3 a . As shown in FIGS. 1A , 1 B, and 1 D, the signal processing circuit board 4 a has a VR mounted extension 4 c extending from a side thereof. A VR 6 a of single-side controllable type is mounted on the mounting side of the VR mounting extension 4 c (the front side 1 a of the liquid crystal panel unit 1 ) for adjusting the supply potential to an optimum level.
As shown in FIG. 1D , a light guiding plate 7 is disposed on the back side of the liquid crystal panel 2 have a layers structure. The liquid crystal panel 2 is accommodated with the light guiding plate 7 in a frame-shaped back light chassis 8 . A light reflecting sheet 7 a is bonded to the back side of the light guiding plate 7 covering the entire surface. As the back light chassis 8 is inserted beneath the back side 3 c of the shield plate 3 , the outer edge 2 d of the liquid crystal panel 2 is protected with the shield plate 3 . There is provided a space for the VR 6 a between the outer side 8 a of the back light chassis 8 and the upright wall 3 a of the shield plate 3 .
As described, the VR 6 a of single-side controllable type is mounted with its control knob 6 b at the upper on the mounting side of the VR mounting extension 4 c which extends from the side of the signal processing circuit board 4 a.
In action, the single-side control VR 6 a of single-side (one-side) controllable type can be adjusted to a desired setting of resistance with its control knob 6 b turned by an adjusting tool, such as a screwdriver, inserted into the VR adjusting aperture 5 a in the shield plate 3 . Using the VR 6 a of single-side controllable type, the supply potential can be adjusted to an optimum level from the front side 1 a of the liquid crystal panel unit 1 .
The VR adjustment has to be conducted for each AC driven crystal panel to set the driving voltage to a desired level. If the adjustment is inadequate, the panel may exhibit flickers, burns, or other visual irregularities.
FIG. 2A is a front view of another liquid crystal panel unit employing a conventional signal processing circuit board. FIG. 2B is a back view and FIG. 2C is a side view of the same. FIG. 2D is a cross sectional view taken along the line E—E of FIG. 2 B. FIG. 2E is an enlarged view of a VR mounting extension.
As shown in FIG. 2D , the liquid crystal panel unit 9 has a VR 6 d of double-side controllable type, not single-side type 6 a , mounted thereon with its control knob 6 c exposed from the back side of the signal processing circuit board 4 a As shown in FIGS. 2B and 2D , the VR aperture 5 a provided in the shield plate 3 is replaced by a VR adjusting aperture 5 b provided in the signal processing circuit board 4 a on which the VR 6 d is mounted so that the control knob 6 c is exposed from the back side of the signal processing circuit board 4 a (opposite to the components mounting side). The other arrangement and functions of this model is identical to the liquid crystal panel unit 1 (FIG. 1 ).
In action, the VR 6 d of double-side controllable type can be adjusted to a desired setting of resistance with its control knob 6 c turned by an adjusting tool, such as a screwdriver, inserted into the VR adjusting aperture 5 b in the signal processing circuit board 4 . Using the VR 6 d of double-side controllable type, the supply potential can be adjusted to an optimum level from the back side 9 b of the liquid crystal panel unit 9 .
As the liquid crystal panel units 1 and 9 are reduced in the thickness and the peripheral marginal area, their structure holds a larger area for display hence matching the down sizing and the light weighing of notebook computers with the liquid crystal display. It is now feasible that, for example, the thickness is less than 8 mm while the effective pixel area covers substantially 90% of the entire panel surface. It is essential that since the VR 6 a or 6 b is controlled by visual manipulation with the signal processing circuit board 4 a mounted to the liquid crystal panel 2 , its control knob 6 a or 6 d is exposed from the front side 1 a or the back side 1 b of the liquid crystal panel unit 1 .
However, the VR 6 a of single-side controllable type which has a height of about 1 mm and is lower than the VR 6 d of double-side controllable type of about 1.5 mm in height is suitable for minimizing the thickness but has to have the VR adjusting aperture 5 a provided in the shield plate 3 (See FIG. 1 D).
After the signal processing circuit board 4 a is assembled with its VR mounting side (the components mounting side) to face the back side of the liquid crystal panel 2 , the VR 6 a has to be adjusted through viewing the display side of the liquid crystal panel 2 . For exposing the control knob 6 b of the VR 6 a to be adjusted, the VR 6 a is shifted to the mounting location outside the liquid crystal panel 2 or beneath the shield plate 3 before the aperture 5 a is provided in the shield plate 3 .
Also, since the distance between the back side of the liquid crystal panel 2 and the upper center side of the signal processing circuit board 4 a is smaller than 1.5 mm (which is equal to the height of the VR 6 d ), the VR 6 d of double-side controllable type is hardly located in substantially a center region of the signal processing circuit board 4 a This allows the VR 6 d of double-side controllable type to be located only beneath the shield plate 3 where there is provided a sufficient room (See FIGS. 2 B and 2 D).
As the shield plate 3 has the VR adjusting aperture 5 a provided therein, the physical strength of its metal material may be declined. Also, as the VR is located at the edge of the signal processing circuit board 4 a and the room for its installation is preserved in the limited space beneath the back side of the shield plate 3 (FIGS. 1 D and 2 D), the back light chassis 8 has to be reduced in the thickness thus declining the physical strength. This is a critical condition when the shield plate 3 of the frame-narrowed structure is minimized in the frame width to provide a generous size of the effective pixel area.
For avoiding the drilling of the shield plate 3 or the thinning of the back light chassis 8 , it is desirable to locate the VR beneath the back side of the liquid crystal panel 2 . There is no room (depth) for installation of the VR between the signal processing circuit board 4 a and the light guiding plate 7 bonded on the back side of the liquid crystal panel 2 . Preserving any room for installation of the VR between the two members involves reducing the thickness of the liquid crystal panel 2 . As the reduction of the thickness may degrade the optical characteristics the liquid crystal panel 2 , it is impossible to develop any room. The VR has to stay beneath the shield plate 3 .
Since the control knob 6 c of the VR 6 d of double-side controllable type is exposed from the back side of the signal processing circuit board 4 a it can readily be accessed by the adjusting tool without difficulty. The VR 6 a of single-side controllable type is accessed by the adjusting tool inserting deeply through the VR adjusting aperture 5 a and may be injured when being groped by the tip of the adjusting tool.
Accordingly, as the conventional liquid crystal panel units 1 and 9 are limited in the installation of the VR, they may be declined in the physical strength and injured at the VR during the assembling process.
SUMMARY OF THE INVENTION
The present invention is accomplished in view of the above mentioned problems. Therefore, an object of the present invention is to provide a signal processing circuit board and a liquid crystal display apparatus which are hardly declined in the mechanical strength while its variable resistor is not limited to one particular location for the installation but successfully inhibited from being injured during the assembling process.
In order to achieve an aspect of the present invention, a signal processing circuit board, includes a board body; a variable electronic element mounted in a mounting side of the board body, the variable electronic element having an operating member to control an output outputted from the variable electronic element in a single side of the variable electronic element; and a hole provided in the board body, and wherein the operating member is positioned in the hole such that the operating member points in the other side opposite to the mounting side of the board body.
In this case, the variable electronic element has the operating member in only the single side of the variable electronic element.
Also in this case, the variable electronic element is a variable resistor.
Further in this case, the variable electronic element is a variable capacitor.
In this case, the operating member does not project from the other side.
Also in this case, the variable electronic element is mounted through an attachment member electronically and mechanically connected to the mounting side.
Further in this case, the attachment member is a flexible printed circuit connected to the mounting side to cover the hole.
In this case, the flexible printed circuit is soldered to the mounting side in a substantially center position of one end of the flexible printed circuit and two different locations of the other end of the flexible printed circuit respectively which are equally spaced from the center position of the same.
Also in this case, the variable electronic element is floated on the flexible printed circuit.
Further in this case, the flexible printed circuit has a flexibility to protect the variable electronic element from mechanical stress.
In this case, the attachment member includes a strip on which the variable electronic element is mounted and a supporting member to attach to the mounting side.
Also in this case, the supporting member includes one of a conductive bump and a conductive pin.
Further in this case, the attachment member includes a recessed block having a recess in which the variable electronic element is mounted.
In this case, the recessed block is formed of a single board.
Also in this case, the recessed block is formed of a number of layers.
In order to achieve another aspect of the present invention, a liquid crystal display apparatus controlling method, includes: providing a liquid crystal display screen; providing a board used for the liquid crystal display screen; providing a variable electronic element mounted in a mounting side of the board, the variable electronic element having an operating member to control an output outputted from the variable electronic element in a single side of the variable electronic element; forming a hole in the board: positioning the operating member in the hole such that the operating member points in the other side opposite to the mounting side of the board, the other side being opposite to the liquid crystal display screen; displaying an image on the liquid crystal display screen; and operating the operating member through the hole from the other side while viewing the image.
In this case, the operating member does not project from the other side.
Also in this case, the variable electronic element is mounted through a flexible printed circuit electronically and mechanically connected to the mounting side.
Further in this case, the flexible printed circuit covers the hole.
In this case, the variable electronic element is floated on the flexible printed circuit.
Also in this case, the flexible printed circuit has a flexibility to protect the variable electronic element from mechanical stress when the operating member is operated such that the mechanical stress is not applied to the liquid crystal display screen.
Further in this case, the variable electronic element is provided to overlap with the liquid crystal display screen.
In order to achieve still another aspect of the present invention, a liquid crystal display apparatus, includes a signal processing circuit board; and a liquid crystal display screen electronically connected to the signal processing circuit board, an image being displayed on a displaying side of the liquid crystal display screen, and wherein the signal processing circuit board includes: a board body; a variable electronic element mounted in a mounting side of the board body, the variable electronic element having an operating member to control an output outputted from the variable electronic element in a single side of the variable electronic element; and a hole provided in the board body, and wherein the operating member is positioned in the hole such that the operating member points in the other side opposite to the mounting side of the board body, and wherein the variable electronic element is provided in a opposed side opposed to the displaying side of the liquid crystal display screen such that the operating member is exposed in the opposed side through the hole.
In this case, the variable electronic element is mounted through an attachment member electronically and mechanically connected to the mounting side.
Also in this case, the attachment member is a flexible printed circuit connected to the mounting side to cover the hole.
Further in this case, the attachment member includes a strip on which the variable electronic element is mounted and a supporting member to attach to the mounting side.
In this case, the attachment member includes a recessed block having a recess in which the variable electronic element is mounted.
According to the present invention, a variable resistor of single-side controllable type having a control knob thereof on single side is mounted on the components mounting side of a signal processing circuit board with its control knob locating in an adjusting aperture provided in the signal processing circuit board to open at the components mounting side and simultaneously facing in a direction opposite to the components mounting side. This allows the variable resistor installed in a liquid crystal display panel of a thin, frame-narrowed structure to be mounted at a proper location without unnecessary limitation and protected from being injured during the assembling process without declining the mechanical strength.
A liquid crystal display apparatus of the present invention can be implemented using the signal processing circuit board described above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a front view showing a liquid crystal panel unit employing a conventional signal processing circuit board;
FIG. 1B is a back view showing the liquid crystal panel unit employing the conventional signal processing circuit board;
FIG. 1C is a side view showing the liquid crystal panel unit employing the conventional signal processing circuit board;
FIG. 1D is a cross sectional view taken along the line D—D of FIG. 1A ;
FIG. 2A is a front view showing a liquid crystal panel unit employing another conventional signal processing circuit board;
FIG. 2B is a back view showing the liquid crystal panel unit employing the another conventional signal processing circuit board;
FIG. 2C is a side view showing the liquid crystal panel unit employing the another conventional signal processing circuit board;
FIG. 2D is a cross sectional view taken along the line E—E of FIG. 2A ;
FIG. 2E is an enlarged view of a VR mounting region shown in FIG. 2A ;
FIG. 3A is a front view showing a liquid crystal panel unit employing a signal processing circuit board according to an embodiment of the present invention;
FIG. 3B is a back view showing the liquid crystal panel unit employing the signal processing circuit board according to the embodiment of the present invention;
FIG. 3C is a side view showing the liquid crystal panel unit employing the signal processing circuit board according to the embodiment of the present invention;
FIG. 4 is an exploded view of a liquid; crystal display module including the liquid crystal panel unit shown in FIGS. 3A to 3 C;
FIG. 5 is a longitudinally cross sectional view showing an internal arrangement of the liquid crystal display module shown in FIG. 4 ;
FIG. 6A is a plan view showing a portion of the components mounting side of the signal processing circuit board of the embodiment on which a VR is mounted;
FIG. 6B is a cross sectional view taken along the line A—A of FIG. 6A ;
FIG. 6C is a plan view showing a portion of the back side of the signal processing circuit board of the embodiment on which the VR is mounted;
FIG. 7A is a cross sectional view explaining a step for mounting the VR on the signal processing circuit board shown in FIGS. 6A to 6 C;
FIG. 7B is a cross sectional view explaining another step for mounting the VR on the signal processing circuit board shown in FIGS. 6A to 6 C;
FIG. 7C is a cross sectional view explaining a further step for mounting the VR on the signal processing circuit board shown in FIGS. 6A to 6 C;
FIG. 7D is a cross sectional view explaining a still further step for mounting the VR on the signal processing circuit board shown in FIGS. 6A to 6 C;
FIG. 7E is a cross sectional view explaining a still further step for mounting the VR on the signal processing circuit board shown in FIGS. 6A to 6 C;
FIG. 8A is a plan view showing a portion of the components mounting side of the signal processing circuit board of the embodiment on which the VR is mounted with modifications;
FIG. 8B is a cross sectional view taken along the line B—B of FIG. 8A showing one modification;
FIG. 8C is a cross sectional view taken along the line B—B of FIG. 8A showing another modification;
FIG. 8D is a plan view showing a portion of the back side of the signal processing circuit board of the embodiment on which the VR is mounted with the modifications:
FIG. 9A is an overall perspective view of a recessed block showing a still further modification;
FIG. 9B is an overall perspective view of another form of the recessed block showing a still further modification;
FIG. 9C is a cross sectional view showing the VR mounted on the recessed block of the still further modification;
FIG. 9D is a cross sectional view showing the VR mounted on the another form of the recessed block of the still further modification;
FIG. 10A is a plan view showing a portion of the components mounting side of the signal processing circuit board of the embodiment on which the VR is mounted by the recessed block shown in FIGS. 9A to 9 D;
FIG. 10B is a cross sectional view taken along the line C—C of FIG. 10A ; and
FIG. 10C is a plan view showing a portion of the back side of the signal processing circuit board of the embodiment on which the VR is mounted by the recessed block shown in FIGS. 9A to 9 D.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will be described referring to the relevant drawings.
FIG. 3A is a front view of a liquid crystal panel unit including a signal processing circuit board according to an embodiment of the present invention. FIG. 3B is a back view and FIG. 3C is a side view of the same.
As shown in FIGS. 3A and 3B , the liquid crystal (LC) panel unit 10 has a liquid crystal panel 11 of a rectangular shape and a (front) shield plate 12 of a frame-like shape on the outer edge of the liquid crystal panel 11 to be exposed in a front side 10 a of the liquid crystal panel unit 10 . The liquid crystal panel unit 10 includes a pair of signal processing circuit boards (two printed circuit boards of a source circuit board and a gate circuit board) 13 and 14 mounted on a back side 10 b thereof along a horizontal side and a vertical side respectively.
As the liquid crystal panel unit 10 is reduced in the thickness and the peripheral marginal area, their structure holds a larger area for display hence matching the down sizing and the light weighing of a notebook computer with the liquid crystal display. Preferably, the liquid crystal panel unit 10 may be 4 to 8 mm in the thickness and its effective pixel area may be about 90% of the entire panel surface.
The shield plate 12 is made of a frame-like shaped metal material having an L shape in cross section. The shield plate 12 has an upright wall 12 a thereof which extends along the outer edge of the liquid crystal panel 11 to determine an outer edge of the crystal panel unit 10 . A variable resistor (VR) 15 of single-side controllable type is mounted on a components mounting side of the signal processing circuit board 13 with its control knob exposed from the back side of the same.
The VR 15 is joined by a flexible printed circuit (FPC) 16 to the signal processing circuit board 13 and its control knob is exposed from the back side 10 b of the liquid crystal panel unit 10 . The VR 15 can hence be adjusted to a desired level of resistance by an adjusting tool, such as a screwdriver, engaging and turning its control knob.
FIG. 4 is an exploded view of a liquid crystal module including the liquid crystal panel shown in FIGS. 3A to 3 C. As shown in FIG. 4 , the liquid crystal module 17 consists mainly of the liquid crystal panel 10 , the shield plate 12 , and a back light unit 18 . The liquid crystal panel unit 10 is sandwiched from both sides between the shield plate 12 and the back light unit 18 and assembled together, to form the liquid crystal module 17 .
The paired signal processing circuit boards 13 and 14 are mounted along a long edge and a short edge respectively on the liquid crystal panel 11 of the liquid crystal panel unit 10 . A plurality of tape carrier packages (TCPs) 19 of driver integral circuits (IC) are provided to one of long sides of the signal processing circuit board 13 along the long side. Similarly, a plurality of tape carrier packages (TCPs) 20 of driver integral circuits (IC) are provided to one of long sides of the signal processing circuit board 14 along the long side.
The TCP 19 and the TCP 20 join the signal processing circuit boards 13 and 14 respectively to the liquid crystal panel 11 . Accordingly, the two signal processing circuit boards 13 and 14 can be folded down onto the back side of the liquid crystal panel 11 at their respective TCPs 19 and 20 (See FIG. 3 B).
The back light unit 18 includes a light guiding plate 22 , a light diffusing sheet 23 , a light reflecting sheet 29 , and a back light module 24 joined to one another to have a rectangular unit (FIG. 5 ). A lamp (not shown) is installed in a lowermost region of the light guiding plate 22 . A lamp cable 25 extends from one end of the lowermost region which is connected at a distal end with a connector 25 a . The light guiding plate 22 , the light diffusing sheet 23 , and the light reflecting sheet 29 are bonded in layer relationship and fixedly joined at the outer edge with the back light module 24 .
FIG. 5 is a longitudinal cross sectional view showing an internal arrangement of the liquid crystal module 17 . As shown in FIG. 5 , the liquid crystal module 17 has a layer arrangement where placed one over the other in an order, from the liquid crystal display screen or the front side 10 a of the liquid crystal panel unit 10 to the signal processing circuit board 13 , are the liquid crystal panel 11 which includes four layers of a polarizing plate 26 a , an opposite substrate 27 , a thin film transistor (TFT) substrate 28 , and another polarizing plate 26 b , the light guiding plate 22 , the light reflecting sheet 29 , and the signal processing circuit board 13 .
The signal processing circuit board 13 includes the VR 15 , a variable capacitor, a resistor, a capacitor and other circuitry components which are not shown in FIG. 5 , in addition to the driver IC, resistors, and capacitors and the like.
The liquid crystal module 17 is protected at the outer edge with the shield plate 12 extending over the back light mold 24 . A lamp 30 is provided along the lowermost part 22 b of the light guiding plate 22 . The light guiding plate 22 is arranged of a tapered cross section which becomes gradually thicker from the upper end to the lower end. The back side of the light guiding plate 22 is spaced by a small gap 40 from the signal processing circuit board 13 . The small gap 40 is developed and maintained by the thickness of the back light mold 24 provided above for accepting some components.
The TCP 19 mounted at the uppermost of the signal processing circuit board 13 has a front end 19 a thereof extending in an arc-shape and along the outer edge of the back light mold 24 and connected with the TFT substrate 28 of the liquid crystal panel 11 .
FIG. 6A is a plan view showing a portion of the components mounting side 13 a of the signal processing substrate 13 on which the VR 15 is mounted. FIG. 6B is a cross sectional view taken along the line A—A of FIG. 6 A. FIG. 6C is a plan view showing a portion of the back side 13 b of the signal processing circuit board 13 on which the VR 15 is mounted.
As shown in FIGS. 6A to 6 C, the VR 15 is mounted at a particular location on the components mounting side 13 a of the signal processing circuit board 13 which thus has a VR adjusting opening 31 (e.g. of a rectangular shape) provided therein for access to the VR 15 .
The VR adjusting opening 31 is shaped to a minimum size suited for avoiding the VR 15 from being damaged by the adjusting tool during the adjusting process and allowing its control knob 15 a to be manipulated by the adjusting tool without difficulty while being free from the signal processing circuit board 13 (See FIGS. 6 B and 6 C). The size of the VR adjusting opening 31 may be equal to a sum of the size of the control knob 15 a of the VR 15 and a discrepancy from of the installable area of the VR 15 .
The VR 15 is not directly joined to the signal processing circuit board 13 but mounted on the FPC 16 , which exhibits a level of flexibility against the applied stress as is spaced above from the signal processing circuit board 13 (FIG. 6 B). The control knob 15 a of the VR 15 faces the VR adjusting opening 31 and points in the direction of the back side 13 b of the signal processing circuit board 13 opposite to the components mounting side 13 a (FIGS. 6 B and 6 C).
The FPC 16 has a rectangular shape which is greater in the size than the mounting side 15 b facing opposite to the control knob 15 a of the VR 15 . The VR 15 is fixedly joined at its mounting side 15 a to substantially the center of the FPC 16 . The FPC 16 is in turn joined to the components mounting side 13 a of the signal processing circuit board 13 so as to shut off the VR adjusting opening 31 entirely. More particularly, the FPC 16 carrying the VR 15 is soldered at its edge to the components mounting side 13 a of the signal processing circuit board 13 by three VR terminal soldering sections 32 a , 32 b , and 32 c which are connected to connection terminals 15 c of the VR 15 respectively (FIGS. 6 A and 6 B).
The VR terminal soldering section 32 a is located at substantially the center of one end of the FPC 16 while the other two VR terminal solders 32 b and 32 c are located at two different locations of the other end of the FPC 16 respectively which are equally spaced from the center of the same.
As shown in FIG. 6B , when the FPC 16 is soldered by the VR terminal solders 32 a , 32 b , and 32 c to the components mounting side 13 a of the signal processing circuit board 13 , the FPC 16 is formed such that the control knob 15 a of the VR 15 is supported so as not to project from the VR adjusting opening 31 in the direction of the back side 13 b.
More specifically, the FPC 16 bent to a predetermined shape by forming process holds the VR 15 in the VR adjusting opening 31 so that its control knob 15 a is flush with the back side 13 b of the signal processing circuit board 13 . The FPC 16 may preferably be made of a sheet material which can easily be shaped by any known forming process.
The function of the FPC 16 hence includes electrical and mechanical connection of the VR 15 to the signal processing circuit boards 13 , leveling the VR 15 with the signal processing circuit board 13 , and serving as a resistor mounting member, hence contributing to the minimum thickness of the liquid panel unit 10 on which the signal processing circuit board 13 is mounted and thus of the liquid crystal display.
FIGS. 7A to 7 E are cross sectional views explaining a procedure of mounting the VR onto the signal processing circuit board shown in FIGS. 6A to 6 C. Referring to FIGS. 7A to 7 C, the VR 15 is first mounted on the FPC 16 ( FIG. 7A ) with its mounting side 15 b down (FIG. 7 B). Then, both ends of the FPC 16 are lightly bent until they tilts downwardly at an angle (FIG. 7 C).
The FPC 16 is then subjected to the forming process where its two regions on both sides of the VR 15 are curved upwardly, leaving the two ends leveled with the VR 15 (FIG. 7 D). The formed FPC 16 is supported beneath the signal processing circuit board 13 with the control knob 15 a of the VR 15 positioned just in the VR adjusting opening 31 and soldered at both ends to the components mounting side 13 a of the signal processing circuit board 13 . The mounting of the FPC 16 on the signal processing circuit board 13 is now completed.
During the forming process of the FPC 16 , care should be taken so that the control knob 15 a of the VR 15 mounted thereon stays in the VR adjusting opening 31 but not projects upwardly from the back side 13 b of the signal processing circuit board 13 .
As described above, the FPC 16 mounted to the signal processing circuit board 13 allows the control knob 15 a of the VR 15 to be exposed at the VR adjusting opening 31 from the back side, opposite to the display side, of the liquid crystal module 17 . The control knob 15 a can easily be accessed and controlled by an adjusting tool, such as a screwdriver, inserting from the back side of the liquid crystal module 17 into the VR adjusting opening 31 . More particularly, the VR 15 can be adjusted to a desired level of resistance with the adjusting tool for determining the optimum supply potential while observing the display of the liquid crystal module 17 .
Also, the FPC 16 is selected from flexible materials of a thickness which can be bent in a short stroke for inhibiting declination of the efficiency of the mounting process and can bear a stress (of pressure and turning) during the VR adjustment while the VR 15 is of single-side controllable type.
The VR 15 of single-side controllable type which is lower in the height is mounted on the FPC 16 and located in the VR adjusting opening 31 provided in the signal processing circuit board 13 of the liquid crystal panel 11 in the liquid crystal display. This permits the VR 15 to be accessed and controlled from the back side opposite to the components mounting side of the signal processing circuit board 13 or the back side of the liquid crystal display for adjusting the supply potential to an optimum level.
Also, as the VR 15 is mounted on the FPC 16 , it can be protected from being intensively stressed during the adjustment of resistance of the VR 15 by the flexibility of the FPC 16 . While the VR 15 is inhibited from being injured, the direct transmission of stress to the back light unit 18 can favorably be avoided and the performance of the liquid crystal display will be ensured without declining its image quality.
The VR 15 is mounted as overlapped with the liquid crystal panel 11 and its installation is not limited by the back light chassis (See FIGS. 1 D and 2 D). Since the VR 15 is enabled to sit at any location where its room or space is provided, the freedom for designing the signal processing circuit board 13 can significantly be increased.
The signal processing circuit board on which the VR 15 is mounted with some modifications will now be described referring to FIGS. 8A to 8 D.
FIG. 8A is a plan view showing a portion of the components mounting side of the signal processing circuit board on which the VR is mounted with the some modifications. FIG. 8B is a cross sectional view taken along the line B—B of FIG. 8A showing one modification. FIG. 8C is a cross sectional view taken along the line B—B of FIG. 8A showing another modification. FIG. 8D is a plan view showing a portion of the back side of the signal processing circuit board.
As shown in FIGS. 8A to 8 D, this arrangement and function is identical to that shown in FIGS. 6A to 6 C, except that the VR 15 is mounted to the signal processing circuit board 13 by a combination of a board 33 and supporting member 34 which replace the FPC 16 .
The board 33 may be made of the same material as of the signal processing circuit board 13 . The board 33 on which the VR 15 is mounted at its mounting side 15 b is joined to the components mounting side 13 a of the signal processing circuit board 13 by the pillar- or wall-like supporting member 34 which are arranged of, for example, a bump 34 a ( FIG. 8B ) or a pin 34 b ( FIG. 8C ) made of a conductive material. The supporting member 34 of the bump 34 a are directly solder to or the supporting member 34 of the pin 34 b are soldered by VR terminal solders 32 a , 32 b , and 32 c to the components mounting side 13 a.
The signal processing circuit board on which the VR 15 is mounted with further modifications will be described referring to FIGS. 9A to 9 D.
FIG. 9A is an overall perspective view of a recessed block showing one modification. FIG. 9B is an overall perspective view of another form of the recessed block. FIG. 9C is a cross sectional view of the VR mounted on the recessed block. FIG. 9 d is a cross sectional view of the VR mounted on the another form of the recessed block. As shown in FIGS. 9A to 9 D, this arrangement and function is identical to that shown in FIGS. 6A to 6 C, except that the VR 15 is mounted on the signal processing circuit board 13 by the concave-type board 35 which replaces the FPC 16 .
The concave-type board 35 may be made of the same material as of the signal processing circuit board 13 . The concave-type board 35 has a (installation) concave section 35 a provided in the center thereof for installation of the VR 15 and three vertical flutes 36 provided in both sides thereof for electrical and mechanical connection with the signal processing circuit board 13 (FIG. 9 A). The concave section 35 a may be replaced by a slot section 35 b with a pair of opposite side walls eliminated (FIG. 9 B). The number of the vertical flutes 36 is not limited to three but may be more if desired. The concave-type board 35 may be formed of a single board or a number of layers.
Before mounting the VR 15 on the concave-type board 35 , a conductive pattern 37 is provided on the bottom of the concave section 35 a for connecting connection terminals 15 c of the VR 15 to the components mounting side 13 a of the signal processing circuit board 13 (FIG. 9 C). The conductive pattern 37 may be provided on the back side of the concave-type board 35 as extended from the concave section 35 a (FIG. 9 D).
FIG. 10A is a plan view showing a portion of the components mounting side of the signal processing circuit board 13 where the VR 15 is mounted by the recessed block shown in FIGS. 9A to 9 D. FIG. 10B is a cross sectional view taken along the line C—C of FIG. 10 A. FIG. 10C is a plan view showing a portion of the back side of the signal processing circuit board 13 where the VR 15 is mounted by the recessed block shown in FIGS. 9A to 9 D.
As shown in FIGS. 10A to 10 C, the concave-type board 35 is joined at its vertical flutes 36 by soldering to the signal processing circuit board 13 .
According to the embodiments, the VF 15 of single-side controllable type which is shorter in the height than the double-side controllable type and lower in price is enabled to sit on the signal processing circuit board 13 of the liquid crystal panel 11 of a liquid crystal display, such as a notebook computer, having basically a thin, frame-narrowed arrangement and can favorably be adjusted while observing the display.
Also, as the VR 15 is mounted by the FPC 16 to the signal processing circuit board 13 , it can be protected from being intensively stressed during the adjustment of resistance by the flexibility of the FPC 16 which also dissipates the stress to the signal processing circuit board 13 . This will minimize the injury of the VR 15 and the fracture of the FPC 16 . As the VR 15 of single-side controllable type is low in the height and its control knob 15 a stays in the VR adjusting opening 31 provided in the signal processing circuit board 13 but not exceeding the thickness of the board (FIG. 6 B), the installation of the VR can be decreased in the overall height.
Since the height of the VR which is a major target to be tackled for minimizing the overall thickness and implementing the frame-narrowed structure is decreased, such tall, troubled components are eliminated and the minimizing the overall thickness and the implementing the frame-narrowed arrangement can be accelerated. The VR 15 on the signal processing circuit board 13 remains not projected outwardly of the back side of the board (FIG. 6 B), hence preventing any event of injury by the physical collision or short-circuit by the electrical contact at the back side of the signal processing circuit board 13 during the assembling process of the liquid crystal panel unit 10 at either the manufacturer's plant or the client's workshop.
While being free from preparing a particularly raised VR mounting area off the shield plate 3 or at an edge region thereof so that the VR 15 does not overlap the liquid crystal panel 11 , the signal processing circuit board 13 is arranged of a simple rectangular shape without extensions thus decreasing the margin of a material and contributing to the cost down of the overall assembly.
This allows the liquid crystal display to be minimized in the height of components mounted on the signal processing circuit board 13 while its effective area in the overall display surface remaining wide and its structure remaining narrow in the marginal area, hence decreasing the overall thickness and the cost of production. Also, the adjustment on the VR can be manipulated from the back side of the signal processing circuit board 13 or of the liquid crystal display. As the control knob 15 a of the VR 15 is highly visible and accessible in the VR adjusting opening 31 , its adjusting action can be improved in the efficiency. In particular, when different types or sizes of the display are flexibly manufactured on a single production line, the above mentioned advantage will be more emphasized.
The use of the FPC 16 is also advantageous. This permits the bump 34 a which may hardly be controlled in the size along the vertical direction to be favorably employed under appropriate control. If the pin 34 b is selected, any conventional manner requires three consecutive steps for mounting the VR 15 to the board 33 , mounting the pins 34 b to the board 33 , and mounting the pins 34 b to the signal processing circuit board 13 . Using the FPC 16 , the procedure may duly be replaced by two steps or mounting the VR 15 to the FPC 16 and mounting the FPC 16 to the signal processing circuit board 13 .
When the concave-type board 35 is used, its fabrication is not an easy task and requires steps of seat preparation and bonding multiple layers to form a layer structure. The FPC 16 can readily be fabricated by punching process. The FPC 16 is flexible enough as compared with the bumps 34 a the pins 34 b , and the concave-type board 35 and can hardly be fractured because it absorbs a force of impact developed by the adjusting too.
The mounting of the component on the signal processing circuit board 13 is not limited to the VR 15 but any other similar component, such as a variable capacitor of single-side controllable type, may successfully be mounted on the signal processing circuit board 13 by the foregoing manner.
While the VR 15 is mounted on the signal processing circuit board 13 throughout the embodiments, it may be mounted on the signal processing circuit board 14 or another substrate (not shown) for controlling different voltages which are applied for operating the liquid crystal display.
As set forth above, the present invention allows the variable resistor of single-side controllable type having a control knob thereof on single side to be mounted on the components mounting side of the signal processing circuit board with its control knob locating in the adjusting aperture provided in the signal processing circuit board to open at the components mounting side and simultaneously facing in a direction opposite to the components mounting side. Accordingly, the variable resistor installed in a liquid crystal display panel of a thin, frame-narrowed structure can favorably be mounted at a proper location without unnecessary limitation and protected from being injured during the assembling process without declining the mechanical strength because the shield plate and the chassis have not openings nor notches.
The liquid crystal display apparatus of the present invention can be implemented using the signal processing circuit board described above. | A signal processing circuit board includes a board body, a variable electronic element, and a hole. The variable electronic element is mounted in a mounting side of the board body. The variable electronic element has an operating member to control an output outputted from the variable electronic element in a single side of the variable electronic element. The hole is provided in the board body. The operating member is positioned in the hole such that the operating member points in the other side opposite to the mounting side of the board body. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an electric fuse having a housing which encases a fuse element located in a chamber. The fuse element melts and thus cuts out the fuse under an overcharge, whereby the temperature and pressure in the interior of the chamber will abruptly rise.
If the pressure developed in the chamber on cutting out a fuse exceeds a given limit, the housing is destroyed in an explosion-like manner. If the housing e.g. comprises a base and a cap, which engages over the base and is fixed thereto to form the chamber, the cap is blown off the base if the internal pressure of the chamber rises beyond a given limit. The switching or breaking capacity of a fuse is decisively dependent on the internal pressure of the chamber which occurs on reaching a corresponding cutout current and which can be sustained by the housing without a destruction risk.
2. Prior Art
Numerous different measures are known for preventing or at least delaying the rapid rise of the chamber internal pressure on cutting out the fuse, so as to increase the switching capacity of the latter. These measures can only be carried out on a limited number of fuse types and also only allow a limited increase in the fuse switching capacity.
OBJECT OF THE INVENTION
The object of the invention is therefore to increase the switching capacity of electric fuses of the aforementioned type in a simple, reliable and inexpensive manner.
SUMMARY OF THE INVENTION
According to the invention this object is met in that the housing is provided with pressure relief means for relieving pressure created within said fuse chamber by the expansion of gases when the fuse element opens.
Therefore the invention adopts a new procedure, in that a destruction of the housing, if high internal pressure peak values occur on cutting out the fuse, is prevented by leading off at least part of the gas volume to the outside from the fuse chamber, namely by means of a pressure relief means. The total tightness of the fuse chamber is abruptly given up by the pressure relief means, so that the gas pressure immediately drastically drops and part of the gas volume is discharged to the outside. This measure is preferable to an uncontrolled destruction of the fuse in the case of very high cutout currents.
In principle, there are two alternatives for the design of the pressure relief means.
In the first alternative, according to the invention at least one opening in the fuse element chamber forms the pressure relief means in such a way that on cutting out the fuse an adequate gas volume proportion can escape to the outside through the opening. The opening is located in the chamber where it is possible to accept an escape of a proportion of the gas volume. From the outset the fuse element chamber has one or more openings, which ensure an adequate internal pressure limitation of the fuse in the case of a high cutout current.
In the second alternative, according to the invention by the pressure rise in the casing occuring on cutting out the fuse, at least one opening in the chamber is freed for forming the pressure relief means in such a way that on cutting out the fuse an adequate gas volume porportion can escape to the outside through the opening. According to this solution, the fuse has a fuse element chamber closed in pressure-tight manner, but in which by means of predetermined rupture location it is ensured that if harmful pressure peak values occur openings form in the casing at the predetermined rupture location and through them there can be an adequate gas volume escape to the outside for the pressure relief of the fuse element chamber.
To prevent the gas flow passing out of the opening from striking adjacent components or the like, according to a further development of the invention the opening is faced by a baffle element, e.g. a baffle plate in such a way that the outflowing gases are deflected and also cooled. When the gases flow out, the deflection keeps the said gases initially in the vicinity of the fuse.
On the inside the opening or the openings are preferably covered by an element, e.g. by a ceramic paper insert or a foil, which acts as a filter, cooling medium and valve or flow resistor when the gas flows out. This in particular also prevents metal vapours, which can form when the fuse element melts, from passing in unimpeded manner into the vicinity of the fuse.
For the version in which openings in the chamber only form when pressure peak values occur, according to the invention the openings in the casing wall are in the form of recesses, whose thin-walled closure can be blown off by the gas pressure on cutting out the fuse.
Another version of the inventive fuse is characterized in that the openings, which form in the manner of pressure relief means in the case of high compressive loads, on cutting out the fuse, are formed by housing expansions more particularly between ribs and locking grooves of housing parts interconnected by such locking elements, the housing parts having different expansion characteristics. The latter is based on the design and e.g. occurs where a fuse, such as a miniature fuse, comprises a base, over which engages a cap and which is fixed to said base. When high pressures occur, the cap wall at this point is subject to a much higher expansion as compared with the relatively solid base.
According to a further development of the invention, the housing encasing the fuse element chamber has a relief chamber on the side of the openings. Here again the openings are covered by a corresponding element on the way from the main chamber to the relief chamber, e.g. by a ceramic paper insert or foil, whose action has been explained hereinbefore. In the case of peak pressure stresses in the fuse element chamber, part of the gas volume can pass via the openings into the relief chamber, which brings about a cooling of said gas volume and therefore a corresponding pressure relief.
The invention is particularly suitable for miniature fuses, in which the gas volume enclosed in the fuse element chamber is particularly small and is therefore suddenly heated by the heat released as a result of the melting of the fuse element and is consequently subject to a corresponding pressure rise. Thus, an advantageous further development or use of the invention is characterized in that, in known manner, the housing comprises a base and a cap, which form a chamber, in which are arranged pins carrying the fuse element and that the opening or the openings which form in the case of an overload are located in the fuse cap. The relatively thin-walled cap is suitable for the production of such openings and the space in the vicinity of the fuse into which the gas volume parts can flow, is generally positioned above the fuse or laterally thereof.
Another development of the invention comprises a rectangular shape of the housing formed by the base and the cap, which engages over the base and which has as fastening elements, e.g. snapping elements. This kind of a miniature fuse is of particular interest, because the smaller end faces in the case of a rapid pressure rise within the chamber are subject to a smaller bulging than the larger lateral faces. In the case of a locking fastening between the cap and base by means of ribs and locking grooves on the smaller end faces, on reaching or exceeding specific internal pressure peak values as a result of the different bulging or curvature of the end and lateral faces an opening gap can form between the lateral faces and the corresponding opposite faces of the base through which a gas volume proportion can escape. As a result of the high pressure load on the long lateral faces of the cap correspondingly high pulling forces act on the end faces of the cap, so that the latter, with the two end faces, at the instant of reaching very high internal pressure values is pressed very firmly onto the corresponding frontal opposite faces of the base and therefore onto the locking ribs located there. The greater rigidity of the end faces of the cap contributes to the varying bulging of the end faces and the lateral faces.
According to an advantageous further development of the above described design only the end faces of the cap and the corresponding frontal opposite faces of the base are interconnected, more particularly by a locking fastening. This facilitates the formation of an opening gap on the long rectangular sides. The cooling of the escaping gas proportion on the gap walls can be enhanced by the insertion of cooling elements.
It is possible for the cross-sectionally round or angular cap to have an opening on its side facing away from the base which can be closed by a cover to be fastened with locking elements as a pressure relief means. Thus, in the case of an overpressure, relief openings form on the top of the fuse housing, namely between the locking elements, by means of which the cover is fixed to the cap.
BRIEF DESCRIPTION OF THE DRAWINGS
Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings, which by way of illustration schematically show prefered embodiments of the present invention and the principles thereof and what now are considered to be the best modes contemplated for applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the scope of the appended claims.
Embodiments of the invention are described in greater detail hereinafter relative to the accompanying drawings, wherein show:
FIG. 1 a cross-sectional view of a miniature fuse with openings forming a pressure relief means in a cap of said fuse.
FIG. 2 a cross-sectional view of a miniature fuse, whose fuse element chamber is connected by means of openings to a relief chamber.
FIG. 3 a cross-sectional view of a miniature fuse with an opening in the fuse cap and with a baffle plate.
FIG. 4 a cross-sectional view of a miniature fuse with a pressure relief means in the form of openings, which form on pre-established thin-walled recesses of the fuse cap in the case of an overload.
FIGS. 5 and 6 cross-sectional representations of a locking connection formed by ribs and locking grooves without and with pressure relief.
FIG. 7 a diagrammatic perspective view of a miniature fuse with a rectangular cross-section.
FIG. 8 a cross-sectional view of a miniature fuse with a cap closable by a cover.
FIG. 9 a cross-sectional view of a miniature fuse with a rectangular cross-section with a cap expanded under the influence of a very high internal pressure.
FIG. 10 a cross-sectional view relative to FIG. 9 with the sectional plane displaced by 90°.
DETAILED DESCRIPTION OF THE EMBODIMENTS
In the embodiment of FIG. 1, a miniature fuse housing 1 comprises two plastic parts, namely a base 2 and a cap 3, which together with the base 2 forms a chamber 7 and to which is fixed the base 2 in the represented position, e.g. by a bond and/or a locking connection. In known manner the base 2 is traversed by two, spaced, metallic connecting pins 4 and on the upper ends 5 of said pins 4 a fuse element 6 is fixed in the chamber 7 in an appropriate manner, e.g. by soldering or welding.
As shown, on the top of the cap 3 there are several openings 8, which are closed on the inside by a ceramic paper insert 9 or by a thin foil. As explained hereinbefore, the openings 8 serve to relieve the casing when pressure peak values occur and which are obtained on cutting out the fuse, namely when the fuse element 6 melts. In this case part of the gas volume can escape to the outside from the chamber 7 through the insert 9 and the openings 8. The insert 9 acts as a cooling medium and filter or valve, which is positioned upstream of the openings 8 and has an energy absorbing function in conjunction with a filtering and cooling function.
In the second embodiment according to FIG. 2, whose fundamental construction of a miniature fuse has the same reference numerals for the same parts as in FIG. 1, unlike in the embodiment of FIG. 1, the top of the cap 3 is provided with a relief chamber 10. For relieving the chamber 7 when internal pressure peak values occur, part of the gas volume can pass from the chamber 7, through the insert 9 and the openings 8 into the relief chamber 10. As a function of the pressure peak value reached, the relief effect here is less than in the case of the embodiment of FIG. 1, because the volume and therefore the absorption capacity of the relief chamber 10 can only be relatively small. The cooling action and energy absorption are of the same order of magnitude. The main advantage of this embodiment is that the gas-tightly sealed nature of the casing 1 with respect to the environment is also maintained in the case of peak loads, so that no gases flow out.
Also in the case of the miniature fuse shown in FIG. 3 the basic construction is the same as for the embodiments of FIGS. 1 and 2. The essential difference is that on the top of the miniature fuse cap 3 is provided a central opening 8, which is faced in spaced manner by a baffle element 11. Thus, outflowing gases, as indicated by the arrows in the drawing, are deflected between the surface 12 of the cap 3 and the baffle element 11, constituted by a baffle plate here, and are led away laterally, which leads to a cooling action. The baffle element 11 can be fixed in any manner spaced above the surface 12 the cap 3, e.g. by support elements 13 constructed in one piece with the baffle element 11 and which are bonded to the surface 12 of the cap 3 and which form an adequate passage for the outflowing gases. The support element can also be constituted e.g. by a ring with corresponding laterally directed recesses or openings.
The miniature fuse embodiment shown in FIG. 4 has, unlike the three previously described embodiments, no openings in the housing 1 and in this case, as shown in FIG. 4, openings 8' as relief openings only form when internal pressure peak values are reached, which threaten to blow up the housing 1. For this purpose are provided at certain points, namely on the top of the cap 3 in the casing wall thereof a number of recesses 14, which form corresponding thin-walled predetermined breaking points and on exceeding predetermined internal pressure values can be fractured for forming openings 8'. Here again, it is additionally possible to use an insert, as shown in the embodiments 1 and 2. The same possibility exists in the embodiment according to FIG. 3.
FIGS. 5 and 6 illustrate the use of certain locking fastenings between the casing parts, such as the base 2 and the cap 3. The cross-sectional shape of the ribs 15 and locking grooves 16 used is selected so that a through opening 8" is formed, if the cap wall is expanded when internal pressure peak values occur, so that the locking grooves 16 are raised from the ribs 15. The design and dimensioning of the locking connection are to be such that there is an effective pressure relief of the fuse element chamber, without completely eliminating the engagement of the ribs 15 in the locking grooves 16. The arrows in FIG. 6 indicate the flow path of a gas volume proportion on its way to the outside.
The miniature fuses in the embodiments according to FIGS. 1,2,3 and 4, whereof in each case only a sectional view is shown, can either have a preferably circular cross-section, so that overall the fuses are cylindrical, or can be box-shaped, as shown in FIG. 7. The first part of the description indicated the pressure relief actions in the case of fuses with a rectangular cross-section.
FIG. 8 shows a miniature fuse, whose cap 3 has an upper opening 17, which can be closed by means of a plastic cover 18 with a locking connection formed by ribs 15 and locking grooves 16. This makes it possible to obtain the relief action shown in FIGS. 5 and 6 when internal pressure peak values occur.
In the embodiment according to FIGS. 9 and 10 the same references indicate the same parts or parts of the same nature as in the preceding embodiments. However, it is important here that a locking fastening between the base 2 and the cap 3 is only provided on the small ends, so that if the internal pressure abruptly rises, a particularly marked opening gap 8" is obtained, as shown in the drawing. The latter illustrates the bulging or expansion of the cap 3 on reaching a high internal pressure value. In the normal or inoperative position the long sides of the base 2 and the cap 3 engage on one another. As is also shown in FIGS. 9 and 10, at least along part of the opening gap 8", cooling elements 19 can in particular be inserted in the base 2. The cooling elements 19 are made from materials with particulary good thermal conductivity and high specific thermal capacity. They are intended to reinforce the cooling obtained on the wall of the gap 8" when part of the gas flows out. | The invention relates to an electric fuse with a fuse element located in a housing which encases a fuse element chamber. The fuse element melts and thus cuts out the fuse under an overcharge, whereby the temperature and pressure in the interior of the casing will abruptly rise. The housing is provided with a pressure relief means through which at least part of the gas volume can be let off to the outside to prevent the housing from destruction if high internal pressure peak values occur on cutting out the fuse. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefits of U.S. Provisional Patent Application No. 60/836,329, filed Aug. 7, 2006, the disclosure of which is hereby incorporated by reference in its entirety including all figures, tables and drawings.
This invention was made with Government support under Grant No. 2001-344463-10521 awarded by the USDA. The Government has certain rights in the invention.
TECHNICAL FIELD
This invention describes a method for synthesizing carbohydrate acids through controlled oxidation of their corresponding carbohydrates using nitric acid and oxygen as the oxidizing agents.
BACKGROUND OF THE INVENTION
Carbohydrate acids, and in particular carbohydrate diacids (aldaric acids) offer significant economic potential as carbon based chemical building blocks for the chemical industry, as safe additives or components of products use in pharmaceutical preparations and food products, and as structural components of biodegradable polymers, if they can be effectively produced on an industrial scale. Glucaric acid, for example, is produced through the oxidation of glucose and in salt form is currently in use as a nutraceutical for preventing cancer. The price of this material however is high, approximately $100/lb. Industrial scale production of aldaric acids would also provide sufficient materials for the production of other useful compounds, that include environmentally degradable polyamides with varying properties and applications, which are otherwise not commercially available.
Carbohydrate diacids are produced a number of ways from reducing sugars using a variety of oxidizing agents, nitric acid being among the earliest reported. 1 An example of a nitric acid oxidation of a carbohydrate is that of D-glucose to give D-glucaric acid, typically isolated as its mono potassium salt. 2,3,4 Alternatively, D-glucaric acid can be isolated from nitric acid oxidation of D-glucose as a disodium salt 5 or as the 1,4:6,3-dilactone. 6 Routes have been described showing synthesis of diacids through catalytic oxidation with oxygen over a noble metal catalyst. 7 An additional route of synthesis exists by use of oxoammonium salts in combination with hypophalites as the terminal oxidants. For example, Merbough and coworkers describe oxidation of D-glucose, D-mannose and D-galactose to their corresponding diacids using 4-acetylamino-2,2,4,6-tetamethyl-1-piperidinyloxy (4-AcNH-TEMPO) with hypohalites as the oxidizing medium. 8,9 A microbial oxidation of myo-inositol to glucuronic acid which is then oxidized enzymatically or by catalytic oxidation to glucaric acid has also been recently described. 10
When used to oxidize carbohydrates to carbohydrate acids, nitric acid offers the advantages of conveniently serving as the solvent medium for the oxidation and as an oxidizing agent. However, there are also specific disadvantages. Such oxidation reactions can be very exothermic and may run away if care is not taken to control the exotherm in the early stages of the reaction. These reactions also generate significant amounts of NOX gases which are environmental hazards if they are vented into the atmosphere rather than being captured and rendered harmless and/or recycled in a process that regenerates nitric acid. Thus, it would be desirable to utilize a more controlled nitric acid oxidation process that does not run the burdensome, time consuming, and inefficient risk of over-reaction, thereby rendering the products essentially useless, while at the same time employing a process that does not vent NOX gases into the atmosphere, and recycles these gases into nitric acid.
In the nitric acid oxidation of many compounds, product isolation can be encumbered by the residual nitric acid that remains in the usually syrupy product. Thus, in order to properly isolate the desired oxidation product, it is generally necessary to remove the residual nitric acid. This is particularly the case in the nitric acid oxidation of alcohol compounds, such as carbohydrates. In order to isolate the desired oxidation product of a carbohydrate, nitric acid must be at least partially removed. A number of methods have been described for removing residual nitric acid.
The first technique involves neutralizing aqueous nitric acid and organic/carbohydrate acids solution at the end of the oxidation step with hydroxide solution. In the case of D-glucose oxidation to obtain D-glucaric acid, potassium hydroxide is the base of choice and back titration with nitric acid yields the monopotassium salt of D-glucaric acid. 3,4 This technique is not advantageous due to the cost and difficulty involved in the neutralization step.
A second technique for removing residual nitric acid from the oxidation product involves repeated concentrations, by a distillation process, using additions of fresh quantities of water between each step, 2,6 after the bulk of the nitric acid has been removed by a distillation process of some type. Removal of residual nitric acid in this manner is very energy intensive requiring multiple additional distillations and does not efficiently remove all of the nitric acid.
Yet a third technique for removing residual nitric acid involves adding large volumes of 2-propanol in order to destroy any excess nitric acid. 11 The 2-propanol addition is followed by water dilution and concentration of the remaining product. This process further requires the consumption of 2-propanol, resulting in acetone and other residuals that must also be isolated and separated from the oxidation product. Further, this technique also describes treatment with water and hydrogen chloride, both of which must be removed from the oxidation product. This third technique involves too many steps to be economically viable.
As mentioned earlier, another disadvantage to nitric acid carbohydrate oxidation processes previously reported is the big exotherm normally associated with these oxidations. In those previous processes, the entire amount of solid carbohydrate, along with the entire amount of inorganic nitrite, which serves as a reaction activating agent, is mixed with the nitric acid at the outset of the reaction, thereby creating the conditions for a large and difficult to control exotherm that develops as the reaction warms. Alternatively, the solid carbohydrate is added portion-wise to the nitric acid. This process still promotes an extensive exothermic reaction and is also encumbered by the difficulty in adding solid carbohydrate portion-wise to the liquid/gaseous reaction mixture. Furthermore, isolation of the carbohydrate acid as a salt can also be made difficult due to the presence of inorganic nitrate which can contaminate carbohydrate acid salts during their isolation process.
Thus, significant industrial scale production of aldaric acids requires an economically efficient and a less complicated method for synthesizing aldaric acids from their corresponding carbohydrates. At this time, for example, D-glucaric is not manufactured on a significant industrial scale because there is no economically viable means for such production. The potential importance of D-glucaric acid as a chemical staple from renewable resources was recently underscored in a report by T. Werpy and G. Petersen. 12 From among hundreds of compounds considered as potential key chemical building blocks from renewable resources, glucaric acid was targeted as one of the top twelve molecules with significant potential as a chemical building block for a range of potential applications. Also included with glucaric acid were the structurally related pentaric acids, xylaric acid 11 from biomass xylose and arabinaric acid from biomass arabinose. The need for suitable oxidation methods of the precursor monosaccharides was emphasized by Werpy and Peterson. If a suitable economic means for the oxidation of carbohydrates could be found, the production of D-glucaric acid and other aldaric acids could see increased production, lower prices, and greater public availability.
All patents, patent applications, provisional patent applications and publications referred to or cited herein, are incorporated by reference in their entirety to the extent they are not inconsistent with the teachings of the specification.
SUMMARY OF THE INVENTION
An improved method for oxidation of water soluble organic compounds subject to nitric acid oxidation, and particularly carbohydrates of different structures, stereochemistry, and origins, to their corresponding carbohydrate acids, including aldaric acids, addresses issues normally arising in common nitric acid oxidation methodologies. Specifically, the subject method serves to eliminate thermal control issues in the oxidation, the release of oxides of nitrogen into the atmosphere, but provides for removal of post-reaction nitric acid and inorganic compounds, while employing a catalytic process involving use of oxygen to carry out the desired oxidations. As a result, beneficial carbohydrate acids which were previously expensive and burdensome to produce can become relatively cheap and readily obtainable. Furthermore, many aldaric acids that were previously unavailable are now capable of industrial production and commercial development.
The first step of the subject method is the computer-controlled, catalytic oxidation reaction, wherein nitric acid is put in a closed reactor in contact with various carbohydrate feedstocks under very mild and controlled conditions of oxygen pressure, reaction time, and reaction temperature to allow the oxidation of the carbohydrates to occur. Oxygen consumption in the presence of the aqueous acid solution is associated with nitric acid regeneration from various NOX gases as they are produced in the reaction. Carrying out this step in a controlled manner under relatively low temperature over time avoids the big exotherm normally associated with nitric acid oxidations. The next step in the process is to isolate the oxidized product by removing and recovering the bulk of the nitric acid by distillation, then treating the resulting product with inorganic hydroxide to a basic pH in order to neutralize any residual nitric acid and convert carbohydrate acids into their corresponding acid salts. The resulting aqueous solution, which contains inorganic nitrate and the salt(s) of the product carbohydrate acid(s), is subjected to a filtration leaving the retentate containing the organic acid(s) salt form(s) and the permeate containing the inorganic salts. At this stage, the absence of most of the nitric acid and/or inorganic nitrate from the retentate renders the ease of purification and isolation of the carbohydrate acid non-salt(s) product(s) much improved over previously reported methods. An additional method employed to separate nitric acid from product organic/carbohydrate acids is diffusion dialysis technology. This low energy process is typically employed to separate inorganic acids from metal salts, 13,14 particularly multivalent cation salts, but has not been applied extensively, or at all, to separation of inorganic acids from carbohydrates or carbohydrate acids. The nitric acid recovery stream and organic/carbohydrate acids products streams can be separately processed for nitric acid reuse and organic/carbohydrate acids salts isolation, respectively. Diffusion dialysis separation of nitric acid from organic/carbohydrate acid products offers the additional option of being applied to the oxidation mixture before or after evaporative removal of some portion of the nitric acid, depending upon the advantage that can be utilized on an industrial scale. As with the filtration technology, application of the diffusion dialysis technology ultimately improves product isolation.
DETAILED DESCRIPTION OF THE INVENTION
The process of the subject invention is a convenient, simple and general catalytic oxidation process for converting available carbohydrates into their various corresponding acids.
The first step of the subject method is the controlled oxidation of various carbohydrate feed-stocks with nitric acid. The oxidation reaction is accomplished by charging a reactor with nitric acid, in the molar ratio range of 2:1 to 10:1, nitric acid to starting monosaccharide(s) and/or monosaccharide(s) units as found in di-, oligo- and/or polysacchararide(s). Continuous monitoring and control of reaction temperature, pressure, and stirring rate, plus introduction of gases and addition of liquids and/or solutions to the reaction is computer controlled. The reactor is then put under a positive pressure of oxygen and an aqueous solution of the carbohydrate is pumped into the nitric acid at a chosen programmed rate. The typical large exotherm associated with nitric acid oxidations of carbohydrates is avoided by carrying out the addition of the aqueous carbohydrate solution at a relatively low temperature, typically 20-30° C., while the reaction mixture is under positive pressure of oxygen. Nitric acid oxidation temperatures of 44-48° C. were previously reported for oxidation of D-glucose and D-xylose when the reaction mixture was cooled by bubbling oxygen or nitrogen gas through the reaction mixtures. 5 However, the latter oxidations were not carried out under an atmosphere of oxygen in a closed reactor, and the gases were employed to cool the reaction mixture. Employing the improved method, the reaction temperatures required are significantly lower than the typical temperatures of 55-65° C. reported for the oxidation of D-glucose. 2-5 Concurrently, multiple, small measured amounts of inorganic nitrite, such as sodium or potassium nitrite, in aqueous solution are added over time, to the reaction mixture within the closed reactor according to a programmed recipe. The addition of aqueous inorganic nitrite in such a manner provides for continued reaction activation during the entire addition period of the aqueous carbohydrate solution, as opposed to a short and less effective activation protocol wherein several small portions of solid inorganic nitrite were added over a brief (20 minutes) period of time as previously reported. 4
Once the above-mentioned additions are complete, the reaction temperature can be maintained or changed in a controlled manner, typically to a slightly higher temperature, while at the same time oxygen pressure can be programmatically maintained or changed to a desired level. Both reaction temperature and pressure can be controlled for as long as desired. Typically, the entire oxidation process is carried out in under 8 hours.
Also produced in the oxidation are gaseous oxides of nitrogen (NOX gases), dominated by nitrogen dioxide and nitric oxide which are recycled to nitric acid in an aqueous/oxygen environment. 15 Other NOX gases, such as nitrous oxide, require additional abatement processing. Existing technologies are employed in industrial nitric acid oxidations, notably nitric acid oxidation of cyclohexanol/cyclohexanone to adipic acid, that abate most of the oxides of nitrogen from those processes 16 and can be applied to the applicants' invention described here.
This reaction can be described as a catalytic oxygenation process wherein nitric acid serves as the direct source of the actual oxidizing species, but is regenerated in part through the use of oxygen that is consumed during the course of the reaction, and which serves as an oxidizing agent for conversion of low oxidation state NOX gases to higher nitrogen oxidation state NOX gases, e.g,. NO to NO 2 . 15 Added oxygen may play additional positive roles in the oxidation mechanism but those roles are not clearly determined at this time. However, the use of oxygen in the reaction as indicated allows the oxidation to proceed at relatively low temperature, typically 25-40° C. for hexoses, such as D-glucose and D-mannose, and somewhat higher temperatures for pentoses, such as D-xylose. The higher oxidation temperature required for pentoses may result from the difference in reactivity of the terminal primary hydroxyl groups compared to those of the hexoses. When a pentopyranose or hexopyranose ring form (predominant forms of pentoses and hexoses in aqueous solution) is oxidized, the dominant first site of oxidation is at the anomeric hydroxyl group, generating the corresponding six-membered, 1,5-aldono lactone. The terminal (C-6) hydroxyl group on hexose-derived aldono lactones is directly available for oxidation to a carboxylic acid function, whereas the terminal (C-5) hydroxyl group on pentose-derived aldono lactones is tied up in the lactone ring and is only available for oxidation upon hydrolysis of the lactone to the acyclic aldonic acid structure. Thus, oxidation of the terminal hydroxyl group of the pentose-derived aldonic acid is found to require a higher reaction temperature, presumably in order to facilitate the necessary hydrolysis of the lactone in the aqueous acid medium, to generate the ring open aldonic acid with a terminal hydroxyl group that is now available for the second oxidation to occur.
Employing the computer controlled process as described also significantly allows for improved opportunities for selective oxidations. As illustrated with the pentoses, the first oxidation step produces predominantly the monocarboxylic acid lactone (aldono lactone), which under the reaction conditions can be in equilibrium with the open chain aldonic acid. The same type of selectivity is observed with the hexoses and aldoses in general, an aldonic acid is formed first by oxidation at aldehyde/anomeric carbon, followed by further oxidation at a second site, primarily at the terminal hydroxyl group, but not limited to the terminal hydroxyl group. In general, the second oxidation on a carbohydrate substrate typically requires more severe reaction conditions than are required for the first oxidation, e.g., longer reaction time, increased temperature, additional nitric acid, etc., to accomplish the oxidation. The reaction rates for the first oxidation and for additional oxidation reactions vary depending upon which carbohydrate is being oxidized. Consequently, use of a computer controlled reaction process, allows for ready selection of reaction parameters that can be applied to specifically produce as a dominant product, a single oxidation product, a double oxidation product, etc., or a mixture of carbohydrate derived oxidation products that may have added value because they perform in an application as required but don't require added processing and expense needed for isolation of a single oxidation product, from carbohydrates of various classes (aldoses, ketoses, di- and larger saccharides, aldonic acids, alduronic acids, alditols, etc.).
The reaction parameter control and convenience that comes with the application of this technology makes it possible to carry out selective oxidations on a range of organic compounds subject to nitric acid oxidation, to make a range of oxidized products.
Organic compounds subject to nitric acid oxidation useful in the subject method include alcohols, aldehydes, ketones, and carbohydrates. Carbohydrates useful in the subject method include, but are not limited to, monosaccharides, such as the common monosaccharides D-glucose, D-mannose, D-xylose, L-arabinose, D-arabinose, D-galactose, D-arabinose, D-ribose, D-fructose; disaccharides, such as the common disaccharides maltose, sucrose, isomaltose, and lactose; oligosaccharides, for example, maltotriose and maltotetrose; aldonic acids such as D-gluconic acid, D-ribonic acid, and D-galactonic acid; aldonic acid esters, lactones and salts that include but are not limited to those derived from D-gluconic acid, D-ribonic acid and D-galactonic acid; alduronic acids, for example, D-glucuronic acid and L-iduronic acid; alduronic esters, lactones and salts that include but are not limited to those derived from D-glucuronic acid and L-iduronic acid; alditols that include glycerol, threitol, erythritol, xylitol, D-glucitol; alditols with more than six carbon atoms; cyclitols, for example common cyclitols such as myo-inositol and scyllitol; corn syrups with different dextrose equivalent values; mixtures of carbohydrates from different biomass, plant or microorganism sources; polysaccharides from biomass, plant or microorganism sources and of varying structures, saccharide units and molecular weights.
Suitable inorganic nitrites for use in the subject method include but are not limited to ammonium nitrite, sodium nitrite, potassium nitrite, lithium nitrite and any available nitrite salt.
In order to isolate the target aldaric acids, the bulk of the nitric acid is first removed from the reaction mixture. Two methods for separating the nitric acid from the organic product(s) are: 1) evaporation or distillation of the nitric acid, often under reduced pressure; 2) diffusion dialysis. The bulk of the product(s) composition from nitric acid oxidation of carbohydrates are organic acids comprised of primarily carbohydrate acids and to a small extent, non-carbohydrate acids such as glycolic acid and oxalic acid. All of these acid products will be simply designated hereafter as organic acids or organic acid(s) products. In reported oxidations, in order to isolate the target aldaric acids, the solvent/reagent nitric acid is either converted to inorganic nitrate with base (e.g., potassium hydroxide 3,4 ) and/or removed by an evaporation process. 2,6,11 Neutralization to a pH>7 with inorganic base, without removal of nitric acid, requires base for all of the nitric acid plus the organic/carbohydrate acid(s) and the nitric acid is not directly recovered for further use. In contrast, partial recovery of the nitric acid for reuse by vacuum distillation is advantageous because the recovered nitric acid can be used again for oxidation purposes, although it is difficult to remove all the residual nitric acid from the syrupy residue with ease. The second method for nitric acid recovery is through the use of diffusion dialysis. This process is typically used for the separation of common inorganic acids such as hydrochloric acid, sulfuric acid, or nitric acid from multivalent metal cations such as Cu ++ or Zn ++ . 13,14 The aqueous acid feedstock of the inorganic acid and metal salt(s) and a separate water stream are routed through a diffusion dialysis system consisting of low pressure pumps and an appropriate membrane system. Two aqueous exit streams are generated, an acid recovery stream comprised primarily of inorganic acid with some metal salt(s), and a product recovery stream comprised of primarily metal salt(s) with some inorganic acid. The separate streams can be subjected to further diffusion dialysis as needed to give a stream with higher inorganic acid concentration and lower metal salt(s) concentrations, and a stream with higher metal salt(s) concentration and lower inorganic acid concentration. This separation technique was applied to nitric acid oxidation reaction mixtures as prepared by the described methods herein, and was found to perform in the same manner as used in separation of inorganic acid(s) from metal salt(s). The bulk of the nitric acid with some organic acid(s) product(s), was in the acid recovery stream, and the bulk of the organic acid(s) product(s) with some of the nitric acid, was in the organic product recovery stream. The use of this technology to separate nitric acid from the organic acid(s) product(s) produced from the oxidation process described here is a very low energy process, operates at ambient temperature, and can be run continuously. It offers an additional advantage over direct evaporation/distillation of nitric acid from the reaction mixture in that in the latter process, additional oxidative processes can occur generating additional NOX gases that have to be contained, removed and/or converted to oxides of nitrogen that are convertible to nitric acid. In contrast, the recovered nitric acid from the diffusion dialysis process is low in carbohydrate product content and evaporation/distillation of the recovered nitric acid is achieved with minimal oxidation and NOX formation occurring during nitric acid recovery.
Depending upon the starting carbohydrate(s), the specific reaction conditions employed, and the target product(s) this solution can be treated accordingly to give the carbohydrate acid(s) in one or more forms. Aldaric acids can be obtained in free acid forms, as disalts, mono salts, acid lactones, and/or dilactones, or as mixtures of various salt forms, and/or acid and/or acid lactone forms. Aldonic acids can be isolated as their free acid forms, and/or lactones, and/or mixtures of salts. Acids generated from oligosaccharides and other higher molecular weight carbohydrates are mixtures which can contain some of the above aldonic and aldaric acids plus higher molecular weight acids derived from higher molecular weight carbohydrates. These acids can be also be obtained in various acid, lactone and salt forms.
The presence of residual nitric acid in the syrupy product makes it difficult to isolate an acid form or lactone form of the target carbohydrate acid(s). It was recently demonstrated that improved isolation of the dilactone form of both D-glucaric and D-mannaric acid 6 was possible, but only after more complete removal of residual nitric acid by extraction with an ether followed and drying under high vacuum. 6 When oxidation product(s) is (are) obtained from direct concentration of the reaction mixture that removes most of the nitric acid, or by subjecting the oxidation reaction mixture to diffusion dialysis followed by removal of the bulk of the remaining nitric acid by an evaporation/distillation step, residual nitric acid can be removed as nitrate and recovered by a membrane filtration method. When the resultant syrupy product/residual nitric acid mixture is treated with inorganic hydroxide to a pH>7, the resulting solution contains inorganic nitrate and the salt(s) of the product organic acid(s). This solution is then subjected to filtration, typically nanofiltration, with the bulk of inorganic nitrate passing through the membrane and into the permeate, and the bulk of the organic product remaining in the retentate. Removal of inorganic nitrate from carbohydrate acid salts after nitric acid oxidation was previously reported using ion retardation chromatography. 5 However, that method is not as fast, not as applicable on a large scale, and not as efficient as the filtration method described here. In the instant process, the remaining retentate contains the organic acid(s) salt form(s) with no to low inorganic salt content. The presence of only small amounts of inorganic nitrate in the organic acid(s) salts product(s) renders purification and/or isolation of the aldaric acid salt(s) product(s) or non-salt product(s) much improved over previously reported methods.
Overall, the use of a computer controlled reaction process, adding the carbohydrate and inorganic nitrite to the nitric acid in aqueous solution, and carrying out the oxidation in a closed reactor under a positive pressure of oxygen allows oxidations of carbohydrates with nitric acid to be carried out under very mild conditions in a catalytic fashion. Isolation and purification of the carbohydrate acid(s) and/or salt form(s) is considerably improved by removing the bulk of nitric acid by distillation under reduced pressure and/or separating the nitric acid from the carbohydrate acid(s) by diffusion dialysis and then recovering nitric acid using an evaporation/distillation process. Thereafter, neutralization of residual nitric acid and organic acid(s) product(s) with inorganic hydroxide can be followed by separation of residual inorganic nitrate from organic acid(s) salt(s) using filtration technology.
The following examples are offered to further illustrate but not limit both the compositions and the methods of the present invention. All percentages are by weight and all solvent mixture proportions are by volume unless otherwise noted.
EXAMPLE 1
General Methods
Solutions were concentrated in vacuo (10-15 mbar) using a rotary evaporator and water bath at 50° C. pH measurements were made with a Thermo Orion 310 pH meter (Thermo Fisher Scientific, Inc., Waltham, Mass., USA) which was calibrated prior to use. Oxidations were carried out in Mettler Toledo Labmax reactor. The Labmax reactor is designed to operate as a computer controlled closed-system reactor. The Labmax was fitted with a top-loading balance, a liquid feed pump, an oxygen Sierra flow valve, a mechanically driven stirring rod, a thermometer, a 1 liter thermal jacketed flask, a FTS recirculating chiller, a pressure manifold fitted with pressure relief valves and pressure gauge and a personal computer with CamileTG v 1.2 software. The software installed allows the operator to program experiments based on specific parameters and conditions.
EXAMPLE 2
Nitric Acid Oxidation of D-glucose
The aqueous 62.3% D-glucose solution used in the oxidations was prepared by adding solid D-glucose (162.5 g, 0.75 mol) to 97.5 grams of deionized water in a screw-capped flask containing a stir bar. Prior to adding solid D-glucose to the water, the water was heated to ca. 60° C. with stirring. Once the D-glucose was dissolved, the temperature was reduced to ambient and dry sodium nitrite (0.60 g) added to the solution. The total weight of the solution is 260.6 g.
The Recipe Menu is accessed using the Labmax CamileTG v1.2 software and the reaction parameters for the oxidation were programmed in a series of stages: Stage 1—the reactor temperature was set at 25° C.; the stirring rod speed set at 200 rpm (and held constant throughout all the remaining stages); time set for 1 minute. Stage 2—the reactor temperature was set at 25° C., and the pressure set at 0.25 bar for a duration of 3 minutes. Stage 3—the temperature of the reactor was set at 25° C., the pressure at 0.25 bar, and 43.3 grams of a 62.3% (w/w) D-glucose solution, containing 0.23% by weight of sodium nitrite, set to be added over 30 minutes. Stage 4—the reactor temperature was set at 25° C., the pressure maintained at 0.25 bar, and the duration of the stage set to 10 minutes. Stage 5—the reactor temperature was set at 25° C., the pressure at 0.25 bar, and 172.9 grams of the 62.3% (w/w) D-glucose solution, containing 0.23% by weight of sodium nitrite, set to be added over a 90 minute period. Stage 6—a 5 minute stabilization period was set where the temperature remains at 25° C. and the pressure at 0.25 bar. Stage 7—the temperature of the reactor was set to rise to 30° C. and the pressure set to increase to 0.50 bar over 60 minutes. Stage 8 was set for a duration of 180 minutes, the temperature and pressure set to remain constant at 30° C. and 0.50 bar, respectively. Stage 9—the reactor temperature was set to cool to 25° C. over 10 minutes. Once the reaction has been programmed to proceed as indicated, nitric acid (68-70%, 187 mL, ca. 3.0 mol) was added to the reactor. The reaction recipe was initiated and starting at stage 1, the reactor was closed to the atmosphere. In addition to activating the reaction recipe the hardware components of the reactor were also activated. Those hardware components include a top-loading balance, a liquid feed pump, pressure sensor, thermometer, oxygen Sierra flow valve, an FTS recirculating chiller and oxygen canister with a pressure regulator preset at 38.5 psi.
When the reaction had progressed through all of the stages, the reaction mixture was cooled to room temperature and then removed from the reactor through the bottom valve of the reactor.
The reaction mixture can then be worked up using different procedures. In one procedure the reaction mixture was concentrated at reduced pressure (rotary evaporator) with adequate cooling. The first fraction distilled at ca. 23-34° C. and 50-120 millibar of pressure and appeared to be NOX gases as evidenced from the brown color of nitrogen dioxide gas. The liquid distillate fractions distilled between 26-43 millibars and 26-39° C. and have specific gravities that increase from 1.05 to 1.25, in keeping with the negative azeotropic character of nitric acid. In a second procedure, separation of nitric acid from organic product was carried out employing diffusion dialysis. The Mech-Chem Diffusion Dialysis Acid Purification System laboratory scale Model AP-L05 was used to separate nitric acid from the organic product. The Mech-Chem system contains two metering pumps, the first being the acid reclaim pump and the second being the acid reject pump. Oxidation of D-glucose as described above was repeated five times, each reaction mixture was diluted with reverse osmosis (RO) filtered water to a volume of 1000 mL. The organic product concentration was estimated to be about 0.75 molar, and the nitric acid concentration estimated to be about 3.0 molar. The acid reject pump was set at 30% (pump length) and 30% (pump speed) and the acid reclaim pump was set at 40% (pump length) and 40% (pump speed). This put the reclaim to acid reject ratio at about 1.2. The system was first primed with RO water according to a standard setup procedure and then the water was removed from the acid tank in the unit. The acid tank was then filled with the diluted aqueous oxidation mixture and the water tank in the unit was filled with RO water. The acid purification unit was turned on with the pumps set as indicated and the process was initiated. Over a period of some 74 hours of processing, the entire oxidation mixture solution (approximately 5 liters) was added to the acid feed tank, RO water added to water feed tank, and the acid recovery stream and product recovery streams were collected. Samples were take periodically and analyzed using a Dionex ICS-2000 Ion Chromatography (IC) System. Concentrations of components of samples taken from the acid recovery stream and product recovery stream were reported in parts-per-million. Analysis of the IC data showed that >90% of the nitric acid was in the acid recovery stream along with 30% of the organic product. The product recovery stream contained <10% of the nitric acid and 70% of the organic product. The nitric acid from the nitric acid stream was recovered by a standard distillation process and the organic product from the product reclaim stream recovered by basification as described, then used directly or subjected to the nanofiltration procedure as needed to further remove inorganic nitrate.
Isolation of glucaric acid as its disodium salt. 5 D-Glucose (162.5 g, 0.75 mol) was oxidized using the LabMax reactor as described. Following the completion of the reaction, the reaction solution was concentrated to a white foam in vacuo (10-15 mbar) using a rotary evaporator and water bath at 50° C. The concentrate of organic product(s) and residual nitric acid was diluted with deionized water (150 mL), titrated with sodium hydroxide solution (5 M) to an approximate pH of 9.5, and then diluted with deionized water (3700 mL), giving an approximate 2.5% (w/w) solids solution. This solution was then filtered using a nanofiltration unit. The nanofiltration unit, built in-house, is comprised of the necessary valves, pump, lines, pressure gauge and an appropriate membrane such as a GE DL2540F membrane. When the permeate volume reached 1000 mL, 1000 mL of reverse osmosis (RO) purified water was added to the feedstock. The typical rate of the permeate flow when reducing the volume by 1000 mL was 48 mL/min. When 2000 mL of permeate was removed, another 1000 mL of RO water was added to the feedstock. The typical rate of permeate flow when removing the second 1000 mL was 45 mL/min. This procedure was repeated until a total of 4000 mL had been removed via the permeate and 4000 mL of RO water had been added to the feedstock. The typical permeate flow rate when removing the last 1000 mL was 43 mL/min. The filtration process was continued after the last 1000 mL of RO water was added to the feedstock until the permeate flow slowed to a trickle at which time the filtration was stopped. The final volumes of the retentate and permeate were 2800 mL and 5200 mL, respectively. Analysis of the permeate and retentate by ion chromatography (IC) indicated that sodium nitrate is the major component of the permeate and is present only in minor amounts in the retentate. The retentate was concentrated under reduced pressure using a rotary evaporator and further dried in a vacuum oven to yield crude disodium D-glucarate (186.52 g, 97.9% based on pure disodium D-glucarate). The salt was then dissolved in water, and the pH of the solution adjusted with sodium hydroxide to pH 8. The product was precipitated with methanol (1000 mL) as an off white solid (146.24 g, 76.7% based on pure disodium D-glucarate).
EXAMPLE 3
Nitric Acid Oxidation of D-glucose
The oxidation of D-glucose was carried out as in Examples 1 and 2. However, potassium hydroxide was substituted for sodium hydroxide in the neutralization process to give crude D-glucaric acid dipotassium salt (151.25 g, 70.4% based on pure dipotassium D-glucarate). The salt was precipitated from methanol as described to give an off white solid (145.75 g, 67.9% based on pure dipotassium D-glucarate).
Monopotassium D-glucarate isolation, Method 1. D-Glucose (162.5 g, 0.75 mol) was oxidized using the LabMax reactor and concentrated as described. The concentrate of organic product(s) and residual nitric acid was diluted with deionized water (150 mL) and chilled at 5° C. for 18 h. The pH of the solution was adjusted to a constant pH of 9.1 with 45% KOH (184 mL) in an ice bath and the solution back-titrated to pH 3.4 with concentrated HNO 3 (34.6 mL) in an ice bath. A precipitate formed when the solution pH dropped below 5. After cooling the mixture at 5° C. for 4 h, the precipitate was isolated by filtration. The off-white solid was returned to a beaker and triturated in water (200 mL) at 50° C. for 30 min then cooled to 5° C. for 1 h before isolating the solid by filtration. The solid was washed with cold water (20 mL) and dried in a vacuum oven to yield monopotassium D-glucarate 2-5 as a white solid (86.2 g, 0.347 mol, 46.3%).
Monopotassium D-glucarate isolation, Method 2. D-Glucose (162.5 g, 0.75 mol) was oxidized using the LabMax reactor and concentrated as described. The concentrate of organic product(s) and residual nitric acid was diluted with deionized water (500 mL) and chilled at 5° C. for 18 h. The pH of the solution was adjusted to a constant pH of 9.5 with 10% KOH (1.1 L) in an ice bath. The resulting brown solution was diluted to 4 L and processed using a nanofiltration procedure (e.g., a GE DL2540F membrane) as described. The pH of the retentate from the filtration was raised from 8 to 10 with 10% KOH (15 mL), the retentate concentrated using a rotary evaporator to a volume of 300 mL, and the solution pH adjusted to 3.4 with concentrated HCl (46.2 mL) in an ice bath. A precipitate formed when the solution pH dropped below 5. After cooling the mixture at 5° C. for 4 h, the precipitate was isolated by filtration. The off-white solid was returned to a beaker and triturated with cold water (200 mL) for 30 min. The solid was isolated by filtration, washed with cold water (20 mL), and dried in a vacuum oven to yield monopotassium D-glucarate as a white solid (87.4 g, 0.352 mol, 46.9%).
EXAMPLE 4
Nitric Acid Oxidation of D-gluconic Acid δ-lactone
The oxidation of D-gluconic acid δ-lactone was carried out as in Examples 1 and 2 with changes as noted in Stages 3 and 5 (Example 2). Stage 3—the temperature of the reactor was set at 25° C., the pressure at 0.25 bar, and 43.3 grams of a 62.3% (w/w) D-gluconic acid δ-lactone solution, containing 0.23% by weight of sodium nitrite, were set to be added over 30 minutes. Stage 5—the reactor temperature was set at 25° C., the pressure at 0.25 bar, and 170.5 grams of the 62.3% (w/w), D-gluconic acid δ-lactone containing 0.23% by weight of sodium nitrite, added over a 90 minute period. Product isolation can be carried out by any of the methods previously described.
EXAMPLE 5
Nitric Acid Oxidation of D-mannose
Oxidation of D-mannose was carried out using the Mettler Toledo RC-1 Labmax reactor as described in Examples 1 and 2 (D-glucose) with the following changes: The reactor was charged with the following 5.0 mol of nitric acid (312.5 mL, 68-70%). Stage 3—62.5% D-mannose solution (43.3 g) was added in place of D-glucose. Stage 5, 62.5% D-mannose solution (173.9 g) was added in place of D-glucose. In Stages 1-6 of the reaction the temperature was maintained at 30° C. and 0.25 bar. In Stage 7 the temperature was raised to 40° C., and maintained at that temperature through Stage 8, 6 h. Stage 9 remained unchanged.
Isolation of D-mannaric acid as its disodium salt. Prior to titration with sodium hydroxide the solution was stirred at 60° C. for approximately 45 min to promote equilibration between D-mannaric acid acid and lactone species. The isolation procedure was then followed as in Example 1 to give crude mannaric acid disodium salt: 144.4 grams (92% based on pure disodium D-mannarate).
EXAMPLE 6
Nitric Acid Oxidation of D-xylose
The procedure described in Examples 1 and 2 for D-glucose was applied to D-xylose using the same molar amount of starting D-xylose (112.52 g, 0.749 mol) and same amount of sodium nitrite (0.83 g). The differences in the stages for the oxidation process are as follows: addition stages 3 and 5 were combined [181.14 g of a 62.5% (w/w) D-xylose solution containing 0.46% by weight of sodium nitrite were added over 120 min], stage 4 was eliminated. The next change is in new stage 6 (glucose oxidation stage 7) wherein the temperature was raised to 35° C. and the pressure raised from 0.25 bar to 0.50 bar in 60 min. New stage 7 (glucose oxidation stage 8) reaction time increased from 180 to 210 min. New stage 8 is the same as glucose oxidation stage 9. After concentrating the reaction mixture, the resulting syrup was diluted with water (300 mL) and titrated with NaOH (5.0 M) to pH 3.5 to give an insoluble side product, disodium tetrahydroxybutanedioate acid 17 (8.39 g, 37.1 mmol, 4.95% yield) isolated by filtration. The filtrate was then further treated with sodium hydroxide to pH 8.5 and subjected to the filtration process as in Example 1. The aqueous retentate was concentrated to the solid crude disodium salt product (140.2 g, 624.7 mmol, 83.3% yield, based on pure disodium xylarate).
EXAMPLE 7
Nitric Acid Oxidation of L-Arabinose
The procedure described in Examples 1 and 2 for D-glucose was applied to L-arabinose using the same molar amount of starting L-arabinose (113.31 g, 0.754 mol) but an increased amount of nitric acid (320 mL, 5.31 mol). The differences in the stages for the oxidation process are as follows: addition stages 3 and 5 were combined [226.62 g of a 50% (w/w) L-arabinose solution containing 0.77% by weight of sodium nitrite are added over 90 min], stage 4 was eliminated. In new stage 6 (glucose oxidation stage 7) the temperature was raised to 50° C. and the pressure raised from 0.25 bar to 0.50 bar in 45 min. New stage 7 (glucose oxidation stage 8) reaction time increased from 180 to 240 min. New stage 8 is the same protocol as glucose oxidation stage 9. The oxidation mixture was then concentrated under reduced pressure as described in the glucose oxidation, yielding a thick syrup. The syrup was dissolved in 200 mL DI water and titrated with 5M NaOH to pH 3.5. A precipitate (disodium tetrahydroxybutanedioate, 17 4.26 g, 18.9 mmol, 2.5% yield) was removed by filtration. The resulting solution was then titrated with 5M NaOH, to pH 8.5, diluted to 3L with DI water and processed using the nanofiltration separation protocol. The resulting retentate was concentrated under reduced pressure and further dried overnight in a vacuum oven at 50° C. to yield crude disodium L-arabinarate (125.1 g, 558.2 mmol, 74.4% yield based on pure disodium L-arabinarate). The crude disodium L-arabinarate was triturated with ethanol (300 mL), separated by filtration, and dried under vacuum; yield 73.5%.
It is understood that the foregoing examples are merely illustrative of the present invention. Certain modifications of the articles and/or methods may be made and still achieve the objectives of the invention. Such modifications are contemplated as within the scope of the claimed invention.
REFERENCES
1. J. Stanek, M. Cerny, J. Kocourek and J. Pacak, “The Monosaccharides,” Academic Press, New York and London, 1963, p 741-752, and references therein.
2. W. N. Haworth and W. G. M. Jones, J. Chem. Soc., 65-76 (1944); b.
3. C. L. Mehltretter and C. E. Rist, Agric. and Food Chem., 1, 779-783 (1953)
4. C. L. Mehltretter, [14] “D-Glucaric Acid”, in Methods in Carbohydrate Chemistry, R. L. Whistler, M. L. Wolfrom, Eds; Academic Press, New York, 1962, Vol. II, pp 46-48.
5. D. E. Kiely, A. Carter and D. P. Shrout, U.S. Pat. No. 5,599,977, Feb. 4, 1997.
6. D. E. Kiely and G. Ponder, U.S. Pat. No. 6,049,004, Apr. 11, 2000.
7. C. L. Mehltretter, U.S. Pat. No. 2,472,168, Jun. 7, 1949.
8. N. Merbough, J. M. Bobbitt and C. Bruckner, J. Carbohydr. Chem., 21, 66-77 (2002).
9. N. Merbouh, J M. Bobbitt, and C. Bruckner, U.S. Pat. No. 6,498,269, Dec. 24, 2002.
10. W. A. Schroeder, P. M. Hicks, S. McFarlan, and T. W. Abraham, U.S. Patent Application, 20040185562, Sep. 24, 2004).
11. C. E. Cantrell, D. E. Kiely, G. J. Abruscato and J. M. Riordan, J. Org. Chem., 42, 3562-3567 (1977).
12. T. Werpy and G. Petersen (Eds.) Top Value Added Chemicals from Biomass, Vol 1—Results of Screening for Potential; http:/www.osti.gov/bridge or U.S. Department Of Energy, Office of Scientific and Technical Information, P.O. Box 62, Oak Ridge, Tenn. 37831-0062.
13. D. E. Bailey, U.S. Pat. No. 5,264,123, Nov. 23, 1993.
14. D. R. Olsen and D. E. Bailey, U.S. Pat. No. 5,562,828, Oct. 8, 1996.
15. “Advanced Inorganic Chemistry”, F. A. Cotton and G. Wilkinson, 5 th ed., John Wiley, pp 341-353, New York (1988).
16. Heike Mainhardt, “N 2 O Emissions from Adipic Acid and Nitric Acid Production,” in IPCC Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories, Jun. 15, 2001, and references therein.
17. A. Lachman, J. Amer. Chem. Soc., 43, 2091-2097 (1921). | A controlled nitric acid process employing oxygen and nitric acid as co-oxidants is used to oxidize organic compounds subject to nitric acid oxidation, to their corresponding carboxylic acids. Oxidation of some carbohydrates by this process can produce one or more of their corresponding acid forms. The process is carried out at moderate temperatures, typically in the range of 20° C. to 45° C. in a closed reactor, with oxygen gas being introduced into the reaction chamber as needed in order to sustain the reaction. Computer controlled reactors allow for careful and reproducible control of reaction parameters. Nitric acid can be recovered by a distillation/evaporation process, or by diffusion dialysis, the aqueous solution made basic with inorganic hydroxide, and the residual inorganic nitrate removed using a filtration (nanofiltration) device. The method eliminates issues of thermal control of the oxidation, release of nitrogen into the atmosphere, and post-reaction difficulties in the removal of nitric acid and inorganic nitrates. | 2 |
TECHNICAL FIELD
The invention relates to an SAW component (Surface Acoustic Wave component) which is assembled on a piezoelectric substrate, on which component structures are formed which comprise at least one inter-digital transducer for generating an SAW with the propagation velocity V SAW , wherein the slower shear wave with a propagation velocity V SSW can also occur in the piezoelectric substrate.
BACKGROUND
SAW components are assembled on piezoelectric substrates, mono-crystalline wafers being preferred, due to their favorable piezoelectric characteristics. The piezoelectric characteristics as well as a number of other characteristics, such as the propagation velocity of acoustic waves in the wafer, is dependent upon the orientation of the wafer surface relative to the crystal axes of the piezoelectric mono-crystal. Through suitable choice of the crystal cut, wafers can be made available in this manner whose cut-dependent characteristics support the desired performance of the SAW component.
Wafers with cut angles that support the effective generation and low-loss propagation of surface-proximate acoustic waves are normally used for SAW components. These include, for example, quartz wafers with an ST cut, lithium niobate wafers with a rot YX cut of ca. 40-65°, and lithium tantalite with a cut angle of intersection rot YX of 36 to 46°. In the case of most components on substrates having the cut angles indicated, a wave propagating into the bulk of the substrate is normally generated in addition to the SAW. Because the acoustic energy of such a wave cannot be used in the component, this results in transfer losses. For this reason, measures are necessary to minimize these losses. So far, however, the complete suppression of leakage wave losses has not been possible.
Another problem with substrates suitable for SAW components lies in the relatively high temperature coefficient of frequency. This refers to the temperature dependency of substrate characteristics, such as the propagation velocity of the surface wave. Ultimately, this also causes a temperature dependency of the center frequency of the component. Leakage wave substrates, when compared with quartz, exhibit a relatively high temperature coefficient of frequency TCF of ca. 40 ppm/K. To absorb this temperature coefficient of frequency, the bandwidth of SAW components produced thereon must be increased sufficiently so that the component and, in particular, an SAW filter can still fulfill the required specification.
The duplexer required for the US-PCS mobile wireless system is a filter application whose specifications place high demands on a component. Its specifications cannot be maintained with SAW components and/or substrate materials with the aforementioned high temperature coefficient of frequency. To this end, it would be necessary to reduce the temperature coefficient of frequency.
Various methods have already been proposed for reducing the temperature coefficient of frequency, each of which, however, is associated with another serious disadvantage.
Reversing the piezoelectric axis of the piezoelectric substrate on the surface of the wafer, thereby reducing the temperature coefficient of frequency, is known, for example, from an article by K. Nakamura and A. Tourlog, ‘Effect of a ferroelectric inversion layer on the temperature characteristics of SH-type surface acoustic waves on 36°Y-X LiTaO3 substrates,’ IEEE Trans. Ferroel. Freq. Ctrl. Vol. 41, No. 6, November 1994, pp. 872-875. The problem in this case, however, is the associated reduction in coupling, the difficulty in manufacturing and the limited reduction in the TCF to ca. 15 ppm/K.
Generating a thin lithium tantalate film on a wafer with lower temperature propagation is known from an article by K. Eda et al., ‘Direct Bonding of piezoelectric materials and its applications,’ IEEE Ultrason. Symp. Proc. 200, pp. 299-309. Because of the thermal distortion with the wafer, a component assembled thereon has a reduced temperature coefficient of frequency. A disadvantage worth noting in this context is that producing these substrate materials requires a complex technology, which generates high process complexity and, therefore, high costs.
Reducing the temperature coefficient of frequency of SAW components with an SiO 2 film applied onto the entire surface of the substrate and the metallization is known from an article by K. Asai, M. Hikita et al., ‘Experimental and theoretical investigation for temperature characteristics and propagation losses of SAWs on SiO 2 /Al/LiTaO 3 ,’ IEEE Ultrason. Symp. 2002 (to be published). In this context, however, it has come to light that the level of metallization must be substantially reduced in comparison to conventional SAW components. This results in increased attenuation, because the finger resistance in the transducers increases with reduced layer thickness. In addition, this method for reducing the temperature coefficient of frequency requires a very high layer thickness of the SiO 2 film of approx. 20% h/λ (that is, relative to the wavelength of the SAW that can be propagated therein). For this reason, the quality of the SiO 2 layer is crucial to the extent of the reduction achieved in the temperature coefficient of frequency and the insertion loss to be accepted.
However, implementing a US-PCS duplexer as an SAW component is not easily achieved with any of the methods proposed here.
SUMMARY
For this reason, the object of the present invention is to specify an SAW component, which is assembled on a leakage wave substrate and has a low temperature coefficient of frequency with low losses.
This object is achieved, according to the invention, by an SAW component with the characteristics of claim 1 . Advantageous embodiments of the invention follow from the additional claims.
The inventors have discovered a way of successfully suppressing the leakage wave losses and reducing the temperature coefficient of frequency by means of an additional synergistic measure. It was found that the development of leakage wave losses can be suppressed if the velocity of the surface wave and/or the SAW can be reduced to such an extent making it lie below the propagation velocity of the slow shear wave. This is achieved by sufficiently increasing the mass load by means of the metallization. This measure alone would increase the temperature coefficient of frequency. According to the invention, however, an additional compensation layer consisting of a material with low temperature dependency of the elastic coefficient is provided on the entire surface of the wave and the metallization applied to it. It was found that the SAW can be held in proximity to the substrate surface by means of a higher mass load. In the invention, this causes the SAW to propagate to a sufficient extent within the compensation layer and, as a result of the material properties of the compensation layer, experiences only a slight temperature dependency in its propagation behavior.
It is especially advantageous, in this regard, that only relatively small layer thicknesses are necessary to achieve both a mass load that is sufficiently increased in comparison with standard metallizations as well as for the compensation layer. The small layer thicknesses have the advantage that they are more easily controlled technologically, that they can be manufactured cost-effectively and that, in the combination of the two layers (metallizations with high mass load and compensation layer), they exhibit no negative effects on the component characteristics. As a result, an SAW component is obtained that, despite low insertion loss, has a sufficiently low temperature coefficient of frequency of, for example, less than 15 ppm/K. Such an SAW component structured as a filter is then, for example, also suitable for [use] as a duplexer for the US-PCS mobile wireless system.
To increase the mass load, a metallization with a higher specific weight than the aluminum normally used is used for the component structures and, in particular, for the transducer electrode (e.g., interdigital transducer). Preferably, a metallization is used whose mean density (averaged across all layers in a sandwich-type metallization structure) is at least 50% greater than that of aluminum.
Copper, molybdenum and tungsten have proven to be preferred electrode materials in this regard. For this reason, advantageous metallizations of the invention consist, in particular, of one of these metals, of an alloy consisting primarily of one or more of these metals, or of material layer combinations that contain layers of primarily one or several of the cited metals. On the basis of a metallization consisting almost exclusively of copper, the cited purpose is already achieved with a layer thickness corresponding to only about 10% h/λ (relative to the acoustic wavelength of the wave capable of propagation in the structure). This wavelength is not just dependent on one material, but rather on all materials of the structure and its dimensioning, that is, for example, on piezoelectric material, metallization and the compensation layer applied over the metallization. When compared with the 10% h/λ aluminum normally used, a metallization consisting of 10% h/λ Cu has the additional advantage that ohmic losses in the component can be reduced as a result of the high electric conductivity. In addition, Cu offers a high degree of resistance to acustomigration, so that it exhibits high power compatibility. Using a suitable process, Cu can also be produced as a quasi-unicrystalline layer, providing even more improvement with regard to conductivity and power compatibility.
If the mass load achieved in this regard is converted to the heavier metals Mo and W, the cited purpose is achieved with these metals with even smaller layer thicknesses.
Surprisingly, it has been shown that SiO 2 constitutes an especially suitable material for the compensation layer and, as a result of the correspondingly reversed temperature dependency of its elastic coefficients, a TCF with virtually 0 ppm/K can already be achieved with ca. 6% h/λ SiO 2 . The advantage of a compensation layer consisting of SiO 2 is that it is easily applied and compatible with both the component and its production steps. It has been shown that an SiO 2 compensation layer with a layer thickness of only ca. 4 to 8% h/λ is sufficient for suitable temperature coefficient of frequency compensation. This layer thickness is significantly smaller than the layer thickness of 20% h/λ proposed in the cited article by Asai et al., with which only the temperature coefficient of frequency is to be compensated. As a result, the thickness of the compensation layer is also smaller than the thickness of the metallization. The smaller layer thickness in the component of the invention is only possible because the SAW, as a result of the high mass load, can be pulled closer to the surface of the substrate, so that a thinner compensation layer already provides for sufficient reduction in the temperature coefficient of frequency.
A component of the invention is preferably assembled on a lithium tantalate substrate with a rotated profile, the preferred cut angles lying between 30 and 46° rot YX. Components on substrates with profiles selected in this manner exhibit especially favorable properties. In addition, the invention is especially advantageous with components assembled on such substrates.
A metallization preferably consisting primarily of copper was not previously used with SAW components due, on the one hand, to the associated high temperature coefficient of frequency occurring with high relative layer thicknesses and, on the other, to high corrosion sensitivity. Using the compensation layer of the invention, the latter problem of corrosion sensitivity is also successfully solved and the copper surfaces are protected against premature corrosion.
The adhesive strength of a metallization consisting primarily of copper can be improved with an adhesive layer additionally provided between the substrate and the metallization. Thin metal layers consisting, for example, of aluminum, molybdenum, nickel, titanium, tungsten or chromium are suitable for this purpose. Also suitable are multilayer adhesive layers or alloys of one or more of these metals, a total layer thickness of the adhesive layer of ca. 1 to 7 nm being sufficient. Adhesive layers with a thickness of 5 nm are generally sufficient.
The use of a copper as a metallization can be accompanied by increased production dispersion, which can be reduced, according to the invention, by a trimming process, which also results in an adjustment of the resonance frequency. To this end, the thickness of the compensation layer can varied across either the entire surface or parts of the surface during application, or it can be suitably etched following application. A dry etching process is preferably used when an SiO 2 layer is used as the compensation layer.
The quality of the SiO 2 layer also affects the properties of SAW components of the invention. This quality is primarily determined by the methods of application and the stoichiometry achieved as a result, especially with regard to the oxygen content of the SiO 2 layer. Layers of the composition SiO x , where 1.9≦x≦2.1, are especially suitable. SiO 2 layers characterized by a refractive index of between 1.43 and 1.49 are also highly suitable. Said layers can be produced to cover edges and be free of cavities by means, for example, of sputtering, a CVD process or a PVD process. This is also advantageous with respect to the aspects of process control and calculation of the parameters. It is advantageous to deposit the compensation layer and especially the SiO 2 layer at low temperatures. As a result, a compensation layer can be produced in which only minor intrinsic tensions prevail at room temperature.
A component of the invention having a copper metallization with a thickness of 10% h/λ, for example, an SiO 2 layer modified in the manner described above applied to it, and a layer thickness of 6% h/λ, for example, achieves a temperature coefficient of frequency of less than 15 ppm/K.
To further increase the corrosion resistance of the metallization, an additional, thin passivation layer, a thin aluminum oxide layer, for example, can be provided on top of the metallization. This can be applied directly by means of sputtering, for example, or, alternatively, by applying a thin aluminum layer and then converting it to the corresponding aluminum oxide by means of oxidation.
A thin gold layer on top of the copper also fulfills the corrosion resistance requirements, as well as serving as a starting point for an electrical connection to the exterior. In this connection, it is known that Au, especially as a basic material, is very well-suited for subsequent bumping.
An advantage of the invention, especially when the component (the chip) is installed in a housing or mounted on a module using the flip-chip method, is that the measures for reducing the TCF do not result in any differences in the structure, so that the standard methods can be used. No new resist or lithography processes are necessary, nor are deposition processes, wafer production processes or package technologies. The invention is independent of the component design and/or technology used for that purpose.
A component of the invention can, in particular, be structured as a DMS filter, which is already inherently characterized by low insertion loss. The invention can also be advantageously applied in the production of SPUDT filters (Single Phase Uni-Directional Transducer) as well as reactance and MPR filters (Multi-Port Resonator). Accordingly, the invention is also suitable for diplexers and duplexers, whose sub-filters correspond to one of said filter types. The invention is also well-suited for so-called 2-in-1 filters. A duplexer assembled using filters of the invention can, for the first time, satisfy the high standards for the US-PCS mobile wireless system, which was previously not yet possible with SAW filters.
In the following, the invention is explained in greater detail on the basis of exemplary embodiments and the corresponding figures. The figures are provided to improve comprehensibility and, therefore, are only schematic and are not true to scale.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an interdigital transducer, as an example of a metallization structure, in a top view
FIG. 2 shows the invention on the basis of a schematic cross-section through a metallization
FIG. 3 shows a metallization with an additional adhesive layer
FIG. 4 shows a metallization with an additional passivation layer
FIG. 5 shows a multilayer metallization
FIG. 6 shows the course of the temperature coefficient of frequency of metallizations consisting of Al and Cu, as a factor of the relative layer thickness of the metallization
FIG. 7 shows the course of the temperature coefficient of frequency of a 10% Cu metallization, as a factor of the relative layer thickness of an SiO 2 layer as compensation layer
DETAILED DESCRIPTION
FIG. 1 shows, in a top view, an interdigital transducer IDT known in the art as an example of a metallization of a transducer electrode of an SAW component of the invention. This transducer is a key element of the SAW component and provides for the electro-acoustic conversion of a high-frequency electric signal, applied, for example, to terminals T 1 , T 2 , into a surface wave, or for the corresponding retro-conversion of the surface wave into an electric signal. The interdigital transducer IDT comprises at least two electrodes having virtually parallel electrode fingers EF, the fingers of the electrodes being interdigitally pushed into one another. Both electrodes can each be provided with an electric terminal T 1 , T 2 , at which an electric signal can be input or output, or which can be connected to ground.
FIG. 2 shows a component of the invention on the basis of a schematic cross-section along the intersecting line 2 shown in FIG. 1 .
A metallization M, such as said interdigital transducer IDT, is applied onto the piezoelectric substrate, such as a lithium tantalate wafer with rot YX 39° cut. Here the metallization consists of pure copper or an alloy with a high copper content. The height h M of the metallization is adjusted, as a factor of the center frequency of the SAW component, to a value corresponding to ca. 10% of the wavelength of the acoustic wave capable of being propagated in the structure.
The metallization is, for example, deposited onto the entire surface by vacuum metallizing, sputtering, CVD or other processes, and then structured by means of lift-off technology. However, it is also possible to initially apply the metallization M onto the entire surface, then structuring it using an etching mask.
Once the metallization M. has been applied to the substrate S, in a structure as shown in FIG. 1 , for example, a compensation layer K, preferably covering edges and in uniform layer thickness, is then applied to the entire surface. The layer thickness h k is adjusted, for example, to a value of 6% relative to the wavelength of the acoustic wave capable of propagation in this structure. As already mentioned, trimming can be done secondarily by means of back-etching.
In addition to the interdigital transducer shown in FIG. 1 , the SAW component of the invention can comprise other metallization structures, which preferably all consist of the same material. The compensation layer K also preferably covers the entire surface of the substrate, with the exception of the electric terminal surfaces T 1 , T 2 provided for contacting. The metallization can be additionally thickened on the electric terminal surfaces, on the connecting lines and on the current rails connecting the electrode fingers EF. This thickening can be achieved, for example, with a galvanic process, the metallization structures that are not to be thickened preferably being covered. Said compensation layer, which is structured accordingly prior to the galvanic step, can be used as covering. The electrical connection of the component to external contacts can then be achieved through bump connections or another solder connection, such as wire bonding.
FIG. 3 shows another embodiment of the invention, in which a thin adhesive layer H having a thickness of 5 nm, for example, can be applied beneath the metallization M. Like the metallization M, the adhesive layer H can be applied to the entire surface and structured together with the metallization. An electrically conductive adhesive layer H can also be part of the metallization M. An electrically conductive adhesive layer H can also be part of the metallization M.
FIG. 4 shows another embodiment of the invention, in which, following production of the metallization M, a thin passivation layer is initially applied to the entire surface of the metallization M and the interspaced exposed surface of the substrate S. Such a passivation layer P can also consist of any electrically conductive material, especially a dense oxide, nitride or carbide. A DLC layer (Diamond-Like Carbon) is also well-suited for this purpose. With such a passivation layer P, especially effective protection of the metallization M against corrosion, such as uncontrolled oxidation by atmospheric oxygen, is prevented. With such a passivation layer P, the compensation layer K can be formed to be less dense, because passivation of the electrode by the compensation layer is not necessary.
A thickness of a few nanometers, 5 to 10 nm, for example, is sufficient as the layer thickness of the passivation layer P.
FIG. 5 shows another embodiment of the invention, in which a metallization M is used which is structured to be multi-layered. The figure, for example, shows a four-layer metallization structure with sub-layers M 1 , M 2 , M 3 and M 4 . To increase the mass load of the metallization in accordance with the invention, at least one of these layers is made of a material with high specific density, wherein at least one of the remaining layers can consist of a conventional electrode material, that is, of aluminum or an alloy containing aluminum. Preferably, an alternating layer sequence comprising at least two layers is selected, at least one of said layers consisting of the metals Mo, Cu or W. The layer thicknesses of the metallization layers can be selected to be identical or different, wherein electric conductivity and, as a result, resistance, as well as mass load, can be adjusted by means of the suitable combination of various layer thicknesses. In this context, it is only necessary to ensure that at a correspondingly lower mass load, a correspondingly higher layer thickness h M of the metallization must be maintained. Here, as in all exemplary embodiments, an SiO 2 layer with a layer thickness of ca. 4 to 10% h/λ serves as compensation layer K over the metallization M.
FIG. 6 shows, on the basis of a simulation calculation, the effects of various metallizations (without compensation layer) on the temperature coefficient of frequency (TCF) of the resonant frequency. The diagram shows the simulated course of the TCF as a factor of the mass load, which is plotted along the x axis as the metallization height relative to aluminum h M/Al . The different curves for the different metals Al and Cu were calculated here without a compensation layer. The metallization height is relative to aluminum and, in the case of high mass loads resulting from heavier metals, is reduced almost in proportion to the specific weight. The vertical division in the figure also indicates the limit for the mass load at which V SAW <V SSW . It becomes clear that this cannot be achieved with the known metallization made of aluminum.
FIG. 7 shows, on the basis of a simulation calculation, the reduction in the temperature coefficient of frequency that can be achieved by applying an SiO 2 layer to a structured Cu structure of 10% h/λ. The first value (at the zero point on the x axis) is calculated for a structure that corresponds to the last value, with the highest mass load (for a Cu metallization), indicated in FIG. 6 . It is evident that the relatively high TCF associated with the high mass load can be reduced to zero by means of the compensation layer, which is achieved, for the Cu structure of 10% h/λ on which the calculation is based, using an SiO 2 layer of 6% h/λ. A TCF of 0 is not achieved with a conventional Al metallization, even at minimal mass loads.
Even though the invention could only be described on the basis of a few exemplary embodiments, it is not limited to these. Combining the characteristics shown in the individual figures with one another also lies within the scope of the invention. Other variation options result from the selection of material, the layer thicknesses, the metallization structures and the types of components in which the invention can be used. | An apparatus including a piezoelectric substrate having at least one transducer electrode structure. The structure having a metallization formed by one or more metals with a mean specific density that is at least 50% higher than that of aluminum. The structure having a compensation layer that is applied fully or partially over the metallization. The compensation layer is of a material having a temperature dependence of elastic constants that counteracts the temperature coefficient of frequency of the substrate. The compensation layer has a thickness that is less than 15% of an acoustic wavelength of a wave capable of propagation in the structure. | 7 |
INCORPORATION BY REFERENCE
[0001] This application claims domestic priority under 35 USC §119(e) based upon provisional patent application No. 60/836,214 filed on Aug. 8, 2006. The entire provisional application No. 60/836,214 is hereby incorporated by reference as if set forth verbatim into this patent specification.
SUMMARY OF THE INVENTION
[0002] The invention is a high-strength yet lightweight material composed of interconnected struts that typically form a tetrahedral lattice structure. Each strut of the interconnected struts has first and second ends spaced from one another along a longitudinal axis. The strut has a generally triangular cross-section at planes perpendicular to this longitudinal axis. In a preferred embodiment, the triangular cross section comprises an isosceles triangle, with a pair of base-angles approximating 55 degrees. It is important that the first and second ends of each strut are equivalent to one another to facilitate the assembly of the struts into a lattice structure of these interconnected struts.
[0003] Each strut has a vertex point positioned at an outermost point with respect to the longitudinal axis. The vertex point is positioned on a line within a plane that symmetrically divides the triangular cross-section, and is the intersection point of a plurality of planar polygonal faces.
[0004] The first and second polygonal faces share a common edge and angle outwardly toward the vertex from the upper edge of the triangular cross-section. These first and second faces, preferably triangles, are generally symmetric about the common edge. Third and fourth faces of the end portions of the strut angle outwardly and upwardly from a base of the triangular cross section toward the vertex point. Preferably, the third and fourth faces share a common edge extending from the vertex point to the base of the triangular cross-section of the strut.
[0005] A manifold comprising fluid ducts may pass through each strut. In a preferred embodiment, a duct passes from the first face of one end of the strut to the second face of the other end. Another duct may do just the opposite and criss-cross it.
[0006] Comparatively, another pair of ducts may cross from the third and fourth faces of the opposing ends as well. Of course, other arrangements of the manifold are possible, including making the entire strut hollow so that a manifold can be created by interconnecting the struts into a lattice structure. Fluid may be injected, forced or moved through the manifold in order to regulate the temperature of the material.
[0007] The lattice structure, of course, will create a material that comprises struts and voids therebetween. The material may be made solid by pouring a filler (such as fiberglass, epoxy, concrete, or the like) into the lattice to fill these voids thereby creating a solid material.
[0008] Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of a first embodiment of the lattice structure, according to the principles of the invention.
[0010] FIG. 2 shows a perspective view of an alternate embodiment of the lattice structure.
[0011] FIG. 3 shows a perspective view of another alternate embodiment of the lattice structure.
[0012] FIG. 4 shows a perspective view detailing a unique method that incorporates the inventive lattice structure.
[0013] FIG. 5 shows a side view isolating a strut that comprises the lattice structure.
[0014] FIG. 6 is an end view isolating a strut that comprises the lattice structure.
[0015] FIG. 7 is a plan view isolating the strut that comprises the lattice structure
[0016] FIG. 8 is a bottom view isolating the strut that comprises the lattice structure.
[0017] FIG. 9 is a plan view of isolating a second preferred embodiment of a strut that comprises the lattice structure.
[0018] FIG. 10 is a bottom view isolating a second preferred embodiment of a strut that comprises the lattice structure.
[0019] FIG. 11 is a bottom view isolating the strut that comprises the lattice structure.
[0020] FIG. 12 is a plan view of isolating a second preferred embodiment of a strut that comprises the lattice structure.
[0021] FIG. 13 is a bottom view isolating a second preferred embodiment of a strut that comprises the lattice structure.
[0022] FIG. 14 and are perspective views detailing how the struts interconnect to form a tetrahedral lattice structure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] FIG. 1 gives a perspective view of a first embodiment of the lattice structure, according to the principles of the invention. As shown, the lattice structure 10 comprises a plurality of interconnected struts 12 that form triangles within a plane, and extend to form a tetrahedral spatial structure. In selected planes, the struts 12 form triangular structures with space therebetween. It is well-known that triangular support structures provide very stable, durable support, and are likewise resistant to trauma. The instant design takes full advantage of this principle regarding triangles, and simultaneously generate a relatively lightweight lattice structure because much of the structure is open space.
[0024] FIG. 2 shows a perspective view of an alternate embodiment of the lattice structure 10 . The view shown in FIG. 2 shows a lattice structure 10 that forms the general shape of a tetrahedron. This embodiment of the lattice structure 10 , as in previously discussed embodiment, will comprise interconnected struts 12 that form tetrahedral shapes within the lattice structure 10 . Additionally, the tetrahedrally-connected struts 12 may interconnect to form any type of shape, including a planar structure (as in FIG. 1 ), or even a larger lattice that itself forms a tetrahedron, as depicted here in FIG. 2 .
[0025] FIG. 3 shows a perspective view of yet another alternate embodiment of the lattice structure 10 . In this embodiment, tetrahedrally-connected struts 12 are interconnected and formed to create a cylindrical lattice structure 10 . This lattice structure may also comprise a hollow cylinder (as shown in FIG. 3 ), or it may comprise a generally-solid cylindrical structure.
[0026] FIG. 4 shows a perspective view that details how the lattice structure 12 may be used as an internal structure to enhance the durability of a solid material. In this embodiment, the lattice structure 10 is positioned within a mold 41 , and material in molten or liquid form is poured into the mold. The material 43 can be any known material, such as fiberglass, polyurethane, plastic, or even concrete. It is found that the lattice structure 12 within any cured material will enhance the durability and make the material more resistant to trauma and wear.
[0027] FIG. 4 a shows an alternate perspective view of how the lattice structure 12 may be used as an internal structure to enhance the durability of a solid material. In this embodiment, material 43 is inserted into the lattice structure with an inserter 51 that is directed appropriately. Comparatively, FIG. 4 b shows another embodiment of how material 43 may be inserted into the structure 12 . In the alternate method depicted in FIG. 4 b , the inserter 51 comprises numerous hoses or ducts that can penetrate into the lattice structure to better direct and manage insertion and filling of the lattice structure with material 43 in a more uniform manner.
[0028] FIG. 5 isolates the strut 12 and provides a side view thereof. The strut 12 extends along a longitudinal axis L to a vertex point 14 at an outermost point of each end of the strut 12 . The first side 26 of the strut 12 is shown to bear a generally planar configuration, but other shapes and configurations are also within the scope of this invention. However, experimentation has shown that planar configurations are preferred for the ease of manufacture.
[0029] As shown in FIG. 5 , the start 12 has a pair of opposed ends that are generally equivalent one another. For example, the first end face 16 bears an equivalent shape with the fourth end face 22 on the opposite end of the strut 12 . Likewise, the fourth end face 30 is generally equivalent to the eighth end face 36 .
[0030] FIG. 6 isolates the end view of the strut so that the configuration of the end faces 16 , 18 , 30 , 32 becomes more clear. The strut 12 bears a generally uniform isosceles triangular shape having a base 24 and legs 26 and 28 . As shown, upper end faces 30 and 32 are adjacent the spine edge 27 that forms vertex of the isosceles triangle. Preferably, the angle at the spine edge is slightly greater than sixty degrees—approximately 70 degrees. The four end feces 16 , 18 , 30 and 32 share vertex point 14 . Typically, the vertex point 14 is on a line that forms the altitude of the isosceles triangular cross-section. In that regard, the plane containing the altitude also provides a line of symmetry; note that the upper end faces 30 , 32 are symmetric about the altitude just as lower end faces 16 , 18 are symmetric about the altitude as well. The lower end faces 16 , 18 form right-angle trapezoids sharing a common edge through the altitude of the isosceles triangular cross-section.
[0031] FIG. 7 shows an overhead, plan view that isolates the strut 12 . The strut 12 has first side 26 and a second side 28 that meet at spine edge 27 . The spine edge 27 terminates where it adjoins the upper end feces 30 , 32 at one end, and upper faces 34 and 36 at the other. From the view shown in FIG. 7 , the line defining spine edge 27 provides a line of symmetry for end faces 30 and 32 . This same line through the spine edge 27 also provides a line of symmetry for end faces 34 and 36 . Also, note that opposite upper end faces 32 and 34 are equivalent to one another, as are opposite end faces 30 and 36 .
[0032] FIG. 8 isolates the bottom view of the strut 12 . The strut 12 has a base 24 that extends in a generally planar fashion along the longitudinal axis L of the strut, and termintes at each end with lower end laces 16 , 18 at one end, and lower end faces 20 , 22 at the other. As shown in FIG. 8 , the base forms a hexagonal shape bearing first line of symmetry about a plane through the longitudinal axis L, and a second line of symmetry about a line orthogonal to the longitudinal axis L.
[0033] FIG. 9 shows an overhead and plan view of alternate embodiment of the strut 12 . Structurally and spatially, the view of strut 12 of FIG. 9 is equivalent to the overhead plan view shown in FIG. 7 . For example, the strut in FIG. 12 has sides 26 and 28 that meet at spine edge 27 . In that regard, the spine edge 27 terminates with upper end feces 16 and 18 at one end and upper end faces 34 and 36 at the other, just as the embodiment shown in FIG. 6 . However, a pair of ducts 44 , 46 pass through the interior of the strut 12 . Specifically, the duct 46 passes from a first upper end face 32 at one end and terminates at the third upper end face 36 on the other. Note that the faces 32 , 36 that are connected by duct 46 are on opposite sides of the line of symmetry that passes through the spine edge 27 .
[0034] Still referring to FIG. 9 , a second duct 44 passes from a second upper face 30 at one end of the strut 12 to the fourth upper face 34 at the opposite end of the strut 12 . Analogously, the second upper face 30 and the fourth upper face 34 (which are connected by duct 44 ) are on the opposite sides of the line of symmetry that passes through spine edge 27 . These ducts will criss-cross one another (and may intersect) at an interior point within the strut 12 . These ducts 44 , 46 will allow the struts 12 , when assembled into a lattice structure (as in FIGS. 1-4 ) to create a manifold that allows cooling fluid to pass therethrough. Of course, the entire strut itself may be entirely hollow, which could also enable fluid to pass therethrough, even when assembled into a complex lattice structure as previously shown.
[0035] FIG. 10 isolates a bottom view of another embodiment, similar to the embodiment shown in FIG. 9 in that this embodiment bears a pair of criss-crossing internal ducts 48 , 49 . A first duct 48 extends between a first lower end face 18 on one end of the strut 12 to a third lower end face 22 on the other end. Conversely, there is a second duct 49 that passes from a second lower end face 16 at one end to a fourth lower end face 20 at the other. These ducts 48 , 49 will criss-cross one another (but not necessarily intersect) within an interior of the strut, and will allow the struts 12 , when assembled to create a manifold that allows cooling fluid to pass through a network of struts.
[0036] FIG. 11 represents a plan view of alternate embodiment of the strut 12 . In this embodiment, the interior portion of the strut is hollow; however, the remaining parts of the strut 12 are analogous. For example, the start of FIG. 11 includes a first side 26 that extends along a longitudinal axis L and terminates in an upper spine edge 27 .
[0037] FIG. 12 shows an end view of a hollow embodiment of the start 12 . In this view, the sides 26 , 28 and base 24 form a generally triangular configuration that encloses a hollow void V. The hollow configuration of FIG. 12 , of course, eliminates the end faces that are viewable in FIG. 6 . Conversely, the embodiment of FIG. 12 also eliminates the vertex point 14 that is shown in FIG. 6 as well.
[0038] FIG. 13 shows a bottom view of the hollow embodiment of the strut 12 . As shown the base 24 that forms an elongate hexagon that extends along longitudinal axis L and terminates with a triangular configuration adjacent the opening for void V. The void V allows cooling fluid to pass through the strut; when interconnected into a lattice structure (as in FIGS. 1-4 ), the void V allows cooling fluid to circulate through the entire lattice structure. Additionally, other devices or items, such as sensors, wiring, pumps, filters, motors, electronic devices, or the like may be positioned within the voids V. These devices may be positioned exterior the struts and within the lattice structure.
[0039] FIG. 14 shows a perspective view of three struts 12 . As shown, the lower end face 22 of one strut abuts and adjoins a lower end face 22 . These respective lower end faces 16 , 22 are formed so that they are generally identical and fit neatly onto one another. To wit, note that points a, b, and c of lower end face 18 of a first strut will meet and join with points a′, b′ and c′ of lower end face 16 of an adjacent strut. When these faces 16 , 22 adjoin as shown, an angled configuration formed to receive another strut 12 (not shown) will be formed by faces 18 of one strut and 20 of its adjoining strut (not viewable in FIG. 14 ; see FIG. 8 ) The ends of the struts are formed such that the end faces 16 , 18 , 20 , 22 will neatly fit into the angled configuration to form a tetrahedral configuration in three dimensions.
[0040] FIG. 15 shows a perspective view detailing how three struts 12 will fit together into a generally planar triangular configuration. The triangular configuration comprises three struts 12 adjoined at respective lower faces (see FIG. 11 ). In this configuration, the upper faces 30 , 32 , 34 , 36 of each strut are open to adjoin an adjacent triangular configuration so that a lattice structure of interconnected tetrahedrons will be formed (see FIGS. 1-4 ).
[0041] As shown in FIG. 15 , when the three struts are assembled in this manner, the upper faces 30 , 32 , 34 ,and 36 meet so that the vertex point 14 of each strut 12 abuts to form a single vertex. The spine edge 27 of each strut 12 faces outwardly from the triangular configuration, while the base 24 faces toward the interior of the triangular configuration.
[0042] Having described the invention in detail, it is to be understood that this description is for illustrative purposes only. The scope and breadth of the invention shall be limited only by the appended claims. | The disclosure depicts a high-strength yet lightweight material composed of interconnected struts that typically form a tetrahedral lattice structure. | 4 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of U.S. Provisional Application No. 61/994,635, filed May 16, 2014 and entitled “Portable Upright Stand” the entire disclosure of which is herein incorporated by reference for all purposes.
BACKGROUND
[0002] Embodiments of the present invention relate generally to portable upright stands for supporting string lighting or other displays. Creating temporary string lighting or other displays is difficult, especially in areas lacking suitable permanent structures for suspending lights and other decorations, and on varied terrain and surfaces, because of the challenge in transporting and erecting stable pole structures for support. It is also challenging to accommodate, add, and/or remove electrical power to such pole structures.
BRIEF SUMMARY
[0003] Various embodiments provide a portable upright stand that permits a user to support string lighting or other displays on any surface, indoors or outdoors, in the absence of, or in conjunction with, permanent structures. In some embodiments, the upright stand can include a base, a pole, one or more reservoirs, and a decorative shell. The base can be made of a light weight, durable and moldable material. The base can be coupled to the pole (or a sleeve of the pole where the pole can be collapsible into the sleeve). In some embodiments, the base can be designed for electrical wiring to come out of the bottom of the pole, extend through the base, and connect to an external power source. In some embodiments, the pole can serve to suspend a series of string lights and support insulated electrical wiring that can be connected to an external power source. Power can be provided to the series of string lights via the insulated electrical wiring. In certain embodiments, the one or more reservoirs can be filled with water to stabilize the portable upright stand. The decorative shell such as a wine barrel in some embodiments can be designed to surround the reservoir and provide an improved aesthetic.
[0004] Some embodiments provide a portable upright stand for supporting string lighting, the portable lighting stand including a base, a pole coupled to the base, and multiple reservoir containers. In some embodiments, the reservoir containers at least partially enclose a portion of the pole such that the pole is rotatably held by the reservoir containers. In some embodiments, each reservoir container has an opening for filling the reservoir container with ballast.
[0005] In some embodiments, the pole has a length of 7-12 feet. In some embodiments, the pole can be made of powder coated aluminum. In some embodiments, the pole is collapsible into a plurality of pole sections. In some embodiments, the reservoir containers include a shell configured to at least partially surround the reservoir containers. In some embodiments, the shell can be made of weather-resistant material. In some embodiments, each reservoir container includes hand grips. In some embodiments, each reservoir container has a second opening for draining ballast. In some embodiments, the pole can receive insulated electrical wiring extending through at least a portion of the pole. In some embodiments, the electrical wiring is coupled to another portable upright stand. In some embodiments, the base includes a sleeve for receiving the pole and a flange at the opposite end with holes. In some embodiments, the ballast comprises sand or water. In some embodiments, the portable upright stand is coupled to another portable upright stand through string lighting. In some embodiments, the reservoir containers are configurable to stacked in an interlocking manner.
[0006] Some embodiments provide a method of manufacturing a portable upright stand, including providing a base, providing a sleeve configurable to be coupled to the base, and providing one or more pole segments configurable to be coupled to the sleeve to form a pole. In some embodiments, the method further includes providing a plurality of reservoir containers capable of receiving water through an opening wherein the reservoir is configurable to at least partially enclose the sleeve. In some embodiments, the method further includes providing a shell configurable to at least partially surround the reservoir container. In some embodiments, the method further includes providing string lighting or other decorations to be coupled to the pole and supported by the portable upright stand. In some embodiments, the method further includes providing electrical wiring extendable from the top portion of the pole to another portable upright stand. In some embodiments, the method further includes coupling the electrical wiring to a power source.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 illustrates a cross-sectional view of an example upright stand according to some embodiments of the present invention.
[0008] FIG. 2 illustrates an exemplary process of assembling a portable upright stand according to some embodiments of the present invention.
[0009] FIG. 3A illustrates a perspective view of an example reservoir according to certain embodiments of the invention.
[0010] FIG. 3B illustrates a cross-sectional view of the example reservoir according to certain embodiments of the invention.
[0011] FIG. 4 illustrates a perspective view of another example reservoir according to certain embodiments of the invention.
[0012] FIG. 5 illustrates a cross-sectional view of an upright stand pole that is collapsible into multiple pole sections in accordance with some embodiments of the invention.
[0013] FIG. 6 illustrates a view of an example outdoor lighting system in accordance with some embodiments.
[0014] FIG. 7 illustrates a perspective view of an example reservoir 730 according to certain embodiments of the invention.
[0015] FIG. 8 illustrates a perspective view of another example upright stand 800 according to some embodiments of the present invention.
[0016] FIG. 9 illustrates a perspective view of an upright stand pole 920 with electrical wiring 950 according to some embodiments of the invention.
[0017] FIG. 10 illustrates a perspective view of another example upright stand 1000 according to some embodiments of the present invention.
[0018] FIG. 11A illustrates a perspective view of another upright stand pole 1120 and base 1110 assembly with electrical wiring 1150 according to some embodiments of the present invention.
[0019] FIG. 11B illustrates a side view of an upright stand pole 1120 and base 1110 assembly with electrical wiring 1150 according to some embodiments of the present invention.
[0020] FIG. 12 illustrates an exemplary process of assembling a portable upright stand according to some embodiments of the present invention.
DETAILED DESCRIPTION
[0021] Various embodiments provide a portable upright stand that permits a user to support string lighting or other displays on any surface, indoors or outdoors, in the absence of, or in conjunction with, permanent structures. In some embodiments, the upright stand can include a base, a pole, one or more reservoirs, and a decorative shell. The base can be made of a light weight, durable and moldable material. The base can be coupled to the pole (or a sleeve of the pole where the pole can be collapsible into the sleeve). In some embodiments, the base can be designed for electrical wiring to come out of the bottom of the pole, extend through the base, and connect to an external power source. In some embodiments, the pole can serve to suspend a series of string lights and support insulated electrical wiring that can be connected to an external power source. Power can be provided to the series of string lights via the insulated electrical wiring. In certain embodiments, the one or more reservoirs can be filled with water to stabilize the portable upright stand. The decorative shell such as a wine barrel in some embodiments can be designed to surround the reservoir and provide an improved aesthetic.
[0022] Some embodiments provide multiple reservoirs to be stacked against each other. Having multiple smaller-sized reservoirs as opposed to one large heavy reservoir allows a user to transport or move a filled reservoir or container more easily. The user may also stack as many reservoirs as needed for a particular occasion by having multiple reservoirs instead of a single large reservoir. If the user desires to have more weight to stabilize the portable upright stand or more height to the stand, the user may stack additional reservoirs on top of each other. While some embodiments enable the user to stack the reservoir tanks on top of one another, some embodiments enable the user to stack the reservoir tanks sideways to gain more surface area with the bottom surface (e.g., ground) or for a different aesthetic.
[0023] Various embodiments will now be described in greater detail with reference to the accompanying figures, beginning with FIG. 1 .
[0024] FIG. 1 illustrates a cross-sectional view of an upright stand 100 according to some embodiments of the present invention. In some embodiments, the portable upright stand 100 can include a base 110 , a pole 120 , a reservoir 130 , and a decorative shell 140 . The base 110 can be made of a light weight, durable and moldable material. In some embodiments, the base can be designed for electrical wiring 150 to come out of the bottom of the pole 120 and extend through the base 110 and connect to an external power source (not shown). The pole 120 can serve to suspend a series of string lights and to support insulated electrical wiring 150 for powering the series of string lights.
[0025] In some embodiments, the pole 120 can house electrical wiring 150 . In some embodiments, the electrical wiring 150 can be secured to the exterior of the pole 120 . The reservoir 130 can be filled with water (or other type of ballast such as rocks or sand) to stabilize the portable upright stand 100 and maintain the pole 120 in an upright orientation. The decorative shell 140 can be weather-resistant and designed to surround the reservoir 130 and can provide an improved aesthetic. In certain embodiments, the pole is stabilized with an anchor (e.g., tent stake, rebar stake, metal stake, helical pier, sand anchor, guide wires). In some embodiments, the portable upright stand can be used to display privacy screens, shade screens, umbrellas, flags, or other outdoor displays.
[0026] FIG. 2 illustrates an exemplary process 200 of assembling an upright stand according to some embodiments of the present invention. As described in FIG. 1 , an upright stand can include a base 110 , a pole 120 , a reservoir 130 , and a decorative shell 140 . Not every block described in process 200 must be performed to produce an upright stand in some embodiments while other embodiments may require additional steps. As described, the assembled portable upright stand can be coupled to a series of string lights in a string lighting system. The portable upright stand can be assembled using various techniques and a combination of materials in order to provide the desired durable, weather-resistant support for the series of string lights and to fit the aesthetic of the outdoor space to be illuminated.
[0027] At block 205 , process 200 can provide a base. As described, the base can be made of a light weight but durable material. In some embodiments, the shape can be one of a circular, rectangular, or other shape that can provide stability for a portable upright stand when one face of the base is placed against the ground. In certain embodiments, the base serves as a mold onto which one or more reservoirs may be placed and possibly locked.
[0028] At block 210 , process 200 can provide a sleeve configurable to be coupled to the base. At block 215 , process 200 can provide electrical wiring to be strung through the base and the sleeve. At block 220 , process 200 can provide one or more pole segments configurable to be coupled to the sleeve to form a pole. At block 225 , process 200 can provide a reservoir capable of receiving water through a first opening an releasing water through a second opening, where the reservoir includes a tunnel configurable to partially enclose the sleeve. In certain embodiments, the pole (e.g., 120 from FIG. 1 ) is preassembled in the reservoir (e.g., 130 from FIG. 1 ) to form a single unit. In some embodiments, the pole is removable and slides in and out of the reservoir. In some embodiments, the reservoir is removable from the portable upright stand assembly. A U-shaped reservoir can be used to slip around the pole in some embodiments.
[0029] In some embodiments, the pole is interlocked to the base (e.g., 1110 from FIG. 11A ) via a ring or a cap such as a ferrule (e.g., 924 from FIG. 9 ) or via a swaged end. In some embodiments, the pole can be mounted or interlocked onto the base via one or more locking buttons that are on the pole. In some embodiments, the pole is interlocked to the base without locking buttons. In some embodiments, the base has a sleeve with a permanently affixed flange at one end wherein the pole can be screwed into the other end of the sleeve or connected via interlocking ferrules, swaged ends, with or without locking buttons. In some embodiments, the base has a sleeve with a permanently affixed flange at one end and thumb screws at the other end wherein the pole can be coupled to the sleeve and stabilized or affixed by tightening the thumb screws.
[0030] In some embodiments, the base has a sleeve with a permanently affixed flange at one end wherein a plurality of reservoirs are placed on the base on top of the flange and at least partially surrounding the sleeve to support the pole. In some embodiments, the base can be coupled to the ground without a reservoir for support. In some embodiments, the base has holes and can be affixed to concrete, asphalt, or wood surfaces the ground (e.g., via a screw or other stabilizing components) without a reservoir for support using the holes. In some embodiments, the base has a sleeve with a permanently affixed flange with holes at one end wherein the base can be anchored to ground with stakes pounded through the flange holes into the ground. In certain embodiments, the pole is stabilized with an anchor (e.g., tent stake, rebar stake, metal stake, helical pier, sand anchor, guide wires) for additional reinforcement on varying surfaces. In some embodiments, a plurality of reservoirs with a circular shape from the top perspective and with a cylindrical tube (e.g., 133 from FIG. 1 ) may be stacked onto the base with sleeve from the top before the pole is coupled to the base.
[0031] At block 230 , process 200 can provide a decorative shell configurable to surround the reservoir. In some embodiments, the portable upright stand is designed so that approximately two inches of electrical wiring extends from the top of the pole 120 and approximately ten feet of grounded cord and plug extends from the bottom of the base.
[0032] FIG. 3A illustrates a perspective view of the reservoir according to certain embodiments of the invention. In some embodiments, the reservoir has a first opening (e.g., 131 from FIG. 1 ) on or near the top of the reservoir for filling the reservoir with water in order to add stability to the portable upright stand. The reservoir in certain embodiments can also have a second opening (e.g., 132 from FIG. 1 ) on or near the bottom of the reservoir for draining the water in order to increase the portability of the portable upright stand. In some embodiments, the first opening and/or the second opening can be sealed with a plug, screw-top, or other means to prevent unwanted flow into or out of the reservoir.
[0033] In some embodiments, the reservoir can have a closed annular body with a cylindrical tube through which the pole can be inserted and rotatably supported in an upright position substantially perpendicular to the base. In certain embodiments, the reservoir (also referred to as a tank or insert) can be made of a clear, durable, impermeable material. In some embodiments, the reservoir can hold ballast material other than water (e.g. sand, gravel, etc.). In certain embodiments, the reservoir has a capacity of approximately 15 gallons of water. In one embodiment, the reservoir has a size of 18 inches in width×18 inches in length×11 inches in height. In some embodiments, the reservoir has a circular shape from the top perspective with a cylindrical tube opening which the pole (not shown here) can be inserted. When inserted, the pole may thereby be supported in an upright position substantially perpendicular to the base.
[0034] FIG. 3B illustrates a second, cross-sectional view of the reservoir 130 according to certain embodiments of the invention showing the ballast material 134 inside the reservoir 130 . In some embodiments, the reservoir has top and bottom surfaces which are substantially parallel to the base and four sides with rounded edges and corners. In certain embodiments, the reservoir has a cylindrical body with top and bottom surfaces which are substantially parallel to the base.
[0035] FIG. 4 illustrates a perspective view of the reservoir according to certain embodiments of the invention. In some embodiments, the reservoir 130 has a U-shaped body with a center opening 135 in which the pole 120 (not shown here) can be inserted and rotatably supported in an upright position substantially perpendicular to the base 110 . In one embodiment, the reservoir 130 has a size of approximately 18 inches in width×18 inches in length×13 inches in height. In certain embodiments, the reservoir 130 has faces that are square or rectangular. In some embodiments, the reservoir 130 has rounded edges and/or corners. In some embodiments, the reservoir is collar shaped with round corners or square corners.
[0036] FIG. 5 illustrates a cross-sectional view of an upright stand pole 520 collapsed into multiple pole sections 521 in accordance with some embodiments of the invention. In some embodiments, the pole 520 may be a single non-collapsible pole. In some embodiments, the pole 520 can be collapsed into two or three sections. By having a pole that is collapsible into multiple sections enables convenient and efficient packaging and shipping. A pole of extended length to be assembled by a receiving user can be easily packaged when the pole may be broken down into a number of segments. Upon receiving the collapsed pole, the receiving user may then easily assemble the segments into a single pole. In some instances, the segments may be coupled tightly by connecting the edges of each segment to each other.
[0037] In some embodiments, the pole 520 is screwed into the base plate. In some embodiments, the pole 520 is two sections and attached to the base via a sleeve. In some embodiments, the pole 520 is finished to prevent corrosion. In some embodiments, the pole 520 is made of corrosion proof materials. In some embodiments, the pole 520 is ten feet in length. In other embodiments, the pole 520 is seven feet or twelve feet in length. In some embodiments, the pole 520 is three interlocking sections. In some embodiments, a pole section 521 is affixed to the base and configured to receive and support a single, longer pole section 521 of lesser diameter. In some embodiments, tapered ends are slidably mounted into wider ends for secure connection. In certain embodiments, the user of the portable upright stand can be a consumer who receives a manufactured lighting stand, pre-assembled, boxed and shipped with the pole sections 521 collapsed and with (or without) electrical wiring 550 running through the pole sections 521 . In some embodiments, the pole sections 521 are constructed from powder coated aluminum. In some embodiments the base 510 is a circular base plate. In some embodiments the base 510 is a circular base plate with welded tubing and screws for supporting poles 520 of varying size. In some embodiments, the pole 520 has a single section with electrical wiring 550 running through the pole. In some embodiments, the pole 520 has a single section with an extension cord running through the pole 520 . In some embodiments, the pole 520 does not support an electrical wiring 550 .
[0038] FIG. 6 illustrates a view of an example outdoor lighting system 601 including string lighting and exemplary portable upright stands 600 in accordance with some embodiments. Portable upright stand 600 can be part of a outdoor lighting system 601 in which a series of string lights is strung together, suspended, and connected to an electrical outlet. In one example, portable upright stand 100 can be incorporated into a system with a second portable upright stand 100 in an outdoor space where the first portable upright stand 100 suspends a series of string lights from its pole 120 and the second portable upright stand 100 both suspends a series of string lights from its pole 120 and also connects the series of string lights to a power source through its insulated electrical wiring 150 . In some embodiments, the decorative shell 140 has a size of approximately 21 inches×21 inches×30 inches. In certain embodiments, the decorative shell 140 is constructed of resin and includes openings for hands to grip and move the upright stand 100 . In some embodiments, the decorative shell 140 can have a stone-like design, wood design, or a basket weave pattern. In some embodiments, the reservoir 130 can have a decorative exterior. In some embodiments, a decorative shell 140 is not needed.
[0039] FIG. 7 illustrates a perspective view of an example reservoir 730 according to certain embodiments of the invention. In some embodiments, the reservoir 730 has a circular C-shape from the top perspective with a curved outer wall and a U-shaped center opening 735 which can be placed on top of a base (e.g., base 810 (not shown here) and slid around a pole (e.g., pole 920 (not shown here)) from the side thereby supporting the pole in an upright position substantially perpendicular to the base. In some embodiments, the reservoir 730 has ridges 736 at the top and bottom to provide an interlocking shape for coupling to other reservoirs such that a plurality of reservoirs 730 may be stacked and interlocked against each other.
[0040] In certain embodiments, the a circular C-shaped or U-shaped tank may be inserted onto the base pole with flange from the side. In some embodiments, a doughnut shaped tank may be inserted onto the base pole with flange.
[0041] FIG. 8 illustrates a perspective view of another example upright stand 800 according to some embodiments of the present invention. In some embodiments, the pole 820 has electrical wiring 850 entering through the side of the pole and extending through a portion of the pole 820 . In some embodiments, a plurality of reservoirs 830 may be stacked onto the base 810 . In some embodiments, the base 810 includes holes (for example hole 811 ). Each reservoir may be filled individually and stacked over each other in a sequential manner. Having multiple reservoirs can help stabilize the stand with more weight while making each unit more wieldy and easy to carry for an individual. This allows an individual who may not be able to or want to carry a very heavy reservoir to assemble the stand easily. The individual may simply stack each wieldable unit over each other. In some embodiment, the units may be interlocked against each other using ridges 836 in the top and bottom of each unit to provide further stability.
[0042] FIG. 9 illustrates a perspective view of an upright stand pole 920 with electrical wiring 950 according to some embodiments of the invention. In some embodiments, the pole 920 is hard wired internally with electrical wiring extending throughout the interior of the pole 920 . In some embodiments, the pole 920 includes a seal 923 at the top to prevent water from entering the pole 920 . The pole 920 can have exterior electrical receptacle 951 near or at the top of the pole 920 and a power in/male plug 952 on a wire tail 953 at or near the bottom of the pole 920 . The receptacle 951 may be exterior of the pole 920 or set flush against or on the pole 920 such that the pole 920 functions as a water tight electrical junction box. In some embodiments, the pole 920 includes an attachment 922 (e.g., clip, ring, eyelet, hook, or quick connect carabiner) for coupling to string lighting. In some embodiments, the attachment 922 is affixed to the top or sides of the pole 920 . In some embodiments, the attachment 922 supports an extension cord that is extending along the exterior of the pole 920 . In some embodiments, the junctions for the electrical wiring 950 are sealed in water tight containers with water tight and rigid connections.
[0043] FIG. 10 illustrates a perspective view of another example upright stand 1000 according to some embodiments of the present invention. In some embodiments, the pole 1020 includes a seal 1023 at the top to prevent water from entering the pole 1020 . The pole 1020 can have an attachment 1022 (e.g., clip, ring, eyelet, hook, or quick connect carabiner) for coupling to string lighting or other displays. In some embodiments, the attachment 1022 is affixed to the top or sides of the pole 1020 . In some embodiments, the attachment 1022 supports an extension cord that is extending along the exterior of the pole 1020 . In some embodiments, a plurality of reservoirs 1030 may be stacked onto the base 1010 . In some embodiments, each reservoir has a single opening 1031 for both filling and draining
[0044] FIG. 11A illustrates a perspective view of another upright stand pole 1120 and base 1110 assembly with electrical wiring 1150 according to some embodiments of the present invention. In some embodiments, the pole 1120 includes a seal 1123 at the top to prevent water from entering the pole 1120 and an attachment 1122 (e.g., clip, ring, eyelet, hook, or quick connect carabiner) for coupling to string lighting or other displays. In some embodiments, the attachment 1022 is affixed to the top or sides of the pole 1020 . The base 1110 may have a sleeve with a permanently affixed flange at one end. In some embodiments, the base 1110 has holes (for example 1111 ). In some embodiments, the pole 1120 includes a seal 1123 at the top to prevent water from entering the pole 1120 . The pole 1120 can have exterior electrical receptacle 1151 near or at the top of the pole.
[0045] FIG. 11B illustrates a side view of an upright stand pole 1120 and base 1110 assembly with electrical wiring 1150 according to some embodiments of the present invention. In certain embodiments, the upright stand may be assembled by an assembly process. The assembly process may include setting the base pole, setting one or more ballast containers on a base pole or slide in from the side, filling one or more containers (or the containers may be pre-filled before they are placed onto the base pole), stacking one or more remaining pole segments (if there are multiple segments in assembling the pole), and adding electrical to the pole in the event that there is no electrical wiring running inside the pole. Different embodiments may require different variations of the assembly process.
[0046] FIG. 12 illustrates an exemplary process 1200 of assembling an upright stand according to some embodiments of the present invention. As described in FIG. 8 , an upright stand can include a base 810 , a pole 820 , and a reservoir 830 . Not every block described in process 800 must be performed to produce an upright stand in some embodiments while other embodiments may require additional steps. As described, the assembled portable upright stand can be coupled to a series of string lights in a string lighting system. The portable upright stand can be assembled using various techniques and a combination of materials in order to provide the desired durable, weather-resistant support for the series of string lights and to fit the aesthetic of the outdoor space to be illuminated.
[0047] At block 1205 , process 1200 can provide a base comprising a sleeve with a permanently affixed flange at one end. At block 1210 , process 1200 can provide one or more C-shaped reservoirs capable of receiving and releasing water through an opening, wherein the reservoir includes a U-shaped void in the center configurable to partially enclose the sleeve. At block 1215 , process 1200 can fill each of the one or more reservoirs with ballast and stack on the base, on top of the flange and around the sleeve. At block 1220 , process 1200 can provide one or more pole segments configurable to be coupled to the sleeve to form a pole. At block 1225 , process 1200 can provide insulated electrical wiring to be coupled to the pole. At block 1230 , process 1200 provides a decorative shell configurable to surround the reservoir.
[0048] In the foregoing specification, aspects of the invention are described with reference to specific embodiments thereof, but those skilled in the art will recognize that the invention is not limited thereto. Various features and aspect of the above-described invention may be used individually or jointly. Further, embodiments can be utilized in any number of environments and applications beyond those described herein without departing from the broader spirit and scope of the specification. The specification and drawings are, accordingly, to be regarded as illustrative rather than restrictive.
[0049] Other variations are within the spirit of the present disclosure. Thus, while the disclosed techniques are susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the disclosure to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions and equivalents falling within the spirit and scope of the disclosure, as defined in the appended claims.
[0050] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the disclosed embodiments (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. The phrase “based on” should be understood to be open-ended, and not limiting in any way, and is intended to be interpreted or otherwise read as “based at least in part on,” where appropriate. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments of the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.
[0051] Disjunctive language such as the phrase “at least one of X, Y, or Z,” unless specifically stated otherwise, is otherwise understood within the context as used in general to present that an item, term, etc., may be either X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that certain embodiments require at least one of X, at least one of Y, or at least one of Z to each be present.
[0052] Additionally, conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, should also be understood to mean X, Y, Z, or any combination thereof, including “X, Y, and/or Z.”
[0053] Preferred embodiments of this disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor expects skilled artisans to employ such variations as appropriate, and the inventor intends for the disclosure to be practiced otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context. | Embodiments include systems, methods, and apparatuses for providing a portable upright stand. A portable upright stand can include a pole for suspending objects such as string lighting, protective coverings, etc. The pole can be coupled to a base such that electrical wiring may extend through the pole and the base. The portable upright stand can also include a reservoir that can enclose at least a portion of the pole such that the pole can be stabilized by the reservoir. The reservoir can have a first opening for filling the reservoir with water and a second opening for draining water. The portable upright stand can also have a shell that can be configured to surround the reservoir as decor or as a protective covering. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to evacuation of odoriferous near commodes by drawing air from the environment of the commode and discharging the same.
BACKGROUND OF THE INVENTION
[0002] Use of commodes typically entails release of objectionable odors into the atmosphere. Current practice is to provide bathrooms with exhaust fans for discharging odoriferous air. However, exhaust fans are typically located high in the room, at the ceiling in most cases. This causes fouled air to blend with the remaining air, so that the atmosphere of nearly the entire room becomes fouled. While an exhaust fan may eventually evacuate the fouled air, there is still considerable opportunity for the odor firstly, to permeate the entire room, and secondly, to spread beyond the bathroom.
[0003] The prior art has suggested diverse devices to collect air from the immediate vicinity of a commode, and to discharge this air. While this approach seems intuitively superior to depending on a wall or ceiling mounted exhaust fan, most executions of the approach cause the apparatus to become unduly cumbersome and impractical. For example, most air collection devices are self-contained, having a fan integral thereto. Not only does this cause the air collection device to become heavier and more expensive, but it further introduces the necessity of incorporating a power supply such as a battery, or introduces necessity of connecting to a wall mounted electrical receptacle.
[0004] There remains a need for an air evacuation system which draws from the immediate vicinity of the commode, and yet which is uncomplicated and practical.
SUMMARY OF THE INVENTION
[0005] The present invention provides apparatus which collects and disposes of air from the vicinity of a commode. The apparatus draws from the immediate vicinity of the commode and conducts collected air to a room exhaust fan. The apparatus comprises an inlet mountable to the commode, a conduit extending to the inlet grille of the exhaust fan, and an enclosure which constrains the exhaust fan to draw exclusively or almost exclusively from the conduit, thereby maximizing effectiveness of the air evacuation system.
[0006] The conduit is adapted to mount to room surfaces, such as the partition and ceiling, thereby being minimally intrusive with respect to the room, and for secure anchorage on the commode. The entire apparatus is uncomplicated, lightweight, inexpensive, and easily installable. Reliance upon integral power providing and utilizing apparatus is eliminated.
[0007] The invention may comprise a kit providing at least most of the components necessary to complete installation within a room, such as clips for wall and ceiling mounting of the conduit, and an anchor for mounting one end of the system to the commode.
[0008] It is an object of the invention to provide an air evacuation system for controlling and discharging odors from commodes.
[0009] Another object of the invention is that the air evacuation system be uncomplicated, inexpensive, and easily installed.
[0010] It is an object of the invention to provide improved elements and arrangements thereof by apparatus for the purposes described which is inexpensive, dependable, and fully effective in accomplishing its intended purposes.
[0011] These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
[0013] FIG. 1 is a perspective environmental view of a room improved by incorporating apparatus of the invention, according to at least one aspect of the invention.
[0014] FIG. 2 is an exploded perspective detail view of a component of the apparatus, seen near the top of FIG. 1 .
[0015] FIG. 3 is an enlarged front view of the connection of the novel system at the commode, and is shown partially in cross section.
[0016] FIG. 4 is an enlarged perspective detail view of a component facilitating the installation as seen in FIG. 1 .
[0017] FIG. 5 is an enlarged perspective detail view of a washer that may be utilized with the component of FIG. 4 .
[0018] FIG. 6 is a front view of a variation of the installation of FIG. 1 , wherein there is no actual contact between the novel system and the associated commode.
[0019] FIG. 7 is an enlarged perspective detail view of an alternative form to a terminus of the apparatus of the novel system.
[0020] FIG. 8 is an enlarged perspective detail view of a connector which may be part of the apparatus of the novel system.
[0021] FIG. 9 is a top perspective view of a component of the apparatus of the novel system.
[0022] FIG. 10 is a front perspective cross sectional view of the component of FIG. 9 , taken along line 10 - 10 of FIG. 9 .
[0023] FIG. 11 is similar to FIG. 10 , but is taken along line 11 - 11 of FIG. 9 .
[0024] FIG. 12 is similar to FIG. 10 , but is taken along line 12 - 12 of FIG. 9 .
[0025] FIG. 13 is an enlarged perspective view of a fastener which may be used with some of the components of FIG. 1 .
DETAILED DESCRIPTION
[0026] Referring first to FIG. 1 , according to at least one aspect of the invention, there is shown apparatus 100 for collecting and discharging odoriferous air from the vicinity of a commode 10 located in a room 12 provided with an exhaust fan 14 (not visible in its entirety) having an inlet to receive air from the room 12 . The apparatus 100 may comprise an intake member 102 having an intake end 154 and a discharge end 106 of configuration different from that of the intake end 154 . Air inducted from the intake member 102 flows into a conduit 108 which is insertably compatible with the discharge end 106 of the intake member 102 . Air flows through the conduit 108 to an adapter housing 110 which is disposed to connect the elongated conduit 108 to the inlet of the exhaust fan 14 . The adapter housing 110 also substantially seals against draw of air by the exhaust fan 14 from the atmosphere outside the adapter housing 110 . It will be understood that air flow through the apparatus 100 is effected by the exhaust fan 14 .
[0027] The adapter housing 110 may be large enough to cover the inlet of the exhaust fan 14 , and may comprise an inlet opening 112 formed therein. The inlet opening 112 may be dimensioned and configured to be connectably compatible with the conduit 108 , or alternatively, to comprise an adapter (not shown) effecting connection and retention of the conduit 108 to the adapter housing 110 . The adapter housing is open at its upper end as depicted in FIG. 1 , thereby forming an outlet opening 114 of cross sectional area at least about as great as that of the inlet of the exhaust fan 14 .
[0028] FIG. 2 shows further details of the adapter housing 110 . The adapter housing 110 may comprise a louvered zone bearing openable and closable louvers 116 and a manual control 118 for opening and closing the louvers 116 . The manual control 118 may comprise a lever (not separately shown) which moves the louvers 116 , which are pivotally mounted to the adapter housing 110 . The end of the lever may be is exposed for access for manual operation. The louvers 116 may be opened to enable the exhaust fan 14 to be used to evacuate air from the vicinity of the adapter housing 110 without drawing air through the conduit 108 , when it is desired to utilize the exhaust fan 14 in conventional fashion. To utilize the apparatus 100 rather than to utilize the exhaust fan 14 conventionally, the louvers 116 are closed.
[0029] The adapter housing 110 may be formed in a first component 120 and a second component 122 bearing the louvers 116 , which second component 122 is removable from the first component 120 . The first component 120 may comprise four walls which define the final volume of the adapter housing 110 , as well as the inlet opening 112 . Forming the adapter housing in two components 120 , 122 may be done for manufacturing convenience, to expose fasteners for mounting the first component 120 to the ceiling or to the exhaust fan 14 , to enable access to the fan 14 for servicing, or for other reasons.
[0030] Turning now to FIG. 3 , the intake member 102 may be dimensioned and configured to fit between the toilet seat 16 and the upper surface of the bowl 18 of the commode 10 . When installed between the toilet seat 16 and the upper surface of the bowl 18 , the intake member 102 may fit without displacing the toilet seat 16 from its normal position when in use.
[0031] Referring to FIGS. 4 and 5 , in order to keep the intake member 102 in place, the apparatus 100 may include an anchor 124 which is retainably engageable with the mounting structure of the toilet seat 16 . Notably, the anchor 124 may comprise a first section 126 bearing a central opening 128 for passing a threaded fastening shaft of the mounting structure (not separately shown) of the toilet seat 16 therethrough. Such mounting structure typically includes a bolt or threaded stud which passes through a hole formed in the bowl of the commode. The toilet seat 16 may be temporarily removed to enable the central opening 128 of the anchor 124 to be placed over the bolt or stud, after which the toilet seat 16 may be replaced. To assure that the toilet seat 16 be symmetically displaced from the upper surface of the bowl 18 at both left and right sides after installation of the anchor 124 , the apparatus 100 may comprise a washer 130 (see FIG. 5 ) of thickness 132 equal to the thickness 134 of the first section 126 of the anchor 124 .
[0032] The anchor 124 may have a holding element for engaging and holding the intake member 102 so that the intake member 102 may be secured to the commode 10 by engagement with the mounting structure of the toilet seat 16 . This holding element may comprise a second section bearing a fastening element for engaging and securing the intake member 102 . This holding element may take the form of a tab or enlarged head 136 . The fastening element may comprise adhesive 138 . A neck 140 may project from the first section 126 to the second section, for connecting the former to the latter.
[0033] As seen in FIG. 6 , it would be possible to mount the intake member 102 near the toilet seat 16 but not in as close proximity as seen in FIG. 3 .
[0034] In a further option seen in FIG. 7 , an intake member 102 A, which in other ways may be a structural and functional equivalent of the intake member 102 , may comprise flaccid constituent material, which lends itself to being manually formed to conform to diverse environmental elements (not shown) which might if present prevent installation as seen in FIG. 3 . The intake member 102 A may comprise a constrictive elastic band 142 for engaging the conduit 108 . By contrast with flaccid construction of the intake member 102 A, the intake member 102 may be sufficiently rigid as hold its form in the absence of forces which would distort its form.
[0035] As seen in FIG. 1 , the conduit 108 comprises at least one section 144 which has at least one flat, planar side so as to be flushly mountable to a flat, planar wall or partition 20 of the room 12 . In the installation as depicted in FIG. 1 , the conduit 108 comprises not only the central section 144 , but also a section 146 extending along the ceiling 22 , and a short section 148 extending from the partition 20 to the intake member 102 .
[0036] To facilitate installation in rooms of different layouts and dimensions, the apparatus 100 may be provided with components enabling ready assembly. For example, the installation seen in FIG. 1 includes two connector sleeves in the form of elbow fittings 150 each of which is disposed to receive therein and to mutually connect two adjacent sections of the conduit 108 disposed at a right angle to one another. This arrangement enables the conduit 108 to be mounted flushly to the ceiling 22 of the room and to a wall or partition such as the partition 20 , while making transition between vertical orientation (i.e., extending along the partition 20 ) and horizontal orientation (i.e., extending along the ceiling 22 ).
[0037] The elbow fittings 150 may be dimensioned and configured to slip over the exposed ends of the various sections of the conduit 108 , such as the sections 144 , 146 , and 148 , and to engage these by friction. It will also be appreciated that the conduit 108 may be formed from lengths of stock material such as a synthetic resin, and may be easily cut to suit in order to be installed in rooms of different characteristics. Therefore, it would be possible to provide connector sleeves such as a straight connector sleeve 152 , shown in FIG. 8 , for joining conduit sections in straight alignment. Connection of the various conduit sections to one another enables a conduit such as the conduit 108 to be built up in overall length by connecting the plural sections serially so as to be able to span the distance from the intake member 102 to the adapter housing 110 regardless of the specific dimensions and configuration of the room.
[0038] FIG. 9 illustrates how the intake member 102 accommodates both the narrow gap between the toilet seat 16 and the bowl 18 of the commode, and also the configuration of the end of the conduit section 148 . As seen in FIG. 3 , the distal end 154 of the intake member 102 must be of low profile to fit between the toilet seat 16 and the bowl 18 . Yet at its proximal end 156 , the intake member 102 must be greater in height to match the configuration of the conduit section 148 . This transition is preferably but not necessarily made gradually and progressively, as seen in FIGS. 9 , 10 , 11 , and 12 , where it is seen from three arbitrarily selected cross sections that the height of the intake member 102 progressively increases from the distal end 154 to the proximal end 156 .
[0039] Referring to FIG. 13 , the apparatus 100 may be provided with one or more a three sided clip 158 for mounting the conduit 108 to the partition 20 or ceiling 22 of the room 12 . The clip 158 may comprise a base section 160 , a first side grip section 162 extending from the base section 160 at a substantially right angle thereto, and a second side grip section 164 spaced apart from the first side grip section 162 and extending from the base section 160 at a substantially right angle thereto. The clip 158 may be provided with a hole 166 for receiving the shaft of a fastener such as a screw 168 if desired, although it would be possible to delete the hole 166 since holes are easily drilled.
[0040] The invention may also be thought of as a method of collecting and discharging odoriferous air from the vicinity of a commode such as the commode 10 located in a room such as the room 12 , which is provided with an exhaust fan such as the exhaust fan 14 . The method may comprise the steps of providing an air intake member such as the air intake member 102 at the immediate vicinity of the commode; providing a conduit such as the conduit 108 disposed to conduct air from the air inlet to the immediate vicinity of the exhaust fan; providing an adapter housing such as the adapter housing 110 , which covers the inlet of the exhaust fan and which receives the distal end of the conduit, and which substantially seals the inlet of the exhaust fan to infiltration of ambient air of the room; operating the exhaust fan; transporting collected air to the exhaust fan; and discharging collected air using the exhaust fan as the only air propulsion device acting to evacuate air from the vicinity of the commode and to the exterior of the room.
[0041] The method may be amplified to comprise the further step of causing the conduit to extend from the commode to a vertical surface of the room, such as the partition 20 . The method may further comprise a step of causing the conduit to extend along the ceiling of the room, such as the ceiling 22 , to the adapter housing. The method may comprise a further step of anchoring the intake member to the commode, and a still further step of installing the intake member between the rim of the commode and the seat of the commode.
[0042] While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is to be understood that the present invention is not to be limited to the disclosed arrangements, but is intended to cover various arrangements which are included within the spirit and scope of the broadest possible interpretation of the appended claims so as to encompass all modifications and equivalent arrangements which are possible. | Apparatus for collecting and disposing of air from the vicinity of a commode, utilizing a room exhaust fan. The apparatus may comprise an air intake member mountable to the commode, a conduit extending to the inlet grille of the exhaust fan, and an adapter housing which fits over the intake of the fan and constrains the exhaust fan to draw exclusively or almost exclusively from the conduit. The conduit may comprise flat sided plural sections, with connecting sleeves and right angled elbow connectors. The adapter housing may bear closable louvers. The air intake member may be mounted to the commode using an adhesive bearing anchor, occupying the space between the bowl and the toilet seat. The apparatus may include clips for securing the conduit to a wall surface. The air intake member may be rigid or flaccid. | 4 |
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